Note: Claims are shown in the official language in which they were submitted.
68
THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A process for plating a coating of a noble metal
onto a non-noble metal substrate material, said process
comprising the steps of:
a) preparing a starter aqueous plating solution
containing an amount of free ions of a noble metal to be
plated out onto said substrate material, said noble metal
being selected from the group consisting of silver, gold,
platinum, palladium, iridium, rhodium, ruthenium and osmium,
such that said amount of free ions of said noble metal is
sufficient to plate an amount of an active, non-noble metal
substrate material, in the form of a powder, with a coating
of from 2 to 60 weight percent, based on the total weight of
a final noble metal-coated active non-noble metal substrate
material product, and such that said amount of free ions of
said noble metal plated onto said active non-noble metal
substrate material is sufficient to at least provide a
coating on the surface of said active non-noble metal
substrate material that completely covers the entire surface
of said active non-noble metal substrate material, leaving no
exposed surface of said active non-noble metal substrate
material, said non-noble metal substrate material being
selected from the group consisting of copper, nickel,
aluminum, titanium, zirconium, vanadium, hafnium, cadmium,
niobium, tantalum, molybdenum, tungsten, gallium, indium,
thallium, and combinations of a first one of said non-noble
metal substrate materials seeded with atoms of a second one
of said non-noble metal substrate materials having a greater
affinity than that of said first non-noble metal substrate
material for said selected noble metal to be plated thereon;
b) dividing said starter plating solution, prepared in
step (a), into a plurality of portions, such that each
portion of said starter plating solution contains a
percentage amount of from less than about 1% to about 85%, by
weight, of the total amount of free ions of noble metal to be
plated out that are contained in said starter plating
solution, the percentage amount that is present in any said
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portion being the same as or different from the percentage
amount present in other of said portions;
c) preparing a plurality of individual plating
solution baths into which said active non-noble metal
substrate material is immersible, by selecting a
concentration of free ions of noble metal for each said
plating solution bath which is to be made from a
corresponding one of said plurality of portions of said
starter plating solution, prepared in step (b), said
concentration of free ions of noble metal for each said
individual plating solution bath being in the range of from
about 0.3 to about 65 grams of free ions of noble metal per
liter of plating solution bath, and making each said
individual plating solution bath by adding water to each
corresponding one of said plurality of portions of said
starter plating solution, to increase the volume thereof ,
such that each one of said plurality of individual plating
solution baths has the concentration of free ions of noble
metal, as selected above therefor;
d) immersing an amount of an active non-noble metal
substrate material to be plated into one of said individual
plating solution baths, prepared in step (c), which is
maintained at a temperature in the range of from about 20 °C
to about 100 °C, such that the temperature of said individual
plating solution bath is inversely related to the oxidation
potential of the non-noble metal substrate material being
plated, to cause said free ions of noble metal to plate-out
onto said substrate material until said one of said
individual plating solution baths is depleted of all but a
trace amount of said free noble metal ions contained therein,
thereby forming an intermediate plated substrate material on
which is plated the fraction of free ions of noble metal
contained in said one of said individual plating solution
baths;
e) separating said intermediate plated substrate
material, prepared in step (d), from the depleted plating
solution bath;
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f) rinsing said intermediate plated substrate
material, separated in step (e), at least once with a first
series of water rinses;
g) repeating steps (d), (e), and (f) with the rinsed
intermediate plated substrate material resulting from each
previous sequence of steps (d), (e), and (f), and another one
of said individual plating solution baths, until all of said
individual plating solution baths prepared according to step
(c) have been utilized, the sequence of utilization of said
individual plating solution baths being such that when the
concentration of free noble-metal ions in at least two of
said individual plating solution baths is different, said
individual plating solution baths are successively utilized
in the order of decreasing concentration of free ions of
noble metal therein, and further such that the temperature of
each successively utilized individual plating solution bath
is at least as high as the temperature of the preceding
individual plating solution bath, thereby forming further
intermediate plated substrate materials with each repetition
of the sequence of steps (d), (e) and (f), such that each
successive intermediate plated substrate material is
cumulatively plated with the amounts of free ions of noble
metal contained in each of the plating solution baths into
which the intermediate plated substrate material has been
immersed, thereby ultimately forming a final plated substrate
material, onto which has been plated the total said amount of
free ions of noble metal in said original starter plating
solution;
h) rinsing said final plated substrate material,
prepared in step (g), at least once with a second series of
rinses, including rinses with water, an acid, and an alcohol;
i) further rinsing said final plated substrate
material, as rinsed according to step (h), at least once with
a third series of rinses, including rinses with water, and an
alcohol; and
j) drying said final plated substrate material, as
rinsed according to step (i), to produce a final noble
metal-coated active non-noble metal substrate material product.
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2. The process of claim 1 wherein said noble metal is
selected from the group consisting of silver, gold, and
platinum, and said non-noble metal substrate material is
selected from the group consisting of copper, nickel,
copper-seeded aluminum, titanium, and zirconium.
3. The process of claim 1 wherein the starter aqueous
plating solution is prepared by dissolving an amount of a
compound selected from the group consisting of a cyanide,
chloride, nitrate, and an oxide of the noble metal, in
boiling water, to which has first been added an amount of an
alkali metal cyanide of from about 0to 2.5 times the weight
of the selected noble metal compound, the amount utilized
being determined by the degree of solubility of the noble
metal-containing compound in water, such that the amount of
alkali metal cyanide utilized is sufficient to effect
dissolution of the selected noble metal compound in the
solution to produce the desired amount of free ions of the
noble metal.
4. The process of claim 3 wherein when the noble metal
is gold, supplied in any of the selectable forms of noble
metal compound, the amount of alkali metal cyanide utilized
is zero, and further wherein is added to the boiling water
prior to addition of the gold-containing compound, a mixture
of ammonium chloride, sodium citrate and sodium hypophosphate
in a weight ratio of from about 7.0 - 8.0 : 4.5 - 5.5 : 1,
with the overall amount of mixture added to the water being
such that the weight of sodium hypophosphate in the mixture
is from about 2.0 to 2.5 times the weight of the
gold-containing compound.
5. The process of claim 3 wherein the noble metal
oxide is selected from the group consisting of silver oxide,
gold oxide and platinum mon-, di- and tri-oxide.
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6. The process of claim 3 wherein the noble metal
cyanide is selected from the group consisting of silver
cyanide, gold cyanide, platinum cyanide, potassium
cyanoaurate, potassium cyanoargentate, potassium
cyanoplatinite, sodium cyanoaurite and sodium cyanoplatinite.
7. The process of claim 3 wherein the noble metal
chloride is selected from the group consisting of silver
chloride, gold chloride, platinum chloride, potassium
chloroaurate, potassium tetra- and hexa-chloroplatinate,
sodium chloroaurate, sodium chloro- and hexachloro-platinate
and sodium chloroplatinite.
8. The process of claim 3 wherein the noble metal
nitrate is selected from the group consisting of silver
nitrate, gold nitrate, potassium nitroplatinite and sodium
nitroplatinite.
9. The process of claim 6 wherein the alkali metal
cyanide is selected from the group consisting of sodium
cyanide and potassium cyanide.
10. The process of claim 1 wherein said powder of
active, non-noble metal substrate material has spherical,
flake-shaped or irregular-shaped particles.
11. The process of claim 10 wherein said powder of
active, non-noble metal substrate material has spherical
particles.
12. The process of claim 10 wherein said spherical
particles have a mean diameter of from 5 to 15 microns.
13. The process of claim 10 wherein the largest
dimension of the flake-shaped and irregular-shaped particles
is 20 microns.
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14. The process of claim 1 wherein the coating of noble
metal plated onto the non-noble metal substrate material is
from 15 to 25 weight percent, based on the total weight of
final noble metal-coated active non-noble metal substrate
material product.
15. The process of claim 1 wherein the starter plating
solution is divided into from 2 to 5 portions.
16. The process of claim 1 wherein a first portion of
the plurality of portions into which said starter plating
solution is divided contains from about 20% to about 85%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; a
second portion of the plurality of portions into which said
starter plating solution is divided contains from about 15%
to about 55%, by weight, of the total amount of free ions of
noble metal to be plated out, contained in said starter
plating solution; where a third portion is utilized, said
third portion contains from about 1% to about 30%, by weight,
of the total amount of free ions of noble metal to be plated
out, contained in said starter plating solution; where a
fourth portion is utilized, said fourth portion contains
from about 0.1% to about 30%, by weight, of the total
amount of free ions of noble metal to be plated out,
contained in said starter plating solution; and where a
fifth or subsequent portion is utilized, each of said fifth
and subsequent portions contains less than about 1%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; such
that the sum of the percentages in all of the portions is
100%.
17. The process of claim 1 wherein the separation of
plated substrate material from a depleted plating solution
bath is by decantation.
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18. The process of claim 1 wherein the first series of
rinses of plated substrate material comprises a sequence of
steps selected from the group consisting of rinsing twice in
succession with cold water; rinsing once with warm water,
followed by rinsing once with hot water; and rinsing twice
in succession with hot water.
19. The process of claim 1 wherein the second series of
rinses of final plated substrate material comprises the
sequence of steps of rinsing once with hot water; rinsing
once with a weak acid; rinsing a second time with hot water;
and rinsing once with an alcohol.
20. The process of claim 19 wherein the weak acid is an
aqueous solution of an acid selected from the group
consisting of glacial acetic acid, dilute hydrochloric acid,
dilute nitric acid, and hydrazine.
21. The process of claim 20 wherein the weak acid is an
aqueous solution of 25% glacial acetic acid.
22. The process of claim 19 wherein the alcohol is a
lower alkanol having from 1 to 4 carbon atoms.
23. The process of claim 22 wherein the lower alkanol is
methanol.
24. The process of claim 1 wherein the second series
of rinse steps is performed in sequence from one to four
times.
25. The process of claim 24 wherein the second series
of rinse steps is performed four times.
26. The process of claim 1 wherein the third series of
rinses of final plated substrate material comprises the
sequence of steps of rinsing from 1 to 3 times in succession
with hot water, followed by rinsing in succession from 1 to
3 times with an alcohol.
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27. The process of claim 26 wherein the alcohol is a
lower alkanol having from 1 to 4 carbon atoms.
28. The process of claim 27 wherein the lower alkanol
is methanol.
29. The process of claim 26 wherein 3 hot water rinses
in succession, followed by 3 alcohol rinses in succession are
performed.
30. The process of claim 29 wherein the alcohol is
methanol.
31. The process of claim 1 wherein drying of the final
plated substrate material is by at least one of the methods
selected from the group consisting of washing with acetone;
washing with methanol; air drying at ambient temperature and
pressure; air drying with hot air; and vacuum drying under
reduced pressure.
32. The process of claim 1 wherein a non-noble metal
substrate which is contaminated with one or more of an outer
oxidized layer; a coating of dirt; and a coating of grease,
all of which reduce the activity and susceptibility of the
non-noble metal to be plated with noble metal ions,
is first cleaned and made active before commencement of
plating by washing with a cleaning and activating solution.
33. The process of claim 32 wherein the cleaning and
activating solution is selected from the group consisting of
a sodium or potassium hydroxide solution and a sodium or
potassium cyanide solution.
34. The process of claim 33 wherein if the cleaning
and activating solution is potassium cyanide solution, the
substrate is first mixed with a liquid detergent before
washing with the solution.
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35. The process of claim 1 further comprising mixing
the active non-noble metal substrate material with a liquid
detergent prior to immersing the substrate material in the
first plating solution bath.
36. The process of claim 1 further comprising the step
of repeating said first series of water rinse steps,
according to step (f), once, after completion of the first
series of rinse steps, which follows immersion of the plated
substrate material in the individual plating solution bath
in which the substrate material is plated with the percentage
of free ions of noble metal cumulatively amounting to at
least 85% of the total amount of free ions of noble metal to
be plated out, with there then remaining at least one more
plating solution bath in which plating of the remaining
percentage of free ions of noble metal onto the substrate
material is completed.
37. The process of claim 33 wherein the cleaning and
activating solution is a sodium or potassium hydroxide
solution which has a concentration of from 0.5 to 1.5
grams/liter.
38. The process of claim 33 wherein the cleaning and
activating solution is a sodium or potassium cyanide solution
which has a concentration of from 50 to 60 grams/liter.
39. The process of claim 1 wherein the non-noble metal
substrate material to be plated is first seeded with atoms of
another non-noble metal onto which the noble metal ions more
readily plate.
40. The process of claim 39 wherein the seeding is
performed by washing the substrate material with a solution
containing free ions of the seeding metal.
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41. The process of claim 40 wherein the free ions of
the seeding metal are supplied by dissolving a salt of the
seeding metal in water and adding ammonium hydroxide and
potassium cyanide thereto to maintain the ions of the seeding
metal free in solution.
42. A process for plating silver onto copper according
to claim 1 wherein said noble metal is silver; said non-noble
metal substrate material is copper powder having spherical
particles with a mean diameter of from 5 to 15 microns; the
weight of coating is from 15 to 60 weight percent, based on
the total weight of a final noble metal-coated non noble
metal substrate material product; said starter plating
solution is divided into 5 portions with 5 said individual
plating solution baths being prepared therefrom, such that
75% to 85% of the total amount of free ions of noble metal to
be plated out is contained in the first individual plating
solution bath; 10% to 20% of the total amount of free ions of
noble metal to be plated out is contained in the second
individual plating solution bath; 1% to 5% of the total
amount of free ions of noble metal to be plated out is
contained in the third individual plating solution bath; and
0.1% to 0.5% of the total amount of free ions of noble metal
to be plated out is contained in each of the fourth and fifth
individual plating solution baths, such that the total of all
percentages of amounts of free ions of noble metal to be
plated out in the 5 baths is 100%; the first individual
plating solution bath is maintained at a temperature of from
about 50 °C to about 80 °C; the second through fifth
individual plating solution baths are maintained at a
temperature of from about 85 °C to about 100 °C; said first
series of water rinse steps is performed once and comprises
the sequence of steps of rinsing once with warm water,
followed by rinsing once with hot water; said second series
of rinse steps is repeated 4 times in succession after
completion of the first series of water rinse steps following
plating in the fifth individual plating solution bath, and
comprises the sequence of steps of rinsing once with hot
water; rinsing once with a 25% glacial acetic acid aqueous
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solution; rinsing a second time with hot water; and rinsing
once with methanol; said third series of rinse steps is
performed once and comprises the sequence of steps of rinsing
3 times with hot water, followed by rinsing 3 times with
methanol; and said process further comprises performing a
second series of rinse steps once, after completion of the
first series of rinse steps which follows after plating in
the third individual plating solution bath.
43. The process according to claim 42 wherein drying of
the final plated substrate material is by air drying at
ambient temperature and pressure.
44. The process according to claim 42 wherein the
weight of coating is from 15.0 to 25.0 weight percent, based
on the total weight of final noble metal coated active
non-noble metal substrate material product.
45. The process according to claim 42 wherein the
weight of coating is 17.6 weight percent, based on the total
weight of final noble metal coated active non-noble metal
substrate material product, and 80% of the total amount of
free ions of noble metal to be plated out is contained in the
first individual plating solution bath; 16% of the total
amount of free ions of noble metal to be placed out is
contained in the second individual plating solution bath;
3.2% of the total amount of free ions of noble metal to be
plated out is contained in the third individual plating
solution bath; and 0.4% of the total amount of free ions of
noble metal to be plated out is contained in each of the
fourth and fifth individual plating solution baths.
46. A process for plating silver onto nickel according
to claim 1 wherein said noble metal is silver; said non-noble
metal substrate material is nickel powder having spherical
particles with a mean diameter of from 5 to 15 microns; the
weight of coating is from 15 to 60 weight percent, based on
the total weight of final noble metal coated active non-noble
metal substrate material product; said starter plating
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solution is divided into 4 equal portions with 4 said
individual plating solution baths being prepared therefrom,
such that 25% of the total amount of free ions of noble metal
to be plated out is contained in each individual plating
solution bath; the first individual plating solution bath is
maintained at a temperature of from about 50 °C to about 80
°C; the second through fourth individual plating solution
baths are maintained at a temperature of from about 85 °C to
about 100 °C; said first series of water rinse steps
comprises the sequence of steps of rinsing twice with hot
water; said second series of rinse steps is repeated 4 times
in succession after completion of said first series of water
rinse steps following plating in the fourth individual
plating solution bath, and comprises the sequence of steps of
rinsing once with hot water; rinsing once with a 25% glacial
acetic acid aqueous solution; rinsing a second time with hot
water; and rinsing once with methanol; said third series of
rinse steps is performed once and comprises the sequence of
steps of rinsing 3 times with hot water, followed by rinsing
3 times with methanol; and said process further comprises
cleaning and activating said nickel powder substrate material
prior to its immersion in the first individual plating
solution bath.
47. The process of claim 46 wherein cleaning and
activation of the nickel powder comprises the steps of first
mixing the nickel powder with liquid detergent to form a
paste; mixing the nickel powder paste with a potassium
cyanide activation solution; separating the cleaned and
activated nickel powder from the activation solution; washing
the activated nickel powder twice with hot water; and
remixing the cleaned and activated nickel powder with liquid
detergent.
48. The process of claim 46 wherein drying of the final
plated substrate material is by air drying at ambient
temperature and pressure.
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49. The process of claim 46 wherein the weight of
coating is from 15.0 to 25.0 weight percent, based on the
total weight of final noble metal-coated active non-noble
metal substrate material product.
50. The process of claim 46 wherein the weight of
coating is 16.0 weight percent, based on the total weight of
final noble metal-coated active non-noble metal substrate
material product; said first individual plating solution bath
is maintained at a temperature of about 75 °C; and said
second through fourth individual plating solution baths are
maintained at a temperature of about 100 °C.
51. A process for plating silver onto aluminum seeded
with copper according to claim 1, wherein said noble metal is
silver; said non-noble metal substrate material is aluminum
powder having spherical particles with a mean diameter of
from 5 to 15 microns, and which have been seeded with copper
atoms; the weight of coating is from 15 to 60 weight percent,
based on the total weight of final noble metal-coated
non-noble metal active substrate material product; said starter
plating solution is divided into 2 equal portions with 2 said
individual plating solution baths being prepared therefrom,
such that 50% of the total amount of free ions of noble metal
to be plated out is contained in each individual plating
solution bath; the first individual plating solution bath is
maintained at a temperature of from about 25 °C to about 35
°C; the second individual plating solution bath is maintained
at a temperature of from about 60 °C to about 70 °C; said
first series of water rinse steps is performed once and
comprises rinsing twice in succession with cold water; said
second series of rinse steps is repeated 4 times in
succession after completion of said first series of rinse
steps following plating in the second individual plating
solution bath, and comprises the sequence of steps of rinsing
once with hot water; rinsing once with a 25% glacial acetic
acid aqueous solution; rinsing a second time with hot water;
and rinsing once with methanol; said third series of rinse
steps is performed once and comprises the sequence of steps
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of rinsing 3 times with hot water, followed by rinsing 3
times with methanol; and said process further comprises the
initial steps, all performed before the first plating step,
of cleaning and activating the aluminum powder; seeding the
aluminum powder with copper atoms; and mixing the
copper-seeded aluminum powder with liquid detergent.
52. The process of claim 51 wherein cleaning and
activation of the aluminum powder comprises the step of
washing it with a sodium or potassium hydroxide solution.
53. The process of claim 52 wherein the sodium or
potassium hydroxide solution has a concentration of from 0.5
to 1.5 grams/liter.
54. The process of claim 51 wherein the initial step of
seeding aluminum powder with copper atoms is performed by
immersing the aluminum powder in a solution containing free
copper ions.
55. The process of claim 54 wherein the solution
containing free copper ions is an aqueous copper sulfate
solution.
56. The process of claim 55 wherein the copper sulfate
solution has a concentration of from 200 to 250 grams/gallon.
57. The process of claim 56 wherein the solution
further contains ammonium hydroxide and sodium or potassium
cyanide.
58. The process of claim 57 wherein ammonium hydroxide
is added to the aqueous copper sulfate solution in the amount
of 300 milliliters/gram.
59. The process of claim 57 wherein sodium or potassium
cyanide is added as aqueous sodium or potassium cyanide
solution having a concentration of from 170 to 180
grams/liter.
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60. The process of claim 51 wherein drying of the final
plated substrate material is by air drying at ambient
temperature and pressure.
61. The process of claim 54 wherein the weight of
coating is from 15.0 to 25.0 weight percent, based on the
total weight of final noble metal-coated active non-noble
metal substrate material product.
62. The process of claim 54 wherein the weight of
coating is 20.3 weight percent, based on the total weight of
final noble metal-coated active non-noble metal substrate
material product; said first individual plating solution bath
is maintained at a temperature of about 32 °C; and said
second individual plating solution bath is maintained at a
temperature of about 65 °C.
63. A process for plating gold onto nickel according to
claim 4, wherein said noble metal is gold; the source of the
free ions of the gold is potassium gold cyanide; said
non-noble metal substrate material is nickel powder having
spherical particles with a mean diameter of from 8 to 10
microns; the weight of coating is from 15 to 60 weight
percent, based on the total weight of final noble
metal-coated active non-noble metal substrate material product;
said starter plating solution is divided into 4 equal
portions with 4 said individual plating solution baths being
prepared therefrom, such that 25% of the total amount of free
ions of noble metal to be plated out is contained in the
first individual plating solution bath; 10% to 20% of the
total amount of free ions of noble metal to be plated out is
contained in each individual plating solution bath; the first
individual plating solution bath is maintained at a
temperature of from about 50 °C to about 80 °C; the second
through fourth individual plating solution baths are
maintained at a temperature of from about 85 °C to about 100
°C; said first series of water rinse steps comprises the
sequence of steps of rinsing twice with hot water; said
second series of rinse steps is repeated 4 times in
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succession after completion of said first series of water
rinse steps following plating in the fourth individual
plating solution bath, and comprises the sequence of steps of
rinsing once with hot water; rinsing once with a 25% glacial
acetic acid aqueous solution; rinsing a second time with hot
water; and rinsing once with methanol; said third series of
rinse steps is performed once and comprises the sequence of
steps of rinsing 3 times with hot water, followed by rinsing
3 times with methanol; and the process further comprises
cleaning and activating the nickel powder substrate material
prior to its immersion in said first individual plating
solution bath.
64. The process of claim 63 wherein cleaning and
activation of the nickel powder comprises the steps of first
mixing the nickel powder with liquid detergent to form a
paste; mixing the nickel powder paste with a sodium or
potassium cyanide activation solution; separating the cleaned
and activated nickel powder from the activation solution;
washing the activated nickel powder twice with hot water; and
remixing the cleaned and activated nickel powder with liquid
detergent.
65. The process of claim 63 wherein drying of the final
plated substrate material is by air drying at ambient
temperature and
pressure.
66. The process of claim 63 wherein the weight of
coating is from 15.0 to 25.0 weight percent, based on the
total weight of final noble metal-coated active non-noble
metal substrate material product.
67. The process of claim 63 wherein the weight of
coating is 16.0 weight percent, based on the total weight of
final noble metal-coated active non-noble metal substrate
material product; said first individual plating solution bath
is maintained at a temperature of about 75 °C; and said
second through fourth individual plating solution baths are
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maintained at a temperature of from about 94 °C to about 98
°C.
68. A composition comprising a noble metal plated onto
a non-noble metal substrate material, wherein:
said noble metal is selected from the group consisting
of silver, gold, platinum, palladium, iridium, rhodium,
ruthenium and osmium;
said non-noble metal substrate material is selected from
the group consisting of copper, nickel, aluminum, titanium,
zirconium, vanadium, hafnium, cadmium, niobium, tantalum,
molybdenum, tungsten, gallium, indium, and thallium;
said noble metal is present in said composition in an
amount of from about 2 percent by weight to about 60 percent
by weight; and
said non-noble metal substrate material is a powder
having an outer surface area;
such that said noble metal in said composition is
sufficient to at least completely coat said outer surface
area of said non-noble metal substrate material, leaving no
uncoated, exposed surface area.
69. The composition according to claim 68 wherein said
non-noble metal substrate material powder has spherical,
flake-shaped, or irregular-shaped particles.
70. The composition according to claim 69 wherein said
particles of said non-noble metal substrate material powder
have a mean diameter of from about 5 microns to about 15
microns.
71. The composition according to claim 68 wherein said
noble metal is present in said composition in an amount of
from about 15 percent by weight to about 25 percent by
weight.
72. The composition according to claim 68 wherein said
noble metal is silver and said non-noble metal substrate
material is copper.
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73. The composition according to claim 68 wherein said
noble metal is silver and said non-noble metal substrate
material is nickel.
74. The composition according to claim 68 wherein said
noble metal is gold and said non-noble metal substrate
material is nickel.
75. A composition comprising a noble metal plated onto
a non-noble metal substrate material, wherein:
said noble metal is selected from the group consisting
of silver, gold, platinum, palladium, iridium, rhodium,
ruthenium and osmium;
said non-noble metal substrate material is selected from
the group consisting of copper, nickel, aluminum, titanium,
zirconium, vanadium, hafnium, cadmium, niobium, tantalum,
molybdenum, tungsten, gallium, indium, and thallium;
said noble metal is present in said composition in an
amount of from about 2 percent by weight to about 60 percent
by weight;
said non-noble metal substrate material is a powder
having an outer surface area;
such that said noble metal present in said composition
is sufficient to at least completely coat said outer surface
area of said non-noble metal substrate material, leaving no
uncoated, exposed surface area;
and wherein said composition is produced by a process
comprising:
a) preparing a starter aqueous plating solution
containing an amount of free ions of a noble metal to be
plated out onto said non-noble metal substrate material,
such that said amount of free ions of said noble metal is
sufficient to plate said non-noble metal substrate material
with a coating of from 2 to 60 weight percent, based on the
total weight of a final noble metal-coated non-noble metal
substrate material product, and such that said amount of free
ions of said noble metal plated onto said non-noble metal
substrate material is sufficient to at least provide a
coating on the surface of said non-noble metal substrate
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material that completely covers the entire surface of said
non-noble metal substrate material, leaving no exposed
surface of said non-noble metal substrate material;
b) dividing said starter plating solution, prepared in
(a), into a plurality of portions, such that each portion of
said starter plating solution contains a percentage amount of
from less than about 1% to about 85%, by weight, of the total
amount of free ions of noble metal to be plated out that are
contained in said starter plating solution, the percentage
amount that is present in any said portion being the same as
or different from the percentage amount present in other of
said portions;
c) preparing a plurality of individual plating
solution baths into which said non-noble metal substrate
material is immersible, by selecting a concentration of free
ions of noble metal for each said plating solution bath which
is to be made from a corresponding one of said plurality of
portions of said starter plating solution, prepared in (b),
said concentration of free ions of noble metal for each said
individual plating solution bath being in the range of from
about 0.3 to about 65 grams of free ions of noble metal per
liter of plating solution bath, and making each said
individual plating solution bath by adding water to each
corresponding one of said plurality of portions of said
starter plating solution, to increase the volume thereof,
such that each one of said plurality of individual plating
solution baths has the concentration of free ions of noble
metal, as selected above therefor;
d) immersing an amount of a non-noble metal substrate
material to be plated into one of said individual plating
solution baths, prepared in (c), which is maintained at a
temperature in the range of from about 20 °C to about 100 °C,
such that the temperature of said individual plating solution
bath is inversely related to the oxidation potential of the
non-noble metal substrate material being plated, to cause
said free ions of noble metal to plate-out onto said
substrate material until said one of said individual plating
solution baths is depleted of all but a trace amount of said
free noble metal ions contained therein, thereby forming an
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intermediate plated substrate material on which is plated the
fraction of free ions of noble metal contained in said one of
said individual plating solution baths;
e) separating said intermediate plated substrate
material, prepared in (d), from the depleted plating solution
bath;
f) rinsing said intermediate plated substrate
material, separated in (e), at least once with a first series
of water rinses;
g) repeating (d), (e), and (f) with the rinsed
intermediate plated substrate material resulting from each
previous sequence of (d), (e), and (f), and another one of
said individual plating solution baths, until all of said
individual plating solution baths prepared according to (c)
have been utilized, the sequence of utilization of said
individual plating solution baths being such that when the
concentration of free noble-metal ions in at least two of
said individual plating solution baths is different, said
individual plating solution baths are successively utilized
in the order of decreasing concentration of free ions of
noble metal therein, and further such that the temperature of
each successively utilized individual plating solution bath
is at least as high as the temperature of the preceding
individual plating solution bath, thereby forming further
intermediate plated substrate materials with each repetition
of the sequence of (d), (e) and (f), such that each
successive intermediate plated substrate material is
cumulatively plated with the amounts of free ions of noble
metal contained in each of the plating solution baths into
which the intermediate plated substrate material has been
immersed, thereby ultimately forming a final plated substrate
material, onto which has been plated the total said amount of
free ions of noble metal in said original starter plating
solution;
h) rinsing said final plated substrate material,
prepared in (g), at least once with a second series of
rinses, including rinses with water, an acid, and an alcohol;
i) further rinsing said final plated substrate
material, as rinsed according to (h), at least once with a
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third series of rinses, including rinses with water, and an
alcohol; and
j) drying said final plated substrate material, as
rinsed according to (i), to produce a final noble
metal-coated non-noble metal substrate material product.
76. The composition according to claim 75 wherein a
first portion of the plurality of portions into which said
starter plating solution is divided contains from about 20%
to about 85%, by weight, of the total amount of free ions of
noble metal to be plated out, contained in said starter
plating solution; a second portion of the plurality of
portions into which said starter plating solution is divided
contains from about 15% to about 55%, by weight, of the total
amount of free ions of noble metal to be plated out,
contained in said starter plating solution; where a third
portion is utilized, said third portion contains from about
1% to about 30%, by weight, of the total amount of free ions
of noble metal to be plated out, contained in said starter
plating solution; where a fourth portion is utilized, said
fourth portion contains from about 0.1% to about 30%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; and
where a fifth or subsequent portion is utilized, each of said
fifth and subsequent portions contains less than about 1%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; such
that the sum of the percentages in all of the portions is
100%.
77. The composition according to claim 75 wherein said
process further comprises repeating said first series of
water rinses, according to (f), once, after completion of the
first series of rinses, which follows immersion of the plated
substrate material in the individual plating solution bath in
which the substrate material is plated with the percentage of
free ions of noble metal cumulatively amounting to at least
85% of the total amount of free ions of noble metal to be
plated out, with there then remaining at least one more
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plating solution bath in which plating of the remaining
percentage of free ions of noble metal onto the substrate
material is completed.
78. A silver-plated copper powder produced according to
claim 77 wherein said noble metal is silver; said non-noble
metal substrate material is copper powder having spherical
particles with a mean diameter of from 5 to 15 microns; the
weight of silver coating plated onto said copper powder is
from 15 to 60 weight percent, based on the total weight of
final noble metal-coated non noble metal substrate material
product; said starter plating solution is divided into 5
portions with 5 said individual plating solution baths being
prepared therefrom, such that from about 75% to about 85% of
the total amount of free ions of noble metal to be plated out
onto said substrate is contained in the first individual
plating solution bath; from about 10% to about 20% of the
total amount of free ions of noble metal to be plated out
onto said substrate is contained in the second individual
plating solution bath; from about 1% to about 5% of the total
amount of free ions of noble metal to be plated out onto said
substrate is contained in the third individual plating
solution bath; and from about 0.1% to about 0.5% of the total
amount of free ions of noble metal to be plated out onto said
substrate is contained in each of the fourth and fifth
individual plating solution baths, such that the total of all
percentages of amounts of free ions of noble metal to be
plated out in the 5 baths is 100%; the first individual
plating solution bath is maintained at a temperature of from
about 50 °C to about 80 °C; the second through fifth
individual plating solution baths are maintained at a
temperature of from about 85 °C to about 100 °C ; said first
series of water rinses is performed once and comprises the
sequence of rinsing once with warm water, followed by rinsing
once with hot water; said second series of rinses is repeated
4 times in succession after completion of the first series of
water rinses following plating in the fifth individual
plating solution bath, with each repetition comprising the
four-part sequence of rinsing once with hot water, rinsing
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once with a 25% glacial acetic acid aqueous solution, rinsing
a second time with hot water, and rinsing once with methanol;
said third series of rinses is performed once immediately
after completion of the final repetition of said second
series of rinses and comprises the sequence of rinsing 3
times with hot water, followed by rinsing 3 times with
methanol; and said process further comprises performing the
four-part sequence of said second series of rinses once,
after completion of the first series of rinses which follows
after plating in the third individual plating solution
bath.
79. The silver-plated copper powder according to claim
78 wherein the weight of silver plating coated onto said
copper powder is from 15.0 to 25.0 weight percent, based on
the total weight of final noble metal coated non-noble metal
substrate material product.
80. The silver-plated copper powder according to claim
78 wherein the weight of silver plating coated onto said
copper powder is 17.6 weight percent, based on the total
weight of final noble metal coated non-noble metal substrate
material product, and 80% of the total amount of free ions of
silver to be plated out onto said copper powder is contained
in the first individual plating solution bath; 16% of the
total amount of free ions of silver to be plated out onto
said copper powder is contained in the second individual
plating solution bath; 3.2% of the total amount of free ions
of silver to be plated out onto said copper powder is
contained in the third individual plating solution bath; and
0.4% of the total amount of free ions of silver to be plated
out onto said copper powder is contained in each of the
fourth and fifth individual plating solution baths.
81. A silver-plated nickel powder produced according to
claim 75 wherein said noble metal is silver; said non-noble
metal substrate material is nickel powder having spherical
particles with a mean diameter of from 5 to 15 microns; the
weight of silver coating plated onto said nickel powder is
- 91 -
from 15 to 60 weight percent, based on the total weight of
final noble metal coated non-noble metal substrate material
product; said starter plating solution is divided into 4
equal portions with 4 said individual plating solution baths
being prepared therefrom, such that 25% of the total amount
of free ions of noble metal to be plated out is contained in
each individual plating solution bath; the first individual
plating solution bath is maintained at a temperature of from
about 50 °C to about 80 °C; the second through fourth
individual plating solution baths are maintained at a
temperature of from about 85 °C to about 100 °C; said first
series of water rinses comprises the sequence of rinsing
twice with hot water; said second series of rinses is
repeated 4 times in succession after completion of said first
series of water rinses following plating in the fourth
individual plating solution bath, and comprises the sequence
of rinsing once with hot water; rinsing once with a 25%
glacial acetic acid aqueous solution; rinsing a second time
with hot water; and rinsing once with methanol; said third
series of rinses. is performed once and comprises the sequence
of rinsing 3 times with hot water, followed by rinsing 3
times with methanol; and said process further comprises
cleaning and activating said nickel powder substrate material
prior to its immersion in the first individual plating
solution bath.
82. The silver-plated nickel powder according to claim
81 wherein the weight of silver plating coated onto said
nickel powder is from 15.0 to 25.0 weight percent, based on
the total weight of final noble metal-coated non-noble metal
substrate material product.
83. The silver-plated nickel powder according to claim
81 wherein the weight of silver plating coated onto said
nickel powder is 16.0 weight percent, based on the total
weight of final noble metal-coated non-noble metal substrate
material product; said first individual plating solution bath
is maintained at a temperature of about 75 °C; and said
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second through fourth individual plating solution baths are
maintained at a temperature of about 100 °C.
84. A gold-plated nickel powder produced according to
claim 75 wherein said noble metal is gold; said non-noble
metal substrate material is nickel powder having spherical
particles with a mean diameter of from 5 to 15 microns; the
weight of gold coating plated onto said nickel powder is from
15 to 60 weight percent, based on the total weight of final
noble metal coated non-noble metal substrate material
product; said starter plating solution is divided into 4
equal portions with 4 said individual plating solution baths
being prepared therefrom, such that 25% of the total amount
of free ions of noble metal to be plated out is contained in
each individual plating solution bath; the first individual
plating solution bath is maintained at a temperature of from
about 50 °C to about 80 °C; the second through fourth
individual plating solution baths are maintained at a
temperature of from about 85 °C to about 100 °C; said first
series of water rinses comprises the sequence of rinsing
twice with hot water; said second series of rinses is
repeated 4 times in succession after completion of said first
series of water rinses following plating in the fourth
individual plating solution bath, and comprises the sequence
of rinsing once with hot water; rinsing once with a 25%
glacial acetic acid aqueous solution; rinsing a second time
with hot water; and rinsing once with methanol; said third
series of rinses is performed once and comprises the sequence
of rinsing 3 times with hot water, followed by rinsing 3
times with methanol; and said process further comprises
cleaning and activating said nickel powder substrate material
prior to its immersion in the first individual plating
solution bath.
85. The gold-plated nickel powder according to claim 84
wherein the weight of gold plating coated onto said nickel
powder is from 15.0 to 25.0 weight percent, based on the
total weight of final noble metal-coated non-noble metal
substrate material product.
- 93 -
86. The gold-plated nickel powder according to claim 84
wherein the weight of gold plating coated onto said nickel
powder is 16.0 weight percent, based on the total weight of
final noble metal-coated non-noble metal substrate material
product; said first individual plating solution bath is
maintained at a temperature of about 75 °C; and said second
through fourth individual plating solution baths are
maintained at a temperature of about 100 °C.
87. An electrically conductive composition comprising
a noble metal-coated, non-noble metal substrate material
powder, wherein said noble metal is selected from the group
consisting of silver, gold, and platinum, said non-noble
metal substrate material powder is selected from the group
consisting of copper, nickel, aluminum, titanium, zirconium,
vanadium, hafnium, cadmium, niobium, tantalum, molybdenum,
tungsten, gallium, indium, and thallium; such that individual
particles of said non-noble metal substrate material powder
have a mean diameter of from about 5 microns to about 15
microns, and an outer surface area, with said non-noble metal
substrate material powder being coated with said noble metal,
such that said noble metal is in an amount of from about 2
percent by weight to about 60 percent by weight, based on the
total weight of the composition, and further such that said
noble metal in said composition is present in an amount
sufficient to at least completely coat said outer surface
area of said non-noble metal substrate material powder,
leaving no exposed outer surface area of said non-noble metal
substrate material powder uncoated with said noble metal.
88. A composition comprising a noble metal plated onto
a non-noble metal substrate material, wherein:
said noble metal is selected from the group consisting
of silver, gold, platinum, palladium, iridium, rhodium,
ruthenium, and osmium;
said non-noble metal substrate material is a first
non-noble metal selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
-94-
indium, and thallium, seeded with atoms of a second non-noble
metal selected from the group consisting of copper, nickel,
aluminum, titanium, zirconium, vanadium, hafnium, cadmium,
niobium, tantalum, molybdenum, tungsten, gallium, indium, and
thallium, such that said first non-noble metal and said
second non-noble metal of said non-noble metal substrate
material are different and further such that said noble metal
has a greater affinity for plating-out onto said second
non-noble metal than for plating-out onto said first non-noble
metal;
said noble metal is present in said composition in an
amount of from about 2 percent by weight to about 60 percent
by weight, based on the total weight of the composition; and
said non-noble metal substrate material is a powder
having an outer surface area;
such that said noble metal in said composition is
sufficient to at least completely coat said outer surface
area of said non-noble metal substrate material, leaving no
uncoated, exposed surface area.
89. The composition according to claim 88 wherein said
non-noble metal substrate material powder has spherical,
flake-shaped, or irregular-shaped particles.
90. The composition according to claim 89 wherein said
non-noble metal substrate material powder has spherical
particles.
91. The composition according to claim 89 wherein said
particles of said non-noble metal substrate material powder
have a mean diameter of from about 5 microns to about 15
microns.
92. The composition according to claim 88 wherein said
noble metal is present in said composition in an amount of
from about 15 percent by weight to about 25 percent by
weight.
.
-95-
93. The composition according to claim 88 wherein said
noble metal is silver, said first non-noble metal of said
non-noble metal substrate material is aluminum, and said
second non-noble metal of said non-noble metal substrate
material is copper.
94. The composition according to claim 88 wherein said
noble metal is gold and said first non-noble metal of said
non-noble metal substrate material is aluminum, and said
second non-noble metal of said non-noble metal substrate
material is copper.
95. The composition according to claim 88 wherein said
noble metal is platinum and said first non-noble metal of
said non-noble metal substrate material is aluminum, and said
second non-noble metal of said non-noble metal substrate
material is copper.
96. A composition comprising a noble metal plated onto
a non-noble metal substrate material, wherein:
said noble metal is selected from the group consisting
of silver, gold, platinum, palladium, iridium, rhodium,
ruthenium and osmium;
said non-noble metal substrate material is a first
non-noble metal selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, and thallium, seeded with atoms of a second non-noble
metal selected from the group consisting of copper, nickel,
aluminum, titanium, zirconium, vanadium, hafnium, cadmium,
niobium, tantalum, molybdenum, tungsten, gallium, indium, and
thallium, such that said first non-noble metal and said
second non-noble metal of said non-noble metal substrate
material are different and further such that said noble metal
has a greater affinity for plating-out onto said second
non-noble metal than for plating-out onto said first non-noble
metal;
-96-
said noble metal is present in said composition in an
amount of from about 2 percent by weight to about 60 percent
by weight;
said non-noble metal substrate material is a powder
having an outer surface area;
such that said noble metal present in said composition
is sufficient to at least completely coat said outer surface
area of said non-noble metal substrate material, leaving no
uncoated, exposed surface area;
and wherein said composition is formed by the process
of:
a) seeding said first non-noble metal of said
substrate material with atoms of said second non-noble metal
of said substrate material;
b) preparing a starter aqueous plating solution
containing an amount of free ions of a noble metal to be
plated out onto said non-noble metal substrate material,
such that said amount of free ions of said noble metal is
sufficient to plate said non-noble metal substrate material
with a coating of from 2 to 60 weight percent, based on the
total weight of a final noble metal-coated active non-noble
metal substrate material product, and such that said amount
of free ions of said noble metal plated onto said active
non-noble metal substrate material is sufficient to at least
provide a coating on the surface of said active non-noble
metal substrate material that completely covers the entire
surface of said active non-noble metal substrate material,
leaving no exposed surface of said active non-noble metal
substrate material, and combinations of a first one of said
non-noble metal substrate materials seeded with atoms of a
second one of said non-noble metal substrate materials having
a greater affinity than that of said first non-noble metal
substrate material for said selected noble metal to be plated
thereon;
c) dividing said starter plating solution, prepared in
(b), into a plurality of portions, such that each portion of
said starter plating solution contains a percentage amount of
from less than about 1% to about 85%, by weight, of the total
amount of free ions of noble metal to be plated out that are
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contained in said starter plating solution, the percentage
amount that is present in any said portion being the same as
or different from the percentage amount present in other of
said portions;
d) preparing a plurality of individual plating
solution baths into which said active non-noble metal
substrate material is immersible, by selecting a
concentration of free ions of noble metal for each said
plating solution bath which is to be made from a
corresponding one of said plurality of portions of said
starter plating solution, prepared in (c), said concentration
of free ions of noble metal for each said individual plating
solution bath being in the range of from about 0.3 to about
65 grams of free ions of noble metal per liter of plating
solution bath, and making each said individual plating
solution bath by adding water to each corresponding one of
said plurality of portions of said starter plating solution,
to increase the volume thereof, such that each one of said
plurality of individual plating solution baths has the
concentration of free ions of noble metal, as selected above
therefor;
e) immersing an amount of said active non-noble metal
substrate material of a first noble metal seeded with atoms
of a second noble metal, which non-noble metal substrate
material is to be plated, into one of said individual plating
solution baths, prepared in (d), which is maintained at a
temperature in the range of from about 20 °C to about 100 °C,
to cause said free ions of noble metal to plate-out onto said
substrate material until said one of said individual plating
solution baths is depleted of all but a trace amount of said
free noble metal ions contained therein, thereby forming an
intermediate plated substrate material on which is plated the
fraction of free ions of noble metal contained in said one of
said individual plating solution baths;
f) separating said intermediate plated substrate
material, prepared in (e), from the depleted plating solution
bath;
g) rinsing said intermediate plated substrate
material, separated in (f), at least once with a first series
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of water rinses wherein each series of rinses includes a
sequence of steps selected from the group (i - iii)
consisting of (i) rinsing twice in succession with cold
water, (ii) rinsing once with warm water, followed by rinsing
once with hot water, and (iii) rinsing twice in succession
with hot water;
h) repeating (e), (f), and (g) with the rinsed
intermediate plated substrate material resulting from each
previous sequence of (e), (f), and (g), and another one of
said individual plating solution baths, until all of said
individual plating solution baths prepared according to (d)
have been utilized, the sequence of utilization of said
individual plating solution baths being such that when the
concentration of free noble-metal ions in at least two of
said individual plating solution baths is different, said
individual plating solution baths are successively utilized
in the order of decreasing concentration of free ions of
noble metal therein, and further such that the temperature of
each successively utilized individual plating solution bath
is at least as high as the temperature of the preceding
individual plating solution bath, thereby forming further
intermediate plated substrate materials with each repetition
of the sequence or (e), (f) and (g), such that each
successive intermediate plated substrate material is
cumulatively plated with the amounts of free ions of noble
metal contained in each of the plating solution baths into
which the intermediate plated substrate material has been
immersed, thereby ultimately forming a final plated substrate
material, onto which has been plated the total said amount of
free ions of noble metal in said original starter plating
solution;
i) rinsing said final plated substrate material,
prepared in (h), at least once with a second series of
rinses, wherein each of said second series of rinses includes
successive rinses with water, an acid, and an alcohol;
j) further rinsing said final plated substrate
material, as rinsed according to (i), at least once with a
third series of rinses, wherein each of said third series of
rinses includes from 1 to 3 successive rinses with hot water,
-99-
followed by from 1 to 3 successive rinses with an alcohol;
and
k) drying said final plated substrate material, as
rinsed according to (j), to produce a final noble metal-coated
active non-noble metal substrate material product.
97. The composition according to claim 96 wherein a
first portion of the plurality of portions into which said
starter plating solution is divided contains from about 20%
to about 85%, by weight, of the total amount of free ions of
noble metal to be plated out, contained in said starter
plating solution; a second portion of the plurality of
portions into which said starter plating solution is divided
contains from about 15% to about 55%, by weight, of the total
amount of free ions of noble metal to be plated out,
contained in said starter plating solution; where a third
portion is utilized, said third portion contains from about
1% to about 30%, by weight, of the total amount of free ions
of noble metal to be plated out, contained in said starter
plating solution; where a fourth portion is utilized, said
fourth portion contains from about 0.1% to about 30%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; and
where a fifth or subsequent portion is utilized, each of said
fifth and subsequent portions contains less than about 1%, by
weight, of the total amount of free ions of noble metal to be
plated out, contained in said starter plating solution; such
that the sum of the percentages in all of the portions is
100%.
98. A composition according to claim 97 wherein said
starter plating solution is divided into two portions, each
of which contains 50%, by weight, of the total amount of free
ions of noble metal to be plated out, contained in said
starter plating solution.
- 100 -
99. A composition according to claim 96 wherein when
said first non-noble metal of said non-noble metal substrate
material is aluminum having an oxide coating on the surface
thereof, said aluminum is first made active by removing said
oxide coating.
100. A silver-plated copper-seeded aluminum powder
according to claim 96 wherein said noble metal is silver;
said non-noble metal substrate material is aluminum powder
having spherical particles with a mean diameter of from 5 to
15 microns, which has been seeded with copper atoms; the
weight of silver plating coated onto said copper-seeded
aluminum powder is from 15 to 60 weight percent, based on the
total weight of final silver-plated copper-seeded aluminum
powder product; said starter plating solution is divided into
2 equal portions with 2 said individual plating solution
baths being prepared therefrom, such that 50% of the total
amount of free ions of noble metal to be plated out is
contained in each individual plating solution bath; the first
individual plating solution bath is maintained at a
temperature of from about 25 °C to about 35 °C; the second
individual plating solution bath is maintained at a
temperature of from about 60 °C to about 70 °C; said first
series of water rinses is performed once and comprises
rinsing twice in succession with cold water; said second
series of rinses is repeated 4 times in succession after
completion of said first series of rinses following plating
in the second individual plating solution bath, and comprises
the sequence of rinsing once with hot water; rinsing once
with a 25% glacial acetic acid aqueous solution; rinsing a
second time with hot water; and rinsing once with methanol;
said third series of rinses is performed once and comprises
the sequence of rinsing 3 times with hot water, followed by
rinsing 3 times with methanol; and said process further
comprises initially performing, before said first plating, a
cleaning and activating of said aluminum powder; seeding said
aluminum powder with copper atoms; and mixing the copper-seeded
aluminum powder with liquid detergent.
-101-
101. The silver-plated copper-seeded aluminum powder
according to claim 100 wherein the weight of silver plating
coated onto said copper-seeded aluminum powder is from 15.0
to 25.0 weight percent, based on the total weight of final
silver-plated copper-seeded aluminum powder product.
102. The silver-plated copper-seeded aluminum powder
according to claim 100 wherein the weight of silver plating
coated onto said copper-seeded aluminum powder is 20.3 weight
percent, based on the total weight of final silver-plated
copper-seeded aluminum powder product; said first individual
plating solution bath is maintained at a temperature of about
32 °C; and said second individual plating solution bath is
maintained at a temperature of about 65 °C.
103. A gold-plated copper-seeded aluminum powder
according to claim 96 wherein said noble metal is gold; said
non-noble metal substrate material is aluminum powder having
spherical particles with a mean diameter of from 5 to 15
microns, which has been seeded with copper atoms; the weight
of gold plating coated onto said copper-seeded aluminum
powder is from 15 to 60 weight percent, based on the total
weight of final gold-plated copper-seeded aluminum powder
product; said starter plating solution is divided into 2
equal portions with 2 said individual plating solution baths
being prepared therefrom, such that 50% of the total amount
of free ions of noble metal to be plated out is contained in
each individual plating solution bath; the first individual
plating solution bath is maintained at a temperature of from
about 25 °C to about 35 °C; the second individual plating
solution bath is maintained at a temperature of from about 60
°C to about 70 °C; said first series of water rinses is
performed once and comprises rinsing twice in succession with
cold water; said second series of rinses is repeated 4 times
in succession after completion of said first series of rinses
following plating in the second individual plating solution
bath, and comprises the sequence of rinsing once with hot
water; rinsing once with a 25% glacial acetic acid aqueous
solution; rinsing a second time with hot water; and rinsing
-102-
once with methanol; said third series of rinses is performed
once and comprises the sequence of rinsing 3 times with hot
water, followed by rinsing 3 times with methanol; and said
process further comprises initially performing, before said
first plating, a cleaning and activating of said aluminum
powder; seeding said aluminum powder with copper atoms; and
mixing the copper-seeded aluminum powder with liquid
detergent.
104. The gold-plated copper-seeded aluminum powder
according to claim 103 wherein the weight of gold plating
coated onto said copper-seeded aluminum powder is from 15.0
to 25.0 weight percent, based on the total weight of final
gold-plated copper-seeded aluminum powder product.
105. A platinum-plated copper-seeded aluminum powder
according to claim 96 wherein said noble metal is platinum;
said non-noble metal substrate material is aluminum powder
having spherical particles with a mean diameter of from 5 to
15 microns, which has been seeded with copper atoms; the
weight of platinum plating coated onto said copper-seeded
aluminum powder is from 15 to 60 weight percent, based on the
total weight of final platinum-plated copper-seeded aluminum
powder product; said starter plating solution is divided into
2 equal portions with 2 said individual plating solution
baths being prepared therefrom, such that 50% of the total
amount of free ions of noble metal to be plated out is
contained in each individual plating solution bath; the first
individual plating solution bath is maintained at a
temperature of from about 25 °C to about 35 °C; the second
individual plating solution bath is maintained at a
temperature of from about 60 °C to about 70 °C; said first
series of water rinses is performed once and comprises
rinsing twice in succession with cold water; said second
series of rinses is repeated 4 times in succession after
completion of said first series of rinses following plating
in the second individual plating solution bath, and comprises
the sequence of rinsing once with hot water; rinsing once
with a 25% glacial acetic acid aqueous solution; rinsing a
-103-
second time with hot water; and rinsing once with methanol;
said third series of rinses is performed once and comprises
the sequence of rinsing 3 times with hot water, followed by
rinsing 3 times with methanol; and said process further
comprises initially performing, before said first plating, a
cleaning and activating of said aluminum powder; seeding said
aluminum powder with copper atoms; and mixing the copper-seeded
aluminum powder with liquid detergent.
106. The platinum-plated copper-seeded aluminum powder
according to claim 105 wherein the weight of platinum plating
coated onto said copper-seeded aluminum powder is from 15.0
to 25.0 weight percent, based on the total weight of final
platinum-plated copper-seeded aluminum powder product.
107. An electrically conductive composition comprising
a noble metal-coated, copper-seeded aluminum powder, with
aluminum particles having a mean diameter of from about 5
microns to about 15 microns, and an outer surface area, with
said aluminum powder containing copper in an amount of from
about 0.001 percent by weight to about 0.01 percent by
weight, based on the weight of aluminum powder, with said
copper-seeded aluminum powder being coated with a noble metal
selected from the group consisting of silver, gold, and
platinum, said noble metal being in an amount of from about
2 percent by weight to about 60 percent by weight, based on
the total weight of the composition; such that said noble
metal in said composition is present in an amount sufficient
to at least completely coat said outer surface area of said
copper-seeded aluminum powder, leaving no exposed surface
area of said copper-seeded aluminum powder uncoated with said
noble metal.
108. The composition according to claim 88 wherein said
non-noble metal substrate material containing a first
non-noble metal seeded with atoms of a second non-noble metal is
a solid solution of said first non-noble metal and said
second non-noble metal, such that said solid solution is
composed of a solid solute and a solid solvent, wherein said
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first non-noble metal is said solvent of said solid solution
and said second non-noble metal is said solute of said solid
solution.
109. The composition according to claim 108 wherein said
solid solution of said first non-noble metal and said second
non-noble metal is a substitutional solid solution when atoms
of said second non-noble metal have a diameter which is
substantially the same size as the diameter of atoms of said
first non-noble metal; and wherein said solid solution of
said first non-noble metal and said second non-noble metal is
an interstitial solid solution when atoms of said second
non-noble metal have a diameter which is less than about 59% of
the diameter of atoms of said first non-noble metal.
110. The composition according to claim 88 wherein said
second non-noble metal constitutes from about 0.001 to about
0.01 weight percent of said non-noble metal substrate
material.
111. The composition according to claim 96 wherein in
(e) the temperature of said individual plating solution bath
is inversely related to the oxidation potential of the
non-noble metal substrate material being plated;
with the temperature of a first individual plating
solution bath being at up to about 32 °C when said first
non-noble metal of said non-noble metal substrate material is
aluminum;
with the temperature of a first individual plating
solution bath being at up to about 70 °C when said first
non-noble metal of said non-noble metal substrate material is
copper; and
with the temperature of a first individual plating
solution bath being at up to about 80 °C when said first
non-noble metal of said non-noble metal substrate material is
nickel.
-105-
112. The process according to claim 96 wherein in (e)
the temperatures of said individual plating solution baths
are inversely related to the oxidation potential of the
non-noble metal substrate material being plated, with a lower
temperature within said range being selected when said
non-noble metal substrate material has a high oxidation
potential, and a higher temperature within said range being
selected when said non-noble metal substrate material has a
low oxidation potential.
113. The composition according to claim 96 wherein in
(e) the temperature of a first individual plating solution
bath is:
at up to about 32 °C when said first non-noble metal of
said non-noble metal substrate material is aluminum;
at up to about 70 °C when said first non-noble metal of
said non-noble metal substrate material is copper; and
at up to about 80 °C when said first non-noble metal of
said non-noble metal substrate material is nickel.
114. The composition according to claim 96 wherein in
(a) the seeding of said first non-noble metal of said
substrate material with atoms of said second non-noble metal
of said substrate material is performed by washing said first
non-noble metal with a liquid solution containing atoms of
said second non-noble metal, such that substantially all of
said atoms of said second non-noble metal come out of said
liquid solution leaving a lean solution, followed by
decanting of said lean solution, to produce a dual non-noble
metal substrate in which said atoms of said second non-noble
metal are seeded among said first non-noble metal.
115. The composition according to claim 96 wherein said
non-noble metal substrate material containing a first
non-noble metal seeded with atoms of a second non-noble metal is
a solid solution of said first non-noble metal and said
second non-noble metal, such that said solid solution is
composed of a solid solute and a solid solvent, wherein said
first non-noble metal is said solvent of said solid solution
-106-
and said second non-noble metal is said solute of said solid
solution.
116. The composition according to claim 115 wherein said
solid solution of said first non-noble metal and said second
non-noble metal is a substitutional solid solution when atoms
of said second non-noble metal have a diameter which is
substantially the same size as the diameter of atoms of said
first non-noble metal; and wherein said solid solution of
said first non-noble metal and said second non-noble metal is
an interstitial solid solution when atoms of said second
non-noble metal have a diameter which is less than about 59% of
the diameter of atoms of said first non-noble metal.
117. The composition according to claim 96 wherein said
second non-noble metal constitutes from about 0.001 to about
0.01 weight percent of said non-noble metal substrate
material.
118. The silver-plated copper-seeded aluminum powder
according to claim 100 wherein said copper constitutes from
about 0.001 to about 0.01 weight percent of said copper-seeded
aluminum powder.
119. The gold-plated copper-seeded aluminum powder
according to claim 103 wherein said copper constitutes from
about 0.001 to about 0.01 weight percent of said copper-seeded
aluminum powder.
120. The platinum-plated copper-seeded aluminum powder
according to claim 105 wherein said copper constitutes from
about 0.001 to about 0.01 weight percent of said copper-seeded
aluminum powder.
121. A noble metal plated non-noble substrate produced
according to the process of claim 1.
122. A silver plated copper powder produced according to
the process of claim 42.
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123. A silver plated copper powder produced according to
the process of claim 45.
124. A silver plated nickel powder produced according to
the process of claim 46.
125. A silver plated nickel powder produced according to
the process of claim 50.
126. A silver plated copper-seeded aluminum powder
produced according to the process of claim 51.
127. A silver plated copper-seeded aluminum powder
produced according to the process of claim 62.
128. A gold plated nickel powder produced according to
the process of claim 63.
129. A gold plated nickel powder produced according to
the process of claim 67.
130. A coated metal powder comprising aluminum powder
seeded with an effective amount of a different non-noble
seeding metal having a greater affinity for a noble metal
with which the seeded aluminum powder is coated than for said
aluminum powder, such that the seeded aluminum powder is
completely covered with the noble metal.
131. The coated metal powder according to claim 130
wherein the aluminum powder has spherical-shaped particles
with a mean diameter of from 5 to 15 microns.
132. The coated metal powder according to claim 130
wherein the noble metal is selected from the group consisting
of silver, gold and platinum.
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133. The coated metal powder according to claim 130
wherein the noble metal coating the seeded aluminum powder is
in an amount of from 2 to 60 weight percent, based on the
final total weight of the coated powder.
134. The coated metal powder according to claim 130
wherein the seeding metal is present in an amount of at least
0.001 weight percent, based on the weight of aluminum.
135. The coated metal powder according to claim 130
wherein the seeding metal is copper.
136. The coated metal powder according to claim 130
wherein the seeding metal is copper, in an amount of about
0.05 weight percent, based on the weight of aluminum, and the
noble metal is silver, in an amount of from about 15 to about
25 weight percent, based on the final total weight of the
coated powder.
137. Silver-coated, copper-seeded aluminum powder.
138. An electromagnetic interference shielding material
comprising:
a matrix material filled with a noble metal plated
non-noble metal substrate,
wherein the noble metal plated non-noble metal substrate
is produced by the electroless deposition of the noble metal,
selected from the group consisting of silver, gold, platinum,
palladium, irridium, rhodium, ruthenium and osmium, onto the
substrate, selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, thalium and combinations of a principal one of the
foregoing substrate materials seeded with atoms of another
one of the foregoing substrate materials having a greater
affinity than the principal substrate material for the noble
metal being plated thereon,
from a plurality of aqueous solution plating baths
prepared by division into said plurality of baths of a
-109-
starter aqueous plating solution containing a total quantity
of free noble metal ions sufficient to plate the non-noble
metal substrate with a selected amount of noble metal coating
of from 2-60 percent of the total weight of final coated
substrate, such that each of said plurality of baths contains
a specified fraction of the total amount of free noble metal
ions to be deposited, and is brought to a specified
concentration by the addition of water thereto;
and further wherein the free noble metal ions are
deposited onto the substrate from a first one of the plating
solution baths maintained at a temperature in the range of
from about 20 °C to about 100 °C, until the plating solution
bath is substantially depleted of free noble metal ions,
thereby forming a first intermediate plated substrate which
is separated from the depleted plating solution bath, rinsed
at least once with a first series of rinse steps selected
from the group consisting of rinsing twice in succession with
cold water; rinsing once with warm water, followed by rinsing
once with hot water; and rinsing twice in succession with hot
water;
the final plated substrate, coated with the total amount
of noble metal ions in the original starter plating solution,
is prepared by repeating the deposition, separation and first
rinsing sequence steps with the intermediate plated substrate
from the previous sequence of steps to form a next plated
substrate, cumulatively plated with the fractions of noble
metal ions contained in the subsequent plating solution baths
into which the substrate has been immersed, until all of said
plating solution baths have been utilized;
the final plated substrate then being rinsed at least
once with a second series of rinse steps, including rinsing
once with hot water, rinsing once with a weak acid selected
from the group consisting of aqueous solutions of glacial
acetic acid, dilute hydrochloric acid, dilute nitric acid,
and hydrazine; rinsing a second time with hot water, and
rinsing once with an alcohol selected from the group
consisting of lower alkanols having from 1 to 4 carbon atoms;
rinsing at least once with a third series of rinse steps
including rinsing from 1 to 3 times in succession with hot
-110-
water, followed by rinsing from 1 to 3 times in succession
with an alcohol selected from the group consisting of lower
alkanols having from 1 to 4 carbon atoms; and
drying to form the final noble metal plated non-noble
metal substrate for use in the shielding material.
139. The electromagnetic interference shielding material
of claim 138 wherein the matrix material is selected from the
group consisting of a rubber, a plastic material, an elastic
material and mixtures thereof.
140. The electromagnetic interference shielding material
of claim 139 wherein the elastic material is a silicone, a
fluorosilicone or a polyisobutylene elastomer; and the
plastic material is a polyamide, an acrylic, a urethane, or
a polyvinyl chloride silicone plastic.
141. The electromagnetic interference shielding material
according to claim 140 wherein the noble metal plated
non-noble metal substrate is a silver plated copper powder.
142. The electromagnetic interference shielding material
according to claim 140 wherein the noble metal plated
non-noble metal substrate is a silver plated nickel powder.
143. An electromagnetic interference shielding material
comprising a matrix material selected from the group
consisting of a rubber, a plastic material, an elastic
material and mixtures thereof, which is filled with an amount
of a silver plated, copper-seeded aluminum powder.
144. The electromagnetic interference shielding material
according to claim 140 wherein the noble metal plated
non-noble metal substrate is a silver plated, copper-seeded
aluminum powder.
-111-
145. An electromagnetic interference shielding material
comprising a matrix material selected from the group
consisting of a rubber, a plastic material, an elastic
material and mixtures thereof, which is filled with an amount
of a gold or silver plated nickel powder.
146. The electromagnetic interference shielding material
according to claim 140 wherein the noble metal plated
non-noble metal substrate is a gold plated nickel powder.
147. The electromagnetic interference shielding material
according to claim 141 wherein the copper powder has
spherical shaped particles with a mean diameter of from 5 to
15 microns; the weight of coating is from 15 to 60 weight
percent of the total weight of final coated powder; the
starter plating solution is divided into 5 portions with the
plating solution baths prepared therefrom containing,
respectively, from 75% to 85% of the total noble metal ions
to be plated in the first bath; 10% to 20% of the total
noble metal ions to be plated in the second bath; 1% to
5% of the total noble metal ions to be plated in the third
bath; and 0.1% to 0.5% of the total noble metal ions to be
plated in each of the fourth and fifth baths, such that the
total of all fractions in the 5 baths is 1.0; the first bath
is maintained at a temperature of from about 50 °C to about
80 °C; the second through fifth baths are maintained at a
temperature of from about 85 °C to about 100 °C; the first
series of rinse steps is performed once and comprises the
sequence of steps of rinsing once with warm water followed by
rinsing once with hot water; the second series of rinse steps
is repeated 4 times in succession after completion of the
first series of rinses following plating in the fifth plating
solution bath and comprises the sequence of steps of rinsing
once with hot water; rinsing once with 25% glacial acetic
acid aqueous solution; rinsing a second time with hot water;
and rinsing once with methanol; and the third series of
rinses is performed once and comprises the sequence of steps
of rinsing 3 times with hot water, followed by rinsing 3
times with methanol; and further comprising performing a
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second series of rinse steps once after completion of the
first series of rinse steps which follows after plating in
the third plating solution bath.
148. The electromagnetic interference shielding material
according to claim 147 wherein the weight of coating is 17.6
weight percent of the total weight of final coated powder and
the plating solution baths contain, respectively, 80% of the
total noble metal ions to be plated in the first bath; 16%
of the total noble metal ions to be plated in the 25 second
bath; 3-2% of the total noble metal ions to be plated in the
third bath; and 0-4% of the total noble metal ions to be
plated in each of the fourth and fifth baths.
149. The electromagnetic interference shielding material
according to claim 142 wherein the nickel powder has
spherical shaped particles with a mean diameter of from 5 to
15 microns; the weight of coating is from 15 to 60 weight
percent of the total weight of coated powder; the starter
plating solution is divided into 4 equal portions with the
plating solution baths prepared therefrom each containing
0.25 of the total noble metal ions to be plated; the first
bath is maintained at a temperature of from about 50 °C to
about 80 °C; the second through fourth baths are maintained
at a temperature of from about 85 °C to about 100 °C; the
first series of rinse steps comprises the sequence steps of
rinsing twice with hot water; the second series of rinse
steps is repeated 4 times in succession after completion of
the first series of rinses following plating in the fourth
plating solution bath and comprises the sequence of steps of
rinsing once with hot water; rinsing once with 25% glacial
acetic acid aqueous solution; rinsing a second time with hot
water; and rinsing once with methanol; and the third series
of rinses is performed once and comprises the sequence of
steps of rinsing 3 times with hot water, followed by rinsing
3 times with methanol; and further comprising cleaning and
activating the nickel powder substrate prior to its immersion
in the first plating solution bath.
-113-
150. The electromagnetic interference shielding material
according to claim 149 wherein the weight of coating is 16.0
weight percent of the total weight of final coated powder,
the first bath is maintained at a temperature of about 75 °C;
and the second through fourth baths are maintained at a
temperature of about 100 °C.
151. The electromagnetic interference shielding material
according to claim 144 wherein the aluminum powder seeded
with copper atoms has spherical shaped particles with a mean
diameter of from 5 to 15 microns and seeded with copper
atoms; the weight of coating is from 15 to 60 weight percent
of the total weight of final coated powder; the starter
plating solution is divided into 2 equal portions with the
plating solution baths prepared there- from each containing
50% of the total noble metal ions to be plated; the first
bath is maintained at a temperature of from about 25 °C to
about 35 °C; the second bath is maintained at a temperature
of from about 60 °C to about 70 °C; the first series of rinse
steps is performed once and comprises rinsing twice in
succession with cold water; the second series of rinse steps
is repeated 4 times in succession after completion of the
first series of rinses following plating in the second
plating solution bath and comprises the sequence of steps of
rinsing once with hot water; rinsing once with 25% glacial
acetic acid aqueous solution; rinsing a second time with hot
water; and rinsing once with methanol; and the third series
of rinses is performed once and comprises the sequence of
steps of rinsing 3 times with hot water, followed by rinsing
3 times with methanol; and still further comprising the
initial steps of cleaning and activating the aluminum powder;
seeding the aluminum powder with copper atoms; and mixing the
copper-seeded aluminum powder with liquid detergent before
the first plating step.
152. The electromagnetic interference shielding material
according to claim 151 wherein the weight of coating is 20.3
weight percent of the total weight of final coated powder,
the first bath is maintained at a temperature of about 32 °C;
-114-
and the second bath is maintained at a temperature of about
65 °C
153. The electromagnetic interference shielding material
according to claim 146 wherein the nickel powder has
spherical shaped particles with a mean diameter of from 8 to
10 microns; the weight of coating is from 15 to 60 weight
percent of the total weight of coated powder; the starter
plating solution is divided into 4 equal portions with the
plating solution baths prepared therefrom each containing
25% of the total noble metal ions to be plated; the first
bath is maintained at a temperature of from about 50 °C to
about 80 °C; the second through fourth baths are maintained
at a temperature of from about 85 °C to about 100 °C; the
first series of rinse steps comprises the sequence steps of
rinsing twice with hot water; the second series of rinse
steps is repeated 4 times in succession after completion of
the first series of rinses following plating in the fourth
plating solution bath and comprises the sequence of steps of
rinsing once with hot water; rinsing once with 25% glacial
acetic acid aqueous solution; rinsing a second time with hot
water; and rinsing once with methanol; and the third series
of rinses is performed once and comprises the sequence of
steps of rinsing 3 times with hot water, followed by rinsing
3 times with methanol; the process further comprising
cleaning and activating the nickel powder substrate prior to
its immersion in the first plating solution bath..
154. The electromagnetic interference shielding material
according to claim 153 wherein the weight of coating is 16.0
weight percent of the total weight of final coated powder,
the first bath is maintained at a temperature of about 75 °C;
and the second through fourth baths are maintained at a
temperature of from about 94 °C to about 98 °C.
155. An electrically conductive material comprising a
copolymer matrix containing at least one compound selected
from the group consisting of chlorinated biphenyl,
chlorinated triphenyl, amorphous polypropylene, ethylene,
-115-
vinyl acetate, phenol, formaldehyde, and terpine, together
with a noble metal coated non-noble metal substrate,
wherein the noble metal plated non-noble metal substrate
is produced by the electroless deposition of the noble metal,
selected from the group consisting of silver, gold, platinum,
palladium, irridium, rhodium, ruthenium and osmium, onto the
substrate, selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, thalium and combinations of a principal one of the
foregoing substrate materials seeded with atoms of another
one of the foregoing substrate materials having a greater
affinity than the principal substrate material for the noble
metal being plated thereon,
from a plurality of aqueous solution plating baths
prepared by division into said plurality of baths of a
starter aqueous plating solution containing a total quantity
of free noble metal ions sufficient to plate the non-noble
metal substrate with a selected amount of noble metal coating
of from 2-60 percent of the total weight of final coated
substrate, such that each of said plurality of baths contains
a specified fraction of the total amount of free noble metal
ions to be deposited, and is brought to a specified
concentration by the addition of water thereto;
and further wherein the free noble metal ions are
deposited onto the substrate from a first one of the plating
solution baths maintained at a temperature in the range of
from about 20 °C to about 100 °C, until the plating solution
bath is substantially depleted of free noble metal ions,
thereby forming a first intermediate plated substrate which
is separated from the depleted plating solution bath, rinsed
at least once with a first series of rinse steps selected
from the group consisting of rinsing twice in succession with
cold water; rinsing once with warm water, followed by rinsing
once with hot water; and rinsing twice in succession with hot
water;
the final plated substrate, coated with the total amount
of noble metal ions in the original starter plating solution,
is prepared by repeating the deposition, separation and first
-116-
rinsing sequence steps with the intermediate plated substrate
from the previous sequence of steps to form a next plated
substrate, cumulatively plated with the fractions of noble
metal ions contained in the subsequent plating solution baths
into which the substrate has been immersed, until all of said
plating solution baths have been utilized;
the final plated substrate then being rinsed at least
once with a second series of rinse steps, including rinsing
once with hot water, rinsing once with a weak acid selected
from the group consisting of aqueous solutions of glacial
acetic acid, dilute hydrochloric acid, dilute nitric acid,
and hydrazine; rinsing a second time with hot water, and
rinsing once with an alcohol selected from the group
consisting of lower alkanols having from 1 to 4 carbon atoms;
rinsing at least once with a third series of rinse steps
including rinsing from 1 to 3 times in succession with hot
water, followed by rinsing from 1 to 3 times in succession
with an alcohol selected from the group consisting of lower
alkanols having from 1 to 4 carbon atoms; and
drying to form the final noble metal plated non-noble
metal substrate for use in the electrically conductive
material.
156. An electrically conductive thermosetting plastic
comprising a modified polyamine, xylene solvent,
diisocyanate, and toluene solvent, together with a noble
metal coated non-noble metal substrate
wherein the noble metal plated non-noble metal substrate
is produced by the electroless deposition of the noble metal,
selected from the group consisting of silver, gold, platinum,
palladium, irridium, rhodium, ruthenium and osmium, onto the
substrate, selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, thalium and combinations of a principal one of the
foregoing substrate materials seeded with atoms of another
one of the foregoing substrate materials having a greater
affinity than the principal substrate material for the noble
metal being plated thereon,
-117-
from a plurality of aqueous solution plating baths
prepared by division into said plurality of baths of a 25
starter aqueous plating solution containing a total quantity
of free noble metal ions sufficient to plate the non-noble
metal substrate with a selected amount of noble metal coating
of from 2-60 percent of the total weight of final coated
substrate,
and further wherein the free noble metal ions are
deposited onto the substrate from a first one of the plating
solution baths maintained at a temperature in the range of
from about 20 °C to about 100 °C, until the plating solution
bath is substantially depleted of free noble metal ions,
thereby forming a first intermediate plated substrate which
is separated from the depleted plating solution bath, rinsed
at least once with a first series of rinse steps selected
from the group consisting of rinsing twice in succession with
cold water; rinsing once with warm water, followed by rinsing
once with hot water; and rinsing twice in succession with hot
water;
the final plated substrate, coated with the total amount
of noble metal ions in the original starter plating solution,
is prepared by repeating the deposition, separation and first
rinsing sequence steps with the intermediate plated substrate
from the previous sequence of steps to form a next plated
substrate, cumulatively plated with the fractions of noble
metal ions contained in the subsequent plating solution baths
into which the substrate has been immersed, until all of said
plating solution baths have been utilized;
the final plated substrate then being rinsed at least
once with a second series of rinse steps, including rinsing
once with hot water, rinsing once with a weak acid selected
from the group consisting of aqueous solutions of glacial
acetic acid, dilute hydrochloric acid, dilute nitric acid,
and hydrazine; rinsing a second time with hot water, and
rinsing once with an alcohol selected from the group
consisting of lower alkanols having from 1 to 4 carbon atoms;
rinsing at least once with a third series of rinse steps
including rinsing from 1 to 3 times in succession with hot 10
water, followed by rinsing from 1 to 3 times in succession
- 118-
with an alcohol selected from the group consisting of lower
alkanols having from 1 to 4 carbon atoms; and
drying to form the final noble metal plated non-noble
metal substrate for use in the electrically conductive
thermosetting plastic.
157. An electrically conductive adhesive material
comprising chlorinated biphenyl, chlorinated triphenyl, and
amorphous polypropylene, together with a noble metal coated
non-noble metal substrate
wherein the noble metal plated non-noble metal substrate
is produced by the electroless deposition of the noble metal,
selected from the group consisting of silver, gold, platinum,
palladium, irridium, rhodium, ruthenium and osmium, onto the
substrate, selected from the group consisting of copper,
nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, thalium and combinations of a principal one of the
foregoing substrate materials seeded with atoms of another
one of the foregoing substrate materials having a greater
affinity than the principal substrate material for the noble
metal being plated thereon,
from a plurality of aqueous solution plating baths
prepared by division into said plurality of baths of a
starter aqueous plating solution containing a total quantity
of free noble metal ions sufficient to plate the non-noble
metal substrate with a selected amount of noble metal coating
of from 2-60 percent of the total weight of final coated
substrate, such that each of said plurality of baths contains
a specified fraction of the total amount of free noble metal
ions to be deposited, and is brought to a specified
concentration by the addition of water thereto;
and further wherein the free noble metal ions are
deposited onto the substrate from a first one of the plating
solution baths maintained at a temperature in the range of
from about 20 °C to about 100 °C, until the plating solution
bath is substantially depleted of free noble metal ions,
thereby forming a first intermediate plated substrate which
is separated from the depleted plating solution bath, rinsed
-119-
at least once with a first series of rinse steps selected
from the group consisting of rinsing twice in succession with
cold water; rinsing once with warm water, followed by rinsing
once with hot water; and rinsing twice in succession with hot
water;
the final plated substrate, coated with the total amount
of noble metal ions in the original starter plating solution,
is prepared by repeating the deposition, separation and first
rinsing sequence steps with the intermediate plated substrate
from the previous sequence of steps to form a next plated
substrate, cumulatively plated with the fractions of noble
metal ions contained in the subsequent plating solution baths
into which the substrate has been immersed, until all of said
plating solution baths have been utilized;
the final plated substrate then being rinsed at least
once with a second series of rinse steps, including rinsing
once with hot water, rinsing once with a weak acid selected
from the group consisting of aqueous solutions of glacial
acetic acid, dilute hydrochloric acid, dilute nitric acid,
and hydrazine; rinsing a second time with hot water, and
rinsing once with an alcohol selected from the group
consisting of lower alkanols having from 1 to 4 carbon atoms;
rinsing at least once with a third series of rinse steps
including rinsing from 1 to 3 times in succession with hot
water, followed by rinsing from 1 to 3 times in succession
with an alcohol selected from the group consisting of lower
alkanols having from 1 to 4 carbon atoms; and
drying to form the final noble metal plated non-noble
metal substrate for use in the electrically conductive
adhesive material.
158. An electrically conductive material comprising a
polyamide resin and an epoxy, together with a noble metal
coated non-noble metal substrate
wherein the noble metal plated non-noble metal substrate
is produced by the electroless deposition of the noble metal,
selected from the group consisting of silver, gold, platinum,
palladium, irridium, rhodium, ruthenium and osmium, onto the
substrate, selected from the group consisting of copper,
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nickel, aluminum, titanium, zirconium, vanadium, hafnium,
cadmium, niobium, tantalum, molybdenum, tungsten, gallium,
indium, thalium and combinations of a principal one of the
foregoing substrate materials seeded with atoms of another
one of the foregoing substrate materials having a greater
affinity than the principal substrate material for the noble
metal being plated thereon,
from a plurality of aqueous solution plating baths
prepared by division into said plurality of baths of a
starter aqueous plating solution containing a total quantity
of free noble metal ions sufficient to plate the non-noble
metal substrate with a selected amount of noble metal coating
of from 2-60 percent of the total weight of final coated
substrate, such that each of said plurality of baths contains
a specified fraction of the total amount of free noble metal
ions to be deposited, and is brought to a specified
concentration by the addition of water thereto;
and further wherein the free noble metal ions are
deposited onto the substrate from a first one of the plating
solution baths maintained at a temperature in the range of
from about 20 °C to about 100 °C, until the plating solution
bath is substantially depleted of free noble metal ions,
thereby forming a first intermediate plated substrate which
is separated from the depleted plating solution bath, rinsed
at least once with a first series of rinse steps selected
from the group consisting of rinsing twice in succession with
cold water; rinsing once with warm water, followed by rinsing
once with hot water; and rinsing twice in succession with hot
water;
the final plated substrate, coated with the total amount
of noble metal ions in the original starter plating solution,
is prepared by repeating the deposition, separation and first
rinsing sequence steps with the intermediate plated substrate
from the previous sequence of steps to form a next plated
substrate, cumulatively plated with the fractions of noble
metal ions contained in the subsequent plating solution baths
into which the substrate has been immersed, until all of said
plating solution baths have been utilized;
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the final plated substrate then being rinsed at least
once with a second series of rinse steps, including rinsing
once with hot water, rinsing once with a weak acid selected
from the group consisting of aqueous solutions of glacial 25
acetic acid, dilute hydrochloric acid, dilute nitric acid,
and hydrazine; rinsing a second time with hot water, and
rinsing once with an alcohol selected from the group
consisting of lower alkanols having from 1 to 4 carbon atoms;
rinsing at least once with a third series of rinse steps
including rinsing from 1 to 3 times in succession with hot
water, followed by rinsing from 1 to 3 times in succession
with an alcohol selected from the group consisting of lower
alkanols having from 1 to 4 carbon atoms; and
drying to form the final noble metal plated non-noble
metal substrate for use in the electrically conductive lo
material.
159. The electromagnetic interference shielding material
according to claim 142 wherein the matrix is from about 5 to
about 20 weight percent of the overall material, and the
noble metal coated non-noble metal powder is from about 95 to
about 80 weight percent of the overall material.
