Note: Descriptions are shown in the official language in which they were submitted.
.
3 3.
The present invention is concerned with a
waterborne coating composition designed for the coating
of transportation vehicles. The invention is related to
coating compositions primarily for a base coat of a
multi-coat system which includes primers and transparent
clear coats, particularly with base coats containing
metallic pigments, based on acrylic latex polymers.
It is customary in the painting of an
automobile that a series of coatings, be applied to the
substrate. The first coat being the primer followed by
the base coat and ~inally the clear coat. The base coat
provides the good decorative quality to the final finish
via organic and inorganic pigments. In many automobile
finishes, a metallic finish is desired. To obtain this
metallic effect, metallic pigments are present in the
base coat typically aluminum flakes.
In the current market place, automobile
coatings, especially base coats, contain a high level of
organic solvent. With increasing concern about the
volatile organic emissions into the atmosphere, an
intensive effort in research and development in coatings
containing mainly water as the solvent with a small
level of organic solvent is under way. An example of
such an effort is US patent No. 4 730 020 which
discloses a water-dilutable coating composition
comprising specifically selected acrylic copolymers,
solvent blends, coloring and/or optical effect pigments
and polymer dispersions. To obtain the desired optical
effect of the metallic flakes, the correct combination
of acrylic copolymer and solvent blend must be achieved.
An aqueous thermosetting acrylic resin described by US
patent 3 862 071 controls the metallic pigment
orientation by the addition of a water insoluble
copolymer. Microgel technology as described by GB-PS No.
2 073 609 also results in the proper metal orientation.
Also disclosed in DE No. 3 210 051 is an attempt to
: :: :: :
control metallic pigment orientation using polyurethane
dispersions. Cellulosic esters have also been used to
control metal fixation as disclosed in DE No. 3 216 549.
In general, the metal fixation in base coats
is achieved by a rheology modifiers such as inorganic
and organic thickeners. All previous rheology modifiers
or rheology control agents for water borne coatings have
poor shelve stability, poor weathering characteristics
and are cumbersome to use. The particular rheology
control agent used in this invention results in a non-
mottled, high head-on-brightness, outstanding flop, and
high quality finish, even in the case of a silver
metallic base coat and does not suffer from the problems
cited earlier.
Typically, coating compositions used in the
automotive market, especially in the automotive after
market, are produced by mixing various bases to give the
desired color. These coating compositions are then
applied in about 1-5 days after preparation. A major
problem is the introduction of aluminum flakes which
react with water to generate hydrogen gas. Therefore,
the aluminum flake must be segregated from the rest of
the waterborne components to minimize this hazard. This
invention also describes a method for the storage of
aluminum flake in an organic medium with introduction of
the flakes into the aqueous ervironment just prior to
application of the coating system.
This invention relates to waterborne
compositions for use in metallic and nonmet~llic base
coats in a multicoat system for the automotive market.
More specially, the present invention is concerned with
an acrylic latex coating composition for use in an
automotive paint base coat composition. The invention
also relates to base coats containing pigments, me-tallic
pigments, organic solvents, and conventional paint
additives. The outstanding metal control exhibited by
this coating composition is attrib~ted to the rheology
control agent and the film shrinkage of the latex
vehicle while drying. The use of acrylic latex results
in a very fast dry time. This coating composition
provides a base coat that satisfies current and proposed
volatile organic compound regulations. Even with
conventional non~metallic pigments, the coating exhibits
excellent appearance.
This invention describes a method for the
storage of aluminum flake in an organic medium with
introduction of the flakes into the aqueous environment
just prior to application of the coating system. This
method minimizes the potential hazard of the aluminum
flake reacting with water to form hydrogen gas during
storage. This method can also be used for the storage of
other water sensitive pigments such as copper and brass.
Other pigments such as plastic films, mica and coated
metallic foils can be stored using this method.
The automotive base coat pain~ comprises
five components; A) aluminum base, B) neutralization
base, C) clear resin base, D) pigmented base, and E)
surfactant base~ Component A, the aluminum base, is
composed of metallic flakes slurred into a solvent borne
resin and water miscible solvents. The resin used in
this component may be a water reducible acrylic, water
reducible polyester, or water reducible alkyd. Commonly
used metallic pigments, used singularly or as a mixture
are copper, copper alloys, aluminum, steel, mica,
plastic films, and coated metallic foils, preferably
aluminum at a lavel of 10-30 % by weight, preferably 20-
30 ~ by weight. The aluminum hase contains 5-40~,
preferably 20-30~ by weight of the solvent borne water
reducible resin. The organic solvent for this base must
be water miscible. Examplss of solvents are methanol,
ethanol, propanol, butanol, N-methylpyrrolidone,
glycols, glycol esters, glycol acetates, diethylene
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glycol ethers, diethylene glycol acetates, propylene
glycol esters, propylene glycol acetates, dipropylene
glycol, dipropylene glycol acetates, specially preferred
are ethylena glycol propyl ether, ethylene glycol butyl
ether, ethylene glycol hexyl ether, propylene methyl
ether, propylene ethyl ether, propylene propyl ether,
propylene butyl ether, propylene hexyl ether,
dipropylene methyl ether, dipropylene ethyl ether,
dipropylene propyl ether, and dipropylene butyl ether.
Component B, neutralization base, is
composed of a solvent borne water reducible resin,
neutralized with an amine, preferably ammonia dispersed
in water to a level of 10-25 %, preferably 10-20 ~ by
weight. Excess amine, preferably ammonia, is added at a
level of 1-10 ~, preferably 5-10 %, by weight.
Component C, clear resin base, contains; 1)
acrylic latex polymer at a level of 10-50 ~, preferably
25-35 %, 2) 0-15 ~ water miscible solvent, preferably 5-
12 %, 3) 0.5-5.0 % hydrophilic silica, prefe.rably 1.5-
2.5 %. The hydrophilic silica can be dispersed into the
acrylic late~ polymer by normal dispersing techniques.
Component D, pigment base, contains acrylic
latex grinding polymer at a level of 5-50 ~, preferably
15-30 ~. This level depends on the pigment in the
component. The level of pigment in component D is 0.5-35
% by weight, this level depends on the pigment
characteristics also. Typically, a pigment to binder
weight ratio of about 10/100 to 300/100 is acceptable.
The pigments are typically ground using conventional
dispersion equipment such as sand mills, pearl mills,
ball mills, horizontal mills, and vertical mills.
Optional wetting agents, surfactants, and dispersing
aids can be employed.
Component E, surfactant base, contains a
polymer fluorocarbon surfactant at a level of 0.1-4.0 ~,
preferably 2.0-3.0 % in water.
2~3~3 ~
This invention is directed to a coating
composition for a water borne base coat especially
designed for the automotive market. This invention
describes a method for the introduction of m~tallic
flakes into a waterborne coating resulting in a highly
superior base coat. The proper metal fixation is
accomplished by the use of a novel rheology control
agent which employs hydrophilic silica and a polymeric
nonionic fluorocarbon surfactant. The novel rheology
10 control agent described and claimed in copending related
US application and filed and
incorporated herein by re~erence. The basecoat is broken
down into five bases that are combined just prior to
application of the base coat.
The invention describes a method for the
storage of aluminum flake in an organic medium with
introduction of the flakes into the aqueous environment
just prior to application of the coating system. This
method minimizes the potential hazard of the aluminum
20 flake reacting with water to form hydrogen gas during
storage.
Component A, aluminum base, is an aluminum
slurry in an organic environnient containing either a low
to moderate acid number acrylic or polyester or alkyd.
25 The acid number of these polymers based on solids should
be about 15 to 65. The preferred polymer is a water
reducible solvent borne acrylic modified with glycidyl
esters. The acrylic polymer is prepared via normal
solution polymerization techniques. The acrylic polymer
30 is composed of; 1) 3-5 ~ by weight of an ethylenically
unsaturated carboxylic acid such as methacrylic acid and
acrylic acid, preferably methacrylic acid, 23 15-30 % by
weight methylmethacylate, 3) 5-20 ~ by weight 2-
ethylhydroxymethacrylate, 4) 1-10 % by weight isobornyl
methacrylate, and 5) optionally 5 20 % by weight of a
glycidyl ester of a tertiary C10 fatty acid. The acrylic
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polymer is prepared in organic solvents that are water
miscible, such as methyl ethyl ketone, acetone, ethanol,
methanol, propanol, butanol, N-methylpyrrolidone,
glycols, glycol ethers, glycol acetates, diethylene
glycol ethers, diethylene glycol acetates, propylene
glycol ethers, propylene glycol acetates, dipropylene
glycol ethers, dipropylene glycol acetates, specially
preferred are ethylene glycol propyl ether, ethylene
glycol butyl ether, ethylene glycol hexyl ether,
propylene methyl ether, propylene ethyl ether, propylene
propyl ether, propylene butyl ether, propylene hexyl
ether, dipropylene methyl ether, dipropylene ethyl
ether, dipropylene propyl ether, methyl ethyl ketone and
dipropylene butyl ether. Optionally, surfactants can
also be present during the polymerization at a level of
0.1-2O0 ~ by weight. The viscosity of the final polymer
is 16000 to 18000 cps with a solids content of 50-75 ~
by weight, preferably 55-65 ~ by weight. The acid number
of the polymer based on solids should be 10-70,
preferably 15-65.
Any commercial aluminum paste available for
solvent borne or waterborne applications can be used in
the preparation of component A. The amount of aluminum
flake in the component is 4-30 ~ by welght, preferably
23-30 ~ by weight.
Other nonmetallic and metallic pigments that
can be incorporated lnto this base include copper,
copper alloys, mica, coated metallic foils, plastic
flakes and steel. However, this is not a conclusive
list.
Additional organic solvent may be needed to
reduce the viscosity of the acrylic resin. Acceptable
solvents must be water miscible such as methyl ethyl
ketone, acetone, ethanol, methanol, propanol, butanol,
N-methylpyrrolidone, glycols, glycol ethers, glycol
acetates, diethylene glycol ethers, diethylene glycol
2 ~ ~3~J`~ l
acetates, propylene glycol ethers, propylene glycol
acetates, dipropylene glycol ethers, dipropylene glycol
acetates, specially preferred are ethylene glycol propyl
ether, ethylene glycol butyl ether, e~hylene glycol
hexyl ether, propylene methyl ether, propylene ethyl
ether, propylene propyl ether, propylene butyl ether,
propylene hexyl ether, dipropylene methyl ether,
dipropylene ethyl ether, dipropylene propyl ether, and
dipropylene butyl ether. Component A has a to~al solids
of 25 ~ to 50 ~ by weight, 5 % to 35 % binder by weight,
and 35 ~ to 50 ~ organic solvent by weight. Additional
wetting, anti-settling additives common to the paint
industry may be added.
The preparation of component A, the aluminum
base, is critical for the proper appearance of the
aluminum flake in the final coating. The proper amount
of the acrylic resin solution is dissolved into the
proper amount of water miscible organic solvent, such as
methyl ethyl ketone, acetone, ethanol, methanol,
propanol, butanol, N-methylpyrrolidone, glycols, glycol
ethers, glycol acetates, diethylene glycol ethers,
diethylene glycol acetates, propylene glycol ethers,
propylene glycol acetates, dipropylene glycol ethers,
dipropylene glycol acetates, specially preferred are
ethylene glycol propyl ether, ethylene glycol butyl
ether, ethylene glycol hexyl ether, propylene methyl
ether, propylene ethyl ether, propylene propyl ethex,
propylene butyl ether, propylene hexyl ether,
dipropylene methyl ether, dipropylene ethyl ether,
dipropylene propyl ether, and dipropylene butyl ether.
The proper amount of the aluminum paste is slurred into
the above described resin solutionO The aluminum slurry
must be stirred until the bas~ is smooth and uniform.
Component B, neutralization base, is an
aqueous solution containing dispersed acrylic resin and
ammonia. The acrylic described above is used in the
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component. Other water reducible resins such as
polyester and alkyds may be used. An aqueous solution
containing O.l-15.0 ~, preferably 0.1-8.0 ~ ammonia by
weight is prepared. The correct amount of the acrylic
resin, usually 5-25 ~ by weight, preferably 10-20 % by
weight, is added to the basic aqueous solution and
stirred~ The resulting solution should be clear to
slightly turbid and have a pH range of 7.5 10.0,
preferably 8.0 to 10Ø The r4sulting solution should
have a nonvolatile range of 5-25 ~ by weight,preferably
10-20 ~.
Component C, clear resin base, of the
coatlng composition contains an acrylic latex. Typical
properties of this acrylic latex are as follows:
Solids content, % 20-60
pH 7 -to 10
Weight per gallon, lbs 8.0 to 9.0
Minimum film formation temperature, C O to 70
Sward hardness 25 to 110
Mechanical stability OK
Glass transitition temperature, C 10 to 50
Average molecular weight 150,000 to 300,000
Number average molecular weight 30,000 to 60,000
Acid number on solids 5 to 35
Volatile organic solvents, ~ O to 20
Particle size, nm 50 to 150
Specially preferred acrylic latics are
Neocryl A-622, Neocryl A-640, Neocryl A-6037 sold by ICI
resins, Joncryl J-537, Joncryl J-538 sold by Johnson
Wax, Arolon 860-W-45 sold by NL Industries. The amount
of this acrylic latex in this component is 15 45 % by
weight, preferably 25-35 ~ by weight. The level of
organic solvent in this component is 5.0-30 % by weight,
preferably 5-15 ~ by weight, and the solvent must be
water miscible. Examples of water miscible solvents are
methyl ethyl ketone, acetone, ethanol, methanol,
2 ~
propanol, butanol, N-methylpyrrolidone, gly~ols, glycol
ethers, glycol acetates, diethylene glycol ethers,
diethylene glycol acetates, propylene glycol ethers,
propylene glycol acetates, dipropylene glycol ethers,
diprcpylene glycol acetates, specially preferred are
ethylene glycol propyl ether, ethylene glycol butyl
ether,~ ethylene glycol hexyl ether, propylene methyl
ether, propylene ethyl ether, propylene propyl ether,
propylene butyl ether, propylene hexyl ether,
dipropylene methyl ether, dipropylene ethyl ether,
dipropylene propyl ether, and dipropylene butyl ether.
This component may also contain other conventional paint
additives such as thickening agents, extenders,
plasticizers, stabilizers,light stabilizers, wetting
agents, waxes, antifoams, defoamers and catalysts,
singly or a multitude of them at the conventional
levels.
Hydrophilic colloidal silica is also present
in this component at a level o~ 1.0-8.0 % by weight,
preferably 2.0-3.0 % by weight. The particle size of the
hydrophilic colloidal silica is about 1.0 10,000
millimicron and a surface area of about 50-1200 square
meters per gram. The silica is about 99.8 ~ silicon
dioxide by weight and exist in three dimensional
branched chain aggregates and has a surface that is
hydrophilic and capable of hydrogen bonding. The silica
is dispersed into the above resin solution using
conventional techniques, such as ball mills, pebble
mills, horizontal mills vertical mills and ~earl mills.
The total nonvolatile range o~ this component is 20-50
%, preferably 25-35 ~ by weight.
Component D, pigmented base, imparts the
coloring effect upon the coating composition. The resin
used for the dispersing of the pigments is an acrylic
latex. Typical properties of this acrylic latex are as
follows:
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Solids content, ~ 20-60
pH 7 to 10
Weight per gallon, lbs 8.0 to 9.0
Minimum film formation tamperature, C 0 to 70
Sward hardness 25 to 110
Mechanical stability OK
Glass transitition temperature, C 10 to 50
Average molecular weight 150,000 to 300,000
Number average molecular weight 30,000 to 60,000
Acid number on solids 5 to 35
Volatile or~anic solvents, ~ 0 to 20
Particle size, nm 50 to 150
Specially preferrad acrylic latics are
Neocryl A-622, Neocryl A-640, Neocryl A-6037 sold by ICI
resins, Joncryl J-537, Joncryl J-538 sold by Johnson
Wax, Arolon 860-W-45 sold by NL Industries. The level of
this resin in component D is 15-60 ~ by weight,
preferably 20 40 % by weigh-t. The organic, inorganic
pigments and/or dyestuffs are ground with this resin
employin~ standard techniques. Examples of dispersing
equipment are ball mills, pebble mills, pearl mills,
horizontal mills, and vertical mills. Examples of
pigments and dyestuffs but not limited to are -titanium
dioxide, graphite, carbon black, zinc oxide, cadminum
sulfide, chromium oxide, zinc sulfide, zinc chromate,
strontium chromate, barium chromate, lead chromate lead
cyanamide, lead silico chromate, chromium oxide, zinc
sulfide, yellow nickel titanium, yellow chromium
titanium, red iron oxide, transparent red oxide,
3Q transparent yellow oxide, black iron oxide, ultramarine
blue, phthalocyanine complexes, amaranth, quinacridones,
and halogenated thioindigo pigments. The level of
pigment/dyestuff in Component D is 0.1 to 35.0 % by
weight, typically 5-25 %. This component may also
contain other conventional paint additives such as
dispersing aids, anti-settling aids, we~ting aids,
~(~3~J`~
11
thickening agents, extenders, plasticizers, stabilizers,
light stabilizers, waxes, antifoams, defoamers and
catalysts singly or a multitude of them at the
conventional levels. Also present in this component is a
water miscible solvent such as methyl ethyl ketone,
acetone, ethanol, methanol, propanol, butanol, N-
methylpyrrolidone, glycols, glycol ethers, glycol
acetates, diethylene glycol ethers, diethylene glycol
acetates, propylene glycol ethers, propylene glycol
acetates, dipropylene glycol ethers, dipropylene glycol
acetates, specially preferred are ethylene glycol propyl
ether, ethylene glycol butyl ether, ethylene glycol
hexyl ether, propylene methyl ether, propylene ethyl
ether, propylene propyl ether, propylene butyl ether,
propylene hexyl ether, dipropylene methyl ether,
dipropylene ethyl ether, dipropylene propyl ether, and
dipropylene butyl ether at a level of 0 to 25 ~ by
weight, preferably 0-12 % by weight.
Component E, surfactant base, contains a
polymeric nonionic fluorocarbon surfactant at a level of
0.1 to 5 % by weight, preferably 2.0 to 3.0 ~ by weight,
in water. The polymeric nonionic fluorocarbon surfactant
contains ethylene oxide linkages, has a weight average
molecular weight of about 5,000 to 50,000 and contains
2-25 ~ of fluorine by weight of the surfactant. One
preferred nonionic fluorocarbon polymer contains about
30-70 ~ by weight ethylene oxide linkages, 10-20 % by
weight of fluorine and has a weight average molecular
weight of about 10,~00-30,000.
The final coating composition is produced by
mixing Components A through E together in order and at
appropriate levels to give the desired color and
metallic effect. Typically, the solids of the final
coating is 5 to 30 % by weight, organic levels 5 to L5 %
by weight. The rheology of the coating is defined by the
amount of colloidal silica and polymeric nonionic
,
12
fluorocarbon surfactant present in the coating. The
level of colloidal silica is 0.5 to 5.0 ~ and 0.05 to
1.0 % of polymeric nonionic fluorocarbon surfactant by
weight of water used in the final base coat formulation.
The water content ranges between 30 to 90 ~ by weight of
the final base coat composition.
Other water reducible resin may be added to
the coating to improve certain film properties such as
aqueous one component aliphatic polyurethane
dispersions, polyesters, and alkyds.
Additional anionic and nonionic surfactants
can be added to the paint composition to increase
wetting of the substrate by the coating such as FC-120,
FC-430 sold by 3M, Surfonyl 104, Surfonyl 440 sold by
Air Products, Triton X100 sold by Rohm and Haas, Troysol
LAC sold by Troy Chemical Company, Aerosol OT's sold by
American Cyanamid including the salts of dialkyl
sulfosuccinates and Igepal's sold by GAF including the
ethoxylated alkyl phenols.
The viscosity of the final base coat is
about 10 Pas at a shear rate of 0.001 1/s and 0.05 at a
shear rate of 1,000 1/s. This base coat exhibits a very
high viscosity at low shear rate while having a low
viscosity at high shear rates. This phenomenon results
in the outstanding metal effect this coating composition
possesses. The efflux time of the coating through a ~4
Ford cup is 15 to 30 seconds at 23 C.
The coating composition can be applied using
conventional spray equipment or high volume low pressure
spray equipment resulting in a high quality finishO
After a flash off time of 15 to 45 minutes, a
transparent top coat can be applied over this basecoat.
Example of transparent top coats are two component,
based on acrylic and/or polyester resins cured with
polyisocyanates, silanes, and acid cured epo~y coatings,
however, this is not an inclusive list. The preferred
,
2 ~
13
transparent top coat is a two component acrylic
polyisocyanate coating.
The following examples illustrate the
invention without limiting the scope thereof.
Example 1; Base Coat Preparation
Preparation of an Acrylic Polymer modified
with A Glycidyl Ester of Tertiary C10
Fatty Acid.
A five liter three neck round bottomed flask
was fitted with an agitator, thermometer, condenser,
nitrogen inlet and monomer inlet ~nd charged with 680 g
of methoxypropanol, 20 g of methyl ethyl ketone. The
mixture was brought to reflux and the temperature
adjusted to 140-141 C by adding 5.0 ~ of methyl ethyl
ketone. A monomer solution was prepared containing 333 g
of propenoic acid, 847 g of methyl-2-methyl-2-
propionate, 450 g of 2~ethylhexyl~2-methylpropionate,
180 g of isobornyl-2-methyl-2-propionate and 27 g of
Surfynol 440. An initiator solution was also prepared
containing 36 g of t-butyl peroxybenzoate and 76 g of
methoxypropanol. The above monomer solution and
initiator solutions were added to the reaction flask at
a uniform rate over two hours. After completion of the
additions, the monomer line was flushed with 35.0 g of
methoxypropanol and a solution containing 15 g of t-
butylperoxybenzoate and 40 g of methoxypropanol was then
added over 10 minutes. The reaction was then refluxed
for an additional 135 minutes. After refluxing, 475 ~ of
a glycidyl ester of a tertiary C10 fatty acid was added
to the flask, heated to reflux and reacted to constant
acid value. The reaction was allowed to cool, then 43 g
of methoxypropanol and 588 g of ethanol were added to
the resin to reduce the viscosity. The properties of the
resin are: viscosity Z5-Z6, solids 60-61 %, and acid
number of 53 to 56 based on solids.
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Preparation of Component A - Aluminum Base
The acrylic resin described above, 44.0 g,
was added to 19.0 g o butoxyethanol. This mixture was
stirred until a homogeneous solution was produced. A
commercial solvent borne aluminum paste, 38.0 g was
added to the resin solution. The resulting slurry was
then stirred until a smooth, uniform slurry was
produced. This aluminum base contains 49.8 % by weight
of volatile organic solvents, 38.4 % by weight of
solids, and 24.3 ~ by weight of aluminum flake.
Preparation of Component B - Neutralization
Base
To 300 g of deionized water, 8.0 g of 30
aqueous ammonia was added. the solution was stirred well
before adding 100.0 g of the acrylic resin described
above. The resulting mixture was stirred until the
solution was clear to slightly turbid. The nonvolatile
level of this base was 14.8 % by weight, water level
74.9 ~ by weight, volatile organic solvent 9.8 % by
weight. The final pH of this dispersion was 9.2.
Preparation of Component C - Clear Resin
Latex
Premixed were 48.0 g of hydrophilic
colloidal silica, 10.0 g of a defoamer and 1865 g of
Neocryl A-622. This mixture was then ground on a
horizontal mill until a particle size of less than 8
microns was achieved. Deionized water, 260 g, was then
added to the above slurry under agitation to yield a
uniform latex solution. The level of silica was 2.2 ~ by
weight. Volatile organic level was 8.9 % by weight and
solids level was 28.3 % by weight.
Preparation of Component D - Pigmented Bases
The ollowing pigment slurry was prepared,
80 g Neocryl A-6037, 2.1 g of 30 ~ aqueous ammonia, 23.9
g of transparent red oxide, and 0.2 g of a defoamer. The
above components were mixed together and predispersed
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using a Cowles blade. The mixture was then ground on a
horizontal mill until the desired particle size was
achieved. A let down solution containing 70.0 g of
Neocryl A-6037 and 2.0 g of 30 % aqueous ammonia was
added to the grind portion. The resulting pigment paste
was reduced under agita~ion with a solution containing
5.75 g of deioni~ed water, 19.2 g o* butoxyethanol. The
resulting pigmented base had a pH of 9.2, a solids level
of 48 % by weight, a volatile organic level of 9.4 % by
weight, a binder level of 36.2 ~ by weight, a pigment
level of 11.8 ~ by weight and a water level of 42.0 % by
weight.
Preparation of Component E - Surfactant Base
To 48 g of deionized water, 2.0 g of a
polymeric nonionic fluorocarbon surfactant was added.
The mixture was stirred to give a slightly turbid
solution.
Example 2 - Preparation of a Waterborne Red
Metallic Base Coat
Component Parts by Weight
Component B 4.0
Neutralization Base
Component A 2.0
Aluminum Base
Component C 72.0
Clear Resin Base
Component D 13.0
Pigmented Base
Component E 9.0
Surfactant 8ase
The above formula was used to prepare a red
metallic base coat. The order of addition is that
listed. After each introduction of a component, the
entire solution was stirred. The base coat was sprayed
on panels primed with an epoxy primer. The base coat was
sprayed on the substrate using conventional spray
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16
equipment until hiding was achieved. The basecoat was
allowed to flash for 30 minutes and ~h~n clear coated
with a transparent coating based on isocyanate
technology. The final properties of the base coat after
coating with a conventional polyurethane clear coat are
listed below, including appearance ratings.
Properties of the Red Metallic Base Coat and
Base Coat/Clear Coat System
Property Value
Water 68.9 %
Volatile Organic 9.1 %
Pigment 2.1 ~
Nonvolatile 28.1 %
Binder 24.0 %
Weight per Gallon (lbs/gal)8.3
VOC tlbs/gal) 2.2
Gloss, 20 deg 82
DOI 85
Adhesion good
Film Thickness (mil) 1.0
Humidity good
Water Spray excell.
Metal Control excell.
Example 3 - Preparation of a Waterborne
SilveI Metallic
Component B 18.0
Neutralization Base
Component A 9.1
Aluminum Base
Component C 63.6
Clear Base
Component D 9.1
Surfactant Base
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The above formula was used to prepare a
silver metallic base coat. The order of addition is that
listed. After each introduction of a component, the
entire solution was stirred. The base coat was sprayed
on panels primed with an epoxy primer. The base coat was
sprayed on the substrate using conventional spray
equipment until hiding was achieved. The base coat was
allowed to flash for 30 minutes and then clear coated
with a transparent coating based on isocyanate
technology. The final properties of the base coat after
coating with a conventional polyurethane clear coat are
listed below, including appearance ratings.
Properties of the Silver Metallic Base Coat
and Base Coa~/Clear Coat system
Property Value
Water 67.9 %
Volatile Organic 12.2 %
Pigment 2.5 %
Nonvolatile 24.4 %
Binder 22.8 %
Weight per Gallon (lbs/gal) 8.3
VOC (lbs/gal) 3.0
Gloss, 20 83
DOI 82
Adhesion good
Film Thickness (mil) 0.8
Humidity good
Water Spray excell.
Metal Control excell.
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