Note: Descriptions are shown in the official language in which they were submitted.
CA 02351162 2001-06-21
990234 RS/AL
1
Priated media coatiag
The invention relates to printed media coating, a process
for its preparation and its use.
A media coating as a rule comprises a coating arranged on a
medium. The coating is used as an ink uptake layer.
It is known from EP 0514633 that the ink uptake layer,
which is arranged on a carrier, comprises a polyvinyl
alcohol, a cationic polymer which contains no crosslinking
groups, an amorphous silica with a specific surface area of
200 to 400m2/g and a particle size of 2 to 12 ~,m and
poly(methyl vinyl ether)-malefic acid anhydride and/or a
benzotriazole derivative.
EP 0759635 discloses an ink jet recording material which
has a carrier and at least one recording layer on the
carrier, at least one of the recording layers comprising
colloidal particles and a water-soluble resin.
The known inks and coating materials have the disadvantage
that they have a low water resistance.
The object of the present invention is to provide a printed
media coating of improved print quality, water resistance
and high printing speed.
The invention provides a printed media coating, wherein at
least one constituent of the ink is bonded to at least one
constituent of the media coating via a chemical bond.
The media can be used as carriers for the media coating.
The media for the media coating can be glass, ceramic,
plastic, textiles, leather or paper. The printed media
coating can be bonded to the media via one or more
intermediate layers.
CA 02351162 2001-06-21
990234 RS/AL
2
The invention also provides an ink, wherein at least one
constituent of the ink forms a chemical bond with at least
one constituent of the media coating.
The invention also provides a media coating, wherein at
least one constituent of the media coating forms a chemical
bond with at least one constituent of the ink.
The invention also provides a process for the production of
the printed media coating, which comprises spraying,
printing or atomizing the ink on to the media coating and
reacting at least one constituent of the ink with at least
one constituent of the media coating to form a chemical
bond.
The chemical bonding of the ink to the media coating can
take place according to the following reactions:
(a) The ink can comprise nitrite, preferably zinc, sodium,
potassium or lithium nitrite, and carbon black and/or
dyestuff and the media coating can comprise a compound
containing amino groups.
Furnace, gas, flame, acetylene blacks or inversion
blacks, known from DE 195 21 565, can be used as the
carbon black. The dyestuffs can be compounds with
aromatic systems.
Precipitated or pyrogenic silicas, pyrogenic oxides,
chalk, kaolins, mica, zinc oxide, which are modified by
a chemical reaction, for example with silanes, such that
these contain primary amino groups, preferably aryl-
bonded primary amino groups, on the surface, can be used
as the compounds containing amino groups.
The reaction can take place in the acid pH range. For
this, the media coating is formulated such that after
printing of the media coating, a pH of < 6.0, preferably
< 3.0, is present.
After the printing, the nitrite of the ink reacts with
the primary amine of the media coating to form a
990234 RS/AL
CA 02351162 2001-06-21
3
diazonium salt, which then reacts with the carbon black
surface or the dyestuff.
The reaction can proceed according to the following
equation
Media coating
N02- + H=N
+ H~
bla~bon/ \ + ~N ~ ~ _ p
+ Nz
(b)The ink can comprise a doped carbon black or dyestuff
and the media coating can comprise a compound
containing hydroxyl groups, the doped carbon black or
dyestuff and/or the compound containing hydroxyl groups
being modified with a silane. The functional groups of
the doped carbon black or dyestuff or silane-modified
carbon black or dyestuff can react with the compound
containing hydroxyl groups or silane-modified compound
containing hydroxyl groups.
Si-containing carbon blacks known from WO 98/45361 or
DE 19613796 or metal-containing carbon blacks known
from WO 98/42778 can be used as the doped carbon black.
Inorganic and organic dyestuffs can be employed as the
dyestuff. Inorganic dyestuffs can be metal oxides, such
as, for example, (Zn,Co) . A1203, ZnO. (A1, Cr)203,
(Zn,Co)O. (Al,Cr)203, ZnO. (Al,Cr,Fe)203, MnO.Crz03,
(Mn, Co) O. (Cr, Fe) z03, CuO. Cr203, spinels or doped oxides,
or silicates, such as, for example, olivine, 2Co.Si02,
2(Ni,Zn).Si02, vanadium blue or Turkish blue.
Precipitated silicas, pyrogenic silicas, pyrogenic
oxides, silica sols, silica gels or naturally occurring
pigments can be used as the compounds containing
hydroxyl groups.
CA 02351162 2001-06-21
990234 RS/AL
4
If only the doped carbon black or dyestuff or the
compound containing hydroxyl groups is modified with
silane, bifunctional silanes, such as, for example, 3-
chloropropyltrialkoxysilane, isocyanate-silane,
tetraethyl orthosilicate (for example Dynasil~A),
tetramethyl orthosilicate (for example Dynasil~ M),
tetra-n-propyl silicate (for example Dynasil~ P),
tetrabutylglycol silicate (for example Dynasil~ BG),
ethyl polysilicate (for example Dynasil~ 40), 3-
aminopropyltrimethoxysilane (for example
Dynasylan~AMMO), 3-aminopropyltriethoxysilane (for
example Dynasylan~AMEO), N-aminoethyl-3-
aminopropyltrimethoxysilane (for example
Dynasylan~DAMO), triamino-functional
propyltrimethoxysilane (for example Dynasylan~TRIAMO),
3-mercaptopropyltrimethoxysilane (for example
Dynasylan~MTMO); 3-glycidyloxypropyltrimethoxysilane
(for example Dynasylan~GLYMO), 3-
glycidyloxypropyltriethoxysilane (for example
Dynasylan~GLYEO), 3-methacryloxypropyltrimethoxysila.ne
(for example Dynasylan~MEMO), 3-
acryloxypropyltrimethoxysilane, vinyltrichlorosilane
(for example Dynasylan~VTC), vinyltrimethoxysila.ne (for
example Dynasylan~(VTMO), vinyltriethoxysilane (for
example Dynasylan~VTEO), allyltrichlorosilane,
allyltrimethoxysilane, allyltriethoxysilane, N-(n-
butyl)-3-aminopropyltrimethoxysilane (for example
Dynasylan~1189), or 3-ureidopropyltriethoxysilane (for
example Dynasylan~2201/2220), can be used. For this,
the doped carbon black or dyestuff or the compound
containing hydroxyl groups is reacted with the silane.
The reaction can proceed according to the following
equation
CA 02351162 2001-06-21
990234 RS/AL
I I
-Si - OH + C-silane-A~ -Si - O-silane-A a.) Ink or
I I b.) Media
a.) Si-doped carbon black I coating
or b.) compound containing + -Si - OH
hydroxyl groups t
a.) Media coating or
b.) Ink
I I
- Si - O-silane - O-Si
i I
The functional group A can be a halogen, alkoxy, epoxy
5 or isocyanate group. If the doped carbon black or
dyestuff and the compound containing hydroxyl groups
are modified with silane, both the doped carbon black
or dyestuff and the compound containing hydroxyl groups
contain, after the modification, functional groups
which can react with one another. For example, the
doped carbon black or dyestuff and the compound
containing hydroxyl groups can be modified with the
following combinations of silanes:
~ alkoxyaminosilane, for example 3-
aminopropyltrimethoxysilane (for example Dynasylan~
AN~IO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO), or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO),
and alkoxyepoxysilane, for example 3-
glycidyloxypropyltrimethoxysilane (for example
Dynasylan~ GLYMO) or 3-glycidyloxypropyltriethoxysilane
(for example Dynasylan~ GLYEO),
~ alkoxyammonium chloride-silane, for example (3-
triethoxysilylpropyl)dimethyloctadecylammonium chloride
or (3-triethoxysilylpropyl)trimethylammonium chloride,
and sulfonatohydroxysilane, for example 3-
sulfonatopropyltrihydroxysilane,
CA 02351162 2001-06-21
990234 RS/AL
6
~ alkoxyaminosilane, for example 3-
aminopropyltrimethoxysilane (for example Dynasylan~
AN~IO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO), or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO)
and isocyanate-silane.
The reaction can proceed according to the following
equation
I I
-Si - OH + Gsilane-A--~ -Si - O-silane-A
I I
Si-doped carbon black Ink ~ I I
-Si - O-silane-silane-OSi -
I I
I I
-Si - OH + D-silane-B~--~ -Si - O-silane-B
I I
Compound containing Media coating
hydroxyl groups
The functional groups A and B can be anionic and
cationic groups, amino and epoxy groups or amino and
isocyanate groups.
(c)The ink can comprise a doped carbon black or dyestuff,
optionally modified with a silane, and the media
coating can comprise a polymer with functional groups.
The functional groups of the doped carbon black or
dyestuff or silane-modified carbon black or dyestuff
can react with the functional groups of the polymer.
If the doped carbon black or dyestuff is not modified
with silane, the polymer can contain functional groups
which can react with the doped carbon black or
dyestuff. The abovementioned compounds can be employed
as the doped carbon black or dyestuff. The polymer can
contain functional groups, such as, for example, epoxy,
CA 02351162 2001-06-21
990234 RS/AL
7
isocyanate, alkoxy or hydroxyl groups.
The reaction can proceed according to the following
equation
I I
-Si - OH + polymer-A ---~ -Si - O-polymer
I I
Si-doped carbon black Media coating
Ink
If the doped carbon black or dyestuff is modified with
silane, both the modified doped carbon black or
dyestuff and the polymer contain functional groups
which can react with one another. For example, the
doped carbon black or dyestuff can be modified with the
following silanes, it being necessary for the polymer
to have corresponding functional groups:
~ alkoxyammonium chloride-silane, for example (3-
triethoxysilylpropyl)dimethyloctadecylammonium chloride
or (3-triethoxysilylpropyl)trimethylammonium chloride,
and polymer with sulfonate groups,
~ sulfonatohydroxysilane, for example 3-
sulfonatopropyltrihydroxysilane,
and polymer with ammonium chloride groups,
~ alkoxyaminosilane, for example 3-
aminopropyltrimethoxysilane (for example Dynasylan~
ANaKO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO), or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO)
and polymer with epoxy groups,
~ alkoxyepoxysilane, for example 3-
glycidyloxypropyltrimethoxysilane (for example
Dynasylan~ GLYMO), or 3-glycidyloxypropyltriethoxysilane
CA 02351162 2001-06-21
990234 RS/AL
8
(for example Dynasylan~ GLYEO),
and polymer with amino groups,
~ alkoxyaminosilane, for example 3-
aminopropyltrimethoxysilane (for example Dynasylan~
ANIrIO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO), or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO)
and polymer with isocyanate groups or
~ isocyanate-silane,
and polymer with amino groups.
The reaction can proceed according to the following
equation
I I
-Si - OH + C-silane-Ate' -Si - O-silane-A Ink
I I
Si-doped carbon black
+ Polymer-B
Media coating
I
-Si - O-silane-polymer
I
The polymer can be a copolymer, block copolymer,
polyampholyte or comb polymer. The polymers are built up
here such that the abovementioned functional groups are
present or can be incorporated by polymer-analogous
reaction.The molecular weight Mw of the polymer can be
less than 100,000 g/mol, preferably less than
10,000 g/mol.
Copolymers based on (meth)acrylic acid with basic
(meth)-acrylates, such as dimethylaminoethyl
(meth)acrylate and dimethylaminopropyl (meth)-acrylamide
and quaternary ammonium compounds thereof and further
alkyl or aryl (meth)acrylates (for example C4_3o-alkyl
(meth)acrylates, cyclohexyl (meth)acrylate, benzyl
(meth)acrylate, phenylethyl (meth)acrylate),
CA 02351162 2001-06-21
990234 RS/AL
9
heterocyclic (meth)acrylates (for example
morpholinoethyl (meth)acrylate, N(2-
methacryloyloxyethyl)ethyleneurea) or hydroxy esters
(for example 2-hydroxyethyl (meth)acrylate,
hydroxypropyl (meth)acrylate) or alkyl polyethylene
glycol (200-2000) (meth)acrylates (for example
methoxypolyethylene glycol 750 methacrylate), can be
used. Water-soluble polymers based on (meth)acrylic
acid, which have dispersing or pigment-stabilizing
properties and moreover, by interaction with the carbon
black pigment, should prevent diffusion into the paper
surface, can be used as the polyampholytes. Graft
polymers with emulsifier properties, which are obtained
by copolymerization of hydrophobic macromonomers with
functionalized end groups with hydrophilic monomers (EP
0 728 780 B1), can be used as the comb polymers. The
macromonomers with a (meth)acryloyl end group are
prepared, for example, from C8_C3oalkyl methacrylates,
cyclohexyl methacrylate or benzyl methacrylate and then
with hydrophilic (meth)acrylates (for example
(meth)acrylic acid, (meth)acrylamide, 2-hydroxyethyl
(meth)-acrylate, hydroxypropyl (meth)acrylate,
dimethylaminoethyl (meth)acrylate and
dimethylaminopropyl(meth)acrylamide and quaternary
ammonium compounds thereof).
Block copolymers with the same monomer composition can
equally suitably be used.
Copolymers which are prepared from acrylamide monomers
and at least one of the monomers chosen from acrylic
acid, dimethylaminopropylamine,
dimethylaminopropylacrylamide (basic, neutral,
quaternized), dimethylaminoethyl acrylate or
dimethylaminoethyl methacrylate, can be used as the
polymers.
CA 02351162 2001-06-21
990234 RS/AL
(d) The ink can comprise a polymer with functional groups
and the media coating can comprise a compound which
contains hydroxyl groups and is optionally modified with
silane. The functional groups of the polymer can react
5 with the functional groups of the compound containing
hydroxyl groups or silane-modified compound containing
hydroxyl groups.
Precipitated silicas, pyrogenic silicas, pyrogenic
oxides, silica sols, silica gels or naturally occurring
10 pigments can be used as the compound containing hydroxyl
groups.
The polymer with the functional groups can bond the
carbon black or dyestuff physically or chemically. The
abovementioned compounds or metal sulfides, selenium
sulfides, metal powders, pigments or coloured pigments
can be employed as the carbon black or dyestuffs.
If the compound containing hydroxyl groups is not
modified with silane, the polymer can contain functional
groups which can react with the compound containing
hydroxyl groups. The polymer can contain functional
groups, such as, for example, epoxy, isocyanate, alkoxy
or hydroxyl groups.
The reaction can proceed according to the following
equation
i i
-Si - OH + Polymer-A --~ -Si - O-polymer
I I
Compound containing Ink
hydroxyl groups
Media coating
If the compound containing hydroxyl groups is modified
with silane, both the compound containing hydroxyl
groups and the polymer contain, after the modification,
CA 02351162 2001-06-21
990234 RS/AL
11
functional groups which can react with one another. For
example, the compound containing hydroxyl groups can be
modified with the following silanes, it being necessary
for the polymer to have corresponding functional groups:
~ alkoxyammonium chloride-silane, for example (3-
triethoxysilylpropyl)dimethyloctadecylammonium
chloride or (3-
triethoxysilylpropyl)trimethylammonium chloride, and
polymer with sulfonate groups,
~ sulfonatohydroxysilane, for example 3-
sulfonatopropyltrihydroxysilane,
and polymer with ammonium chloride groups,
~ alkoxyaminosilane, for example, 3-
aminopropyltrimethoxysilane (for example Dynasylan~
AMMO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO) or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO),
and polymer with epoxy groups,
~ alkoxyepoxysilane, for example 3-
glycidyloxypropyltrimethoxysilane (for example
Dynasylan~ GLYMO) or 3-
glycidyloxypropyltriethoxysilane (for example
Dynasylan~ GLYEO),
and polymer with amino groups,
~ alkoxyaminosilane, for example 3-
aminopropyltrimethoxysilane (for example Dynasylan~
AMMO), 3-aminopropyltriethoxysilane (for example
Dynasylan~ AMEO) or N-aminoethyl-3-
aminopropyltrimethoxysilane (for example Dynasylan~
DAMO),
and polymer with isocyanate groups or
CA 02351162 2001-06-21
990234 RS/AL
12
~ isocyanate-silane,
and polymer with amino groups.
The abovementioned compounds can be employed as the
polymers.
The reaction can proceed according to the following
equation
I I
-Si - OH + C-silane-A-~ -Si - O-silane-A Media
I I coating
Compound containing hydroxyl groups ~ + Polymer-B
Ink
I
-Si - O-silane-polymer
I
(e)The ink can comprise a modified carbon black with
-SiR~3_a~ (O-(CH2)n-CH3)a groups (n = 0 - 5, a = 1-3, R =
alkyl) and the media coating can comprise a compound
containing hydroxyl groups. The alkoxy groups of the
modified carbon black can react with the compounds
containing hydroxyl groups.
The modified carbon black with -SiR~3_a~ (O- (CH2 ) n-CH3 ) a
groups can be obtained by reaction of the carbon black
with
~ the corresponding azido compound,
~ a corresponding compound R-Sy-R, where y = 2-10 (DE
10012784.3) or
~ a corresponding compound which contains C-C double or
triple bond which is not a constituent of an aromatic
system, the C-C double or triple bond of which is
activated by at least on substituent, for example
-COOR, -CO-R, -CN, -SOZR, -S020R or -CO-X-CO-, (DE
19931314.8).
CA 02351162 2001-06-21
990234 RS/AL
13
Precipitated silicas, pyrogenic silicas, pyrogenic
oxides, silica sols, silica gels or naturally occurring
pigments can be used as the compound containing
hydroxyl groups.
The alkoxy groups of the modified carbon black can
react with the compound containing hydroxyl groups
after the printing.
The reaction can proceed according to the following
equation
/ H / N"~ '(~m~ (~'(~n'
~Of~ '~ ~'(~m'~ (Q'(~n~3~ / ~f~C
H H
or
+ sxt(~m~l(~-(~-~1~1~ oonkairing s~.~
+ R-(Q~m-Siy-~i~n-Q~y~ Meda ooading
/ H I I
(f) The ink can comprise an oligomer or polymer and a
crosslinking agent and the media coating can comprise
an oligomer or polymer, optionally a crosslinking
agent. The crosslinking agent can crosslink the
oligomer or polymer of the ink and additionally react
with the oligomer or polymer of the media coating.
Compounds with functional groups, for example C-C
double bonds, can be used as the oligomer or polymer.
CA 02351162 2001-06-21
990234 RS/AL
14
The functional groups can react with the crosslinking
agent. The crosslinking agent can be activated by air,
heat, light or UV.
(g) The ink and the media coating can comprise one or more
monomers and the ink and/or media coating can comprise
a polymerization initiator. The ink and the media
coating can be bonded by the polymers prepared by the
polymerization.
The polymerization initiator can be activated by air,
heat, light or W. In a particular embodiment of the
invention, the polymerization can be carried out by
autocatalysis, without a polymerization initiator.
Dimers, trimers or tetramers can be used as the
monomers.
The ink can also comprise further constituents, such as,
for example, water, solvents, polymer, cationic additives,
binders, such as, for example, starch, cellulose,
gelatine, casein, polyvinyl alcohol, polyvinylpyrrolidone,
styrene/butadiene copolymer or ethylene/vinyl acetate
copolymer, glass frit and other auxiliary substances.
The media coating can also comprise further constituents,
such as, for example, binders, pigment, wetting agents,
tinting dyestuffs, antistatics and other auxiliary
substances.
The ink jet process, for example, can be used as the
process for the production of the printed media coating.
The printing can be carried out at temperatures of 10 ~C to
200 ~C. A heat treatment, for example by a heated roller,
at 10~C to 300qC can optionally take place after the
printing, in order to allow the reaction or to bring it to
completion.
CA 02351162 2001-06-21
990234 RS/AL
The printed media coatings can be used for the production
of books, journals, posters, newspapers, textiles, articles
of glass, metal or ceramic, depending on the medium.
The printed media coatings according to the invention have
5 a higher water resistance, fastness to light, fastness to
wiping and an improved print quality. The printing can be
carried out at a higher printing speed.
CA 02351162 2001-06-21
990234 RS/AL
16
Examples
To evaluate the interactions between inks and coating
materials, coloristic measurements are carried out and the
improved fastness to wiping is evaluated.
For the inks described by way of example which are based on
pigment carbon blacks, the optical density D is determined
with a densitometer from Macbeth of the type RD 918.
The fastness to wiping of an ink - coating material
combination is estimated by the following method.
A modified K Control Coater from Erichson is used for the
newly developed test method. An ink according to the
invention described by way of example is knife-coated on to
the medium to be coated (paper, film etc.) and dried,
wetted with a defined amount of water and the water is
wiped over the area to be tested by operating the slide.
The optical densities before and after wiping are
determined as measurement values and a standardized rating
of the pigment discharge is given with a figure from 0
(complete discharge) - 9 (no discharge). The data of the
media coatings selected are assigned to the corresponding
example.
Example 1
Preparation of a carbon black dispersion
Distilled water is initially introduced into a dispersing
vessel and 7.5 ~ Lutensol AO 30 from BASF is slowly added
with the Ultra-Turrax running. When the Lutensol has
dissolved completely, 2.1~ Hypomer CG6 from ICI Surfactants
and 0.3~ AMP 90 from Angus Chemie are added. 15~ carbon
black FW18 from Degussa are then added in portions, the
dispersion is dispersed with the Ultraturrax (level 10) and
CA 02351162 2001-06-21
990234 RS/AL
17
thereafter the coarse contents are separated off in a
centrifuge.
A bead mill is employed for further homogenization of the
dispersion. The amount flowing through is 31/h at 3000 rpm.
To separate off bead fragments, the mixture is filtered
over a sieve of 100).tm mesh width and centrifuged at
4000 rpm.
Preparation of an ink
g 2-pyrrolidone, 5 g 1,2-propanediol and 4 g 1,5-
10 pentanediol are topped up with 65 ml water. 35 g of the
dispersion described above are then added, while stirring.
The ink obtained in this manner is then deaerated and
introduced into the cartridge.
Production of the media coating
0.8 g NaN02 are added to 50 g ink, while stirring. The ink
is investigated in respect of its fastness to wiping and
optical density by the test methods mentioned.
A paper which is modified with amino-functional groups by
the following process is used as the medium to be coated.
To prepare the brushing paints for the paper, polyvinyl
alcohol (PVA) is dissolved in the total amount of water at
approx. 95QC, the pigment (precipitated silica + Dynasilan~
AMEO from Sivento) is then incorporated at 500 to 1000 rpm
and the components are dispersed for half an hour at
3000 rpm. The brushing paints are adjusted to a solids
content of 18 ~. The example recipe comprises 100 parts of
pigment and 50 parts of Mowiol 28-99 (PVA from Clariant
GmbH). The solids content is 18~, the application weight is
approx. 10 g/m2. The viscosity is determined by the
Brookfield method, after stirring up. Thereafter, all the
brushing paints are used to knife-coat in each case 10
sheets by hand on an 80 g/m2 wood-free base paper, and the
CA 02351162 2001-06-21
990234 RS/AL
18
coated papers produced are calendered, weighed and then
subjected to the individual tests. The tests for
determination of the quality of the paper include a
printing test (printing a test image on an EPSON Stylus
color 800 and HP Deskjet 550) and a drying test
(determination of the drying time of 1 ~,1 water on the
paper coated with ink).
The optical density of the ink coating according to the
invention described above is 1.11. The difference from the
optical density after the wiping operation is 0.05. The
pigment discharge is rated as 8.
Example 2
Functionalization of a pigment carbon black
g of a carbon black doped with silicon (according to EP
15 0799866) are stirred into 100 ml methyl ethyl ketone, 1.5 g
Dynasylan~ Glymo from Sivento are added, and the mixture is
stirred for 12 hours at room temperature and then filtered
with suction. The carbon black obtained is then dried in a
drying cabinet at 100 ~C for eight hours.
The functionalized carbon black is incorporated into a
dispersion by the process described in example 1 and this
is converted into an ink. The ink is investigated in
respect of its fastness to wiping and optical density by
the test method mentioned.
A paper which is coated by the process described in example
1 is used as the medium to be coated.
The optical density of the corresponding coating is 1.23.
The difference from the optical density after the wiping
operation is 0.11. The pigment discharge is rated as 7.
CA 02351162 2001-06-21
990234 RS/AL
19
Example 3
Functionalization of a pigment carbon black
15 g of a carbon black doped with silicon (according to EP
0799866) are stirred into 100 ml methyl ethyl ketone, 1.5 g
Dynasylan~ 1161 (based on the active compound) from Sivento
are added, and the mixture is stirred for 12 hours at room
temperature and then filtered with suction. The carbon
black obtained is then dried in a drying cabinet at 100 ~C
for eight hours.
The functionalized carbon black is incorporated into a
dispersion by the process described in example 1 and this
is converted into an ink. The ink is investigated in
respect of its fastness to wiping and optical density by
the test method mentioned.
A paper which is coated by the process described in example
1 is used as the medium to be coated. In addition to the
constituents described, Polystabil 5312 from Stockhausen
was added.
The optical density of the corresponding coating is 1.20.
The difference from the optical density after the wiping
operation is 0.04. The pigment discharge is rated as 9.
Example 4
Preparation of a carbon black dispersion
The dispersion is prepared analogously to example 1. Tego
ABIL soft AF 100 from TEGO is used as the polymeric wetting
agent.
The dispersion is converted into an ink as described in
example 1.
A paper which is coated by the process described in example
1 is used as the medium to be coated. Instead of Dynasilan~
CA 02351162 2001-06-21
990234 RS/AL
AMEO, Dynasilan~ Glymo is incorporated into the paper
coating.
The optical density of the corresponding coating is 1.25.
The difference from the optical density after the wiping
5 operation is 0.03. The pigment discharge is rated as 9.
Example 5
Functionalization of a pigment carbon black
Variant 1:
A solution of 2 ml azidosilane Si250 from Degussa in 150 ml
10 acetone is added to 10 g carbon black FW1 from Degussa, the
mixture is stirred for 30 minutes at RT and the solvent is
then stripped off in vacuo. The carbon black is heat-
treated for two hours at 180~C. It is then washed with
acetone and dried in a drying cabinet at 105~C for eight
15 hours.
Variant 2
A solution of 2 ml azidosilane Si250 from Degussa in 150 ml
acetone is added to 10 g FW1 from Degussa and the solution
is stirred for six hours under irradiation from two
20 laboratory heating lamps and while cooling with water
(temp<50~C). It is then filtered with suction and the
residue is dried in a drying cabinet at 105$C for eight
hours.
The functionalized carbon blacks are incorporated into
dispersions by the process described in example 1 and these
are converted into inks. The ink is investigated in respect
of its fastness to wiping and optical density by the test
method mentioned.
Copy office paper from Kompass is used as the medium to be
coated.
CA 02351162 2001-06-21
990234 RS/AL
21
The optical density of the corresponding coating is 1.45
(variant 1) or 1.42 (variant 2). The difference from the
optical density after the wiping operation is 0.02 (variant
1) or 0.04 (variant 2). The pigment discharge is rated as 9
(variant 1) or 8 (variant 2).
Example 6
Functionalization of a pigment carbon black
2 g Si69 (bis(triethoxysilylpropyl)tetrasulfane) from
Degussa are dissolved in 150 ml toluene, 10 g FW1 are added
and the mixture is boiled under reflux for five hours. The
carbon black is then filtered off with suction and dried in
a drying cabinet at 105~C for eight hours. The yield is
determined with the aid of the amount of carbon black
obtained.
Yield: 75~
The functionalized carbon black is incorporated into a
dispersion by the process described in example 1 and this
is converted into an ink. The ink is investigated in
respect of its fastness to wiping and optical density by
the test method mentioned.
Copy office paper from Kompass was used as the medium to be
coated.
The optical density of the corresponding coating is 1.42.
The difference from the optical density after the wiping
operation is 0.04. The pigment discharge is rated as 9.
The inks described are investigated for their printability.
Printing tests are carried out by means of commercially
obtainable office inkjet printers. Printing takes place on
in each case one side on four different commercially
available ink jet papers and on copying paper immediately
and after a 5 min, 10 min, 20 min, 30 min and 60 min
CA 02351162 2001-06-21
990234 RS/AL
22
printing pause. A long-term test (printing of 20 pages
without a pause) and a refire test (investigation of the
writing properties of the ink after a 1, 3 and 7 day
printing pause) is furthermore carried out. The printed
images correspond to or exceed the results of the
corresponding original inks.
