Aqueous pigmented inks for ink jet printers

Claim 2

An aqueous ink jet ink composition comprising: a) an aqueous carrier medium; b) pigment particles stabilized by an AB or BAB block copolymer; and c) a surfactant; wherein said ink composition, when printed on a substrate dries at a faster rate than the same ink absent the surfactant.

Claim 3

The ink of claim 1, wherein the AB or BAB block copolymer comprises: a) an A segment comprising a hydrophobic homopolymer or copolymer of an acrylic monomer having the formula CH.sub.2 ═C(X)(Y) wherein X is H or CH 3 ; and Y is C(O)OR 1 , C(O)NR 2 R 3 , or CN, wherein R 1 is an alkyl, aryl, or alkylaryl group having 1 to 20 carbon atoms, and R 2 and R 3 are hydrogen or an alkyl, aryl, or alkylaryl group having 1 to 9 carbon atoms; said A segment having an average molecular weight of at least approximately 300 and being water insoluble; and (b) segment comprising a hydrophilic polymer, or salt thereof, of (1) an acrylic monomer having the formula CH.sub.2 ═C(X)(Y.sup.1), wherein X is H or CH 3 ; and Y 1 is C(O)OH, C(O)NR 2 R 3 , C(O)OR 4 NR 2 R 3 or C(O)OR 5 ; wherein R 2 and R 3 are hydrogen or an alkyl, aryl, or alkylaryl group having 1 to 9 carbon atoms; R 4 is an alkyl diradical having 1 to 5 carbon atoms; and R 5 is an alkyl diradical having 1 to 20 carbon atoms and optionally containing one or more hydroxyl or ether groups; or (2) a copolymer of the acrylic monomer of (1) with an acrylic monomer having the formula CH.sub.2 ═C(X)(Y) where X and Y are the substituent groups defined for said A segment; said B segment having an average molecular weight of at least approximately 300 and being water soluble, with the proviso that said B segment(s) constitute approximately 10 to 90% of said block copolymer, by weight.

Claim 4

The ink of claim 1 or 2, wherein the surfactant is anionic or non-ionic.

Claim 5

The ink of claim 1 or 2, wherein the surfactant is present in an amount of from about 0.1% to about 10% by weight of the total ink composition.

Claim 6

The ink of claim 3, wherein the surfactant is selected from the group of polyalkyleneoxide modified polydimethyl-siloxane, polyethylene oxide, octylphenoxy polyethoxy ethanol, dioctyl ester of sodium sulfosuccinic acid, dihexyl ester of sodium sulfosuccinic acid, and mixtures thereof.

Claim 7

The ink of claim 2, wherein the B segment comprises approximately 25 to 65%, by weight, of said block copolymer.

Claim 8

The ink of claim 2, wherein the B segment of said block copolymer is neutralized with a neutralizing agent selected from the group of organic bases, alkanolamines, alkali metal hydroxides, and mixtures thereof.

Claim 9

The ink of claim 2, wherein the B segment of said block copolymer is a homopolymer or copolymer prepared from at least one monomer selected from the group of methacrylic acid, acrylic acid, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, t-butylaminoethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylaminopropyl methacrylamide, methacrylamide, acrylamide, and dimethylacrylamide.

Claim 10

The ink of claim 8, wherein the B segment of said block copolymer is a homopolymer or copolymer of methacrylic acid or dimethylaminoethyl methacrylate.

Claim 11

The ink of claim 2, wherein the A segment of said block copolymer is a homopolymer or copolymer prepared from at least one monomer selected from the group of methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, lauryl methacrylate, stearyl methacrylate, phenyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, 2-ethoxyethyl methacrylate, methacrylonitirile, 2-trimethylsiloxyethyl methacrylate, glycidyl methacrylate, p-tolyl methacrylate, sorbyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, lauryl acrylate, stearyl acrylate, phenyl acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate acrylonitrile, 2-trimethyl-siloxyethyl acrylate, glycidyl acrylate, p-tolyl acrylate, and sorbyl acrylate.

Claim 12

The ink of claim 10, wherein the A segment of said block copolymer is a homopolymer or copolymer of methyl methacrylate, n-butyl methacrylate, or 2-ethylhexyl methacrylate.

Claim 13

The ink of claim 1, wherein said aqueous carrier medium comprises water and a polyhydric alcohol.

Claim 14

The ink of claim 1, wherein said aqueous carrier medium comprises at least 60% water, by weight.

Claim 15

The ink of claim 1, wherein the pigment particles have a size of approximately 0.01 to 5 microns.