High molecular weight colloids which control bleed

DETAILED DESCRIPTION What Is claimed Is: 1.
A process for controlling color bleed in inks employed in thermal ink-jet printing, comprising printing on a medium with an ink having the following composition: (a) a vehicle comprising (1) about 0.
05 to 0.
75 wt% of a high molecular weight colloid having a molecular weight of at least about 10,000, (2) at least one member selected from the group consisting of zwitterionic surfactants and non-ionic amphiphiles, present in an amount that is at least equal to its critical micelle concentration, and (3) about 0.
5 to 20 wt% of at least one organic solvent which supports the micelle formation of said at least one member; (b) about 0.
1 to 10 wt% of at least one water-soluble dye dissolved therein; and (c) the balance water.
2.
The process of claim 1 wherein said high molecular weight colloid is selected from the group consisting of alginic acid, mannomuronic acid, carrageenan, guar and xanthan gums, dextran, chitin, chitosan, and carboxymethylcellulose.
3.
The process of claim 2 wherein said alginic acid is present as a salt thereof, having a molecular weight of about 12,000 to 80,000.
4.
The process of claim 2 wherein said carrageenan has a molecular weight ranging from about 300,000 to 500,000.
5.
The process of claim 2 wherein said carboxymethylcellulose comprises a low molecular weight form of carboxylated cellulose, having a molecular weight of about 100,000.
6.
The process of claim 1 wherein said amphoteric surfactants are pH-sensitive surfactants selected from the group consisting of N,N-dimethyl-N-dodecyl amine oxide, N,N-dimethyl-N-tetradecyl amine oxide, N,N-dimethyl-N-hexadecyl amine oxide, N,N-dimethyl-N-octadecyl amine oxide, N,N-dimethyl-N-(Z-9-octadecenyl)-N-amine oxide, N-dodecyl-N,N-dimethyl glycine.
7.
The process of claim 1 wherein said organic solvent is selected from the group consisting of glycols, diols, glycol esters, glycol ethers, long chain alcohols, sulfolane, esters, ketones, lactones, and glycerols, and derivatives thereof and mixtures thereof