CPC C09D 11/033 (2013.01) [C09D 11/037 (2013.01); C09D 11/102 (2013.01); C08L 1/02 (2013.01); C08L 75/04 (2013.01)] | 14 Claims |
1. An alcohol-soluble, printing ink composition comprising:
(a) at least one colorant;
(b) a binder comprising an alcohol-soluble polyurethane;
(c) a solvent system comprising at least about 50% by weight of an alcohol based on the total weight of the solvent system,
wherein the solvent system comprises a solvent comprising a mixture of at least one alcohol and water; and
(d) a cellulose alkylate selected from the group consisting of cellulose acetate propionate and cellulose acetate butyrate,
wherein the cellulose alkylate/alcohol-soluble polyurethane weight ratio is between 1/4.5 to 1/6.25,
wherein the cellulose alkylate has (i) a hydroxyl group content of 5.1% to 7.1% by weight, (ii) an acetyl group content of 0.05% to about 0.65% by weight, both based on the weight of the cellulose alkylate, and (iii) a number-average molecular weight (Mn) of 7,000 to 13,000 g/mol, and
wherein the alcohol-soluble, printing ink composition has a color saturation CIE as determined by LCH method, which is higher than that of an alcohol-soluble, printing ink composition which has the same composition except for the cellulose alkylate having been replaced by nitrocellulose (NC).
|