Patent ID: 7045002
Filing Date: 2006-05-16
Classification: B41J,C09D

Abstract:
1. An ink set of mutually interactive inks comprising at least four inks selected from categories (a)–(d) as follows: (a) aqueous anionic ink with a relative high pKa comprising a colorant and aqueous vehicle; (b) aqueous anionic ink with a relative low pKa, comprising a colorant and aqueous vehicle, which is adjusted to a pH below the pKa of any ink in the set from category a; (c) aqueous non-quarternized cationic ink comprising colorant and aqueous vehicle and (d) aqueous quarternized cationic ink comprising colorant and aqueous vehicle, wherein at least one ink from each category (a)–(d) is present in the set, no more than three inks from any one category are present in the set, and all inks from any one category further comprise complementary incompatibility ingredients so as to be mutually interacting with one another by an aqueous phase change mechanism.