Aqueous pigment dispersions based on polyurethane dispersants having components to interact with cellulose

An aqueous pigment dispersion comprising a colorant and a polyurethane dispersant, wherein said polyurethane dispersant comprises at least one compound of the general structure of Formula I:

• each Y is independently O, S or NR4;
• each W is N, O or S;
• n is an integer from 2 to 30;
• each R1 is independently C1-C20 alkyl optionally substituted with one or more R5, OR6, SR6 or NR7R8, or C6-C40 aryl optionally substituted with one or more R5, OR6, SR6 or NR7R8;
• each R2 is comprised of difunctional isocyanate reactants Z1, Z2 and Z3, wherein
• Z1 is a difunctional isocyanate reactant substituted with an aqueous dispersing ionic group, and Z1 is present in between 5 to 40 weight percent of total weight of the polyurethane dispersant;
• Z2 is a difunctional or trifunctional isocyanate reactant selected from the group consisting of diol, diamine, amino alcohol, diamine alcohol, and amino dialcohol, and Z2 is present in between 0 to 40 weight percent of total weight of the polyurethane dispersant;
• and
• Z3 is a difunctional isocyanate reactant substituted with R3, and Z3 is present in between 5 to 40 weight percent of total weight of the polyurethane dispersant;
• and
• each R3 is independently a monocyclic or bicyclic heterocycle containing N, S or O atoms on the ring bonding via a carbon or heteroatom to Y or Z2 either directly or via a linking group containing 1-10 carbon atoms, wherein said heterocycle is selected from the group consisting of imidazolidinone, oxazolidinone, thiazolidinone, triazole, thiazole, pyridazine, and glycoside, and wherein the carbon atoms on the ring of said heterocycle are optionally substituted with one or more R5, OR6, SR6 or NR7R8, and the N atom or atoms on the ring of said heterocycle are optionally substituted with R5 or —R9OR6;
• each R5 is independently C1-C20 alkyl, C3-C20 cycloalkyl or C6-C40 aryl;
• each R6 is independently H, C1-C20 alkyl, C3-C20 cycloalkyl or C6-C40 aryl;
• and
• each R7 and R8 are independently H, C1-C20 alkyl, C2-C20 cycloalkyl or C6-C40 aryl;
• and
• each R9 is C1-C5 alkyl.