Polymers for inkjet ink compositions

Abstract

Disclosed herein are polymers, which can be incorporated in pigment dispersions and inkjet ink compositions, comprising first monomers selected from ethylenically unsaturated hydrophobic monomers, and second monomers selected from maleic anhydride, maleic acid, and salts, esters, imides, and amides thereof. The polymers can have a portion of the second monomers functionalized with at least one organic group having a calcium index value greater than or equal to a calcium index value of phenylphosphonic acid. Additionally and/or alternatively, the at least one polymer can be crosslinked via the second monomers. Dispersions and inkjet ink compositions comprising such polymers can also further comprise at least one pigment and a liquid vehicle. Also disclosed are methods of making such polymers.

1 - 97 . (canceled) 
     
     
         98 . A method of making a polymer comprising,
 (a) combining:
 (i) at least one polymer comprising first monomers selected from ethylenically unsaturated hydrophobic monomers, and second monomers selected from maleic anhydride, maleic acid, and salts, esters, imides, and amides thereof, wherein the ethylenically unsaturated hydrophobic monomers comprise the formula CH 2 ═CR 1 R 2 , where R 1  and R 2  are independently selected from H, C 1 -C 12  alkyl, C 5 -C 20  aryl, and C 6 -C 20  alkaryl, and the carbon atoms of R 1  and R 2  can be optionally substituted with at least one heteroatom selected from O, N, and S, and 
 (ii) at least one crosslinking agent selected from epoxy-containing compounds; and 
   (b) forming the polymer.   
     
     
         99 . The method of  claim 98 , wherein the at least one crosslinking agent further comprises boric acid. 
     
     
         100 . The method of  claim 98 , wherein prior to or simultaneous with the combining the at least one polymer with at least one crosslinking agent, the method further comprises hydrolyzing the at least one polymer. 
     
     
         101 . The method of  claim 98 , wherein the second monomers are selected from maleic anhydride, maleic acid, and salts thereof. 
     
     
         102 . The method of  claim 98 , wherein the at least one crosslinking agent selected from epoxy-containing compounds reacts with carboxylate-containing groups of the second monomers. 
     
     
         103 . The method of  claim 98 , wherein the epoxy-containing compounds are selected from di- and tri-glycidyl ether compounds. 
     
     
         104 . The method of  claim 98 , wherein the epoxy-containing compounds are selected from trimethylolpropane triglycidyl ether. 
     
     
         105 . The method of  claim 98 , wherein the polymer formed in (b) is crosslinked through carboxylate groups of the second monomers. 
     
     
         106 . The method of  claim 98 , wherein the polymer formed in (b) is crosslinked through at least 10% of carboxylate groups of the second monomer. 
     
     
         107 . The method of  claim 98 , wherein the polymer formed in (b) is crosslinked via at least one linkage selected from ester linkages. 
     
     
         108 . The method of  claim 98 , wherein the ethylenically unsaturated hydrophobic monomers comprise the formula CH 2 ═CR 1 R 2 , wherein R 1  and R 2  are independently selected from H, C 1 -C 12  alkyl, C 5 -C 20  aryl, C 6 -C 20  aralkyl, and C 6 -C 20  alkaryl. 
     
     
         109 . The method of  claim 98 , wherein the ethylenically unsaturated hydrophobic monomers are selected from styrene, α-methyl styrene, ethylene, propylene, 1-butylene, isobutylene, butadiene, and methyl vinyl ether. 
     
     
         110 . The method of  claim 98 , wherein the ethylenically unsaturated hydrophobic monomers are selected from styrene. 
     
     
         111 . The method of  claim 98 , wherein the polymer formed in (b) has an acid number ranging from 50 to 325. 
     
     
         112 . The method of  claim 98 , wherein the polymer formed in (b) has an acid number ranging from 90 to 325. 
     
     
         113 . The method of  claim 98 , wherein the second monomers are present in the at least one polymer in an amount ranging from 10 to 60 mol % relative to the at least one polymer. 
     
     
         114 . The method of  claim 98 , wherein the first monomers are present in the at least one polymer in an amount ranging from 40 to 90 mol % relative to the at least one polymer. 
     
     
         115 . The method of  claim 98 , wherein the at least one polymer disperses a pigment to form a polymer-dispersed pigment, and the combining (a) comprises combining the polymer-dispersed pigment with the at least one crosslinking agent. 
     
     
         116 . The method of  claim 115 , wherein the pigment is unmodified. 
     
     
         117 . The method of  claim 115 , wherein the pigment is self-dispersed.