Patent ID: 7449217

Claim:
A method of enhancing humid fastness and fade fastness of ink jet images printed on print substrates coated with silica-based compositions for print applications, said method comprising the following steps in the sequence recited: (a) providing a quantity of silica; (b) coating said substrate with said silica; and (c) modifying said silica by reacting it with an organo silane having the formula SiR 4 , where (i) at least one R is selected from the group consisting of halogen and alkoxy, (ii) at least one other R is an active group selected from the group consisting of (1 ) linear or branched alkyl groups up to C 22 , represented by the formula —CH 2 —(CH 2 )n—CH 3 , where n is an integer up to 20; (2) (a) cyano, (b) carboxy, (c) sulfonate, (d) halogen, (e) epoxy, (f) furfuryl, (g) pyridyl, and (h) imidazoline derivative-substituted alkyl groups up to C 8 ; (3) cycloalkyl groups and their alkyl derivatives, cycloalkenyl groups and their alkyl derivatives, and epoxycycloalkyl groups up to eight carbon atoms and their alkyl derivatives; (4) phenyl groups and their alkyl derivatives and phenoxy groups and their alkyl derivates; (5) (a) carboxy, (b) sulfonate, and (c) halogen substituted counterparts of (4); and (6) mono- ethyleneimine and poly-ethyleneimine groups, and wherein the active group is other than a quaternary ammonium group, and (iii) any remaining R is a lower alkyl group having from 1 to 3 carbon atoms.