Patent GB-1382589-A (GB)
Title: Liquid developer for use in electrostatic photography
IPC: G03G9/13
Filed: 1971-12-23
Abstract: 1382589 Cyclorubber or grafted cyclorubber compositions RICOH KK 23 Dec 1971 [29 Dec 1970] 60098/71 Headings C3G C3P and C3Q [Also in Division G2] A liquid developer for use in electrostatic photography comprises a dispersion in an organic liquid of high electrical resistance of pigment or dye particles whose surface is coated with a resin, said resin comprising: (A) a cyclorubber in admixture with (a) a copolymer obtained by copolymerizing at least two monomers, the portion of the copolymer resulting from polymerization of one of said monomers being soluble in said organic liquid and the portion of the copolymer derived from the other said monomer being insoluble in said organic liquid; or (b) a graft copolymer obtained by graft polymerizing a polymer or copolymer, insoluble in said organic liquid, with a monomer which in its polymerized form in said graft copolymer is soluble in said organic liquid; or (B) a cyclorubber graft copolymer which has been obtained by graft polymerizing a cyclorubber with a monomer which in its polymerized form in said cyclorubber graft copolymer is soluble in said organic liquid. The polymer or copolymer in (A)(b) or cyclorubber in (B) may be grafted also with a monomer which in its polymerized form in the graft copolymer is insoluble in the said organic liquid. Examples are given in which dispersions in paraffinic hydrocarbons, optionally containing toluene, comprise carbon black and (1) cyclorubber and lauryl methacrylate-acrylate acid copolymer; (2) cyclorubber-lauryl methacrylate graft copolymer and copolymer as in (1); (3) graft copolymer and copolymer as in (2) and also styrene-butadiene copolymer grafted with 2- ethylhexyl methacrylate; (4) cyclorubber, lauryl methacrylate/p-nitrostyrene copolymer, grafted styrene-butadiene copolymer grafted with lauryl methacrylate and a blue pigment; (5) cyclorubber and the grafted copolymer specified in (3); (6) cyclorubber, the grafted styrenebutadiene copolymer specified in (4) and a dye; (7) cyclorubber and a styrene-butadiene copolymer grafted with tridecyl methacrylate; (8) cyclorubber and a styrene-butadiene rubber grafted with n-octyl methacrylate; (9) cyclorubber, a grafted styrene-butadiene copolymer as in (3) and lauryl methacrylate-acrylic acid copolymer; (10) cyclorubber and the grafted styrene-butadiene copolymer as in (3); (11) to (14) cyclorubber grafted with 2-ethylhexyl methacrylate, tridecyl acrylate, vinyl oleate or decyl vinyl ether; (15) cyclorubber/2-ethylhexyl methacrylate graft copolymer and n-octyl methacrylate-acrylic acid copolymer; (16) cyclorubber-lauryl acrylate graft polymer and vinyl laurate-diethyl-aminoethyl methacrylate copolymer; (17) cyclorubber-vinyl laurate graft copolymer and lauryl vinyl ether/p-dimethylaminostyrene copolymer; (18) cyclorubberlauryl methacrylate-acrylic acid graft copolymer; (19) cyclorubber/2-ethylhexyl methacrylate/dimethylaminoethyl methacrylate graft copolymer; (20) cyclorubber/tridecyl acrylate/ 2-vinyl pyridine graft copolymer; (21) vinyl toluene-methyl methacrylate copolymer grafted with vinyl laurate and p-dimethylaminostyrene and cyclorubber; (22) styrene-butadiene copolymer grafted with 2-ethylhexyl methacrylate and acrylic acid and cyclorubber; (23) vinyl toluene/2-ethylhexyl acrylate copolymer grafted with stearyl vinyl ether and p-nitrostyrene and cyclorubber; (24) vinyl toluene/n-butyl methacrylate copolymer grafted with stearyl vinyl ether and 2-hydroxyethyl methacrylate and cyclorubber; (25) n-octyl vinyl ether/p-ethylamino styrene copolymer and cyclorubber; (26) n-hexyl vinyl ether/3-hydroxypropyl methacrylate copolymer and cyclorubber; (27) cyclorubber, styrene-butadiene copolymer grafted with vinyl laurate and n-octyl vinyl ether/dimethylaminoethyl methacrylate copolymer; (28) cyclorubber grafted with n-hexyl vinyl ether and 2-vinyl pyridine. The liquid developers are tested (see Division G2).