Electrophotographic liquid developer
AssigneeSumitomo Chemical Company, Limited
InventorsSeiji Hotta, Hitoshi Kawahara, Minoru Hatori, Fumio Koseki
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AssigneeSumitomo Chemical Company, Limited
InventorsSeiji Hotta, Hitoshi Kawahara, Minoru Hatori, Fumio Koseki
Estimating the term…
An electrophotographic developer containing a carrier, a resinous, waxy or varnish compound and as a color component, a phosphotungstomolybdic acid lake of a mixture of an indolenine dye of the formula (I): ##STR1## wherein A is a benzene or naphthalene nucleus, R.sub.1 is a C.sub.1 -C.sub.4 alkyl group R.sub.2 and R.sub.3 are respectively a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, R.sub.4 and R.sub.5 are respectively a hydrogen atom, a C.sub.1 -C.sub.4 alkyl, .beta.-hydroxyethyl, .beta.-chloroethyl, .beta.-cyanoethyl, aralkyl, cycloalkyl, phenyl, or substituted phenyl. Y is a hydrogen or halogen atom, or a nitro, alkyl, alkoxy, carbalkoxy or acetamido group, and X.sup.- is a colorless anion, with a xanthene dye of the formula (II): ##STR2## wherein R.sub.6, R.sub.7, R.sub.10, R.sub.11 and R.sub.12 are respectively a hydrogen atom or a C.sub.1 -C.sub.4 alkyl group, R.sub.8 and R.sub.9 are respectively a C.sub.1 -C.sub.4 alkyl group, and Y.sup.- is a colorless anion.
An electrophotographic liquid developer holding positive charges in a stable state, which consists essentially of (1) a carrier which is a high electrical resistivity liquid having above 10.sup.10 .OMEGA.cm of volume resistivity, (2) a resinous, waxy or varnish compound selected from the group consisting of oil-modified alkyd resins, rosin-modified phenol-formaldehyde resins, polyhydric alcohol esters of hydrogenated rosin, polyacryl ester resins, polymethacryl ester resins, polyvinyl acetate and polystyrene, and (3) as a color component, a phosphotungstomolybdic acid lake of a mixture of an indolenine dye selected from the group consisting of:
Dependencies are inferred from the claim text.