Modification of pigment charge characteristics
AssigneeXerox Corporation
InventorChin H. Lu
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Abstract
A toner composition comprised of a resin and a pigment coated with a nitrogen containing compound thereby causing a change in the charge characteristics of the pigment, the nitrogen containing compound being selected from the group consisting of (a) quaternary ammonium compounds of the formula: ##STR1## wherein R is hydrogen, hydrocarbon radicals containing from 1 to about 22 carbon atoms, or mixtures thereof, and A is an anion selected from sulfate, sulfonate, nitrate, borate, chlorate, and halogen; (b) primary, secondary, or tertiary amines of the formula: ##STR2## wherein R is an aliphatic radical containing from about 8 to about 22 carbon atoms, and R.sub.1 and R.sub.2 are hydrocarbon radicals containing from 1 to about 22 carbon atoms; and (c) an alkyl pyridinium compound, and its hydrates.
Claims21
A positively charged dry electrophotographic developer composition comprised of a resin, a carrier, and as a pigment carbon black precoated with a nitrogen containing compound, the nitrogen containing compound being selected from the group consisting of
- (a) quaternary ammonium compounds of the formula:
- ##STR6## wherein R is hydrogen, hydrocarbon radicals containing from 1 to about 22 carbon atoms, or mixtures thereof, and A is an anion selected from sulfate, sulfonate, nitrate, borate, chlorate, and halogen;
- (b) primary, secondary, or tertiary amines of the formula:
- ##STR7## wherein R is an aliphatic radical containing from about 8 to about 22 carbon atoms, and R.sub.1 and R.sub.2 are hydrocarbon radicals containing from 1 to about 22 carbon atoms;
- and
- (c) an alkyl pyridinium compound, whereby the coated carbon black pigment is positively charged.
A positively charged dry electrophotographic developer composition comprised of a resin, a carrier, and as a pigment, carbon black coated with an alkyl substituted imidazoline.
Dependencies are inferred from the claim text.