Production of polyester and elecrophotographic toner containing the same
AssigneeKao Corporation
InventorsKuniyasu Kawabe, Shinichiro Yasuda, Hideyo Nishikawa
Life of this patent
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Abstract
A polyester for use as an electrophotographic toner composition is obtained by copolycondensation of (a) a diol component of polyoxyalkylene-bis(4-hydroxyphenyl)propane and (b) an acid component, improved by incorporating into the acid component a copolymer of styrene or a derivative thereof and a carboxylic vinyl monomer. A copolymer of an unsaturated aliphatic hydrocarbon and an unsaturated carboxylic acid and a polymer and copolymer of an unsaturated carboxylic acid may be used. The toner is improved in the prevention of off-set in the fixation step.
Claims15
A toner composition, which comprises:
- a polyester produced by a process of copolycondensing:
- (a) a diol component of the formula (I):
- ##STR9## wherein R is an ethylene or propylene group and x and y are each an integer of at least 1, the total sum of x and y being 2 to 7 on the average, with
- (b) an acid component of a polycarboxylic acid, an anhydride thereof or a lower alkyl ester thereof, said acid component containing
- (II) a polycarboxylic copolymer of a styrene compound selected from alpha-methylstyrene and a compound of the formula (IIa):
- ##STR10## wherein R.sup.1 is hydrogen or a hydrocarbon group having 1 to 3 carbon atoms,
- and a carboxylic group-containing vinyl monomer of the formula (IIb), an anhydride thereof or a lower alkyl ester thereof:
- ##STR11## wherein R.sup.2 and R.sup.3 are each hydrogen, methyl or a carboxyl group;
- or
- (III) a copolymer of an unsaturated aliphatic hydrocarbon (IIIa) having 2 to 21 carbon atoms and an unsaturated carboxylic acid (IIIb);
- or
- (IV) a polymer or copolymer of an unsaturated carboxylic acid (IIIb);
- and a coloring matter.
The composition of claim 20, wherein the unsaturated carboxylic acid (IIIb) is selected from the group consisting of maleic acid, fumaric acid, acrylic acid, methacrylic acid, and itaconic acid.
A toner composition, which comprises:
- a polyester comprising
- (a) a diol component of the formula (I):
- ##STR13## wherein R is an ethylene or propylene group and x and y are each an integer of at least 1, the sum of x and y being 2 to 7 on the average;
- and
- (b) an acid component of a polycarboxylic acid, an anhydride thereof or a lower alkyl ester thereof, said acid component containing
- (II) a polycarboxylic copolymer of a styrene compound selected from alpha-methylstyrene and a compound of the formula (IIa):
- ##STR14## wherein R.sup.1 is hydrogen or a hydrocarbon group having 1 to 3 carbon atoms,
- and a carboxylic group-containing vinyl monomer of the formula (IIb), an anhydride thereof or a lower alkyl ester thereof:
- ##STR15## wherein R.sup.2 and R.sup.3 are each hydrogen, methyl or a carboxyl group;
- or
- (III) a copolymer of an unsaturated aliphatic hydrocarbon (IIIa) having 2 to 21 carbon atoms and an unsaturated carboxylic acid (IIIb);
- or
- (IV) a polymer or copolymer of an unsaturated carboxylic acid (IIIb);
- and
- a coloring matter.
Dependencies are inferred from the claim text.