Patent ID: 6475688
Filing Date: 2002-11-05
Classification: G03G

Abstract:
An electrophotographic toner comprising a resinous composition for toner and a colorant whereinthe resinous composition comprises a copolymer including a lower molecular weight component having a peak at molecular weight of 3,000 to 50,000 and a higher molecular weight component having a peak at molecular weight of 100,000 to 5,000,000, the copolymer comprising a vinyl based copolymer comprised of a styrene based monomer and an acrylic or methacrylic acid ester based monomer as structural units, and the toner comprises a fatty acid ester represented by at least one of the general formulas (1-1) through (1-4), and a carboxylic acid represented by the general formula (2), R1COOR2â€ƒâ€ƒGeneral Formula (1-1) in the formula, one or both of R1 and R2 represent an aliphatic group having not less than 14 carbon atoms and when either R1 or R2 represents an aliphatic group having not less than 14 carbon atoms, the other group represents an alkyl group having not more than 14 carbon atoms, a cycloalkyl group, an alkenyl group, or an aralkyl group, [R1COOâ€”(CH2)n]aâ€”Câ€”[(CH2)mâ€”OCOR2]bâ€ƒâ€ƒGeneral Formula (1-2) in the formula, a and b each represents an integer of 0 to 4; a+b is 4; R1 and R2 each represents an organic group having from 1 to 40 carbon atoms; the difference in the number of carbon atoms between R1 and R2 is to be at least 3; m and n each represents an integer of 0 to 25; and m and n are not 0 at the same time, â€ƒ[R1COOâ€”(CH2)n]aâ€”Câ€”[(CH2)mâ€”OH]bâ€ƒâ€ƒGeneral Formula (1-3)in the formula, a represents an integer of 1 to 3; b represents an integer of 1 to 3; a+b is 4; R1 represents an organic group having from 1 to 40 carbon atoms; m and n each represents an integer of 0 to 25; and m and n are not 0 at the same time, [R1COOâ€”(CH2)n]aâ€”C(R3)kâ€”[CH2]mâ€”OCOR2]bâ€ƒâ€ƒGeneral Formula (1-4) in the formula, a and b each represents an integer of 0 to 3; a+b is 1 to 3, R1 and R2 each represents an organic group having from 1 to 40 carbon atoms; the difference in the number of atoms between R1 and R2 is at least 3; R3 represents a hydrogen atom or an organic group having at least 1 carbon atom with proviso, when a+b is 2, either one of R3 represents an organic group having at least 1 carbon atom; k represents an integer of 1 to 3; m and n each represents an integer of 0 to 25; and m and n are not 0 at the same time, R4â€”COOHâ€ƒâ€ƒGeneral Formula (2) in the formula, R4 represents a saturated or unsaturated aliphatic group having at least 13 carbon atoms. where in content of the carboxylic acid represented by the general formula (2) is 0.001 to 5 percent by weight with respect to the resinous component.