Patent ID: 6756170
Filing Date: 2004-06-29
Classification: G03G

Abstract:
An electrostatic image developing toner comprising at least a binder resin and a releasant, wherein the binder resin comprises a petroleum resin and a styrene-based copolymer or styrene-based homopolymer in an amount of 5:5 to 7:3 by weight in terms of the ratio of the petroleum resin:styrene-based copolymer or styrene-based homopolymer and has the maximum molecular weight value (PL) based on the petroleum resin in a range of from 5Ã—102 to 2Ã—103 and the maximum molecular weight value (PH) based on the styrene-based copolymer or styrene-based homopolymer in a range of from 1Ã—105 to 4.5Ã—105 in the chromatogram obtained by measuring the binder resin through gel permeation chromatography, HPL:HM:HPH=25 to 65:1:20 to 40, in which HPL represents the height of the maximum molecular weight value PL based on the petroleum resin in the chromatogram obtained by measuring the binder resin through gel permeation chromatography, HPH represents the height of the maximum molecular weight value PH based on the styrene-based copolymer or the styrene-based homopolymer in the chromatogram obtained by measuring the binder resin through gel permeation chromatography, and HM represents the minimum height between the two maximum values, and the releasant is a wax having a melt viscosity at 140Â° C. of 102 mPa/s (cp) or less and is added in an amount of 1 to 7 parts by weight per 100 parts by weight of the toner.