Resin for toner and toner
AssigneeCanon Kabushiki Kaisha
InventorsHayato Ida, Takashi Hirasa, Junichi Tamura, Yuya Chimoto, Takaho Shibata, Daisuke Yamashita
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Abstract
The present invention provides a crystalline polyester resin which has sharp melt property, can achieve both fixing performance and blocking property and has excellent development durability, in which the crystalline polyester resin for toner which has a Young's modulus as measured by an ultramicro durometer at 25° C. of at least 2 GPa and a melting point of at least 60° C. and not more than 125° C.
Claims19
A crystalline polyester resin, comprising a condensation polymerization product of:
- (i) a dicarboxylic acid component containing at least one compound selected from the group consisting of terephthalic acid and terephthalic acid derivatives;
- and
- (ii) a diol component containing at least one compound selected from the group consisting of 2-methyl-1,3-propanediol and derivatives of 2-methyl-1,3-propanediol,
- said crystalline polyester resin having a weight-average molecular weight as measured by gel permeation chromatography of 5000 to 50000, and
- a Young's modulus as measured by an ultramicro durometer at 25° C. of at least 2 GPa and a melting point of 60° C. to 125° C.
A toner comprising a crystalline polyester resin, the crystalline polyester resin for toner, having a Young's modulus as measured by an ultramicro durometer at 25° C. of at least 2 GPa and a melting point of 60° C. to 125° C.
A method for producing toner comprising a crystalline polyester resin, the crystalline polyester resin, having a Young's modulus as measured by an ultramicro durometer at 25° C. of at least 2 GPa and a melting point of 60° C. to 125° C., the method comprising:
- a resin dissolution step of dissolving a polyester resin in an organic solvent to obtain a resin composition,
- the polyester resin being obtained by condensation polymerization of a dicarboxylic acid component containing at least one compound selected from the group consisting of terephthalic acid and terephthalic acid derivatives, and a diol component containing at least one compound selected from the group consisting of 2-methyl-1,3-propanediol and derivatives of 2-methyl-1,3-propanediol, and having a weight-average molecular weight as measured by gel permeation chromatography of at least 5000 and not more than 50000;
- a granulating step of dispersing the resulting resin composition in an aqueous medium to obtain a dispersion;
- and
- a solvent removal step of removing the organic solvent from the resulting dispersion.
Dependencies are inferred from the claim text.