# US 7,745,085 B2 · Toner for developing electrostatic latent image and method of manufacturing same, electrostatic latent image developer, cartridge, and image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,745,085 B2 - Document ID: US7745085B2 - Status: Granted - Kind: B2 - Application number: 11/727,495 - Filed: 2007-03-27 - Published: 2008-01-31 - Granted: 2010-06-29 - Earliest claimed: 2006-07-28 - Assignees: Fuji Xerox Co., Ltd. - Inventors: Takao Ishiyama; Takashi Inukai; Akitsugu Seto; Tomohito Nakajima - Web page: https://patentgrep.com/patent/US7745085B2 ## CPC - G03G 9/08755: {Polyesters} - G03G 9/0804: {whereby the components are brought together in a liquid dispersing medium} - G03G 9/08793: {Crosslinked polymers} - G03G 9/08795: {characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants} - G03G 9/08797: {characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature} - G03G 2215/2045: Variable fixing speed - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A toner for developing an electrostatic latent image that includes a crystalline polyester resin and a release agent, wherein structures in which the crystalline polyester resin contacts the release agent exist in a ruthenium-stained cross section of the toner, and if the cross-sectional area of these structures is labeled A, the cross-sectional area of lone portions of the release agent is labeled B, and the cross-sectional area of lone portions of the crystalline polyester resin is labeled C, then 40≦100×A/(A+B+C)≦70, 10≦100×B/(A+B+C)≦30, and 20≦100×C/(A+B+C)≦30. ## Claims ### Claim 1 A toner for developing an electrostatic latent image, comprising a crystalline polyester resin, a non-crystalline polyester resin and a release agent, wherein: an acid value of the crystalline polyester resin is within a range from 5 to 10 mgKOH/g; an acid value of the non-crystalline polyester resin is within a range from 10 to 15 mgKOH/g; a melting temperature of the crystalline polyester resin determined in accordance with ASTM D3418-8 is within a range from 50 to 120° C.; a weight average molecular weight (Mw) of the crystalline polyester resin is within a range from 10,000 to 25,000; a glass transition temperature (Tg) of the non-crystalline polyester resin determined in accordance with ASTM D3418-8 is 50° C. or higher; a weight average molecular weight (Mw) of the non-crystalline polyester resin is within a range from 20,000 to 50,000; a weight ratio between the crystalline polyester resin and the non-crystalline polyester resin is within a range from 5/95 to 40/60; and structures in which the crystalline polyester resin contacts the release agent exist in a ruthenium-stained cross section of the toner, and if a cross-sectional area of the structures is labeled A, a cross-sectional area of lone portions of the release agent is labeled B, and a cross-sectional area of lone portions of the crystalline polyester resin is labeled C, then 40≦100×A/(A+B+C)≦70, 10≦100×B/(A+B+C)≦30, and 20≦100×C/(A+B+C)≦30. ### Claim 2 (depends on 1) The toner for developing an electrostatic latent image according to claim 1, wherein a softening temperature of the non-crystalline polyester resin is within a range from 60 to 90° C. ### Claim 3 (depends on 1) The toner for developing an electrostatic latent image according to claim 1, wherein a quantity of the release agent relative to a total weight of the toner is within a range from 0.5 to 50% by weight. ### Claim 4 (depends on 1) The toner for developing an electrostatic latent image according to claim 1, wherein a volume average particle size distribution index GSDv of the toner is no greater than 1.30. ### Claim 5 (depends on 1) The toner for developing an electrostatic latent image according to claim 1, wherein a toner shape factor SF1 satisfies 110≦SF1≦140. ### Claim 6 A method of manufacturing a toner for developing an electrostatic latent image, the method comprising: adding a neutralizing agent and a water-based medium to a resin solution prepared by dissolving a non-crystalline polyester resin and a crystalline polyester resin in an organic solvent, thereby causing a phase inversion and generating an alkaline material; subsequently forming O/W emulsified resin particles; and aggregating and fusing a resin particle dispersion obtained by removing the organic solvent from the emulsified resin particles and a release agent particle dispersion to obtain a toner that comprises the crystalline polyester resin, the non-crystalline polyester resin and the release agent, wherein: an acid value of the crystalline polyester resin is within a range from 5 to 10 mgKOH/g; an acid value of the non-crystalline polyester resin is within a range from 10 to 15 mgKOH/g; a melting temperature of the crystalline polyester resin determined in accordance with ASTM D3418-8 is within a range from 50 to 120° C.; a weight average molecular weight (Mw) of the crystalline polyester resin is within a range from 10,000 to 25,000; a glass transition temperature (Tg) of the non-crystalline polyester resin determined in accordance with ASTM D3418-8 is 50° C. or higher; a weight average molecular weight (Mw) of the non-crystalline polyester resin is within a range from 20,000 to 50,000; a weight ratio between the crystalline polyester resin and the non-crystalline polyester resin is within a range from 5/95 to 40/60; and structures in which the crystalline polyester resin contacts the release agent exist in a ruthenium-stained cross section of the toner, and if a cross-sectional area of these structures is labeled A, a cross-sectional area of lone portions of the release agent is labeled B, and a cross-sectional area of lone portions of the crystalline polyester resin is labeled C, then 40≦100×A/(A+B+C)≦70, 10≦100×B/(A+B+C)≦30, and 20≦100×C/(A+B+C)≦30. ### Claim 7 (depends on 1) An electrostatic latent image developer, comprising a carrier with a particle size distribution of 1.3 or lower, and the toner for developing an electrostatic latent image according to claim 1. ### Claim 8 A toner cartridge comprising a toner for developing an electrostatic latent image, the toner comprising a crystalline polyester resin, a non-crystalline polyester resin and a release agent, wherein: an acid value of the crystalline polyester resin is within a range from 5 to 10 mgKOH/g; an acid value of the non-crystalline polyester resin is within a range from 10 to 15 mgKOH/g; a melting temperature of the crystalline polyester resin determined in accordance with ASTM D3418-8 is within a range from 50 to 120° C.; a weight average molecular weight (Mw) of the crystalline polyester resin is within a range from 10,000 to 25,000; a glass transition temperature (Tg) of the non-crystalline polyester resin determined in accordance with ASTM D3418-8 is 50° C. or higher; a weight average molecular weight (Mw) of the non-crystalline polyester resin is within a range from 20,000 to 50,000; a weight ratio between the crystalline polyester resin and the non-crystalline polyester resin is within a range from 5/95 to 40/60; and structures in which the crystalline polyester resin contacts the release agent exist in a ruthenium-stained cross section of the toner, and if a cross-sectional area of these structures is labeled A, a cross-sectional area of lone portions of the release agent is labeled B, and a cross-sectional area of lone portions of the crystalline polyester resin is labeled C, then 40≦100×A/(A+B+C)≦70, 10≦100×B/(A+B+C)≦30, and 20≦100×C/(A+B+C)≦30. ### Claim 9 (depends on 1) A removable cartridge, comprising a latent image forming unit that forms a latent image on a latent image holding member, a developing unit that develops the latent image using an electrostatic latent image developer, and a transfer unit that transfers the developed image to a transfer target, wherein the electrostatic latent image developer comprises the toner for developing an electrostatic latent image according to claim 1. ### Claim 10 (depends on 1) An image forming apparatus, comprising a latent image forming unit that forms a latent image on a latent image holding member, a developing unit that develops the latent image using an electrostatic latent image developer, a transfer unit that transfers the developed image to a transfer target, and a fixing unit that heat fixes the image on the transfer target, wherein the electrostatic latent image developer comprises the toner for developing an electrostatic latent image according to claim 1, and a contact time between an image and a fixing member within the fixing unit is at least 0.01 seconds but no longer than 0.1 seconds.