# US 2011/0217644 A1 · Toner, developer using the toner, method for preparing the toner, and image forming method and apparatus using the toner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2011/0217644 A1 - Document ID: US20110217644A1 - Status: Published application - Kind: A1 - Application number: 13/040,019 - Filed: 2011-03-03 - Published: 2011-09-08 - Earliest claimed: 2010-03-04 - Assignees: Ricoh Company, Ltd. - Inventors: Atsushi Yamamoto; Tsuyoshi Nozaki; Chiyoshi Nozaki - Web page: https://patentgrep.com/patent/US20110217644A1 ## CPC - G03G 9/08: with toner particles - G03G 9/0804: {whereby the components are brought together in a liquid dispersing medium} - G03G 9/0806: {whereby chemical synthesis of at least one of the toner components takes place} - G03G 9/08711: {with esters of acrylic or methacrylic acid} - G03G 9/08755: {Polyesters} - G03G 9/08791: {characterised by the presence of specified groups or side chains} - 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 13/20: Fixing, e.g. by using heat - G03G 15/08: using a solid developer, e.g. powder developer - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A method for preparing a toner including toner particles is provided. The toner preparation method includes preparing a toner component liquid including at least a binder resin, a colorant and an organic solvent; mixing a resin A having a solubility of less than 2.0 g/100 g in water having a pH of 3.0 at 25° C. while having a solubility of not less than 2.0 g/100 g, a basic material, and water to prepare an aqueous phase liquid, in which the resin A is dissolved; forming droplets of the toner component liquid in the aqueous phase liquid; and removing the organic solvent from the droplets of the toner component liquid to prepare the toner particles. ## Claims ### Claim 1 A method for preparing a toner including toner particles, comprising: preparing a toner component liquid including at least a binder resin, a colorant and an organic solvent; mixing at least a resin A having a solubility of less than 2.0 g/100 g in water having a pH of 3.0 at 25° C. while having a solubility of not less than 2.0 g/100 g in water having a pH of 10.0 at 25° C., a basic material, and water to prepare an aqueous phase liquid, in which the resin A is dissolved; forming droplets of the toner component liquid in the aqueous phase liquid; and removing the organic solvent from the droplets of the toner component liquid to prepare the toner particles. ### Claim 2 (depends on 1) The method according to claim 1, wherein the resin A includes a first unit obtained from a monomer 1 having the following formula (1) and a second unit obtained from a monomer 2 having the following formula (2): wherein R3 represents a hydrogen atom or a methyl group, wherein the first unit is included in the resin A in an amount of from 20 to 80% by weight, and the second unit is included in the resin A in an amount of from 15 to 65% by weight. ### Claim 3 (depends on 2) The method according to claim 2, wherein the resin A further includes a third unit obtained from a monomer 3 having the following formula (3): wherein R1 represents a hydrogen atom or a methyl group, and R2 represents a hydrocarbon group having 1 to 22 carbon atoms. ### Claim 4 (depends on 2) The method according to claim 2, wherein the resin A further includes a third unit obtained from a monomer 4 having the following formula (4): wherein R4 represents a hydrogen atom or a methyl group, X represents a divalent hydrocarbon group, and M represents a hydrogen atom, a sodium atom, a potassium atom or a hydrocarbon group having 1 to 4 carbon atoms. ### Claim 5 (depends on 2) The method according to claim 2, wherein the aqueous phase liquid preparation step includes: reacting a monomer composition including the monomers 1 and 2 in an aqueous medium including a surfactant using a water soluble radical generating agent to prepare a dispersion of the resin A having a solubility of less than 2.0 g/100 g in water having a pH of 3.0 at 25° C. while having a solubility of not less than 2.0 g/100 g in water having a pH of 10.0 at 25° C.; and mixing at least the dispersion of the resin A, a basic material, and water to prepare an aqueous phase liquid, in which the resin A is dissolved. ### Claim 6 (depends on 2) The method according to claim 2, wherein the aqueous phase liquid preparation step includes: reacting a monomer composition including the monomers 1 and 2 dissolved in a solvent, in which a radical generating agent is dissolved, to prepare a resin A having a solubility of less than 2.0 g/100 g in water having a pH of 3.0 at 25° C. while having a solubility of not less than 2.0 g/100 g in water having a pH of 10.0 at 25° C.; and mixing at least the resin A, a basic material, and water to prepare an aqueous phase liquid, in which the resin A is dissolved. ### Claim 7 (depends on 1) The method according to claim 1, wherein the binder resin has a polyester unit. ### Claim 8 (depends on 7) The method according to claim 7, wherein the binder resin having a polyester unit has an acid value of from 2 to 24 mgKOH/g. ### Claim 9 (depends on 7) The method according to claim 7, wherein the binder resin having a polyester unit is a polyester resin. ### Claim 10 (depends on 1) The method according to claim 1, wherein the toner component liquid further includes a resin having an isocyanate group at an end thereof, which is dissolved in the organic solvent. ### Claim 11 (depends on 10) The method according to claim 10, wherein the resin having an isocyanate group at an end thereof has a polyester unit. ### Claim 12 (depends on 10) The method according to claim 10, wherein the toner component liquid further includes an amine compound having a di- or more-valent amino group reactive with the isocyanate group of the resin. ### Claim 13 (depends on 1) The method according to claim 1, wherein the basic material is a compound having a cation selected from the group consisting of alkali metal cations, and alkali earth metal cations, and an anion selected from the group consisting of OH−, COO2−, HCOO−, PO43−, HPO42−, and H2PO4−. ### Claim 14 (depends on 1) A toner comprising toner particles including a binder resin and a colorant, wherein the toner is prepared by the method according to claim 1. ### Claim 15 (depends on 14) A developer comprising the toner according to claim 14 and a carrier. ### Claim 16 (depends on 14) An image forming apparatus comprising: an image bearing member; a charger to charge a surface of the image bearing member; an irradiator to irradiate the charged image bearing member with light based on image data to form an electrostatic latent image on the surface of the image bearing member; a developing device to develop the electrostatic latent image with a developer including the toner according to claim 14 to form a toner image on the image bearing member; a transferring device to transfer the toner image onto a recording material; and a fixing device to fix the toner image on the recording material. ### Claim 17 (depends on 16) The image forming apparatus according to claim 16, further comprising: a toner supplying device to supply the toner from a toner container to the developing device. ### Claim 18 (depends on 14) An image forming method comprising: charging a surface of an image bearing member; irradiating the charged image bearing member with light based on image data to form an electrostatic latent image on the surface of the image bearing member; developing the electrostatic latent image with a developer including the toner according to claim 14 to form a toner image on the image bearing member; transferring the toner image onto a recording material; and fixing the toner image on the recording material. ### Claim 19 (depends on 18) The image forming method according to claim 18, further comprising: supplying the toner from a toner container to the developer.