US 7,534,542 B2
Binder resin for toner, method for producing the same, and toner for electrophotography using the resin
Takeshi Yoshida, Sodegaura (Japan); and Kazuya Sakata, Sodegaura (Japan)
Assigned to Mitsui Chemicals, Inc., Tokyo (Japan)
Appl. No. 10/572,647
PCT Filed Sep. 24, 2004, PCT No. PCT/JP2004/013893
§ 371(c)(1), (2), (4) Date Mar. 20, 2006,
PCT Pub. No. WO2005/028545, PCT Pub. Date Mar. 31, 2005.
Claims priority of application No. 2003-332582 (JP), filed on Sep. 24, 2003.
Prior Publication US 2007/0122731 A1, May 31, 2007
Int. Cl. G03G 5/00 (2006.01)
U.S. Cl. 430—137.15  [430/137.19; 430/109.2; 430/109.3; 526/273; 525/191; 525/208] 4 Claims
 
1. A method for producing the binder resin (A) for a toner comprising the following processes (I), (II) and (III) in this order:
Process (I): A process comprising melt-mixing a carboxyl group-containing vinyl resin (B) obtained by copolymerizing a vinyl monomer selected from styrene based compounds, acrylic esters, methacrylic esters, diesters of an unsaturated dibasic acid, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, N-substituted acrylamide, and N-substituted methacrylamide, and a vinyl monomer having a carboxyl group selected from acrylic acid methacrylic acid maleic anhydride, maleic acid, fumaric acid, cinnamic acid, and mono esters of an unsaturated dibasic acid and an epoxy group-containing vinyl resin (C) obtained by copolymerizing a vinyl monomer selected from styrene based comnounds, acrylic esters, methacryilc esters, diesters of an unsaturated dibasic acid, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, N-substituted acrylamide, and N-substituted methacrylamide, and a vinyl monomer having an epoxy group selected from glycidyl acrylate, β-methylglycidyl acrylate, glycidyl methacrylate, and β-methylglycidyl methacrylate at a temperature (TR) satisfying 120° C.≤TR≤230° C. in a twin screw extruder for the reaction;
Process (II): A process comprising introducing water into the twin screw extruder, and mixing water with the resin composition obtained in the Process (I) for 0.1 second to 5 under the conditions satisfying a pressure (PEX) of 1 MPa≤PEX≤2.7 MPa and a temperature (TM) of 120° C.≤TM≤230° C.; and
Process (III): A process comprising reducing the pressure inside the twin screw extruder for removing water and the volatile component.