Abstract: An epoxy group-containing acrylic resin for a powder coating is prepared by suspension polymerization at a temperature of at least 80° C. and a pressure of at least 2 kg/cm2 with a vinyl monomer mixture comprising from 10-60% by weight of epoxy group-containing vinyl monomers, from 10-60% by weight of alkyl (meth)acrylate(s), and other vinyl monomer(s). The epoxy group-containing acrylic resin particles possess the following characteristics: i) a weight average molecular weight of from 3000-20,000; ii) an epoxy equivalent of from 350-1200 g/eq; iii) 1000 ppm or less of volatile components; iv) a mean particle diameter of from 80-800 &mgr;m; v) at least 95% by weight of the particles having a long diameter R:short diameter r ratio within the parameters 1<R/r<1.2; and vi) 5% by weight or less of the particles having a long diameter R of less than 62 &mgr;m and 5% by weight or less of particles having a short diameter r of more than 1000 &mgr;m.

Abstract: An epoxy group-containing acrylic resin for a powder coating composition is here disclosed which is a copolymer, having a weight-average molecular weight of 3000 to 20000, of a vinyl monomer mixture comprising 10 to 60% by weight of alkyl ester(s) of (meth)acrylic acid, 10 to 60% by weight of epoxy group-containing vinyl monomer(s) and other vinyl monomer(s), said epoxy group-containing acrylic resin having a mean particle diameter in the range of 80 to 800 &mgr;m, including 95% by weight or more of particles satisfying the relation of 1≦R/r≦1.2 wherein R is a long diameter and r is a short diameter of each particle, and including 1000 ppm or less of volatile components, the amount of the particles having long diameters R of less than 62 &mgr;m being 5% by weight or less, that of the particles having short diameters r of more than 1000 &mgr;m being 5% by weight or less.

Abstract: An epoxy group-containing acrylic resin for a powder coating composition is a copolymer, having a weight-average molecular weight of 3000 to 20000, of a vinyl monomer mixture comprising 10 to 60% by weight of alkyl ester(s) of (meth)acrylic acid, 10 to 60% by weight of epoxy group-containing vinyl monomer(s) and other vinyl monomer(s), said epoxy group-containing acrylic resin having a mean particle diameter in the range of 80 to 800 &mgr;m, including 95% by weight or more of particles satisfying the relation of 1≦R/r≦1.2 wherein R is a long diameter and r is a short diameter of each particle, and including 1000 ppm or less of volatile components, the amount of the particles having long diameters R of less than 62 &mgr;m being 5% by weight or less, that of the particles having short diameters r of more than 1000 &mgr;m being 5% by weight or less.

Abstract: Toner binder resins with low odor and excellent charging stability as toners, containing styrene-acrylic copolymers or mixtures thereof, wherein the total content of volatile components is no greater than about 1,500 ppm, the content of volatile components with benzene rings is no greater than about 1,400 ppm, and the content of volatile components with benzene rings and boiling point of below about 200° C. is no greater than about 500 ppm.

Abstract: A binder resin for toners which comprises a styrene-acrylic resin comprising a high molecular weight polymer component and a low molecular weight polymer component, wherein, in terms of the molecular weight distribution as measured by gel permeation chromatography, the high molecular weight polymer component has a first peak in the region of molecular weight 5.times.10.sup.4 to 8.times.10.sup.5 and at least 2 peaks and/or shoulders at the high molecular weight side above the molecular weight of the first peak, as well as a toner containing the resin.

Abstract: A toner resin, comprising a styrene component, an acrylic acid ester component or methacrylic acid ester component or both, and a divinyl monomer component, the resin having a glass transition temperature of 50.degree. to 68.degree. C., a value of tan .delta., which is the ratio of the dynamic loss to the dynamic elastic modulus, of 0.3 to 0.7 as measured at 200.degree. C., a gel fraction of 55 to 83%, and a softening point at which the resin has a melting viscosity of 100,000 poises is 200.degree. to 410.degree. C. A toner having an excellent fixing property, non-offsetting property, and blocking resistance, and able to be used with a high-temperature high-speed copying machine is formed from this toner resin.

Abstract: A binder resin for high image quality toners used in copying machines and printers by electrophotography which are excellent in anti-offset property, fixing property, blocking resistance, and image characteristics obtained by controlling the molecular weight, blend ratio, acid value, and ratio of a high molecular weight polymer and a low molecular weight polymer of the binder resin to specific values.

Abstract: A resin composition for toners, composed essentially of a suspension polymerizate of:(a) 5 to 40% by weight per total polymer of a polyester comprising at least one aromatic diol component an at least one aliphatic diol component, and having a weight average molecular weight of 3,000 to 30,000, an acid value of 0.5 to 10 mgKOH/g, and an OH value of 10 to 60 mgKOH/g;(b) 60 to 95% by weight per total polymer of a vinyl monomer; and(c) 0.1 to 1.0% by weight per total polymer of a divinyl monomer,wherein said suspension polymerizate hasa glass transition temperature of 40.degree. to 70.degree. C.,an acid value of 0.1 to 10 mgKOH/g, anda softening temperature of 100.degree. to 160.degree. C.

Abstract: A toner resin composition comprising 5 to 40% by weight of a polyester (A) having a weight average molecular weight of 3,000 to 20,000 and 50 to 95% by weight of a styrene-acrylic copolymer (B). The styrene-acrylic copolymer (B) is comprised of 10 to 25% by weight of a high molecular weight polymer (B1) having a weight average molecular weight of 500,000 to 1,100,000 and 75 to 90% by weight of a low molecular weight polymer (B2) having a weight average molecular weight of 5,000 to 100,000. The high molecular weight polymer (B1) is comprised of a styrene component (b-1) and an acrylic ester and/or methacrylic ester component (b-2). The low molecular weight polymer (B2) is comprised of a styrene component (b-1), an acrylic ester and/or methacrylic ester component (b-2), 0.3 to 3 parts by weight, per 100 parts of the total weight of said component (b-1) and component (b-2), of an .alpha.-methyl styrene dimer (b-3) and 0.

Abstract: A binder for toner comprising a styrene/(meth)acrylate copolymer obtained by polymerizing polymerizable vinyl monomers comprising styrene and/or its derivative and a (meth)acrylate by suspension polymerization of 0.001-3 wt. %, based on the total weight of the monomers used, of at least one polyvinyl alcohol having a degree of saponification of 75-98% and 1.0-10 wt. %, based on the total weight of the monomers used, of at least one azo initiator. According to the present invention, there is provided a binder for a toner which produces copied images having excellent stability of image quality (life) even after a large number of times of copying.

Abstract: A process for producing a toner resin by a two-step suspension polymerization process, which entails preparing a polymer of high molecular weight having a weight average molecular weight of greater than about 350,000 from at least one monomer having a polymerizable vinyl group using a compound having at least three t-butyl peroxide groups in one molecule, as a polymerization initiator, and then preparing a low molecular weight polymer in the presence of the high molecular weight polymer. A toner having an excellent fixing property and offset resistance can be obtained from the above resin.

Abstract: A process for producing a toner resin by a two-step suspension polymerization process, which entails preparing a polymer of high molecular weight having a weight average molecular weight of greater than about 350,000 from at least one monomer having a polymerizable vinyl group using a compound having at least three t-butyl peroxide groups in one molecule, as a polymerization initiator, and then preparing a low molecular weight polymer in the presence of the high molecular weight polymer. A toner having an excellent fixing property and offset resistance can be obtained from the above resin.

Abstract: A resin for toner containing fine particles with a particle size passing through a 200 mesh sieve of not greater than 10% by weight.