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 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.

Abstract: A process for the preparation of a toner polymer which comprises the steps of carrying out suspension polymerization of a monomer having a polymerizable vinyl group in the presence of polyvinyl alcohol as a dispersant, and then conducting oxidative decomposition of polyvinyl alcohol anchored to polymer particles obtained by suspension polymerization.