Abstract: The invention is [1] a resin composition comprising a resin obtained by polymerizing cyclopentadiene or the like and a specific styrene resin, [2] a resin composition comprising (a) a polystyrene-type polymer component and (b) a specific petroleum resin-based polymer component, and [3] a toner binder resin for development of an electrostatically charged image comprising (A) a terpene resin or the like and (B) a styrene resin and/or a polyester resin. Further, it is a toner binder resin for development of an electrostatically charged image containing these resin compositions as a main component, and a toner for development of an electrostatically charged image comprising the toner binder resin and a coloring material.

Abstract: The invention is [1] a resin composition comprising a resin obtained by polymerizing cyclopentadiene or the like and a specific styrene resin, [2] a resin composition comprising (a) a polystyrene-type polymer component and (b) a specific petroleum resin-based polymer component, and [3] a toner binder resin for development of an electrostatically charged image comprising (A) a terpene resin or the like and (B) a styrene resin and/or a polyester resin. Further, it is a toner binder resin for development of an electrostatically charged image containing these resin compositions as a main component, and a toner for development of an electrostatically charged image comprising the toner binder resin and a coloring material.

Abstract: Disclosed are a carrier for electrophotography, a method for producing the same carrier, and a developing agent using the same. The carrier includes a carrier core material with magnetism and a high-molecular-weight polyethylene resin that coats the surface of the carrier core material, wherein the surface of the high-molecular-weight polyethylene resin coating the surface of the carrier core material is coated with a resin layer having an ability to control an electric charge and a thickness of 0.01-2 &mgr;m or with a particle layer having an ability to control an electric charge and a thickness of 0.01-2 &mgr;m. The carrier for electrophotography and the developing agent using the same allow free control of its electrification polarity and free adjustment of the amount of electrification, taking advantage of excellent properties of the carrier having a polyolefin-based resin coat.

Abstract: The present invention provides a polyolefinic resin-coated carrier having a rough surface and containing a core material in a quantity of 90 or more % by weight. Said resin-coated layer may contain fine particles having a charge-controlling function and/or electrically conductive fine particles as additives.

Abstract: The present invention provides a carrier of a two component developer for developing electrostatic latent images comprising;a carrier core material comprising a magnetic particle,an irregular surface-coating layer formed by coating the carrier core material with polyolefinic resin, followed by heat treatment.

Abstract: The present invention provides fine particles comprising core particles and polyolefinic resin layers for composing an electrostatic latent image developer, characterized in that the polyolefinic resin layers are formed by polymerizing olefinic monomers on surfaces of the core particles.

Abstract: The present invention provides a polyolefinic resin-coated carrier having a rough surface and containing a core material in a quantity of 90 or more % by weight. Said resin-coated layer may contain fine particles having a charge-controlling function and/or electrically conductive fine particles as additives.