Sharp Kabushiki Kaisha Corporation

Sharp Kabushiki Kaishi

Shigeaki Tasaka

Toshihisa Ishida

Tadashi Nakamura

Kiyofumi Morimoto

Naotaka Funayama

Nobuhiko Nakano

Satoshi Yamaue

Yoshinori Urata

Takahiro Horiuchi

Kazuya Maeda

Yoshiaki Takahashi

Kumiko Nakamura

Norio Tateishi

In the present method of manufacturing modified particles, a saturated vapor of a monomer B is produced in a condensing chamber, and then particles containing a monomer A, which differs from the monomer B and is polymerizable therewith, are introduced, along with an inert gas, into the condensing chamber through a particle intake. Then, a super-saturated vapor of the monomer B is created by reducing pressure using a pressurizing/depressurizing opening, thereby condensing the monomer B on the surface of the particles, and causing a polymerization reaction between the monomer A and the monomer B. With this method, spherical modified particles of uniform diameter, which include a polymer of the monomers A and B, can be obtained in a short time, by means of simple operations.

Method of manufacturing modified particles

The object of the invention is to provide a developer for electrophotography which may present stable charging properties and image density after a prolonged period of copying operations as well as have a long life. The object can be achieved by providing a developer for electrophotography, compounded of: a toner component; and a carrier component prepared from a ferrite powder mixture in total of 100 parts, consisting of 10 to 90 parts by weight of a ferrite powder having a specific surface range of 200 to 230 cm.sup.2 /g, and 10 to 90 parts by weight of a ferrite powder having a specific surface range of more than 230 to 300 cm.sup.2 /g.

Developer for electrophotography

A set of electrophotographic toners used for electrophotographic machines are disclosed which comprise an initial supply toner and a supplementary toner, both of which are composed of toner powder and additives adhering to the surface of the toner powder, wherein the weight ratio x of additives to toner powder in the initial supply toner is set to be greater than the weight ratio y of additives to toner powder in the supplementary toner.

Set of electrophotographic toners

Growing community of inventors

Nara, Japan

Shigeaki Tasaka