The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 18, 2001
Filed:
Jan. 26, 1996
Shigefumi Kuramoto, Osaka, JP;
Yasuhiro Sakai, Osaka, JP;
Hayato Ikeda, Osaka, JP;
Nobuyuki Ando, Nara, JP;
Nippon Shokubai Co., Ltd., Osaka-fu, JP;
Abstract
An electrostatic image developer which has an improved charge retaining ratio is disclosed. The developer comprises toner particles comprising (a) a binding resin and (b) a coloring agent and having a mean particle diameter of not more than 25 &mgr;m, and (c) organic-inorganic composite particles attached or fixed to the surface or the proximity of surface of said toner particles. The composite particle contains an organic polymer framework and a polysiloxane framework, the polysiloxane framework having in the molecule thereof an organosilicon which has a silicon atom to which at least one carbon atom in said organic polymer framework combined directly, the organic-inorganic composite particles having SiO,as a component of said polysiloxane framework at a content in the range of 10 to 90% by weight. The composite particles have a mean particle diameter in the range of 0.01 to 5 &mgr;m. The mixing ratio of (b) the coloring agent to (a) the binding resin in the toner particles in 20 to 2 parts by weight of (b) to 80 to 98 parts by weight of (a), as the total amount of (a) and (b) is 100 parts. The mixing ratio of the organic-inorganic composite particles to the toner particles is 0.01 to 20 parts by weight of the composite particles to 100 parts by weight of the toner particles.