Patents by Inventor Shigefumi Kuramoto
Shigefumi Kuramoto has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Publication number: 20060167191Abstract: There is disclosed an additive for optical resins, wherein, even taking optical uses into consideration, the additive falls off little from such as binder resin layers or resin base materials and enables the exercise of uniform light diffusibility, without luminance unevenness, and high face luminescence. There is further disclosed an optical resin composition which comprises the above additive and a transparent resin and can display very excellent performances in optical properties such as no luminance unevenness and the face luminescence in the case of being employed for optical uses. The additive for optical resins is characterized by comprising organic-inorganic-composite particles having a structure including an organic polymer framework and a polysiloxane framework as essential frameworks. The optical resin composition is characterized by comprising the above additive for optical resins, according to the present invention, and a transparent resin.Type: ApplicationFiled: March 26, 2004Publication date: July 27, 2006Inventors: Yoshikuni Sasaki, Nobuyuki Ando, Tatsushi Hirauchi, Hayato Ikeda, Shigefumi Kuramoto
-
Patent number: 6331373Abstract: 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 SiO2 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.Type: GrantFiled: January 26, 1996Date of Patent: December 18, 2001Assignee: Nippon Shokubai Co., Ltd.Inventors: Shigefumi Kuramoto, Yasuhiro Sakai, Hayato Ikeda, Nobuyuki Ando
-
Patent number: 6091476Abstract: The present invention provides: a spacer for a liquid crystal display, which is difficult to aggregate when dispersed onto a substrate in a dry manner; a production process for the spacer; and a liquid crystal display including the spacer. The spacer has a mean particle diameter of 0.5 to 25 .mu.m, a coefficient of variation of 10% or less in particle diameter, and a fluidity of 30% or more, and preferably further has an electrification retention ratio of 40% or more at 5 minutes after corona electrification.Type: GrantFiled: August 12, 1997Date of Patent: July 18, 2000Assignee: Nippon Shokubai Co., Ltd.Inventors: Yasuhiro Sakai, Shinji Takasaki, Yoshikuni Sasaki, Shigefumi Kuramoto
-
Patent number: 5968694Abstract: The present invention provides photoconductive paints which have excellent dispersability and dispersion stability and which allow formation of coatings with high coating strength and excellent smoothness.The invention relates to photoconductive paint composed primarily of an inorganic photoconductive material and a binding resin formed on a conductive substrate, wherein the binding resin contains compound fine particles (A) and a resin (B) as defined below, in a solid weight ratio of compound fine particles (A)/resin (B) in the range of 0.5/9.5-4.0/6.0.The compound fine particles (A) have an organic polymer bound to surfaces of inorganic fine particles, and the resin (B) is a resin composition obtained by polymerizing an acrylic monomer mixture, the resin having an acid value of 2.0-12.0.Type: GrantFiled: April 28, 1998Date of Patent: October 19, 1999Assignees: Iwatsu Electro Co., Ltd., Nippon ShokubaiInventors: Hideki Sakai, Takafumi Hirano, Daijou Tomihisa, Shigefumi Kuramoto
-
Patent number: 5851605Abstract: In the adhesive spacers which are synthesized as by the impact method in a high-speed air current, resin particles formed solely of an adhesive layer are included in a large amount besides those of adhesive spacers. An adhesive particulate composition is obtained by adjusting these resin particles in terms of grain size. The adhesive particulate composition containing (a) adhesive particles having a thermoplastic resin-containing layer cover at least part of the surfaces of the core particles having an average particle diameter in the range of 1 to 20 .mu.m and a coefficient of variation of not more than 10% and (b) adhesive layer particles formed of the thermoplastic resin and having a ratio of the number of (b) the adhesive layer particles to that of (a) the adhesive particles of not more than 30%, adhesive spacers for a liquid crystal display panel formed of the composition, and the liquid crystal display panel using the spacers are disclosed.Type: GrantFiled: December 24, 1996Date of Patent: December 22, 1998Assignees: Matsushita Electric Industrial Co., Ltd., Nippon Shokubai Co., Ltd.Inventors: Shinji Hisamitsu, Teruhisa Ishihara, Katsuya Tamaki, Shigefumi Kuramoto, Yasuhiro Sakai, Shinji Takasaki
-
Patent number: 5683501Abstract: Compound fine particles include inorganic fine particles and an organic polymer bound to surfaces of the inorganic fine particles, and have an average particle diameter of 5 to 200 nm and a particle diameter variation coefficient of 50% or less. The compound fine particles are obtainable by hydrolyzing and condensing an organic polymer, wherein the organic polymer has, per molecule, at least one polysiloxane group containing at least one Si--OR.sup.1 group, wherein R.sup.1 denotes a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubstituted or substituted acyl group. A compound fine particle dispersion includes the compound fine particles and a dispersion medium. A composition for forming a film includes this dispersion.Type: GrantFiled: November 4, 1994Date of Patent: November 4, 1997Assignee: Nippon Shokubai Co., Ltd.Inventors: Daijo Tomihisa, Shigefumi Kuramoto, Satoshi Ishida, Tadahiro Yoneda, Masaya Yoshida, Ichiro Namura
-
Patent number: 5670257Abstract: Organic-inorganic composite particles which include a (meth)acrylic resin framework and a polysiloxane framework having in its molecule an organosilicon containing a silicon atom directly and chemically combined with at least one carbon atom of the (meth)acrylic resin framework, and also contain 25 wt % or more of SiO.sub.2 which constitutes the polysiloxane framework and have a mean particle diameter of .gtoreq.0.5 .mu.m. The particles have the mechanical resilience necessary to maintain a constant gap distance between a pair of members to be arranged with the correct gap distance between them, and the hardness and fracture strength necessary to maintain the gap constant with smaller numbers; and also do not readily cause physical damage to the members. The composite particles can be employed as spacers 8 for a liquid crystal display as they stand or with an adhesive layer formed on the surface.Type: GrantFiled: December 7, 1995Date of Patent: September 23, 1997Assignee: Nippon Shokubai Co., Ltd.Inventors: Yasuhiro Sakai, Tadahiro Yoneda, Shigefumi Kuramoto
-
Patent number: 5580619Abstract: Organic-inorganic composite particles which include a (meth)acrylic resin framework and a polysiloxane framework having in its molecule an organosilicon containing a silicon atom directly and chemically combined with at least one carbon atom of the (meth)acrylic resin framework, and also contain 25 wt % or more of SiO.sub.2 which constitutes the polysiloxane framework and have a mean particle diameter of .gtoreq.0.5 .mu.m. The particles have the mechanical resilience necessary to maintain a constant gap distance between a pair of members to be arranged with the correct gap distance between them, and the hardness and fracture strength necessary to maintain the gap constant with smaller numbers; and also do not readily cause physical damage to the members. The composite particles can be employed as spacers 8 for a liquid crystal display as they stand or with an adhesive layer formed on the surface.Type: GrantFiled: December 7, 1995Date of Patent: December 3, 1996Assignee: Nippon Shokubai Co., Ltd.Inventors: Yasuhiro Sakai, Tudahiro Yoneda, Shigefumi Kuramoto
-
Patent number: 5503932Abstract: Organic-inorganic composite particles which include a (meth)acrylic resin framework and a polysiloxane framework having in its molecule an organosilicon containing a silicon atom directly and chemically combined with at least one carbon atom of the (meth)acrylic resin framework, and also contain 25 wt % or more of SiO.sub.2 which constitutes the polysiloxane framework and have a mean particle diameter of .gtoreq.0.5 .mu.m. The particles have the mechanical resilience necessary to maintain a constant gap distance between a pair of members to be arranged with the correct gap distance between them, and the hardness and fracture strength necessary to maintain the gap constant with smaller numbers; and also do not readily cause physical damage to the members. The composite particles can be employed as spacers 8 for a liquid crystal display as they stand or, with an adhesive layer formed on the surface.Type: GrantFiled: November 15, 1994Date of Patent: April 2, 1996Assignee: Nippon Shokubai Co., Ltd.Inventors: Yasuhiro Sakai, Tadahiro Yoneda, Shigefumi Kuramoto