Patents by Inventor Chikashi Kawashima
Chikashi Kawashima 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).
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Patent number: 6025436Abstract: The invention provides a thermoplastic fluorine-containing resin composition intended to be passed between at least two rollers of a calender to be thinned into a sheet or film. This composition includes: 100 parts by weight of a mixture containing 10-90 wt % of a fluorine-containing elastomeric polymer having a glass transition temperature below room temperature and 90-10 wt % of a fluorine-containing crystalline resin having a melting point not higher than 300.degree. C.; and 0.05-2.0 parts by weight of an agent for releasing the composition from the at least two rollers. The composition has a good melt characteristic and a good elasticity for calendering of the composition, and a good releasibility from a calender roller in calendering of the composition.Type: GrantFiled: May 23, 1997Date of Patent: February 15, 2000Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Katunori Kawamura, Seiiti Minegishi
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Patent number: 5902859Abstract: The invention relates to an elastic fluorohydrocarbon resin. This resin is obtained by graft copolymerization of a first segment which is one of fluorine-containing elastomeric and crystalline polymers with a second segment which is the other of these polymers. The first segment is prepared by copolymerizing at least one first unsaturated monomer that has peroxy bond with at least one second fluorine-containing monomer. When the first monomer is dissolved in a first solvent prior to the copolymerization, the copolymerization can be safely conducted with higher yield. This first solvent is selected from a carboxylic ester of t-butanol, methylene chloride, 1,1,1-trichloroethane, and first, second, third and fourth compounds which are respectively represented by R.sup.1 COOR.sup.2, C.sub.2 H.sub.x Cl.sub.y F.sub.z, C.sub.3 H.sub.x Cl.sub.y F.sub.z, and C.sub.4 H.sub.x Cl.sub.y F.sub.z.Type: GrantFiled: June 23, 1997Date of Patent: May 11, 1999Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Akira Ishihara, Katunori Kawamura, Seiiti Minegishi
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Patent number: 5898051Abstract: The invention provides a fluorine-containing resin blend. This resin blend includes 100 parts by weight of a first resin and 1-50 parts by weight of a second resin. The first resin is one of an elastic fluorohydrocarbon resin and a vinylidene fluoride based resin. The second resin is a graft copolymer prepared by graft copolymerization of a rubber-like polymer with a first monomer and an optional second monomer. The first monomer is at least one of an acrylic ester and a methacrylic acid ester. The optional second monomer is at least one copolymerizable monomer other than the first monomer. When the elastic fluorohydrocarbon resin is used as the first resin, the resin blend is improved in extensibility upon molding in a melted condition and lowered in modulus of elasticity under a condition that the resin blend is strained by up to 20%, without impairing the elastic fluorohydrocarbon in its heat resistance, low-temperature characteristics and the like.Type: GrantFiled: January 31, 1996Date of Patent: April 27, 1999Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Fumiyoshi Yoshikawa, Seiiti Minegishi
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Patent number: 5863657Abstract: An adhesive for bonding together a first substrate made of vinylidene fluoride resin and a second substrate comprises an elastic fluorohydrocarbon resin, a polyisocyanate, and an organic solvent. This elastic fluorohydrocarbon resin is obtained by graft copolymerization of a fluorine-containing copolymer with a vinylidene fluoride monomer. This copolymer is prepared by copolymerizing at least one first fluorine-containing monomer with at least one unsaturated monomer that has peroxy bond. The adhesive itself is superior in durability, and bond strength between the first and second substrates is also superior.Type: GrantFiled: December 27, 1995Date of Patent: January 26, 1999Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Katunori Kawamura
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Patent number: 5696215Abstract: The invention relates to an elastic fluorohydrocarbon resin. This resin is obtained by graft copolymerization of a first segment which is one of fluorine-containing elastomeric and crystalline polymers with a second segment which is the other of these polymers. The first segment is prepared by copolymerizing at least one first unsaturated monomer that has peroxy bond with at least one second fluorine-containing monomer. When the first monomer is dissolved in a first solvent prior to the copolymerization, the copolymerization can be safely conducted with higher yield. This first solvent is selected from a carboxylic ester of t-butanol, methylene chloride, 1,1,1-trichloroethane, and first, second, third and fourth compounds which are respectively represented by R.sup.1 COOR.sup.2, C.sub.2 H.sub.x Cl.sub.y F.sub.z, C.sub.3 H.sub.x Cl.sub.y F.sub.z, and C.sub.4 H.sub.x Cl.sub.y F.sub.z.Type: GrantFiled: February 28, 1996Date of Patent: December 9, 1997Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Akira Ishihara, Katunori Kawamura, Seiiti Minegishi
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Patent number: 5441782Abstract: A plastic laminate having an apliphatic polyamide resin surface layer and a fluororesin surface layer is produced by using an intermediate layer formed of a blend of an aliphatic polyamide resin with a fluorine-containing graft copolymer, which is obtained by graft polymerization of a suitable monomer such as vinylidene fluoride, or a mixture of monomers, with an elastomeric copolymer of at least two principal monomers including at least one fluorine-containing monomer, e.g. vinyliden fluoride and chlorotrifluoroethylene, and an unsaturated peroxy compound. The fluorine-containing graft copolymer is a soft, flexible resin and is well compatible with aliphatic polyamide resins and also with various fluororesins. The fluororesin surface layer uses, for example, polyvinylidene fluoride, a vinyliden fluoride based copolymer or the fluorine-containing graft copolymer. The lamination can be accomplished by simply welding the two surface layers to the intermediate layer.Type: GrantFiled: July 13, 1992Date of Patent: August 15, 1995Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Seiichi Yoshida, Sunao Koga, Satoshi Nakahata, Fumiyoshi Yoshikawa
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Patent number: 5294669Abstract: A thermoplastic resin composition, which is flexible and can easily be extruded, is obtained by blending (A) 100 parts by weight of a thermoplastic urethane elastomer with (B) 1-100 parts by weight of a thermoplastic graft copolymer obtained by graft polymerization of vinylidene fluoride with an elastomeric copolymer of at least two principal monomers including at least one fluorine-containing compound, e.g. vinylidene fluoride and chlorotrifluoroethylene, and an unsaturated peroxy compound. Compared with the urethane elastomer (A) itself, this resin composition is better in extrudability, lower in kinetic friction coefficient, weaker in surface tackiness of molded products and higher in resistance to heat aging.Type: GrantFiled: June 19, 1992Date of Patent: March 15, 1994Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Sunao Koga, Katunori Kawamura
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Patent number: 4749610Abstract: A glass fiber reinforced flexible composite material is obtained by dispersing or embedding glass fiber in a fluororesin, which is a graft copolymer obtained by grafting a crystalline fluoro-polymer to an elastomeric fluoro-polymer. For example, the graft copolymer is obtained by graft polymerization of vinylidene fluoride with an elastomeric copolymer of vinylidene fluoride, chlorotrifluoroethylene and an unsaturated peroxy compound. The composite material possesses the physical and chemical properties characteristic of fluororesins and is flexible and easily melt processable. Sheets of this composite material using a glass fiber cloth have a soft feel and can easily be joined by high-frequency welding.Type: GrantFiled: February 17, 1987Date of Patent: June 7, 1988Assignee: Central Glass Company, LimitedInventors: Seiichi Katsuragawa, Chikashi Kawashima, Tomio Masaki
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Patent number: 4748204Abstract: A melt-processable fluororesin of wide use is obtained by blending 100 parts by weight of a soft and melt-processable fluorine-containing graft copolymer in which crystalline fluoro-polymer segments are grafted to an elastomeric fluoro-polymer segment and 1-90 parts by weight of a crystalline fluoro-polymer which comprises the structural units of the crystalline fluoro-polymer segments of the graft copolymer. For example, a graft copolymer obtained by graft copolymerization of vinylidene fluoride (VDF) with an elastomeric copolymer of VDF, chlorotrifluoroethylene and an unsaturated peroxy compound is blended with either homopolymer of VDF or a copolymer of VDF and another monomer. By the blending some important characteristics of the graft copolymer such as elastic modulus, hardness and melt flow rate are desirably modified without serious lowering of tensile strength and elongation.Type: GrantFiled: September 12, 1986Date of Patent: May 31, 1988Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Seiiti Minegishi, Shinji Ogasawara, Takashi Mukaino
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Patent number: 4652592Abstract: The disclosure relates to enhancement of mechanical strength and heat resistance of a graft copolymer which is obtained by graft copolymerization of a fluorine-containing monomer that gives a crystalline polymer, such as vinylidene fluoride, with an elastomeric copolymer having peroxy bond, such as a ternary copolymer of vinylidene fluoride, chlorotrifluoroethylene and an unsaturated peroxy compound. A small amount of triallylisocyanurate is mixed with the graft copolymer, and the mixture is formed into a desired shape by a usual method such as calendering or compression moulding. The shaping material is exposed to ionizing radiation such as gamma-ray, which causes cross-linking of the graft copolymer.Type: GrantFiled: July 11, 1985Date of Patent: March 24, 1987Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Shinji Ogasawara, Isao Tanaka, Yasufumi Koga
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Patent number: 4560737Abstract: A piezoelectric polymeric material in the form of sheet or film, which comprises polymers of vinylidene fluoride (VDF) as principle components. The piezoelectric material is essentially a mixture of 100 parts by weight of a VDF base resin, which may be either poly(VDF) or a copolymer, and 1-100 parts by weight of a copolymer of a fluoroelastomer and either VDF monomer or a monomer mixture containing a major amount of VDF monomer. A sheet or film having a high piezoelectric modulus is obtained by stretching a sheet or film of said mixture at an adequately elevated temperature and polarizing the sheet or film after or during the stretching thereby making the stretching sheet or film an electret.Type: GrantFiled: December 30, 1983Date of Patent: December 24, 1985Assignee: Central Glass Company, LimitedInventors: Kazuhiko Yamamoto, Kazumi Nejigaki, Takashi Yasumura, Chikashi Kawashima, Shuichi Inoue
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Patent number: 4472557Abstract: A fluorohydrocarbon resin that has elasticity and retains favorable properties of known fluorohydrocarbon polymers is obtained by graft copolymerization of a fluorine-containing elastomeric polymer with a fluorine-containing crystalline polymer. One of the elastomeric and crystalline polymers is prepared by copolymerizing at least one fluorine-containing monomer with at least one unsaturated monomer that has peroxy bond. When the elastomeric polymer is employed as the basic polymer and the crystalline polymer is polyvinylidene fluoride, the graft copolymerized fluorohydrocarbon resin is high in mutual solubility with polyvinylidene fluoride, so that the addition of this resin to polyvinylidene fluoride gives a resin composition which has elasticity and good low temperature characteristics.Type: GrantFiled: May 19, 1983Date of Patent: September 18, 1984Assignee: Central Glass Company, LimitedInventors: Chikashi Kawashima, Takashi Yasumura