Patents by Inventor Akihiko Hamada
Akihiko Hamada 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: 7015264Abstract: The present invention relates to (1) a deproteinizing agent for natural rubber latex, comprising a protease and one or more water-soluble polymers as an active component; (2) a deproteinized natural rubber latex, which is prepared by subjecting to a deprotenization treatment using the deproteinizing agent, and a method of producing the same; (3) a method of producing a rubber product, which comprises incorporating at least a vulcanizing agent into the latex (2), dipping a mold in the resulting compound latex, and vulcanizing and drying a rubber film formed on the mold; and (4) a method of producing a rubber product, which comprises incorporating at least a heat sensitizer and a vulcanizing agent into the latex (2), dipping a mold in the resulting heat-sensitive coagulable compound latex, and vulcanizing and drying a rubber film formed on the mold.Type: GrantFiled: July 10, 2003Date of Patent: March 21, 2006Assignee: Sumitomo Rubber Industries, Ldt.Inventors: Naoya Ichikawa, Yoshiaki Miyamoto, Akihiko Hamada
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Patent number: 6864305Abstract: A puncture sealing agent for a tire is at least comprising a rubber latex, an adhesive agent, and an antifreezing agent, wherein propylene glycol is used as the antifreezing agent, and further the ratio of the propylene-glycol to the total weight of the puncture sealing agent is set from 20 to 40% by weight.Type: GrantFiled: September 10, 2002Date of Patent: March 8, 2005Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Masahiro Kishida, Yoshihide Kojima, Kohei Takemura, Akihiko Hamada, Naoya Ichikawa
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Publication number: 20040014876Abstract: The present invention relates to (1) a deproteinizing agent for natural rubber latex, comprising a protease and one or more water-soluble polymers as an active component; (2) a deproteinized natural rubber latex, which is prepared by subjecting to a deprotenization treatment using the deproteinizing agent, and a method of producing the same; (3) a method of producing a rubber product, which comprises incorporating at least a vulcanizing agent into the latex (2), dipping a mold in the resulting compound latex, and vulcanizing and drying a rubber film formed on the mold; and (4) a method of producing a rubber product, which comprises incorporating at least a heat sensitizer and a vulcanizing agent into the latex (2), dipping a mold in the resulting heat-sensitive coagulable compound latex, and vulcanizing and drying a rubber film formed on the mold.Type: ApplicationFiled: July 10, 2003Publication date: January 22, 2004Applicant: Sumitomo Rubber Industries, Ltd.Inventors: Naoya Ichikawa, Yoshiaki Miyamoto, Akihiko Hamada
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Publication number: 20030050365Abstract: A puncture sealing agent for a tire is at least comprising a rubber latex, an adhesive agent, and an antifreezing agent, wherein propylene glycol is used as the antifreezing agent, and further the ratio of the propylene-glycol to the total weight of the puncture sealing agent is set from 20 to 40% by weight.Type: ApplicationFiled: September 10, 2002Publication date: March 13, 2003Inventors: Masahiro Kishida, Yoshihide Kojima, Kohei Takemura, Akihiko Hamada, Naoya Ichikawa
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Patent number: 6512034Abstract: Disclosed is a cationic graft-modified natural rubber latex, which is obtained by cationically modifying the graft-natural natural rubber latex with a cationic surfactant in the presence of a nonionic surfactant such as polyoxyalkylene alkyl phenyl ether, polyoxyalkylene monostyryl phenyl ether, polyoxyalkylene distyryl phenyl ether or polyoxyalkylene tristyryl phenyl ether, the obtained rubber latex being useful as an adhesive for fibers and papers.Type: GrantFiled: September 8, 2000Date of Patent: January 28, 2003Assignee: Sumitomo Rubber Industries, LtdInventors: Akihiko Hamada, Naoya Ichikawa
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Patent number: 6462159Abstract: Disclosed are a cationic deproteinized natural rubber latex, in which rubber particles are positively charged and the concentration of said rubber particles is from 40 to 65% by weight and that the viscosity at 25° C. of said latex is 200 mPa·s or less, a method of preparing said latex which comprises subjecting to a deprotenization treatment using a proteolytic enzyme and a deproteinizing agent made of one or more surfactant selected from cationic and nonionic surfactants, and optionally adding a post additive comprising a cationic or nonionic surfactant as an active component, thereby to enable both surfactants described above to coexist, and a treating agent used in the same.Type: GrantFiled: September 8, 2000Date of Patent: October 8, 2002Assignees: Sumitomo Rubber Industries, Ltd, Kao CorporationInventors: Akihiko Hamada, Naoya Ichikawa, Masaharu Hayashi
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Patent number: 6344499Abstract: A puncture sealing agent for sealing an inner surface of a tire comprises a deproteinized rubber latex that is formed by removing protein from a natural rubber latex. The puncture sealing agent includes nitrogen content at 0.1 wt. % or less of rubber solid content of the deproteinized rubber latex, and ammonia content at 0.5 wt. % or less of the rubber solid content.Type: GrantFiled: February 2, 2000Date of Patent: February 5, 2002Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Kazuhiko Kawamura, Tamisuke Kimura, Akihiko Hamada, Yoshiaki Miyamoto, Maiko Okada
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Publication number: 20010051675Abstract: The present invention relates to (1) a deproteinizing agent for natural rubber latex, comprising a protease and one or more water-soluble polymers as an active component; (2) a deproteinized natural rubber latex, which is prepared by subjecting to a deprotenization treatment using the deproteinizing agent, and a method of producing the same; (3) a method of producing a rubber product, which comprises incorporating at least a vulcanizing agent into the latex (2), dipping a mold in the resulting compound latex, and vulcanizing and drying a rubber film formed on the mold; and (4) a method of producing a rubber product, which comprises incorporating at least a heat sensitizer and a vulcanizing agent into the latex (2), dipping a mold in the resulting heat-sensitive coagulable compound latex, and vulcanizing and drying a rubber film formed on the mold.Type: ApplicationFiled: April 27, 2001Publication date: December 13, 2001Inventors: Naoya Ichikawa, Yoshiaki Miyamoto, Akihiko Hamada
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Patent number: 6277924Abstract: The present invention provides a solid golf ball which attains long flying distance and is superior in hit feeling and durability. The present invention provides a solid golf ball in which at least a portion thereof is made of rubber, wherein the rubber portion is a crosslinked, molded rubber composition comprising a base rubber, a co-crosslinking agent and peroxides, the base rubber comprising a polybutadiene modified with a tin compound and having a cis content of 40% or more.Type: GrantFiled: March 28, 1995Date of Patent: August 21, 2001Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akihiko Hamada, Kiyoto Maruoka
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Patent number: 6265479Abstract: Disclosed are a deproteinizing agent comprising a proteolytic enzyme and one or more cationic surfactants selected from the group consisting of an alkylamine salt, an alkylamine derivative and quaternized compounds thereof; and a method of preparing a cationic deproteinized natural rubber latex, which comprises adding said deproteinizing agent to a field latex or an ammonia-treated latex thereby subjecting the latex to a deproteinization treatment and purifying the rubber particles in the latex.Type: GrantFiled: September 8, 2000Date of Patent: July 24, 2001Assignees: Sumitomo Rubber Industries, Ltd., Kao Corp.Inventors: Naoya Ichikawa, Akihiko Hamada, Masaharu Hayashi
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Patent number: 6255382Abstract: The present invention provides a coated golf ball with excellent adhesion between the paint and the golf ball cover as well as superb durability. A coated golf ball comprises a golf ball body and a paint layer formed thereon, wherein the paint layer is formed from a carboxyl group-containing water dispersed polyurethane paint which is crosslinked by a carbodiimide compound.Type: GrantFiled: October 27, 1997Date of Patent: July 3, 2001Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akihiko Hamada, Kuniyasu Horiuchi
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Patent number: 6063837Abstract: A puncture sealing agent for sealing an inner surface of a tire comprises a deproteinized rubber latex that is formed by removing protein from a natural rubber latex. The puncture sealing agent includes nitrogen content at 0.1 wt. % or less of rubber solid content of the deproteinized rubber latex, and ammonia content at 0.5 wt. % or less of the rubber solid content.Type: GrantFiled: November 25, 1997Date of Patent: May 16, 2000Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Kazuhiko Kawamura, Tamisuke Kimura, Akihiko Hamada, Yoshiaki Miyamoto, Maiko Okada
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Patent number: 5981649Abstract: A rubber composition suitable for use in grips of articles such as golf clubs, tennis rackets, bicycles and tools, comprising (1) a rubber component containing an ethylene-propylene-diene rubber (EPDM), and (2) 5 to 100 parts by weight of a polyisobutylene having a viscosity average molecular weight of 6,000 to 50,000, which provides grips having good feeling of touch, good non-slipping properties in both fine and rainy weather, and giving a small feeling of impact to mis-shot of golf balls as compared with conventional grips.Type: GrantFiled: May 19, 1993Date of Patent: November 9, 1999Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Hidenori Hiraoka, Akihiko Hamada
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Patent number: 5967907Abstract: The present invention provides a multi-piece solid golf ball having excellent durability, excellent shot feel when hitting and good productivity. The present invention relates to a multi-piece solid golf ball which includes a solid core having a inner core and at least one outer core layer formed on the inner core, and a cover covering the solid core, wherein the inner core and outer core are formed from the material obtained by dispersing rubber in an ionomer resin and dynamically vulcanizing it with a vulcanizing agent, wherein the rubber particles dispersed in the ionomer resin have a particle size of not more than 10 .mu.m, the outer core layer has a Shore D hardness of more than that of the inner core by 5 to 30, and a weight ratio of the ionomer resin to the rubber particles is within the range of 95:5 to 30:70.Type: GrantFiled: October 28, 1997Date of Patent: October 19, 1999Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Kohei Takemura, Akihiro Nakahara, Akihiko Hamada
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Patent number: 5861465Abstract: A thread rubber for thread wound golf balls having a high impact resilience and high strength, wherein the thread rubber is obtained by vulcanizing a rubber composition which comprises (a) a rubber component selected from the group consisting of natural rubber, a synthetic high-cis-polyisoprene rubber and a mixture thereof, (b) at least one specific diaryl disulfide, (c) a vulcanizing agent, and (d) antioxidant; the compound (b) being present in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the rubber component (a).Type: GrantFiled: March 28, 1997Date of Patent: January 19, 1999Assignees: Sumitomo Rubber Industries, Ltd., Sumitomo Seika Chemicals Co., Ltd.Inventors: Akihiko Hamada, Atsuko Ochi, Satoshi Mano, Kuniyasu Horiuchi, Michio Suzuki
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Patent number: 5849392Abstract: The present invention provides a thread wound golf ball having improved flight performances, which comprises a solid center, a thread layer and an outer cover. The solid center is formed from a rubber component with crosslinked structure which contains an oily substance. Impact resilience of the solid center is 90 cm or more.Type: GrantFiled: June 7, 1993Date of Patent: December 15, 1998Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akihiko Hamada, Akira Kato, Keiji Moriyama, Kuniyasu Horiuchi, Tadahiro Ebisuno
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Patent number: 5833552Abstract: The present invention provides a golf ball having good shot feel and controllability and showing excellent rebound characteristics to give long flight distance. The golf ball of the present invention includes a core and a cover present on the core, an intermediate layer optionally being present between the core and the cover, wherein at least one layer of the cover or the intermediate layer has a thickness of 1 to 3 mm and is formed from a composition having an elasticity modulus (E*) at -30.degree. to +20.degree. C. of 1,000 to 9,000 Kgf/cm.sup.2 and a loss tangent at -30.degree. to +20.degree. C. of 0.02 to 0.1., and the core, whether solid core or thread wound core, has a spring constant at compression deformation of 15 to 60 Kgf/mm.Type: GrantFiled: January 17, 1997Date of Patent: November 10, 1998Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akihiko Hamada, Kouhei Takemura
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Patent number: 5816939Abstract: A thread rubber for golf balls, which has good aging resistance and rebound characteristics, and to a thread wound golf ball using the thread rubber are disclosed. The thread rubber for golf balls has a retention of tensile strength after aging 7 days at 70.degree. C. of not less than 70%, a hysteresis loss at a 100 Kg/cm.sup.2 constant stress tensile of not more than 50% and an elongation at a 100 Kg/cm.sup.2 constant stress elongation within the range of 900 to 1400%.Type: GrantFiled: March 28, 1997Date of Patent: October 6, 1998Assignees: Sumitomo Rubber Industries, Ltd., Sumitomo Seika Chemicals Co., Ltd.Inventors: Akihiko Hamada, Atsuko Ochi, Michio Suzuki
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Patent number: 5679745Abstract: The present invention provides a golf ball which does not cause poor impact resilience but provides long distance carry as well as good hit feeling, and keeps controllability nearly similar to balata covered thread wound golf balls. The present invention provides a golf ball which comprises a core and a cover for covering the core, wherein the cover comprises, as base component, a mixture of a sulfonate-type ionomer of which a polymer chain contains an elastomeric portion having rubber resilience and has a sulfonic group neutralized by a metallic ion, and a carboxylate type ionomer which is a copolymer of at least .alpha.-olefin and .alpha.,.beta.-unsaturated carboxylic acid of which a carboxyl group is neutralized by a metallic ion.Type: GrantFiled: September 6, 1995Date of Patent: October 21, 1997Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akihiko Hamada, Yoshikazu Yabuki
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Patent number: 5625003Abstract: The present invention provides a golf ball having excellent hit feeling and control property as well as excellent flying performance and cut resistance, which comprises a core and a cover for covering the core, wherein a heated mixture of an ionomer resin and a polymer containing a glycidyl group is used as a main component of a base resin for the cover.Type: GrantFiled: February 16, 1993Date of Patent: April 29, 1997Assignee: Sumitomo Rubber Industries, Ltd.Inventors: Akira Kato, Kuniyasu Horiuchi, Akihiko Hamada