Patents Assigned to Nippon Zeon Co. Ltd.
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Patent number: 5248746Abstract: A method of producing a polymer of a cationically polymerizable vinyl monomer by polymerizing at least one cationically polymerizable vinyl monomer using a polymerization initiator system composed of an organic compound having a functional group represented by formula (I) below ##STR1## where R.sup.1 represents a hydrogen atom, an alkyl group, or an aryl group; R.sup.2 represents an alkyl group, or an aryl group; X represents a halogen atom, an alkoxy group, or an acyloxy group, and a Lewis acid, wherein polymerization is carried out in the presence of a phosphorus-containing compound selected from the group consisting of a phosphine, a phosphine oxide, a phosphite, and a phosphate.Type: GrantFiled: April 2, 1991Date of Patent: September 28, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Yoshiharu Shimokawa, Yasuo Tsunogae, Shin-ichiro Tahara, Masami Kitaoka, Yoshitsugu Hirokawa
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Patent number: 5248736Abstract: There are provided a process for producing a diene polymer having markedly improved tensil strength and wear resistance and further having improved heat build-up, refound resilience, processability and wet skid resistance, as well as a rubber composition containing said diene polymer and having improved tensil strength, wear resistance, etc. Said diene polymer is produced by polymerizing a conjugated diene monomer or a mixture of the conjugated diene monomer and an aromatic vinyl monomer in a hydrocarbon solvent using a composite initiator containing an alkaline earth metal, and reacting active ends of the obtained active diene polymer with (a) a compound represented by the formula M.dbd.C.dbd.M (wherein M denotes an oxygen atom or a sulfur atom) or (b) N-substituted aminoketone, N-substituted thioaminoketone, N-substituted aminoaldehyde, N-substituted thioaminoaldehyde or a compound having an atomic group in a molecule represented by the formula --C(.dbd.M)--N< in a molecule.Type: GrantFiled: March 13, 1992Date of Patent: September 28, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Fumitoshi Suzuki, Yoshihiro Chino
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Patent number: 5247009Abstract: A rubber composition comprising a rubbery polymer and a modified liquid polymer. The modified liquid polymer is obtained by reacting a liquid polymer having at least one carbon-carbon double bond in the molecule with an organic compound having the group --CH.dbd.N-- and an organic acid halide having the group --COX where X is halogen, in the presence of a Friedel-Crafts catalyst.Type: GrantFiled: March 13, 1989Date of Patent: September 21, 1993Assignee: Nippon Zeon Co., Ltd.Inventor: Shizuo Kitahara
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Patent number: 5246994Abstract: A rubber composition containing (A) a mixture obtained by mixing (a1) 100 parts by weight of a highly saturated, ethylenically unsaturated nitrile-conjugated diene copolymer rubber whose copolymer chain contains not more than 30% by weight of conjugated diene units, and (a2) from 10 to 100 parts by weight of an ethylenically unsaturated monomer containing at least one carboxyl group, at least a proportion of the at least one carboxyl group being metal substituted such that a molar ratio of the at least one carboxyl group to the metal falls within a range of from 1/0.5 to 1/3; (B) an organic peroxide; and (C) a fatty acid amide, from 0.2 to 15 parts by weight of the (B) organic peroxide and from 0.5 to 20 parts by weight of the (C) fatty acid amide being added to 100 parts by weight of the (A) mixture.Type: GrantFiled: October 1, 1992Date of Patent: September 21, 1993Assignees: Tokai Rubber Industries, Ltd., Nippon Zeon Co., Ltd.Inventors: Akihiro Shibahara, Takao Sugiura, Tetsuo Ohyama, Yasunori Iwasaki
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Patent number: 5244743Abstract: Disclosed is a magnetic recording medium having a magnetic layer comprising a vinyl chloride copolymer as a binder and a magnetic powder and formed on a non-magnetic support. The binder is a mixture comprised of (a) a vinyl chloride copolymer having a quaternary ammonium salt and a hydroxyl group and (b) a vinyl chloride copolymer having at least one anionic hydrophilic group selected from carboxylic acids, sulfur-containing acids, phosphorus-containing acids, and salts thereof, and a hydroxyl group. The ratio of copolymer (a) to copolymer (b) is such that the equivalent ratio of the quaternary ammonium salt in copolymer (a) to the anionic hydrophilic group in copolymer (b) is from 0.2 to 5.Type: GrantFiled: February 26, 1990Date of Patent: September 14, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Katsuya Nakamura, Eitaro Nakamura
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Patent number: 5244955Abstract: There is provided an ethylenically unsaturated lower carboxylic acid metal salt-containing rubber composition having good mold releasability.This rubber composition is composed of preferably 5 to 100 parts by weight of an ethylenically unsaturated lower carboxylic acid salt preferably and 1 to 10 parts by weight of a higher fatty acid metal salt compounded with 100 parts by weight of rubber. Preferably 20 parts by weight or less of zinc oxide may further be compounded thereinto.Compared with conventional vulcanizates prepared using a mold coated with a mold release agent and vulcanizates prepared from a rubber composition to which silicone oil or the like was added, vulcanizates from the present rubber composition are ones wherein lowering of characteristics such as strength due to inclusion of these compounds is small and which have improved mold releasability.Type: GrantFiled: March 27, 1992Date of Patent: September 14, 1993Assignee: Nippon Zeon Co., Ltd.Inventor: Keiji Toyoda
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Patent number: 5244943Abstract: A nitrile group-containing rubber latex comprising an aqueous dispersion of a nitrile group-containing highly saturated rubber having an iodine value of not more than 120. The said rubber latex can be produced by converting a solution of a nitrile group-containing highly saturated polymer rubber having an iodine value of not more than 120 in an inert solvent into an oil-in-water emulsion using water and an emulsifier, and removing the solvent from the resulting emulsion.Type: GrantFiled: May 6, 1992Date of Patent: September 14, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Motofumi Oyama, Osamu Mori, Nagatoshi Sugi
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Patent number: 5239003Abstract: A process for preparing a styrene resin composition which comprises subjecting to bulk or bulk-suspension polymerization a solution obtained by dissolving (A) a modified styrene polymer obtained by introducing directly or through another atomic group at least one functional group represented by the general formula>C.dbd.N.sup.+ <into the polymer chain of a styrene polymer obtained by polymerizing 90 to 100% by weight of a styrene monomer with 0 to 10% by weight if a monomer copolymerizable with the styrene monomer, if desired together with (B) a rubber-like polymer in (C) a styrene monomer.Type: GrantFiled: November 27, 1991Date of Patent: August 24, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Hidenori Onishi, Hiroyuki Watanabe
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Patent number: 5235110Abstract: The invention discloses a process for preparing a 2,3-di-substituted cyclopentanone mixture containing an enriched cis-2,3-di-substituted cyclopentanone which comprises heating a trans-2,3-di-substituted cyclopentanone in the presence of 100 ppm or less (weight basis) of a metal carbonate based on the cyclopentanone. The invention also discloses a fragrant composition comprising 20 to 50 wt % of 2,3-di-substituted cis-methyl (dihydro) jasmonates and 80 to 50 wt % of 2,3-di-substituted (dihydro) trans-methyl (dihydro) jasmonates. The fragrant composition has jasmine flower-like fragrance.Type: GrantFiled: March 20, 1992Date of Patent: August 10, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Toshiro Yamada, Hiroshi Fujisawa, Hideyuki Tanaka
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Patent number: 5231125Abstract: A vinyl chloride resin plastisol can be prepared without the shearing action mixing conventionally required for mixing a resin and plasticizer, merely by immersing in a conventional plasticizer, aggregates in the form of a dry power and having an average diameter of 80 to 700 .mu.m of vinyl chloride resin particles; using a spray drying apparatus to form aggregates having an average diameter in the range from 80 to 700 .mu.m or by adding an organic fluid which is barely soluble in water and does not dissolve or swell the vinyl chloride resin to the aqueous dispersion of the vinyl chloride particles, followed by drying the aggregates thus formed at a temperature of 70.degree. C.or below.Type: GrantFiled: September 30, 1992Date of Patent: July 27, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Kouitu Kitazawa, Kouichi Ohrui
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Patent number: 5231138Abstract: A thermoplastic and elastomeric composition comprising a polyamide resin and a rubber component, wherein the rubber component is dispersed in the form of crosslinked particles in the polyamide resin.Type: GrantFiled: January 10, 1991Date of Patent: July 27, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Mitsuyoshi Aonuma, Tatsunosuke Suzuki, Satoru Isomura, Koichi Nishimura
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Patent number: 5229293Abstract: Recombinant Baculovirus in which the cDNA encoding E protein derived from Japanese encephalitis virus is integrated into the genome region non-essential to proliferation of Baculovirus under control of the promoter is infected to insect cells such as Sf9 cells, derived from Spodoptera frugiperda and the infected cells are cultured to express E protein of Japanese encephalitis. This E protein is useful as vaccines or diagnostics.Type: GrantFiled: May 5, 1989Date of Patent: July 20, 1993Assignees: Nippon Zeon Co Ltd., Tokyo Metropolitan Institute for Neurosciences, Yoshiharu MatsuuraInventors: Yoshiharu Matsuura, Kotaro Yasui, Takanori Sato
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Patent number: 5221582Abstract: A magnetic recording medium comprising a non-magnetic substrate and a magnetic powder-containing magnetic layer formed thereon, said layer further containing, as a binder for the magnetic powder, a vinyl chloride polymer containing 2% by weight or less of hydroxyl group(s) not directly bonding to the main chain and a polyurethane containing 2.3 or more isocyanate groups per molecule and having a molecular weight of 2,000 or more and the two polymers being crosslinked by each other.Type: GrantFiled: October 26, 1990Date of Patent: June 22, 1993Assignee: Nippon Zeon Co., Ltd.Inventor: Masahiro Yamakawa
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Patent number: 5219942Abstract: A rubber composition comprises as rubber components (A) 30-95 wt. % of an end-modified styrene-butadiene copolymer and (B) 70-5 wt. % of a diene rubber other than the end-modified styrene-butadiene copolymer (A). The end-modified styrene-butadiene copolymer (A) is obtained by reacting at least one compound to active terminals of a starting styrene-butadiene copolymer containing butadiene moieties, the trans-1,4 bond content of which is 70-95 wt. %, and having a styrene content of 5-60 wt. %. The at least one compound is selected from N-substituted aminoketones, N-substituted thioaminoketones, N-substituted aminoaldehydes, N-substituted thioaminoaldehydes and compounds containing in the molecules thereof an atomic group represented by the following formula: ##STR1## in which M stands for an oxygen or sulfur atom. The diene rubber (B) has a glass transition temperature higher than -60.degree. C.Type: GrantFiled: December 13, 1990Date of Patent: June 15, 1993Assignees: Nippon Zeon Co., Ltd., The Yokohama Rubber Co., Ltd.Inventors: Fumitoshi Suzuki, Yoshihiro Chino, Shuichi Akita
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Patent number: 5217839Abstract: Disclosed herein is a process for the preparation of a toner, which comprises dissolving or dispersing a compound having at least one >C.dbd.N.sup..sym. < bond in its molecule and a colorant in a vinyl monomer and then suspension-polymerizing the vinyl monomer in an aqueous dispersion medium.Type: GrantFiled: December 20, 1990Date of Patent: June 8, 1993Assignees: Nippon Zeon Co., Ltd., Casco Nobel ABInventors: Fumio Yamada, Hiromitsu Kikuchi, Tsuyoshi Yamamoto, Jun Saito, Shizuo Kitahara
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Patent number: 5218023Abstract: A rubber composition comprising a rubbery polymer, carbon black and a processing aid is described wherein the processing aid is a liquid diene polymer having a weight average molecular weight of about 5,000 to 140,000 and having an atomic group having a bond represented by the formula:>C.dbd.N.sup..crclbar. <,which is bonded to the terminal of the polymer chain, and the amount of the liquid diene polymer is 1 to 100 parts by weight per 100 parts by weight of the rubbery polymer. The liquid diene polymer is usually prepared by reacting an anionic living liquid diene polymer with a compound having in the molecule a bond represented by the formula: ##STR1## in which M represents an oxygen or sulfur atom.Type: GrantFiled: March 29, 1991Date of Patent: June 8, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Hiroyoshi Horikawa, Shuichi Akita, Hiroyuki Watanabe
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Patent number: 5217542Abstract: This invention relates to a method for producing surface-treated magnetic power for high record density magnetic recording medium which has excellent dispesibility and high filling density and surface smootheness.This invention provides a method for producing surface-treated magnetic powder characterized by treating magnetic powder with at least one functional group of the epoxy group, carboxyl group, hydroxyl group, thiol group and amino group and with hydrocarbon group having more than eight methylene chains.Type: GrantFiled: December 11, 1990Date of Patent: June 8, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Eitaro Nakamura, Katsuya Nakamura
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Patent number: 5216101Abstract: There are provided an acrylic copolymer elastomer containing an acrylic acid polyalkylene glycol ester as a constituent, and a vulcanizable composition comprising said elastomer and a vulcanizing agent, which composition gives a vulcanizate excellent in cold resistance, heat resistance and oil resistance. The acrylic copolymer elastomer is obtained by copolymerizing(a) 45 to 89.9% by weight of a monomer represented by the formula ##STR1## wherein R.sup.1 denotes an alkyl group having 1 to 8 carbon atoms, and/or a monomer represented by the formula ##STR2## wherein R.sup.2 denotes an alkylene group having 1 to 8 carbon atoms, and R.sup.3 denotes an alkyl group having 1 to 8 carbon atoms,(b) 10 to 45% by weight of a monomer represented by the formula ##STR3## wherein R.sup.4 denotes a hydrogen atom or a methyl group, R.sup.5 denotes a hydrocarbon group having 1 to 8 carbon atoms, m is an integer of 2 to 10, and n is an integer of 2 to 3,(c) 0.Type: GrantFiled: September 29, 1992Date of Patent: June 1, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Takafumi Kawanaka, Kiyoshi Hosoya
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Patent number: 5216080Abstract: A rubber composition comprising, as rubber components, 10-40 % by weight of (1) a styrene-butadiene copolymer rubber obtained by solution polymerization, having a styrene content of less than 20% by weight and a trans-1,4 bond content in butadiene portion, of more than 90% by weight and 60-90% by weight of (2) a diene rubber other than the styrene-butadiene copolymer rubber (1), having a glass transition temperature of -60.degree. C. or below.Type: GrantFiled: May 15, 1990Date of Patent: June 1, 1993Assignee: Nippon Zeon Co., Ltd.Inventors: Fumitoshi Suzuki, Shuichi Akita, Hiroyuki Watanabe
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Patent number: 5215849Abstract: A non-magnetic one-component developer suitable for use in a contact or non-contact development system. The developer comprises 100 parts by weight of colored fine particles, which comprises a binder resin and a colorant, and 0.3-10 parts by weight of at least one fine inorganic powder selected from (i) a fine inorganic powder (I) obtained by subjecting a fine inorganic powder having an average particle size of 0.1-10 .mu.m and a heating loss (under drying conditions of 150.degree. C. and 1 hour) of at most 1 wt.% to a hydrophobicity-imparting treatment with a silicone oil and (ii) a fine inorganic powder (II) obtained by subjecting a fine inorganic powder having an average particle size of 0.1-10 .mu.m to a two-step hydrophobicity-imparting treatment with at least one compound selected from silane coupling agents and silazane compounds and then further with a silicone oil.Type: GrantFiled: January 14, 1991Date of Patent: June 1, 1993Assignees: Nippon Zeon Co., Ltd, OKI Electric Industry Co., Ltd.Inventors: Yoshihiro Makuta, Mitsuo Ueno, Minoru Isobe, Hiroshi Kikuchi, Katsuyuki Ito