Japan Synthetic Rubber Co., Ltd.

Jsr Corporation

The Japan Steel Works, Ltd.

Kiyoshi Kasai

Masayuki Hattori

Nobuo Sakurai

Hiroshi Tadenuma

Satoshi Katayose

Hiromi Takeuchi

Kouji Tamori

Mitsuhiro Murata

Tetsuo Fukuta

Hisao Ono

Kinji Yamada

Nobuyuki Ito

Toshihiro Ogawa

Kunihiro Harada

Tatsuya Shimizu

Masayuki Takahashi

Eiji Takamoto

Norimasa Oda

Eitaro Okuya

Yoshiki Maki

Mikio Hikata

Masaru Ueno

Fujio Sakurai

Shiro Yasukawa

Osamu Kikuchi

Toru Masukawa

Masaaki Kitajima

Kakun Han

Haruhiro Hirai

A process for producing carrier polymer particles comprising covering the surface of organic polymer particles having a particle diameter of 0.1 to 20 micrometers with a saccharide by chemically bonding the organic polymers and the saccharide.

Carrier polymer particle, process for producing the same, magnetic particle for specific trapping, and process for producing the same

The organic polymer particles comprise a carboxyl group and 2,3-dihydroxypropyl group, and the magnetic particles for diagnostics comprise fine magnetic material particles and a polymer part containing a hydrophilic polymer part and a crosslinked polymer part, a dry coating film obtained from a water dispersion thereof having a contact angle with water of 5&#xb0; to 60&#xb0;. The process for producing the carboxyl group-containing particles comprises a step of producing an ester bond by reacting a hydroxyl group in organic polymer particles having the hydroxyl group with a carboxylic anhydride. The organic polymer particles comprise a hydroxyl group originating from a 2,3-dihydroxypropyl group and a polyoxyethylene group.

Organic polymer particles and process for producing the same, magnetic particles for diagnostics, carboxyl group-containing particles and process for producing the same, and probe-bound particles and process for producing the same

A particle for a diagnostic agent, which comprises a polymer particle comprising (A) from 20 to 100% by weight of a structural unit derived from at least one of acrylate having an aliphatic hydrocarbon group and methacrylate having an aliphatic hydrocarbon group, (B) from 0 to 10% by weight of a structural unit derived from unsaturated carboxylic acid, and (C) from 0 to 80% by weight of a structural unit derived from a vinyl monomer copolymerizable with the acrylate, methacrylate and unsaturated carboxylic acid, and a turbidmetric immunoassay using the same.

Particle for diagnostic agent and turbidmetric immunoassay using the same

Novel magnetic polymer particles which resists precipitation in an aqueous medium. The novel magnetic polymer particles can be widely used as carriers for diagnostics and immobilized enzymes, carriers for bacterial isolation, carriers for cell segregation, carriers for isolation and purification of ribonucleic acids and proteins, carriers for drug deliveries, and are usable as material for magnetic toners, magnetic inks, and magnetic coatings. The process for manufacturing the magnetic polymer particles comprising; dispersing a monomer mixture including a hydrophobic monomer containing more than 50% by weight of (meth)acrylic ester and a superparamagnetic substance in an aqueous medium to prepare an suspension, and polymerizing the monomers.

Magnetic polymer particle and process for manufacturing the same

Polymer particles prepared by polymerizing polymerizable monomers by seed polymerization, with far more excellent polymerization stability than conventional seed polymerization processes, in the presence of a polymer emulsion comprising low molecular weight polymer particles, radically polymerizable in an aqueous system. The polymer particles are present in an amount of 0.5-30 parts by weight (on solid basis) per 100 parts by weight of polymerizable monomers, have a weight average molecular weight of 500-10,000 and are prepared by emulsion polymerization or soap-free polymerization. The seed polymerization is carried out by initially charging less than 30% by weight of said polymerizable monomers to the polymerization mixture, and after the polymerization conditions are established, by continuously or intermittently adding the remaining portion of said polymerizable monomers to the reaction system.

Process for preparing polymer particles

Highly crosslinked polymer particles, which may be porous, consisting essentially of a non-hydrophilic polymer can be produced by adding a polymerizable monomer mixture comprising at least 20% by weight of at least one non-hydrophilic, crosslinking polyvinyl monomer to an aqueous dispersion containing a non-crosslinked, low molecular weight polymer particles having a weight average molecular weight of 500-10,000 as a dispersoid, with a non-reactive solvent in a proportion of not more than 1 part by weight per part by weight of the polymerizable monomer mixture, the proportion of the polymerizable monomer mixture plus the non-reactive solvent to the non-crosslinked, low molecular weight polymer particles being 4 to 20 parts by weight per part by weight of the non-crosslinked, low molecular weight polymer particles, and then subjecting the polymerizable monomer mixture to radical emulsion polymerization with stirring.

Highly crosslinked polymer particles and process for producing the same

Capsule-shaped polymer particles and a process for the production thereof are described. In one embodiment of the process, a polymerizable monomer component containing a cross-linkable monomer and a hydrophilic monomer, and an oily substance are finely dispersed in water to prepare an oil-in-water emulsion and then the polymerizable monomer component is polymerized, whereupon capsule-shaped polymer particles containing the oily substance as a core material are obtained. Upon removal of the oily substance in the particles, there are obtained capsule-shaped hollow polymer particles. These capsule-shaped polymer particles are excellent in such properties as mechanical strength and heat resistance, and thus can find many applications.

Capsule-shaped polymer particles and process for the production thereof

Microencapsulated particles each consisting of a mother particle of a core substance and a coating layer of daughter particles formed on the surface of said mother particle, which are obtained by stirring mother particles of a core substance having a number average particle diameter of 1 to 200 .mu.m and either or both of daughter particles (1) of a coating layer-forming material having a number average particle diameter of 1/5 of less of that of the mother particles and fragile daughter particles (2) of a coating layer-forming material having a number average particle diameter of more than 1/5 of that of the mother particles but having a fragility index (Fr) as defined in the specification of 5 or more, at a high speed in an air stream. Said microencapsulated particles can be used in various application fields such as coatings, electronic components and electronograph. In the electronograph filed, in particular, the microencapsulated particles can effectively be used as a toner capable of providing an image of high resolution and good quality.

Microencapsulated particles and process for production thereof

An aqueous dispersion of polymer particles each consisting essentially of (a) a syndiotactic 1,2-polybutadiene having 70% or more of unsaturated hydrocarbon groups in the side chains and having a melting point of 70.degree. C. or higher, (b) a polymer mixture of said polybutadiene (a) and other polymer in the form that (a) and (b) co-exist in the same particle, or (c) a copolymer obtained by graft-polymerizing a conjugated diene and/or other polymerizable monomer on said polybutadiene (a), each of said particles having an average diameter of 10 .mu.m or less. Said aqueous dispersion can be produced by a process comprising steps of adding, to an aqueous dispersion of a first catalyst component solution, a conjugated diene monomer and a second catalyst component and polymerizing said conjugated diene monomer, characterized in that the first catalyst component solution contains (A) a cobalt compound, (B) at least one member selected from the group consisting of alkali metals, organometallic compounds of metals of Groups I to III of the Periodic Table and hydrides of metals of Groups I to III of the Periodic Table, and (C) 1 to 1,000 moles, per mole of the cobalt compound (A), of a conjugated diene compound and then the second catalyst component is at least one compound selected from the group consisting of carbon disulfide, phenylisothiocyanic acid and a xanthogen compound.

Polymer particles and process for producing the same

A process for preparing large-sized polymer particles having a particle diameter in a range of 0.1 to 500 .mu.m by seeded polymerization is described, comprising:

Process for preparing large-sized polymer particles

When rubber is melted and decomposed in a screw extruder, a rubber melt can be produced without using a heavy oil with minimized evolution of gas by controlling the extruder cylinder temperature in the decomposing section of the screw within the range of 400.degree.-500.degree. C. and cooling the melt in the discharging section of the screw to a temperature of not more than 250.degree. C. The screw extruder suited for practising this method comprises a screw having a feeding section, a compressing section, a decomposing section and a discharging section which are arranged in that order from the inlet side, and a cylinder assembly consisting of a heating cylinder and a cooling cylinder arranged in that order from the inlet side, said feeding, compressing and decomposing sections of the screw being located corresponding to said heating cylinder, and said discharging section of the screw being located corresponding to said cooling cylinder.

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Kameyama, Japan

Kiyoshi Kasai