Nippon Paint Compnay, Ltd.

Shinichi Ishikura

Keizou Ishii

Ryuzo Mizuguchi

Akio Kashihara

Kazunori Kanda

Hisaichi Muramoto

Tadafumi Miyazono

Teruaki Kuwajima

Hiroshi Miwa

Katsuaki Kida

Tamotsu Yoshioka

Koichi Saito

Katsumi Mizuguchi

Yusuke Ninomiya

Yasuhiro Shibai

Akimitsu Uenaka

Atsushi Takahashi

Tsuyoshi Imamura

Keizo Ishii

Tamotu Yoshioka

Naoki Yamamori

Tamotsu Sobata

Hiroyuki Sakamoto

Naoya Yabuuchi

Yasuyuki Tsuchiya

Kenshiro Tobinaga

Takeo Kurauchi

Masanori Ohiwa

Masayuki Matsuda

Kiyoaki Higo

Jun Nozue

Minao Izumi

Atushi Takahashi

Shohachiro Yamaguchi

Masanori Oiwa

Hidetsumu Okada

Disclosed is a process for preparing crosslinked resin particles which comprises dispersing a resin having both a water-dispersible function and a self-crosslinkable function in one molecule in an aqueous medium and then three-dimensionally crosslinking.

Crosslinked resin particles and production thereof

The present invention provides a polyurea-covered particle having a narrow particle size distribution, which comprises a vinyl polymer particle as a seed particle and a polyurea cover layer formed on the vinyl polymer particle. The present invention also provides a process for producing the polyurea-covered particle having a narrow particle size distribution, which comprises:

Polyurea-covered particle having narrow particle size distribution and

Polymer particles having a small particle diameter and a narrow particle diameter distribution are obtained by a continuous polymerization method which does not accompany an increase of cohering products attaching to an inner face of a reaction vessel and an air-bubble invasion and, in which stirring of a material solution for polymerization is easy. An emulsion polymerization reaction or a suspension polymerization reaction is carried out by supplying a material solution for polymerization continuously to a clearance between coaxial double cylinders, which have stretched toward a direction crossing a horizontal plane, from the end side of the cylinders, by rotating at least one of the double cylinders round the axis and thereby, causing Taylor vortices. The polymer particles thus-formed are obtained by through from the other end side of the double cylinders to the outside.

Continuous polymerization method and apparatus

Polymer particles having a small particle diameter and a narrow particle diameter distribution are obtained by a continuous polymerization method which does not accompany an increase of cohering products attaching to an inner face of a reaction vessel and an air-bubble invasion and, in which stirring of a material solution for polymerization is easy. An emulsion polymerization reaction or a suspension polymerization reaction is carried out by supplying a material solution for polymerization continuously to a clearance between coaxial double cylinders, which have stretched toward a direction crossing a horizontal plane, from the end side of the cylinders, by rotating at least one of the double cylinders round the axis and thereby, causing Taylor vortices. The polymer particles thus-formed are obtained by through the other end side of the double cylinders to the outside.

Polymer microparticles having immobilized therein a water-insoluble substance such as oil-soluble dyes or pigments are produced by a method which includes the steps of forming droplets of a solution of a self-emulsifiable resin in a nonaqueous solvent containing the water-insoluble substance and an ethylenically unsaturated monomer suspended in an aqueous medium, and then allowing the monomer in the droplets to polymerize in situ.

Production of polymer microparticles having water-insoluble chemicals

Disclosed is composite hollow particles which are excellent in solvent resistance and mechanical stability and have strong walls and which can be easily synthesized. The composite hollow particles are prepared by uniformly dispersing the following ingredients in an aqueous medium;

Composite hollow particles

Disclosed is a photosensitive resin composition which has improved water developability and storage stability. The composition comprises

Photosensitive resin composition

Disclosed is an improved process of the post-emulsion method capable of forming crosslinked resin particles which do not have fusion bonds between particles and which have good storage stability and good redispersibility in an aqueous medium. The process comprises (a) dispersing in an aqueous medium a resinous component comprising (I) a base resin having a glass transition temperature (Tg) of 0.degree. C. or less and a polymerizable double bond, (II) a monomer which, when polymerized, provides a resin of which Tg is 20.degree. C. higher than that of said base resin, or a resin of which Tg is 20.degree. C. higher than that of the base resin, and (III) a polyvinyl compound; (b) crosslinking inside the dispersed resin particles and; (c) removing the aqueous medium therefrom.

Process for preparing crosslinked resin particles

Disclosed are pigment composite particles which are superior in water resistance, weather resistance, thermal stability and hardness. The pigment composite particles are prepared by suspension-polymerizing an aqueous suspension comprising

Pigment composite particles prepared by suspension polymorization

Novel crosslinked polymer microparticles having a mean grain diameter of 0.01 to 10.mu., whose polymer carries urea, urethane or amide groups. The invention also provides a coating composition containing said crosslinked polymer microparticles, which is excellent in application characteristics and storage stability and is capable of providing a coating with excellent film properties.

Crosslinked polymer microparticles and coating composition containing

Novel composite resinous film comprising a continuous phase of at least one resin and a discontinuous phase of microdomains which are aggregates of particles of at least one insoluble resin and are 0.03 to 10 microns in size, is provided. The film can exhibit the most desirous properties of the respective, constituent resinous materials and are useful in various fields including the paint industry.

Composite film and preparation thereof

The invention concerns a process for preparing composite resin particles having the so-called semi-IPN (inter penetration network) structure, in which linear thermoplastic polymer chains get entangled with a crosslinked polymer core through partial or thorough penetration. This method is very important in that both of the chain polymer and core polymer are freely selected from various resins.

Composite resin particles and preparation thereof

Novel composite film and preparation thereof

Composite resin particles each comprising a particulate crosslinked polymer to which a number of substantially linear, metal-containing polymer chains are chemically bonded. The invention also provide methods for the preparation of said composite resin particles. The present composite resin particles have self-film forming properties, can give a stable dispersion in an organic solvent or a resinous varnish and are specifically useful in paint industries. The particles are further characterized by having the desired properties of the metal element contained therein, as, for example, self-catalytic function in crosslinking, excellent biological activities and the like.

Growing community of inventors

Kyoto, Japan

Shinichi Ishikura