Kuraray Co., Ltd.

Shunji Kaneda

Chihiro Okamoto

Shinya Kato

Akira Kubotsu

Hirofumi Kikuchi

Ryuhei Ueeda

Kenji Okuno

Kiyonobu Fujii

Chihiro c/o Kuraray Co Ltd Okamoto

The subject is to provide a polymer material which enables to improve planarity and planarization efficiency of a polished surface and is useful as a polishing pad which generates only a few scratches. The said subject is solved by a polymer material having a tensile modulus at 50&#xb0; C. after saturation swelling with 50&#xb0; C. water of 130 to 800 MPa, a loss tangent at 50&#xb0; C. of not more than 0.2, and a contact angle with water of not more than 80&#xb0;.

Polymer material, foam obtained from same, and polishing pad using those

The present invention aims to provide a polyurethane foam, suitably usable as a polishing pad, having a uniform foam structure, which can achieve the improvements in the flatness of the surface of polished materials and in the planarization efficiency, and can extend the polishing pad life longer than that of the conventional polyurethane foams. This aim can be achieved by providing a polyurethane foam having a density of 0.5 to 1.0 g/cm, a cell size of 5 to 200 &#x3bc;m and a hardness [JIS-C hardness] of not less than 90, comprising a thermoplastic polyurethane which is obtained by a reaction of a high polymer polyol, an organic diisocyanate and a chain extender, contains not less than 6% by weight of a nitrogen atom derived from the isocyanate group, and has a storage elastic modulus measured at 50&#xb0; C. [E'] of not less than 5&#xd7;10dyn/cm.

Thermoplastic polyurethane foam, process for production thereof and polishing pads made of the foam

Incorporation in a thermoplastic resin of a mass of mica flakes having a median shape factor of not less than 0.76, an average particle size of not more than 2,000 .mu.m and an average aspect ratio of not less than 10 followed by molding gives moldings which are high not only in mechanical strength but also in strength at weld parts. Incorporation of said mica flake mass in a thermosetting resin followed by molding affords moldings very high in strength as well as in modulus of elasticity.

Mica flake mass and resin composition with the same incorporated therein

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Kurashiki, Japan

Shunji Kaneda