公开(公告)号：US09862863B2

公开(公告)日：2018-01-09

申请号：US15278351

申请日：2016-09-28

Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.

Inventor： Toru Iwata ,  Akira Sugawa

IPC: C09G1/02 ,  B24B37/04 ,  G11B5/84 ,  C09K3/14 ,  C01B33/14 ,  C01B33/146 ,  C01B33/18

CPC classification number: C09G1/02 ,  B24B37/042 ,  B24B37/044 ,  C01B33/14 ,  C01B33/146 ,  C01B33/18 ,  C01P2004/62 ,  C01P2004/64 ,  C09K3/1409 ,  C09K3/1463 ,  G11B5/8404

Abstract: Embodiments of the invention provide a polishing composition including colloidal silica having an average particle size of 5 to 200 nm and pulverized wet-process silica particles having an average particle size of 0.1 to 1.0 μm, wherein a value of the ratio of the average particle size of the wet-process silica particles to that of the colloidal silica is from 2.0 to 30.0. The polishing composition, according to various embodiments, achieves a high polishing rate and has a good surface smoothness, without the use of alumina particles.

公开(公告)号：US10822525B2

公开(公告)日：2020-11-03

申请号：US15935925

申请日：2018-03-26

Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.

Inventor： Toru Iwata ,  Akira Sugawa

IPC: C09G1/02 ,  C09K3/14 ,  B24B37/00 ,  C09G1/16 ,  G11B5/84 ,  B24B37/04

Abstract: Embodiments provide a polishing composition containing colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound. According to at leaset one embodiment, the water-soluble polymer compound is a copolymer containing a structural unit derived from an unsaturated aliphatic carboxylic acid and a structural unit derived from an unsaturated amide.

公开(公告)号：US10662272B2

公开(公告)日：2020-05-26

申请号：US16169492

申请日：2018-10-24

Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.

Inventor： Akira Sugawa

IPC: C09K13/06 ,  C09G1/02 ,  C08F220/06 ,  C08F220/56 ,  C08F228/02 ,  C08K3/36 ,  C08K3/32 ,  C08K3/30 ,  C08K3/16 ,  C08K5/17 ,  C08K5/092 ,  C08F220/14 ,  C09G1/00

Abstract: Embodiments provide a polishing composition for a magnetic disk substrate containing colloidal silica, a water-soluble polymer, and water. The water-soluble polymer compound is a copolymer containing a monomer having a carboxylic acid group, a monomer having an amide group, and a monomer having a sulfonic acid group as essential monomers. The water-soluble polymer compound has a weight average molecular weight of 1,000 to 1,000,000.

公开(公告)号：US09856401B2

公开(公告)日：2018-01-02

申请号：US15278911

申请日：2016-09-28

Applicant: YAMAGUCHI SEIKEN KOGYO CO., LTD.

Inventor： Toru Iwata ,  Akira Sugawa

IPC: C09G1/02 ,  B24B37/04 ,  G11B5/84 ,  C09K3/14 ,  C01B33/14

CPC classification number: C09G1/02 ,  B24B37/042 ,  B24B37/044 ,  C01B33/14 ,  C01P2004/62 ,  C01P2004/64 ,  C09K3/1409 ,  C09K3/1463 ,  C09K3/1472 ,  G11B5/8404

Abstract: Embodiments of the invention provide a polishing composition including colloidal silica, pulverized wet-process silica particles, and a water-soluble polymer compound, wherein the water-soluble polymer compound is a polymer or copolymer having a constituent unit derived from an unsaturated aliphatic carboxylic acid. Various embodiments achieve a high polishing rate and obtain a good surface smoothness and end-face shape without the use of alumina particles.