The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 08, 2022
Filed:
Dec. 19, 2018
Shin-etsu Chemical Co., Ltd., Tokyo, JP;
Daisuke Kori, Joetsu, JP;
Seiichiro Tachibana, Joetsu, JP;
Tsutomu Ogihara, Joetsu, JP;
Satoru Kitano, Takasaki, JP;
Yukio Abe, Takasaki, JP;
Fumihiro Hatakeyama, Takasaki, JP;
Taiki Kobayashi, Isesaki, JP;
SHIN-ETSU CHEMICAL CO., LTD., Tokyo, JP;
Abstract
The invention provides: a dihydroxynaphthalene condensate which suppresses soft particle generation and is suitably usable for a composition excellent in filterability; and a method for producing the dihydroxynaphthalene condensate. In the method for producing a dihydroxynaphthalene condensate, dihydroxynaphthalene to be used has a sulfur element content of 100 ppm or less in terms of mass among constituent elements. The dihydroxynaphthalene and a condensation agent are condensed in presence of an acid or a base to produce the dihydroxynaphthalene condensate.