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:
Apr. 01, 2025
Filed:
Jun. 25, 2020
Kuraray Co., Ltd., Kurashiki, JP;
Takumi Takayama, Kurashiki, JP;
Kazutoshi Mishima, Kurashiki, JP;
Hiroyuki Konishi, Kurashiki, JP;
Kazuhiko Maekawa, Kurashiki, JP;
KURARAY CO., LTD., Kurashiki, JP;
Abstract
Disclosed is a vinyl alcohol-based block copolymer that is a block copolymer composed of a vinyl alcohol-based polymer block (B-b) and a copolymer block (B-c) comprising a vinyl alcohol-based monomer unit and an acrylic acid-based monomer unit, wherein a content (Z) of the acrylic acid-based monomer unit relative to all monomer units is 0.05 to 20.0 mol %, the block copolymer has a saponification degree of 80 to 99.99 mol %, the block copolymer has a number-average molecular weight (Mn) of 20,000 to 440,000, the block copolymer has a molecular weight distribution (Mw/Mn) of 1.05 to 1.95, and a ratio (DP/DP) of a number-average polymerization degree (DP) of the vinyl alcohol-based polymer block (B-b) to the number-average polymerization degree (DP) of the block copolymer is 0.010 to 0.999. The copolymer has a fine balance derived from the copolymer block (B-c) of having a superior solubility in water while being unlikely to undergo thickening or gelation due to pH fluctuation, and also has high mechanic strength derived from the vinyl alcohol-based polymer block (B-b).