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. 22, 2014
Filed:
May. 27, 2010
Kazuhiko Sakamoto, Himeji, JP;
Koji Ueno, Himeji, JP;
Yoshitake Ishii, Himeji, JP;
Harunori Hirao, Himeji, JP;
Satoshi Nakagawa, Himeji, JP;
Kazuhiko Sakamoto, Himeji, JP;
Koji Ueno, Himeji, JP;
Yoshitake Ishii, Himeji, JP;
Harunori Hirao, Himeji, JP;
Satoshi Nakagawa, Himeji, JP;
Nippon Shokubai Co., Ltd., Osaka, JP;
Abstract
PROBLEM There is provided a melting method of (meth)acrylic acid crystal which is capable of providing a higher quality of (meth)acrylic acid without carrying out an additional purification treatment to (meth)acrylic acid obtained by a crystallization operation accompanied by melting of (meth)acrylic acid. In addition, there is provided a simple method for adjusting a content of polymerization inhibitor in a product (meth)acrylic acid. SOLUTION In the crystallization method melting (meth)acrylic acid crystal while wetting with the crystalline molten liquid, a polymerization inhibitor is added to a molten liquid melted after initiation of melting, and all of crystal is melted while circulating and feeding the molten liquid containing said polymerization inhibitor to the crystal. In addition, a content of polymerization inhibitor in product (meth)acrylic acid is adjusted by adding a predetermined amount of polymerization inhibitor corresponding to a product specification to the molten liquid melted after initiation of melting.