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:
Feb. 25, 2003
Filed:
Oct. 01, 2001
Shingo Yoshida, Osaka, JP;
Masahiro Motoyuki, Osaka, JP;
Tomoki Uemura, Osaka, JP;
Koji Yamamoto, Kobe, JP;
Abstract
The present invention provides a method for manufacturing a highly pure 2,6-dimethylnaphthalene having a purity of 99% or more even when a mixture of dimethylnaphthalene isomers containing 5 wt % or more of 2,7-dimethylnaphthalate is used as a feedstock. The method for manufacturing 2,6-dimethylnaphthalene comprises a step of performing crystallization and solid-liquid separation of a liquid primarily containing dimethylnaphthalene isomers so that the liquid is separated into a cake containing the dimethylnaphthalene isomers and a mother liquor, and a step of performing separation/purification of the cake. In the method described above, the crystallization and the solid-liquid separation are performed under the condition in which the ratio of the content of 2,6-dimethylnaphthalene in the mother liquor to that of 2,7-dimethylnaphthalene therein is not less than 1 so that the content of 2,6-dimethylnaphthalene in the cake is 60% or more and that the content of 2,7-dimethylnaphthalene therein is 6.5% or less. As a result, a highly pure 2,6-dimethylnaphthalene is obtained by performing the separation/purification of the cake.