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:
Jul. 10, 2007
Filed:
May. 28, 2003
Syuichiro Sanpei, Fukushima, JP;
Masayuki Hanzawa, Fukushima, JP;
Yasuyuki Suzuki, Fukushima, JP;
Minoru Kaeriyama, Kanagawa, JP;
Tomoya Hidaka, Chiba, JP;
Toru Kawabe, Niigata, JP;
Syuichiro Sanpei, Fukushima, JP;
Masayuki Hanzawa, Fukushima, JP;
Yasuyuki Suzuki, Fukushima, JP;
Minoru Kaeriyama, Kanagawa, JP;
Tomoya Hidaka, Chiba, JP;
Toru Kawabe, Niigata, JP;
Nippon Soda Co., Ltd., Chiyoda-ku, Tokyo, JP;
Abstract
A process for producing 4-isopropoxy-4'-hydroxydiphenyl sulfone useful as the developer for leuco dyes to be used in thermosensible papers, which is excellent in productivity, economical efficiency and safety and permits the production of the compounds from constantly available raw materials. This process is improved in productivity and economical efficiency as compared with those of the prior art both by shortening the production time by the use of an isopropyl iodide, which is more reactive than isopropyl bromide which have been used in the prior art.