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:
Nov. 15, 1988
Filed:
Jun. 16, 1987
Yoshihisa Gotoh, Yokohama, JP;
Toshihiko Tutumi, Yokohama, JP;
Toshiaki Takahashi, Hatano, JP;
Katsuhiko Ito, Kawasaki, JP;
Mitsui Toatsu Chemicals, Incorporated, Tokyo, JP;
Abstract
Ultrapure water are produced and used by subjecting deionized water, which has been obtained from a deionization step making use of an ion-exchange resin, successively to a sterilization treatment, an activated carbon treatment, an ion-exchange resin treatment and a permeable membrane treatment. The water is fed from each of the steps of the treatments after at least the sterilization tretment (inclusive) to the next step through first piping made of a crystalline polyether ether ketone resin having a recurring unit of the following formula: ##STR1## The thus-produced ultrapure water is then fed through second piping, which is also made of the crystalline polyether ether ketone resin, to and through a use system of the ultrapure water.