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:
Oct. 13, 2015
Filed:
Oct. 29, 2007
Hideki Kobayashi, Tokyo, JP;
Kunihiro Hayakawa, Tokyo, JP;
Masanobu Osawa, Tokyo, JP;
KURITA WATER INDUSTRIES LTD., Tokyo, JP;
Abstract
Disclosed are a method for further purifying ultrapure water, according to which any impurities in ultrapure water can be stably removed to a high degree within a small space over a prolonged period; and an apparatus therefor. Ultrapure water introduced into an ultrapure-water purifying apparatuspasses through an ion exchange resin layerin a lower chamber. During this process, metal ions, for example, in the ultrapure water are removed by the ion exchange resin. The ultrapure water then passes through a perforated plate, flows into an upper chamber, and permeates an ion exchange filter. During this process, metal ions and other impurities remaining unremoved by the ion exchange resin layerare removed. Specifically, metal ions are removed to a certain extent by the ion exchange resin, so that it is enough for the ion exchange filter provided downstream thereof to remove an extremely small amount of metal ions. Consequently, reaching of the ion exchange filter to breakthrough within a short period can be prevented, thereby attaining further purification of ultrapure water over a prolonged period of time.