Patent · US Expired

Method for the production and use of ultrapure water and apparatus therefor

US4784772A · kind A · utility

12Cited by
2References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1987
Grant dateNov 15, 1988
Priority date
Expiry dateJun 16, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S210/90
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.