Patent · US Expired

Filters employing both acidic polymers and physical-adsorption media

US6740147B2 · kind B2 · utility

13Cited by
47References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 4, 2001
Grant dateMay 25, 2004
Priority date
Expiry dateMay 4, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S95/901
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A filter includes at least two different adsorptive media. First, chemisorptive media, which is porous and includes an acidic functional group, is used to remove molecular bases, including ammonia, organic amines, imides and aminoalcohols, from the atmosphere used in semiconductor fabrication and other processes that require uncontaminated gaseous environments of high quality. Second, physisorptive media is able to adsorb condensable contaminants, particularly those having a boiling point greater than 150 degrees C. The physisorptive media can include untreated, activated carbon.

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