Patent · US Active

Electret materials

US7666931B2 · kind B2 · utility

4Cited by

7References

17Claims

0Family size

Assignee

Ciba Specialty Chemicals Corporation · US

Inventors

Hui Chin · Katonah, US
Matthew E. Gande · New Fairfield, US
Andrew J. Leggio · Franklin Square, US

Key dates

Filing date	Apr 3, 2007
Grant date	Feb 23, 2010
Priority date	—
Expiry date	Jan 31, 2028

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T442/60
WIPO fieldElectrical machinery, apparatus, energy
WIPO sectorElectrical engineering

Abstract

Disclosed are electret materials with outstanding thermal and charge stability. The electret materials comprise a melt blend of a thermoplastic polymer and one or more hindered hydroxylamine ester compounds that comprise at least one moiety of the formula Iwhere Ra′ is a monoacyl or diacyl radical; R1-R4 are each C1-C6alkyl; and

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