Patent · US Expired

Light valve containing liquid suspension including polymer stabilizing system

US4273422A · kind A · utility

29Cited by
22References
29Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 5, 1979
Grant dateJun 16, 1981
Priority date
Expiry dateMar 5, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/172
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A light valve for controlling the transmission of radiation, which comprises a cell and a liquid suspension in said cell; said liquid suspension comprising: PA1 an electrically resistive liquid suspending medium; PA1 a plurality of small, anisometrically shaped particles suspended in said suspending medium; PA1 a copolymer of at least two different monomers, at least one of said monomers having a sterically unhindered functional group for bonding to or associating with said particles, and at least one of said monomers having a branched group, the distance from the backbone of the copolymer to said sterically unhindered functional group most distant from the backbone being less than the distance from the backbone to the terminal group of said branched group, the branched groups in said copolymer being sufficiently soluble so that the copolymer as a whole is substantially dissolved in said liquid suspending medium; and PA1 a polymer dissolved in said liquid suspending medium and bonded to or associated with said copolymer but not said particles; the amount of said copolymer and said associated polymer being at least sufficient to inhibit agglomeration of said particles.

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