| 摘要 |
An emulsifier for use in forming a film for a suspended particle device (SPD) wherein the film is comprised of a cross-linked matrix polymer having a plurality of droplets of a liquid light valve suspension distributed therein. The emulsifier is formed of a copolymer material comprising at least first and second segments, the segments differing from one another in at least one of their chemical affinities, their compositions and their polarities. A first one of the segments is soluble in an uncured liquid matrix polymer used in forming the film, but insoluble in a liquid suspension medium of which the droplets are dispersed. A second segment is soluble in the liquid suspending medium in the droplets and insoluble in the uncured liquid matrix polymer. The first and second segments have substantially the same index of refraction and the index of refraction of the segments is within 0.010 of that of each phase of an emulsion formed with the emulsifier. In one embodiment, the first segment is comprised of a material selected from the group consisting of linear organosiloxanes, branched organosiloxanes, linear alkyl groups, branched alkyl groups, linear fluoroalkyl groups and branched fluoroalkyl groups. The second segment, in turn, is comprised of a material selected from the group consisting of linear esters, branched esters, linear (meth)acrylate, branched (meth)acrylate, linear amide, branched amide, linear amine, branched amine, linear epoxy groups, branched epoxy groups, linear groups comprising hydroxyl or acid groups and branched groups comprising hydroxyl or acid groups. The emulsifier is adapted to substantially prevent coalescence of the droplets of the liquid light valve suspension during formation of the film by retarding the growth of the droplets. ® KIPO & WIPO 2008 |
