| 摘要 |
This invention relates to a light valve, comprising a cell containing a suspension of particles in a liquid suspending medium comprising an electrically resistive, chemically inert liquid, the liquid suspending medium having dissolved therein an A-B type block polymer having a number average molecular weight of from about 10,000 to about 1,000,000, for example poly(12-hydroxystearic acid) having one terminal group capped, and comprising an organic solvating segment having at least one alkyl branch per repeat unit and an anchoring segment comprised of at least one polar group or a group that chelates positive ions, the anchoring segment constituting less than about 10% by weight of said block polymer. The liquid may be a low molecular weight, liquid fluorocarbon polymer having a specific gravity at room temperature of at least 1.5 and having at least about 50% of its atoms constituted by halogen atoms, at least 60% of the halogen atoms being fluorine and the balance chlorine and/or bromine, and an electrically resistive organic liquid miscible with the fluorocarbon liquid.
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