摘要:
Tabular gain silver halide emulsions prepared in the presence of a block copolymer selected from the group consisting of: A--B, A--(B--A).sub.m, B--(A--B).sub.m, (A--B).sub.p --X, (B--A).sub.p --X, �A--(B--A).sub.m !.sub.p --X, and �B--(A--B).sub.m !.sub.p --X where m is an integer of 1 or more, p is an integer of 3 or more, X represents a p-valent linking group, A represents a poly(tetrahydrofuran) block, and B represents a poly(ethylene oxide) block.
摘要:
Polymer optical core fiber made from homopolymers of 1,1-dihydroperfluorocyclohexylmethyl methacrylate and co-polymers thereof with other .beta.-fluorinated (meth)acrylates and polymethyl methacrylate are disclosed that have low optical loss.
摘要:
An organic photoreceptor that includes:(a) a charge transport compound having the formula ##STR1## where n is an integer between 2 and 6, inclusive; R.sup.1 and R.sup.2, independently, are an alkyl group, a cycloalkyl group, or an aryl group, or R.sup.1 and R.sup.2 combine with the nitrogen atom to form a ring;Y is a bond, a carbon atom, a --CR.sup.3 group, an aryl group, a cycloalkyl group, or a cyclosiloxyl group;R.sup.3 is hydrogen, an alkyl group, or an aryl group; andX is a linking group having the formula --(CH.sub.2).sub.m -- wherein m is an integer between 4 and 10, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, or an ester group;(b) a charge generating compound; and(c) an electroconductive substrate.
摘要:
An organic photoreceptor that includes:(a) a charge transport compound having the formula ##STR1## where n is an integer between 2 and 6, inclusive; R.sup.1 and R.sup.2, independently, are an alkyl group, a cycloalkyl group, or an aryl group, or R.sup.1 and R.sup.2 combine with the nitrogen atom to form a ring;Y is a bond, a carbon atom, a --CR.sup.3 group, an aryl group, a cycloalkyl group, or a cyclosiloxyl group;R.sup.3 is hydrogen, an alkyl group, or an aryl group; andX is a linking group having the formula --(CH.sub.2).sub.m -- where m is an integer between 4 and 10, inclusive, and one or more of the methylene groups is optionally replaced by an oxygen atom, a carbonyl group, or an ester group;(b) a charge generating compound; and(c) an electroconductive substrate.
摘要:
A method of chemical sensitisation which comprises providing a silver halide emulsion containing negative-acting silver halide grains, and adding to said silver halide emulsion a sulphur releasing organic polymer having multiple sulphur releasing groups per polymer molecule. The polymer preferably has at least 10 sulphur releasing groups per molecule which may be selected from thiocarbonate, dithiocarbonate, trithiocarbonate, dithioester, thioamide, thiocarbamate, dithiocarbamate, thiouram, thiourea, dithiooxamide, thioketone and trisulphide.
摘要:
A method for manufacturing a microporous film comprising the steps of: (a) providing a first polymer which is a hydrophobic thermoplastic polymer and a second polymer which is a hydrophilic polymer or copolymer of N-vinylpyrrolidone; (b) dissolving said first and second polymers in a solvent system which is compatible with both polymers, said solvent system comprising a blend of an aprotic organic solvent and an alcohol; (c) coating the resulting solution on a support; (d) effecting at least a partial drying of the resulting coating; and (e) washing the coating in an aqueous medium so as to extract at least 50% by weight of the said second polymer.