Abstract: The method of the invention comprises: a) forming a hydrophilic polyurethane prepolymer with isocyanate end groups, by the polyaddition reaction of at least one polyol and at least one diisocyanate in the presence of at least one internal emulsifying agent; b) mixing the polyurethane prepolymer with a photochromic agent; c) adding water or a mixture of water and solvent, under agitation, to the mixture of the polyurethane prepolymer and the photochromic agent, to form an emulsion; and d) adding at least one chain extension agent to the emulsion and performing a chain extension reaction to give the final photochromic polyurethane latex. Application to the production of ophthalmic articles having photochromic properties.

Abstract: This invention relates to a method for preparing a photochromic latex, photochromic thin films obtained therefrom, and articles coated with such thin films, in particular photochromic ophthalmic lenses.

Abstract: This invention relates to a method for preparing a photochromic latex, photochromic thin films obtained therefrom, and articles coated with such thin films, in particular photochromic ophthalmic lenses.

Abstract: Described are photochromic polyurethane coatings that meet commercially acceptable “cosmetic” standards for optical coatings. Also described are articles having such coatings. The coatings exhibit a Fischer microhardness of from 50 to 150 Newtons per mm and improved photochromic properties, i.e., the formation of darker activated colors and faster rates of photochromic activation and fade when irradiated with ultraviolet light.

Abstract: This invention relates to a method for preparing a photochromic latex, photochromic thin films obtained therefrom, and articles coated with such thin films, in particular photochromic ophthalmic lenses.

Abstract: The invention relates to water-insoluble polymers which promote cell proliferation, contain carboxylate and sulfonate groups and are obtainable by free radical copolymerization of one or more aliphatically unsaturated monomers containing carboxylate groups, or the correspondingly functionalized derivatives of the monomers, as component I with one or more aliphatically unsaturated monomers containing sulfonate groups, or the correspondingly functionalized derivatives of the monomers, as component II and a component III which comprises an aliphatically unsaturated monomer or several aliphatically unsaturated monomers, the correspondingly functionalized derivatives being converted into carboxylate and sulfonate groups after the copolymerization, and to a process for their preparation, wherein the polymers are useful for forming articles which promote cell proliferation.

Abstract: The invention relates to water-insoluble polymers which promote cell proliferation, contain carboxylate and sulfonate groups and are obtainable by free radical copolymerization of one or more aliphatically unsaturated monomers containing carboxylate groups, or the correspondingly functionalized derivatives of the monomers, as component I with one or more aliphatically unsaturated monomers containing sulfonate groups, or the correspondingly functionalized derivatives of the monomers, as component II and a component III which comprises an aliphatically unsaturated monomer or several aliphatically unsaturated monomers, the correspondingly functionalized derivatives being converted into carboxylate and sulfonate groups after the copolymerization, and to a process for their preparation, wherein the polymers are useful for forming articles which promote cell proliferation.

Abstract: The invention relates to water-insoluble polymers which promote cell proliferation, contain carboxylate and sulfonate groups and are obtainable by free radical copolymerization of one or more aliphatically unsaturated monomers containing carboxylate groups, or the correspondingly functionalized derivatives of the monomers, as component I with one or more aliphatically unsaturated monomers containing sulfonate groups, or the correspondingly functionalized derivatives of the monomers, as component II and a component III which comprises an aliphatically unsaturated monomer or several aliphatically unsaturated monomers, the correspondingly functionalized derivatives being converted into carboxylate and sulfonate groups after the copolymerization, and to a process for their preparation, wherein the polymers are useful for forming articles which promote cell proliferation.

Abstract: A process for the emulsion polymerization in the presence of a stable free radical of at least one monomer which can be polymerized by the radical route, which emulsion comprises a liquid aqueous phase and a liquid organic phase, the aqueous phase comprising at least 50% by weight of water and the liquid organic phase comprising more than 50% by weight of monomer(s) to be polymerized. The invention results, by a rapid controlled polymerization process, in a latex of polymer particles, it being possible for the polymer to comprise acrylate and/or methacrylate blocks.

Abstract: This invention pertains to a process for the manufacture of a hydrophilic polymeric product, consisting in causing a material comprising a crosslinked silicone polymer matrix and photoinitiator groups dispersed and immobilized within the polymer matrix to swell in a swelling solution comprising a solvent for swelling the crosslinked silicone polymer of the matrix of the material, a photopolymerizable hydrophilic monomer and optionally a crosslinking agent and a proton- or electron-donating coinitiator compound, when the material comprises photoactivable photoinitiator groups and does not comprise proton- or electron-donating coinitiator groups causing the photopolymerizable hydrophilic monomer to diffuse into the swollen material, and polymerizing, by irradiation, the photopolymerizable hydrophilic monomer.

Abstract: A process is disclosed for preparing bioactive, covalently fixed coatings on the surfaces of substrates, by grafting to a surface of the substrate a coating polymer which contains the following monomers in copolymerized form: (i) at least one monomer of the general formula: R—(A)a  (I), in which R is a mono- or diolefinically unsaturated organic radical having a valence a, A is a carboxyl group, a sulfuric acid group, a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a phosphorous acid group, a phenolic hydroxyl group, or a salt of one of these acid groups, and a is 1, 2 or 3; and (ii) at least one monomer which is sensitive to UV radiation.

Abstract: The invention relates to water-insoluble, bacteriophobic and optionally cell proliferation-inhibiting polymers obtainable by free-radical polymerization of (a) at least one monomer of the general formula R—(A)a, in which R is an aliphatically unsaturated organic radical with the valence a, A is a carboxyl group —COOH, sulfuric acid group —OSO2OH, sulfonic acid group —SO3H, phosphoric acid group —OPO(OH)2, phosphonic acid group —PO(OH)2, phosphorous acid group —OP(OH)2, a phenolic hydroxyl group or a salt of one of the groups, and a is 1, 2 or 3, with the proviso that, if the monomer of the formula I contains a carboxyl group —COOH or a carboxylate group, either this monomer contains at least one further radical A having a different one of the definitions specified for A, or at least one further monomer of the formula I is also used in which A has a different one of the definitions specified for A; and (b) at least one other aliphatically unsaturated monomer, whe

Abstract: This invention pertains to a process for the manufacture of a hydrophilic polymeric product, consisting in causing a material comprising a crosslinked silicone polymer matrix and photoinitiator groups dispersed and immobilized within the polymer matrix to swell in a swelling solution comprising a solvent for swelling the crosslinked silicone polymer of the matrix of the material, a photopolymerizable hydrophilic monomer and optionally a crosslinking agent and a proton- or electron-donating coinitiator compound, when the material comprises photoactivable photoinitiator groups and does not comprise proton- or electron-donating coinitiator groups causing the photopolymerizable hydrophilic monomer to diffuse into the swollen material, and polymerizing, by irradiation, the photopolymerizable hydrophilic monomer.

Abstract: Disclosed is an original method for preparing composite materials for a display screen, these materials containing a polymer, liquid crystal and dye. The present problem is one of inserting molecules of dye into composites of this type. The disclosed method proposes the preparation, in a first step, of a porous film of reticulate polymer. Then, molecules of liquid crystal (XL) and molecules of dye (C) are made to diffuse therein by a polymer-expanding solvent. After evaporation of the solvent, a film of polymer is obtained with inclusions containing liquid crystal (XL) and dye (C) with a wide range of concentrations in liquid crystal, thus making it possible to optimize the performance characteristics in terms of contrast and control voltage of the screen thus made.

Abstract: Organo-lithium compounds of the formula: ##STR1## wherein R is an alkyl group of up to 5 carbon atoms, R' is either hydrogen or an alkyl group of up to 5 carbon atoms and n is an integer from 2 to 10. These bifunctional organo-lithium compounds are prepared without the use of any polar or complexing agent and are useful as polymerization initiators for the production of block copolymers.

Abstract: Organo-lithium compounds of the formula: ##STR1## wherein R is an alkyl group of up to 5 carbon atoms, R' is either hydrogen or an alkyl group of up to 5 carbon atoms and n is an integer from 2 to 10. These bifunctional organo-lithium compounds are prepared without the use of any polar or complexing agent and are useful as polymerization initiators for the production of block copolymers.

Abstract: Organo-lithium compounds of the formula: ##STR1## wherein R is an alkyl group of up to 5 carbon atoms, R' is either hydrogen or an alkyl group of up to 5 carbon atoms and n is an integer from 2 to 10. These bifunctional organo-lithium compounds are prepared without the use of any polar or complexing agent and are useful as polymerization initiators for the production of block copolymers.