摘要:
The invention relates to polyurethane resins for producing impact-resistant optical lenses, in particular ophthalmic lenses made by using said resins and to a method for producing said lenses, in particular for using thermosetting polyurethane resin for producing the optical lenses, wherein said resin comprises a part (I) corresponding to an isocyanate part containing. A) a methylene-bis-4,4′-isocyanatecyclohexane (Hi2MDI), b) a prepolymer obtainable by the reaction between propoxilated glycerol and a methylene-bis-4,4′-diisocyanatecyclohexane and a part (II) corresponding to an alcohol part containing: c) an alkoxylated etherate glycerol in the monomer and oligomer form thereof and d) at least one type of a polyalkoxylated tertiary diamine tetraol and/or triol.
摘要:
The invention relates to an optical article comprising a substrate coated with an abrasion- and scratch-resistant coating composed of a lower layer and an upper layer that do adhere to each other, the upper layer and the lower layer being layers of cured upper and lower layer compositions, said upper layer composition comprising at least one organosilane, or a hydrolyzate thereof, of formula RnYmSi(X)4-n-m and at least one compound, or a hydrolyzate thereof, of formula M(Z)x, the following ratio being lower than 2.3: Rs = theoretical dry matter weight of compounds I in the upper layer composition theoretical dry matter weight of compounds I I in the upper layer composition said lower layer composition comprising at least one organosilane, or a hydrolyzate thereof, of formula R′n′Y′m′Si(X′)4-n′-m′ and, optionally, at least one compound, or a hydrolyzate thereof, of formula M′(Z′)y, the following ratio being higher than 2.3: Ri = theoretical dry matter weight of compounds III in the lower layer composition theoretical dry matter extract of compounds I V in the lower layer composition In the hereabove formulas, M and M′ are metals or metalloids of valences x and y, at least equal to 4, R and R′ groups are monovalent organic groups that are bound to silicon through a carbon atom and that contain at least one epoxy function, X, X′, Z and Z′ groups are hydrolyzable groups, Y and Y′ are monovalent organic groups that are bound to silicon through a carbon atom, n, m, n′ and m′ being integers such that n and n′=1 or 2 with n+m and n′+m′=1 or 2.
摘要:
A method for preparing a colloidal solution of non-aggregated zirconia particles, comprising the following steps: a) providing a zirconium hydroxide sol, b) adding to said sol an inorganic acid according to an [inorganic acid]/[Zr] molar ratio of
摘要:
A method for preparing a colloidal solution of non-aggregated zirconia particles, comprising the following steps: a) providing a zirconium hydroxide sol, b) adding to said sol an inorganic acid according to an [inorganic acid]/[Zr] molar ratio of
摘要:
The present invention relates to a method for the preparation of a transparent moulding comprising a blend of a thermoset polymeric material forming the matrix of said article, and a thermoplastic polymeric material, dispersed within said thermoset polymeric material, said process comprising at least the following stages: i) preparation of a liquid polymerizable mixture by dissolving said thermoplastic polymeric material in a thermosetting composition that is a precursor of said matrix, ii) filling of a mould with the liquid polymerizable mixture prepared in stage i), iii) polymerization of the liquid polymerizable mixture until a hardened blend of polymers is obtained, and iv) removal of the moulding formed by said blend of polymers, said process being characterized by the fact that the thermosetting composition comprises at least 60% by weight of 4,4′-di(ethoxyethyl)-bisphenol A dimethacrylate and at least 12% by weight of at least one monofunctional or multifunctional acrylic comonomer and by the fact that the thermoplastic polymeric material comprises at least one polystyrene-block-polybutadiene-block-poly(methyl methacrylate) (PS-b-PB-b-PMMA) triblock copolymer. The invention also relates to a transparent moulding obtained by this method as well as the polymerizable liquid mixture prepared in stage i).
摘要:
The present invention relates to a method of preparing a transparent moulding comprising a blend of a first thermoset polymeric material forming the matrix of said moulding, and of a second polymeric material dispersed within said first material, said method comprising at least the following stages: i) preparation of a liquid polymerizable mixture by dissolving said second polymeric material in a thermosetting polymerizable composition that is a precursor of said first thermoset polymeric material, ii) filling of a mould with the liquid polymerizable mixture obtained in stage i), iii) cooling of the liquid polymerizable mixture in the mould to a temperature T less than or equal to 0° C., iv) initiation of the polymerization of said cooled liquid polymerizable mixture at a temperature T′ less than or equal to 0° C., v) continuation of the polymerization of said liquid polymerizable mixture until a hardened blend of polymers is obtained, and vi) removal of the moulding formed from said blend of polymers from the mould. The invention also relates to a transparent moulding obtainable by such a method comprising a blend of polymers, at least one of which is a thermosetting polymer.