摘要:
The installation includes elements for the temporary injection of inert gas; and at least one individual and autonomous casing (6) provided with a window (13) and including receiving elements for a support (3) carrying an ophthalmic lens (2), and sealing elements (21) adapted to form around the ophthalmic lens (2) a sealed enclosure, that enclosure including a non-return inlet member adapted to cooperate with the elements for the temporary injection of inert gas.
摘要:
The installation includes elements for the temporary injection of inert gas; and at least one individual and autonomous casing (6) provided with a window (13) and including receiving elements for a support (3) carrying an ophthalmic lens (2), and sealing elements (21) adapted to form around the ophthalmic lens (2) a sealed enclosure, that enclosure including a non-return inlet member adapted to cooperate with the elements for the temporary injection of inert gas.
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 mold for molding an optical element, in particular using a reaction injection molding method (RIM). The mold comprises a generally circular shaped, mold cavity having a geometrical center and a main plane, a sprue base with a longitudinal axis and a feed connection that makes the sprue base communicate with a feed sill of the mold cavity, the longitudinal axis of the sprue base and the geometrical center of the mold cavity defining a mold symmetry plane orthogonal to the main plane of the mold cavity, which intersection with said main plane defines a mold main axis, characterized in that the longitudinal axis of the sprue base together with a line perpendicular to the main plane of the mold cavity forms an angle ranging from 0 to 30°, preferably from 0 to 15°. Methods of using the mold and objects made thereby are also disclosed.
摘要:
The invention relates to a polymerisable liquid mixture comprising: (a) a polymerisable thermosetting composition which is a precursor by polymerization of a first thermoset polymer material, said composition containing at least one polythiol and/or one polyol, preferably a polythiol, and at least one polyiso(thio)cyanate; and (b) a second polymer material solubilized in the aforementioned polymerisable thermosetting composition, whereby the second material (i) contains at least one block copolymer comprising at least two polymer blocks A and B, namely an elastomer block A and a hydrophilic block B, and, following polymerization of the polymerisable mixture, (ii) forms domains which are rich in elastomer block A and which are dispersed throughout the first material, said domains being smaller than 80 nanometers and preferably smaller than 50 nanometers. The invention also relates to a transparent article having improved toughness, which is produced by means of polymerization of the above-mentioned polymerisable mixture, comprising an alloy of a first thermoset polymer material forming the matrix of said article and of a second polymer material which is dispersed throughout said first material. The aforementioned articles have improved resistance to impact and to crack propagation. The invention is suitable for use in ophthalmic optics.
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.
摘要:
The object of the invention is a process for molding an optical element such as a lens (2). According to the invention, the element is obtained by a reaction injection molding process comprising the steps of mixing at least two polymerizing reactants and forcing the obtained reacting mixture by an injection duct (5) for filling under pressure a scaled mold cavity (4) having an entry side (43) provided with a casting opening (42) and an evacuation side (44) and providing a laminated flow of mixture in a spout (6) having a progressive enlarging transversal section between the outlet opening (52) of the injection duct (5) and the casting opening (42) of the mold cavity (4), for avoiding any turbulent area in said laminated flow, said evacuation side (44) being provided with means (45) for evacuating air contained in the mixture during mold filling. The invention also covers the molding installation adapted for using such a process.
摘要:
A multilayer polarizing structure is produced on a temporary support. The structure comprises at least one orienting layer and one polarizing layer comprising dichroic dyes, the dichroic dyes having an angular orientation determined by the orienting layer. The multilayer structure is separated from the temporary substrate before being applied onto a surface of an optical element. Applying the structure onto the optical element may be easily carried out while obtaining a quality compatible with many uses of the optical element, in particular ophthalmic use.
摘要:
A method for producing an article which is made of a transparent material and devoid of visible surface lines consists in producing a substrate which is made of a transparent material having a refractive index ns, whose at least main face is machined and polished in such a way that the Ra value thereof ranges from 0.001 to 0.1 μm, but has visible surface defects in the form of thin individual scratches, in deposing, a liquid polymerisable composition of a masking coating, whose contact angle with said substrate main face is equal or less than 30° and which is formed by polymerising a masking coating having a refractive index nc such as 0.01
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).