Polarized lens of plastic lamination and the production method of the same
AssigneeNicoh Optical Co., Ltd.
InventorHokao Hayashi
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Abstract
A polarized lens of plastic lamination is provided, which lens is of high quality and highly durable in use while being inexpensively and stably producible without inconsistency in quality. The issues of the prior polarized plastic lens as produced by the blanking and hot machining method, the injection mold-heat bonding method or the sandwiching method are solved by making the most of the ductility and casting performance inherent in diethylene glycol bis(allyl carbonate) and combining therewith the optical characteristics of a polarized film made of poly(vinyl alcohol) resin as well as transparency and durability inherent in a polycarbonate resin plate so as to produce a polarized lens of plastic lamination.
Claims8
A polarized lens of plastic lamination wherein a concave side surface of a polarized film layer 1 made from poly(vinyl alcohol) resin is laminated through a polymerization setting layer 3 made from diethylene glycol bis(allyl carbonate) onto a convex side surface of a lens matrix layer 2 made from polycarbonate resin while on a convex side surface of said polarized film layer 1 a polymerization setting layer 4 made from ethylene glycol bis(allyl carbonate) is formed so as to provide a polarized lens of lamination structure.
A method for producing a polarized lens of plastic lamination comprising the steps of dropping a casting resin R of low viscosity essentially consisting of ethylene glycol bis(allyl carbonate) into a concave cavity C of a casting die D;
- overlaying a convex side surface of a polarized film 1′ made from poly(vinyl alcohol) resin onto said concave cavity C that corresponds to said convex side surface of said polarized film 1′ so as to uniformly spread and attach said casting resin R on said convex side surface of said polarized film 1′;
- dropping said casting resin R into a concave side surface of said polarized film 1′ and overlaying a convex side surface of a lens matrix plate 2′ made from polycarbonate resin onto said concave side surface of said polarized film 1′ with said casting resin R thereon so as to uniformly spread and attach said casting resin R on said convex side surface of said lens matrix plate 2′;
- polymerizing and setting said casting resin R as uniformly spread and attached on said convex side surfaces of said polarized film 1′ and said lens matrix plate 2′ under heat treatment so as to obtain an integral polarized lens prototype Lb;
- and performing finishing operation on said prototype Lb so as to produce a polarized lens L.
Dependencies are inferred from the claim text.