Photochromic polyurethane laminate
AssigneeVision-Ease Lens, Inc.
InventorsXuzhi Qin, Hideyo Sugimura, Michael Boulineau
Life of this patent
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Abstract
A photochromic polyurethane laminate that is constructed to solve certain manufacturing difficulties involved in the production of plastic photochromic lenses is disclosed. The photochromic laminate includes at least two layers of a resinous material and a photochromic polyurethane layer that is interspersed between the two resinous layers and which contains photochromic compounds. The polyurethane layer is formed by curing a mixture of a solid thermoplastic polyurethane, at least one isocyanate prepolymer, at least one photochromic compound, and a stabilizing system.
Claims19
A photochromic polyurethane laminate comprising:
- a first resin sheet;
- a second resin sheet;
- a photochromic polyurethane layer, said photochromic polyurethane layer including a photochromic compound dissolved therewithin, said photochromic polyurethane layer having a top side and a bottom side, said top side bonded to said first resin sheet and said bottom side bonded to said second resin sheet;
- and
- wherein said photochromic polyurethane layer is formed by curing a mixture of a solid thermoplastic polyurethane and at least one isocyanate polyurethane prepolymer and at least one photochromic compound.
A process for producing a transparent photochromic polyurethane laminate, comprising:
- a) preparing a solvent casting solution by dissolving a solid thermoplastic polyurethane, at least one isocyanate polyurethane prepolymer, at least one photochromic compound, and optional stabilizers in a proper solvent;
- b) casting the solution on a release liner film;
- c) drying the solvent from the cast film to a substantially dry state to form a photochromic polyurethane film;
- d) transfer-laminating the photochromic polyurethane film between two transparent resin sheets;
- e) curing the photochromic polyurethane film, thereby forming a photochromic polyurethane laminate.
A process for producing a transparent photochromic polyurethane laminate, comprising:
- a) preparing a solvent casting solution by dissolving a solid thermoplastic polyurethane, at least one isocyanate polyurethane prepolymer, at least one photochromic compound, and optional stabilizers in a proper solvent;
- b) casting the solution on the first transparent resin sheet;
- c) drying the solvent from the cast film to a substantially dry state to form a photochromic polyurethane film;
- d) laminating the film to the second transparent resin sheet;
- e) curing the photochromic polyurethane film, thereby forming a photochromic polyurethane laminate.
Dependencies are inferred from the claim text.