Laminate and optical article comprising the same

1. A laminate comprising a pair of polycarbonate optical sheets or films which are laminated together through a polarizing film layer and an adhesive layer of a photochromic composition comprising (I) a polyurethane urea resin and (II) a photochromic compound,

wherein the photochromic composition further comprises (III) a polyisocyanate compound having at least two isocyanate groups in the molecule, and the polyisocyanate compound having at least two isocyanate groups in the molecule (III) comprises (IIIA) a compound having an isocyanate group bonded to a secondary carbon and (IIIB) at least one compound selected from the group consisting of hexamethylene diisocyanate, burette compound of hexamethylene diisocyanate, isocyanurate compound of hexamethylene diisocyanate and adduct compound of hexamethylene diisocyanate.

2. The laminate according to claim 1 , wherein the weight average molecular weight/number average molecular weight ratio indicative of polydispersity of the polyurethane urea resin (I) is 1.6 to 2.4.

3. The laminate according to claim 1 , wherein the polyisocyanate compound having at least two isocyanate groups in the molecule (III) comprises 100 parts by mass of the compound having an isocyanate group bonded to a secondary carbon (IIIA) and 20 to 150 parts by mass of at least one compound (IIIB) selected from the group consisting of hexamethylene diisocyanate, burette compound of hexamethylene diisocyanate, isocyanurate compound of hexamethylene diisocyanate and adduct compound of hexamethylene diisocyanate.

4. The laminate according to claim 1 , wherein the polyurethane urea resin (I) is a reaction product of (A) a urethane prepolymer having an isocyanate group at the end of the molecule, (B) a polyamine compound having at least two amino groups in the molecule and (C) a compound having one group able to react with an isocyanate group in the molecule.

5. The laminate according to claim 1 , wherein the polycarbonate optical sheet or film and the polarizing film layer and/or the polarizing film layer and the adhesive layer of the photochromic composition are laminated together through an adhesive layer containing no photochromic compound.

6. The laminate according claim 5 , wherein the softening points of the adhesive layer of the photochromic composition and the adhesive layer containing no photochromic compound are not lower than 100° C.

7. The laminate according to claim 5 , wherein the polycarbonate optical sheet or film, the adhesive layer containing no photochromic compound, the adhesive layer of the photochromic composition, the polarizing film layer, the adhesive layer containing no photochromic compound and the polycarbonate optical sheet or film are laminated in this order.

8. The laminate according to claim 7 , wherein the adhesive layer of the photochromic composition described before the polarizing film differs from the adhesive layer containing no photochromic compound described after the polarizing film only in that the former layer contains the photochromic compound.

9. The laminate according to claim 7 , wherein an adhesive layer which differs from the adhesive layer containing no photochromic compound is further existent between the adhesive layer containing no photochromic compound described after the polarizing film layer and the polycarbonate optical sheet or film.

10. The laminate according to claim 1 , wherein at least one optical sheet or film is existent between the polarizing film layer and the adhesive layer of the photochromic composition.

11. The laminate according to claim 1 , wherein a cellulose triacetate film is laminated on both sides of the polarizing film layer.

12. The laminate according to claim 1 , wherein the softening point of the adhesive layer of the photochromic composition is not lower than 100° C.

13. An optical article manufactured by laminating a polycarbonate layer on the front surface of a polycarbonate optical sheet or film on the polarizing film layer side of the laminate of claim 1 .