Patent ID: 8722831

Claim:
A cross copolymer, comprising an olefin/aromatic vinyl compound/aromatic polyene copolymer cross polymerized with an anionically polymerizable vinyl compound monomer, wherein the cross copolymer contains 40 mass % to 90 mass %, based on the mass of the cross copolymer, of the olefin/aromatic vinyl compound/aromatic polyene copolymer, the olefin/aromatic vinyl compound/aromatic polyene copolymer has an aromatic vinyl compound unit content of from 15 mol % to 40 mol %, an aromatic polyene unit content of from 0.01 mol % to 3 mol % and the remainder composed of olefin units, the olefin/aromatic vinyl compound/aromatic polyene copolymer has a weight average molecular weight of from 30,000 to 150,000, the cross copolymer is transparent and a sheet of the cross polymer having a thickness of 1 mm has a haze of at most 25% and has a total light transmittance of at least 75%, and the cross copolymer has a type A hardness of from 50 to 85.