| 摘要 |
PROBLEM TO BE SOLVED: To obtain an optical card having satisfactory adhesive strength between a transparent substrate and a back substrate by setting the breaking elongation of a core material layer to a value not larger than a specific value in an optical card having an adhesive layer consisting of a first adhesive layer, the core material layer and a second adhesive layer. SOLUTION: In an optical card 1, a rear substrate 7 is adhered on an optical recording layer 5 via a multilayer adhesive layer 6a consisting of a first adhesive layer 8, a core material layer 9 and a second adhesive layer 10, and a printing layer 11 for forming visible information is provided outside the rear substrate 7. In this case, for the first and the second adhesive layer, the same adhesive such as adhesion or hot melt type adhesive is used, and vinyle chloride is used for the core material layer 9. Here, the core material layer 9 is of a plate shape and is made of a material having flexibility and hardly causing embosment distortion, that is, a material having a characteristic that the breaking elongation is 200% or less, preferably 100% or less. When the breaking elongation of the core material layer 9 exceeds 200%, distortion on the surrounding of embosment information part of the card subjected to embosment working may become layer. |
