| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical information recording medium for surely preventing warp caused by change in temperature or humidity even when thin film layers including a recording film are formed of two or more layers. <P>SOLUTION: The optical information recording medium 10a is provided sequentially with a first thin film layer 40a including a recording film 42a, a first resin layer 50a, a second thin film layer 60a including a recording film 62a, and a second resin layer 70a formed on a substrate 20a. A coefficient of linear expansion and a coefficient of humidity expansion of the first resin layer 50a are selected to set a neutral plane of deformation generated by temperature change in the second thin film layer 60a as the thin film layer including a thin film providing the largest product value of the Young's modulus of film material and the film thickness among the thin film layers. In the structure explained above, change in warpage becomes very small when temperature is changed and when humidity is changed. <P>COPYRIGHT: (C)2010,JPO&INPIT |
