Patent ID: 7338695
Filing Date: 2008-03-04
Classification: G01N,G11B

Abstract:
1. An optical information medium comprising: a supporting substrate; an information recording layer on the supporting substrate; a light-transmitting layer on the information recording layer; and a light-transmitting hard coat layer on the light-transmitting layer, wherein the light-transmitting hard coat layer and the light-transmitting hard coat layer has a combined thickness of 70 to 150 μm, wherein the medium is configured to have a recording/reproducing beam incident into the information recording layer through the light-transmitting hard coat layer and the light-transmitting layer, and a surface of the medium which is on a side on which the recording/reproducing beam is incident is configured such that when an evaluation dispersion liquid containing a fine-particle-form substance and a dispersion medium capable of dispersing the fine-particle-form substance is adhered onto the surface of the medium, a structure of the surface of the medium interacts with the evaluation dispersion liquid such that an area ratio of the medium surface occupied with the evaluation dispersion liquid droplets adhered per unit area of the medium surface is 25% or less.