PURPOSE: To obtain a disk which has excellent durability an is stable for a long period of time by providing a thin film consisting of a mixture composed of specific compds. on the surface of an information recording disk consisting of a PVC resin contg. pulverized particles of a conductive material.

CONSTITUTION: Information signals are recorded in the form of the change of a geometrical shape on the signal surface 2 of the disk 1 which is constituted by using the PVC resin as a base material and contg. at least a prescribed ratio of the pulverized particles of the conductive material. The thin film 3 is then formed on the signal surface 2. The thin film 3 is formed of the mixture composed of the a dimethyl siloxane and the modified polysiloxane expressed by the formula. In the formula, A, B are (CH2)3O(C2H4O)yH, x is 0W30 integer, y is 2W5 integer. The modified polysiloxane has 2.5W10 dielectric constant and is so mixed with the dimethyl siloxane that said siloxane is incorporated at 0.5W2 ratio by weight to dimethyl siloxane.