| 摘要 |
PURPOSE:To reduce the deterioration of the surface at transfer and reproduction, by providing a copper or copper alloy on the surface, in a master and a mother such as video disc. CONSTITUTION:On the surface of a recording mother disc consisting of a glass plate 1 and a residual resist film 2, copper or copper alloy having 200-5,000Angstrom thickness is stuck by vapor deposition or sputtering. Next, a copper layer 9 is electrically deposited as far as >=2mu by the electrotyping method and nickel 10 is formed thereon in several hundreds mu thickness. After the master 10 having the copper surface layer 9 is peeled off with immersion to potassium dichromate solution, a copper 11 is electrodeposited further on the surface layer 9. The backing 12 is made with nickel electrotyping for peeling, allowing to form a mother 12 with a copper surface layer 11. |
