HARD COATING FOR GLASS MOLDING AND GLASS MOLDING DIE HAVING THE HARD COATING

Abstract

A hard coating combining excellent mold releasability with respect to glass with excellent durability at high temperature environment of 600° C. or more, and a glass molding die having the hard coating are provided. A glass molding die has a hard coating formed on a molding surface of a base. The hard coating includes one or two of W and V, and B, C and N; wherein when a composition of the coating is expressed as Wa1Va2BbCcNd, 0.1≦a1+a2≦0.5, 0.05≦b≦0.5, 0.02≦c≦0.15, 0.05≦d≦0.5, and a1+a2+b+c+d=1 are given. The hard coating can be formed on the molding surface of the base via an intermediate layer including an amorphous CrSiN film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanatory sectional view of a glass molding die according to a first embodiment of the invention; and

FIG. 2 is an explanatory sectional view of a glass molding die according to a second embodiment of the invention.

Claims

1. A hard coating for glass molding, which is formed on a molding surface of a base of a glass molding die, comprising: one or two of W and V, and B, C and N;wherein when a composition of the coating is expressed as Wa1Va2BbCcNd,0.1≦a1+a2≦0.5, 0.05≦b≦0.5,0.02≦c≦0.15, 0.05≦d≦0.5, anda1+a2+b+c+d=1 are given.

2. The hard coating for glass molding according to claim 1: wherein when a Cu-kα line is used in X-ray diffraction measurement according to a θ-2θ method, half value width of an α-W (110) diffraction line in 20 of 30° to 50° is within a range of 6.0° to 8.0°.

3. A glass molding die having a hard coating formed on a molding surface of a base: wherein the hard coating is formed of the hard coating for glass molding according to claim 1 or 2.

4. The glass molding die according to claim 3: wherein the hard coating preferably has thickness of 100 nm to 3000 nm.

5. The glass molding die according to claim 3: wherein the hard coating is formed on the molding surface of the base via an intermediate layer including an amorphous CrSiN film.

6. The glass molding die according to claim 4: wherein the hard coating is formed on the molding surface of the base via an intermediate layer including an amorphous CrSiN film.