Glass with scratch-resistant coating
Glass having a diamond-like carbon (DLC) coating on top of an intermediate bonding layer of tin oxide, and a method for producing same. A glow-discharge method is used to apply the DLC coating. The glass may be chemically strengthened prior to applying the DLC coating.
1 . A transparent panel, comprising:
a layer of glass having an air side and a metal-oxide side opposite the air side; and
a layer of diamond-like carbon coating on the metal-oxide side.
2 . A transparent panel as in claim 1 , wherein the metal oxide is tin oxide.
3 . A transparent panel as in claim 2 , wherein the tin-oxide layer is from 20-50 nm in thickness.
4 . A transparent panel as in claim 1 , wherein the glass includes a chemically strengthened region on the metal-oxide side, in which larger atoms have replaced sodium ions of the glass.
5 . A transparent panel as in claim 4 , wherein the chemically strengthened region is from 20-100 microns in thickness.
6 . A method, comprising:
positioning and orienting a glass panel relative to a metallic base plate in a vacuum chamber so as to expose at least a target surface of the glass panel having a layer of tin oxide;
substantially evacuating the chamber;
introducing a hydrocarbon gas into the chamber and applying a pulsed high voltage to the base plate, thereby providing a diamond-like carbon coating of at least a portion of the surface having the layer of tin oxide.
7 . A method as in 6 , wherein the glass is float glass, having a tin-oxide side and an air side.
8 . A method as in claim 6 , further comprising, before placing the glass panel in the vacuum chamber, immersing the glass panel in a molten bath of potassium salt.
9 . A method as in claim 8 , wherein the temperature of the bath is in a range of from 900° F. to 1100° F.
10 . A method as in claim 6 , wherein the pulsed high voltage is in a range of from 1500 volts to 6500 volts.
11 . A method as in claim 6 , wherein the pulse rate is in a range of from 250 Hz to 2250 Hz.
12 . A method as in claim 6 , wherein the feed rate of the hydrocarbon gas is from 10 to 200 standard cubic centimeters per minute.
13 . A method as in claim 6 , wherein the hydrocarbon gas includes acetylene.
14 . A method as in claim 6 , wherein the hydrocarbon gas includes methane.
15 . A method as in claim 6 , wherein the metal oxide is tin oxide.
16 . A method as in claim 15 , wherein the tin-oxide layer is from 20-50 nm in thickness.
17 . A method as in claim 6 , wherein at least two glass panels are coated at the same time, and each is placed on a respective metal base plate, and the metal base plates face each other but are held away from parallel at a tilt angle of approximately at least 10 degrees.
18 . A glass panel having a diamond-like carbon coating, as made according to the method of claim 6 .