Selective absorber on glass and method for its production

Claim 1

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of black nickel over the layer of silver by preparing a black nickel plating solution, bringing the plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the plating solution, and applying electrical potential between the layer of deposited silver and an anode submerged in the black nickel plating solution until the layer of black nickel has achieved a thickness of between 0.02 and 0.5 microns; and (d) heat treating said glass substrate and composite layer of silver and black nickel in a vacuum of about 20 microns or less and a temperature of about 200 to 600 degrees centigrade for about 2 to 24 hours.

Claim 2

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of black nickel over the layer of silver by preparing a black nickel plating solution, bringing the plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the plating solution, and applying electrical potential between the layer of deposited silver and an anode submerged in the black nickel plating solution until the layer of black nickel has achieved a thickness of between 0.02 and 0.5 microns; and (d) heat treating said glass substrate and composite layer of silver and black nickel in a vacuum of about 20 microns or less and a temperature of about 200 to 600 degrees centigrade for about 2 to 24 hours.

Claim 5

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of cobalt nickel over the layer of silver by preparing a cobalt nickel plating solution, bringing the cobalt nickel plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the cobalt nickel plating solution, and applying electrical potential between the layer of deposited silver and an anode submerged in the cobalt nickel plating solution until the layer of cobalt nickel has achieved a thickness of between 0.02 and 0.5 microns, (d) electroplating a layer of iron over the layer of cobalt nickel by preparing an iron plating solution, bringing the iron plating solution to a temperature between 20 and 53 degrees centigrade, submerging the glass substrate with the deposited layer of silver and electroplated layer of cobalt nickel into the iron plating solution and applying an electrical potential between the layer of plated cobalt nickel and an anode submerged in the iron plating solution until the layer of iron has achieved a thickness of between 0.20 and 0.5 microns; and (e) heat treating the glass substrate and composite silver, cobalt nickel and iron layers in air at about one atmosphere and a temperature of about 200 to 400 degrees centigrade for about 10 minutes to 24 hours.

Claim 6

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of cobalt nickel over the layer of silver by preparing a cobalt nickel plating solution, bringing the cobalt nickel plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the cobalt nickel plating solution, and applying electrical potential between the layer of deposited silver and an anode submerged in the cobalt nickel plating solution until the layer of cobalt nickel has achieved a thickness of between 0.02 and 0.5 microns, (d) electroplating a layer of iron over the layer of cobalt nickel by preparing an iron plating solution, bringing the iron plating solution to a temperature between 20 and 53 degrees centigrade, submerging the glass substrate with the deposited layer of silver and electroplated layer of cobalt nickel into the iron plating solution and applying an electrical potential between the layer of plated cobalt nickel and an anode submerged in the iron plating solution until the layer of iron has achieved a thickness of between 0.20 and 0.5 microns; and (e) heat treating the glass substrate and composite silver, cobalt nickel and iron layers in air at about one atmosphere and a temperature of about 200 to 400 degrees centigrade for about 10 minutes to 24 hours.

Claim 8

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of nickel over the layer of silver by preparing a nickel plating solution bringing the nickel plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the nickel plating solution, and applying electrical potential between the layer of deposted silver and an anode submerged in the nickel plating solution until the layer of nickel has achieved a thickness of between 0.02 and 0.5 microns; (d) electroplating a layer of iron over the layer of nickel by preparing an iron plating solution, bringing the iron plating solution of between 20 and 53 degrees centigrade, submerging the glass substrate with the desposited layer of silver and electroplated layer of nickel into the iron plating solution and applying electrical potential between the layer of plated nickel and an anode submerged in the iron plating solution until the layer of iron has achieved a thickness of between 0.02 and 0.5 microns; and (e) heat treating the glass substrate and composite silver, nickel and iron layers in air at about one atmosphere and a temperature of about 200 to 400 degrees centigrade for about 10 minutes to 24 hours.

Claim 9

A method for producing a composite layer on a glass substrate for selectively absorbing solar radiation, the composite layer and glass substrate having a coefficient of solar absorption greater than 0.70 and an infrared emittance less than 0.20, comprising the steps of: (a) cleaning the glass substrate; (b) chemically depositing a layer of silver metal on the glass substrate by exposing the glass substrate to simultaneous sprays of a silvering solution and a reducing solution until said layer of silver metal achieves a thickness on the order of 0.10 microns; (c) electroplating a layer of nickel over the layer of silver by preparing a nickel plating solution bringing the nickel plating solution to a temperature of between 20 and 53 degrees centigrade, submerging the glass substrate with the layer of chemically deposited silver into the nickel plating solution, and applying electrical potential between the layer of deposted silver and an anode submerged in the nickel plating solution until the layer of nickel has achieved a thickness of between 0.02 and 0.5 microns; (d) electroplating a layer of iron over the layer of nickel by preparing an iron plating solution, bringing the iron plating solution of between 20 and 53 degrees centigrade, submerging the glass substrate with the desposited layer of silver and electroplated layer of nickel into the iron plating solution and applying electrical potential between the layer of plated nickel and an anode submerged in the iron plating solution until the layer of iron has achieved a thickness of between 0.02 and 0.5 microns; and (e) heat treating the glass substrate and composite silver, nickel and iron layers in air at about one atmosphere and a temperature of about 200 to 400 degrees centigrade for about 10 minutes to 24 hours.