Patent GB-1043783-A (GB)
Title: Solar energy collector
IPC: F24J2/46
Filed: 1964-03-31
Abstract: A solar energy collector comprises a metallic base such as Ni, stainless steel, Pt, Pd and "Inconel" (Trade Mark), a barrier layer of a refractory such as ceria, alumina, nickel oxide or porcelain enamel and an outer solar energy absorptive receiver layer comprising an intimate fused mixture of gold and glass.  The coating of gold and glass is applied as a liquid gold composition containing an organic gold compound such as gold sulphoresinate or gold mercaptide, inorganic or organic compounds such as resinates chlorides or nitrates of RhBi, CrNi and Co as fluxes and also organic or inorganic compounds which form a glass on firing.  The glass forming compounds are preferably resinates of Si, Ba, Bi and Cr and optionally compounds of Ca, Mg, Be, Li, Sr instead of the Ba and compounds of Ge instead of Si.  The liquid gold composition containing the glass forming compounds is fired at 250 DEG -950 DEG C. to form a coating preferably containing 80-92% gold and 8-20% total oxides such as Bi2O3, CR2O3, SiO2, BaO.  The refractory barrier layer may be applied by any of the following methods:-  (1) Vapour deposition of ceria. (2) Flame spraying of alumina.  (3) Spraying a solution of an organic compound of the metal of the oxide e.g. cerium resinate and firing in air.  (4) Electroplating with nickel and then oxidizing.  (5) Spraying an enamel frit in a liquid vehicle or as a dry powder and firing.  The refractory barrier layer should have a thickness of 200<\>rA-1000<\>rA and the gold glass layer a thickness of 2000<\>rA maximum and preferably 800<\>rA-1800<\>rA.ALSO:A solar energy collector comprises a metallic base such as Ni, stainless steel, Pt, Pd and "Inconel" (Registered Trade Mark), a barrier layer of a refractory such as ceria, alumina, nickel oxide or porcelain enamel and an outer solar energy absorptive receiver layer comprising an intimate fused mixture of gold and glass. The coating of gold and glass is applied as a liquid gold composition containing an organic gold compound such as gold sulphoresinate or gold mercaptide, inorganic or organic compounds such as resinates, chlorides or nitrates of Rh, Bi, Cr, Ni and Co as fluxes and also organic or inorganic compounds which form a glass on firing.  The glass forming compounds are preferably resinates of Si, Ba, Bi and Cr and optionally compounds of Ca, Mg, Be, Li, Sr instead of the Ba and compounds of Ge instead of Si.  The liquid gold composition containing the glass forming compounds is fired at 250 DEG -950 DEG C. to form a coating preferably containing 80-92% gold and 8-20% total oxides such as Bi2O3, Cr2O3, SiO2, BaO.  The refractory barrier layer may be applied by any of the following methods: (1) Vapour deposition of ceria. (2) Flame spraying of alumina. (3) Spraying a solution of an organic compound of the metal of the oxide, e.g. cerium resinate and firing in air. (4) Electroplating with nickel and then oxidising. (5) Spraying an enamel frit in a liquid vehicle or as a dry powder and firing.  The refractory barrier layer should have a thickness of 200 <\>rA-1000 <\>rA and the gold glass layer a thickness of 2000 <\>rA maximum and preferably 800 <\>rA.