Patent ID: 8555871

Claim:
A radiation-selective absorber coating ( 20 ), in particular for absorber tubes ( 13 ) of parabolic trough collectors ( 10 ), said radiation-selective absorber coating ( 20 ) comprising at least two barrier layers ( 24 a , 24 b ); an infrared reflective layer ( 21 ) that reflects infrared radiation, said infrared reflective layer ( 21 ) being arranged on said at least two barrier layers ( 24 a , 24 b ); at least one absorption layer ( 22 ) arranged above the infrared reflective layer ( 21 ); and an antireflection layer ( 23 ) arranged above the at least one absorption layer ( 22 ); wherein the at least two barrier layers ( 24 a , 24 b )comprise a first barrier layer ( 24 a ) and a second barrier layer ( 24 b ) arranged above the first barrier layer, said first barrier layer consisting of a thermally produced oxide; wherein said second barrier layer ( 24 b ) consists of a cermet material composed of aluminum oxide and molybdenum; and wherein said second barrier layer ( 24 b ) comprises 20 to 70% by volume of said molybdenum.