Patent EP-2737998-A1 (EP)
Inventor: MIKATS GÜNTHER
IPC: B32B27/20
Filed: 2010-11-30
Abstract: The solar module comprises a solar cell (2), which is arranged between a front cover (4) and a rear cover (6), where the front cover enables the passage of light to the solar cell. The rear cover comprises two-layer, halogen-free coextrudate element, which has a first thermoplastic layer (8) facing the solar cell and a second thermoplastic layer (10) facing away from the solar cell. The first thermoplastic layer comprises a first filling material, which has a reflectivity that is higher than the reflectivity of the thermoplastic of the first thermoplastic layer. The solar module comprises a solar cell (2), which is arranged between a front cover (4) and a rear cover (6), where the front cover enables the passage of light to the solar cell. The rear cover comprises two-layer, halogen-free coextrudate element, which has a first thermoplastic layer (8) facing the solar cell and a second thermoplastic layer (10) facing away from the solar cell. The first thermoplastic layer comprises a first filling material, which has a reflectivity that is higher than the reflectivity of the thermoplastic of the first thermoplastic layer, and the second thermoplastic layer comprises a second filling material, which has a higher thermal conductivity than the thermoplastic of the second thermoplastic layer, where in the two thermoplastic layers, the respective fraction of the first or second filling material is different from the fraction of the same filling material in the other thermoplastic layer. The second filling material increases the dielectric strength of the thermoplastic, comprises a lower thermal expansion coefficient than the thermoplastic, is formed in flat or fibrous manner, and consists of mica such as iron mica, wollastonite, boron nitride and/or glass fibers. The first filling material comprises titanium dioxide. A further layer is arranged on the side of the second thermoplastic layer turned away from the solar cell and has lower reflectivity than the surface of the front cover. The further layer has a third thermoplastic layer, which forms the coextrudate body with two another thermoplastic layers. The further layer is dyed and/or comprises matting agent and/or ultra-violet stabilizers. The first thermoplastic layer is dyed such as the total coextrudate element. The solar cell is arranged in an embedding material, which is connected with the first thermoplastic layer and the second thermoplastic layer. The embedding material is a bonding agent between the first thermoplastic layer, the second thermoplastic layer and the solar cell. The bonding agent is a copolymer of the monomer units of olefin such as ethylene, acrylate such as alkyl acrylate and maleic anhydride. The thermoplastic of the first thermoplastic layer, the second thermoplastic layer and if necessary the third thermoplastic layer consists of polyamide, polyester or blends of polyamide and polyolefin. The thermoplastic consists of polyamide 11, polyamide 12, polyamide 1010 or its blends with polyolefin. The content of the first filling material is based on the first thermoplastic layer is 5-30 wt.%, and the content of the second filling material is 5-70 wt.% based on the second thermoplastic layer. Independent claims are included for (1) a coextrudate element; and (2) a facade element.