# US 2015/0144191 A1 · Polymer sheet > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2015/0144191 A1 - Document ID: US20150144191A1 - Status: Published application - Kind: A1 - Application number: 14/400,900 - Filed: 2013-05-15 - Published: 2015-05-28 - Earliest claimed: 2012-05-16 - Assignees: Novopolymers N.V. - Applicants: Novopolymers N.V - Inventors: Johan Willy Declerck; Koen Hasaers; Kristof Proost - Web page: https://patentgrep.com/patent/US20150144191A1 ## CPC - H10F 77/45: Wavelength conversion means, e.g. by using luminescent material, fluorescent concentrators or up-conversion arrangements - B32B 17/10018: {comprising only one glass sheet} - B32B 17/10669: {Luminescent agents} - B32B 17/10697: {being cross-linked} - B32B 17/10788: {containing ethylene vinylacetate} - B32B 27/08: of synthetic resin - B32B 27/20: using fillers, pigments, thixotroping agents - B32B 27/306: {comprising vinyl acetate or vinyl alcohol (co)polymers} - B32B 27/32: comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} - H10F 19/80: Encapsulations or containers for integrated devices, or assemblies of multiple devices, having photovoltaic cells - H10F 19/804: {Materials of encapsulations} - H10F 19/807: {Double-glass encapsulation, e.g. photovoltaic cells arranged between front and rear glass sheets} - H10F 19/85: Protective back sheets - Y02E 10/52: PV systems with concentrators - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract The invention is directed to a polymer sheet and its use as part of a solar paneland glass element. The sheet comprises multiple coextruded polymer layers, wherein at least two or more layers of the polymer sheet comprise a luminescence downshifting compound for at least partially absorbing radiation having a certain wavelength and re-emitting radiation at a longer wavelength than the wavelength of the absorbed radiation, and wherein a luminescence downshifting compound in a first polymer layer can absorb more radiation at a lower wavelength than the luminescence downshifting compound present in a next layer. ## Claims ### Claim at position 1 -45. (canceled) ### Claim 46 A polymer sheet comprising multiple coextruded polymer layers, wherein at least one of these layers comprises a luminescence downshifting compound for at least partially absorbing radiation having a certain wavelength and re-emitting radiation at a longer wavelength than the wavelength of the absorbed radiation, and wherein the sheet comprises two outer polymer layers and at least one inner polymer layer, wherein an outer polymer layer or both outer polymer layers have a melting point T1 which is at least 10° C. below the melting point T2 of at least one inner polymer layer, and wherein the polymer sheet is obtained by co-extrusion of different polymer materials, which polymer materials are extruded at an extrusion temperature for each sub-layer so chosen that the largest difference in melt flow index of the polymers of the sub-layers at the extrusion temperature as applied for each sub-layer is lower than 3 MFI points. ### Claim 47 (depends on 46) The polymer sheet of claim 46, wherein two or more layers of the polymer sheet comprise a luminescence downshifting compound. ### Claim 48 (depends on 47) The polymer sheet of claim 47, wherein a first polymer layer comprises a luminescence downshifting compound for at least partially absorbing UV radiation and re-emitting radiation at a higher wavelength. ### Claim 49 (depends on 48) The polymer sheet of claim 48, comprising at least two coextruded polymer layers and wherein the one or more different luminescence downshifting compounds present in the first layer will absorb radiation at a lower wavelength than the one or more different luminescence downshifting compounds present in a next layer. ### Claim 50 (depends on 46) The polymer sheet of claim 46, wherein at least one of the polymer layers comprises ethylene vinyl acetate (EVA), ethylene vinyl alcohol (EVOH), polyvinylbutyral (PVB), polymethylmethacrylate(PMMA), alkylmethacrylate, alkylacrylate copolymers, polyurethanes, functionalized polyolefines, ionomers, thermoplastic polydimethylsiloxane copolymers, or mixtures thereof. ### Claim 51 (depends on 46) The polymer sheet of claim 46, wherein at least one of the polymer layers has high moisture and/or gas barrier properties. ### Claim 52 (depends on 46) The polymer sheet of claim 46, wherein at least one of the outer polymer layers comprises a silane coupling agent. ### Claim 53 (depends on 46) The polymer sheet of claim 46, wherein the inner polymer layer comprises an optionally hydrogenated polystyrene block copolymer with butadiene, isoprene and/or butylenes/ethylene copolymers (SIS, SBS and/or SEBS); a ethylene vinyl alcohol (EVOH) copolymer, a polymethacrylate polyacrylate block copolymer, a polyolefin, a polyolefine copolymer or terpolymer, or an olefin copolymer or terpolymer, with copolymerizable functionalised monomers such as methacyrylic acid (ionomer). ### Claim 54 (depends on 50) The polymer sheet of claim 50, wherein the ethylene vinyl acetate has an acetate content of more than 18% by weight. ### Claim at position 11 -65. (canceled) ### Claim 66 (depends on 46) A glass element comprising two layers of glass, wherein a transparent polymer layer is present between the two layers of glass and wherein the polymer layer comprises a polymer sheet of claim 46. ### Claim 67 (depends on 66) The glass element of claim 66, wherein the total thickness of the glass element is less than 5 mm. ### Claim 68 (depends on 66) The glass element of claim 66, wherein at least one of the glass layers has a thickness of between 0.1 and 2 mm. ### Claim 69 (depends on 66) The glass element of claim 66, wherein at least one glass layer has a surface not facing the polymer layer which is covered with an anti-reflective coating. ### Claim 70 (depends on 66) The glass element of claim 66, wherein at least one glass layer has an embossed surface not facing the polymer layer. ### Claim 71 (depends on 66) A photovoltaic module comprising a layer comprising: (a) a photovoltaic cell, and (b) a cover layer comprising the glass element of claim 66. ### Claim 72 (depends on 66) A CdTe photovoltaic solar cell comprising the glass element of claim 66, wherein the glass element further comprises (a) a transparent electrode layer, (b) an n-type semiconductor layer, (c) a cadmium telluride absorber layer and (d) a back contact. ### Claim 73 (depends on 46) A solar panel comprising: (a) a polymer sheet of claim 46, and (b) a photovoltaic cell. ### Claim 74 (depends on 73) The solar panel of claim 73, wherein the glass layer facing the incoming radiation is provided with an anti-reflective coating. ### Claim 75 A process of making a solar panel by subjecting a stack to a thermal lamination at an elevated lamination temperature, wherein the stack comprises the following layers: (a) a first glass layer, (b) a polymer sheet of claim, (c) a layer comprising a photovoltaic cell, (d) a polymer encapsulant layer; and (e) a second glass layer. ### Claim 76 (depends on 75) The process of claim 75,wherein the polymer sheet (b) is comprised of 3 or more multiple coextruded thermoplastic polymer sub-layers comprising two outer sub-layers and at least one inner sub-layer, wherein the polymer sheet (b) is obtained by co-extrusion of different polymer materials which polymer materials are extruded at an extrusion temperature for each sub-layer chosen so that the largest difference in melt flow index of the polymers of the sub-layers at the extrusion temperature as applied for each sub-layer is lower than 5 MFI points, wherein the lamination temperature TL is higher than the extrusion temperature TC of an inner sub-layer; and wherein the temperature TC is higher than the extrusion temperature TA of an outer sub-layer and/or TB of the other outer sub-layer.