Infrared absorbing compositions and laminates
View Patent ↗Laminates are disclosed having interlayers containing an infrared absorbing amount of lanthanum hexaboride (LaB 6 ) coated on or dispersed in a thermoplastic polymeric matrix. Preferably, the LaB 6 is combined with other materials, such as indium tin oxide, antimony tin oxide, organic dyes or pigments in a polymeric matrix of polyvinyl butyral (PVB). Alternatively, LaB 6 is coated on a sheet of polyethylene terephthalate and encapsulated with one or more sheets of PVB. The interlayers having LaB 6 dispersed therein or coated thereon are advantageously combined with encapsulation layers, reflective layers, dyed layers and/or pigmented layers.
1. A laminate transparent to visible light and absorbing light in the infrared region of the spectrum, comprising
at least one substrate;
a reflective film; and
an absorbing sheet having an infrared absorbing amount of lanthanum hexaboride nanoparticles dispersed in a thermoplastic polymeric matrix.
2. The laminate of claim 1 , wherein said reflective film comprises a sheet of metallized polyethylene terephthalate.
3. The laminate of claim 1 , wherein said reflective film comprises a multi-layer spectrally selective film.
4. The laminate of claim 1 , wherein said absorbing sheet further comprises spectrally selective infrared absorbing organic dyes or pigments dispersed in said thermoplastic polymeric matrix.
5. The laminate of claim 1 , further comprising an additional thermoplastic polymeric layer having organic dye or pigment dispersed therein.
6. The laminate of claim 1 , wherein said absorbing sheet further comprises indium tin oxide nanoparticles, antimony tin oxide nanoparticles, or mixtures thereof, dispersed in said thermoplastic polymeric matrix.
7. The laminate of claim 1 , comprising two rigid substrates transparent to visible light, wherein said reflective film and absorbing sheet are interposed between the two rigid substrates.
8. The laminate of claim 1 , wherein said thermoplastic polymeric matrix is polyvinyl butyral and said lanthanum hexaboride nanoparticles have an average size in the range 5 to 200 nm.
9. The laminate of claim 1 , further comprising a polyethylene terephthalate film coated with particles selected from the group consisting of lanthanum hexaboride particles, indium tin oxide particles, antimony tin oxide particles, and mixtures thereof.
10. A laminate transparent to visible light and absorbing light in the infrared region of the spectrum comprising:
a polymer sheet having a coating of lanthanum hexaboride nanoparticles;
at least one encapsulating layer of thermoplastic polymeric material encapsulating said coated sheet; and
at least one substrate.
11. The laminate claim 10 , wherein said polymer sheet is a polyethylene terephthalate sheet coated with a mixture of lanthanum hexaboride with at least one of indium tin oxide and antimony tin oxide, said at least one encapsulating layer is a polyvinyl butyral encapsulating layer and said polymer sheet and encapsulating layer are interposed between two glass substrates.
12. The laminate of claim 10 , wherein said encapsulating layer includes a dispersed organic dye or a dispersed pigment.
13. The laminate of claim 10 , further comprising a reflective film.
14. A multilayer structure transparent to visible light and absorbing light in the infrared region of the spectrum, comprising:
a thermoplastic polymeric layer having lanthanum hexaboride nanoparticles dispersed therein or coated thereon; and
at least one additional polymeric layer adjacent said thermoplastic polymeric layer.
15. The multilayer structure of claim 14 , wherein
said thermoplastic polymeric layer is a layer of polyvinyl butyral having lanthanum hexaboride particles dispersed therein, and
said additional polymeric layer is a reflective film of embossed metallized polyethylene terephthalate.
16. The multilayer structure of claim 14 , wherein
said thermoplastic polymeric layer is a layer of polyethylene terephthalate coated with lanthanum hexaboride nanoparticles and at least one of indium tin oxide and antimony tin oxide, and
said at least one additional polymeric layer comprises a polyvinyl butyral encapsulating layer.
17. The multilayer structure of claim 15 , wherein said thermoplastic polymeric layer has dispersed therein, indium tin oxide, antimony tin oxide or a mixture thereof.
18. The multilayer structure of claim 16 , wherein said additional polymeric layer comprises an organic dye or pigment.
19. The multilayer structure of claim 16 , wherein said at least one additional polymeric layer comprises two layers of polyvinyl butyral encapsulating said coated layer of polyethylene terephthalate.
20. An infrared-absorbing visible light transparent composition in sheet form comprising:
a polymeric matrix material;
nanoparticulate lanthanum hexaboride dispersed in the polymeric matrix material; and
at least one organic dye or pigment that absorbs light in the visible or near infrared region of the spectrum dispersed in the polymeric matrix material.
21. The infrared-absorbing visible light transparent composition in sheet form according to claim 20 ,
wherein the polymeric matrix material comprises polyvinyl butyral and the
nanoparticulate lanthanum hexaboride has an average particle size in the range of 5 to 200 nm and is present in an amount between 0.001 and 0.1 percent by weight of said polymeric matrix material; and wherein the infrared-absorbing visible light transparent composition further comprises
antimony tin oxide, indium tin oxide or a mixture thereof present in an amount between 0.05 and 2.0 percent by weight of the composition; and
a light attenuating effective amount of pigment or organic dye.