Composite cooling film comprising a reflective nonporous organic polymeric layer and a UV-protective layer
A composite cooling film including a reflective nonporous inorganic-particle-filled organic polymeric layer, an ultra-violet-protective layer or layers, and an antisoiling layer.
1. A composite cooling film comprising:
a reflective nonporous inorganic-particle-filled organic polymeric layer that exhibits an average reflectance of electromagnetic radiation of at least 85% over a wavelength range from 400 to 2500 nanometers,
an ultraviolet-protective layer of organic polymeric material that is disposed outwardly of the reflective nonporous inorganic-particle-filled organic polymeric layer;
and,
an antisoiling layer of organic polymeric material, the antisoiling layer being disposed outwardly of the reflective nonporous inorganic-particle-filled organic polymeric layer and comprising an outwardly-facing, exposed antisoiling surface;
wherein the composite cooling film has an average absorbance over the wavelength range 8-13 microns of at least 0.85.
2. The composite cooling film of claim 1 wherein the reflective nonporous inorganic-particle-filled organic polymeric layer is a pre-made inorganic-particle-filled film.
3. The composite cooling film of claim 1 wherein the reflective nonporous inorganic-particle-filled organic polymeric layer is an inorganic-particle-filled painted layer.
4. The composite cooling film of claim 3 wherein the painted layer comprises a binder that is an organic polymeric material chosen from polymethylmethacrylate, co-polymethylmethacrylates, polyurethanes, polyolefins, and fluoropolymers.
5. The composite cooling film of claim 1 wherein the inorganic particles are chosen from the group consisting of titania, alumina, calcium carbonate, zinc oxide, barium sulfate, and kaolin clay.
6. The composite cooling film of any of claim 1 wherein the ultraviolet-protective layer of organic polymeric material comprises an ultraviolet-reflective layer.
7. The composite cooling film of claim 6 wherein the ultraviolet-reflective layer comprises a multilayer optical film.
8. The composite cooling film of claim 1 wherein the ultraviolet-protective layer of organic polymeric material comprises an ultraviolet-absorbing layer.
9. The composite cooling film of claim 1 wherein the composite cooling film further comprises a layer of pressure-sensitive adhesive disposed inwardly of the reflective nonporous inorganic-particle-filled organic polymeric layer.
10. The composite cooling film of claim 1 wherein the ultraviolet-protective layer is bonded to the reflective nonporous inorganic-particle-filled organic polymeric layer via a layer of pressure-sensitive adhesive.
11. The composite cooling film of claim 1 wherein the antisoiling layer is bonded to the ultraviolet-protective layer by a layer of pressure-sensitive adhesive.
12. The composite cooling film of claim 1 wherein the ultraviolet-protective layer of organic polymeric material comprises a UV-absorbing layer that is a layer of pressure-sensitive adhesive that is loaded with at least one UV-blocking additive and that is disposed between the reflective nonporous inorganic-particle-filled organic polymeric layer and the antisoiling layer so as to adhesively bond the reflective nonporous inorganic-particle-filled organic polymeric layer and the antisoiling layer to each other.
13. The composite cooling film of claim 1 , wherein the antisoiling layer of organic polymeric material is a fluorinated organic polymeric material.
14. The composite cooling film of claim 1 , wherein the ultraviolet-protective layer of organic polymeric material is an ultraviolet-absorbing layer of organic polymeric material that is the same layer as the antisoiling layer of organic polymeric material.
15. The composite cooling film of claim 1 , wherein the composite cooling film comprises a multilayer structure disposed outwardly of the reflective nonporous inorganic-particle-filled organic polymeric layer; and, wherein an outermost layer of the multilayer structure provides the antisoiling layer of the composite cooling film and another layer of the multilayer structure, which other layer is positioned inwardly of the antisoiling layer, provides a UV-protective layer of the composite cooling film in the form of a UV-absorbing layer.
16. The composite cooling film of claim 15 wherein the multilayer structure is a coextruded structure, wherein the layer of the multilayer structure that provides the antisoiling layer of the composite cooling film comprises a fluorinated polymeric material; and, wherein the other layer of the multilayer structure that provides the UV-absorbing layer of the composite cooling film, comprises a non-fluorinated polymeric material that is loaded with at least one UV-blocking additive.
17. The composite cooling film of claim 1 wherein the outwardly-facing, exposed antisoiling surface of the antisoiling layer is a textured surface comprising micro-structures and/or nano-structures.
18. The composite cooling film of claim 17 , wherein the outwardly-facing, exposed antisoiling surface of the antisoiling layer extends along an axis, and wherein a plane containing the axis defines a cross-section of the antisoiling layer and intersects the surface to define a line describing the surface in two dimensions, the layer comprising:
a series of micro-structures at least partially defined by the line, the line defining a series of alternating micro-peaks and micro-spaces along the axis, wherein each micro-space comprises a maximum absolute slope defining an angle from the axis of at most 30 degrees, wherein each micro-peak comprises a first micro-segment defining a first average slope and a second micro-segment defining a second average slope, and wherein an angle formed between the first and second average slopes is at most 120 degrees; and
a plurality of nano-structures at least partially defined by the line, the line defining at least one series of nano-peaks disposed on at least the micro-spaces along the axis,
wherein each nano-peak has a height and each corresponding micro-peak has a height of at least 10 times the height of the nano-peak.
19. The composite cooling film of claim 18 , wherein the micro-peak first average slope is positive, and the micro-peak second average slope is negative.
20. The composite cooling film of claim 18 , wherein a width of each micro-space is at least one of: at least 10% of a corresponding micro-peak distance or at least 10 micrometers.
21. The composite cooling film of claim 18 , wherein a micro-peak distance between micro-peaks is in a range from 1 micrometer to 1000 micrometers.
22. The composite cooling film of claim 18 , wherein the micro-peaks have a height of at least 10 micrometers.
23. The composite cooling film of claim 18 , wherein the plurality of nano-structures is further disposed on the micro-peaks.
24. The composite cooling film of claim 17 , wherein at least some of the micro-structures and/or nano-structures are provided by inorganic particles present on the outwardly-facing, exposed antisoiling surface.