Abstract:
The invention relates to high Tg monolithic and multi-layer thermoformable film or sheet useful as a backsheet on a photovoltaic module (PV). A methacrylic-based material is preferred. The film or sheet is formed of a composition having a Tg greater than 110° C. The methacrylic composition may be a blend of a polymethyl methacrylate polymer and a miscible or semi-miscible high Tg polymer, or may be a copolymer containing primarily methyl methacrylate monomer units. The backsheet is optionally covered with a fluoropolymer or acrylic/fiuoropolymer covering on the outside (side facing the environment). The back-sheet can be clear, white, and/or pigmented. The film or sheet is especially useful in concentrating photovoltaic modules (CPV), and is also useful in thin film photovoltaic modules.
Abstract:
The invention relates to a photovoltaic module for capturing and using solar radiation having as a backsheet a composition containing polyvinylidene fluoride. The polyvinylidene fluoride backsheet layer is exposed to the environment and provides chemical resistance, low water vapor transmission, electrical insulation, and UV light protection.
Abstract:
The invention relates to the use of an impact-modified acrylic blend with a low level of fluoropolymer to achieve impact resistance and solvent resistance in a capstock formulation. Preferably the acrylic blend contains a methyl methacrylate-based acrylic polymer and polyvinylidene fluoride.
Abstract:
A surface modified, U.V. stabilized opaque polyvinyl chloride resin article and process for making same is described. The article includes a white pigment, such as titanium dioxide, in low amounts. The modified surface is substantially free of residual stabilizer and solvent, and its appearance and degree of surface perfection is substantially the same as an unmodified side of the article.The process of the invention is characterized by the steps of immersing the polyvinyl chloride article is immersed in a suitable liquid media, then contacted with a solution of an ultraviolet light stabilizer in a suitable organic solvent, and residual stabilizer and solvent are displaced in situ, i.e. in a non-evaporative environment without contacting the air.
Abstract:
A surface modified U.V. stabilized article is described which includes a resinous sheet whose sides are both exposed to the air. The surface regions of both sides of the sheet are substantially fully modified in situ with a stabilizing amount of an ingredient such as an ultraviolet light stabilizer material, while the exposed surfaces are substantially free of residual stabilizer and solvent material. The appearance and degree of surface perfection of the modified sides of the sheet are substantially the same as that of an untreated sheet. The U.V. stabilized resin article is made by a continuous process in which the resin body is immersed in a solution of an ultraviolet light stabilizer in a suitable organic solvent, and thereafter, residual stabilizer and solvent are displaced from the modified surfaces in situ. Both steps in the process are carried out in an environment which is non-evaporative of the solvent.
Abstract:
An improvement in the process of incorporating a modifier ingredient into the surface region of a resinous article is described herein. The basic process includes immersing the article in a liquid such as water and contacting the immersed article with a solution of a modifier ingredient in a solvent which is immiscible with the liquid. The improvement herein comprises running the process at a temperature lower than ambient or room temperature whereat substantially no solid material is formed on the surface of the water layer during the process.
Abstract:
What is described herein is a process of making a U.V. stabilized PVC article wherein the surface region of the article is modified with a U.V. stabilizer and the treated surface is substantially free of residual stabilizer thereon. The process includes the steps of (a) applying a solution of a U.V. stabilizer in a solvent which is capable of swelling the PVC but is otherwise non-aggressive thereto, and (b) displacing residual solution remaining on said thus treated surface by a liquid which is non-miscible with said solvent.In the preferred form of the invention, step (b) is carried out by contacting the treated surface with water to cause physical removal of the residual solution out of its position on the treated surface, such as by agitation, a jet stream, ultrasonics, and the like.
Abstract:
The invention relates to a thin, nano-structured coating that provides optical light efficiency enhancement. The dried coating contains nano-structures that provide a very low haze level of less than 2 percent, and a light transmission improvement of at least 1% over the non-coated substrate. For the nano-structured coating on an acrylic substrate the transmission is greater than 93 percent, and preferably greater than 94 percent. The coatings of the invention are especially useful for optical electronic displays and photovoltaic modules.
Abstract:
The invention relates to high efficiency diffusion lighting coverings useful in LED lighting applications. The diffusing lighting coverings are made of organic diffusing particles homogeneously dispersed in a transparent polymer matrix. The primary organic diffusing particles are refractive index mis-matched to the matrix polymer. The refractive index contrast between the polymer matrix and diffusion particles, and particle size are selected to provide a high efficiency (minimized particle loading). The high efficiency diffusion coverings provides excellent light diffusion, high hiding properties and high light transmission. The secondary diffusion particles may optionally be added to further improve selected target properties of the covering. Nano-sized ZnO inorganic particles may also function as diffusion particles and optical brighteners as well UV stabilizers. Articles made of this translucent composition are useful in commercial and residential lighting, motor vehicle illumination (lights, panels), street lighting, displays and signs, desktop monitors, and LCD/LED TVs.
Abstract:
The invention relates to optical light diffusers for use with point light sources, such as LED lighting. The optical diffusers achieve an optimum balance of light transmission and hiding power. The optical light diffuser is a transparent plastic matrix, such as Plexiglas® resin from Arkema Inc., having organic particles dispersed within the matrix. The particles are crosslinked beads having specific particle sizes and loading. Different beads can be combined to provide added properties such as a textured surface, and to optimize hiding power and light transmission. The invention also relates to a luminous device containing at least one light-emitting diode and a cover made of the optical light diffuser. The invention further relates to a method for assessing hiding power.