Preparation method of light conversion powder protection structure and photovoltaic adhesive film

Abstract

The invention provides a preparation method of a light conversion powder protection structure and a photovoltaic adhesive film, the light conversion powder is formed by a benzotriazole derivative, and the protection structure is formed by at least one layer of organic polymer outside the light conversion powder to protect the light conversion powder. Therefore, the light conversion powder is prevented from being damaged by peroxide in the adhesive film after being placed in the adhesive film.

Description

Technical Field

[0001] The invention relates to a method for preparing a specific organic light-converting powder, and a photovoltaic adhesive film containing the specific light-converting powder inside. Background Art

[0002] In order to convert natural sunlight from the sun into visible light acceptable to solar cells, light conversion materials are usually added to the film of solar panels. The light conversion materials have the ability to convert ultraviolet light from sunlight into visible light to enhance the light-to-electricity conversion effect of solar cells.

[0003] It is a well-known fact that after the photovoltaic film is attached to the solar cell, the main function of the photovoltaic film is to provide a stable and reliable environment for the solar cell to continue to work; and in order to enhance the function of the photovoltaic film, some functions are generally preset inside the photovoltaic film, such as pre-crosslinking, or some additives are added to enhance the performance of the photovoltaic film, such as adhesion, water barrier, etc. Among these added additives, there are often substances that can cause damage to the photoconversion powder, such as crosslinking agents such as peroxide. After the peroxide is added to the photovoltaic film, the performance of the film is increased, but the photoconversion powder added to the film as the most direct assistant for photoelectric conversion will be damaged by the addition of peroxide, so that the preset photoelectric conversion efficiency and performance cannot be achieved.

[0004] Therefore, in order to maintain the original effect of the light conversion powder in converting ultraviolet light into visible light and to prevent the light conversion powder from being damaged by peroxides in the film, it is imperative to protect the light conversion powder so that the photovoltaic cell can exert its original photoelectric conversion efficiency as expected. In order to achieve the above purpose, the present invention proposes a method for preparing a protective structure of a specific light conversion powder. Summary of the invention

[0005] In order to provide a method for preparing a protective structure of a light-converting powder and improve the efficiency of photoelectric conversion of photovoltaic modules, the present invention adopts the following technical solutions:

[0006] The main purpose of the present invention is to provide a method for preparing a light-converting powder protective structure, which is characterized by comprising:

[0007] Preparing a light-converting powder formed from a benzotriazole derivative;

[0008] Selecting a suitable organic polymer monomer;

[0009] Dissolving the organic light-converting powder in the organic polymer monomer to obtain a solution;

[0010] dispersing the solution with a dispersant; and

[0011] The first solution is polymerized to obtain an organic light conversion powder, the outer surface of which is coated with at least one layer of organic polymer.

[0012] Another object of the present invention is that the organic polymer monomer is selected from one of polyvinyl chloride, polymethyl methacrylate, polyvinyl acetate, cellulose acetate, polyamide, polyimide, polycarbonate, polystyrene, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl alcohol, transparent ABS plastic, polyacrylonitrile, polyolefin elastomer, thermoplastic polyurethane, polyvinyl carbazole, polycycloolefin or a mixture thereof.

[0013] Another object of the present invention is that the organic polymer is two layers.

[0014] Another object of the present invention is that the thickness of the organic polymer ranges from 100 nanometers to 500 micrometers.

[0015] The difference between the refractive index of the organic polymer and the refractive index of the converted light is between 0 and 0.2.

[0016] Another object of the present invention is that when dispersing the solution, the dispersant selected includes polyvinyl alcohol (PVA).

[0017] Another object of the present invention is that the polymerization step includes raising the temperature to 95 degrees Celsius.

[0018] Another object of the present invention is that the polymerization step includes an initiator for initiating the polymerization, and the initiator includes a peroxide initiator and an azo initiator.

[0019] Another object of the present invention is to provide an adhesive film including a light-converting powder having a protective structure. DETAILED DESCRIPTION

[0020] In order to make the invention purpose, technical scheme and beneficial technical effect of the present invention clearer, the present invention is described in detail below in conjunction with specific embodiments. It should be understood that the embodiments described in this specification are only for explaining the present invention, not for limiting the present invention.

[0021] For simplicity, only some numerical ranges are explicitly disclosed herein. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, and any upper limit can be combined with any other upper limit to form an unspecified range. In addition, although not explicitly stated, each point or single value between the endpoints of the range is included in the range. Therefore, each point or single value can be combined as its own lower limit or upper limit with any other point or single value or with other lower limits or upper limits to form an unspecified range.

[0022] In the description of this article, it should be noted that, unless otherwise specified, "above" and "below" are inclusive of the number, and the "multiple" in "one or more" means more than two.

[0023] The above summary of the invention of the present invention is not intended to describe every disclosed embodiment or every implementation in the present invention. The following description more specifically illustrates exemplary embodiments. In many places throughout the application, guidance is provided by a series of examples, which can be used in various combinations. In each example, the enumeration is only a representative group and should not be interpreted as exhaustive.

[0024] Embodiment:

[0025] When implementing the present invention, a certain amount of organic light-converting powder formed by benzotriazole derivatives, for example, 1 g, is first taken, and then a certain amount of initiator of dibenzoyl peroxide (BPO) is taken and dissolved in 10 g of polymethyl methacrylate (MMA) to obtain a first solution. The initiator can be a peroxide initiator or an azo initiator.

[0026] Then, some emulsifier, such as sodium dodecyl sulfate (SDS), for example, 0.2 g, is taken, and another emulsifier (or dispersant), such as 100 g of 0.5 wt % aqueous solution of polyvinyl alcohol (PVA) is added and completely dissolved to obtain a second solution.

[0027] The first solution and the second solution are placed in a container, and the first solution and the second solution are fully mixed at an ambient temperature of 25°C, for example, mechanically stirred at 1500 rpm for 30 minutes (fully dispersed), and then the temperature is raised to 85°C to perform a polymerization reaction. Thereafter, the temperature can be selectively raised to 90°C and maintained for 30 minutes to ensure the polymerization effect.

[0028] The mixture was then centrifuged at high speed (filtering) and washed with deionized water (pure water) three times, and the obtained solid was placed in a vacuum drying oven at 45° C. and dried for 24 hours to obtain a light-converting powder coated with a layer of organic polymer.

[0029] With the above manufacturing method, a protective layer of an organic polymer can be formed on the outside of an organic light-converting powder formed by, for example, a benzotriazole derivative; and of course, after having one layer, the above steps can be repeated to form two or more layers of protective structures on the outside of the light-converting powder as needed.

[0030] The light-converting powder is an organic light-converting powder of a benzotriazole derivative, and its outer organic polymer is an organic polymer protective layer formed by one or a mixture of polyvinyl chloride, polymethyl methacrylate, polyvinyl acetate, cellulose acetate, polyamide, polyimide, polycarbonate, polystyrene, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl alcohol, transparent ABS plastic, polyacrylonitrile, polyolefin elastomer, thermoplastic polyurethane, polyvinyl carbazole, polycycloolefin. The particle size D50 of the light-converting agent is 10 to 20 microns, and its refractive index is about 1.5 to 1.6; and the organic polymer coated on the outside of the light-converting powder to form a layer of coating protection has a thickness of 100 nanometers to 500 microns, and its refractive index is between 1.3 and 1.7. In the refractive index range of organic polymers, it is easy to find a polymer of benzotriazole derivatives with a refractive index of 1.5 to 1.6 in organic polymers, so as to form an organic protective layer that effectively protects the light-converting powder and blocks the external light to the minimum. According to experiments, the difference in refractive index between the two is consistent (the difference is 0), and the second is between 0 and 0.2. At the same time, because of the mutual adaptation of the refractive index, the external light can directly contact the light-converting powder after penetrating the external protective layer, so that the light-converting powder can exert the maximum photoelectric conversion efficiency without losing any light.

Claims

1. A method for preparing a light-converting powder protective structure, characterized in that ,include: Preparing a light-converting powder formed from a benzotriazole derivative; Selecting a suitable organic polymer monomer; Dissolving the organic light-converting powder in the organic polymer monomer to obtain a solution; dispersing the solution with a dispersant; The first solution is polymerized to obtain an organic light conversion powder, the outer surface of which is coated with at least one layer of organic polymer.

2. The method for preparing the light conversion powder protection structure according to claim 1, characterized in that: The organic polymer monomer is selected from polyvinyl chloride, polymethyl methacrylate, polyvinyl acetate, cellulose acetate, polyamide, polyimide, polycarbonate, polystyrene, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl alcohol, transparent ABS plastic, polyacrylonitrile, polyolefin elastomer, thermoplastic polyurethane, polyvinyl carbazole, polycycloolefin or a mixture thereof.

3. The method for preparing the light conversion powder protection structure according to claim 1, characterized in that: The organic polymer is two layers.

4. The method for preparing the light conversion powder protection structure according to claim 1 or 2, characterized in that: The thickness of the organic polymer ranges from 100 nanometers to 500 micrometers.

5. The method for preparing the light conversion powder protection structure according to claim 4, characterized in that: The difference between the refractive index of the organic polymer and the refractive index of the converted light is between 0 and 0.

2.

6. The method for preparing the light conversion powder protection structure according to claim 5, characterized in that: When dispersing the solution, the selected dispersant includes polyvinyl alcohol (PVA).

7. The method for preparing the light conversion powder protection structure according to claim 6, characterized in that: The polymerization step includes raising the temperature to 95 degrees Celsius.

8. The method for preparing a light conversion powder protection structure according to claim 7, characterized in that: It also includes heating up for 20 to 30 minutes.

9. The method for preparing the light conversion powder protection structure according to claim 1, characterized in that: The polymerization step includes an initiator for initiating polymerization, and the initiator includes a peroxide initiator and an azo initiator.

10. A film, characterized in that The adhesive film contains a light-converting powder protective structure prepared by the method for preparing a light-converting powder protective structure in any one of claims 1 to 8.