Protective structure of light conversion powder, preparation method of protective structure and photovoltaic adhesive film

Abstract

The invention provides a protection structure of light conversion powder, a preparation method of the protection structure and a photovoltaic adhesive film. The protective structure is formed by at least one layer of organic polymer, and the light conversion powder is also organic light conversion powder, so that an organic-coated organic structure is formed, and good compatibility, light transmission and aging resistance can be formed for the light conversion powder.

Description

Technical Field

[0001] The invention relates to a light conversion powder protection structure, a preparation method thereof, and the application of the light conversion powder in the photovoltaic field. Background Art

[0002] Light conversion materials can convert ultraviolet light into visible light. Currently, light conversion materials are mostly added to the encapsulation film in photovoltaic modules to improve the photoelectric conversion efficiency of solar cells in subsequent processes, especially after being combined with battery modules.

[0003] As mentioned above, solar cells mainly rely on visible light, so the more sunlight, the more electricity they generate. Under the previous question, of course, solar cells that directly receive sunlight can directly generate the required electricity. However, considering that solar cells are directly exposed to various environmental factors such as wind, sun, rain, etc. outdoors, they are very easy to age, and the components in the components will also be damaged to varying degrees due to the influence of water vapor, so the outside of the solar cell will be protected by a packaging film. In order to strengthen the protection of the packaging film for solar cells and enhance the performance of the packaging film, when making the packaging film, light conversion powder, additives or pre-crosslinking are usually added to achieve the purpose of increasing the performance of the packaging film. Little do people know that when adding light conversion powder that can convert ultraviolet light into visible light, the addition of additives such as peroxide crosslinking agents will damage the light conversion powder, so that the effect of ultraviolet light conversion is also affected to a certain extent.

[0004] In order to solve the problem of light-converting powder being damaged in the adhesive film, the present invention introduces a protective structure to protect the light-converting powder in an environment filled with additives that may cause damage to the light-converting powder. Summary of the invention

[0005] In order to provide a light conversion powder which has high compatibility with the basic resin in the photovoltaic film, high light transmittance, good aging resistance, and can improve the efficiency of the photovoltaic module, the present invention adopts the following technical solutions:

[0006] The present invention provides a protective structure for a light-converting powder. The light-converting powder is an organic light-converting powder formed by a benzotriazole derivative. The protective structure is formed outside the light-converting powder and can form at least one layer of organic polymer covering the light-converting powder.

[0007] Another object of the present invention is that the organic polymer 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.

[0008] Another object of the present invention is that the organic polymer is two layers.

[0009] Another object of the present invention is that the thickness of the organic polymer is in the range of 100 nanometers to 500 micrometers.

[0010] Another object of the present invention is 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.

[0011] Another object of the present invention is to provide a film, characterized in that the film contains the aforementioned light-converting powder with a protective structure inside.

[0012] Another object of the present invention is to provide a method for preparing a light-converting powder protective structure, the steps of which include:

[0013] Preparing an organic light-converting powder formed from a benzotriazole derivative;

[0014] Selecting a suitable organic polymer;

[0015] Dissolving the organic light conversion powder and the organic polymer to obtain a first solvent;

[0016] Add dispersant to water to obtain the second solution

[0017] The first solution is dispersed in the second solution to obtain an emulsion; and

[0018] The emulsion is heated to evaporate the solvent to obtain a layer of organic polymer on the outside of the organic light-converting powder.

[0019] Another object of the present invention is that the solvent of the first solution includes dichloromethane.

[0020] Another object of the present invention is that the dispersant of the second solution includes polyvinyl alcohol. DETAILED DESCRIPTION

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] Embodiment:

[0026] When implementing the present invention, a certain amount of organic light-converting powder formed by benzotriazole derivatives, for example, 0.05 g, can be first taken, and then a certain amount of polymethyl methacrylate (PMMA), for example, 1 g, can be taken. After the two are mixed, a solvent, for example, 40 g of dichloromethane, is added until they are completely dissolved to obtain a first solution.

[0027] Afterwards, a certain amount of dispersant, such as sodium dodecyl sulfate (SDS), for example 0.2 g, is taken and added to another dispersant, such as 60 g of 2 wt % aqueous solution of polyvinyl alcohol (PVA), to completely dissolve the polyvinyl alcohol (PVA) to obtain a second solution.

[0028] 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 20 minutes, and then 40 g of 2 wt% polyvinyl alcohol (PVA) aqueous solution is added, the rotation speed is adjusted to 300 rpm, the temperature is raised to 35°C, and stirred in an open environment for 10 hours until the dichloromethane solvent is completely evaporated.

[0029] Then, the mixture was 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 wrapped with an organic polymer. With the above-mentioned manufacturing method, a protective layer of an organic polymer can be formed on the outside of an organic light-converting powder formed by a benzotriazole derivative, for example; and of course, after having one layer, two or more layers can be formed on the outside of the light-converting powder. However, the subject matter of this application is structural description and protection, so other details of the manufacturing method will not be described in detail in this application.

[0030] The above-mentioned embodiments can be simplified by the following steps:

[0031] Preparing an organic light-converting powder formed from a benzotriazole derivative;

[0032] Selecting a suitable organic polymer;

[0033] Dissolving the organic light conversion powder and the organic polymer to obtain a first solution;

[0034] Add dispersant to water to obtain the second solution

[0035] The first solution is dispersed in the second solution to obtain an emulsion; and

[0036] The emulsion is heated to evaporate the solvent to obtain a layer of organic polymer on the outside of the organic light-converting powder. The organic polymer can be one layer, two layers or more layers.

[0037] 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 coating protective layer 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 organic light-converting powders that are compatible with benzotriazole derivatives with a refractive index of 1.5 to 1.6, thereby forming an organic protective layer that effectively protects the light-converting powder. 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 protective structure of a light-converting powder, wherein the light-converting powder is an organic light-converting powder formed by a benzotriazole derivative, characterized in that: The protective structure is formed outside the light-converting powder and can form at least one layer of organic polymer covering the light-converting powder.

2. The protective structure of the light conversion powder according to claim 1 is characterized in that: The organic polymer 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 protective structure of the light conversion powder according to claim 1 is characterized in that: The organic polymer is two layers.

4. The protective structure of the light conversion powder according to claim 1 is characterized in that: The thickness of the organic polymer ranges from 100 nanometers to 500 micrometers.

5. The protective structure of the light conversion powder according to claim 1 is characterized in that: The difference between the refractive index of the organic polymer and the refractive index of the light conversion powder is between 0 and 0.

2.

6. A film, characterized in that , the adhesive film contains the protective structure of the light conversion powder in any one of claims 1-4.

7. A method for preparing a light-converting powder protective structure, characterized in that , the preparation method comprises: Preparing an organic light-converting powder formed from a benzotriazole derivative; Selecting a suitable organic polymer; Dissolving the organic light conversion powder and the organic polymer to obtain a first solution; Adding a dispersant to water to obtain a second solution; The first solution is dispersed in the second solution to obtain an emulsion; as well as The emulsion is heated to evaporate the solvent to obtain a layer of organic polymer on the outside of the organic light-converting powder.

8. The method for preparing the light conversion powder protection structure according to claim 7, characterized in that: The organic polymer 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.

9. The method for preparing the light conversion powder protection structure according to claim 8, characterized in that: The solvent of the first solution includes dichloromethane.

10. The method for preparing the light conversion powder protection structure according to claim 9, characterized in that: The dispersant of the second solution includes polyvinyl alcohol.