Friction-resistant light diffusion film and method for manufacturing the same

Abstract

The present invention discloses a friction-resistant light diffusion film, comprising a PET substrate layer, a light diffusion layer is provided on the upper surface of the PET substrate layer, an isolation layer is provided on the lower surface of the PET substrate layer, the isolation layer comprises a first resin coating and a plurality of soft particles, the first resin coating is fixed on the lower surface of the PET substrate layer by coating, the soft particles are embedded in the surface of the first resin coating, the soft particles form an uneven plane on the surface of the isolation layer, an anti-friction layer is provided on the side of the isolation layer away from the PET substrate layer, the anti-friction layer covers the first resin coating and the surface of the soft particles of the isolation layer. The present invention provides a friction-resistant light diffusion film, which can better protect the particles on the surface of the isolation layer of the light diffusion film, reduce the friction coefficient of the light diffusion film, and improve the friction resistance of the light diffusion film. The present invention also provides a method for preparing a friction-resistant light diffusion film.

Description

Technical Field

[0001] The present invention relates to the technical field of light diffusion films, and in particular to a friction-resistant light diffusion film and a manufacturing method thereof. Background Art

[0002] Diffusion film mainly refers to the backlight source part used in LCD modules. In the backlight structure, it mainly plays the role of correcting the diffusion angle, which will increase the light radiation area, but reduce the light intensity per unit area, that is, reduce the brightness. After the light source is diffused by the diffusion material, it can become a secondary light source with a larger area, better uniformity and stable color. It has the function of diffusing light, that is, the light will scatter on its surface, and the light will be spread softly and evenly; the basic structure of most diffusion films is on a transparent substrate, such as PET, with optical light-scattering particles coated on both sides.

[0003] Diffusion film is mainly used in the backlight of mobile phones. The scattering effect of the diffusion film can achieve uniform backlight brightness. It is divided into three layers through optical diffusion. The first layer is the light diffusion layer, the second layer is the PET substrate layer, and the third layer is the isolation layer. In order to improve the scratch resistance of the isolation layer particles, PA with a low friction coefficient, that is, nylon particles, or even Teflon particles, will be selected. Due to the low friction coefficient of the particle surface, the bonding strength is relatively poor when the glue is cured, and it is easy for particles to fall off and break during use, resulting in the light diffusion film not having good friction resistance. Summary of the invention

[0004] The object of the present invention is to provide a friction-resistant light diffusion film and a method for manufacturing the same, so that particles on the surface of the light diffusion film isolation layer can be better protected, and the friction coefficient of the light diffusion film can be reduced to improve the friction resistance of the light diffusion film.

[0005] The technical solution adopted by a friction-resistant light diffusion film and a preparation method thereof disclosed in the present invention is:

[0006] A friction-resistant light diffusion film comprises a PET substrate layer, a light diffusion layer is provided on the upper surface of the PET substrate layer, an isolation layer is provided on the lower surface of the PET substrate layer, the isolation layer comprises a first resin coating and a plurality of micro-soft particles, the first resin coating is fixed on the lower surface of the PET substrate layer by coating, the micro-soft particles are embedded in the surface of the first resin coating, the micro-soft particles form an uneven plane on the surface of the isolation layer, an anti-friction layer is provided on the side of the isolation layer away from the PET substrate layer, and the anti-friction layer covers the first resin coating and the surface of the micro-soft particles of the isolation layer.

[0007] As a preferred solution, the light diffusion layer includes a second resin coating and a plurality of diffusion particles, the second resin coating is fixed on the upper surface of the PET substrate by coating, and the diffusion particles are embedded in the surface of the second resin coating.

[0008] As a preferred solution, the thickness of the PET substrate layer is 38-100 μm, the thickness of the light diffusion layer is 9-11 μm, the thickness of the isolation layer is 8-10 μm, and the thickness of the anti-friction layer is 1-2 μm.

[0009] As a preferred embodiment, the microgranules are PBMA microspheres.

[0010] A method for preparing a friction-resistant light diffusion film comprises the following steps:

[0011] S1, coating configuration, pre-configuring the light diffusion layer coating, isolation layer coating and anti-friction layer coating;

[0012] S2, performing a coating process of the light diffusion layer, coating the light diffusion layer coating prepared in S1 on the upper surface of the PET substrate layer;

[0013] S3, drying the light diffusion layer, drying the upper surface of the PET substrate layer coated in S2 to solidify the light diffusion layer coating on the upper surface of the PET substrate layer;

[0014] S4, performing a coating process of the isolation layer, coating the isolation layer coating prepared in S1 on the lower surface of the PET substrate layer;

[0015] S5, drying the isolation layer, drying the lower surface of the PET substrate layer coated in S4 to solidify the isolation layer coating on the lower surface of the PET substrate layer;

[0016] S6, performing a coating process of the anti-friction layer, coating the anti-friction layer coating prepared in S1 on the surface of the isolation layer formed by curing in S5;

[0017] S7, drying the anti-friction layer, drying the anti-friction layer coating applied in S6 to form an anti-friction layer on the surface of the isolation layer;

[0018] S8, testing the finished product after drying in S7, and the finished product that meets the testing requirements forms the above-mentioned friction-resistant light diffusion film.

[0019] As a preferred solution, the weight percentage ratio of each raw material of the light diffusion layer coating is 100 hydroxy acrylic resin: 20-25 ethyl acetate: 10-20 butyl acetate: 5-10 PMMA: 1-3 curing agents. The PMMA particles are mixed with the diluent and dispersed using a high-speed disperser, and then the hydroxy acrylic resin is added and dispersed using a high-speed dispersant, and finally the curing agent is added and dispersed using a high-speed dispersant to complete the coating preparation process for the diffusion layer.

[0020] As a preferred solution, the weight percentage ratio of each raw material of the isolation layer coating is 100 acrylic resin: 40-50 ethyl acetate: 25-35 PBMA particle resin: 1-3 curing agent. The PBMA particles and the diluent are dispersed using a high-speed disperser, and then the acrylic resin is added to continue dispersing, and finally the curing agent is added to continue dispersing for 10 minutes to complete the coating preparation process of the isolation layer.

[0021] As a preferred embodiment, the anti-friction layer coating includes a main agent and a curing agent, and the mass percentage ratio of the main agent to the curing agent is 8 to 10:1; the main agent contains the following components and contents: 55% to 60% tetrafluoro resin, 1% to 3% film-forming aid, 25% to 32% filler, and 5% to 19% solvent; the curing agent contains: polyisocyanate, first add tetrafluoro resin, film-forming aid, filler and solvent to a high-speed disperser for dispersion, and then add the curing agent to the high-speed disperser and continue to disperse for 10 minutes to complete the coating preparation process for coating the anti-friction layer.

[0022] As a preferred embodiment, the tetrafluoro resin is vinyl tetrafluoro resin.

[0023] As a preferred solution, the drying process adopts a multi-gradient drying process, including 6 drying boxes, which use different temperatures for multi-gradient drying process.

[0024] The beneficial effects of a friction-resistant light diffusion film disclosed in the present invention are as follows: a light diffusion layer is provided on the upper surface of a PET substrate layer, and the light diffusion layer plays a role of light diffusion; an isolation layer is provided below the PET substrate layer, and the isolation layer mainly plays a role of spacing to prevent the friction-resistant light diffusion film from forming a covering interference with PC; and an anti-friction layer is also provided on the surface of the isolation layer, and the anti-friction layer covers the first resin coating and the surface of the micro particles of the isolation layer. The anti-friction layer mainly reduces the surface friction coefficient of the light diffusion film, making the surface of the light diffusion film smoother and not easy to scratch the light guide plate, and can also protect the micro particles on the isolation layer to prevent the micro particles from falling off from the first resin coating, thereby better protecting the micro particles on the surface of the isolation layer of the friction-resistant light diffusion film. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a friction-resistant light diffusion film of the present invention. DETAILED DESCRIPTION

[0026] The present invention will be further described and illustrated below in conjunction with specific embodiments and accompanying drawings:

[0027] Please refer to Figure 1A friction-resistant light diffusion film includes a PET substrate layer 10, a light diffusion layer 20 is provided on the upper surface of the PET substrate layer 10, and an isolation layer 30 is provided on the lower surface of the PET substrate layer 10.

[0028] The isolation layer 30 includes a first resin coating 31 and a plurality of soft particles 32. The first resin coating 31 is fixed on the lower surface of the PET substrate layer 10 by coating, and the soft particles 32 are embedded in the surface of the first resin coating 31. The soft particles 32 make the surface of the isolation layer 30 form an uneven plane.

[0029] An anti-friction layer 40 is disposed on the side of the isolation layer 30 away from the PET substrate layer 10 . The anti-friction layer 40 covers the first resin coating 31 and the surface of the micro particles 32 of the isolation layer 30 .

[0030] A light diffusion layer 20 is provided on the upper surface of the PET substrate layer 10, which plays a role of light diffusion; an isolation layer 30 is provided below the PET substrate layer 10, which mainly plays a role of spacing to prevent the friction-resistant light diffusion film from forming covering interference with the PC.

[0031] In addition, an anti-friction layer 40 is provided on the surface of the isolation layer 30. The anti-friction layer 40 covers the first resin coating 31 and the surface of the soft particles 32 of the isolation layer 30. The anti-friction layer 40 mainly reduces the friction coefficient of the light diffusion film surface, making the light diffusion film surface smoother and not easy to scratch the light guide plate. The soft particles 32 on the isolation layer 30 can also be protected to prevent the soft particles 32 from falling off from the first resin coating 31, so that the soft particles 32 on the surface of the friction-resistant light diffusion film isolation layer 30 are better protected.

[0032] The light diffusion layer 20 includes a second resin coating 21 and a plurality of diffusion particles 22. The second resin coating 21 is fixed on the upper surface of the PET substrate by coating, and the diffusion particles 22 are embedded in the surface of the second resin coating 21. The diffusion particles 22 are fixed by the second resin coating 21 to prevent the diffusion particles 22 from loosening, and the second resin coating 21 can protect the upper surface of the PET substrate layer 10.

[0033] In the above scheme, the thickness of the PET substrate layer 10 is 38-100 μm, the thickness of the light diffusion layer 20 is 9-11 μm, the thickness of the isolation layer 30 is 8-10 μm, and the thickness of the anti-friction layer 40 is 1-2 μm. People can select PET substrate layers 10 of different thicknesses for coating according to different backlight sources, thereby forming optical diffusion films of different thicknesses, which are applied to different backlight sources, and by controlling the thickness of the light diffusion layer 20, the isolation layer 30 and the anti-friction layer 40, the thickness of the friction-resistant light diffusion film can be avoided to be too large, which affects the use.

[0034] Furthermore, the above-mentioned soft particles 32 are made of PBMA microspheres, which have good elasticity and thus have a compression resistance effect.

[0035] A method for preparing a friction-resistant light diffusion film comprises the following steps:

[0036] The first step is coating configuration, which is to pre-configure the light diffusion layer coating, the isolation layer coating and the anti-friction layer coating; thereby facilitating subsequent multiple different coating processes on the PET substrate layer.

[0037] The second step is to carry out coating treatment of the light diffusion layer, and to coat the light diffusion layer coating prepared in the first step on the upper surface of the PET substrate layer.

[0038] The third step is drying the light diffusion layer, drying the upper surface of the PET substrate layer coated in the second step to solidify the light diffusion layer coating on the upper surface of the PET substrate layer, thereby forming a light diffusion layer on the upper surface of the PET substrate layer.

[0039] The fourth step is to carry out coating treatment of the isolation layer, and to coat the isolation layer coating prepared in the first step on the lower surface of the PET substrate layer.

[0040] The fifth step is to dry the isolation layer. The lower surface of the PET substrate layer coated in the fourth step is dried to solidify the isolation layer coating on the lower surface of the PET substrate layer.

[0041] The sixth step is to carry out coating treatment of the anti-friction layer, coating the anti-friction layer coating prepared in the first step on the surface of the isolation layer formed by curing in the fifth step.

[0042] In the seventh step, the anti-friction layer coating applied in the sixth step is dried to form an anti-friction layer on the surface of the isolation layer, and the isolation layer is protected by the anti-friction layer.

[0043] In the eighth step, the finished product after drying in the seventh step is tested, and the finished product that meets the test requirements is the above-mentioned friction-resistant light diffusion film.

[0044] In the actual production and processing process, the coating sequence of the upper surface and the lower surface of the PET substrate layer does not affect the final coating effect, and the coating sequence can be adjusted according to the actual production requirements.

[0045] And in the whole coating process, automated coating equipment can be used for coating processing, thereby improving coating efficiency, reducing labor and improving product quality.

[0046] The weight percentage ratio of each raw material of the light diffusion layer coating is 100 hydroxy acrylic resin: 20-25 ethyl acetate: 10-20 butyl acetate: 5-10 PMMA: 1-3 curing agents. The PMMA particles are mixed with the diluent and dispersed using a high-speed disperser, and then the hydroxy acrylic resin is added and dispersed using a high-speed dispersant, and finally the curing agent is added and dispersed using a high-speed dispersant to complete the coating preparation process for the diffusion layer.

[0047] The light diffusion layer coating components are selected and the proportion is controlled to obtain a light diffusion film with excellent light diffusion function, high optical brightness, good haze and light transmittance, high aging resistance and stable quality. PMMA particles are mainly used for light diffusion, acrylic resin is used to fix PMMA particles, and the diluent is mainly used to control viscosity and solid content.

[0048] The weight percentage of each raw material of the isolation layer coating is acrylic resin 100: ethyl acetate 40-50: PBMA particle resin 25-35: curing agent 1-3. The PBMA particles and diluent are dispersed using a high-speed disperser, and then the acrylic resin is added to continue to disperse, and finally the curing agent is added to continue to disperse for 10 minutes to complete the coating preparation process of the isolation layer. The particles required for the isolation layer have a certain elasticity. The particle material is selected as soft particle PBMA microspheres, which can better deform elastically to prevent the light guide plate from being crushed.

[0049] The anti-friction layer coating includes a main agent and a curing agent, the mass percentage of the main agent and the curing agent is 8-10:1; the main agent contains the following components and contents: tetrafluoro resin 55%-60%, film-forming aid 1%-3%, filler 25%-32%, solvent 5%-19%; the curing agent contains: polyisocyanate, first add tetrafluoro resin, film-forming aid, filler and solvent into a high-speed disperser for dispersion, then add the curing agent into the high-speed disperser and continue to disperse for 10 minutes to complete the coating preparation process for coating the anti-friction layer.

[0050] And tetrafluororesin is vinyl tetrafluororesin, fluororesin is a kind of thermoplastic resin containing fluorine atoms in its molecular structure. It has excellent high and low temperature resistance, dielectric properties, chemical stability, weather resistance, non-flammability, non-stickiness and low friction coefficient. Taking advantage of the non-stickiness and low friction coefficient of fluororesin, the lower the friction coefficient, the smoother the product is and it is not easy to scratch the PC board.

[0051] The above drying process adopts multi-gradient drying process, including 6 drying ovens, and adopts different temperatures for multi-gradient drying process. The temperature range of the drying oven is 40℃-60℃ for the first oven, 60℃-90℃ for the second oven, 70℃-90℃ for the third oven, 90℃-110℃ for the fourth oven, 70℃-90℃ for the fifth oven, and 30℃-50℃ for the sixth oven. So that different coatings can be cured better.

[0052] The finished products after coating are subjected to haze and transmittance tests, cross-grid adhesion tests, friction resistance tests, compression tests, pencil hardness tests, aging resistance tests, environmental RA tests, yellowing resistance tests, etc., before the finished products with good quality can be used or sold.

[0053] The following table shows the comparison of friction coefficients after the anti-friction layer is used in this solution:

[0054]

[0055] Thereby, the friction coefficient of the light diffusion film can be reduced to a limited extent, and the friction resistance of the light diffusion film can be improved.

[0056] The present invention provides a friction-resistant light diffusion film. A light diffusion layer is arranged on the upper surface of a PET substrate layer. The light diffusion layer plays a role of light diffusion. An isolation layer is arranged below the PET substrate layer. The isolation layer mainly plays a role of spacing to prevent the friction-resistant light diffusion film from forming a covering interference with PC. An anti-friction layer is also arranged on the surface of the isolation layer. The anti-friction layer covers the first resin coating and the surface of the micro particles of the isolation layer. The anti-friction layer mainly reduces the friction coefficient of the surface of the light diffusion film, making the surface of the light diffusion film smoother and not easy to scratch the light guide plate. The anti-friction layer can also protect the micro particles on the isolation layer to prevent the micro particles from falling off from the first resin coating, so that the micro particles on the surface of the isolation layer of the friction-resistant light diffusion film are better protected.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for preparing a friction-resistant light diffusion film, characterized in that: The following steps are involved: S1, coating configuration, pre-configuring the light diffusion layer coating, isolation layer coating and anti-friction layer coating; S2, performing a coating process of the light diffusion layer, coating the light diffusion layer coating prepared in S1 on the upper surface of the PET substrate layer; S3, drying the light diffusion layer, drying the upper surface of the PET substrate layer coated in S2 to solidify the light diffusion layer coating on the upper surface of the PET substrate layer; S4, performing a coating process of the isolation layer, coating the isolation layer coating prepared in S1 on the lower surface of the PET substrate layer; S5, drying the isolation layer, drying the lower surface of the PET substrate layer coated in S4 to solidify the isolation layer coating on the lower surface of the PET substrate layer; S6, performing a coating process of the anti-friction layer, coating the anti-friction layer coating prepared in S1 on the surface of the isolation layer formed by curing in S5; S7, drying the anti-friction layer, drying the anti-friction layer coating applied in S6 to form an anti-friction layer on the surface of the isolation layer; S8, testing the finished product after drying in S7, and forming a friction-resistant light diffusion film for the finished product that meets the testing requirements; The weight percentage ratio of each raw material of the isolation layer coating is 100 acrylic resin: 40-50 ethyl acetate: 25-35 PBMA particle resin: 1-3 curing agent. The PBMA particles and the diluent are dispersed using a high-speed disperser, and then the acrylic resin is added to continue dispersing, and finally the curing agent is added to continue dispersing for 10 minutes to complete the coating preparation process of the isolation layer. The anti-friction layer coating comprises a main agent and a curing agent, wherein the mass percentage of the main agent and the curing agent is 8 to 10:1; the main agent comprises the following components and contents: 55% to 60% tetrafluoro resin, 1% to 3% film-forming aid, 25% to 32% filler, and 5% to 19% solvent; the curing agent comprises: polyisocyanate, and the tetrafluoro resin, film-forming aid, filler and solvent are first added to a high-speed disperser for dispersion, and then the curing agent is added to the high-speed disperser for continued dispersion for 10 minutes to complete the coating preparation process for coating the anti-friction layer.

2. The method for preparing a friction-resistant light diffusion film according to claim 1, characterized in that: The weight percentage ratio of each raw material of the light diffusion layer coating is 100 hydroxy acrylic resin: 20-25 ethyl acetate: 10-20 butyl acetate: 5-10 PMMA: 1-3 curing agents. PMMA particles are mixed with a diluent and dispersed using a high-speed disperser. Then, hydroxy acrylic resin is added and dispersed using a high-speed dispersant. Finally, a curing agent is added and dispersed using a high-speed dispersant to complete the coating preparation process for the diffusion layer. 3 . The method for preparing a friction-resistant light diffusion film according to claim 1 , wherein the tetrafluoro resin is a vinyl tetrafluoro resin.

4. A method for preparing a friction-resistant light diffusion film as described in claim 1, wherein the drying process adopts a multi-gradient drying process, including 6 drying ovens, and uses different temperatures for multi-gradient drying process.

5. A friction-resistant light diffusion film, characterized in that: The friction-resistant light diffusion film prepared by the method described in any one of claims 1 to 4 comprises a PET substrate layer, a light diffusion layer is provided on the upper surface of the PET substrate layer, an isolation layer is provided on the lower surface of the PET substrate layer, the isolation layer comprises a first resin coating and a plurality of micro-soft particles, the first resin coating is fixed on the lower surface of the PET substrate layer by coating, the micro-soft particles are embedded in the surface of the first resin coating, the micro-soft particles form an uneven plane on the surface of the isolation layer, an anti-friction layer is provided on the side of the isolation layer away from the PET substrate layer, and the anti-friction layer covers the first resin coating and the surface of the micro-soft particles of the isolation layer.

6. The friction-resistant light diffusion film according to claim 5, characterized in that: The light diffusion layer includes a second resin coating and a plurality of diffusion particles. The second resin coating is fixed on the upper surface of the PET substrate by coating, and the diffusion particles are embedded in the surface of the second resin coating.

7. The friction-resistant light diffusion film according to claim 6, characterized in that: The thickness of the PET substrate layer is 38-100 μm, the thickness of the light diffusion layer is 9-11 μm, the thickness of the isolation layer is 8-10 μm, and the thickness of the anti-friction layer is 1-2 μm.

8. The friction-resistant light diffusion film according to claim 5, characterized in that: The micro particles are PBMA microspheres.

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