A highly weather-resistant reflective film

Abstract

The utility model relates to a highly weather-resistant reflective film, which belongs to the technical field of reflective materials. In order to solve the problem of poor weather resistance in the prior art, a highly weather-resistant reflective film is provided, the reflective film comprising a substrate layer, a reflective layer and a PMMA surface layer, the reflective layer is located between the PMMA surface layer and the substrate layer, the surface of the PMMA surface layer is also coated with a transparent high-refractive-index resin coating, and the refractive index of the high-refractive-index resin layer is higher than the refractive index of the PMMA surface layer. The reflective film can effectively reflect more short-wavelength ultraviolet light to the outside world, improve the overall aging resistance of the reflective film, and increase the service life.

Description

Technical Field

[0001] The utility model relates to a highly weather-resistant reflective film, belonging to the technical field of reflective materials. Background Art

[0002] As an important traffic safety material, reflective film is widely used in road signs, vehicle identification, clothing identification and other fields to achieve functions such as indicators and warnings. The performance of reflective film directly affects traffic safety and visual effects. However, traditional reflective film often degrades in performance during use due to insufficient weather resistance or aging resistance, affecting the reflective effect and service life. This is mainly because the main materials of current reflective films are generally PET, PVC, PC and other materials. After use, their durability will decrease over time, and the product will age. Usually, yellowing, powdering, fading and cracking will occur, which will reduce the performance of the reflective film and even cause it to fail. The materials between the layers of the current reflective film usually use PMMA material for the surface layer and PC material for the reflective layer. Although the weather resistance of PMMA on the surface layer is better than that of PC, which improves the overall weather resistance of the reflective film to a certain extent, another reason for the aging phenomenon is that a large amount of short-wave ultraviolet rays in the light irradiate the main materials in the reflective layer, such as PC, etc., causing aging and other phenomena. The current reflective film has a poor reflection effect on short-wavelength ultraviolet rays. Ultraviolet rays irradiate into the reflective layer for a long time, causing the PC, PVC, and PET materials therein to age and turn yellow due to the irradiation of ultraviolet rays, which reduces the overall service life of the reflective film and is not conducive to adapting to the environment of long-term application. Summary of the invention

[0003] The purpose of the utility model is to provide a highly durable reflective film in view of the above problems existing in the prior art, in order to solve the problem of poor weather resistance of the prior art.

[0004] The purpose of the utility model is achieved through the following technical solutions: a highly weather-resistant reflective film, the reflective film comprising a substrate layer, a reflective layer and a PMMA surface layer, the reflective layer is located between the PMMA surface layer and the substrate layer, the surface of the PMMA surface layer is also coated with a transparent high-refractive index resin coating, and the refractive index of the high-refractive index resin coating is higher than the refractive index of the PMMA surface layer.

[0005] By adding a high-refractive-index resin coating on the upper surface of the PMMA surface layer of the reflective film, and making the refractive index of the high-refractive-index resin coating higher than that of the PMMA surface layer as a whole, a certain refractive-index difference is formed between the two layers, which is equivalent to increasing the interlayer interface reflection and refraction, and can reflect more short-wavelength ultraviolet rays to the outside world, avoiding the problem of excessive aging of the reflective layer materials such as PC due to the large amount of ultraviolet rays entering, thereby improving the overall aging resistance of the reflective film and achieving a longer service life of the reflective film. Specifically, by adopting a high-refractive-index resin coating, the refraction and reflection characteristics of the reflective film to light are optimized, and the reflection efficiency of the reflective film is enhanced. This is equivalent to adding a layer of high-refractive-index coating on the surface. When light irradiates the surface of the reflective film, a part of the ultraviolet light is reflected, and when the light enters the high-refractive coating, a part of the light is reflected to the outside world. The other part of the light can be refracted after passing through the high-refractive resin coating and enter the PMMA surface layer and the reflective layer on the surface of the reflective layer. In this way, after the light irradiates the reflective layer, more short-wave ultraviolet light can be reflected into the external environment, effectively avoiding excessive ultraviolet rays from entering the materials in the reflective layer and / or the materials in the substrate, such as PC, etc., causing aging defects too quickly, improving the aging resistance of the reflective film, effectively avoiding the yellowing phenomenon of the materials in the reflective layer, and effectively ensuring the reflective quality.

[0006] In the above-mentioned high weather-resistant reflective film, the refractive index of the PMMA surface layer is 1.45-1.48, and the refractive index of the high-refractive-index resin coating is 1.60-1.70. By utilizing the interfacial refractive index difference formed between the above-mentioned high-refractive-index resin coating and the PMMA surface layer, the irradiated light can be better partially reflected at the interface, especially the ultraviolet light can be reflected at the interface, and then the incident direction of the light is changed by utilizing the characteristics of the high refractive index after passing through the interface, so that after the light passes through the PMMA surface layer and the reflective layer, it is reflected and refracted so that more short-wave ultraviolet light is reflected to the outside world, and the amount of ultraviolet light entering the reflective layer is more effectively reduced, thereby reducing the influence of ultraviolet light in the light on the material in the reflective layer, reducing the deterioration and aging phenomenon such as yellowing of the material caused by excessive ultraviolet irradiation, and effectively ensuring the overall performance of the reflective film and ensuring a better service life.

[0007] In the above-mentioned high weather-resistant reflective film, the thickness of the high refractive index resin coating is a thiol-modified epoxy resin layer, so that the coating can maintain the characteristics of high refractive index as a whole and have excellent light transmittance, so as to ensure that the reflective film as a whole has high reflectivity and high brightness effects.

[0008] In the above-mentioned high weather-resistant reflective film, the thickness of the high refractive index resin coating is 5μm to 15μm; the thickness of the PMMA surface layer is 70μm to 85μm. The thinner coating thickness of the added coating can effectively make the interlayer interface with the PMMA surface layer have the characteristics of high and low refractive index difference, and can also keep the overall high brightness characteristics.

[0009] In the above-mentioned highly weather-resistant reflective film, the substrate layer includes a PC layer and a pressure-sensitive adhesive layer, and the PC layer is located between the reflective layer and the pressure-sensitive adhesive layer.

[0010] In the above-mentioned high weather-resistant reflective film, the reflective layer adopts a micro-prism structure film layer. The reflective layer adopting the micro-prism structure makes the whole have a high reflectivity effect, which can better achieve the advantage of high brightness.

[0011] In the above-mentioned highly weather-resistant reflective film, as another embodiment, the reflective layer adopts a glass microbead structure film layer.

[0012] In the above-mentioned high weather-resistant reflective film, the surface of the pressure-sensitive adhesive layer is covered with a release paper layer, and the surface adhesion of the pressure-sensitive adhesive layer can be ensured by the provision of the release paper.

[0013] Compared with the existing technology, this highly weather-resistant reflective film has the following advantages:

[0014] 1. By adding a high-refractive-index resin coating on the surface layer, a certain refractive-index difference is formed between the layers, which can effectively reflect more short-wavelength ultraviolet light to the outside world, improve the overall aging resistance of the reflective film, and increase its service life.

[0015] 2. The coating layer is a mercaptan-modified epoxy resin layer, which allows the coating to maintain a high refractive index and excellent light transmittance, ensuring that the reflective film has high reflectivity and high brightness. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the cross-sectional structure of the high-durability reflective film.

[0017] In the figure, 1, substrate layer; 11, PC layer; 12, pressure-sensitive adhesive layer; 2, reflective layer; 3, PMMA surface layer; 4, high refractive index resin coating; 5, release paper layer. DETAILED DESCRIPTION

[0018] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0019] Example 1

[0020] Combination Figure 1As shown, the high weather-resistant reflective film comprises a substrate layer 1, a reflective layer 2 and a PMMA surface layer 3, wherein the reflective layer 2 is located between the PMMA surface layer 3 and the substrate layer 1, and more importantly, the surface of the PMMA surface layer 3 is also coated with a transparent high-refractive-index resin coating 4, and the refractive index of the high-refractive-index resin coating 4 is higher than that of the PMMA surface layer 3. By adding a layer of high-refractive-index resin coating 4 on the surface, the inter-layer reflection effect can be better increased, especially the reflection of ultraviolet rays in the light, so that more ultraviolet rays can be reflected into the external environment, and at the same time, by utilizing the refraction effect of the high-refractive-index coating on the incident light, more light can be reflected out of the outside world in the reflective layer 2, and more ultraviolet rays can be reflected into the outside world, thereby effectively reducing the influence of ultraviolet rays in the light on the materials in the reflective layer, reducing the yellowing phenomenon of the materials in the reflective layer, ensuring its reflective performance and quality, and also improving the overall service life of the reflective film. In a further embodiment, it is preferred that the refractive index of the PMMA surface layer 3 is 1.45 to 1.48, and the refractive index of the high-refractive-index resin coating 4 is 1.60 to 1.70.

[0021] In a further embodiment, the high refractive index resin coating 4 is a thiol-modified epoxy resin layer. The thiol-modified epoxy resin layer is a known material thiol-modified epoxy resin. It has a high refractive index and the formed resin layer has good light transmittance. It is best to make the high refractive index resin coating 4 have a thickness of 5 μm to 15 μm; preferably 10 μm, and the thickness of the PMMA surface layer 3 is 70 μm to 85 μm, preferably 80 μm.

[0022] The substrate layer 1 can be made of any material used in common reflective films. For better implementation, it is best to make the substrate layer 1 include a PC layer 11 and a pressure-sensitive adhesive layer 12 , and the PC layer 11 is located between the reflective layer 2 and the pressure-sensitive adhesive layer 12 .

[0023] A micro-prismatic film layer is used for the above-mentioned reflective layer 2. The micro-prismatic film layer itself can be any general one. Further, the micro-prismatic film layer can include a micro-prismatic film layer and a surface layer formed by a PC material, so that the surface layer is located on the side of the PMMA surface layer 3, that is, the surface layer formed by the PC material is between the PMMA surface layer 3 and the micro-prismatic film layer, and an air layer is formed between the micro-prismatic film layer and the PC layer of the substrate layer 1. When the micro-prismatic film layer is used, the thickness of the reflective layer 2 is controlled to be 300μm to 350μm.

[0024] As another embodiment, the above-mentioned reflective layer 2 can also be a glass micro-bead structure film layer. The glass micro-bead structure film layer itself is also a common reflective layer 2 with a glass micro-bead layer. The effect of high reflectivity can also be achieved. When the micro-prism structure film layer is used, the thickness of the reflective layer 2 is controlled to be 250μm to 280μm.

[0025] A layer of release paper layer 5 may be further adhered to the surface of the pressure-sensitive adhesive layer 12 to protect the surface viscosity of the pressure-sensitive adhesive layer 12 and prevent it from being contaminated and affecting its surface quality.

[0026] Example 2

[0027] In order to better illustrate the performance of the high weather-resistant reflective film, the structural characteristics of the specific high weather-resistant reflective film are used for illustration below.

[0028] The high weather-resistant reflective film comprises a substrate layer 1, a reflective layer 2 and a PMMA surface layer 3, wherein the reflective layer 2 is located between the PMMA surface layer 3 and the substrate layer 1, and the surface of the PMMA surface layer 3 is also coated with a transparent high-refractive-index resin coating 4, and the refractive index of the high-refractive-index resin coating 4 is higher than the refractive index of the PMMA surface layer 3. The high-refractive-index resin coating 4 is a thiol-modified epoxy resin layer, the refractive index of which is selected to be 1.67, and the thickness is 5 μm to 15 μm. The refractive index of the PMMA surface layer 3 is selected to be 1.48, and the thickness of the PMMA surface layer 3 is controlled to be 70 μm to 85 μm, preferably 80 μm.

[0029] The above-mentioned reflective layer 2 adopts a micro-prismatic film layer. It can be a reflective layer of a general micro-prismatic film layer, or the micro-prismatic film layer here can adopt a surface layer formed by a micro-prismatic film layer and a PC material, so that the surface layer is located on the side of the PMMA surface layer 3, that is, the surface layer formed by the PC material is between the PMMA and the micro-prismatic film layer, and an air layer is formed between the micro-prismatic film layer and the PC layer of the substrate layer 1. The thickness of the reflective layer 2 is controlled at 300μm.

[0030] Meanwhile, the substrate layer 1 includes a PC layer 11 and a pressure-sensitive adhesive layer 12 , and the PC layer 11 is located between the reflective layer 2 and the pressure-sensitive adhesive layer 12 .

[0031] The aging resistance of the reflective film in this embodiment was tested. The reflective film sample was placed in an accelerated aging box (temperature: 38°C, humidity: 65%, 880W / cm 2 ) Accelerated aging time can reach at least 3500h.

[0032] For comparison, a reflective film without adding the high refractive index resin coating layer 4 (thiol-modified epoxy resin layer) on the surface of the PMMA surface layer 2 was prepared for comparison.

[0033] The results show that, compared with the reflective film without the high refractive index resin coating 4 on the surface (placed in an accelerated aging box (temperature 38°C, humidity: 65%, 880W / Cm 2) The accelerated aging time can only reach about 2500h). This shows that the reflective film product has better performance in aging resistance after the high refractive index resin coating 4 is coated on the surface.

[0034] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0035] Although the terms such as substrate 1, PC layer 11, pressure-sensitive adhesive layer 12, reflective layer 2, PMMA surface layer 3, high refractive index resin coating 4, release paper layer 5 are frequently used in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the utility model; interpreting them as any additional restrictions is contrary to the spirit of the utility model.

Claims

1. A highly weather-resistant reflective film, comprising a substrate layer (1), a reflective layer (2) and a PMMA surface layer (3), wherein the reflective layer (2) is located between the PMMA surface layer (3) and the substrate layer (1), characterized in that: The surface of the PMMA surface layer (3) is also coated with a transparent high-refractive-index resin coating (4), and the refractive index of the high-refractive-index resin coating (4) is higher than the refractive index of the PMMA surface layer (3).

2. The highly weather-resistant reflective film according to claim 1, characterized in that: The refractive index of the PMMA surface layer (3) is 1.45 to 1.48, and the refractive index of the high-refractive-index resin coating (4) is 1.60 to 1.

70.

3. The highly weather-resistant reflective film according to claim 1, characterized in that: The high refractive index resin coating (4) is a thiol-modified epoxy resin layer.

4. The highly weather-resistant reflective film according to claim 1, 2 or 3, characterized in that: The thickness of the high refractive index resin coating (4) is 5 μm to 15 μm; the thickness of the PMMA surface layer (3) is 70 μm to 85 μm.

5. The highly weather-resistant reflective film according to claim 1, 2 or 3, characterized in that: The substrate layer (1) comprises a PC layer (11) and a pressure-sensitive adhesive layer (12), and the PC layer (11) is located between the reflective layer (2) and the pressure-sensitive adhesive layer (12).

6. The highly weather-resistant reflective film according to claim 1, 2 or 3, characterized in that: The reflective layer (2) is a micro-prismatic structure film layer.

7. The highly weather-resistant reflective film according to claim 1, 2 or 3, characterized in that: The reflective layer (2) is a glass microbead structure film layer.

8. The highly weather-resistant reflective film according to claim 5, characterized in that: The outer surface of the pressure-sensitive adhesive layer (12) is adhered with a release paper layer (5).

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