Protective film for paint surface of metal piece

Abstract

The utility model discloses a protective film for a paint surface of a metal piece, which comprises a base material layer provided with a first surface and a second surface which are opposite to each other along the thickness of the film; the repair coating is arranged on the first surface; the bonding layer is arranged on the second surface; the repairing coating comprises an outer repairing layer and an inner repairing layer with the layer thicknesses increasing in sequence, and the hardness of the inner repairing layer is smaller than that of the outer repairing layer. The base material layer comprises a hard base material unit layer and a soft base material unit layer, and the soft base material unit layer is connected with the bonding layer. By adjusting the hardness and the thickness of each layer of the repair coating and combining the arrangement of the hard base material unit layer and the soft base material unit layer, the hardness of the protective film from outside to inside is gradually changed, the problem that the bending resistance and the tensile strength of the protective film are affected due to the fact that the repair coating is too hard is solved, and the phenomenon of delamination is avoided.

Description

Technical Field

[0001] The utility model relates to a protective film for a vehicle, in particular to a metal part paint surface protective film. Background Art

[0002] Paint protection film, also known as "invisible car cover", is a layer of transparent protective film affixed to the surface of the car body. Its main function is to protect the car paint from damage.

[0003] The surface of the current paint protection film is provided with a repair coating, but the hardness of the repair coating is relatively high, which leads to a negative impact on the tensile and bending resistance of the protective film, making it difficult to install and the curved surface is prone to warping.

[0004] Therefore, it is necessary to improve the paint protection film in the prior art. Utility Model Content

[0005] The purpose of the utility model is to overcome the defects existing in the prior art and provide a paint protective film for metal parts. By adjusting the hardness and thickness of each layer of the repair coating and combining the arrangement of a hard substrate unit layer and a soft substrate unit layer, a gradual change in hardness from the outside to the inside of the protective film is obtained, thereby solving the problem of the repair coating being too hard affecting the bending resistance and tensile strength of the protective film and avoiding the occurrence of delamination.

[0006] In order to achieve the above technical effects, the technical solution of the utility model is: a metal paint protection film, comprising:

[0007] A substrate layer having a first surface and a second surface opposite to each other along the film thickness;

[0008] A repair coating is disposed on the first surface;

[0009] an adhesive layer, disposed on the second surface;

[0010] The repair coating comprises an outer repair layer and an inner repair layer with increasing thicknesses in sequence, and the hardness of the inner repair layer is less than the hardness of the outer repair layer;

[0011] The substrate layer includes a hard substrate unit layer and a soft substrate unit layer, and the soft substrate unit layer is connected to the adhesive layer.

[0012] A preferred technical solution is that a hydrophilic layer is provided on the surface of the outer repair layer away from the inner repair layer, or the outer repair layer is a hydrophilic layer.

[0013] A preferred technical solution is that the soft substrate unit layer is a double-layer arrangement, the hard substrate unit layer is sandwiched between the double-layer soft substrate unit layers, the material of the hard substrate unit layer is one or more of PVC, PU and TPU recycled materials, and the material of the soft substrate unit layer is TPU.

[0014] A preferred technical solution is that the soft substrate unit layer and the hard substrate unit layer are connected by a polyurethane hot melt adhesive layer.

[0015] A preferred technical solution is that at least one surface of the hard substrate unit layer is concave-convexly matched with the soft substrate unit layer, or is concave-convexly matched with the polyurethane hot melt adhesive layer.

[0016] A preferred technical solution is that the material of the bonding layer is a high temperature resistant acrylic adhesive.

[0017] A preferred technical solution is that a peeling protective layer is provided on the surface of the repair coating away from the substrate layer, and a PET release film is provided on the surface of the adhesive layer away from the substrate layer.

[0018] A preferred technical solution is that the peeling protection layer includes a PET substrate layer and an elastic buffer layer.

[0019] A preferred technical solution is that one surface of the adhesive layer is connected to the substrate layer, and the other surface is provided with a concave-convex surface, and the concave-convex surface is matched with the PET release film in a concave-convex manner.

[0020] A preferred technical solution is that the repair coating has a thickness of 12 to 18 μm, the substrate layer has a thickness of 100 to 500 μm, and the adhesive layer has a thickness of 20 to 30 μm.

[0021] The advantages and beneficial effects of the utility model are:

[0022] The paint protection film for metal parts has a reasonable structure. By setting an outer repair layer and an inner repair layer, the hardness of the inner repair layer is made smaller than the hardness of the outer repair layer. Combined with the setting of the hard substrate unit layer and the soft substrate unit layer, and adjusting the layer thickness of the outer repair layer and the inner repair layer, the hardness of the protective film is gradually changed from the outside to the inside, thereby solving the problem of the repair coating being too hard affecting the bending resistance and tensile strength of the protective film, and avoiding the occurrence of delamination. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic structural diagram of Embodiment 1 of the metal part paint protection film of the utility model;

[0024] Figure 2 This is a schematic structural diagram of Embodiment 2 of the metal part paint protection film of the utility model;

[0025] Figure 3 It is a structural schematic diagram of Embodiment 3 of the metal part paint protection film of the utility model.

[0026] In the figure: 1. substrate layer; 2. repair coating; 3. adhesive layer; 4. hydrophilic layer; 5. peeling protection layer; 6. PET release film; 10. polyurethane hot melt adhesive layer; 11. soft substrate unit layer; 12. hard substrate unit layer; 21. outer repair layer; 22. inner repair layer; 50. elastic buffer layer; 51. PET substrate layer; 53. release layer. DETAILED DESCRIPTION

[0027] The following is a further description of the specific implementation of the present invention in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0028] The terms “outside”, “inside” and “surface” are based on the normal use state of the paint protective film on metal parts, and are only used to facilitate the description of the present invention and simplify the description, rather than to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0029] The terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention of the utility model, unless otherwise specified, the meaning of "plurality" is two or more.

[0030] like Figures 1 to 3 As shown, the utility model discloses a metal paint protection film, including a substrate layer 1, a repair coating 2 and an adhesive layer 3, the substrate layer 1 has a first surface and a second surface opposite to each other along the film thickness, the repair coating 2 is arranged on the first surface, and the adhesive layer 3 is arranged on the second surface, the repair coating 2 includes an outer repair layer 21 and an inner repair layer 22 with increasing layer thicknesses, and the hardness of the inner repair layer 22 is less than the hardness of the outer repair layer 21; the substrate layer 1 includes a hard substrate unit layer 12 and a soft substrate unit layer 11, and the soft substrate unit layer 11 is connected to the adhesive layer 3.

[0031] The repair coating 2 is usually made by curing a cross-linked resin, and its hardness is closely related to the composition of the raw materials, the functionality of the raw materials, the cross-linking density, the curing conditions, etc.

[0032] By setting up an outer repair layer 21 and an inner repair layer 22 and adjusting the proportion of the cross-linked raw materials in each layer and the curing conditions, two repair layers with different hardnesses are obtained, that is, the hardness of the inner repair layer is less than that of the outer repair layer. Combined with adjusting the thickness of the two layers, the hardness of the repair coating is controlled to change gradually from the outside to the inside, thereby solving the problem of the repair coating being too hard affecting the bending resistance and tensile strength of the protective film, and avoiding the occurrence of delamination.

[0033] The substrate layer formed by combining the hard substrate unit layer 12 and the soft substrate unit layer 11 makes the hardness and softness of the protective film change gradually from the outside to the inside, thereby optimizing the bending resistance and tensile strength of the protective film.

[0034] In some embodiments, the surface of the outer repair layer 21 away from the inner repair layer 22 is provided with a hydrophilic layer 4, and the hydrophilic layer 4 is a coating containing inorganic nanoparticles. Furthermore, the inorganic nanoparticles are silicon dioxide nanoparticles, which have high transparency and therefore do not affect the light transmittance of the protective film; they have good chemical stability and weather resistance and are not easily affected by environmental factors such as humidity and temperature changes, thereby improving the durability of the protective film. There are a large number of hydroxyl groups (-OH) on the surface of silicon dioxide, which can form hydrogen bonds with water molecules, promote water wetting, and prevent rainwater from forming water droplets on the surface of the repair coating after rain, and the problem of focusing and easily burning the film surface.

[0035] In other embodiments, the outer repair layer 21 is a hydrophilic layer, that is, 1% to 2% of silicon dioxide nanoparticles are added to the outer repair layer 21. The addition of silicon dioxide nanoparticles improves the toughness of the outer repair layer 21.

[0036] The soft substrate unit layer 11 is a double-layer arrangement, and the hard substrate unit layer 12 is sandwiched between the double-layer soft substrate unit layers 11. The material of the hard substrate unit layer 12 is one or more of PVC, PU and TPU recycled materials, and the material of the soft substrate unit layer 11 is TPU. Although the softness and stretchability of PVC are relatively poor compared to the other two materials, it is a low-cost synthetic material with good chemical resistance, waterproofness and flame retardancy. Therefore, sandwiching between the double-layer soft substrate unit layers can overcome its own shortcomings. The wear resistance and weather resistance of PU are improved compared to PVC, but not as good as TPU, but it has good softness and elasticity, a more comfortable feel, good tensile properties, and can withstand large deformation without being easy to break. TPU combines the high strength of plastics and the high elasticity of rubber, has excellent tensile properties and recovery, and can maintain its original shape even after multiple stretching. TPU products are softer and more durable than PVC and some PU products, and are better than PVC and PU in wear resistance, oil resistance, low temperature resistance and chemical resistance. The use of TPU recycled materials in the production of protective films not only improves resource utilization but also reduces costs.

[0037] In order to improve the firmness and processability between layers, the PUR hot melt adhesive will further react with moisture in the air after cooling to form a more stable and lasting chemical bond. This characteristic makes its bonding effect stronger over time. Therefore, the soft substrate unit layer 11 and the hard substrate unit layer 12 are connected by the polyurethane hot melt adhesive layer 10.

[0038] In order to increase the contact area between the layers, in some embodiments, at least one surface of the hard substrate unit layer 12 is matched with the soft substrate unit layer 11 in a concave-convex manner. When the protective film is bent, the grooves of the hard substrate unit layer are microscopically gathered, and the corresponding protrusions on the soft substrate unit layer 11 are compressed, thereby improving the bending resistance of the hard substrate unit layer 12. The soft substrate unit layer 11 and the hard substrate unit layer 12 are connected by hot pressing.

[0039] In some other embodiments, at least one surface of the hard substrate unit layer 12 matches the polyurethane hot melt adhesive layer 10 in a concave-convex manner.

[0040] In order to improve the bonding stability and durability of the protective film, the material of the bonding layer 3 is a high temperature resistant acrylic adhesive.

[0041] In order to prevent the repair coating from being damaged during transportation and cutting, a peeling protective layer 5 is provided on the surface of the repair coating 2 away from the substrate layer 1, and a PET release film 6 is provided on the surface of the adhesive layer 3 away from the substrate layer 1. Further, the peeling protective layer 5 includes a PET substrate layer 51 and an elastic buffer layer 50. The provision of the elastic buffer layer 50 improves the toughness and impact resistance of the peeling protective layer 5, can eliminate part of the impact force, and play a buffering role. Furthermore, the material of the elastic buffer layer 50 is polyethylene.

[0042] In order to improve the pasting efficiency of the protective film, the adhesive layer has a venting effect to effectively prevent the appearance of bubbles during the film pasting process, thereby improving the appearance and performance of the protective film. One surface of the adhesive layer 3 is connected to the substrate layer 1, and the other surface is provided with a concave-convex surface, which is matched with the PET release film 6.

[0043] The thickness of the repair coating 2 is 12-18 μm, the thickness of the substrate layer 1 is 100-500 μm, the thickness of the adhesive layer 3 is 20-30 μm, the thickness of the peeling protection layer 5 is 35-50 μm, and the thickness of the PET release film 6 is 50-200 μm.

[0044] Example 1

[0045] like Figure 1 As shown, the metal part paint protection film of Example 1 includes a peeling protection layer 5, a repair coating 2, a substrate layer 1, an adhesive layer 3 and a PET release film 6 stacked in sequence from the outside to the inside, wherein the repair coating 2 includes an outer repair layer 21 and an inner repair layer 22 with increasing thicknesses, the hardness of the inner repair layer 22 is less than the hardness of the outer repair layer 21, and the substrate layer 1 includes a hard substrate unit layer 12 and a soft substrate unit layer 11, the soft substrate unit layer 11 is connected to the adhesive layer 3, the material of the hard substrate unit layer 12 is PU, and the material of the soft substrate unit layer 11 is TPU. The outer repair layer 21 is a hydrophilic layer. The hard substrate unit layer 12 and the soft substrate unit layer 11 are both concave-convex matched.

[0046] The peeling protection layer 5 includes a PET substrate layer 51 , an elastic buffer layer 50 , a PET substrate layer 51 and a release layer 52 which are stacked in sequence, and the release layer 52 is connected to the outer repair layer 21 .

[0047] Example 2

[0048] like Figure 2 As shown, Example 2 is based on Example 1, except that the soft substrate unit layer 11 is a double-layer arrangement, the hard substrate unit layer 12 is sandwiched between the double-layer soft substrate unit layers 11, the hard substrate unit layer 12 is made of PVC, and the soft substrate unit layer 11 is made of TPU. The soft substrate unit layer 11 and the hard substrate unit layer 12 are connected by a polyurethane hot melt adhesive layer 10, and the hard substrate unit layer 12 is matched with the polyurethane hot melt adhesive layer 10 in a concave-convex manner.

[0049] Example 3

[0050] like Figure 3 As shown, Example 3 is based on Example 1, with the difference that a hydrophilic layer 4 is provided on the surface of the outer repair layer 21 away from the inner repair layer 22 .

[0051] The product of the embodiment had no creases after being bent 20,000 times.

[0052] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A metal paint protective film, comprising: A substrate layer having a first surface and a second surface opposite to each other along the film thickness; A repair coating is disposed on the first surface; an adhesive layer, disposed on the second surface; Characterized in that the repair coating comprises an outer repair layer and an inner repair layer with successively increasing thicknesses, and the hardness of the inner repair layer is less than the hardness of the outer repair layer; The substrate layer includes a hard substrate unit layer and a soft substrate unit layer, and the soft substrate unit layer is connected to the adhesive layer.

2. The metal paint protection film according to claim 1, characterized in that: A hydrophilic layer is arranged on the surface of the outer repair layer away from the inner repair layer, or the outer repair layer is a hydrophilic layer.

3. The metal paint protection film according to claim 1, characterized in that: The soft substrate unit layer is a double-layer arrangement, the hard substrate unit layer is sandwiched between the double-layer soft substrate unit layers, the material of the hard substrate unit layer is one of PVC, PU and TPU recycled materials, and the material of the soft substrate unit layer is TPU.

4. The metal paint protection film according to claim 3, characterized in that: The soft substrate unit layer and the hard substrate unit layer are connected by a polyurethane hot melt adhesive layer.

5. The metal paint protection film according to claim 4, characterized in that: At least one surface of the hard substrate unit layer is matched with the soft substrate unit layer in a concave-convex manner, or matched with the polyurethane hot melt adhesive layer in a concave-convex manner.

6. The metal paint protection film according to claim 1, characterized in that: The material of the bonding layer is high temperature resistant acrylic adhesive.

7. The metal paint protection film according to claim 1, characterized in that: A peeling protective layer is disposed on the surface of the repair coating away from the substrate layer, and a PET release film is disposed on the surface of the adhesive layer away from the substrate layer.

8. The metal paint protection film according to claim 7, characterized in that: The peeling protection layer comprises a PET substrate layer and an elastic buffer layer.

9. The metal paint protection film according to claim 7, characterized in that: One surface of the adhesive layer is connected to the base material layer, and the other surface is provided with a concave-convex surface, and the concave-convex surface is matched with the PET release film.

10. The metal paint protection film according to claim 1, characterized in that: The thickness of the repair coating is 12-18 μm, the thickness of the substrate layer is 100-500 μm, and the thickness of the adhesive layer is 20-30 μm.

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