KR101209194B1 - Release film for automobile paint protection film - Google Patents

Abstract

The present invention is a structure of a release film for automobile film protective film (PPF) consisting of a base film layer and a release layer, characterized in that the base film layer is a polyester base film having a two-layer structure of A layer / B layer It relates to a release film for PPF.
The release film for PPF of the present invention adopts a polyester film material in place of the paper used as the base film layer, thereby ensuring moisture resistance, no dust generation, and optimizing the surface roughness of each layer. Due to the two-layer structure, by providing blocking resistance with the base film of the automotive film protection film (PPF), it is possible to solve the problem of the release film using a conventional polymer film as the base film layer. Furthermore, when the release film for PPF of the present invention is used by laminating the pressure-sensitive adhesive layer of the PPF, there is no swelling and deformation of the release film due to moisture, and the PPF can be preserved like a circular shape even when exposed to high humidity for a long time. Blocking of the liver is suppressed to improve workability and effectively prevent damage to the PPF.

Description

Release film for car paint protection film {RELEASE FILM FOR AUTOMOBILE PAINT PROTECTION FILM}

The present invention relates to a release film for an automobile coating protective film, and more particularly, in a release film for an automotive coating protective film composed of a base film layer and a release layer, wherein the base film layer has a double layer structure of A layer / B layer. The present invention relates to a release film for automotive coating films that has a moisture resistance, is free of dust, and has a blocking resistance when used in combination with an adhesive layer of an automotive coating film by using a polyester base film.

Paint protection film (hereinafter referred to as "PPF") is widely used for the purpose of protecting the painted surface from damage caused by sand, gravel, etc., which hits the painted surface of the vehicle while driving.

PPF is a structure in which a pressure-sensitive adhesive is applied to a base film having excellent impact resistance to form a pressure-sensitive adhesive layer. The PPF is directly attached to a paint surface of a vehicle to prevent damage to the paint surface by debris. On the other hand, when the painted surface is damaged by debris, the peeled off surface can be easily peeled off and rebuilt, so that the quality of the painted surface can be maintained in the same state as when the vehicle is shipped.

In general, PPF is a polyurethane film having excellent impact resistance and easy to be stretched when heated, using a polyurethane film having excellent workability as a base film, and applying a rubber-based pressure-sensitive adhesive to form a pressure-sensitive adhesive layer thereon, and detaching from the pressure-sensitive adhesive layer. Attach this easy release film. The release film serves as a protective paper of PPF in addition to the purpose of easy detachment.

The release film for PPF has a structure using a paper or a polymer film as a base material, and having a release layer on one side of the base material, and classified into a release paper or a release film according to the base material.

As a release film for PPF, when the release film is used, the workability is greatly increased because the so-called 'blocking' phenomenon occurs when the substrate surface of the release film and the substrate surface of the PPF adhere to each other during winding (rolling work) after lamination with PPF. It worsens and, in severe cases, causes deformation, such as increased PPF during work.

For this reason, release paper is mainly used as a release film for PPF in commercialized products. However, when the release paper is used as a release film for PPF, the above blocking problem can be solved. However, in the environment where the paper is vulnerable to moisture and exposed to high humidity for a long time such as in rainy season, the release paper expands and deforms due to moisture. By causing the layer to bend, there is a disadvantage that the quality of the PPF or the defect is caused. In addition, when dust is generated from the release paper, it may be buried in the adhesive of the PPF.

An object of the present invention is to provide a release film for PPF consisting of a co-extruded polyester base film layer and a release layer.

It is another object of the present invention to provide a release film for PPF, which has high blocking resistance and moisture resistance and is free of dust, thereby improving workability.

In order to achieve the above object, the present invention provides a release film for PPF composed of a co-extruded polyester base film layer and a release layer.

More specifically, in the release film for an automotive coating film comprising a base film layer and a release layer, the release film for PPF of the present invention is a polyester substrate co-extruded in a two-layer structure of the layer A / B layer of the base film layer It is a film.

More preferably, in the release film for PPF of the present invention, the layer A of the polyester base film has a two-dimensional center line average roughness of 0.1 μm or less, and the layer B of the polyester base film has a two-dimensional center line average roughness of 1 to 10. It is designed to be μm.

At this time, the thickness of the polyester base film in the release film for PPF of the present invention is 20 to 100㎛.

In the release film for PPF of the present invention, the release layer is laminated on the surface of the A layer of the polyester base film, wherein the release layer is characterized in that the polymeric silicone.

The release film for PPF of the present invention is laminated on the pressure-sensitive adhesive layer of the automobile coating film protective film, laminated on the pressure-sensitive adhesive layer to maintain the blocking resistance after winding, by adopting a polyester base film, moisture resistance is ensured. In addition, the release film for PPF of the present invention has no dust generation, there is no contamination of the PPF and can lower the defective rate in the process.

As described above, in the present invention, the release film for PPF uses a polyester film coextruded with the base film layer in the structure of the base film layer and the release layer, so that there is no moisture resistance and dust generation. This can solve the problem of the release film employed.

In addition, the release film for PPF of the present invention has a two-layer structure of the base film layer of the A layer / B layer, by optimizing the surface roughness of each layer, to solve the blocking problem caused by the release film employing the conventional polymer film. can do.

Thus, when the release film for PPF of the present invention is used by laminating the pressure-sensitive adhesive layer of the PPF, there is no swelling and deformation of the release film due to moisture, and the PPF can be preserved in a circular shape even when exposed to high humidity for a long time. In addition, when winding up after lamination with PPF, by minimizing the contact area between the surface of the layer B of the polyester base film and the surface of the urethane base film of the PPF which is in contact with the PPF, blocking occurs and workability is improved, and damage to the PPF can be effectively prevented. .

1 is a schematic cross-sectional view of the base film layer in the release film for PPF of the present invention,
2 is a schematic cross-sectional view of the entire layer structure in the release film for PPF of the present invention.

Hereinafter, the present invention will be described in more detail.

The present invention provides a release film for PPF, wherein the release film for PPF consisting of a base film layer and a release layer, wherein the base film layer is a polyester base film coextruded with a double layer structure of A layer / B layer.

In the release film for PPF of the present invention, by adopting a polyester base film as the base film layer, it is possible to secure moisture resistance and eliminate dust generation rate, compared to the case of using conventional paper.

Furthermore, the base film layer made of the polyester base film co-extruded in the release film for PPF of the present invention has a two-layer structure of A layer / B layer, and the two-dimensional centerline average roughness value (Ra) of the interlayer is designed differently It features.

At this time, in the base film layer of the release film for PPF of the present invention, the two-dimensional center line average roughness of the A layer (2) of the polyester base film is 0.1㎛ or less, the two-dimensional of the B layer (1) of the polyester base film The center line average roughness is designed to be 1 to 10 µm.

At this time, when the average roughness value Ra of the A layer 2 of the polyester base film exceeds 0.1 μm, when the release layer is applied on the A layer, the release liquid is released due to the high surface roughness of the base film. Uneven coating may reduce the peelability of the release film for PPF. As a result, the workability worsens and in severe cases it may not be peeled off or may cause damage such as sagging, tearing or warping of the PPF, and noise (zip) may occur when the PPF is peeled off.

In addition, the average roughness value (Ra) of the B layer (1) of the polyester base film is preferably 1 to 10㎛, and less than 1㎛, B of the polyester base film in the release film at the time of winding after lamination with PPF The contact area between the layer surface and the base film of the PPF becomes wider, and blocking occurs, resulting in poor workability. On the other hand, when the average roughness value Ra of the B layer 1 of the polyester base film exceeds 10 µm, the high surface roughness of the B layer affects the A layer and thus the surface roughness of the A layer is in the above preferred range. You get out. In this case, when the polyester base film is wound, the rough surface of the B layer 1 of the polyester base film abuts the A layer 2, causing scratches on the surface of the A layer 2, thereby improving the quality of the polyester film. Worse

In this case, in the polyester base film, the average roughness value (Ra) of the two-layer structure of the layer A / B is fixed to inorganic particles such as silica or calcium carbonate, which are not compatible with the polyester, inside the polyester base film. It can be adjusted by containing a component. However, the release film for PPF of the present invention has the purpose of optimizing the average roughness (Ra) value between each layer of the layer A / B of the polyester base film in order to realize the desired physical properties when applied to the PPF, each layer The method of adjusting the average roughness value Ra of the well-known technique.

The release film for PPF of the present invention requires a thickness control of a polyester base film in order to realize desired properties when applied to PPF. Thus, the thickness of the polyester base film is preferably 20㎛ to 100㎛, if the thickness is less than 20㎛, particles contained in order to adjust the Ra of the B layer (1) of the polyester base film A layer ( By affecting 2), Ra of the A layer 2 is out of the above preferable range. On the other hand, when the thickness exceeds 100㎛, the release film is heavy and thick, the economical efficiency is lowered and the commerciality is inferior.

Polyester base film of the present invention is produced by a co-extrusion method, specifically, the co-extrusion method is a specially designed die after melting the polymers of different components, respectively through a separate path so that each of the molten polymers do not mix with each other By extrusion through, it is possible to obtain a polymer film having a two-layer or more layer structure consisting of polymers of different components. The coextrusion method is carried out by a method known in the art to be omitted a detailed description.

In the release film for PPF of the present invention, the release layer 3 is laminated on the surface of the A layer 2 of the polyester base film, and the release layer 3 is cured by applying and releasing a release agent mainly containing polymer silicone. Form.

As the release agent, a solvent type, a solventless type, or an emulsion type silicone release agent may be used, and the method of forming the release layer may be performed without particular limitation in the known art.

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

Example 1 Release Film 1

A polyester chip (layer A) containing 1% by weight of silica particles having an average particle size of 1 µm and a polyester chip (layer B) containing 5% by weight of silica particles having an average particle size of 10 µm are melted and After extrusion to prepare an unstretched polyester sheet, a biaxially stretched at 190 ° C. to prepare a polyester base film having an A layer / B layer structure having a thickness of 30 μm.

In addition, a silicone release liquid consisting of 1% by weight of a silicone compound containing polydimethylsiloxane and a hydrogensilane compound, 0.05% by weight of a platinum catalyst mixture, and a residual amount of toluene is uniformly applied to the surface of the layer A of the polyester base film using a Mayer bar. After drying at 150 ° C. for 30 seconds, a release film having a release layer having a thickness of 0.05 μm was prepared.

Example 2 Release Film Preparation 2

Co-extrusion of the polyester chip (A layer) containing 5 wt% of silica particles having an average particle size of 1 μm and the polyester chip (layer B) containing 10 wt% of the silica particles having an average particle size of 10 μm, respectively. To prepare an unstretched polyester sheet, and then biaxially stretch at 190 ° C. to prepare a polyester base film having an A layer / B layer structure having a thickness of 25 μm.

Then, the release layer forming process on the A layer of the polyester base film was performed in the same manner as in Example 1, to prepare a release film having a release layer.

Example 3 Release Film 3

A release film having a release layer was prepared in the same manner as in Example 2, except that 15 wt% of the particle content of the polyester chip for forming the B layer was used.

Example 4 Manufacturing Release Film 4

Using the same polyester chip as in Example 2, to prepare a polyester base film of the A layer / B layer structure, except that the thickness of the sheet before stretching to 90㎛, the same as in Example 2 It was carried out by the method to prepare a release film on which a release layer was formed.

≪ Comparative Example 1 &

A release film having a release layer was prepared in the same manner as in Example 2, except that 10 wt% of the particle content of the A-layer forming polyester chip was used.

Comparative Example 2

A release film having a release layer was prepared in the same manner as in Example 2, except that 3 wt% of the particle content of the polyester chip for forming the B layer was used.

≪ Comparative Example 3 &

A release film having a release layer was prepared in the same manner as in Example 2, except that 20 wt% of the particle content of the B-layer forming polyester chip was used.

≪ Comparative Example 4 &

Using the same polyester chip as in Example 2, to prepare a polyester base film of the A layer / B layer structure, except that the thickness of the sheet before stretching to 15㎛, the same as in Example 2 It was carried out by the method to prepare a release film on which a release layer was formed.

≪ Comparative Example 5 &

Release papers of commercialized PPF (3M Scotchgard) were separated from PPF and evaluated as a comparative group.

The structure of the base films of Examples 1 to 4 and Comparative Examples 1 to 5 prepared above are shown in Table 1 below.

Experimental Example 1 Evaluation of Physical Properties of Release Film

1. Surface roughness (Ra) measurement

With respect to the release film characterized by the polyester base film of the A-layer / B-layer structure produced in Examples 1 to 4 and Comparative Examples 1 to 4, the surface roughness (Ra) value of each layer was determined by two-dimensional contact roughness. It measured using the meter. Each measurement was carried out three times to calculate the average value and the results are shown in Table 2 below.

2. Blocking evaluation

The release films of Examples 1 to 4 and Comparative Examples 1 to 5 were laminated with a roll film of a vehicle protective film (PPF) manufactured by a known method (Korean Patent Publication No. 2009-0012460), and then wound at room temperature. Aged for 3 days. In the process of unrolling and unrolling again, blocking occurs and the roll does not naturally unwind, but if it takes a lot of effort to unroll the roll, it is referred to as "bad", otherwise "good".

3. Peelability Evaluation

After the release films of Examples 1 to 4 and Comparative Examples 1 to 5 were laminated with PPF, aged at room temperature for 3 days, and then the peelability when the release film was peeled off was evaluated. When the peelability between the release film and the PPF is insufficient and the PPF or the release film is stretched or torn during peeling, or when the PPF adhesive is transferred to the release film, or when noise (zip) occurs, "Bad" and the case where peeling well occurs without deformation of the PPF is described as "good".

4. Dust generation

After cutting the release film of the said Examples 1-4 and Comparative Examples 1-5 with the knife, after attaching a transparent cellophane tape to a cut surface, it peeled off again and observed visually whether the tape adhered to the dust.

As a result, when a line due to dust is observed on the adhesive surface of the transparent cellophane tape, it is marked as "bad", otherwise it is marked as "good".

5. Moisture resistance evaluation

The release films of Examples 1 to 4 and Comparative Examples 1 to 5 were placed in a thermo-hygrostat to evaluate moisture resistance. Each sample was stored for one week at 25 ° C and 90% humidity in a state of lamination with PPF. After one week, the release film was visually observed to see if "swelling", distortion, and wrinkles were observed. Without the same appearance as before aging was marked as "good".

The physical property evaluation results are shown in Table 2 below.

As can be seen from Table 2, the release film of Examples 1 to 4 showed good evaluation results in terms of blocking evaluation, peeling, dust generation and moisture resistance. On the other hand, in the case of a release paper (comparative example 5) of a commercial product, it is impossible to use the exposure for a long time at high humidity due to poor moisture resistance, and dust is generated on the adhesive surface, causing contamination to the PPF. In addition, the results of evaluation of physical properties using the release films of Comparative Examples 1 to 4 did not simultaneously satisfy the evaluation of the blocking, peeling, dust generation, and moisture resistance. From these results, the physical properties of the release film for PPF of the present invention depends on whether the surface roughness (Ra) value of each layer constituting the polyester base film of the A layer / B layer structure, or of the polyester base film The physical properties of the release film depended on the thickness, and the results of Table 2 suggest an optimal range of surface roughness (Ra) values of the substrate A layer and the substrate B layer and an optimization range of the thickness of the polyester substrate film.

As described above, the present invention is characterized by a polyester base film having a two-layer structure of the layer A / B, and provided an improved release film for PPF formed a release layer on the base film.

The release film for PPF of the present invention replaces the polyester film instead of the conventional paper with respect to the base film layer, so that there is no moisture resistance and dust generation, and the base film layer has a structure of A layer / B layer having different surface roughness. By forming, by minimizing the contact area between the base film of the layer B and the polyurethane base film of the PPF even when winding up after lamination with PPF, it is possible to improve the workability without blocking occurs.

Thus, when the release film for PPF of the present invention is used by laminating the pressure-sensitive adhesive layer of the PPF, there is no swelling and deformation of the release film due to moisture, and the PPF can be preserved as a circular shape even after prolonged exposure at high humidity. The occurrence of blocking between the substrates is suppressed to improve workability and effectively prevent damage to the PPF.

While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined by the appended claims.

1: Polyester base film B layer
2: polyester base film A layer
3: release layer

Claims (5)

In the release film for automotive coating film comprising a base film and a release layer,
The base film is a polyester base film having a two-layer structure of the A-layer / B-layer co-extruded, the thickness of the base film is 20 to 100㎛, the two-dimensional centerline average roughness of the A layer is 0.1㎛ or less, Release film for automotive coating film (PPF), characterized in that the two-dimensional center line average roughness of the B layer has a 1 to 10㎛, the release layer is laminated on the surface of the A layer.
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