KR100720373B1 - The manufacturing method of a protective film for surface of mechanical goods - Google Patents

Abstract

The present invention multilayers the structure of the surface protection film used for the surface protection of materials such as metal plates and glass for flat panel displays and various industrial equipment, and the nonwoven fabric layer as a release layer on one side and an adhesive layer on the other side. When the extrusion coating layer is formed, it is adhered to various materials to provide the surface protection as well as the releasability and separation property. In the method of manufacturing the surface protective film (A) for protecting the surface of various materials by ensuring release property and separability without providing a cushioning material such as iii), a basis weight of 16 g / m 2 having moisture-proofing and air-permeating function. The corona treatment is performed to the film body 4 used as the uniaxially stretched polyethylene-based film, and the basis weight is 16-18 g / m 2, polypropylene-based spun The nonwoven fabric layer (1) of thermal bonding method to 140 ℃ to make a bonded fabric, the melt flow index 12-15g / 10 minutes, the vinyl acetate content of 15-18% by weight in ethylene vinyl acetate air It is a manufacturing method of the film for protecting the surface of a substance characterized in that the coating is coated with a coating amount of 14 to 16 g / m 2 while maintaining the extrusion temperature at 230 ° C. and the cooling temperature at 10 ° C.

Surface protection, film body, adhesive layer, nonwoven fabric, extrusion coating

Description

The manufacturing method of a protective film for surface of mechanical goods}

1 is a cross-sectional view of a representative example of a film made by the present invention

2 is a cross-sectional view of another example of a film produced by the present invention.

Figure 3 is an extrusion coating layer forming process of the film according to the present invention

 Explanation of symbols on the main parts of the drawings

1: nonwoven fabric layer 2: extrusion coating layer 3: adhesive layer

4: film body

The present invention relates to a method for producing a film for protecting the surface of a substrate, and more specifically, to one side by multilayering the structure of the surface protection film used for surface protection of various industrial equipment including metal plates and glass for flat panel displays. The nonwoven fabric layer is formed as a release layer, and the extrusion coating layer is formed as an adhesive layer on the other side, thereby adhering to various equipments to provide not only surface protection but also releasability and separability. In this case, the releasability and separability are ensured without installing a cushioning material such as a separate sheet between the laminated surface and the surface.

In general, in the case of a protective film used to protect the surface of various industrial equipment and consumer goods, it is common that a separate self-adhesive treatment is performed on the film so that the protective film itself does not have adhesiveness and thus has self adhesiveness.

Such self-adhesive method is known, such as coating method of the pressure-sensitive adhesive, coextrusion method of the adhesive polymer, etc., the coating method of the pressure-sensitive adhesive, the coating component contaminates the surface of the adherend, sensitive to the surrounding environment changes the environment The cohesion of the cohesive polymer is severe, and the coextrusion method of the cohesive polymer decreases the working efficiency as the content of the cohesive component in the cohesive polymer increases, resulting in peeling from the film body, and due to the limitation of the coextrusion structure. It is true that it is difficult to achieve the required level of self-adhesion.

In addition, it is known to give unevenness through embossing to a surface of a protective film or to perform a separate release material treatment such as silicon when the release property and separation property between the surfaces in contact with each other are not secured. Insufficient releasability and separability in the working efficiency, or a separate material having a releasability between the contact surface and the surface that requires the release function, that is, the hassle that has to sandwich the interstitial exists, when using the surface protective film Depending on the intended use, it is accompanied by a separate treatment procedure to have tackiness and / or release property, and as a result, the manufacturing process of the product to which the surface protective film is applied is complicated, and the efficiency thereof is lowered. There was no problem.

Therefore, the present invention has a release function on one side of the surface protection film, and the film to have a self-adhesive function on the other side in order to solve all the problems with the conventional surface protection film that does not have the proper adhesiveness and mold release property as described above Since the nonwoven fabric and the extrusion coating layer are formed on both sides of the main body, there is no need for a separate adhesive treatment to the protective film, as well as a change in adhesive force due to environmental changes does not occur, and contamination of the adherend due to the adhesive can be prevented. Since the release treatment process can be omitted, it is possible to simplify the manufacturing process of various substrates to which the surface protection film is applied, and to provide a manufacturing method of the surface protection film for improving the production efficiency by lowering the manufacturing cost.

In order to achieve the above object, the method for producing a surface protection film according to the present invention is a method for producing a surface protection film (A) for protecting the surface of various materials, the basis weight of 16 g / ㎡ having moisture-proof, air-permeable function The corona treatment is performed to the film body (4) which becomes a uniaxially stretched polyethylene film, and it heat-bonds at 140 degreeC with the polypropylene-type spunbond type nonwoven fabric layer (1) of 16-18 g / m <2>, and bonds fabric Ethylene vinyl acetate copolymer having a melt flow index of 12 to 16 g / 10 minutes and a vinyl acetate content of 15 to 18 wt% in the present bonded fabric while maintaining an extrusion temperature of 230 ° C. and a cooling temperature of 10 ° C. It characterized in that the extrusion coating layer (2) is formed by coating with ~ 16g / ㎡.

In addition, the manufacturing method of the film (A) for protecting the surface of the present invention is characterized in that an extrusion coating layer (2) as a direct adhesive layer is formed on one side of the nonwoven fabric layer (1) as a release material without using a film body.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

1 is a partially enlarged cross-sectional view showing the configuration of a representative example of the surface protection film produced by the present invention, Figure 2 is a cross-sectional view showing the configuration of another example of the surface protection film produced by the present invention, Figure 3 is a process diagram showing the process of forming an extrusion coating layer of the production method according to the present invention, the configuration is largely composed of a nonwoven fabric layer 1 and an extrusion coating layer (2).

The nonwoven fabric layer 1 provided to impart a release function is prepared by producing short fibers or filament fibers using polyolefin-based and polyethylene phthalate as raw materials, and then bonded to each other by physical or chemical methods to impart morphological stability. The melt blown or spunbond method using polypropylene resin is preferably applied.

In addition, embossing can be performed to further improve the release property and separability of the nonwoven fabric constituting the release layer, and the embossed area is 5 to 30 (%) of the total nonwoven area, preferably 10 to 15 ( %) Is good.

The extruded coating layer 2 as the adhesive layer has a melt flow index of 0.5 to 20.0 (g / 10 minutes), preferably 10.0 to 20.0 (g / 10 minutes), and a vinyl acetate content of 5 to 28 (wt%), preferably 10-20 (wt%) ethylene vinyl acetate copolymer resin by extrusion coating at a coating amount of 5-30 (g / m 2), preferably 10-20 (g / m 2) It is to give a self adhesive function.

If the melt flow index of the ethylene vinyl acetate copolymer is 0.5 (g / 10 min) or less, the flowability of the molten resin is poor and uneven, so that coating is difficult. If the melt flow index is 20.0 (g / 10 min) or more, the molten resin Due to its excessive flowability, smooth coating flows into the liquid before it is fused and solidified onto the bonded fabric, making it difficult to achieve a smooth coating.

In addition, when the vinyl acetate content of the ethylene vinyl acetate copolymer is 5% by weight or less, the self-adhesive function may not be expressed, and when 28% by weight or more, the self-adhesiveness may be excessive, resulting in adhesion to the surface of the protective substrate, thereby damaging the protective substrate. Will result.

In addition, when the coating amount of the ethylene vinyl acetate copolymer is 5 (g / ㎡) or less, there is a problem in securing the uniformity of the coating amount, and the self-adhesive function cannot be expressed, and when the coating amount is 30 (g / ㎡) or more The self-adhesive force becomes excessive, resulting in a dysfunction which damages the protective base material, or the self-weight becomes high, so that the required self-adhesive function cannot be expressed.

The film body 4 is calendered by using polypropylene, polyethylene, polyethylene terephthalate, polystyrene, nylon, polyvinyl chloride, polyvinylidene chloride, polyethylene naphthalate, polyvinyl alcohol, ethylene vinyl alcohol alone or in combination. , A polymer film layer produced by applying a casting method, a uniaxial stretching method, a simultaneous biaxial stretching method (inflation method), and a sequential biaxial stretching method, and preferably the surface quality of various industrial materials and materials such as surfaces protected. In order to preserve the moisture, the film which has moisture-proof and ventilation function which made the air permeable smoothly and is waterproof is preferable.

In addition, the film body 4 is preferably subjected to corona treatment to facilitate bonding with the nonwoven fabric layer (1). The adhesive layer (3) is a layer that serves to bond the nonwoven fabric layer (1) and the film body (4) to create a single bonding fabric, the bonding method can be both thermal bonding or bonding using an adhesive.

The film applied to the surface protection of various industrial equipment, materials and consumer goods of the present invention is produced through the extrusion coating process of Figure 3, the nonwoven fabric layer 1 and the film body 4 as described above is an adhesive layer (3) Excellent adhesion to the coating of ethylene vinyl acetate copolymer while drawing the fabric in a suitable tension in the state in which the fabric composed of only the nonwoven fabric layer 1 is attached to the unwinder 5 of FIG. After the corona treatment using the corona treatment machine 6, the ethylene-vinyl acetate copolymer resin was melt-extruded at a temperature of 200 to 300 (° C), preferably 230 to 260 (° C). It is coated on the fabric through it, and it is cooled to 3 to 50 (° C.), preferably 10 to 25 (° C.) with a cast roll (9) and finally wound up with a rewinder (10) to complete the manufacture of the surface protection film as a finished product. do.

If the melting temperature is 200 (℃) or less during extrusion coating of ethylene vinyl acetate copolymer, there is a problem in melting the resin. If it is 300 (℃) or higher, the vinyl acetate of the ethylene vinyl acetate copolymer is thermally decomposed to carbonize the resin. And deterioration problem.

In addition, when the temperature of the cast roll 9 is 3 (° C.) or less, the crystallinity of the ethylene vinyl acetate copolymer resin becomes high, and thus self-adhesive function is not expressed. When the temperature of the cast roll 9 is 50 ° C. or higher, excessive adhesion of the ethylene vinyl acetate copolymer is achieved. Due to this close contact with the cast roll there is a problem in the coating operation.

Substrate surface protective film (A) according to the present invention is a combination of both the nonwoven fabric layer 1, the film body 4, the adhesive layer 3 and the extrusion coating layer (2) in order to prevent the self-adhesion function due to the weight It is preferable to be 80 g / m <2> or less.

Example 1.

Corona treatment was carried out to the film body 4 made of a uniaxially stretched polyethylene-based film having a basis weight of 16 g / m 2 having a moisture-proof and air-permeable function, and a nonwoven fabric layer 1 having a polypropylene spunbond system having a basis weight of 16 g / m 2. Bonding fabric was made by thermal bonding at 140 캜, and ethylene vinyl acetate copolymer having a melt flow index of 12 g / 10 minutes and a vinyl acetate content of 15% by weight was maintained at an extrusion temperature of 230 캜 and a cooling temperature of 10 캜. While coating the coating amount to 14g / ㎡ to form an extrusion coating layer (2) to prepare a protective film having a self-adhesive force.

As apparent from the above description, according to the method for manufacturing the surface protection film of the present invention, the nonwoven fabric layer is bonded to one side of the film body which is a polymer film to have a release function, and the other side of the film body has ethylene vinyl acetate. By forming an extruded coating layer made of a copolymer to have a self-adhesive function, the surface protection that does not require a separate sheet of paper, which requires a cumbersome processing procedure, when the surface of various industrial containers and materials is protected and laminated. The film can be manufactured to provide useful effects such as simplifying the process of using the surface protection film, improving process efficiency, and reducing the overall manufacturing cost of the material. As well as maintaining adhesiveness, changes in adhesive force due to environmental changes occur. Rather, it is possible to prevent the deposition of water pollution caused by the adhesive, and further provides a beneficial effect in terms of environmentally friendly surface protection film by supplying recyclable.

Claims (1)

In the manufacturing method of the film (A) for surface protection for protecting the surface of various objects, A nonwoven fabric layer of polypropylene spunbond method having a corona treatment to a film body 4 made of a uniaxially stretched polyethylene-based film having a basis weight of 16 g / m 2 having moisture proof and air permeability, and having a basis weight of 16-18 g / m 2 (1 ) And the bonding fabric by thermal bonding at 140 ℃, the ethylene vinyl acetate copolymer with a melt flow index of 12 ~ 16g / 10 minutes, the vinyl acetate content of 15 to 18% by weight extruded temperature 230 ℃, A coating method of 14 to 16 g / m 2 while maintaining a cooling temperature of 10 ℃ to coat the coating surface production method characterized in that the extrusion coating layer (2) is formed.

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