KR20040078010A - A Surface Protective Functional Multi-layer Film - Google Patents

Abstract

PURPOSE: A laminated functional film for protecting a surface of an adhered object is provided to achieve a self-adhesive property without the use of an adhesive agent, to exhibit little change over time in physical properties even at a temperature change, to allow the film to be easily applied on or removed from the adhered object over a wide range of temperature, and to be easily fed apiece from a stack. CONSTITUTION: The laminated functional film comprises: an inner layer directly contacting the adhered object and formed of a mixture containing 100 wt% of linear low density polyethylene(LLDPE) and 100 wt% of low density reinforced olefin; an intermediate layer formed of a mixture of 95 to 99.5 wt% of middle density polyethylene(MDPE) or high density polyethylene(HDPE) and a 0.5 to 5 wt% of a conductive polymer; and an outer layer formed of 100 wt% of low density polyethylene(LDPE), the respective layer materials being extruded in a discharge ratio of 3:4:3 in order to fabricate the film to a predetermined thickness. To avoid occurrence of blocking or to allow stacked films to be fed apiece, size-adjustable cellulose or fluff is optionally applied on the outer layer before the outer layer is solidified.

Description

A surface protective functional multi-layer film

The present invention relates to a functional film for protecting the surface of the adherend to prevent damage or contamination during transportation storage and processing of the surface of the TFT-LCD glass, polarizing plate, metal, glass, polymer sheet, and more particularly, the functional film The present invention relates to a laminated functional film for surface protection having an adhesive function so as to protect the surface of the adherend during transporting storage or processing of the adherend only by its own physical properties without applying a separate adhesive.

In general, the main reason for using functional films is TFT-LCD glass or polarizing plate, which is an essential material used in electronic information and communication equipment such as laptop liquid crystal TV, and is concerned about surface damage (scratch) during transportation storage and processing. B. Contamination by foreign matters will adversely affect the maintenance of operating characteristics, which requires a great deal of care in maintaining cleanliness. Also, the functional film for surface protection coated on the above-mentioned adherend also requires the same level of cleanliness. The functional film is coated or removed in a clean room (clean room) to prevent foreign substances from propagating to the agent.

On the other hand, in the case of the functional film to protect the surface of the adherend to maintain a certain adhesive force to maintain the adhesion ability when coated on the surface of the adherend is a widely used method to apply a solvent-type adhesive to the surface of the film, but In this case, when the film is removed from the adherend, there is a problem in that the adhesive residue remains on the adherend, and thus the use of the electronic information communication product or the clean product is gradually decreasing.

Therefore, in order to maintain adhesive strength without using adhesive at all, instead of solvent-based adhesive coating method, a polymer compound is produced by branding a polymer compound such as corona discharge treatment or ethylene vinyl acetate resin (EVA) in polyethylene as a raw material for the film. Or copolymerized materials are widely used.

The functional film for surface protection used for the above uses is a product (us patent 4895760) developed by the US Tredegar company imported and used in the case of the US Tredegar company, the adhesion between the adhesive and the film is a smooth glass plate and glass plate This vacuum adsorption principle is used to maintain the state of adhesion without falling off. The inner surface of the film adhering to the adherend has a surface roughness of 0.25 to 10 Ra, and the surface is flat and smooth. It is a laminated functional film made of a material having the same inner and outer surfaces to form a fine space to prevent the blocking of itself when the film is transported in the form of a roll.

However, as described above, in the case of a film having only the inner surface and the outer surface having the same components, the film may be coated on the adherend, or the convenience of the removal or transportation may be improved. In addition to the phenomenon that the surface is distorted due to the occurrence of contamination on the side and the embossed outer surface, and the surface resistance is formed to 10 ¹² 저항 / ㎜ without antistatic function, the film to be coated on the adhesive In this case, due to the static electricity generated in the coating process, coating defects such as peeling, curling and wrinkles are generated by the relative static electricity charging between the film and the film, and the coating roller. In the film removal process, the removal work is performed smoothly due to the remaining static electricity. Cases have not been triggered.

In addition, in the case of an adherent having a very flat surface such as a TFT-LCD glass, when the outer surface is coated with an embossed film such as the film, the degree of embossing is limited to Ra = 0.8 μm. The air bag is compressed by weight, which causes vacuum adsorption, and can only prevent anti-blocking of the adherend. As it involves difficulty in taking out sheets, it is necessary to use interlayers between the adherends for smooth transportation of the adherends. There is a problem.

The present invention is derived to solve the above problems, and as a functional film for surface protection excellent adhesion and no contamination of the adherend without using any adhesive, by reaction with the adherend despite temperature changes To provide a laminated functional film for surface protection that can be easily coated and removed on the adherend even in a wide temperature range, and there is no change in physical properties such as temporal change caused. Is there.

The present invention for achieving the above object relates to a functional film for a red surface type surface protection, the physical properties of the inner layer intermediate layer and the outer layer are different, respectively, the inner layer to maintain the physical adhesive strength with the adherend and the intermediate layer is a film The outer layer relates to a laminated functional film configured to have electrical and mechanical properties of and configured to be removable from the adherend and easy to take out sheets upon lamination.

The structure of the functional film according to the present invention as described above is composed of linear low density polyethylene (LLDPE) because of its extremely flexible plastic deformation and excellent surface smoothness, even if the contact area with the adherend has a large physical adsorption force It can exhibit sufficient adhesion ability alone and does not require a post-treatment process to enhance adhesion, so it is not necessary to introduce post-treatment facilities or chemical functional groups, and maintain homeostasis of adhesion despite temperature changes. It is because wetting can be controlled in various ways depending on the adherend by adding linear low density polyethylene or organic metal compound (Platomer) according to degree or molecular weight.

The middle layer uses medium density polyethylene (MDDPE) or high density polyethylene (HDPE) to maintain the strength of the film in order to protect the inner layer of flexible properties and to prevent wrinkles and curling during the production process. By adding 0.5 ~ 5% by weight of metal powders such as copper, carbon active, or conductive polymers such as quaternary amines, the surface resistance is greatly reduced to prevent wrinkles or adhesives of the film due to static electricity when coating or removing the adherend. To prevent damage

The outer layer is made of low density polyethylene (LDPE) so that the use of an anti-blocking agent is not necessary, and the inner layer, the middle layer and the outer layer are manufactured in a laminated type having a predetermined thickness at a discharge ratio of 3: 4: 3, and then the laminated type. Before the surface of the outer layer of the film is completely solidified, the functional film is completed in the form of attaching cellulose, such as fiber or cotton, to the outer layer in an air-blown manner through a device having a predetermined pore size. The thickness of 5-30㎛ is preferred.

Hereinafter, the present invention will be described in detail with reference to the examples, and the present invention is not limited to the examples.

Example 1 A low-density polyethylene Elite5400 (DOW company) 100% by weight and a low density reinforced olefin Affinity 1880 (DOW company) compounded by filling in the inner layer extruder, medium density polyethylene 908U (Samsung) 95-95 99.5% by weight of the quaternary amine ES7200 (More Chem) 0.5 to 5% by weight of compounding the intermediate layer and the low density polyethylene 432G (Samsung) in the outer layer and the inner layer, intermediate layer and outer layer 3: 4 A 30-micrometer-thick laminated film was produced with a discharge ratio of 3: 3.

Example 2 A 100% weight ratio of linear low density polyethylene Elite5400 (DOW company) and a 50% weight ratio of Affinity 1880 (DOW company), which is a low density reinforced olefin, were compounded in the same manner as in Example 1 and filled into an inner layer extruder. Density Polyethylene 908U (Samsung) 95 to 99.5% by weight of the quaternary amine ES7200 (More Chem) 0.5 to 5% by weight of the compounding compound in the intermediate layer and low density polyethylene 432G (Samsung) in the outer layer and then the inner layer, The intermediate layer and the outer layer were laminated with a thickness of 30 μm at a discharge ratio of 3: 4: 3.

(Comparative Example 1) A low density polyethylene 431G (Samsung Yarn) was filled in an inner layer extruder, a medium density polyethylene 908U (Samsung Yarn) was filled in an intermediate layer, and a low density polyethylene 432G (Samsung Yarn) was filled in an outer layer. A 30 μm laminated film was prepared.

Comparative Example 2 Ethyl vinyl acetate 120A (Samsung Yarn) was charged into the inner layer extruder, medium density polyethylene 908U (Samsung Yarn) was filled in the middle layer, and low density polyethylene 432G (Samsung Yarn) was filled in the outer layer. A 30 μm thick laminated film was prepared.

(Comparative Example 3) The surface protection functional film of Tredegar company according to US patent (US 4895760) was used for the experiment as it is.

The physical properties of the film was measured by the following conditions and methods for the functional film produced by the method of the embodiment according to the present invention and the comparative functional film sample prepared by the known method.

(Measuring conditions)

Adhesion: The functional films (size: 100 mm x 400 mm) prepared according to Examples and Comparative Examples were applied to TFT-LCD glass (size: 350 mm x 450 mm) as an adhesive, respectively, at 30 ° C, 40 ° C and 50 ° C. After making a sample laminated at a pressure of 2atm under the temperature condition and leaving it for 2 hours under the constant temperature and humidity conditions of 23 ℃ -60% RH, the peel force of the functional film and the adherend was measured at a speed of 300mm / min using a universal testing machine.

ㅇ Change in time: The functional film (size: 100 mm x 400 mm) prepared according to the Examples and Comparative Examples was applied to a TFT-LCD glass (size: 350 mm x 450 mm) as an adherend under a pressure of 2 atm at a temperature of 30 ° C. Laminated samples were prepared and left for 24 hours in a constant temperature and humidity condition of 40 ° C.-60% RH, and then left for 2 hours in a constant temperature and humidity condition of 23 ° C.-60% RH, followed by a 300 mm / min speed test using a universal testing machine. The peeling force of the functional film and the adherend

ㅇ Surface roughness: The roughness of the film was measured using a surface roughness sample of the functional film (100 mm x 200 mm) prepared in Examples and Comparative Examples.

ㅇ Surface resistance: Measure the surface resistance of the film using the surface resistance tester of the sample of the functional film (100mm x 100mm) prepared in Examples and Comparative Examples

On the other hand, the measurement results for the physical properties of the film samples of the Examples and Comparative Examples by the same method as shown in Table 1 below.

Table 1

As a result of comparing the Example with the Comparative Example, Example 1 according to the present invention showed that the adhesion, time-dependent change, surface roughness and surface resistance, which are physical properties that should be provided as a functional film, were the most excellent. It was found to be much better than the physical properties of the manufactured Tredegar.

Therefore, in the case of the laminated surface protective functional film manufactured by the same method as the embodiment of the present invention, in order to facilitate blocking and sheet drawing that may occur during transportation and storage, additionally, the laminated functional film may have a predetermined size on the outer layer of the laminated functional film. For protecting the finished surface by sealing the fiber in a clean room after spraying it with air-blown method through the fiber supply device that can control the size of the fiber before the outer layer of the laminated functional film is hardened. The red functional film is finally produced.

The laminated functional film for surface protection according to the present invention is excellent in that the functional film is equipped, but the manufacturing process is simple and the manufacturing cost is lower than that of the existing product, and charging is added to the intermediate layer of the functional film according to the characteristics of the adherend. Because it is possible to control the inhibitor, it is a useful invention that greatly improves the effect of maintaining the stability of the adherend because it can maintain a constant physical adhesion without chemical changes with various adherends.

Claims (4)

In the laminated functional film having self-adhesion ability, the inner layer in direct contact with the adherend includes a material mixed in a linear low density polyethylene (LLDPE) 100% weight ratio and a low density reinforced olefin 100% weight ratio; The middle layer is composed of a medium density polyethylene (MDPE) or a high density polyethylene (HDPE) 95% to 99.5% by weight of the conductive polymer material 0.5 to 5% by weight, and the outer layer is composed of low density polyethylene (LDPE) in a 100% weight ratio It is manufactured by extruding in a ratio of 3: 4: 3 to a predetermined thickness, and then depositing fibrous or fluffy, such as cellulose having a predetermined size, on the outer surface of the outer layer before the outer layer is solidified. Functional film for laminated surface protection. The antistatic agent according to claim 1, wherein the antistatic agent of the film intermediate layer is made of a metal powder such as aluminum or copper, or a quaternary amine-based and conductive polymer. The thickness of the laminated film produced by extrusion is 5-30 탆, The functional film for laminated surface protection. The layered surface protection functional film according to claim 1, wherein the size of the fiber or the fuzz such as cellulose deposited on the outer surface of the outer layer of the film is 5 to 100 µm.