KR20080114047A - Protecting film multilayer body, polarizer mlutilayered with the same and fabrication method of the polarizer - Google Patents

Abstract

A manufacturing method of a polarizer in which a protective film laminate is laminated is provided to cut down the cost of protective film laminate by simplifying structure and manufacturing processes of protective film laminate adhered in a polarizer by performing a transcription process. A protective film laminate comprises a protective film, an adhesive layer and a releasing layer. The adhesive layer is located on the single-side of the protective film. The releasing layer is located on the other single-side of the protective film. A manufacturing method of a polarizer in which the protective film laminate is laminated comprises the following steps. The polarizer is provided. The laminate for the protective film is provided. The polarizer and the adhesive layer of the protective film laminate are arranged in order to be faced each other. The protective film laminate is transferred on the polarizer and is adhered.

Description

Protective film multilayer body, polarizer ml laminated with protective film laminate, and protective film laminated method of manufacturing polarized plate laminated {the protective film multilayer body, polarizer mlutilayered with the same and fabrication method of the polarizer}

1 is a cross-sectional view showing a conventional protective film laminate.

2 is a view showing a process of manufacturing a polarizing plate in which a protective film laminate is laminated by attaching a conventional protective film laminate to a polarizing plate.

3 is a cross-sectional view showing a protective film laminate according to an embodiment of the present invention.

Figure 4 shows a cross section of the protective film laminate after being wound in accordance with an embodiment of the present invention.

5 is a view illustrating a process of manufacturing a polarizing plate in which a protective film laminate is laminated by attaching a protective film laminate according to an embodiment of the present invention to a polarizing plate.

The present invention relates to a method for manufacturing a protective film laminate, a polarizing plate laminated with a protective film laminate, and a polarizing plate laminated with a protective film laminate, and more particularly, a protective film laminate and a protective film laminate in which a release layer base film is reduced. The laminated polarizing plate and the protective film laminate relates to a method of manufacturing a laminated polarizing plate.

In general, in a liquid crystal display device, a polarizing plate positioned on the upper and lower surfaces of a liquid crystal layer has a protective layer (film) such as triacetyl cellulose on both or one side of a polarizing film (or polarizing element) formed of polyvinyl alcohol resin or the like. It is formed into a laminated integral multilayer structure through an adhesive.

Since the surface (protective layer) of the said polarizing plate is continuously exposed to the outside before and after adhere | attaching on the upper and lower surfaces of a liquid crystal layer, it becomes easy to be damaged, such as a scratch. In order to prevent this, the protective film laminate shown in FIG. 1 is attached on the protective layer (film) of the polarizing plate, and serves to protect the surface of the polarizing plate until the polarizing plate is applied to the next process.

1 is a cross-sectional view showing a conventional protective film laminate, referring to Figure 1, providing a release layer base film, forming a release layer located on the release layer base film, a release layer base film and a release layer To form a release film comprising a. A protective film is provided, and an adhesive layer is formed on the protective film to form an adhesive film including a protective film and an adhesive layer. The release film and the adhesive film are disposed such that the pressure-sensitive adhesive layer and the release layer face each other, and are then adhered to form a protective film laminate. Here, the protective film serves to support the pressure-sensitive adhesive layer.

2 is a view illustrating a process of manufacturing a polarizing plate in which a protective film laminate is laminated by attaching a conventional protective film laminate to a polarizing plate.

Referring to FIG. 2, the release film of the protective film laminate is removed by a rewinder during the adhesion process of the protective film laminate and the polarizer formed by FIG. 1, and the pressure-sensitive adhesive film and the polarizer are disposed to face each other, and then pressurized by a roll. The protective film is adhered to one surface of the polarizing plate to form a polarizing plate in which the protective film laminating agent is laminated.

However, the conventional protective film laminate adhered to the polarizing plate by performing the transfer process is a process of forming a release film, a process of forming an adhesive film, and a process of adhering a release film and an adhesive film, that is, a three-step process. This complicated problem arises. In addition, when performing the process of the protective film laminate is adhered to the polarizing plate, there is a problem that the process of removing the release film is added. The addition of a process for removing the release film complicates the process, increases the processing time, increases the manufacturing cost, and causes a problem of treating waste. In addition, when the protective film laminate is adhered to the laminated polarizing plate is also a problem that the manufacturing cost of the protective film laminate due to unnecessary release film is increased.

Therefore, to solve this problem, a new protective film laminate Development is required.

An object of the present invention is to simplify the structure and manufacturing process of the protective film laminate adhered to the polarizing plate by performing the transfer process to realize the low cost of the protective film laminate. In addition, when the protective film laminate is adhered to the polarizing plate, the process is simplified to reduce the manufacturing cost and processing time, waste-free protective film laminate, a protective film laminate laminated polarizer and a protective film laminate laminated It is to provide a method for producing a polarizing plate.

The present invention is a protective film; An adhesive layer located on one surface of the protective film; And it relates to a protective film laminate comprising a release layer located on the other side of the protective film.

In addition, the present invention is a polarizing plate; And a protective film laminate disposed on the polarizing plate and including an adhesive layer, a protective film positioned on the adhesive layer, and a release layer disposed on the protective film. will be.

In addition, the present invention provides a polarizing plate, and provides the protective film laminate, the polarizing plate and the pressure-sensitive adhesive layer of the protective film laminate is disposed facing each other, the protective film laminated body on the polarizing plate to adhere the adhesive It relates to a method of manufacturing a polarizing plate laminated protective film, characterized in that.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to describe the present invention in more detail. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. In the figures, where a layer is said to be "on" another layer or substrate, it may be formed directly on the other layer or substrate, or a third layer may be interposed therebetween. Like numbers refer to like elements throughout the specification.

3 is a cross-sectional view of a protective film laminate according to an embodiment of the present invention.

Referring to FIG. 3, the protective film laminate of the present invention includes a protective film, a release layer located on one surface of the protective film, and an adhesive layer located on the other side of the protective film.

The protective film protects the polarizing plate, serves to reinforce the durability, moisture resistance and mechanical strength of the polarizing plate, and also serves to support the protective film stack. The protective film is not particularly limited as long as it is an optical film conventionally used in the field of the present invention. For example, polyester, polyethylene, polybutylene, triacetyl cellulose, polycarbonate, polyacryl, polyepoxy, polypropylene, polystyrene And the like can be used. As the protective film, polyester having high transparency and excellent productivity and processability may be most preferably used. In addition, polyethylene terephthalate and polyethylene naphthalate, which are excellent in heat resistance and easy to release silicone on the surface, may be used as the polyethylene, and polybutylene terephthalate, which is inexpensive, may be used as the polybutylene. Can be. In addition, the polyester film uniaxially or biaxially stretched may be used as the polyester. The material of the above-mentioned protective film may be used alone, or may be used by mixing two or more kinds, and the above-mentioned film may be laminated in multiple layers.

It is preferable that the thickness of the said protective film is 10-100 micrometers. If the thickness of the protective film is less than 10㎛, can not perform a function as a protective film, if it exceeds 100㎛, handling is not easy during the manufacturing process, the problem arises that the manufacturing cost is increased.

The release layer located on one surface of the protective film serves to protect the adhesive layer when the protective film laminate of the present invention is wound. In addition, when the protective film laminate of the present invention is attached to the polarizing plate, it is located on the protective film serves to improve the antifouling property against the adhesion of dust or foreign matter. It is preferable that it is formed of a silicone resin for curing excellent in peelability to the protective film. Although it does not specifically limit as said curable silicone resin, For example, a condensation reaction type, an addition reaction type, an ultraviolet curing type, an electron beam curing type silicone resin, and the silicone resin which can carry out heat and ultraviolet curing etc. can be used. Considering the heat resistance of the protective film, it is preferable to use an addition reaction type silicone resin that is cured at a relatively low temperature among the silicone resins. When apply | coating and hardening an addition reaction type silicone resin to the said protective film which is a monoaxially stretched polyester film, it is preferable to dry and harden at the temperature of 130 degrees C or less especially. When dried and cured at a temperature exceeding 130 ° C., there is a problem that the protective film is thermally contracted or the orientation axis is distorted, which may cause a problem of deterioration in the foreign material inspection of the polarizing plate on which the protective film laminate is laminated. Moreover, as silicone type resin which does not apply heat, ultraviolet curing type acrylic silicone, a mermercapto group containing silicone, and an epoxy group containing silicone can also be used. In addition, the release layer may be any additive, for example, a colorant such as various resins, dyes, and pigments, an infrared reflector, an infrared absorber, an ultraviolet absorber, a heat stabilizer, an antiblocking agent, and an antioxidant within a range that does not impair properties. And the like. In addition, the peel strength of the release layer is preferably 980mN / 50mm or less.

The coating amount of the release agent used in the release layer is not particularly limited, but 0.03 to 2 g / m 2 is preferable as the solid content in consideration of peeling performance, and 0.05 to 0.4 g / m 2 is most preferred. Although the release force is different depending on the type of substrate, peeling performance may be insufficient if the coating amount is less than 0.03 g / m 2, and if it exceeds 2 g / m 2, there is a fear of contamination of the pressure-sensitive adhesive with the uncured release agent.

The release layer is coated with a silicone resin on the protective film by various methods such as gravure coating, Meyer bar coating, air knife coating, doctor knife coating, and then dried and cured by heating, heat treatment or ultraviolet irradiation. Can be formed.

The pressure-sensitive adhesive layer located on the other side of the protective film is preferably used an acrylic pressure-sensitive adhesive excellent in elastic modulus and adhesive properties. The reason is that some liquid crystal display parts such as polarizing plates are formed with minute unevenness on the surface in order to suppress the flashing of the display part. Therefore, since the pressure-sensitive adhesive layer using an acrylic pressure sensitive adhesive has excellent elasticity and softness, it is sufficiently wet and spreads on the uneven surface. This is because the occurrence of minute bubbles between the uneven surface and the pressure-sensitive adhesive layer can be reduced thereby preventing peeling of the pressure-sensitive adhesive layer.

It is preferable that it is 3 micrometers-50 micrometers, and, as for the thickness of the said adhesive layer, it is most preferable that it is 5 micrometers-50 micrometers. When the thickness is less than 3 μm, when sticking to a polarizing plate having irregularities, the adhesive is dominated by the hardness of the polyester film, which is the protective film, and the adhesive is not sufficiently adhered to the surface of the polarizing plate sufficiently, and the necessary adhesive force is not obtained. Lifting is easy to occur. When the thickness exceeds 50 μm, the adhesive force may be higher than necessary, and when the adhesive is applied and formed, it may be difficult to control the thickness or to control the curing, and further increase the manufacturing cost may occur. .

An antistatic layer may be located between the protective film and the release layer or the adhesive layer. The antistatic layer may prevent static electricity generated when the protective film laminate is laminated on the polarizing plate while unwinding, during inspection or when the protective film laminate is removed from the product, thereby preventing dust, etc., in the product. This can solve the problem of foreign matter sticking.

As the antistatic agent used to form the antistatic layer, any known one can be used as long as it does not impair the adhesive force of the pressure sensitive adhesive layer or inhibit the curing of the silicone resin used in the formation of the release layer. For example, cationic surfactants (ammonium salt, sulfonium, phosphonium), anionic activators, polyoxyethylene alkylamines, polyhydric alcohol derivatives, nonionic activators, alkylamine derivatives, alkyl phosphate amine salts, fatty acid esters, alkyls Diethanolamido, polystyrene glycol ester, amphoteric surfactant, organoboron compound, polythiophene, polyaniline, ionic functional group-containing polymer and the like can be used.

The antistatic agent may be formed by a method of knowing the polyester film. Specifically, methods such as gravure coating, Mayer bar coating, air knife coating, doctor knife coating and the like can be applied. The coating amount of the antistatic agent is not particularly limited, and may be determined in consideration of the type of antistatic agent and the antistatic performance required.

Since the protective film laminate of the present invention needs to be easily peeled off after attaching to the counterpart substrate, that is, the polarizing plate, the adhesive force of the pressure-sensitive adhesive layer to the polarizing plate is preferably 30 mN / 25 mm to 500 mN / 25 mm. In the present invention, the adhesive force 1mN / 25mm was converted to 0.1g / 25mm, 30mN / 25mm is 3g / 25mm, 500mN is 50g / 25mm. When the adhesive force of the said adhesive layer is less than 30mN / 25mm, an end may generate | occur | produce or may peel easily by a certain contact, which is not preferable. In addition, if it exceeds 500mN / 25mm it is not preferable because it is not easily peeled off in the process of peeling the protective film laminate from the polarizing plate, for example, unnecessary force is applied to the polarizing plate, which is not preferable.

Figure 4 shows a cross section of the protective film laminate after being wound in accordance with an embodiment of the present invention. In FIG. 4, although the pressure-sensitive adhesive layer is wound to be positioned inside the protective film, the pressure-sensitive adhesive layer may have a structure in which the pressure-sensitive adhesive layer is wound in a roll shape to be positioned outside the protective film.

FIG. 5 is a view illustrating a process of manufacturing a polarizing plate in which a protective film laminate is laminated by attaching a protective film laminate according to an embodiment of the present invention to a polarizing plate.

Referring to FIG. 5, by providing a polarizing plate, providing a protective film laminate according to an embodiment of the present invention, and arranging the pressure-sensitive adhesive layers of the polarizing plate and the protective film laminate to face each other and then pressing by a roll. The film laminated body forms the laminated polarizing plate.

In this invention, the polarizing film (or polarizing element) which comprises a polarizing plate is not specifically limited. Preferably, the polarizing film includes, for example, a film obtained by containing a polarizing component such as iodine or a dichroic dye in a film made of polyvinyl alcohol-based resin and stretching. The thickness of these polarizing films is not specifically limited, It can form in a normal thickness. In this case, the polyvinyl alcohol-based resin may be polyvinyl alcohol, polyvinyl formal, polyvinyl acetal, and saponified products of ethylene and vinyl acetate copolymer.

Furthermore, the polarizing plate may be formed on both surfaces or one side of the polarizing film such as cellulose-based films such as triacetyl cellulose, polycarbonate films, polyester-based films such as polyethylene terephthalate, polyethersulfone-based films, polyethylene-based films, polypropylene-based films, A protective layer (film), such as a polyolefin-based film having a cyclo-based or norbornene structure, or a polyolefin-based film such as ethylene and propylene copolymers, may be formed in a multilayered structure laminated through an adhesive. At this time, the thickness of these protective layers (film) is also not particularly limited, and may be formed to a conventional thickness. The kind of protective layer (film) provided in both surfaces of the polarizing film may be the same or different. Moreover, the polarizing plate which has functional layers, such as an antistatic layer, a high hardness layer, a low reflection layer, and an glare-proof layer, can also be used as needed.

The protective film laminate according to an embodiment of the present invention is a form in which one release layer base film is removed in comparison with a conventional protective film laminate, and has excellent cost competitiveness in terms of materials, and also compares manufacturing processes. Process of forming release film, process of forming adhesive film, process of adhering release film and adhesive film, that is, process of forming release layer on protective film and adhesive layer on protective film The process of forming a, that is, consists of two steps, so the process can be simplified.

When the protective film laminate of the present invention is adhered to the polarizing plate, there is an advantage that the removal process of the release film is unnecessary and the waste of the release film after adhesion does not occur.

In addition, when the protective film laminate according to an embodiment of the present invention is wound, there is an effect that can prevent damage to the pressure-sensitive adhesive layer. In addition, since the release layer is disposed on the surface of the polarizing plate in which the protective film laminate according to the embodiment is laminated, the antifouling property against adhesion of dust or foreign matter is also induced.

The present invention will be described in more detail with reference to examples, but the scope of the present invention is not limited by the examples.

Example 1 Preparation of Protective Film Laminate

As a protective film, Ester # K1581 (350 mm X 500 mm) having a thickness of 38 µm (trade name, manufacturer: Dongyang Spinning Co., Ltd., uniaxial lateral stretched film of polyethylene terephthalate) was provided, and on one side of the protective film, SRX-211 2 parts by weight of SRX-212 (trade name, manufacturer: Toure Dow Corning Silicon Co., Ltd.) was added as a catalyst to 100 parts by weight of (trade name, manufacturer: Toure Dow Corning Silicon Co., Ltd., an addition reaction type silicone release agent). After applying a release layer material obtained by adding 20 parts by weight of X92-128 (trade name, Shin-Etsu Chemical Co., Ltd.) as a peeling additive, using an automatic coating machine equipped with a baker applicator, the solid content was 0.2 g / m 2. , And dried in a hot air circulating oven at 110 ° C. for 60 seconds to form a release layer that is a polyester film. Further, on the opposite side of the protective film on which the release layer was formed, as an acrylic adhesive, 2-ethylhexyl acrylate as the main monomer, vinyl acetate as the comonomer, and hydroxyethyl methacrylate as the functional group-containing monomer 7: 2: The solution was polymerized using azobisisobutylonitrile as a reaction catalyst under a solvent of ethyl acetate at a ratio of 1 to prepare a pressure-sensitive adhesive polymer having a weight average molecular weight of about 430,000, and Coronate-L (trade name, 5 parts by weight of the manufacturer: Japan Polyurethane Industry Co., Ltd.) was added, and the adhesive layer was formed by coating so that the thickness after drying was 20 µm. Sealed in a sealing bag to prevent air from passing through, it was cured for 14 days in a constant temperature and humidity chamber at 25 ° C. and 50%, and rolled into a glass rod having a length of 40 cm and a diameter of 1.2 cm so that the pressure-sensitive adhesive layer was inward. , A long rod-shaped protective film laminate roll was prepared.

Test Example 1 Preparation and Evaluation of Polarizing Plate Laminated with Protective Film Laminate

While unwinding the protective film laminate obtained in Example # 1, the pressure-sensitive adhesive layer of the protective film laminate was disposed to face the surface of the polarizing plate (trade name: Dongwoo N-tac, manufacturer: Dongwoo Finechem) and protected by pressing with a laminator. The polarizing plate in which the film lamination agent was laminated | stacked was obtained.

Thereafter, it was confirmed that there was no residue of the adhesive on the surface of the release layer visually.

A sample was prepared in a size of 25 mm x 100 mm from a polarizing plate on which a protective film lamination was laminated, and a tensile tester (Orientic Corporation, trade name "Tensilon") was used, under conditions of a peel rate of 300 mm / min and a peel angle of 180 °. Was measured, and it was 65 mN / 25 mm.

Moreover, after peeling a protective film laminated body from the polarizing plate, it confirmed visually that the adhesive residue does not remain on the surface of a polarizing plate.

The present invention can simplify the structure and manufacturing process of the protective film laminate adhered to the polarizing plate by performing the transfer process, thereby realizing the low cost of the protective film laminate. In addition, when the protective film laminate is adhered to the polarizing plate by carrying out the transfer process, the process is simplified to reduce the manufacturing cost and processing time, there is an effect that waste does not occur.

In addition, since the release layer is positioned on the surface of the polarizing plate in which the protective film laminate of the present invention is laminated, the antifouling property against adhesion of dust or foreign matter is also induced.

Claims (7)

Protective film; An adhesive layer located on one surface of the protective film; And Protective film laminate comprising a release layer located on the other side of the protective film. The method according to claim 1, The protective film has a thickness of 10 ~ 100㎛, protective film, characterized in that selected from the group consisting of polyester, polyethylene, polybutylene, polyacryl, triacetyl cellulose, polycarbonate, polyepoxy, polypropylene and polystyrene Laminate. The method according to claim 1, The thickness of the pressure-sensitive adhesive layer is 3 ~ 50㎛, protective film laminate, characterized in that it comprises an acrylic pressure-sensitive adhesive. The method according to claim 1, The release layer is coated with 0.03 ~ 2g / ㎡, protective film laminate, characterized in that it comprises a curing silicone resin. The method according to claim 1, Protective film laminate, characterized in that further comprising an antistatic layer between the protective film and the release layer or pressure-sensitive adhesive layer. Polarizers; And Located on one surface of the polarizing plate, a polarizing plate laminated with a protective film laminate comprising a protective film laminate comprising a pressure-sensitive adhesive layer, a protective film located on the pressure-sensitive adhesive layer, a release layer located on the protective film. Providing a polarizing plate, Providing a protective film, a pressure-sensitive adhesive layer located on one side of the protective film, a protective film laminate comprising a release layer located on the other side of the protective film, Arranged so that the pressure-sensitive adhesive layer of the polarizing plate and the protective film laminate facing each other, The protective film laminate is a method of manufacturing a polarizing plate laminated on the polarizing plate characterized in that the protective film laminated body by transferring.

Images