KR20130009394A - Optical film laminate roll and method for manufacturina the same - Google Patents

Abstract

PURPOSE: A laminate roll of an optical film is provided to ensure durability at high temperature or under a humid environment. CONSTITUTION: A laminate roll of an optical film comprises a surface protecting film(10), a first adhesive layer(20), the optical film(30), a second adhesive layer(40), and a release film(50). A method for fabricating the laminate roll comprises: a step of sequentially laminating the surface protecting film, the first adhesive layer, the optical film, the second adhesive layer, and the release film; and a step of rolling the laminate of the optical film to be placed outside the surface protection film.

Description

Optical film laminate roll and manufacturing method thereof {OPTICAL FILM LAMINATE ROLL AND METHOD FOR MANUFACTURINA THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical film laminate roll and a method for manufacturing the same, which are excellent in durability even under high temperature or high temperature and high humidity, and which can improve the quality and production yield of liquid crystal display products.

Liquid crystal display devices (LCDs) include a liquid crystal cell and a polarizing plate stacked on both sides of the liquid crystal cell, and in addition, various optical films for improving display quality, such as a retardation plate, a viewing angle expanding film, and a brightness enhancing film. Etc. are provided.

Optical films are defects such as damage caused by various external forces such as bending, crushing or scratches on the surface during handling, transportation, transportation, manufacturing or inspection before being applied to the liquid crystal display, and contamination by foreign matter such as dust. In order to prevent this from happening, the release film and the surface protection film are respectively bonded to both sides, and are used in the form of a laminate. In more detail, as shown in FIG. 1, the surface protective film 10 is bonded to one surface of the optical film 30 via the first adhesive layer 20, and the optical film 30 is formed of the optical film 30. The other surface has a structure in which the release film 50 is bonded through the second adhesive layer 40. After peeling the release film 50 from the optical film laminate and bonding the optical film 30 to a display panel such as a liquid crystal cell through the second adhesive layer 40, the surface protection together with the first adhesive layer 20 is performed. The film 10 is applied to the liquid crystal display device by peeling.

In addition, the optical film laminate is wound and used in the form of a roll rather than a cut sheet in order to minimize defects during the handling process. However, in the roll-shaped optical film laminate, the films are shifted from each other by the stress acting between the constituent members, and bubbles may be mixed or lifted up at this portion. In particular, the optical film laminate is easily exposed to a high temperature or a high temperature and high humidity environment during the handling process, and the above problems are more serious.

The present invention can improve the durability degradation problems such as air bubbles or floating even under high temperature or high temperature and high humidity environment, the optical film laminate roll that can improve the quality and yield of the product when applied to the liquid crystal display device It aims to provide.

Moreover, another object of this invention is to provide the manufacturing method of the said optical film laminated body roll.

1. Laminated in the order of the surface protective film, the first adhesive layer, the optical film, the second adhesive layer and the release film, the peel force A between the surface protective film and the first adhesive layer, the first adhesive layer and the optical A peeling force B between films, a peeling force C between the optical film and the second adhesive layer satisfying the condition of B <A <C, and the optical film laminate roll wound so that the surface protective film is positioned outside.

2. In the above 1, the peel force B between the first adhesive layer and the optical film is 0N / 25mm <B <1N / 25mm, the peel force D between the second adhesive layer and the release film is 0N / 25mm <D ≤ 0.2 N / 25 mm optical film laminate roll.

3. In the above 1, the optical film is a polarizing plate, retardation plate, viewing angle magnification film, brightness enhancement film or color compensation plate optical film laminate roll.

4. In the above 1, wherein the surface protective film and the release film is made of the same material optical film laminate roll.

5. A surface protective film, a first adhesive layer, an optical film, a second adhesive layer and a release film are laminated in this order, the peel force A between the surface protective film and the first adhesive layer, the first adhesive layer and the optical Winding the optical film laminate satisfying the condition that the peeling force B between the films and the peeling force C between the optical film and the second adhesive layer is B <A <C so that the surface protective film is positioned outside. The manufacturing method of an optical film laminated roll.

According to the present invention, even when exposed under high temperature or high temperature and high humidity during the handling process, it is possible to provide an optical film laminate roll having excellent durability without generating bubbles or lifting between components.

In addition, the present invention is wound on the surface protective film constituting the optical film laminate to be located on the outside by a foreign material such as various external forces such as bending, crushing, scratches and the like on the surface during handling process to the release film and display panel The pressure-sensitive adhesive layer on the release film side to be bonded can be prevented from being damaged or contaminated. Through this, product quality and production yield can be improved.

1 is a cross-sectional view of an optical film laminate,
2 is a view for explaining the optical film laminate roll and the winding outer surface thereof of the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical film laminate roll and a method for manufacturing the same, which are excellent in durability even under high temperature or high temperature and high humidity, and which can improve the quality and production yield of liquid crystal display products.

Hereinafter, the present invention will be described in detail.

As shown in FIG. 2, the optical film laminate roll 100 of the present invention has a surface protective film 10, a first adhesive layer 20, an optical film 30, a second adhesive layer 40, and a release agent. A strip-shaped optical film laminate laminated in the order of the film 50 is wound in a roll shape.

In particular, the optical film laminate roll 100 of the present invention has a peel force A between the surface protection film 10 and the first adhesive layer 20, a peel force B between the first adhesive layer 20 and the optical film 30. The peeling force C between the optical film 30 and the second adhesive layer 40 satisfies a condition of B <A <C, and the surface protective film 10 is wound to be positioned outside.

The kind of the optical film 30 is not particularly limited, and may be, for example, a conventional single layer or laminated film such as a polarizing plate, a retardation plate, a viewing angle expanding film, a brightness enhancing film, a color compensating plate, or the like.

The surface protection film 10 is a film for protecting the optical film 30, and the type is not particularly limited as long as it is a known film. For example, polyester-based resins, such as polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate; Cellulose-based resins such as diacetylcellulose and triacetylcellulose; Polycarbonate resin; Acrylic resins such as polymethyl (meth) acrylate and polyethyl (meth) acrylate; Styrene resins such as polystyrene and acrylonitrile-styrene copolymer; Polyolefin resins such as polyethylene, polypropylene, cyclo-based or norbornene-structured polyolefins, ethylene-propylene copolymers; Polyamide resins such as aromatic polyamides; Imide resin; Polyether sulfone type resin; And films composed of thermoplastic resins such as sulfone resins, and the like, and films composed of blends of the above thermoplastic resins may also be used.

The thickness of the surface protection film 10 is not particularly limited, and is usually 500 μm or less, preferably 10 to 200 μm, more preferably 15 to 100 μm in consideration of workability.

The release film 50 is a film for protecting the 2nd adhesive layer 40 for bonding the optical film 30 to a display panel, The kind is not specifically limited. For example, it may be of the same kind and thickness as in the surface protection film 10, and these may be appropriately released by a silicon-based, fluorine-based, silica powder, or the like.

The surface protective film 10 and the release film 50 are bonded to both surfaces of the optical film 30 via the first adhesive layer 20 and the second adhesive layer 40, respectively. The bonding method is not particularly limited as long as it is a known method. For example, the first pressure-sensitive adhesive layer 20 is formed and coated on one surface of the surface protection film 10 by using a conventional coating method to form the first pressure-sensitive adhesive layer 20, and the formed first pressure-sensitive adhesive layer 20 is formed by an optical film ( Join to one side of 30). In addition, the second adhesive layer 40 is formed on one surface of the release film 50 by the same method, and the formed second adhesive layer 40 is bonded to the other surface of the optical film 30.

The first adhesive layer 20 is peeled off together with the surface protection film 10 after bonding the optical film 30 to the display panel, also referred to as a surface protection film pressure-sensitive adhesive layer.

In addition, the second adhesive layer 40 is bonded to the display panel together with the optical film 30 after removing the release film 50, also referred to as a release film pressure-sensitive adhesive layer.

The first and second adhesive layers 20 and 40 may be formed from a pressure-sensitive adhesive composition containing a known pressure-sensitive adhesive resin. For example, as adhesive resin, acrylic resin; Natural rubber-based resins; Styrene resins such as styrene-isoprene-styrene (SIS) block copolymers, styrene-butadiene-styrene (SBS) block copolymers, and styrene-ethylenebutylene-styrene (SEBS) block copolymers; Synthetic rubber resins such as styrene-butadiene rubber, polybutadiene, polyisoprene, polyisobutylene, butyl rubber and chloroprene rubber; Silicone resin etc. are mentioned, Acrylic resin is preferable among these.

In this way, the optical film laminate roll 100 of the present invention is preferably wound so that the surface protection film 10 is located on the outside. The optical film laminate roll is easily damaged due to various external forces such as warpage, crushing, and scratches applied to the surface during handling, transportation, transportation, manufacturing, inspection, etc., in the present invention. Since the surface protection film 10 which is peeled and removed after bonding 30 to the display panel is positioned outside, the effect on the final product may be minimized even if the surface protection film 10 is damaged. In addition, even when the external force is large, even if the first adhesive layer 20 is damaged, since the first adhesive layer 20 is also peeled off together with the surface protection film 10, it is not greatly affected. On the contrary, when the release film 50 is wound to the outside as opposed to the present invention, the release film 50 is easily torn or lifted, and thus the second adhesive layer bonded to the display panel together with the optical film 30 ( 40) is liable to be damaged, which may lower the manufacturing yield and result in a defect of the final product, which is not economical in terms of cost.

The optical film laminate roll 100 of the present invention is characterized in that the peel force magnitude between each film bonded to each pressure-sensitive adhesive layer is configured to satisfy a specific relationship. Specifically, the peel force A between the surface protection film 10 and the first adhesive layer 20, the peel force B between the first adhesive layer 20 and the optical film 30, the optical film 30 and the second adhesive layer The peel force C between 40 satisfies the condition of B <A <C. When this condition is satisfied, the lifting phenomenon and the optical film 30 between the respective component members, in particular, between the surface protection film 10 and the first adhesive layer 20 positioned outside the roll, even in a high temperature or high temperature / humid environment. And the lifting phenomenon between the second adhesive layer 40 can be effectively prevented. In addition, when the optical film 30 is bonded to the display panel, the release film 50 may be easily peeled off, and finally, when the surface protection film 10 is removed, the first adhesive layer 20 may be attached to the optical film 30. It is possible to prevent the appearance defects by being peeled off cleanly without remaining.

While satisfying the above peeling force relationship, it is preferable that the peeling force B between the first adhesive layer 20 and the optical film 30 is 0N / 25mm <B <1N / 25mm. In this case, after applying the optical film laminate roll to the display panel, the surface protection film 10 and the first adhesive layer 20 are finally peeled off stably so that the first adhesive layer 20 does not remain in the optical film 30. can do.

Moreover, it is preferable that peeling force D between the 2nd adhesive layer 40 and the release film 50 is 0N / 25mm <D <0.2N / 25mm. In this case, when the optical film laminate roll is applied to the display panel, the release film 50 may be stably peeled without any damage to the second adhesive layer 40.

The optical film laminate roll of the present invention configured as described above has excellent durability even when exposed to high temperature or high temperature / humid environment during the handling process, and is affected by contamination by foreign matters such as damage by various external forces and dust. By minimizing this, the product quality and production yield can be improved.

The optical film laminate roll of the present invention is laminated in the order of the surface protective film 10, the first adhesive layer 20, the optical film 30, the second adhesive layer 40 and the release film 50, and A strip-shaped optical film laminate that satisfies the same peel force relationship (B <A <C) may be manufactured by a method including winding the surface protective film to be positioned outside.

Hereinafter, preferred examples are provided to aid the understanding of the present invention, but these examples are merely illustrative of the present invention and are not intended to limit the scope of the appended claims. It is apparent to those skilled in the art that various changes and modifications can be made to the present invention, and such modifications and changes belong to the appended claims.

Example

Example 1

4G uncoated disc (SRN231A, Dongwoo Finechem Co., Ltd.) was prepared as an optical film.

Surface protection film (AS-306, Fujimori Co., Ltd.) in which an acrylic pressure-sensitive adhesive layer (thickness 25 µm, first adhesive layer) is formed on one surface of a polyethylene terephthalate (PET) film (38 µm thick) on one surface of the optical film ( PF) was bonded.

Release film (Sp-PLR38T189) in which an acrylic pressure-sensitive adhesive layer (thickness 25 μm, second adhesive layer) is formed on one side of a polyethylene terephthalate (PET) film (38 μm thick) on which the silicone release coating layer is formed on the other side of the optical film And Lintec Corporation (SP) were bonded.

Peeling force A of the joined body was 5 N / 25 mm, peeling force B was 0.2 N / 25 mm, peeling force C was 21 N / 25 mm, and peeling force D was 0.09 N / 25 mm.

The above laminate was wound up so that the surface protective film (AS-306, Fujimori Co., Ltd.) is located outside to prepare an optical film laminate roll.

Example 2-5, Comparative Example 1-3

The same procedure as in Example 1, except that the peel force A, B, C, D was adjusted as shown in Table 1 below.

Comparative Example 4

Example 1 was carried out in the same manner, but the above assembly was wound up to release the release film (Sp-PLR38T189, Lintec Co.) to prepare an optical film laminate roll.

Test Example

The physical properties of the optical film laminate rolls prepared in Examples and Comparative Examples were measured by the following method, and the results are shown in Table 1 below.

1. Peel force (N / 25㎜)

The prepared optical film laminate roll was unwound and cut into a size of 150 mm × 25 mm using a super cutter to prepare a specimen. The peeling force was measured by peeling the surface to be measured from the prepared specimen using a tensile tester (AUTOGRAPH AG-IS 50N, Shimadzu Corporation) at a peel rate of 300 mm / min and a peel angle of 180 °. At this time, it measured similarly with three specimens under the conditions of 23 degreeC and 50% RH, and represented by the average value.

2. Durable

The prepared optical film laminate roll was allowed to stand for 500 hours in an oven at 60 ° C. and 90% RH. Lifting between the constituent members of the rolls left unmarked, in particular, the lifting or peeling phenomenon (E1) between the surface protective film and the first adhesive layer, and the lifting or peeling phenomenon (E2) between the optical film and the second adhesive layer were visually confirmed, and the following criteria were observed. It evaluated based on.

<Evaluation Criteria>

(Circle): There is no lifting and peeling phenomenon.

(Triangle | delta): There exists some floating or peeling phenomenon.

X: There are many lifting or peeling phenomenon.

3. Ease of Peeling

The prepared optical film laminate roll was unwound and cut into a size of 150 mm × 25 mm using a super cutter to prepare a specimen. The release film was peeled from the prepared specimen and bonded to one surface of the glass substrate for liquid crystal cell, and then the surface protective film / first adhesive layer was peeled off. At this time, it is observed whether the second adhesive layer is easily peeled off without remaining on the release film, and after observing whether the first adhesive layer is easily peeled off with the surface protective film without remaining on the optical film based on the following criteria Evaluated.

<Evaluation Criteria>

(Circle): There is no residue of a 1st and 2nd adhesive layer, and peeling of a surface protection film and a release film is easy.

(Triangle | delta): Any one or more of a 1st and 2nd adhesive layer remain | survives, or peeling any one or more of a surface protection film and a release film is not easy.

X: Residual of the 1st and 2nd adhesive layer exists, and peeling any one or more of a surface protection film and a release film is not easy.

4. Product defect

A physical force was applied to the outside of the manufactured optical film laminate roll so that the pressing marks and scratches were generated on the surface. The laminated body was uncoiled, cut into a size of 150 mm × 25 mm using a super cutter to contain pressed marks and scratches, peeled off a release film, bonded to one surface of a glass substrate for a liquid crystal cell, and a surface protective film / first adhesive layer. The specimen was peeled off. The defect of the produced test piece was visually observed and evaluated based on the following criteria.

<Evaluation Criteria>

(Circle): There is no appearance defect and a bonding defect.

X: Appearance defect or joining defect exists.

division Of roll
Outside Peeling force (N / 25mm) durability Peelability Bad B <A <C A B C D E1 E2 Example 1 PF satisfied 5 0.2 21 0.09 ○ ○ ○ ○ Example 2 PF satisfied 7 0.1 17 0.13 ○ ○ ○ ○ Example 3 PF satisfied One 0.2 21 0.1 ○ ○ ○ ○ Example 4 PF satisfied 5 0.2 21 0.25 ○ ○ △ ○ Example 5 PF satisfied 5 2.5 21 0.09 ○ ○ △ ○ Comparative Example 1 PF dissatisfaction 8 0.2 0.9 3 △ × × ○ Comparative Example 2 PF dissatisfaction 0.97 3 0.6 2 × × × ○ Comparative Example 3 PF dissatisfaction 0.5 0.97 3 0.13 × ○ × ○ Comparative Example 4 SP satisfied 5 0.2 21 0.09 ○ ○ ○ ×

As shown in Table 1, according to the present invention, the surface protective film, the first adhesive layer, the optical film, the second adhesive layer and the release film are laminated in the order of the peel force conditions between the components (B <A <C) It was found that the optical film laminate rolls of Examples 1 to 5 wound up to satisfy the surface protection film and positioned on the outside were superior in durability to Comparative Examples 1 to 4. In particular, when the value of the peeling force D and the peeling force B satisfies the specific range while satisfying the above conditions, the effect was not only better but also the peelability was better. In addition, although the peeling force condition was satisfied, Comparative Example 4 wound up so that the release film was on the outside, a defect occurred due to the influence of the external force.

10: surface protection film 20: first adhesive layer
30: optical film 40: second adhesive layer
50: release film
100: optical film laminate

Claims (5)

It is laminated in the order of the surface protective film, the first adhesive layer, the optical film, the second adhesive layer and the release film,
The peel force A between the surface protection film and the first adhesive layer, the peel force B between the first adhesive layer and the optical film, and the peel force C between the optical film and the second adhesive layer are B <A <C. Satisfying,
An optical film laminate roll wound so that the surface protection film is located outside.
The method according to claim 1, wherein the peel force B between the first adhesive layer and the optical film is 0N / 25mm <B <1N / 25mm, the peel force D between the second adhesive layer and the release film is 0N / 25mm <D ≤ 0.2 N / 25 mm optical film laminated roll.
The optical film laminate roll according to claim 1, wherein the optical film is a polarizing plate, a retardation plate, a viewing angle expanding film, a brightness enhancing film, or a color compensating plate.
The optical film laminate roll of claim 1, wherein the surface protection film and the release film are made of the same material.
A surface protective film, a first adhesive layer, an optical film, a second adhesive layer and a release film are laminated in this order, the peel force A between the surface protection film and the first adhesive layer, between the first adhesive layer and the optical film Roll form including the step of winding the surface protective film to the outside of the optical film laminate satisfying the condition that the peel force B, the peel force C between the optical film and the second adhesive layer is B <A <C. The manufacturing method of the optical film laminated body of this.

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