KR20070096845A - Method for packing optical film-superposed body - Google Patents

Abstract

An optical film laminate packing method is provided to prevent damage of an adhesive layer caused by attaching the adhesive layer on a packing film or an adhesive agent from being stuck to the surface of an optical film. A method for packing an optical film laminate(10) with a packing film by laminating plural optical films comprises the steps of: inserting the optical film laminate having protection sheets arranged at the upper and lower sides, into a gap between two upper and lower packing films; making a film package(16) by sealing the peripheral part of the optical film laminate by heating and cutting the optical film laminate at the same time; and thermally shrinking the surface packing film by heating the film package.

Description

Packing method of optical film stack {METHOD FOR PACKING OPTICAL FILM-SUPERPOSED BODY}

1 is a schematic diagram of an optical film having an adhesive layer.

It is a schematic diagram of an optical film superimposition body and a packaging film.

3 is a schematic diagram of one embodiment of the apparatus used in the present invention, (A) is a front schematic diagram, and (B) is a plan schematic diagram.

<Explanation of symbols for main parts of the drawings>

1: optical film 2: adhesive layer

3: protective film 4: release film

5: optical film with adhesive layer 6: optical film superposition

7: packaging film 10: optical film stack

11: packing film 13: conveyor

14: heat sealer 15: hot stove

16: Package of Optical Film Overlay

[Patent Document 1] Japanese Unexamined Patent Publication No. 10-175664

[Patent Document 2] Japanese Unexamined Patent Publication No. 2000-191994

<Technology field>

The present invention relates to a package and a packaging method of an optical film stack. In detail, it is simpler and does not cause mold collapse, and furthermore, the optical film overlapping does not cause foreign matters such as dust, mixed with the adhesive layer to the packaging film, resulting in the loss of the adhesive layer, or the adhesion of the adhesive to the surface of the optical film. It relates to the packing method of the sieve.

<Background technology>

Optical films, such as a polarizing film, a polarizing separation film, and retardation film, or the optical film which laminated | stacked these multiple sheets are useful as one of the optical components which comprise a liquid crystal display device, and are rectangular optical which is a shape matched with the screen of a liquid crystal display device. It is used as a film.

With respect to such an optical film 1, in order to simplify the attachment process to a liquid crystal display device, the adhesive layer 2 is often provided in one or both surfaces, and on the surface where the adhesive layer is not provided, the optical film surface The protective film 3 is often provided for the purpose of protecting this. Moreover, on the adhesive layer 2, the peeling film 4 is adhered in order to prevent foreign substances, such as dust, from sticking, or adhere | attaching optical films, and ships as the optical film 5 which has an adhesive layer (FIG. 1). In addition, the peeling film is removed and discarded immediately before adhering to a liquid crystal display device.

With respect to the optical film 5 having such an adhesive layer, a plurality of sheets thereof are superimposed to form an optical film superposed body 6, and the entirety thereof is surrounded by a packaging film 7 to form a package of an optical film superposed body, which is a container. It is often packed inside and shipped out (FIG. 2). As the packaging film 7, ordinary packaging films such as polyolefin films such as polyethylene films and polypropylene films, polyester films, and polyamide films are used. In addition, it is known to use a film subjected to an antistatic treatment to prevent the incorporation of foreign substances such as dust, and a film surface-treated with a release agent to prevent the adhesive from adhering to the packaging film and the adhesive at the end of the optical film. See Patent Document 1).

In a package in which an optical film layered product is packaged with these packaging films, the optical film layered body collapses during transportation, and optical films having an adhesive layer, and optical films and packaging films having the adhesive layer are rubbed to cause peeling of the release film. Furthermore, the adhesive may contact with a packaging film in some cases.

In order to prevent this, the method of fastening an optical film superimposition body tightly with a belt-shaped ring, and then packing this with a packaging film is known (refer patent document 2).

However, this method has a problem that it takes time, and is simpler, does not cause mold collapse of the optical film superimposed body, and furthermore, foreign matters such as dust are mixed or the adhesive layer adheres to the packaging film, resulting in a loss of the adhesive layer, There has been a need for a package of optical film overlays that does not cause the problem of adhesives adhering to the optical film surface.

<Start of invention>

The object of the present invention is simpler, and does not cause mold collapse of the optical film superimposed body, and furthermore, foreign substances such as dust are mixed, the adhesive layer adheres to the packaging film, and the adhesive layer is missing, or the adhesive is attached to the optical film surface. It is to provide a method for packaging an optical film stack which does not cause a problem.

Means for Solving the Invention

This invention is a method of packaging the optical film superimposition body which overlaps multiple sheets of optical films with a packaging film, The process of inserting the optical film superimposition body in which the protective sheet was arrange | positioned up and down between two upper and lower packaging films, and this optical film It is a packaging method of an optical film overlapping body, which has the process of heat-sealing and surrounding the superimposed body, and melt | dissolution to make a film package body, and the process of heating the said film package body and heat shrinking the packaging film of a surface.

From the edge part of an optical film layered product, the gap of 10-25% of the length of an optical film layered body is made to heat-sealed, and it is the packaging method of the said optical film layered product characterized by the above-mentioned.

It is the packaging method of the said optical film laminated body characterized by heating the hot air of 90-120 degreeC for 10 to 30 second from 0.5 to 2 Nm <^3> / cm <^2> / hr from the upper and lower sides of an optical film laminated body.

An optical film is a package of the said optical film superimposition which is 1 or more types of films chosen from the group which consists of a polarizing film, a polarization separating film, and retardation film.

Moreover, the optical film is a package of the said optical film superimposition which is a laminated body of 2 or more types of films selected from the group which consists of a polarizing film, a polarization separating film, and retardation film.

Moreover, it is a package of the optical film superimposition obtained by the method in any one of said.

Best Mode for Carrying Out the Invention

As an optical film applied to this invention, a polarizing film, a polarization separating film, a retardation film, etc. are mentioned, for example. Moreover, these laminated bodies may be sufficient. In order to simplify the attachment process to a liquid crystal display device, the optical film 1 is provided with the contact bonding layer 2 on the single side | surface or both surfaces. On the other hand, the protective film 3 is provided in the surface in which the adhesive layer is not provided in order to protect the optical film surface. Moreover, on the adhesive layer 2, the peeling film 4 is stuck in order to prevent foreign substances, such as dust, from sticking together, or to adhere | attach rectangular optical films, These laminated bodies are handled as the optical film 5 which has an adhesive layer. (FIG. 1). In addition, the peeling film is removed and discarded immediately before adhering to a liquid crystal display device.

As a polarizing film, what laminated | stacked both surfaces of the polarizer film which consists of polyvinyl alcohol (PVA) dyed with iodine or a dichroic dye normally by the film made from a triacetyl cellulose (TAC) etc. is used. The thickness of a polarizer film is about 15-30 micrometers normally, and the thickness of a TAC film is about 40-200 micrometers normally. The polarizer film and the TAC film are usually bonded with a polyvinyl alcohol adhesive or the like.

As a retardation film, the uniaxial oriented film obtained by extending | stretching a polycarbonate-type resin film, etc. are used, for example, The thickness is about 30-100 micrometers normally.

Moreover, the film which has directivity, such as a light control film etc. which has the property which the incident light from a specific angle scatters and the incident light from other angles transmits as it is, is mentioned. As such a light control film, "Lumisti (registered trademark)" by Sumitomo Chemical Co., Ltd. is illustrated.

In addition, the optical film may be a laminated film of a light control film, a polarizing plate, and a retardation plate. The shape of such an optical film is often processed into the rectangle of the magnitude | size corresponding to the screen size of the target liquid crystal display device.

A polarizing film is a film which has a function which permeate | transmits the light parallel to a transmission axis direction, and absorbs light parallel to the absorption axis direction orthogonal to a transmission axis, and is also called an absorption type polarizing film. Usually, this includes a polarizer and a protective film laminated on both sides thereof, and the polarizer is a film obtained by uniaxial stretching, dyeing with a dichroic dye, and boric acid treatment on a polyvinyl alcohol film having a film thickness of 10 µm to 150 µm. As a protective film, the cellulose acetate resin film, for example, a triacetyl cellulose film is used normally. For example, "Sumikaran (registered trademark) SRW862A" (Sumitomo Chemical Co., Ltd. product) is mentioned.

The polarization splitting film is a film having a function of transmitting light parallel to the transmission axis direction and reflecting light parallel to the reflection axis direction orthogonal to the transmission axis, and is called a reflective polarizing film or a non-absorbing polarizing film. It is also called a brightness rising film because the reflected light is reused and the brightness is improved. Polyesters, particularly copolymers containing polyethylene naphthalate and polyethylene naphthalate units as a main component, have excellent performance as raw materials, and are commercially available, for example, under the trade name "DBEF" (manufactured by Sumitomo 3M Co., Ltd.).

Retardation film is a film provided with retardation (retardation) by extending | stretching a resin film, For example, polycarbonate resin, polysulfone resin, polyether sulfone resin, polyarylate resin, cycloolefin type Resin, norbornene-type resin, etc. are mainly used. A well-known method can be employ | adopted for extending | stretching, and longitudinal stretching like roll-to-roll stretching, and horizontal stretching like tenter stretching are used a lot. Moreover, although extending | stretching direction may be uniaxial stretching, the orientation of the thickness direction may be performed for adjustment of the viewing angle at the time of using for a liquid crystal display device. Although the retardation value of a retardation film is suitably determined according to a desired characteristic, in general, the thing of the range of 100-1,000 nm is used a lot. Also, a quarter wave film or a half wave film is one of the preferred forms. For example, "Sumikaraite (registered trademark) SEF440138" (manufactured by Sumitomo Chemical Co., Ltd.), which is a uniaxially stretched retardation film having a thickness of 40 µm, is made of polycarbonate.

The adhesive agent constituting the adhesive layer 2 is not particularly limited as long as it is transparent and optically isotropic, and usually a pressure-sensitive adhesive (adhesive) is used. As the pressure sensitive adhesive, an acrylic pressure sensitive adhesive, a urethane pressure sensitive adhesive, or the like is used. The thickness of the adhesive layer is about 10 μm to 50 μm.

As a peeling film, a polyethylene film, a polyethylene terephthalate (PET) film, etc. are used normally, and the thickness is 20-40 micrometers normally. Such release film may be imparted with releasability by, for example, treating the surface thereof with a silane coupling agent or the like.

By overlapping a plurality of sheets of the optical film 5, the optical film superposed body 6 is formed (FIG. 2). Although the number of sheets in which the optical film superimposition body 6 overlaps is not specifically limited, In order that the handling of the superimposition body 6 obtained will not become difficult, it selects suitably in consideration of size, a weight, etc., for example, 20-500 sheets It is enough. The optical film 5 is superimposed so that the height may be about 5 to 200 mm normally. The optical film overlayer 6 is wrapped with the packaging film 7, the surroundings are heat sealed, and it is set as a film package, and the surface packaging film is heat-shrinked and it is set as the package of an optical film overlayer.

Examples of the packaging film 7 include a film or a bag containing polyolefins such as polyethylene (PE) and polypropylene (PP), including linear low density polyethylene (LLDPE), and may be a single layer film or a multilayer. It may be a film. If the packaging film 7 is transparent, the inside can be easily observed.

As the packaging film, it is preferable to use an antistatic treatment or a thing containing an antistatic agent in order to prevent the incorporation of foreign substances such as dust.

As the antistatic treatment method, a known method is adopted. For example, the method of coating an antistatic agent on a packaging film, etc. are illustrated. In the case of coating, one side or both sides of the packaging film may be coated. If only one side of the coating film exhibits effective dust prevention ability, it is economically advantageous to coat the one side. It is preferable to employ.

As a method of containing an antistatic agent in a packaging film, the method of kneading an antistatic agent in the base material of a packaging film, and shape | molding to a packaging film etc. are illustrated, for example.

As an antistatic agent, anionic surfactant (for example, alkylbenzenesulfonate, higher alcohol sulfate ester etc.), nonionic surfactant (for example, fatty acid ester of polyhydric alcohol, ethylene oxide addition product of alkylamine, and Fatty acid esters of ethylene oxide adducts of alkylamines, ethylene oxide adducts of alkylamides, etc.), cationic surfactants (eg, aliphatic amine salts, quaternary ammonium salts, etc.), amphoteric surfactants (eg, Imidazoline type, betaine type, etc.) can be used. Among them, fatty acid esters of polyhydric alcohols, ethylene oxide adducts of alkylamines, fatty acid esters of ethylene oxide adducts of alkylamines, ethylene oxide adducts of alkylamides, betaine type amphoteric surfactants, and the like are preferable.

As the packaging film, in order to prevent the adhesive layer from adhering to the packaging film and causing the adhesive layer to be defective, it is preferable to use a release treatment on the inner side of the packaging film (the side in contact with the optical film stack).

The well-known method is employ | adopted as the method of a mold release process. For example, the method of coating suitable mold release agents, such as silicone type, such as dimethyl polysiloxane, and fluorine type and long chain alkyl type, is illustrated. As the coating method, conventionally known methods such as a bar coating method, a doctor blade method, a reverse roll coating method, a gravure roll coating method and a spin coating method can be used. As these mold release agents, it can fix to a base material by thermosetting, ultraviolet curing, electron beam hardening, etc.

Moreover, also when using the film containing an anti blocking agent as a packaging film, an adhesive layer can be prevented from adhering to a packaging film and an adhesive layer being missing.

As an anti blocking agent, a well-known thing can be employ | adopted without a restriction. The particle size of the anti-blocking agent is preferably about 0.1 to 50 μm, and the material is aluminum silicate, diatomaceous earth, thermally produced silicon dioxide, colloidal silica gel, micro silica, hard stone, kaolin, talc, cement, calcium carbonate and And crosslinked polymer beads mainly composed of inorganic particles such as magnesium hydrosilicate, acrylic monomers and / or styrene monomers.

As a method of dispersing the anti blocking agent in the resin, a known method can be employed without limitation.

For example, the anti-blocking agent can be dispersed in the resin by kneading while applying shear at room temperature or by heating using kneading means such as a mill, kneader, mortar, attritor, roller, or extruder. Moreover, after dissolving resin in a solvent and disperse | distributing particle | grains in this solution, the method of removing a solvent is also employable. The resin composition in which this anti blocking agent is disperse | distributed is shape | molded normally with the film of about 5-200 micrometers in thickness. In molding, various known methods can be employed without limitation. For example, it can shape | mold by press molding, extending | stretching, roller rolling, inflation molding, etc. at room temperature or under heating. Moreover, after melt | dissolving the resin composition which the anti blocking agent disperse | distributed in a solvent and being flexible to a support body, the method of removing a solvent can also be employ | adopted.

As a film containing an anti blocking agent, the stretched polyolefin resin film containing the crosslinked polymer bead of Unexamined-Japanese-Patent No. 8-225655 can be used preferably.

Although the thickness of a packaging film differs also according to the kind of film used, it is about 0.01-0.1 mm, Preferably it is about 0.01-0.03 mm in view of the strength, heat sealing property, and heat shrinkability for protecting an optical film superimposition body. Film is used.

When the slipperiness | lubricacy of an optical film superimposition body and a packaging film is poor, breakage of an edge part, the wrinkle from an edge part, and the curvature of an optical film may arise. The rate which occurs especially in a large film is high. In order to prevent this, it is preferable to arrange a protective sheet of the same size as the optical film stack on the top and bottom surfaces of the optical film stack.

Although it will not restrict | limit especially if it is higher rigidity than an optical film superposition body as a protective sheet, The sheet made from polystyrene is used preferably. In order to improve the slip property, a sheet having a fine checkered pattern on the surface is preferably used. In addition, those having a thickness of the protective sheet of about 0.5 to 5 mm are used.

3 is a schematic diagram of an embodiment of the apparatus used in the present invention, (A) is a front schematic diagram, and (B) is a plan schematic diagram.

The packaging film 12 arranged up and down is conveyed by the conveyor 13 via a roller. The optical film overlapping body 10 in which the protective sheet (not shown) is arrange | positioned at the upper surface and the lower surface is conveyed by a conveyor, and is inserted between packaging films. In Fig. 3, a half-folded film is used, and the folded portion of the half-folded film is located on (A) the back side of the drawing, (B) the plane side of the drawing, (A) the front side of the drawing, and (B) the bottom of the drawing. The side is open. From this perforated part, the optical film superimposition body 10 in which the protective sheet was arrange | positioned is conveyed and inserted.

In FIG. 3, although the optical film superimposition is inserted from the perpendicular | vertical direction with respect to the conveyance direction of a packaging film, it is made to insert an optical film superimposition from the conveyance direction of a packaging film by changing the conveyance direction of a packaging film in the middle. It is also possible.

Subsequently, the heat sealer 14 melts and heat seals around the optical film stack. In the example of FIG. 3, one side end part of a perpendicular | vertical direction and a conveyance direction with respect to a conveyance direction is sealed, and it melts simultaneously. The film package body by which the back and front of a conveyance direction, and one side end part was sealed is obtained.

At this time, about 10 to 25% of the length of the optical film overlapping body, and preferably about 15 to 20% of length space | interval are sealed from the edge part of an optical film overlapping body. For example, for an optical film of 20 inches, about 7 mm in the longitudinal direction, about 4 mm in the width direction, for an optical film of 32 inches, about 11 mm in the longitudinal direction, about 6 mm, 40 inches in the width direction In the case of the optical film of about 18 mm in the longitudinal direction, about 10 mm in the width direction to empty the gap.

If the gap is smaller than about 10% of the length of the optical film stack, thermal damage may occur to the optical film stack during heat sealing, and when the heat shrink is caused, the optical film stack may be bent due to shrinkage force. Not. Moreover, when the space | interval becomes larger than about 25%, even if it heat-shrinks, an optical film will be twisted between the packaging film and an optical film superimposition, and it is unpreferable.

When conveying the optical film laminated body, such as when conveying the package of the optical film laminated body obtained by heat-sealing, when conveying the inserted optical film laminated body when inserting an optical film laminated body between packaging films, The speed is about 4 m / min or less. It is not preferable to exceed about 4 m / min because the laminated optical film is distorted.

Subsequently, the obtained film package is put in the hot stove 15, and the packaging film is heat shrinked. Hot air of about 90 to 120 캜, preferably about 95 to 110 캜 is shot from above and below the package. If it is lower than about 90 degreeC, it also depends on the packaging film to be used, but when it exceeds about 120 degreeC without heat shrinking, heat damage may be caused to an optical film, and it is unpreferable. In addition, when hot air is shot from the package body side, when the packaging film is broken or heat sealing is insufficient, hot air is directly directed to the optical film, causing heat damage, which is not preferable.

The amount of hot air is expressed as the air volume per unit area of the optical film superimposed body, and is about 0.5 to 2 Nm ³ / cm ² × hr, preferably about 1 to 1.5 Nm ³ / cm ² × hr, and the hot air is about 10 to 30 seconds, Preferably, the heat shrinkage is performed by shooting for about 15 to 20 seconds.

The package 16 of the optical film superposition body thus obtained has almost no gap between the optical film superposition body and the packaging film, does not cause mold collapse of the optical film superposition body, and furthermore, foreign substances such as dust are mixed or the adhesive layer It does not cause the problem that adhesive layer adheres to this packaging film, and an adhesive layer is missing or an adhesive adheres to the surface of an optical film.

The package of the optical film superimposition body obtained by the method of this invention is normally put in the outer bag of the waterproof film which laminated aluminum foil etc., and put into a container, and is transported further. It does not cause mold collapse of the optical film superimposition during transportation, and thus the adhesive layer adheres to the packaging film so that the adhesive layer is missing or the adhesive is adhered to the optical film surface. In addition, foreign matters such as dust do not mix.

<Example>

Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to this Example.

<Example 1>

Using the same packaging apparatus as shown in FIG. 3, the optical film superposed body was packaged.

(1) Optical film superposition body: The polarizing film SRF862APG6-S / 81 (made by Sumitomo Chemical Co., Ltd.) was cut | disconnected to 400 mm in length x 300 mm in width, and the thing which overlapped 20 pieces was prepared.

(2) Packaging film: Polyethylene shrink film (made by Okura Kogyo Co., Ltd.), thickness 15 micrometers, half folded width 500 mm.

(3) Protection sheet: 400mm in length X 300mm in width X thickness 1mm, checkered surface.

(4) Packing machine: L type packing machine (manufactured by Nissan Kiriko)

The optical film superimposition body was inserted between the half-folded packaging films, the space | interval of about 7 mm was respectively provided in the longitudinal direction and about 4 mm in the width direction, respectively, and the packaging film was heat-sealed and the film package body was obtained.

Inserts it into a hot-air and hot air was of about 100 ℃ to about 1 Nm ³ / cm ² × hr heat shrinking the packaging film ssoyeo to about 18 seconds, the film package from above and below.

In the package of the obtained optical film layered product, there was almost no space | interval between an optical film layered product and a packaging film, and the curvature of the optical film was also not seen.

The package of this optical film superposition body was put into the outer bag containing the waterproof film in which aluminum foil was laminated, and it put in the cardboard box, and packaged it further. At this time, the cushioning material was inserted in the clearance gap of the cardboard box.

The drop test which drops the cardboard box containing the package of this optical film superimposition at 1 m in height was repeated 50 times. After the test, the appearance and contents of the package body were confirmed. As a result, the appearance of the package was good, and the package form before the drop test was maintained. In addition, there was no adhesion of foreign matter or the optical film adhesive layer, and no particular problem was observed in the optical film.

The optical film manufacturing method according to the present invention is simpler, and according to this, it does not cause the collapse of the optical film superimposed body, and furthermore, foreign matters such as dust are mixed, or the adhesive layer adheres to the packaging film, resulting in the loss of the adhesive layer, or the optical film surface. It does not cause the problem that the adhesive is attached to the.

Claims (6)

A step of inserting an optical film overlapping body in which a protective sheet is disposed up and down between the upper and lower packaging films, a step of heating and sealing the periphery of the optical film overlapping body to melt and forming a film package, and the film packaging body A method of packaging an optical film layered product formed by stacking a plurality of optical films, the packaging film comprising: a step of heating the film to heat shrink the surface packaging film. The packaging method of the optical film overlapping body according to claim 1, wherein a gap of 10 to 25% of the length of the optical film stacking body is emptied from the end of the optical film stacking body to be heat sealed. The optical film superimposition according to claim 1 or 2, wherein hot air at 90 to 120 ° C. is heated by shooting at 0.5 to 2 Nm ³ / cm ² × hr for 10 to 30 seconds from above and below the optical film overlapping body. Packing method of sieve. The packaging method of an optical film superimposed body according to any one of claims 1 to 3, wherein the optical film is at least one film selected from the group consisting of a polarizing film, a polarization separating film, and a retardation film. The method for packaging an optical film superimposed product according to any one of claims 1 to 3, wherein the optical film is a laminate of two or more films selected from the group consisting of a polarizing film, a polarization separating film, and a retardation film. The package of the optical film superimposition body obtained by the method in any one of Claims 1-5.

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