TW201736110A - Method for manufacturing laminated optical film - Google Patents

Abstract

The present invention provides a method for producing a laminated optical film which is capable of preventing contamination of an adhesive roller by an adhesive or an adhesive for bonding the optical films to each other. The present invention relates to a method of manufacturing a laminated optical film in which a first optical film 2, an adhesive layer 5, and a second optical film 3 are introduced between a pair of bonding rollers 7a and 7b under rotation, and the laminated optical film is bonded to each other. In the case where the width WA of the adhesive layer 5 is equal to or larger than the width W1 of the first optical film 2, the position of the first optical film 2 in the width direction is within the width WA of the adhesive layer 5, and the width W2 of the second optical film 3 is More than the width WA of the adhesive layer 5, the second optical film 3 is located at the existence width WA of the adhesive layer 5, and is bonded between the bonding roller 7a on the first optical film 2 side and the first optical film 2 The third optical film 6 having a width larger than the width WA of the adhesive layer 5 is inserted into the width WA of the agent layer 5.

Description

Method for manufacturing laminated optical film

The present invention relates to a method of producing a laminated optical film.

Conventionally, a method of producing a laminated optical film that is pressed by a pair of bonding rolls by passing a plurality of optical films through an adhesive layer or an adhesive layer has been known (for example, see Patent Document 1). The layer of the adhesive or adhesive layer is typically supplied by applying an adhesive or adhesive to either of the laminated optical films.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2014-172290

At the time of bonding, if an adhesive or an adhesive overflows from the edge of the width direction of the optical film, the adhesive or the adhesive adheres to the adhesive roller to be contaminated. Further, the adhesive or the adhesive adhering to the bonding roller is transferred to the subsequent optical film, and becomes a cause of pressure sticking when the laminated optical film is wound into a roll.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a laminated optical film which is capable of preventing contamination of an adhesive roller by an adhesive or an adhesive for bonding the optical films to each other.

The present invention relates to a method for producing a laminated optical film, in which a first optical film, an adhesive layer, an adhesive layer, and a second optical film are bonded to each other in a sequence between a pair of bonding rolls that are rotating. When the first optical film is bonded to the second optical film, the width of the adhesive layer or the adhesive layer is greater than or equal to the width of the first optical film, and the width of the first optical film is introduced. The position in the width direction is within the width of the adhesive layer or the adhesive layer, the width of the second optical film is greater than the width of the adhesive layer or the adhesive layer, and the second optical film is located on the adhesive layer or adhesive. The presence width of the agent layer is interposed between the bonding roller on the first optical film side and the first optical film, and has a width larger than the thickness of the adhesive layer or the adhesive layer. The third optical film.

When the first optical film and the second optical film are bonded by this manufacturing method, a second optical film wider than the adhesive layer or the adhesive layer is interposed between the adhesive layer or the adhesive layer and the adhesive roller. Or the third optical film prevents contamination of the bonding roller by the adhesive layer or the adhesive layer.

In the manufacturing method, the width of the bonding roller on the first optical film side is smaller than the width of the third optical film, and the position of the bonding roller on the first optical film side in the width direction is within the width of the third optical film. The form. At this time, the adhesive roller can be further prevented from being caused by an adhesive or an adhesive. Pollution.

According to another aspect of the present invention, there is provided a method for producing a laminated optical film, wherein a first optical film, an adhesive layer or an adhesive layer, and a second optical film are provided between a pair of bonding rolls that are rotating This order is introduced in a state of being aligned in a direction connecting the pair of bonding rolls, and the first optical film is bonded to the second optical film. When the bonding is performed, the width of the adhesive layer or the adhesive layer is greater than or equal to the width of the first optical film. The width of the first optical film in the width direction is within the width of the adhesive layer or the adhesive layer, and the width of the second optical film is larger than the width of the adhesive layer or the adhesive layer, and the second optical film is located. The presence of the adhesive layer or the adhesive layer is such that the position of the adhesive roller in the width direction on the first optical film side is within the width of the first optical film.

According to this manufacturing method, although the adhesive layer or the adhesive layer overflows from the width of the first optical film, the width of the bonding roller on the first optical film side is smaller than the width of the first optical film, and the first The position of the adhesive roller in the width direction on the optical film side is within the width of the first optical film side, so that the adhesive roller can be prevented from being contaminated by the adhesive layer or the adhesive layer.

Meanwhile, another aspect of the present invention provides a method for producing a laminated optical film, wherein a first optical film, an adhesive layer or an adhesive layer, and a second optical are interposed between a pair of bonding rolls that are rotating The film is introduced in this order in a direction in which the pair of bonding rolls are connected, and the first optical film is bonded to the second optical film. When the film is bonded, the width of the adhesive layer or the adhesive layer is less than the first optical. Film width, adhesive layer or adhesive The position in the width direction of the layer is within the width of the first optical film, the width of the second optical film is greater than the width of the adhesive layer or the adhesive layer, and the second optical film is located in the adhesive layer or the adhesive layer. There is a width.

According to this manufacturing method, since the possibility that the adhesive layer or the adhesive layer overflows the width of the first optical film and the second optical film is extremely small, it is possible to prevent the adhesive roller from being contaminated by the adhesive or the adhesive.

In this manufacturing method, the width of the bonding roller on the first optical film side is smaller than the width of the first optical film, and the bonding roller on the first optical film side can be formed in the width direction in the width of the first optical film. The form inside. At this time, the adhesive roller can be prevented from being contaminated by the adhesive or the adhesive.

Meanwhile, in the manufacturing method, the width of the adhesive layer or the adhesive layer can be made smaller than the width of the first optical film by 0.1 to 50 mm. At this time, the first optical film and the second optical film can be sufficiently adhered or bonded to the edge in the width direction.

In each of the above-described production methods, the first optical film has a resin substrate and an optical functional layer provided on one surface or both surfaces of the resin substrate, and the resin substrate and the optical functional layer are aligned at equal widths to each other. The first optical film is disposed such that the optical function layer side faces the adhesive layer or the adhesive layer side, and the second optical film can be formed into a protective film. In this embodiment, the first optical film has a resin substrate and an optical function layer, but the edge film thickness in the width direction is stable.

The optical functional layer may be a polarizer, and in this case, the polarizer may be in the form of being applied to a resin substrate.

In another aspect of the present invention, a laminated optical is provided a method for producing a layer, wherein a resin substrate and an optical functional layer, an adhesive layer or an adhesive layer and a protective film provided on one or both sides of the resin substrate are interposed between a pair of bonding rolls in rotation The order is introduced in a state of being aligned in a direction connecting the pair of bonding rolls, and the optical function layer is bonded to the protective film. When bonding, the width of the optical function layer is smaller than the width of the resin substrate, and the adhesive layer or the adhesive layer The width is greater than the width of the optical functional layer and less than the width of the resin substrate, and the resin substrate is located at the presence width of the inner optical functional layer and the adhesive layer or the adhesive layer, and the width of the protective film is greater than the adhesive layer or The width of the adhesive layer, the protective film is located in the presence of the inner adhesive layer or the adhesive layer.

When the optical functional layer is bonded to the protective film by this manufacturing method, a resin substrate or a protective film wider than the adhesive layer or the adhesive layer is interposed between the adhesive layer or the adhesive layer and the adhesive roller. Therefore, the adhesive roller can be prevented from being contaminated by the adhesive or the adhesive.

In the production method, the width of the bonding roller on the resin substrate side is smaller than the width of the resin substrate, and the bonding roller on the resin substrate side can be formed in the width direction in the width of the resin substrate. At this time, it is possible to further prevent the bonding roller from being contaminated by the adhesive or the adhesive.

Meanwhile, in the manufacturing method, the optical functional layer may be a polarizer, and in this case, the polarizer may be in the form of a coating on a resin substrate.

According to the present invention, a system for laminating optical films can be provided The method of manufacturing is to prevent the adhesive roller from being contaminated by an adhesive or an adhesive for bonding the optical films to each other.

1A to 1D‧‧‧ laminated optical film

2‧‧‧1st optical film

3‧‧‧Protective film (2nd optical film)

4A to 4D‧‧‧ laminated body

5‧‧‧ adhesive layer

6‧‧‧ Temporary protective film (3rd optical film)

7a‧‧‧1st optical film side adhesive roller

7b‧‧‧Adhesive roll on the protective film side

10‧‧‧Polar plate

21‧‧‧Resin substrate

22‧‧‧ polarizer

W ₁ ‧‧‧The width of the first optical film

W ₁₁ ‧‧‧Width of resin substrate

W ₁₂ ‧‧‧Polar width

W ₂ ‧‧‧Width of protective film

W ₃ ‧‧‧ Temporary protective film width

W _A ‧‧‧The width of the adhesive layer

W _R1 ‧‧‧The width of the bonding roller on the 1st optical film side

W _R2 ‧‧‧Width of the adhesive roller on the protective film side

Fig. 1 is a cross-sectional view showing a laminated optical film produced by the production method of the first embodiment.

Fig. 2 is a view showing a manufacturing method of the first embodiment.

Fig. 3 is a sectional view taken along line III-III of Fig. 2, showing a state of lamination at the time of bonding in the first embodiment.

Fig. 4 is a cross-sectional view showing a laminated optical film produced by the production method of the second embodiment.

Fig. 5 is a view showing a manufacturing method of the second embodiment.

Fig. 6 is a sectional view taken along line VI-VI of Fig. 5, showing a state of lamination at the time of bonding in the second embodiment.

Fig. 7 is a cross-sectional view showing a laminated optical film produced by the production method of the third embodiment.

Fig. 8 is a view showing a state of lamination at the time of bonding in the third embodiment.

Fig. 9 is a cross-sectional view showing a laminated optical film produced by the production method of the fourth embodiment.

Fig. 10 is a view showing a state of lamination at the time of bonding in the fourth embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. Also, attach the same or equivalent parts of each figure The same symbols are given, and overlapping descriptions are omitted. At the same time, the dimensional ratio of each surface is not necessarily consistent with the actual one, and in particular, the thickness or width of the film is relatively exaggerated.

<First embodiment>

(layered optical film)

As shown in Fig. 1, the laminated optical film 1A produced by the method for producing a laminated optical film of the first embodiment is formed by passing the adhesive layer 5 on one surface of the first optical film 2 to laminate the second optical film 3. The third optical film 6 is laminated on the other surface of the first optical film 2. The first optical film 2 has two layers, that is, a resin substrate 21 and a polarizing plate 22 provided on one surface thereof, and these layers can be peeled off from each other.

In the first optical film 2, the resin substrate 21 and the polarizer 22 are aligned at equal widths to each other, and the first optical film 2 is disposed such that the polarizer 22 side faces the adhesive layer 5 side. In addition, the "width" of each optical film in this specification means the direction perpendicular to the conveyance direction of each optical film at the time of manufacture of the laminated optical film 1A, and is called the width of the extension direction of the adhesive roll. At the same time, the relative size relationship (width and narrowness) of the width of each film is expressed by the use of "large" and "small".

In the laminated optical film 1A, the third optical film 6 and the resin substrate 21 are removed, and the polarizing plate 10 including the polarizing film 22 and the second optical film (= protective film to be described later) 3 can be used. The polarizing plate 10 may be provided with another optical film such as a protective film through the adhesive layer or the adhesive layer on the side of the peeled resin substrate 21 or the second optical film 3 as needed.

The magnitude relationship or positional relationship of the mutual widths of the first optical film 2, the second optical film 3, the third optical film 6, and the adhesive layer 5 is as described later, and the central axes of the layers in the respective width directions are substantially aligned. That is, in the cross-sectional view shown in Fig. 1, the laminated form is substantially bilaterally symmetrical.

Here, the configuration of each film and the adhesive layer 5 will be described. As the material of the polarizer 22, a known material conventionally used in the production of a polarizing plate can be used, and examples thereof include a polyvinyl alcohol resin, a polyvinyl acetate resin, an ethylene/vinyl acetate (EVA) resin, and a polyamide resin. , polyester resin, and the like. Among them, a polyvinyl alcohol-based resin is preferred. The film-shaped polarizer 22 can be obtained by applying the materials to the stretching treatment, dyeing with iodine or a dichroic dye, and boric acid treatment. The film-shaped polarizer 22 can be cut into an arbitrary size as the first optical film 2, and a laminate in which one or both surfaces of the resin substrate 21 are adhered through the adhesive can be used as the first optical film. 2.

Meanwhile, in the method of forming the polarizer 22, the coating liquid of the material in which the polarizing plate 22 has been dissolved may be applied to a film form (film shape) on one or both sides of the resin substrate 21, and after drying, the entire resin substrate 21 may be dried. The extension treatment is carried out by dyeing with iodine or a dichroic dye and boric acid treatment. Then, the entire resin substrate 21 can be cut into an arbitrary size to be the first optical film 2.

The stretching treatment method may be a longitudinal extension extending in the film length direction (film conveyance direction) or a lateral extension or an oblique extension extending in the film width direction. Examples of the longitudinal stretching method include stretching between rolls, compression stretching, and the like, and a lateral stretching method may be a tenter method or the like. Although the elongation treatment may be any one of a wet extension method and a dry extension method, the extension temperature is selected from a wide range. In other words, it is preferred to use a dry stretching method.

The thickness of the polarizer 22 is preferably 2 to 75 μm, more preferably 2 to 50 μm, and still more preferably 2 to 30 μm.

The resin base material 21 has a role as a support for applying the polarizer 22 to a film-like (film-like) support and a role of protecting the surface of the polarizer 22, and various resin materials can be used. Examples of the material of the resin substrate 21 include a polyethylene terephthalate (PET) resin, a polypropylene resin, and a polycarbonate resin.

The thickness of the resin substrate 21 is preferably from 20 to 500 μm, more preferably from 30 to 300 μm, still more preferably from 50 to 200 μm.

The second optical film 3 is a protective film 3 here, and the third optical film 6 is a temporary protective film 6.

The protective film 3 is a film that prevents the main surface or edge of the polarizing plate 22 from being broken or scratched. Here, the "protective film" refers to a film which can be directly laminated by an adhesive even in a film which can be laminated in various layers on the polarizing film 22.

The protective film 3 can be composed of various transparent resin films known in the field of polarizing plates. For example, a cellulose-based resin which is a representative example of triethyl fluorenyl cellulose, a polyolefin-based resin which is a representative example of a polypropylene-based resin, a cyclic olefin-based resin which is a representative example of a norbornene-based resin, and a polymethyl methacrylate The ester resin is a representative example of an acrylic resin, and a polyethylene terephthalate resin is a representative example of a polyester resin. Among them, cellulose resin is representative.

The protective film 3 may be a film having no optical function, or may be a film having an optical function such as a retardation film or a brightness enhancement film.

The thickness of the protective film 3 is preferably from 5 to 90 μm, more preferably from 5 to 80 μm, still more preferably from 5 to 50 μm.

As the adhesive constituting the adhesive layer 5, various adhesives used in the production of conventional polarizing plates can be used. For example, in terms of weather resistance, refractive index, cationic polymerizability, and the like, an epoxy resin containing no aromatic ring in the molecule is preferred. At the same time, it is preferred to be hardened by irradiation with an active energy ray (ultraviolet rays or hot wires).

The epoxy resin is preferably, for example, a hydrogenated epoxy resin, an alicyclic epoxy resin, an aliphatic epoxy resin or the like. A polymerization initiator (for example, a photocationic polymerization initiator for polymerization by ultraviolet irradiation, a thermal cationic polymerization initiator for polymerization by heat irradiation) or other additives (sensitizer) may be added to the epoxy resin. Etc.), the epoxy resin composition for coating is prepared and used.

Meanwhile, as the adhesive, an acrylic resin such as acrylamide, acrylate, polyurethane acrylate or epoxy acrylate, or a polyvinyl alcohol-based aqueous adhesive can be used.

The polarizing plate 10 is adhered to one or both sides of a display battery (image display element) such as a liquid crystal cell. The polarizing plate may further contain other optical layers laminated on the protective film. Other optical layers include a reflective polarizing film that transmits a polarized light by a certain polarized light, and an anti-glare function film having a concave-convex shape on the surface; a film with a surface anti-reflective function; and a surface having a reflection Functional reflective film; semi-transmissive reflective film with both reflective and transmissive functions; viewing angle compensation film.

Polarized light composed of two layers of polarizer 22 and protective film 3 The thickness of the sheet 10 is preferably from 10 to 500 μm, more preferably from 10 to 300 μm, still more preferably from 10 to 200 μm.

The temporary protective film 6 is used to prevent the adhesive from adhering to the film on the bonding roller, and at the same time, to protect the surface of the member (the first optical film 2) which is laminated with the temporary protective film 6 from damage and abrasion. Wait for the membrane. The material of the temporary protective film 6 can be the same as the above protective film, wherein polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, polybutylene terephthalate A polyester resin such as an ester is preferred.

The temporary protective film 6 may have an adhesive layer which has a weak adhesion which has been laminated on the surface of the film, in addition to the film which becomes a base material.

The thickness of the temporary protective film 6 is preferably 5 to 200 μm, more preferably 5 to 200 μm, still more preferably 5 to 50 μm.

(Manufacturing method of laminated optical film)

As shown in FIGS. 2 and 3, the method for producing the laminated optical film 1A is such that the first optical film 2, the adhesive layer 5, and the protective film 3 are interposed between the pair of bonding rollers 7a and 7b that are rotating. In this order, the first optical film 2 and the protective film 3 are bonded together in a state of being aligned in a direction in which the pair of bonding rollers 7a and 7b are connected. At this time, the temporary protective film 6 is inserted between the bonding roller 7a on the first optical film 2 side and the first optical film 2.

Here, the polarizer 22 in the first optical film 2 is subjected to coating treatment and drying on the resin substrate 21, and then each of the resin substrates 21 is subjected to elongation treatment, dyeing with iodine or a dichroic dye, and boric acid treatment. Wash it, After drying, the width direction edge is cut out so that the resin substrate 21 and the polarizing film 22 are equal in width to each other, and the both ends are aligned, and the adhesive layer 5 is supplied as a coating on the protective film 3. In addition, in FIG. 2, illustration of the adhesive layer 5 is abbreviate|omitted.

The first optical film 2, the protective film 3, and the temporary protective film 6 are laminated to form a laminated body 4A, and the laminated body 4A is followed by curing by the adhesive layer 5, thereby completing the laminated optical film 1A as shown in Fig. 1. .

The existence form of each member at the time of bonding will be described. As shown in Fig. 3, the width of each film or the adhesive layer 5 between the pair of bonding rolls 7a and 7b satisfies the following relationship. Moreover, in Fig. 3, the bonding rolls 7a and 7b are drawn away from the laminated body 4A so that the drawing surface can be easily seen.

‧ The width W _A of the adhesive layer 5 is equal to or greater than the width W ₁ of the first optical film 2 . (W _A ≧W ₁ )

‧ The position of the first optical film 2 in the width direction is within the width W _{A of the} adhesive layer 5 .

‧ The width W ₂ of the protective film 3 is greater than the width W _{A of the} adhesive layer 5 . (W ₂ >W _A )

‧ Protective film 3 is in the presence width W _{A of the} inner adhesive layer 5 .

‧ The width W ₃ of the temporary protective film 6 is greater than the width W _{A of the} adhesive layer 5 . (W ₃ >W _A )

‧ The temporary protective film 6 is inserted into the presence width W _{A of the} inner adhesive layer 5 .

The term "inner package" as used herein means that both end portions of the member having the width side of the width side are more outward in the width direction than the members on the narrow side of the width.

Further, the relationship between the width of the protective film 3 and the width of the temporary protective film 6 is arbitrary.

At the same time, the manufacturing method of the first embodiment satisfies the following relationship although it is not necessary.

The width W _R1 of the bonding roller 7a on the first optical film 2 side is smaller than the width W _{3 of the} temporary protective film 6. (W ₃ >W _R1 )

The bonding roller 7a on the side of the first optical film 2 is positioned in the width direction W ₃ of the temporary protective film 6.

The width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{A of the} adhesive layer 5. (W _R2 >W _A )

The bonding roller 7b on the side of the protective film 3 is located at the width W _A of the adhesive inner layer 5 in the width direction.

The width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{2 of the} protective film 3. (W _R2 >W ₂ )

The bonding roller 7b on the side of the protective film 3 has a width W _{2 which} is located on the side of the inner protective film 3 in the width direction.

Here, the "width of the bonding roller" refers to the full width of the portion that is extended while maintaining the same diameter as the portion of the effective contact surface that contributes to bonding. For example, when a portion of the width direction of the edge portions of the bonding rollers 7a, 7b is reduced in diameter, and a portion not contacting the first optical film 2 or the protective film 3 is removed, the portion of the reduced diameter is removed. The width of the portion is taken as the full width of the bonding rolls 7a, 7b.

The width W _R1 of the bonding roller 7a on the first optical film 2 side is preferably smaller than the width W _{A of the} adhesive layer 5, and is preferably smaller than the width W _{1 of the} first optical film 2. Meanwhile, the width W _R1 of the bonding roller 7a is preferably 1 to 100 mm smaller than the width W _{3 of} the third optical film 6, and more preferably 1 to 50 mm.

According to this manufacturing method, when the first optical film 2 and the protective film 3 are bonded, a protective film 3 having a wider insertion width than the adhesive layer 5 is formed between the adhesive layer 5 and the bonding rolls 7a and 7b. Since the film 6 is temporarily protected, it is possible to prevent the bonding rolls 7a and 7b from being contaminated by the adhesive.

In the manufacturing method, the width W _R1 of the bonding roller 7a on the first optical film 2 side is smaller than the width W _{3 of the} temporary protective film 6, and the bonding roller 7a on the first optical film 2 side is in the width direction. Since the position is within the existence width W ₃ of the temporary protective film 6, the adhesion roller 7a can be further prevented from being contaminated by the adhesive.

At the same time, the resin substrate 21 and the polarizer 22 constituting the first optical film 2 are aligned at the ends with the same width. Therefore, the thickness of the edge of the first optical film 2 in the width direction is stable.

At the same time, since the width W _A of the adhesive layer 5 is equal to or larger than the width W ₁ of the first optical film 2 (W _A ≧W ₁ ), when the resin substrate 21 is peeled off from the polarizing film 22, the polarizing plate 22 can be prevented from being torn. .

Further, in the first embodiment, the width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W ₂ of the protective film 3, but the width of the bonding roller 7b may be smaller than the width W of the protective film 3. ₂ . At this time, the bonding roller 7b is located within the existence width W ₂ of the protective film 3. Thereby, the adhesive roller 7b can be further prevented from being contaminated by the adhesive.

<Second embodiment>

Hereinafter, a second embodiment of the present invention will be described. The difference from the first embodiment will be mainly described.

(layered optical film)

As shown in Fig. 4, the laminated optical film 1B produced by the method for producing a laminated optical film of the second embodiment does not include the third optical film 6.

(Manufacturing method of laminated optical film)

As shown in FIGS. 5 and 6, the method of manufacturing the laminated optical film 1B is such that the first optical film 2, the adhesive layer 5, and the protective film 3 are interposed between the pair of bonding rollers 7a and 7b that are rotating. This order is introduced in a state of being aligned in a direction connecting the pair of bonding rolls 7a and 7b, and the first optical film 2 and the protective film 3 are bonded together.

The first optical film 2 and the protective film 3 are laminated to form a laminated body 4B, and the laminated body 4B is thereafter cured by the adhesive layer 5 to complete the laminated optical film 1B shown in FIG.

The existence form of each member at the time of bonding will be described. As shown in Fig. 6, the width of each of the films, the adhesive layer 5, and the bonding roller 7a between the pair of bonding rolls 7a and 7b satisfies the following relationship. Further, in Fig. 6, in order to make the drawing easy to see, the bonding rolls 7a and 7b are separated from the laminated body 4B and drawn.

‧ The width W _A of the adhesive layer 5 is equal to or greater than the width W ₁ of the first optical film 2 . (W _A ≧W ₁ )

‧ The position of the first optical film 2 in the width direction is within the width W _{A of the} adhesive layer 5 .

‧ The width W ₂ of the protective film 3 is greater than the width W _{A of the} adhesive layer 5 . (W ₂ >W _A )

‧ Protective film 3 is in the presence width W _{A of the} inner adhesive layer 5 .

The width W _R1 of the bonding roller 7a on the first optical film 2 side is smaller than the width W _{1 on the} first optical film 2 side. (W ₁ >W _R1 )

2 ‧ first side of the optical film bonding roller 7a, the position in the width direction based on the presence of the first optical film 2 within the width W _1.

Here, the width W _R1 of the bonding roller 7a on the first optical film 2 side is preferably 1 to 200 mm smaller than the width W _{1 of the} first optical film 2, and more preferably less than 1 to 100 mm.

At the same time, the manufacturing method of the second embodiment is not necessarily a necessary condition, but satisfies the following relationship.

The width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{A of the} adhesive layer 5. (W _R2 >W _A )

The bonding roller 7b on the side of the protective film 3 is located at the width W _A of the adhesive inner layer 5 in the width direction.

The width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{2 of the} protective film 3. (W _R2 >W ₂ )

The bonding roller 7b on the side of the protective film 3 has a width W _{2 which} is located on the side of the inner protective film 3 in the width direction.

According to this manufacturing method, although the adhesive layer 5 is overflowed by the existence width of the first optical film 2, the width W _R1 of the bonding roller 7a on the first optical film 2 side is smaller than the width W of the first optical film 2. 7a-based adhesive roller position ₁ in the width direction, and the first side of the optical film 2 in the presence of the first optical film 2 within the width W _1, can be prevented by the tacking roller 7a of the adhesive caused contamination.

Further, in the second embodiment, the width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{2 of the} protective film 3, but the width W _{R2 of the} bonding roller 7b may be made smaller than the protective film 3. The width W ₂ is the same as that in the first embodiment.

<Third embodiment>

Hereinafter, a third embodiment of the present invention will be described. The difference from the second embodiment will be mainly described.

(layered optical film)

As shown in Fig. 7, the laminated optical film 1C manufactured by the method for producing a laminated optical film according to the third embodiment has a width larger than the width of the adhesive layer 5 of the first optical film 2.

Further, the magnitude relationship or positional relationship of the mutual widths of the first optical film 2, the protective film 3, and the adhesive layer 5 is as described later, and the central axes of the layers in the respective width directions are substantially aligned. That is, in the cross-sectional view shown in Fig. 7, the laminated form is substantially bilaterally symmetrical.

(Manufacturing method of laminated optical film)

The manufacturing method of the laminated optical film 1C is the first optical film 2 between the pair of bonding rolls 7a and 7b which rotates, as shown in FIG. 5 and FIG. The adhesive layer 5 and the protective film 3 are introduced in this order in a direction in which the pair of bonding rollers 7a and 7b are connected, and the first optical film 2 and the protective film 3 are bonded together.

The first optical film 2 and the protective film 3 are laminated to form a laminated body 4C, and the laminated body 4C is followed by the curing of the adhesive layer 5 to complete the laminated optical film 1C shown in FIG.

Explain the existence form of each member at the time of bonding. As shown in Fig. 8, the width of each film and the adhesive layer 5 between the pair of bonding rolls 7a and 7b satisfies the following relationship. Further, in Fig. 8, the bonding rolls 7a and 7b are separated from the laminated body 4C and drawn so that the drawing surface is easily viewed.

‧ The width W _{A of the} adhesive layer 5 does not reach the width W _{1 of the} first optical film 2 . (W ₁ >W _A )

‧ The position of the adhesive layer 5 in the width direction is within the existence width W ₁ of the first optical film 2 .

‧ The width W ₂ of the protective film 3 is greater than the width W _{A of the} adhesive layer 5 . (W ₂ >W _A )

‧ Protective film 3 is located at the presence width W _A of the inner encapsulant layer 5 .

Here, the width W _{A of the} adhesive layer 5 is preferably 0.1 to 50 mm smaller than the width W _{1 of the} first optical film 2, and more preferably 0.1 to 20 mm, and more preferably 0.1 to 5 mm. . At this time, the first optical film 2 and the protective film 3 can be sufficiently adhered to the edge in the width direction.

Further, although the width W 2 of the first optical film width W 3 of an arbitrary size based relationship of _{1 2} and the protective film, but in this system to be the same. (W ₁ = W ₂ )

Meanwhile, the manufacturing method of the third embodiment is not essential, but satisfies the following relationship.

‧ two bonding roll width W _R1 7a, 7b is, W _R2, respectively, larger than the first line width W 2 of the optical film and the protective film ₁ of a width W 3 _2. (W _R1 >W ₁ and W _R2 >W ₂ )

‧ two bonding rolls 7a, 7b, the position in the width direction of the lines are located within the first optical film bag 2 is present and the second width W ₁ of the optical film 3 present a width W _2.

Although the magnitude relationship of the widths of the two bonding rolls 7a and 7b is arbitrary, it is the same here. (W _R1 = W _R2 )

According to this manufacturing method, since the possibility that the adhesive layer 5 overflows the width of the first optical film 2 and the protective film 3 is extremely small, it is possible to prevent the bonding rolls 7a and 7b from being contaminated by the adhesive.

Further, in this third embodiment, although the display tacking roller width W _R1 7a, 7b is, W _R2 are greater than the first optical film width W 2 of ₁ and the protective film width W 3 of _2, but the adhesive roll 7a, 7b also smaller than the width of the first optical film ₁ and the width W 2 of width W 3 of the protective film ₂ can also be smaller than the width W _a of the adhesive layer 5. In this case, bonding rollers 7a, 7b, which are located based on presence of the optical film 2 within the width W _1, the protective film 3 is present within the width W _2. Thereby, it is possible to further prevent the bonding rollers 7a, 7b from being contaminated by the adhesive.

Meanwhile, in the third embodiment, the adhesive layer 5 may be applied to the protective film 3 in the same manner as in the first embodiment. However, the adhesive layer 5 may be applied to the polarizer 22 as well. On the side.

(Modification of the first to third embodiments)

The first to third embodiments described above can also be implemented in the following aspects. In other words, the first optical film 2 is a polarizing plate (for example, a polarizing plate having a configuration of the polarizing plate 10 shown in Fig. 1), and the second optical film 3 is a separating piece, and the film is replaced by an adhesive instead of an adhesive. The shape of the bond. At this time, the laminated optical film was used to manufacture a polarizing plate with a separator. This form will be described below.

The adhesive layer is a layer that functions when the polarizing plate is bonded to other articles such as a liquid crystal cell. The adhesive layer may be composed of an acrylic resin, a polyoxymethylene resin, a polyester, a polyurethane, a polyether or the like.

The thickness of the adhesive layer is preferably from 2 to 500 μm, more preferably from 2 to 200 μm, still more preferably from 2 to 50 μm.

The method of laminating the adhesive layer on the polarizing plate may be, for example, a method of coating a solution containing the above resin or any additive component on a polarizing plate, or laminating the polarizing plate after forming an adhesive layer on the separation sheet with the solution. On the method.

The release sheet is a peelable film that is adhered for the purpose of protecting the adhesive layer or preventing adhesion of foreign matter, etc., and peeling off the polarizing plate to expose the adhesive layer. The separator may be composed of, for example, a polyethylene-based resin such as polyethylene, a polypropylene-based resin such as polypropylene, a polyester-based resin such as polyethylene terephthalate, or the like. Among them, a stretch film of polyethylene terephthalate is preferred.

The separator sheet can be easily peeled off when the polarizing plate is used, and can be applied to the surface of the adhesive layer by a polyoxyl resin or the like. Release treatment.

The thickness of the separator is preferably from 10 to 500 μm, more preferably from 10 to 300 μm, still more preferably from 10 to 200 μm.

Even in the above-described embodiment, the bonding rollers 7a and 7b can be prevented from being contaminated by the adhesive by the same action as in the above embodiment.

When a polarizing plate is used as the first optical film 2, a protective film may be usually laminated on one or both sides of the polarizing plate by using an adhesive. When the protective film is laminated only on the polarizing plate on one surface of the polarizer, the protective film may be laminated on the side opposite to the side on which the layer is laminated to form the adhesive layer side. The polarizing plate may also contain other optical layers laminated on the protective film or a protective layer that protects the surface of the protective film. Other optical layers include a reflective polarizing film that transmits a polarized light that reflects a property opposite thereto, a film with an anti-glare function having a concave-convex shape on the surface, and a film that is resistant to a surface reflecting function; Reflective film of reflective function; semi-transmissive reflective film with both reflective and transmissive functions; viewing angle compensation film. As the protective layer for protecting the surface of the protective film, a usual transparent resin film can be used. For example, a cellulose-based resin which is a representative example of a triethyl fluorenyl cellulose, a polyolefin-based resin which is a representative example of a polypropylene-based resin, a cyclic olefin-based resin which is a representative example of a decene-based resin, and a polymethyl group The acrylic acid-based resin is a representative example of an acrylic resin, and a polyethylene terephthalate resin is a representative example of a polyester resin. The protective layer for protecting the surface of the protective film may be a film having no optical function, or a film having an optical function of a retardation film and a brightness enhancement film at the same time.

<Fourth embodiment>

Hereinafter, a fourth embodiment of the present invention will be described. The difference from the second embodiment will be mainly described.

(layered optical film)

As shown in Fig. 9, the laminated optical film 1D manufactured by the method for producing a laminated optical film of the fourth embodiment is such that the widths of the resin substrate 21 and the polarizer 22 in the first optical film 2 are not aligned, and the resin base The width of the material 21 is greater than the width of the polarizer 22.

Further, the magnitude relationship or positional relationship of the mutual widths of the resin substrate 21, the polarizer 22, the protective film 3, and the adhesive layer 5 is as described later, and the central axes of the layers in the respective width directions are substantially aligned. That is, in the cross-sectional view shown in Fig. 9, the laminated form is substantially bilaterally symmetrical.

(Manufacturing method of laminated optical film)

As shown in FIGS. 5 and 10, the method of manufacturing the laminated optical film 1D is to laminate the resin substrate 21, the polarizer 22, the adhesive layer 5, and the protective film between the pair of bonding rollers 7a and 7b that are rotating. 3 is introduced in this order in a state of being aligned in a direction connecting the pair of bonding rollers 7a and 7b, and the polarizer 22 is bonded to the protective film 3.

Here, in the polarizer 22 of the first optical film 2, only the central portion and both end portions of the resin substrate 21 in the web direction are dried without being applied, and the entire resin substrate 21 is subjected to elongation treatment. It is supplied by dyeing and boric acid treatment by iodine or a dichroic dye, washing with water, and drying.

The resin substrate 21, the polarizer 22, and the protective film 3 are accumulated The layer is formed into a layered body 4D, and the layered body 4D is thereafter cured by the adhesive layer 5 to complete the laminated optical film 1D shown in Fig. 9.

Explain the existence form of each member at the time of bonding. As shown in Fig. 10, the width of each film and the adhesive layer 5 between the pair of bonding rolls 7a and 7b satisfies the following relationship. Further, in Fig. 10, the bonding rolls 7a and 7b are separated from the laminated body 4D and drawn so that the drawing surface is easily viewed.

The width W _{12 of the} polarizer 22 is smaller than the width W _{11 of the} resin substrate 21. (W ₁₁ >W ₁₂ )

The width W _{A of the} adhesive layer 5 is greater than or equal to the width W ₁₂ of the polarizer 22 and smaller than the width W _{11 of the} resin substrate 21. (W ₁₁ >W _A ≧W ₁₂ )

‧ resin base material 21 lines the inner bit packet presence polarizer 22 and the width W ₁₂ of the presence of adhesive layer 5 a width W _A.

‧ The width W _{2 of the} protective film 3 is greater than the width W _{A of the} adhesive layer 5 . (W ₂ >W _A )

‧ Protective film 3, the presence width W _{A of the} inner adhesive layer 5 is tied.

Further, the relationship between the width W _{12 of the} resin substrate 21 and the width W ₂ of the protective film 3 is arbitrary.

Meanwhile, the manufacturing method of the fourth embodiment is not essential, but satisfies the following relationship.

The width W _R1 of the bonding roller 7a on the side of the resin substrate 21 is smaller than the width W _{11 of the} resin substrate 21. (W ₁₁ >W _R1 )

‧ The position of the bonding roller 7a on the resin substrate 21 side in the width direction is within the width of the resin substrate 21.

The width W _R2 of the bonding roller 7b on the side of the protective film 3 is larger than the width W _{2 of the} protective film 3. (W _R2 >W ₂ )

‧ The adhesive roller 7b on the side of the protective film 3 is located at the position in the width direction and has a width W _{2 on the} side of the protective film 3 .

Here, the width W _R1 of the bonding roller 7a on the resin substrate 21 side is preferably smaller than the width W _{A of the} adhesive layer 5, and more preferably smaller than the width W _{12 of the} polarizing plate 22. Meanwhile, the width W _{R1 of the} bonding roller 7a is preferably 1 to 100 mm smaller than the width W _{12 of the} resin substrate 21, and more preferably 1 to 50 mm.

When the polarizer 22 is bonded to the protective film 3 by this manufacturing method, the resin substrate 21 or the protective film 3 having a width larger than that of the adhesive layer 5 is interposed between the adhesive layer 5 and the bonding rollers 7a and 7b. Therefore, the bonding rolls 7a, 7b can be prevented from being contaminated by the adhesive.

In the manufacturing method, the width W _R1 of the bonding roller 7a on the resin substrate 21 side is smaller than the width of the resin substrate 21, and the bonding roller 7a on the resin substrate 21 side is a resin substrate in the width direction. The presence of 21 is within the width W ₁₁ , so that the adhesion roller 7a can be further prevented from being contaminated by the adhesive.

In the fourth embodiment described above, the first optical film 2 may be a polarizing plate. The polarizing plate may be one in which a protective film is laminated by passing an adhesive on one or both sides of the polarizer. Further, the polarizer may be smaller than the width of the protective film and may be present within the width of the protective film. When the protective film is laminated only on the polarizing plate on one surface of the polarizer, the protective film may be laminated on the side opposite to the side of the laminated layer to form the adhesive layer side. The polarizing plate may further contain other optical layers laminated on the protective film or protect the surface of the protective film. Floor. Other optical layers include a reflective polarizing film that reflects a polarized light having opposite properties through a certain polarized light; an anti-glare film having a concave-convex shape on the surface; a film that resists surface reflection; and a surface having reflection Functional reflective film; semi-transmissive reflective film with both reflective and transmissive functions; viewing angle compensation film. As the protective layer for protecting the surface of the protective film, a usual transparent resin film can be used. For example, a cellulose-based resin which is a representative example of a triethyl fluorenyl cellulose, a polyolefin-based resin which is a representative example of a polypropylene-based resin, a cyclic olefin-based resin which is a representative example of a decene-based resin, and a polymethyl group The acrylic acid-based resin is a representative example of an acrylic resin, and a polyethylene terephthalate resin is a representative example of a polyester resin. The protective layer for protecting the surface of the protective film may be a film having no optical function, or a film having an optical function of a retardation film and a brightness enhancement film at the same time.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

For example, in each of the above embodiments, the polarizer 22 is applied to one surface of the resin substrate 21, but the polarizer 22 may be applied to both surfaces of the resin substrate 21. At this time, after the laminated optical films 1A to 1D are produced, the polarizing film remaining on the resin substrate 21 side can be used for another by peeling between the polarizing plate 22 facing the adhesive layer 5 and the resin substrate 21. The manufacture of polarizing plates.

Meanwhile, in each of the above embodiments, the first optical film in which the polarizing plate 22 is provided on one surface of the resin substrate 21 is used. However, the polarizing plate 22 may be provided on one surface or both surfaces of the resin substrate 21. Other optical functional layers. An optical functional layer other than the polarizer 22, The phase difference layer, the viewing angle compensation layer, and the like can be provided on the resin substrate 21 by applying and drying a liquid in which a material having a desired optical function is dissolved or dispersed.

2‧‧‧1st optical film

3‧‧‧Protective film (2nd optical film)

4A‧‧‧Layer

5‧‧‧ adhesive layer

6‧‧‧ Temporary protective film (3rd optical film)

7a‧‧‧1st optical film side adhesive roller

7b‧‧‧Adhesive roll on the protective film side

21‧‧‧Resin substrate

22‧‧‧ polarizer

W ₁ ‧‧‧The width of the first optical film

W ₂ ‧‧‧Width of protective film

W ₃ ‧‧‧ Temporary protective film width

W _A ‧‧‧The width of the adhesive layer

W _R1 ‧‧‧The width of the bonding roller on the 1st optical film side

W _R2 ‧‧‧Width of the adhesive roller on the protective film side

Claims (13)

A method for producing a laminated optical film, wherein a first optical film, an adhesive layer or an adhesive layer and a second optical film are sequentially connected between the pair of bonding rollers in a row between a pair of bonding rollers that are rotating When the first optical film is bonded to the second optical film, the width of the adhesive layer or the adhesive layer is greater than or equal to the width of the first optical film, and the first is introduced. The position in the width direction of the optical film is within the width of the adhesive layer or the adhesive layer, and the width of the second optical film is larger than the width of the adhesive layer or the adhesive layer, and the second optical film is positioned. Including the presence of the adhesive layer or the adhesive layer, the width of the adhesive layer between the first optical film side and the first optical film is larger than the width of the adhesive layer or the adhesive layer. The third optical film is interposed so as to encapsulate the width of the adhesive layer or the adhesive layer. The method for producing a laminated optical film according to the first aspect of the invention, wherein the width of the bonding roller on the first optical film side is smaller than a width of the third optical film, and the bonding on the first optical film side The position of the roller in the width direction is within the width of the third optical film. A method for producing a laminated optical film, wherein a first optical film, an adhesive layer, an adhesive layer, and a second optical film are sequentially connected to each other between the pair of bonding rolls in a row between a pair of bonds in rotation The first optical film is bonded to the second optical film, and the width of the adhesive layer or the adhesive layer is greater than or equal to the width of the first optical film during the bonding, and the first optical The position in the width direction of the film is within the width of the adhesive layer or the adhesive layer, and the width of the second optical film is larger than the width of the adhesive layer or the adhesive layer, and the second optical film is located inside. The width of the adhesive layer on the first optical film side is smaller than the width of the first optical film, and the width of the adhesive film on the first optical film side is a width direction. The position is within the width of the first optical film. A method for producing a laminated optical film, wherein a first optical film, an adhesive layer or an adhesive layer and a second optical film are sequentially connected between the pair of bonding rolls in a sequence between a pair of bonding rolls that are rotating When the first optical film is bonded to the second optical film and bonded to each other, the width of the adhesive layer or the adhesive layer is less than the above. The width of the first optical film, the position of the adhesive layer or the adhesive layer in the width direction is within the width of the first optical film, and the width of the second optical film is larger than the adhesive layer or the adhesive layer. The width of the second optical film is such that the adhesive layer or the adhesive layer is present in a width. The method for producing a laminated optical film according to the fourth aspect of the invention, wherein the width of the bonding roller on the first optical film side is smaller than a width of the first optical film, and the side of the first optical film side The position of the bonding roller in the width direction is within the width of the first optical film. The method for producing a laminated optical film according to claim 4, wherein the width of the adhesive layer or the adhesive layer is 0.1 to 50 mm smaller than the width of the first optical film. The method for producing a laminated optical film according to any one of claims 1 to 6, wherein the first optical film has a resin substrate and an optical functional layer provided on one or both sides of the resin substrate The resin substrate and the optical functional layer are aligned at equal widths to each other, and the first optical film is disposed on the optical functional layer side toward the adhesive layer or the adhesive layer side, and the second optical The film is a protective film. The manufacturer of the laminated optical film as described in claim 7 of the patent application scope The method wherein the optical functional layer is a polarizer. The method for producing a laminated optical film according to claim 8, wherein the polarizer is applied to the resin substrate. A method for producing a laminated optical film, wherein a resin substrate, an optical functional layer, an adhesive layer or an adhesive layer provided on one or both sides of the resin substrate is protected between a pair of bonding rolls that are rotating The film is introduced in a state in which the film is aligned in a direction connecting the pair of bonding rolls, and the optical function layer is bonded to the protective film. When the film is bonded, the width of the optical function layer is smaller than that of the resin substrate. Width, the width of the adhesive layer or the adhesive layer is greater than or equal to the width of the optical functional layer, and is smaller than the width of the resin substrate, and the resin substrate is located inside the optical functional layer and the adhesive layer or The width of the adhesive layer is greater than the width of the adhesive layer or the adhesive layer, and the protective film is located in the presence of the adhesive layer or the adhesive layer. The method for producing a laminated optical film according to claim 10, wherein a width of the bonding roller on the resin substrate side is smaller than a width of the resin substrate, and the bonding roller on the resin substrate side is Position in the width direction It is within the width of the presence of the aforementioned resin substrate. The method for producing a laminated optical film according to claim 10, wherein the optical functional layer is a polarizer. The method for producing a laminated optical film according to claim 12, wherein the polarizer is applied to the resin substrate.