TW202045654A - Optical laminated film with adhesive layer and method for producing the same - Google Patents

Abstract

An objective of the present invention is to provide an optical laminated film with adhesive layer in which generation of cracks is suppressed.

As a solution, the optical laminated film with adhesive layer of the present invention has an optical laminated film including a polarizer layer in which a dichroic dye is adsorbed and oriented, and an adhesive layer in this order, wherein at least a part of a side surface of the optical laminated film with adhesive layer is a protective region in which the adhesive layer protrudes outward from the extreme end position of the polarizer layer and warps toward the polarizer layer side.

Description

Optical laminated film with adhesive layer and manufacturing method thereof

The present invention relates to an adhesive layer-attached optical laminated film and its manufacturing method.

In recent years, the design of image display devices has continued to diversify. Affected by this trend, optical laminated films including linear polarizing films are also required to be able to correspond to various shapes. Japanese Patent Application Laid-Open No. 2018-25630 discloses a polarizing plate having a shape with a concave portion at the outer edge portion, and a polarizing plate having a shape with a through hole in the plane.

[Prior Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Patent Application Publication No. 2018-25630.

The optical laminated film having a shape with a concave portion at the outer edge portion and the optical laminated film having a shape with a through hole in the surface have a problem that cracks are likely to occur.

The object of the present invention is to provide an optical laminated film with an adhesive layer that suppresses cracking and a method of manufacturing the same.

The present invention provides the following optical laminated film with an adhesive layer and a manufacturing method of the optical laminated film with an adhesive layer.

[1] An optical laminated film with an adhesive layer, which has an optical laminated film and an adhesive layer in sequence,

Wherein, the aforementioned optical multilayer film includes a polarizer layer with dichroic pigments adsorbed and aligned,

At least a part of the side surface of the optical laminated film with the adhesive layer is a protection area,

In the protection area, the adhesive layer protrudes to the outside than the outermost position of the polarizer layer, and is raised toward the polarizer layer side.

[2] The optical laminate film with an adhesive layer as described in [1], wherein at least a part of the side surface of the optical laminate film with the adhesive layer is a curved area, and in the curved area, the optical laminate film and The contour of the surface on the opposite side of the adhesive layer side is curved,

At least a part of the aforementioned curved area is the aforementioned protected area.

[3] The optical laminate film with an adhesive layer as described in [2], wherein the protection area in the curved area includes: the angle θ formed by the contour and the absorption axis direction of the polarizer layer is continuously Changes, and the aforementioned angle θ exceeds 0° and is below 90°.

[4] The optical laminated film with an adhesive layer as described in any one of [1] to [3], wherein the protective region is a cut surface.

[5] The optical laminated film with an adhesive layer as described in any one of [1] to [4], wherein the protection area includes: the outermost position of the adhesive layer and the outermost end of the polarizer layer Between locations The area where the distance d is 10μm or more.

[6] The optical laminated film with an adhesive layer as described in any one of [1] to [5], wherein the adhesive layer on the opposite side of the optical laminated film side further has: peelable Ground bonded separation film (separate film).

[7] The optical laminated film with an adhesive layer as described in any one of [1] to [6], wherein the optical laminated film has a liquid crystal hardening layer, and the liquid crystal hardening layer is made of a polymerizable liquid crystal compound Composed of polymer hardened material.

[8] The optical laminated film with an adhesive layer as described in any one of [1] to [7], wherein the optical laminated film is on the side opposite to the adhesive layer when viewed from the polarizer layer Has a protective layer,

The protective layer has a hard coat layer, and the hard coat layer constitutes a surface on the side opposite to the polarizer layer side.

[9] A manufacturing method of optical laminated film with adhesive layer, which has the following steps:

The step of preparing the raw material laminated film. The raw material laminated film has an optical laminated film, an adhesive layer, and a separation film in sequence. The optical laminated film includes a polarizer layer with a dichroic pigment adsorbed and aligned, and the separation film is peelable Groundly adhere to the aforementioned adhesive layer; and

In the cutting step, an etching knife is introduced from the side of the separation film with respect to the raw material laminated film to cut the raw material laminated film to form a side surface.

[10] The method of manufacturing an optical laminated film with an adhesive layer as described in [9], wherein at least a part of the side surface is a protected area, and in the protected area, the adhesive layer is larger than the polarizer layer The outermost position protrudes further to the outside and is raised toward the polarizer layer side.

According to the present invention, it is possible to provide an optical laminated film with an adhesive layer that suppresses cracking.

20: Optical laminated film

20a: surface

21: Polarizer layer

22: The first protective layer

23: 2nd protective layer

24: Surface protective film

25: The first bonding layer

26: The first liquid crystal hardened layer

27: The second bonding layer

28: The second liquid crystal hardened layer

31: Adhesive layer

32: separation membrane

51: Through hole

52: corner

53: Concave

100, 110, 120, 130: Optical laminated film with adhesive layer

140: Optical laminated film with adhesive layer, optical laminated film with adhesive layer

100a, 130a, 140a: protected area

121: Etching knife mold

122: Etching Knife

122a: knife point

122b: body

150: Raw material laminated film

160: support plate

d: distance

Fig. 1 is a schematic cross-sectional view schematically showing an example of the adhesive layer-attached optical laminated film of the present invention.

Fig. 2 is a plan view showing an example of an adhesive layer-attached optical laminate film having a curved area on the side surface.

Fig. 3 is a plan view showing another example of an adhesive layer-attached optical laminated film having a curved area on the side surface.

FIG. 4 is a schematic cross-sectional view schematically showing the adhesive layer-attached optical laminate film of the first embodiment.

Fig. 5 is a schematic cross-sectional view schematically showing an adhesive layer-attached optical laminate film of the second embodiment.

Fig. 6 is a plan view showing an example of the etching die.

Fig. 7 is a cross-sectional view of the etching knife shown in Fig. 6.

Fig. 8 is a cross-sectional view schematically showing the cutting step of the manufacturing method of the present invention.

Fig. 9 is a cross-sectional view schematically showing an example of the cross-sectional shape of the etching knife.

Fig. 10 is a cross-sectional view schematically showing an example of the cross-sectional shape of the etching knife.

Fig. 11 is a cross-sectional view schematically showing an example of the cross-sectional shape of the etching knife.

Figure 12 is a cross-sectional view schematically showing the observation image of the cross-sections of the adhesive layer-attached optical laminate film A and B using an optical microscope image.

Fig. 13 is a cross-sectional view schematically showing the observation image of the cross-section of the adhesive layer-attached optical laminate film C and D with an optical microscope image.

Figure 14 is an optical microscope image of the upper surface of the optical laminated film A and B with the adhesive layer attached.

Figure 15 is a schematic diagram showing the method of measuring the pushing force.

Figure 16 shows the measurement results of the pushing force.

[Optical laminated film with adhesive layer]

Fig. 1 is a schematic cross-sectional view schematically showing an example of the adhesive layer-attached optical laminated film of the present invention. As shown in FIG. 1, the adhesive layer-attached optical laminate film 100 has an optical laminate film 20 and an adhesive layer 31 in this order. The optical laminate film 20 includes a polarizer layer 21 with a dichroic pigment adsorbed and aligned.

At least a part of the side surface of the optical laminated film 100 with the adhesive layer is a protection area. In this specification, the “protected area” refers to the side area of the adhesive layer 31 protruding to the outside than the outermost end position of the polarizer layer 21 and warped toward the polarizer layer 21 side. Regarding the range of the "side area" in this specification, all positions juxtaposed in the stacking direction in the side surface are considered to be included in the same area. In this specification, "turning up to the side of the polarizer layer 21" refers to the part having the protruding part of the adhesive layer 31 closer to the side of the polarizer layer 21 than other parts. The protruding part of the adhesive layer 31 is close to the side of the polarizer layer 21, and the adhesive layer 31 can be in contact with all the sides of the polarizer layer 21 or a part of the sides of the polarizer layer 21, or as shown in Figure 1, the adhesive The layer 31 is not in contact with the side surface of the polarizer layer 21 but is curved toward the polarizer layer 21 side. The side area 100a shown in FIG. 1 is a protection area.

The optical laminated film 100 with an adhesive layer can prevent cracking by having a protective region 100a on the side surface. In the protected area 100a, it is presumed that the optical fiber is protected by the adhesive layer 31 The side surface of the laminated film 20 prevents cracking. It is easy to crack from the side surface or the vicinity of the side surface as the starting point.

In the side surface of the optical laminated film 100 with the adhesive layer, at least a part of the area is required to be the protected area 100a, but from the viewpoint of suppressing the occurrence of cracks, it is preferable that the ratio of the area to the protected area 100a is higher. Alternatively, it is preferable that the side area where cracks easily occur is the protection area 100a. For example, more than 10% of the entire area of the side surface of the optical laminated film 100 with the adhesive layer is the protection area 100a. Or, for example, at least a part of the curved area of the side surface of the optical laminated film 100 with the adhesive layer includes the protected area 100a, and more than 50% of the entire area of the curved area is the protected area 100a.

In this specification, the "curved area" refers to the area where the contour of the surface 20a on the side opposite to the adhesive layer 31 side of the optical laminated film 20 is the side surface of the curve. Here, the “curve” refers to the angle θ formed with the absorption axis direction of the polarizer layer 21 continuously changing. In the curved area, cracks are likely to occur starting from the side surface or near the side surface.

Fig. 2 is a plan view showing an example of an adhesive layer-attached optical laminate film having a curved area on the side surface. Fig. 2 is a plan view of the adhesive layer-attached optical laminated film 110 viewed from the surface on the side opposite to the adhesive layer side. The optical laminated film 110 with an adhesive layer shown in FIG. 2 has a rounded quadrangular shape and has a through hole 51. A rounded quadrilateral shape refers to a shape in which one or more corners of the quadrilateral shape are curved, that is, one or more corners of the quadrilateral shape are rounded. All corners 52 of the optical laminated film 110 with the adhesive layer are rounded corners. In the optical laminated film 110 with an adhesive layer shown in FIG. 2, the inner wall of the through hole 51 and the side surface of the corner 52 have curved areas. The angle θ formed by the contour of the curved area and the direction of the absorption axis of the polarizer layer changes continuously.

Figure 3 shows the optical laminate film with an adhesive layer on the side surface area Top view of another example. FIG. 3 is a plan view of the adhesive layer-attached optical laminated film 120 viewed from the surface on the side opposite to the adhesive layer side. The optical laminated film 120 with an adhesive layer shown in FIG. 3 has a rounded quadrangular shape, and has a concave portion 53 on the outer edge. In the optical laminated film 120 with an adhesive layer shown in FIG. 3, the side surfaces of the concave portion 53 and the corner portion 52 of the outer edge have curved areas. The angle θ formed by the contour of the curved area and the absorption axis of the polarizer layer changes continuously.

In plan view, the optical laminated film with the adhesive layer can be rounded or quadrangular as shown in Figs. 2 and 3. The so-called quadrilateral shape refers to a shape in which all four corners are not rounded. In addition, in this specification, the quadrangular shape means a rectangular shape or a square shape.

The angle θ formed by the profile of the side surface on the surface 20a and the absorption axis direction of the polarizer layer 21 is 0° to 90°, and the area where the angle θ continuously changes is a curved area. The curved area includes the part where the angle θ exceeds 0° and is below 90°. The curved surface area including such a portion is likely to crack from the side surface or the vicinity of the side surface as a starting point, and therefore, the crack generation suppression effect of the present invention can be significantly exerted.

In Figure 1, in the protective area 100a of the optical laminated film 100 with the adhesive layer, the distance d between the outermost position of the adhesive layer 31 and the outermost position of the polarizer layer 21 is shown. The protection area 100a preferably includes an area with a distance d of 10 μm or more, and more preferably includes an area with a distance d of 15 μm or more. In such an area, it is easier to suppress cracks. In the protective region 100a, the distance d between the outermost position of the adhesive layer 31 and the outermost position of the polarizer layer 21 is, for example, 30 μm or less.

In the optical laminated film 100 with an adhesive layer, the side surface having the protective region 100a is, for example, a cut surface formed by cutting the laminated body with a dicing knife. By adjusting the cutting knife used for cutting, the cutting direction, the cutting speed, the in-plane tension imparted to the laminate during cutting, etc., a side surface with a protected area can be formed. The adhesive layer 31 is higher than the polarizer layer 21 The outermost position protrudes further to the outside and is tilted toward the polarizer layer 21 side. As far as the cutting knife is concerned, if you use an etching knife (minare (Pinnacle blade)), the adhesive layer 31 can be protruded and raised, and the above-mentioned protective region 100a can be formed. In addition, even if the cutting speed is increased (that is, the cutting speed when the cutting blade enters the laminated body), the above-mentioned protected area 100a can be formed in the same manner. If the in-plane tension imparted to the laminate is increased, the above-mentioned protective region 100a can be formed. If it is desired to increase the in-plane tension, it is sufficient to increase the pressure to clamp the laminate during cutting, for example.

The adhesive layer 31 is used as an adhesive layer for bonding the optical laminated film 20 to an image display element such as a liquid crystal cell, an organic EL display element, or other optical members, for example. The adhesive layer-attached optical laminate film 100 may have a release film that can be releasably attached to the surface of the adhesive layer 31 on the side opposite to the optical laminate film 20 side.

The optical laminate film 20 may contain another layer different from the polarizer layer 21, and examples of the other layer include a protective layer, a liquid crystal curing layer, a retardation layer, and a bonding layer. The optical laminated film 20 may have a protective layer on the side opposite to the adhesive layer 31 side when viewed from the polarizer layer 21, and the protective layer may include a hard coat layer constituting the surface on the side opposite to the polarizer layer 21 side.

<First implementation type>

FIG. 4 is a schematic cross-sectional view schematically showing the adhesive layer-attached optical laminate film of the first embodiment. As shown in Figure 4, the adhesive layer-attached optical laminate film 130 has an optical laminate film 20 and an adhesive layer 31 in this order. The adhesive layer 31 has a peelable surface on the opposite side of the optical laminate film 20 side. Bonded separation membrane 32.

The optical laminated film 20 has a surface protective film 24, a first protective layer 22, a polarizer layer 21, and a second protective layer 23 in this order. The first protective layer 22 includes a hard coat layer constituting a surface on the side opposite to the adhesive layer 31 side, and a surface protective film 24 is releasably attached to the hard coat layer surface.

In the optical laminated film 130 with an adhesive layer, the side area 130a shown in FIG. 4 is a protection area. In the protection area 130a, the adhesive layer 31 is positioned at the outermost position than the polarizer layer 21 It protrudes further outside and is raised toward the polarizer layer 21 side.

<Second Implementation Type>

Fig. 5 is a schematic cross-sectional view schematically showing an adhesive layer-attached optical laminate film of the second embodiment. As shown in Figure 5, the adhesive layer-attached optical laminate film 140 has an optical laminate film 20 and an adhesive layer 31 in this order. The adhesive layer 31 has a peelable surface on the opposite side of the optical laminate film 20. Bonded separation membrane 32.

The optical laminated film 20 has a surface protective film 24, a first protective layer 22, a polarizer layer 21, a second protective layer 23, a first bonding layer 25, a first liquid crystal hardening layer 26, a second bonding layer 27, And the second liquid crystal hardened layer 28. The first protective layer 22 includes a hard coat layer constituting a surface on the side opposite to the adhesive layer 31 side, and a surface protective film 24 is releasably bonded to the hard coat layer surface.

In the optical laminated film 140 with an adhesive layer, the side area 140a shown in FIG. 5 is a protection area. In the protection area 140a, the adhesive layer 31 protrudes to the outside than the outermost position of the polarizer layer 21 and is tilted toward the polarizer layer 21 side.

In the protective region 140a of the optical laminate film 140 with the adhesive layer, the other layers other than the adhesive layer 31 may also protrude outward from the outermost position of the polarizer layer 21 in the same way as the adhesive layer 31. The shape is tilted toward the side of the polarizer layer 21. Figure 5 shows the following situation: In the protected area 140a, in addition to the adhesive layer 31, the first bonding layer 25, the first liquid crystal hardening layer 26, and the second liquid crystal hardening layer 28 are also the same as the adhesive layer 31 The ground has a shape that protrudes to the outside than the outermost position of the polarizer layer 21 and is tilted toward the polarizer layer 21 side. As for the side surface of the cutting surface, in the layer where the inclination of the pushing force measured by the test method of the following examples is 50g/mm or less, the condition when the cutting blade enters is similar to that of the adhesive layer 31, so it can be It is estimated that, like the adhesive layer 31, it is easy to have a shape that protrudes to the outside than the outermost end position of the polarizer layer 21 and warps toward the polarizer layer 21 side.

The optical laminate film with an adhesive layer of the present invention may have a layer with an inclination of 50 g/mm or less of pushing force.

Hereinafter, the materials of each layer of the optical laminated film forming the adhesive layer will be described in detail.

(Optical Laminated Film 20)

The optical laminated film 20 has a polarizer layer 21. The thickness of the optical laminate film 20 is usually 5 μm or more and 200 μm or less, may be 150 μm or less, or may be 120 μm or less.

(Polarizer layer 21)

The polarizer layer 21 includes, for example, a stretched film or stretched layer to which a dye having absorption anisotropy is adsorbed, a layer obtained by coating and curing a dye having an absorption anisotropy, and the like. Examples of pigments having absorption anisotropy include dichroic pigments. Regarding the dichroic dye, specifically, iodine or a dichroic organic dye is used. Dichroic organic dyes include: dichroic direct dyes including C.I.DIRECTRED 39 and other bisazo compounds, and dichroic direct dyes including compounds such as trisazo and tetrasazo.

The thickness of the polarizer layer 21 is, for example, 2 μm or more and 40 μm or less. The thickness of the polarizer layer is 5 μm or more, and may be 20 μm or less, preferably 15 μm or less, and more preferably 10 μm or less.

(1) Polarizer layer as a stretched film or stretched layer

A polarizer layer that is cured by coating a pigment with anisotropy of absorption, for example: a composition containing a liquid crystalline dichroic pigment or a composition containing a dichroic pigment and a polymerizable liquid crystal A polarizer layer containing a cured product of a polymerizable liquid crystal compound, such as a layer obtained by curing. Compared with the stretched film or stretched layer on which the pigment with absorption anisotropy is adsorbed, the polarizer layer that is coated with the pigment with absorption anisotropy and hardened has no limitation in the bending direction, so it is better.

As the polarizer layer of "extended film with absorption anisotropic pigment", It can often be manufactured through the following steps: the step of uniaxially extending the polyvinyl alcohol resin film; the step of adsorbing the dichroic pigment by dyeing the polyvinyl alcohol resin film with the dichroic pigment; The step of treating the polyvinyl alcohol resin film of the color pigment with an aqueous solution of boric acid; and the step of washing with water after being treated with the aqueous solution of boric acid.

The polyvinyl alcohol resin is obtained by saponifying a polyvinyl acetate resin. For polyvinyl acetate-based resins, in addition to polyvinyl acetate, which is a homopolymer of vinyl acetate, copolymers of vinyl acetate and other monomers copolymerizable therewith can also be used. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth)acrylamides having an ammonium group.

The degree of saponification of the polyvinyl alcohol-based resin is generally about 85 mol% or more and 100 mol% or less, preferably 98 mol% or more. The polyvinyl alcohol resin may be modified, for example, polyvinyl formal or polyvinyl acetal modified by aldehydes may also be used. The degree of polymerization of the polyvinyl alcohol resin is usually 1,000 or more and 10,000 or less, preferably 1,500 or more and 5,000 or less.

The polarizer layer as the "extended layer adsorbed with anisotropic pigments" can usually be manufactured through the following steps: a step of coating a coating liquid containing the above-mentioned polyvinyl alcohol-based resin on a substrate film; The step of uniaxially stretching the film; the step of dyeing the polyvinyl alcohol resin layer of the uniaxially stretched laminated film with a dichroic pigment to absorb the dichroic pigment and forming a polarizer layer; The step of treating the color pigment film with an aqueous solution of boric acid; and the step of washing with water after being treated with the aqueous solution of boric acid. If necessary, the base film can be peeled and removed from the polarizer layer. The material of the base film can be, for example, the same material as the base film of the surface protection film 24 described later.

(2) A polarizer layer that is coated with anisotropic absorption pigment and hardened

Regarding the polarizer layer formed by coating and curing a pigment with anisotropic absorption, a composition containing a polymerizable dichroic pigment with liquid crystallinity or a composition containing a dichroic pigment and a polymerizable liquid crystal can be mentioned A polarizer layer containing a cured product of a polymerizable liquid crystal compound, such as a layer obtained by coating and curing a base film. If necessary, the base film can be peeled and removed from the polarizer layer. The material of the base film can be, for example, the same material as the base film of the surface protection film 24 described later.

(The first protective layer 22, the second protective layer 23)

The optical laminated film 20 may include the first protective layer 22 laminated on the surface of the polarizer layer 21 on the side opposite to the adhesive layer 31, and may also include the first protective layer 22 laminated on the surface of the polarizer layer 21 on the adhesive layer 31 side. The second protection layer 23. The first protective layer 22 and the second protective layer 23 can be made of optically transparent thermoplastic resins, such as chain polyolefin resins (polypropylene resins, etc.), cyclic polyolefin resins (norbornene resins, etc.) ) And other polyolefin resins; cellulose resins such as cellulose triacetate and cellulose diacetate; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polycarbonate resins ; (Meth)acrylic resins such as methyl methacrylate resins; polystyrene resins; polyvinyl chloride resins; acrylonitrile/butadiene/styrene resins; acrylonitrile/styrene resins; poly Vinyl acetate-based resin; polyvinylidene chloride-based resin; polyamide-based resin; polyacetal-based resin; modified polyphenylene ether-based resin; polyether-based resin; polyether-based resin; polyarylate-based resin ; Polyimide-based resin; Polyimide-based resin; Coating or film composed of a mixture of one or more of these. The thickness of the protective layer is usually 1 μm or more and 100 μm or less, preferably 5 μm or more and 80 μm or less, more preferably 60 μm or less, and still more preferably 50 μm or less.

The protective film system can be bonded to the polarizer layer 21 via an adhesive layer, for example. Examples of the adhesive forming the adhesive layer include water-based adhesives, active energy ray-curable adhesives, or thermosetting adhesives, and water-based adhesives and active energy ray-curable adhesives are preferably used.

The two opposing surfaces bonded via the adhesive layer may be subjected to corona treatment, plasma treatment, flame treatment, etc. in advance, and may have a primer layer or the like.

The first protective layer 22 and the second protective layer 23 may be protective layers made of the same material, or may be protective layers made of different materials. The first protective layer 22 may be provided with an optical function layer such as an anti-glare layer, a light diffusion layer, a retardation layer, and an anti-reflection layer, or a surface treatment layer such as a hard coat layer, an antistatic layer, and an antifouling layer on its surface. When the first protective layer 22 has a hard coat layer, cracks are likely to occur, but according to the present invention, even with such a configuration, cracks can be suppressed.

(Surface protection film 24)

The optical laminated film 20 may have a surface protection film 24 constituting a surface on the side opposite to the surface of the adhesive layer 31. For example, after the optical laminated film with the adhesive layer is attached to the image display element or other optical components, the surface protective film 24 will be peeled off together with the adhesive layer it has.

The surface protection film 24 has a base film and an adhesive layer. The thickness of the surface protection film 24 is, for example, 15 μm or more and 100 μm or less, preferably 20 μm or more and 80 μm or less, and more preferably 30 μm or more and 60 μm or less.

The resin that forms the base film includes, for example, chain polyolefin resins such as polyethylene and polypropylene; cyclic polyolefin resins such as norbornene resins; polyethylene terephthalate or polyethylene naphthalate Polyester resins such as ethylene glycol; polycarbonate resins; thermoplastic resins such as a mixture of one or more of these. The base material layer may have a single-layer structure or a multilayer structure, but it is preferably a single-layer structure from the viewpoints of ease of manufacture and manufacturing cost. The substrate layer may be a uniaxially stretched film or a biaxially stretched film, but from the viewpoints of the mechanical strength of the film, the ease of manufacture, and the manufacturing cost, it is preferably a biaxially stretched film.

The adhesive layer can be composed of an adhesive composition mainly composed of (meth)acrylic, rubber, urethane, ester, silicone, polyvinyl ether, etc. resins. . Among them, an adhesive composition using (meth)acrylic resin excellent in transparency, weather resistance, heat resistance, etc., as a base polymer is preferred. The adhesive composition can be an active energy ray hardening type or a heat hardening type.

(The first liquid crystal hardened layer 26, the second liquid crystal hardened layer 28)

The optical laminate film 20 may include one layer or two or more layers of a liquid crystal cured layer composed of a polymer cured product of a polymerizable liquid crystal compound. The optical laminated film 140 with a bonding layer of the second embodiment has a first liquid crystal hardened layer 26 and a second liquid crystal hardened layer 28 as liquid crystal hardened layers. Examples of the liquid crystal cured layer include those that function as a retardation layer. The liquid crystal hardened layer can be formed by applying a composition containing a polymerizable liquid crystal compound to a base film and curing it. An alignment layer can be formed between the base film and the coating layer. The liquid crystal hardening layer may be incorporated into the optical laminated film 20 in the form of an alignment layer and/or a base film.

The liquid crystal hardening layer can be formed using a known polymerizable liquid crystal compound. The type of liquid crystal compound is not particularly limited, and rod-shaped liquid crystal compounds, disc-shaped liquid crystal compounds, and mixtures thereof can be used. Examples of polymerizable liquid crystal compounds include Japanese Patent Application Publication No. 11-513019, Japanese Patent Application Publication No. 2005-289980, Japanese Patent Application Publication No. 2007-108732, Japanese Patent Application Publication No. 2010-244038, Japanese Patent Application Publication No. 2010-31223 Bulletin No. 2010-270108, JP 2011-6360, JP 2011-207765, JP 2016-81035, International Publication No. 2017/043438, and JP The polymerizable liquid crystal compound described in the publication No. 2011-207765.

For example, by coating a composition containing a polymerizable liquid crystal compound on the alignment layer to form a coating film, and curing the coating film, a liquid crystal cured layer can be formed. The thickness of the liquid crystal hardened layer is preferably 0.5 μm to 10 μm, more preferably 0.5 μm to 5 μm.

Regarding the composition containing the polymerizable liquid crystal compound, in addition to the polymerizable liquid crystal compound, it may also contain a polymerization initiator, a polymerizable monomer, a surfactant, a solvent, an adhesion modifier, Plasticizer, aligning agent, etc. Examples of the coating method of the composition containing the polymerizable liquid crystal compound include known methods such as die coating method. The curing method of the composition containing the polymerizable liquid crystal compound includes known methods such as irradiation with active energy rays (for example, ultraviolet rays).

(The first bonding layer 25, the second bonding layer 27)

The optical laminated film 20 may contain a bonding layer for bonding two layers. The optical laminated film 140 with a bonding layer of the second embodiment has a first bonding layer 25 and a second bonding layer 27 as bonding layers. Examples of the bonding layer include an adhesive layer and an adhesive layer. For the adhesive layer, a water-based adhesive, an active energy ray-curable adhesive, or a thermosetting adhesive is used. The adhesive layer is also applicable to the description of the adhesive layer provided on the surface protective film 24 described above.

For the two opposing surfaces to be bonded through the bonding layer, corona treatment, plasma treatment, flame treatment, etc. may be performed in advance, and a primer layer may also be provided.

(Retardation layer)

The optical laminated film 20 may have one or more retardation layers. The retardation layer may be the above-mentioned liquid crystal cured layer or resin film. Examples of the retardation layer include a positive A plate such as a λ/4 plate or a λ/2 plate, and a positive C plate.

<Adhesive Layer 31>

The adhesive layer 31 can be constituted by using an adhesive composition mainly composed of (meth)acrylic, rubber, urethane, ester, silicone, polyvinyl ether, etc. resins. Among them, an adhesive composition using (meth)acrylic resin excellent in transparency, weather resistance, heat resistance, etc., as a base polymer is preferred. The adhesive composition can be an active energy ray hardening type or a heat hardening type.

The (meth)acrylic resin (base polymer) used in the adhesive composition is suitable for use, for example, butyl (meth)acrylate, ethyl (meth)acrylate, isooctyl (meth)acrylate, (Meth) 2-ethylhexyl acrylate and other (meth) acrylate and other (meth) acrylate polymers or copolymers as monomers Things. Among the base polymers, it is preferable to copolymerize a polar monomer. Examples of polar monomers include (meth)acrylic acid, 2-hydroxypropyl (meth)acrylate, hydroxyethyl (meth)acrylate, (meth)acrylamide, (meth)acrylic acid N, N-di A monomer having a carboxyl group, a hydroxyl group, an amide group, an amino group, an epoxy group, etc., such as methylamino ethyl and glycidyl (meth)acrylate.

The adhesive composition may contain only the above-mentioned base polymer, but usually contains a crosslinking agent. The cross-linking agent may include, for example: metal ions with more than 2 valence, which will form metal carboxylic acid salts with carboxyl groups; polyamine compounds, which will form amide bonds with carboxyl groups; polyepoxy compounds or polyols, Those that form an ester bond with the carboxyl group; and those that form an amide bond between the polyisocyanate compound and the carboxyl group. Among them, polyisocyanate compounds are preferred.

The so-called active energy ray curable adhesive composition has the following properties: it hardens by being irradiated with active energy rays such as ultraviolet rays or electron rays; and has adhesiveness and can adhere to the film before the active energy rays are irradiated When the body is attached, it will be cured by the active energy rays, and the properties of the adhesion can be adjusted. The active energy ray curable adhesive composition is preferably an ultraviolet curable adhesive composition. The active energy ray curable adhesive composition may further contain an active energy ray polymerizable compound in addition to the base polymer and the crosslinking agent. Furthermore, if necessary, a photopolymerization initiator, photosensitizer, etc. may be contained.

The adhesive composition may contain fine particles, beads (resin beads, glass beads, etc.), glass fibers, resins other than the base polymer, adhesiveness imparting agents, fillers (metal powder or other inorganic powders) to impart light scattering properties Etc.), antioxidants, ultraviolet absorbers, dyes, pigments, colorants, defoamers, anti-corrosion agents, photopolymerization initiators and other additives.

Regarding the formation of the adhesive layer 31 on the optical laminated film 20, for example, the following two methods can be performed: the adhesive composition is dissolved or dispersed in an organic solvent such as toluene or ethyl acetate to prepare an adhesive liquid, and A method of directly coating the object surface of the polarizing plate to form the adhesive layer 31; or A method in which the adhesive layer 31 is first formed into a sheet shape on the release film subjected to the mold release treatment, and the adhesive layer 31 is moved and adhered to the target surface of the optical laminated film 20. The adhesive layer 31 can be formed by coating the organic solvent dilution of the adhesive composition on the substrate and drying. When an active energy ray-curable adhesive composition is used, the formed adhesive layer 31 can be irradiated with active energy rays to form a cured product having a desired degree of curing.

The thickness of the adhesive layer 31 is determined in accordance with its adhesive strength, etc., but it is more suitably in the range of 1 μm or more and 50 μm or less, and preferably 2 μm or more and 40 μm or less.

The storage elastic modulus of the adhesive layer 31 measured at a temperature of 20° C. and an angular frequency of 100 radians/sec is usually 1 MPa or less, preferably 0.15 MPa or less. The storage elastic modulus of the adhesive is usually 0.001 MPa or more, preferably 0.01 MPa or more.

<Separation Membrane 32>

The optical laminated film with the adhesive layer may include a separation film 32 provided on the surface of the adhesive layer 31. The separation membrane 32 may be a film composed of polyethylene resin such as polyethylene, polypropylene resin such as polypropylene, polyester resin such as polyethylene terephthalate, or the like. Among them, a stretched film of polyethylene terephthalate is preferred. The separation film 32 is peeled, and the optical laminated film 20 is bonded to the object via the adhesive layer 31.

[Method for manufacturing optical laminated film with adhesive layer]

The method for manufacturing an optical laminated film with an adhesive layer of the present invention has the following steps: a step of preparing a raw material laminated film, the raw material laminated film having an optical laminated film, an adhesive layer, and a separation film in this order, the aforementioned optical laminated film A polarizer layer 21 containing a dichroic pigment adsorbed and aligned, the separation film is releasably attached to the adhesive layer; and a cutting step is to insert an etching knife into the raw laminate film from the separation film side and cut the raw laminate The film forms the side surface. The adhesive layer-attached optical laminate film obtained by such a manufacturing method may be, for example, the above-mentioned adhesive layer-attached optical laminate film having a protective area on the side surface.

FIG. 6 is a plan view showing an example of an etching die equipped with an etching knife used in the dicing step in the manufacturing method of the adhesive layer-attached optical laminate film 120 shown in FIG. 3. The etching knife mold 121 is formed by etching a metal plate into a three-dimensionally protruding shape. The outline 122 shown in FIG. 6 represents the edge of the etching knife, which is connected to the optical laminate film 120 with the adhesive layer. The outline is consistent.

The etching knife mold 121 is crimped to the raw material laminated film, and the etching knife 122 is inserted into the raw material laminated film and cut, thereby forming the side surface and simultaneously punching the optical laminated film 120 with the adhesive layer. As the raw material laminated film for punching, multiple sheets can be laminated. In the case of one sheet, the dimensional accuracy of the obtained polarizing plate is better, so it is preferable. According to the etching knife 121, 6 optical laminated films with adhesive layers can be produced at the same time for each raw laminated film by one punching. The sides of the optical laminated film 120 with adhesive layer produced in this way are all cut surfaces.

The etching knife 121 is produced by patterning the resist film by laser irradiation and etching. Therefore, a die with high dimensional accuracy is obtained. On the other hand, because it is produced by etching, the tip of the knife is relatively unsharp. The etching knife is also called the spire knife. In contrast, the Thomson blade has a sharper tip because it is made by mechanical grinding. The reason why an adhesive layer-attached optical laminate film with a protective area on the side surface can be obtained by the manufacturing method of the present invention is presumed as follows: since the cutting is performed using a sharp knife, which is an etching knife, it is sharper than using a knife tip In the case of the Thomson knife, it is easier to apply force to the layer direction of the adhesive layer 31, thereby forming a protrusion on the adhesive layer 31, and by making the spire knife enter from the side of the separation membrane 32 to protrude The part tends to tilt toward the polarizer layer 21 side.

FIG. 7 is a cross-sectional view of the etching blade 122. FIG. The etching knife 122 is composed of a knife tip 122a and a body 122b. The angle β of the blade edge 122a is preferably 20° to 40°, more preferably 25° to 35°. The thickness t of the main body 122b is preferably 0.1 mm to 1 mm, more preferably 0.2 mm to 0.6 mm.

FIG. 8 is a cross-sectional view schematically showing the cutting step using the etching knife 122. As shown in FIG. 8, the raw material laminated film 150 is placed on the support plate 160. At this time, one sheet of the raw material laminated film 150 is placed so that the optical laminated film 20 of the raw material laminated film 150 is positioned on the support plate 160 side and the separation film 32 side is positioned away from the supporting plate 160 side. The raw material laminated film 150 is laminated and placed in plural pieces, and plural pieces can be punched at the same time. Then, the etching knife 122 is inserted into the raw material build-up film 150 from the side of the separation film 32. After the etching blade 122 reaches the support plate 160, the etching blade 122 is pulled out of the raw material laminated film 150, and the punching is finished.

9 to 11 are cross-sectional views schematically showing an example of the cross-sectional shape of the etching blade 122, respectively. As shown in Fig. 9, the etching knife 122 can be a double-edged blade, which after cutting is used as the purpose of the adhesive layer on the side of the optical laminate film (hereinafter referred to as "A side") and its opposite side (hereinafter referred to as “B side”) are all inclined with respect to the vertical line (entry direction). As shown in FIG. 10, the etching knife 122 may be a single-edged blade, wherein the A surface is parallel to the vertical line (entry direction), and only the B surface is inclined to the vertical line (entry direction). As shown in FIG. 11, the etching knife 122 can also be a double-edged blade, wherein the inclination angle of the A surface relative to the vertical line (entry direction) is different from the inclination angle of the B surface relative to the vertical line (entry direction).

The angle α1 of the surface A of the etching knife 122 with respect to the vertical direction (entry direction) is preferably 0° to 20°. The angle α2 of the surface B of the etching knife 122 with respect to the vertical direction (entry direction) is preferably 14° to 20°. The sum of two angles (α1+α2) is preferably 20° or more from the viewpoint of sufficient strength of the cutting blade, and preferably 40° or less from the viewpoint of facilitating cutting. The two angles (α1, α2) can be the same (α1=α2). At this time, the etching knife 122 is a double-edged blade as shown in FIG. 9. The two angles (α1, α2) can also be different. At this time, the etching knife 122 may be a single edge with an angle α1 of 0° as shown in FIG. 10, a double edge with α1<α2 as shown in FIG. 11, or a double edge with α1>α2. Usually when the two angles (α1, α2) are different, α1<α2.

From the viewpoint that the distance d can be increased, the angle α1 is preferably larger. On the other hand, with From the viewpoint of reducing damage (damage, etc.) to the optical laminate film to which the adhesive layer is attached due to the penetration of the etching knife during cutting, the angle α1 is preferably smaller.

When punching, the etching knife 122 is inserted from the side of the separation film 32 to form a side surface with a protected area. In addition, the distance between the outermost position of the adhesive layer 31 and the outermost position of the polarizer layer 21 can be adjusted by adjusting the shape of the etching knife 122, the speed at which the etching knife 122 enters the material laminated film 150, etc. Distance d. The larger the angle (α1+α2) of the front end of the etching knife 122 and the more blunt the front end, the distance d can be increased.

The material of the support plate 160 is not particularly limited. For example, a support plate made of polypropylene can be used.

In the manufacturing method of the adhesive layer-attached optical laminate film 110 shown in FIG. 2, punching of the outer frame and punching of the through hole 51 can be performed at the same time, or can be performed at different timings. From the viewpoint of improving the position accuracy of the punching, it is preferable to perform them simultaneously.

In the manufacturing method of the adhesive layer-attached optical laminate film, in the cutting step, it is preferable to form the side surface by punching with an etching knife. In addition, it is also possible to combine, for example, a method of cutting using a router and using a drill. Rotating cutting tools for piercing processing methods, etc.

[Image display device]

The optical laminated film with adhesive layer can be used in image display devices. Examples of image display elements used in image display devices include liquid crystal display elements and organic EL display elements. When constructing the liquid crystal display device, the optical laminated film with the adhesive layer can be used by being arranged on the visual confirmation side, can be arranged on the backlight side, and can also be used by both the visual confirmation side and the backlight side.

(Example)

The following examples illustrate the present invention in further detail, but the present invention is not limited to these examples. The "%" and "parts" in the examples are mass% and mass parts unless otherwise specified. Test and The measurement system was performed in the following manner.

[Optical Laminated Film A with Adhesive Layer] (Example)

<Production steps of raw material laminated film>

The optical laminate film 130 with the adhesive layer of the first embodiment shown in Fig. 4 is made in the following way. The "surface protective film 24/first protective layer 22/polarizer layer 21/second The protective layer 23/adhesive layer 31/separation film 32" is a raw material laminated film.

(Production of polarizer layer 21)

After dyeing the long polyvinyl alcohol film in an aqueous solution containing iodine, it is uniaxially stretched 6 times in the longitudinal direction between rollers with different speed ratios in the aqueous solution containing boric acid to obtain an absorption axis in the longitudinal direction. The long strip of polarizer layer. The elongated polarizer layer is wound after being stretched to form a winding body. The visual sensitivity correction polarization degree of the polarizer layer is about 99.995%, the visual sensitivity correction monomer transmittance is 42.7%, and the thickness is 12μm.

(Preparation for the first protective layer 22)

As the first protective layer 22, a long strip of cellulose triacetate film with a hard coat layer (thickness 32 μm, made by Toppan Printing Co., Ltd., trade name: 25KCHCN-TC) was prepared.

(Preparation for the second protective layer 23)

A long strip of cyclic polyolefin resin film (thickness 13 μm, ZEONOR FILM manufactured by Japan's ZEON Corporation, trade name: ZF14-013) was prepared as the second protective layer 23.

(Layering step)

After cutting the polarizer layer 21, the first protective layer 22, and the second protective layer 23 prepared or prepared in the above manner into 300mm×400mm, respectively, the first layer 21 is bonded to both sides of the polarizer layer 21 through a polyvinyl alcohol-based adhesive. The first protective layer 22 and the second protective layer 23 are placed in a drying oven at 80°C for 3 minutes. Secondly, for the first 2. After corona treatment is performed on the surface of the protective layer 23, the acrylic adhesive layer 31 (thickness 20 μm) to which the separation film 32 is bonded is laminated on the corona treatment surface side. Finally, on the surface of the first protective layer 22, a release film with a micro-adhesive as the surface protective film 24 is laminated to obtain a raw material laminated film. The corona treatment is performed using a corona discharge device manufactured by Kasuga Electric Co., Ltd. Specifically, the corona surface treatment frame "STR-1764", the high-frequency power supply "CT-0212", and the high-voltage transformer "CT-T02W" are used. In this raw material laminated film, a polyvinyl alcohol-based adhesive layer (thickness 0.2μm or less) is interposed between the polarizer layer 21 and the first protective layer 22, and is interposed between the polarizer layer 21 and the second protective layer 23 A polyvinyl alcohol-based adhesive layer (thickness 0.2 μm or less) is placed.

<cutting step>

One piece of the obtained raw material laminated film (300mm×400mm) was punched into the shape of the optical laminated film with adhesive layer shown in Figure 3 using the etching knife shown in Figure 8 to obtain the optical layer with adhesive layer Laminated film A. The etching knife is a double-edged etching knife shown in Figure 9 with α1=α2=15°. At the time of punching shown in Figure 8, the surface protection film 24 of the raw material laminated film is positioned on the support plate 160 side and the separation film 32 is positioned away from the supporting plate 160 side to place the raw material laminated film 150 and shield The four corners of the tape are fixed to the support plate 160, respectively, so that the etching knife enters the raw laminate film from the side of the separation film 32. The punching is performed so that the absorption axis of the polarizer layer 21 is parallel to the longitudinal direction of the optical laminate film A with the adhesive layer. In addition, the cutting knife is used for those who can move back and forth in the punching direction with a stroke of 24mm (sufficiently exceeding the thickness of the laminated film of the raw material) (as "1 stroke"), 1.5 seconds in 1 stroke, and fold back and forth movement Point cut the raw material laminated film 150. The support plate 160 is formed by stacking one acrylic sheet (thickness 3.5 mm) and one polypropylene sheet (thickness 1.0 mm). The support plate 160 is used in such a way that the polypropylene sheet side is in contact with the raw material laminated film 150.

[Optical Laminated Film B with Adhesive Layer] (Comparative Example)

<Production steps of raw material laminated film>

According to the same method as the production step in the optical laminated film A with adhesive layer, the raw material laminated film is produced.

<cutting step>

One piece of the obtained raw material laminated film (300mm×400mm) was punched into the shape of the optical laminated film with adhesive layer shown in Figure 3 using the etching knife shown in Figure 8 to obtain the optical layer with adhesive layer Laminated film B. At the time of punching as shown in Figure 8, the separation film 32 of the raw material laminated film is positioned on the support plate 160 side and the surface protection film 24 is positioned away from the supporting plate 160 side to place the raw material laminated film 150 to mask the tape The four corners are fixed to the support plate 160, respectively, so that the etching knife enters the raw laminate film from the surface protection film 24 side. Punching is performed so that the absorption axis of the polarizer layer 21 is parallel to the longitudinal direction (length 400 mm) of the optical laminate film B of the adhesive layer. In addition, the cutting knife is used for those who can move back and forth in the punching direction with a stroke of 24mm (sufficiently exceeding the thickness of the laminated film of the raw material) (as "1 stroke"), 1.5 seconds in 1 stroke, and fold back and forth movement Point cut the raw material laminated film 150. The support plate 160 is formed by stacking one acrylic sheet (thickness 3.5 mm) and one polypropylene sheet (thickness 1.0 mm). The support plate 160 is used in such a way that the polypropylene sheet side is in contact with the raw material laminated film 150.

[Optical Laminated Film C with Adhesive Layer] (Example)

<Production steps of raw material laminated film>

The adhesive layer-attached optical laminate film 14 of the second embodiment shown in Fig. 5 is produced in the following way. The "surface protective film 24/first protective layer 22/polarizer layer 21/second The protective layer 23/first bonding layer 25/first liquid crystal cured layer 26/second bonding layer 27/second liquid crystal cured layer 28/adhesive layer 31/separation film 32" is a raw material laminated film.

(Production of polarizer layer 21)

After dyeing the long polyvinyl alcohol film in an aqueous solution containing iodine, it is uniaxially stretched 6 times in the aqueous solution containing boric acid between rollers with different speed ratios to obtain a long strip with an absorption axis in the length direction. Shaped polarizer layer. The elongated polarizer layer is wound after being stretched to form a winding body. The visual sensitivity correction polarization degree of the polarizer layer is about 99.995%, the visual sensitivity correction monomer transmittance is 42.7%, and the thickness is 12μm.

(Preparation for the first protective layer 22)

As the first protective layer 22, a long strip of cellulose triacetate film with a hard coat layer (thickness 32 μm, made by Toppan Printing Co., Ltd., trade name: 25KCHCN-TC) was prepared.

(Preparation for the second protective layer 23)

As the second protective layer 23, a long strip of cellulose triacetate film (thickness 40 μm, trade name made by KONICA MINOLTA: KC4UYW) was prepared.

(Preparation of the first liquid crystal hardened layer 26)

As the first liquid crystal cured layer 26, a film (thickness of 1 μm) composed of a layer formed by curing a nematic liquid crystal compound and an alignment film was prepared. The in-plane retardation value of the first liquid crystal cured layer 26 is 140 nm, Re(450)/Re(550) is less than 1.0, and Re(650)/Re(550) is more than 1.0. With respect to the first liquid crystal cured layer 26, the pushing force measured using the method of measuring the pushing force described later was 8.8 g/mm.

(Preparation of the second liquid crystal hardened layer 28)

As the second liquid crystal cured layer 28, a film (thickness 2 μm) composed of a layer cured with a rod-shaped liquid crystal compound and an alignment film was prepared. In the second liquid crystal hardened layer 28, the in-plane relationship of Nz>Nx=Ny is satisfied, the in-plane retardation value Re(550) is 0.6 nm, and the thickness direction retardation value Rth(550) is -69.6 nm. With respect to the second liquid crystal cured layer 28, the pushing force measured by the method of measuring the pushing force described later was 38.1 g/mm.

(Layering step)

The polarizer layer 21, the first protective layer 22, the second protective layer 23, the first liquid crystal hardened layer 26, and the second liquid crystal hardened layer 28 prepared or prepared in the above manner were cut into 300mm×400mm, and then passed through polyethylene The first protective layer 22 and the second protective layer 23 were attached to both sides of the polarizer layer 21 with an alcohol-based adhesive, and placed in a drying oven at 80°C for 3 minutes. Next, after corona treatment is performed on the side surface of the second protective layer 23, an acrylic adhesive (thickness 5 μm) is laminated on the corona treatment surface as the first bonding layer 25. The laminated system thus obtained is called the first laminated body. The corona treatment is performed using a corona discharge device manufactured by Kasuga Electric Co., Ltd. Specifically, the corona surface treatment frame "STR-1764", the high-frequency power supply "CT-0212", and the high-voltage transformer "CT-T02W" are used.

Then, an ultraviolet curable adhesive is applied to the surface of the first liquid crystal hardened layer 26, and the second liquid crystal hardened layer 28 is bonded, and an ultraviolet irradiation device [manufactured by Fusion UV Systems Co., Ltd.] is used from the second liquid crystal hardened layer 28 side to accumulate The amount of light is 400mJ/cm ² (UV-B) to irradiate ultraviolet rays to harden the adhesive. The thus obtained laminated system constituted by the laminated structure of "the first liquid crystal hardened layer 26/the second bonding layer 27 constituted by the adhesive layer/the second liquid crystal hardened layer 28" is called the second laminated body.

The first laminated body and the second laminated body obtained in the above manner are laminated so that the first bonding layer 25 of the first laminated body and the first liquid crystal cured layer 26 of the second laminated body are bonded together. At this time, the layering is performed so that the slow axis of the first liquid crystal hardened layer 26 becomes an angle of -45° with respect to the absorption axis of the polarizer layer 21.

After that, on the surface of the second liquid crystal cured layer 28, the acrylic adhesive layer 31 (thickness 20 μm) to which the separation film 32 was bonded was laminated. Finally, on the surface of the first protective layer 22, a release film with a micro-adhesive as the surface protective film 24 is laminated to obtain a raw material laminated film.

<cutting step>

Cut 1 piece of the obtained raw material laminated film (300mm×400mm) with the etching knife shown in Figure 8 into The shape of the optical laminated film with adhesive layer shown in Fig. 3, and the optical laminated film C with adhesive layer is obtained. In the punching shown in Figure 8, the raw material laminated film surface protection film 24 is positioned on the support plate 160 side and the separation film 32 is positioned away from the support plate 160 side to place the raw material laminated film 150, so that the masking tape will The four corners are respectively fixed to the support plate 160 so that the etching knife enters the raw material laminated film from the side of the separation film 32. The punching is performed so that the absorption axis (extension direction) of the polarizer layer 21 is parallel to the length direction (400 mm) of the optical laminate film C with the adhesive layer. In addition, the cutting knife uses a stroke (hereinafter referred to as "1 stroke") with a stroke of 24mm (which fully exceeds the thickness of the raw material laminated film) in the punching direction for back-and-forth movement. It takes 1.5 seconds to go back and forth in one stroke and move back and forth. The raw material laminated film 150 is cut at the turning point. The support plate 160 is formed by stacking one acrylic sheet (thickness 3.5 mm) and one polypropylene sheet (thickness 1.0 mm). The support plate 160 is used in such a way that the polypropylene sheet side is in contact with the raw material laminated film 150.

[Optical Laminated Film D with Adhesive Layer] (Comparative Example)

<Production steps of raw material laminated film>

The raw material laminated film is produced according to the same method as the production process of the adhesive layer-attached optical laminated film D.

<Punching Step>

One sheet of the obtained raw material laminated film (300mm×400mm) was punched into the shape of the optical laminated film with the adhesive layer shown in Fig. 3 using the etching knife shown in Fig. 8 to obtain sample 4. At the time of punching as shown in Figure 8, the separation film 32 of the raw material laminated film is positioned on the support plate 160 side and the surface protection film 24 is positioned away from the supporting plate 160 side to place the raw material laminated film 150 to mask the tape The four corners are fixed to the support plate 160, respectively, so that the etching knife enters the raw laminate film from the surface protection film 24 side. Punching is to make the absorption axis of the polarizer layer 21 parallel to the length direction (400mm) of the optical laminate film D with the adhesive layer The way to proceed. In addition, the cutting knife uses a stroke (hereinafter referred to as "1 stroke") with a stroke of 24mm (which fully exceeds the thickness of the raw material laminated film) in the punching direction for back-and-forth movement. It takes 1.5 seconds to go back and forth in one stroke and move back and forth. The raw material laminated film 150 is cut at the turning point. The support plate 160 is formed by stacking one acrylic sheet (thickness 3.5 mm) and one polypropylene sheet (thickness 1.0 mm). The support plate 160 is used in such a way that the polypropylene sheet side is in contact with the raw material laminated film 150.

[Side view]

For optical laminated films A to D with adhesive layers, observe the cross-sectional shape of the starting position of the curved area on the side surface with an optical microscope. (A) and (b) of Figure 12 schematically show the observation images of the adhesive layer-attached optical laminated films A and B with an optical microscope. Fig. 13 (a) and (b) schematically show the observation images of the adhesive layer-attached optical laminate film C and D with an optical microscope.

It can be seen from Figures 12 and 13, that in the side surfaces of the optical laminate films A and C to which the adhesive layer is attached, the adhesive layer 31 protrudes to the outside than the outermost position of the polarizer layer 21 and toward the polarizer layer 21 Side cocked. That is, a protected area is formed. On the other hand, in the side surfaces of the optical laminate films B and D with the adhesive layer, although the adhesive layer 31 protrudes to the outside than the outermost position of the polarizer layer 21, it is raised to the side opposite to the polarizer layer 21 . That is, there is no protected area. In addition, in the optical laminated film A with adhesive layer to the optical laminated film D with adhesive layer, the distance d between the outermost position of the adhesive layer 31 and the outermost position of the polarizer layer 21 is 15 μm. In addition, in the optical laminate film A with adhesive layer ~ the optical laminate film D with adhesive layer, no polyvinyl alcohol-based adhesive layer interposed between the polarizer layer 21 and the first protective layer 22 was observed , And a polyvinyl alcohol adhesive layer interposed between the polarizer layer 21 and the second protective layer 23. Neither the adhesive layer-attached optical laminate film C nor the adhesive layer-attached optical laminate film D can be identified and observed respectively. The first bonding layer 25, the first liquid crystal hardened layer 26, the second bonding layer 27 and the second In the liquid crystal hardening layer 28, only a whole layer (denoted as layer 29 in Fig. 13 (a) and (b)) is observed.

[Thermal shock test]

Laminate the optical laminate films A to D with the adhesive layer on the surface of an alkali-free glass (EAGLE XG made by Corning, 120×200×0.7mm) cleaned with ethanol, and then heat it at 50°C, 0.5MPa (table (Pressure) autoclave treatment for 20 minutes. This was used as a sample for evaluation.

The sample for evaluation was put into the thermal shock test tank, and the sample was subjected to thermal stimulation at -40°C and 85°C in a cycle of 30 minutes each. The heat stimulation from low temperature to high temperature was used as one cycle, and a total of 100 cycles were tested on each sample.

[Rupture Evaluation]

Observe the occurrence of cracks in the evaluation sample after the thermal shock test with an optical microscope. Especially for the detailed observation of the curved area. Fig. 14 shows an optical microscope image of an example of the fracture. This image (optical microscope image) is an optical microscope image observed from the upper surface of the common specific area of the optical laminated film A and B with the adhesive layer. For each sample for evaluation, the cracks generated from the curved surface area specified in the same range were observed, and the cracks were classified according to the crack length as follows, and the number of cracks included in each classification was measured. The results are shown in Table 1.

Short rupture: rupture less than 100μm in length

Medium rupture: rupture with a length of more than 100μm and less than 200μm

Long rupture: rupture with a length of more than 200μm

[Table 1]

As shown in Table 1, the adhesive layer-attached optical laminate films A and C of the present invention did not crack even after being subjected to 100 cycles in the thermal shock test.

[Determination of Pushing Force]

Prepare a cellulose triacetate film with a thickness of 60 μm as sample A, a cellulose triacetate film with a thickness of 20 μm as sample B, and a cycloolefin polymer film with a thickness of 23 μm as sample C. As samples D and E, the adhesive The first liquid crystal hardened layer 26 and the second liquid crystal hardened layer 28 prepared for the optical laminated films C and D of the agent layer were measured for the pushing force of each sample using the following method.

As shown in the top view of (a) and the cross-sectional view of (b) in Figure 15, each sample 170 is cut into a rectangular shape of 30 mm × 30 mm, and a table paper 171 (thickness 85 μm) with a rectangular opening 171a of 10 mm × 10 mm in the center , 30mm×30mm rectangle), the adhesive layer 172 with a thickness of 25μm is pasted so as to plug the opening 171a. Thereafter, from the side of the sample 170 of the plugged opening 171a Above, an iron rod 173 with a tip diameter of 1.0 mm was pushed in at a speed of 0.33 mm/s, and the pushing force with respect to the amount of deformation in the thickness direction was measured using a portable compression tester (KEN-G5, manufactured by KATO TECH Co., Ltd.). Figure 16 shows the measurement results. Table 2 shows the tilt of the pushing force calculated based on the measurement result of Figure 16.

[Table 2]

20: Optical laminated film

20a: surface

21: Polarizer layer

31: Adhesive layer

100: Optical laminated film with adhesive layer

100a: Protected area

d: distance

Claims (10)

An optical laminate film with an adhesive layer, which has an optical laminate film and an adhesive layer in sequence, Wherein, the aforementioned optical multilayer film includes a polarizer layer with dichroic pigments adsorbed and aligned, At least a part of the side surface of the optical laminated film with the adhesive layer is a protection area, In the protection area, the adhesive layer protrudes to the outside than the outermost position of the polarizer layer, and is raised toward the polarizer layer side. The optical laminated film with adhesive layer as described in item 1 of the scope of patent application, wherein: At least a part of the side surface of the optical laminated film with the adhesive layer is a curved area, In the curved area, the contour of the surface of the optical laminated film on the side opposite to the adhesive layer side is curved, At least a part of the aforementioned curved area is the aforementioned protected area. The optical laminated film with adhesive layer as described in item 2 of the scope of patent application, wherein: The protected area in the curved area includes: the angle θ formed by the contour and the absorption axis direction of the polarizer layer continuously changes, and the angle θ exceeds 0° and is less than 90°. The adhesive layer-attached optical laminate film described in any one of items 1 to 3 of the scope of patent application, wherein the aforementioned protective area is a cut surface. The adhesive layer-attached optical laminate film described in any one of the scope of the patent application described in any one of items 1 to 4, wherein the protection area includes the position between the outermost position of the adhesive layer and the outermost position of the polarizer layer The area where the distance d is 10μm or more. The optical laminate film with an adhesive layer as described in any one of items 1 to 5 of the scope of patent application, wherein the adhesive layer on the opposite side of the optical laminate film side further has: peelable Separation membrane attached to the ground. The optical laminated film with an adhesive layer as described in any one of items 1 to 6 of the scope of the patent application, wherein the optical laminated film has a liquid crystal hardening layer, and the liquid crystal hardening layer is cured by polymerization of a polymerizable liquid crystal compound Constituted by things. The adhesive layer-attached optical laminate film described in any one of items 1 to 7 of the scope of patent application, wherein: The optical laminated film has a protective layer on the side opposite to the adhesive layer when viewed from the polarizer layer, The protective layer has a hard coat layer, and the hard coat layer forms a surface on the side opposite to the polarizer layer side. A manufacturing method of optical laminated film with adhesive layer has the following steps: The step of preparing a raw material laminated film, the raw material laminated film has an optical laminated film, an adhesive layer, and a separation film in sequence. The optical laminated film includes a polarizer layer with a dichroic pigment adsorbed and aligned, and the separation film is peelable Bonded to the aforementioned adhesive layer; and In the cutting step, an etching knife is introduced from the side of the separation membrane with respect to the raw material laminated film to cut the raw material laminated film to form a side surface. The method for manufacturing an optical laminated film with an adhesive layer as described in the scope of the patent application, wherein at least a part of the side surface is a protected area, and in the protected area, the adhesive layer is higher than the polarizer layer. The outermost position protrudes further to the outside and is raised toward the polarizer layer side.

Images