TW202000823A - Single-side-protected polarization film with adhesive layer, image display device, and continuous production method therefor - Google Patents

Abstract

The objective of the present invention is to provide a single-side-protected polarization film with an adhesive layer wherein the film has excellent initial rework ability, durability and electric conduction stability under a high-temperature and/or high-humidity environment and is also not readily released from a glass substrate, or the like, even when exposed to an environment in which dew condensation arises. This single-side-protected polarization film with an adhesive layer comprises: a single-side-protected polarization film having a protective film only on one surface of a polarizer; and an adhesive layer, directly or via a coating layer, on the polarizer side of the single-side-protected polarization film. The adhesive layer contains a (meth)acrylic polymer as a base polymer, has a weight change rate of 1.1% or greater, an adhesive force P0 of 10 N/25 mm or less prior to immersion in water, and an adhesive force P1 of 1.6 N/25 mm or more after immersion for two hours in water.

Description

Single-sided protective polarizing film with adhesive layer, image display device and continuous manufacturing method thereof

The invention relates to a single-sided protective polarizing film with an adhesive layer, which has a single-sided protective polarizing film provided with a protective film on only one side of a polarizer and an adhesive layer. The single-sided protective polarizing film with an adhesive layer can form an image display device such as a liquid crystal display device (LCD) or an organic EL display device alone or in the form of a laminated optical film.

Background of the invention In the liquid crystal display device, it is necessary and indispensable to dispose polarizing films on both sides of the glass substrate forming the surface of the liquid crystal panel according to its image forming method. The polarizing film is generally used when a polarizing member composed of a polyvinyl alcohol-based film and a dichroic material such as iodine passes through a polyvinyl alcohol-based adhesive or the like and has a protective film laminated on one or both sides.

When attaching the polarizing film to a liquid crystal cell or the like, an adhesive is usually used. In addition, the adhesive is provided on one side of the polarizing film in the form of an adhesive layer in advance, because it has the advantages of instantly fixing the polarizing film and fixing the polarizing film without a drying step. That is, a polarizing film with an adhesive layer is used for attaching the polarizing film.

In addition, the polarizing film or the polarizing film with an adhesive layer is subject to shrinkage stress of the polarizing member under the severe environment of thermal shock (such as repeated thermal shock test at -30℃ and 80℃ or high temperature test at 100℃) The change causes a problem that the polarizing member easily generates cracks (through cracks) in the direction of the absorption axis as a whole. That is, the polarizing film or the polarizing film with an adhesive layer is not sufficiently durable against thermal shock under the aforementioned severe environment. In particular, from the viewpoint of thinning, the single-sided protective polarizing film with an adhesive layer and a single-sided protective polarizing film provided with a protective film on only one side of the polarizer is insufficient in durability against the aforementioned thermal shock. Moreover, penetrating cracks due to the aforementioned thermal shock are likely to occur when the size of the polarizing film is increased.

For example, in order to impart high durability in high-temperature environments, it is proposed in the literature to use a storage elastic modulus at 23° C. of 0.2 to 10 MPa and a thickness of 2 μm or more and less than 25 μm as a single-sided protection with an adhesive layer Adhesive layer of polarizing film (Patent Document 1). In addition, in order to impart good durability in high-temperature environments, a literature proposes a polarizing plate which is provided with a pressure-sensitive adhesive layer on one side of the polarizer and a transparent resin film on the other side of the polarizer The protective layer is constituted, and the polarizing plate uses the one that exhibits a storage elastic modulus of 0.15 to 1 MPa in a temperature range of 23 to 80° C. as the aforementioned pressure-sensitive adhesive layer (Patent Document 2). In addition, in order to suppress the occurrence of the above-mentioned penetrating cracks, there are literatures suggesting that the shrinkage force in the direction perpendicular to the absorption axis of the polarizer is controlled to be small, and the storage elastic modulus of the adhesive layer at 23° C. is 0.20 MPa or more , As an adhesive layer for protecting the polarizing film on one side with an adhesive layer (Patent Document 3). In addition, there are also thinner polarizers. For example, there is a document that proposes a thin polarizer whose optical characteristics of single transmittance and polarization degree are controlled and which shows high directivity (Patent Document 4).

However, even though Patent Document 1 has satisfactory durability, the thickness of the polarizer is as large as 25 μm, so it is impossible to prevent penetrating cracks caused by shrinkage stress of the polarizer. In addition, since Patent Documents 1 to 3 are aimed at improving the durability of a single-sided protective polarizing film with an adhesive layer, there are many boric acids used in polarizers. It is known that when the polarizer contains more boric acid than a certain value, the crosslinking of boric acid is promoted during heating and the shrinkage stress of the polarizer is increased, so it is not ideal from the viewpoint of suppressing the occurrence of penetrating cracks. In other words, although the storage elastic modulus of the adhesive layer can be suppressed to some extent in Patent Documents 1 to 3, it cannot be said that it can sufficiently suppress the occurrence of penetration cracks.

In addition, the polarizer is also thinned. When the polarizer used to protect the polarizing film on one side with the adhesive layer is thinned, the shrinkage stress variation of the polarizer will also be reduced. Therefore, it is known that the thinning polarizer can suppress the occurrence of the aforementioned penetrating cracks.

However, it is known that, with regard to the single-sided protective polarizing film with an adhesive layer that suppresses the occurrence of the aforementioned penetrating cracks, when the optical characteristics are controlled as described in Patent Document 4 and the polarizer is thinned (for example, the thickness is set at 12μm or less), when a single-sided protective polarizing film with an adhesive layer is loaded with mechanical impact (including the case where the deflection load is applied to the polarizer side), a very thin part of the polarizer absorption axis direction Slit (hereinafter also referred to as nano slit). It is also known that the generation of the aforementioned nano slits is independent of the size of the polarizing film. It is also known that the aforementioned nano slit does not occur when a double-sided protective polarizing film having protective films on both sides of the polarizer is used. It is also known that when a penetrating crack is generated on the polarizer, the stress around the penetrating crack will be released, so the penetrating crack will not be generated adjacently, but the nano slits will also be generated adjacently, in addition to being generated independently. It is also known that penetrating cracks have ductility extending in the direction of the absorption axis of the polarizing member where cracks have been generated, while nano slits do not have the aforementioned ductility. In this way, it can be seen that the aforementioned nano slit is a new problem that occurs when the single-sided protective polarizing film that has suppressed the occurrence of penetrating cracks is a thinning polarizer and the optical characteristics are controlled within a predetermined range. Zhou Zhizhi said that the aforementioned penetrating cracks are completely different phenomena derived from the problem.

In addition, because the aforementioned nano slit is extremely thin, it cannot be detected in a general environment. Therefore, assuming that even if a nano slit is formed on the polarizer, it is difficult to confirm the defect only by protecting the light transmission of the polarizing film on one side with the adhesive layer. That is, the single-sided protective polarizing film is usually made into a long film shape and then the defect is detected by automatic optical inspection, but it is difficult to detect the nano slit as a defect in this defect detection. It is known that the defects caused by the aforementioned nano slits are caused by the width of the nano slits when the single-sided protective polarizing film with an adhesive layer is attached to the glass substrate of the image display panel, etc. and placed in a heated environment. The direction is expanded and detected (for example, the presence or absence of light transmission).

Therefore, in the case of using a single-sided protective polarizing film with an adhesive layer on a thin polarizer, not only the penetrating cracks, but also hope to suppress the defects caused by the nano slits. In addition, the single-sided protective polarizing film with an adhesive layer is thinner than the polarizing film composed of double-sided protective films with protective films on both sides, so it is easy to bend or break the polarizing film during handling.

In order to suppress the defects caused by the aforementioned nano slits, some documents propose a technique of providing a transparent layer (coating layer) between the polarizer that protects the polarizing film on one side with the adhesive layer and the adhesive layer (Patent Document 5 ). By providing a transparent layer, the polarizing film becomes less likely to bend when external stress is applied to the polarizing film, so that the generation of nano slits can be suppressed.

In addition, when manufacturing a liquid crystal display device, when the single-sided protective polarizing film with an adhesive layer is attached to the liquid crystal cell, the release film is peeled off from the adhesive layer of the single-sided protective polarizing film with an adhesive layer The release film generates static electricity. The static electricity generated in this way affects the orientation of the liquid crystal in the liquid crystal display device, resulting in defects. Moreover, when the liquid crystal display device is used, display unevenness caused by static electricity may sometimes occur. The generation of static electricity can be suppressed by, for example, forming an antistatic layer on the outer surface of the polarizing film, but the effect is small and there is a problem that the generation of static electricity cannot be prevented at all. Therefore, in order to suppress the generation of static electricity from the fundamental position, it is required to impart an antistatic function to the adhesive layer. As a means for imparting an antistatic function to the adhesive layer, for example, it has been proposed to mix an ionic compound in the adhesive used to form the adhesive layer (Patent Documents 6 to 8). In detail, Patent Document 6 has proposed an adhesive composition for an optical film blended with an alkali metal salt and/or an organic cation-anion salt. In Patent Document 7, an adhesive composition containing an onium-anion salt and an alkali metal salt has been proposed as a raw material for an adhesive layer of a polarizing film with an adhesive layer. In Patent Document 8, an adhesive composition containing an alkali metal salt has been proposed as a raw material for the adhesive layer of an adhesive polarizing plate.

In addition, the adhesive layer of the single-sided protective polarizing film with an adhesive layer is required to have high durability. For example, it is required to be used in a durability test using heating and humidification, which is usually carried out as an environmental promotion test. Defects such as peeling and embossing of the adhesive layer may occur.

A variety of adhesive compositions for optical applications have been studied, for example, there have been proposals in the literature for an adhesive composition that does not cause peeling even when it is placed under high humidity and heat conditions after the optical film is attached Or foaming (Patent Document 9).

Advanced technical literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2010-44211 Patent Document 2: Japanese Patent Laid-Open No. 2008-197309 Patent Document 3: Japanese Patent Application Publication No. 2013-72951 Patent Literature 4: Specification of Japanese Patent No. 4551481 Patent Literature 5: Specification of Japanese Patent No. 6077618 Patent Literature 6: Japanese Patent Laid-Open No. 2015-199942 Patent Document 7: Japanese Patent Laid-Open No. 2014-48497 Patent Document 8: Japanese Patent Laid-Open No. 2012-247574 Patent Document 9: Japanese Patent Laid-Open No. 2009-242767

Summary of the invention Problems to be solved by invention However, when a conventional glass substrate with a polarizing film made by attaching a single-sided protective polarizing film with an adhesive layer to a glass substrate forming the surface of a liquid crystal panel is exposed to condensation, it may be easy The problem of peeling occurs at the interface between the glass substrate and the adhesive layer.

In addition, when forming a single-sided protective polarizing film with an adhesive layer attached to a glass substrate or the like on the surface of the liquid crystal panel, if foreign substances or bubbles are mixed and the bonding error occurs, the polarizing film must be peeled off from the glass substrate or the like . A single-sided protective polarizing film with an adhesive layer of a thin polarizer is used. Since the polarizer is very thin and the protective film is only provided on one side of the polarizer, the overall thickness is quite thin. Therefore, the single-sided protective polarizing film with the adhesive layer of the conventional thin polarizer has a problem that it is easily broken when peeled off from the glass substrate or the like. Therefore, the adhesive layer also requires reworkability that does not cause defects when the polarizing film is peeled off from a glass substrate or the like.

The object of the present invention is to provide a single-sided protective polarizing film with an adhesive layer, which has excellent initial reworkability, durability under high temperature and/or high humidity environment, and conductive stability, and condensation occurs even when exposed to Under the environment, it is still not easy to peel off from the glass substrate. Moreover, in addition to the aforementioned effects, the object of the present invention is to provide a single-sided protective polarizer with an adhesive layer that can suppress defects caused by the nano slit even if a coating layer is not provided between the polarizer and the adhesive layer film.

Furthermore, an object of the present invention is to provide an image display device having the single-sided protective polarizing film with the adhesive layer and a continuous manufacturing method thereof.

Means to solve the problem The inventors of the present case have found through intensive studies that the above-mentioned problems can be solved by using a single-sided protective polarizing film with an adhesive layer described below, and the present invention has been achieved.

That is, the present invention relates to a single-sided protective polarizing film with an adhesive layer, which is characterized in that: it has: a single-sided protective polarizing film, which only has a protective film on one side of the polarizer; and, as mentioned above The polarizer side of the single-sided protective polarizing film has an adhesive layer directly or has an adhesive layer across the coating layer; the adhesive layer contains a (meth)acrylic polymer as a base polymer, and the adhesive layer has the following formula (1) The calculated weight change rate is 1.1% or more, and the adhesive force P ₀ of the adhesive layer under the following conditions is 10 N/25 mm or less, and the adhesive force P ₁ under the following conditions is 1.6 N/25 mm or more; Weight change rate (%) = {(W ₁ -W ₀ )/W ₀ }×100 (1) W ₀ = weight of the adhesive layer after drying the aforementioned adhesive layer at 23° C. for 2 hours W ₁ = will the adhesive layer after the aforementioned drying for 5 hours at 55% RH 23 ℃, and placing the weight layer of the adhesive after the 5 hours at 95% RH 60 ℃ adhesion P _0: single the attachment adhesive layers The adhesive layer of the surface-protecting polarizing film is attached to the surface of the alkali-free glass and subjected to an autoclave treatment at 50°C and 0.5atm for 15 minutes at a peeling temperature of 23°C, a peeling speed of 300mm/min and a peeling angle of 90 Under the conditions, the adhesive force when the adhesive layer is peeled from the surface of the alkali-free glass; Adhesion P ₁ : the adhesive layer of the single-sided protective polarizing film with the adhesive layer is attached to the surface of the alkali-free glass, Then, autoclave treatment was carried out at 50°C and 0.5 atm for 15 minutes to obtain a laminate. The laminate was immersed in 23°C water for 2 hours. After removing the laminate from the water, the peeling temperature was 23°C. Adhesion when peeling the adhesive layer from the surface of the alkali-free glass under the conditions of a peeling speed of 300 mm/min and a peeling angle of 90 degrees.

In order to impart durability and conductive stability to the adhesive layer provided on the polarizer side of the single-sided protective polarizing film, it is preferable to introduce polarity into the (meth)acrylic polymer, which is the base polymer of the adhesive layer, by copolymerization monomer. However, the hydrophilicity of the (meth)acrylic polymer into which the polar monomer has been introduced by copolymerization becomes high. Therefore, the adhesive layer containing the (meth)acrylic polymer easily absorbs water when exposed to an environment where condensation occurs, and the adhesive force is easily reduced, so that it easily peels off from the glass substrate or the like. The present inventors have conducted active research on the relationship between the physical properties of the adhesive layer provided on the polarizer side of the single-sided protective polarizing film, the initial reworkability, and the situation of peeling from the glass substrate, etc., and found that by applying the adhesive The weight change rate of the layer before and after humidification and the adhesion under specific conditions are adjusted to a specific range, and a single-sided protective polarizing film with an adhesive layer can be prepared, which can be used in the initial reworkability, high temperature and / Or while maintaining high durability and conductivity stability in a high humidity environment, it is not easy to peel off from glass substrates even when exposed to an environment where condensation will occur.

The aforementioned (meth)acrylic polymer preferably contains the following as monomer units: 50% by weight or more of alkyl (meth)acrylate (A), and its homopolymer has a glass transition temperature of less than 0°C; and 0.1 to 20% by weight of high Tg monomer (B), which is selected from the group consisting of (meth)acrylic acid alkyl ester (b1) and (meth)acryl-containing monomer (b2) At least one of the above, the glass transition temperature of the homopolymer of the (meth)acrylic acid alkyl ester (b1) is 0° C. or higher, and the glass of the homopolymer containing the (meth)acryloyl monomer (b2) The transition temperature is 0°C or higher and has a heterocyclic ring.

Furthermore, the (meth)acrylic polymer preferably contains a polar monomer other than the (meth)acryl-containing monomer (b2) as a monomer unit, and the polar monomer system is selected from nitrogen-containing monomers At least one of the group consisting of monomer, carboxyl group-containing monomer, hydroxyl group-containing monomer and aromatic group-containing monomer.

The aforementioned nitrogen-containing monomer is preferably a vinyl-based monomer having an internal amide ring. In addition, the vinyl monomer having an internal amide ring is preferably a vinylpyrrolidone monomer. In addition, the vinylpyrrolidone-based monomer is preferably N-vinylpyrrolidone.

In addition, the (meth)acrylic polymer preferably contains 0.1 to 5% by weight of the nitrogen-containing monomer as a monomer unit, preferably contains 0.01 to 3% by weight of the carboxyl group-containing monomer, and preferably contains 0.01 to 1 The aforementioned hydroxyl group-containing monomers by weight, and preferably 1 to 20% by weight of the aforementioned aromatic group-containing monomers.

In addition, the weight average molecular weight of the (meth)acrylic polymer is preferably 1.5 million or less.

The adhesive layer preferably contains a silane coupling agent, and the silane coupling agent has at least one functional group selected from the group consisting of epoxy groups, isocyanate groups, mercapto groups, acid anhydride groups, and amine groups. The content of the silane coupling agent is preferably 0.01 to 3 parts by weight relative to 100 parts by weight of the (meth)acrylic polymer.

The thickness of the polarizer is preferably 12 μm or less.

In addition, the polarizer preferably contains a polyvinyl alcohol-based resin, and the optical characteristics represented by the monomer transmittance T and the polarization degree P preferably satisfy the following condition: P>-(10 ^0.929T-42.4 -1) ×100 (only, T<42.3), or P≧99.9 (only, T≧42.3).

In addition, the polarizer preferably contains boric acid at 25% by weight or less based on the total amount of polarizers.

Separator can be provided on the adhesive layer that protects the polarizing film on one side of the adhesive layer. The single-sided protective polarizing film with an adhesive layer provided with a separating member can be used as a rolled body.

Furthermore, the present invention relates to an image display device having the single-sided protective polarizing film with the adhesive layer.

In addition, the present invention relates to a continuous manufacturing method of an image display device, which includes the steps of: releasing the wound adhesive body which is released from the single-sided protective polarizing film of the adhesive layer and conveyed by the separating member The single-sided protective polarizing film of the adhesive layer is continuously attached to the surface of the image display panel through the adhesive layer.

Invention effect The single-sided protective polarizing film with an adhesive layer of the present invention has excellent initial reworkability, so even if a thin polarizer is used, the polarizing film can be peeled from a glass substrate or the like without breaking. In addition, the single-sided protective polarizing film with an adhesive layer of the present invention is excellent in durability under high temperature and/or high humidity environments, so it is less likely to cause defects such as peeling and embossment of the adhesive layer. Moreover, the single-sided protective polarizing film with an adhesive layer of the present invention has excellent conductivity stability under a humidified environment, so the polarizer is not easily deteriorated, and the polarizer is not prone to discoloration. Moreover, even if the single-sided protective polarizing film with an adhesive layer of the present invention is exposed to an environment where condensation will occur, the adhesive force is still not easily reduced, and it is not easy to peel off from the glass substrate or the like. In addition, since the single-sided protective polarizing film with an adhesive layer of the present invention has the adhesive layer, even if no coating layer is provided, the generation of nano slits can be effectively suppressed.

Forms for carrying out the invention The single-sided protective polarizing film with an adhesive layer of the present invention will be described below with reference to FIG. 1. The single-sided protective polarizing film 11 with an adhesive layer of the present invention has, for example, a single-sided protective polarizing film 10 and an adhesive layer 4. The adhesive layer 4 is the adhesive layer of the present invention. As shown in FIG. 1, the single-sided protective polarizing film 10 only has a protective film 2 on one side of the polarizer 1. The polarizer 1 and the protective film 2 are laminated via an adhesive layer 3 (other interlayers such as an adhesive layer and a primer layer). In addition, although not shown, the single-sided protective polarizing film 10 may be provided with an easy adhesion layer on the protection film 2 or may be subjected to an activation process, and the easy adhesion layer and an adhesive may be laminated. Although not shown, a plurality of protective films 2 may be provided. A plurality of protective films 2 may be laminated via an adhesive layer 3 (other intermediary layers such as an adhesive layer and a primer layer).

As shown in FIG. 1 again, the adhesive layer 4 in the single-sided protective polarizing film 11 with an adhesive layer of the present invention may be provided on the polarizer 1 side of the single-sided protective polarizing film 10. Although not shown in the figure, a coating layer may be provided between the polarizer 1 and the adhesive layer 4. The aforementioned coating layer is not particularly limited, and for example, a well-known transparent layer described in Japanese Patent No. 6077618 can be applied. In addition, a separating member 5 may be provided on the adhesive layer 4 of the single-sided protective polarizing film 11 of the present invention with an adhesive layer, and a surface protective film 6 may be provided on the opposite side. The single-sided protective polarizing film 11 with an adhesive layer in FIG. 1 shows the case where both the separating member 5 and the surface protective film 6 are provided. The single-sided protective polarizing film 11 (and the surface protective film 6) having at least the adhesive layer with the separating member 5 can be used in the form of a wound body, for example, it is advantageous to be applied to the release from the wound body as described later The method of attaching the single-sided protective polarizing film 11 with an adhesive layer and conveyed by the separator 5 to the surface of the image display panel through the adhesive layer 4 (hereinafter also referred to as "roll to panel" method), The representative is described in Japanese Patent No. 4404043). The single-sided protective polarizing film with an adhesive layer described in FIG. 1 is suitable for use from the viewpoint of suppressing warpage of the display panel after bonding and suppressing the occurrence of nano slits.

FIG. 2 is a conceptual diagram comparing the nano slit a and the penetrating crack b generated in the polarizer. FIG. 2(A) shows the nano slit a generated in the polarizer 1, and FIG. 2(B) shows the penetrating crack b generated in the polarizer 1. FIG. The nano slit a is generated due to mechanical impact, and the nano slit a partially generated in the direction of the absorption axis of the polarizer 1 cannot be confirmed at the moment of generation, but can be in a hot environment (such as 80°C or 60°C , 90%RH) confirmed by expansion in the width direction. On the other hand, it is generally considered that the nano slit a has no ductility extending in the direction of the absorption axis of the polarizer. In addition, the aforementioned nano slit a is considered to be generated regardless of the size of the polarizing film. Nano slit a will be generated by itself or adjacent to each other. On the other hand, the penetrating crack b is caused by thermal shock (for example, thermal shock test). The penetrating crack has ductility extending in the direction of the absorption axis of the polarizing member that has generated the crack. When the penetrating crack b occurs, the peripheral stress will be released, so the penetrating crack will not be generated adjacently.

>polarizer> In the present invention, the thickness of the polarizer is preferably 12 μm or less, more preferably 10 μm or less, still more preferably 8 μm or less, and even more preferably 7 μm or less, particularly from the viewpoint of thinning and suppression of penetrating cracks. It is 6 μm or less. On the other hand, the thickness of the polarizer is preferably 1 μm or more. Such a thin polarizer has less thickness variation, good visibility, and little dimensional change, so it has excellent durability against thermal shock.

The polarizer is made of polyvinyl alcohol resin. Examples of polarizers include the adsorption of iodine or dichroic dyes by hydrophilic polymer films such as polyvinyl alcohol-based films, partially formalized polyvinyl alcohol-based films, and ethylene-vinyl acetate copolymer-based partially saponified films. Monochromatic substances, polyolefin oriented films such as polyvinyl alcohol dehydration treatment or polyvinyl chloride dehydrochlorination treatment, etc. Among these, a polarizer composed of a polyvinyl alcohol-based film and a dichroic substance such as iodine is suitable.

The polarizer which dyes the polyvinyl alcohol-based film with iodine and is uniaxially stretched can be produced by, for example, immersing polyvinyl alcohol in an aqueous solution of iodine and dyeing it, and stretching it to 3 to 7 times its original length. It may also contain boric acid, zinc sulfate, zinc chloride, etc. as needed, and may also be immersed in an aqueous solution such as potassium iodide. Further, if necessary, the polyvinyl alcohol-based film is immersed in water and washed with water before dyeing. By washing the polyvinyl alcohol-based film with water, the dirt and anti-caking agent on the surface of the polyvinyl alcohol-based film can be washed. In addition, the polyvinyl alcohol-based film swells to prevent uneven staining and other effects. The extension can be carried out after dyeing with iodine, or it can be dyed while being stretched, or it can be dyed with iodine after being stretched. It can also be extended in an aqueous solution such as boric acid or potassium iodide or in a water bath.

From the viewpoint of elongation stability or optical durability, the polarizer preferably contains boric acid. Moreover, from the viewpoint of suppressing the occurrence of penetrating cracks and nano slits and suppressing expansion, the content of boric acid contained in the polarizer is preferably 25% by weight or less relative to the total amount of polarizers, further preferably 20% by weight or less, further It is preferably 18% by weight or less, more preferably 16% by weight or less. When the content of boric acid contained in the polarizer is greater than 25% by weight, even if the thickness of the polarizer is thinned (for example, a thickness of 12 μm or less), the shrinkage stress of the polarizer will still be high and easily cause penetrating cracks, which is undesirable. On the other hand, from the viewpoint of the extension stability and optical durability of the polarizer, the boric acid content is preferably 10% by weight or more, and more preferably 12% by weight or more with respect to the total amount of the polarizer.

Typical examples of thin polarizers are: Specification of Japanese Patent No. 4751486, Specification of Japanese Patent No. 4751481, Specification of Japanese Patent No. 4815544, Specification of Japanese Patent No. 5048120, Specification of Japanese Patent No. 5587517, Manual of International Publication No. 2014/077599, The thin polarizer described in International Publication No. 2014/077636 manual, etc., or the thin polarizer produced by the manufacturing method described in the same.

The aforementioned polarizer is preferably configured such that the optical characteristics represented by the single transmittance T and the degree of polarization P satisfy the conditions of the following formula: P>-(10 ^0.929T-42.4 -1)×100 (however, T>42.3), Or P≧99.9 (However, T≧42.3). In short, the polarizer configured to satisfy the aforementioned conditions has the performance required for a liquid crystal television display using a large display element. Specifically, the contrast ratio is 1000:1 or more and the maximum brightness is 500 cd/m ² or more. For other uses, it can be attached to the viewing side of an organic EL display device, for example.

On the other hand, the polarizer configured to satisfy the aforementioned conditions exhibits a high degree of orientation due to the polymer (for example, polyvinyl alcohol-based molecules), so it is compatible with the case of a thin type (such as a thickness of 12 μm or less). The tensile breaking stress in the direction perpendicular to the absorption axis direction becomes significantly smaller. As a result, for example, when subjected to a mechanical impact greater than the tensile breaking stress during the manufacturing process of the polarizing film, the nano slits are likely to be generated in the direction of the absorption axis of the polarizer. Therefore, the present invention is particularly suitable for using the single-sided protective polarizing film with the polarizer (or using the single-sided protective polarizing film with its adhesive layer).

In the manufacturing method including the step of extending in the state of a laminate and the dyeing step, from the viewpoint of extending at a high magnification and improving the polarizing performance, the thin polarizer is described in Japanese Patent No. 4751486, Japanese Patent No. 4751481 The specification described in the Japanese Patent No. 4815544 and the Japanese Patent No. 4815544 are preferably prepared by a method including a step of extending in an aqueous solution of boric acid, and are particularly as described in Japanese Patent No. 4751481 and Japanese Patent No. 4815544 Preferably, it is prepared by a method including a step of auxiliary air stretching before stretching in a boric acid aqueous solution. These thin polarizers can be obtained by a manufacturing method including the following steps: a step of extending a polyvinyl alcohol-based resin (hereinafter, also referred to as PVA-based resin) layer and a resin substrate for extension in the state of a laminate and Dyeing steps. According to this manufacturing method, even if the PVA-based resin layer is very thin, it is supported by the resin substrate for stretching, so it can be stretched without breaking or other defects caused by stretching.

>Protection film> The material constituting the protective film is preferably excellent in transparency, mechanical strength, thermal stability, moisture blocking property, isotropy and the like. Examples include polyester-based polymers such as polyethylene terephthalate or polyethylene naphthalate; cellulose-based polymers such as diethyl cellulose or triethyl cellulose; polymethacrylate Acrylic polymers such as esters; styrene polymers such as polystyrene and acrylonitrile-styrene copolymers (AS resins); polycarbonate polymers and the like. In addition, the following polymers can be cited as examples of the polymer forming the above protective film: polyethylene, polypropylene, polyolefin having a ring system or a norbornene structure, such as an ethylene-propylene copolymer polyolefin polymer , Vinyl chloride polymer, nylon or aromatic polyamide amide polymer, amide imide polymer, lanyard polymer, polyether lanyard polymer, polyether ether ketone polymer, polyextrusion Phenylsulfide-based polymer, vinyl alcohol-based polymer, chlorinated vinylidene-based polymer, vinyl butyral-based polymer, aryl ester-based polymer, polyoxymethylene-based polymer, epoxy-based polymer or the above-mentioned polymer Of blends, etc.

In addition, the protective film may contain at least one kind of any appropriate additives. Additives include, for example, ultraviolet absorbers, antioxidants, slip agents, plasticizers, mold release agents, colorants, flame retardants, nucleating agents, antistatic agents, pigments, colorants, and the like. The content of the thermoplastic resin in the protective film is preferably 50 to 100% by weight, preferably 50 to 99% by weight, more preferably 60 to 98% by weight, and particularly preferably 70 to 97% by weight. In the protective film, when the content of the thermoplastic resin is 50% by weight or less, there is a possibility that the high transparency and the like originally possessed by the thermoplastic resin may not be sufficiently exhibited.

As the protective film, a phase difference film, a brightness enhancement film, a diffusion film, etc. can also be used. Examples of the retardation film include those having a frontal phase difference of 40 nm or more and/or a thickness direction phase difference of 80 nm or more. The frontal phase difference is usually controlled in the range of 40~200nm, and the thickness direction phase difference is usually controlled in the range of 80~300nm. When a retardation film is used as a protective film, the retardation film can also function as a polarizer protective film, so it can be made thinner.

Examples of the retardation film include a birefringent film obtained by uniaxially or biaxially stretching a thermoplastic resin film. The stretching temperature, stretching magnification, etc. can be appropriately set according to the phase difference value, film material and thickness.

The thickness of the protective film can be appropriately determined, but it is generally about 1 to 500 μm from the viewpoints of workability, thinness, etc. such as strength and operability. In particular, it is preferably 1 to 300 μm, preferably 5 to 200 μm, more preferably 5 to 150 μm, and particularly preferably 5 to 80 μm thin.

A functional layer such as a hard coat layer, an anti-reflection layer, an anti-adhesion layer, a diffusion layer, and even an anti-glare layer may be provided on the surface of the aforementioned protective film that does not follow the polarizer. In addition, the above-mentioned functional layers such as the hard coat layer, the anti-reflection layer, the anti-adhesive layer, the diffusion layer, or the anti-glare layer can be provided separately from the protective film in addition to the protective film itself.

>Intermediary layer> The protective film and the polarizer are laminated via an intermediary layer such as an adhesive layer, an adhesive layer, a primer layer (primer layer). At this time, it is desired that the two can be stacked without an air gap through the interposer. The protective film and the polarizer are preferably laminated via an adhesive.

The adhesive layer is formed of an adhesive. The type of adhesive is not particularly limited, and various substances can be used. The adhesive layer is not particularly limited as long as it is optically transparent, and various types of substances such as water-based, solvent-based, hot-melt adhesive, and active energy ray hardening types can be used as the adhesive, and water-based adhesives or active energy ray hardening types can be used. Adhesive is appropriate.

Examples of the water-based adhesive include isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex-based adhesives, and water-based polyesters. The water-based adhesive is usually used as an adhesive composed of an aqueous solution, and usually contains 0.5 to 60% by weight of solid content.

The active energy ray-curable adhesive is an adhesive that is cured by active energy rays such as electron beams, ultraviolet rays (radical curing type, cation curing type), etc. For example, it can be used in the form of electron beam curing type or ultraviolet curing type. For the active energy ray hardening type adhesive, for example, a photo radical hardening type adhesive can be used. When the photoradical hardening type active energy ray hardening type adhesive is used as the ultraviolet hardening type, the adhesive contains a radical polymerizable compound and a photopolymerization initiator.

The application method of the adhesive can be appropriately selected according to the viscosity or the target thickness of the adhesive. Examples of coating methods include: reverse coater, gravure coater (direct, reverse or lithography), bar reverse coater, roll coater, die coater, bar coater, bar coater, etc. . In addition, for coating, a method such as a dipping method can be used as appropriate.

In addition, when using an aqueous adhesive or the like for the application of the adhesive, the thickness of the adhesive layer to be finally formed is preferably 30 to 300 nm. The thickness of the aforementioned adhesive layer is more preferably 60 to 250 nm. On the other hand, when an active energy ray-curable adhesive is used, it is preferably performed so that the thickness of the adhesive layer is 0.1 to 200 μm. It is preferably 0.5-50 μm, and more preferably 0.5-10 μm.

As for the lamination of the polarizer and the protective film, an easy adhesion layer may be provided between the protection film and the adhesive layer. The easy-adhesion layer may be formed of various resins having, for example, the following skeletons: polyester skeleton, polyether skeleton, polycarbonate skeleton, polyurethane skeleton, polysiloxane system, polyamide skeleton, polyimide skeleton , Polyvinyl alcohol skeleton, etc. These polymer resins can be used alone or in combination of two or more. In addition, other additives may be added when the easy-adhesion layer is formed. Specifically, stabilizers such as tackifiers, ultraviolet absorbers, antioxidants, heat-resistant stabilizers, and the like can be used.

The easy-adhesive layer is usually provided on the protective film in advance, and the easy-adhesive layer side of the protective film and the polarizer are laminated by an adhesive layer. The formation of the easy-adhesion layer can be carried out by applying a known technique to the formation material of the easy-adhesion layer on the protective film and drying it. The forming material of the easy-adhesion layer is usually adjusted to a solution that has been diluted to an appropriate concentration in consideration of the thickness after drying and the smoothness of the coating. The thickness of the easy-adhesion layer after drying should be 0.01-5 μm, more preferably 0.02-2 μm, and more preferably 0.05-1 μm. In addition, the easy-adhesion layer may be provided in multiple layers. In this case, the total thickness of the easy-adhesion layer should preferably fall within the above range.

The adhesive layer is formed by the adhesive. As the adhesive, various adhesives can be used, and examples include rubber adhesives, acrylic adhesives, polysiloxane adhesives, urethane adhesives, vinyl alkyl ether adhesives, and polyvinylpyrrolidine. Ketone adhesives, polyacrylamide adhesives, cellulose adhesives, etc. The adhesive base polymer can be selected according to the type of the aforementioned adhesive. Among the above-mentioned adhesives, acrylic adhesives are preferably used from the viewpoints of excellent optical transparency, exhibiting appropriate wettability, cohesiveness and adhesive properties of adhesion, and excellent weather resistance and heat resistance.

A primer layer (primer layer) is formed to improve the adhesion between the polarizer and the protective film. The material constituting the primer layer is not particularly limited as long as it can exert a certain degree of strong adhesion to both the base film and the polyvinyl alcohol-based resin layer. For example, a thermoplastic resin excellent in transparency, thermal stability, and extensibility can be used. Examples of the thermoplastic resin include acrylic resins, polyolefin resins, polyester resins, polyvinyl alcohol resins, and mixtures thereof.

>Adhesive layer> The adhesive layer of the single-sided protective polarizing film with an adhesive layer of the present invention is formed of an acrylic adhesive containing a (meth)acrylic polymer as a base polymer. Acrylic adhesives have excellent optical transparency, exhibit moderate wettability, cohesiveness, and adhesive properties of adhesion, and have excellent weather resistance and heat resistance. Therefore, they are suitable as materials for forming adhesive layers.

The weight change rate of the adhesive layer calculated by the following formula (1) is 1.1% or more, and preferably 1.2% or more, more preferably 1.3% or more. If the weight change rate is less than 1.1%, the durability and conductivity stability of the adhesive layer in a high-temperature and/or high-humidity environment will tend to deteriorate. In addition, from the viewpoint of adjusting the following adhesive forces P ₁ and P ₂ to the intended range, the weight change rate is preferably 2.0% or less, and preferably 1.8% or less. Weight change rate (%) = {(W ₁ -W ₀ )/W ₀ }×100 (1) W ₀ = weight of the adhesive layer after drying the aforementioned adhesive layer at 23° C. for 2 hours W ₁ = will The weight of the adhesive layer after drying the adhesive layer at 23°C 55%RH for 5 hours and at 60°C 95%RH for 5 hours

In addition, the adhesive force P ₀ of the adhesive layer under the following conditions is 10 N/25 mm or less, and the adhesive force P ₁ under the following conditions is 1.6 N/25 mm or more. If the aforementioned adhesive force P _{0 is} greater than 10 N/25 mm, the initial reworkability will be deteriorated. From the aforementioned viewpoint, the adhesive force P _{0 is} preferably 8 N/25 mm or less, and preferably 6 N/25 mm or less. In addition, if the aforementioned adhesive force P _{1 is} less than 1.6 N/25 mm, the adhesive force may be easily reduced when exposed to an environment where condensation may occur, and the adhesive layer may easily peel off from the glass substrate or the like. From the aforementioned viewpoint, the aforementioned adhesive force P _{1 is} preferably 2 N/25 mm or more, and more preferably 3 N/25 mm or more. Adhesion P ₀ : The adhesive layer on the single-sided protective polarizing film with the adhesive layer is attached to the surface of alkali-free glass, and subjected to an autoclave treatment at 50°C and 0.5atm for 15 minutes, then at the peeling temperature Adhesion force when peeling the adhesive layer from the surface of the alkali-free glass under the conditions of 23° C., peeling speed 300 mm/min and peeling angle 90 degrees. Adhesive force P ₁ : Protect the polarizing film on the single side with the adhesive layer The adhesive layer is attached to the surface of non-alkali glass and subjected to an autoclave treatment at 50°C and 0.5atm for 15 minutes to obtain a laminate. The laminate is immersed in 23°C water for 2 hours to laminate the aforementioned laminate After the body is taken out of water, the adhesive force when peeling the adhesive layer from the surface of the alkali-free glass under the conditions of peeling temperature 23°C, peeling speed 300 mm/min and peeling angle 90 degrees

In addition, from the aforementioned viewpoint, the adhesive force P ₂ of the adhesive layer under the following conditions is preferably 0.8 N/25 mm or more, and more preferably 1.0 N/25 mm or more. Adhesion P ₂ : The adhesive layer on the single-sided protective polarizing film with the adhesive layer is attached to the surface of the alkali-free glass, and subjected to an autoclave treatment at 50°C and 0.5 atm for 15 minutes to obtain a laminate After immersing the laminate in water at 23°C for 5 hours, after removing the laminate from the water, the adhesive layer was removed from the adhesive layer under the conditions of a peeling temperature of 23°C, a peeling speed of 300 mm/min and a peeling angle of 90 degrees. Adhesion when peeling off alkali-free glass surface

As the (meth)acrylic polymer, those having a monomer unit of an alkyl (meth)acrylate as a main skeleton can be used. In addition, (meth)acrylate refers to acrylate and/or methacrylate, and (meth) in the present invention is also synonymous.

The alkyl (meth)acrylate constituting the main skeleton of the (meth)acrylic polymer has a carbon number of about 1 to 18 in the alkyl group, and specific examples of the alkyl (meth)acrylate can be illustrated as ( Methyl methacrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, Amyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, (meth)acrylic acid Nonyl ester, isononyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, etc., and these can be used alone or in combination.

In order to obtain an adhesive layer having the aforementioned weight change rate and the aforementioned adhesive force P ₀ to P ₂ and suppressing the occurrence of nano slits, the (meth)acrylic polymer preferably contains the following as a monomer unit: 50% by weight The alkyl (meth)acrylate (A) above (more preferably 60% by weight or more, more preferably 70% by weight or more, and even more preferably 80% by weight or more), and the glass transition temperature of its homopolymer Below 0℃ (more preferably below -20℃, more preferably below -40℃); and 0.1~20% by weight (more preferably 1~15% by weight, still more preferably 2.5~10% by weight, then More preferably, it is 4% by weight or more and less than 10% by weight) high Tg monomer (B), which is selected from the group consisting of (meth)acrylic acid alkyl ester (b1) and (meth)acryl-containing monomer (b2) At least one member of the group consisting of the above-mentioned homopolymer of alkyl (meth)acrylate (b1) has a glass transition temperature of 0°C or higher (more preferably 20°C or higher, and still more preferably 40 ℃ or higher), the homopolymer of the (meth)acryloyl group-containing monomer (b2) has a glass transition temperature of 0 ℃ or higher (more preferably 20 ℃ or higher, and more preferably 40 ℃ or higher) and has a heterocyclic ring . Moreover, when the said (meth)acrylic-acid alkylester (b1) and the (meth)acryl-containing monomer (b2) are used together, it will be the total weight %.

Examples of the alkyl (meth)acrylate (A) include ethyl acrylate (Tg: -24°C), n-butyl acrylate (Tg: -50°C), and n-pentyl methacrylate (Tg: -5°C). ), n-hexyl acrylate (Tg: -57°C), n-hexyl methacrylate (Tg: -5°C), n-octyl acrylate (Tg: -65°C), n-octyl methacrylate (Tg: -20°C) ), n-nonyl acrylate (Tg: -58°C), n-lauryl acrylate (Tg: -3°C), n-lauryl methacrylate (Tg: -65°C), n-tetradecyl methacrylate (Tg: -72℃), isopropyl acrylate (Tg: -3℃), isobutyl acrylate (Tg: -40℃), isooctyl acrylate (Tg: -58℃), isooctyl methacrylate (Tg: -45°C), 2-ethylhexyl acrylate (Tg: -70°C), 2-ethylhexyl methacrylate (Tg: -10°C), etc. These can be used alone or in combination. Among these, at least one selected from ethyl acrylate, n-butyl acrylate, n-pentyl methacrylate, n-hexyl acrylate, and 2-ethylhexyl acrylate is preferably used, and n-acrylate is more preferably used Butyl ester. In addition, Tg (glass transition temperature) in each bracket mentioned above is the Tg of the homopolymer obtained by polymerizing each monomer. The following records are also the same.

Examples of the alkyl (meth)acrylate (b1) include methyl acrylate (Tg: 8°C), methyl methacrylate (Tg: 105°C), ethyl methacrylate (Tg: 65°C), acrylic acid N-propyl ester (Tg: 3°C), n-propyl methacrylate (Tg: 35°C), n-pentyl acrylate (Tg: 22°C), n-tetradecyl acrylate (Tg: 24°C), n-sixteen acrylate Ester (Tg: 35°C), n-hexadecyl methacrylate (Tg: 15°C), n-octadecyl acrylate (Tg: 30°C), n-octadecyl methacrylate (Tg: 38°C), etc. (A Group) linear alkyl acrylate; tertiary butyl acrylate (Tg: 43℃), tertiary butyl methacrylate (Tg: 48℃), isopropyl methacrylate (Tg: 81℃) and methyl Isobutyl acrylate (Tg: 48°C) and other branched alkyl (meth)acrylate; cyclohexyl acrylate (Tg: 19°C), cyclohexyl methacrylate (Tg: 65°C), isobornyl acrylate (Tg: 94°C) and isobornyl methacrylate (Tg: 180°C) and other cyclic alkyl (meth)acrylates. These can be used alone or in combination. Among these, at least one kind selected from methyl acrylate, methyl methacrylate, ethyl methacrylate, isobornyl acrylate, and isobornyl methacrylate is preferably used, and it is more preferably selected from At least one of methyl acrylate, methyl methacrylate, and isobornyl acrylate.

環及嗎福林環等脂肪族雜環；吡咯環、咪唑環、吡唑環、

唑環、異

唑環、噻唑環、異噻唑環、吡啶環、嘧啶環、嗒

環及吡

環等芳香族雜環等。前述雜環可與(甲基)丙烯醯基直接鍵結，亦可透過連結基與(甲基)丙烯醯基鍵結。該等之中以脂肪族雜環為宜，更以嗎福林環為宜。前述含(甲基)丙烯醯基單體(b2)可舉例如N-丙烯醯基嗎福林(Tg：145℃)等。該等可單獨使用或可組合使用。在該等之中，尤宜使用N-丙烯醯基嗎福林。The aforementioned (meth)acryloyl group-containing monomer (b2) has a heterocyclic ring. The heterocyclic ring is not particularly limited, but examples thereof include an aziridine ring, an acridine ring, a pyrrolidine ring, a piperidine ring, and a piper

Aliphatic heterocycles such as rings and morpholin rings; pyrrole rings, imidazole rings, pyrazole rings,

Azole ring

Azole ring, thiazole ring, isothiazole ring, pyridine ring, pyrimidine ring, ta

Ring and pyridine

Aromatic heterocycles such as rings. The aforementioned heterocyclic ring may be directly bonded to the (meth)acryloyl group, or may be bonded to the (meth)acryloyl group through a linking group. Among these, aliphatic heterocyclic ring is suitable, and morpholin ring is more suitable. Examples of the (meth)acryloyl group-containing monomer (b2) include N-acryloyl morpholin (Tg: 145°C). These can be used alone or in combination. Among these, N-propenyl morpholin is particularly suitable.

In order to improve adhesiveness, thermal conductivity, etc., one or more kinds of various monomers can be introduced into the (meth)acrylic polymer by copolymerization. Specific examples of the comonomer (except the aforementioned (meth)acryl-containing monomer (b2)) include carboxyl-containing monomers, hydroxyl-containing monomers, nitrogen-containing monomers, and aromatic group-containing monomers. Body etc.

Examples of the carboxyl group-containing monomer include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. These can be used alone or in combination.

Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate. , 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate and (4-hydroxymethylcyclohexyl)-methacrylate, etc. These can be used alone or in combination.

、乙烯基吡

、乙烯基吡咯、乙烯基咪唑、乙烯基

唑、乙烯基嗎福林、N-乙烯基羧酸醯胺類等。該等可單獨使用或可組合使用。Examples of the nitrogen-containing monomer include vinyl monomers having an internal amide ring (for example, vinyl pyrrolidone monomers such as N-vinylpyrrolidone and methylvinylpyrrolidone; and β-internal (Acetylamide ring, delta-lactamide ring, ε-lactamide ring and other vinylimide amide monomers such as vinylamide ring, etc.); maleimide, N-cyclohexylmaleimide, N-phenylmaleimide and other maleimide-based monomers; (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl ( Meth) acrylamide, N-hexyl (meth) acrylamide, N-methyl (meth) acrylamide, N-butyl (meth) acrylamide, N-butyl (meth) (N-substituted) amide monomers such as acrylamide, N-methylol (meth)acrylamide, N-methylolpropane (meth)acrylamide; amine ethyl (meth)acrylate , Aminopropyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, tertiary butylaminoethyl (meth)acrylate, 3-(3-pyridyl)propyl ( (Meth)acrylic acid ester and other (meth)acrylic acid aminoalkyl monomers; N-(meth)acryloyloxymethylene succinimide, N-(meth)acryloyl-6-oxygen Succinimide-based monomers such as hexamethylene succinimide, N-(meth)acryloyl-8-oxyoctamethylene succinimide; cyanide such as acrylonitrile and methacrylonitrile (Meth)acrylate monomers; vinyl pyridine, vinyl piperidone, vinyl pyrimidine, vinyl piper

Vinylpyridine

, Vinylpyrrole, vinylimidazole, vinyl

Azole, vinyl morpholin, N-vinyl carboxylic acid amide, etc. These can be used alone or in combination.

Examples of the aromatic group-containing monomer include benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxyethyl (meth)acrylate. These can be used alone or in combination.

In addition to the above-mentioned monomers, monomers containing an anhydride group such as maleic anhydride and itaconic anhydride; caprolactone adducts of acrylic acid; styrenesulfonic acid or allylsulfonic acid, 2-(methyl )Acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, (meth)acrylic acid sulfopropyl ester or (meth)acryloyloxynaphthalenesulfonic acid containing sulfonic acid group Body; 2-hydroxyethyl propenyl acetyl phosphate and other phosphate-containing monomers and so on. These can be used alone or in combination.

In addition, vinyl monomers such as vinyl acetate, vinyl propionate, styrene, α-methylstyrene, N-vinylcaprolactam, etc.; glycidyl (meth)acrylate, etc. can also be used Epoxy-based acrylic monomer; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxy (meth)acrylate Glycol acrylate monomers such as polypropylene glycol ester; tetrahydrofurfuryl (meth) acrylate, fluoro (meth) acrylate, polysiloxy (meth) acrylate and 2-methoxyethyl acrylate Ester monomers, etc. These can be used alone or in combination.

From the viewpoint of enhancing the cohesive force of the (meth)acrylic polymer to more effectively suppress the generation of the nano slit, it is preferable to select the monomer selected from the group consisting of the carboxyl group-containing monomer, the hydroxyl group-containing monomer, and the nitrogen-containing monomer And at least one polar monomer among the aromatic group-containing monomers (except the aforementioned (meth)acrylic group-containing monomers (b2)) are introduced into the (meth)acrylic polymer by copolymerization It is more preferable to introduce the carboxyl group-containing monomer, the hydroxyl group-containing monomer and the nitrogen-containing monomer into the (meth)acrylic polymer by copolymerization. The aforementioned carboxyl group-containing monomer is preferably (meth)acrylic acid. The aforementioned hydroxyl group-containing monomer is preferably one or more kinds selected from 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate. The nitrogen-containing monomer is preferably a vinyl monomer having an internal amide ring, more preferably the vinyl pyrrolidone monomer, and even more preferably N-vinyl pyrrolidone. By introducing the nitrogen-containing monomer into the (meth)acrylic polymer by copolymerization, the nano slit can be more effectively suppressed, and the durability of the adhesive layer at high temperature and/or high humidity can also be improved Sex (peel resistance). The aforementioned aromatic group-containing monomer is preferably phenoxyethyl (meth)acrylate.

The (meth)acrylic polymer preferably contains 0.01 to 3% by weight of the carboxyl group-containing monomer as a monomer unit, more preferably contains 0.05 to 1% by weight, and still more preferably contains 0.1 to 0.5% by weight.

The (meth)acrylic polymer preferably contains 0.01 to 1% by weight of the hydroxyl group-containing monomer as a monomer unit, more preferably contains 0.05 to 1% by weight, and still more preferably contains 0.1 to 0.5% by weight.

The (meth)acrylic polymer preferably contains 0.1 to 5% by weight of the nitrogen-containing monomer as a monomer unit, more preferably 0.5 to 3% by weight, and still more preferably 1.5 to 3% by weight.

The (meth)acrylic polymer preferably contains 1 to 20% by weight of the aromatic group-containing monomer as a monomer unit, more preferably 1 to 18% by weight, and still more preferably 1 to 15% by weight.

The weight average molecular weight of the aforementioned (meth)acrylic polymer is not particularly limited, but from the viewpoint of the coatability of the adhesive, it is preferably 1.5 million or less, and preferably 1.4 million or less, more preferably 1.3 million or less. In addition, from the viewpoint of adhesion characteristics, weather resistance, and heat resistance, the weight average molecular weight is generally 800,000 or more, and preferably 1 million or more.

The aforementioned (meth)acrylic polymer can be produced by a known method, and a radical polymerization method such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method and the like can be appropriately selected. As a radical polymerization initiator, various well-known materials of azo system and peroxide system can be used. The reaction temperature is usually around 50 to 80°C, and the reaction time is set to 1 to 8 hours. In addition, among the aforementioned production methods, the solution polymerization method is preferred, and the solvent of the (meth)acrylic polymer generally uses ethyl acetate, toluene, or the like.

唑啉系等。該等交聯劑可使用1種或可將2種以上組合使用。A crosslinking agent can be blended in the aforementioned adhesive. The cross-linking agent can improve the adhesiveness and durability, and can also ensure the reliability at high temperature and maintain the shape of the adhesive itself. As the crosslinking agent, isocyanate-based, epoxy-based, peroxide-based, metal chelate-based,

Oxazoline etc. These crosslinking agents may be used alone or in combination of two or more.

As the isocyanate-based crosslinking agent, an isocyanate compound can be used. Examples of the isocyanate compound include toluene diisocyanate, chlorobiphenyl diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, stubble diisocyanate, diphenylmethane diisocyanate, and hydrogenated Isocyanate monomers such as diphenylmethane diisocyanate, and addition products obtained by adding these isocyanate monomers with trimethylolpropane and the like are isocyanate compounds; triisocyanate compounds, biuret type compounds, and well-known Carbamate prepolymer isocyanate obtained by addition reaction of polyether polyol or polyester polyol, acrylic polyol, polybutadiene polyol and polyisoprene polyol.

The isocyanate-based crosslinking agent may be used alone or in combination of two or more, and the total content is preferably 0.01 to 2 parts by weight of the aforementioned isocyanate-based crosslinking agent relative to 100 parts by weight of the base polymer, and It is preferably made of 0.02 to 2 parts by weight, more preferably made of 0.05 to 1.5 parts by weight. The cross-linking agent may be suitably contained in consideration of cohesive force and prevention of peeling during the durability test.

Various peroxides can be used as the peroxide-based crosslinking agent. Peroxides can be exemplified by di(2-ethylhexyl) peroxydicarbonate, di(4-tertiary butylcyclohexyl) peroxydicarbonate, di-secondary butylperoxydicarbonate, tris Grade butyl peroxyneodecanoate, tertiary hexyl trimethyl acetate, tertiary butyl trimethyl acetate, dilauryl peroxide, di-n-octyl peroxide, 1, 1,3,3-tetramethylbutyl peroxyisobutyrate, 1,1,3,3-tetramethylbutyl peroxy 2-ethylhexanoate, bis(4-methylbenzoyl (Acyl) peroxide, dibenzoyl peroxide, tertiary butyl peroxyisobutyrate, etc. Among these, bis(4-tertiary butylcyclohexyl) peroxydicarbonate, dilauryl peroxide, and dibenzoyl peroxide, which have excellent cross-linking reaction efficiency, are particularly suitable.

The above peroxide may be used alone or in combination of two or more, but the total content is 0.01 to 2 parts by weight with respect to 100 parts by weight of the base polymer, and preferably contains 0.04 to 1.5 parts by weight It is preferably made from 0.05 parts to 1 part by weight. It can be appropriately selected within this range to adjust workability, reworkability, cross-linking stability, peelability, and the like.

In order to obtain an adhesive layer having the aforementioned adhesive force P ₀ ~P ₂ , the aforementioned adhesive agent preferably contains a silane coupling agent. The silane coupling agent may use any functional group that is suitable. The functional group may, for example, be a vinyl group, an epoxy group, an amine group, an acid anhydride group, a mercapto group, a (meth)acryl oxy group, an acetyl acetyl group, an isocyanate group, a styryl group, a polysulfide group, or the like. Specific examples include vinyl-containing silane coupling agents such as vinyl triethoxy silane, vinyl tripropoxy silane, vinyl triisopropoxy silane, and vinyl tributoxy silane; γ-ring Oxypropyloxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyl diethoxysilane, 2-(3,4- Epoxy cyclohexyl) ethyl trimethoxy silane and other epoxy-containing silane coupling agent; γ-aminopropyl trimethoxy silane, N-β-(aminoethyl)-γ-aminopropyl methyl dimethyl Oxysilane, N-(2-aminoethyl)3-aminopropylmethyldimethoxysilane, γ-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine, N-phenyl-γ-aminopropyltrimethoxysilane and other amine-containing silane coupling agents; 3-trimethoxysilylpropyl succinic anhydride and other anhydride-containing silane coupling agents; γ-mercaptopropylmethyl di Mercapto-containing silane coupling agent such as methoxy silane; p-styrene trimethoxy silane-containing silane coupling agent containing styrene group; γ-acryloyloxypropyltrimethoxysilane, γ-methacryloyloxy Silane coupling agent containing (meth)acryloyl group such as propyltriethoxysilane; isocyanate group containing silane coupling agent such as 3-isocyanatepropyltriethoxysilane; bis(triethoxysilylpropyl) ) Tetrasulfide and other silane coupling agents containing polysulfide groups. These can be used alone or in combination. Among these, from the viewpoint of producing an adhesive layer that is not easily peeled off from a glass substrate or the like even when exposed to an environment where condensation occurs, it is preferable to use an adhesive layer selected from the group consisting of epoxy groups, isocyanate groups, mercapto groups, A silane coupling agent of at least one functional group in the group consisting of an acid anhydride group and an amine group, and a silane coupling agent having an epoxy group, an isocyanate group, a mercapto group, or an acid anhydride group is more preferable.

In addition, from the viewpoint of producing an adhesive layer that is not easily peeled off from a glass substrate or the like even when exposed to an environment where condensation occurs, an oligomer type silane coupling agent can also be used. Here, the oligomer type means that the monomer is a polymer of 2 or more and less than 100 polymers, and the weight average molecular weight of the oligomer silane coupling agent is preferably about 300 to 30,000.

The oligomer type silane coupling agent includes, for example, epoxy group-containing silane coupling agent, mercapto group-containing silane coupling agent and isocyanate group-containing silane coupling agent, etc., and preferably thiol group-containing silane coupling agent and isocyanate group-containing Silane coupling agent. These can be used alone or in combination.

From the viewpoint of the durability of the adhesive layer under high temperature and/or high humidity environment, the epoxy equivalent of the epoxy group-containing silane coupling agent is preferably 250 to 600 g/mol, and preferably 250 to 500 g/mol, 280 ~400g/mol is better.

The aforementioned epoxy group-containing silane coupling agent preferably has two or more alkoxysilyl groups in the molecule. In addition, the amount of the alkoxy group of the epoxy group-containing silane coupling agent in the silane coupling agent is preferably 10 to 60% by weight, and preferably 20 to 50% by weight, more preferably 20 to 40% by weight. In addition, the epoxy group-containing silane coupling agent has one or more epoxy groups in the molecule, and it can be made from an adhesive that is not easily peeled off from a glass substrate or the like even when exposed to an environment where condensation occurs. From the viewpoint of the agent layer, it is preferable to have one epoxy group in the molecule. In addition, the epoxy group-containing silane coupling agent preferably has an aromatic ring in the molecule from the aforementioned viewpoint.

Examples of the oligomer type epoxy group-containing silane coupling agent having two or more alkoxysilyl groups in the molecule include X-12-981S, X-12-1231, and X-41- manufactured by Shin-Etsu Chemical Industry Co., Ltd. 1059A, X-41-1056, etc.

From the viewpoint of the durability of the adhesive layer under high temperature and/or high humidity environment, the mercapto equivalent of the aforementioned mercapto group-containing silane coupling agent is preferably 1000 g/mol or less, 800 g/mol or less, and 700 g/mol or less Below, it is more preferably 500 g/mol or less. In addition, the lower limit of the mercapto equivalent is not particularly limited, but is preferably 200 g/mol or more.

The aforementioned thiol group-containing silane coupling agent preferably has two or more alkoxysilyl groups in the molecule. In addition, the amount of alkoxy groups in the thiol-containing silane coupling agent in the silane coupling agent is preferably 10 to 60% by weight, more preferably 20 to 50% by weight, and further preferably 20 to 40% by weight.

Examples of oligomeric thiol-containing silane coupling agents having two or more alkoxysilyl groups in the molecule include X-41-1805, X-41-1810, X-41-1818 manufactured by Shin-Etsu Chemical Industry Co., Ltd., X-12-1156 etc.

The isocyanate equivalent of the isocyanate group-containing silane coupling agent is preferably 250 to 600 g/mol, and preferably 250 to 500 g/mol, and 280 to 400 g from the viewpoint of the durability of the adhesive layer under high temperature and/or high humidity environment /mol is better.

The aforementioned isocyanate group-containing silane coupling agent preferably has two or more alkoxysilyl groups in the molecule. In addition, the amount of alkoxy groups in the isocyanate group-containing silane coupling agent in the silane coupling agent is preferably 10 to 60% by weight, and preferably 20 to 50% by weight, and more preferably 20 to 40% by weight.

Examples of the oligomer type isocyanate group-containing silane coupling agent having two or more alkoxysilyl groups in the molecule include X-40-9318 and X-12-1159L manufactured by Shin-Etsu Chemical Co., Ltd.

The overall content of the silane coupling agent is preferably 0.05 to 5 parts by weight, and preferably 0.1 to 3 parts by weight relative to 100 parts by weight of the base polymer from the viewpoint of obtaining an adhesive layer having the aforementioned adhesive force P ₀ to P ₂ . It is more preferably 0.2 to 2 parts by weight.

Furthermore, it has a content of silane coupling agent (including oligomer type silane coupling agent) of at least one functional group selected from the group consisting of epoxy group, isocyanate group, mercapto group, acid anhydride group and amine group, by From the point of view of preparing an adhesive layer having the aforementioned adhesive forces P ₀ to P ₂ , it is preferably 0.01 to 3 parts by weight relative to 100 parts by weight of the base polymer, and more preferably 0.1 to 2 parts by weight, 0.1 to 1 part by weight The servings are better.

Moreover, from the viewpoint of improving the reworkability, the adhesive preferably contains a reworker. The aforementioned heavy industry lifting agent is a chemical substance having a polar group, which is easy to interact at the glass interface and is easy to segregate at the glass interface. Examples of the heavy-duty lifting agent include diols having an alkoxy group such as EO and PO, oligomers having a perfluoroalkyl group, and polyether compounds having a reactive silicon group. As the polyether compound, for example, the one disclosed in Japanese Patent Laid-Open No. 2010-275522 can be used.

Examples of the polyether compound having a reactive silicon group include MS polymers S203, S303, and S810 manufactured by KANEKA; SILYL EST250 and EST280; SAT10, SAT200, SAT220, SAT350, SAT400, and EXCESTAR S2410 and S2420 manufactured by Asahi Glass Co., Ltd. or S3430 etc.

The content of the heavy lifting agent is preferably 0.001 parts by weight or more, more preferably 0.01 parts by weight or more, and still more preferably 0.1 parts by weight or more, and preferably 10 parts by weight or less, more preferably 5 parts relative to 100 parts by weight of the base polymer. Below 1 part by weight, it is more preferably below 2 parts by weight, and still more preferably below 1 part by weight. If the content of the heavy-duty lifting agent is less than 0.001 parts by weight, it will be difficult to increase the heavy-duty workability of the adhesive layer, and if it is greater than 10 parts by weight, the adhesive properties of the adhesive layer will tend to decrease.

Moreover, the aforementioned adhesive preferably contains an antistatic agent. When manufacturing a liquid crystal display device, when the single-sided protective polarizing film with an adhesive layer is attached to a liquid crystal panel, the release film is peeled off from the adhesive layer of the single-sided protective polarizing film with an adhesive layer, and the release The mold film will generate static electricity. In addition, when a single-sided protective polarizing film with an adhesive layer is bonded to a liquid crystal panel, if a bonding error occurs, the polarizing film must be peeled off, but static electricity is generated when the polarizing film is peeled off. The generated static electricity will affect the orientation of the liquid crystal in the liquid crystal display device and cause a bad situation. In addition, when the liquid crystal display device is used, display unevenness caused by static electricity may sometimes occur. By adding an antistatic agent to the adhesive, the antistatic function of the adhesive layer on the single side of the adhesive layer to protect the polarizing film can be given, thereby preventing these undesirable conditions.

The antistatic agent is not particularly limited, and examples thereof include ionic compounds such as onium-anion salts and alkali metal salts. We believe that if an ionic compound is added, the ionic compound will overflow the surface of the adhesive layer, thereby effectively exhibiting antistatic function. On the other hand, when the ionic compound comes into contact with the polarizer, the optical characteristics such as the degree of polarization may decrease. From the viewpoint of suppressing the aforementioned reduction in optical characteristics, it is particularly preferable to use an alkali metal salt.

As the alkali metal salt, an organic salt or an inorganic salt of an alkali metal can be used. The alkali metal salt may be used alone or in combination.

Examples of the alkali metal ion constituting the cationic part of the alkali metal salt include ions of lithium, sodium, and potassium. Among these alkali metal ions, lithium ions are preferred.

The anion portion of the alkali metal salt may be composed of organic substances or inorganic substances. Constituting the organic salt of the anion portion, may be used for example ^{_{CH 3 COO -, CF 3 COO}} -, CH 3 SO 3 -, CF 3 SO 3 -, (CF 3 SO 2) 2 N -, (CF 3 SO 2) ^{_{3 C -, C 4 F 9}} SO 3 -, (C 2 F 5 SO 2) 2 N -, C 3 F 7 COO -, (CF 3 SO 2) (CF 3 CO) N -, - O 3 S ( ^{_{CF 2) 3 SO 3 -,}} PF 6 -, CO 3 2- and the like. In particular, the anion portion containing a fluorine atom is suitable for use because an ionic compound with excellent ion dissociation properties can be obtained. Inorganic anion portion constituting the available ^{Cl -, Br -, I -} , AlCl 4 -, Al 2 Cl 7 -, BF 4 -, PF 6 -, ClO 4 -, NO 3 -, AsF 6 -, SbF 6 -, ^{_{NbF 6 -, TaF 6-, (}} CN) 2 N - and the like. In anionic moiety _{(CF 3 SO 2) 2 N} -, (C 2 F 5 SO 2) 2 N - and the like (acyl perfluoroalkylsulfonylimide) (PEI) is preferred, but especially (CF ₃ SO _{2) 2} N ^- shown (trifluoromethanesulfonyl) amide imide is preferred.

Specific examples of organic salts of alkali metals include sodium acetate, sodium alginate, sodium lignosulfonate, sodium toluenesulfonate, LiCF ₃ SO ₃ , Li(CF ₃ SO ₂ ) ₂ N, and Li(CF ₃ SO ₂ ) ₂ N, Li(C ₂ F ₅ SO ₂ ) ₂ N, Li(C ₄ F ₉ SO ₂ ) ₂ N, Li(CF ₃ SO ₂ ) ₃ C, KO ₃ S(CF ₂ ) ₃ SO ₃ K, LiO ₃ S(CF ₂ ) ₃ SO ₃ K, etc. Among them, LiCF ₃ SO ₃ , Li(CF ₃ SO ₂ ) ₂ N, Li(C ₂ F ₅ SO ₂ ) ₂ N, Li(C ₄ F ₉ SO ₂ ) ₂ N, Li(CF ₃ SO ₂ ) ₃ C, etc., Li(CF ₃ SO ₂ ) ₂ N, Li(C ₂ F ₅ SO ₂ ) ₂ N, Li(C ₄ F ₉ SO ₂ ) ₂ Fluorine-containing lithium imide salts such as N are preferred, and (perfluoroalkylsulfonyl) lithium imide salts are particularly preferred.

In addition, examples of the inorganic salts of alkali metals include lithium perchlorate and lithium iodide.

The content of alkali metal salt in the adhesive is preferably 0.001 to 5 parts by weight relative to 100 parts by weight of the base polymer. When the aforementioned alkali metal salt is less than 0.001 part by weight, the effect of improving antistatic performance may be insufficient. The content of the aforementioned alkali metal salt is preferably 0.01 parts by weight or more, and more preferably 0.1 parts by weight or more. On the other hand, if the content of the alkali metal salt exceeds 5 parts by weight, the durability may be insufficient. The content of the aforementioned alkali metal salt is preferably 3 parts by weight or less.

The method for forming the adhesive layer can be produced by, for example, applying the adhesive to the separator and the like after peeling treatment, drying and removing the polymerization solvent, etc. to form an adhesive layer, and transferring it to one side A method of protecting the polarizer side of the polarizing film (the polarizer in the aspect of FIG. 1); or a method of forming the adhesive layer on the polarizer side after applying the adhesive and drying to remove the polymerization solvent. In addition, for the application of the adhesive, one or more solvents other than the polymerization solvent may be appropriately added.

The thickness of the adhesive layer is not particularly limited, but it is preferably 25 μm or less, more preferably 23 μm or less, and even more preferably 20 μm from the viewpoint of effectively suppressing defects caused by the nano slit and taking into account both excellent adhesive properties and reworkability. Below; and, it is preferably 10 μm or more, more preferably 12 μm or more, and still more preferably 15 μm or more.

It is better to use polysilicone release liner for the separated parts after stripping treatment. In the step of coating the adhesive of the present invention on the lining material and drying it to form an adhesive layer, the method of drying the adhesive may be an appropriate and appropriate method depending on the purpose. It is preferable to use a method in which the above coating film is overheated and dried. The heating and drying temperature is preferably 40°C to 200°C, more preferably 50°C to 180°C, and particularly preferably 70°C to 170°C. By setting the heating temperature within the above range, an adhesive having excellent adhesive properties can be obtained.

The appropriate drying time can be adopted as the drying time. The above drying time is preferably 5 seconds to 20 minutes, more preferably 5 seconds to 10 minutes, and particularly preferably 10 seconds to 5 minutes.

Various methods can be used to form the adhesive layer. Specific examples include roll coating, contact roll coating, gravure coating, reverse coating, roll brush, spray cloth, dip roll coating, bar coating, knife coating, and air knife coating , Curtain coating, lip coating, extrusion coating method using die coater, etc.

When the adhesive layer is exposed, the peeled sheet (separator) can be used to protect the adhesive layer until it is ready for practical use.

Examples of constituent materials of the separator include plastic films such as polyethylene, polypropylene, polyethylene terephthalate, and polyester films; porous materials such as paper, cloth, and non-woven fabric; meshes, and foamed sheets , Metal foil, and other appropriate laminates such as laminates, etc., but from the viewpoint of excellent surface smoothness, it is suitable to use plastic film.

The plastic film is not particularly limited as long as it can protect the adhesive layer, and examples thereof include polyethylene film, polypropylene film, polybutene film, polypentadiene film, polymethylpentene film, and polyvinyl chloride. Film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-ethyl acetate copolymer film, etc.

The thickness of the aforementioned separator is usually 5 to 200 μm, preferably about 5 to 100 μm. The aforementioned separator can also be subjected to mold release and antifouling treatment using polysilicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agents, silica powder, etc., as well as coating type, Antistatic treatment such as kneading type and evaporation type. In particular, by appropriately performing peeling treatments such as polysiloxane treatment, long-chain alkyl treatment, and fluorine treatment on the surface of the separator, the peelability from the adhesive layer can be further improved.

>Surface protection film> A surface protective film can be provided on the single-sided protective polarizing film with an adhesive layer. The surface protection film usually has a base material film and an adhesive layer, and protects the polarizer through the adhesive layer.

From the viewpoint of inspection and management, the substrate film of the surface protection film can be selected to have isotropic or nearly isotropic film materials. Examples of the film material include polyester-based resins such as polyethylene terephthalate films, cellulose-based resins, acetate-based resins, polyether-based resins, polycarbonate-based resins, and polyamide-based resins. Polyimide-based resin, polyolefin-based resin, acrylic resin-like transparent polymer. Among them, polyester resins are suitable. The base film can be used in the form of a laminate of one or more film materials, or an extension of the aforementioned film can be used. The thickness of the substrate film is usually 500 μm or less, preferably 10 to 200 μm.

The adhesive for forming the adhesive layer of the surface protection film can be appropriately selected from (meth)acrylic polymers, polysiloxane polymers, polyesters, polyurethanes, polyamides, polyethers, fluorine-based or Polymers such as rubbers are used as adhesives for base polymers. From the viewpoints of transparency, weather resistance, heat resistance, etc., an acrylic adhesive using an acrylic polymer as a base polymer is suitable. The thickness of the adhesive layer (dry film thickness) can be determined according to the required adhesive force. Usually it is about 1~100μm, preferably 5~50μm.

In addition, for the surface protection film, a peeling treatment layer may be provided on the opposite surface of the base film with the adhesive layer by a low-adhesion material such as polysiloxane treatment, long-chain alkyl treatment, or fluorine treatment.

>Other optical layers> The single-sided protective polarizing film with an adhesive layer of the present invention can be used in the form of an optical film formed by stacking with other optical layers in actual use. The optical layer is not particularly limited, and for example, one or more reflective plates and semi-transmissive plates, retardation plates (including 1/2 and 1/4 wavelength plates), viewing angle compensation films, etc. can be used to form liquid crystals The optical layer of a display device or the like. Particularly preferred is a reflective polarizing film or a semi-transmissive polarizing film formed by laminating a reflective plate or a semi-transmissive reflective plate on a single-sided protective polarizing film with an adhesive layer of the present invention, and a single-sided protective polarizing film with an adhesive layer The film is laminated with an elliptical polarized film or a circular polarized film formed by a retardation plate, a polarized film with a single-sided protective polarizing film attached with an adhesive layer, and a polarized film with a wide viewing angle formed with a viewing angle compensation film, or with a single-sided adhesive layer A polarizing film formed by protecting a polarizing film and then laminating a brightening film.

The optical film formed by laminating the above-mentioned optical layer on the single-sided protective polarizing film with an adhesive layer can also be formed in a layer-by-layer manner in the manufacturing process of liquid crystal display devices, etc., but the optical film is laminated in advance It has advantages in quality stability and assembly operations, and has the advantage of improving the manufacturing steps of liquid crystal display devices. For lamination, an appropriate bonding mechanism such as an adhesive layer can be used. When the above-mentioned single-sided protective polarizing film with an adhesive layer or other optical layer is adhered, the optical axis of the other can be set to an appropriate arrangement angle according to the desired phase difference characteristics.

The single-sided protective polarizing film or optical film with an adhesive layer of the present invention can be suitably used in the formation of various image display devices such as liquid crystal display devices and organic EL display devices. The formation of the liquid crystal display device can be carried out according to conventional knowledge. That is, the liquid crystal display device is generally formed by appropriately assembling the liquid crystal cell, the single-sided protective polarizing film or optical film with an adhesive layer, and optionally the lighting system and incorporating the driving circuit, etc. The invention is not particularly limited except that the single-sided protective polarizing film or optical film with an adhesive layer of the present invention is used, and can be conventionally known. For the liquid crystal cell, any type such as IPS type, VA type, etc. can also be used, but the IPS type is particularly ideal.

A liquid crystal display device that can be provided with a single-sided protective polarizing film or optical film with an adhesive layer on one or both sides of the liquid crystal cell, or a suitable liquid crystal display device that uses a backlight or a reflective plate for the lighting system. At this time, the single-sided protective polarizing film or optical film with an adhesive layer of the present invention can be disposed on one side or both sides of the liquid crystal cell. When a single-sided protective polarizing film or optical film with an adhesive layer is provided on both sides, they may be the same or different. In addition, when forming a liquid crystal display device, suitable components such as a diffusion plate, an anti-glare layer, an anti-reflection film, a protective plate, a prism array, a lens array sheet, a light diffusion plate, a backlight, etc. can be arranged at appropriate positions 1 Layer or more than 2 layers.

>Continuous manufacturing method of image display device> The above-mentioned image display device is preferably manufactured by a continuous manufacturing method (roll-to-roll method), which includes the steps of: winding a wound body (roll) of polarizing film protected from the single side of the adhesive layer of the present invention The single-sided protective polarizing film with the adhesive layer released and transported by the separating member is continuously attached to the surface of the image display panel through the adhesive layer. Since the single-sided protective polarizing film with an adhesive layer of the present invention is a very thin film, if it is cut into sheets (sheet cutting), it will be attached to the image display panel one by one (also called "Sheet to panel (sheet to panel) method", it is more difficult to handle when conveying the sheet or attaching to the display panel, so that the single-sided protective polarizing film (sheet) with an adhesive layer in these processes is subject to The risk of huge mechanical shocks (such as bending caused by adsorption) increases. In order to reduce this risk, countermeasures such as the use of a thick surface protective film with a base film thickness of 50 μm or more are required. However, according to the method of facing the web, the single-sided protective polarizing film with an adhesive layer is not cut into sheets (sheet cutting), but a continuous separation member is used to stably transport the film from the web to the image display panel And directly attached to the image display panel, so without using a thick surface protection film can greatly reduce the above risks. As a result, coupled with the use of an adhesive layer that has been controlled so that the film thickness and storage elastic modulus satisfy a predetermined relationship to mitigate the mechanical impact, it is possible to produce high-speed continuous production of nano-slits with effectively suppressed image display panels .

FIG. 5 is a schematic diagram showing an example of a continuous manufacturing system of a liquid crystal display device using a roll-to-roll method. As shown in FIG. 5, the continuous manufacturing system 100 of a liquid crystal display device includes a conveying section X that conveys a series of liquid crystal display panels P, a first polarizing film supply section 101a, a first bonding section 201a, and a second polarizing film supply section 101b And the second bonding portion 201b. In addition, the single-sided protective polarizer film-coated body (first roll) 20a with the first adhesive layer and the single-sided protective polarizer film-rolled body (second roll) 20b with the second adhesive layer It is used in the aspect shown in FIG. 1 having an absorption axis in the longitudinal direction.

(Conveying Department) The conveying section X can convey the liquid crystal display panel P. The conveying section X is composed of a plurality of conveying rollers, suction plates, and the like. The transport unit X includes an arrangement replacement part 300 between the first bonding part 201a and the second bonding part 201b, and the arrangement replacement part 300 is used to replace the long side and the short side of the liquid crystal display panel P relative to the liquid crystal display panel P The arrangement relationship of the transportation direction (for example, the liquid crystal display panel P is rotated horizontally by 90°). In this way, the single-sided protective polarizing film 21 a with the first adhesive layer and the single-sided protective polarizing film 21 b with the second adhesive layer can be bonded to the liquid crystal display panel P in a orthogonally polarized relationship.

(1st polarizing film supply unit) The first polarizing film supply unit 101a continuously supplies the single-sided protective polarizing film (with surface protective film) 21a of the first adhesive layer with the first adhesive layer released from the first roll 20a and conveyed by the separator 5a to the first bonding部201a. The first polarizing film supply unit 101a includes a first release unit 151a, a first cutting unit 152a, a first peeling unit 153a, a first take-up unit 154a, a plurality of conveying roller units, and accumulation units such as floating rollers.

The first release portion 151a has a release shaft on which the first roll 20a can be provided, and a single-sided protective polarizing film 21a with a tape-shaped adhesive layer provided with a separator 5a can be released from the first roll 20a.

The first cutting section 152a includes a cutting mechanism such as a cutter and a laser device, and an adsorption mechanism. The first cutting portion 152a can retain the separator 5a while cutting the single-sided protective polarizing film 21a of the tape-shaped first adhesive layer with a predetermined length in the width direction. However, a single-sided protective polarizing film 21a (optical film roll with cut marks) having a strip-shaped adhesive layer with a plurality of cutting lines formed with a predetermined length in the width direction on the separator 5a is stacked as the first When one roll of material 20a is used, the first cutting section 152a is unnecessary (the same applies to the second cutting section 152b described later).

The first peeling portion 153a folds the separator 5a inward to peel the single-sided protective polarizing film 21a of the first adhesive layer from the separator 5a. The first peeling portion 153a may be, for example, a wedge member or a roller.

The first winding portion 154a can wind the separator 5a from which the single-sided protective polarizing film 21a from which the first adhesive layer has been peeled off. The first winding section 154a has a winding shaft, and the winding shaft is provided with a roller for winding the separator 5a.

(1st bonding part) The first bonding portion 201a continuously bonds the single-sided protective polarizing film 21a of the first adhesive layer peeled through the first peeling portion 153a, and the single-sided protective polarizing film 21a of the first adhesive layer is continuously bonded through the adhesive layer of the first adhesive layer To the liquid crystal display panel P conveyed via the conveying section X (first bonding step). The first bonding portion 81 is configured by having a pair of bonding rollers, and at least one of the bonding rollers is configured by a driving roller.

(Second Polarizing Film Supply Section) The second polarizing film supply unit 101b continuously supplies the single-sided protective polarizing film (with surface protective film) 21b of the second adhesive layer released from the second roll 20b and conveyed by the separator 5b to the second bonding部201b. The second polarizing film supply unit 101b includes a second release unit 151b, a second cutting unit 152b, a second peeling unit 153b, a second take-up unit 154b, a plurality of transport roller units, an accumulation unit such as a floating roller, and the like. In addition, the second releasing portion 151b, the second cutting portion 152b, the second peeling portion 153b, and the second winding portion 154b are each different from the first releasing portion 151a, the first cutting portion 152a, and the first peeling portion 153a. The first winding unit 154a has the same configuration and function.

(Second bonding section) The second bonding portion 201b continuously bonds the single-sided protective polarizing film 21b of the second adhesive layer peeled off through the second peeling portion 153b, and the single-sided protective polarizing film 21b adhesive layer through the second adhesive layer To the liquid crystal display panel P conveyed via the conveying section X (second bonding step). The second bonding portion 201b includes a pair of bonding rollers, and at least one of the bonding rollers is configured by a driving roller. Examples

The following examples will be given to illustrate the present invention, but the present invention is not limited to the examples shown below. In addition, the parts and% in each case are based on weight. Below, all room temperature storage conditions that are not specified are 23°C and 55%RH.

>Making single-sided protective polarizing film> (Make polarizer) Corona treatment is applied to one side of the substrate of amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) film (thickness: 100 μm) with a water absorption of 0.75% and Tg75°C. The treated surface was coated with polyvinyl alcohol (degree of polymerization 4200, degree of saponification 99.2 mol%) and acetylacetate modified PVA (degree of polymerization 1200, acetylated acetylated) at a ratio of 9:1. The quality is 4.6%, the saponification degree is 99.0 mol% or more, an aqueous solution manufactured by Nippon Synthetic Chemical Industry Co., Ltd. under the trade name "Gohsefimer Z200") is dried, and a PVA-based resin layer with a thickness of 11 μm is formed to produce a laminate. The obtained laminate was uniaxially stretched in the longitudinal direction (longitudinal direction) by 2.0 times in the longitudinal direction (longitudinal direction) between rolls with different peripheral speeds in a 120° C. oven (air assisted stretching process). Next, the laminate was immersed in an insoluble bath (a boric acid aqueous solution obtained by blending 4 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30°C for 30 seconds (insoluble treatment). Next, it was immersed in a dyeing bath at a liquid temperature of 30°C, and the iodine concentration and the immersion time were adjusted at the same time to make the polarizing plate a predetermined transmittance. In this example, it was immersed in an aqueous iodine solution obtained by mixing 0.2 parts by weight of iodine and 1.0 parts by weight of potassium iodide with respect to 100 parts by weight of water for 60 seconds (dyeing treatment). Next, it was immersed in a crosslinking bath (a boric acid aqueous solution obtained by mixing 3 parts by weight of potassium iodide and 3 parts by weight of boric acid with respect to 100 parts by weight of water) at a liquid temperature of 30°C (crosslinking treatment) . Thereafter, while immersing the laminate in a boric acid aqueous solution at a liquid temperature of 70°C (an aqueous solution obtained by blending 4 parts by weight of boric acid and 5 parts by weight of potassium iodide with respect to 100 parts by weight of water), between rollers of different peripheral speeds Uniaxial extension is performed in the longitudinal direction (longitudinal direction) so that the total extension ratio is 5.5 times (extended in water). Thereafter, the laminate was immersed in a washing bath (aqueous solution obtained by mixing 4 parts by weight of potassium iodide with respect to 100 parts by weight of water) at a liquid temperature of 30° C. (washing treatment). Through the above procedure, an optical thin film laminate including a polarizer having a thickness of 5 μm and a boric acid content of 16% was obtained. The boric acid content in the polarizer is measured by the following method.

For the obtained polarizer, a Fourier Transform Infrared Spectrophotometer (FTIR) (manufactured by Perkin Elmer, trade name "SPECTRUM2000") was used to measure the peak value of boric acid (665cm ^-1 ) using ATR measurement using polarized light as the measurement light attenuation ) Intensity and reference peak (2941cm ^-1 ) intensity. From the obtained boric acid peak strength and the reference peak strength, the boric acid amount index is calculated using the following formula, and then the boric acid content (weight %) is determined from the calculated boric acid amount index using the following formula. (Boric acid amount index) = (intensity of boric acid peak 665 cm ^-1 ) / (reference peak strength of 2941 cm ^-1 ) (boric acid content (weight %)) = (boric acid amount index) × 5.54 + 4.1

(Make transparent protective film) Transparent protective film: The (meth)acrylic resin film having a thickness of 40 μm and having a lactone ring structure is subjected to corona treatment and then used.

(Making adhesive used for transparent protective film) 40 parts by weight of N-hydroxyethyl acrylamide (HEAA), 60 parts by weight of acryloyl morpholin (ACMO) and 3 parts by weight of photoinitiator "IRGACURE 819" (manufactured by BASF) are mixed to prepare ultraviolet rays Hardening adhesive.

(Preparation of single-sided protective polarizing film) On the surface of the polarizer of the optical film laminate, while applying the ultraviolet curing adhesive so that the thickness of the adhesive layer after curing becomes 0.5 μm, the transparent protection is bonded The film is then irradiated with ultraviolet rays as active energy rays to harden the adhesive. Ultraviolet irradiation uses a metal halide lamp filled with gallium, irradiation device: Light HAMMER10 manufactured by Fusion UV Systems, Inc., bulb: V bulb, peak illuminance: 1600mW/cm ² , cumulative exposure 1000/mJ/cm ² (wavelength 380~440nm), ultraviolet illuminance was measured using Sola-Check system manufactured by Solatell. Next, the amorphous PET substrate was peeled off to produce a single-sided protective polarizing film using a thin polarizer. Using the obtained single-sided protective polarizing film, the monomer transmittance T and the degree of polarization P of the polarizer were measured by the following method, the monomer transmittance T of the polarizer was 42.8%, and the polarization P of the polarizer was 99.99% .

The single transmittance T and the degree of polarization P of the polarizer of the single-sided protective polarizing film were measured using a spectroscopic transmittance analyzer with an integrating sphere (Dot-3c from Murakami Color Technology Research Institute). In addition, the polarization degree P is the transmittance (parallel transmittance: Tp) when two identical single-sided protective polarizing films are overlapped in parallel with the transmission axes of both of them and the transmittance when they are orthogonally overlapped with the transmission axes of the two ( Vertical transmittance: Tc) is obtained by applying the following formula. Polarization degree P(%)={(Tp-Tc)/(Tp+Tc)} ^1/2 ×100 Each transmittance is such that the complete polarization obtained by the Glan-Taylor polarizer is 100% And the Y value is obtained by correcting the visual performance with the 2 degree field of view (C light source) of JIS Z8701.

>Making double-sided protective polarizing film> A polyvinyl alcohol film with a thickness of 80 μm was dyed between rollers with different speed ratios at 30° C. and an iodine solution with a concentration of 0.3% by weight while being dyed for 1 minute and extended to 3 times. After that, it was immersed in an aqueous solution containing boric acid at a concentration of 4% by weight and potassium iodide at a concentration of 10% by weight at 60° C. for 0.5 minutes, and the elongation was performed simultaneously until the total elongation ratio reached 6 times. Next, by immersing in an aqueous solution containing potassium iodide at a concentration of 1.5% by weight at 30° C. for 10 seconds for washing, and then drying at 50° C. for 4 minutes, a polarizer with a thickness of 30 μm was produced. The saponified triacetyl cellulose film with a thickness of 80 μm is attached to both sides of the polarizer with a polyvinyl alcohol-based adhesive to form a double-sided protective polarizing film.

>Forming adhesive layer> (Preparation of acrylic adhesive 1) A monomer mixture containing 89.78 parts of n-butyl acrylate, 8 parts of methyl methacrylate, 1.5 parts of N-vinylpyrrolidone, 0.2 parts of acrylic acid and 0.48 parts of 4-hydroxybutyl acrylate is fed A four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a cooler. Then, with respect to 100 parts of the monomer mixture (solid content), 0.15 parts of 2,2´-azobisisobutyronitrile as a polymerization initiator was fed together with ethyl acetate, and nitrogen gas was introduced while slowly stirring. After nitrogen substitution, the temperature of the liquid in the flask was maintained at about 60°C, and polymerization reaction was carried out for 7 hours. Thereafter, ethyl acetate was added to the resulting reaction liquid to prepare an acrylic polymer solution whose solid content concentration was adjusted to 20% and the weight average molecular weight was 1.3 million.

The weight average molecular weight (Mw) of the acrylic polymer was measured using a GPC device (HLC-8220GPC) manufactured by Tosoh Co., Ltd. The measurement conditions are as follows. Sample concentration: 0.2% by mass (THF solution) Sample injection volume: 10μl Eluent: THF Flow rate: 0.6ml/min Measuring temperature: 40℃ Column: sample column; TSKguardcolumn SuperHZ-H (1pc) + TSKgel SuperHZM-H (2pcs) Reference column; TSKgel SuperH-RC (1 branch) Detector: Differential Refractometer (RI) The weight average molecular weight is determined in terms of polystyrene.

With respect to 100 parts of the solid content of the prepared acrylic polymer solution, 1.5 parts of lithium bis(trifluoromethanesulfonyl)amideimide (manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.), ethylmethyl Pyrrolidinium-bis(trifluoromethanesulfonyl)imide (manufactured by Tokyo Chemical Industry) 1 part, isocyanate-based crosslinking agent (manufactured by Mitsui Chemicals, trade name "TAKENATE D160N") 0.25 parts, peroxide-based Crosslinking agent (manufactured by Nippon Oil & Fats Corporation, trade name "NYPER BMT40SV") 0.25 parts, heavy industry lifter (manufactured by KANEKA CORPORATION, trade name "SAT10") 0.1 part, antioxidant (manufactured by BASF Japan, trade name "Irganox 1010" ) 0.3 parts, 0.2 parts of silane coupling agent containing acetyl acetyl group (manufactured by Kenken Chemical Co., Ltd., trade name "A-100") and 0.2 parts of oligomer type silane coupling agent containing thiol group (manufactured by Shin-Etsu Chemical Co., Ltd., trade name) "X-41-1810") 0.2 parts, and acrylic adhesive 1 was prepared.

(Preparation of acrylic adhesive 2~27) The monomer composition at the time of preparing the acrylic adhesive 1 was changed as shown in Table 1 and the polymerization conditions were adjusted, and the type and blending amount of the additives were changed as shown in Table 1, except for the same method A solution of acrylic polymer was prepared, and acrylic adhesives 2 to 27 were prepared.

(Forms adhesive layer) Next, the prepared acrylic adhesives 1 to 27 were uniformly coated on the surface of the polyethylene terephthalate film (separation film) treated with the silicone release agent using a spray coater And dried in an air circulation constant temperature oven at 155°C for 1 minute, and an adhesive layer was formed on the surface of each separation film.

[Table 1]

The compounds in Table 1 are as follows. BA: n-butyl acrylate 4HBA: 4-hydroxybutyl acrylate AA: Acrylic NVP: N-vinylpyrrolidone MMA: methyl methacrylate PEA: 2-phenoxyethyl acrylate NYPER BMT40SV: Dibenzoyl peroxide D160N: Isocyanate crosslinking agent (Mitsui Chemical Co., Ltd.) D110N: Isocyanate-based cross-linking agent (Mitsui Chemical Co., Ltd.) C/L: Trimethylolpropane/toluene diisocyanate adduct (manufactured by Tosoh Corporation, trade name "CORONATE L") SAT10: Heavy Industry Lifting Agent (manufactured by Kaneka) LiTFSi: Lithium bis(trifluoromethanesulfonyl)imide (manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd) EMPTFSi: ethylmethylpyrrolidinium-bis(trifluoromethanesulfonyl) amide imide (manufactured by Tokyo Chemical Industry) Irganox 1010: Antioxidant (manufactured by BASF Japan) A-100: Silane Coupling Agent Containing Acetyl Acetyl Group (manufactured by ZTE Chemical Co., Ltd.) X-41-1810: Oligomeric thiol-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.) KBM-573: N-phenyl-3-aminopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-1156: Oligomeric thiol-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.) X-40-9318: oligomer type isocyanate group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.) X-88-398: Silane coupling agent containing amine group (manufactured by Shin-Etsu Chemical Co., Ltd.) KBM-6803: N-2-(aminoethyl)-8-amineoctyltrimethoxysilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) X-12-5263H: Silane coupling agent containing amino alkoxy polyfunctional group (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-981S: Organosilane (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-1159L: Oligomer type isocyanate group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-1231: Silane coupling agent containing epoxy groups (manufactured by Shin-Etsu Chemical Co., Ltd.) X-41-1056: oligomer type epoxy group-containing silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd.) X-24-9591F: oligomer type silane coupling agent containing anhydride group (manufactured by Shin-Etsu Chemical Co., Ltd.) TMPS-E: Silane coupling agent containing amine group (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-967C: 3-trimethoxysilylpropyl succinic anhydride (manufactured by Shin-Etsu Chemical Co., Ltd.) KBM-3086: Silane coupling agent containing alkoxy polyfunctional group (manufactured by Shin-Etsu Chemical Co., Ltd.) KBE-9007N: Silane coupling agent containing isocyanate group (manufactured by Shin-Etsu Chemical Co., Ltd.) KBM-803: 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) X-12-1056ES: Silane coupling agent containing mercapto group (manufactured by Shin-Etsu Chemical Co., Ltd.) KBM-403: 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)

>Examples 1-19, Comparative Examples 1-11> >Make single-sided protective polarizing film with adhesive layer> The prepared adhesive layers were respectively attached to the polarizer side of the produced single-sided protective polarizing film, and single-sided protective polarizing films with adhesive layers were separately fabricated. >Making double-sided protective polarizing film with adhesive layer> The produced adhesive layers were respectively attached to one side of the produced double-sided protective polarizing film, and a double-sided protective polarizing film with an adhesive layer was separately fabricated.

The following measurements and evaluations were performed on the adhesive layer obtained above, the single-sided protective polarizing film with an adhesive layer and the double-sided protective polarizing film with an adhesive layer. The results are listed in Table 2.

>Suppression of nano slits: guitar shrapnel test> The prepared single-sided protective polarizing film with an adhesive layer and the double-sided protective polarizing film with an adhesive layer were cut to a size of 50 mm×150 mm (the absorption axis direction was 50 mm), which was used as Sample 11. The sample 11 was used by bonding the surface protective film 6 produced by the following method to the protective film 2 side.

(Surface protective film for testing) 94 parts by mass of 2-ethylhexyl acrylate (2EHA), 1 part by mass of N,N-diethylacrylamide (DEAA), and 1 part by mass of ethoxy diethylene glycol acrylate (EDE) , 4 parts by mass of 4-hydroxybutyl acrylate (HBA), 0.2 parts by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, 150 parts by mass of ethyl acetate, fed with a stirring blade , Thermometer, nitrogen introduction tube, cooler four-necked flask, introduce nitrogen while slowly stirring, maintain the liquid temperature in the flask at about 60 ℃, polymerization reaction for 5 hours to prepare an acrylic polymer solution ( 40% by mass). The aforementioned acrylic polymer has a weight average molecular weight of 570,000 and a glass transition temperature (Tg) of -68°C. The aforementioned acrylic polymer solution (40% by mass) was diluted with ethyl acetate to 20% by mass, and to this solution of 500 parts by mass (100 parts by mass of solid content), 2 parts by mass (2 parts by mass of solid content) was added Bis Tricyanurate isocyanate (made by Japan Polyurethane Industry Co., Ltd., Coronate HX: C/HX), 2 parts by mass (solid content 0.02 parts by mass) of dilauric acid diisocyanate Butyl tin (1% by mass ethyl acetate solution) was mixed and stirred to prepare an acrylic adhesive solution. The acrylic adhesive solution described above was applied to a transparent polyethylene terephthalate (PET) film (polyester film) with a thickness of 38 μm and heated at 130° C. for 1 minute to form an adhesive layer with a thickness of 15 μm, and Produce a surface protection film.

Next, as shown in the conceptual diagram of FIG. 3(A) and the cross-sectional view of FIG. 3(B), the release sheet (separator) is peeled from the sample 11 and attached to the glass through the exposed adhesive layer 4 On board 20. Then, a guitar shrapnel (manufactured by HISTORY, model "HP2H (HARD)") was applied to the central portion of the sample 11 (surface protection film 6 side) with a load of 200 g, and the absorption axis of the polarizer 1 was perpendicular to the sample 11 50 times of 100mm load load is repeated in the direction of the direction. The aforementioned load loading is performed at one place. In addition, the aforementioned load loading system is performed at a high speed (7.5 m/min). Next, after the sample 11 was left to stand in an environment of 80° C. for 1 hour, the sample 11 was checked for the presence of light-transmitting cracks according to the following criteria. ◎: 0~10 ○: 11~30 ×: 31 or more

FIG. 4 is an example of the following indicators for confirming the light transmission crack (nano slit a) of the single-sided protective polarizing film 11 with an adhesive layer in the guitar shrapnel test, and is an example of a microscope photo of the surface of the polarizing film. In FIG. 4(A), no light-transmitting cracks caused by the nano slit a are confirmed. In addition, FIG. 4(B) is a case where light-transmitting cracks caused by three nano slits a are generated in the absorption axis direction of the polarizer by heating. Fig. 4 is a sample with nano slits observed under an interference phase contrast microscope. When photographing the sample, the sample produced by the nano slit is arranged on the lower side of the sample with the nano slit (transmission side of the light source) in a manner of orthogonal polarization, and observed with transmitted light.

>Measurement of weight change rate> Put 50 mg of the prepared adhesive layer into the sample basket and set it on the scale of the device, then use a moisture adsorption and desorption measuring device (manufactured by Hiden, IGA-Sorp) to perform moisture adsorption and desorption Determination. The measurement conditions are as follows. The measured W ₀ and W _{1 are} substituted into the following formula (1) to calculate the weight change rate. Drying (pre-treatment to remove moisture in the adhesive layer): (100℃, dry, 1 hour) Procedure: (23℃, dry, 2 hours) (W ₀ )→(23℃, 55%RH, 5 hours) →(60℃, 95%RH, 5 hours) (W ₁ )→(23℃, 55%RH, 5 hours) Measurement mode: continuous weight change rate (%)={(W ₁ -W ₀ )/W ₀ }×100 (1) W ₀ = weight of the adhesive layer after drying the adhesive layer at 23° C. for 2 hours W ₁ = leaving the adhesive layer after drying at 23° C. 55% RH for 5 hours And the weight of the adhesive layer after being placed at 60℃95%RH for 5 hours

>Measure adhesive force and evaluate peeling> Use the prepared single-sided protective polarizing film with adhesive layer and the double-sided protective polarizing film with adhesive layer as samples. The aforementioned sample was attached to the surface of the alkali-free glass plate using a laminating machine, followed by an autoclave treatment at 50°C and 5 atm for 15 minutes to make it completely tight. After that, the adhesive force P ₀ (N/25 mm) when the polarizing film was peeled from the surface of the alkali-free glass plate under the conditions of a peeling temperature of 23° C., a peeling speed of 300 mm/min and a peeling angle of 90 degrees was measured using a heavy equipment. Then, the aforementioned sample was attached to the surface of the alkali-free glass plate using a laminator, followed by autoclave treatment at 50° C. and 5 atm for 15 minutes to make it fully adhered to obtain a laminate. Then, after immersing the produced laminate in water at 23° C. for 2 hours, the aforementioned laminate was taken out from the water. After that, the adhesive force P ₁ (N/25 mm) when the polarizing film was peeled from the surface of the alkali-free glass plate under the conditions of a peeling temperature of 23° C., a peeling speed of 300 mm/min, and a peeling angle of 90 degrees was measured. Then, after immersing the obtained laminate in water at 23° C. for 5 hours, the aforementioned laminate was taken out from the water. After that, the adhesion P ₂ (N/25 mm) when the polarizing film was peeled from the surface of the alkali-free glass plate under the conditions of a peeling temperature of 23° C., a peeling speed of 300 mm/min, and a peeling angle of 90 degrees was measured using a heavy equipment. Then, after immersing the obtained laminate in water at 23° C. for 500 hours, the aforementioned laminate was taken out from the water. After that, visually observe whether the polarizing film peels off, and evaluate according to the following criteria. ◎: No peeling was confirmed at all. ○: Wrinkles were confirmed at the ends of the polarizing film. ×: There was confirmed that there was obvious peeling.

>Durability Evaluation> The single-sided protective polarizing film with an adhesive layer and the double-sided protective polarizing film (15 inches) with an adhesive layer were peeled off, and attached to a non-alkali glass with a thickness of 0.7 mm (manufactured by Corning) using a laminator , EG-XG). Next, autoclave treatment was carried out at 50° C. and 0.5 MPa for 15 minutes to completely adhere the polarizing film to the alkali-free glass. Next, after putting them in the conditions of a heating oven (heating) at 80°C and a constant temperature and humidity machine (humidification) at 60°C/90%RH, after 500 hours, the polarizers were evaluated for peeling based on the following criteria . ◎: No peeling was confirmed at all. ○: There was peeling to such an extent that it could not be confirmed visually. △: Small flakes which can be confirmed visually are confirmed. ×: Obvious peeling was confirmed.

>Evaluation of conductive stability> After peeling off the prepared single-sided protective polarizing film with an adhesive layer and the double-sided protective polarizing film with an adhesive layer, the surface resistance of the adhesive surface was measured using MCP-HT450 manufactured by Mitsubishi Chemical Analytech Value (Ω/□). After the polarizing film was stored in a humidified environment at 60°C/90%RH for 500 hours, the surface resistance value of the surface of the adhesive was measured in the same manner as above. The change rate (%) of the surface resistance value was calculated by the following formula and evaluated according to the following criteria. Rate of change ΔR (%) = (surface resistance value after storage) × 100/ (surface resistance value before storage) (Evaluation criteria) 〇: 0≦ΔR>500 △: 500≦ΔR>700 ×: 700≦ΔR

[Table 2]

Industrial availability The single-sided protective polarizing film with an adhesive layer of the present invention can be used alone or in the form of a laminated optical film for image display devices such as liquid crystal display devices (LCDs) and organic EL display devices.

1‧‧‧ Polarizer 2‧‧‧Protection film 3‧‧‧ Adhesive layer, etc. 4‧‧‧Adhesive layer 5, 5a, 5b ‧‧‧ Separate parts 6, 6a, 6b ‧‧‧ surface protection film 10‧‧‧Single-sided protective polarizing film 11‧‧‧Single-sided protective polarizing film and sample with adhesive layer (Figure 3) 20‧‧‧Glass plate 20a, 20b‧‧‧Rolled body (coiled material) of single-sided protective polarizing film with adhesive layer 21a, 21b‧‧‧Single-sided protective polarizing film with adhesive layer (with surface protective film) 100‧‧‧Continuous manufacturing system of image display device 101a, 101b‧‧‧ Polarized film supply unit 151a, 151b‧‧‧ Release Department 152a, 152b‧‧‧ Cutting Department 153a, 153b 154a, 154b ‧‧‧ take-up department 201a, 201b ‧‧‧ Laminating Department 300‧‧‧Configuration replacement department a‧‧‧Nano slit b‧‧‧Penetrating crack P‧‧‧Image display panel X‧‧‧Conveying section of image display panel

1 is an example of a schematic cross-sectional view of a single-sided protective polarizing film with an adhesive layer of the present invention. FIG. 2 is an example of a conceptual diagram comparing nano slits and penetrating cracks generated in a polarizer. FIG. 3 is a schematic diagram illustrating nano slit-related evaluation items of Examples and Comparative Examples. FIG. 4 is an example of photographs showing cracks generated by nano slits related to the evaluation of Examples and Comparative Examples. 5 is an example of a schematic cross-sectional view of a continuous manufacturing system of an image display device.

1‧‧‧ Polarizer

2‧‧‧Protection film

3‧‧‧ Adhesive layer, etc.

4‧‧‧Adhesive layer

5‧‧‧ Separate parts

6‧‧‧Surface protection film

10‧‧‧Single-sided protective polarizing film

11‧‧‧Single-sided protective polarizing film with adhesive layer

Claims (20)

A single-sided protective polarizing film with an adhesive layer, characterized in that: it has: a single-sided protective polarizing film, which has a protective film only on one side of the polarizer; and, the polarizer of the single-sided protective polarizing film The side has an adhesive layer directly or has an adhesive layer across the coating layer; the adhesive layer contains a (meth)acrylic polymer as a base polymer, and the adhesive layer has a weight change rate calculated by the following formula (1) Is 1.1% or more, and the adhesive force P ₀ of the adhesive layer under the following conditions is 10 N/25 mm or less, and the adhesive force P ₁ under the following conditions is 1.6 N/25 mm or more; weight change rate (%) = { (W ₁ -W ₀ )/W ₀ }×100 (1) W ₀ = weight of the adhesive layer after drying the adhesive layer at 23° C. for 2 hours W ₁ = the adhesive layer after drying the foregoing The weight of the adhesive layer after placing it at 23°C 55%RH for 5 hours and at 60°C 95%RH for 5 hours. Adhesion P ₀ : Protect the polarizer film on one side of the aforementioned adhesive layer After being attached to the surface of alkali-free glass and subjected to an autoclave treatment at 50°C and 0.5atm for 15 minutes, the adhesive was peeled off under the conditions of a peeling temperature of 23°C, a peeling speed of 300mm/min and a peeling angle of 90 degrees. when the adhesion layer from the release surface of alkali-free glass; adhesive force P _1: attaching single-sided adhesive layer of the polarizing protective film adhesive layer adhered to the surface of alkali-free glass, and at 50 ℃, 0.5atm of Autoclave treatment was carried out under the conditions for 15 minutes to obtain a laminate. The laminate was immersed in water at 23°C for 2 hours. After removing the laminate from the water, the peeling temperature was 23°C, the peeling speed was 300 mm/min and the peeling angle The adhesive force when peeling the adhesive layer from the surface of the alkali-free glass under the condition of 90 degrees. The single-sided protective polarizing film with an adhesive layer according to claim 1, wherein the aforementioned (meth)acrylic polymer contains the following as a monomer unit: 50% by weight or more of alkyl (meth)acrylate (A), and its homopolymer has a glass transition temperature of less than 0°C; and 0.1 to 20% by weight of high Tg monomer (B), which is selected from the group consisting of (meth)acrylic acid alkyl ester (b1) and (meth)acryl-containing monomer (b2) At least one of the above, the glass transition temperature of the homopolymer of the (meth)acrylic acid alkyl ester (b1) is 0° C. or higher, and the glass of the homopolymer containing the (meth)acryloyl monomer (b2) The transition temperature is 0°C or higher and has a heterocyclic ring. The single-sided protective polarizing film with an adhesive layer as claimed in claim 2, wherein the (meth)acrylic polymer contains a polar monomer other than the (meth)acryl group-containing monomer (b2) as a monomer unit And the polar monosystem is at least one selected from the group consisting of nitrogen-containing monomers, carboxyl-containing monomers, hydroxyl-containing monomers, and aromatic-group-containing monomers. The single-sided protective polarizing film with an adhesive layer according to claim 3, wherein the nitrogen-containing monomer is a vinyl-based monomer having an internal amide ring. The single-sided protective polarizing film with an adhesive layer according to claim 4, wherein the vinyl monomer having an internal amide ring is a vinyl pyrrolidone monomer. The single-sided protective polarizing film with an adhesive layer according to claim 5, wherein the vinylpyrrolidone-based monomer is N-vinylpyrrolidone. The single-sided protective polarizing film with an adhesive layer according to any one of claims 3 to 6, wherein the (meth)acrylic polymer contains 0.1 to 5% by weight of the nitrogen-containing monomer as a monomer unit. The single-sided protective polarizing film with an adhesive layer according to any one of claims 3 to 7, wherein the (meth)acrylic polymer contains 0.01 to 3% by weight of the carboxyl group-containing monomer as a monomer unit. The single-sided protective polarizing film with an adhesive layer according to any one of claims 3 to 8, wherein the (meth)acrylic polymer contains 0.01 to 1% by weight of the hydroxyl group-containing monomer as a monomer unit. The single-sided protective polarizing film with an adhesive layer according to any one of claims 3 to 9, wherein the (meth)acrylic polymer contains 1 to 20% by weight of the aromatic group-containing monomer as a monomer unit . The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 10, wherein the weight average molecular weight of the aforementioned (meth)acrylic polymer is 1.5 million or less. The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 11, wherein the adhesive layer contains a silane coupling agent, and the silane coupling agent has a group selected from epoxy groups, isocyanate groups, mercapto groups , At least one functional group in the group consisting of acid anhydride group and amine group. The single-sided protective polarizing film with an adhesive layer according to claim 12, wherein the content of the silane coupling agent is 0.01 to 3 parts by weight relative to 100 parts by weight of the (meth)acrylic polymer. The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 13, wherein the thickness of the polarizer is 12 μm or less. The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 14, wherein the polarizer contains a polyvinyl alcohol-based resin and is configured to have optical characteristics represented by a single transmittance T and a degree of polarization P The condition of the following formula is satisfied: P>-(10 ^0.929T-42.4 -1)×100 (only, T>42.3), or P≧99.9 (only, T≧42.3). The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 15, wherein the polarizer contains boric acid at 25% by weight or less relative to the total amount of polarizers. The single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 16, wherein a separation member is provided on the adhesive layer. The single-sided protective polarizing film with an adhesive layer as claimed in claim 17 is a wound body. An image display device having a single-sided protective polarizing film with an adhesive layer according to any one of claims 1 to 16. A continuous manufacturing method of an image display device, comprising the steps of: releasing the adhesive agent that has been released from the wound body of the single-sided protective polarizing film with the adhesive agent layer as claimed in claim 18 and conveyed by the separating member The single-sided protective polarizing film of the layer is continuously attached to the surface of the image display panel through the aforementioned adhesive layer.

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