KR20190128629A - Adhesive layer, single protection polarizing film provided with adhesive layer, image display apparatus, and its continuous manufacturing method - Google Patents

Abstract

Abs(a): 상기 점착제층의 전반사 측정법에 의한 IR 측정에 있어서, 메틸(메트)아크릴레이트의 C-O-C 결합의 역대칭 신축 진동에서 유래되는 피크 흡광도
Abs(b): 상기 점착제층의 전반사 측정법에 의한 IR 측정에 있어서, 상기 알킬(메트)아크릴레이트의 C-O-C 결합의 역대칭 신축 진동에서 유래되는 피크 흡광도
Abs(c): 상기 점착제층의 전반사 측정법에 의한 IR 측정에 있어서, 800∼900cm^-1의 범위에 있어서의 가장 낮은 흡광도An object of this invention is to provide the single protection polarizing film provided with the adhesive layer which can suppress the defect by a nano slit, and is excellent in antistatic function and rework property, and the adhesive layer which has the said adhesive layer. . The adhesive layer of this invention contains a (meth) acrylic-type polymer as a base polymer, The said (meth) acrylic-type polymer is a monomer unit, Alkyl (meth) acrylate of 2-12 carbon atoms of an alkyl group, and methyl (meth) ) The acrylate is contained, and the said adhesive layer satisfy | fills following formula (1), It is characterized by the above-mentioned.

Abs (a): Peak absorbance derived from antisymmetric stretching vibration of COC bond of methyl (meth) acrylate in IR measurement by total reflection measurement method of the pressure-sensitive adhesive layer
Abs (b): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the COC bond of the alkyl (meth) acrylate
Abs (c): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the lowest absorbance in the range of 800 ~ 900cm ^-1

Description

Adhesive layer, single protection polarizing film provided with adhesive layer, image display apparatus, and its continuous manufacturing method

This invention relates to the single protection polarizing film provided with the adhesive layer and the adhesive layer which has the said adhesive layer. The single protection polarizing film provided with the said adhesive layer can form image display apparatuses, such as a liquid crystal display device (LCD) and an organic electroluminescence display, as this alone or as an optical film which laminated | stacked this.

In a liquid crystal display device, it is necessary to arrange | position a polarizing film on both sides of the glass substrate which forms the liquid crystal panel surface from the image formation system. Generally, the thing which bonded the protective film to the single side | surface or both surfaces of the polarizer which consists of a polyvinyl alcohol-type film and dichroic materials, such as iodine, by the polyvinyl alcohol-type adhesive agent etc. is used for a polarizing film.

When attaching the said polarizing film to a liquid crystal cell etc., an adhesive is used normally. Moreover, since it has the advantages of being able to fix a polarizing film in an instant, not having a drying process for fixing a polarizing film, etc., an adhesive is previously provided as an adhesive layer on the single side | surface of a polarizing film. . That is, the single protection polarizing film provided with an adhesive layer is generally used for adhesion of a polarizing film.

In addition, the polarizing film and the piece protection polarizing film provided with an adhesive layer are a polarizer in the severe environment of thermal shock (for example, the heat shock test which repeats -30 degreeC and 80 degreeC temperature conditions, and 100 degreeC high temperature test). There is a problem that cracks (through cracks) are likely to occur in the entire absorption axis direction of the polarizer due to the change in the shrinkage stress. That is, the single protection polarizing film provided with the pressure-sensitive adhesive layer did not have sufficient durability due to thermal shock in the harsh environment. In particular, from the viewpoint of thinning, in the single protection polarizing film provided with the adhesive layer using the single protection polarizing film which provided the protective film only in the single side | surface of a polarizer, durability by the said thermal shock was inadequate. In addition, the through crack which generate | occur | produces by the said thermal shock was easy to generate | occur | produce when the size of a polarizing film became large.

For example, in order to give high durability in high temperature environment, as an adhesive layer of the single protection polarizing film provided with an adhesive layer, the storage elastic modulus in 23 degreeC is 0.2-10 Mpa, and thickness is 2 micrometers or more 25 It is proposed to use what is less than micrometers (patent document 1). Moreover, in order to provide favorable durability even in high temperature environment, in the polarizing plate in which the pressure sensitive adhesive layer is provided in the single side | surface of a polarizer, and the protective layer which consists of a transparent resin film is provided in the other side of the polarizer, as said pressure sensitive adhesive layer, 23 It is proposed to use what shows the storage elastic modulus of 0.15-1 Mpa in the temperature range of -80 degreeC (patent document 2). Moreover, in order to suppress generation | occurrence | production of the said through crack, as an adhesive layer of the single protection polarizing film provided with an adhesive layer, the shrinkage force of the direction orthogonal to the absorption axis of a polarizer is controlled small, and also in an adhesive layer at 23 degreeC It is proposed to use what has a storage elastic modulus 0.20 Mpa or more (patent document 3). Moreover, thinning is performed also about a polarizer, and the thin polarizer which shows the high orientation which controlled the optical characteristic of a single transmittance and a polarization degree, for example is proposed (patent document 4).

However, in patent document 1, even if durability was satisfied, since the thickness of the polarizer was large at 25 micrometers, generation | occurrence | production of the through crack by the shrinkage stress of the polarizer could not be prevented. Moreover, in patent documents 1-3, since the durability improvement of the single protection polarizing film provided with the adhesive layer is made into a subject, boric acid used for a polarizer is comparatively many. When the boric acid contained in a polarizer is more than a specific value, since the bridge | crosslinking by boric acid is accelerated | stimulated at the time of heating, and the shrinkage stress of a polarizer becomes large, it turned out that it is unpreferable from a viewpoint of suppressing generation of a through crack. That is, in Patent Literatures 1 to 3, through cracks can be prevented to some extent by the control of the storage elastic modulus of the pressure-sensitive adhesive layer, it cannot be said that the generation of through cracks can be sufficiently suppressed.

On the other hand, thickness reduction is performed also about a polarizer. When the polarizer used for the single protection polarizing film provided with an adhesive layer was made thin, the change of the shrinkage stress of a polarizer becomes small. Therefore, according to the thinned polarizer, it turned out that generation of the said through crack can be suppressed.

However, in the piece protection polarizing film provided with the adhesive layer in which generation | occurrence | production of the said through crack was suppressed, when controlling an optical characteristic like patent document 4, and making a polarizer thin (for example, when it is set to thickness of 12 micrometers or less) ), When a mechanical impact is loaded on the polarizing protective polarizing film having the pressure-sensitive adhesive layer (including a case where a load due to convex bending is applied to the polarizer side), the ultra-fine slit (hereinafter, Also known as nano slits). It turned out that the said nano slit arises regardless of the size of a polarizing film. Moreover, it turned out that the said nano slit does not generate | occur | produce when the positive protective polarizing film which has a protective film on both surfaces of a polarizer is used. In the case where a through crack occurs in the polarizer, since the stress around the through crack is released, the through crack does not occur adjacently. However, it was found that the nano slit is generated adjacent to each other. . In addition, although the through-cracks have progression | extension which extends to the absorption axis direction of the polarizer which the crack generate | occur | produced, it turned out that a nanoslit does not have the said progression. Thus, the said nano slit is a new subject which arises when a polarizer is made thin and the optical characteristic is controlled to a predetermined range in the single protection polarizing film in which generation | occurrence | production of a through crack was suppressed, The said through crack conventionally known It turned out that it is a subject which arises by a different phenomenon from.

In addition, since the said nano slit is ultrafine, it cannot detect in a normal environment. Therefore, even if the nano slit generate | occur | produced in the polarizer, it is difficult only to confirm the defect by the light leakage of the single protection polarizing film provided with an adhesive layer. That is, usually, a piece protection polarizing film is produced in elongate film shape and defect inspection by automatic optical inspection, but it is difficult to detect a nano slit as a defect by this defect inspection. The defect by the said nano slit can be detected when a single protection polarizing film provided with an adhesive layer is bonded to the glass substrate of an image display panel, etc., and when it is placed in a heating environment, and a nano slit spreads in the width direction (for example, And the presence or absence of the light leakage).

Therefore, in the single protection polarizing film provided with the adhesive layer using a thin polarizer, it is desired to suppress not only through cracks but the defect by a nano slit. Furthermore, in the single protection polarizing film provided with an adhesive layer, since it is thin compared with the polarizing film of the dual protection structure which has a protective film on both sides, breakage and a break | rupture occur easily in a polarizing film at the time of handling.

In order to suppress the defect by the said nano slit, the technique of providing a transparent layer (coating layer) between the polarizer and the adhesive layer of the single protection polarizing film provided with an adhesive layer is proposed (patent document 5). By providing a transparent layer, since the said polarizing film becomes difficult to bend when an external stress is applied to the said polarizing film, generation | occurrence | production of a nano slit can be suppressed.

In addition, when affixing the single protection polarizing film provided with an adhesive layer to a liquid crystal cell at the time of manufacture of a liquid crystal display device, peeling of a release film from the adhesive layer of the single protection polarizing film provided with an adhesive layer, peeling of the said release film Static electricity is generated by The static electricity generated in this manner affects the liquid crystal alignment inside the liquid crystal display device, resulting in a defect. In addition, display nonuniformity by static electricity may arise at the time of use of a liquid crystal display device. Although generation | occurrence | production of static electricity can be suppressed by forming an antistatic layer in the outer surface of a polarizing film, for example, there exists a problem that the effect is small and it cannot fundamentally prevent static electricity generation. Therefore, in order to suppress generation | occurrence | production at the fundamental position of static electricity generation, it is calculated | required to give antistatic function to an adhesive layer. As a means of providing an antistatic function to an adhesive layer, mix | blending an ionic compound with the adhesive which forms an adhesive layer, for example is proposed (patent documents 6-8). In detail, in patent document 6, the adhesive composition for optical films which mix | blended the alkali metal salt and / or organic cation-anion salt is proposed. In patent document 7, the adhesive composition containing an onium-anion salt and an alkali metal salt is proposed as a raw material of the adhesive layer of the polarizing film provided with an adhesive layer. In patent document 8, the adhesive composition containing an alkali metal salt is proposed as a raw material of the adhesive layer of an adhesive polarizing plate.

Japanese Patent Laid-Open No. 2010-44211 Japanese Patent Publication No. 2008-197309 Japanese Patent Publication No. 2013-72951 Japanese Patent No.4751481 Japanese Patent No. 6077618 Japanese Patent Publication No. 2015-199942 Japanese Patent Publication No. 2014-48497 Japanese Patent Laid-Open No. 2012-247574

However, in the case where the ionic compound is blended into the pressure-sensitive adhesive layer of the single protective polarizing film having the pressure-sensitive adhesive layer, when the single protective polarizing film having the pressure-sensitive adhesive layer is exposed to a humidified environment, the antistatic function of the pressure-sensitive adhesive layer decreases or the polarizer Is deteriorated, so-called color omission occurs, and there exists a problem of the polarization degree falling.

Moreover, when bonding the single protection polarizing film provided with an adhesive layer to the glass substrate which forms the surface of a liquid crystal panel, and a foreign material or a bubble mixes and a bonding miss arises, it is necessary to peel the said polarizing film from a glass substrate etc. have. Since the polarizer is thin and the protective film is provided only in the single side | surface of a polarizer, the thickness of the whole is very thin in the single protective polarizing film provided with the adhesive layer using a thin polarizer. Therefore, there exists a problem that the single protection polarizing film provided with the adhesive layer which used the conventional thin polarizer is easy to be broken when peeling from a glass substrate.

An object of this invention is to provide the single protection polarizing film provided with the adhesive layer which can suppress the defect by a nano slit, and is excellent in antistatic function and rework property, and the adhesive layer which has this adhesive layer. .

Moreover, an object of this invention is to provide the image display apparatus which has a single protection polarizing film provided with the said adhesive layer, and its continuous manufacturing method.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining, the present inventors discovered that the said subject can be solved by the following adhesive layer, and came to this invention.

That is, this invention is an adhesive layer containing a (meth) acrylic-type polymer as a base polymer,

The (meth) acrylic polymer contains, as monomer units, an alkyl (meth) acrylate having 2 to 12 carbon atoms of an alkyl group, and methyl (meth) acrylate,

The said adhesive layer is related with the adhesive layer characterized by satisfy | filling following formula (1).

Abs (a): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the C-O-C bond of methyl (meth) acrylate

Abs (b): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the C-O-C bond of the alkyl (meth) acrylate

Abs (c): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the lowest absorbance in the range of 800 ~ 900cm ^-1

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining about the relationship between the material of the adhesive layer provided in a polarizing film, the number of generation | occurrence | production of a nano slit, an antistatic function, and rework property, the adhesive layer which satisfy | fills said Formula (1) is It was found that the defect caused by the nano slit can be effectively suppressed and that the antistatic function and the reworkability are excellent. In detail, an adhesive layer can be highly elasticized by using methyl (meth) acrylate as a copolymerization monomer of the (meth) acrylic-type polymer which is a material of an adhesive layer. This makes it difficult to generate nano slits in the polarizer. And the more content of methyl (meth) acrylate is, the higher the elasticity of the pressure-sensitive adhesive layer, the more likely that nano slits are more likely to occur in the polarizer. However, in order for methyl (meth) acrylate to raise the cohesion force of a (meth) acrylic-type polymer, the more content of methyl (meth) acrylate is, the higher the adhesive force of an adhesive layer becomes and the rework property deteriorates. In addition, since there is more content of methyl (meth) acrylate, since the movement of an antistatic agent is suppressed by the steric hindrance of a (meth) acrylic-type polymer, the antistatic function of an adhesive layer falls. As mentioned above, the present inventors think that content of the methyl (meth) acrylate which is a copolymerization monomer of a (meth) acrylic-type polymer has a big influence on the generation number of a nano slit, the antistatic function of an adhesive layer, and rework property. It was. And the present inventors derived from the antisymmetric stretching vibration of the COC bond of the alkyl (meth) acrylate of 2-12 carbon atoms of an alkyl group in IR measurement by the Attenuated Total Reflection (ATR method) of an adhesive layer. The pressure-sensitive adhesive layer having a peak absorbance of 0.30 or more and less than 0.48 derived from the antisymmetric stretching vibration of the methyl (meth) acrylate to the peak absorbance can effectively suppress defects caused by the nano slit, and further excellent antistatic function And the reworkability were found to be compatible.

It is preferable that the said adhesive layer contains an alkali metal salt, and it is preferable to contain a rework improvement agent further.

Moreover, it is preferable that the said adhesive layer is 25 micrometers or less in thickness.

Moreover, this invention relates to the single protection polarizing film which has a protective film only in the single side | surface of a polarizer, and the single protection polarizing film provided with the adhesive layer which has the said adhesive layer in the polarizer side of the said single protection polarizing film directly or through a coating layer. .

It is preferable that the said polarizer is 12 micrometers or less in thickness.

Moreover, the said polarizer contains polyvinyl alcohol-type resin, and the optical characteristic represented by the single transmittance T and the polarization degree P is a following formula.

P>-(10 ^{0.929T-42.4-1} ) × 100 (where T <42.3) or

It is preferable that it is configured to satisfy the condition of P≥99.9 (where T≥42.3).

Moreover, it is preferable that the said polarizer contains 25 weight% or less of boric acid with respect to the polarizer whole quantity.

A separator can be provided in the adhesive layer of the single protection polarizing film provided with the said adhesive layer. The single protection polarizing film provided with the adhesive layer in which the separator was provided can be used as a winding object.

Moreover, this invention relates to the image display apparatus which has a single protection polarizing film provided with the said adhesive layer.

In addition, the present invention provides a single protective polarizing film having the pressure sensitive adhesive layer transported from the wound body of the single protective polarizing film having the pressure sensitive adhesive layer and conveyed by the separator through the pressure sensitive adhesive layer of the image display panel. A continuous manufacturing method of an image display device including a step of continuously bonding to a surface.

Since the single protection polarizing film provided with the adhesive layer of this invention has the said adhesive layer, generation | occurrence | production of a nano slit can be suppressed effectively, without providing a coating layer. Moreover, since the process of providing a coating layer can abbreviate | omit the single protection polarizing film provided with the adhesive layer of this invention, productivity can be improved compared with the conventional thing which provided the coating layer. Moreover, since the single protection polarizing film provided with the adhesive layer of this invention is excellent in antistatic function, color fallout is hard to generate | occur | produce. Moreover, since the single protection polarizing film provided with the adhesive layer of this invention is excellent in rework property, even if a thin polarizer is used, it can peel without breaking the said polarizing film from a glass substrate etc.

BRIEF DESCRIPTION OF THE DRAWINGS It is an example of schematic sectional drawing of the single protection polarizing film provided with the adhesive layer of this invention.
2 is an example of the conceptual diagram which contrasts the nano slit and through crack which generate | occur | produce in a polarizer.
It is a schematic diagram explaining the evaluation item about the nano slit of an Example and a comparative example.
It is an example of the photograph which shows the crack which arises by the nano slit concerning evaluation of an Example and a comparative example.
5 is an example of schematic sectional drawing of the continuous manufacturing system of an image display apparatus.

The partial protection polarizing film provided with the adhesive layer of this invention is demonstrated below, referring FIG. The single protective polarizing film 11 provided with the adhesive layer of this invention has the single protective polarizing film 10 and the adhesive layer 4, for example. The adhesive layer 4 is an adhesive layer which concerns on this invention. The single protection polarizing film 10 has the protective film 2 only in the single side | surface of the polarizer 1, as shown in FIG. The polarizer 1 and the protective film 2 are laminated | stacked through the adhesive bond layer 3 (other intervening layers, such as an adhesive layer and a undercoat layer (primer layer)). In addition, although not shown in figure, the single protection polarizing film 10 can provide an easily bonding layer to the protective film 2, or can perform an activation process, and can laminate | stack the said easily bonding layer and an adhesive bond layer. In addition, although not shown, the protective film 2 can be provided in multiple numbers. The some protective film 2 can be laminated | stacked by the adhesive bond layer 3 (other intervening layers, such as an adhesive layer and a undercoat layer (primer layer)).

In addition, as shown in FIG. 1, the adhesive layer 4 in the single protective polarizing film 11 provided with the adhesive layer of this invention is the side of the polarizer 1 of the single protective polarizing film 10. As shown in FIG. Prepared. In addition, although not shown, you may provide a coating layer between the polarizer 1 and the adhesive layer 4. The coating layer is not particularly limited, and for example, a known transparent layer described in Japanese Patent No. 6077618 and the like can be applied. Moreover, the separator 5 can be provided in the adhesive layer 4 of the single protection polarizing film 11 provided with the adhesive layer of this invention, and the surface protection film 6 can be provided in the opposite side. In the single protection polarizing film 11 provided with the adhesive layer of FIG. 1, the case where both the separator 5 and the surface protection film 6 are provided is shown. The single-protective polarizing film 11 (in addition, having the surface protective film 6) provided with the pressure-sensitive adhesive layer having at least the separator 5 can be used as a wound body, for example, as a wound body The method of bonding the single protective polarizing film 11 provided with the pressure-sensitive adhesive layer conveyed by the separator 5 to the surface of the image display panel through the pressure-sensitive adhesive layer 4 (hereinafter referred to as "roll-to-panel method") Representatively, it is advantageous to the application to Japanese Patent No. 4604604. The single protection polarizing film provided with the adhesive layer of FIG. 1 is used preferably from a viewpoint of curvature suppression of the display panel after bonding, suppression of generation of a nano slit, and the like.

FIG. 2 is a conceptual diagram comparing nano slit a and through crack b generated in a polarizer. FIG. 2A shows nanoslit a generated in the polarizer 1, and through crack b generated in the polarizer 1 is shown in FIG. 2B. Although the nano slit a is generated by mechanical impact and partially generated in the absorption axis direction of the polarizer 1, the original occurrence of the nano slit a cannot be confirmed, but under a thermal environment (for example, 80 ° C. or 60 ° C.). C, 90% RH) can be confirmed by expansion in the width direction. On the other hand, it can be considered that the nano slit a has no progression extending in the absorption axis direction of the polarizer. In addition, it is thought that the said nano slit a arises irrespective of the size of a polarizing film. The nano slits a may be generated singly or may be adjacently generated. On the other hand, the through crack b is generated by thermal shock (for example, a heat shock test). The through crack has progression extending in the absorption axis direction of the polarizer in which the crack has occurred. When the through crack b occurs, the peripheral stress is released, so that the through crack does not occur 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, even more preferably 7 from the viewpoint of suppressing the occurrence of thinning and through cracks. Μm or less, particularly preferably 6 µm or less. On the other hand, it is preferable that the thickness of a polarizer is 1 micrometer or more. Such a thin polarizer has little thickness nonuniformity, is excellent in visibility, and is small in dimensional change, and is excellent in durability to thermal shock.

The thing using polyvinyl alcohol-type resin is used for a polarizer. As a polarizer, a biaxial substance of iodine or a dichroic dye is adsorbed to hydrophilic polymer films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene vinyl acetate copolymerized partial saponified films. And polyene oriented films such as stretched, dehydrated polyvinyl alcohol and dehydrochloric acid polyvinyl chloride. Among these, the polarizer which consists of dichroic substances, such as a polyvinyl alcohol-type film and iodine, is suitable.

The polarizer which uniaxially stretched the polyvinyl alcohol-type film by iodine, can be produced by dyeing polyvinyl alcohol by immersing it in the aqueous solution of iodine, and extending | stretching 3 to 7 times the original length, for example. Boric acid, zinc sulfate, zinc chloride, etc. may be included as needed, and it can also be immersed in aqueous solutions, such as potassium iodide. If necessary, the polyvinyl alcohol-based film may be dipped in water and washed with water before dyeing. In addition to washing the polyvinyl alcohol-based film with water, the contamination of the polyvinyl alcohol-based film with the anti-blocking agent can be washed, and the polyvinyl alcohol-based film is swollen to prevent irregularities such as staining. Stretching may be performed after dyeing with iodine, or may be performed while dyeing, or may be dyed with iodine after stretching. It can extend | stretch also in aqueous solution, such as boric acid and potassium iodide, or a water bath.

It is preferable that a polarizer contains boric acid from the point of extending | stretching stability or optical durability. Moreover, it is preferable that boric acid content contained in a polarizer is 25 weight% or less with respect to polarizer whole quantity from a viewpoint of suppression of generation | occurrence | production suppression and expansion suppression of a penetration crack and nanoslit, Furthermore, it is preferable that it is 20 weight% or less, Furthermore, 18 weight% Hereinafter, it is preferable that it is 16 weight% or less further. When the boric acid content contained in a polarizer exceeds 25 weight%, even if the thickness of a polarizer is made thin (for example, 12 micrometers or less in thickness), since shrinkage stress of a polarizer becomes high and penetration cracks tend to arise, it is unpreferable. On the other hand, it is preferable that boric acid content with respect to polarizer whole quantity is 10 weight% or more from a viewpoint of extending | stretching stability and optical durability of a polarizer, and also it is 12 weight% or more.

As a thin polarizer, typically

Japanese Patent No. 4751486,

Japanese Patent No.4751481,

Japanese Patent No. 4815544,

Japanese Patent No. 5048120,

Japanese Patent No.5587517,

International Publication No. 2014/077599,

International Publication No. 2014/077636,

The thin polarizer obtained from the thin polarizer described in etc. or the manufacturing method as described in these is mentioned.

The said polarizer has the optical characteristic represented by the single transmittance T and the polarization degree P, and is a following formula

P>-(10 ^{0.929T-42.4-1} ) × 100 (where T <42.3) or

It is preferably configured to satisfy the condition of P≥99.9 (where T≥42.3). The polarizer comprised so that the said condition is satisfy | filled has the performance calculated | required uniquely as the display for liquid crystal TVs using a large display element. Specifically, the contrast ratio is at least 1000: 1 and at least 500 cd / m 2. As another use, it is joined to the visual recognition side of an organic electroluminescence display, for example.

On the other hand, since the polarizer configured to satisfy the above conditions has a high orientation of the constituent polymer (for example, polyvinyl alcohol-based molecule), the polarizer is thin (for example, 12 µm or less in thickness) and the absorption axis of the polarizer. The tensile stress at break in the direction orthogonal to the direction becomes significantly smaller. As a result, for example, when exposed to the mechanical impact exceeding the tensile stress at break in the manufacturing process of the polarizing film, the possibility that the nano slit occurs in the absorption axis direction of the polarizer is very high. Therefore, this invention is especially suitable for the single protection polarizing film which employ | adopted the said polarizer (or the single protection polarizing film provided with the adhesive layer using the same).

As said thin polarizer, in the manufacturing method which includes the process of extending | stretching in the state of a laminated body, and the process of dyeing, it is extended by high magnification, and can improve polarization performance, Unexamined-Japanese-Patent No.4751486, Japanese Patent No.4751481 It is preferable that it is obtained by the manufacturing method including the process of extending | stretching in boric-acid aqueous solution as described in Unexamined-Japanese-Patent No. 4815544, Especially extending | stretching in boric-acid aqueous solution as described in Unexamined-Japanese-Patent No.4751481 and Unexamined-Japanese-Patent No.4815544. It is preferable that it is obtained by the manufacturing method including the process of extending | stretching previously auxiliary auxiliary. These thin polarizers can be obtained by the manufacturing method including the process of extending | stretching and dyeing a polyvinyl alcohol-type resin (henceforth a PVA-type resin) layer, and the extending | stretching resin base material in the state of a laminated body. If it is this manufacturing method, even if a PVA system resin layer is thin, it can be extended | stretched without problems, such as a fracture by extending | stretching, by being supported by the resin base material for extending | stretching.

<Protective film>

As a material which comprises the said protective film, what is excellent in transparency, mechanical strength, heat stability, moisture barrier property, isotropy, etc. is preferable. For example, polyester polymers such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers such as diacetyl cellulose and triacetyl cellulose, acrylic polymers such as polymethyl methacrylate, polystyrene and acrylonitrile styrene copolymer ( Styrene-type polymers, such as AS resin), a polycarbonate-type polymer, etc. are mentioned. Further, polyethylene, polypropylene, polyolefins having a cyclo or norbornene structure, polyolefin polymers such as ethylene propylene copolymers, amide polymers such as vinyl chloride polymers, nylon and aromatic polyamides, imide polymers, and sulfones Polymer, polyether sulfone type polymer, polyether ether ketone type polymer, polyphenylene sulfide type polymer, vinyl alcohol type polymer, vinylidene chloride type polymer, vinyl butyral type polymer, arylate type polymer, polyoxymethylene type polymer, epoxy A system polymer, the blend of the said polymer, etc. are mentioned as an example of the polymer which forms the said protective film.

In addition, one or more types of arbitrary appropriate additives may be contained in the protective film. As an additive, a ultraviolet absorber, antioxidant, a lubricating agent, a plasticizer, a mold release agent, a coloring inhibitor, a flame retardant, a nucleating agent, an antistatic agent, a pigment, a coloring agent, etc. are mentioned, for example. Content of the said thermoplastic resin in a protective film becomes like this. Preferably it is 50-100 weight%, More preferably, it is 50-99 weight%, More preferably, it is 60-98 weight%, Especially preferably, it is 70-97 weight%. When content of the said thermoplastic resin in a protective film is 50 weight% or less, there exists a possibility that the high transparency etc. which a thermoplastic resin originally has may not fully be expressed.

As the said protective film, a retardation film, a brightness improving film, a diffusion film, etc. can also be used. As a phase difference film, what has a phase difference whose front phase difference is 40 nm or more and / or thickness direction phase difference is 80 nm or more is mentioned. The front phase difference is usually in a range of 40 to 200 nm, and the thickness direction phase difference is usually controlled in a range of 80 to 300 nm. When using a retardation film as a protective film, since the said retardation film also functions as a polarizer protective film, thickness can be aimed at.

As a retardation film, the birefringent film formed by carrying out uniaxial or biaxial stretching process of a thermoplastic resin film is mentioned. The temperature of the said drawing, a draw ratio, etc. are suitably set with a phase difference value, the material of a film, thickness.

Although the thickness of a protective film can be suitably determined, it is generally 1-500 micrometers from the points of workability, thinness, etc., such as strength and handleability. 1-300 micrometers is especially preferable, 5-200 micrometers is more preferable, Furthermore, it is especially suitable when it is 5-150 micrometers, especially when it is thin of 5-80 micrometers.

On the surface which does not adhere the polarizer of the said protective film, functional layers, such as a hard coat layer, an antireflection layer, a sticking prevention layer, a diffusion layer, an antiglare layer, can be provided. The functional layers such as the hard coating layer, the antireflection layer, the anti-sticking layer, the diffusion layer, and the antiglare layer can be provided on the protective film itself, and can be provided separately from the protective film.

<Intervention level>

The said protective film and a polarizer are laminated | stacked through intervening layers, such as an adhesive bond layer, an adhesive layer, and an undercoat layer (primer layer). At this time, it is preferable to laminate both without an air gap by an intervening layer. The protective film and the polarizer are preferably laminated through an adhesive layer.

The adhesive layer is formed by an adhesive. The kind of adhesive is not specifically limited, Various things can be used. The adhesive layer is not particularly limited as long as it is optically transparent. Examples of the adhesive include various types of adhesives such as water-based, solvent-based, hot-melt, and active energy ray-curable, but aqueous adhesives or active energy ray-curable adhesives are suitable.

As an aqueous adhesive agent, an isocyanate adhesive, a polyvinyl alcohol adhesive, a gelatin adhesive, a vinyl latex type, an aqueous polyester, etc. can be illustrated. An aqueous adhesive is normally used as an adhesive which consists of aqueous solution, and usually contains 0.5 to 60 weight% of solid content.

An active energy ray hardening-type adhesive agent is an adhesive agent which hardening advances by active energy rays, such as an electron beam and an ultraviolet-ray (radical hardening type, a cation hardening type), and can be used, for example in the aspect of an electron beam hardening type and an ultraviolet curable type. As an active energy ray hardening-type adhesive agent, an optical radical hardening type adhesive agent can be used, for example. When using the radical photocurable active energy ray hardening-type adhesive agent as an ultraviolet curable type | mold, the said adhesive agent contains a radically polymerizable compound and a photoinitiator.

The coating method of an adhesive agent is suitably selected according to the viscosity of the adhesive agent and the thickness made into the objective. As an example of a coating system, a reverse coater, a gravure coater (direct, reverse or offset), a bar reverse coater, a roll coater, a die coater, a bar coater, a rod coater etc. are mentioned, for example. In addition, methods, such as a dipping method, can be used suitably for coating.

In addition, when applying an aqueous adhesive etc., it is preferable to perform coating of the said adhesive so that the thickness of the adhesive bond layer finally formed may be 30-300 nm. The thickness of the said adhesive bond layer becomes like this. More preferably, it is 60-250 nm. On the other hand, when using an active energy ray hardening-type adhesive agent, it is preferable to carry out so that the thickness of the said adhesive bond layer may be 0.1-200 micrometers. More preferably, it is 0.5-50 micrometers, More preferably, it is 0.5-10 micrometers.

In addition, in lamination | stacking of a polarizer and a protective film, an easily bonding layer can be provided between a protective film and an adhesive bond layer. An easily bonding layer can be formed with various resin which has a polyester skeleton, a polyether skeleton, a polycarbonate skeleton, a polyurethane skeleton, a silicone type, a polyamide skeleton, a polyimide skeleton, a polyvinyl alcohol skeleton, etc., for example. have. These polymer resins can be used individually by 1 type or in combination of 2 or more type. Moreover, you may add another additive to formation of an easily bonding layer. More specifically, you may use stabilizers, such as a tackifier, a ultraviolet absorber, antioxidant, and a heat resistant stabilizer.

The easily bonding layer is usually provided in advance in the protective film, and the easily bonding layer side and the polarizer of the protective film are laminated by the adhesive layer. Formation of an easily bonding layer is performed by coating and drying the formation material of an easily bonding layer on a protective film by a well-known technique. The formation material of an easily bonding layer is normally adjusted as a solution diluted to an appropriate density | concentration in consideration of the thickness after drying, the smoothness of coating, etc. The thickness after drying of an easily bonding layer becomes like this. Preferably it is 0.01-5 micrometers, More preferably, it is 0.02-2 micrometers, More preferably, it is 0.05-1 micrometer. In addition, although the easily bonding layer can be provided in multiple layers, it is preferable to make it the total thickness of an easily bonding layer become the said range also in this case.

An adhesive layer is formed with an adhesive. Various adhesives can be used as an adhesive, For example, a rubber adhesive, an acrylic adhesive, a silicone adhesive, a urethane type adhesive, a vinyl alkyl ether type adhesive, a polyvinylpyrrolidone type adhesive, a polyacrylamide type adhesive, a cellulose type adhesive etc. are mentioned. have. An adhesive base polymer is selected according to the kind of said adhesive. Among the pressure-sensitive adhesives, acrylic pressure-sensitive adhesives are preferably used in that they are excellent in optical transparency, exhibit moderate wettability, cohesiveness, and adhesive adhesive properties, and are excellent in weather resistance, heat resistance, and the like.

The undercoat 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 the material exhibits a certain strong adhesion to both the base film and the polyvinyl alcohol-based resin layer. For example, thermoplastic resins excellent in transparency, thermal stability, stretchability and the like are used. As a thermoplastic resin, acrylic resin, polyolefin resin, polyester resin, polyvinyl alcohol resin, or a mixture thereof is mentioned, for example.

<Adhesive layer>

The adhesive layer of this invention provided in the said piece protection polarizing film contains a (meth) acrylic-type polymer as a base polymer. The (meth) acrylic polymer contains, as monomer units, an alkyl (meth) acrylate having 2 to 12 carbon atoms of an alkyl group, and methyl (meth) acrylate. And the adhesive layer of this invention is characterized by satisfy | filling following formula (1). In addition, the alkyl group of the said alkyl (meth) acrylate may have various substituents. In that case, the carbon number of the said alkyl group does not contain the carbon number of the said substituent.

Abs (a): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the C-O-C bond of methyl (meth) acrylate

Abs (b): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the C-O-C bond of the alkyl (meth) acrylate

Abs (c): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the lowest absorbance in the range of 800 ~ 900cm ^-1

The peak resulting from the antisymmetric stretching vibration of the COC bond of methyl (meth) acrylate appears in the range of 1100-1130 cm ^-1 . In addition, the peak derived from the antisymmetric stretching vibration of the COC bond of the said alkyl (meth) acrylate appears in the range of 1150-1260 cm <^-1> .

Abs (c) is the lowest absorbance in the range of 800 to 900 cm ⁻¹ , that is, the absorbance of the base line.

When the IR parameter [(Abs (a) -Abs (c)) / (Abs (b) -Abs (c))] of the said Formula (1) is outside the said numerical range, the crack suppression function of a pressure-sensitive adhesive layer, rework The characteristics of either the castle or the antistatic function are deteriorated.

An acrylic adhesive is used for formation of the adhesive layer of this invention. The acrylic pressure sensitive adhesive is excellent in optical transparency, exhibits moderate wettability, cohesiveness, and adhesive adhesion characteristics, and is excellent in weather resistance, heat resistance, and the like, and therefore is suitable as a material for forming an adhesive layer.

As said acryl-type adhesive, the (meth) acrylic-type polymer containing the monomer unit of the alkyl (meth) acrylate whose carbon number of an alkyl group is 2-12 as a main frame, and the monomer unit of methyl (meth) acrylate is used as a base polymer. Use what you do. The said (meth) acrylic-type polymer may contain the monomer unit of the (meth) acrylate of that excepting the above in the range which does not impair the effect of this invention. In addition, (meth) acrylate means acrylate and / or methacrylate, and is the same meaning as the (meth) of this invention.

Specific examples of the alkyl (meth) acrylate having 2 to 12 carbon atoms for the alkyl group include ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. Isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl ( Meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, and dodecyl (meth) acrylate. Substituted alkyl having 2 to 12 carbon atoms in alkyl groups such as carboxyalkyl (meth) acrylate, hydroxyalkyl (meth) acrylate, aminoalkyl (meth) acrylate, and alkoxyalkyl (meth) acrylate, which will be described later. (Meth) acrylate is mentioned. These can be used individually or in combination. Among them, it is preferable to use at least one selected from ethyl acrylate, propyl acrylate, n-butyl acrylate, n-pentyl methacrylate, n-hexyl acrylate, and 2-ethylhexyl acrylate, More preferably, n-butylacrylate is used. In addition, when using 2 or more types of said alkyl (meth) acrylates, Abs (b) in said Formula (1) is a sum total of each peak absorbance (it may be represented by one peak). .

In order to obtain the adhesive layer which satisfy | fills the said Formula (1), it is preferable that the said (meth) acrylic-type polymer contains 70-99 weight% of alkyl (meth) acrylates whose carbon number of the said alkyl group is 2-12 as a monomeric unit. Preferably, it is 75-98 weight%, More preferably, it is 80-96 weight%. Moreover, it is preferable that the said (meth) acrylic-type polymer contains 1-15 weight% of methyl (meth) acrylate as a monomeric unit, More preferably, it is 2-12 weight%, More preferably, it is 4-10 % By weight.

In the said (meth) acrylic-type polymer, one or more types of various monomers can be introduce | transduced by copolymerization in order to improve adhesiveness, heat resistance, etc. As a specific example of such a copolymerization monomer, a carboxyl group containing monomer, a hydroxyl group containing monomer, a nitrogen containing monomer, an aromatic group containing monomer, etc. are mentioned.

As a carboxyl group-containing monomer, acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, a crotonic acid, etc. are mentioned, for example. These can be used individually or in combination.

As a hydroxyl-containing monomer, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8 -Hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) -methyl acrylate, etc. are mentioned. have. These can be used individually or in combination.

As the nitrogen-containing monomer, for example, a vinyl monomer having a lactam ring (for example, a vinylpyrrolidone monomer such as N-vinylpyrrolidone, methylvinylpyrrolidone, β-lactam ring, δ-lactam ring and vinyl lactam monomers having lactam rings such as ε-lactam ring; Maleimide monomers such as maleimide, N-cyclohexyl maleimide, and N-phenylmaleimide; (Meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-hexyl (meth) acrylamide, N-methyl (meth) acrylamide, N-butyl (N-substituted) amide monomers, such as (meth) acrylamide, N-butyl (meth) acrylamide, N-methylol (meth) acrylamide, and N-methylol propane (meth) acrylamide; Aminoethyl (meth) acrylate, aminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, t-butylaminoethyl (meth) acrylate, 3- (3-pyridylyl) propyl (meth) acrylate (Meth) acrylic-acid aminoalkyl type monomers, such as these; N- (meth) acryloyloxymethylene succinimide, N- (meth) acryloyl-6-oxyhexamethylene succinimide, N- (meth) acryloyl-8-oxyoctamethylene succinimide, etc. Succinimide monomers; Cyano (meth) acrylate monomers such as acrylonitrile and methacrylonitrile; Vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, N-vinylcarboxylic acid amides and the like. These can be used individually or in combination.

As an aromatic group containing monomer, benzyl (meth) acrylate, phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, etc. are mentioned, for example. These can be used individually or in combination.

Acid anhydride group-containing monomers such as maleic anhydride and itaconic anhydride; Caprolactone adducts of acrylic acid; Sulfonic acid groups such as styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidopropanesulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxynaphthalenesulfonic acid Containing monomers; Phosphoric acid group containing monomers, such as 2-hydroxyethyl acryloyl phosphate, etc. are mentioned. These can be used individually or in combination.

Furthermore, vinyl monomers, such as vinyl acetate, a vinyl propionate, styrene, (alpha) -methylstyrene, and N-vinyl caprolactam; Epoxy group-containing acrylic monomers such as glycidyl (meth) acrylate; Glycol-based acrylic ester monomers such as polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, methoxyethylene glycol (meth) acrylate, and methoxypolypropylene glycol (meth) acrylate; Acrylic ester ester monomers, such as (meth) acrylic acid tetrahydrofurfuryl, fluorine (meth) acrylate, silicone (meth) acrylate, and 2-methoxyethyl acrylate, can also be used. These can be used individually or in combination.

At least one polar monomer selected from the carboxyl group-containing monomer, the hydroxyl group-containing monomer, and the nitrogen-containing monomer is selected from the viewpoint of improving the cohesive force of the (meth) acrylic polymer to more effectively suppress the generation of the nano slit. It is preferable to introduce | transduce into the said (meth) acrylic-type polymer by copolymerization, More preferably, the said carboxyl group-containing monomer, the said hydroxyl-containing monomer, and the said nitrogen-containing monomer are introduce | transduced into the said (meth) acrylic-type polymer by copolymerization. As said carboxyl group-containing monomer, (meth) acrylic acid is preferable. As said hydroxyl-containing monomer, 1 or more types chosen from 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate are preferable. It is preferable that the said nitrogen-containing monomer is a vinyl monomer which has a lactam ring, More preferably, it is the said vinylpyrrolidone type monomer, More preferably, it is N-vinylpyrrolidone. By introducing the nitrogen-containing monomer into the (meth) acrylic polymer by copolymerization, generation of nano slits can be more effectively suppressed, and durability (peel resistance) of the pressure-sensitive adhesive layer at high temperature and / or high humidity can be suppressed. Can be improved.

It is preferable that the said (meth) acrylic-type polymer contains 0.01-2 weight% of the said carboxyl group-containing monomer as a monomer unit, More preferably, it is 0.05-1 weight%, More preferably, it is 0.1-0.3 weight%.

It is preferable that the said (meth) acrylic-type polymer contains 0.01-1 weight% of said hydroxyl group containing monomers as monomer unit, More preferably, it is 0.05-1 weight%, More preferably, it is 0.1-0.5 weight%.

It is preferable that the said (meth) acrylic-type polymer contains 0.1-5 weight% of said nitrogen containing monomers as a monomer unit, More preferably, it is 0.5-3 weight%, More preferably, it is 1.5-3 weight%.

The average molecular weight of the (meth) acrylic polymer is not particularly limited, but the weight average molecular weight is preferably about 500,000 to 2.5 million. The production of the (meth) acrylic polymer can be produced by various known methods, and for example, a radical polymerization method such as a bulk polymerization method, a solution polymerization method or a suspension polymerization method can be appropriately selected. As a radical polymerization initiator, various well-known thing of azo type and a peroxide type can be used. Reaction temperature is about 50-80 degreeC normally, and reaction time is 1 to 8 hours. Moreover, the solution polymerization method is preferable also in the said manufacturing method, and ethyl acetate, toluene, etc. are generally used as a solvent of a (meth) acrylic-type polymer.

A crosslinking agent can be mix | blended with the said adhesive. By a crosslinking agent, adhesiveness and durability can be improved, and reliability at high temperature and the maintenance of the shape of the adhesive itself can be aimed at. As a crosslinking agent, an isocyanate type, an epoxy type, a peroxide type, a metal chelate type, an oxazoline type, etc. can be used suitably. These crosslinking agents can be used 1 type or in combination of 2 or more types.

An isocyanate compound is used for an isocyanate type crosslinking agent. As an isocyanate compound, tolylene diisocyanate, chlorophenylenedi isocyanato, hexamethylene diisocyanato, tetramethylene diisocyanato, isophorone diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane di Isocyanate monomers, such as an isocyanate, Adduct type isocyanate compound which added these isocyanate monomers to trimethylol propane etc .; Isocyanurate, a biuret type compound, a urethane prepolymer type isocyanate etc. which addition-reacted well-known polyether polyol, polyester polyol, an acryl polyol, polybutadiene polyol, polyisoprene polyol, etc. are mentioned.

Although the said isocyanate type crosslinking agent may be used individually by 1 type, and may mix and use 2 or more types, the whole content consists of 0.01-2 weight part of said isocyanate type crosslinking agents with respect to 100 weight part of base polymers. It is preferable, it is more preferable to contain 0.02-2 weight part, and it is still more preferable to contain 0.05-1.5 weight part. It is possible to contain it appropriately in consideration of cohesion force, prevention of peeling in the durability test, and the like.

As the peroxide crosslinking agent, various peroxides are used. Examples of the peroxide include di (2-ethylhexyl) peroxydicarbonate, di (4-t-butylcyclohexyl) peroxydicarbonate, di-sec-butylperoxydicarbonate, and t-butylperoxy neode Decanoate, t-hexyl peroxy pivalate, t-butyl peroxy pivalate, dilauroyl peroxide, di-n-octanoyl peroxide, 1,1,3,3-tetramethylbutylperoxyisobutyrate And 1,1,3,3-tetramethylbutylperoxy2-ethylhexanoate, di (4-methylbenzoyl) peroxide, dibenzoylperoxide, t-butylperoxyisobutyrate and the like. Among these, di (4-t-butylcyclohexyl) peroxydicarbonate, dilauroyl peroxide, and dibenzoyl peroxide, which are particularly excellent in crosslinking reaction efficiency, are preferably used.

Although the said peroxide may be used individually by 1 type, and may mix and use 2 or more types, the total content is 0.01-2 weight part of said peroxides with respect to 100 weight part of base polymers, and contains 0.04-1.5 weight part It is preferable to make it, and it is more preferable to contain 0.05-1 weight part. It is suitably selected within this range for adjustment of workability, reworkability, crosslinking stability, peelability, and the like.

In addition, the said adhesive may contain a silane coupling agent. By using a silane coupling agent, durability can be improved. As a silane coupling agent, what has arbitrary appropriate functional groups can be used. Specifically, as a functional group, a vinyl group, an epoxy group, an amino group, a mercapto group, a (meth) acryloxy group, acetoacetyl group, an isocyanate group, a styryl group, a polysulfide group, etc. are mentioned, for example. Specifically, For example, vinyl group containing silane coupling agents, such as vinyl triethoxysilane, vinyl tripropoxy silane, vinyl triisopropoxy silane, and vinyl tributoxy silane; γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, etc. Epoxy group-containing silane coupling agent; γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) 3-aminopropylmethyldimethoxysilane, γ-triethoxysilyl Amino group-containing silane coupling agents such as -N- (1,3-dimethylbutylidene) propylamine and N-phenyl-γ-aminopropyltrimethoxysilane; mercapto group-containing silane coupling agents such as γ-mercaptopropylmethyldimethoxysilane; styryl group-containing silane coupling agents such as p-styryltrimethoxysilane; (meth) acryl group-containing silane coupling agents such as γ-acryloxypropyltrimethoxysilane and γ-methacryloxypropyltriethoxysilane; Isocyanate group-containing silane coupling agents such as 3-isocyanatepropyltriethoxysilane; Polysulfide group containing silane coupling agents, such as bis (triethoxy silylpropyl) tetrasulfide, etc. are mentioned.

Although the said silane coupling agent may be used independently and may be used in mixture of 2 or more types, 0.001-5 weight part of said silane coupling agents are preferable with respect to 100 weight part of base polymers, and 0.01- 1 weight part is preferable, Furthermore, 0.02-1 weight part is more preferable, Furthermore, 0.05-0.6 weight part is preferable.

Moreover, it is preferable that the said adhesive contains a rework improver from a viewpoint of improving rework property. The said rework improver is a chemical substance which has a polar group, is easy to interact with a glass interface, and is easy to segregate at a glass interface. As said rework improver, the diol which has alkylene oxy groups, such as EO and PO, the oligomer which has a perfluoroalkyl group, the polyether compound which has a reactive silyl group, etc. are mentioned, for example. As said polyether compound, what is disclosed by Unexamined-Japanese-Patent No. 2010-275522 can be used, for example.

As a polyether compound which has the said reactive silyl group, For example, MS polymer S203, S303, S810 by Kaneka Corporation; SILYL EST250, EST280; SAT10, SAT200, SAT220, SAT350, SAT400, EXCESTAR S2410, S2420 or S3430 manufactured by Asahi Glass Co., etc. may be mentioned.

The content of the rework enhancer is preferably 0.001 part by weight or more, more preferably 0.01 part by weight or more, still more preferably 0.1 part by weight or more, and preferably 10 parts by weight or less based on 100 parts by weight of the base polymer. More preferably, it is 5 weight part or less, More preferably, it is 2 weight part or less, More preferably, it is 1 weight part or less. When content of a rework improver is less than 0.001 weight part, the rework property of an adhesive layer becomes difficult to improve, and when it exceeds 10 weight part, there exists a tendency for the adhesive characteristic of an adhesive layer to fall.

Moreover, it is preferable that the said adhesive contains an antistatic agent. At the time of manufacture of a liquid crystal display device, when affixing the single protection polarizing film provided with an adhesive layer to a liquid crystal panel, although a release film is peeled from the adhesive layer of the single protection polarizing film provided with an adhesive layer, by peeling of the said release film Static electricity is generated. Moreover, when joining the single protection polarizing film provided with the adhesive layer to a liquid crystal panel, when a bonding miss arises, it is necessary to peel the said polarizing film, but static electricity generate | occur | produces by peeling of the said polarizing film. The generated static electricity affects the alignment of the liquid crystal inside the liquid crystal display device, resulting in a defect. In addition, display nonuniformity by static electricity may arise at the time of use of a liquid crystal display device. By adding an antistatic agent to an adhesive, an antistatic function is provided to the adhesive layer of the single protection polarizing film provided with an adhesive layer, and these problems can be prevented.

The antistatic agent is not particularly limited, and examples thereof include ionic compounds such as onium-anion salts and alkali metal salts. When an ionic compound is added, it can be considered that the antistatic function is expressed efficiently by bleeding out the ionic compound on the surface of the pressure-sensitive adhesive layer. On the other hand, when an ionic compound contacts a polarizer, optical characteristics, such as polarization degree, may fall. It is preferable to use an alkali metal salt especially from a viewpoint of suppressing the fall of the said optical characteristic.

As an alkali metal salt, the organic salt or inorganic salt of an alkali metal can be used. An alkali metal salt can be used individually by 1 type or in combination.

As an alkali metal ion which comprises the cation part of an alkali metal salt, each ion of lithium, sodium, and potassium is mentioned. Among these alkali metal ions, lithium ions are preferred.

The anion part of an alkali metal salt may be comprised with the organic substance, and may be comprised with the inorganic substance. As the anion portion constituting the organic salts, such as ^{_{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 - , etc., CO ₃ ^2- is used. In particular, the anion portion containing a fluorine atom is preferably used in that an ionic compound having good ion dissociation property is obtained. As the anion portion constituting the inorganic ^{salts, 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 - or the like is used. As the anion _{portion, (CF 3 SO 2) 2} N -, (C 2 F 5 SO 2) 2 N - a (alkylsulfonyl perfluoroalkyl), etc., and imide preferable, especially _{(CF 3 SO 2) 2 N} - (Trifluoromethanesulfonyl) imide represented by is preferable.

Specific examples of the organic salt of the alkali metal include sodium acetate, sodium alginate, sodium lignin sulfonate, sodium toluene sulfonate, LiCF ₃ SO ₃ , Li (CF ₃ SO ₂ ) ₂ N, 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 and the like, 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 and the like are preferred, 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 Fluorine containing lithium imide salts, such as these, are more preferable, and (perfluoroalkylsulfonyl) imide lithium salt is especially preferable.

Examples of inorganic salts of alkali metals include lithium perchlorate and lithium iodide.

As for content of the alkali metal salt in an adhesive, 0.001-5 weight part is preferable with respect to 100 weight part of base polymers. When the said alkali metal salt is less than 0.001 weight part, the effect of improving antistatic performance may not be enough. 0.01 weight part or more is preferable, and, as for the said alkali metal salt, it is preferable that it is 0.1 weight part or more. On the other hand, when the alkali metal salt is more than 5 parts by weight, durability may not be sufficient. As for the said alkali metal salt, 3 weight part or less is preferable.

As a method of forming an adhesive layer, after apply | coating the said adhesive to the separator etc. which carried out the peeling process, for example, after drying and removing a polymerization solvent etc. to form an adhesive layer, the polarizer side of a piece protection polarizing film (in the aspect of FIG. 1, a polarizer) ), Or the method of applying the pressure-sensitive adhesive, drying and removing the polymerization solvent and the like to form the pressure-sensitive adhesive layer on the polarizer side. In addition, at the time of application | coating of an adhesive, you may add a 1 or more types of solvent other than a polymerization solvent suitably.

Although the thickness of an adhesive layer is not specifically limited, From a viewpoint of effectively suppressing the defect by a nano slit, and achieving the outstanding antistatic function and rework property, Preferably it is 25 micrometers or less, More preferably, it is 23 micrometers or less, More Preferably it is 20 micrometers or less, More preferably, it is 10 micrometers or more, More preferably, it is 12 micrometers or more, More preferably, it is 15 micrometers or more.

As a peeling separator, a silicone peeling liner is used preferably. In the process of apply | coating and drying the adhesive of this invention on such a liner, and forming an adhesive layer, as a method of drying an adhesive, a suitable appropriate method can be employ | adopted according to the objective. Preferably, the method of overheating and drying the said coating film is used. The heat 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 making heating temperature into the said range, the adhesive which has the outstanding adhesive characteristic can be obtained.

As for a drying time, an appropriate time appropriately may be employ | adopted. The 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 are used as a formation method of an adhesive layer. Specifically, for example, by roll coating, kiss roll coating, gravure coating, reverse coating, roll brush, spray coating, dip roll coating, bar coating, knife coating, air knife coating, curtain coating, lip coating, die coater, etc. The extrusion coating method etc. are mentioned.

In the case where the pressure-sensitive adhesive layer is exposed, the pressure-sensitive adhesive layer may be protected by a sheet (separator) subjected to peeling treatment until it is provided for practical use.

As a constituent material of the separator, for example, plastic films such as polyethylene, polypropylene, polyethylene terephthalate, polyester film, porous materials such as paper, cloth, and nonwoven fabric, nets, foam sheets, metal foils, and laminates thereof Although a thin body etc. are mentioned, a plastic film is used suitably from the point which is excellent in surface smoothness.

It will not specifically limit, if it is a film which can protect the said adhesive layer as this plastic film, For example, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethyl pentene film, a polyvinyl chloride film, vinyl chloride A copolymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, an ethylene-vinyl acetate copolymer film, etc. are mentioned.

The thickness of the separator is usually 5 to 200 µm, preferably about 5 to 100 µm. The separator may be subjected to antistatic treatment such as release, antifouling treatment with a silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agent, silica powder, or the like, or coating, kneading or vapor deposition. In particular, the peelability from the pressure-sensitive adhesive layer can be further improved by appropriately performing a peeling treatment such as silicon treatment, long chain alkyl treatment, or fluorine treatment on the surface of the separator.

<Surface protection film>

A surface protection film can be provided in the single protection polarizing film provided with an adhesive layer. A surface protection film has a base film and an adhesive layer normally, and protects a polarizer through the said adhesive layer.

As a base film of a surface protection film, the film material which has isotropy or near isotropy is selected from a viewpoint of inspection property, manageability, etc .. Examples of the film material include polyester resins such as polyethylene terephthalate films, cellulose resins, acetate resins, polyether sulfone resins, polycarbonate resins, polyamide resins, polyimide resins, Transparent polymers, such as a polyolefin resin and an acrylic resin, are mentioned. Among these, polyester resin is preferable. The base film may be used as a laminate of one kind or two or more kinds of film materials, or may be a stretched product of the film. The thickness of a base film is generally 500 micrometers or less, Preferably it is 10-200 micrometers.

As an adhesive which forms the adhesive layer of a surface protection film, the adhesive which uses polymers, such as a (meth) acrylic-type polymer, a silicone type polymer, polyester, a polyurethane, a polyamide, a polyether, a fluorine type and a rubber type as a base polymer, is selected suitably, Can be used. From the viewpoint of transparency, weather resistance, heat resistance and the like, an acrylic pressure sensitive adhesive having an acrylic polymer as a base polymer is preferable. The thickness (dry film thickness) of an adhesive layer is determined according to the adhesive force required. Usually, it is about 1-100 micrometers, Preferably it is 5-50 micrometers.

Moreover, a peeling process layer can be provided in a surface protection film by low adhesive materials, such as a silicone process, a long chain alkyl process, and a fluorine process, on the opposite surface to which the adhesive layer in the base film was formed.

<Other optical layer>

The single protection polarizing film provided with the adhesive layer of this invention can be used as an optical film laminated | stacked with the other optical layer at the time of practical use. Although there is no limitation in particular about the optical layer, For example, in formation of a liquid crystal display device, such as a reflecting plate, a semi-transmissive plate, a retardation plate (including wavelength plates, such as 1/2 or a quarter), a visual compensation film The optical layer which may be used can use 1 layer, or 2 or more layers. In particular, a retardation plate is further laminated on a reflective polarizing film or a semi-transmissive polarizing film having a pressure-sensitive polarizing film having a pressure-sensitive adhesive layer of the present invention, a semi-transmissive polarizing film having a pressure-sensitive adhesive layer, or a polarizing film having a pressure-sensitive adhesive layer. The luminance improvement film is further laminated | stacked on the wide viewing angle polarizing film or the polarizing protective polarizing film provided with the adhesive layer which the visual compensation film is further laminated | stacked on the elliptical polarizing film or circular polarizing film which consists of an optical protective film, and the polarizing protective film provided with an adhesive layer. Polarizing films are preferred.

Although the optical film which laminated | stacked the said optical layer on the single protection polarizing film provided with an adhesive layer can also be formed also by the method of laminating | stacking separately one by one in the manufacturing process, such as a liquid crystal display device, what laminated | stacked previously and made into the optical film is There is an advantage that the stability of the quality, the assembly work, etc. are excellent, and the manufacturing process of a liquid crystal display device can be improved. Suitable lamination means such as an adhesive layer can be used for lamination. In the case of adhering the single protective polarizing film or the other optical film provided with the pressure-sensitive adhesive layer, these optical axes can be set to an appropriate placement angle in accordance with the desired phase difference characteristics and the like.

The single protection polarizing film or optical film provided with the adhesive layer of this invention can be used suitably for formation of various image display apparatuses, such as a liquid crystal display device and an organic electroluminescence display. Formation of a liquid crystal display device can be performed according to the prior art. That is, the liquid crystal display device is generally formed by appropriately assembling a component such as a polarizing protective film or an optical film having a liquid crystal cell and an adhesive layer, and an illumination system, if necessary, and embedding a driving circuit. In this invention, there is no restriction | limiting in particular except using the single protection polarizing film or optical film provided with the adhesive layer by this invention, and can follow conventionally. Also about a liquid crystal cell, although arbitrary types, such as IPS type and VA type, can be used, it is especially suitable for IPS type.

Suitable liquid crystal display devices, such as the liquid crystal display device which provided the single protection polarizing film or optical film with an adhesive layer in the one side or both sides of a liquid crystal cell, and the thing which used the backlight or the reflecting plate in the illumination system, can be formed. In that case, the single protection polarizing film or optical film provided with the adhesive layer by this invention can be provided in the one side or both sides of a liquid crystal cell. When providing the single protection polarizing film or optical film provided with an adhesive layer in both sides, they may be the same and may differ. In the formation of the liquid crystal display device, for example, a diffuser plate, an antiglare layer, an antireflection film, a protective plate, a prism array, a lens array sheet, a light diffuser plate, a backlight, or the like, at a suitable position, one or two layers, may be used. You can place more than that.

<Continuous Manufacturing Method of Image Display Device>

Said image display apparatus is a single-protective polarizing film provided with the said adhesive layer conveyed by the said separator by being fed from the winding body (roll) of the single protection polarizing film provided with the adhesive layer of this invention, and the said adhesive layer. It is preferable that it is manufactured by the continuous manufacturing method (roll-to-panel system) containing the process of continuously bonding to the surface of an image display panel through the. Since the single-protective polarizing film provided with the pressure-sensitive adhesive layer of the present invention is a very thin film, according to a method (also referred to as a "sheet-to-panel method") that is cut into a sheet shape (sheet cutting) and then bonded one by one to an image display panel. The handling at the time of conveyance of a sheet | seat and the bonding to a display panel is difficult, and in such a process, the single protection polarizing film (sheet) with an adhesive layer may receive a big mechanical shock (for example, bending by adsorption). Becomes higher. In order to reduce such a risk, the countermeasure, such as using a thick surface protection film whose thickness of a base film is 50 micrometers or more, for example is required separately. On the other hand, according to the roll-to-panel system, the single protection polarizing film provided with an adhesive layer is stably conveyed from a roll to an image display panel by a continuous separator, without being cut | disconnected (sheet cutting | disconnection) in a sheet form, and is an image as it is. Since it is bonded to a display panel, the said risk can be reduced significantly without using a thick surface protection film. As a result, the mechanical impact can be alleviated by the pressure-sensitive adhesive layer controlled so that the film thickness and the storage modulus satisfy a predetermined relational expression, and the image display panel can be produced at a high speed continuously in which the generation of nano slits is effectively suppressed.

5 is a schematic diagram illustrating an example of a continuous manufacturing system of a liquid crystal display device employing a roll-to-panel method. As shown in FIG. 5, the continuous manufacturing system 100 of a liquid crystal display device has a series of conveyance part X which conveys liquid crystal display panel P, the 1st polarizing film supply part 101a, and the 1st bonding part ( 201a), a second polarizing film supply portion 101b, and a second bonding portion 201b. Moreover, as a winding body (2nd roll) 20b of the winding protection body (1st roll) 20a of the single protection polarizing film provided with a 1st adhesive layer, and the single protection polarizing film provided with a 2nd adhesive layer, it was length. It has an absorption axis in the direction, and uses the thing of the aspect of FIG.

(Return)

The conveyance part X conveys liquid crystal display panel P. FIG. The conveyance part X is comprised by having several conveyance rollers, an adsorption plate, etc. The conveyance part X changes the arrangement | positioning relationship of the long side and short side of liquid crystal display panel P with respect to the conveyance direction of liquid crystal display panel P between 1st bonding part 201a and 2nd bonding part 201b. An arrangement switching unit (eg, horizontally rotating the liquid crystal display panel P by 90 °) 300 is included. Thereby, the single protective polarizing film 21a provided with the 1st adhesive layer and the single protective polarizing film 21b provided with the 2nd adhesive layer with respect to liquid crystal display panel P can be bonded by cross nicol relationship. .

(1st polarizing film supply part)

The 1st polarizing film supply part 101a is fed out from the 1st roll 20a, and is the single protection polarizing film (with surface protection film) 21a provided with the 1st adhesive layer conveyed by the separator 5a. Is continuously supplied to the first bonding portion 201a. The 1st polarizing film supply part 101a is the 1st feed part 151a, the 1st cut part 152a, the 1st peeling part 153a, the 1st winding part 154a, and the some conveyance roller part, a dancer roll. And an accumulating unit.

The 1st drawing part 151a has the drawing | feeding shaft in which the 1st roll 20a is provided, and the single protection polarizing film 21a provided with the strip | belt-shaped adhesive layer in which the separator 5a was provided from the 1st roll 20a. To help.

The 1st cutting part 152a has cutting means and adsorption means, such as a cutter and a laser apparatus. The 1st cut part 152a cut | disconnects the piece protection polarizing film 21a provided with the strip | belt-shaped 1st adhesive layer in the width direction, leaving the separator 5a. However, as the 1st roll 20a, the piece protection polarizing film 21a provided with the strip | belt-shaped adhesive layer in which the some cut line was formed in the width direction by predetermined length was laminated | stacked on the separator 5a (cutting) When the optical film roll with a line | wire formed) is used, the 1st cut part 152a becomes unnecessary (it is the same also about the 2nd cut part 152b mentioned later).

The 1st peeling part 153a peels the piece protection polarizing film 21a provided with the 1st adhesive layer from the separator 5a by returning the separator 5a inward. As the 1st peeling part 153a, a wedge-shaped member, a roller, etc. are mentioned.

The 1st winding-up part 154a winds up the separator 5a in which the single protection polarizing film 21a with a 1st adhesive layer peeled. The 1st winding-up part 154a has the winding shaft in which the roll for winding up the separator 5a is provided.

(First junction)

The 1st bonding part 201a is the single protection polarizing film 21a provided with the 1st adhesive layer peeled by the 1st peeling part 153a in liquid crystal display panel P conveyed by the conveyance part X. FIG. Is continuously bonded through the adhesive layer of the single protection polarizing film 21a provided with the 1st adhesive layer (1st bonding process). The 1st bonding part 81 has a pair of bonding rollers, and at least one of the bonding rollers is comprised by a drive roller.

(2nd polarizing film supply part)

The 2nd polarizing film supply part 101b is pulled from the 2nd roll 20b, and the single protection polarizing film (with surface protection film) 21b provided with the 2nd adhesive layer conveyed by the separator 5b. Is continuously supplied to the second bonding portion 201b. The 2nd polarizing film supply part 101b is the 2nd drawing part 151b, the 2nd cut part 152b, the 2nd peeling part 153b, the 2nd winding part 154b, and the some conveyance roller part, dancer roll. And an accumulating unit. Moreover, the 2nd drawing part 151b, the 2nd cut part 152b, the 2nd peeling part 153b, and the 2nd winding part 154b are the 1st drawing part 151a, the 1st cutting part 152a, respectively. It has a structure and a function similar to the 1st peeling part 153a and the 1st winding-up part 154a.

(Second junction)

The 2nd bonding part 201b is the single protection polarizing film 21b provided with the 2nd adhesive layer peeled by the 2nd peeling part 153b in liquid crystal display panel P conveyed by the conveyance part X. FIG. Is continuously bonded through the adhesive layer of the single protection polarizing film 21b provided with the 2nd adhesive layer (2nd bonding process). The 2nd bonding part 201b has a pair of bonding rollers, and at least one of the bonding rollers is comprised by a drive roller.

Example

Although an Example is given to this invention below, this invention is not limited to the Example shown below. In addition, all the parts and% in each case are a basis of weight. The room temperature standing conditions which are not specifically defined below are all 23 degreeC 65% RH.

<Production of Single Protection Polarizing Film>

(Production of polarizer)

0.75% water absorption, amorphous isophthalic acid copolymerized polyethylene terephthalate (IPA copolymerized PET) film (thickness: 100 μm) at Tg75 ° C. was subjected to corona treatment on one side of the substrate and polyvinyl alcohol (polymerization degree 4200). , Saponification degree 99.2 mol%) and acetacetyl modified PVA (polymerization degree 1200, acetacetyl modification degree 4.6%, saponification degree 99.0 mol% or more, Nippon Kose Kagaku Kogyo Co., Ltd. make, brand name "Gosepymer Z200") 9: 1 The aqueous solution contained at ratio of was apply | coated and dried at 25 degreeC, the PVA system resin layer of 11 micrometers in thickness was formed, and the laminated body was produced.

The obtained laminated body was uniaxially stretched by the free end part by 2.0 times in the longitudinal direction (length direction) between the rolls from which a circumferential speed differs in 120 degreeC oven (air auxiliary stretching process).

Subsequently, the laminate was immersed in an insolubilization 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. (insolubilization treatment).

Subsequently, it was immersed in the dyeing bath of 30 degreeC of liquid temperature, adjusting iodine density | concentration and immersion time so that a polarizing plate might become predetermined | prescribed transmittance | permeability. In this Example, 0.2 weight part of iodine was mix | blended with respect to 100 weight part of water, and it was immersed for 60 second in the aqueous solution of iodine obtained by mix | blending 1.0 weight part of potassium iodide (dyeing process).

Subsequently, it was immersed for 30 second in the crosslinking bath (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, the laminate is immersed in a boric acid aqueous solution (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) at a liquid temperature of 70 ° C, between rolls having different circumferential speeds. Uniaxial stretching was performed so that a total draw ratio might be 5.5 times in the longitudinal direction (length direction) (underwater stretching treatment).

Then, the laminated body was immersed in the washing bath (water solution obtained by mix | blending 4 weight part of potassium iodide with respect to 100 weight part of water) of liquid temperature of 30 degreeC (washing process).

By the above, the optical film laminated body containing the polarizer of thickness 5micrometer and boric acid content 16% was obtained. Boric acid content in a polarizer was measured by the following method.

About the obtained polarizer, boric acid peak (665cm <^-1> ) by a total reflection attenuation spectroscopy (ATR) measurement which makes polarization a measurement light using a Fourier transform infrared spectrophotometer (FTIR) (made by Perkin Elmer, brand name "SPECTRUM2000") The intensity of and the intensity of the reference peak (2941cm ^-1 ) were measured. From the obtained boric acid peak intensity and reference peak intensity, the amount of boric acid index was computed by the following formula, and boric acid content (weight%) was determined by the following formula from the calculated boric acid quantity index.

(Boric acid index) = (strength of boric acid peak 665 cm ^-1 ) / (intensity of reference peak 2941 cm ^-1 )

(Boric acid content (% by weight)) = (boric acid amount index) x 5.54 + 4.1

(Production of the transparent protective film)

Transparent protective film: It corona-treated and used for the easily-treated process surface of the (meth) acrylic resin film which has a thickness (40 micrometers lactone ring structure).

(Production of adhesive applied to transparent protective film)

40 weight part of N-hydroxyethyl acrylamide (HEAA), 60 weight part of acryloyl morpholine (ACMO), and 3 weight part of photoinitiator "IRGACURE 819" (made by BASF) were mixed, and the ultraviolet curable adhesive agent was prepared.

(Production of single protection polarizing film)

After bonding the said transparent protective film to the surface of the polarizer of the said optical film laminated body so that the thickness of the adhesive bond layer after hardening may be set to 0.5 micrometer, ultraviolet-ray is irradiated as an active energy ray, and an adhesive agent Was cured. Ultraviolet irradiation is a gallium-enclosed metal halide lamp, irradiation apparatus: Light HAMMER10 manufactured by Fusion UV Systems, Inc., bulb: V bulb, peak illuminance: 1600 mW / cm 2, accumulated dose 1000 / mJ / cm 2 (wavelength 380 to 440 nm) , And the illuminance of the ultraviolet ray was measured using a Sola-Check system manufactured by Solatell. Subsequently, the amorphous PET base material was peeled off and the single protection polarizing film using the thin polarizer was produced. When the single transmittance polarizing film of polarizer was measured using the obtained single protection polarizing film by the following method, the single transmittance T of the polarizer was 42.8%, and the polarization degree P of the polarizer was 99.99%.

The single transmittance T and polarization degree P of the polarizer of the obtained piece protection polarizing film were measured using the spectral transmittance measuring instrument (Dot-3c of Murakami Shikisai Genjugen Genjojo) provided with an integrating sphere.

In addition, the polarization degree P is the transmittance | permeability (parallel transmittance | permeability: Tp) when two identical single protection polarizing films overlap so that both transmission axes may become parallel, and the transmittance | permeability when the transmission axes of both overlap so that they may cross (orthogonal transmittance | permeability). : It is calculated | required by applying Tc) to the following formula.

Polarization degree P (%) = {(Tp-Tc) / (Tp + Tc)} ^1/2 × 100

Each transmittance | permeability is represented by the Y value which corrected the visibility by the 2-degree field of view (C light source) of JIS Z8701 as 100% of the fully polarized light obtained through the gran taylor prism polarizer.

<Formation of Adhesive Layer>

(Preparation of acrylic pressure-sensitive adhesive A)

In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler, 93.82 parts of n-butyl acrylate, 4 parts of methyl methacrylate, 1.5 parts of N-vinylpyrrolidone, 0.2 parts of acrylic acid, and 4- A monomer mixture containing 0.48 parts of hydroxybutyl acrylate was added. To 100 parts of the monomer mixture (solid content), 0.15 part of 2,2'-azobisisobutyronitrile was added together with ethyl acetate as a polymerization initiator, and nitrogen-substituted by introducing nitrogen gas with gentle stirring, The liquid temperature in the flask was maintained at around 60 ° C to carry out the polymerization reaction for 7 hours. Thereafter, ethyl acetate was added to the obtained reaction solution to prepare a solution of an acrylic polymer having a weight average molecular weight of 1.3 million adjusted to a solid content concentration of 20%.

The weight average molecular weight (Mw) of the said acrylic polymer was measured using the Tosoh Corporation GPC apparatus (HLC-8220GPC). Measurement conditions are as follows.

Sample concentration: 0.2 mass% (THF solution)

Sample injection volume: 10 μl

Eluent: THF

Flow rate: 0.6ml / min

Measuring temperature: 40 ℃

Column: sample column; TSK guard column Super HZ-H (one) + TSK gel Super HZM-H (two)

Reference column; TSK gel Super H-RC (1)

Detector: Differential Refractometer (RI)

The weight average molecular weight was calculated | required in polystyrene conversion value.

To 100 parts of solid content of the prepared acrylic polymer solution, 1.5 parts of lithium bis (trifluoromethanesulfonyl) imide (made by Mitsubishi Material Denshi Kasei Co., Ltd.), and ethyl methyl pyrrolidinium bis (trifluoromethanesulfonyl) imide 1 part of de (Tokyo Kasei Kogyo Co., Ltd.), 0.17 part of isocyanate type crosslinking agent (Mitsui Chemical Co., Ltd. make, brand name "Takenate D160N"), 0.25 parts of peroxide type crosslinking agent (made by Nippon Yushi Corporation, brand name "niper BMT"), and rework 0.1 part of improvers (Kaneka Corporation make, brand name "SAT10") were mix | blended, and acrylic adhesive A was prepared.

(Preparation of acrylic adhesives B-I)

In preparation of the said acrylic adhesive A, the composition of the monomer was changed as shown in Table 1, the solution of the acrylic polymer was prepared by the same method except having adjusted the polymerization conditions, and acrylic adhesives B-I were prepared.

(Formation of Adhesive Layer)

Subsequently, the prepared acrylic adhesives A to I were uniformly coated on a surface of a polyethylene terephthalate film (separator film) treated with a silicone release agent with a fountain coater, respectively, and dried for 1 minute in an air circulation type constant temperature oven at 155 ° C. An adhesive layer was formed on the surface of each separator film, respectively.

The compound of Table 1 is as follows.

BA: n-butylacrylate

MMA: Methyl methacrylate

NVP: N-vinylpyrrolidone

AA: acrylic acid

4HBA: 4-hydroxybutyl acrylate

LiTFSi: lithium bis (trifluoromethanesulfonyl) imide (manufactured by Mitsubishi Material Denshi Kasei Co., Ltd.)

EMPTFSi: ethylmethylpyrrolidinium-bis (trifluoromethanesulfonyl) imide (manufactured by Tokyo Kasei Kogyo Co., Ltd.)

SAT10: rework enhancer (manufactured by Kaneka Corporation)

Examples 1-11, Comparative Examples 1 and 2

<Production of Single Protection Polarizing Film with Adhesive Layer>

The produced adhesive layer was bonded each to the polarizer side of the produced single protection polarizing film, and the single protection polarizing film provided with the adhesive layer was produced, respectively.

The following measurement and evaluation were performed about the single protection polarizing film provided with the adhesive layer and adhesive layer obtained above. The results are shown in Table 2.

<Measurement of peak absorbance>

In the monomer component in an adhesive using the Fourier Transform Infrared Spectrophotometer (FTIR) (made by Perkin Elmer, brand name "FT-IR Spectrometer Frontier") with respect to the adhesive layer surface side of the obtained protective layer polarizing film. The absorbance was measured by total reflection measurement (ATR) with respect to the stretching vibration derived from the ester bond of. It measured on the conditions of 8 times of integration times, and the resolution of -4cm <^-1> . The absorbance peak in the range of ^-1 to a peak absorbance 1100~1130cm Abs (a) is derived from the inverse of the symmetric stretching vibration of a COC bond as methyl (meth) acrylate, and the absorbance in the range of ^-1 1150~1260cm The peak is taken as the peak absorbance Abs (b) derived from the antisymmetric stretching vibration of the COC bond of the alkyl (meth) acrylate, and the lowest absorbance (baseline) in the range of 800 to 900 cm ⁻¹ is taken as the absorbance Abs (c. ). And each absorbance obtained was substituted into the following formula, and IR parameter was computed.

Suppression of Nano Slits: Other Peak Tests

What cut | disconnected the piece protection polarizing film provided with the adhesive layer obtained by the Example and the comparative example to the size (50 mm of absorption axis direction) of 50 mm x 150 mm was made into the sample 11. The sample 11 bonded and used the surface protection film 6 produced by the following method to the side of the protective film 2.

(Surface protection film for test)

94 mass parts of 2-ethylhexyl acrylate (2EHA), 1 mass part of N, N-diethyl acrylamide (DEAA), ethoxydiethylene in the four neck flask equipped with a stirring blade, a thermometer, a nitrogen gas introduction tube, and a cooler 1 part by mass of glycol acrylate (EDE), 4 parts by mass of 4-hydroxybutyl acrylate (HBA), 0.2 part by mass of 2,2'-azobisisobutyronitrile and 150 parts by mass of ethyl acetate are added as a polymerization initiator, Nitrogen gas was introduce | transduced with gentle stirring, the liquid temperature in the flask was kept at 60 degreeC, and polymerization reaction was performed for 5 hours, and the acrylic polymer solution (40 mass%) was prepared. The weight average molecular weight of the said acrylic polymer was 570,000, and glass transition temperature (Tg) was -68 degreeC.

The acryl-based polymer solution (40% by mass) is diluted to 20% by mass with ethyl acetate, and isocyanurate of hexamethylene diisocyanate (Nippon Polyurethane Co., Ltd.) is applied to 500 parts by mass (100 parts by mass of solids) of the solution. 2 mass parts (dimass tin dilaurate) (1 mass% ethyl acetate solution) 2 mass parts (solid content 0.02 mass part) is added as manufacture, 2 mass parts (solid content 2 mass parts) of coronate HX: C / HX, and a crosslinking catalyst, and it mixes Stirring was performed, and the acrylic adhesive solution was prepared.

The acrylic pressure-sensitive adhesive solution was applied to a transparent polyethylene terephthalate (PET) film (polyester film) having a thickness of 38 μm, heated at 130 ° C. for 1 minute to form a pressure-sensitive adhesive layer having a thickness of 15 μm to prepare a surface protective film. .

Next, as shown in the conceptual diagram of FIG. 3A and the cross-sectional view of FIG. 3B, the release sheet (separator) is peeled from the sample 11 and the glass plate (through the exposed pressure-sensitive adhesive layer 4). 20). Subsequently, 200 g of loads were applied to the center part of the sample 11 (surface protective film 6 side) by the other peak (The HISTORY company make, model number "HP2H (HARD)"), and the polarizer 1 in the sample 11 50 reciprocating loads were repeated at a distance of 100 mm in the direction orthogonal to the absorption axis. The load was performed at one place. In addition, the said load was performed at high speed (5 m / min).

Subsequently, after leaving Sample 11 in an environment at 80 ° C. for 1 hour, the presence or absence of cracks in light leakage of Sample 11 was confirmed by the following criteria.

◎: 0 to 10

○: 11-30

×: 31 or more

FIG. 4 becomes an following index of confirmation of the crack (nano slit a) of light leakage in the other peak test of the single protection polarizing film 11 provided with the adhesive layer, and is an example of the photograph of the microscope of the surface of a polarizing film. to be. In FIG. 4A, the crack of light leakage by the nano slit a was not confirmed. On the other hand, FIG. 4B is a case where three cracks of light leakage by the nano slit a are generated in the absorption axis direction of the polarizer by heating. 4, the sample which the nano slit generate | occur | produced was observed with the differential interference microscope. When the sample was imaged, a sample in which no nano slits were generated was set to cross nicol on the lower side (transmission light source side) of the sample in which the nano slits were generated, and observed with transmitted light.

<Evaluation of reworkability>

The piece cut | disconnected by 32 inch was used as the sample for the single protection polarizing film provided with the produced adhesive layer. This sample was affixed on the alkali free glass plate using a laminator, and then autoclaved at 50 degreeC and 5 atm for 15 minutes, and it fully adhered. Then, the adhesive force (N / 25mm) at the time of reworking on the conditions of peeling angle 90 degrees and peeling speed 300mm / min was measured using the rework apparatus. And it evaluated on the following criteria.

◎: 3 (N / 25mm) or less

○: 3 (N / 25mm) over 6 (N / 25mm) or less

×: more than 6 (N / 25mm)

<Evaluation of antistatic property>

After peeling the separator film of the single protection polarizing film provided with the produced adhesive layer, the surface resistance value ((ohm / square)) of the adhesive surface was measured using MCP-HT450 by Mitsubishi Chemical Corporation. Moreover, the single protection polarizing film provided with the produced adhesive layer was cut into the magnitude | size of 100 mm x 100 mm, and was affixed on the liquid crystal panel. The panel was placed on a backlight having a luminance of 10,000 cd and an electrostatic discharge of 15 kV was generated using ESD (ESD-8012A, SANKI Co., Ltd.), an electrostatic generating device, to cause orientation disturbance of the liquid crystal. The recovery time (seconds) of the display defect due to the orientation defect was measured using an instantaneous multi-photometric detector (MCPD-3000, manufactured by Otsuka Denshi Co., Ltd.). And it evaluated on the following criteria.

◎: within 5 seconds

○: 5 seconds or more and 7 seconds or less

△: more than 7 seconds and 10 seconds or less

×: more than 10 seconds

From Table 2, it turns out that the single protection polarizing film provided with the adhesive layers of Examples 1-11 is hard to produce a crack, and is excellent in rework property and an antistatic function. On the other hand, it turns out that the single protection polarizing film provided with the adhesive layers of Comparative Examples 1 and 2 is inferior in any of the function of suppressing cracks, reworking properties, or antistatic function.

The single protection polarizing film provided with the adhesive layer of this invention is used for image display apparatuses, such as a liquid crystal display device (LCD) and an organic electroluminescence display, alone or as an optical film which laminated | stacked this.

1: polarizer
2: protective film
3: adhesive layer, etc.
4: adhesive layer
5, 5a, 5b: separator
6, 6a, 6b: surface protective film
10: single protection polarizing film
11: single protection polarizing film provided with adhesive layer
20a, 20b: winding object (roll) of single protection polarizing film provided with an adhesive layer
21a, 21b: single protection polarizing film provided with an adhesive layer (with surface protection film)
100: continuous manufacturing system of the image display device
101a, 101b: polarizing film supply unit
151a, 151b: dispenser
152a, 152b: cutting part
153a, 153b: peeling part
154a, 154b: winding part
201a, 201b: junction
300: batch switching unit
P: Image display panel
X: conveyance part of an image display panel

Claims (12)

It is an adhesive layer containing a (meth) acrylic-type polymer as a base polymer,
The (meth) acrylic polymer contains, as monomer units, an alkyl (meth) acrylate having 2 to 12 carbon atoms of an alkyl group, and methyl (meth) acrylate,
The said adhesive layer satisfy | fills following formula (1), The adhesive layer characterized by the above-mentioned.

Abs (a): Peak absorbance derived from antisymmetric stretching vibration of COC bond of methyl (meth) acrylate in IR measurement by total reflection measurement method of the pressure-sensitive adhesive layer
Abs (b): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the peak absorbance derived from the antisymmetric stretching vibration of the COC bond of the alkyl (meth) acrylate
Abs (c): In the IR measurement by the total reflection measurement method of the pressure-sensitive adhesive layer, the lowest absorbance in the range of 800 ~ 900cm ^-1 The method of claim 1,
The pressure-sensitive adhesive layer contains the alkali metal salt. The method according to claim 1 or 2,
The said adhesive layer is an adhesive layer containing a rework improvement agent. The method according to any one of claims 1 to 3,
The said adhesive layer is an adhesive layer whose thickness is 25 micrometers or less. A pressure-sensitive adhesive layer having a pressure-sensitive adhesive layer according to any one of claims 1 to 4, which has a protective film on only one side of the polarizer and a polarizer side of the single protective polarizing film, directly or through a coating layer. Single protective polarizing film. The method of claim 5,
The said polarizer is a single protection polarizing film provided with the adhesive layer whose thickness is 12 micrometers or less. The method according to claim 5 or 6,
The said polarizer contains polyvinyl alcohol-type resin, and the optical characteristic represented by the single transmittance T and the polarization degree P is a following formula.
P>-(10 ^{0.929T-42.4-1} ) × 100 (where T <42.3) or
The single protection polarizing film provided with the adhesive layer which is comprised so that the condition of P≥99.9 (however, T≥42.3) may be satisfied. The method according to any one of claims 5 to 7,
The said polarizer is a single protection polarizing film provided with the adhesive layer which contains boric acid in 25 weight% or less with respect to polarizer whole quantity. The method according to any one of claims 5 to 8,
The single protective polarizing film provided with the adhesive layer in which the separator is provided in the said adhesive layer. The method of claim 9,
The single protection polarizing film provided with the adhesive layer which is a winding body. The image display apparatus which has a single protection polarizing film provided with the adhesive layer in any one of Claims 5-8. The surface of an image display panel was passed through the pressure-sensitive adhesive layer from the winding body of the single-protective polarizing film provided with the pressure-sensitive adhesive layer according to claim 10 and provided with the pressure-sensitive adhesive layer conveyed by the separator. The continuous manufacturing method of an image display apparatus including the process of bonding continuously to the.

Images