JP2008003556A - Set of polarizing film with adhesive, optical laminate and polarizing film - Google Patents

Abstract

Provided is a polarizing film with an adhesive that is less likely to cause white spots when applied to a liquid crystal display device, has no change in appearance, has excellent durability, and can suppress white spots even when enlarged.
A polarizing film 15 having a configuration of an amorphous cyclic polyolefin resin film 12 / a polarizer 13 / a protective film 14, and an adhesive layer 11 provided outside the amorphous cyclic polyolefin resin film 14. The pressure-sensitive adhesive layer 11 is provided with the pressure-sensitive adhesive layer 10 having a gel fraction of 75 to 95% by weight. This polarizing film 10 with an adhesive is stuck on one side of a glass cell 35 for liquid crystal display to form an optical laminate. On the other surface of the glass cell 35, a second polarizing film 25 having a configuration of the protective film 22 / polarizer 23 / protective film 24 is attached via the second adhesive layer 21. When the protective film 22 is acetylcellulose-based, the second adhesive layer 21 is composed of a material having a low gel fraction.
[Selection] Figure 3

Description

  The present invention is for bonding a polarizing film with a pressure-sensitive adhesive film used by bonding to a glass cell for liquid crystal display, an optical layered body in which the polarizing film is bonded to a glass cell for liquid crystal display, and both surfaces of a glass cell for liquid crystal display. It relates to a set of polarizing films. The present invention also relates to a method for producing a polarizing film with an adhesive.

  A glass cell for liquid crystal display generally used in liquid crystal display devices such as TN (Twisted Nematic) and STN (Super Twisted Nematic) has a structure in which a liquid crystal component is sandwiched between two glass substrates. And on the surface of each glass substrate, optical films, such as a polarizing film, a phase difference film, and an antireflection film, are laminated | stacked through the adhesive which has an acrylic resin as a main component. In many cases, a surface treatment layer such as an antireflection layer is provided on the display surface side surface of the polarizing film. Therefore, an optical laminate that is laminated in the order of surface treatment layer / polarizing film / adhesive layer / glass cell for liquid crystal display / adhesive layer / polarizing film is generally used.

  The pressure-sensitive adhesive layer in such an optical laminate has a large dimensional change due to expansion and contraction under heat or wet heat conditions, and therefore foams in the pressure-sensitive adhesive layer of the obtained optical laminate or floats between the pressure-sensitive adhesive layer and the glass substrate. There was a problem that peeling occurred. Furthermore, the distribution of residual stress acting on the surface treatment layer and the optical film such as the polarizing film becomes non-uniform under heat or wet heat conditions, resulting in stress concentration at the outer periphery of the optical laminate. There is a problem that the outer peripheral portion sometimes becomes whitish, and the STN liquid crystal cell has a problem of uneven color in the outer peripheral portion.

  Liquid crystal display devices are also used for in-vehicle applications such as car navigation systems. However, in such in-vehicle applications, durability such as foaming, floating, peeling, and clouding does not occur even under high temperature and high humidity conditions. Sex is also needed.

  In order to solve such a problem, for example, in Japanese Patent Application Laid-Open No. 2006-77224 (Patent Document 1), a crosslinking agent is blended with two kinds of acrylic resins having different weight average molecular weights so that the gel fraction is 10 to 50% by weight. An optical laminate having a polarizing film pasted on both surfaces of a liquid crystal display glass cell via this adhesive is white even when exposed to high temperature drying conditions and high temperature and high humidity conditions. It is described that generation | occurrence | production of is suppressed.

  Furthermore, when there is a defect when the polarizing film with the adhesive layer is bonded to the glass cell for liquid crystal display, the polarizing film is peeled off and then reattached. The film is peeled off along with the polarizing film, so that an adhesive layer does not remain on the glass substrate, and so-called reworkability that does not cause fogging is also required. Patent Document 1 describes that the optical film provided with the pressure-sensitive adhesive disclosed therein is excellent in such reworkability.

  On the other hand, many polarizing films have a structure in which a polarizer made of a polyvinyl alcohol-based resin is sandwiched from both sides by a protective film made of an acetylcellulose-based resin typified by triacetylcellulose, but at least one of the protective films is There is an attempt to change to an amorphous cyclic polyolefin resin film using norbornene or the like as a monomer. For example, in Japanese Patent Laid-Open No. 8-43812 (Patent Document 2), in a polarizing film in which protective films are laminated on both sides of a polarizer, at least one of the protective films is a retardation function made of a thermoplastic norbornene resin. It describes that it is set as the film which has this. JP-A-2005-208456 (Patent Document 3) discloses a structure in which a cyclic polyolefin resin film is laminated on one surface of a polarizer made of polyvinyl alcohol resin, and an acetyl cellulose film is laminated on the other surface. Is disclosed.

Japanese Patent Laying-Open No. 2006-77224 (Claim 1, Example) JP-A-8-43812 JP-A-2005-208456

  A first polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is placed on one surface of a glass cell for liquid crystal display via an adhesive layer on the amorphous cyclic polyolefin resin film side. In the other surface, a second polarizing film in which an acetylcellulose-based protective film is bonded to both surfaces of a polarizer is stacked via an adhesive layer, as disclosed in Patent Document 1. When a pressure sensitive adhesive having a low gel fraction and high flexibility is applied to both surfaces of a glass substrate, the adhesive aggregates when left at a high temperature (for example, 80 ° C. drying condition) for a long time (for example, 100 hours). It has become clear that due to the lack of force, there is a possibility that the durability and durability may be insufficient due to floating, peeling, bubbles, etc. between the adhesive layer and the amorphous cyclic polyolefin-based resin film. In addition, a polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is laminated on both surfaces of a glass cell for liquid crystal display on the amorphous cyclic polyolefin resin film side through an adhesive layer. At that time, it has been clarified that the same problem occurs even when an adhesive having a low gel fraction and high flexibility is applied.

  Therefore, when the present invention is applied to a liquid crystal display device, it is difficult to cause white spots even when exposed to high-temperature conditions, high-temperature and high-humidity conditions, or repeated heating and cooling. Another object of the present invention is to provide a polarizing film with a pressure-sensitive adhesive that does not cause changes in appearance such as foaming and cloudiness, has excellent durability, and can suppress white spots even when the size is increased. Another object of the present invention is to provide an optical laminate in which such a polarizing film with an adhesive is applied to a glass cell for liquid crystal display, and the polarizing film with an adhesive is bonded to a glass cell for liquid crystal display. It is providing the set of the polarizing film used as one polarizing film.

  As a result of intensive studies to solve such problems, the present inventors have found that a polarizing film having an amorphous cyclic polyolefin resin film bonded to one side of a polarizer has a high gel fraction. It has been found effective to apply the agent. And the 1st polarizing film which consists of a structure of an amorphous cyclic polyolefin resin film / polarizer / protective film is put on the one side of the glass cell for liquid crystal displays via the 1st adhesion layer. When the second polarizing film in which an acetylcellulose-based protective film is bonded to both sides of the polarizer is laminated on the other side of the glass cell, the glass cell for liquid crystal display It has been found that it is more effective to use different pressure-sensitive adhesives as pressure-sensitive adhesives to be bonded on both sides. In addition, a polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is provided on both sides of the glass cell for liquid crystal display on the amorphous cyclic polyolefin resin film side through an adhesive layer. In the case of laminating, it has also been found that it is advantageous to configure each adhesive layer with an adhesive having a high gel fraction. The present invention has been completed based on such findings and further various studies.

  That is, according to the present invention, from the first standpoint, the polarizing film having the structure of amorphous cyclic polyolefin resin film / polarizer / protective film and the outside of the amorphous cyclic polyolefin resin film were provided. The pressure-sensitive adhesive layer is provided with a pressure-sensitive adhesive layer having a gel fraction of 75 to 95% by weight. Here, the pressure-sensitive adhesive layer is preferably formed of a pressure-sensitive adhesive in which a crosslinking agent is blended with an acrylic resin. A brightness enhancement film can be laminated on the outside of the protective film.

  According to the invention, from the second standpoint, an optical laminated body in which the polarizing film with the adhesive specified from the first standpoint is attached to one side of the glass cell for liquid crystal display on the sticking layer side. Is also provided. A preferred form of this optical laminate is a first polarizing film comprising an amorphous cyclic polyolefin resin film / polarizer / protective film on one side of a glass cell for liquid crystal display with a first adhesive layer interposed therebetween. Is attached on the amorphous cyclic polyolefin resin film side, and on the other surface of the glass cell is a second polarizing film in which an acetylcellulose-based protective film is bonded to both surfaces of the polarizer. The first adhesive layer has a gel fraction of 75 to 95% by weight, and the second adhesive layer has a gel fraction of 30 to 70% by weight. It is. The second polarizing film can have a surface treatment layer on the surface opposite to the second adhesive layer.

  Another preferred form of the optical laminate is a first polarized light composed of an amorphous cyclic polyolefin resin film / polarizer / protective film on one side of a glass cell for liquid crystal display via a first adhesive layer. A film is attached on the amorphous cyclic polyolefin resin film side, and on the other surface of the glass cell, there is a second polarizing film having a structure of amorphous cyclic polyolefin resin film / polarizer / protective film. It is affixed on the amorphous cyclic polyolefin-based resin film side, and both the first adhesive layer and the second adhesive layer have a gel fraction of 75 to 95% by weight. Also in this case, the second polarizing film can have a surface treatment layer on the surface opposite to the second adhesive layer.

  Furthermore, according to this invention, the set of the polarizing film bonded together on both surfaces of the glass cell for liquid crystal display devices from the 3rd viewpoint is also provided. This set of polarizing films is a combination of a polarizing film with a first pressure-sensitive adhesive and a polarizing film with a second pressure-sensitive adhesive, and the first polarizing film with a pressure-sensitive adhesive is an amorphous cyclic polyolefin-based resin film / polarized light. A first polarizing film having a structure of a child / protective film and a first adhesive layer provided on the outer side of the amorphous cyclic polyolefin-based resin film. The second polarizing film with an adhesive is The second polarizing film having an acetylcellulose-based protective film bonded on both sides of the polarizer, and the second adhesive layer provided on one side thereof, and the first adhesive layer is The gel fraction is 75 to 95% by weight, and the second adhesive layer has a gel fraction of 30 to 70% by weight.

  Furthermore, according to the present invention, from the fourth viewpoint, an adhesive layer is provided on the amorphous cyclic polyolefin resin film side of the polarizing film having the structure of amorphous cyclic polyolefin resin film / polarizer / protective film. In this case, the pressure-sensitive adhesive layer is prepared such that the gel fraction is 75 to 95% by weight and provided on the surface of the amorphous cyclic polyolefin-based resin film of the polarizing film, thereby producing a polarizing film with a pressure-sensitive adhesive. Is also provided.

  A polarizing film having a structure of an amorphous cyclic polyolefin resin film / polarizer / protective film has a small photoelastic coefficient of the amorphous cyclic polyolefin resin film and hardly causes a change in phase difference. Although white spots are unlikely to occur, the adhesive strength of the amorphous cyclic polyolefin-based resin film is weak, and foaming, floating, and peeling are likely to occur. Therefore, in the polarizing film with an adhesive of the present invention, an adhesive having a high gel fraction and a high cohesive force is used as an adhesive layer for adhering to the glass cell for liquid crystal display on the amorphous cyclic polyolefin resin film side. By using it, generation | occurrence | production of foaming, a float, peeling, etc. can be suppressed. Moreover, this polarizing film with an adhesive is excellent also in the rework property when bonding to the glass cell for liquid crystal displays.

  The optical layered body of the present invention is obtained by sticking the above polarizing film with an adhesive to one side of a glass cell for liquid crystal display, and can suppress the occurrence of foaming, floating, peeling, etc. accompanying a temperature change or the like. . In a preferred form of this optical laminate, an amorphous cyclic polyolefin resin film is used as a constituent element on one side of a glass cell for liquid crystal display via a first adhesive layer having a high gel fraction and a high cohesive force. A second polarizing film in which an acetylcellulose-based protective film is bonded to both sides of a polarizer on the other surface of the glass cell, the gel fraction is low, and the cohesive force Are laminated via a small second adhesive layer. In this embodiment, the stress caused by the dimensional change of the second polarizing film and the dimensional change of the glass substrate is absorbed and relaxed by the second adhesive layer between the second polarizing film and the glass cell under heat resistant conditions. As a result, local stress concentration is reduced, and the floating and peeling of the adhesive layer with respect to the glass substrate are suppressed, and optical defects such as white spots due to uneven stress distribution are prevented.

  In another preferred form of the optical laminate, an amorphous cyclic polyolefin resin film is formed on one side of a glass cell for liquid crystal display via a first adhesive layer having a high gel fraction and a high cohesive force. The first polarizing film is laminated, and the amorphous cyclic polyolefin resin film is formed on the other surface of the glass cell via the first adhesive layer having a high gel fraction and a high cohesive force. The first polarizing film is laminated. In this form, even when placed under heat-resistant conditions, the amorphous cyclic polyolefin resin film exhibits a low photoelastic coefficient, so that optical defects such as white spots due to uneven stress distribution are prevented. . Further, by using an adhesive having a high gel fraction and a large cohesive force as the adhesive layer, the adhesion layer can be prevented from floating or peeling off from the glass substrate.

  From these facts, when the glass substrate constituting the optical laminate is a TN liquid crystal cell, white spots are suppressed, and when the glass substrate is an STN liquid crystal cell, color unevenness is suppressed. These optical laminates are less likely to have white spots even after repeated heating, do not change appearance such as floating, peeling, foaming, and fogging, have excellent durability, and have a large size of 15 or more. However, optical defects such as white spots and color unevenness are suppressed.

  Further, even if the first polarizing film together with the first adhesive layer or the second polarizing film together with the second adhesive layer is peeled off from the glass substrate of the glass cell for liquid crystal display, respectively, Since no adhesive residue and cloudiness are likely to occur, another polarizing film can be bonded to the glass cell again, and the reworkability is excellent.

  The set of polarizing films according to the present invention has a high gel fraction on the amorphous cyclic polyolefin resin film side of the first polarizing film having the structure of amorphous cyclic polyolefin resin film / polarizer / protective film. The first adhesive layer having a large cohesive force is disposed to form a first polarizing film with an adhesive, and on one side of the second polarizing film in which an acetylcellulose-based protective film is bonded to both sides of the polarizer, Since the second adhesive layer having a low gel fraction and a low cohesive force is arranged to form a second polarizing film with a pressure-sensitive adhesive, the first polarized light is bonded to each glass cell for liquid crystal display. Even if stress is generated due to dimensional change accompanying temperature change etc. on the second polarizing film side, the adhesive strength on the film side can be absorbed and relaxed by the second adhesive layer. Can . For this reason, local stress concentration is reduced, and the floating or peeling of the adhesive layer with respect to the glass substrate is suppressed, and optical defects such as white spots due to uneven stress distribution are prevented.

  Further, according to the method for producing a polarizing film with an adhesive of the present invention, an polarizing film with an adhesive having an amorphous cyclic polyolefin resin film as one protective film of a polarizer and having an adhesive layer on the surface is advantageous. Can be manufactured.

  In FIG. 1, the example of a layer structure of the polarizing film with an adhesive which concerns on this invention is shown with a cross-sectional schematic diagram, and FIG. 2 is a cross-sectional schematic example in which the brightness enhancement film was laminated | stacked on the polarizing film with an adhesive of FIG. Shown in the figure. FIG. 3 is a schematic cross-sectional view showing a preferred layer configuration of the optical laminate according to the present invention. FIG. 4 shows the outer side of the protective film of the first polarizing film in the optical laminate of FIG. An example in which the brightness enhancement film is laminated and the second polarizing film has a surface treatment layer on the side opposite to the adhesive layer is shown in a schematic cross-sectional view. The embodiment of the present invention will be described in detail with reference to these drawings.

[Polarized film with adhesive]
First, referring to FIG. 1 and referring to FIG. 2 as necessary, the polarizing film with an adhesive will be described. As shown in FIG. 1, a polarizing film 10 with an adhesive of the present invention includes a first polarizing film 15 having a configuration of an amorphous cyclic polyolefin resin film 12 / a polarizer 13 / a protective film 14, and an amorphous film. It has the adhesion layer 11 provided in the outer side of the property cyclic polyolefin-type resin film 12. FIG.

  The polarizer 13 constituting the polarizing film 15 has a function of emitting polarized light with respect to incident light such as natural light. Usually, such a polarized light emission function is manifested by a function of absorbing linearly polarized light having a vibration surface in a certain direction and transmitting linearly polarized light having a vibration surface orthogonal thereto. The polarizer 13 can be composed of a uniaxially stretched polyvinyl alcohol resin film in which a dichroic dye such as iodine or a dichroic dye is adsorbed and oriented. Such a polarizer is generally produced by subjecting a polyvinyl alcohol resin film to uniaxial stretching, dyeing with a dichroic dye, and boric acid treatment.

  A protective film made of the amorphous cyclic polyolefin resin film 12 is disposed on one side of the polarizer 13. Here, the amorphous cyclic polyolefin-based resin is a resin having a cyclic olefin such as norbornene or polycyclic norbornene as a monomer, and the degree of hydrogenation is saturated by hydrogenation of the ring-opened polymer of these cyclic olefins. Or a copolymer of a cyclic olefin and a chain olefin. Of these, a thermoplastic saturated norbornene resin is advantageously used. Those having a polar group introduced are also effective. Commercially available amorphous cyclic polyolefin-based resins include “Arton” sold by JSR, “ZEONEX” and “ZEONOR” sold by Optes, and Mitsui Chemicals. “APO” and “Apel” (both are trade names). As described above, the amorphous cyclic polyolefin resin has a small photoelastic coefficient and is unlikely to cause a phase change due to a temperature change. It is valid.

  The thickness of the amorphous cyclic polyolefin-based resin film 12 is usually about 10 to 120 μm, and preferably about 20 to 80 μm.

  The amorphous cyclic polyolefin resin film 12 may be stretched uniaxially or biaxially to exhibit a predetermined birefringence. In this case, the draw ratio is usually about 1.1 to 5 times, preferably 1.1 to 3 times, and the in-plane retardation value is usually about 20 to 200 nm. When using such a film exhibiting birefringence, the film 12 is arranged so that the slow axis of the film 12 is parallel or orthogonal to the transmission axis of the polarizer 13, so that the front surface perpendicular to the polarizing film surface is obtained. In the direction, it is possible to prevent the decrease in brightness and contrast without being affected by the phase difference due to the transparent protective layer. Therefore, a highly visible region having excellent contrast and brightness can be enlarged, and a liquid crystal display device with a wide viewing angle can be obtained.

  A protective film 14 is disposed on the other surface of the polarizer 13. For the protective film 14, a transparent resin film is used. Examples of the transparent resin include acetyl cellulose resins such as triacetyl cellulose and diacetyl cellulose, methacryl resins such as polymethyl methacrylate, polyester resins, polyolefin resins, and polycarbonates. Resins, polyether ether ketone resins, polysulfone resins and the like can be mentioned. The resin constituting the protective film may contain an ultraviolet absorber such as a salicylic acid ester compound, a benzophenone compound, a benzotriazole compound, a triazine compound, a cyanoacrylate compound, or a nickel complex compound. The protective film 14 is preferably composed of an acetylcellulose-based resin, and a triacetylcellulose film is particularly preferably used. The thickness of the protective film 14 is usually about 30 to 120 μm.

  A transparent adhesive is usually used for bonding the polarizer 13 and the amorphous cyclic polyolefin-based resin film 12 and the polarizer 13 and the protective film 14. For example, an aqueous adhesive such as an aqueous solution of a polyvinyl alcohol resin is preferably used.

[Adhesive layer of polarizing film with adhesive]
An adhesive layer 11 is provided on the outer side (the side not facing the polarizer 13) of the amorphous cyclic polyolefin-based resin film 12 constituting the polarizing film 15. In the present invention, the pressure-sensitive adhesive layer 11 has a gel fraction of 75 to 95% by weight. Hereinafter, the adhesive layer 11 will be described in detail.

  The pressure-sensitive adhesive layer 11 is generally formed from a pressure-sensitive adhesive obtained by blending a crosslinking agent with an acrylic resin. Usually, it is cured to form an adhesive layer. Specifically, the acrylic resin used in the adhesive layer is mainly composed of structural units derived from (meth) acrylic acid alkyl esters, such as free carboxyl groups, hydroxyl groups, amino groups, and heterocyclic groups including epoxy rings. It can include a structural unit derived from a monomer having a polar functional group, preferably a (meth) acrylic acid compound having a polar functional group. Here, (meth) acrylic acid means that either acrylic acid or methacrylic acid may be used, and “(meth)” in the case of (meth) acrylate or the like has the same meaning.

  (Meth) acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, isooctyl acrylate, lauryl acrylate, stearyl acrylate Alkyl acrylates such as benzyl acrylate, methoxyethyl acrylate, ethoxymethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid Octyl acid, isooctyl methacrylate, lauryl methacrylate, stearyl methacrylate, benzyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate Can, methacrylic acid alkyl esters. These (meth) acrylic acid alkyl esters can be used alone or in combination with a plurality of different ones.

  Examples of the monomer having a polar functional group include monomers having a free carboxyl group such as acrylic acid, methacrylic acid, and β-carboxyethyl acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxy (meth) acrylate Monomers having a hydroxyl group such as propyl, 2- or 3-chloro-2-hydroxypropyl (meth) acrylate, diethylene glycol mono (meth) acrylate; acryloylmorpholine, vinylcaprolactam, N-vinyl-2-pyrrolidone, tetrahydrofurfuryl Has a heterocyclic group such as (meth) acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, glycidyl (meth) acrylate, 2,5-dihydrofuran That monomers; N, such as N- dimethylaminoethyl (meth) acrylate, and the like monomers having different amino group and heterocyclic. These monomers having polar functional groups can be used alone or in combination with a plurality of different monomers.

  The acrylic resin used for the adhesive layer has a structural unit derived from (meth) acrylic acid alkyl ester, usually 60 to 99.9 parts by weight, preferably 80 to 99.6 parts by weight, based on 100 parts by weight of the nonvolatile content. The structural unit derived from the monomer having a polar functional group is usually contained in an amount of 0.1 to 20 parts by weight, preferably 0.4 to 10 parts by weight.

  The acrylic resin used in the present invention may contain a structural unit derived from a monomer other than the (meth) acrylic acid alkyl ester and the monomer having a polar functional group described above. Examples of these include (meth) acrylic acid ester having an alicyclic structure in the molecule, a structural unit derived from a styrene monomer, a structural unit derived from a vinyl monomer, and a plurality of (meth) acryloyl groups in the molecule. Examples include structural units derived from monomers having a

  The alicyclic structure is a cycloparaffin structure having usually 5 or more carbon atoms, preferably about 5 to 7 carbon atoms. Specific examples of the acrylate ester having an alicyclic structure include isobornyl acrylate, cyclohexyl acrylate, dicyclopentanyl acrylate, cyclododecyl acrylate, methyl cyclohexyl acrylate, trimethyl cyclohexyl acrylate, tert-butyl acrylate Examples of methacrylic acid esters having an alicyclic structure include cyclohexyl, α-ethoxyacrylic acid cyclohexyl, cyclohexyl phenyl acrylate, etc. Specific examples of methacrylic acid esters having an alicyclic structure include isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, methacrylic acid Such as cyclododecyl, methyl cyclohexyl methacrylate, trimethyl cyclohexyl methacrylate, tert-butyl cyclohexyl methacrylate, cyclohexyl phenyl methacrylate And so on.

  Examples of styrenic monomers include styrene, alkyl styrene such as methyl styrene, dimethyl styrene, trimethyl styrene, ethyl styrene, diethyl styrene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl styrene, octyl styrene; Halogenated styrene such as styrene, chlorostyrene, bromostyrene, dibromostyrene, iodostyrene; and nitrostyrene, acetylstyrene, methoxystyrene, divinylbenzene and the like.

  Examples of vinyl-based monomers include vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate such as vinyl esters; vinyl halides such as vinyl chloride and vinyl bromide; vinylidene chloride and the like. Examples thereof include vinylidene halides; nitrogen-containing aromatic vinyls such as vinyl pyridine, vinyl pyrrolidone and vinyl carbazole; conjugated diene monomers such as butadiene, isoprene and chloroprene; and acrylonitrile and methacrylonitrile.

  Examples of monomers having a plurality of (meth) acryloyl groups in the molecule include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di ( 2 (meth) acryloyl groups in the molecule such as (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate And a monomer having three (meth) acryloyl groups in the molecule, such as trimethylolpropane tri (meth) acrylate.

  Monomers other than the (meth) acrylic acid alkyl ester and the monomer having a polar functional group can be used alone or in combination of two or more. In the acrylic resin used for the adhesive layer, the structural unit derived from a monomer other than the (meth) acrylic acid alkyl ester and the monomer having a polar functional group is usually 0 to 20 weights per 100 weight parts of the nonvolatile content of the resin. Parts, preferably 0 to 10 parts by weight.

  The active ingredient of the adhesive layer 11 contains two or more kinds of acrylic resins containing the structural unit derived from a monomer having a polar functional group, the main component of which is the structural unit derived from the (meth) acrylic acid alkyl ester. It may be a thing. Further, the acrylic resin is a mixture of an acrylic resin different from the acrylic resin, specifically, an acrylic resin having a structural unit derived from (meth) acrylic acid alkyl ester and containing no polar functional group. May be. The acrylic resin containing a structural unit derived from a monomer having a polar functional group, the main component of which is a structural unit derived from (meth) acrylic acid alkyl ester, is 60% by weight or more, and further 80% by weight of the entire acrylic resin. The above is preferable.

  An acrylic resin containing a structural unit derived from a monomer having a polar functional group, the main component of which is a structural unit derived from (meth) acrylic acid alkyl ester, is a weight in terms of standard polystyrene by gel permeation chromatography (GPC). The average molecular weight (Mw) is preferably in the range of 1,000,000 to 2,000,000. If the weight average molecular weight in terms of standard polystyrene is 1,000,000 or more, the adhesion at high temperature and high humidity will be improved, and the possibility of floating or peeling between the glass substrate and the adhesive layer tends to be reduced. Moreover, it is preferable because reworkability tends to be improved. In addition, when the weight average molecular weight is 2,000,000 or less, even if the size of the polarizing film bonded to the adhesive layer changes, the adhesive layer changes following the change in the size. This is preferable because there is no difference between the brightness of the part and the brightness of the center part, and white spots and color unevenness tend to be suppressed. The molecular weight distribution represented by the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is usually in the range of about 2 to 10.

  Acrylic resin (a mixture of both when two or more types are combined) is a solution prepared by dissolving it in ethyl acetate to a non-volatile content concentration of 20% by weight at 25 ° C., 20 Pa · s or less, and further 0.1-7 Pa. -It is preferable to show the viscosity of s. If the viscosity at this time is 20 Pa · s or less, the adhesiveness under high temperature and high humidity is improved, and the possibility of occurrence of floating or peeling between the glass substrate and the adhesive layer tends to be low. Moreover, it is preferable because reworkability tends to be improved. Viscosity can be measured with a Brookfield viscometer.

  The acrylic resin constituting the adhesive layer can be produced by various known methods such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, and a suspension polymerization method. In the production of this acrylic resin, a polymerization initiator is usually used. The polymerization initiator is used in an amount of about 0.001 to 5 parts by weight with respect to a total of 100 parts by weight of all monomers used in the production of the acrylic resin.

  As the polymerization initiator, a thermal polymerization initiator, a photopolymerization initiator, or the like is used. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone. Examples of the thermal polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl-2,2'-azobis (2-methylpropio) Azo) compounds such as 2,2'-azobis (2-hydroxymethylpropionitrile); lauryl peroxide, tert-butyl hydroperoxide, benzoyl peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide , Diisopropyl peroxydicarbonate, dipropyl peroxydicarbonate, tert-butyl peroxy Organic peroxides such as neodecanoate, tert-butyl peroxypivalate, (3,5,5-trimethylhexanoyl) peroxide; inorganic peroxides such as potassium persulfate, ammonium persulfate and hydrogen peroxide Can do. A redox initiator using a peroxide and a reducing agent in combination can also be used as the polymerization initiator.

  As a method for producing the acrylic resin, the solution polymerization method is preferable among the methods shown above. A specific example of the solution polymerization method will be described. A desired monomer and an organic solvent are mixed, and a thermal polymerization initiator is added under a nitrogen atmosphere, and is about 40 to 90 ° C, preferably about 60 to 80 ° C. And a method of stirring for about 3 to 10 hours. Moreover, in order to control reaction, you may add a monomer and a thermal-polymerization initiator continuously or intermittently during superposition | polymerization, or may be added in the state melt | dissolved in the organic solvent. Examples of the organic solvent include aromatic hydrocarbons such as toluene and xylene; esters such as ethyl acetate and butyl acetate; aliphatic alcohols such as propyl alcohol and isopropyl alcohol; acetone, methyl ethyl ketone, and methyl isobutyl ketone. Ketones such as can be used.

  Usually, a crosslinking agent is blended in the acrylic resin as described above to form an adhesive. The crosslinking agent used for this purpose is a compound having in the molecule at least two functional groups capable of crosslinking with polar functional groups. Specifically, isocyanate compounds, epoxy compounds, metal chelate compounds, aziridine compounds, etc. Can be mentioned.

  Isocyanate compounds are compounds having at least two isocyanato groups (-NCO) in the molecule, such as tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, Examples thereof include hydrogenated diphenylmethane diisocyanate, naphthalene diisocyanate, and triphenylmethane triisocyanate. In addition, adducts obtained by reacting these isocyanate compounds with polyols such as glycerol and trimethylolpropane, and those obtained by making isocyanate compounds into dimers and trimers can also be used as a crosslinking agent for the adhesive layer. Further, two or more kinds of isocyanate compounds can be mixed and used.

  The epoxy compound is a compound having at least two epoxy groups in the molecule, for example, bisphenol A type epoxy resin, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin diglycidyl ether, glycerin triglycidyl ether. 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, N, N-diglycidylaniline, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis ( N, N'-diglycidylaminomethyl) cyclohexane and the like. Two or more types of epoxy compounds may be mixed and used.

  Examples of the metal chelate compound include compounds in which acetylacetone or ethyl acetoacetate is coordinated to a polyvalent metal such as aluminum, iron, copper, zinc, tin, titanium, nickel, antimony, magnesium, vanadium, chromium, and zirconium. Can be mentioned.

  An aziridine-based compound is a compound having at least two skeletons of a three-membered ring composed of one nitrogen atom and two carbon atoms, also called ethyleneimine, for example, diphenylmethane-4,4′-bis ( 1-aziridinecarboxamide), toluene-2,4-bis (1-aziridinecarboxamide), triethylenemelamine, isophthaloylbis-1- (2-methylaziridine), tris-1-aziridinylphosphine oxide, hexamethylene -1,6-bis (1-aziridinecarboxamide), trimethylolpropane tri-β-aziridinylpropionate, tetramethylolmethane tri-β-aziridinylpropionate, and the like.

  Among these crosslinking agents, isocyanate compounds are preferably used. It is also effective to use an aziridine compound in combination with the isocyanate compound. The crosslinking agent is usually about 0.1 to 10 parts by weight, preferably 0.1 to 7 parts by weight with respect to 100 parts by weight of the nonvolatile content of the acrylic resin constituting the pressure-sensitive adhesive (the total amount when two or more types are used) About part is blended. Since the amount of the crosslinking agent is also related to the gel fraction described later, it may be appropriately selected from the above range according to the required gel fraction.

  It is preferable to mix | blend a silane type compound with an adhesive before mix | blending a crosslinking agent. Examples of the silane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-amino). Ethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl Trimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, phenyltrimethoxysilane, hexyl Silane, hexamethyl disilazane, decyl trimethoxysilane, diphenyl dimethoxysilane, 1,3,5-tris (3-trimethoxysilylpropyl) isocyanurate and the like. Two or more types of silane compounds may be used.

  As the silane compound, a polymer or oligomer type compound may be used. Examples of the polymer and oligomer type silane compounds include the following.

3-mercaptopropyltrimethoxysilane-tetramethoxysilane copolymer,
3-mercaptopropyltrimethoxysilane-tetraethoxysilane copolymer,
3-mercaptopropyltriethoxysilane-tetramethoxysilane copolymer,
A copolymer containing mercaptopropyl groups, such as a 3-mercaptopropyltriethoxysilane-tetraethoxysilane copolymer;

Mercaptomethyltrimethoxysilane-tetramethoxysilane copolymer,
Mercaptomethyltrimethoxysilane-tetraethoxysilane copolymer,
Mercaptomethyltriethoxysilane-tetramethoxysilane copolymer,
A copolymer containing a mercaptomethyl group, such as a mercaptomethyltriethoxysilane-tetraethoxysilane copolymer;

3-methacryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-methacryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-methacryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,
A methacryloyloxypropyl group-containing copolymer, such as 3-methacryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-acryloyloxypropyltrimethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropyltrimethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropyltriethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropyltriethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-acryloyloxypropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-acryloyloxypropylmethyldiethoxysilane-tetramethoxysilane copolymer,
A copolymer containing acryloyloxypropyl groups, such as 3-acryloyloxypropylmethyldiethoxysilane-tetraethoxysilane copolymer;

Vinyltrimethoxysilane-tetramethoxysilane copolymer,
Vinyltrimethoxysilane-tetraethoxysilane copolymer,
Vinyltriethoxysilane-tetramethoxysilane copolymer,
Vinyltriethoxysilane-tetraethoxysilane copolymer,
Vinylmethyldimethoxysilane-tetramethoxysilane copolymer,
Vinylmethyldimethoxysilane-tetraethoxysilane copolymer,
Vinylmethyldiethoxysilane-tetramethoxysilane copolymer,
A vinyl group-containing copolymer, such as vinylmethyldiethoxysilane-tetraethoxysilane copolymer;

3-aminopropyltrimethoxysilane-tetramethoxysilane copolymer,
3-aminopropyltrimethoxysilane-tetraethoxysilane copolymer,
3-aminopropyltriethoxysilane-tetramethoxysilane copolymer,
3-aminopropyltriethoxysilane-tetraethoxysilane copolymer,
3-aminopropylmethyldimethoxysilane-tetramethoxysilane copolymer,
3-aminopropylmethyldimethoxysilane-tetraethoxysilane copolymer,
3-aminopropylmethyldiethoxysilane-tetramethoxysilane copolymer,
Amino group-containing copolymers such as 3-aminopropylmethyldiethoxysilane-tetraethoxysilane copolymer.

  These silane-based compounds are often liquids. The compounding amount of the silane compound in the pressure-sensitive adhesive is usually about 0.0001 to 10 parts by weight, preferably 0 with respect to 100 parts by weight of the nonvolatile content of the acrylic resin (the total amount when two or more types are used). Used in a ratio of 0.01 to 5 parts by weight. It is preferable that the amount of the silane compound with respect to the nonvolatile content of 100 parts by weight of the acrylic resin is 0.0001 parts by weight or more because adhesion between the adhesive layer and the glass substrate is improved. Moreover, it is preferable for the amount to be 10 parts by weight or less because the silane compound tends to be suppressed from bleeding out from the adhesive layer.

  The pressure-sensitive adhesive described above may further contain a crosslinking catalyst, a weather stabilizer, a tackifier, a plasticizer, a softener, a dye, a pigment, an inorganic filler, and the like. In particular, when a cross-linking catalyst is blended with a cross-linking agent in the pressure-sensitive adhesive, the pressure-sensitive adhesive layer can be prepared by aging in a short time, and in the resulting optical laminate, floating or peeling occurs between the pressure-sensitive adhesive layer and the polarizing film. Or foaming in the adhesive layer can be suppressed, and reworkability can be further improved. Examples of the crosslinking catalyst include amine compounds such as hexamethylenediamine, ethylenediamine, polyethyleneimine, hexamethylenetetramine, diethylenetriamine, triethylenetetramine, isophoronediamine, trimethylenediamine, polyamino resin, and melamine resin. When an amine compound is added to the adhesive as a crosslinking catalyst, an isocyanate compound is suitable as the crosslinking agent.

  In the present invention, as described above, the pressure-sensitive adhesive layer 11 has a gel fraction of 75 to 95% by weight. Here, the gel fraction is a value measured according to the following (I) to (IV).

(I) An adhesive layer having an area of about 8 cm × about 8 cm and a metal mesh made of SUS304 (its weight is Wm) of about 10 cm × about 10 cm are bonded together.
(II) Weigh the bonded product obtained in (I) above, weigh it Ws, then fold it 4 times so as to wrap the adhesive layer, and then weigh it with a stapler (stapler). The weight is Wb.
(III) The mesh stapled in (II) above is placed in a glass container, and 60 ml of ethyl acetate is added and immersed, and then the glass container is stored at room temperature for 3 days.
(IV) The mesh is taken out from the glass container, dried at 120 ° C. for 24 hours, weighed, the weight is taken as Wa, and the gel fraction is calculated based on the following formula.

    Gel fraction (% by weight) = [{Wa− (Wb−Ws) −Wm} / (Ws−Wm)] × 100

  The gel fraction of the adhesive layer 11 is set to 75 to 95% by weight. When the gel fraction is 75% by weight or more, floating or peeling occurs between the adhesive layer 11 and the amorphous cyclic polyolefin resin film 12 constituting the polarizing film 15, or foaming occurs in the adhesive layer. It is preferable because it tends to be suppressed from occurring, and the gel fraction is preferably 95% by weight or less because it is easy to produce.

  In order to adjust the gel fraction of the pressure-sensitive adhesive layer 11 to 75 to 95% by weight, the gel fraction increases as the amount of the crosslinking agent is increased, although it varies depending on the type of acrylic resin that is an active ingredient of the pressure-sensitive adhesive layer. Therefore, what is necessary is just to adjust a gel fraction with the quantity of a crosslinking agent. Specifically, the blending amount of the crosslinking agent with respect to 100 parts by weight of the nonvolatile content of the acrylic resin constituting the adhesive layer 11 (the total amount when two or more types are used) is in the range of about 0.3 to 7 parts by weight. What is necessary is just to select suitably according to the kind of acrylic resin.

  Although the thickness of the adhesion layer 11 is not specifically limited, Usually, it is preferable that it is 30 micrometers or less, and it is preferable that it is 10 micrometers or more. If the thickness of the adhesive layer is 30 μm or less, the adhesiveness under high temperature and high humidity is improved, and there is a tendency that the possibility of floating or peeling between the glass substrate and the adhesive layer tends to be reduced. It is preferable from the tendency to improve, and if the thickness is 10 μm or more, even if the dimension of the polarizing film bonded thereto changes, the pressure-sensitive adhesive layer follows the dimensional change and fluctuates. Therefore, it is preferable because there is no difference between the brightness at the peripheral edge and the brightness at the center of the liquid crystal cell, and white spots and color unevenness tend to be suppressed.

  Conventionally, in general, the thickness of the adhesive layer for bonding to a glass cell for liquid crystal display has been about 25 μm as a standard, but in the present invention, the adhesive layer 11 provided on the amorphous cyclic polyolefin resin film 12 is used. Is preferably 20 μm or less. In general, when the pressure-sensitive adhesive layer is thickened, bubbles are easily generated, but white spots are easily suppressed. On the other hand, if the pressure-sensitive adhesive layer is thin, bubbles are less likely to be produced, but white spots are likely to occur. Since the amorphous cyclic polyolefin resin film 12 used for the polarizing film 15 in the present invention has a small photoelastic coefficient as described above, a change in retardation due to a temperature change or the like is small. For this reason, even if the pressure-sensitive adhesive layer 11 provided thereon is thinned, white spots due to that side hardly occur. Even if a dimensional change occurs in the polarizing film 15 or the amorphous cyclic polyolefin resin film 12 constituting the polarizing film 15, if the adhesive layer 11 is thin, the influence of the dimensional change on the adhesive layer is reduced. Therefore, even if the thickness of the pressure-sensitive adhesive layer 11 is reduced to 20 μm or less, white spots and the like hardly occur, and further contributes to the thinning of the entire optical laminate bonded to the glass cell for liquid crystal display. it can.

  In the polarizing film with an adhesive of the present invention, a brightness enhancement film 17 can be laminated on the outside of the protective film 14 constituting the polarizing film 15 as shown in FIG. 2 is the same as FIG. 1 except that the brightness enhancement film 17 is disposed on the outer side of the protective film 14 (on the side opposite to the adhesive layer 11), and thus the same reference numerals are given to the same portions as FIG. Detailed explanation is omitted.

  Here, the brightness enhancement film 17 is an optical film that can improve the utilization efficiency of the backlight in the liquid crystal display device. Examples of brightness enhancement films include “DBEF”, which is a reflective polarizing separation film sold by 3M Company in the US (Sumitomo 3M Co., Ltd. in Japan), and “BEF”, which is an upward prism sheet also sold by 3M Company. "Diaart" is a downward-facing prism sheet sold by Mitsubishi Rayon Co., Ltd.

[Method for producing polarizing film with adhesive]
The polarizing film with pressure-sensitive adhesive of the present invention configured as described above prepares a polarizing film 15 having a configuration of an amorphous cyclic polyolefin-based resin film 12 / a polarizer 13 / a protective film 14, and separately includes a gel fraction. A pressure-sensitive adhesive prepared to be 75 to 95% by weight is prepared, and this pressure-sensitive adhesive is applied to the surface of the amorphous cyclic polyolefin resin film 12 in the polarizing film 15 to form the pressure-sensitive adhesive layer 11. Can be manufactured. When the brightness enhancement film 17 is provided outside the protective film 14 as shown in FIG. 2, at the stage of the polarizing film 15 composed of the amorphous cyclic polyolefin resin film 12 / the polarizer 13 / the protective film 14, It is advantageous to bond the brightness enhancement film 17 to the outside of the protective film 14 via an adhesive or the like.

  In providing the pressure-sensitive adhesive layer 11 on the surface of the amorphous cyclic polyolefin-based resin film 12, a method of directly applying and drying an organic solvent solution of a pressure-sensitive adhesive prepared so that the gel fraction is 75 to 95% by weight Can be adopted. Separately, a method of forming an adhesive layer 11 having a gel fraction of 75 to 95% by weight on a release film and transferring it to the surface of the amorphous cyclic polyolefin resin film 12 is performed. It can also be adopted.

  In the latter case, a pressure-sensitive adhesive solution diluted with an organic solvent is applied onto a release film, heated at 60 to 120 ° C. for about 0.5 to 10 minutes to remove the organic solvent, and the adhesive layer 11 is removed. obtain. Next, after bonding the polarizing film 15 which is the structure of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 to the adhesive layer on the amorphous cyclic polyolefin resin film 12 side, (At around 23 ° C.) If the atmosphere has a relative humidity of around 65%, it is matured for about 5 to 20 days, the cross-linking agent is sufficiently reacted, and then the release film is peeled off to laminate the adhesive layer 11 and the polarizing film 15 You can get a body.

  Moreover, the following method can be mentioned as another method of forming the adhesion layer on a peeling film and transferring this to the surface of the amorphous cyclic polyolefin resin film 12. That is, according to the above, a laminate composed of two layers of a release film and an adhesive layer is obtained. If this is wound in a roll shape and the atmosphere is at room temperature (around 23 ° C.) and relative humidity is around 65%, it is aged for about 5 to 20 days to sufficiently react the crosslinking agent. When wound into a roll, a release film having a release treatment applied to both sides thereof may be used, and the adhesive layer may be sequentially sandwiched between release films, or another release film may be provided on the exposed surface of the adhesive layer. You may stick together. After the above aging is completed, one side of the adhesive layer is exposed (with a release film on one side), and the amorphous cyclic polyolefin resin film 12 side of the polarizing film 15 is bonded to the exposed surface. Then, the polarizing film 10 with an adhesive layer is obtained.

  Here, a peeling film becomes a base material for forming an adhesion layer. During aging or when storing as a laminate of an adhesive layer and a polarizing film, the adhesive layer may be protected from foreign matters such as dust and dirt. As a specific example of the release film, a film made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polyarylate is used as a base material, and a release treatment such as a silicone treatment is performed on the bonding surface of the base material with the adhesive layer. The thing which was given is mentioned.

  When the pressure-sensitive adhesive layer 11 is formed on the surface of the amorphous cyclic polyolefin resin film 12 of the polarizing film 15 having the configuration of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14, the amorphous cyclic polyolefin resin The bonding surface of the resin film 12 is preferably subjected to corona discharge treatment in order to increase the adhesive force with the adhesive layer 11. The corona discharge treatment is a treatment in which a high voltage is applied between the electrodes to discharge and activate the resin film disposed there. The corona discharge treatment is preferably performed with the output set at about 200 to 1,000 W. By setting the output of the corona discharge treatment to 200 W or more, the effect of this treatment becomes remarkable, and the adhesive force between the pressure-sensitive adhesive layer 11 and the amorphous cyclic polyolefin resin film 12 is improved. In addition, by setting the output of the corona discharge treatment to 1,000 W or less, dust that tends to be generated by this treatment is reduced. The effect of corona discharge treatment varies depending on the type of electrode, electrode interval, voltage, humidity, type of resin film used, etc., but for example, the electrode interval is set to 1 to 5 mm and the moving speed is set to about 3 to 20 m / min. It is preferable to do this.

[Optical laminate]
The polarizing film 10 with an adhesive described above can be made into an optical laminate for liquid crystal display by bonding to the glass cell for liquid crystal display on the adhesive layer 11 side. A polarizing film can be bonded to the other surface of the glass cell for liquid crystal display through the same adhesive layer as the adhesive layer 11, but in order to suppress optical defects such as white spots, It is preferable to bond together the polarizing film of the structure where the acetylcellulose type protective film was bonded on both surfaces through the adhesive layer whose gel fraction is lower than the adhesive layer 11 on the opposite side. Thus, the form which bonds a polarizing film on both surfaces of the glass cell for liquid crystal displays through the adhesion layer from which a gel fraction differs may be called "the 1st embodiment of an optical laminated body" below.

  On the other hand, when a polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is bonded to both surfaces of a liquid crystal display glass cell on the amorphous cyclic polyolefin resin film side, Each polarizing film is preferably bonded through an adhesive layer having a high gel fraction and a high cohesive force as described above. In this way, a polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is formed on both surfaces of a glass cell for liquid crystal display via an adhesive layer having a high gel fraction. The form of bonding on the cyclic polyolefin resin film side may be hereinafter referred to as “second embodiment of the optical laminate”.

  Regardless of which form is adopted, as shown in FIG. 3, the optical laminate 30 according to the present invention has a first polarizing layer on one side of the glass cell 35 for liquid crystal display via the first adhesive layer 11. The film 15 is adhered, and the second polarizing film 25 is adhered to the other surface of the glass cell 35 via the second adhesive layer 21. And the 1st polarizing film 15 consists of a structure of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14, and the 1st adhesion layer 11 has a gel fraction of 75 to 95 weight%. The first polarizing film 15 is attached to one side of the glass cell for liquid crystal display 35 via the first adhesive layer 11 on the amorphous cyclic polyolefin resin film 12 side.

  In this optical layered body 30, which of the first polarizing film 15 and the second polarizing film 25 is the front side (viewing side) and which is the back side (backlight side) is arbitrary, The first polarizing film 15 having the amorphous cyclic polyolefin-based resin film 12 is preferably on the back side. In this case, as shown in FIG. 4, it is preferable to provide a surface treatment layer 27 on the outer side of the protective film 24 on the opposite side of the adhesive layer 21 of the second polarizing film 25 on the front side. On the outer side of the protective film 14 in the first polarizing film 15 on the side, a brightness enhancement film 17 similar to that described above with reference to FIG. 2 can be laminated. In FIG. 3, the polarizing film 10 with the adhesive disposed on one side (the lower side of the figure) of the glass cell 35 for liquid crystal display is the same as that shown in FIG. 1, and in FIG. Since the polarizing film 10 with an adhesive disposed on one side (the lower side of the figure) of the glass 35 is the same as that shown in FIG. 2, the same reference numerals are assigned to the same parts as those in FIGS. Thus, detailed description is omitted.

  The glass cell 35 for liquid crystal display contains a glass substrate, and what filled a liquid crystal compound between two glass substrates is normally used for a liquid crystal display device. In addition to TN and STN, various liquid crystal display modes in the glass cell for liquid crystal display 35 are known in this field such as IPS (In-Plane Switching), VA (Vertical Alignment), OCB (Optically Compensated Birefringence). Can be. Examples of the material for the glass substrate include soda lime glass, low alkali glass, and non-alkali glass.

  The surface treatment layer 27 provided on the outer side of the second polarizing film 25 as necessary reduces reflection of light irradiated from an external light source such as a fluorescent lamp in order to improve display characteristics and surface physical properties, This is to improve the visibility of the liquid crystal display device. Specifically, an anti-glare (AG) layer that scatters the reflected light by making the surface uneven, an anti-reflection (AR) layer that uses light interference, a low-reflection (LR) layer that reduces the reflectance by a coating film, etc. Is mentioned. In addition, when a hard coat layer is provided directly on the surface of the polarizing film, or when a hard coat layer is further provided on the antiglare layer, antireflection layer, low reflection layer, etc. The coat layer can also be the surface treatment layer 27.

  The first polarizing film 15 and the second polarizing film 25 are usually disposed through an adhesive layer so that their transmission axes form a predetermined angle, for example, to be orthogonal in the TN mode, IPS mode, and VA mode. Are attached to both surfaces of the glass cell 35 for liquid crystal display.

  The second adhesive layer 21 used for bonding the second polarizing film 25 and the liquid crystal display glass cell 35 is made of an acrylic resin, like the first adhesive layer 11 described above with reference to FIG. It can be obtained by curing an adhesive obtained by blending a crosslinking agent. About an acrylic resin and a crosslinking agent, the description similar to a 1st adhesive is applicable. Moreover, it is preferable to mix | blend the silane type compound also to the adhesive which forms the 2nd adhesion layer 21, like the 1st adhesion layer.

[First Embodiment of Optical Laminate]
The first embodiment of the optical layered body will be described mainly with reference to FIG. 3 and with reference to FIG. 4 as necessary. In this embodiment, the first polarizing film 15 having the structure of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 is provided on the amorphous cyclic polyolefin resin film 12 side. The liquid crystal display glass cell 35 is adhered to one side of the liquid crystal display glass cell 35 through the first adhesive layer 11 having a fraction of 75 to 95% by weight. The second polarizing film 25 to which the acetylcellulose-based protective films 22 and 24 are bonded is pasted via the second adhesive layer 21, and the second adhesive layer 21 has a gel fraction of 30. It is preferable that the content be ˜70% by weight.

  In this embodiment, which of the first polarizing film 15 and the second polarizing film 25 is the front side (viewing side) and which is the back side (backlight side) is arbitrary. It is preferable that the second polarizing film 25 having a structure in which acetylcellulose-based protective films 22 and 24 are bonded to both surfaces of the core 23 is the front side. In this case, as shown in FIG. 4, it is preferable to provide a surface treatment layer 27 on the outer side of the protective film 24 on the side opposite to the adhesive layer 21 of the second polarizing film 25 on the front side. On the outside of the protective film 14 in the first polarizing film 15, a brightness enhancement film 17 similar to that described above with reference to FIG. 2 can be laminated.

  The second polarizing film 25 will be described. The polarizing film is an optical film having a function of emitting polarized light with respect to incident light such as natural light. The polarizing film has a property of absorbing linearly polarized light having a vibration plane in a certain direction and transmitting linearly polarized light having a vibration plane orthogonal to the polarizing film, and an elliptically polarizing film in which a retardation film is laminated on the linear polarizing film. and so on. As the second polarizing film 25, a film including a linear polarizing film is preferably used. Therefore, as a specific example of the polarizer 23 constituting the second polarizing film 25, iodine or a dichroic dye is applied to the uniaxially stretched polyvinyl alcohol resin film, similarly to the polarizer 13 constituting the first polarizing film 15. Examples thereof include a polarizer in which dichroic dyes such as are adsorbed and oriented.

  The polarizer 23 has acetylcellulose-based protective films 22 and 24 bonded to both sides thereof. Specific examples of the acetylcellulose-based protective film include a triacetylcellulose film and a diacetylcellulose film. Among them, a triacetylcellulose film is preferably used. The thickness of the protective films 22 and 24 is usually about 30 to 120 μm.

  In the first embodiment of the optical layered body, the second adhesive layer 21 preferably has a gel fraction of 30 to 70% by weight, more preferably 40% by weight or more and 65% by weight or less. The gel fraction can be measured by the same method as described above for the first pressure-sensitive adhesive. When the gel fraction of the second pressure-sensitive adhesive layer 21 is 30% by weight or more, the adhesiveness under high temperature and high humidity is improved, and there is a possibility that floating or peeling occurs between the glass substrate and the pressure-sensitive adhesive layer. This is preferable because it tends to be low and reworkability tends to improve. On the other hand, when the gel fraction is 70% by weight or less, even if the dimension of the second polarizing film 25 bonded to the adhesive layer changes, the adhesive layer follows the dimensional change and fluctuates. Therefore, it is preferable because there is no difference between the brightness at the peripheral edge and the brightness at the center of the liquid crystal cell, and white spots and color unevenness tend to be suppressed.

  The gel fraction of the second adhesive layer 21 can also be adjusted by adjusting the blending amount of the crosslinking agent in the adhesive. Since the amount of the crosslinking agent that can make the gel fraction of the second adhesive layer 21 30 to 70% by weight varies depending on the type of acrylic resin, etc., the nonvolatile content of the acrylic resin constituting the second adhesive layer 21 is 100% by weight. What is necessary is just to select suitably the compounding quantity of the crosslinking agent with respect to a part (total amount when using 2 or more types) according to the kind of acrylic resin from the range of about 0.1-3 weight part.

  According to the rule that is preferable in the first embodiment of the optical layered body, the gel fraction of the first adhesive layer 11 is at least 5% by weight greater than the gel fraction of the second adhesive layer 21, More preferably, the difference between the two is 10% by weight or more, more preferably 15% by weight or more.

  In the second adhesive layer 21 constituting the first embodiment of the optical layered body, the structural unit derived from the (meth) acrylic acid alkyl ester described as the acrylic resin is used as a main component. In addition to an acrylic resin containing a structural unit derived from a monomer having a polar functional group, particularly an acrylic resin having a weight average molecular weight (Mw) of 1,000,000 to 2,000,000 (referred to as the first acrylic resin), a second different from that It is also effective to use a combination of acrylic resins. In this case, the second acrylic resin is mainly composed of a structural unit derived from (meth) acrylic acid alkyl ester, and the weight average molecular weight (Mw) in terms of standard polystyrene by GPC is usually in the range of 50,000 to 500,000. preferable. When the weight average molecular weight is 50,000 or more, the adhesiveness under high temperature and high humidity is improved, and the possibility of floating or peeling between the glass substrate and the adhesive layer tends to be reduced. It is preferable from the tendency to improve the property, and when the weight average molecular weight is 500,000 or less, even if the dimension of the second polarizing film 25 bonded to the adhesive layer changes, the dimensional change Since the adhesive layer follows and fluctuates, there is no difference between the brightness of the peripheral edge of the liquid crystal cell and the brightness of the central portion, which is preferable because white spots and color unevenness tend to be suppressed.

  When the first acrylic resin and the second acrylic resin are mixed and used, the second acrylic resin is usually 5 to 50 parts by weight, more preferably about 20 to 40 parts by weight based on the total of 100 parts by weight of both. It is preferable that the ratio is as follows. If the amount of the second acrylic resin relative to 100 parts by weight of the whole acrylic resin is 5 parts by weight or more, even if the size of the second polarizing film 25 bonded to the adhesive layer changes, the size changes. Since the pressure-sensitive adhesive layer follows and fluctuates, there is no difference between the brightness of the peripheral edge of the liquid crystal cell and the brightness of the central portion, which is preferable because white spots and color unevenness tend to be suppressed. When the amount of the acrylic resin is 50 parts by weight or less, the adhesiveness under high temperature and high humidity is improved, and the possibility of occurrence of floating or peeling between the glass substrate and the adhesive layer tends to be low, and This is preferable because reworkability tends to be improved.

  Although the thickness of the 2nd adhesion layer 21 is not specifically limited, Usually, it is preferable that it is 30 micrometers or less, and it is preferable that it is 10 micrometers or more. If the thickness of the adhesive layer is 30 μm or less, the adhesiveness under high temperature and high humidity is improved, and there is a tendency that the possibility of floating or peeling between the glass substrate and the adhesive layer tends to be reduced. Since the adhesive layer tends to improve, and the thickness is 10 μm or more, even if the size of the polarizing film bonded thereto changes, the adhesive layer follows the change in size and fluctuates. The difference between the brightness of the peripheral edge of the liquid crystal cell and the brightness of the central portion is eliminated, and it is preferable because white spots and color unevenness tend to be suppressed. The thickness of the second adhesive layer 21 is more preferably 25 μm or less, and more preferably 15 μm or more.

[Second Embodiment of Optical Laminate]
Next, the second embodiment of the optical layered body will be described mainly with reference to FIG. 3 and with reference to FIG. 4 as necessary. In this embodiment, the first polarizing film 15 having the structure of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 is provided on the amorphous cyclic polyolefin resin film 12 side. It is laminated on one side of the liquid crystal display glass cell 35 through the first adhesive layer 11 having a fraction of 75 to 95% by weight, and an amorphous cyclic polyolefin resin on the other side of the liquid crystal display glass cell 35. The second polarizing film 25 having the structure of film 22 / polarizer 23 / protective film 24 is provided on the amorphous cyclic polyolefin resin film 22 side, and the gel fraction is 75 to 95% by weight. Laminate via the second adhesive layer 21.

  About the 2nd polarizing film 25 in this form, the description similar to having described the polarizing film 15 previously with reference to FIG. 1 is applicable. The same description as that described for the adhesive layer 11 applies to the second adhesive layer 21 with reference to FIG.

  In this optical layered body, the front and back surfaces of the glass cell 35 for liquid crystal display basically have a symmetrical structure. Therefore, whichever is the front side (viewing side) and which is the back side (backlight side). In FIG. 4, the second polarizing film 25 is the front side. And it is preferable to provide the surface treatment layer 27 in the outer side of the protective film 24 on the opposite side to the adhesion layer 21 in the 2nd polarizing film 25 used as the front side. Moreover, the brightness enhancement film 17 can be laminated | stacked on the outer side of the protective film 14 in the 1st polarizing film 15 used as the back side.

[Method for producing optical laminate]
The optical laminated body shown in FIG. 3 has a configuration of an amorphous cyclic polyolefin-based resin film 12 / a polarizer 13 / a protective film 14 via a first adhesive layer 11 on one side of a glass cell 35 for liquid crystal display. The first polarizing film 15 is adhered on the amorphous cyclic polyolefin-based resin film 12 side, and the second polarizing film is disposed on the other surface of the liquid crystal display glass cell 35 via the second adhesive layer 21. It can be manufactured by the method of sticking 25.

  And in manufacture of 1st embodiment of an above-described optical laminated body, the 1st adhesion layer 11 is prepared so that the gel fraction may become 75 to 95 weight%, and the amorphous of the 1st polarizing film 15 is used. The second pressure-sensitive adhesive layer 21 is provided on the surface of the conductive cyclic polyolefin-based resin film 12 so that the gel fraction thereof is 30 to 70% by weight and provided on one side of the second polarizing film 25. A method of bonding the first polarizing film 15 and the second polarizing film 25 to both surfaces of the liquid crystal display glass cell 35 can be employed. As shown in FIG. 4, when the brightness enhancement film 17 is provided outside the protective film 14 of the first polarizing film 15, an amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 is formed. It is advantageous to bond the brightness enhancement film 17 to the outside of the protective film 14 via an adhesive or the like at the stage of one polarizing film 15. When the surface treatment layer 27 is provided on one side of the second polarizing film 25, the second polarizing film 25 is prepared with the surface treatment layer 27 provided on one side of the one protective film 24. In addition, a method of adhering this to one side of the glass cell 35 for liquid crystal display via the second adhesive layer 21 can be adopted, and after the optical laminate is produced, finally, the surface treatment layer 27 is formed. Although the method of laminating the formed film on the surface of the second polarizing film 25 can be employed, the former method is generally advantageous.

  Specifically, for example, the optical laminate of the first embodiment can be produced by the following method. First, in accordance with the method shown in the method for producing a polarizing film with an adhesive, the first polarizing film 15 having the structure of the amorphous cyclic polyolefin-based resin film 12 / the polarizer 13 / the protective film 14 (if necessary) The first pressure-sensitive adhesive layer 11 is formed on the surface of the amorphous cyclic polyolefin-based resin film 12 (the brightness enhancement film 17 is provided on the outside of the protective film 14), and the first pressure-sensitive adhesive polarizing film 10 is produced. To do. Separately, the surface of the one-side protective film 22 is also applied to the second polarizing film 25 (if the second polarizing film 25 has a surface treatment layer 27, the surface opposite to the surface treatment layer), according to the above. The second pressure-sensitive adhesive layer 21 is formed by the above-described method to produce the second pressure-sensitive adhesive polarizing film 20. The first polarizing film 10 with the pressure-sensitive adhesive and the second polarizing film 20 with the pressure-sensitive adhesive are bonded to each surface of the glass cell 35 for liquid crystal display on the respective adhesive layer side.

  Alternatively, the following method can be employed. First, the 1st adhesion layer 11 is formed on a peeling film by the method according to the above, and the 2nd adhesion layer 21 is formed on another peeling film. The first adhesive layer 11 is transferred onto the amorphous cyclic polyolefin-based resin film 12 of the first polarizing film 15, and the second adhesive layer is transferred onto the second polarizing film 25. Thereafter, the release film is peeled off to obtain a laminate of the first adhesive layer 11 and the first polarizing film 15 and a laminate of the second adhesive layer 21 and the second polarizing film 25. After bonding the first adhesive layer 11 to one side of the liquid crystal display glass cell 35 and the second adhesive layer 21 to the other side of the liquid crystal display glass cell 35, the surface treatment layer 27 is used as the second polarizing film. Laminated on the surface of 25. In this case, for example, a film on which the surface treatment layer 27 is formed is prepared, and this is bonded to the surface of the second polarizing film 25.

  In the second embodiment of the optical laminate, the second polarizing film 25 employs an amorphous cyclic polyolefin resin film 22 / polarizer 23 / protective film 24, which is used as the second adhesive film 25. As the layer 21, a layer having a gel fraction of 75 to 95% by weight is adopted, and other layers can be produced by a method according to the above.

[Set of polarizing film]
The set of polarizing films according to the present invention comprises the structure of amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 described above as the first embodiment of the optical laminate with reference to FIG. On both surfaces of the first polarizing film 10 with the adhesive having the first polarizing film 15 and the first adhesive layer 11 provided on the amorphous cyclic polyolefin-based resin film 12 side, and the polarizer 23. It consists of the 2nd polarizing film 25 with the adhesive which has the 2nd polarizing film 25 with which the acetylcellulose type protective films 22 and 24 were bonded, and the 2nd adhesive layer 21 provided in the single side | surface. The first adhesive layer 11 has a gel fraction of 75 to 95% by weight, and the second adhesive layer 21 has a gel fraction of 30 to 70% by weight.

[Production method of polarizing film set]
Specifically, this set of polarizing films is the amorphous cyclic polyolefin resin film 12 side of the first polarizing film 15 having the structure of amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14. The first pressure-sensitive adhesive layer 11 is provided to form a first polarizing film 10 with a pressure-sensitive adhesive, and separately, a second polarizing film 25 in which acetylcellulose-based protective films 22 and 24 are bonded to both surfaces of the polarizer 22. It can manufacture by the method of providing the 2nd adhesion layer in the single side | surface, and setting it as the 2nd polarizing film 20 with an adhesive. As shown in FIG. 4, when the brightness enhancement film 17 is provided on the first polarizing film 15 side, the first polarizing film 15 having a configuration of the amorphous cyclic polyolefin resin film 12 / the polarizer 13 / the protective film 14. At this stage, it is advantageous to bond the brightness enhancement film 17 to the outside of the protective film 14 via an adhesive or the like. When the surface treatment layer 27 is provided on one side of the second polarizing film 25, it is advantageous to produce the second polarizing film 25 in a state where the surface treatment layer 27 is provided on one side of the one protective film 24. It is. The first pressure-sensitive adhesive layer 11 is prepared so that its gel fraction is 75 to 95% by weight, provided on the surface of the amorphous cyclic polyolefin-based resin film 12 of the first polarizing film 15, and the second pressure-sensitive adhesive layer 11. The layer 21 is prepared so that the gel fraction is 30 to 70% by weight, and one side of the second polarizing film 25 (if the second polarizing film 25 has a surface treatment layer 27, the surface treatment On the opposite side of the layer.

  Each pressure-sensitive adhesive layer can be provided by a method in which a solution of a pressure-sensitive adhesive is directly applied to the surface of the amorphous cyclic polyolefin resin film 12 of the first polarizing film 15 or one surface of the second polarizing film 25. As described above as an example of the method for producing a polarizing film with an adhesive and the method for producing an optical laminate, an adhesive layer is formed by applying a solution of an adhesive on a release film and removing the solvent. It is advantageous to provide it by a method of transferring it to the surface of each polarizing film. In the latter case, the first adhesive layer 11 is prepared so that the gel fraction is 75 to 95% by weight, and an adhesive diluted with an organic solvent is applied onto the release film to remove the organic solvent. In this state, the first polarizing film 15 is bonded to the surface of the amorphous cyclic polyolefin resin film 12. The second adhesive layer 21 is prepared such that the gel fraction is 30 to 70% by weight, and an adhesive diluted with an organic solvent is applied onto the release film, and the organic solvent is removed. The first polarizing film 25 is bonded to one side. In any case, the adhesive layer is aged for a sufficient period of time before or after being applied to the polarizing film, and is allowed to react with the crosslinking agent.

  In addition, the 1st polarizing film 15 which consists of a structure of the amorphous cyclic polyolefin resin film 12 / polarizer 13 / protective film 14 demonstrated as 2nd embodiment of an optical laminated body, and its amorphous cyclic polyolefin type | system | group It consists of the structure of the 1st polarizing film 10 with an adhesive which has the 1st adhesion layer 11 provided in the resin film 12 side, and the amorphous cyclic polyolefin resin film 22 / polarizer 23 / protective film 24. The combination of the 2nd polarizing film 25 with an adhesive which has the 2nd polarizing film 25 and the 2nd adhesion layer 21 provided in the single side | surface can also become a set of another polarizing film. However, in this case, the two polarizing films with adhesives 10 and 20 basically have the same configuration except when an additional layer such as a surface treatment layer or a brightness enhancement film is provided. It will be unnecessary.

[Liquid Crystal Display]
The optical layered body of the present invention is advantageously used as a transmissive liquid crystal display device. In this case, if it is the structure shown in FIG. 3, the outer side of the 1st polarizing film 15 or the outer side of the 2nd polarizing film 25, Preferably it is on the opposite side to the glass cell 35 for liquid crystal displays of the 1st polarizing film 15. In the structure shown in FIG. 4 provided with a backlight, a backlight is provided on the side of the brightness enhancement film 17 opposite to the glass cell 35 for liquid crystal display, so that a liquid crystal display device is obtained.

  In the optical laminate of the present invention, or in the state where the set of polarizing films is bonded to the glass cell for liquid crystal display, the adhesive residue remains on the surface of the glass substrate in contact with the adhesive layer even after the polarizing film is peeled off. Since almost no fogging or fogging occurs, it is easy to attach the polarizing film again to the glass cell for liquid crystal display after peeling off the polarizing film. That is, it is excellent in so-called reworkability.

  The liquid crystal display device formed from this optical laminate includes, for example, notebook type, desktop type, personal computer display including PDA (Personal Digital Assistance), television, in-vehicle display, electronic dictionary, digital camera, digital video It can be used for cameras, electronic desk calculators, watches, etc.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited by these examples. In the examples, “parts” and “%” representing the amount used or content are based on weight unless otherwise specified.

The nonvolatile content of the acrylic resin is a value measured by a method according to JIS K 5407. Specifically, the adhesive solution was taken in a petri dish at an arbitrary weight, and the residual non-volatile content after drying for 2 hours at 115 ° C. in an explosion-proof oven was expressed as a percentage of the weight of the solution first measured. It is. For the measurement of the weight average molecular weight and number average molecular weight, two “TSK gel GMH _HR- H (S)” manufactured by Tosoh Corp. are connected in series to the GPC device, and tetrahydrofuran is used as the eluent. The standard polystyrene conversion was performed under the conditions of a sample concentration of 5 mg / ml, a sample introduction amount of 100 μl, a temperature of 40 ° C., and a flow rate of 1 ml / min.

  First, an example of producing an acrylic resin is shown.

[Polymerization Example 1]
A reactor equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer and a stirrer was charged with a mixed solution of 169.8 parts of ethyl acetate, 97.0 parts of butyl acrylate and 3.0 parts of acrylic acid, and the inside of the apparatus with nitrogen gas The air was replaced with oxygen and the internal temperature was raised to 55 ° C., and then a total solution of 0.14 part of azobisisobutyronitrile (polymerization initiator) dissolved in 5 parts of ethyl acetate was added. . Thereafter, the inner temperature was maintained at 54 to 56 ° C. for 12 hours, and finally ethyl acetate was added to adjust the concentration of the acrylic resin to 20%. The obtained acrylic resin had a polystyrene-equivalent weight average molecular weight Mw by GPC of 1,540,000 and Mw / Mn of 4.69. This is designated as acrylic resin A1.

[Polymerization Example 2]
20% concentration acrylic resin solution in the same manner as in Polymerization Example 1, except that the monomer composition was changed to 98.7 parts butyl acrylate, 1.1 parts acrylic acid, and 0.2 parts 2-ethylhexyl acrylate. Got. The obtained acrylic resin had a polystyrene-equivalent weight average molecular weight Mw of 1,390,000 and Mw / Mn of 3.53 by GPC. This is designated as acrylic resin A2.

[Polymerization Example 3]
A reactor equipped with a cooling pipe, a nitrogen introduction pipe, a thermometer, and a stirrer was charged with a mixed solution of 81.8 parts of ethyl acetate, 98.9 parts of butyl acrylate and 1.1 parts of acrylic acid, and the inside of the apparatus with nitrogen gas After the air was replaced and oxygen-free, the internal temperature was raised to 55 ° C., and then a total solution of 0.14 parts of azobisisobutyronitrile (polymerization initiator) dissolved in 10 parts of ethyl acetate was added. . One hour after the addition of the initiator, while adding ethyl acetate continuously to the reactor at an addition rate of 17.3 parts / hr so that the concentration of the acrylic resin excluding the monomer was 35%, the internal temperature was 54 to 56 ° C. For 12 hours, and finally ethyl acetate was added to adjust the concentration of the acrylic resin to 20%. The obtained acrylic resin had a polystyrene equivalent weight average molecular weight Mw of 1,670,000 and Mw / Mn of 4.4 by GPC. This is designated as acrylic resin A3.

[Polymerization Example 4]
In the same reactor used in Polymerization Example 1, 222 parts of ethyl acetate, 35 parts of butyl acrylate, 44 parts of butyl methacrylate, 20 parts of methyl acrylate and 1 part of 2-hydroxyethyl acrylate were charged with nitrogen gas. After the air in the apparatus was replaced, the temperature was raised so that the internal temperature became 75 ° C. Next, after adding a total amount of 0.55 parts of azobisisobutyronitrile (polymerization initiator) dissolved in 12.5 parts of ethyl acetate, the temperature was kept for 8 hours while maintaining the internal temperature at 69-71 ° C. The reaction was complete. The resulting acrylic resin had a polystyrene equivalent weight average molecular weight of 90,000 by GPC. This is designated as acrylic resin A4.

  Next, the example which manufactured the adhesive using the acrylic resin manufactured above is shown. Here, the following were used as the crosslinking agent and the silane compound (both are trade names).

Cross-linking agent Coronate L: Trimethylolpropane adduct of tolylene diisocyanate in ethyl acetate solution (solid content concentration 75%), obtained from Nippon Polyurethane Industry Co., Ltd.
TAZM: trimethylolpropane tri-β-aziridinylpropionate (liquid), obtained from Mutual Pharmaceutical Co., Ltd.

Silane compounds
X-41-1805: Silane oligomer having a mercapto group (liquid), obtained from Shin-Etsu Chemical Co., Ltd.

[Production Example 1 of adhesive]
To 100 parts of the non-volatile content of the acrylic resin A1 obtained in Polymerization Example 1, 5 parts of the cross-linking agent “Coronate L” and 0.1 part of the silane compound “X-41-1805” were mixed, A pressure-sensitive adhesive solution was obtained. The pressure-sensitive adhesive solution was dried using an applicator on the release-treated surface of a polyethylene terephthalate film (trade name “PET 3811”, obtained from Lintec Co., Ltd .; called a separator) that had been subjected to a release treatment. Was applied to a thickness of 15 μm and dried at 100 ° C. for 1 minute to obtain a sheet-like pressure-sensitive adhesive. This is referred to as adhesive 1.

[Production Example 2 of adhesive]
To 100 parts of the non-volatile content of the acrylic resin A2 obtained in Polymerization Example 2, 1.5 parts of the cross-linking agent “Coronate L” and 0.1 part of the silane compound “X-41-1805” were mixed. Thus, an adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to the release treatment surface of the separator similar to the above using an applicator so that the thickness after drying was 25 μm, and dried at 100 ° C. for 1 minute to obtain a sheet-shaped pressure-sensitive adhesive. Got. This is designated as adhesive 2.

[Production Example 3 of adhesive]
Acrylic resin A3 obtained in Polymerization Example 3 was mixed in a proportion of 70 parts as a nonvolatile component, and acrylic resin A4 obtained in Polymerization Example 4 was mixed in a proportion of 30 parts as a nonvolatile component to obtain an ethyl acetate solution of the acrylic resin. To 100 parts of the solid content of the resulting solution, 2.3 parts of the cross-linking agent “Coronate L” and 0.1 part of the silane compound “X-41-1805” are mixed to form an adhesive. It was set as the solution. This pressure-sensitive adhesive solution was applied to the release treatment surface of the separator similar to the above using an applicator so that the thickness after drying was 25 μm, and dried at 100 ° C. for 1 minute to obtain a sheet-shaped pressure-sensitive adhesive. Got. This is referred to as adhesive 3.

[Production Example 4 of adhesive]
For 100 parts of the non-volatile content of the acrylic resin A3 obtained in Polymerization Example 3, 2 parts of the cross-linking agent “Coronate L”, 0.02 part of “TAZM”, and silane compound “X-41-1805” Was mixed to give an adhesive solution. This pressure-sensitive adhesive solution was applied to the release treatment surface of the same separator as described above using an applicator so that the thickness after drying was 15 μm, and dried at 100 ° C. for 1 minute to obtain a sheet-shaped pressure-sensitive adhesive. Got. This is referred to as an adhesive 4.

  About the adhesives 1-4, the composition of the acrylic resin, the compounding quantity of a crosslinking agent and a silane type compound, the coating film thickness of the obtained adhesive, and the gel fraction were put together in Table 1.

  Next, the Example and comparative example which produced the polarizing film with an adhesive and produced the optical laminated body by applying it to a glass substrate are shown. Here, steps until the optical layered body 30 is obtained will be described with reference to the reference numerals shown in FIG. First, the 1st polarizing film which is a structure of a norbornene-type resin film / polyvinyl alcohol-type polarizer / triacetyl cellulose protective film is stuck on one side of the glass cell for liquid crystal displays, and a triacetyl cellulose protective film / The example which sticks the 2nd polarizing film which is a structure of a polyvinyl-alcohol-type polarizer / triacetylcellulose protective film is shown.

[Example 1]
(A) Preparation of polarizing film with adhesive A first polarizing film 15 having a configuration of norbornene-based resin film / polyvinyl alcohol-based polarizer / triacetyl cellulose protective film is prepared, and output to the surface of the norbornene-based resin film 12 is output. After performing corona discharge treatment under the conditions of 600 W and moving speed of 10 m / min, a laminator is used on the corona discharge treatment surface, and the sheet-like separator-attached pressure-sensitive adhesive 1 (gel) Are bonded on the pressure-sensitive adhesive side and further aged for 10 days under the conditions of a temperature of 23 ° C. and a relative humidity of 65%, and the norbornene-based resin film 12 of the first polarizing film 15 is bonded. The 1st adhesion layer 11 was formed in the surface, and it was set as the 1st polarizing film 10 with an adhesive.

  Separately, a second polarizing film 25 having a structure of triacetyl cellulose protective film / polyvinyl alcohol polarizer / triacetyl cellulose protective film and having an antireflection layer formed on the surface of one protective film is prepared, and its reflection Using a laminator on the surface of the protective film on which the prevention layer is not provided, the sheet-like pressure-sensitive adhesive 3 with a separator shown in the production example of the pressure-sensitive adhesive (gel fraction 61.8%, film thickness 25 μm) And aged for 10 days under the conditions of a temperature of 23 ° C. and a relative humidity of 65% to form the second adhesive layer 21 on the one-side protective film 22 surface of the second polarizing film 25, It was set as the 2nd polarizing film 20 with an adhesive.

(B) Production of Optical Laminate On one surface of a glass substrate for liquid crystal display [“1737” (trade name) manufactured by Corning Co., Ltd.] 35, the first polarizing film 10 with the pressure-sensitive adhesive is removed from the pressure-sensitive adhesive layer 11. The separator was peeled off and bonded, and the second polarizing film 20 with the pressure-sensitive adhesive was peeled off from the pressure-sensitive adhesive layer 21 and bonded to the other surface of the glass substrate. At this time, the first polarizing film 15 and the second polarizing film 25 were attached so as to be crossed Nicols. Thus, the antireflection layer / second polarizing film 25 / second pressure-sensitive adhesive layer 21 / glass substrate 35 / first pressure-sensitive adhesive layer 11 / (norbornene resin film 12 / polarizer 13 / protective film 14). An optical laminate 30 in which one polarizing film 15) was sequentially laminated was produced. Each of the two polarizing films was a square of 30 cm × 22 cm (15 type).

(C) Evaluation of durability, etc. The above optical laminate was subjected to a heat resistance test for 96 hours under dry conditions at a temperature of 80 ° C., and then the appearance of white spots was visually observed. In addition, when the heat resistance test is performed under the same conditions as above, when the heat and humidity resistance test is performed for 96 hours at a temperature of 60 ° C. and a relative humidity of 90%, the temperature is decreased to −30 ° C. from the state heated to 70 ° C. Then, the process of raising the temperature to 70 ° C. is defined as one cycle (one hour), and each of the cases where a heat shock resistance test (abbreviated as “HS resistance test” in the table) is repeated for 100 cycles is performed after the test. Durability in the body was evaluated. The results are classified in the following manner and are summarized in Table 2.

<Development of white spots>
The appearance of white spots when light was incident from the first polarizing film side was evaluated in the following four stages.
A: No white spots are observed.
○: White spots are hardly noticeable.
Δ: White spots are slightly noticeable.
X: White spots are noticeable.

<Durability evaluation>
Durability was evaluated in the following four stages for each of the optical laminates after the heat resistance test, the moist heat resistance test, and the heat shock resistance test.
A: No change in appearance such as floating, peeling or foaming is observed.
○: Almost no change in appearance such as floating, peeling or foaming.
Δ: Appearance changes such as floating, peeling and foaming are slightly noticeable.
X: Remarkable changes in appearance such as floating, peeling, foaming, etc.

(D) Evaluation of reworkability A test piece having a size of 25 mm x 150 mm was cut from each of the two types of polarizing films with adhesives prepared in (a). The test piece was attached to a glass cell substrate for liquid crystal display using a sticking device ["Lami Packer" (trade name) manufactured by Fuji Plastics Co., Ltd.] at a temperature of 50 ° C. and a pressure of 5 kg / cm ² (490.3 kPa). Autoclaving was performed for 20 minutes. Next, after heat treatment at 70 ° C. for 2 hours and subsequent storage in an oven at 50 ° C. for 48 hours, a polarizing film was removed from the adhesion test piece at 300 mm / mm in an atmosphere at a temperature of 23 ° C. and a relative humidity of 50%. It peeled in the direction of 180 degree at the speed | rate of the minute, and observed the surface of the glass plate. As a result, both of the two types of polarizing films with pressure-sensitive adhesive showed good reworkability in a state where no adhesive residue was observed on the glass plate surface and no cloudiness or the like was observed.

[Example 2]
The pressure-sensitive adhesive to be bonded to the surface of the norbornene-based resin film 12 of the first polarizing film 15 having the configuration of norbornene-based resin film / polyvinyl alcohol-based polarizer / triacetyl cellulose protective film is shown in the production example of the previous pressure-sensitive adhesive. A polarizing film with a pressure-sensitive adhesive was prepared in the same manner as in Example 1 except that the pressure-sensitive adhesive with a sheet-like separator 2 (gel fraction: 82.9%, film thickness: 25 μm) was used, and an optical laminate was further prepared. . This optical laminate was evaluated in the same manner as in Example 1 (c), and the results are shown in Table 2. Moreover, evaluation of rework property is carried out similarly to (d) of Example 1 about the polarizing film with an adhesive which applied the adhesive 2 with a separator to the norbornene-type resin film 12 surface of the 1st polarizing film 15 produced here. As a result, no remnant residue was observed on the surface of the glass plate, and good reworkability was exhibited with almost no cloudiness or the like.

[Example 3]
An adhesive that is bonded to the surface of the norbornene-based resin film 12 of the first polarizing film 15 and an adhesive that is bonded to the surface of the protective film on the side where the antireflection layer of the second polarizing film 25 is not provided are both adhesive. An optical laminate was prepared and evaluated in the same manner as in Example 1 except that the pressure-sensitive adhesive 1 (gel fraction: 80.2%, film thickness: 15 μm) shown in Production Example 1 was used. The results are also shown in Table 2.

[Comparative Example 1]
An adhesive that is bonded to the surface of the norbornene-based resin film 12 of the first polarizing film 15 and an adhesive that is bonded to the surface of the protective film on the side where the antireflection layer of the second polarizing film 25 is not provided are both adhesive. An optical laminate was prepared and evaluated in the same manner as in Example 1 except that the pressure-sensitive adhesive 3 (gel fraction 61.8%, film thickness 25 μm) shown in Production Example 1 was used. The results are also shown in Table 2.

[Comparative Example 2]
The pressure-sensitive adhesive to be bonded to the surface of the norbornene-based resin film 12 of the first polarizing film 15 is the pressure-sensitive adhesive 3 (gel fraction 61.8%, film thickness 25 μm) shown in the pressure-sensitive adhesive production example. The adhesive to be bonded to the surface of the protective film on the side where the antireflection layer of the film 25 is not provided is the adhesive 1 (gel fraction 80.2%, film thickness 15 μm) shown in the adhesive production example. Were produced and evaluated in the same manner as in Example 1. The results are also shown in Table 2.

  The first pressure-sensitive adhesive layer provided on the amorphous cyclic polyolefin-based resin film side of the first polarizing film having the amorphous cyclic polyolefin-based resin film is a pressure-sensitive adhesive 1 having a high gel fraction and thus a high cohesive force. In Examples 1 to 3 composed of the pressure-sensitive adhesive 2, since this pressure-sensitive adhesive layer was bonded to the amorphous cyclic polyolefin-based resin film, the adhesive force was increased and high durability was exhibited. Moreover, the 2nd adhesion layer provided in the said cellulose-type protective film side of the normal polarizing film (2nd polarizing film) which has a cellulose-type protective film is low gel fraction, Therefore, it is the adhesive 3 with a small cohesion force. Since the constructed Examples 1 and 2 can relieve the stress between the second adhesive layer and the glass surface, white spots can also be suppressed.

  In Example 3 using the pressure-sensitive adhesive 1 having a high gel fraction and a large cohesive force on the second polarizing film side, white spots are slightly conspicuous with the dimensional change due to heat of the second polarizing film. However, depending on the application and the needs of LCD panel manufacturers, it was able to withstand sufficient use.

  On the other hand, in both of the pressure-sensitive adhesive layers, the pressure-sensitive adhesive 3 having a low cohesive force is used in the optical laminated body of Comparative Example 1 in which the gel fraction is low and thus the pressure-sensitive adhesive 3 having a low cohesive force is used. For this reason, good results were obtained in white spots, but the durability was inferior. On the other hand, in Comparative Example 2 using the adhesive 3 with a low gel fraction on the first polarizing film side and the adhesive 1 with a high gel fraction on the second polarizing film side, Due to the pressure-sensitive adhesive 3 having a small cohesive force used, a result inferior in durability was shown.

  Next, an example in which a polarizing film having a configuration of norbornene-based resin film / polyvinyl alcohol-based polarizer / triacetyl cellulose protective film is attached to both surfaces of a liquid crystal display glass cell will be described.

[Example 4]
(A) Preparation of polarizing film with adhesive A first polarizing film 15 having a configuration of norbornene-based resin film / polyvinyl alcohol-based polarizer / triacetyl cellulose protective film is prepared, and output to the surface of the norbornene-based resin film 12 is output. After performing corona discharge treatment under the conditions of 600 W and moving speed of 10 m / min, a laminator is used on the corona discharge treatment surface, and the sheet-like separator-attached pressure-sensitive adhesive 1 (gel) Are bonded on the pressure-sensitive adhesive side and further aged for 10 days under the conditions of a temperature of 23 ° C. and a relative humidity of 65%, and the norbornene-based resin film 12 of the first polarizing film 15 is bonded. The 1st adhesion layer 11 was formed in the surface, and it was set as the 1st polarizing film 10 with an adhesive.

  Separately, a second polarizing film 25 having a configuration of norbornene-based resin film / polyvinyl alcohol-based polarizer / triacetyl cellulose protective film, and having an antireflection layer formed on the surface of the triacetyl cellulose protective film is prepared. After the corona discharge treatment is performed on the surface of the resin-based resin film 22 under the conditions of an output of 600 W and a moving speed of 10 m / min, a laminator is used on the corona discharge treatment surface, and the sheet shape shown in the previous production example of the pressure-sensitive adhesive Adhesive 1 with a separator (gel fraction 80.2%, film thickness 15 μm) was bonded on the adhesive side, and further aged for 10 days under conditions of a temperature of 23 ° C. and a relative humidity of 65%. A second pressure-sensitive adhesive layer 21 is formed on the one-side norbornene-based protective film 22 surface of the film 25, and the second pressure-sensitive adhesive polarizing film 20 and did.

(B) Production of Optical Laminate On one surface of a glass substrate for liquid crystal display [“1737” (trade name) manufactured by Corning Co., Ltd.] 35, the first polarizing film 10 with the pressure-sensitive adhesive is removed from the pressure-sensitive adhesive layer 11. The separator was peeled off and bonded, and the second polarizing film 20 with the pressure-sensitive adhesive was peeled off from the pressure-sensitive adhesive layer 21 and bonded to the other surface of the glass substrate. At this time, the first polarizing film 15 and the second polarizing film 25 were attached so as to be crossed Nicols. Thus, the antireflection layer / (the protective film 24 / the polarizer 23 / the second polarizing film 25 having the norbornene-based resin film 22) / the second adhesive layer 21 / the glass substrate 35 / the first adhesive layer 11 /. An optical layered body 30 in which (the first polarizing film 15 having the configuration of norbornene-based resin film 12 / polarizer 13 / protective film 14) was sequentially laminated was produced. Each of the two polarizing films was a square of 30 cm × 22 cm (15 type).

(C) Evaluation of durability, etc. The optical laminate produced above was evaluated by the same method as in Example 1 (c), and the results are summarized in Table 3.

(D) Reworkability evaluation Reworkability was evaluated for each of the two types of polarizing films with pressure-sensitive adhesives prepared in (a) by the same method as in (d) of Example 1. As a result, both of the two types of polarizing films with pressure-sensitive adhesive showed good reworkability in a state where no adhesive residue was observed on the glass plate surface and no cloudiness or the like was observed.

[Example 5]
The pressure-sensitive adhesive to be bonded to the surfaces of the norbornene-based resin films 12 and 22 of the first polarizing film 15 and the second polarizing film 25 is the pressure-sensitive adhesive 4 with a sheet separator (gel) shown in the previous pressure-sensitive adhesive production example. A polarizing film with an adhesive was produced in the same manner as in Example 4 except that the fraction was changed to 75.5% and the film thickness was 15 μm, and an optical laminate was further produced. This optical laminate was evaluated in the same manner as in Example 4 (c), and the results are also shown in Table 3. Further, the reworkability was evaluated in the same manner as in Example 4 (d) for each of the two types of polarizing films with pressure-sensitive adhesives produced here. As a result, both of the two types of polarizing films with pressure-sensitive adhesive showed good reworkability in a state where no adhesive residue was observed on the glass plate surface and no cloudiness or the like was observed.

[Comparative Example 3]
The pressure-sensitive adhesive to be bonded to the surface of the norbornene-based resin film 22 of the second polarizing film 25 is the sheet-shaped pressure-sensitive adhesive 3 with a separator shown in the previous pressure-sensitive adhesive production example (gel fraction 61.8%, film thickness 25 μm). The polarizing film with the pressure-sensitive adhesive was prepared in the same manner as in Example 4 except that the optical laminated body was further changed. This optical laminate was evaluated in the same manner as in Example 4 (c), and the results are shown in Table 3. Moreover, about the polarizing film with an adhesive newly produced here, rework property was evaluated similarly to (d) of Example 4. FIG. As a result, good reworkability was exhibited in a state in which no adhesive residue was observed on the glass plate surface and almost no fogging was observed.

[Comparative Example 4]
The pressure-sensitive adhesive to be bonded to the surface of the norbornene-based resin film 12 of the first polarizing film 15 is the sheet-shaped pressure-sensitive adhesive 3 with a separator shown in the previous pressure-sensitive adhesive production example (gel fraction 61.8%, film thickness 25 μm). The polarizing film with the pressure-sensitive adhesive was prepared in the same manner as in Example 4 except that the optical laminated body was further changed. This optical laminate was evaluated in the same manner as in Example 4 (c), and the results are shown in Table 3. Moreover, about the polarizing film with an adhesive newly produced here, rework property was evaluated similarly to (d) of Example 4. FIG. As a result, good reworkability was exhibited in a state in which no adhesive residue was observed on the glass plate surface and almost no fogging was observed.

[Comparative Example 5]
The pressure-sensitive adhesive 3 with a separator in the same sheet form as that used in Comparative Examples 3 and 4 was used for the adhesive to be bonded to the surfaces of the norbornene-based resin films 12 and 22 of the first polarizing film 15 and the second polarizing film 25, respectively. A polarizing film with an adhesive was produced in the same manner as in Example 4 except that the gel fraction was changed to 61.8% and the film thickness was 25 μm, and an optical laminate was further produced. This optical laminate was evaluated in the same manner as in Example 4 (c), and the results are also shown in Table 3.

  When laminating a polarizing film having an amorphous cyclic polyolefin resin film on both sides of a glass cell for liquid crystal display via the adhesive layer on the amorphous cyclic polyolefin resin film side, Examples 4 and 5, which were composed of the pressure-sensitive adhesive 1 or pressure-sensitive adhesive 4 having a high rate and thus a high cohesive strength, showed an increased adhesive force and high durability. On the other hand, Comparative Examples 3 to 5 in which one adhesive layer or both adhesive layers were composed of the adhesive 3 having a low gel fraction and thus a small cohesive force showed good results in white spots, It became inferior in durability.

  The optical laminated body to which the polarizing film with a pressure-sensitive adhesive or the set of polarizing films of the present invention is applied can be suitably used for a liquid crystal display device because it has few white spots and is excellent in durability even when it is enlarged. For example, it is suitable for an optical laminate such as a TN liquid crystal cell. Moreover, when this optical laminated body is used for an STN liquid crystal cell, the occurrence of color unevenness can be suppressed.

It is a cross-sectional schematic diagram which shows the layer structural example of the polarizing film with an adhesive which concerns on this invention. It is a cross-sectional schematic diagram which shows the example of the polarizing film with an adhesive which laminated | stacked the brightness improvement film. It is a cross-sectional schematic diagram which shows the layer structural example of the optical laminated body which concerns on this invention. It is a cross-sectional schematic diagram which shows the example of the optical laminated body which laminated | stacked the brightness enhancement film on the 1st polarizing film side, and provided the surface treatment layer in the outer surface of the 2nd polarizing film.

Explanation of symbols

10: First polarizing film with adhesive,
11 …… First adhesive layer,
12 ... Amorphous cyclic polyolefin resin film,
13 ... Polarizer,
14 …… Protective film,
15 …… First polarizing film,
17 …… Brightness enhancement film,
20 …… Second polarizing film with adhesive,
21 …… Second adhesive layer,
22, 24 …… Protective film,
23 …… Polarizer,
25 …… Second polarizing film,
27 …… Surface treatment layer,
30 …… Optical laminate,
35: Glass cell for liquid crystal display.

Claims (28)

  A polarizing film having a structure of an amorphous cyclic polyolefin resin film / polarizer / protective film, and an adhesive layer provided on the outer side of the amorphous cyclic polyolefin resin film, A polarizing film with an adhesive, wherein the fraction is 75 to 95% by weight.   The polarizing film with an adhesive according to claim 1, wherein the adhesive layer is formed from an adhesive in which a crosslinking agent is blended with an acrylic resin.   The pressure-sensitive adhesive contains an acrylic resin containing a structural unit derived from a (meth) acrylic acid compound having a polar functional group as a main component and derived from a (meth) acrylic acid alkyl ester. Polarizing film with adhesive.   The polarizing film with an adhesive according to claim 3, wherein the polar functional group is selected from the group consisting of a free carboxyl group, a hydroxyl group, an amino group, and an epoxy ring.   The pressure-sensitive adhesive-attached polarizing film according to claim 3 or 4, wherein the pressure-sensitive adhesive contains an acrylic resin having a structural unit derived from (meth) acrylic acid alkyl ester as a main component and a weight average molecular weight of 1,000,000 to 2,000,000.   The polarizing film with an adhesive according to any one of claims 2 to 5, wherein the crosslinking agent contains an isocyanate compound.   The pressure-sensitive adhesive film according to any one of claims 2 to 6, wherein the pressure-sensitive adhesive further contains a silane compound.   The pressure-sensitive adhesive layer according to claim 1, wherein the pressure-sensitive adhesive layer has a thickness of 20 μm or less.   The polarizing film with an adhesive according to claim 1, wherein a brightness enhancement film is laminated on the outside of the protective film.   An optical laminate, wherein the polarizing film with the pressure-sensitive adhesive according to any one of claims 1 to 9 is adhered to one side of a glass cell for liquid crystal display on the pressure-sensitive adhesive layer side.   A first polarizing film having a structure of an amorphous cyclic polyolefin resin film / polarizer / protective film is provided on one surface of a glass cell for liquid crystal display via a first adhesive layer. The second polarizing film is pasted on the other side of the glass cell with a acetylcellulose-based protective film pasted on both sides of the polarizer via a second adhesive layer. The first pressure-sensitive adhesive layer has a gel fraction of 75 to 95% by weight, and the second pressure-sensitive adhesive layer has a gel fraction of 30 to 70% by weight.   The optical laminate according to claim 11, wherein the second polarizing film has a surface treatment layer on a surface opposite to the second adhesive layer.   The optical laminate according to claim 11 or 12, wherein a brightness enhancement film is laminated on the outer side of the protective film of the first polarizing film.   The optical laminate according to any one of claims 11 to 13, wherein the first adhesive layer and the second adhesive layer are each formed from an adhesive in which a crosslinking agent is blended in an acrylic resin.   The pressure-sensitive adhesive constituting the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is derived from a (meth) acrylic acid-based compound having a structural unit derived from (meth) acrylic acid alkyl ester as a main component and having a polar functional group. The optical laminate according to claim 14, comprising a first acrylic resin comprising a structural unit and having a weight average molecular weight of 1,000,000 to 2,000,000.   In addition to the first acrylic resin, the pressure-sensitive adhesive constituting the second pressure-sensitive adhesive layer is mainly composed of a structural unit derived from (meth) acrylic acid alkyl ester, and has a weight average molecular weight of 50,000 to 500,000. The optical laminated body of Claim 15 containing an acrylic resin.   The optical layered product according to any one of claims 14 to 16, wherein the pressure-sensitive adhesive constituting the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer further contains a silane compound.   A first polarizing film having a structure of an amorphous cyclic polyolefin resin film / polarizer / protective film is provided on one surface of a glass cell for liquid crystal display via a first adhesive layer. The second polarizing film composed of an amorphous cyclic polyolefin resin film / polarizer / protective film is attached to the other side of the glass cell on the other side of the glass cell. An optical layered body characterized in that the first adhesive layer and the second adhesive layer have a gel fraction of 75 to 95% by weight.   The optical laminated body according to claim 18, wherein the second polarizing film has a surface treatment layer on a surface opposite to the second adhesive layer.   The optical laminate according to claim 18 or 19, wherein a brightness enhancement film is laminated on the outer side of the protective film of the first polarizing film.   The optical laminate according to any one of claims 18 to 20, wherein each of the first adhesive layer and the second adhesive layer is formed from an adhesive in which a crosslinking agent is blended with an acrylic resin.   The pressure-sensitive adhesive constituting the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is derived from a (meth) acrylic acid-based compound having a structural unit derived from (meth) acrylic acid alkyl ester as a main component and having a polar functional group. The optical laminated body according to claim 21, comprising a first acrylic resin containing a structural unit and having a weight average molecular weight of 1,000,000 to 2,000,000.   The optical layered product according to claim 21 or 22, wherein the pressure-sensitive adhesive constituting the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer further contains a silane compound. A first polarizing film having a configuration of an amorphous cyclic polyolefin-based resin film / polarizer / protective film, and a first adhesive layer provided outside the amorphous cyclic polyolefin-based resin film A polarizing film with a pressure-sensitive adhesive, and a second pressure-sensitive adhesive having a second polarizing film in which an acetylcellulose-based protective film is bonded to both sides of the polarizer and a second pressure-sensitive adhesive layer provided on one side A polarizing film,
The first adhesive layer has a gel fraction of 75 to 95% by weight,
The second adhesive layer has a gel fraction of 30 to 70% by weight. A polarizing film set for a liquid crystal display device.   The set of polarizing films according to claim 24, wherein the second polarizing film with a pressure-sensitive adhesive has a surface treatment layer on a surface opposite to the second pressure-sensitive adhesive layer.   When the adhesive layer is provided on the amorphous cyclic polyolefin resin film side of the polarizing film having the structure of amorphous cyclic polyolefin resin film / polarizer / protective film, the adhesive layer has a gel fraction of 75 to 95. A method for producing a polarizing film with a pressure-sensitive adhesive, wherein the polarizing film is prepared so as to be wt% and provided on the surface of the amorphous cyclic polyolefin-based resin film of the polarizing film.   27. The method according to claim 26, wherein a corona discharge treatment is applied to the surface of the amorphous cyclic polyolefin resin film prior to providing an adhesive layer on the surface of the amorphous cyclic polyolefin resin film.   The method according to claim 27, wherein the corona discharge treatment is performed at an output of 200 to 1,000 W.

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