KR100777877B1 - Peeling force adjusting method, pressure-sensitive adhesive layer for optical member and process for producing the same, and optical member with pressure-sensitive adhesive - Google Patents

Abstract

The present invention is to provide a method for adjusting the peel force of a silicone release liner easily without using a silicone component such as a heavy release agent. Moreover, it is providing the adhesive layer for optical members which is excellent in durability, and has an appropriate peeling force, and its manufacturing method. Moreover, it is for providing the optical member with pressure sensitive adhesive which has the said adhesive layer, and the image display apparatus using the same. The peel force adjusting method of the silicone release liner of the present invention includes a step of providing a layer of the pressure-sensitive adhesive composition containing a base polymer and a peroxide on the peeling treatment surface of the silicone release liner, and a step of thermally decomposing part or all of the peroxide. do.

Description

PEELING FORCE ADJUSTING METHOD, PRESSURE-SENSITIVE ADHESIVE LAYER FOR OPTICAL MEMBER AND PROCESS FOR PRODUCING THE SAME, AND OPTICAL MEMBER WITH PRESSURE-SENSITIVE ADHESIVE}

Figure 1 shows the relationship between the peroxide decomposition amount and the peeling force in Examples and the like.

The present invention provides a method for adjusting the peeling force of a silicone release liner, a pressure-sensitive adhesive layer for an optical member with a silicone release liner in which a pressure-sensitive adhesive layer is laminated on a peeling treatment surface of a silicone release liner, a method for producing the same, and an optical member with a pressure-sensitive adhesive with a silicone release liner. It is about. Moreover, it is related with image display apparatuses, such as a liquid crystal display device, an organic electroluminescence display, and a PDP using the adhesive layer for optical members. As said optical member, a polarizing plate, a retardation plate, an optical compensation film, a brightness improving film, what these laminated | stacked, etc. are mentioned.

The optical member used for a liquid crystal display device etc., for example, a polarizing plate, a retardation plate, etc. are adhered to a liquid crystal cell using an adhesive. Usually, the optical member with an adhesive in which the adhesive layer was laminated | stacked on the optical member is used. Since the material used for an optical member has a big expansion and contraction under heating conditions or humidification conditions, lifting and peeling accompanying with it are likely to occur after attachment. Therefore, the adhesive for optical members requires the durability which can respond also under heating conditions or humidification conditions.

In addition, these adhesive-attached optical members have shown the smoothness integrated with the peeling liner which performed the normal silicone peeling process. As the release liner of the optical member with pressure-sensitive adhesive, a release liner obtained by precisely coating silicone on a PET film is used because of excellent transparency, heat resistance, smoothness, and low appearance defects.

Although this silicone peeling liner is peeled off at the time when it becomes unnecessary, when the peeling force of the silicone peeling liner at the time of peeling removal is too large, it is difficult to peel off when peeling off a peeling liner, On the other hand, when it is too small, There arises a problem that the release liner is lifted or peeled off during the optical member manufacturing process, and an appropriate peel force is required.

As a method of adjusting the said appropriate peeling force, the method of changing the usage-amount of a silicone component is proposed, for example (for example, Unexamined-Japanese-Patent No. 1994-298875 and Unexamined-Japanese-Patent No. 2000-199199). However, when the peeling force is adjusted to the silicone component using, for example, a heavy release agent or the like, there is a possibility that the heavy release agent is transferred to the adhesive surface to lower the adhesive property. Moreover, when the silicone peeling liner was wound by the disk, the heavy release agent was transferred to the back surface, and the problem that the defect generate | occur | produced when peeling a peeling liner was discovered.

Then, an object of this invention is to provide the peeling force adjustment method of a silicone peeling liner easily, without using a silicone component, such as a heavy release agent. Moreover, an object of this invention is to provide the adhesive layer for optical members with a silicone peeling liner which is excellent in durability and has a suitable peeling force, and its manufacturing method. Moreover, it aims at providing the optical member with adhesive with a silicone peeling liner which has the said adhesive layer, and the image display apparatus using the same.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, it discovered that the said objective can be achieved by using the method shown below as a peeling force adjustment method of a silicone peeling liner, and came to complete this invention.

That is, the peeling force adjustment method of the silicone peeling liner of this invention is a process of providing the layer of the adhesive composition containing a base polymer and a peroxide on the peeling process surface of a silicone peeling liner, and heat-decomposing part or all of the said peroxides. It includes a process.

Moreover, the manufacturing method of the adhesive layer with a silicone release liner of this invention is a manufacturing method of the adhesive layer which includes the process of providing the layer of the adhesive composition containing a base polymer and a peroxide in the peeling process surface of a silicone release liner, It includes the process of adjusting the peeling force of a peeling liner.

According to the peeling force adjustment method of the silicone release liner of this invention, as shown in the result of an Example, the process of providing the layer of the adhesive composition containing a base polymer and a peroxide, and the process of heat-decomposing part or all of the said peroxides By using the peeling force adjustment method of the silicone peeling liner containing these, the peeling force of a silicone peeling liner can be adjusted easily. Although the details of the reason why the peeling force of the silicone release liner can be easily adjusted by the adjustment method are not clear, the hydrogen active reaction in the silicon molecule occurs due to the radical active species generated by the thermal decomposition of the peroxide in the pressure-sensitive adhesive composition. As a result, it is assumed that the silicon surface is denatured.

In the peeling force adjustment method of the said silicone peeling liner, it is preferable to heat-decompose 1-20 micromol of said peroxides with respect to 1g of said adhesive compositions. By adjusting the amount of peroxide, an appropriate peeling force can be expressed and peeling force can be adjusted.

Moreover, the manufacturing method of the adhesive layer with a silicone release liner of this invention is a manufacturing method of the adhesive layer which includes the process of providing the layer of the adhesive composition containing a base polymer and a peroxide in the peeling process surface of a silicone release liner, It includes the process of adjusting the peeling force of a peeling liner. By using this manufacturing method, the adhesive layer for optical members which is excellent in durability and has an appropriate peeling force can be obtained.

In the manufacturing method of the said adhesive layer, it is preferable that the said adhesive composition contains as a base polymer the (meth) acrylic-type polymer which has 80 weight part or more of (meth) acrylic-acid alkylesters in 100 weight part of monomer components. By using this adhesive composition, the adhesive layer for optical members which is excellent in durability and has an appropriate peeling force can be obtained.

Moreover, in the manufacturing method of the said adhesive layer, 0.01-1 weight part of silane coupling agents can be contained in 100 weight part of adhesive compositions. By using this adhesive composition, the adhesive layer for optical members which is excellent in durability and has an appropriate peeling force can be obtained.

On the other hand, the manufacturing method of the adhesive sheet with a silicone peeling liner of this invention contains the process of providing the layer of the adhesive composition containing a base polymer and a peroxide on the peeling process surface of a silicone peeling liner, The adhesive sheet with a silicone peeling liner In the production method of, characterized in that the peeling force of the silicon release liner is adjusted to be in the range of 0.1 to 0.4 N / 50 mm by the step of thermally decomposing part or all of the peroxide. By using this manufacturing method, the adhesive sheet with a silicone peeling liner which is excellent in durability and has an appropriate peeling force can be obtained.

On the other hand, the adhesive layer for optical members of this invention is manufactured by the said method. Since the adhesive layer of this invention exhibits the above effects, the adhesive sheet for optical members which is excellent in durability and has an appropriate peeling force can be obtained by using the adhesive layer of this invention. For this reason, it becomes especially useful as a re-peelable adhesive layer.

Moreover, the adhesive sheet for optical members of this invention forms the adhesive layer manufactured by the said method on a peeling liner. According to the adhesive sheet for optical members of this invention, since it is provided with the adhesive layer which shows the above effects, it becomes the adhesive sheet for optical members which is excellent in durability and has an appropriate peeling force.

Moreover, the optical member with pressure sensitive adhesive of this invention is formed by forming the said adhesive layer for optical members on one side or both surfaces of an optical member. According to the optical member with a pressure-sensitive adhesive of the present invention, since the pressure-sensitive adhesive layer exhibiting the above-described effects can be provided, the optical member with pressure-sensitive adhesive is excellent in durability and has an appropriate peeling force.

In addition, the image display device of the present invention is a liquid crystal display device using the pressure-sensitive optical member, an organic EL display device, a PDP, and the like, even if stored in a high temperature and high humidity state, high durability without peeling or foaming occurs, resulting in an optical member Even when the film is peeled off and the image display device is reused, no increase in the adhesive force is seen, and it has a function of easily peeling off without adversely affecting the device.

The peeling force adjustment method of the silicone peeling liner of this invention provides the process of providing the layer of the adhesive composition containing a base polymer and a peroxide on the peeling process surface of a silicone peeling liner, and the process of heat-decomposing part or all of the said peroxide. It is to include.

Although the hot melt coating which does not use the dispersion solvent of an adhesive composition can be used at the process of providing the layer of the adhesive composition of this invention, in order to improve coating precision, it is preferable to use a dispersion solvent.

The said dispersion solvent is not specifically limited, For example, organic solvents, such as toluene, ethyl acetate, alcohols, ketones, water, etc. can be used suitably. Moreover, coating using the solvent used for superposition | polymerization of a polymer is also possible, Moreover, a solvent can also be added and used suitably. These solvents may be used alone, or may be used by mixing two or more kinds.

As shown in Adhesion Handbook (Second Edition), P174, Adhesive Tape Industrial Edition, Oct. 12, 1995, a silicone release liner includes a condensation-reactive silicone release agent (e.g., a polydie having hydroxyl groups at both ends as a base polymer). Methylsiloxane, polymethylhydrodienesiloxane as a crosslinking agent, tin system as a catalyst is generally used, and addition reaction type silicone release agent (e.g., polydie having hydroxyl groups at both ends as a base polymer) Although a part of the methyl group of methylsiloxane is substituted by a vinyl group, polymethylhydrodienesiloxane as a crosslinking agent, and a platinum-based catalyst are generally used as a catalyst) are used, but it does not specifically limit in this invention, Any peeling agent A peeling liner using may also be used.

The peroxide of the present invention can be suitably used as long as it generates radically active species by heating and reacts with the silicone of the release liner. However, in view of workability and stability, a peroxide having a half-life temperature of 80 ° C to 160 ° C for 1 minute is used. It is preferable to use, and it is more preferable to use the peroxide which is 90 degreeC-140 degreeC. If the half-life temperature is too low for 1 minute, the reaction may proceed at the time of storage before application drying, and the viscosity may become high, and coating may be impossible. On the other hand, if the half-life temperature is too high, the temperature at the time of crosslinking reaction becomes high, thereby causing side reaction. This occurs, and a large amount of unreacted peroxide remains, which may cause crosslinking over time, which is undesirable. On the other hand, the half-life of a peroxide is an index which shows the decomposition rate of a peroxide, and means the time until the residual amount of a peroxide becomes half. The decomposition temperature for obtaining the half life at any time and the half life time at any temperature are described in the manufacturer's catalog and the like. For example, Nippon Yushi Co., Ltd. Organic Peroxide Catalog 9th Edition (May 2003) and the like.

Examples of peroxides that can be used in the present invention include, for example, di (2-ethylhexyl) peroxydicarbonate (1 minute half-life temperature: 90.6 ° C.), di (4-t-butylcyclohexyl) peroxydicarbonate (1 minute half-life temperature). : 92.1 ° C.), di-sec-butyl peroxydicarbonate (1 minute half life temperature: 92.4 ° C.), t-butyl peroxy neodecanoate (1 minute half life temperature: 103.5 ° C.), t-hexyl peroxy pivalate (1 minute half life temperature: 109.1 ° C.), t-butylperoxy pivalate (1 minute half life temperature: 110.3 ° C.), dilauroyl peroxide (1 minute half life temperature: 116.4 ° C.), di-n-octanoyl peroxide (1 minute half-life temperature: 117.4 ° C), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (1 minute half-life temperature: 124.3 ° C), di (4-methylbenzoyl) peroxide ( 1 minute half-life temperature: 128.2 ° C), dibenzoyl peroxide (1 minute half-life temperature: 130.0 ° C), t-butylperoxyisobutyrate (1 minute and a half Exchanger temperature: 136.1 ℃), 1,1- di (t--hexylperoxy) cyclohexane (one minute half life temperature: 149.2 ℃, and the like). Among them, because of its excellent crosslinking reaction efficiency, di (4-t-butylcyclohexyl) peroxydicarbonate (1 minute half-life temperature: 92.1 ° C), dilauroyl peroxide (1 minute half-life temperature: 116.4 ° C), dibenzoyl Peroxide (1 minute half life temperature: 130.0 degreeC) etc. are used preferably. These peroxides may be used alone, or may be used by mixing two or more kinds.

The adhesive composition in this invention is apply | coated to the peeling liner which performed the peeling process, and is dried, and becomes a layer of an adhesive composition. Moreover, the layer of the adhesive composition formed on the other base material can also be transferred to a peeling liner.

In the peeling force adjustment method of the present invention, in addition to adjusting the amount of peroxide, decomposition treatment temperature and decomposition treatment time are important.

In the present invention, the amount of decomposition of the peroxide is preferably 1 to 20 mol, more preferably 2 to 16 mol, and even more preferably 2 to 12 mol, with respect to 1 g of the pressure-sensitive adhesive composition. When the amount of decomposition of the peroxide is less than 1 µmol, the peeling force tends to be too small. On the other hand, when the amount of peroxide is more than 20 µmol, the peeling force tends to be too large.

The peroxide is used in an amount of 0.02 to 2 parts by weight based on 100 parts by weight of the pressure-sensitive adhesive composition, but it is more preferable to use 0.05 to 1 part by weight. When the amount is less than 0.02 parts by weight, the peeling force of the separator tends to be too small. On the other hand, when the amount is larger than 2 parts by weight, the peeling force tends to be too large, and a large amount of peroxide remains in the pressure-sensitive adhesive layer. Therefore, there exists a possibility that the adhesive characteristic may change.

There is no particular problem with respect to the decomposition treatment temperature and the decomposition treatment time of the peroxide, if it can be controlled so that the decomposition amount of the peroxide is 1 µmol to 20 µmol, preferably 2 µmol to 16 µmol, more preferably 2 µmol to 12 µmol per 1 g of the pressure-sensitive adhesive composition, At temperatures above 170 ° C, side reactions may occur. As the decomposition treatment temperature, the temperature at drying may be used as it is, or the decomposition treatment may be performed after drying. The treatment time is set in consideration of productivity and workability, but is usually about 0.2 to 20 minutes, preferably about 0.5 to 10 minutes.

The pressure-sensitive adhesive composition used in the present invention is not particularly limited as long as it has adhesiveness corresponding to the above-mentioned one, but a pressure-sensitive adhesive composition having a (meth) acrylic polymer as a base polymer is preferable.

As the (meth) acrylic acid alkyl ester used as the monomer component of the base polymer, an ester with an alcohol having 12 or less carbon atoms is used. Especially the (meth) acrylic-type monomer which has a C4-C12 alkyl group is preferable.

As said (meth) acrylic-type monomer, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, iso, for example Butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n -Nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, etc. are mentioned. These acrylic monomers may be used independently, and may mix and use 2 or more types.

In addition, the (meth) acrylic-type polymer in this invention means an acryl-type polymer and / or a methacryl-type polymer, and (meth) acrylate means an acrylate and / or a methacrylate.

As said (meth) acrylic-type polymer, the (meth) acrylic-type polymer which has 80 weight part or more of (meth) acrylic-acid alkylester in 100 weight part of monomer components is mentioned as a especially preferable thing.

It is preferable that the ratio of the (meth) acrylic-acid alkylester in the said (meth) acrylic-type polymer is 80 weight part or more (for example, about 80-99.8 weight part) in 100 weight part of monomer components, and 85 weight part or more (for example, 85-99.5) Part by weight) is more preferred. If it is less than 80 weight part, stress relaxation property will be insufficient and it is unpreferable.

Moreover, in this invention, functional group containing monomer containing functional groups, such as a hydroxyl group, can be used. The kind of such functional group can be selected suitably.

As a specific example of the said functional group containing monomer, (meth) acrylic acid, itaconic acid, maleic acid, crotonic acid, maleic anhydride, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl Carboxyl group-containing monomers such as phthalic acid or anhydrides thereof, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, Amide group containing monomers, such as N-butoxymethyl (meth) acrylamide, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, Hydroxyl group-containing monomers such as 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and polyethylene glycol mono (meth) acrylate , (Meth) acrylic acid dies Amino group-containing monomers such as methylaminoethyl and t-butylaminoethyl (meth) acrylate, glycidyl group-containing monomers such as glycidyl (meth) acrylate, (meth) acrylonitrile, and N- (meth) acryloyl Pauline, N-vinyl-2-pyrrolidone, etc. are mentioned.

Although the said functional group containing monomer may be used independently and may be combined, it is preferable that it is 0.01-20 weight part in 100 weight part of monomer components of a (meth) acrylic-type polymer, and it is more preferable that it is 0.05-10 weight part. When the content of the functional group-containing monomer is less than 0.01 part by weight, crosslinking may be insufficient, resulting in poor durability, which is not preferable. On the other hand, when content of a functional group containing monomer exceeds 20 weight part, since the adhesive force to a liquid crystal cell etc. tends to become too large, it is unpreferable.

The weight average molecular weight of the (meth) acrylic polymer used for this invention is 100,000 or more and 5 million or less, Preferably it is 200,000 or more and 4 million or less, More preferably, it is 300,000 or more and 3 million or less. When the weight average molecular weight is smaller than 100,000, the cohesive force of the pressure-sensitive adhesive composition tends to be small, thereby causing the adhesive to remain. On the other hand, when the weight average molecular weight exceeds 5 million, the fluidity of the polymer decreases and the wettability to the polarizing plate becomes insufficient, so that the air tends to remain between the adhesive composition layers such as the release liner and the optical member. have. The weight average molecular weight in this invention says what was obtained by measuring by GPC (gel permeation chromatography).

Moreover, it is preferable that the glass transition temperature (Tg) of the said (meth) acrylic-type polymer is 0 degrees C or less (usually 1100 degrees C or more), Preferably it is -10 degrees C or less. When the glass transition temperature is higher than 0 ° C., the polymer is difficult to flow and the wettability to the polarizing plate becomes insufficient, which tends to cause air to remain between the polarizing plate and the pressure-sensitive adhesive composition layer of the surface protective film. In addition, Tg of a (meth) acrylic-type polymer can be adjusted in the said range by suitably changing the monomer component and composition ratio to be used. In the present invention, the glass transition temperature (Tg) refers to one obtained by measuring by a measuring method using a dynamic viscoelastic device.

The polymerization method of the (meth) acrylic polymer used in the present invention is not particularly limited, and is appropriately polymerized by known methods such as solution polymerization, emulsion polymerization, block polymerization, suspension polymerization, and the like. In addition, the polymer obtained may be any of a random polymer and a block polymer. For example, when using solution polymerization, 0.01-0.2 weight part of polymerization initiators, such as azobisisobutyronitrile, are mix | blended with respect to 100 weight part of monomers, and it uses the polymerization solvent, such as ethyl acetate, at 50-70 degreeC under nitrogen stream. By making it react for 8 to 30 hours, a predetermined (meth) acrylic-type polymer can be obtained.

Moreover, in this invention, a peroxide can also be used as a polymerization initiator at the time of superposition | polymerization, such as a (meth) acrylic-type polymer. In such a case, it may not remain at the time of a polymerization reaction, and may remain in the layer of the said adhesive composition after that, However, the peeling force of a peeling liner can also be adjusted using this remaining peroxide. At this time, the remaining amount of unreacted peroxide can be quantified, and a peroxide can be added as needed to make a predetermined peroxide amount.

As a silane coupling agent in this invention, what is conventionally known can be used without a restriction | limiting in particular. For example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2- (3,4 epoxycyclohexyl) ethyl Epoxy-group-containing silane coupling agents such as trimethoxysilane, 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-triethoxysilyl Amino group-containing silane coupling agents such as -N- (1,3-dimethylbutylidene) propylamine, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, etc. Isocyanate group containing silane coupling agents, such as a meth) acryl group containing silane coupling agent and 3-iso cyanate propyl triethoxysilane, etc. are mentioned.

In the present invention, the silane coupling agent is blended 0.01 to 1 parts by weight, preferably 0.02 to 0.6 parts by weight based on 100 parts by weight of solids of the acrylic polymer. When the compounding quantity increases, the adhesive force to a liquid crystal cell etc. may increase, and re-peelability may fall, and when too small, durability may fall.

The adhesive composition of this invention becomes what is excellent in heat resistance more by crosslinking a (meth) acrylic-type polymer suitably. As a crosslinking agent used for this invention, an isocyanate compound, an epoxy compound, a melamine type resin, an aziridine derivative, a metal chelate compound, etc. are used. Among them, isocyanate compounds and epoxy compounds are particularly preferably used in view of obtaining appropriate cohesion. Especially, hydroxyl group is introduce | transduced into a polymer by copolymerizing hydroxyl group containing monomers, such as 2-hydroxyethyl acrylate at the time of manufacture of a polymer, and a polyisocyanate compound is used as a crosslinking agent with respect to such a polymer. It is desirable to. These compounds may be used alone or in combination.

As an isocyanate compound, Lower aliphatic polyisocyanates, such as butylene diisocyanate and hexamethylene diisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, for example Alicyclic isocyanates such as anate and isophorone diisocyanate, 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate Aromatic isocyanates such as cyanate, trimethylolpropane / tolylenediisocyanate trimer adduct (trade name Colonate L, manufactured by Nippon Polyurethane Co., Ltd.), trimethylolpropane / hexamethylenediiso Cyanate trimer adduct (brand name colonate HL, product of Nippon Polyurethanes Co., Ltd.), the hexamethylene diisocyanate And isocyanate adducts such as isocyanurate bodies (trade name Collonate HX, manufactured by Nippon Polyurethane Co., Ltd.), and diisocyanate adducts to polyols. These compounds may be used alone or in combination.

Examples of the epoxy compound include N, N, N ', N'-tetraglycidyl-m-xylenediamine (trade name TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and 1,3-bis (N, N-die Glycidylaminomethyl) cyclohexane (trade name TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.), and the like. These compounds may be used alone or in combination.

Hexamethylol melamine etc. are mentioned as melamine type resin. Examples of the aziridine derivatives include trade names HDU (manufactured by Sogo Pharmaceutical Co., Ltd.), trade name TAZM (manufactured by Sogo Pharmaceutical Co., Ltd.), trade name TAZO (manufactured by Sogo Pharmaceutical Co., Ltd.), and the like as commercially available products. These compounds may be used alone or in combination.

As a metal chelate compound, aluminum, iron, tin, titanium, nickel, etc., as a metal component, acetylene, methyl acetoacetate, ethyl lactate, etc. are mentioned as a chelate component. These compounds may be used alone or in combination.

Although content of the crosslinking agent used for this invention is about 0.01-5 weight part normally with respect to 100 weight part of (meth) acrylic-type polymers, it is preferable to adjust the crosslinking agent amount so that the gel powder after crosslinking by a crosslinking agent may be 45-95 weight%. And it is more preferable to adjust the crosslinking agent amount so that it may become 50 to 85 weight%. When the gel content is lower than 45% by weight, defects such as foaming occur in the heating test, and the cohesive force of the pressure-sensitive adhesive composition becomes small, which tends to cause adhesive residue. On the other hand, when gel content is higher than 95 weight%, the cohesion force of an adhesive composition becomes large and there exists a tendency for adhesiveness to be inferior.

In the present invention, the gel powder of the pressure-sensitive adhesive composition is a degree of crosslinking and represents the proportion of the portion crosslinked in the pressure-sensitive adhesive layer.

The measuring method of the said gel powder is shown below. About 0.1 g of the pressure-sensitive adhesive layer immediately after crosslinking treatment was taken and weighed to obtain the weight part W ₁ (g) of the pressure-sensitive adhesive layer. Subsequently, the pressure-sensitive adhesive layer was wrapped with a microporous tetrafluoroethylene membrane (when the film weight after wrapping was W ₂ (g)), immersed in about 50 ml of acetic acid at about 25 ° C. for 2 days, and then the soluble component was extracted and removed. . It was then taken out from the pressure-sensitive adhesive layer of ethyl acetate, and measured the weight W ₃ (g) after 1 hours and dried at 110 ℃. From these measured values, the gel fraction (% by weight) of the pressure-sensitive adhesive layer was obtained according to the following formula. Moreover, the gel fraction after storing for one week at room temperature after coating was measured.

Gel fraction (% by weight) = (W ₃ -W ₂ / W ₁ ) × 100.

The adhesive composition of this invention makes the above-mentioned (meth) acrylic-type polymer a base polymer.

In the present invention, the pressure-sensitive adhesive layer as an optional component, in addition to the above components, in addition to phenol resin, terpene-phenol resin, terpene resin, xylene resin, rosin, hydrogenated rosin, various tackifiers, such as calcium carbonate, carbon black, inorganic fillers, Powders such as lubricants, antioxidants, colorants, pigments, surfactants, plasticizers, antifoams, light stabilizers, thixotropic agents, UV absorbers, low molecular weight polymers, surface lubricants, leveling agents, antioxidants, polymerization inhibitors, heat stabilizers, and moisture Stabilizers such as coastal tablets, metal powder, particulates, thin powders and the like can be appropriately used. These arbitrary components may be used individually by 1 type, and may use 2 or more types.

2 micrometers-500 micrometers are preferable, and, as for the thickness of the adhesive layer used for this invention, 5 micrometers-100 micrometers are more preferable. When smaller than 2 micrometers, the adhesive force with respect to an optical member becomes inadequate, and when it exceeds 500 micrometers, adhesive force becomes saturated, it is not economical, and it becomes difficult to peel off because an adhesive may be pushed out or a cohesive failure may be carried out.

The pressure-sensitive adhesive layer of the present invention is formed by forming a pressure-sensitive adhesive layer containing such a pressure-sensitive adhesive composition on a peeled silicone release liner. In that case, although the formation of an adhesive layer is generally made to volatilize a solvent after application | coating of an adhesive composition solution, it is also possible to form by transferring the adhesive layer obtained by volatilizing a solvent from an adhesive composition solution, etc. to a peeling process base material. The pressure-sensitive adhesive composition may also be applied by forming a pressure-sensitive adhesive composition by a roll coater such as a reverse coater or gravure coater, a curtain coater, a lip coater, a die coater, a roll brush, a spray coating, or an air knife coating method. For example, curing may be carried out for the purpose of adjusting the component transition of the pressure-sensitive adhesive layer after the coating or adjusting the crosslinking reaction. In addition, when apply | coating an adhesive composition on a peeling process silicone peeling liner, you may newly add 1 or more types of solvents other than a polymerization solvent in the said composition so that it may apply | coat uniformly on a peeling process base material. As a peeling liner which performed the peeling process, the silicone peeling liner etc. which gave the silicone film peeling process to PET film, etc. are mentioned, for example.

The adhesive sheets of the present invention are made of a porous material such as plastic film, paper or nonwoven fabric such as polyester film, using a silicone release liner formed such that the thickness of the pressure-sensitive adhesive layer is usually 2 to 500 μm, preferably 5 to 100 μm. It is formed on one side or both sides of various support bodies which consist of etc., and it is set as the form of a sheet form, a tape form, etc.

It is preferable that the support body which comprises adhesive sheets is a resin film which has flexibility, having heat resistance and solvent resistance. Since the support has flexibility, the pressure-sensitive adhesive composition can be applied by a roll coater such as a reverse coater or a gravure coater, a curtain coater, a lip coater, a die coater, a roll brush, a spray coating, an air knife coating method, or the like. It can be wound up.

The resin for forming the support film, which is a support, is not particularly limited as long as it can be formed in a sheet form or a film form. Examples thereof include polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, and ethylene propylene. Polyolefin films such as copolymers, ethylene 1-butene copolymers, ethylene vinyl acetate copolymers, ethylene ethyl acrylate copolymers, ethylene vinyl alcohol copolymers, polyethylene terephthalates, polyethylene naphthalates, and polybutylene terephthalates Polyester films such as polyester film, polyacrylate film, polystyrene film, nylon 6, nylon 6,6, polyamide film such as partially aromatic polyamide, polyvinyl chloride film, polyvinylidene chloride film, polycarbonate film, polyfluoro Fluorine-containing resins such as ethylene, polyimide, nylon, cellulose and the like The.

On the other hand, in order to improve the adhesiveness between an adhesive layer and a support film, you may perform a corona treatment etc. to the surface of a support film. In addition, a backing process can also be performed to a support film.

The thickness of the said film is 5-200 micrometers normally, Preferably it is about 10-100 micrometers.

The manufacturing method of the adhesive layer for optical members of this invention includes the process of apply | coating the said adhesive composition on the peeling process silicone release liner, drying, and carrying out the thermal decomposition process of the said peroxide. The process is as described above.

The optical member of this invention forms the adhesive layer formed on the single side | surface or both surfaces of optical members, such as a polarizing plate, with the adhesive layer formed by the said manufacturing method.

When an adhesive layer is exposed on a surface, it will be suitably protected by the sheet etc. which carried out peeling process until it provided to practical use.

As an optical member, what is used for formation of image display apparatuses, such as a liquid crystal display device, is used, The kind in particular is not restrict | limited. For example, a polarizing plate is mentioned as an optical member. It is generally used that the polarizing plate has a transparent protective film on one side or both sides of the polarizer.

A polarizer is not specifically limited, Various things can be used. As a polarizer, it is made to adsorb | suck dichroic substances, such as iodine and a dichroic dye, to hydrophilic polymer films, such as a polyvinyl alcohol-type film, a partially foamed polyvinyl alcohol-type film, and an ethylene-vinyl acetate copolymerization system partial saponification film, for example. Polyene oriented films, such as extending | stretching, the dehydration process of polyvinyl alcohol, and the dehydrochlorination process of polyvinyl chloride, etc. are mentioned. Among these, the polarizer which consists of dichroic substances, such as a polyvinyl alcohol-type film and iodine, is suitable. Although the thickness in particular of these polarizers is not restrict | limited, Usually, it is about 5-80 micrometers.

The polarizer which uniaxially stretched the polyvinyl alcohol-type film by iodine can be produced by dyeing polyvinyl alcohol by immersing it in the aqueous solution of iodine, and extending | stretching 3 to 7 times the original length, for example. If necessary, it may be immersed in an aqueous solution such as potassium iodide, which may contain boric acid, zinc sulfate, zinc chloride, or the like. In addition, if necessary, the polyvinyl alcohol-based film may be immersed in water and washed before dyeing. By washing the polyvinyl alcohol-based film with water, the contamination of the surface of the polyvinyl alcohol-based film and the antiblocking agent can be washed, and the polyvinyl alcohol-based film is swelled to prevent irregularities such as staining. Stretching may be carried out after dyeing with iodine, may be performed while dyeing, or may be dyed with iodine after stretching. It can extend | stretch in aqueous solution, such as a boric acid and potassium iodide, or in a water bath.

As a material which forms the transparent protective film provided on one side or both sides of the said polarizer, what is excellent in transparency, mechanical strength, thermal stability, moisture shielding property, isotropy, etc. is preferable. For example, polyester polymers, such as polyethylene terephthalate and polyethylene naphthalate, cellulose polymers, such as diacetyl cellulose and triacetyl cellulose, acrylic polymers, such as polymethylmethacrylate, a polystyrene, an acrylonitrile styrene copolymer Styrene-type polymers, such as (AS resin), a polycarbonate polymer, etc. are mentioned. In addition, polyethylene, polypropylene, polyolefin having a cyclo- or norbornene structure, polyolefin-based polymer such as ethylene-propylene copolymer, vinyl chloride-based polymer, amide-based polymer such as nylon or aromatic polyamide, imide-based polymer, sulfone-based Polymer, polyether sulfone polymer, polyether ether ketone polymer, polyphenylene sulfide polymer, vinyl alcohol polymer, vinylidene chloride polymer, vinyl butyral polymer, allylate polymer, polyoxymethylene polymer , An epoxy polymer, or a blend of the above polymers may also be mentioned as examples of the polymer forming the transparent protective film. The transparent protective film can also be formed as a cured layer of a thermosetting or ultraviolet curing resin such as acrylic, urethane, acrylic urethane, epoxy, silicone or the like.

Further, the polymer film described in Japanese Patent Laid-Open No. 2001-343529 (WO01 / 37007), for example, a thermoplastic resin having a substituted and / or unsubstituted imide group in the (A) side chain, and (B) a substituted and / or in the side chain The resin composition containing the thermoplastic resin which has unsubstituted phenyl and a nitrile group is mentioned. As a specific example, the film of the resin composition containing the alternating copolymer which consists of isobutylene and N-methyl maleimide, and an acrylonitrile styrene copolymer is mentioned. The film can use the film which consists of mixed extrusion products of a resin composition, etc.

Although the thickness of a protective film can be suitably determined, it is generally about 1-500 micrometers in terms of workability, thinness, etc., such as strength and handleability. 1-300 micrometers is especially preferable, and 5-200 micrometers is more preferable.

Moreover, it is preferable that a protective film is as colorless as possible. Therefore, the phase difference in the film thickness direction represented by Rth = [(nx + ny) / 2-nz] · d (where nx and ny are the main refractive indexes in the film plane, nz is the refractive index in the film thickness direction, and d is the film thickness). The protective film whose value is -90 nm-+75 nm is used preferably. By using the thing whose phase difference value Rth of such a thickness direction is -90 nm-+75 nm, coloring (optical coloring) of the polarizing plate resulting from a protective film can be almost eliminated. The thickness direction retardation value Rth is more preferably -80 nm to +60 nm, particularly -70 nm to +45 nm.

As a protective film, cellulose polymers, such as triacetyl cellulose, are preferable at the surface, such as polarization characteristic and durability. In particular, triacetyl cellulose film is suitable. In addition, when providing a protective film on both sides of a polarizer, the protective film which consists of the same polymer material may be used in the front and back, and the protective film which consists of different polymer materials etc. may be used. The polarizer and the protective film are usually in close contact with each other through an aqueous adhesive. As an aqueous adhesive, an isocyanate adhesive, a polyvinyl alcohol adhesive, a gelatin adhesive, a vinyl latex type, an aqueous polyurethane, an aqueous polyester, etc. can be illustrated.

The surface which does not adhere | attach the polarizer of the said transparent protective film may be the thing which performed the process for the purpose of a hard-coat layer, an anti-reflective process, sticking prevention, and diffused or anti-glare.

The hard coating treatment is carried out for the purpose of preventing scratches on the surface of the polarizing plate, for example, by adding a cured film having excellent hardness and sliding properties by suitable UV curable resins such as acrylic and silicone to the surface of the transparent protective film. Can be formed. The antireflection treatment is performed for the purpose of preventing reflection of external light on the surface of the polarizing plate, and can be achieved by forming an antireflection film or the like according to the prior art. Incidentally, the anti-sticking treatment is performed for the purpose of preventing the adhesion with the adjacent layer.

The anti-glare treatment is performed for the purpose of preventing external light from being reflected from the surface of the polarizing plate and impairing the visibility of the polarizing plate transmitted light. For example, a roughening method or a compounding method of transparent fine particles by a sand blasting method or an embossing processing method. It can form by providing a fine uneven | corrugated structure to the surface of a transparent protective film by a suitable method, such as these. Examples of the fine particles to be included in the formation of the surface fine uneven structure include inorganic, which may be conductive, for example made of silica, alumina, titania, zirconia, tin oxide, indium oxide, cadmium oxide, antimony oxide, or the like having an average particle diameter of 0.5 to 50 µm. Transparent fine particles such as organic fine particles composed of fine particles, crosslinked or uncrosslinked polymers, and the like are used. When forming surface fine uneven structure, the usage-amount of microparticles | fine-particles is about 2-50 weight part generally with respect to 100 weight part of transparent resin which forms surface fine uneven structure, and 5-25 weight part is preferable. The anti-glare layer may also serve as a diffusion layer (visual magnification function or the like) for diffusing the polarizing plate transmitted light to enlarge the time and the like.

In addition, the anti-reflection layer, the anti-seizure layer, the diffusion layer or the anti-glare layer may be provided on the transparent protective film itself, but may be provided as a separate optical layer as a separate thing from the transparent protective film.

Moreover, as an optical member of this invention, formation of liquid crystal display devices, such as a reflecting plate, a semi-transmissive plate, a retardation plate (including wavelength plates, such as 1/2 or a quarter), a visual compensation film, a brightness enhancement film, etc. The thing which becomes an optical layer which can be used for is mentioned. These can be used alone as the optical member of the present invention and can be laminated on the polarizing plate for practical use, and can be used in one or two or more layers.

Particularly, a reflective polarizer or transflective polarizer in which a reflection plate or a semi-transmissive reflector is further laminated on the polarizing plate, an elliptically polarizing plate or circular polarizer in which a phase difference plate is further laminated on the polarizer, or an optical compensation film laminated on the polarizer The polarizing plate which laminated | stacked the brightness improving film further in a viewing angle polarizing plate or a polarizing plate is preferable.

The reflective polarizer is provided with a reflective layer on the polarizer to form a liquid crystal display device of the type which reflects and displays incident light from the viewing side (display side). This is advantageous in that the display device can be thinner. Formation of a reflective polarizing plate can be performed by a suitable method, such as the method of laying a reflective layer which consists of metal etc. on one surface of a polarizing plate through a transparent protective layer etc. as needed.

As a specific example of a reflective polarizing plate, the thing which formed the reflective layer by laying the foil and vapor deposition film which consist of reflective metals, such as aluminum, on one surface of the transparent protective film which carried out the mat process as needed. Moreover, what contains microparticles | fine-particles in the said transparent protective film to make surface fine concavo-convex structure, and has a reflective layer of a fine concavo-convex structure on it, etc. are mentioned. The reflective layer of the fine concavo-convex structure has the advantage of preventing the unevenness of light and shade by preventing incident light by diffusing diffused light by diffuse reflection. In addition, the fine particle-containing transparent protective film also has an advantage of being able to diffuse when incident light and its reflected light transmit therethrough, thereby further suppressing light and shade unevenness. The surface of the transparent protective film is formed of a reflective layer having a fine concavo-convex structure reflecting the metal on the surface of the transparent protective layer by a suitable method such as a deposition method or a plating method such as vacuum deposition, ion plating or sputtering. It can be carried out by the method of laying directly on the.

The reflecting plate can also be used as a reflecting sheet or the like formed by providing a reflecting layer on a suitable film according to the transparent film instead of the method of directly applying to the transparent protective film of the polarizing plate. In addition, since the reflective layer is usually made of a metal, the use form in which the reflective surface is covered with a transparent protective film, a polarizing plate, or the like prevents the reduction of the reflectance by oxidation, and furthermore, the long-term sustained side of the initial reflectance or the protective layer. It is preferable in terms of avoiding additional laying.

The semi-transmissive polarizing plate can be obtained by forming a semi-transmissive reflecting layer such as a half mirror that transmits while reflecting light from the reflecting layer. The semi-transmissive polarizer is usually provided on the back of the liquid crystal cell, and when the liquid crystal display device or the like is used in a relatively bright atmosphere, it reflects the incident light from the viewing side (display side) to display an image. In a relatively dark atmosphere, the transflective polarizer is used. A liquid crystal display of the type for displaying an image may be formed using a built-in light source such as a backlight built in the back of the. That is, the transflective polarizing plate can save energy of using a light source such as a backlight in a bright atmosphere, and is useful for forming a type of liquid crystal display or the like that can be used using a built-in light source even in a relatively dark atmosphere.

An elliptical polarizing plate or circular polarizing plate in which a retardation plate is further laminated on the polarizing plate will be described. A retardation plate or the like is used to change linearly polarized light into elliptical polarization or circularly polarized light, to change elliptical polarization or circularly polarized light into linearly polarized light, or to change the polarization direction of linearly polarized light. In particular, a so-called quarter wave plate (also referred to as λ / 4 plate) is used as a phase difference plate for converting linearly polarized light into circularly polarized light or for converting circularly polarized light into linearly polarized light. A half wave plate (also called a λ / 2 plate) is usually used when changing the polarization direction of linearly polarized light.

The elliptical polarizing plate is effectively used for black-and-white display without the coloring by compensating (preventing) coloration (blue or yellow) generated by the birefringence of the liquid crystal layer of the super twist nematic (STN) type liquid crystal display device. In addition, controlling the three-dimensional refractive index is preferable because it can compensate (prevent) the coloration generated when the screen of the liquid crystal display device is viewed in the oblique direction. The circular polarizing plate is effectively used, for example, when adjusting the color tone of an image of a reflection type liquid crystal display device in which an image becomes color display, and also has a function of antireflection.

As a retardation plate, the birefringent film formed by carrying out the uniaxial or biaxial stretching process of a polymeric material, the orientation film of a liquid crystal polymer, the thing which supported the orientation layer of a liquid crystal polymer with the film, etc. are mentioned. Although the thickness of the retardation plate is not particularly limited, it is generally about 20 to 150 µm.

Examples of the polymer material include polyvinyl alcohol, polyvinyl butyral, polymethylvinyl ether, polyhydroxyethyl acrylate, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, polycarbonate, polyallylate, polysulfone, Polyethylene terephthalate, polyethylene naphthalate, polyether sulfone, polyphenylene sulfide, polyphenylene oxide, polyallyl sulfone, polyvinyl alcohol, polyamide, polyimide, polyolefin, polyvinyl chloride, cellulose polymer, norbornene-based resin Or various copolymers of these binary or ternary systems, graft copolymers, blends, and the like. These high molecular materials become an orientation substance (stretched film) by extending | stretching etc.

As a liquid crystalline polymer, the conjugated linear atomic group (mesogen) which provides liquid crystal aligning property, the main chain type or side chain type | mold various things etc. which were introduce | transduced into the main chain or side chain of a polymer are mentioned, for example. As a specific example of a main-chain liquid crystalline polymer, the nematic oriented polyester-type liquid crystalline polymer, a discotic polymer, a cholesteric polymer, etc. of the structure which couple | bonded the mesogenic group in the spacer part which provides flexibility are mentioned. Specific examples of the branched liquid crystalline polymer include polysiloxane, polyacrylate, polymethacrylate, or polymalonate as a main chain skeleton, and a para-substituted ring having a nematic orientation imparting effect through a spacer portion composed of a conjugated atomic group as a side chain. The thing which has the mesogenic part which consists of a compound unit, etc. are mentioned. These liquid crystalline polymers develop a liquid crystalline polymer solution on an alignment treatment surface such as a rubbing treatment of a surface of a thin film such as polyimide or polyvinyl alcohol formed on a glass plate, or vapor deposition of silicon oxide in an oblique direction. It is carried out by heat treatment.

The retardation plate may have a suitable retardation according to the purpose of use, for example, for the purpose of compensating coloring or vision due to birefringence of various wavelength plates or liquid crystal layers, or by retarding two or more retardation plates. The optical characteristic of this may be controlled.

The elliptical polarizing plate and the reflective elliptic polarizing plate are obtained by laminating a polarizing plate or a reflective polarizing plate and a phase difference plate in a suitable combination. Such elliptical polarizing plates and the like can also be formed by sequentially stacking them separately in the manufacturing process of the liquid crystal display device so as to be a combination of the (reflective) polarizing plate and the retardation plate. It is excellent in the stability of quality, lamination | stacking workability, etc., and there exists an advantage which can improve manufacturing efficiency, such as a liquid crystal display device.

The visual compensation film is a film for widening the viewing angle so that an image can be seen relatively clearly even when the screen of the liquid crystal display device is viewed from a slightly inclined direction rather than perpendicular to the screen. As such a visual compensation retardation plate, it consists of what supported an alignment layer, such as a liquid crystal polymer, on alignment films, such as a retardation plate and a liquid crystal polymer, and a transparent base material, etc., for example. A conventional retardation plate is a polymer film having birefringence uniaxially stretched in the plane direction thereof, whereas a retardation plate used as a visual compensation film is a polymer film having birefringence uniaxially stretched in the plane direction, or the plane direction A biaxially stretched film such as a birefringent polymer or a diagonally oriented film, which is stretched uniaxially and controlled in the thickness direction also stretched in the thickness direction, is used. As a diagonal oriented film, the thing which carried out the extending | stretching process and / or shrinkage treatment of the polymer film, or the diagonal orientation of the liquid crystal polymer, etc. are mentioned, for example by adhering a heat shrink film to a polymer film, and the action of the shrinkage force by heating. The raw material polymer of the retardation plate is the same as the polymer described for the retardation plate, and is suitable for the purpose of preventing the coloring due to the change of the viewing angle based on the phase difference by the liquid crystal cell, or expanding the viewing angle of good visibility. Can be used.

In addition, an optical compensation retardation plate which supports an optically anisotropic layer composed of an alignment layer of a liquid crystal polymer, particularly an oblique alignment layer of a discotic liquid crystal polymer, in terms of achieving a wide viewing angle with good visibility can be preferably used. .

The polarizing plate which bonded the polarizing plate and the brightness enhancement film is usually installed on the back side of the liquid crystal cell and used. The luminance enhancing film reflects linear polarization of a predetermined polarization axis or circular polarization in a predetermined direction when natural light enters by a backlight such as a liquid crystal display device or reflection from the back, and exhibits a property of transmitting other light. The polarizing plate laminated with the polarizing plate receives light from a light source such as a backlight to obtain transmitted light in a predetermined polarization state, and light other than the predetermined polarization state is reflected without being transmitted. The light reflected from the surface of the brightness enhancing film is further inverted through a reflecting layer or the like provided behind the light and then reincident to the brightness enhancing film, and the part or all of the light is transmitted as light in a predetermined polarization state to transmit the brightness enhancing film. The luminance can be improved by increasing the amount of light and increasing the amount of light that can be used for liquid crystal display image display by supplying polarized light that is hardly absorbed by the polarizer. That is, in the case where light is incident on the backside of the liquid crystal cell by a backlight or the like without using the brightness enhancement film, most of the light having a polarization direction that does not coincide with the polarization axis of the polarizer is absorbed by the polarizer, thereby transmitting the polarizer. You will not. That is, although it depends also on the characteristic of the polarizer used, about 50% of light is absorbed by a polarizer, and the quantity of light which can be used for a liquid crystal image display etc. decreases by that amount, and an image becomes dark. The brightness enhancement film repeatedly reflects light having a polarization direction absorbed by the polarizer into the brightness enhancement film without being incident on the polarizer, and is further inverted through a reflective layer or the like installed behind the light and then re-injected into the brightness enhancement film. Since only the polarization direction in which the polarization direction of the light reflected and inverted between the two becomes the polarization direction through which the polarizer can pass, the luminance enhancement film is transmitted and supplied to the polarizer, so that light such as a backlight can be efficiently transferred to the image of the liquid crystal display device. We can use for indication and can brighten screen.

A diffuser plate may be provided between the brightness enhancing film and the reflective layer. The light in the polarization state reflected by the brightness enhancing film is directed toward the reflective layer or the like, and the diffuser plate provided uniformly diffuses the light passing therethrough and at the same time dissolves the polarization state into a non-polarization state. In other words, the diffusion plate returns the polarized light to the original natural light state. The light in this non-polarization state, that is, the natural light state, is reflected toward the reflection layer or the like through the reflection layer or the like, and passes through the diffuser plate again and is reincident to the brightness enhancement film. Thus, by providing a diffuser plate for returning the polarization to the original natural light state between the brightness enhancement film and the reflective layer, while maintaining the brightness of the display screen, at the same time to reduce the unevenness of the brightness of the display screen to provide a uniform and bright screen can do. By providing such a diffuser plate, it is considered that the number of times the first incident light was repeatedly increased, and the uniform incident light could be provided in conjunction with the diffuser function of the diffuser plate.

Examples of the brightness enhancement film include a film that transmits linearly polarized light of a predetermined polarization axis and reflects other light, such as a multilayer thin film of a dielectric or a multilayer laminate of thin film films having different refractive index anisotropy, and an alignment film of a cholesteric liquid crystal polymer. As the support of the alignment liquid crystal layer on the film substrate, suitable ones such as those exhibiting the characteristics of reflecting the circularly polarized light of either left or by-pass and transmitting other light can be used.

Therefore, in the luminance improvement film of the type which transmits the linearly polarized light of the said predetermined polarization axis, it can transmit efficiently while suppressing the absorption loss by a polarizing plate by making the transmitted light into a polarizing plate and making it incident. On the other hand, in the luminance-enhancing film of the type which transmits circularly polarized light like a cholesteric liquid crystal layer, although it may be made to enter a polarizer as it is, in view of suppressing absorption loss, the circularly polarized light is linearly polarized through a retardation plate to the polarizing plate. It is preferable to make it incident. In addition, circular polarization can be converted into linearly polarized light by using a quarter wave plate as the retardation plate.

A retardation plate functioning as a quarter wave plate in a wide wavelength range such as visible light region or the like is a retardation layer exhibiting retardation characteristics different from a retardation layer functioning as a quarter wave plate with respect to pale color light having a wavelength of 550 nm, for example 1/2. It can obtain by the method of superimposing the retardation layer which functions as a wave plate. Therefore, the retardation plate disposed between the polarizing plate and the brightness enhancement film may be composed of one or two or more retardation layers.

On the other hand, when the cholesteric liquid crystal layer has a layered structure in which two or three or more layers are superimposed with a combination of different reflection wavelengths, it is possible to obtain the reflection of circularly polarized light in a wide wavelength range such as a visible light region. The transmission circular polarization of a wide wavelength range can be obtained.

In addition, the polarizing plate may be formed by laminating a polarizing plate and two or three or more optical layers like the polarization splitting polarizing plate. Therefore, it may be a reflective elliptically polarizing plate, a semi-transmissive elliptically polarizing plate, etc. which combined the said reflective polarizing plate, a transflective polarizing plate, and a phase difference plate.

Although the optical member which laminated | stacked the said optical layer on the polarizing plate can also be formed by the method of separately laminating | stacking sequentially in the manufacturing process of a liquid crystal display device, etc., what laminated | stacked previously was made into the optical member is excellent in quality stability, an assembly work, etc. There is an advantage that the manufacturing process such as a liquid crystal display device can be improved. Suitable lamination means such as an adhesive layer can be used for lamination. At the time of adhering the above-mentioned polarizing plate and another optical layer, these optical axes can be made into an appropriate arrangement angle according to the phase difference characteristic made into the objective.

In addition, each layer, such as an optical member and an adhesive layer, of an adhesive optical member of the present invention is, for example, a salicylic acid ester compound, a benzophenol compound, a benzotriazole compound, a cyanoacrylate compound, a nickel complex salt compound, or the like. The thing which gave ultraviolet absorption ability by the system, such as a process with a ultraviolet absorber, etc. may be sufficient.

The adhesive optical member of this invention can be used suitably for formation of various image display apparatuses, such as a liquid crystal display device. Formation of a liquid crystal display device can be performed according to the prior art. That is, the liquid crystal display device is generally formed by appropriately assembling a component such as a liquid crystal cell, an adhesive optical member, and a lighting system as necessary to incorporate a driving circuit, but in the present invention, the optical according to the present invention is used. There is no restriction | limiting in particular except using a member, and it can follow conventionally. Also about a liquid crystal cell, arbitrary types, such as TN type, STN type, (pi) type, can be used, for example.

An appropriate liquid crystal display device such as a liquid crystal display device in which an adhesive optical member is disposed on one or both of the liquid crystal cells, or a backlight or reflector used in an illumination system can be formed. In this case, the optical member according to the present invention can be provided on one or both sides of the liquid crystal cell. In the case of providing the optical members on both sides, these may be the same or different. In forming the liquid crystal display device, for example, a diffuser plate, an anti-glare layer, an anti-reflection film, a protective plate, a prism array, a lens array sheet, a light diffuser plate, a backlight, or the like may be disposed at appropriate positions with one or two or more layers. Can be.

Next, an organic electroluminescent device (organic EL display device) will be described. In general, an organic EL display device forms a light emitting body (organic electroluminescent light emitting body) by sequentially stacking a transparent electrode, an organic light emitting layer, and a metal electrode on a transparent substrate. Here, the organic light emitting layer is a laminate of various organic thin films, for example, a hole injection layer made of a triphenylamine derivative or the like and a light emitting layer made of a fluorescent organic solid such as anthracene, or an electron made of such a light emitting layer and a perylene derivative. The structure which has various combinations, such as the laminated body of an injection layer or these laminated bodies of a hole injection layer, a light emitting layer, and an electron injection layer, is known.

In the organic EL display device, holes and electrons are injected into the organic light emitting layer by applying a voltage to the transparent electrode and the metal electrode, and energy generated by the recombination of these holes and electrons excites the fluorescent material, and the excited fluorescent material is based on When it returns to a state, it emits light on the principle of emitting light. The mechanism of intermediate recombination is the same as that of a general diode, and as can be expected from this, the current and the emission intensity exhibit strong nonlinearity accompanied by rectification with respect to the applied voltage.

In the organic EL display device, at least one electrode must be transparent in order to extract light emitted from the organic light emitting layer, and therefore, a transparent electrode formed of a transparent conductor such as indium tin oxide (ITO) is usually used as an anode. On the other hand, in order to facilitate electron injection and increase luminous efficiency, it is important to use a material having a small work function for the cathode, and metal electrodes such as Mg-Ag and Al-Li are usually used.

In the organic EL display device having such a configuration, the organic light emitting layer is formed of a very thin film having a thickness of about 10 nm. For this reason, the organic light emitting layer also transmits light almost completely like the transparent electrode. As a result, light incident on the surface of the transparent substrate during non-emission, and transmitted through the transparent electrode and the organic light emitting layer and reflected by the metal electrode again exits to the surface side of the transparent substrate, displays the organic EL display device when viewed from the outside. The surface looks like a mirror.

An organic EL display device comprising an organic electroluminescent light emitting body comprising a metal electrode on the back side of an organic light emitting layer while providing a transparent electrode on the front side of the organic light emitting layer that emits light by application of a voltage. A retardation plate can be provided between these transparent electrodes and a polarizing plate, providing a polarizing plate.

Since the retardation plate and the polarizing plate have a function of polarizing light incident from the outside and reflected from the metal electrode, the retardation plate and the polarizing plate have an effect of not allowing the mirror surface of the metal electrode to be visually recognized from the outside. Particularly, the mirror surface of the metal electrode can be completely shielded by adjusting the angle formed by the polarization direction between the polarizing plate and the retardation plate to π / 4 while configuring the retardation plate as a quarter wave plate.

That is, only the linearly polarized light component transmits external light incident on the organic EL display device by the polarizing plate. This linearly polarized light is generally elliptically polarized by the retardation plate. In particular, when the retardation plate is a quarter wave plate and the angle between the polarization direction of the polarizing plate and the retardation plate is? / 4, it is circularly polarized light.

This circularly polarized light penetrates the transparent substrate, the transparent electrode, and the organic thin film, is reflected by the metal electrode, and again passes through the organic thin film, the transparent electrode, and the transparent substrate, and is again linearly polarized on the retardation plate. And since this linearly polarized light is orthogonal to the polarization direction of a polarizing plate, it cannot pass through a polarizing plate. As a result, the mirror surface of a metal electrode can be shielded completely.

<Example>

Although an Example demonstrates this invention concretely below, this invention is not limited by these Examples. In addition, the evaluation item in the Example etc. was measured as follows. In addition, all% in each case is a basis of weight.

<Measurement of the weight average molecular weight of the acrylic polymer>

The weight average molecular weight of the produced polymer was measured by GPC (gel permeation chromatography).

Device: Tosoh Corporation, HLC-8120 GPC

column:

Sample column; Tosoh Corporation, G7000 H _XL + GMH _XL + GMH _XL

Flow rate: 0.8 ml / min

Injection volume: 100 μl

Column temperature: 40 ℃

Eluent: THF

Injection sample concentration: 0.1% by weight

Detector: Differential Refractometer

In addition, the weight average molecular weight was computed by polystyrene conversion.

<Measurement of peroxide decomposition amount>

The amount of peroxide decomposition after the pyrolysis treatment was measured by HPLC (high performance liquid chromatography).

About 0.2 g of each pressure-sensitive adhesive composition before and after the decomposition treatment was taken out, immersed in 10 ml of ethyl acetate, and vibration-extracted at 120 rpm at 25 ° C. for 3 hours with a vibrator, and then left standing at room temperature for 3 days. Subsequently, 10 ml of acetonitrile were added, and about 10 µl of the extract obtained by vibrating at 120 rpm for 30 minutes at 25 ° C. and filtered through a membrane filter (0.45 µm) was injected into HPLC to analyze the amount of peroxide before and after the decomposition treatment. The reduction was made into the amount of peroxide decomposition.

Device: Tosoh Corporation, HPL CCPM / UV8000

column:

Sample column; NUCLEOSIL 7C18 (4.6mmφ * 250mm) made in MACHEREY-NAGEL company

Flow rate: 1.0ml / min

Column pressure: 41 kg / cm ²

Column temperature: 40 ℃

Eluent: water / acetonitrile = 30/70

Injection volume: 10 μl

Injection sample concentration: 0.01% by weight

Detector: UV detector (230 nm)

<Measurement of peeling force of the peeling liner>

The peeling force of the peeling liner when the optical member with a peeling liner cut | disconnected to the produced width 50mm and the magnitude | size of 100 mm in length was peeled off by the universal tension tester at the peel rate of 300 mm / min (peel angle 180 degrees). . The measurement was performed in an environment of 23 ° C. × 50% RH. When the peeling force is less than 0.1 N / 50 mm, since peeling force is too small, the problem that a peeling liner floats in a manufacturing process, such as a punch, is easy to arise. On the other hand, when larger than 0.4 N / 50mm, since peeling force becomes large too much, the problem which becomes difficult to peel a peeling liner at the time of actual use easily occurs.

<Evaluation of Durability>

The produced optical member (12-inch size) was attached to an alkali free glass plate (Corning Corporation, trade name Corning 1737, 250 x 350 mm, thickness: 0.7 mm), and subjected to autoclave treatment at a pressure of 50 MPa and 0.5 MPa for 30 minutes. . Thereafter, 500 hours of storage at 60 ° C. × 90% RH was returned to room temperature to obtain a sample for evaluation. The adhesion state to the glass plate after this process was confirmed, and the following references | standards evaluated.

No lifting or peeling of the optical member occurred: ○

Lifting or peeling of the optical member occurs: ×

Example 1

95 parts by weight of butyl acrylate, 3.0 parts by weight of acrylic acid, 0.10 parts by weight of 2-hydroxyethyl acrylate, 0.050 parts by weight of 2,2-azobisisobutyronitrile and 200 parts by weight of ethyl acetate, a nitrogen inlet tube, and cooling The mixture was charged into a four-necked flask equipped with a tube, and sufficiently replaced with nitrogen, and then subjected to a polymerization reaction at 55 ° C. for 20 hours while stirring under a nitrogen stream to obtain a solution of a high molecular weight acrylic polymer A having a weight average molecular weight of 1.57 million.

0.15 part by weight of dibenzoyl peroxide (1 minute half-life: 130.0 ° C) based on 100 parts by weight of the solution (solid content) of the acrylic polymer A, 0.080 part by weight of 3-glycidoxy propyl trimethoxysilane as a silane coupling agent The pressure-sensitive adhesive composition was prepared by uniformly mixing 0.60 parts by weight of an isocyanate-based crosslinking agent (colonate L, manufactured by Nippon Polyurethane Co., Ltd.) comprising a tolylenediisocyanate adduct of trimethylolpropane as a crosslinking agent.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (additional reaction type silicone), 38μm thick) in which the pressure-sensitive adhesive composition was applied so that the adhesive layer had a dry thickness of 25μm, dried at 150 ° C. for 2 minutes, and peroxide. The decomposition treatment was performed and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel component of the pressure-sensitive adhesive layer was 69%, and the amount of decomposition of the peroxide was 7.56 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 2

In Example 1, the optical member with an adhesive was produced like Example 1 except having used 0.30 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel content of the pressure-sensitive adhesive layer was 82%, and the amount of decomposition of the peroxide was 11.74 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 3

In Example 1, a polyethylene terephthalate film (Mitsubishi Polyester company, MRN38 (condensation reaction silicone)) was used instead of the polyethylene terephthalate film (Mitsubishi Polyester company, MRF38 (addition reaction type silicone)). In the same manner as in Example 1, an optical member with an adhesive was produced. On the other hand, the gel content of the pressure-sensitive adhesive layer was 70%, and the amount of decomposition of the peroxide was 7.50 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 4

100 parts by weight of isooctyl acrylate, 1.0 part by weight of 2-hydroxybutyl acrylate, and 0.10 part by weight of 2,2-azobisisobutyronitrile and 200 parts by weight of ethyl acetate are equipped with a nitrogen inlet tube and a cooling tube. After being charged into a four-necked flask and sufficiently nitrogen-substituted, a polymerization reaction was carried out at 55 ° C. for 20 hours with stirring under a nitrogen stream to obtain a solution of a high molecular weight acrylic polymer B of 1.75 million by weight average molecular weight.

0.15 part by weight of dibenzoyl peroxide (1 minute half life: 130.0 ° C.), 0.10 part by weight of 3-glycidoxypropyltrimethoxysilane as a silane coupling agent, based on 100 parts by weight of the solution (solid content) of the acrylic polymer B; 0.10 weight part of isocyanate type crosslinking agents (colonate L, the Nippon Polyurethane company make) which consisted of the tolylene diisocyanate adduct of trimethylol propane as a crosslinking agent were mixed uniformly, and the adhesive composition was produced.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (additional reaction type silicone), 38μm thick) in which the pressure-sensitive adhesive composition was applied so that the adhesive layer had a dry thickness of 25μm, dried at 150 ° C. for 2 minutes, and peroxide. The decomposition treatment was performed and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 79%, and the amount of decomposition of the peroxide was 8.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 5

In Example 4, the optical member with an adhesive was produced like Example 4 except having used 0.30 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel content of the pressure-sensitive adhesive layer was 83%, and the amount of decomposition of the peroxide was 12.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 6

70 parts by weight of 2-ethylhexyl acrylate, 29 parts by weight of butyl acrylate, 1.0 part by weight of acrylic acid, and 0.050 parts by weight of 2,2-azobisisobutyronitrile and 200 parts by weight of ethyl acetate were introduced into a nitrogen inlet tube and a cooling tube. The mixture was charged into a four-necked flask and sufficiently nitrogen-substituted, followed by a polymerization reaction at 55 ° C. for 20 hours with stirring under a nitrogen stream to obtain a solution of a high molecular weight acrylic polymer C having a weight average molecular weight of 1.46 million.

0.15 part by weight of dibenzoyl peroxide (1 minute half-life: 130.0 ° C.), 0.10 part by weight of 3-glycidoxypropyltrimethoxysilane as the silane coupling agent, based on 100 parts by weight of the solution (solid content) of the acrylic polymer C, As the crosslinking agent, 0.60 parts by weight of an isocyanate-based crosslinking agent (colonate L, manufactured by Nippon Polyurethane Co., Ltd.) consisting of tolylenediisocyanate adduct of trimethylolpropane was uniformly mixed to prepare an adhesive composition.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (added reactive silicone), 38 μm thick) subjected to silicone peeling so that the adhesive layer had a dry thickness of 25 μm, dried at 150 ° C. for 2 minutes, and The peroxide decomposition treatment was carried out and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 61%, and the amount of decomposition of the peroxide was 9.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 7

In Example 6, the optical member with an adhesive was produced like Example 6 except having used 0.30 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 74%, and the decomposition amount of the peroxide was 13.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 8

70 parts by weight of 2-ethylhexyl acrylate, 30 parts by weight of butyl acrylate, 1.0 part by weight of acrylic acid, and 0.070 part by weight of 3-acryloxypropyltriethoxysilane. Reactive emulsifier Aqualon HS-10 (Daiichi) To 2.0 parts by weight of water added 2.0 parts by weight of Kogyo Pharmaceutical Co., Ltd. was added and emulsified by a homo mixer to obtain an emulsion. Next, the mixture was charged into a four-necked flask equipped with a nitrogen inlet tube and a cooling tube, and nitrogen-substituted for 1 hour. Then, 30 parts by weight of water and 0.10 part by weight of initiator VA-057 (manufactured by Wako Pure Chemical Industries, Ltd.) were added thereto. The emulsion was added dropwise over 4.5 hours while maintaining the reaction system at 59 ° C to carry out the polymerization reaction. After completion of the reaction, ammonia was added to adjust the pH to 8 to obtain a solution of an acrylic acrylic polymer D of the emulsion type.

0.15 parts by weight of dibenzoyl peroxide (1 minute half-life: 130.0 ° C.) and 0.10 part by weight of 3-glycidoxypropyltrimethoxysilane as a silane coupling agent based on 100 parts by weight of the solution (solid content) of the acrylic polymer D. To make a pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (added reactive silicone), 38 μm thick) subjected to silicone peeling so that the adhesive layer had a dry thickness of 25 μm, dried at 150 ° C. for 2 minutes, and The peroxide decomposition treatment was carried out and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 72%, and the amount of decomposition of the peroxide was 12.4 µmol based on 1 g of the pressure-sensitive adhesive composition.

Example 9

0.15 part by weight of a di (4-t-butylcyclohexyl) peroxydicarbonate (1 minute half-life temperature: 92.1 ° C.) with respect to 100 parts by weight of the solution (solid content) of the acrylic polymer A, 3-glyciene as a silane coupling agent 0.60 parts by weight of isocyanate-based crosslinking agent (colonate L, manufactured by Nippon Polyurethane Co., Ltd.) comprising 0.080 parts by weight of doxypropyl trimethoxysilane and a tolylenediisocyanate adduct of trimethylolpropane as a crosslinking agent. The mixture was mixed to prepare an adhesive composition.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (added reactive silicone), 38 μm thick) subjected to silicone peeling so that the adhesive layer had a dry thickness of 25 μm, dried at 150 ° C. for 2 minutes, and The peroxide decomposition treatment was carried out and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel content of the pressure-sensitive adhesive layer was 81%, and the amount of decomposition of the peroxide was 8.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Example 10

0.30 part by weight of 1,1-di (t-hexylperoxy) cyclohexane (1 minute half-life temperature: 149.2 ° C) with respect to 100 parts by weight of the solution (solid content) of the acrylic polymer A, 3-glycine as a silane coupling agent 0.60 parts by weight of isocyanate-based crosslinking agent (colonate L, manufactured by Nippon Polyurethane Co., Ltd.) comprising 0.075 parts by weight of doxypropyl trimethoxysilane and tolylenediisocyanate adduct of trimethylolpropane as a crosslinking agent. To prepare a pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate film (Mitsubishi Polyester Co., Ltd., MRF38 (added reactive silicone), 38 μm thick) subjected to silicone peeling so that the adhesive layer had a dry thickness of 25 μm, dried at 150 ° C. for 2 minutes, and The peroxide decomposition treatment was carried out and transferred to the polarizing film to obtain an optical member with a pressure-sensitive adhesive of the present invention. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 72%, and the amount of decomposition of the peroxide was 5.0 mol relative to 1 g of the pressure-sensitive adhesive composition.

Comparative Example 1

In Example 1, the optical member with an adhesive was produced like Example 1 except not having added dibenzoyl peroxide. In addition, the gel powder of the adhesive layer was 62%.

Comparative Example 2

In Example 1, the optical member with an adhesive was produced like Example 1 except having used 0.60 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel content of the pressure-sensitive adhesive layer was 88%, and the decomposition amount of the peroxide was 22.2 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Comparative Example 3

In Example 3, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 3 except that no dibenzoyl peroxide was added. In addition, the gel powder of the adhesive layer was 59%.

Comparative Example 4

In Example 4, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 4 except that no dibenzoyl peroxide was added. In addition, the gel powder of the adhesive layer was 75%.

Comparative Example 5

In Example 4, the optical member with an adhesive was produced like Example 4 except having used 0.60 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 79%, and the amount of decomposition of the peroxide was 24.0 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Comparative Example 6

In Example 5, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 5 except that no dibenzoyl peroxide was added. In addition, the gel powder of the adhesive layer was 60%.

Comparative Example 7

In Example 5, the optical member with an adhesive was produced like Example 5 except having used 0.60 weight part of dibenzoyl peroxide instead of 0.30 weight part of dibenzoyl peroxide. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 78%, and the amount of decomposition of the peroxide was 21.0 µmol based on 1 g of the pressure-sensitive adhesive composition.

Comparative Example 8

In Example 8, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 8 except that no dibenzoyl peroxide was added. In addition, the gel powder of the adhesive layer was 63%.

Comparative Example 9

In Example 8, the optical member with an adhesive was produced like Example 8 except having used 0.60 weight part of dibenzoyl peroxide instead of 0.15 weight part of dibenzoyl peroxide. On the other hand, the gel fraction of the pressure-sensitive adhesive layer was 78%, and the amount of decomposition of the peroxide was 23.1 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Comparative Example 10

In Example 2, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 2 except that the silane coupling agent was not added. On the other hand, the gel content of the pressure-sensitive adhesive layer was 82%, and the amount of decomposition of the peroxide was 11.74 µmol with respect to 1 g of the pressure-sensitive adhesive composition.

Comparative Example 11

In Example 8, an optical member with a pressure-sensitive adhesive was produced in the same manner as in Example 8 except that the silane coupling agent was not added. On the other hand, the gel content of the pressure-sensitive adhesive layer was 78%, and the amount of decomposition of the peroxide was 12.4 µmol based on 1 g of the pressure-sensitive adhesive composition.

Comparative Example 12

In Example 1, it carried out similarly to Example 8 except having used 0.30 weight part of 2,2'- azobisisobutyronitrile (the Wako Pure Chemical Co., azo initiator) instead of 0.15 weight part of dibenzoyl peroxides. The optical member with an adhesive was manufactured. In addition, the gel powder of the adhesive layer was 72%.

The above evaluation of the optical member with pressure sensitive adhesive manufactured according to the said method was performed. The results obtained are shown in Table 1.

In addition, in Table 1, a compound species (peroxide and azo-type compound) is as follows.

a) Peroxide P:

Dibenzoyl peroxide

b) peroxide Q:

Di (4-t-butylcyclohexyl) peroxydicarbonate

c) peroxide R:

1,1-di (t-hexylperoxy) cyclohexane

d) azo compound S:

2,2'-Azobisisobutyronitrile

From the results in Table 1 above, when the step of forming the pressure-sensitive adhesive layer on the silicon release liner includes the step of decomposing the peroxide on the release liner according to the manufacturing method of the present invention (Examples 1 to 10), the whole example The adhesive layer for an optical member which was excellent in durability, and the peeling force of a silicone peeling liner was easily adjusted to an appropriate peeling force, and the optical member with pressure sensitive adhesive using the same was obtained (refer FIG. 1).

On the other hand, when the step of decomposing the peroxide on the release liner is not included (Comparative Examples 1, 3 to 4, 6, 8, 12), the durability of the release liner is 0.1 N / It became smaller than 50 mm, and adhesive force was inadequate. In addition, when the amount of peroxide decomposition was more than 20 µmol (Comparative Examples 2, 5, 7, 9), the durability was excellent, but in both cases, the peeling force of the release liner was larger than 0.4 N / 50 mm, resulting in excessively large peeling force. On the other hand, when it did not contain a silane coupling agent (Comparative Examples 10-11), although it had a moderate peeling force, in all, it was a result which was bad in durability.

Therefore, it was confirmed by the manufacturing method of the adhesive layer of this invention that the adhesive layer for optical members which is excellent in durability and has a suitable peeling force, and the optical member with adhesive using the same are obtained.

According to this invention, the adhesive layer for optical members which is excellent in durability and has an appropriate peeling force can be manufactured, and can use this to provide an optical member with an adhesive, and an image display apparatus using the same.

Claims (10)

The first step of providing a layer of a pressure-sensitive adhesive composition containing a (meth) acrylic polymer as a base polymer and a peroxide on the peeling treatment surface of the silicone release liner, and part or all of the peroxides performed after the first step are thermally decomposed. The peeling force adjustment method of the silicone peeling liner containing the 2nd process of adjusting the peeling force of the said silicone peeling liner. The method of claim 1, 1 to 20 µmol of the peroxide is thermally decomposed with respect to 1 g of the pressure-sensitive adhesive composition. A method for producing a pressure-sensitive adhesive layer comprising a first step of providing a layer of a pressure-sensitive adhesive composition containing a (meth) acrylic polymer as a base polymer and a peroxide on a peeling treatment surface of a silicone release liner, wherein the step performed after the first step A method for producing a pressure-sensitive adhesive layer with a silicone release liner comprising a second step of thermally decomposing a part or all of the peroxide to adjust the peel force of the silicone release liner. The method of claim 3, wherein The said adhesive composition is a manufacturing method of the adhesive layer with a silicone peeling liner which contains as a base polymer the (meth) acrylic-type polymer which has 80 weight part or more of (meth) acrylic-acid alkylester in 100 weight part of monomer components. The method of claim 3, wherein The said adhesive composition contains 0.01-1 weight part of silane coupling agents in 100 weight part of adhesive compositions, The manufacturing method of the adhesive layer with a silicone peeling liner. In the manufacturing method of the adhesive sheet with a silicone peeling liner containing the 1st process of providing the layer of the adhesive composition containing a (meth) acrylic-type polymer and a peroxide as a base polymer on the peeling process surface of a silicone peeling liner, Of the pressure-sensitive adhesive sheet with a silicone release liner adjusted so that the peeling force of the silicone release liner is in a range of 0.1 to 0.4 N / 50 mm by a second step of thermally decomposing a part or all of the peroxides performed after the first step. Manufacturing method. The adhesive layer for optical members with a silicone peeling liner manufactured by the method of any one of Claims 3-5. The adhesive sheet for an optical member with a silicone peeling liner which has the adhesive layer for the optical member with a silicone peeling liner manufactured by the method of any one of Claims 3-5. The pressure-sensitive adhesive layer for an optical member with a silicon release liner according to claim 7 is formed on one or both surfaces of the optical member. delete

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