TWI648362B - Optical adhesive layer, adhesive sheet, optical member and touch panel - Google Patents

Abstract

The present invention provides an optical member capable of suppressing the occurrence of undulations, maintaining high adhesion reliability and transparency, and having excellent corrosion resistance, and an adhesive layer and an adhesive sheet capable of efficiently manufacturing such an optical member at low cost.

The optical adhesive layer of the present invention is characterized in that it contains a base polymer and a rust inhibitor, and the base polymer does not contain or substantially does not contain an acidic group-containing monomer as a constituent monomer component, at 85 ° C. The elastic modulus is 5.0 × 10 ⁴ Pa or more.

Description

Optical adhesive layer, adhesive sheet, optical member and touch panel

The invention relates to an optical adhesive layer, an adhesive sheet, an optical member and a touch panel.

In recent years, a display device such as a liquid crystal display (LCD) or an input device such as a touch panel has been widely used in various fields. In the manufacture of such display devices or input devices, an adhesive sheet is used for bonding optical members. For example, the bonding of optical members in various display devices such as a touch panel uses a transparent adhesive sheet.

In such display devices or input devices, there is a problem that metal wiring is corroded due to intrusion of moisture or acid gas, saline water, and corrosive components from the external environment into the interior. In recent years, with the increase in the size or narrowing of sensors, the number of copper wirings has increased. Copper is known to have excellent conductivity after silver and is useful as a wiring material, but it is easily oxidized and corroded. In general, in order to prevent oxidation and corrosion of a metal, a method of preventing moisture or corrosive components from being infiltrated by applying a moisture-proof protective layer to a metal wiring (Patent Document 1).

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2011-28594

However, the above-mentioned coating must be performed after the metal wiring is applied. In terms of an increase in the number of steps and time and effort, it becomes a major problem in terms of reduction in manufacturing yield and cost. In addition, when a moisture-proof protective layer is used, it may be necessary to ensure adhesion and resistance to foaming and peeling (it is difficult to cause foaming or peeling at the interface between the adhesive sheet and the adherend in a high-temperature environment), etc. Then, problems arise in terms of reliability and transparency.

In addition, for a laminated body having a structure in which a metal film is laminated on a support, if a pattern is applied to the metal film, a patterned portion (pattern forming portion) and a non-patterned portion (pattern opening portion) are generated. In the case where such a metal film pattern is applied, the laminated body may fluctuate in a high temperature environment due to a difference in linear expansion coefficient between a material constituting the support and a metal constituting the metal film. Furthermore, if the above-mentioned undulations occur, the problem of poor appearance tends to occur. This is because the step difference between the pattern forming portion and the pattern opening portion (hereinafter sometimes referred to as “pattern boundary”) becomes larger than necessary, and it becomes easy to recognize the pattern boundary.

Therefore, an object of the present invention is to provide a method capable of suppressing the occurrence of undulations in a high-temperature environment, and maintaining high adhesion and resistance to foaming and peeling. Characteristics), etc., optical components (especially optical components with adhesive sheets) that are excellent in corrosion resistance and metal wiring such as copper wiring, and can be manufactured efficiently and at low cost. Optical adhesive layer and sheet.

Therefore, the present inventors have made intensive studies in order to solve the above problems, and as a result, they have found that by using an appropriate base polymer constituting an adhesive layer and using a rust preventive agent, they can have adhesion reliability, transparency, and anticorrosive effects. Furthermore, if the elastic modulus of the adhesive composition at high temperature is controlled, generation of fluctuations in a high temperature environment can be suppressed, thereby completing the present invention.

In particular, it has been found that the present invention can achieve a synergistic effect with the anticorrosive effect by not containing or substantially not containing an acid group-containing monomer as a monomer component constituting the base polymer, and using a rust inhibitor.

That is, the present invention provides an optical adhesive layer, which is characterized by containing a base polymer and a rust inhibitor, and the base polymer does not contain or substantially does not contain an acid group-containing monomer as a constituent monomer component thereof, The elastic modulus at 85 ° C is 5.0 × 10 ⁴ Pa or more.

Furthermore, the present invention provides an optical adhesive layer characterized in that it contains an acrylic polymer (A) as a main component and a rust inhibitor, and the acrylic polymer (A) as a constituent monomer component does not contain or The carboxyl group-containing monomer is not substantially contained, and the elastic modulus at 85 ° C is 5.0 × 10 ⁴ Pa or more.

It is preferable that the said adhesive layer for optics contains 5 weight part or more with respect to the total amount (100 weight part) of monomer components which comprise the acrylic polymer (A).

It is preferable that the said optical adhesive layer is 5 weight part or more with respect to the total amount (100 weight part) of monomer components which comprise the acrylic polymer (A).

The rust preventive agent is preferably a benzotriazole-based compound.

The optical adhesive layer preferably has a haze (based on JIS K7136) of 1.0% or less.

The optical adhesive layer preferably has a total light transmittance (based on JIS K7361-1) of 90% or more.

Furthermore, this invention provides the adhesive sheet which has the said adhesive layer for optics.

The above-mentioned pressure-sensitive adhesive sheet preferably has a 180 ° peel adhesion force to the glass plate of 8 N / 20 mm or more.

The thickness of the adhesive sheet is preferably 12 to 350 μm.

Furthermore, the present invention provides an optical member having at least the above-mentioned adhesive sheet and a substrate, wherein the substrate is provided with metal wiring on at least one side, and the above-mentioned adhesive sheet is adhered to a surface of the substrate on a side having the metal wiring.

In the optical member, the metal wiring is preferably a copper wiring.

Furthermore, the present invention provides a touch panel, which has at least the above-mentioned adhesive sheet and a substrate, and the substrate is provided with metal wiring on at least one side, and the above-mentioned adhesive sheet is pasted on a surface of the substrate on the side having the metal wiring. .

In the touch panel, the metal wiring is preferably a copper wiring.

According to the optical adhesive layer of the present invention, adhesion reliability, transparency, and anticorrosive effects can be provided. Therefore, it is possible to obtain adhesion reliability and transparency such as high retention of adhesion and resistance to foaming and peeling, and metal wiring such as copper wiring. An optical member having excellent anticorrosive effect, and an adhesive layer and an adhesive sheet which can realize the production of such an optical member. In addition, since the anticorrosive ability is provided to the adhesive layer, the number of steps can be reduced without applying a protective layer, thereby reducing the cost and improving the yield.

In addition, according to the optical adhesive layer of the present invention, the occurrence of undulations in a high-temperature environment can be suppressed, and thus an optical member having a good appearance and an adhesive layer and an adhesive sheet capable of manufacturing such an optical member can be obtained.

1, 4, 5‧‧‧‧ optical components

2‧‧‧Touch Panel

3‧‧‧ metal wiring

6‧‧‧ laminated body

10, 10a, 10b, 10c

11‧‧‧ transparent conductive film

12, 12a, 12b ‧‧‧ transparent substrate

13‧‧‧ film sensor

14a, 14b ‧‧‧ polarizing plates

15‧‧‧hard coating

20‧‧‧Glass with step difference (step difference test piece)

21‧‧‧ glass plate

22‧‧‧step

61‧‧‧ support

62‧‧‧metal film

71a, 72a, 73a, 74a, 75a, 76a ‧‧‧ metal wiring (pattern wiring)

71b, 72b, 73b, 74b, 75b, 76b ‧‧‧ Metal wiring (pattern wiring)

81, 82, 83, 84, 85, 86‧‧‧ electrodes (transparent electrodes)

1 (A) to (C) are schematic diagrams showing specific examples of preferred aspects of the optical member of the present invention.

2 <A) ~ (E) are schematic diagrams showing specific examples of preferred aspects of the touch panel of the present invention.

Fig. 3 is a plan view of a stepped glass used in the evaluation of resistance to foaming and peeling.

FIG. 4 is a cross-sectional view (AA 'cross-sectional view) of the stepped glass.

FIG. 5 is a cross-sectional view (B-B 'cross-sectional view) of the stepped glass.

FIG. 6 is a schematic cross-sectional view showing an example of a laminated body including a support and a metal film where undulations occur.

FIG. 7 is a schematic plan view showing an example of a metal wiring pattern.

[1. Adhesive layer for optics]

As long as the optical adhesive layer of the present invention contains a base polymer and a rust inhibitor as main components, the base polymer does not contain or substantially does not contain an acid group-containing monomer as a constituent monomer component, at 85 ° C. The elastic modulus may be 5.0 × 10 ⁴ Pa or more, and other aspects are not particularly limited. Furthermore, the adhesive composition of this invention contains at least a base polymer and a rust inhibitor.

The optical adhesive layer of the present invention does not contain or substantially does not contain an acidic group-containing monomer as a monomer component constituting the base polymer, and further contains a rust inhibitor, thereby obtaining an effect synergistic with the anti-corrosion effect, and is excellent Its anti-corrosive effect.

The optical adhesive layer of the present invention may contain an acrylic polymer (A) and a rust inhibitor as main components, and the acrylic polymer (A) does not contain or substantially does not contain a carboxyl group-containing monomer as Constituting a monomer component, the elastic modulus at 85 ° C is 5.0 × 10 ⁴ Pa or more.

The composition (adhesive composition, precursor composition) forming the optical adhesive layer of the present invention may have any form, and examples thereof include latex type, solvent type, hot-melt type (hot-melt type), and active energy ray. Hardening type and so on. In addition, in this specification, an adhesive composition means the composition which forms an adhesive layer, and includes the composition which forms an adhesive.

The base polymer contained in the optical adhesive layer of the present invention is not particularly limited, and examples thereof include an acrylic polymer as a base polymer contained in the acrylic adhesive layer, and a rubber-based adhesive layer (natural Rubber-based adhesive layer or synthetic rubber-based adhesive layer, etc.) as a base polymer, rubber-based polymer, polysiloxane-based adhesive layer as a base polymer, polysiloxane-based polymer, polymer Polyester polymer as the base polymer contained in the ester-based adhesive layer, Urethane polymer as the base polymer contained in the urethane-based adhesive layer, and Polyamide adhesive Polyamide-based polymer contained in the adhesive layer as the base polymer, epoxy-based polymer contained in the epoxy-based adhesive layer as the base polymer, and vinyl alkyl ether-based adhesive layer contained Vinyl alkyl ether polymers as the base polymer, fluorine polymers as the base polymer contained in the fluorine-based adhesive layer, and the like. Among these, the base polymer is preferably an acrylic polymer in terms of transparency, weather resistance, adhesion reliability, and easy function design of the adhesive layer due to abundant monomer types. That is, the optical adhesive layer of the present invention is preferably an acrylic adhesive layer containing the following acrylic polymer (A) as a base polymer. The base polymer may be used alone or in combination of two or more.

The content of the base polymer in the optical adhesive layer of the present invention is not particularly limited, but is preferably 75% by weight or more (for example, 75 to 99.9% by weight), and more preferably 85% by weight or more (for example, 85 to 99.9% by weight). %).

The optical adhesive layer of the present invention does not contain or substantially does not contain an acidic group-containing monomer (for example, a carboxyl group-containing monomer, a sulfo group-containing monomer, a phosphate group-containing monomer, etc.). Therefore, excellent corrosion resistance of the metal wiring can be obtained. The content of the acidic group-containing monomer is preferably 0.05% by weight or less (for example, 0 to 0.05% by weight), and more preferably 0.01% by weight or less (for example, 0 to 0.01) relative to the optical adhesive layer of the present invention. (Weight%), and more preferably 0.001% by weight or less (for example, 0 to 0.001% by weight) can be said to be substantially free.

When the optical adhesive layer of the present invention is an acrylic adhesive layer, the optical adhesive layer of the present invention does not contain or substantially does not contain an acidic group-containing monomer such as a carboxyl group-containing monomer as a basis. The monomer component of the acrylic polymer contained in the polymer. When the acrylic polymer (A) is contained as a base polymer, the optical adhesive layer of the present invention preferably contains no or substantially no carboxyl-containing monomer as a constituent of the acrylic polymer (A). Monomer composition. Therefore, the optical adhesive layer of the present invention can obtain an excellent anticorrosive effect. The meaning of a carboxyl group-containing monomer, the meaning of "substantially not containing", and a monomer having an acidic group other than a carboxyl group are the same as those of the monomer component constituting the acrylic polymer (A). The content of the carboxyl group-containing monomer is preferably 0.05% by weight or less (for example, 0 to 0.05% by weight), and more preferably 0.01% by weight or less (for example, 0 to 0.01) based on the total amount of the optical adhesive layer of the present invention. % By weight), more preferably 0.001 weight The amount is less than or equal to (for example, 0 to 0.001% by weight).

The optical adhesive layer of the present invention is transparent or has transparency. Therefore, the optical adhesive layer of the present invention is excellent in visibility and appearance.

The haze (based on JIS K7136) of the optical adhesive layer of the present invention is not particularly limited, but is preferably 1.0% or less, and more preferably 0.8% or less. When the haze is 1.0% or less, it is preferable because excellent transparency or excellent appearance can be obtained. In addition, regarding the above-mentioned haze, for example, an adhesive layer (thickness: 100 μm) can be prepared, and it can be allowed to stand in a normal state (23 ° C, 50% RH (Relative Humidity, relative humidity)) for at least 24 hours, and then bonded to Use a haze meter (manufactured by Murakami Color Technology Research Institute Co., Ltd., trade name "HM-150") on a glass slide (for example, a total light transmittance of 91.8% and a haze of 0.4%) as a sample ").

The total light transmittance (based on JIS K7361-1) of the optical adhesive layer of the present invention in the visible light wavelength region is not particularly limited, but is preferably 85% or more, and more preferably 88% or more. If the total light transmittance is 85% or more, it is preferable to obtain excellent transparency or excellent appearance. In addition, regarding the above-mentioned total light transmittance, for example, an adhesive layer (thickness: 100 μm) can be prepared, and it can be left to stand for at least 24 hours in a normal state (23 ° C, 50% RH). The separator is peeled off, and the adhesive sheet is attached to a glass slide (for example, a total light transmittance of 91.8% and a haze of 0.4%), and the obtained sample is used as a sample using a haze meter (Murakami Color Technology) Manufactured by Research Institute Co., Ltd., trade name "HM-150").

The elastic modulus of the optical adhesive layer of the present invention at 85 ° C. is 5.0 × 10 ⁴ Pa or more, more preferably 7.0 × 10 ⁴ Pa or more, and even more preferably 9.0 × 10 ⁴ Pa or more. Since the elastic modulus of the optical adhesive layer of the present invention at 85 ° C. is 5.0 × 10 ⁴ Pa or more, the occurrence of fluctuations can be suppressed. Therefore, according to the optical adhesive layer of the present invention, an optical member or a touch panel with a good appearance can be obtained. This is because it is possible to suppress the occurrence of a so-called "visible pattern" (a phenomenon in which the step boundary of a pattern boundary becomes larger than necessary to easily recognize the pattern boundary, resulting in deterioration of appearance).

The above-mentioned measurement of the elastic modulus at 85 ° C was obtained in the following manner. After making the adhesive layer (thickness: about 2mm), punch it into 7.9 mm. A cylindrical pellet was prepared as a measurement sample. Fix the above measurement sample to The temperature dependence of the storage elastic modulus G 'was measured on a 7.9 mm parallel plate fixture using a dynamic viscoelasticity measuring device (manufactured by Rhcomctrics, ARES). That is, it refers to the storage elastic modulus (G ') at 85 ° C when measured in a shear mode, a temperature range: -70 ° C to 150 ° C, a temperature increase rate: 5 ° C / min, and a frequency: 1Hz.

Regarding the above undulations, a schematic cross-sectional view of an example of a laminated body including a support and a metal film (a laminated body having a metal film pattern on the support) where the undulations are generated is shown in FIG. 6. In FIG. 6, 6 is a laminated body, 61 is a support body, and 62 is a metal film (metal film pattern). In this way, the so-called "undulations" refer to fluctuations and fluctuations.

The method for producing the optical adhesive layer is not particularly limited. For example, it can manufacture by manufacturing the said adhesive composition, and irradiating an active energy ray, heat-drying, etc. as needed. Specific examples include a method for preparing the polymerizable monomer mixture or a part of the polymer by adding a rust preventive agent (for example, the following benzotriazole-based compound, etc.), an additive, and the like as necessary and mixing them, and the like. .

The optical adhesive layer of the present invention contains a rust inhibitor. Rust inhibitors include compounds that prevent rust or corrosion of metals. The rust inhibitor is not particularly limited, and examples thereof include amine compounds, benzotriazole-based compounds, and nitrites. Other examples include ammonium benzoate, ammonium phthalate, ammonium stearate, ammonium palmitate, ammonium oleate, ammonium carbonate, dicyclohexylamine benzoate, urea, and cyclohexamethylene tetrachloride. Amine, thiourea, phenyl carbamate, N-cyclohexylamino carbamate cyclohexylammonium (CHC) and the like. Furthermore, the rust inhibitor can be used alone or in combination of two or more.

Examples of the amine compound include a hydroxyl-containing amine compound such as 2-amino-2-methyl-1-propanol, monoethanolamine, monoisopropanolamine, diethylethanolamine, ammonia, or ammonia water; Cyclic amines such as morpholine; cyclic alkylamine compounds such as cyclohexylamine; linear alkylamines such as 3-methoxypropylamine. Examples of the nitrites include dicyclohexyl ammonium nitrite (DICHAN), diisopropyl ammonium nitrite (DIPAN), sodium nitrite, potassium nitrite, and calcium nitrite.

Among them, in terms of compatibility and transparency of the base polymer, and further, in the case where the base polymer is reacted after addition, it is difficult to suppress the reaction (crosslinking, polymerization, etc.) of the base polymer, as described above. The rust inhibitor is preferably a benzotriazole-based compound.

The content of the rust inhibitor is not particularly limited, but it is preferably 0.02 to 15 parts by weight based on 100 parts by weight of the base polymer. When the said content is 0.02 weight part or more, it is easy to obtain favorable corrosion resistance, and it is preferable. On the other hand, if the content is less than 15 parts by weight, it is easy to ensure transparency, and it is easy to ensure adhesion reliability such as resistance to foaming and peeling. Therefore, it is preferable.

In particular, in terms of obtaining the characteristics of reliability, transparency, and corrosion resistance with better balance and higher levels, it is preferable that the above-mentioned base polymer is an acrylic polymer (especially the following acrylic acid) Polymer (A)) and the rust preventive agent is a benzotriazole-based compound. That is, the optical adhesive layer of the present invention preferably contains at least an acrylic polymer as a base polymer (especially the acrylic polymer (A) described below) and a benzotriazole-based compound as a rust preventive. Acrylic adhesive layer.

[1-1. Benzotriazole-based compound]

The content of the benzotriazole-based compound is not particularly limited, and is preferably 0.02 to 3 parts by weight, and more preferably 0.02 to 2.5, with respect to the total amount (100 parts by weight) of the monomer components constituting the acrylic polymer (A). It is more preferably 0.02 to 2 parts by weight. That is, the optical adhesive layer of the present invention preferably contains 0.02 to 3 parts by weight of the benzotriazole-based compound with respect to 100 parts by weight of the acrylic polymer (A), and more preferably contains 0.02 to 2.5 parts by weight. It is preferably contained in an amount of 0.02 to 2 parts by weight. When the amount of the benzotriazole-based compound is too small, the value of the change rate T of the sheet resistivity may not be set to a specific value or less. Also, because of benzotriazole The amount of the compound is equal to or less than a certain level, so that adhesion reliability such as resistance to foaming and peeling can be surely ensured, and the increase in the haze of the adhesive layer or the adhesive sheet can be reliably prevented.

The benzotriazole-based compound is not particularly limited as long as it is a compound having a benzotriazole skeleton. From the viewpoint of obtaining a more excellent anticorrosive effect, it is preferable to have the following formula (1): The structure of the representation.

(Wherein R ¹ and R ^{2 are the} same or different in formula (1), R ¹ is a substituent on a benzene ring, and represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and carbon 6 to 14 aryl, amine, mono or di C _1-10 alkylamino, amine-C _1-6 alkyl, mono or di C _1-10 alkylamino-C _1-6 alkane Substituents such as amino, mercapto, alkoxycarbonyl having 1 to 6 carbon atoms, n is an integer of 0 to 4, and when n is 2 or more, n R ¹ may be the same or different, and R ² represents a hydrogen atom , Alkyl group with 1 to 12 carbons, alkoxy group with 1 to 12 carbons, aryl group with 6 to 14 carbons, amine group, mono- or di-C _1-10 alkylamino group, amine group -C _{1- (6} alkyl, mono or di C _1-10 alkylamino-C _1-6 alkyl, mercapto, alkoxycarbonyl with 1 to 12 carbon substituents)

From the viewpoint of obtaining a more excellent anticorrosive effect, R ^{1 is} preferably an alkyl group or alkoxycarbonyl group having 1 to 3 carbon atoms, and more preferably a methyl group or the like. In addition, n is preferably 0 or 1.

On the same viewpoint, as R ^2, preferably a hydrogen atom, a mono- or di-C _1-10 alkylamino -C _1-6 alkyl group, etc., more preferably a hydrogen atom, di-C _{1 ~ 8-alkyl} Amine C _1-4 alkyl and the like.

[1-2. Acrylic polymer (A)]

The optical adhesive layer of the present invention preferably contains an acrylic polymer (A) as a main component. Percent acrylic adhesive layer. The specific content of the acrylic polymer (A) is not particularly limited, and is preferably 75% by weight or more (for example, 75 to 99.9% by weight) with respect to the total amount (total weight, 100% by weight) of the optical adhesive layer of the present invention. ), More preferably 85% by weight or more (for example, 85 to 99.9% by weight).

The adhesive composition for forming an optical adhesive layer containing an acrylic polymer (A) as a main component is not particularly limited, and examples thereof include a composition containing an acrylic polymer (A) as an essential component; and A mixture of monomer components (sometimes referred to as a "monomer mixture") constituting the acrylic polymer (A) or a composition in which a part of the polymer is an essential component. Although not particularly limited, examples of the former include so-called solvent-based compositions, and examples of the latter include so-called active energy ray-curable compositions. Furthermore, the above-mentioned adhesive composition may further include other additives as necessary.

The above-mentioned "monomer mixture" includes a case where it is composed of a single monomer component and a case where it is composed of two or more monomer components. In addition, the "partial polymer" mentioned above refers to a composition in which one or two or more of the constituents of the monomer mixture are partially polymerized. Among them, the adhesive composition is preferably a composition containing a monomer mixture or a partial polymer as an essential component.

The acrylic polymer (A) is a polymer containing an acrylic monomer as an essential monomer unit (Monomeric unit, monomer constituent unit). In other words, the acrylic polymer (A) is a polymer including, as a constituent unit, a constituent unit derived from an acrylic monomer. That is, the acrylic polymer (A) is a polymer constituted (formed) with an acrylic monomer as an essential monomer component. In addition, in this specification, "(meth) acrylic acid" means any one or both of "acrylic acid" and "methacrylic acid", and the other is the same. The weight average molecular weight of the acrylic polymer (A) is not particularly limited, but is preferably 100,000 to 5,000,000.

The acrylic polymer (A) preferably contains an alkyl (meth) acrylate having a linear or branched alkyl group (hereinafter sometimes simply referred to as "alkyl (meth) acrylate") as required Of monomer units.

Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, and (methyl) Base) butyl acrylate (n-butyl (meth) acrylate), isobutyl (meth) acrylate, second butyl (meth) acrylate, third butyl (meth) acrylate, (meth) acrylic acid Amyl ester, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (formyl) (Isyl) isooctyl acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate Ester, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, (meth) Hexadecyl acrylate, Heptadecyl (meth) acrylate, Octadecyl (meth) acrylate, Isostearyl (meth) acrylate, Undecyl (meth) acrylate Eicosyl (meth) acrylate Etc. The alkyl group having 1 to 20 carbon atoms of (meth) acrylate and the like. Moreover, an alkyl (meth) acrylate can be used individually or in combination of 2 or more types.

Among them, in terms of obtaining strong adhesiveness and adjusting residual stress, the alkyl (meth) acrylate is preferably an alkyl (meth) acrylate having 1 to 18 carbon atoms, and more preferably Preferred are methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), and isostearyl acrylate (ISTA).

The content (ratio) of the aforementioned (meth) acrylic acid alkyl ester in all the monomer units of the acrylic polymer (A) (the total amount of the monomer components constituting the acrylic polymer (A)) is not particularly limited. In terms of adhesion reliability, especially adhesion reliability at low temperature, it is preferably 30 to 95 parts by weight relative to the total amount of monomer components (100 parts by weight) constituting the acrylic polymer (A). It is preferably 35 to 90 parts by weight, and more preferably 40 to 85 parts by weight.

The acrylic polymer (A) may include a copolymerizable monomer (copolymerizable monomer) in addition to the above-mentioned (meth) acrylic acid alkyl ester as a monomer unit. That is, acrylic The polymer (A) may include a copolymerizable monomer as a monomer component thereof. The copolymerizable monomer may be used alone or in combination of two or more kinds.

Preferred examples of the copolymerizable monomer include a hydroxyl group-containing monomer. When the acrylic polymer (A) contains a hydroxyl group-containing monomer as a monomer unit, it is easy to polymerize when the constituent monomer components are polymerized, and it is easy to obtain good cohesion. Therefore, it is easy to obtain strong adhesiveness, and also to increase the gel fraction, and it is easy to obtain excellent foaming and peeling resistance. Furthermore, it is easy to suppress whitening of the adhesive sheet generated in a high humidity environment.

The content (ratio) of the above-mentioned hydroxyl group-containing monomer with respect to the total amount (100 parts by weight) of the monomer components constituting the acrylic polymer (A) is not particularly limited. When the amount of the hydroxyl-containing monomer is fixed or more, the whitening of the adhesive sheet generated in a high humidity environment can be further suppressed, and transparency such as resistance to humidification and white turbidity can be ensured. The lower limit of the content of the hydroxyl-containing monomer is preferably 5 parts by weight or more, more preferably 7 parts by weight or more, and even more preferably 10 parts by weight or more. The upper limit of the content of the hydroxyl group-containing monomer is preferably 40 parts by weight or less, and more preferably 35 in terms of cohesion, adhesion, foaming and peel resistance, and ease of availability of adhesion. Part by weight or less, more preferably 30 parts by weight or less.

Furthermore, as said copolymerizable monomer, the nitrogen atom containing monomer is mentioned preferably. When the acrylic polymer (A) contains a nitrogen atom-containing monomer as a monomer unit, it is easy to obtain an appropriate cohesive force. Therefore, the 180-degree peeling adhesive force to the glass plate and the 180-degree peeling adhesive force to the acrylic plate are increased, and strong adhesion is easily obtained. Further, the gel fraction is increased, and excellent foam resistance is easily obtained. Peelability. Furthermore, it is easy to obtain appropriate flexibility in the adhesive layer, adjust the 300% tensile residual stress to a specific range, and easily obtain excellent stress relaxation and excellent step followability.

The content (ratio) of the aforementioned nitrogen atom-containing monomer with respect to the total amount (100 parts by weight) of the monomer components constituting the acrylic polymer (A) is not particularly limited, but it is preferably 5 parts by weight or more. In terms of cohesion, adhesion, and resistance to foaming and peeling, with respect to the total amount of monomer components (100 parts by weight) constituting the acrylic polymer (A), The lower limit of the content is more preferably 7 parts by weight or more, and still more preferably 10 parts by weight or more. In addition, the upper limit of the content of the above-mentioned nitrogen atom-containing monomer is preferably 40 in terms of that it is easier to obtain appropriate flexibility of the adhesive layer, and it is easier to obtain excellent stress relaxation and excellent step followability. It is 35 parts by weight or less, more preferably 30 parts by weight or less.

The acrylic polymer (A) can be obtained by polymerizing the monomer unit (monomer component) by a known or conventional polymerization method. Examples of the polymerization method of the acrylic polymer (A) include a solution polymerization method, an emulsion polymerization method, a block polymerization method, and a polymerization method using an active energy ray irradiation (active energy ray polymerization method). Among them, in terms of transparency, water resistance, and cost of the adhesive layer, a solution polymerization method, an active energy ray polymerization method, and an active energy ray polymerization method are more preferable.

Examples of the active energy ray irradiated during the above-mentioned active energy ray polymerization (photopolymerization) include ionizing radiation such as α-rays, β-rays, γ-rays, neutron beams, and electron beams; In addition, the irradiation energy, irradiation time, irradiation method, and the like of the active energy ray are not particularly limited, as long as the photopolymerization initiator can be activated to generate a reaction of a monomer component.

When polymerizing the acrylic polymer (A), various general solvents may be used. Examples of the solvent include esters such as ethyl acetate and n-butyl acetate; aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as n-hexane and n-heptane; and cyclohexane and methylcyclohexane. Isoalicyclic hydrocarbons; organic solvents such as ketones such as methyl ethyl ketone and methyl isobutyl ketone. The solvents may be used alone or in combination of two or more.

In the polymerization of the acrylic polymer (A), a polymerization initiator such as a thermal polymerization initiator or a photopolymerization initiator (photoinitiator) may be used depending on the type of the polymerization reaction. Moreover, a polymerization initiator can be used individually or in combination of 2 or more types.

The photopolymerization initiator is not particularly limited, and examples thereof include benzoin ether-based photopolymerization initiator, acetophenone-based photopolymerization initiator, α-keto alcohol-based photopolymerization initiator, and aromatic sulfonic acid.醯 Chlorine-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzoin fluorene-based photopolymerization initiator, benzophenone-based photopolymerization initiator, ketal Photopolymerization initiator, 9-oxysulfur Photopolymerization initiators. The photopolymerization initiator may be used alone or in combination of two or more.

Examples of the benzoin ether-based photopolymerization initiator include benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether, benzoin isobutyl ether, and 2,2-dimethoxy-1,2-diphenyl Ethane-1-one, anisole and the like. Examples of the acetophenone-based photopolymerization initiator include 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1-hydroxycyclohexylbenzene. Ketone, 4-phenoxydichloroacetophenone, 4- (thirdbutyl) dichloroacetophenone, and the like. Examples of the α-keto alcohol-based photopolymerization initiator include 2-methyl-2-hydroxyphenylacetone and 1- [4- (2-hydroxyethyl) phenyl] -2-methylpropane-1 -Ketones, etc. Examples of the aromatic sulfonyl chloride-based photopolymerization initiator include 2-naphthalenesulfonyl chloride and the like. Examples of the photoactive oxime-based photopolymerization initiator include 1-phenyl-1,1-propanedione-2- (o-ethoxycarbonyl) -oxime. Examples of the benzoin-based photopolymerization initiator include benzoin. Examples of the benzophenazine-based photopolymerization initiator include benzophenazine and the like. Examples of the benzophenone-based photopolymerization initiator include benzophenone, benzophenonebenzoic acid, 3,3'-dimethyl-4-methoxybenzophenone, and polyethylenedibenzene. Methyl ketone, α-hydroxycyclohexylphenyl ketone and the like. Examples of the ketal-based photopolymerization initiator include benzophenone dimethyl ketal and the like. As the above 9-oxysulfur Examples of photopolymerization initiators include 9-oxysulfur , 2-chloro9-oxysulfur 2-methyl 9-oxysulfur 2,4-dimethyl 9-oxosulfur Isopropyl 9-oxysulfur 2,4-diisopropyl 9-oxysulfur Dodecyl 9-oxysulfur Wait.

The amount of the photopolymerization initiator used is not particularly limited. For example, it is larger than 100 parts by weight of all the monomer units (the total amount of monomer components constituting the acrylic polymer (A)) of the acrylic polymer (A). It is preferably 0.001 to 1 part by weight, and more preferably 0.01 to 0.50 part by weight.

The thermal polymerization initiator is not particularly limited, and examples thereof include azo. Based polymerization initiator, peroxide based polymerization initiator (for example, benzoylperoxide, third butyl peroxymaleate, etc.), redox based polymerization initiator, and the like. Among them, the azo-based polymerization initiator disclosed in Japanese Patent Laid-Open No. 2002-69411 is preferred. Examples of the azo-based polymerization initiator include 2,2'-azobisisobutyronitrile (hereinafter sometimes referred to as "AIBN") and 2,2'-azobis-2-methylbutyronitrile ( Hereinafter referred to as "AMBN"), 2,2'-azobis (2-methylpropanoic acid) dimethyl ester, 4,4'-azobis-4-cyanovaleric acid, and the like.

The amount of the thermal polymerization initiator used is not particularly limited. For example, in the case of the azo-based polymerization initiator, it is relative to all the monomer units of the acrylic polymer (A) (constituting the acrylic polymer). The total amount of the monomer components (A)) is 100 parts by weight, preferably 0.05 to 0.5 parts by weight, and more preferably 0.1 to 0.3 parts by weight.

[1-3. Carboxyl-containing monomers, etc.]

The optical adhesive layer of the present invention does not contain or substantially does not contain an acidic group-containing monomer as a monomer component constituting the base polymer. When the optical adhesive layer of the present invention is an acrylic adhesive layer, the optical adhesive layer of the present invention preferably does not substantially contain a carboxyl group-containing monomer as a unit constituting the acrylic polymer (A). Body composition. In addition, the so-called "substantially non-containing" refers to the situation of unavoidably mixing in without actively deploying. The carboxyl-containing monosystem refers to a monomer having at least one carboxyl group in the molecule. From the viewpoint of obtaining a more excellent anticorrosive effect, specifically, the content of the carboxyl group-containing monomer is preferably 0.05 with respect to the total amount (100 parts by weight) of the monomer components constituting the acrylic polymer (A). Substantially parts (for example, 0 to 0.05 parts by weight), more preferably 0.01 parts by weight (for example, 0 to 0.01 parts by weight), and still more preferably 0.001 parts by weight (for example, 0 to 0.001 parts by weight) may be referred to as substantially Does not contain. Examples of the carboxyl group-containing monomer include (meth) acrylic acid, itaconic acid, maleic acid, fumaric acid, butenoic acid, and methacrylic acid. The monomers include, for example, maleic anhydride-containing monomers such as maleic anhydride and itaconic anhydride.

Further, in the case where the optical adhesive layer of the present invention is an acrylic adhesive layer In terms of obtaining a more excellent anticorrosive effect, it is preferred that the optical adhesive layer of the present invention not only does not substantially contain a carboxyl group-containing monomer as a monomer component constituting the acrylic polymer (A), Furthermore, a monomer having an acidic group (such as a sulfo group and a phosphate group) other than a carboxyl group is not substantially contained as a monomer component constituting the acrylic polymer (A). That is, the acrylic polymer (A) is preferably a monomer component of its composition, and does not substantially contain any of a carboxyl group-containing monomer and another acid group-containing monomer. Specifically, the total amount of the carboxyl group-containing monomer and other acidic group-containing monomers as the monomer component constituting the acrylic polymer (A) is relative to the total monomer component constituting the acrylic polymer (A). (100 parts by weight), preferably 0.05 parts by weight or less (for example, 0 to 0.05 parts by weight), more preferably 0.01 parts by weight or less (for example, 0 to 0.01 parts by weight), and still more preferably 0.001 parts by weight (for example, 0 to 0 parts) 0.001 parts by weight) can be said to be substantially free.

From the same viewpoint, as the monomer component constituting a polymer other than the acrylic polymer (A) (for example, the acrylic polymer (B) described below), the optical adhesive layer of the present invention is also Preferably, it does not contain or does not substantially contain an acidic group containing monomer. For example, it is preferable not to contain a carboxyl group-containing monomer substantially. In addition, the meaning of "substantially not contained", the preferable degree, and monomers containing an acidic group other than a carboxyl group are the same as those of the monomer component constituting the acrylic polymer (A).

[1-4. Basic group-containing monomer]

The optical adhesive layer of the present invention preferably does not contain or substantially does not contain a monomer containing a basic group as a monomer component constituting the base polymer. For example, in the case where the optical adhesive layer of the present invention is an acrylic adhesive layer containing an acrylic polymer (A) as a base polymer, it is preferable not to substantially contain a monomer containing a basic group as a constituent. It is preferable that the monomer component of a polymer other than the acrylic polymer (A) does not substantially contain a monomer containing a basic group in the adhesive layer even when it is not a monomer component constituting various polymers. The physical aspect is also the same as in the case of the carboxyl group-containing monomer. In addition, the meaning of "substantially not contained" and the preferable degree are the same.

[1-5. Hydroxyl-containing monomer]

The so-called hydroxyl-containing monosystem refers to a monomer having at least one hydroxyl group in the molecule. The monomer having at least one hydroxyl group in the molecule and at least one carboxyl group in the molecule is a carboxyl group-containing monomer and not a hydroxyl group-containing monomer. The above-mentioned hydroxyl-containing monomer is not particularly limited, and specific examples thereof include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate. Hydroxybutyl, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, hydroxyoctyl (meth) acrylate, (meth) Hydroxy-containing (meth) acrylates such as hydroxydecyl acrylate, hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) acrylate; vinyl alcohol, allyl alcohol, and the like. Among these, as the hydroxyl-containing monomer, from the viewpoint of improving the compatibility of the benzotriazole-based compound, a hydroxyl-containing (meth) acrylate is preferred, and 2-hydroxyethyl acrylate (HEA) is more preferred. ), 2-hydroxypropyl (meth) acrylate (HPA), 4-hydroxybutyl acrylate (4HBA). In addition, a hydroxyl-containing monomer can be used individually or in combination of 2 or more types.

[1-6. Nitrogen atom-containing monomer]

The so-called nitrogen atom-containing single system refers to a monomer having at least one nitrogen atom in a molecule (within one molecule). However, the aforementioned hydroxyl-containing monomers do not include the aforementioned nitrogen atom-containing monomers. That is, in the present specification, a monomer having a hydroxyl group and a nitrogen atom in a molecule is included in a nitrogen atom-containing monomer. The monomer having at least one nitrogen atom in the molecule and at least one carboxyl group in the molecule is a carboxyl group-containing monomer and not a nitrogen atom-containing monomer.

As the nitrogen atom-containing monomer, from the viewpoint of improving the foaming and peeling resistance, N-vinyl cyclic amidines, (meth) acrylamides, and the like are preferred. The nitrogen atom-containing monomer may be used alone or in combination of two or more kinds.

As the N-vinyl cyclic amidine, from the viewpoint of improving the compatibility of the benzotriazole-based compound, the N-vinyl cyclic amidine is preferably represented by the following formula (2).

[Chemical 2]

(In formula (2), R ³ represents a divalent organic group)

R ³ in the formula (2) is a divalent organic group, preferably a divalent saturated hydrocarbon group or an unsaturated hydrocarbon group, and more preferably a divalent saturated hydrocarbon group (for example, an alkylene group having 3 to 5 carbon atoms).

As the N-vinyl cyclic amidine represented by the above formula (2), N-vinyl-2 is preferred from the viewpoint of improving the foaming peel resistance and the compatibility of the benzotriazole-based compound. -Pyrrolidone (NVP), N-vinyl-2-piperidone, N-vinyl-2-caprolactam, N, N-dimethyl (meth) acrylamide, N, N- Diethyl (meth) acrylamide, N-vinyl-3-morpholinone, N-vinyl-1,3- 2-ketone, N-vinyl-3,5-morpholinedione, etc., more preferably N-vinyl-2-pyrrolidone, N-vinyl-2-caprolactam, N, N- Dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, and more preferably N-vinyl-2-pyrrolidone.

Examples of the (meth) acrylamide include (meth) acrylamide, N-alkyl (meth) acrylamide, N, N-dialkyl (meth) acrylamide, and the like. Examples of the N-alkyl (meth) acrylamide include N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, and N-n-butyl (methyl) ) Acrylamide, N-octyl acrylamide and the like. Furthermore, the N-alkyl (meth) acrylamide includes dimethylaminoethyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, and diamine. (Meth) acrylamide having an amine group such as methylaminopropyl (meth) acrylamide. Examples of the N, N-dialkyl (meth) acrylamide include N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dipropyl (meth) acrylamide, N, N-diisopropyl (meth) acrylamide, N, N-di (n-butyl) (meth) acrylamide, N , N-bis (third butyl) (methyl) Acrylamide and so on.

The (meth) acrylamide includes, for example, various N-hydroxyalkyl (meth) acrylamide. Examples of the N-hydroxyalkyl (meth) acrylamide include N-hydroxymethyl (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N -(2-hydroxypropyl) (meth) acrylamide, N- (1-hydroxypropyl) (meth) acrylamide, N- (3-hydroxypropyl) (meth) acrylamide, N- (2-hydroxybutyl) (meth) acrylamide, N- (3-hydroxybutyl) (meth) acrylamide, N- (4-hydroxybutyl) (meth) acrylamide , N-methyl-N-2-hydroxyethyl (meth) acrylamide and the like.

The (meth) acrylamide includes, for example, various N-alkoxyalkyl (meth) acrylamide. Examples of the N-alkoxyalkyl (meth) acrylamide include N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, and the like .

In addition, examples of the nitrogen atom-containing monomer other than the N-vinyl cyclic amidine and the (meth) acrylamido may include, for example, aminoethyl (meth) acrylate, (meth) acrylic acid Amino group-containing monomers such as dimethylaminoethyl ester, dimethylaminopropyl (meth) acrylate, and tributylaminoethyl (meth) acrylate; acrylonitrile, methacrylonitrile, etc. Cyano-containing monomers; (meth) acrylic morpholine, N-vinylpiper , N-vinylpyrrole, N-vinylimidazole, N-vinylpyrrole , N-vinylmorpholine, N-vinylpyrazole, vinylpyridine, vinylpyrimidine, vinyl Azole, vinyl iso Azole, vinyl thiazole, vinyl isothiazole, vinyl , (Meth) acryl pyrrolidone, (meth) acryl pyrrolidone, (meth) acryl pyridin, N-methyl vinyl pyrrolidone and other heterocyclic monomers; N-cyclohexyl Maleimide such as maleimide, N-isopropyl maleimide, maleimide, N-lauryl maleimide, maleimide, etc. Imine-based monomer, N-methyl itacantimine, N-ethyl itacantimine, N-butyl itacantimine, N-octyl itacantimine, N-2- Ethylhexyl itaconate imine, N-lauryl itaconate imine, N-cyclohexyl itaconate imine and other itacene imide monomers, N- (meth) acrylic acid oxymethylene Succinimide, N- (meth) acryl-6-oxyhexamethylene succinimide, N- (meth) acryl 8-oxyoctamethylene succinimide, etc. Monoimide group-containing monomers such as succinimide-based monomers; isocyanate group-containing monomers such as 2- (meth) propenyloxyethyl isocyanate; and the like.

[1-7. Other copolymerizable monomers]

As the copolymerizable monomer in the acrylic polymer (A), in addition to the nitrogen atom-containing monomer and the hydroxyl group-containing monomer, for example, an alkoxyalkyl (meth) acrylate [for example, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 3-methoxy (meth) acrylate Propyl ester, 3-ethoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate, etc.]; epoxy-containing monomers [Such as glycidyl (meth) acrylate, methyl glycidyl (meth) acrylate, etc.]; monomers containing a sulfonic acid group [eg, sodium vinylsulfonate, etc.]; monomers containing a phosphoric acid group; (Meth) acrylates of alicyclic hydrocarbon groups [e.g. cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, isomethacrylate Esters, etc.]; (meth) acrylates having aromatic hydrocarbon groups [e.g. phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, etc.]; vinyl esters Type [such as vinyl acetate, vinyl propionate, etc.]; aromatic vinyl compounds [such as styrene, vinyl toluene, etc.]; olefins or diene [such as ethylene, propylene, butadiene, isoprene, Isobutylene, etc.]; vinyl ethers [e.g. vinyl alkyl ether, etc.]; vinyl chloride, etc.

Furthermore, as a copolymerizable monomer in the said acrylic polymer (A), a polyfunctional monomer is also mentioned. The polyfunctional monomer functions as a crosslinking component. Examples of the polyfunctional monomer include hexanediol di (meth) acrylate, butanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, and (poly) ) Propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, allyl (meth) acrylate, vinyl (meth) acrylate, divinylbenzene, epoxy Acrylate, polyester acrylate, urethane acrylate, etc. Moreover, the polyfunctional monomer may be separated Use or use 2 or more types together.

The content (ratio) of the above-mentioned polyfunctional monomer in all the monomer units of the acrylic polymer (A) is not particularly limited, and it is relative to the total amount (100 parts by weight) of the monomer components constituting the acrylic polymer (A). ), Preferably 0.5 parts by weight or less (for example, 0 to 0.5 parts by weight), more preferably 0 to 0.35 parts by weight, and even more preferably 0 to 0.2 parts by weight. When the content of the polyfunctional monomer is 0.5 parts by weight or less, the adhesive layer has an appropriate cohesive force, and it is easy to improve the adhesive force or the step absorptivity, so it is preferable. Moreover, when a cross-linking agent is used, a polyfunctional monomer may not be used, but when the cross-linking agent is not used, the content of the polyfunctional monomer is preferably 0.001 to 0.5 parts by weight, more preferably 0.001 to 0.35 parts by weight, and more preferably 0.002 to 0.2 parts by weight.

[1-8. Acrylic polymer (B)]

When the optical adhesive layer of the present invention contains an acrylic polymer (A) as a base polymer, the optical adhesive layer of the present invention preferably contains the acrylic polymer (A) and a weight average molecular weight of 1,000 to 30,000 acrylic polymers (B). When an acrylic polymer (B) is contained, since the adhesiveness of the interface of an adhesive sheet to a to-be-adhered body improves, it is easy to obtain strong adhesiveness, and it is easy to obtain the outstanding foaming and peeling resistance. In this specification, the "acrylic polymer (B) having a weight average molecular weight of 1,000 to 30,000" may be simply referred to as "acrylic polymer (B)".

As said acrylic polymer (B), the acrylic polymer which consists of (meth) acrylic acid ester which has a cyclic structure in a molecule | numerator as an essential monomer component is mentioned preferably, More preferably, it is mentioned An acrylic polymer composed of a (meth) acrylic acid ester having a cyclic structure in the molecule and an (meth) acrylic acid alkyl ester having a linear or branched alkyl group as an essential monomer component. That is, as the acrylic polymer (B), an acrylic polymer containing a (meth) acrylic acid ester having a cyclic structure in the molecule as a monomer unit is preferably exemplified, and more preferably, it is included in the molecule. (Meth) acrylic acid esters having a cyclic structure inside and (meth) acrylic acid alkyl esters having a linear or branched alkyl group as monomer monomers Yuan acrylic polymer.

The cyclic structure (ring) of the (meth) acrylic acid ester (hereinafter referred to as "ring-containing (meth) acrylic acid ester") having a cyclic structure in the molecule (within one molecule) is not particularly limited, It may be either an aromatic ring or a non-aromatic ring. Examples of the aromatic ring include an aromatic carbocyclic ring [for example, a monocyclic carbocyclic ring such as a benzene ring or a condensed carbocyclic ring such as a naphthalene ring], various aromatic heterocyclic rings, and the like. Examples of the non-aromatic ring include a non-aromatic aliphatic ring (non-aromatic alicyclic ring) [for example, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, and a cyclooctane ring. Isocycloalkane rings; cycloolefin rings such as cyclohexene rings, etc.], non-aromatic bridging rings [e.g., pinane, pinene, Alkanes Alkanes Bicyclic hydrocarbon rings in olefins, etc .; aliphatic hydrocarbon rings (bridged hydrocarbon rings) of three or more rings in adamantane, etc.], non-aromatic heterocycles [e.g. epoxy rings, oxetane rings , Oxetane ring, etc.] and the like.

Examples of the above-mentioned tricyclic or higher aliphatic hydrocarbon ring (bridged or higher tricyclic hydrocarbon ring) include, for example, a bicyclopentyl group represented by the following formula (3a) and a bicyclopentane group represented by the following formula (3b) Alkenyl, adamantyl represented by the following formula (3c), tricyclopentyl represented by the following formula (3d), tricyclopentenyl represented by the following formula (3e), and the like.

That is, examples of the ring-containing (meth) acrylate include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, and (meth) acrylic acid. Cycloalkyl (meth) acrylate, etc .; (Meth) acrylates having bicyclic aliphatic hydrocarbon rings, such as dialkyl esters; dicyclopentyl (meth) acrylate, dicyclopentyloxyethyl (meth) acrylate, and tricyclic (meth) acrylate Amyl ester, 1-adamantyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate, etc. have (Meth) acrylates of aliphatic hydrocarbon rings of three or more rings; aryl (meth) acrylates such as phenyl (meth) acrylate, aryloxy (meth) acrylates such as phenoxyethyl (meth) acrylate (Meth) acrylates and the like having an aromatic ring, such as arylalkyl (meth) acrylates, such as alkyl alkyl esters and benzyl (meth) acrylates. Among them, as the ring-containing (meth) acrylate, in particular, a (meth) acrylate containing a non-aromatic ring is preferred, and cyclohexyl acrylate (CHA) and cyclohexyl methacrylate are more preferred. Ester (CHMA), dicyclopentyl acrylate (DCPA), dicyclopentyl methacrylate (DCPMA), and further preferably dicyclopentyl acrylate (DCPA), dicyclopentyl methacrylate ( DCPMA). The (meth) acrylate containing a ring may be used alone or in combination of two or more kinds.

In the case of using a non-aromatic ring-containing (meth) acrylate with a (meth) acrylate having an aliphatic hydrocarbon ring having three or more rings (especially a bridged hydrocarbon ring having three or more rings), the It is preferable that it is difficult to cause polymerization inhibition. In addition, a compound having a dicyclopentyl group represented by the formula (3a) containing no unsaturated bond, an adamantyl group represented by the formula (3c), and a tricyclopentyl group represented by the formula (3d) is used. In the case of a meth) acrylate, the foaming and peeling resistance can be further improved, and the adhesion to a low-polar adherend such as polyethylene or polypropylene can be significantly improved.

The content (ratio) of the above-mentioned ring-containing (meth) acrylate in all monomer units of the acrylic polymer (B) (the total amount of monomer components constituting the acrylic polymer (B)) is not particularly limited, 10-90 weight part is preferable with respect to the total amount (100 weight part) of the monomer component which comprises an acrylic polymer (B), More preferably, it is 20-80 weight part. When the content of the ring-containing (meth) acrylate is 10 parts by weight or more, it is easy to improve the resistance to foaming and peeling. good. In addition, if the content is 90 parts by weight or less, the adhesive layer is suitable because it has appropriate flexibility, and it is easy to improve the adhesive force and the step absorbency.

Examples of the (meth) acrylic acid alkyl ester having a linear or branched alkyl group as a monomer unit of the acrylic polymer (B) include methyl (meth) acrylate and (methyl) ) Ethyl acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, second butyl (meth) acrylate, ( Tert-butyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, (meth) Isodecyl acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, ( Pentadecyl (meth) acrylate, cetyl (meth) acrylate, heptadecyl (meth) acrylate, stearyl (meth) acrylate, 19- (meth) acrylate Alkyl esters, (meth) propyl The alkyl carbon acid eicosyl ester having 1 to 20 atoms of (meth) acrylate and the like. Among them, in terms of good compatibility with the acrylic polymer (A), methyl methacrylate (MMA) is preferred. In addition, the said (meth) acrylic-acid alkylester can be used individually or in combination of 2 or more types.

The above-mentioned (meth) acrylic acid alkyl ester having a linear or branched alkyl group among all the monomer units of the acrylic polymer (B) (the total amount of monomer components constituting the acrylic polymer (B)) The content (ratio) is not particularly limited, and in terms of resistance to foaming and peeling, it is preferably 10 to 90% by weight based on the total amount of monomer components (100 parts by weight) constituting the acrylic polymer (B). It is more preferably 20 to 80 parts by weight, and still more preferably 20 to 60 parts by weight. If the content is 10 parts by weight or more, the adhesion to an adherend made of an acrylic resin or polycarbonate is particularly likely to be improved, and therefore, it is preferable.

As the monomer unit of the acrylic polymer (B), in addition to the above-mentioned ring-containing (meth) acrylate and the alkyl (meth) acrylate having a linear or branched alkyl group, Contains a monomer (copolymerizable monomer) copolymerizable with these monomers. The content (ratio) of the above-mentioned copolymerizable monomer in all the monomer units (the total amount of monomer components constituting the acrylic polymer (B)) of the acrylic polymer (B) is not particularly limited, and The total amount (100 parts by weight) of monomer components constituting the acrylic polymer (B) is preferably 49.9 parts by weight or less (for example, 0 to 49.9 parts by weight), and more preferably 30 parts by weight or less. Moreover, a copolymerizable monomer can be used individually or in combination of 2 or more types.

Examples of the above-mentioned copolymerizable monomer (the above-mentioned copolymerizable monomer constituting the acrylic polymer (B)) as the monomer unit of the acrylic polymer (B) include, for example, (meth) acrylic alkoxyalkyl Esters [e.g. 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 3-methyl (meth) acrylate Methoxypropyl, 3-ethoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, 4-ethoxybutyl (meth) acrylate, etc.]; containing a hydroxyl group ( Hydroxyl) monomers [e.g. 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate , 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, hydroxyalkyl (meth) acrylates, vinyl alcohol, allyl alcohol, etc.]; monomers containing fluorenylamine groups [ For example, (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamine Amine, N-butoxymethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide ]; Amine-containing monomers [e.g. aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, tertiary butylaminoethyl (meth) acrylate, etc.]; Monocyano monomers [such as acrylonitrile, methacrylonitrile, etc.]; sulfonic acid group-containing monomers [such as sodium vinyl sulfonate, etc.]; phosphate group-containing monomers [such as 2-hydroxyethylacrylic acid] Ester, etc.]; Isocyanate group-containing monomers [such as 2-methacryloxyethyl isocyanate, etc.], fluorenimine-containing monomers [cyclohexylcisbutenediamidoimide, isopropylcisbutyl Arylene diimide, etc.] and so on.

As described above, the acrylic polymer (B) is preferably a (meth) acrylic acid ester having a cyclic structure in the molecule and a (meth) acrylic acid alkyl group having a linear or branched alkyl group. An acrylic polymer having an ester as a monomer unit. Among these, an acrylic polymer containing a ring-containing (meth) acrylate and the aforementioned (meth) acrylic acid alkyl ester having a linear or branched alkyl group as monomer units is preferred. The acrylic polymer containing a ring-containing (meth) acrylate and an alkyl (meth) acrylate having a linear or branched alkyl group as the above-mentioned monomer units is more effective than an acrylic polymer. The amount of the ring-containing (meth) acrylate in the total monomer component (100 parts by weight) of (B) is not particularly limited, but is preferably 10 to 90 parts by weight, and more preferably 20 to 80 parts by weight. The content of the alkyl (meth) acrylate having a linear or branched alkyl group is not particularly limited, but is preferably 10 to 90 parts by weight, more preferably 20 to 80 parts by weight, and even more preferably 20 ~ 60 parts by weight.

Furthermore, as a particularly preferable specific structure of the acrylic polymer (B), examples include (1) selected from the group consisting of dicyclopentyl acrylate, dicyclopentyl methacrylate, cyclohexyl acrylate and methacrylic acid. An acrylic polymer having at least one monomer in a group consisting of cyclohexyl ester and (2) methyl methacrylate as a monomer unit. (1) Dicyclopentyl acrylate, dicyclopentyl methacrylate, acrylic acid in all monomer units of the acrylic polymer (B) in the acrylic polymer (B) which is particularly preferable as described above. The content of cyclohexyl ester and cyclohexyl methacrylate (when two or more are included, the total amount of these) relative to the total amount of monomer components (100 parts by weight) constituting the acrylic polymer (B) ) Is preferably 30 to 70 parts by weight, and (2) the content of methyl methacrylate is preferably 30 to 70 parts by weight. However, the said acrylic polymer (B) is not limited to the said specific structure.

The acrylic polymer (B) can be obtained by polymerizing the above-mentioned monomer components by a known or conventional polymerization method. Examples of the polymerization method of the acrylic polymer (B) include a solution polymerization method, an emulsion polymerization method, a block polymerization method, and a polymerization method (active energy ray polymerization method) using active energy ray irradiation. Among them, a block polymerization method and a solution polymerization method are preferred, and a solution polymerization method is more preferred.

In the polymerization of the acrylic polymer (B), various general solvents may be used. Examples of the solvent include esters such as ethyl acetate and n-butyl acetate; toluene, benzene, and the like Aromatic hydrocarbons; aliphatic hydrocarbons such as n-hexane and n-heptane; alicyclic hydrocarbons such as cyclohexane and methylcyclohexane; organics such as methyl ethyl ketone and methyl isobutyl ketone Solvent. In addition, the said solvent can be used individually or in combination of 2 or more types.

In the polymerization of the acrylic polymer (B), a known or commonly used polymerization initiator (for example, a thermal polymerization initiator or a photopolymerization initiator) may be used. Moreover, a polymerization initiator can be used individually or in combination of 2 or more types.

Examples of the thermal polymerization initiator include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis-2-methylbutyronitrile (AMBN), 2,2'- Azobis (2-methylpropanoic acid) dimethyl ester, 4,4'-azobis-4-cyanovaleric acid, 2,2'-azobis (4-methoxy-2,4- Dimethylvaleronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2 ' -Azo-based initiators such as azobis (2,4,4-trimethylpentane); benzamidine peroxide, tertiary butyl hydroperoxide, tertiary butyl peroxide, tertiary butyl peroxide Benzoyl peroxide, dicumyl peroxide, 1,1-bis (third butyl peroxide) -3,3,5-trimethylcyclohexane, 1,1-bis (peroxide Peroxide-based initiators such as tertiary butyl) cyclododecane and the like. When solution polymerization is performed, an oil-soluble polymerization initiator is preferably used. Moreover, a thermal polymerization initiator can be used individually or in combination of 2 or more types.

The amount of the thermal polymerization initiator used is not particularly limited, and it is, for example, 100 parts by weight with respect to all the monomer units (the total monomer component of the acrylic polymer (B)) constituting the acrylic polymer (B). It is 0.1 to 15 parts by weight.

The photopolymerization initiator is not particularly limited, and examples thereof include the same photopolymerization initiator as the photopolymerization initiator used in the polymerization of the acrylic polymer (A) listed above. . The amount of the photopolymerization initiator used is not particularly limited and may be appropriately selected.

In the polymerization of the acrylic polymer (B), a chain transfer agent may be used in order to adjust the molecular weight (specifically, to adjust the weight average molecular weight to 1,000 to 30,000). Examples of the chain transfer agent include 2-mercaptoethanol, α-thioglycerin, and 2,3- Dimercapto-1-propanol, octyl mercaptan, third nonyl mercaptan, dodecyl mercaptan (lauryl mercaptan), thirty-two dodecyl mercaptan, glycidyl mercaptan, thio Glycolic acid, methyl thioglycolate, ethyl thioglycolate, propyl thioglycolate, butyl thioglycolate, third butyl thioglycolate, 2-ethylhexyl thioglycolate Octyl thioglycolate, isooctyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, thioglycolate of ethylene glycol, thioethanol of neopentyl glycol Acid esters, thioglycolates of pentaerythritol, α-methylstyrene dimers, and the like. Among these, from the viewpoint of suppressing whitening of the adhesive sheet caused by humidification, α-thioglycerin and methyl thioglycolate are preferred, and α-thioglycerol is particularly preferred. The chain transfer agent may be used alone or in combination of two or more kinds.

The content (amount of use) of the above-mentioned chain transfer agent is not particularly limited, and is relative to 100 parts by weight of all the monomer units (the total monomer component of the acrylic polymer (B)) constituting the acrylic polymer (B). It is preferably 0.1 to 20 parts by weight, more preferably 0.2 to 15 parts by weight, and still more preferably 0.3 to 10 parts by weight. By setting the content (amount of use) of the chain transfer agent to the above range, an acrylic polymer having a weight average molecular weight of 1,000 to 30,000 can be easily obtained.

The weight average molecular weight (Mw) of the acrylic polymer (B) is 1,000 to 30,000, preferably 1,000 to 20,000, more preferably 1500 to 10,000, and even more preferably 2000 to 8000. Since the weight average molecular weight of the acrylic polymer (B) is 1,000 or more, the adhesion or retention characteristics are improved, and the resistance to foaming and peeling is improved. On the other hand, since the weight average molecular weight of the acrylic polymer (B) is 30,000 or less, it is easy to increase the adhesive force and improve the foaming and peeling resistance.

The weight average molecular weight (Mw) of the acrylic polymer (B) can be determined by GPC (Gel Permeation Chromatography) and polystyrene conversion. For example, a high-speed GPC device "HPLC-8120GPC" manufactured by Tosoh Corporation can be used for measurement under the following conditions.

Column: TSKgel SuperHZM-H / HZ4000 / HZ3000 / HZ2000

Solvent: Tetrahydrofuran

Flow rate: 0.6ml / min

The glass transition temperature (Tg) of the acrylic polymer (B) is not particularly limited, but is preferably 20 to 300 ° C, more preferably 30 to 300 ° C, and even more preferably 40 to 300 ° C. When the glass transition temperature of the acrylic polymer (B) is 20 ° C. or higher, the resistance to foaming and peeling is easily improved, and therefore, it is preferable. In addition, if the glass transition temperature of the acrylic polymer (B) is 300 ° C or lower, the adhesive layer has appropriate flexibility, and it is easy to obtain good adhesion or good step absorption, and it is easy to obtain excellent adhesion reliability. , So better.

The glass transition temperature (Tg) of the acrylic polymer (B) is a glass transition temperature (theoretical value) represented by the following formula.

1 / Tg = W ₁ / Tg ₁ + W ₂ / Tg ₂ + ... + W _n / Tg _n

In the above formula, Tg represents the glass transition temperature (unit: K) of the acrylic polymer (B), Tg _i represents the glass transition temperature (unit: K) when the monomer i forms a homopolymer, and W _i represents the monomer i Weight fraction in the total amount of monomer components (i = 1, 2, ... n).

As a Tg of the homopolymer of the monomer which comprises the said acrylic polymer (B), the value shown in Table 1 below can be used. In addition, as the Tg of the homopolymer of a monomer not described in Table 1, the value described in "Polymer Handbook" (3rd edition, John Wiley & Sons, Inc, 1989) can be used. Furthermore, as the Tg of a homopolymer of a monomer which is not described in the above-mentioned literature, a value obtained by the above-mentioned measurement method (peak top temperature of tan δ obtained by a viscoelasticity test) can be used.

In addition, the copolymer of "DCPMA / MMA = 60/40" in Table 1 means a copolymer of 60 parts by weight of DCPMA and 40 parts by weight of MMA.

The content of the acrylic polymer (B) in the case where the adhesive layer for optics of the present invention contains acrylic polymers (A) and (B) is not particularly limited, and it is based on 100 weight of the acrylic polymer (A). It is preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight, and even more preferably 2 to 10 parts by weight. That is, the content of the acrylic polymer (B) in the optical adhesive layer of the present invention is not particularly limited, and is preferably 1 to 100 parts by weight of all the monomer units of the acrylic polymer (A). 30 parts by weight, more preferably 2 to 20 parts by weight, and even more preferably 2 to 10 parts by weight. The content of the acrylic polymer (B) in the adhesive composition is not particularly limited. For example, it is preferably 1 to 30 parts by weight, more preferably 2 to 20 parts by weight based on 100 parts by weight of the monomer mixture. It is preferably 2 to 10 parts by weight. When the content of the acrylic polymer (B) is 1 part by weight or more, it is easy to obtain excellent adhesion and excellent foaming and peeling resistance, and therefore, it is preferable. Further, when the content of the acrylic polymer (B) is 30 parts by weight or less, it is easy to obtain excellent transparency and adhesion reliability.

The method for producing the above-mentioned adhesive layer containing the acrylic polymers (A) and (B) is not particularly limited. For example, it is produced by a method of adding a benzotriazole-based compound, an acrylic polymer (B), an additive, and the like to a monomer mixture forming the acrylic polymer (A) or a part of the polymer as necessary, and mixing them.

[1-9. Additives]

In the above-mentioned adhesive layer, a cross-linking agent, a cross-linking accelerator, a silane coupling agent, and an adhesion-imparting resin (pine resin, polyterpene resin, petroleum resin, etc.) may be included, as long as the characteristics of the present invention are not impaired. , Oil-soluble phenol, etc.), anti-aging agents, fillers, colorants (pigments or dyes, etc.), ultraviolet absorbers, antioxidants, chain transfer agents, plasticizers, softeners, surfactants, antistatic agents, etc. are well known Of additives. The above additives may be used alone or in combination of two or more.

When a cross-linking agent is included in the adhesive layer, the base polymer is cross-linked to increase the gel fraction, and it is easy to improve the resistance to foaming and peeling. For example, the acrylic polymer (especially the acrylic polymer (A)) can be cross-linked to easily increase the control of the gel fraction, and therefore, it is easy to improve the resistance to foaming and peeling. Examples of the cross-linking agent include isocyanate-based cross-linking agents, epoxy-based cross-linking agents, melamine-based cross-linking agents, and peroxide-based cross-linking agents. In addition to these, urea-based cross-linking agents and metals Alkoxide-based crosslinker, metal chelate-based crosslinker, metal salt-based crosslinker, carbodiimide-based crosslinker, An oxazoline-based crosslinking agent, an aziridine-based crosslinking agent, an amine-based crosslinking agent, and the like. Among them, in the case where the optical adhesive layer of the present invention is an adhesive layer containing an acrylic polymer (A) as a base polymer, an isocyanate-based cross-linking agent is preferred in terms of improving the foaming and peeling resistance. The crosslinking agent and the epoxy-based crosslinking agent are more preferably an isocyanate-based crosslinking agent. Moreover, a crosslinking agent can be used individually or in combination of 2 or more types.

Examples of the isocyanate-based cross-linking agent (multifunctional isocyanate compound) include lower aliphatic polymers such as 1,2-ethylene diisocyanate, 1,4-butene diisocyanate, and 1,6-hexamethylene diisocyanate. Isocyanates; cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylene diisocyanate and other alicyclic polyisocyanates; 2,4-toluene diisocyanate, 2, Aromatic polyisocyanates such as 6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, etc. Examples of the isocyanate-based crosslinking agent include trimethylolpropane / toluene diisocyanate adduct [manufactured by Polyurethane Industry (Japan), trade name "Coronate L"], trihydroxy Methylpropane / hexamethylene diisocyanate adduct [manufactured by Polyurethane Industry (Japan), trade name "Coronate HL"], trimethylolpropane / xylylene diisocyanate adduct Commercial products such as "Mitsui Chemical Co., Ltd., trade name" Takenate D-110N "].

Examples of the epoxy-based crosslinking agent (multifunctional epoxy compound) include N, N, N ', N'-tetraglycidyl-m-xylylenediamine, diglycidylaniline, and 1,3 -Bis (N, N-diglycidylaminomethyl) cyclohexane, 1,6-hexanediol diglycidyl ether, neo Pentylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, sorbitol polyglycidyl ether, glycerin polyglycidyl ether , Pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitan polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, three In addition to glycidyl-tris (2-hydroxyethyl) isocyanurate, resorcinol diglycidyl ether, and bisphenol-S-diglycidyl ether, there may be two in the molecule. Epoxy-based resins such as the above. Examples of the epoxy-based crosslinking agent include commercially available products such as "Tetrad C" manufactured by Mitsubishi Gas Chemical Co., Ltd., for example.

The content of the crosslinking agent in the optical adhesive layer is not particularly limited. For example, when the optical adhesive layer of the present invention is an adhesive layer containing an acrylic polymer (A) as a base polymer, With respect to 100 parts by weight of the acrylic polymer (A), it is preferably 0.001 to 10 parts by weight, and more preferably 0.01 to 5 parts by weight. When the content of the cross-linking agent is 0.001 parts by weight or more, the resistance to foaming and peeling is easily improved, so it is preferable. On the other hand, if the content of the cross-linking agent is 10 parts by weight or less, it is preferable that the adhesive layer has appropriate flexibility and is easy to improve the adhesive force.

If a silane coupling agent is included in the optical adhesive layer, it is easy to obtain excellent adhesion to glass (especially, excellent adhesion reliability to glass under high temperature and high humidity), so it is preferable. The silane coupling agent is not particularly limited, and examples thereof include γ-glycidyloxypropyltrimethoxysilane, γ-glycidyloxypropyltriethoxysilane, and γ-aminopropyltrimethoxysilane , N-phenyl-aminopropyltrimethoxysilane and the like. Among them, γ-glycidoxypropyltrimethoxysilane is preferred. Further, examples of the silane coupling agent include commercially available products such as the trade name "KBM-403" (manufactured by Shin-Etsu Chemical Industry Co., Ltd.). The silane coupling agent may be used alone or in combination of two or more kinds.

The content of the silane coupling agent in the optical adhesive layer is not particularly limited. For example, the optical adhesive layer in the present invention contains an acrylic polymer (A) as In the case of the adhesive layer of the base polymer, in terms of improving the bonding reliability to glass, it is preferably 0.01 to 1 part by weight, more preferably 0.03 to 100 parts by weight of the acrylic polymer (A). ~ 0.5 parts by weight.

[2. Adhesive sheet]

The adhesive sheet of the present invention may be any one as long as it has the above-mentioned optical adhesive layer (the optical adhesive layer of the present invention), and the other aspects are not particularly limited.

The adhesive sheet of the present invention may be a double-sided adhesive sheet with both sides becoming the surface of the adhesive layer, or a single-sided adhesive sheet with only one side becoming the surface of the adhesive layer. Among them, a double-sided adhesive sheet is preferred from the viewpoint of bonding two members to each other. In addition, in the case of "adhesive sheet" in this specification, it also includes a band-shaped person, that is, "adhesive tape." In addition, in this specification, the surface of an adhesive layer may be called "adhesive surface."

In the adhesive sheet of the present invention, a separator (release liner) may be provided on the adhesive surface until use.

The adhesive sheet of the present invention may be a so-called "substrate-free type" adhesive sheet (hereinafter sometimes referred to as a "substrate-free adhesive sheet") without a substrate (substrate layer), or a type with a substrate. (Hereinafter sometimes referred to as "adhesive sheet with base material"). Examples of the substrate-free adhesive sheet include a double-sided adhesive sheet including only the adhesive layer, or an adhesive layer including the adhesive layer and an adhesive layer other than the adhesive layer (sometimes referred to as “other adhesives”). Layer "). On the other hand, examples of the adhesive sheet with a substrate include an adhesive sheet having the above-mentioned adhesive layer on at least one side of the substrate. Among them, a substrate-free adhesive sheet (a substrate-free double-sided adhesive sheet) is preferable, and a substrate-free double-sided adhesive sheet including only the above-mentioned adhesive layer is more preferable. In addition, the "base material (base material layer)" does not include a separator that is peeled off when an adhesive sheet is used (attached).

The adhesive sheet of the present invention is preferably a substrate-free adhesive sheet. The reason is that if it is an adhesive sheet with a base material using a moisture-proof substrate, it is considered that the anti-corrosion function can be imparted to a certain extent, so the non-substrate adhesive sheet has a higher meaning of anti-corrosion function.

[2-1. Various physical properties of adhesive sheet]

The 180 ° peeling adhesive force of the adhesive sheet of the present invention to the glass plate (especially the 180 ° peeling adhesive force of the adhesive face to the glass plate provided by the above-mentioned adhesive layer (the optical adhesive layer of the present invention) is not particularly Limitation: If the adhesion force is high, from the viewpoint of obtaining sufficient adhesion to the metal surface and improving the corrosion resistance effect, it is preferably 8N / 20mm or more, more preferably 10N / 20mm or more, and even more preferably 12N / 20 mm or more, and more preferably 14 N / 20 mm or more. If the 180 ° peeling adhesion force of the adhesive sheet of the present invention to the glass plate is a fixed value or more, the adhesion to the glass and the suppression of the bulge in the step are more excellent. Furthermore, the upper limit of the 180 ° peeling adhesion force of the adhesive sheet of the present invention to the glass plate is not particularly limited, and for example, it is preferably 40N / 20mm, more preferably 60N / 20mm. The 180 ° peeling adhesion force to the glass plate was determined by the following measurement method of the 180 ° peeling adhesion force.

The glass plate is not particularly limited, and examples thereof include a brand name "soda lime glass # 0050" (manufactured by Songlang Glass Industry Co., Ltd.). Moreover, alkali-free glass, chemically strengthened glass, etc. are mentioned.

180 ° peeling adhesive force of the adhesive sheet of the present invention with respect to the acrylic plate (especially 180 ° peeling adhesive force of the adhesive surface provided by the above adhesive layer (the optical adhesive layer of the present invention) with respect to the acrylic plate) There is no particular limitation. If the adhesion force is high, it is preferably 10N / 20mm or more, more preferably 12N / 20mm or more, and further preferably, from the viewpoint of obtaining sufficient adhesion to the metal surface and improving the corrosion resistance effect. It is 14N / 20mm or more. If the 180 ° peeling adhesive force of the adhesive sheet of the present invention with respect to the acrylic board is 10N / 20mm or more, it is easy to obtain good adhesion to the acrylic board or suppression of bulge in a good step, so it is preferable . In addition, the upper limit of the 180 ° peeling adhesion force of the adhesive sheet of the present invention with respect to the acrylic plate is not particularly limited, and is, for example, 40N / 20mm, more preferably 60N / 20mm. The 180 ° peeling adhesive force for an acrylic plate can be determined by the following method for measuring the 180 ° peeling adhesive force.

The acrylic plate is not particularly limited, and examples thereof include a PMMA plate (commercial ("Acrylite", Mitsubishi Rayon Co., Ltd.), etc.

(A-1. 180 ° Peel Adhesion Measurement Method)

The adhesive surface of the adhesive sheet was adhered to the adherend, and crimping was performed under a crimping condition of 2 kg rollers and one round trip, and aged for 30 minutes at 23 ° C and 50% RH. After aging, the adhesive sheet was peeled from the adherend under conditions of 23 ° C, 50% RH and a tensile speed of 300 mm / min and a peeling angle of 180 ° in accordance with JIS Z 0237, and the 180 ° peeling adhesive force was measured ( N / 20mm).

(B. thickness)

The thickness (total thickness) of the adhesive sheet of the present invention is not particularly limited, but is preferably 12 to 350 μm, and more preferably 12 to 300 μm. If the thickness is fixed or more, peeling of the stepped portion is difficult to occur, so it is preferable. Further, if the thickness is less than or equal to a certain value, it is easy to maintain an excellent appearance at the time of manufacture, which is preferable. Furthermore, the thickness of the adhesive sheet of the present invention includes the thickness of the separator.

(C. Haze)

The haze (based on JIS K7136) of the adhesive sheet of the present invention is not particularly limited, but is preferably 1.0% or less, and more preferably 0.8% or less. When the haze is 1.0% or less, it is preferable because excellent transparency or excellent appearance can be obtained. In addition, regarding the above haze, for example, after the adhesive sheet is left in a normal state (23 ° C, 50% RH) for at least 24 hours, when the separator is provided, the separator is peeled off, and the adhesive sheet is pasted. Put it on a glass slide (for example, a total light transmittance of 91.8% and a haze of 0.4%), and use the obtained sample as a sample using a haze meter (manufactured by Murakami Color Technology Research Institute Co., Ltd., trade name "HM -150 ").

(D. Total light transmittance)

The total light transmittance (based on JIS K7361-1) of the adhesive sheet of the present invention in the visible wavelength region is not particularly limited, but is preferably 85% or more, and more preferably 88% or more. If the total light transmittance is 85% or more, it is preferable to obtain excellent transparency or excellent appearance. Furthermore, regarding the above-mentioned total light transmittance, for example, the adhesive sheet may be in a normal state. (23 ° C, 50% RH) for at least 24 hours, peel off the spacer when it has a spacer, and attach the adhesive sheet to a glass slide (for example, a total light transmittance of 91.8%, fog For those with a degree of 0.4%), the obtained sample was measured using a haze meter (Murakami Color Technology Research Institute Co., Ltd., trade name "HM-150") as a sample.

[2-2. Manufacturing method of adhesive sheet]

The adhesive sheet of the present invention is not particularly limited, and it is preferably produced according to a known or conventional manufacturing method. For example, when the adhesive sheet of the present invention is a substrate-free adhesive sheet, it is obtained by forming the above-mentioned adhesive layer (the optical adhesive layer of the present invention) on a separator by using the method described above. In addition, in the case where the adhesive sheet of the present invention is an adhesive sheet with a substrate, it can be obtained by directly forming the above-mentioned adhesive layer on the surface of the substrate (direct printing method), or by temporarily placing it on a separator. After the above-mentioned adhesive layer is formed, the above-mentioned adhesive layer is provided on the substrate so as to be transferred (adhered) to the substrate to obtain (transfer method).

[2-3. Adhesive layer of adhesive sheet]

The gel fraction (the ratio of the solvent-insoluble component) of the above-mentioned adhesive layer of the adhesive sheet of the present invention (the optical adhesive layer of the present invention) is not particularly limited, but is preferably 65 to 99%, more preferably 68 to 95%, more preferably 70 to 95%. If the gel fraction is 65% or more, the cohesive force of the above-mentioned adhesive layer is improved, foaming or peeling at the interface with the adherend in a high-temperature environment is suppressed, and excellent foaming and peeling resistance is easily obtained, which is preferable. Furthermore, if the gel fraction is 99% or less, it is preferable to obtain appropriate flexibility and further improve the adhesiveness.

(Gel fraction)

The said gel fraction (a ratio of a solvent-insoluble component) is the value calculated specifically, for example by the following "measurement method of a gel fraction."

Adhesive layer was taken from the self-adhesive sheet: about 0.1 g, covered with a porous tetrafluoroethylene sheet (trade name "NTF1122", manufactured by Nitto Denko Corporation) with an average pore diameter of 0.2 μm, and bundled with a kite string The weight at this time was measured, and this weight was set as the weight before immersion. In addition, the weight before dipping is the total weight of the adhesive layer (adhesive layer adopted above), the tetrafluoroethylene sheet, and the kite string. The total weight of the tetrafluoroethylene sheet and the kite string was also measured in advance, and this weight was set as the bag weight.

Next, a person who covered the adhesive layer with a tetrafluoroethylene sheet and bundled it with a kite string (referred to as a "sample") was placed in a 50 ml container filled with ethyl acetate, and left to stand at 23 ° C for 7 days. Thereafter, the sample was taken out of the container (after ethyl acetate treatment), transferred to an aluminum cup, and dried in a dryer at 130 ° C for 2 hours to remove the ethyl acetate. Then, the weight was measured, and the weight was set to be impregnated. After weight.

The gel fraction was calculated according to the following formula.

Gel fraction [% (wt%)] = (X-Y) / (Z-Y) × 100

In addition, the said gel fraction can be controlled based on the monomer composition of a base polymer (for example, an acrylic polymer (A) etc.), a weight average molecular weight, the usage-amount (addition amount) of a crosslinking agent, etc.

(300% tensile residual stress)

The 300% tensile residual stress of the above adhesive layer (the optical adhesive layer of the present invention) is not particularly limited, and is preferably 7 to ²⁵ N / cm ² , more preferably 7 to 20 N / cm ² , and even more preferably 7 to 16 N / cm ² , more preferably 7 to 14 N / cm ² . If the 300% tensile residual stress is 7 N / cm ² or more, it is easy to obtain good resistance to foaming and peeling, so it is preferable. In addition, if the 300% tensile residual stress is ²⁵ N / cm ² or less, a good stress relaxation property and a good step followability are easily obtained, which is preferable.

If the adhesive sheet of the present invention has the above-mentioned adhesive layer having a tensile residual stress of 300% within a specific range, it is easy to obtain excellent stress relaxation properties, and it is easy to exhibit excellent step followability. For example, it can follow well a large step difference (for example, a step difference having a height of about 45 μm, especially a step difference having a height of 20 to 50 μm).

The above-mentioned 300% tensile residual stress is that the adhesive layer is stretched in the longitudinal direction until the elongation (deformation) is 300% under the environment of 23 ° C, and the elongation is maintained, and the adhesive layer applied after 300 seconds from the end of stretching is determined The tensile load is a value (N / cm ² ) obtained by dividing the tensile load by the initial cross-sectional area (cross-sectional area before stretching) of the adhesive layer. Moreover, the initial elongation of the adhesive layer was 100%.

(thickness)

The thickness of the above-mentioned adhesive layer (especially the optical adhesive layer of the present invention) is not particularly limited, but is preferably 12 to 350 μm, and more preferably 12 to 300 μm. If the thickness is fixed or more, it is preferable because the step followability or subsequent reliability is improved. When the thickness is equal to or less than a certain value, it is particularly excellent in operability and manufacturability, and therefore, it is preferable.

(Production method)

The method for producing the above-mentioned adhesive layer (the optical adhesive layer of the present invention) is not particularly limited, and examples thereof include coating the above-mentioned adhesive composition on a substrate or a release liner as required. A method of drying, hardening, or drying and hardening.

In addition, the coating of the said adhesive composition can use a well-known coating method. For example, a gravure roll coater, a reverse roll coater, a contact roll coater, a dip roll coater, a bar coater, a blade coater, a sprayer, a notch wheel coater, a direct Coating machine such as coating machine.

[2-4. Other layers of adhesive sheet]

In addition to the above-mentioned adhesive layer (the optical adhesive layer of the present invention), the adhesive sheet of the present invention may have other layers. Examples of his layer include his adhesive layer (adhesive layer other than the above-mentioned adhesive layer), an intermediate layer, and an undercoat layer. The adhesive sheet of the present invention may have two or more other layers.

[2-5. Base material of adhesive sheet]

The substrate in the case where the adhesive sheet of the present invention is an adhesive sheet with a substrate is not particularly limited, and examples thereof include various optical films such as a plastic film, an anti-reflection (AR) film, a polarizing plate, and a retardation plate. Examples of the materials for the plastic film include polyester resins such as polyethylene terephthalate (PET), and acrylic trees such as polymethyl methacrylate (PMMA). Grease, polycarbonate, triacetyl cellulose (TAC), polyfluorene, polyarylate, polyimide, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, ethylene-propylene copolymer, trade name Plastic materials such as cyclic olefin polymers such as "Arton (cyclic olefin polymer, manufactured by JSR Corporation)" and trade names "Zeonor (cyclic olefin polymer, manufactured by Japan Zeon Corporation)". Moreover, these plastic materials can be used alone or in combination of two or more. In addition, the "base material" refers to a part to be adhered to the adherend together with the adhesive layer when the adhesive sheet is attached to the adherend. The "base material" does not include a separator (release liner) which is peeled off when the adhesive sheet is used (when attached).

The substrate is preferably transparent. The total light transmittance (based on JIS K7361-1) of the above substrate in the visible light wavelength region is not particularly limited, but is preferably 85% or more, and more preferably 88% or more. The haze (based on JIS K7136) of the substrate is not particularly limited, but is preferably 1.0% or less, and more preferably 0.8% or less. Examples of such transparent substrates include non-alignment films such as PET films, trade names "Arton", and trade names "Zeonor".

The thickness of the substrate is not particularly limited, but is preferably 12 to 500 μm, for example. The substrate may have any of a single layer and multiple layers. Moreover, the surface of the said base material can also perform well-known and conventional surface treatments, such as a physical treatment, such as a corona discharge treatment and a plasma treatment, and a chemical treatment, such as an undercoating treatment, suitably.

[2-6. Separator for adhesive sheet]

In the adhesive sheet of the present invention, a separator (release liner) may be provided on the adhesive surface until use. Furthermore, in the case where the adhesive sheet of the present invention is a double-sided adhesive sheet, each adhesive surface can be separately protected by two spacers, or can be wound into a single spacer with both sides becoming peeling surfaces. Protected in roller form. The separator is used as a protective material for the adhesive layer, and is peeled off when attached to the adherend. When the adhesive sheet of the present invention is a substrate-free adhesive sheet, the separator also functions as a support for the adhesive layer. Furthermore, it is not necessary to provide a spacer.

The separator is not particularly limited, and a conventional release paper or the like can be used. E.g Examples thereof include a substrate having a release treatment layer, a low-adhesion substrate containing a fluoropolymer, and a low-adhesion substrate containing a non-polar polymer. Examples of the substrate having the peeling treatment layer include a plastic film or paper that has been surface-treated with a peeling treatment agent such as a polysiloxane-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide. Examples of the fluorine-based polymer in the low-adhesion base material including the fluoropolymer include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, and tetrafluoroethylene-hexafluoropropylene. Copolymers, chlorofluoroethylene-vinylidene fluoride copolymers, etc. Examples of the non-polar polymer include olefin-based resins (for example, polyethylene, polypropylene, etc.). Polyester-based substrates (polyethylene terephthalate-based substrates, polynaphthalenes, etc.) may also be used. (E.g., formate substrate, polybutylene terephthalate substrate, etc.). Furthermore, the spacer can be formed by a known or conventional method. The thickness and the like of the separator are not particularly limited.

[2-7. Use of adhesive sheet, etc.]

Since the adhesive sheet of this invention has the said adhesive layer (the optical adhesive layer of this invention), it is excellent in adhesiveness and resistance to foaming and peeling. Furthermore, it has excellent stress relaxation properties and excellent step followability. Therefore, the bonding reliability is excellent, especially at high temperatures. In addition, it is excellent in suppressing the occurrence of undulations in a high-temperature environment.

Therefore, the adhesive sheet of the present invention is useful for an adherend which is prone to foam at the interface at high temperatures. For example, polymethyl methacrylate resin (PMMA) may contain unreacted monomers, and it is easy to generate foam due to foreign matter at high temperatures. In addition, polycarbonate (PC) easily generates outgassing of water and carbon dioxide at high temperatures. Since the adhesive sheet of the present invention has excellent resistance to foaming and peeling, it is also useful for a plastic adherend containing such a resin.

In addition, in addition to the adherend having a small linear expansion coefficient, the adhesive sheet of the present invention is also useful for an adherend having a large linear expansion coefficient. The adherend having a small linear expansion coefficient is not particularly limited, and examples thereof include glass plates (linear expansion coefficient: 0.3 × 10 ^-5 to 0.8 × 10 ^-5 / ° C), and polyterephthalic acid. Ethylene glycol substrate (PET film, linear expansion coefficient: 1.5 × 10 ^-5 to 2 × 10 ^-5 / ℃), etc. The adherend having a large linear expansion coefficient is not particularly limited, and examples thereof include a resin substrate having a large linear expansion coefficient, and more specifically, a polycarbonate resin substrate (PC, linear expansion). Coefficient: 7 × 10 ^-5 ~ 8 × 10 ^-5 / ℃), Polymethyl methacrylate resin substrate (PMMA, Linear expansion coefficient: 7 × 10 ^-5 ~ 8 × 10 ^-5 / ℃), Cycloolefin Polymer base material (COP, coefficient of linear expansion: 6 × 10 ^-5 to 7 × 10 ^-5 / ℃), trade name "Zeonor" (manufactured by Zeon Co., Ltd.), trade name "Arton" (JSR Co., Ltd. Manufacturing) etc.

The adhesive sheet of the present invention is more useful for bonding an adherend having a smaller linear expansion coefficient and an adherend having a larger linear expansion coefficient. Specifically, the adhesive sheet of the present invention can be preferably used for bonding a glass adherend (such as a glass plate, chemically strengthened glass, glass lens, etc.) with a resin substrate having a large linear expansion coefficient as described above.

In this way, the adhesive sheet of the present invention is more useful for the adherence of adherends of various materials, especially for the adherence of glass adherends and plastic adherends. Moreover, the plastic adherend may be an optical film such as a plastic film having an ITO (oxide of indium and tin) layer on the surface.

Furthermore, in addition to the adherend having a smooth surface, the adhesive sheet of the present invention is also useful for an adherend having a stepped surface. In particular, even if at least one of the glass adherend and the above-mentioned resin substrate having a large linear expansion coefficient has a step on the surface, the adhesive sheet of the present invention is suitable for the glass adherend and the resin substrate having a large linear expansion coefficient. Lamination is also useful.

For example, the adhesive sheet of the present invention is a laminated body composed of a PET film (polyethylene terephthalate support), an ITO layer, and a copper wiring. The ITO layer can be patterned and fixed on the adherend. It is preferable to use a laminated body having a structure in which metal wiring is connected to the pattern of the ITO. The reason is that the above-mentioned laminated body is composed of materials having different elastic modulus or linear expansion, and sometimes undulations occur in a high temperature environment, but the adhesive sheet of the present invention can effectively suppress the occurrence of undulations in a high temperature environment.

The adhesive sheet of the present invention can be preferably used in the manufacture of mobile electronic devices. Its original This is because the adhesive sheet of the present invention can suppress the occurrence of undulations in a high-temperature environment, and thus can easily manufacture a mobile electronic device with a good appearance of the display portion. Examples of the mobile electronic device include a mobile phone, a PHS (Personal Handy-phone System), a smart phone, a tablet (a tablet computer), a mobile computer (a mobile PC), and mobile information. Mobile radio receivers such as terminals (PDAs), electronic notebooks, mobile TVs or mobile radios, mobile game consoles, portable music players, portable DVD players, cameras such as digital cameras, video recording Model video cameras, etc.

The adhesive sheet of the present invention can be preferably used, for example, for attaching components or modules constituting a mobile electronic device to each other, or for fixing components or modules constituting a mobile electronic device to a casing. More specifically, examples include: bonding of cover glass or lens (especially glass lens) and touch panel or touch sensor, fixing of cover glass or lens (especially glass lens) to the casing, display panel Fixing to the case, fixing of input devices such as sheet-shaped keyboards or touch panels to the case, bonding of the protection panel and the case of the information display section, bonding of the cases to each other, and the case and the decorative sheet Bonding, fixing or bonding of various components or modules constituting mobile electronic equipment. In addition, in the present specification, a display panel refers to a structure composed of at least a lens (especially a glass lens) and a touch panel. In addition, the lens in this specification includes the concept of both a transparent body showing a refraction effect of light and a transparent body having no refraction effect of light. That is, the lens in this specification also includes only a window plate having no refractive effect.

Furthermore, the adhesive sheet of the present invention can be preferably used for optical applications. That is, the adhesive sheet of the present invention is preferably an optical adhesive sheet used in optical applications. More specifically, it is preferably used, for example, in applications for bonding optical members (optical member bonding applications) or manufacturing applications of products (optical products) using the above-mentioned optical members.

[3. Optical components]

As long as the optical member of the present invention is an optical member having at least the above-mentioned adhesive sheet and a substrate, the substrate is provided with metal wiring (for example, copper wiring) on at least one side, and the above is affixed to the surface of the substrate having the metal wiring Adhesive layer (optical of the present invention An adhesive layer is sufficient, and other aspects are not particularly limited. In addition, the above-mentioned adhesive sheet may be provided with a spacer on the adhesive surface until use. The above-mentioned adhesive sheet in the optical member of the present invention is an adhesive sheet during use, and therefore does not have a spacer.

From the viewpoint of obtaining a more excellent anticorrosive effect, the optical member preferably has the adhesive layer on the opposite side of the substrate having the metal wiring, and more preferably has the metal wiring on the substrate. The above-mentioned adhesive layer is stuck on the surface opposite to the side.

The material constituting the metal wiring is not particularly limited, and examples thereof include titanium, silicon, niobium, indium, zinc, tin, gold, silver, copper, aluminum, cobalt, chromium, nickel, lead, iron, palladium, platinum, Tungsten, zirconium, tantalum, hafnium and other metals. Furthermore, those containing two or more of these metals or alloys containing these metals as a main component may be mentioned. Among them, gold, silver, and copper are preferred in terms of conductivity, and copper is more preferred in terms of conductivity and cost. That is, the metal wiring is particularly preferably a copper wiring. In addition, the materials of the metal wiring constituting the touch panel described below are also the same.

The optical member refers to a member having optical characteristics (for example, polarization, light refraction, light scattering, light reflection, light transmission, light absorption, light refraction, optical rotation, and visibility). The substrate constituting the optical member is not particularly limited, and examples thereof include a substrate constituting a device (optical device) such as a display device (image display device), an input device, or a substrate used by such devices, and examples thereof include polarized light. Plate, wavelength plate, retardation plate, optical compensation film, brightness enhancement film, light guide plate, reflection film, anti-reflection film, hard coating film (film that is hard-coated on at least one side of a plastic film such as PET film), transparent Conductive film (e.g. plastic film with ITO layer on the surface (preferably ITO film such as PET-ITO, polycarbonate, cycloolefin polymer, etc.), etc.), design film, decorative film, surface protection plate, glass, lens, Color filters, transparent substrates (glass sensors, glass display panels (LCD, etc.), glass substrates such as glass plates with transparent electrodes, etc.), or further laminated substrates (sometimes collectively referred to as these "Functional film"), etc. In addition, the films may have a metal nanowire layer or be conductive. Polymer layer and so on. Furthermore, metal thin wires may be screen-printed on these films. Furthermore, the "plate" and "film" mentioned above respectively include a plate shape, a film shape, and a sheet shape. For example, the "polarizing film" includes a "polarizing plate" and a "polarizing plate". The "film" includes a film sensor and the like.

Examples of the display device include a liquid crystal display device, an organic EL (electroluminescence) display device, a PDP (plasma display panel), and electronic paper. Examples of the input device include a touch panel and the like.

The substrate constituting the optical member is not particularly limited, and examples thereof include a substrate (for example, a sheet shape) containing glass, acrylic resin, polycarbonate, polyethylene terephthalate, a cycloolefin polymer, a metal thin film, and the like. , Film-like or plate-like substrates, etc.). Furthermore, as described above, the "optical member" of the present invention includes a member (design film, decorative film, surface protective film, etc.) that maintains the visibility of the display device or input device and is responsible for decoration or protection.

If the adhesive sheet of the present invention is a substrate-attached adhesive sheet and the adhesive sheet constitutes a member having optical characteristics, the substrate can be treated in the same manner as the substrate, and the adhesive sheet can be considered as the optical member of the present invention.

The adhesive sheet of the present invention is a substrate-attached adhesive sheet. When the functional film is used as the substrate, the adhesive sheet of the present invention can also be used as a functional film having the above-mentioned adhesive agent on at least one side. Layer of "adhesive functional film".

Next, a specific example of a particularly preferable aspect of the optical member of the present invention will be described with reference to the schematic diagram of FIG. 1.

In FIG. 1 (A), there is described an optical member 1 which is an optical member having at least a substrate as an adhesive sheet 10 and a transparent conductive film 11. The transparent conductive film 11 has metal wiring 3 on one side, and the adhesive sheet 10 is pasted. It is bonded to the surface of the transparent conductive film 11 on the side having the metal wiring 3.

FIG. 1 (B) shows an optical member 1 which is an optical member having at least a substrate as an adhesive sheet 10 and a transparent substrate 12, and the transparent substrate 12 has metal wiring on one side. 3. Adhere the adhesive sheet 10 to the surface of the transparent substrate 12 on the side having the metal wiring 3.

In FIG. 1 (C), there is described an optical member 1 which is an optical member having at least a substrate as an adhesive sheet 10 and a film sensor 13. The film sensor 13 has metal wiring 3 on one side to make the adhesive sheet 10 is attached to the surface of the film sensor 13 on the side having the metal wiring 3.

[4. Touch Panel]

As long as the touch panel of the present invention is a touch panel having at least the above-mentioned adhesive sheet and a substrate, the substrate is provided with metal wiring (such as copper wiring) on one side, and the surface of the substrate having the metal wiring on the side is pasted The above-mentioned adhesive layer is sufficient, and other aspects are not particularly limited. Furthermore, the above-mentioned adhesive sheet in the touch panel of the present invention is an adhesive sheet during use, and therefore does not have a spacer.

As the touch panel, it is preferred that the optical member of the present invention and another optical member (which may or may not have the above-mentioned adhesive sheet, from the viewpoint of obtaining a more excellent anti-corrosion effect, preferably It has the above-mentioned adhesive sheet). The other optical member may be singular or plural.

In the case of the above aspect, the aspect of bonding the optical member of the present invention to the other optical member is not particularly limited, and examples include: (1) the optical device of the present invention is passed through the adhesive sheet of the present invention; A state in which the member is bonded to the other optical member, (2) a state in which the adhesive sheet of the present invention containing or constituting the optical member is bonded to the other optical member, and (3) a bonding sheet in the present invention On the other hand, the state where the optical member is bonded to a member other than the optical member, (4) the state where the adhesive sheet of the present invention including or constituting the optical member is bonded to a member other than the optical member, and the like. Furthermore, in the aspect (2), the adhesive sheet of the present invention is preferably a double-sided adhesive sheet whose substrate is an optical member (such as an optical film).

Next, a specific example of a particularly preferred aspect of the touch panel of the present invention will be described with reference to the schematic diagram of FIG. 2.

FIG. 2 (A) shows a touch panel having a transparent substrate 12a, an adhesive sheet 10a, a transparent conductive film 11, an adhesive sheet 10b, and a transparent substrate 12b connected to each other in the following order. Panel 2. The transparent conductive film 11 is provided with the metal wiring 3 on the surface on the side of the adhesive sheet 10a, and the adhesive sheet 10a is bonded on the surface of the transparent conductive film 11 on the side with the metal wiring 3. The transparent substrate 12a and the transparent substrate 12b are preferably glass, and the transparent conductive film 11 is preferably PET-ITO. The adhesive sheet 10b may or may not be the adhesive sheet of the present invention, but is preferably the adhesive sheet of the present invention.

FIG. 2 (B) illustrates a touch panel 2 having a transparent substrate 12a, an adhesive sheet 10, a polarizing plate 14a, a transparent substrate 12b, and a polarizing plate 14b in a state of being connected to each other in the following order. The transparent substrate 12a is provided with the metal wiring 3 on the surface on the side of the adhesive sheet 10, and the adhesive sheet 10 is bonded on the surface of the transparent substrate 12a on the side having the metal wiring 3. The transparent substrate 12a is preferably a cover glass sensor, and the transparent substrate 12b is preferably a glass display panel such as an LCD.

In FIG. 2 (C), the contacts having the transparent substrate 12a, the adhesive sheet 10a, the film sensor 13, the adhesive sheet 10b, the polarizing plate 14a, the transparent substrate 12b, and the polarizing plate 14b are described in a state of being connected to each other in the following order. Control panel 2. The film sensor 13 is provided with the metal wiring 3 on the surface on the side of the adhesive sheet 10 a, and the adhesive sheet 10 a is adhered on the surface of the film sensor 13 on the side with the metal wiring 3. The transparent substrate 12a is preferably glass, and the transparent substrate 12b is preferably a glass display panel such as an LCD. The adhesive sheet 10b may be composed of the optical adhesive layer of the present invention or may not be composed of the optical adhesive layer of the present invention, but is preferably composed of the optical adhesive layer of the present invention.

FIG. 2 (D) shows a state in which the transparent substrate 12a, the adhesive sheet 10a, the film sensor 13, the adhesive sheet 10b, the hard coat film 15, the adhesive sheet 10c, the polarizing plate 14a, and the transparent substrate 12a The touch panel 2 of the substrate 12b and the polarizing plate 14b. The film sensor 13 is provided with the metal wiring 3 on the surface on the side of the adhesive sheet 10 a, and the adhesive sheet 10 a is adhered on the surface of the film sensor 13 on the side with the metal wiring 3. The transparent substrate 12a is preferably glass, the transparent substrate 12b is preferably a glass display panel such as an LCD, and the hard coating film 15 is preferably a hard coating PET film. Each of the adhesive sheets 10b and 10c may be composed of the optical adhesive layer of the present invention, or may not be composed of the optical adhesive layer of the present invention, but is preferably formed of the optical adhesive layer of the present invention. Make up.

FIG. 2 (E) shows an optical member 4 including a transparent substrate 12a, an adhesive sheet 10a, a film sensor 13, an adhesive sheet 10b, and a hard coating film 15 in a state of being connected to each other in the following order, and the following The touch panel 2 includes the polarizing plate 14a, the transparent substrate 12b, and the optical member 5 of the polarizing plate 14b in a state of being sequentially connected to each other. The optical member 4 and the optical member 5 have a positional relationship in which the hard coating film 15 and the polarizing plate 14 a face each other. The hard coating film 15 is not in contact with the polarizing plate 14a, and an air layer is formed between the hard coating film 15 and the polarizing plate 14a. The film sensor 13 is provided with the metal wiring 3 on the surface on the side of the adhesive sheet 10 a, and the adhesive sheet 10 a is adhered on the surface of the film sensor 13 on the side with the metal wiring 3. The transparent substrate 12a is preferably glass, the transparent substrate 12b is preferably a glass display panel such as an LCD, and the hard coating film 15 is preferably a hard coating PET film. The adhesive sheets 10b and 10c may each be composed of the optical adhesive layer of the present invention or may not be composed of the optical adhesive layer of the present invention, but are preferably composed of the optical adhesive layer of the present invention.

The metal wiring pattern (a wiring example of the metal wiring) is not particularly limited, and examples thereof include the metal wiring pattern shown in FIG. 7. FIG. 7 is a schematic plan view showing an example of a metal wiring pattern. In FIG. 7, 71a to 76a are metal wiring (pattern wiring), 71b to 76b are metal wiring (pattern wiring), and 81 to 86 electrodes (transparent electrodes). Each electrode is connected to a metal wiring. For example, the electrode 81 is connected to the metal wiring 71a and the metal wiring 72b. In addition, although each electrode is patterned into a strip shape in FIG. 7, the shape of the electrode is not limited to the strip shape. Further, in FIG. 7, each electrode is connected to the metal wiring at two locations, and the number of connection locations of the metal wiring in the electrodes is not particularly limited. For example, the electrode may be connected to the metal wiring at one location, or may be connected to the metal wiring at more than three locations. Furthermore, if necessary, metal wiring can be connected to a control mechanism such as an IC.

The method for forming the metal wiring pattern is not particularly limited, and examples thereof include a method for removing a metal layer provided in advance by etching, or a printing method.

[Example]

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited at all by these examples.

(Production Example 1 of acrylic polymer)

60 parts by weight of dicyclopentyl methacrylate (DCPMA, dicyclopentyl methacrylate), 40 parts by weight of methyl methacrylate (MMA, methyl methacrylate), and α- 3.5 parts by weight of thioglycerin and 100 parts by weight of toluene as a polymerization solvent were put into a four-necked flask, and these were stirred at 70 ° C. for 1 hour in a nitrogen atmosphere. Next, 0.2 parts by weight of 2,2'-azobisisobutyronitrile as a polymerization initiator was put into a four-necked flask and reacted at 70 ° C for 2 hours, and the reaction was continued at 80 ° C for 2 hours. Thereafter, the reaction solution was charged under a temperature environment of 130 ° C, and toluene, a chain transfer agent, and unreacted monomers were dried and removed to obtain a solid acrylic polymer. This acrylic polymer is referred to as "acrylic polymer (B-1)".

The weight average molecular weight (Mw) of the acrylic polymer (B-1) was 5.1 × 10 ³ .

[Example 1]

It consists of 68 parts by weight of 2-ethylhexyl acrylate (2EHA), 14.5 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 17.5 parts by weight of 2-hydroxyethyl acrylate (HEA). 0.035 parts by weight of a photopolymerization initiator (trade name "Irgacure 184", manufactured by BASF) and 0.035 parts by weight of a photopolymerization initiator (trade name "Irgacure 651", manufactured by BASF) are added to the polymer mixture, and then ultraviolet rays are irradiated. Until the viscosity (BH viscometer No. 5 rotor, 10 rpm, measurement temperature 30 ℃) becomes about 20Pa. Up to s, a prepolymer composition in which a part of the monomer components are polymerized is obtained.

Next, to 100 parts by weight of the prepolymer composition, 5 parts by weight of the acrylic polymer (B-1), 0.075 parts by weight of hexanediol diacrylate (HDDA), and a silane coupling agent (trade name "KBM- 403 ", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) 0.3 parts by weight, and 1,2,3-benzotriazole (trade name" BT-120 ", manufactured by Chengbei Chemical Industry Co., Ltd.) 0.05 parts by weight and mixed to obtain Adhesive composition (pre-curing composition).

The above-mentioned adhesive composition was applied to a polyethylene terephthalate (PET) separator (trade name "MRF50", manufactured by Mitsubishi Resin Co., Ltd.) so that the final thickness (thickness of the adhesive layer) became 100 μm. A coating layer (adhesive composition layer) is formed thereon. Then, a PET separator (trade name "MRF38", manufactured by Mitsubishi Resin Co., Ltd.) was provided on the coating layer, and the coating layer was covered to block oxygen. A multilayer body of MRF50 / coating layer (adhesive composition layer) / MRF38 was obtained.

Next, for this laminated body, from the upper surface (MRF38 side) of the laminated body, black light (manufactured by Toshiba Corporation) was irradiated with ultraviolet light having an illuminance of 5 mW / cm ² for 300 seconds. Furthermore, a drying process was performed for 2 minutes with a 90 degreeC dryer, and the residual monomer was volatilized. In addition, a substrate-free double-sided adhesive sheet containing only an adhesive layer and protecting both sides of the adhesive layer with a separator was obtained.

[Example 2]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the used amount of 1,2,3-benzotriazole was 0.1 parts by weight.

[Example 3]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the used amount of 1,2,3-benzotriazole was 0.2 parts by weight.

[Example 4]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the amount of 1,2,3-benzotriazole used was 0.3 parts by weight and the thickness of the adhesive layer was 50 μm. .

[Example 5]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the used amount of 1,2,3-benzotriazole was 0.3 parts by weight.

[Example 6]

The amount of 1,2,3-benzotriazole used is 0.3 parts by weight, and the thickness of the adhesive layer is set A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the thickness was 150 μm.

[Example 7]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the amount of 1,2,3-benzotriazole used was 0.3 parts by weight and the thickness of the adhesive layer was 250 μm. .

[Example 8]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1, except that the used amount of 1,2,3-benzotriazole was set to 0.5 parts by weight.

[Example 9]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the used amount of 1,2,3-benzotriazole was 2.0 parts by weight.

[Example 10]

Instead of 1,2,3-benzotriazole, 0.5 parts by weight of 5-methylbenzotriazole (trade name "5M-BTA", manufactured by Chengbei Chemical Industry Co., Ltd.) was used. In the same manner, a substrate-free double-sided adhesive sheet was obtained.

[Example 11]

Instead of 1,2,3-benzotriazole, 0.5 parts by weight of 1- [N, N-bis (2-ethylhexyl) aminomethyl] benzotriazole (trade name "BT-LX", Except for Seihoku Chemical Industry Co., Ltd., except having obtained the same manner as in Example 1, a substrate-free double-sided adhesive sheet was obtained.

[Example 12]

Instead of 1,2,3-benzotriazole, 0.5 parts by weight of 1- [N, N-bis (2-ethylhexyl) aminomethyl] methylbenzotriazole (trade name "TT-LX ", Manufactured by Seongbuk Chemical Industry Co., Ltd.), except that a substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1.

[Example 13]

The use amount of 1,2,3-benzotriazole was set to 0.3 parts by weight, and The composition was 61 parts by weight of 2-ethylhexyl acrylate (2EHA), 14 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 25 parts by weight of 4-hydroxybutyl acrylate (4HBA). A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the amount of hexanediol diacrylate (HDDA) was set to 0.060 parts by weight.

[Example 14]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that the used amount of 1,2,3-benzotriazole was 5.0 parts by weight.

[Example 15]

The use amount of 1,2,3-benzotriazole was set to 0.5 parts by weight, the acrylic polymer (B-1) was not used, and the composition of the monomer mixture was set to 2-ethylhexyl acrylate (2EHA ) In the same manner as in Example 1, except that 78 parts by weight, 18 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 4 parts by weight of 2-hydroxyethyl acrylate (HEA) were obtained, Substrate double-sided adhesive sheet.

[Example 16]

Hexylene glycol diacrylate (HDDA) was set to 0.250 parts by weight, and 1,2,3-benzotriazole (trade name "BT-120", manufactured by Chengbei Chemical Industry Co., Ltd.) was set to 0.3 parts by weight. Other than that, an adhesive composition (pre-curing composition) was obtained in the same manner as in Example 1.

And, using this composition, in the same manner as in Example 1, a substrate-free double-sided adhesive sheet containing only an adhesive layer and protecting both sides of the adhesive layer with a separator was obtained.

[Example 17]

61 parts by weight of 2-ethylhexyl acrylate (2EHA), 14 parts by weight of N-vinyl-2-pyrrolidone (NVP), 3 parts by weight of 2-hydroxyethyl acrylate (HEA), and 4- A prepolymer composition in which a part of the monomer components was polymerized was obtained in the same manner as in Example 1 except that a monomer mixture composed of 22 parts by weight of hydroxybutyl ester (4HBA) was used.

Next, hexanediol diacrylate was added to 100 parts by weight of the prepolymer composition. (HDDA) 0.180 parts by weight, silane coupling agent (trade name "KBM-403", manufactured by Shin-Etsu Chemical Co., Ltd.), 0.3 parts by weight, and 1,2,3-benzotriazole (trade name "BT-120" , Manufactured by Chengbei Chemical Industry Co., Ltd.) 0.3 parts by weight and mixed to obtain an adhesive composition (pre-curing composition).

And, using this adhesive composition, in the same manner as in Example 1, a substrate-free double-sided adhesive sheet containing only an adhesive layer and protecting both sides of the adhesive layer with a separator was obtained.

[Example 18]

61 parts by weight of 2-ethylhexyl acrylate (2EHA), 14 parts by weight of N-vinyl-2-pyrrolidone (NVP), 3 parts by weight of 2-hydroxyethyl acrylate (HEA), and 4- A prepolymer composition in which a part of the monomer components was polymerized was obtained in the same manner as in Example 1 except that a monomer mixture composed of 22 parts by weight of hydroxybutyl ester (4HBA) was used.

Next, to 100 parts by weight of the prepolymer composition, 0.060 parts by weight of hexanediol diacrylate (HDDA) and 0.3 parts by weight of a silane coupling agent (trade name "KBM-403", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) were added. And 0.3 parts by weight of 1,2,3-benzotriazole (trade name "BT-120", manufactured by Chengbei Chemical Industry Co., Ltd.) and mixed to obtain an adhesive composition (pre-curing composition).

And, using this composition, in the same manner as in Example 1, a substrate-free double-sided adhesive sheet containing only an adhesive layer and protecting both sides of the adhesive layer with a separator was obtained.

[Comparative Example 1]

A substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1 except that 1,2,3-benzotriazole was not used.

[Comparative Example 2]

0.5 parts by weight of pentaerythritol tetra [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] was used instead of 1,2,3-benzotriazole] (trade name "Irganox 1010" , Manufactured by BASF Co., Ltd.), except that a substrate-free double-sided adhesive sheet was obtained in the same manner as in Example 1.

[Comparative Example 3]

Without using 1,2,3-benzotriazole, without using the acrylic polymer (B-1), the composition of the monomer mixture was 90 parts by weight of 2-ethylhexyl acrylate (2EHA) and acrylic acid ( AA) In the same manner as in Example 1, except that 10 parts by weight was used, and 0.070 parts by weight of dipentaerythritol hexaacrylate (DPHA) was used instead of 0.075 parts by weight of hexanediol diacrylate (HDDA). Double-sided adhesive sheet.

[Comparative Example 4]

The use amount of 1,2,3-benzotriazole was set to 0.5 parts by weight, the acrylic polymer (B-1) was not used, and the composition of the monomer mixture was set to 2-ethylhexyl acrylate (2EHA ) 90 parts by weight and 10 parts by weight of acrylic acid (AA), and 0.070 parts by weight of dipentaerythritol hexaacrylate (DPHA) instead of 0.075 parts by weight of hexanediol diacrylate (HDDA). In the same manner, a substrate-free double-sided adhesive sheet was obtained.

[Comparative Example 5]

60 parts by weight of lauryl acrylate (LA), 22 parts by weight of 2-ethylhexyl acrylate (2EHA), 10 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 4-hydroxybutyl acrylate (4HBA) A prepolymer composition in which a part of the monomer components was polymerized was obtained in the same manner as in Example 1 except that a monomer mixture composed of 8 parts by weight was used.

Next, to 100 parts by weight of the prepolymer composition, 0.035 parts by weight of dipentaerythritol hexaacrylate (DPHA) and 0.3 parts by weight of a silane coupling agent (trade name "KBM-403", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) Then, they are mixed to obtain an adhesive composition (pre-curing composition).

And, using this composition, in the same manner as in Example 1, a substrate-free double-sided adhesive sheet containing only an adhesive layer and protecting both sides of the adhesive layer with a separator was obtained.

[Comparative Example 6]

The use amount of 1,2,3-benzotriazole was set to 0.3 parts by weight, and The composition is 60 parts by weight of lauryl acrylate (LA), 22 parts by weight of 2-ethylhexyl acrylate (2EHA), 10 parts by weight of N-vinyl-2-pyrrolidone (NVP), and 4-hydroxybutane acrylate In the same manner as in Example 1, except that 8 parts by weight of ester (4HBA) was used, and 0.035 parts by weight of dipentaerythritol hexaacrylate (DPHA) was used instead of 0.075 parts by weight of hexanediol diacrylate (HDDA). Substrate double-sided adhesive sheet.

[Characteristic evaluation]

The substrate-free double-sided adhesive sheets of the examples and comparative examples were measured or evaluated as described below. The evaluation results are shown in Table 2.

(1) metal corrosion

A copper layer film (hereinafter sometimes referred to as a “copper film”) is peeled off from one side of a cyclic olefin (COP) substrate (trade name “Zeonor”, manufactured by Zeon Corporation of Japan, thickness 100 μm). A separator on one side of the double-sided adhesive sheet. The double-sided adhesive sheet is crimped under a pressure of 2 kg rollers and pressed back and forth for bonding to obtain a structure having a laminated structure of a copper film and the double-sided adhesive sheet. A.

Next, after cutting the structure A to a size of 15 mm × 15 mm, the separator of the double-sided adhesive sheet was peeled off, and the pressure bonding was performed on a 2 kg roller under a crimping condition to make it adhere to a soda glass plate (25 mm × 25mm, thickness 0.7mm). Then, a structure B having a laminated structure of a copper film, a double-sided adhesive sheet, and glass was obtained.

In addition, a film having an anti-reflective treatment layer (trade name "DSC-03", manufactured by Dainippon Printing Co., Ltd.) is provided on one side of the triacetin cellulose (TAC) substrate, and is sometimes referred to as "AR Film ") on the substrate surface side, peeling off the separator on one side of the same double-sided adhesive sheet, and pressing and bonding the double-sided adhesive sheet under a pressure-bonding condition of 2 kg rollers and reciprocating once to obtain Structure C having a laminated structure of an AR film and a double-sided adhesive sheet. Next, the structure C was cut out to a size of 10 mm × 10 mm, and then the separator of the double-sided adhesive sheet was peeled off. The structure was then crimped under a crimping condition of 2 kg rollers and back and forth to make it adhere to the copper in the structure B. The AR film, double-sided adhesive sheet, copper film, double-sided adhesive sheet, and glass Structure D of 5 layers of glass.

After being left in an environment of 23 ° C and 50% RH for 30 minutes, the structure D was put into an autoclave, and the autoclave treatment was performed at a temperature of 50 ° C and a pressure of 0.5 MPa for 15 minutes. After the autoclave treatment, the structure D was taken out of the autoclave, and left in an environment of 23 ° C. and 50% RH (RH: relative humidity) for 24 hours.

As a device for measuring the sheet resistance value of the copper layer of the structure D, a Hall effect measuring device (trade name "HL5500PC", manufactured by Toho Technology) was used. The sheet resistance value (initial sheet resistance: R ₀ ) of the structure D was measured at 23 ° C. and 50% RH, respectively.

After the measurement, in order to prevent the oxidation of the copper in the part in contact with the measurement probe, they were put into 85 ° C and 85% RH environments for 300 hours while covering the copper surface of the structure D without the AR film. After taking out, the temperature and humidity were adjusted for 24 hours under the environment of 23 ° C and 50% RH. After visually confirming the color change from the initial copper, the sheet resistance values were measured under the environment of 23 ° C. and 50% RH (sheet resistance after the test: R ₁ ).

From the initial sheet resistance value (R ₀ ) and the sheet resistance value (R ₁ ) after the test was put into the environment of 85 ° C and 85% RH for 300 hours, the change of the sheet resistance value was calculated according to the following calculation formula Rate T.

Change rate T (%) = (R ₁ -R ₀ ) / R ₀ × 100

If the change rate T of the sheet resistance value does not reach 150%, it is set as a pass ("○"), and it is judged that it has good corrosion resistance. On the other hand, if the rate of change of the resistance value from the initial stage is 150% or more, it is regarded as unacceptable ("×"), and it is judged that it does not have good corrosion resistance.

(2) Total light transmittance and haze

The one-sided separator is peeled from the double-sided adhesive sheet, and the double-sided adhesive sheet is bonded to a glass slide (manufactured by Songlang Glass Industry Co., Ltd., "White Grinding No. 1", thickness 0.8 to 1.0 mm, and full light transmission (92%, haze 0.2%), and then peeled off the separator on the other side A test piece having a double-sided adhesive sheet (adhesive layer) / glass slide layer composition was prepared.

The haze meter (device name "HM-150", manufactured by Murakami Color Research Institute Co., Ltd.) was used to measure the total light transmittance and haze of the test piece in the visible light region.

(3) 180 ° peeling adhesion (180 ° peeling adhesion to glass plate)

A sheet with a length of 100 mm and a width of 20 mm was cut from the double-sided adhesive sheet. Then, a separator on one side was peeled from the sheet, and a PET film (trade name "Lumirror S-10", thickness 25 µm, manufactured by Toray Co., Ltd.) was attached (lined). Next, the separator on the other side was peeled off, and it was crimped to the test plate under a crimping condition of 2 kg rollers and one round trip. Thereafter, it was aged in an environment of 23 ° C. and 50% RH for 30 minutes. After aging, a tensile tester (device name "Autograph AG-IS", manufactured by Shimadzu Corporation) was used in accordance with JIS Z0237 in a 23 ° C, 50% RH environment at a tensile speed of 300 mm / min. The adhesive sheet was peeled from the test plate at an angle of 180 °, and the 180 ° peeling adhesive force (N / 20mm) was measured.

The test plate was a glass plate (trade name "Sodium Lime Glass # 0050", manufactured by Songlang Glass Industry Co., Ltd.).

(4) Resistance to humidification and white turbidity

After cutting the double-sided adhesive sheet into a width of 45mm and a length of 90mm, the separator on one side was peeled off and crimped under the condition of 2kg rollers and crimping once to make it adhere to a soda glass plate (Songlang Glass Industry) Co., Ltd., 100mm × 50mm, thickness 0.7mm). Next, the separator is peeled off from the above-mentioned double-sided adhesive sheet, and the same glass plate as above is obtained by using a vacuum bonding device under the conditions of a surface pressure of 0.2 MPa, a vacuum of 30 Pa, and a bonding time of 10 seconds. Evaluation sample of glass / double-sided adhesive sheet / glass composition.

Next, the above-mentioned evaluation sample was put into an autoclave, and an autoclave treatment was performed at a temperature of 50 ° C. and a pressure of 0.5 MPa for 15 minutes. After the autoclave treatment, the evaluation sample was taken out and left in an environment of 23 ° C. and 50% RH (RH: relative humidity) for 24 hours.

After putting the evaluation sample in a high-temperature and high-humidity environment at 60 ° C and 95% RH for 300 hours, After being taken out, it was left for 24 hours under the environment of 23 ° C and 50% RH, and then the appearance of the sample was evaluated by visual observation, and the moisturizing and turbidity resistance was evaluated according to the following evaluation criteria.

Evaluation benchmark

A: No whitening

B: Whitening is visible only at the four corners of the double-sided adhesive sheet

C: Whitening is visible on the entire surface of the double-sided adhesive sheet

(5) Resistance to foaming and peeling

The separator on one side of the double-sided adhesive sheet was peeled off, and the double-sided adhesive sheet was crimped under a crimping condition of 2 kg rollers and back and forth to make it adhere to a cyclic olefin (COP) substrate (trade name "Zeonor ", Manufactured by Zeon Co., Ltd., Japan, with a thickness of 100 µm) on one side of the ITO layer side of a film (hereinafter sometimes referred to as" COP-ITO film ") on which an ITO (oxide of indium and tin) layer is provided. In addition, a structure A ′ having a laminated structure of a COP-ITO film and a double-sided adhesive sheet was obtained.

Next, the separator of the double-sided adhesive sheet in the structure A 'is peeled off, and the structure A' is crimped on a 2 kg roller under a crimping condition of one round trip to make it adhere to the glass with step difference (Fig. 4). ~ 6 reference) on the side with step difference. Further, a structure B ′ having a laminated structure of a COP-ITO film, a double-sided adhesive sheet, and a stepped glass is obtained.

After the structure B ′ was left in an environment of 23 ° C. and 50% RH for 1 hour, the structure B ′ was put into an autoclave and subjected to an autoclave treatment at a temperature of 50 ° C. and a pressure of 0.5 MPa for 15 minutes. After the autoclave treatment, the structure B ′ was taken out from the autoclave, and the structure B ′ was put into a dryer set at 85 ° C. and left for 24 hours.

Then, the structure B 'was taken out from the dryer, and left for 30 minutes in an environment of 23 ° C and 50% RH. In addition, the presence or absence of foaming (including foaming caused by foreign matter) or peeling in the structure B 'was confirmed with a microscope. The evaluation was performed in accordance with the following evaluation criteria.

Evaluation benchmark

A: No foaming or peeling at all

B: Foaming caused only by foreign matter with a size of 100 μm or more can be seen

C: Foaming caused by foreign matter less than 100 μm

D: Foaming or peeling can be seen with or without foreign matter

In addition, the evaluation of the above-mentioned (5) resistance to foaming and peeling is also aimed at using ITO (indium and tin) on one side of a polyethylene terephthalate (PET) substrate (thickness: 50 μm) instead of the COP-ITO film. An oxide) layer (hereinafter sometimes referred to as a "PET-ITO film") is used.

(6) Visual evaluation of patterns

The thickness of the film substrate (a biaxially-stretched polyethylene terephthalate (PET) film with a thickness of 23 μm, trade name "Diafoil", manufactured by Mitsubishi Resins Co., Ltd.) was used to form a film by sputtering to form a thickness. A 22 nm ITO film (ITO layer) was obtained by forming an ITO film (ITO film) on one side of a film substrate.

Next, this ITO film was cut into a sheet shape having a width of 6 cm and a length of 10 cm. A plurality of polyimide tapes with a width of 2 mm were laminated on the surface of the cut ITO film at a distance of 2 mm. The bonding of the polyimide tape is performed so that the longitudinal direction of the polyimide tape and the width direction of the cut ITO film become the same direction. After bonding the polyimide tape, it was immersed in a 5 wt% hydrochloric acid aqueous solution heated to 50 ° C for 10 minutes. This immersion corresponds to an etching process for the purpose of removing the ITO film of the non-shielding portion (the portion where the polyimide tape is not attached). After being immersed in a 5 wt% hydrochloric acid aqueous solution, it was washed with water by immersing in a sufficient amount of pure water, and the polyimide tape was slowly peeled off.

Then, it was dried by heating in an oven at 70 ° C. for 5 minutes to obtain a film having a patterned ITO film (ITO pattern film).

The ITO pattern film includes a pattern forming portion in which an ITO film is formed and a pattern opening portion in which the ITO film is removed.

After the copper wiring is provided so as to be connected to the peripheral edge portion of the ITO pattern film-formed surface and the end portions of the respective patterns from the peripheral edge portion, a glass plate is bonded to the surface through a double-sided adhesive sheet to obtain Test piece (with ITO with glass plate / double-sided adhesive sheet / copper wiring) A laminated body of a laminated structure of a pattern film).

Furthermore, the copper wiring system provided so as to be connected to the peripheral edge portion of the ITO pattern film-formed surface and the end portion of each pattern from the peripheral edge portion corresponds to the state shown in FIG. 7.

Next, the test piece was left to stand in an environment of 85 ° C. and 85% RH for 48 hours. For the test piece after being left, the visibility of the pattern was visually confirmed, and evaluation was performed according to the following evaluation criteria.

Evaluation benchmark

Very good (◎): It is difficult to distinguish the pattern forming portion from the pattern opening, and almost no pattern is seen.

Good (○): The pattern forming portion and the pattern opening portion are slightly distinguished, and the pattern is slightly visible.

Defect (×): The pattern forming portion and the pattern opening portion can be clearly distinguished, and the pattern can be clearly seen.

[Industrial availability]

According to the optical adhesive layer of the present invention, adhesion reliability, transparency and anti-corrosion effects can be provided, and furthermore, fluctuations in a high-temperature environment can be suppressed, steps can be reduced without coating of a protective layer, and the cost can be reduced as a result. The yield is improved, so it is useful for display devices such as liquid crystal displays (LCD) and input devices such as touch panels, especially for touch panel applications.

Claims (15)

An adhesive layer for optics, comprising an acrylic polymer (A) and a benzotriazole-based compound, and containing an acrylic polymer (A) based on the total amount of monomer components (100 parts by weight) constituting the acrylic polymer (A). 0 to 0.05 parts by weight of a carboxyl group-containing monomer is used as a monomer component constituting the acrylic polymer (A), and the modulus of elasticity at 85 ° C is 5.0 × 10 ⁴ Pa or more. The total amount of monomer components (100 parts by weight) constituting the acrylic polymer (A) contains 0.02 to 3 parts by weight, the average molecular weight of the acrylic polymer (A) is 100,000 to 5000000, and the acrylic polymer (A) It contains (meth) acrylic acid alkyl esters and copolymerizable monomers as monomer units, and the content thereof is 30 to 95 parts by weight relative to the total amount of the monomer components constituting the acrylic polymer (A). And 5 to 40 parts by weight, the above (meth) acrylic acid alkyl ester is selected from methyl methacrylate (MMA), butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), and isomer of acrylic acid Aliphatic ester (ISTA). For example, the optical adhesive layer of Claim 1 contains 5 weight part or more with respect to the total amount (100 weight part) of the monomer component which comprises an acrylic polymer (A). For example, the optical adhesive layer according to claim 1 contains 5 parts by weight or more of a monomer containing a nitrogen atom with respect to the total amount (100 parts by weight) of monomer components constituting the acrylic polymer (A). If the optical adhesive layer according to any one of claims 1 to 3 has a haze (based on JIS K7136) of 1.0% or less. The optical adhesive layer according to any one of claims 1 to 3 has a total light transmittance (based on JIS K7361-1) of 90% or more. An adhesive sheet having the optical adhesive layer according to any one of claims 1 to 5. If the adhesive sheet of claim 6 has a 180 ° peel adhesion force to the glass plate, it is 8N / 20mm or more. If the adhesive sheet of claim 6 or 7 has a thickness of 12 to 350 μm. An optical member having at least the adhesive sheet and the substrate according to any one of claims 6 to 8, and the substrate is provided with metal wiring on at least one side, and is stuck on the surface of the substrate having the metal wiring side There are the above adhesive sheets. The optical member according to claim 9, wherein the metal wiring is a copper wiring. A touch panel comprising at least an adhesive sheet and a substrate according to any one of claims 6 to 8, and the substrate is provided with metal wiring on at least one side, and on a side of the substrate having the metal wiring The above-mentioned adhesive sheet is pasted. The touch panel according to claim 11, wherein the metal wiring is a copper wiring. If the optical adhesive layer according to any one of claims 1 to 3 further contains a photopolymerization initiator, the photopolymerization initiator is selected from the group consisting of benzoin-based photopolymerization initiator and acetophenone-based photopolymerization. Starter, α-keto alcohol-based photopolymerization initiator, aromatic sulfonyl chloride-based photopolymerization initiator, photoactive oxime-based photopolymerization initiator, benzoin-based photopolymerization initiator, benzoin Polymerization initiator, benzophenone-based photopolymerization initiator, ketal-based photopolymerization initiator, 9-oxysulfur The group of photopolymerization initiators contains 0.001 to 1 part by weight with respect to 100 parts by weight of all monomer units of the acrylic polymer (A) (the total amount of monomer components constituting the acrylic polymer (A)). One use is for bonding an optical adhesive layer for an optical member having metal wiring. The optical adhesive layer is characterized in that it contains a base polymer and a rust inhibitor. The total body composition (100 parts by weight), containing 0 to 0.05 parts by weight of an acidic group-containing monomer as the monomer component constituting the above-mentioned base polymer, and the elastic modulus at 85 ° C. is 5.0 × 10 ⁴ Pa or more. The adhesive layer forms an adhesive sheet, and the adhesive sheet is adhered to an optical member having metal wiring. A use for bonding an optical adhesive layer for an optical member having metal wiring, and the optical adhesive layer is characterized in that it contains an acrylic polymer (A) and a rust preventive, and the Total amount of monomer components of polymer (A) (100 parts by weight), containing 0 to 0.05 parts by weight of carboxyl group-containing monomers as monomer components constituting acrylic polymer (A), elastic modulus at 85 ° C When it is 5.0 × 10 ⁴ Pa or more, the adhesive layer forms an adhesive sheet, and the adhesive sheet is adhered to an optical member having metal wiring.