KR102281764B1 - Active energy ray-curable adhesive sheet and laminate - Google Patents

Abstract

Provided are an active energy ray-curable pressure-sensitive adhesive sheet and a laminate having a pressure-sensitive adhesive layer that is excellent in step tracking property and also excellent in moisture and heat whitening resistance, durability and blister resistance.
As the pressure-sensitive adhesive sheet 1 having an active energy ray-curable pressure-sensitive adhesive layer 11, the pressure-sensitive adhesive layer 11 with respect to the storage modulus at 23° C. before irradiating the pressure-sensitive adhesive layer 11 with an active energy ray. The ratio of the storage modulus at 23° C. after irradiation with active energy rays is 1.1 to 10, and the both sides of the pressure-sensitive adhesive layer 11 are sandwiched between two sheets of alkali-free glass having a thickness of 1.1 mm, and the active energy rays are passed through one glass. The haze value (%) before the wet heat condition from the haze value (%) when the irradiated laminate was stored for 240 hours under a moist heat condition of 85 ° C. and 85% RH, and then taken out at 23 ° C., 50% RH under normal temperature and humidity. An active energy ray-curable pressure-sensitive adhesive sheet (1), characterized in that the haze value rise after the wet heat condition, which is a value obtained by subtracting , is less than 5.0 points.

Description

Active energy ray-curable adhesive sheet and laminate

The present invention relates to a pressure-sensitive adhesive sheet having an active energy ray-curable pressure-sensitive adhesive layer, and a laminate obtained by using the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet.

Various mobile electronic devices such as mobile phones and tablet terminals in recent years are equipped with displays using display modules including liquid crystal elements, light emitting diodes (LED elements), organic electroluminescence (organic EL) elements, and the like.

In such a display, the protective panel is normally provided in the surface side of a display body module. Between the protective panel and the display module, even when the protective panel is deformed by an external force, a gap is provided so that the deformed protective panel does not collide with the display module.

However, if there is an air gap, that is, an air layer as described above, the reflection loss of light due to the difference in refractive index between the protective panel and the air layer and the difference in refractive index between the air layer and the display module is large, so that the image quality of the display is deteriorated. there is.

Therefore, it has been proposed to improve the image quality of the display by filling the gap between the protective panel and the display module with an adhesive layer. However, on the display module side of the protection panel, a frame-shaped printed layer may exist as a level difference. If the pressure-sensitive adhesive layer does not follow the level difference, the pressure-sensitive adhesive layer floats near the level difference, thereby causing light reflection loss. Therefore, the level difference followable|trackability is calculated|required by the said adhesive layer.

In order to solve the above problems, Patent Document 1 is an adhesive layer filling the gap between the protective panel and the display module, and the shear storage modulus (G') at 25 ° C. and 1 Hz is 1.0 × 10 ⁵ Pa or less, Moreover, the pressure-sensitive adhesive layer having a gel fraction of 40% or more is disclosed.

Patent Document 1: Japanese Patent Application Laid-Open No. 2010-97070

In patent document 1, it is going to improve step|step difference followability|trackability by making low the storage modulus at the time of the normal temperature in an adhesive layer. However, when the storage modulus at room temperature is lowered as described above, the storage modulus at high temperature is lowered more than necessary, and a problem occurs under durable conditions. For example, after implementing high-temperature, high-humidity conditions, when returning to normal temperature and normal humidity, the problem that an adhesive layer whitens or a bubble generate|occur|produces in the step|step difference vicinity generate|occur|produces.

On the other hand, although a glass plate is generally used as the said protective panel, a plastic plate may be used by the request|requirement of thin film reduction, weight reduction, etc. in recent years. In a high-temperature environment, gas (outgas) may be generated from this plastic plate. When such a plastic plate is used, air bubbles and floatation and peeling (blister) may arise between a plastic plate and an adhesive layer by said outgas.

The present invention has been made in view of these actual conditions, and an object of the present invention is to provide an active energy ray-curable pressure-sensitive adhesive sheet and a laminate having a pressure-sensitive adhesive layer that is excellent in step difference followability, wet-and-heat whitening resistance, durability, and blister resistance.

In order to achieve the above object, the first present invention is a pressure-sensitive adhesive sheet having an active energy ray-curable pressure-sensitive adhesive layer, with respect to the storage modulus at 23° C. before irradiating the pressure-sensitive adhesive layer with an active energy ray, the pressure-sensitive adhesive layer The ratio of the storage modulus at 23 ° C after irradiating the active energy ray with respect to is 1.1 to 10, the both sides of the pressure-sensitive adhesive layer are sandwiched between two sheets of 1.1 mm thick alkali-free glass, and the active energy ray is irradiated through one glass, After the obtained laminate was stored for 240 hours under moist heat conditions of 85°C and 85%RH, the haze value (%) before the wet heat condition was subtracted from the haze value (%) when taken out under normal temperature and humidity at 23°C and 50%RH It provides an active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the haze value rise after the wet heat condition, which is a value, is less than 5.0 points (Invention 1).

The second present invention is a pressure-sensitive adhesive sheet having an active energy ray-curable pressure-sensitive adhesive layer, wherein the pressure-sensitive adhesive layer is irradiated with active energy rays for the storage modulus at 85° C. before irradiation with active energy rays for the pressure-sensitive adhesive layer. The ratio of the storage modulus at 85 ° C. is 1.1 to 10, and the laminate obtained by sandwiching both surfaces of the pressure-sensitive adhesive layer between two sheets of 1.1 mm thick alkali-free glass and irradiating an active energy ray through one glass is 85 ° C., Haze value increase after moist heat condition, which is the value obtained by subtracting the haze value (%) before the wet heat condition from the haze value (%) when stored under 85%RH moist heat condition for 240 hours and then taken out under 23°C and 50%RH room temperature and humidity It provides an active energy ray-curable adhesive sheet, which is less than 5.0 points (Invention 2).

In the said invention (invention 1, 2), it is preferable that the storage modulus in 23 degreeC of the said adhesive layer before active energy ray irradiation is 0.01-0.2 MPa (invention 3).

In the said invention (invention 1-3), it is preferable that the storage modulus in 23 degreeC of the said adhesive layer after active energy ray irradiation is 0.02-2 MPa (invention 4).

In the said invention (invention 1-4), it is preferable that the storage modulus in 85 degreeC of the said adhesive layer before active energy ray irradiation is 0.01-0.1 MPa (invention 5).

In the said invention (invention 1-5), it is preferable that the storage modulus in 85 degreeC of the said adhesive layer after active energy ray irradiation is 0.02-0.5 MPa (invention 6).

In the said invention (invention 1-6), it is preferable that the thickness of the said adhesive layer is 50-400 micrometers (invention 7).

In the above inventions (Inventions 1 to 7), it is preferable that the active energy ray-curable pressure-sensitive adhesive sheet includes two release sheets, and the pressure-sensitive adhesive layer is sandwiched between the release sheets so as to be in contact with the release surfaces of the two release sheets. do (invention 8).

A third aspect of the present invention is a laminate comprising two hard plates and an adhesive layer sandwiched between the two hard plates, wherein the adhesive layer comprises an adhesive layer of the active energy ray-curable adhesive sheet (inventions 1 to 8). Provided is a laminate characterized in that it is cured by irradiation with active energy rays (Invention 9).

In the said invention (invention 9), it is preferable that at least one of the said hard plate has a level|step difference in the said adhesive layer side surface (invention 10).

In the above invention (Invention 10), it is preferable that the level difference is the level difference depending on the presence or absence of the printed layer (Invention 11).

In the said invention (Inventions 9-11), it is preferable that at least one of the said hard plate contains a polarizing plate (Invention 12).

In the above inventions (Inventions 9 to 12), it is preferable that at least one of the rigid plates includes a plastic plate (Invention 13).

In the above inventions (Inventions 9 to 11), one of the two hard plates is a display module or a part thereof, and the other of the two hard plates is a protective plate having a frame frame-shaped step on the surface on the side of the pressure-sensitive adhesive layer. It is preferable (Invention 14).

In the said invention (Inventions 9-14), it is preferable that the total light transmittance of the said adhesive layer is 80 % or more.

The fourth present invention has a weight average molecular weight of 200,000 to 900,000, and contains 5 to 20% by mass of a monomer having a carboxyl group as a monomer unit constituting the polymer, or 15 to 30% by mass of a monomer having a hydroxyl group ( It contains a meth)acrylic acid ester copolymer (A), an active energy ray-curable component (B), and a crosslinking agent (C), and the content of the active energy ray-curable component (B) is the (meth)acrylic acid ester copolymer ( A) An active energy ray-curable pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer having a thickness of 50 to 400 µm formed by thermal crosslinking of an adhesive composition of 10 to 50 parts by mass with respect to 100 parts by mass is provided.

In the above invention, the pressure-sensitive adhesive layer obtained by thermally crosslinking a pressure-sensitive adhesive composition containing a (meth)acrylic acid ester copolymer having a small weight average molecular weight and a predetermined amount of hydroxyl or carboxyl groups is excellent in step followability and heat-and-moisture whitening resistance, have adequate durability. Moreover, since the said adhesive composition contains many active energy ray-curable components, the said adhesive layer is hardened by irradiation of an active energy ray, and the adhesive layer hardened in this way becomes excellent in durability and blister resistance.

In the said invention, it is preferable that content of the said crosslinking agent (C) in the said adhesive composition is 0.01-5 mass parts with respect to 100 mass parts of said (meth)acrylic acid ester copolymer (A).

The pressure-sensitive adhesive layer of the active energy ray-curable pressure-sensitive adhesive sheet according to the present invention is excellent in followability to steps, and is also excellent in moisture and heat whitening resistance, durability and blister resistance after active energy ray irradiation. In a laminate obtained by using such an active energy ray-curable pressure-sensitive adhesive sheet, even if there is a level difference on the pressure-sensitive adhesive layer side, since the pressure-sensitive adhesive layer follows the level difference, there is no floatation or bubbles near the level difference. Moreover, the adhesive layer after active energy ray irradiation in the said laminated body is excellent also in heat-and-moisture whitening resistance, durability, and blister resistance.

1 is a cross-sectional view of an active energy ray-curable pressure-sensitive adhesive sheet according to an embodiment of the present invention.
2 is a cross-sectional view of a laminate according to one embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described.

[Active energy ray-curable adhesive sheet]

As shown in Fig. 1, an active energy ray-curable pressure-sensitive adhesive sheet 1 according to the present embodiment (which may be simply referred to as "adhesive sheet" in this specification) includes two release sheets 12a and 12b, and It is composed of a pressure-sensitive adhesive layer 11 sandwiched between the two release sheets 12a and 12b so as to be in contact with the release surfaces of the two release sheets 12a and 12b. In the present specification, the release surface of the release sheet refers to the surface having peelability in the release sheet, and includes both the surface subjected to the peeling treatment and the surface showing the peelability even without performing the peeling treatment.

1. Adhesive layer

The pressure-sensitive adhesive layer 11 has a weight average molecular weight of 200,000 to 900,000, and contains 5 to 20% by mass of a monomer having a carboxyl group (carboxyl group-containing monomer) as a monomer unit constituting the polymer, or a monomer having a hydroxyl group (containing a hydroxyl group) A (meth)acrylic acid ester copolymer (A) containing 15 to 30% by mass of a monomer), an active energy ray-curable component (B), and a pressure-sensitive adhesive composition (hereinafter referred to as “adhesive composition P”) containing a crosslinking agent (C) ) is an active energy ray-curable pressure-sensitive adhesive layer formed by thermal crosslinking. In addition, in this specification, (meth)acrylic acid means both acrylic acid and methacrylic acid. The same is true for other similar terms.

The pressure-sensitive adhesive layer 11 in the pressure-sensitive adhesive sheet 1 is formed by thermally crosslinking the pressure-sensitive adhesive composition P, specifically, the (meth)acrylic acid ester copolymer (A) is crosslinked by the crosslinking agent (C). . On the other hand, the active energy ray-curable component (B) is not yet hardened|cured but exists in the adhesive layer 11 in the state mix|blended with the adhesive composition P. This active energy ray-curable component (B) polymerize|polymerizes and hardens when an active energy ray is irradiated with respect to the adhesive layer 11 at the time of use of the adhesive sheet 1 (when bonding a to-be-adhered body).

(1) (meth)acrylic acid ester copolymer (A)

The (meth)acrylic acid ester copolymer (A) is the adhesive main agent in the adhesive composition P. The (meth)acrylic acid ester copolymer (A) contains 5-20 mass % of a carboxyl group-containing monomer as a monomer unit which comprises the polymer, or contains 15-30 mass % of a hydroxyl-containing monomer. When the content of the carboxyl group-containing monomer or the hydroxyl group-containing monomer is in the above range, the crosslinked structure formed by the (meth)acrylic acid ester copolymer (A) and the crosslinking agent (C) becomes good, and the pressure-sensitive adhesive layer 11 is suitable have durability. Moreover, the adhesive layer 11 obtained from the adhesive composition P containing the (meth)acrylic acid ester copolymer (A) whose content of a carboxyl group-containing monomer or a hydroxyl-containing monomer exists in the said range hardening of the adhesive layer 11 After implementing high-temperature, high-humidity conditions (for example, under 85 degreeC, 85%RH conditions for 240 hours), whitening at the time of returning to normal temperature and normal humidity is suppressed, that is, it becomes excellent in moist heat whitening resistance. When the (meth)acrylic acid ester copolymer (A) contains a carboxyl group-containing monomer or a hydroxyl group-containing monomer in the above amount as a monomer unit, a predetermined amount of a carboxyl group or a hydroxyl group remains in the resulting pressure-sensitive adhesive. The carboxyl group and the hydroxyl group are hydrophilic groups, and when such hydrophilic groups exist in a predetermined amount of the pressure-sensitive adhesive, even when the pressure-sensitive adhesive is placed under high-temperature, high-humidity conditions, moisture that has penetrated into the pressure-sensitive adhesive under the high-temperature, high-humidity conditions is easily removed from the pressure-sensitive adhesive when returned to normal temperature and humidity. It is estimated that, as a result, whitening of an adhesive is suppressed.

If the content of the carboxyl group-containing monomer as a monomer unit in the (meth)acrylic acid ester copolymer (A) is less than 5% by mass or the content of the hydroxyl group-containing monomer is less than 15% by mass, the pressure-sensitive adhesive layer 11 is particularly moist and heat whitening resistance this will fall On the other hand, when content of a carboxyl group-containing monomer exceeds 20 mass %, or content of a hydroxyl-containing monomer exceeds 30 mass %, the coatability of the adhesive composition P worsens.

From the above point of view, the (meth)acrylic acid ester copolymer (A) contains 7 to 15% by mass, particularly 8 to 12% by mass of a carboxyl group-containing monomer as a monomer unit constituting the polymer, or 17 to 28% by mass of a hydroxyl group-containing monomer It is preferable to contain in mass %, especially 20-25 mass %.

Examples of the carboxyl group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. Among them, (meth)acrylic acid is preferable, and especially acrylic acid is preferable from the viewpoint of reactivity of the carboxyl group in the obtained (meth)acrylic acid ester polymer (A) with the crosslinking agent (B) and copolymerizability with other monomers. These may be used independently and may be used in combination of 2 or more type.

As a hydroxyl-containing monomer, For example, (meth)acrylic acid 2-hydroxyethyl, (meth)acrylic acid 2-hydroxypropyl, (meth)acrylic acid 3-hydroxypropyl, (meth)acrylic acid 2-hydroxybutyl, (meth)acrylic acid hydroxyalkyl esters, such as (meth)acrylic-acid 3-hydroxybutyl and (meth)acrylic-acid 4-hydroxybutyl, etc. are mentioned. Among them, 2-hydroxyethyl (meth)acrylic acid is preferable from the viewpoint of the reactivity of the hydroxyl group in the obtained (meth)acrylic acid ester polymer (A) with the crosslinking agent (B) and copolymerizability with other monomers. These may be used independently and may be used in combination of 2 or more type.

The (meth)acrylic acid ester copolymer (A) preferably contains (meth)acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group as a monomer unit constituting the polymer, and particularly preferably as a main component. Thereby, the adhesive obtained can express preferable adhesiveness.

Examples of the (meth)acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, (meth)acrylate n-butyl, (meth) Acrylic acid n-pentyl, (meth)acrylic acid n-hexyl, (meth)acrylic acid 2-ethylhexyl, (meth)acrylic acid isooctyl, (meth)acrylic acid n-decyl, (meth)acrylic acid n-dodecyl, (meth)acrylic acid Myristyl, (meth)acrylic acid palmityl, (meth)acrylic acid stearyl, etc. are mentioned. Among them, from the viewpoint of further improving the adhesiveness, (meth)acrylic acid ester having 1 to 8 carbon atoms in the alkyl group is preferable, and methyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylic acid This is particularly preferred. Moreover, these may be used independently and may be used in combination of 2 or more type.

The (meth)acrylic acid ester copolymer (A) preferably contains 50% by mass or more of (meth)acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group as a monomer unit constituting the polymer, and particularly 60% by mass or more It is preferable to contain, and it is more preferable to contain 70 mass % or more. Moreover, it is preferable that the upper limit of content of the C1-C20 (meth)acrylic acid alkyl ester of an alkyl group is the remainder except a carboxyl group containing monomer and a hydroxyl group containing monomer.

The (meth)acrylic acid ester copolymer (A) may contain another monomer as a monomer unit constituting the polymer as desired. As another monomer, in order not to interfere with the action|action of a carboxyl group-containing monomer or a hydroxyl-containing monomer, the monomer which does not contain the functional group which has reactivity is preferable. Examples of such other monomers include (meth)acrylic acid alkoxyalkyl esters such as (meth)acrylic acid methoxyethyl, (meth)acrylic acid ethoxyethyl, and (meth)acrylic acid cyclohexyl (meth) having an aliphatic ring. Non-crosslinkable acrylamide such as acrylic acid ester, acrylamide, and methacrylamide, having a non-crosslinkable tertiary amino group such as (meth)acrylic acid N,N-dimethylaminoethyl, and (meth)acrylic acid N,N-dimethylaminopropyl (meth)acrylic acid ester, vinyl acetate, styrene, etc. are mentioned. These may be used independently and may be used in combination of 2 or more type.

A random copolymer may be sufficient as the polymerization form of a (meth)acrylic acid ester copolymer (A), and a block copolymer may be sufficient as it.

The weight average molecular weights of (meth)acrylic acid ester copolymer (A) are 200,000-900,000, and it is preferable that it is 250,000-700,000. In addition, the weight average molecular weight in this specification is the value of polystyrene conversion measured by the gel permeation chromatography (GPC) method.

Since the weight average molecular weight of the (meth)acrylic acid ester copolymer (A), which is the main component of the pressure-sensitive adhesive composition P, is relatively small as described above, the pressure-sensitive adhesive layer 11 obtained by thermally crosslinking the pressure-sensitive adhesive composition P is excellent in step followability. When the weight average molecular weight of the (meth)acrylic acid ester copolymer (A) exceeds 900,000, the level difference followability is deteriorated. On the other hand, when the weight average molecular weight of the (meth)acrylic acid ester copolymer (A) is less than 200,000, the pressure-sensitive adhesive layer 11 after active energy ray irradiation is inferior in durability. In addition to the above viewpoint, in consideration of step followability and durability, the weight average molecular weight of the (meth)acrylic acid ester copolymer (A) is particularly preferably 300,000 to 500,000, and considering blister resistance, (meth)acrylic acid ester It is especially preferable that the weight average molecular weights of a copolymer (A) are 500,000-700,000.

Moreover, in the adhesive composition P, the (meth)acrylic acid ester copolymer (A) may be used individually by 1 type, and may be used in combination of 2 or more type.

(2) active energy ray-curable component (B)

When the adhesive composition P contains an active energy ray-curable component (B), the adhesive layer 11 formed turns into an active-energy-ray-curable adhesive layer. By containing the active energy ray-curable component (B), this pressure-sensitive adhesive layer 11 is excellent in step followability and durability.

The active energy ray-curable component (B) is not particularly limited as long as it is a component that is cured by irradiation with an active energy ray without interfering with the effects of the present invention, and may be any of a monomer, an oligomer or a polymer, or a mixture thereof. . Among them, a polyfunctional acrylate-based monomer having a molecular weight of less than 1000 excellent in compatibility with the (meth)acrylic acid ester copolymer (A) or the like is preferably exemplified.

Examples of the polyfunctional acrylate-based monomer having a molecular weight of less than 1000 include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and neopentylglycol di(meth)acryl. rate, polyethylene glycol di (meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone bifunctional types such as modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified phosphoric acid di(meth)acrylate, di(acryloxyethyl)isocyanurate, and arylated cyclohexyl di(meth)acrylate; Trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide modified trime trifunctional types such as tyrolpropane tri(meth)acrylate, tris(acryloxyethyl)isocyanurate, and ε-caprolactone-modified tris(2-(meth)acryloxyethyl)isocyanurate; tetrafunctional types such as diglycerol tetra(meth)acrylate and pentaerythritol tetra(meth)acrylate; 5 functional types, such as propionic acid modified dipentaerythritol penta (meth)acrylate; 6 functional types, such as dipentaerythritol hexa(meth)acrylate and caprolactone modified dipentaerythritol hexa(meth)acrylate, etc. are mentioned. These may be used individually by 1 type, and may be used in combination of 2 or more type.

As the active energy ray-curable component (B), an active energy ray-curable acrylate-based oligomer can also be used. The acrylate-based oligomer preferably has a weight average molecular weight of 50,000 or less. Examples of such an acrylate oligomer include polyester acrylate, epoxy acrylate, urethane acrylate, polyether acrylate, polybutadiene acrylate, and silicone acrylate.

Here, the polyester acrylate-based oligomer is, for example, by esterifying the hydroxyl groups of a polyester oligomer having hydroxyl groups at both terminals obtained by condensation of a polyhydric carboxylic acid and a polyhydric alcohol with (meth)acrylic acid, or It can obtain by esterifying the hydroxyl group of the terminal of the oligomer obtained by adding alkylene oxide to main acid with (meth)acrylic acid. The epoxy acrylate-based oligomer can be obtained by, for example, reacting (meth)acrylic acid with an oxirane ring of a bisphenol-type epoxy resin or a novolak-type epoxy resin and esterifying it. Moreover, the epoxy acrylate oligomer of the carboxyl modification type which modified|denatured this epoxy acrylate type oligomer partly with dibasic carboxylic acid anhydride can also be used. The urethane acrylate oligomer can be obtained by, for example, esterifying a polyurethane oligomer obtained by reaction of polyether polyol or polyester polyol with polyisocyanate with (meth)acrylic acid. A polyol acrylate type oligomer can be obtained by esterifying the hydroxyl group of polyether polyol with (meth)acrylic acid.

The weight average molecular weight of the acrylate-based oligomer is preferably 50,000 or less, particularly preferably 500 to 50,000, and more preferably 3,000 to 40,000. These acrylate oligomers may be used individually by 1 type, and may be used in combination of 2 or more type.

Moreover, as an active energy ray-curable component (B), the adduct acrylate type polymer in which the group which has a (meth)acryloyl group was introduce|transduced into the side chain can also be used. Such an adduct acrylate polymer uses a copolymer of (meth)acrylic acid ester and a monomer having a crosslinkable functional group in the molecule, and includes a (meth)acryloyl group and crosslinking in some of the crosslinkable functional groups of the copolymer. It can be obtained by reacting a compound having a group that reacts with a sexual functional group.

The (meth)acrylic acid ester preferably contains (meth)acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylic acid , (meth) butyl acrylate, (meth) acrylate pentyl, (meth) acrylic acid hexyl, (meth) acrylic acid cyclohexyl, (meth) acrylic acid 2-ethylhexyl, (meth) acrylate isooctyl, (meth) acrylic acid decyl, (meth) acrylate ) Acrylic acid dodecyl, (meth)acrylic acid myristyl, (meth)acrylic acid palmityl, (meth)acrylic acid stearyl, etc. are mentioned. These may be used independently and may be used in combination of 2 or more type.

It is preferable that the monomer which has a crosslinkable functional group in the said molecule|numerator contains at least 1 sort(s) selected from a hydroxyl group, a carboxyl group, an amino group, and an amide group as a functional group. As such a monomer, for example, (meth)acrylic acid 2-hydroxyethyl, (meth)acrylic acid 2-hydroxypropyl, (meth)acrylic acid 3-hydroxypropyl, (meth)acrylic acid 2-hydroxybutyl, ( (meth)acrylic acid hydroxyalkyl esters, such as 3-hydroxybutyl (meth)acrylic acid and 4-hydroxybutyl (meth)acrylic acid; acrylamides such as N-methylol methacrylamide; (meth)acrylic acid monoalkylaminoalkyl, such as (meth)acrylic acid monomethylaminoethyl, (meth)acrylic acid monoethylaminoethyl, (meth)acrylic acid monomethylaminopropyl, and (meth)acrylic acid monoethylaminopropyl; and ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These monomers may be used independently and may be used in combination of 2 or more type.

Examples of the compound having a (meth)acryloyl group and a group reactive with a crosslinkable functional group include 2-methacryloyloxyethyl isocyanate, methacrylic acid 2-(0-[1'-methylpropylideneamino] Carboxyamino)ethyl, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate, 2-acryloyloxyethyl isocyanate, 2-acryloyloxyethyl succinate, 2-acryloyloxyethyl hexahydrophthalimide, ω-carboxy-polycaprolactone monoacrylate, phthalic acid monohydroxyethyl acrylate, 2-hydroxy-3- Phenoxypropyl acrylate etc. are mentioned preferably. These compounds may be used independently and may be used in combination of 2 or more type.

It is preferable that the weight average molecular weight of the said adduct acrylate polymer is about 50,000-900,000, and it is especially preferable that it is about 100,000-300,000.

The active energy ray-curable component (B) may be used by selecting one type from among the aforementioned polyfunctional acrylate-based monomers, acrylate-based oligomers and adduct acrylate-based polymers, or may be used in combination of two or more types, It can also be used in combination with other active energy ray-curable components.

Content of the active energy ray-curable component (B) in adhesive composition P needs to be 10-50 mass parts with respect to 100 mass parts of (meth)acrylic acid ester copolymer (A), Preferably it is 15-45 mass parts. and particularly preferably 25 to 40 parts by mass. When the content of the active energy ray-curable component (B) is 10 parts by mass or more, the pressure-sensitive adhesive layer 11 after active energy ray irradiation has an improved cohesive force, and even if outgas is generated from the plastic plate in a high-temperature environment, bubbles or float · The occurrence of peeling is suppressed and the blister resistance is excellent. That is, the blister resistance excellent in the adhesive layer 11 after active energy ray irradiation that content of an active energy ray-curable component (B) is less than 10 mass parts is not acquired. On the other hand, when the content of the active energy ray-curable component (B) exceeds 50 parts by mass, the adhesive force of the pressure-sensitive adhesive layer 11 before irradiation with active energy rays becomes too high, and the release sheets 12a and 12b are gently peeled from the pressure-sensitive adhesive layer 11 . It becomes difficult to carry out, and there is a fear that the pressure-sensitive adhesive layer 11 may be destroyed when the release sheets 12a and 12b are peeled off. Moreover, the adhesive layer 11 after active energy ray irradiation can hold|maintain the bonding state of hard boards firmly by having the adhesive force (thing with respect to a glass substrate) about 10 N/25 mm or more.

(3) crosslinking agent (C)

The pressure-sensitive adhesive composition P contains a crosslinking agent (C), thereby crosslinking the (meth)acrylic acid ester copolymer (A) to form a three-dimensional network structure, thereby improving the cohesive force of the obtained pressure-sensitive adhesive. Moreover, durability can also be provided to the adhesive after active energy ray irradiation.

As the crosslinking agent (C), any one that reacts with the reactive group (carboxyl group or hydroxyl group) of the (meth)acrylic acid ester copolymer (A) is sufficient, for example, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an amine type crosslinking agent, a melamine type crosslinking agent , an aziridine-based crosslinking agent, a hydrazine-based crosslinking agent, an aldehyde-based crosslinking agent, an oxazoline-based crosslinking agent, a metal alkoxide-based crosslinking agent, a metal chelate-based crosslinking agent, a metal salt-based crosslinking agent, and an ammonium salt-based crosslinking agent. A crosslinking agent (C) can be used individually by 1 type or in combination of 2 or more type.

When the (meth)acrylic acid ester copolymer (A) contains a carboxyl group-containing monomer, at least one selected from an epoxy-based crosslinking agent and an isocyanate-based crosslinking agent having excellent reactivity with a carboxyl group is preferably used as the crosslinking agent (C). , it is particularly preferable to use an epoxy-based crosslinking agent. When (meth)acrylic acid ester copolymer (A) contains a hydroxyl-containing monomer, it is preferable to use the isocyanate type crosslinking agent excellent in reactivity with a hydroxyl group.

As the epoxy-based crosslinking agent, for example, 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-m-xylyl Rendiamine, ethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, diglycidylamine, etc. are mentioned.

The isocyanate-based crosslinking agent contains at least a polyisocyanate compound. As a polyisocyanate compound, For example, aromatic polyisocyanate, such as tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, aliphatic polyisocyanate, such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diisocyanate Alicyclic polyisocyanates such as phenylmethane diisocyanate, and their biuret forms, isocyanurates, and low molecular weight active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, and castor oil The adduct body etc. which are reactants are mentioned.

It is preferable that content of the crosslinking agent (C) in the adhesive composition P is 0.01-5 mass parts with respect to 100 mass parts of (meth)acrylic acid ester copolymer (A), It is especially preferable that it is 0.05-1 mass part. When content of a crosslinking agent (C) is 0.01 mass part or more, the durable improvement effect can be provided to the adhesive after active energy ray irradiation. When content of a crosslinking agent (C) exceeds 5 mass parts, the grade of crosslinking becomes excessive, and there exists a possibility that the level|step difference followable|trackability of the adhesive obtained may fall. In addition, the carboxyl group or hydroxyl group of the (meth)acrylic acid ester copolymer (A) reacts with the crosslinking agent (C) in a large amount, the amount of the carboxyl group or hydroxyl group remaining in the pressure-sensitive adhesive decreases, and the above-mentioned moisture heat whitening resistance is likely to decrease there is From the viewpoint of making durability most preferable in addition to the above viewpoint, the content of the crosslinking agent (C) is preferably 0.05 to 0.4 parts by mass, and from the viewpoint of making the blister resistance most preferable, the content of the crosslinking agent (C) is 0.3 to 1 It is preferable that it is a mass part.

(4) photoinitiator (D)

When using an ultraviolet-ray as an active energy ray irradiated with respect to the adhesive layer 11, it is preferable that the adhesive composition P contains a photoinitiator (D) further. Thus, by containing a photoinitiator (D), an active energy ray-curable component (B) can be hardened efficiently, and polymerization hardening time and the irradiation amount of an active energy ray can be reduced.

Examples of the photopolymerization initiator (D) include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylamino Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydro Roxy cyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 4-(2-hydroxyethoxy)phenyl-2-(hydroxyl -2-propyl) ketone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone , 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal , acetophenone dimethyl ketal, p-dimethylamino benzoic acid ester, oligo [2-hydroxy-2-methyl-1 [4- (1-methylvinyl) phenyl] propanone], 2,4,6-trimethylbenzoyl-di phenyl-phosphine oxide etc. are mentioned. These may be used independently and may be used in combination of 2 or more type.

It is preferable to use a photoinitiator (D) in the quantity of 2-15 mass parts, especially 4-12 mass parts with respect to 100 mass parts of active energy ray-curable components (B).

(5) Various additives

To the pressure-sensitive adhesive composition P, if desired, various additives commonly used in acrylic pressure-sensitive adhesives, such as silane coupling agents, antistatic agents, tackifiers, antioxidants, ultraviolet absorbers, light stabilizers, softeners, fillers, refractive index modifiers, etc. are added. can do

It is preferable that a silane coupling agent is added as an additive to the adhesive composition P from a viewpoint of especially improving durability. As a silane coupling agent, it is an organosilicon compound which has at least one alkoxy silyl group in a molecule|numerator, Compatibility with the (meth)acrylic acid ester copolymer (A) is preferable. Moreover, when the adhesive sheet 1 is an optical use, the silane coupling agent which has light transmittance is suitable.

Examples of the silane coupling agent include polymerizable unsaturated group-containing silicon compounds such as vinyltrimethoxysilane, vinyltriethoxysilane, and methacryloxypropyl trimethoxysilane, 3-glycidoxypropyl trimethoxy Silicon compound having an epoxy structure such as silane, 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, 3-mercaptopropyl trimethoxysilane, 3-mercaptopropyl triethoxysilane, 3-mer Mercapto group-containing silicon compounds such as captopropyl dimethoxymethylsilane, 3-aminopropyl trimethoxysilane, N-(2-aminoethyl)-3-aminopropyl trimethoxysilane, N-(2-aminoethyl)- Amino group-containing silicon compounds such as 3-aminopropyl methyldimethoxysilane, 3-chloropropyl trimethoxysilane, 3-isocyanatepropyl triethoxysilane, or at least one of these, methyltriethoxysilane, ethyltriethoxy Condensates with alkyl-group containing silicon compounds, such as silane, methyl trimethoxysilane, and ethyl trimethoxysilane, etc. are mentioned. These may be used individually by 1 type, and may be used in combination of 2 or more type.

It is preferable that it is 0.01-1.0 mass part with respect to 100 mass parts of (meth)acrylic acid ester copolymer (A), and, as for the addition amount of a silane coupling agent, it is preferable that it is especially 0.05-0.5 mass part.

(6) Preparation of adhesive composition

The adhesive composition P prepares the (meth)acrylic acid ester copolymer (A), and mixes the obtained (meth)acrylic acid ester copolymer (A), the active energy ray-curable component (B), and the crosslinking agent (C) If desired, it can manufacture by adding a photoinitiator (D) and/or an additive.

A (meth)acrylic acid ester copolymer (A) can be manufactured by superposing|polymerizing the mixture of the monomer which comprises a polymer by a normal radical polymerization method. Polymerization of (meth)acrylic acid ester copolymer (A) can be performed by the solution polymerization method etc. using a polymerization initiator as needed. As a polymerization solvent, ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone etc. are mentioned, for example, You may use 2 or more types together.

As a polymerization initiator, an azo type compound, an organic peroxide, etc. are mentioned, You may use 2 or more types together. As the azo compound, for example, 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), 1,1'-azobis(cyclohexane 1- carbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(2,4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2' -Azobis(2-methylpropionate), 4,4'-azobis(4-cyanovaleric acid), 2,2'-azobis(2-hydroxymethylpropionitrile), 2,2' -Azobis[2-(2-imidazolin-2-yl)propane] etc. are mentioned.

Examples of the organic peroxide include benzoyl peroxide, t-butylperbenzoate, cumene hydroperoxide, diisopropylperoxydicarbonate, di-n-propylperoxydicarbonate, di(2-ethoxyethyl)peroxydi carbonate, t-butyl peroxyneodecanoate, t-butyl peroxybivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, diacetyl peroxide, and the like.

Further, in the polymerization step, the weight average molecular weight of the obtained polymer can be adjusted by adding a chain transfer agent such as 2-mercaptoethanol.

After the (meth)acrylic acid ester copolymer (A) is obtained, in a solution of the (meth)acrylic acid ester copolymer (A), an active energy ray-curable component (B), a crosslinking agent (C), and optionally a photopolymerization initiator (D) ), an additive is added, and the adhesive composition P is obtained by fully mixing.

(7) Formation of the pressure-sensitive adhesive layer

The pressure-sensitive adhesive layer 11 is formed by thermally crosslinking the pressure-sensitive adhesive composition P. That is, crosslinking of the adhesive composition P is performed by heat treatment. In addition, this heat treatment can also serve as a drying process after application|coating of the adhesive composition P.

It is preferable that it is 50-150 degreeC, and, as for the heating temperature of heat processing, it is especially preferable that it is 70-120 degreeC. Moreover, it is preferable that they are 10 second - 10 minutes, and, as for heating time, it is especially preferable that they are 50 second - 2 minutes. After the heat treatment, if necessary, a curing period of about 1 to 2 weeks may be set at normal temperature (eg, 23°C, 50%RH). A pressure-sensitive adhesive layer is formed after the lapse of the curing period when this curing period is required, and after the end of the heat treatment when the curing period is unnecessary.

By the above heat treatment (and curing), the (meth)acrylic acid ester copolymer (A) is favorably crosslinked via the crosslinking agent (C).

The thickness (value measured based on JIS K7130) of the adhesive layer 11 formed is 50-400 micrometers, Preferably it is 70-300 micrometers, Especially preferably, it is 90-250 micrometers. In addition, the adhesive layer 11 may be formed in a single layer, and may be formed by laminating|stacking multiple layers.

When the thickness of the adhesive layer 11 is less than 50 micrometers, sufficient step|step difference followability|trackability is not acquired, and when the thickness of the adhesive layer 11 exceeds 400 micrometers, workability is inferior.

2. Release sheet

The release sheets 12a and 12b include, for example, a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, and a polyethylene film. Naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate film, ionomer resin film, ethylene/(meth)acrylic acid copolymer film, ethylene/(meth)acrylic acid ester copolymer film, polystyrene film, A polycarbonate film, a polyimide film, a fluororesin film, etc. are used. Moreover, these crosslinked films are also used. Moreover, these laminated|multilayer films may be sufficient.

It is preferable that the peeling surface (particularly the side in contact with the pressure-sensitive adhesive layer 11) of the release sheets 12a and 12b is subjected to a peeling treatment. Examples of the release agent used in the peeling treatment include alkyd-based, silicone-based, fluorine-based, unsaturated polyester-based, polyolefin-based, and wax-based release agents. In addition, it is preferable that one of the release sheets 12a and 12b is a medium release type release sheet having a large peeling force, and the other release sheet is a light release type release sheet having a small peeling force.

Although there is no restriction|limiting in particular about the thickness of the release sheets 12a, 12b, Usually, it is about 20-150 micrometers.

3. Manufacture of adhesive sheet

As one production example of the pressure-sensitive adhesive sheet 1, a coating solution of the pressure-sensitive adhesive composition P is applied to the release surface of one release sheet 12a (or 12b), and the pressure-sensitive adhesive composition P is thermally crosslinked by heat treatment. After the application layer is formed, the release surface of the other release sheet 12b (or 12a) is superimposed on the application layer. When a curing period is required, by providing a curing period, when a curing period is unnecessary, the said application layer becomes the adhesive layer 11 as it is. Thereby, the said adhesive sheet 1 is obtained. In addition, irradiation with an active energy ray is not performed at this stage.

As another manufacturing example of the pressure-sensitive adhesive sheet 1, a coating solution of the pressure-sensitive adhesive composition P is applied to the release surface of one release sheet 12a, and heat treatment is performed to thermally crosslink the pressure-sensitive adhesive composition P to form an application layer. Thus, the release sheet 12a with an application layer is obtained. Further, on the release surface of the other release sheet 12b, the coating liquid of the adhesive composition P is applied, heat treatment is performed to heat crosslink the adhesive composition P to form an application layer, and the release sheet 12b with an application layer is applied. ) to get And the release sheet 12a with an application layer and the release sheet 12b with an application layer are bonded together so that both application layers may mutually contact. When a curing period is required, by providing a curing period, when a curing period is unnecessary, the said laminated|stacked application layer becomes the adhesive layer 11 as it is. Thereby, the said adhesive sheet 1 is obtained. According to this manufacturing example, even when the adhesive layer 11 is thick, it becomes possible to manufacture stably.

As a method of applying the coating liquid of the adhesive composition P, for example, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, or the like can be used.

4. Physical properties

Ratio of the storage elastic modulus at 23 degreeC after irradiating an active energy ray with respect to the adhesive layer 11 with respect to the storage modulus at 23 degreeC before irradiating an active energy ray with respect to the adhesive layer 11 (after active energy ray irradiation) It is preferable that it is 1.1-10, and, as for storage elastic modulus / storage elastic modulus before active energy ray irradiation), it is especially preferable that it is 1.2-7. In addition, let the storage modulus in this specification be the value measured by the torsional shearing method at the measurement frequency of 1 Hz based on JIS　K7244-6.

As described above, since the storage modulus of elasticity at 23° C. of the pressure-sensitive adhesive layer 11 is increased after irradiation with active energy rays (after curing), the cured pressure-sensitive adhesive layer 11 is excellent in both durability and level difference followability. Further, in consideration of blister resistance in addition to the above-mentioned viewpoint, it is particularly preferable that the ratio of the storage modulus is 3-7.

Moreover, ratio of the storage modulus in 85 degreeC after irradiating an active energy ray with respect to the adhesive layer 11 with respect to the storage modulus in 85 degreeC before irradiating an active energy ray with respect to the adhesive layer 11 (active energy ray) It is preferable that it is 1.1-10, and, as for the storage elastic modulus after irradiation/storage elastic modulus before active energy ray irradiation), it is especially preferable that it is 1.3-7. Further, in consideration of blister resistance in addition to the above viewpoint, it is particularly preferable that the ratio of the storage modulus is 3-7.

As described above, after the active energy ray irradiation (after curing), the storage modulus of elasticity at 85°C of the pressure-sensitive adhesive layer 11 increases, whereby the cured pressure-sensitive adhesive layer 11 has excellent durability even under high temperature.

When ratio of the said storage modulus in 23 degreeC or 85 degreeC is less than 1.1, the above durability improvement effect may not be acquired. On the other hand, when ratio of the storage modulus in 23 degreeC or 85 degreeC exceeds 10, the adhesive force of the hardened|cured adhesive layer 11 may fall and there exists a possibility that sufficient durability may not be acquired.

It is preferable that the storage modulus in 23 degreeC of the adhesive layer 11 before active energy ray irradiation is 0.01-0.2 MPa, It is especially preferable that it is 0.04-0.15 MPa, It is more preferable that it is 0.07-0.1 MPa. Moreover, it is preferable that the storage modulus in 85 degreeC of the adhesive layer 11 before active energy ray irradiation is 0.01-0.1 MPa, It is especially preferable that it is 0.01-0.06 MPa, It is more preferable that it is 0.02-0.04 MPa . The pressure-sensitive adhesive layer 11 before active energy ray irradiation has the storage modulus as described above, and thus is excellent in followability to steps.

It is preferable that the storage modulus in 23 degreeC of the adhesive layer 11 after active energy ray irradiation is 0.02-2 MPa, It is especially preferable that it is 0.05-1 MPa, It is more preferable that it is 0.1-0.6 MPa. Moreover, it is preferable that the storage modulus at 85 degreeC of the adhesive layer 11 after active energy ray irradiation is 0.02-0.5 MPa, It is especially preferable that it is 0.02-0.2 MPa, It is more preferable that it is 0.03-0.1 MPa. . The pressure-sensitive adhesive layer 11 after active energy ray irradiation has the storage modulus as described above, and thus is excellent in durability and blister resistance.

In the above-described pressure-sensitive adhesive sheet 1, since the pressure-sensitive adhesive layer 11 before irradiation with active energy rays has excellent level difference followability, even when there is a level difference in the adherend, there is a good gap or bubble between the level difference and the pressure-sensitive adhesive layer 11. It does not occur, and the pressure-sensitive adhesive layer 11 can fill the step. Moreover, by hardening|curing the adhesive layer 11 by irradiation of an active energy ray, it becomes excellent in moist-and-heat whitening resistance, durability, and blister resistance.

It is preferable to use the adhesive layer 11 of the adhesive sheet 1 which concerns on this embodiment, for bonding two hard boards together so that it may mention later.

[Laminate]

As shown in FIG. 2, the laminated body 2 by this embodiment is located between the 1st hard board 21, the 2nd hard board 22, and the 1st hard board 21 ) and the pressure-sensitive adhesive layer 11 sandwiched between the second hard plate 22 . Moreover, in the laminated body 2 which concerns on this embodiment, the 1st hard plate 21 has a level|step difference in the surface on the side of the adhesive layer 11, Specifically, the level|step difference by the presence or absence of the printing layer 3 has a

The first hard plate 21 and the second hard plate 22 are not particularly limited as long as the pressure-sensitive adhesive layer 11 can be attached thereto. Moreover, the same material may be sufficient as the 1st hard plate 21 and the 2nd hard plate 22, and different materials may be sufficient as them.

As the first hard plate 21 and the second hard plate 22, for example, in addition to a glass plate, a plastic plate, a metal plate, a semiconductor plate, and the like, laminates thereof, or a display module, a solar cell module, etc. A plate-shaped hard product, etc. are mentioned. Since the adhesive layer 11 in this embodiment is excellent in blister resistance, it is preferable that at least one of the 1st hard plate 21 and the 2nd hard plate 22 contains a plastic plate.

The glass plate is not particularly limited, and for example, chemically tempered glass, alkali-free glass, quartz glass, soda lime glass, barium strontium-containing glass, aluminosilicate glass, lead glass, borosilicate glass, barium borosilicate glass, etc. can be heard Although the thickness of a glass plate is not specifically limited, Usually, it is 0.1-5 mm, Preferably it is 0.2-2 mm.

It does not specifically limit as said plastic plate, For example, an acrylic plate, a polycarbonate plate, etc. are mentioned. Although the thickness of a plastic plate is not specifically limited, Usually, it is 0.2-5 mm, Preferably it is 0.4-3 mm.

In addition, various functional layers (a transparent conductive film, a metal layer, a silica layer, a hard coating layer, an anti-glare layer, etc.) may be provided on one side or both surfaces of the said glass plate or a plastic plate, and a metal wiring may be formed, and optical The members may be laminated.

Examples of the optical member include a polarizing plate (polarizing film), a polarizer, a retardation plate (retardation film), a viewing angle compensation film, a brightness improving film, a contrast improving film, a liquid crystal polymer film, a diffusion film, a hard coat film, a transflective film A reflective film etc. are mentioned.

Moreover, as said display module, a liquid crystal (LCD) module, a light emitting diode (LED) module, an organic electroluminescent (organic EL) module, electronic paper etc. are mentioned, for example. Moreover, normally, the above-mentioned glass plate, a plastic plate, an optical member, etc. are laminated|stacked on these display module. For example, a polarizing plate is laminated|stacked on an LCD module, and the polarizing plate forms one surface of an LCD module.

In the laminate 2 according to the present embodiment, it is preferable that at least one of the first hard plate 21 and the second hard plate 22 has a polarizing plate. Moreover, the 2nd hard plate 22 in the laminated body 2 by this embodiment is a display body module or its part (for example, optical members, such as a polarizing plate), The 1st hard plate 21 It is preferable that it is a protective plate which consists of a silver plastic plate etc. In this case, it is common that the printing layer 3 is formed in the adhesive layer 11 side of the 1st hard board 21 in the shape of a frame frame.

The material constituting the printed layer 3 is not particularly limited, and a known material for printing is used. It is preferable that the thickness of the printed layer 3, ie, the height of a step is 3-45 micrometers, it is more preferable that it is 5-35 micrometers, It is especially preferable that it is 7-25 micrometers, It is still more preferable that it is 7-15 micrometers. .

In addition, the thickness (height of the step) of the printed layer 3 is preferably 3 to 30% of the thickness of the pressure-sensitive adhesive layer 11, particularly preferably 3.2 to 20%, and more preferably 3.5 to 15%. do. As a result, the pressure-sensitive adhesive layer 11 reliably follows the level difference due to the printed layer 3, so that floating, bubbles, or the like do not occur in the vicinity of the level difference.

The adhesive layer 11 of the laminated body 2 by this embodiment is what hardened the adhesive layer 11 in the adhesive sheet 1 mentioned above by irradiation of an active energy ray. Here, an active energy ray means what has an energy proton in an electromagnetic wave or a charged particle beam, Specifically, an ultraviolet-ray, an electron beam, etc. are mentioned. Among active energy rays, an easy-to-handle ultraviolet ray is particularly preferable.

Irradiation of ultraviolet rays can be performed by a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, or the like, and the irradiation amount of ultraviolet rays is preferably about ^{50 to 1000 mW/cm 2 .} In addition, the amount of light is 50 ~ 10000 mJ / cm ² is not preferred, and more preferred 80 to a 5000 mJ / cm ² and is, particularly preferably 200 to 2000 mJ / cm ^2. On the other hand, irradiation of an electron beam can be performed with an electron beam accelerator etc., The irradiation amount of an electron beam is about 10-1000 krad, and is preferable.

When an active energy ray is irradiated with respect to the adhesive layer 11 in the adhesive sheet 1, an active energy ray-curable component (B) polymerizes and hardens. The adhesive layer 11 hardened|cured by irradiation of an active energy ray becomes excellent in durability, heat-and-moisture whitening resistance, and blister resistance.

In order to manufacture the laminate 2, as an example, first, the release sheet 12a (or 12b) on one side of the pressure-sensitive adhesive sheet 1 is peeled off, and the exposed pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 and the product The first hard plate 21 (or the second hard plate 22) is bonded together. Next, the other release sheet 12b (or 12a) is peeled off from the pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1, and the exposed pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 and the second hard The board 22 (or the 1st hard board 21) is pasted together.

When bonding the pressure-sensitive adhesive layer 11 and the first hard plate 21 to each other in the above step, the pressure-sensitive adhesive layer 11 has excellent level difference followability, and therefore between the level difference due to the printed layer 3 and the pressure-sensitive adhesive layer 11 . The gap is not easily generated, and the pressure-sensitive adhesive layer 11 can fill the step.

Then, an active energy ray is irradiated with respect to the adhesive layer 11 from either side of the 1st hard plate 21 or the 2nd hard plate 22, and the adhesive layer 11 is hardened. At this time, the hard plate on the side irradiated with an active energy ray needs to be active energy ray permeable.

In the above-described laminate 2 , since the pressure-sensitive adhesive layer 11 before irradiation with active energy ray is excellent in followability to steps, voids or bubbles do not easily form between the level difference due to the printed layer 3 and the pressure-sensitive adhesive layer 11 . Moreover, whitening at the time of returning to normal temperature is suppressed, and the adhesive layer 11 hardened|cured by irradiation of an active energy ray is excellent in heat-and-moisture whitening resistance, after implementing high-temperature, high-humidity conditions. Moreover, even when the pressure-sensitive adhesive layer 11 irradiated with active energy rays is performed under high-temperature, high-humidity conditions, the generation of bubbles in the vicinity of the level difference is prevented, and thus, it is excellent in durability. Further, when at least one of the first hard plate 21 and the second hard plate 22 includes a plastic plate, even if outgas is generated from the plastic plate under a high temperature condition, the active energy ray is irradiated. Since the adhesive layer 11 is excellent in blister resistance, generation|occurrence|production of a bubble or floating/peeling is suppressed.

About the outstanding moist-and-heat whitening resistance of the adhesive layer 11 hardened|cured by irradiation of an active energy ray, it can evaluate as follows. For example, lamination|stacking by irradiating the active energy ray of the above-mentioned illuminance and light quantity from at least one side over the alkali-free glass by pinching|interposing both surfaces of the adhesive layer 11 in the alkali-free glass of thickness 1.1mm of 2 sheets, and get a body The laminate is stored for 240 hours at 85°C and 85%RH (wet heat condition), and then taken out at 23°C and 50%RH at normal temperature and humidity. At this time, it is confirmed that the degree of whitening of the pressure-sensitive adhesive layer 11 is small.

The degree of said whitening can also be evaluated quantitatively by a haze value. Specifically, the value obtained by subtracting the haze value (%) before the wet heat condition from the haze value (%) after the wet heat condition in the laminate (the value measured according to JIS K7136:2000. The same applies below) (the haze value after the wet heat condition) rise) can be evaluated. It is preferable that it is less than 5.0 points, and, as for the haze value rise after a wet heat condition, it is especially preferable that it is less than 1.0 point. Moreover, in the said evaluation, it is preferable to use the thing of about 0% of haze value as the said alkali free glass. Moreover, it is preferable that the haze value of the adhesive layer after the said wet heat condition is 1.0 % or less, It is especially preferable that it is 0.9 % or less, It is still more preferable that it is 0.8 % or less.

In addition, the pressure-sensitive adhesive layer 11 has a total light transmittance (value measured according to JIS K7361-1: 1997) of preferably 80% or more, particularly preferably 90% or more, and more preferably 99% or more. . When the total light transmittance is 80% or more, transparency is high and it is suitable as an optical use. Moreover, the total light transmittance of the adhesive layer 11 hardly changes before and behind active energy ray irradiation normally.

The embodiments described above are described in order to facilitate understanding of the present invention, and are not described in order to limit the present invention. Accordingly, each element disclosed in the above embodiments is intended to include all design changes and equivalents falling within the technical scope of the present invention.

For example, either one of the release sheets 12a and 12b in the pressure-sensitive adhesive sheet 1 may be omitted. Moreover, the 1st hard plate 21 may have a level difference other than the printed layer 3, and may not have a level difference. Moreover, not only the 1st hard board 21 but the 2nd hard board 22 may also have a level|step difference in the adhesive layer 11 side.

Example

Hereinafter, the present invention will be described in more detail by way of examples and the like, but the scope of the present invention is not limited to these examples and the like.

[Example 1]

1. Preparation of (meth)acrylic acid ester copolymer

60 mass parts of 2-ethylhexyl acrylate, 20 mass parts of methyl methacrylate, and 20 mass parts of acrylic acid 2-hydroxyethyl were copolymerized, and the (meth)acrylic acid ester copolymer (A) was manufactured. When the molecular weight of this (meth)acrylic acid ester copolymer (A) was measured by the method mentioned later, it was 600,000 weight average molecular weights.

2. Preparation of the adhesive composition

100 parts by mass of the (meth)acrylic acid ester copolymer (A) obtained in the step (1) (solid content conversion; the same applies below), and polyethylene glycol diacrylate as an active energy ray-curable component (B) (manufactured by Shin-Nakamura Chemical Co., Ltd.) , product name "NK ester A-400") 25 parts by mass, trimethylolpropane-modified tolylene diisocyanate (Nippon Polyurethane, product name "Colonate L") as an isocyanate-based crosslinking agent (C) 0.23 parts by mass; 0.2 parts by mass of 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical, product name "KBM-403") as a silane coupling agent, and 1-hydroxycyclohexylphenyl ketone (manufactured by BASF) as a photoinitiator (D) , product name "Igacure 184") 0.5 mass parts was mixed, stirred sufficiently, and diluted with methyl ethyl ketone to obtain a coating solution of the adhesive composition having a solid content concentration of 33 mass%.

Here, the formulation of the adhesive composition is shown in Table 1. In addition, details, such as abbreviation of Table 1, are as follows.

[(meth)acrylic acid ester copolymer]

2EHA: 2-ethylhexyl acrylate

BA: n-butyl acrylate

MMA: methyl methacrylate

HEA: 2-hydroxyethyl acrylate

AA: acrylic acid

[Active energy ray-curable component]

A400: polyethylene glycol diacrylate (manufactured by Shin-Nakamura Chemical, product name "NK Ester A-400")

A9300-1CL: ε-caprolactone-modified tris(2-acryloxyethyl)isocyanurate (manufactured by Shin-Nakamura Chemical, product name "A-930-1CL")

[crosslinking agent]

TDI: Trimethylolpropane-modified tolylene diisocyanate (manufactured by Nippon Polyurethane, product name "Colonate L")

Epoxy: 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane (manufactured by Mitsubishi Chemical Corporation, product name "TETRAD-C")

3. Manufacture of adhesive sheet

The coating solution of the obtained pressure-sensitive adhesive composition was applied to the peeling-treated side of a medium-peelable release sheet (manufactured by Lintec, product name “SP-PET752150”) in which one side of a polyethylene terephthalate film was peeled off with a silicone-based release agent, and the thickness after drying was 100 μm. After apply|coating with a knife coater as much as possible, it heat-processed at 100 degreeC for 4 minutes, and the application layer was formed. Similarly, the coating solution of the obtained pressure-sensitive adhesive composition was applied to the release treatment side of a light-peelable release sheet (manufactured by Lintec, product name “SP-PET382120”) in which one side of a polyethylene terephthalate film was peeled off with a silicone-based release agent, the thickness after drying was After apply|coating with a knife coater so that it might become 100 micrometers, it heat-processed at 100 degreeC for 4 minutes, and the application layer was formed.

Next, the medium release type release sheet with an application layer obtained above and the light release type release sheet with an application layer obtained above were bonded so that both application layers were in contact with each other, and cured for 7 days under the conditions of 23°C and 50%RH. By doing so, a pressure-sensitive adhesive sheet having the structure of a medium release type release sheet/adhesive layer (thickness: 200 µm)/light release type release sheet was produced. In addition, the thickness of an adhesive layer is the value measured using the static pressure thickness measuring machine (the Techrock company make, product name "PG-02") based on JIS K7130.

[Examples 2 to 4, Comparative Examples 1 to 3]

The ratio of each monomer constituting the (meth)acrylic acid ester copolymer (A), the weight average molecular weight of the (meth)acrylic acid ester copolymer (A), the type and blending amount of the active energy ray-curable component (B), the crosslinking agent (C) A pressure-sensitive adhesive sheet was prepared in the same manner as in Example 1 except for changing the type and amount of the photopolymerization initiator (D), the amount of the silane coupling agent, and the thickness of the pressure-sensitive adhesive layer as shown in Table 1.

Here, the aforementioned weight average molecular weight (Mw) is a weight average molecular weight in terms of polystyrene measured using gel permeation chromatography (GPC) under the following conditions (measured by GPC).

<Measurement conditions>

・GPC measuring device: Tosoh Corporation, HLC-8020

・GPC column (pass through in the following order): Tosoh Corporation

TSK guard column HXL-H

TSK gel GMHXL (×2)

TSK gel G2000HXL

·Measurement solvent: tetrahydrofuran

·Measured temperature: 40℃

[Test Example 1] (Measurement of storage modulus)

The light-peelable release sheet and the medium-peelable release sheet were peeled off from the pressure-sensitive adhesive sheets obtained in Examples or Comparative Examples, and a plurality of pressure-sensitive adhesive layers were laminated to a thickness of 0.6 mm. From the obtained laminate of the pressure-sensitive adhesive layer, a cylindrical body (height 0.6 mm) having a diameter of 8 mm was punched out, and this was used as a sample (sample before ultraviolet irradiation).

About the said sample, based on JIS K7244-6, the storage modulus (MPa) of the storage elastic modulus (MPa) was measured by the torsional shearing method using the viscoelasticity measuring apparatus (made by Physica, MCR300) under the following conditions.

Measuring frequency: 1Hz

Measuring temperature: 23℃, 85℃

In addition, for the same sample as above, by irradiating ultraviolet rays under the following conditions with an ultraviolet irradiator (manufactured by EyeGraphix, product name "Eygrantage ECS-401 GX type") to cure the pressure-sensitive adhesive layer, the sample after ultraviolet irradiation got it About the obtained sample after ultraviolet irradiation, it carried out similarly to the sample before ultraviolet irradiation, and measured the storage modulus (MPa).

[Ultraviolet irradiation conditions]

·Light source: high pressure mercury lamp

·Light intensity: 1000mJ/cm ²

· Illuminance: 200mW/cm ²

From the above measurement results, the ratio of the storage modulus after UV irradiation to the storage modulus before UV irradiation at 23° C. and 85° C. (storage modulus after UV irradiation/storage modulus before UV irradiation) was calculated. Table 2 shows their measurement results and calculation results.

[Test Example 2] (Processability evaluation)

The light-peelable release sheet was peeled from the pressure-sensitive adhesive sheet obtained in Examples or Comparative Examples, and the peeling state of the light-peelable release sheet at this time was evaluated as workability. When the light-peelable release sheet was able to peel gently from the pressure-sensitive adhesive layer, the workability was evaluated as good (○), and that in which the pressure-sensitive adhesive layer was destroyed along with the peeling of the light-peelable release sheet was evaluated as poor workability (x). A result is shown in Table 2.

[Test Example 3] (Evaluation of moisture and heat whitening resistance)

A laminate was obtained by sandwiching the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained in Examples or Comparative Examples on two sheets of alkali-free glass having a thickness of 1.1 mm, and irradiating ultraviolet light through one glass under the ultraviolet irradiation conditions of Test Example 1. About the laminate, the haze value (%) was measured based on JIS K7136:2000 using the haze meter (The Nippon Denshoku-Kyo company make, product name "NDH2000").

Next, the laminate was stored for 240 hours under moist heat conditions of 85°C and 85% RH. Then, return to normal temperature and humidity of 23 degreeC, 50%RH, and using the haze meter (made by Nippon Denshoku Kogyo, product name "NDH2000") about the laminated body, based on JIS K7136:2000, the haze value (%) ) was measured. Moreover, the haze value was measured within 30 minutes after returning a laminated body to normal temperature and normal humidity.

Based on the above result, the haze value before wet heat conditions was subtracted from the haze value after wet heat conditions, and the haze value rise (point) after wet heat conditions was computed. Those having a haze value rise of less than 1.0 point after moist heat conditions are good in moist heat and whitening resistance (○), and those having a haze value rise of 1.0 or more and less than 5.0 points after wet heat conditions are within wet heat and whitening resistance aptitude values (Δ), and haze after wet heat conditions A value increase evaluated 5.0 points or more of thing as moisture-and-heat whitening-resistance defect (x). A result is shown in Table 2.

[Test Example 4] (Step followability/durability test)

(a) Preparation of samples for evaluation

UV-curable ink (manufactured by Teikoku Ink, product name "POS-911 Sumi") is applied to the surface of a glass plate (NSG Flashzone, product name "Corning Glass Eagle XG", length 90mm x width 50mm x thickness 0.5mm) Screen printing was carried out in a frame frame shape (external form: 90 mm long x 50 mm wide, 5 mm wide) so that it might become 8 micrometers and 15 micrometers. Then, by irradiating UV rays (80 W/cm ² , metal halide lamp 2 lamps, lamp height 15 cm, belt speed 10-15 m/min), the printed UV curable ink is cured, and the step difference ( Step heights: 8 µm and 15 µm) were prepared.

The pressure-sensitive adhesive sheet obtained in Examples or Comparative Examples was cut into a shape of 90 mm in length × 50 mm in width, and the light-peelable release sheet was removed to expose the pressure-sensitive adhesive layer. Then, using a laminator (manufactured by Fujipla Corporation, product name "LPD3214"), the pressure-sensitive adhesive sheet was laminated on the stepped glass plate so that the pressure-sensitive adhesive layer covered the entire printing surface of the frame frame.

After the lamination, the medium release type release sheet is peeled off, and a glass plate (manufactured by NSG Flashzone, product name "Corning Glass Eagle XG", length 90mm × width 50mm × thickness 0.5mm) is laminated with the laminator on the surface of the exposed adhesive layer for evaluation samples were made.

(b) Evaluation of step followability (initial)

The obtained sample for evaluation was pressurized for 30 minutes at 0.5 MPa and 50 degreeC in the autoclave made from Kurihara Seisakusho. Thereafter, it was visually confirmed whether or not there were air bubbles in the pressure-sensitive adhesive layer (particularly in the vicinity of the level difference due to the printed layer). As a result, the thing which had no bubble at all was evaluated as (circle), the thing which had few bubbles was evaluated as (circle), and the thing which bubbled was evaluated as x (evaluation of initial stage difference followability). A result is shown in Table 2.

(c) Evaluation of durability (step difference followability after durability)

Next, the samples (1) and (2) for evaluation were stored for 240 hours under moist heat conditions of 85°C and 85%RH. Thereafter, it was visually confirmed whether or not there were air bubbles in the pressure-sensitive adhesive layer (particularly in the vicinity of the level difference due to the printed layer). As a result, the thing with no bubble at all was evaluated as (circle), the thing with few bubbles was evaluated as (circle), and the thing with bubble was evaluated as x (evaluation of durability (evaluation of durability (step difference followability after durability)). A result is shown in Table 2.

[Test Example 5] (Measurement of total light transmittance)

The adhesive layer of the adhesive sheet obtained by the Example or the comparative example was pasted together to glass, and this was made into the sample for a measurement. After performing background measurement with glass, the total light transmittance (%) of the sample for measurement was measured using a haze meter (NDH-2000 manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K7361-1:1997. A result is shown in Table 2.

[Test Example 6] (Evaluation of blister resistance)

A 125-micrometer-thick polyethylene terephthalate film (ITO film made by Oikeko company) was prepared by the specter in which the transparent conductive film which consists of tin-doped indium oxide (ITO) was provided on one side.

The pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained in Examples or Comparative Examples is sandwiched between the transparent conductive film of the ITO film and a polycarbonate plate having a thickness of 1 mm (manufactured by Mitsubishi Gas Chemicals, product name “Upiron Sheet MR58”), A laminate was obtained by irradiating an ultraviolet ray over the polycarbonate plate under the ultraviolet irradiation conditions of Test Example 1.

After autoclaving the obtained laminated body under the conditions of 50 degreeC and 0.5 MPa for 30 minutes, it was left to stand for 15 hours. Then, it was stored for 72 hours under a durable condition of 85°C and 85%RH. Then, it was confirmed visually whether there was foam|bubble, float and peeling in an adhesive layer. As a result, the thing which had no bubble or float and peeling at all was evaluated as (circle), that there were few bubbles, float, and peeling was evaluated as (circle), and the thing which bubble or float and peeling generate|occur|produced was evaluated as x (evaluation of blister resistance). A result is shown in Table 2.

(meth)acrylic acid ester copolymer (A)
active energy ray curability
Component (B)
Crosslinking agent (C) light curing
Initiator (D)
[parts by mass] Silane coupling agent
[parts by mass] adhesive
thickness
(μm) 2EHA BA MMA HEA AA Mw part by mass Kinds part by mass Kinds part by mass Example 1 60 - 20 20 - 600,000 100 A400 25 TDI 0.23 2.5 0.2 200 Example 2 60 - 20 20 - 600,000 100 A400 25 TDI 0.5 2.5 0.2 200 Example 3 - 90 - - 10 400,000 100 A400 25 epoxy 0.08 2.5 0.2 200 Example 4 - 90 - - 10 400,000 100 A9300-1CL 10 epoxy 0.08 One 0.2 200 Comparative Example 1 60 - 20 20 - 600,000 100 - - TDI 0.23 - 0.2 200 Comparative Example 2 - 90 - - 10 400,000 100 - - epoxy 0.08 - 0.2 200 Comparative Example 3 60 - 20 20 - 600,000 100 A400 70 TDI 0.23 7 0.2 200

23℃ storage modulus 85℃ storage modulus machinability Heizuchi
(%) Moisture Heat Whitening Resistance
Step followability and durability blister resistance before UV
[MPa] After UV
[MPa] After UV
/UV before before UV
[MPa] After UV
[MPa] After UV
/UV before Early
(step difference 8㎛) Early
(step difference 15㎛)
durability
(step difference 8㎛) durability
(step difference 15㎛) Example 1 0.14 0.16 1.14 0.02 0.03 1.5 ○ >99 ○ ◎ ◎ ◎ ◎ ○ Example 2 0.10 0.51 5.10 0.01 0.05 5.0 ○ >99 ○ ◎ ◎ ◎ ○ ◎ Example 3 0.03 0.19 6.33 0.01 0.08 8.0 ○ >99 ○ ◎ ◎ ◎ ◎ ○ Example 4 0.10 0.48 4.80 0.02 0.10 5.0 ○ >99 ○ ◎ ◎ ◎ ◎ ○ Comparative Example 1 0.15 0.15 1.00 0.03 0.03 1.0 ○ >99 ○ ◎ ○ ◎ × × Comparative Example 2 0.15 0.15 1.00 0.03 0.03 1.0 ○ >99 ○ ◎ ◎ ◎ ◎ × Comparative Example 3 - - - - - - × - - - - - - -

As can be seen from Table 2, the adhesive sheet obtained in Examples was excellent in workability. Moreover, the adhesive layer obtained in the Example was excellent in step|step difference followability|trackability before ultraviolet irradiation, and was also excellent in moist-heat whitening resistance, durability, and blister resistance after ultraviolet irradiation.

The active energy ray-curable adhesive sheet of this invention can be used suitably for bonding of a display body module and the guard plate which has a level|step difference, especially a plastic plate, for example.

One… Active energy ray-curable adhesive sheet
11… adhesive layer
12a, 12b... release sheet
2… laminate
21… first hard plate
22… 2nd hard plate
3… print layer

Claims (14)

A pressure-sensitive adhesive sheet having an active energy ray-curable pressure-sensitive adhesive layer,
The ratio of the storage modulus at 23° C. before irradiating the pressure-sensitive adhesive layer with the active energy ray to the storage modulus at 23° C. after irradiating the pressure-sensitive adhesive layer with the active energy ray is 1.1 to 10,
Both sides of the pressure-sensitive adhesive layer were sandwiched between two sheets of alkali-free glass having a thickness of 1.1 mm, and the laminate obtained by irradiating an active energy ray through one glass was stored for 240 hours under moist heat conditions of 85° C. and 85% RH, 23 An active energy ray-curable adhesive sheet, characterized in that the haze value increase after the wet heat condition, which is a value obtained by subtracting the haze value (%) before the wet heat condition (%) from the haze value (%) when taken out under normal temperature and humidity at room temperature and humidity of 50% RH, is less than 5.0 points . A pressure-sensitive adhesive sheet having an active energy ray-curable pressure-sensitive adhesive layer,
The ratio of the storage modulus at 85° C. before irradiating the pressure-sensitive adhesive layer with the active energy ray to the storage modulus at 85° C. after irradiating the pressure-sensitive adhesive layer with the active energy ray is 1.1 to 10,
Both sides of the pressure-sensitive adhesive layer were sandwiched between two sheets of alkali-free glass having a thickness of 1.1 mm, and the laminate obtained by irradiating an active energy ray through one glass was stored for 240 hours under moist heat conditions of 85° C. and 85% RH, 23 An active energy ray-curable adhesive sheet, characterized in that the haze value increase after the wet heat condition, which is a value obtained by subtracting the haze value (%) before the wet heat condition (%) from the haze value (%) when taken out under normal temperature and humidity at room temperature and humidity of 50% RH, is less than 5.0 points . 3. The method of claim 1 or 2,
The active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the storage modulus at 23° C. of the pressure-sensitive adhesive layer before irradiation with active energy rays is 0.01 to 0.2 MPa. 3. The method of claim 1 or 2,
The active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the storage modulus at 23° C. of the pressure-sensitive adhesive layer after irradiation with active energy rays is 0.02 to 2 MPa. 3. The method of claim 1 or 2,
The active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the storage modulus at 85° C. of the pressure-sensitive adhesive layer before irradiation with active energy rays is 0.01 to 0.1 MPa. 3. The method of claim 1 or 2,
The active energy ray-curable adhesive sheet, characterized in that the storage modulus at 85°C of the pressure-sensitive adhesive layer after irradiation with active energy rays is 0.02 to 0.5 MPa. 3. The method of claim 1 or 2,
The active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the thickness of the pressure-sensitive adhesive layer is 50 ~ 400㎛. 3. The method of claim 1 or 2,
The adhesive sheet is provided with two release sheets,
The pressure-sensitive adhesive layer is an active energy ray-curable pressure-sensitive adhesive sheet, characterized in that the release sheet is sandwiched in contact with the release surface of the two release sheets. 2 hard plates,
As a laminate having an adhesive layer sandwiched between the two hard plates,
The said adhesive layer is what hardened the adhesive layer of the active energy ray-curable adhesive sheet of Claim 1 or 2 by irradiation of an active energy ray, The laminated body characterized by the above-mentioned. 10. The method of claim 9,
At least one of the hard plates has a level difference on a surface on the pressure-sensitive adhesive layer side. 11. The method of claim 10,
The level difference is a level difference according to the presence or absence of a printed layer. 10. The method of claim 9,
At least one of the hard plates comprises a polarizing plate. 10. The method of claim 9,
At least one of the hard plates comprises a plastic plate. 10. The method of claim 9,
One of the two hard plates is a display module or a part thereof,
The laminate according to claim 1, wherein the other of the two hard plates is a protective plate having a frame-shaped step difference on the surface on the side of the pressure-sensitive adhesive layer.

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