TW201639936A - Adhesive sheet for image display device, adhesive layered body for image display device, and image display device - Google Patents

Abstract

An adhesive sheet for an image display device, in which tan [delta] at 40-70 DEG C is 0.35 or greater, the tensile secant modulus in the tensile stress-strain curve is 0.6-1.4 MPa, and the tensile elongation at break is 150 mm or less.

Description

Adhesive sheet for image display device, adhesive laminate for image display device, and image display device

The present invention relates to an adhesive sheet for an image display device, an adhesive laminate for an image display device, and an image display device.

In recent years, a method has been proposed which replaces a gap between a transparent protective plate or an information input device (for example, a touch panel) in an image display device and a display surface of an image display unit, or a transparent protective plate, with a transparent material. The gap between the information input devices, thereby improving the transmittance and suppressing the decrease in the brightness and contrast of the image display device. The refractive index of the transparent material is closer to the transparent protection plate, the information input device and the image than the air. The display surface of the display unit (for example, Patent Document 1). As an example of the image display device, a schematic view of the liquid crystal display device is shown in FIG. A liquid crystal display device having a touch panel, which is composed of a transparent protection plate D1, a touch panel D2, a polarizing plate D3, and a liquid crystal display cell D4, and is used for preventing rupture, stress and impact of the liquid crystal display device from being recognized and recognized. An adhesive layer (transparent resin layer) D5 is sometimes disposed between the transparent protective plate and the touch panel, and an adhesive layer (transparent resin layer) D6 is further disposed between the touch panel and the polarizing plate. Again, the transparent protection The material of the board is mainly made of glass, but it is being researched and replaced with a plastic which is inexpensive and excellent in impact resistance (polycarbonate or polymethyl methacrylate (hereinafter referred to as PMMA), polycarbonate/PMMA multilayer). ).

However, in the information input device and the image display unit, it is necessary to provide an input/output line at the edge portion thereof, and generally, the line is not visible from the side of the transparent protection plate, and the edge portion of the transparent protection plate is printed by printing or the like. A frame-shaped decorative portion D7 (19 (frame pattern) or the like in the first drawing of Patent Document 1) is provided. In order to eliminate the difference in height due to the decorative portions, for example, a film-like adhesive may be used as the adhesive for bonding the transparent protective sheet, but in order to embed the vicinity of the height difference without a gap, the film may be formed. Adhesives require excellent high and low embedding. In recent years, various film-like adhesives for improving such embedding property have been studied (for example, Patent Document 2 and Patent Document 3).

[Previous Technical Literature] (Patent Literature)

Patent Document 1: Japanese Laid-Open Patent Publication No. 2008-83491

Patent Document 2: Japanese Laid-Open Patent Publication No. 2010-90204

Patent Document 3: International Publication No. 2012/032995

However, as a result of the findings of the present inventors, as shown in FIG. 11, the film-like adhesion as described in Patent Document 2 and Patent Document 3 In the agent D9, when the height of the step portion D7 becomes high, the embedding property of the step is insufficient. In particular, the thickness of the film-like adhesive is gradually reduced, and when the thickness of the film-like adhesive is thin and the height difference is high, the embedding property of the film-like adhesive tends to be further difficult. Further, a method of increasing the embedding property of the adhesive layer by softening the material of the adhesive layer, but the adhesive layer is soft at this time, the step of cutting the adhesive sheet into a specific size (punching processing) is exemplified. In the middle, the adhesive layer will ooze out from the cut surface, and when the separator is peeled off, the adhesive residue is likely to occur (the adhesive layer follows the separator on both sides), and the adhesive sheet cannot maintain a specific shape, so that it is impossible to produce an image display. Device or yield deterioration problem.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an adhesive sheet for an image display device which is excellent in embedding property of a pair of adhesive sheets formed on an adherend, and is processed. The processability is excellent in a process suitable for the shape of the image display device and bonding. Further, an object of the present invention is to provide an adhesive laminate for an image display device and an image display device. The adhesive laminate for the image display device is obtained by using an adhesive sheet for the image display device.

In the image display device of the present invention, the tan δ at 40 to 70 ° C is 0.35 or more, the tensile secant elastic modulus in the tensile stress-strain curve is 0.6 to 1.4 MPa, and the tensile elongation at break is Below 150mm.

The above image display device is preferably an adhesive sheet comprising a copolymer of a monomer mixture containing 50 to 90 parts by mass. (a) an alkyl (meth)acrylate having an alkyl group having 1 to 18 carbon atoms; 10 to 30 parts by mass of (b) a (meth) acrylate having a hydroxyl group; and, 5 to 30 parts by mass ( c) (meth) acrylate having an alicyclic substituent or a tertiary alkyl group.

The above-mentioned image display device is preferably an adhesive sheet, and further contains a crosslinking agent.

The above-mentioned image display device is preferably an adhesive sheet, and further contains an ultraviolet absorber.

It is preferable that the haze value of the adhesive sheet for the image display device is 1.5% or less.

Moreover, the present invention provides an adhesive laminate for an image display device comprising: the adhesive sheet for an image display device; and at least a pair of substrates for holding the adhesive sheet for the image display device Way to layer. According to such an image display device with an adhesive laminate, the adhesive laminate can be easily stored and transported without damaging the adhesive layer.

The present invention provides an image display device comprising: an image display unit; a transparent protection plate; and a transparent resin layer interposed between the image display unit and the transparent protection plate, wherein the transparent resin layer is adhered by the image display device The adhesive layer formed by the sheet or its cured product.

The present invention provides an image display device comprising: an image display unit; a transparent protection panel; a touch panel; and a transparent resin layer interposed between the image display unit and the transparent protection panel, or between the touch panel and the touch panel Between the transparent protective sheets, the transparent resin layer is an adhesive layer formed of the above-mentioned adhesive sheet for image display devices or a cured product thereof.

According to the present invention, it is possible to provide an adhesive sheet for an image display device which is excellent in the embedding property of the adhesive sheet formed on the adherend, and is processed into a shape suitable for the image display device. Excellent workability in the process of bonding. Moreover, according to the present invention, there is provided an adhesive laminate for an image display device and an image display device, wherein the adhesive laminate for the image display device is obtained by using an adhesive sheet for the image display device.

1A, 1B‧‧‧Adhesive laminate

2, D5, D6‧‧‧ adhesive layer

2a, 3a, 4a, 5a‧‧‧ outer edge

3‧‧‧Re-peeling septa

4‧‧‧Light peeling septum

5‧‧‧ Carrier film

7‧‧‧Image display unit

12, D4‧‧‧ liquid crystal display cell

20, 22, D3‧‧‧ polarizing plate

30, D2‧‧‧ touch panel

31, 32‧‧‧ Transparent resin layer

40, D1‧‧‧ transparent protection board (glass or plastic substrate)

50‧‧‧Backlight system

60‧‧‧High and low

100‧‧‧ fixture

101‧‧‧Support film for tensile stress-strain curve evaluation

P1, P2‧‧‧ boards

S‧‧‧sample

D9‧‧‧film adhesive

Fig. 1 is a perspective view showing an embodiment of an adhesive laminate (three-layered object) for an image display device of the present invention.

Fig. 2 is a side cross-sectional view taken along line II-II of Fig. 1.

Fig. 3 is a cross-sectional view showing an embodiment of the image display device of the present invention.

Fig. 4 is a cross-sectional view showing an embodiment of the image display device of the present invention.

Fig. 5 is a perspective view showing an embodiment of the adhesive laminate (four-layered article) of the present invention.

Fig. 6 is a side cross-sectional view taken along line VI-VI of Fig. 5.

Fig. 7 is a schematic view showing a method of measuring a sample using a wide-area dynamic viscoelasticity measuring apparatus.

Fig. 8 is a schematic view showing an example of a support film for evaluating a tensile stress-strain curve.

Figure 9 is an example of a tensile stress-strain curve.

Fig. 10 is a cross-sectional view showing an embodiment of a conventional image display device.

Fig. 11 is a schematic view showing the surface flatness when a conventional adhesive laminate is used.

Preferred embodiments (first embodiment and second embodiment) of the present invention will be described below, but the present invention is not limited to these embodiments at all. In addition, the description of the two embodiments will be described only in the first embodiment, and the description of the second embodiment will be appropriately omitted. In addition, the term "(meth) acrylate" as used herein means "acrylate" or "methacrylate" corresponding thereto. Similarly, the term "(meth)acrylic" means "acrylic acid" or its corresponding "methacrylic acid", and the term "(meth)acrylylene" means "acrylic acid" or its corresponding "Mercaptomethyl methacrylate". Further, in the following, the adhesive layer for an image display device and the adhesive layer for an image display device are also referred to as an adhesive sheet and an adhesive laminate, respectively.

[First Embodiment]

<Adhesive laminated body I (3 layers) for image display device>

The adhesive laminated body 1A for an image display device of the present embodiment includes an adhesive layer and a pair of base material layers for sandwiching the adhesive layer Way to layer. The outer edge of the base material layer preferably protrudes outward from the outer edge of the adhesive layer.

That is, as shown in Fig. 1 and Fig. 2, the adhesive laminate 1A of the present embodiment includes a transparent film-like adhesive layer 2, a heavy-peeling separator 3 (one of the substrates), and a light-peeling separator. 4 (another substrate), the heavy peeling separator 3 and the light peeling separator 4 are laminated so as to sandwich the adhesive layer 2. The outer edges of the heavy peeling spacer 3 and the light peeling spacer 4 are preferably more protruded than the outer edge of the adhesive layer 2. The adhesive layer 2 is, for example, a transparent film disposed between the transparent protective plate and the touch panel or between the touch panel and the liquid crystal display unit in an image display device such as a touch panel display for a mobile terminal. .

The transparent protective plate requires high transparency in order to be able to be used in an image display device. As a representative example of the optically transparent substrate, a glass or polymer substrate including a substrate containing a polymer such as polycarbonate or polyester (for example, polyethylene terephthalate) may be mentioned. And polyethylene naphthalate), polyurethane, poly(meth)acrylate (such as PMMA), polyvinyl alcohol, polyolefin (such as polyethylene, polypropylene and cellulose triacetate); However, it is not particularly limited.

The adhesive layer 2 corresponds to an adhesive sheet for an image display device to be described later. Therefore, in addition to the adhesive force, the adhesive layer 2 can exert more excellent effects on surface flatness.

In the adhesive layer 2 (adhesive sheet) of the present embodiment, the tan δ at 40 to 70 ° C is 0.35 or more, and the tensile secant elastic modulus in the tensile stress-strain curve is 0.6 to 1.4 MPa, and the tensile fracture is extended. The degree is below 150mm. According to such an adhesive sheet, the pair is formed on the adherend The high level difference is excellent in embedding property, and it is excellent in workability in the process of being processed into a shape suitable for the image display device and bonding.

The tan δ of the adhesive layer 2 at 40 to 70 ° C may be 0.35 to 2.0, 0.4 to 2.0 or 0.4 to 1.9. When the tan δ at 40 to 70 ° C is 0.35 or more, the embedding property and surface flatness of the height difference tend to be improved. On the other hand, when tan δ at 40 to 70 ° C is 2 or less, the film formability tends to be improved. Here, in the range of tan δ at 40 to 70 ° C, when the lower limit is set as described above, the meaning of the lower limit means the value of tan δ of the adhesive layer (adhesive sheet) in all temperature regions of 40 to 70 ° C. It is above the lower limit. The upper limit is also the same.

The tensile secant modulus of the adhesive layer 2 may be 0.6 to 1.4 MPa or 0.7 to 1.3 MPa. Furthermore, the tensile secant modulus of the adhesive layer 2 may be 100 to 300 kPa or 120 to 260 kPa. Further, the tensile elongation at break may be 150 mm or less, or may be 130 mm or less or 120 mm or less. If the tensile secant elastic modulus is 0.6 to 1.4 MPa and the tensile elongation at break is 150 mm or less, there is a tendency that the workability is excellent when the adhesive sheet is cut into a specific size, and when assembled to an image display device The operability is also excellent.

The tan δ, the tensile secant modulus, and the tensile elongation at break can be adjusted, for example, by adjusting the composition of the component (A) described later, especially the alkyl group having a carbon number of 4 to 18 (methyl). The composition ratio of the alkyl acrylate to the (meth) acrylate having an alicyclic substituent or a tertiary alkyl group and the (meth) acrylate having a hydroxyl group. In particular, tan δ and stretching The secant elastic modulus tends to be a compensatory relationship, and may be appropriately adjusted by the ratio of the above-described constituent components.

In order to be used in an image display device, the haze of the adhesive layer 2 is preferably 1.5% or less. From the viewpoint of visibility, the haze may be 1.0% or less, 0.8% or less, or 0.5% or less. The lower limit of the haze is preferably close to 0%, but is generally greater than 0%, and may be 0.1% from the viewpoint of practicality.

The haze depends on the component (A) to be described later, and in particular, the composition ratio of the (meth) acrylate containing a hydroxyl group. When the composition ratio of the hydroxyl group-containing (meth) acrylate is high, whitening is not easily caused by the reliability test (heating and humidifying conditions), and the haze can be lowered, which is preferable. The composition ratio may be 10 to 30 parts by mass or 15 to 30 parts by mass. Moreover, as long as the mutual solubility of the component (A) and the component (B) described later is good, the haze can be lowered.

The haze means a value (%) indicating the turbidity, and the total transmittance T _t of the light transmitted through the sample after being irradiated with a lamp and the transmittance T _d of the light diffused and diffused in the sample to ( The method of T _d /T _t )×100 is obtained. These values are specified in accordance with Japanese Industrial Standard (JIS) K 7136, and can be easily measured by a commercially available turbidity meter, such as NDH-5000 manufactured by Nippon Denshoku Industries Co., Ltd.

The thickness of the adhesive layer 2 can be appropriately adjusted depending on the intended use and method, and is not particularly limited, and may be 25 to 200 μm, 25 to 180 μm, or 25 to 150 μm. When the adhesive layer 2 is used in this range, it is particularly excellent as a transparent adhesive sheet for bonding an optical member to a display.

For light in the visible light region (wavelength: 380 to 780 nm), the minimum value of the light transmittance of the adhesive layer 2 may be 80%, 90% or 95%.

Next, the components of the adhesive sheet for an image display device of the present embodiment will be described.

[(A) component: (meth)acrylic derivative polymer]

(A) (meth)acrylic derivative polymer refers to a polymer obtained by polymerizing one monomer having one (meth)acryl fluorenyl group in one molecule, or combining two kinds thereof. The above is carried out for copolymerization. Further, as long as the effect of the present embodiment is not impaired, the component (A) may be a polymer obtained by having a compound having two or more (meth)acrylic acid fluorenyl groups in the molecule or not having a (meth)acrylic acid-based polymerizable compound (a compound having one polymerizable unsaturated bond in a molecule such as acrylonitrile, styrene, vinyl acetate, ethylene, or propylene; or two or more molecules in a molecule such as divinylbenzene; The compound of a polymerizable unsaturated bond) is copolymerized with a (meth)acrylic derivative polymer.

Examples of the monomer for forming the component (A) and having one (meth)acryl fluorenyl group in the molecule include (meth)acrylic acid; (meth)acrylamide; (meth)acrylonitrile group. Morpholine; methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tertiary butyl (meth)acrylate, (methyl) ) n-amyl acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth) acrylate Decyl ester, dodecyl (meth)acrylate (n-lauryl (meth)acrylate), (A) An alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms such as stearyl acrylate; an alkyl ring of (meth) acrylate or phenoxyethyl (meth) acrylate having an aromatic ring ( (meth) acrylate; (meth) acrylate having an alicyclic substituent such as cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate; ) tetrahydrofuran methyl acrylate; (meth) acrylate N, N-dimethylaminoethyl ester, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (Meth) acrylamide, N-isopropyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, etc. Methyl) acrylamide derivatives; 2-(2-methylpropenyloxyethyloxy)ethyl isocyanate, 2-(meth)acryloyloxyethyl isocyanate, etc. having isocyanato groups (meth) acrylate; (meth) acrylate containing an alkane diol chain, and the like.

In the component (A), the alkyl group-containing (meth)acrylate having an alkyl group represented by the following formula (α) and having 1 to 18 carbon atoms is preferable. Moreover, the content ratio of such a (meth) acrylate is preferably 50 to 90% by mass, and more preferably 50 to 85% by mass based on the total mass of the polymer obtained by copolymerization. When the content ratio of the (meth) acrylate represented by the following formula (α) is within such a range, the adhesion between the adhesive layer and the transparent protective sheet can be improved. Such a copolymerization ratio polymer can be generally obtained by blending each monomer in the same ratio as the above copolymerization ratio and subjecting it to copolymerization. Further, the polymerization rate is more preferably set to be substantially close to 100% by mass.

CH ₂ =CXCOOR‧‧‧(α)

In the formula (α), X represents a hydrogen atom or a methyl group, and R represents a primary or secondary alkyl group having 1 to 18 carbon atoms.

Examples of the alkyl (meth)acrylate having 1 to 18 carbon atoms in the alkyl group include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and (methyl). ) isobutyl acrylate, n-amyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethyl (meth) acrylate Hexyl ester, dodecyl (meth)acrylate, stearyl (meth)acrylate, etc.; among them, n-butyl (meth)acrylate, isooctyl (meth)acrylate, (methyl) are preferred. 2-ethylhexyl acrylate, n-octyl (meth) acrylate, more preferably 2-ethylhexyl (meth) acrylate. Further, the alkyl acrylate is more preferable than the alkyl methacrylate. These (meth)acrylic acid alkyl esters can be used in combination of 2 or more types.

The component (A) is preferably another monomer having a hydroxyl group-containing monomer and copolymerized with an alkyl (meth)acrylate having an alkyl group having 1 to 18 carbon atoms. Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth)acrylate, 1-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and (meth)acrylic acid 3- Hydroxypropyl ester, 1-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, (A) Base) 1-hydroxybutyl acrylate or the like; however, it is not particularly limited.

Further, the component (A) may be an alicyclic substituent or a tertiary alkyl group as another monomer which is copolymerized with an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms. Base) acrylate. As the (meth) acrylate having an alicyclic substituent, a (meth) acrylate ring may be mentioned. a (meth) acrylate having an alicyclic substituent such as an ester, isobornyl (meth)acrylate or dicyclopentanyl (meth)acrylate; and (meth) acrylate having a tertiary alkyl group, Tertiary butyl (meth)acrylate, etc.; but is not limited to these monomers. By using these (meth) acrylates having an alicyclic substituent or a tertiary alkyl group, the tan δ of the adhesive layer can be improved, and the tensile elongation at break can be easily shortened, and it is suitable for both high and low embedding and rushing. The case of cutting workability. A (meth) acrylate having an alicyclic substituent or a tertiary alkyl group may be used in combination of two or more kinds.

Further, as the other monomer which is copolymerized with the alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, a monomer having a polar group: N-morpholinyl group, amine group, or the like is preferable. A carboxyl group, a cyano group, a carbonyl group, a nitro group, a group derived from an alkanediol, or the like. By the (meth) acrylate having these polar groups, the adhesion of the adhesive layer to the transparent protective sheet can be improved.

Further, an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms and an alkylene glycol chain-containing (meth) acrylate represented by the following formula (x) can be used in combination.

CH ₂ =CXCOO(C _p H _2p O) _q R‧‧‧(x)

In the formula (x), X represents a hydrogen atom or a methyl group, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, p represents an integer of 2 to 4, and q represents an integer of 1 to 10.

Examples of the (meth) acrylate-containing (meth) acrylate represented by the formula (x) include diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) acrylate, and tetra. Polyethylene glycol mono(meth)acrylate such as ethylene glycol mono(meth)acrylate or hexaethylene glycol mono(meth)acrylate; Propylene glycol mono(meth)acrylate, tripropylene glycol mono(meth)acrylate, propylene glycol mono(meth)acrylate, etc., polypropylene glycol mono(meth)acrylate; dibutylene glycol mono(meth)acrylate Polybutanediol mono(meth)acrylate such as tributyl glycol mono(meth)acrylate; methoxytriethylene glycol (meth) acrylate, methoxytetraethylene glycol (methyl) Acrylate, methoxyhexaethylene glycol (meth) acrylate, methoxy octaethylene glycol (meth) acrylate, methoxy hexaethylene glycol (meth) acrylate, methoxy polyethylene Glycol (meth) acrylate, methoxy heptapropanediol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, butoxyethylene glycol (meth) acrylate, butoxy An alkoxy polyalkylene glycol (meth) acrylate such as bisethylene glycol (meth) acrylate. Further, these (meth) acrylate having an alkylene glycol chain may be used in combination of two or more kinds.

The adhesive sheet may comprise a copolymer of a monomer mixture containing 50 to 90 parts by mass of (a) an alkyl (meth)acrylate having an alkyl group having 1 to 18 carbon atoms, and 10 to 30 parts by mass ( b) a (meth) acrylate having a hydroxyl group, and 5 to 30 parts by mass of (c) a (meth) acrylate having an alicyclic substituent or a tertiary alkyl group.

Further, the adhesive sheet may comprise a copolymer of a monomer mixture, and when the total amount of the copolymer is 100 parts by mass, the monomer mixture contains 50 to 85 parts by mass of (a) an alkyl group having 1 to 18 carbon atoms. (alkyl)alkyl (meth)acrylate, 10 to 20 parts by mass of (b) (meth) acrylate having a hydroxyl group, and 5 to 30 parts by mass of (c) having an alicyclic substituent or a tertiary alkyl group (Meth) acrylate.

The weight average molecular weight of the component (A) is preferably a value obtained by colloidal osmometry (GPC) and using a calibration curve of standard polystyrene, and is a value of 80000 to 700,000. When the weight average molecular weight is 80,000 or more, an adhesive layer having an adhesive force that does not peel off the transparent protective sheet or the like can be obtained. On the other hand, when the weight average molecular weight is 700,000 or less, the viscosity of the adhesive resin composition is not excessively high, and the workability in forming the sheet-like adhesive layer tends to be good. From the above viewpoints, the weight average molecular weight of the component (A) is more preferably from 100,000 to 600,000.

As the polymerization method of the component (A), a known polymerization method such as solution polymerization, emulsion polymerization, suspension polymerization, or bulk polymerization can be used.

As the polymerization initiator which is used in the polymerization of the component (A), a compound capable of generating a radical by heat can be used. Specific examples thereof include organic peroxides such as benzamidine peroxide and lauric acid peroxide; 2,2'-azobisisobutyronitrile and 2,2'-azobis(2-methyl group); An azo compound or the like such as butyronitrile).

[(B) Component: Crosslinker]

Specific examples of the component (B) include a photocrosslinking agent and a thermal crosslinking agent.

As the photocrosslinking agent, a compound represented by the following formulas (a) to (f) can be preferably exemplified. Wherein, in the formulae (a), (b) and (c), s represents an integer of 1 to 20, and in the formulae (d) and (e), m and n each independently represent an integer of 1 to 10.

Further, an amine ester di(meth)acrylate having an amine ester bond can also be used as the component (B).

The amine ester di(meth)acrylate having an amine ester bond preferably has a polyalkylene glycol chain from the viewpoint of good compatibility with other components. Also, from the viewpoint of ensuring transparency, it is preferred to have an alicyclic knot Structure. When the mutual solubility of the component (B) and the component (A) is high, there is a tendency that the cured product is prevented from being cloudy.

The photocrosslinking agent preferably has a weight average molecular weight of 100,000 or less, more preferably 300 to 100,000, still more preferably 500 to 80,000 from the viewpoint of suppressing the occurrence of bubbles and peeling under high temperature or high temperature and high humidity. .

The content of the optical crosslinking agent is preferably 15% by mass or less based on the total mass of the adhesive resin composition. If the content is 15% by mass or less, the crosslinking density does not become too high, so that an adhesive layer having sufficient adhesion and high elasticity and no brittleness can be obtained. In addition, the content of the photocrosslinking agent is more preferably 10% by mass or less, and still more preferably 7% by mass or less from the viewpoint of further improving the embedding property of the level difference.

The lower limit of the content of the photocrosslinking agent is not particularly limited, and is preferably 0.1% by mass or more, more preferably 2% by mass or more, and still more preferably 3% by mass or more from the viewpoint of improving film formability.

As the thermal crosslinking agent, a thermal crosslinking agent such as an isocyanate system, a melamine system or an epoxy resin can be used. Further, as the thermal crosslinking agent, a polyfunctional crosslinking agent such as a trifunctional or tetrafunctional group is more preferable in order to form a gradually enlarged mesh structure in the adhesive.

In the present invention, an isocyanate system is preferred. As the isocyanate type, for example, a polyfunctional hexamethylene diisocyanate compound is preferable. Examples of the polyfunctional hexamethylene diisocyanate compound include a trimer of hexamethylene diisocyanate; or trimethylolpropane or the like. An alcohol, a monofunctional alcohol or a reaction product of a diol and hexamethylene diisocyanate.

When any of the components (A) and (B) is a curing system which is cured by an active energy ray, a photopolymerization initiator is required. The photopolymerization initiator accelerates the hardening reaction by irradiation with an active energy ray. Here, the active energy ray means ultraviolet rays, electron beams, α rays, β rays, γ rays, and the like.

The photopolymerization initiator is not particularly limited, and a known material such as a diphenylketone, an anthraquinone, a benzammonium, an onium salt, a diazonium salt or a phosphonium salt can be used.

Specific examples thereof include diphenyl ketone, N, N, N', N'-tetramethyl-4,4'-diaminodiphenyl ketone (Michler ketone), N, N,N',N'-tetraethyl-4,4'-diaminodiphenyl ketone, 4-methoxy-4'-dimethylaminodiphenyl ketone, α-hydroxyisobutyl ketone Diphenyl ketones such as phenyl ketone; 2-ethyl hydrazine, tert-butyl hydrazine, 1,4-dimethyl hydrazine, 1-chloroindole, 2,3-dichloropurine, 3 -Chloro-2-methylindole, 1,2-benzopyrene, 2-phenylindole, 1,4-naphthoquinone, 9,10-phenanthrenequinone, etc.; thioxanthone , 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-hydroxy-2-methyl-1- An aromatic ketone compound such as phenylpropan-1-one or 2,2-diethoxyacetophenone; a benzoin compound such as benzoin, methylbenzoin or ethyl benzoin; benzoin methyl ether, benzoin ethyl ether, benzoin a benzoin ether compound such as butyl ether or benzoin phenyl ether; a diphenylethylenedione (benzil) compound such as diphenylethylenedione or diphenylethylenedione dimethyl ketal; - (Acridine-9-yl) ester compound such as (meth)acrylic acid; acridine such as 9-phenyl acridine, 9-pyridyl acridine or 1,7-bis(N-acridinyl)heptane a compound; 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2-(p-methoxy Phenyl)-4,5-diphenylimidazole dimer, 2,4-di(p-methoxyphenyl)-5-phenylimidazole dimer, 2-(2,4-dimethoxy 2,4,5-triarylimidazole II, such as phenyl)-4,5-diphenylimidazole dimer, 2-(p-methylmercaptophenyl)-4,5-diphenylimidazole dimer Imidazole dimer such as polymer; 2-benzyl-2-dimethylamino-1-(4-(N-morpholinyl)phenyl)-1-butanone; 2-methyl-1- [4-(Methylthio)phenyl]-2-(N-morpholinyl)-1-propane; fluorenyl group such as bis(2,4,6-trimethylbenzylidene)phenylphosphine oxide A phosphine oxide-based compound; oligomeric (2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)acetone) or the like. These compounds can be used in combination of plural kinds.

In particular, from the viewpoint of reducing haze, preferred are: 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-( α-Hydroxyalkylphenone compound such as 2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one; bis(2,4,6-trimethyl) Benzobenzyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzylidene)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-three a fluorenyl phosphine oxide compound such as methylbenzhydryl-diphenylphosphine oxide; oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)acetone) .

Further, in particular, in order to produce a thick adhesive sheet (adhesive layer), the photopolymerization initiator preferably contains bis(2,4,6-trimethylbenzylidene)-phenylphosphine oxide, bis (2) ,6-dimethoxybenzimidyl)-2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzylidene-diphenylphosphine oxide A phosphine oxide compound.

The content of the photopolymerization initiator in the present embodiment is preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass, still more preferably 0.1 to 0.5% by mass based on the total mass of the adhesive resin composition. %. When the content is 5% by mass or less, there is a tendency that an adhesive layer can be obtained, and the adhesive layer has high transmittance, and the hue does not have yellow color, and the embedding property is also excellent.

[Other additives]

The adhesive resin composition may contain various additives other than the above components (A) and (B) as needed. Examples of the various additives which may be contained include a polymerization inhibitor such as p-methoxyphenol, which is added to improve the storage stability of the adhesive resin composition, and an antioxidant such as triphenyl phosphite for improving A light stabilizer such as a hindered amine light stabilizer (HALS) is added to improve the heat resistance of the adhesive layer obtained by photocuring the adhesive resin composition, in order to improve the adhesion of the adhesive resin composition to ultraviolet rays or the like. Addition of light resistance; a decane coupling agent added to improve adhesion of an adhesive resin composition to glass or the like.

The adhesive display layer for the image display device can be obtained by applying the above adhesive resin composition onto a substrate, when the above adhesive tree When the lipid composition contains an organic solvent, it is dried, and heated or light-irradiated, whereby the adhesive layer 2 is formed, and then another substrate is coated on the adhesive layer 2.

Further, the adhesive resin composition may contain an ultraviolet absorber as needed. The ultraviolet absorber can be used as long as it has a compound which absorbs in the ultraviolet region. Specifically, a benzotriazole-based ultraviolet absorber (for example, ADK STAB LA-29, LA-31, LA-32, and LA-36 manufactured by ADEKA Co., Ltd., and Tinuvin PS manufactured by BASF Corporation of Japan, Tinuvin 99-2, Tinuvin 326, Tinuvin 384-2, Tinuvin 900, Tinuvin 928, and Tinuvin 1130), diphenyl ketone-based ultraviolet absorbers (for example, Uninul 3049 and Uninul 3050 manufactured by BASF Corporation of Japan), and triazine-based ultraviolet absorbers (for example) ADK STAB LA-46 and LA-F70 manufactured by ADEKA Co., Ltd., and Tinuvin 1600, Tinuvin 1577 ED, Tinuvin 400, Tinuvin 405, Tinuvin 460, Tinuvin 477, and Tinuvn 479 manufactured by BASF Corporation of Japan, and the like. These ultraviolet absorbers may be used alone or in combination of two or more. When adjusting the ultraviolet absorption characteristics, it is preferred to combine two or more types. By adding an ultraviolet absorber, it is possible to suppress deterioration of the display device or the optical film over time due to ultraviolet rays.

The heavy release separator 3 may, for example, be a polymer film such as polyethylene terephthalate, polypropylene, polyethylene or polyester. polymer The film is more preferably a polyethylene terephthalate film (hereinafter sometimes referred to as "PET film"). The thickness of the heavy peeling separator 3 may be 50 to 200 μm, 60 to 150 μm or 70 to 130 μm from the viewpoint of workability. The planar shape of the heavy peeling spacer 3 is preferably larger than the planar shape of the adhesive layer 2, and the outer edge 3a of the heavy peeling spacer 3 is more preferably protruded outward than the outer edge of the adhesive layer 2. The width of the outer edge of the heavy release separator 3 that protrudes more than the outer edge of the adhesive layer 2 may be 2 to 20 mm or 4 to be able to reduce the ease of handling, the ease of peeling, and the adhesion of dust or the like. 10mm. When the planar shape of the adhesive layer 2 and the heavy peeling spacer 3 is approximately rectangular such as approximately rectangular, the outer edge of the heavy peeling spacer 3 may protrude more than the outer edge of the adhesive layer 2, and may be 2 to 20 mm on at least one side or 4~10mm, or 2~20mm or 4~10mm on all sides.

Examples of the light release separator 4 include polymer films such as polyethylene terephthalate, polypropylene, polyethylene, and polyester. The polymer film is more preferably a polyethylene terephthalate film. The thickness of the light release separator 4 may be 25 to 150 μm, 30 to 100 μm, or 40 to 75 μm from the viewpoint of workability. The planar shape of the lightly peeling spacer 4 is preferably larger than the planar shape of the adhesive layer 2, and the outer edge of the spacer 4 is lightly peeled off, and more preferably protrudes outward from the outer edge of the adhesive layer 2. The width of the outer edge of the light-peeling separator 4 that protrudes more than the outer edge of the adhesive layer 2 can be 2 to 20 mm or 4 from the viewpoint of ease of handling, ease of peeling, adhesion of dust, and the like. ~10mm. When the planar shape of the adhesive layer 2 and the light-peeling separator 4 is approximately rectangular such as a rectangular shape, the outer edge of the light-peeling separator 4 has a more protruding width than the outer edge of the adhesive layer 2, and may be at least 2 on one side. ~20mm or 4~10mm, or 2~20mm or 4~10mm on all sides.

The peel strength between the light release separator 4 and the adhesive layer 2 is preferably lower than the peel strength between the heavy release separator 3 and the adhesive layer 2. Thereby, the heavy peeling separator 3 is more difficult to peel off from the adhesive layer 2 than the light peeling separator 4. Further, when the adhesive sheet is cut, the blade passes through the adhesive layer 2 toward the heavy peeling separator 3 side, so that the outer edge portion of the adhesive layer 2 is pressed against the heavy peeling separator 3. Thereby, the heavy peeling separator 3 is more difficult to peel off from the adhesive layer 2 than the light peeling separator 4, and the light peeling separator 4 can be peeled off before peeling of the heavy peeling separator 3. Therefore, the spacers 3 and 4 can be peeled off one at a time, and the operation can be performed one by one by peeling off the spacers 3 and 4, and then adhering the adhesive layer 2 to the respective adherends. Further, the peeling strength between the heavy peeling spacer 3 and the adhesive layer 2, and the peeling strength between the light-peeling separator 4 and the adhesive layer 2 can be adjusted, for example, by performing the peeling of the separator 3 The surface of the separator 4 is lightly peeled off. The surface treatment method may, for example, be a release treatment using a polyfluorene-based compound or a fluorine-based compound.

<Method for Producing Adhesive Laminate for Image Display Device I (3 Layer)>

The adhesive laminate of the present embodiment can be produced, for example, by the method described in International Publication No. 2013/161666.

<Image display device>

Next, an image display device manufactured by using the adhesive laminate 1A or an adhesive laminate 1B (four layers) described later will be described. Adhesive laminate 1A The adhesive layer 2 can be applied to various image display devices. Examples of the image display device include a plasma display (PDP), a liquid crystal display (LCD), a cathode ray tube (CRT), a field emission display (FED), an organic electroluminescence display (OELD), a 3D display, and an electronic paper ( EP) and so on. The adhesive layer 2 of the present embodiment can also be used to combine a functional layer such as an antireflection layer, an antifouling layer, a pigment layer, a hard coat layer, and the like, and a transparent protective sheet to which the image display device is attached.

The antireflection layer may be a layer having an antireflection property such that the visible light reflectance is 5% or less, and a layer obtained by treating a transparent substrate such as a transparent plastic film by a known antireflection method may be used. Layer.

The antifouling layer is used to make the stain hard to adhere to the surface, and a known layer composed of a fluorine resin or a polyoxymethylene resin can be used to reduce the surface tension.

The pigment layer is used to improve the color purity, and is used to reduce unnecessary light when the color purity of light emitted from an image display unit such as a liquid crystal display unit cell is low. The pigment layer capable of absorbing an unnecessary portion is dissolved in a resin, and formed or laminated on a base film such as a polyethylene film or a polyester film to obtain the pigment layer.

Hard coating to increase surface hardness. As the hard coat layer, for example, a film obtained by laminating a resin or laminated on a substrate such as a polyethylene film, an acrylic resin such as an amine ester acrylate or an epoxy acrylate, or an epoxy resin can be used. Similarly, in order to increase the surface hardness, it can also be used. An image display device obtained by forming a hard coat layer or laminating a plastic transparent protective plate.

The adhesive layer 2 can be laminated on a polarizing plate for use. At this time, the layer may be laminated on the side of the identification surface of the polarizing plate, and the adhesive layer 2 may be laminated on the opposite side.

When the adhesive layer 2 is used on the identification surface side of the polarizing plate, the anti-reflection layer, the anti-staining layer, and the hard-coat layer may be further laminated on the side of the identification surface of the adhesive layer 2 when used between the polarizing plate and the liquid crystal cell. The functional layer can be laminated on the identification side of the polarizing plate.

When such a laminated body is produced, the adhesive layer 2 can be laminated by using a roll laminator, a vacuum laminator, or a single sheet bonding machine.

The adhesive layer 2 is preferably disposed at a position between the image display unit of the image display device and the frontmost transparent protective plate on the identification side, and is an appropriate position on the identification side. Specifically, it is preferably applied between the image display unit and the transparent protection panel.

In the image display device in which the touch panel and the image display unit are combined, it is preferable that the adhesive layer 2 of the present embodiment is applied between the touch panel and the image display unit and/or the touch panel and Although the adhesive layer 2 of the present embodiment can be applied to the configuration of the image display device, it is not limited to the position described above.

Hereinafter, one of the image display devices, that is, the liquid crystal display device will be taken as an example, and will be described in detail using FIGS. 3 and 4.

Fig. 3 is a side cross-sectional view schematically showing an embodiment of the image display device of the present invention. The image display device shown in FIG. 3 is composed of an image display unit 7 which is sequentially formed by a backlight system 50, a polarizing plate 22, a liquid crystal display cell 12, and a polarizing plate 20; a transparent resin layer 32; The transparent protective plate (protective panel) 40 is disposed on the surface of the transparent resin layer 32. A step portion 60 is provided on the surface of the transparent protective plate 40, thereby forming a height difference. This height difference is in a state of being partially buried by the transparent resin layer 32. Further, the transparent resin layer 32 substantially corresponds to the cured product of the adhesive layer of the present embodiment. The thickness of the step portion 60 varies depending on the size of the liquid crystal display device, etc., and when the thickness is 40 μm to 100 μm, particularly 60 to 100 μm, the use of the adhesive layer of the present embodiment is particularly useful. When the thickness of the step portion 60 is as described above, the thickness of the adhesive layer 2 is preferably thicker from the viewpoint of the embedding property of the height difference, but the adhesive layer 2 of the present invention has a thin film thickness and a height difference. The embedding property is still excellent. When the height of the step portion is h and the thickness of the transparent resin layer is t, even when 0.3 < (h/t) < 1, excellent embedding property can be exhibited.

Fig. 4 is a side cross-sectional view schematically showing a liquid crystal display device in which a touch panel is mounted, which is an embodiment of the image display device of the present invention. The liquid crystal display device shown in FIG. 4 is composed of a video display unit 7 which is sequentially formed by a backlight system 50, a polarizing plate 22, a liquid crystal display cell 12, and a polarizing plate 20; a transparent resin layer 32; , which is disposed on the polarizing plate 20 that becomes the identification side of the liquid crystal display device The touch panel 30 is disposed on the upper surface of the transparent resin layer 32. The transparent resin layer 31 is disposed on the upper surface of the touch panel 30. The transparent protective layer 40 is disposed on the transparent resin layer 31. on the surface. A step portion 60 is provided on the surface of the transparent protective plate 40, thereby forming a height difference. This height difference is in a state of being buried by the partially transparent resin layer 31. Further, the transparent resin layer 31 and the transparent resin layer 32 substantially correspond to the cured product of the adhesive layer 2 of the present embodiment.

Furthermore, in the liquid crystal display device of FIG. 4, a transparent resin layer is interposed between the image display unit 7 and the touch panel 30, and between the touch panel 30 and the transparent protective plate 40, but The transparent resin layer may be at least one of them. In particular, when the adhesive layer 2 of the present embodiment is used, the height difference formed by the step portion 60 provided on the surface of the transparent protective plate 40 is embedded. Therefore, it is preferable to have the transparent resin layer interposed between the touch panel 30. Between the transparent protective plate 40 and the transparent protective plate 40. Moreover, when the touch panel is on-cell, the touch panel and the liquid crystal display unit are integrated. Specific examples thereof include a liquid crystal display device in which the liquid crystal display cell 12 of the liquid crystal display device of Fig. 3 is replaced by a surface-embedded type.

Moreover, in recent years, a liquid crystal display cell called an in-cell touch panel has been developed, which is equipped with a touch panel function. A liquid crystal display device having such a liquid crystal display cell is composed of a transparent protective plate, a polarizing plate, and a liquid crystal display cell (a liquid crystal display cell with a touch panel function), and the adhesive layer 2 of the present embodiment may be It is preferably used in a liquid crystal display device using such an in-cell touch panel.

According to the liquid crystal display device shown in FIG. 3 and FIG. 4, since the adhesive layer of the present embodiment is provided as the transparent resin layer 31 or 32, it has impact resistance and can be obtained without ghost and sharp contrast. High image.

The liquid crystal display unit cell 12 can be a liquid crystal display unit cell composed of a liquid crystal material known in the art. Further, according to the control method of the liquid crystal material, it can be classified into a twisted nematic (TN) method, a super-Twisted Nematic (STN) method, a vertical alignment (VA) method, and an in-plane steering. In the (In-Place-Switching) method or the like, in the present embodiment, a liquid crystal display cell using any of the control methods may be used.

As the polarizing plate 20 and the polarizing plate 22, a polarizing plate generally used in the art can be used.

The surfaces of these polarizing plates can be subjected to anti-reflection, anti-fouling, hard coating, and the like.

Such a surface treatment can be performed on one side of the polarizing plate or on both sides thereof.

As the touch panel 30, there are the following types: a resistive film type in which electrodes are brought into contact by pressure of a finger or an object contacting a surface; and a capacitive type capable of sensing a change in capacitance when a finger or an object touches a surface; electromagnetic induction The adhesive layer 2 of the present embodiment is particularly preferably used for a liquid crystal display device using a capacitive touch panel. As the touch panel 30, a touch panel generally used in the technical field can be used. As the capacitive touch panel, for example, a touch panel having the following structure can be cited: A transparent electrode is formed on the substrate. Examples of the substrate include a glass substrate, a polyethylene terephthalate film, and a cycloolefin polymer film. Further, examples of the transparent electrode include metal oxides such as indium tin oxide (ITO). The thickness of the above substrate is 20 to 1000 μm. Further, the thickness of the transparent electrode is 10 to 500 nm.

Further, when the adhesive layer of the present embodiment is used for a capacitive touch panel, it is preferable that the dielectric constant of the adhesive layer 2 is within an appropriate range. The dielectric constant of the adhesive layer 2 at 100 kHz at room temperature (25 ° C), for example, when the adhesive layer 2 is used between the touch panel and the transparent protective plate, it may be 2.0 to 4.5, 2.0 to 4.0 or 3.5~ 4.0. When the dielectric constant is 2.0 or more, the responsiveness of the touch panel can be sufficiently ensured. If it is 4.0 or less, there is a tendency that the erroneous operation due to excessive responsiveness can be sufficiently reduced.

The transparent resin layer 31 or 32 can be formed to have a thickness of 0.02 to 3 mm. In particular, in the adhesive layer 2 of the present embodiment, a thick film can be formed, and further excellent effects can be exhibited, and it can be preferably used in the case of forming the transparent resin layer 31 or 32 of 100 to 500 μm.

As the transparent protective plate 40, a general transparent substrate for optics can be used. Specific examples thereof include a plate of an inorganic material such as a glass substrate or a quartz plate; a plastic substrate such as an acrylic resin substrate, a carbonate plate or a cycloolefin polymer plate; and a resin sheet such as a thick polyester sheet. When a high surface hardness is required, it may be a glass substrate or an acrylic resin substrate, and more preferably a glass substrate. Anti-reflection and anti-reflection of the surface of these transparent protective plates Treatment by dirt, hard coating, etc. Such a surface treatment can be carried out on one or both sides of the transparent protective sheet. Transparent protection board can also be used in combination.

The backlight system 50 is typically constituted by a reflecting means such as a reflecting plate and an illumination means such as a lamp.

<Method of Manufacturing Image Display Device>

The video display device of the present embodiment can be manufactured by, for example, the method described in International Publication No. 2013/161666.

In the assembly of the image display device or the like, the adhesive laminate 1A can be used as follows. First, the light release separator 4 is peeled off from the adhesive laminate 1A to expose the adhesive surface 2b of the adhesive layer 2. Then, the adhesive surface 2b of the adhesive layer 2 is adhered to the first adherend, and the adhesive layer 2 is pressed against the second adherend by a roller or the like. At this time, the level difference portion 60 provided on the surface of the first adherend is embedded by the flow of the adhesive layer 2. When the adhesive layer 2 is pressed against the adherend, the adhesive layer 2 can be heated to, for example, 40 to 80 °C. By heating the adhesive layer 2 to 40 to 80 ° C, the adhesive layer 2 can be more easily flowed, and the effect of embedding the height difference portion 60 can be obtained more remarkably. This temperature may be 50 to 70 ° C from the viewpoint of further eliminating bubbles in the vicinity of the height difference. The second adherend is, for example, an image display unit, a transparent protective plate, or a touch panel. Then, the heavy release separator 3 is peeled off from the adhesive layer 2 to expose the adhesive surface of the adhesive layer 2. Then, the adhesive surface of the adhesive layer 2 is adhered to the second adherend, and subjected to heat and pressure treatment (autoclave treatment). The second adherend is, for example, an image display unit, a transparent protective plate, or a touch panel. In this way, the adherends can be bonded to each other via the adhesive layer 2. Furthermore, the heating and pressurizing treatment conditions at this time have a temperature of 40 ° C to 80 ° C and a pressure of 0.1 MPa to 0.6 MPa. When the height difference of the surface of the adherend is 30 μm to 1.0 × 10 ² μm, the temperature can be further removed. From the viewpoint of the bubbles in the vicinity of the height difference, the temperature is preferably from 50 ° C to 70 ° C and the pressure is from 0.2 MPa to 0.5 MPa. Further, the processing time is preferably from 5 minutes to 60 minutes, more preferably from 10 minutes to 30 minutes.

In the above step, the transparent resin layer is disposed between the first adherend and the second adhesive, and the transparent resin layer is the adhesive layer 2 or a cured product thereof. The adhesive layer 2 (transparent resin layer) can be disposed between the transparent protective plate and the touch panel or between the touch panel and the image display unit.

The liquid crystal display device of Fig. 3 can be manufactured by interposing the adhesive layer 2 of the present embodiment between the image display unit 7 and the transparent protective plate 40 to obtain a laminated body. That is, in the image display device described in Fig. 3, the adhesive layer 2 of the present embodiment can be laminated on the upper surface of the polarizing plate 20 by a lamination method.

The liquid crystal display device of FIG. 4 can be manufactured by interposing the adhesive layer 2 of the present embodiment between the image display unit and the touch panel, and/or between the touch panel and the transparent protective plate. Get a laminate.

According to the method of manufacturing an image display device of the present invention, it is possible to manufacture an image display device in which the visibility of the image display device is suppressed. By using the adhesive sheet of the present embodiment, for example, an image display unit such as the following can be used. The components (optical members, etc.) required for the image display device are attached to each other: an image display unit such as a liquid crystal display cell and a touch panel, the image display unit and the transparent protective plate, the touch panel, and the transparent protective plate. The manufacturing method of the present embodiment is particularly useful when the adherend is a transparent protective plate and a touch panel, or a transparent protective plate and an image display unit. Similarly, by using the adhesive sheet of the present embodiment, members closer to the identification side than the image display unit of the image display device can be bonded to each other. At this time, for example, even if the transparent protective plate on the identification side has a step along the outer edge thereof, the adhesive layer can surely embed the height difference, and therefore it is presumed that the visibility is not lowered.

[Second embodiment]

<Adhesive laminated body II (4 layers) for image display device>

The adhesive laminated body 1B for an image display device of the present embodiment includes a film-like adhesive layer, first and second base material layers which are laminated so as to sandwich an adhesive layer, and a carrier layer which is further laminated 2 on the substrate layer; and the outer edges of the first substrate layer and the carrier layer protrude outward from the outer edge of the adhesive layer.

That is, as shown in Fig. 5 and Fig. 6, the adhesive laminate 1B of the present embodiment includes a transparent film-like adhesive layer 2, a light-peelable separator 4 (first base material layer), and a heavy-peeling separator. 3 (second base material layer) which is laminated so as to sandwich the adhesive layer 2; and a carrier film 5 (carrier layer) which is further laminated on the heavy release separator 3.

The outer edge 5a of the carrier film 5 protrudes outward from the outer edge 2a of the adhesive layer 2. Thereby, the carrier film 5 can be easily peeled off by the self-heavy peeling spacer 3 by grasping the outer edge portion of the carrier film 5 which protrudes outside the orientation. Carrier The outer edge 5a of the film 5 protrudes outward from the outer edge 4a of the light-peeling separator 4. Thereby, the outer edge portion of the carrier film 5 is further easily grasped, so that the carrier film 5 can be more easily peeled off. The width of the carrier film 5 which is more prominent than the outer edge 4a of the light-peelable separator 4 can be 0.5 to 10 mm from the viewpoint of further reducing the ease of handling, ease of peeling, adhesion of dust, or the like. 1~5mm. When the planar shape of the carrier film 5, the adhesive layer 2, the heavy release spacer 3, and the light release spacer 4 is slightly rectangular, such as a rectangle, the portion of the carrier film 5 that protrudes more than the outer edge 4a of the light release spacer 4 The width can be 0.5~10mm or 1~5mm on at least one side, or 0.5~10mm or 1~5mm on all sides.

According to the adhesive laminate 1B, the outer edges of the separator 4 and the carrier film 5 are lightly peeled off and protrude outward from the outer edge 2a of the adhesive layer 2, so that the adhesive layer can be reliably stored or conveyed. Protect the outer edge of the adhesive layer. When the adhesive layer 2 is adhered to the adherend, the carrier film 5 can be easily peeled off by the self-heavy peeling spacer 3 by grasping the outer edge portion of the carrier film 5 which protrudes outward. Then, by grasping the outer edge 4a of the light-peeling separator 4, the light-peeling separator 4 can be easily peeled off. At this time, the heavy peeling spacer 3 remains on one side of the adhesive layer 2, and therefore, when one side of the adhesive layer 2 is adhered to the adherend, the separator 3 can be maintained by peeling off the spacer 3 Protection of the adhesive layer. Thereafter, the heavy peeling separator 3 is peeled off, and the other surface of the adhesive layer 2 is adhered to the other adherend, whereby the adhesive layer 2 can be disposed between the pair of adherends.

The heavy peeling separator 3 is protected by the carrier film 5 until the previous step, so that the surface of the heavy peeling separator 3 is less damaged. Thereby, can It is easy to visually confirm the damage of the adhesive layer 2, and it is possible to remove the adhesive layer 2 which has been damaged before adhering to the adherend.

The carrier film 5 may, for example, be a polymer film such as polyethylene terephthalate, polypropylene, polyethylene or polyester. The polymer film may be a polyethylene terephthalate film. The thickness of the carrier film 5 may be 15 to 100 μm, 20 to 80 μm or 20 to 50 μm from the viewpoint of workability.

The peeling strength between the light-peeling separator 4 and the adhesive layer 2 is lower, and the peeling strength between the specific gravity peeling separator 3 and the adhesive layer 2 is lower. The peeling strength between the carrier film 5 and the heavy peeling separator 3 is lower than the peeling strength between the specific gravity peeling separator 3 and the adhesive layer 2. Here, the peeling strength between the carrier film 5 and the heavy peeling separator 3 is more preferably lower than the peeling strength between the light-peeling separator 4 and the adhesive layer 2, but may be higher.

The peeling strength between the carrier film 5 and the heavy release separator 3 can be adjusted, for example, by providing an adhesive layer or the like between the carrier film 5 and the heavy release separator 3. The above peel strength can be adjusted depending on the type of the adhesive layer formed and the thickness of the adhesive layer. The type of the adhesive formed between the carrier film 5 and the heavy release separator 3 may, for example, be an acrylic adhesive. The thickness of the adhesive layer formed between the carrier film 5 and the heavy release separator 3 may be 0.1 to 10 μm or 1 to 5 μm.

In this way, according to the adhesive laminate 1B of the present embodiment, the spacers 3 and 4 and the carrier sheet 5 can be easily peeled off while protecting the adhesive layer 2 while being surely in a specific order without peeling.

<Method for Producing Adhesive Laminate for Image Display Device II (4 Layers)>

The adhesive laminate 1B (four-layered material) of the present embodiment can be used in the same manner as the adhesive laminate of the first embodiment, except that the carrier film 5 is peeled off from the heavy-weight peeling separator 3 at the beginning.

<Method of Manufacturing Image Display Device>

The adhesive laminate 1B (four-layered material) of the present embodiment can be used in the same manner as the adhesive laminate of the first embodiment, except that the carrier film 5 is peeled off from the heavy-weight peeling separator 3 at the beginning.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to the embodiments described above, and various modifications may be made without departing from the spirit and scope of the invention.

[Examples]

The invention is illustrated by the following examples. Furthermore, the invention is not limited to the embodiments.

<evaluation>

Each of the adhesive sheets or laminates obtained in each of the examples and the comparative examples was evaluated by the following test method.

1. Determine the storage elastic modulus and tan δ

A 10 mm × 10 mm × 0.5 mm (thickness) adhesive sheet was produced, and then a wide-area dynamic viscoelasticity measuring apparatus (Solids Analyzer RSA-II manufactured by Pheometric Scientific) was used to shear the sandwich mode at a frequency of 1.0 Hz. , measure the temperature range -20 ~ 100 ° C conditions, and heat up The measurement was carried out at a speed of 5 ° C / min. Specifically, as shown in Fig. 7, the sample S is sandwiched between the plate P1 at both ends and the center plate P2 by using the jig 100 as a measurement sample.

2. Tensile secant elastic modulus and tensile elongation elongation evaluation

The prepared adhesive laminate was cut into two pieces of a size of 100 mm × 100 mm × 0.125 mm, and the light release separators were peeled off, respectively, and then adhered in such a manner that the adhesive layers contact each other, and then cut into a size of 50 mm × 50 mm × 0.250 mm. .

At 25 ° C and atmospheric pressure, a rubber roller (roller diameter: 50 mm, roll width: 210 mm) was used, and the two sides of the cut adhesive laminate were adhered to a long side of 70 mm at a pressure of 0.07 MPa. The tensile stress-strain curve of the short side 50 mm × 0.100 mm (thickness) was evaluated on the long side of the polyethylene terephthalate film (COSMOSHINE A4300 manufactured by Toyobo Co., Ltd.) of the support film, and was not attached. The size of the bonded adhesive layer was 10 mm in length × 50 mm in width.

Then, the heavy peeling separator on the other adhesive layer side which is not attached to the polyethylene terephthalate film is peeled off to prepare a film 101 for tensile stress-strain curve evaluation as shown in FIG. . The sample obtained above was subjected to a tensile tester (manufactured by ORIENTEC CORPORATION, trade name: RTC-1210) to grasp the polyethylene terephthalate portion of the sample, and in an environment of 23 ° C, The tensile stress-strain curve was obtained by measuring at a tensile speed of 300 mm/min.

An example of the obtained tensile stress-strain curve is shown in Fig. 9. The tensile elongation at break is a strain (mm) measured until the fracture of the adhesive layer is broken, and the elastic modulus of the tensile secant is calculated according to the following formula.

Esc: tensile tangential elastic modulus (MPa [kgf/mm ² ]) from the start of stretching to the strain increase of 3 mm

Fs: required load (tensile stress) (N[kgf]) from the start of stretching to the strain of 3 mm

ε: specified strain = 3 mm

A: Average cross-sectional area of the test specimen before stretching (mm ² )

Esc=Fs/(ε×A)

3. Evaluation of high and low embedding

The prepared adhesive laminate was cut into a size of 50 mm × 80 mm × 0.125 mm. At 25 ° C and atmospheric pressure, a rubber roller (roll diameter: 50 mm, roll width: 210 mm) was used, and the cut adhesive layer was adhered to a size of 58 mm × 86 mm × 0.125 mm (thickness) at a pressure of 0.07 MPa. The ITO film (300R manufactured by Toyobo Co., Ltd.).

Then, at 25 ° C and atmospheric pressure, a rubber roller (roller diameter: 50 mm, roll width: 210 mm) was used, and a glass substrate having a high and low difference portion was sandwiched by a pressure of 0.07 MPa. The thickness of 0.7 mm) was adhered to the other adhesive layer side to which the ITO film was not bonded, and the height difference portion was obtained by printing the outer peripheral portion so as to have a thickness of 35 μm. Further, the glass substrate having the step portion printed with the outer peripheral portion has the same outer dimension as the ITO film and has an inner dimension of 45 mm × 68 mm. Opening. The glass substrate is used as an input device or an alternative to the image display device to perform evaluation of embedding.

Thereafter, autoclave treatment (45 ° C, 0.5 MPa) was carried out for 20 minutes to prepare a sample. The obtained sample was placed in the following environmental conditions and treated for a specific period of time, after which the sample was taken out for evaluation.

(environmental conditions)

(1) High temperature and high humidity test

The sample was placed under conditions of 85 ° C and 85% relative humidity (RH) for 24 hours.

(2) High temperature test

The sample was placed at 85 ° C for 24 hours.

(3) Thermal cycle test

The following thermal cycle (20 times) was carried out: the sample was placed in an environment of -30 ° C for 30 minutes and then placed in an environment of 85 ° C for 30 minutes.

(assessment basis)

A: No peeling or bubbles occurred

B: The case where there is no peeling and the number of bubbles on the side of 1 to 2 is one or more but less than five.

C: The case where more than 5 bubbles occur

4. Punching processability assessment

The adhesive laminate body as shown in Fig. 2 was cut into a size of 100 mm × 200 mm, and a flat punching type punching device (manufactured by Taiwan Wanrong Machinery Co., Ltd.) was used, and processed into a size of 80 mm × 135 mm. Punching blade (manufactured by Shuangfeng Gold Co., Ltd., pinnacle blade, inner blade 10°/outer edge 25°), punching the sample of the laminated body at 25 ° C under atmospheric pressure to evaluate the processability The adhesive laminated body was formed with the adhesive layer 2 in a thickness of 125 μm on the heavy peeling separator 3 (Cerapeel BX8, 50 μm manufactured by Toray Film Processing Co., Ltd.), and light peeling was formed on the adhesive layer 2. Septum 4 (Cerapeel BKE, manufactured by Toray Film Processing Co., Ltd., 50 μm).

(assessment basis)

n=10 pieces of the sample, peeling the light-peeling separator from the corner to the diagonal direction within 3 to 5 seconds with a peeling angle of 180°. At this time, the residual glue was evaluated (the adhesive layer self-weight peeling spacer floated) The incidence of the situation).

A: 0% occurs

B: 10~50%

C: 60% or more occurs

5. Determination of haze

The produced adhesive laminate was cut into a size of 50 mm × 50 mm × 0.125 mm (thickness). The cut adhesive sheet was placed under conditions of 85 ° C and 85% RH for 24 hours, after which the adhesive sheet was taken out, and a turbidity meter (manufactured by Nippon Denshoku Industries Co., Ltd.) was used in the state of a single layer of optical adhesive (OCA). , trade name: NDH-5000) to carry out the measurement.

6. Determination of UV absorption

The prepared adhesive sheet was cut into a size of 30 mm × 30 mm × 0.125 mm (thickness). The cut piece was adhered to soda lime glass (thickness 0.5 mm) to prepare a test piece. Use UV-visible - A near-infrared spectrophotometer (manufactured by JASCO Corporation, machine name "V570") was used to measure the light transmittance of the produced test piece in the wavelength region of 200 to 800 nm, and the light transmittance at 380 nm was read.

Production Example 1: Synthesis of (A) (meth)acrylic derivative polymer A-1

36.0 g of 2-ethylhexyl acrylate (2-EHA), 12.0 g of cyclohexyl acrylate, 9.0 g of 2-hydroxyethyl acrylate (2-HEA), and 3.0 g of A were taken as starting monomers. Methyl methacrylate (MMA), 100.0 g of ethyl acetate and 20 g of toluene, into a reaction vessel with a cooling tube, a thermometer, a stirring device, a dropping funnel and a nitrogen inlet tube, and then a volume of 100 mL/min. The nitrogen substitution was carried out, and it was heated from normal temperature (25 ° C) to 80 ° C over 15 minutes.

Thereafter, while maintaining a temperature of 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the solution was further reacted for 2 hours. The solution was obtained in the following manner: 24.0 g as an additional monomer was added. 2-ethylhexyl acrylate, 8.0 g of cyclohexyl acrylate, 6.0 g of 2-hydroxyethyl acrylate and 2.0 g of methyl methacrylate were dissolved in 1.0 g of laurel peroxide.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 440,000) ((meth)acrylic derivative polymer A-1) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight is carried out by using colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and using The following apparatus and measurement conditions were determined using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

Refractive Index (RI) Detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

Production Example 2: Synthesis of (A) (meth)acrylic derivative polymer A-2

36.0 g of 2-ethylhexyl acrylate, 12.0 g of isobornyl acrylate (IBXA), 9.0 g of 2-hydroxyethyl acrylate, 3.0 g of methyl methacrylate, 100.0 g were taken as starting monomers. Ethyl acetate and 20 g of toluene were placed in a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and a nitrogen introduction tube, and then subjected to nitrogen substitution at a flow rate of 100 mL/min for 15 minutes. Heat to 80 ° C at room temperature (25 ° C).

Thereafter, while maintaining a temperature of 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the solution was further reacted for 2 hours. The solution was obtained in the following manner: 24.0 g as an additional monomer was used. 2-ethylhexyl acrylate, 8.0 g of isobornyl acrylate, 6.0 g of 2-hydroxyethyl acrylate and 2.0 g of methyl methacrylate were dissolved in 1.0 g of laurel peroxide.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 450,000) ((meth)acrylic derivative polymer A-2) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight was carried out by colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and was determined using the following apparatus and measurement conditions and using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

RI detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

Production Example 3: Synthesis of (A) (meth)acrylic derivative polymer A-3

36.0 g of 2-ethylhexyl acrylate, 12.0 g of butyl methacrylate, 9.0 g of 2-hydroxyethyl acrylate, 3.0 g of methyl methacrylate, and 100.0 g were taken as starting monomers. Ethyl acetate and 20 g of toluene were placed in a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and a nitrogen introduction tube, and then subjected to nitrogen substitution at a flow rate of 100 mL/min for 15 minutes. Heat to 80 ° C at room temperature (25 ° C).

Thereafter, while maintaining the temperature at 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the reaction was further made 2 small. At the time, the solution was obtained by using 24.0 g of 2-ethylhexyl acrylate as an additional monomer, 8.0 g of butyl methacrylate, 6.0 g of 2-hydroxyethyl acrylate, and 2.0 g. Methyl methacrylate was dissolved in 1.0 g of laurel peroxide.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 44000) ((meth)acrylic derivative polymer A-3) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight was carried out by colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and was determined using the following apparatus and measurement conditions and using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

RI detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

Production Example 4: Synthesis of (A) (meth)acrylic derivative polymer A-4

Taking 36.0 g of 2-ethylhexyl acrylate, 15.0 g of isobornyl acrylate, 9.0 g of 2-hydroxyethyl acrylate, 100.0 g of ethyl acetate and 20 g of toluene as starting monomers, a reaction tube of a cooling tube, a thermometer, a stirring device, a dropping funnel, and a nitrogen introduction tube, The latter side was purged with nitrogen at a flow rate of 100 mL/min, and heated from room temperature (25 ° C) to 80 ° C over 15 minutes.

Thereafter, while maintaining a temperature of 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the solution was further reacted for 2 hours. The solution was obtained in the following manner: 24.0 g as an additional monomer was used. 2-ethylhexyl acrylate, 10.0 g of isobornyl acrylate, 6.0 g of 2-hydroxyethyl acrylate, and 1.0 g of laurel peroxide were dissolved therein.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 425,000) ((meth)acrylic derivative polymer A-4) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight was carried out by colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and was determined using the following apparatus and measurement conditions and using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

RI detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

Production Example 5: Synthesis of (A) (meth)acrylic derivative polymer A-5

Taking 36.0 g of 2-ethylhexyl acrylate, 15.0 g of methyl methacrylate, 9.0 g of 2-hydroxyethyl acrylate, 100.0 g of ethyl acetate and 20 g of toluene as starting monomers, The reaction vessel was placed in a reaction vessel of a cooling tube, a thermometer, a stirring device, a dropping funnel, and a nitrogen introducing tube, and then nitrogen gas was substituted at a flow rate of 100 mL/min, and heated from room temperature (25 ° C) to 80 ° C for 15 minutes.

Thereafter, while maintaining a temperature of 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the solution was further reacted for 2 hours. The solution was obtained in the following manner: 24.0 g as an additional monomer was used. 2-ethylhexyl acrylate, 10.0 g of methyl methacrylate, 6.0 g of 2-hydroxyethyl acrylate, and 1.0 g of laurel peroxide were dissolved therein.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 455,000) ((meth)acrylic derivative polymer A-5) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight was carried out by colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and was determined using the following apparatus and measurement conditions and using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

RI detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

Production Example 6: Synthesis of (A) (meth)acrylic derivative polymer A-6

40.0 g of butyl acrylate (BA), 9.0 g of methyl acrylate (MA), 20.0 g of 2-hydroxypropyl acrylate (2-HPA), 100.0 g of ethyl acetate and 20 g were taken as starting monomers. The toluene was placed in a reaction vessel equipped with a cooling tube, a thermometer, a stirring device, a dropping funnel, and a nitrogen introduction tube, and then subjected to nitrogen substitution at a flow rate of 100 mL/min, and heated from normal temperature (25 ° C) for 15 minutes. Up to 80 ° C.

Thereafter, while maintaining a temperature of 80 ° C, a solution was prepared and it took 60 minutes to drip the solution, and after the completion of the dropwise addition, the reaction was further carried out for 2 hours. The solution was obtained in the following manner: 17.0 g was used as an additional monomer. Butyl acrylate, 4.0 g of methyl acrylate, 10.0 g of 2-hydroxypropyl acrylate, and 1.0 g of laurel peroxide were dissolved therein.

Then, 13 g of ethyl acetate and 20 g of toluene were added to obtain a solution of a copolymer resin (weight average molecular weight: 405,000) ((meth)acrylic derivative polymer A-6) having a solid concentration of 40%.

Further, the measurement of the weight average molecular weight was carried out by colloidal permeation chromatography using tetrahydrofuran (THF) as a solvent, and was determined using the following apparatus and measurement conditions and using a calibration curve of standard styrene.

Device: Hitachi, Ltd.

RI detector: L-3350

Use solvent: THF

Pipe column: Gelpac GL-R420+R430+R440 manufactured by Hitachi Chemical Co., Ltd.

Column temperature: 40 ° C

Flow rate: 2.0mL/min

<Preparation of Adhesive Composition for Image Display Device and Preparation of Adhesive Laminate>

(Example 1)

With respect to 99.8 parts by mass of the solid component of the (meth)acrylic derivative polymer A-1 solution obtained in Production Example 1, 0.2 parts by mass of a polyfunctional hexamethylene diisocyanate compound as a thermal crosslinking agent was weighed ( CORONATE HL) manufactured by Japan Polyurethane Industry Co., Ltd., and stirred and mixed to obtain an adhesive resin composition for an adhesive sheet.

Thereafter, the adhesive sheet was dropped on the polyethylene terephthalate film whose surface was subjected to release treatment with an adhesive resin composition, and coated with a bar coater to have a thickness of 125 μm after drying. Then, it was dried by heating at 100 ° C for 10 minutes. Thereafter, the release-treated polyethylene terephthalate film was coated on the coated surface side, and bonded by a 1.0 kgf hand roller to obtain a transparent adhesive laminate. The results of evaluation of the adhesive laminate by the above method are shown in Table 1.

(Example 2)

The acrylic acid derivative polymer A-2 obtained in Production Example 2 was used instead of the (meth)acrylic derivative polymer A-1, and further, Example 1 was carried out in the same manner to obtain an adhesive laminate. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

(Example 3)

The acrylic derivative polymer A-3 obtained in Production Example 3 was used instead of the (meth)acrylic derivative polymer A-1, and the adhesive layered body was obtained in the same manner as in Example 1. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

(Example 4)

0.8 parts by mass of benzotriazole-based compound 1 (Tinuvin 326 manufactured by BASF Corporation, Japan) and 1.0 part by mass of benzotriazole-based compound 2 (Tinuvin 928 manufactured by BASF Corporation, Japan) were weighed as obtained in Example 3 The adhesive sheet is made of an adhesive resin composition and stirred and mixed to obtain an adhesive resin composition for an adhesive sheet. Hereinafter, the results of evaluation and evaluation in the same manner as in Example 1 are shown in Table 1.

(Comparative Examples 1 and 2)

The acrylic acid derivative polymer A-4 obtained in Production Example 4 was used instead of the (meth)acrylic derivative polymer A-1, and was prepared as shown in Table 1, and further, Example 1 was used. The same way is done to obtain an adhesive laminate. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

(Comparative Example 3)

The acrylic acid derivative polymer A-5 obtained in Production Example 5 was used instead of the (meth)acrylic derivative polymer A-1, and further, Example 1 was carried out in the same manner to obtain an adhesive laminate. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

(Comparative Examples 4 and 5)

The acrylic acid derivative polymer A-6 obtained in Production Example 6 was used instead of the (meth)acrylic derivative polymer A-1, and was prepared as shown in Table 1, and further, Example 1 was used. The same way is done to obtain an adhesive laminate. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

[Table 1]

1A‧‧‧Adhesive laminate

2‧‧‧Adhesive layer

3‧‧‧Re-peeling septa

4‧‧‧Light peeling septum

Claims (8)

An adhesive sheet for an image display device has a tan δ of 0.35 or more at 40 to 70 ° C, a tensile secant elastic modulus of 0.6 to 1.4 MPa in a tensile stress-strain curve, and a tensile elongation at break of 150 mm. the following. An adhesive sheet for an image display device according to claim 1, wherein the monomer mixture contains: 50 to 90 parts by mass of (a) an alkyl group having 1 to 18 carbon atoms ( (meth)acrylic acid alkyl ester; 10 to 30 parts by mass of (b) (meth) acrylate having a hydroxyl group; and, 5 to 30 parts by mass of (c) having an alicyclic substituent or a tertiary alkyl group ( Methyl) acrylate. The adhesive sheet for an image display device according to claim 2, further comprising a crosslinking agent. The adhesive sheet for an image display device according to any one of claims 1 to 3, further comprising an ultraviolet absorber. The adhesive sheet for an image display device according to any one of claims 1 to 4, wherein the haze value is 1.5% or less. An adhesive layer for an image display device, comprising: the adhesive sheet for an image display device according to any one of claims 1 to 5; At least one pair of substrates which are laminated so as to sandwich the adhesive sheet for the image display device. An image display device comprising: an image display unit; a transparent protection plate; and a transparent resin layer interposed between the image display unit and the transparent protection plate, wherein the transparent resin layer is requested by any one of claims 1 to 5 An adhesive layer formed by the adhesive sheet of the image display device or a cured product thereof. An image display device comprising: an image display unit; a transparent protection plate; a touch panel; and a transparent resin layer interposed between the image display unit and the transparent protection plate, or between the touch panel and the foregoing The transparent resin layer is an adhesive layer formed of the adhesive sheet for image display devices according to any one of claims 1 to 5, or a cured product thereof.