KR20190024605A - Adhesive sheet, display, and method for manufacturing display - Google Patents

Abstract

The present invention provides an adhesive sheet having excellent blister resistance even under stringency high-temperature and high-humidity conditions, a display, and a method of manufacturing the display. To this end, provided is an adhesive sheet (1) including an adhesive layer (11) for adhering one display-forming member (21) and the other display-forming member (22), wherein at least one of the one display-forming member (21) and the other display-forming member (22) is formed of a plastic plate. In addition, adhesive forming the adhesive layer (11) is obtained from an adhesive composition, containing (A) (meth)acrylate ester polymers containing more than or equal to 10 mass% and equal to or less than 50 mass% of a monomer having a hydroxyl group in a molecule as a monomer forming a polymer, (B) a cross-linking agent, (C) an active energy ray-curable component, and (D) a photo-polymerization initiator having an absorbance at a wavelength of 390 nm, which is more than or equal to 0.3, with respect to acetonitrile solution having 0.1 mass% of concentration. Also, the adhesive, which is active energy ray-curable, has a cross-linking structure where (A) the (meth)acrylate ester polymers cross-link by using (B) the cross-linking agent, and contains an unreacted (C) active energy ray-curable component and (D) photo-polymerization initiator.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a pressure-sensitive adhesive sheet, a pressure-sensitive adhesive sheet,

The present invention relates to a pressure-sensitive adhesive sheet suitable for use in a display (display), a display obtained using the pressure-sensitive adhesive sheet, and a method for producing the display.

[0002] In recent years, car navigation systems have been often installed in automobiles. In a display body (display) of a car navigation system, a protective panel is provided on the surface side of the display body module. Normally, the protective panel is bonded to a display module or the like through a pressure-sensitive adhesive layer.

As a protective panel for a car navigation system, a plastic plate is often used, rather than a glass plate, from the viewpoint of safety. However, unlike a glass plate, a plastic plate generates outgas under high temperature and high humidity (wet heat) conditions, or transmits water vapor. As a result, blisters such as air bubbles, peeling, peeling, etc. may occur between the plastic plate and the pressure-sensitive adhesive layer.

Thus, Patent Document 1 and Patent Document 2 disclose a pressure-sensitive adhesive for a touch panel containing an acrylic polymer containing a predetermined monomer unit from the viewpoint of improving the resistance to moisture and heat. However, even when these pressure-sensitive adhesives were used, the resistance to blistering was not sufficient for the blister resistance under particularly high-temperature and high-humidity conditions.

As an adhesive sheet for a touch panel, Patent Document 3 discloses a pressure-sensitive adhesive sheet for a touch panel, which comprises a (meth) acrylic copolymer of a monomer containing a (meth) acrylic acid ester having an ultraviolet ray crosslinking site (benzophenone structure) Discloses an ultraviolet-crosslinkable pressure-sensitive adhesive sheet in which the storage elastic modulus before and after is specified. In such an ultraviolet crosslinkable pressure-sensitive adhesive sheet, the crosslinking reaction is advanced by irradiating ultraviolet light after adherend of an adherend to increase the cohesive force.

Japanese Patent Application Laid-Open No. 2013-1769 Japanese Patent Laid-Open Publication No. 2015-189852 Japanese Patent Laid-Open Publication No. 2011-184582

However, in the ultraviolet-crosslinkable pressure-sensitive adhesive sheet as described above, depending on the type of the protective panel, the ultraviolet-ray-curable pressure-sensitive adhesive does not cure sufficiently and blisters may be generated under high temperature and high humidity conditions.

It is an object of the present invention to provide a pressure-sensitive adhesive sheet, a display body and a method for producing the display body which are excellent in blister resistance even under severe high-temperature and high-humidity conditions.

In order to achieve the above object, firstly, the present invention provides a pressure sensitive adhesive sheet comprising one display body constituting member and a pressure sensitive adhesive layer for bonding other display body constituting members, wherein the one display body constituting member and the other display Wherein the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer comprises at least one of the pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer comprising at least one of the pressure- (D) having an absorbance at a wavelength of 390 nm of 0.3 or more in an acetonitrile solution having a concentration of 0.1% by mass, and a photopolymerization initiator (B) (A) is obtained from a sticky composition containing a cross-linking agent (B) and the cross-linking structure in which the (meth) acrylic acid ester polymer (1), wherein the adhesive sheet is an active energy ray-curable pressure-sensitive adhesive containing the actinic energy ray-curable component (C) and the photopolymerization initiator (D).

The term " made of a plastic plate " in the present invention does not mean " made of only a plastic plate ", but allows another layer or member to be laminated on a plastic plate.

In the pressure-sensitive adhesive sheet according to the invention (invention 1), at least one of the display member constituting member and the other display member constituting the pressure-sensitive adhesive layer to which the pressure-sensitive adhesive layer is adhered is a plastic plate, and even if the plastic plate contains an ultraviolet absorber , Excellent blister resistance under severe high temperature and high humidity conditions, and excellent anti-wet heat and whitening properties.

In the invention (Invention 1), it is preferable that the plastic plate contains an ultraviolet absorber (Invention 2).

In the above invention (invention 1 or 2), it is preferable that the gel fraction of the active energy ray-curable pressure-sensitive adhesive is 30% or more and 70% or less (invention 3).

In the above inventions (inventions 1 to 3), it is preferable to include two peeling sheets and the pressure-sensitive adhesive layer sandwiched between the peeling sheets so as to contact the peeling surfaces of the two peeling sheets 4).

Secondly, the present invention provides a display body having one display body constituting member, another display body constituting member, and a post-curing pressure-sensitive adhesive layer for bonding the one display body constituting member and the other display body constituting member to each other, Wherein at least one of the one display body constituting member and the other display body constituting member is made of a plastic plate and the cured pressure sensitive adhesive layer is formed by curing the pressure sensitive adhesive layer of the pressure sensitive adhesive sheet (inventions 1 to 4) Curing pressure-sensitive adhesive layer formed on the surface of the display body (invention 5).

In the invention (Invention 5), it is preferable that the gel fraction of the cured pressure-sensitive adhesive layer is not less than 40% and not more than 95% (invention 6).

In the above invention (inventions 5 and 6), it is preferable that the plastic plate has a thickness of 100 탆 and a vapor permeability of not more than 0.001 g / (m 2 · 24 h · 100 μm) measured according to JIS K7129 under conditions of 40 ° C. and 90% , 100 g / (m 2 · 24 h · 100 μm) or less (Invention 7).

In the above inventions (Invention 5 to 7), the vapor transmissivity of the one display member constituting member measured in accordance with JIS K7129 at a temperature of 40 DEG C and 90% RH is 0.001 g / (m < 2 & (M < 2 > 24h), and the vapor permeability of the other display component member measured at 40 DEG C and 90% RH in accordance with JIS K7129 is 0.001 g / 8).

Thirdly, the present invention is a method for manufacturing a pressure-sensitive adhesive sheet, comprising the steps of: preparing a laminate in which one display body constituting member and another display body constituting member are laminated via the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet (inventions 1 to 4) Layer is irradiated with an active energy ray to cure the pressure-sensitive adhesive layer to form a pressure-sensitive adhesive layer after curing (Invention 9).

In the invention (Invention 9), the active energy ray may be irradiated to the pressure-sensitive adhesive layer over a display member constituted of a plastic plate containing an ultraviolet absorber (Invention 10).

INDUSTRIAL APPLICABILITY The pressure-sensitive adhesive sheet and the display according to the present invention are excellent in resistance to blistering even under severe high-temperature and high-humidity conditions. Further, according to the method for producing a display body according to the present invention, a display body having excellent blister resistance can be produced even under severe high-temperature and high-humidity conditions.

1 is a sectional view of a pressure-sensitive adhesive sheet according to an embodiment of the present invention;
2 is a sectional view of a display body according to an embodiment of the present invention;

Hereinafter, an embodiment of the present invention will be described.

[Adhesive sheet]

The pressure-sensitive adhesive sheet according to the present embodiment is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer for bonding one display body constituting member and another display body constituting member. At least one of the one display body constituent member and the other display body constituent member is made of a plastic plate. The display body and the display body constituting member will be described later. The pressure-sensitive adhesive sheet according to the present embodiment is preferably formed by laminating a release sheet on one side or both sides of the pressure-sensitive adhesive layer.

Fig. 1 shows a specific configuration as an example of the pressure-sensitive adhesive sheet according to the present embodiment.

1, the pressure-sensitive adhesive sheet 1 according to one embodiment is formed by two sheets of release sheets 12a and 12b and two sheets of release sheets 12a and 12b in contact with the release surfaces of the two release sheets 12a and 12b, And a pressure-sensitive adhesive layer 11 sandwiched between the release sheets 12a and 12b. In the present specification, the release surface of the release sheet refers to a surface having release properties in the release sheet, and includes both the surface subjected to the release treatment and the surface exhibiting the release property without performing the release treatment.

1. Each member

1-1. The pressure-

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 11 is preferably a (meth) acrylic acid ester polymer (A) containing 10 mass% or more and 50 mass% or less of a monomer (hydroxyl group- , A crosslinking agent (B), an active energy ray-curable component (C), and a photopolymerization initiator (D) having an absorbance at a wavelength of 390 nm of 0.3 or more in an acetonitrile solution with a concentration of 0.1% (Meth) acrylic acid ester polymer (A) are crosslinked with each other via a crosslinking agent (B), and a crosslinked structure obtained by crosslinking the (meth) acrylic acid ester polymer (A) with an active energy ray curable component ) And a photopolymerization initiator (D). The active energy ray-curable pressure-sensitive adhesive is obtained by crosslinking (thermally crosslinking) the pressure-sensitive adhesive composition P and contains an unreacted active energy ray-curable component (C) and a photopolymerization initiator (D) Respectively. The active energy ray curable component (C) is polymerized and cured when the active energy ray is irradiated to the pressure-sensitive adhesive layer (11) at the time of using the pressure-sensitive adhesive sheet (after adherend is adhered). In the present specification, the term "(meth) acrylic acid" means both of acrylic acid and methacrylic acid. The same is true of other similar terms. The term " polymer " also includes the concept of " copolymer ".

It is preferable that the active energy ray in this embodiment has a substantial intensity of light emission in a wavelength range exceeding 365 nm. The wavelength range is preferably 380 to 450 nm, and more preferably 390 to 410 nm. Further, when the maximum light emission intensity at 365 nm or less (usually, the maximum peak intensity at 365 nm is nearest 100%), at least a part of the wavelength region has an intensity of 20% or more .

Since the pressure-sensitive adhesive layer 11 in the pressure-sensitive adhesive sheet 1 according to the present embodiment is relatively flexible at the stage before curing by irradiation with active energy rays, the pressure-sensitive adhesive sheet 1 is adhered to the display- , The pressure-sensitive adhesive layer (11) is easy to follow the step, and occurrence of gaps, floatation, and the like in the vicinity of the step is suppressed. Further, since the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 11 is crosslinked (thermally crosslinked) and has a certain degree of crosslinking density and a predetermined cohesive force, the pressure-sensitive adhesive layer 11 has a relatively high film strength. Therefore, for example, when the pressure-sensitive adhesive sheet is subjected to cutting or the like, the pressure-sensitive adhesive is adhered to the blade, or the pressure-sensitive adhesive layer 11 is prevented from being leaked from the pressure-sensitive adhesive layer 11 during storage.

In the case of using the pressure-sensitive adhesive sheet 1 according to the present embodiment, one pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 is used to bond one display element constituting member to another display element constituting member, The pressure sensitive adhesive layer 11 is cured by irradiating the pressure sensitive adhesive layer 11 with an active energy ray via another display material constituting member so as to form a pressure sensitive adhesive layer after the curing (in the pressure sensitive adhesive layer 11 ' ).

The term " after curing " of the cured pressure-sensitive adhesive layer in the present embodiment refers to a state in which the increase in the gel fraction of the pressure-sensitive adhesive by irradiation with active energy rays is less than 5 points.

Here, when one of the display body constituting members and / or the other display body constituting members (particularly the plastic plate) contains an ultraviolet absorber (typically, the light transmittance at a wavelength of 360 nm is 20% or less and the wavelength at 390 nm A light transmittance of 10% or more and a light transmittance of a wavelength of 390 nm is larger than a light transmittance of a wavelength of 360 nm), when a conventional photopolymerization initiator such as 1-hydroxycyclohexyl phenyl ketone is used , An active energy ray having a wavelength (around 360 nm) for opening the photopolymerization initiator is irradiated to the pressure sensitive adhesive layer through the one display body constituting member or the other display body constituting member, Absorbed in the ultraviolet absorber in the member, and cleavage of the photopolymerization initiator is inhibited. As a result, the curing reaction of the active energy ray-curable component does not proceed well and the curing of the pressure-sensitive adhesive layer becomes insufficient. Then, outgas is generated under high temperature and high humidity conditions, and blisters such as bubbles, lifting and peeling are generated at the interface between the plastic plate that permeates water vapor and the cured pressure-sensitive adhesive layer.

In contrast, the pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 according to the present embodiment contains a photopolymerization initiator (D) having an absorbance at a wavelength of 390 nm of 0.3 or more in an acetonitrile solution having a concentration of 0.1% do. In this case, even when the active energy ray is irradiated to the pressure-sensitive adhesive layer 11 via the display body constituting member containing the ultraviolet absorber, an active energy ray having a wavelength (near 390 nm) for opening the photopolymerization initiator (D) Is hardly absorbed by the ultraviolet absorber in the display member constituting member, and the photopolymerization initiator (D) is cleared without problems. As a result, the curing reaction of the active energy ray-curable component (C) proceeds well and the pressure-sensitive adhesive layer (11) is sufficiently cured, so that the cohesive force of the resulting cured pressure-sensitive adhesive layer is improved. Further, in the pressure-sensitive adhesive sheet 1 according to the present embodiment, the (meth) acrylic acid ester polymer (A) contains a large amount of the hydroxyl group-containing monomer as the monomer constituting the polymer. As a result, the glass transition temperature (Tg) of the (meth) acrylic acid ester polymer (A) becomes relatively high. By these actions, even when the laminate (display body) including the plastic plate is left under the strict high temperature and high humidity conditions, for example, under the conditions of 85 DEG C and 85% RH for 1000 hours, the display body constituting member and the cured pressure- The occurrence of blisters at the interface between the barrier layer and the barrier layer is suppressed.

In the pressure-sensitive adhesive sheet 1 according to the present embodiment, the (meth) acrylic acid ester polymer (A) contains a large amount of the hydroxyl group-containing monomer as the monomer constituting the polymer, 11), and the pressure-sensitive adhesive layer after curing exhibit excellent hydrophilicity. Thus, even when the display body 2 is placed under the high temperature and high humidity conditions, the post-curing pressure-sensitive adhesive layer having excellent hydrophilicity can prevent the moisture permeating into the pressure-sensitive adhesive layer after curing under the high temperature and high humidity conditions, It is presumed that it becomes easier to get out of the apparatus. Therefore, even when the plastic plate permeates water vapor under high-temperature and high-humidity conditions, it is accompanied with the effect of the above-mentioned high glass transition temperature (Tg), resulting in lifting between the plastic plate and the cured adhesive layer due to the water vapor . Further, since moisture is easily released from the pressure-sensitive adhesive layer after curing, condensation of the moisture in the pressure-sensitive adhesive layer after curing is also less likely to occur, thereby suppressing whitening of the pressure-sensitive adhesive layer after curing.

As described above, in the pressure-sensitive adhesive sheet 1 according to the present embodiment, even if at least one of the display member constituting members and the other display member constituting members is a plastic plate and the plastic plate contains an ultraviolet absorber, Excellent blister resistance under high temperature and high humidity conditions, and excellent anti-wet heat and whitening properties.

(1) Component

(1-1) Synthesis of (meth) acrylic acid ester polymer (A)

The (meth) acrylic acid ester polymer (A) contains 10 mass% or more, preferably 20 mass% or more, particularly preferably 25 mass% or more of the hydroxyl group-containing monomer as the monomer constituting the polymer , And more preferably 30% by mass or more in consideration of anti-wet heat whitening. As a result, as described above, the pressure-sensitive adhesive sheet 1 has excellent resistance to blistering and excellent anti-wet heat resistance. Further, compatibility with the active energy ray-curable component (C) becomes good, and the transparency of the resulting cured pressure-sensitive adhesive layer is also improved.

On the other hand, the (meth) acrylic acid ester polymer (A) contains 60 mass% or less, preferably 50 mass% or less, and particularly preferably 40 mass% or less of the hydroxyl group-containing monomer as the monomer constituting the polymer . This makes it possible to sufficiently secure the content of monomers other than the hydroxyl group-containing monomer, and the resulting pressure-sensitive adhesive becomes more excellent in tackiness.

Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (Meth) acrylate such as 3-hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate. Among them, 2-hydroxyethyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate are preferable from the viewpoint of resistance to blistering and anti-wet heat. Particularly preferred are 2-hydroxyethyl acrylate and methacrylic acid 2-hydroxyethyl is preferred. These may be used alone or in combination of two or more.

The (meth) acrylic acid ester polymer (A) preferably contains a (meth) acrylic acid alkyl ester as a monomer unit constituting the polymer. As a result, good tackiness can be exhibited. The alkyl group may be straight-chain or branched.

As the (meth) acrylic acid alkyl ester, a (meth) acrylic acid alkyl ester having 1 to 20 carbon atoms in the alkyl group is preferable from the viewpoint of 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, n-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl Stearyl (meth) acrylate, stearyl (meth) acrylate, and the like. These may be used alone or in combination of two or more.

Of these, (meth) acrylic acid alkyl esters having an alkyl group of 2 to 12 carbon atoms are more preferable from the viewpoint of resistance to blistering, and alkyl acrylate having an alkyl group of 5 to 10 carbon atoms Esters are particularly preferred. Specific examples include butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and isooctyl (meth) acrylate, and 2-ethylhexyl acrylate and isooctyl acrylate are more preferred. These may be used alone or in combination of two or more.

The (meth) acrylic acid ester polymer (A) preferably contains a (meth) acrylic acid alkyl ester as a lower limit of 10 mass% or more, more preferably 15 mass% or more as a monomer unit constituting the polymer , Particularly preferably 20 mass% or more, and more preferably 30 mass% or more. If the lower limit of the content of the (meth) acrylic acid alkyl ester is above, the (meth) acrylic acid ester polymer (A) can exhibit favorable tackiness. The (meth) acrylic acid ester polymer (A) preferably contains 90 mass% or less of the (meth) acrylic acid alkyl ester as the upper limit of the monomer unit constituting the polymer, more preferably 85 mass% or less , And more preferably 80 mass% or less. If the upper limit of the content of the (meth) acrylic acid alkyl ester is as described above, another monomer component such as a hydroxyl group-containing monomer in the (meth) acrylic acid ester polymer (A)

The (meth) acrylic acid ester polymer (A) preferably contains a monomer having an alicyclic structure (monomer containing an alicyclic structure) as a monomer unit constituting the polymer. Since the alicyclic structure-containing monomer is bulky, it is presumed that the presence of the alicyclic structure in the polymer broadens the intervals between the polymers, and the obtained pressure-sensitive adhesive can be made excellent in flexibility. As a result, the pressure sensitive adhesive is excellent in step traceability.

The carbon ring of the alicyclic structure in the alicyclic structure-containing monomer may have a saturated structure or may have an unsaturated bond in a part thereof. The alicyclic structure may be a monocyclic alicyclic structure or a polycyclic alicyclic structure such as a bicyclic or tricyclic ring. The alicyclic structure is preferably a polycyclic alicyclic structure (polycyclic structure) from the viewpoint of making the distance between the obtained (meth) acrylic acid ester polymer (A) appropriate and giving higher stress relaxation property to the pressure- Do. In consideration of the compatibility of the (meth) acrylic acid ester polymer (A) with other components, the polycyclic structure is particularly preferably a bicyclic to tetracyclic ring. In addition, from the viewpoint of imparting stress relaxation property as described above, the number of carbon atoms of the alicyclic structure (the total number of carbon atoms in the part forming the ring, when plural rings are present independently, refers to the total number of carbon atoms) , Usually 5 or more, and particularly preferably 7 or more. On the other hand, the upper limit of the carbon number of the alicyclic structure is not particularly limited, but from the viewpoint of compatibility as described above, it is preferably 15 or less, and particularly preferably 10 or less.

Specific examples of the alicyclic structure-containing monomer include cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, adamantyl (meth) acrylate, isobornyl (meth) acrylate, dicyclo (Dicyclopentanyl (meth) acrylate dicyclopentanyl (the number of carbon atoms in the alicyclic structure is 10), (meth) acrylate, and the like) exhibiting better blister resistance, Adamantyl acrylate (the number of carbon atoms of the alicyclic structure is 10) or isobornyl (meth) acrylate (the number of carbon atoms of the alicyclic structure is 7), and isobornyl (meth) acrylate is particularly preferable. These may be used singly or in combination of two or more kinds.

The (meth) acrylic acid ester polymer (A) preferably contains 3% by mass or more, more preferably 6% by mass or more, and more preferably 9% by mass or more of the monomer unit constituting the polymer, Or more. The content of the alicyclic structure-containing monomer is preferably 30% by mass or less, more preferably 20% by mass or less, from the viewpoint of ensuring the blending amount of the other components in the (meth) acrylic acid ester polymer (A) By mass, and particularly preferably 15% by mass or less. When the proportion of the alicyclic structure-containing monomer is in the above-mentioned range, the pressure-sensitive adhesive obtained is more excellent in step-wise followability and more excellent in adhesion to plastic.

It is also preferable that the (meth) acrylic acid ester polymer (A) contains a monomer having a nitrogen-containing heterocyclic ring and a (meth) acryloyl group as a monomer unit constituting the polymer. By presenting such a monomer as a constituent unit in a polymer, it is possible to impart a predetermined polarity to a pressure-sensitive adhesive and to make an adherend having a certain degree of polarity such as glass excellent in affinity, It may have a proper rigidity.

Examples of the monomer having a nitrogen-containing heterocyclic ring and a (meth) acryloyl group include N- (meth) acryloylmorpholine, N- (meth) acryloylpyrrolidone, N- (Meth) acryloylpyrrolidone, N- (meth) acryloyl aziridine, aziridinyl ethyl (meth) acrylate, and the like. Of these, N - (meth) acryloylmorpholines are preferred, and N-acryloylmorpholines are particularly preferred. These may be used singly or in combination of two or more kinds.

Further, in the present embodiment, when nitrogen atom-containing monomers other than the monomer having a nitrogen-containing heterocyclic ring and a (meth) acryloyl group are used, the cohesive force of the resulting pressure-sensitive adhesive does not become too high, There is a possibility that the adhesive strength is excessively lowered or the blister resistance can not be obtained. Therefore, in the present embodiment, it is preferable not to use a nitrogen atom-containing monomer other than the monomer having a nitrogen-containing heterocyclic ring and a (meth) acryloyl group.

When the (meth) acrylic acid ester polymer (A) contains a nitrogen atom-containing monomer as the monomer unit constituting the polymer, it preferably contains the nitrogen atom-containing monomer in an amount of 0.5 mass% or more, more preferably 1 mass% And particularly preferably 3% by mass or more. The (meth) acrylic acid ester polymer (A) preferably contains 20 mass% or less of the nitrogen atom-containing monomer as the monomer unit constituting the polymer, particularly preferably 15 mass% or less. By mass or less. When the content of the nitrogen atom-containing monomer is within the above-mentioned range, the obtained pressure-sensitive adhesive can sufficiently exert an excellent adhesive force to glass.

The (meth) acrylic acid ester polymer (A) may contain other monomers as monomer units constituting the polymer, if desired. On the other hand, it is also preferable that the (meth) acrylic acid ester polymer (A) does not contain a monomer containing a carboxyl group as a monomer unit constituting the polymer. Since the carboxyl group is an acid component, it is preferable that a transparent substrate such as a transparent conductive film such as tin-doped indium oxide (ITO) or a metal film (Corrosion, change in resistance value, and the like) due to acid can be suppressed even in the presence of an acid.

Here, the expression " not containing a carboxyl group-containing monomer " means that the monomer does not substantially contain a carboxyl group-containing monomer, and includes not only a carboxyl group-containing monomer but also a carboxyl group- Containing monomer to such an extent that corrosion does not occur. Concretely, a monomer containing a carboxyl group-containing monomer in an amount of 0.1% by mass or less, preferably 0.01% by mass or less, more preferably 0.001% by mass or less, as a monomer unit in the (meth) acrylic acid ester polymer (A) .

The (meth) acrylic acid ester polymer (A) is preferably a linear polymer. By virtue of the linear polymer, entanglement of the molecular chains is apt to occur and an improvement in cohesive force can be expected, so that a pressure-sensitive adhesive excellent in blister resistance can be obtained.

The (meth) acrylic acid ester polymer (A) is preferably a solution polymer obtained by a solution polymerization method. As a solution polymer, a polymer having a high molecular weight is easily obtained, and a resulting pressure-sensitive adhesive can be expected to have an improved cohesive force, and thus has better blister resistance.

The polymerization of the (meth) acrylic acid ester polymer (A) may be a random copolymer or a block copolymer.

The weight average molecular weight of the (meth) acrylic acid ester polymer (A) is preferably 200,000 or more as the lower limit value, more preferably 300,000 or more, particularly preferably 400,000 or more, and more preferably 500,000 or more. If the lower limit of the weight-average molecular weight of the (meth) acrylic acid ester polymer (A) is higher than the above-mentioned range, the resultant pressure-sensitive adhesive has better blister resistance.

The upper limit of the weight average molecular weight of the (meth) acrylic acid ester polymer (A) is preferably not more than 2,000,000, particularly preferably not more than 1.5 million, more preferably not more than 1,000,000. When the upper limit of the weight-average molecular weight of the (meth) acrylic acid ester polymer (A) is not more than the above value, the resulting pressure sensitive adhesive exhibits better step traceability. In the present specification, the weight average molecular weight is a value in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method.

The glass transition temperature (Tg) of the (meth) acrylic acid ester polymer (A) is preferably -100 占 폚 or higher as the lower limit value, particularly preferably -60 占 폚 or higher, and more preferably -40 占 폚 or higher. The upper limit of the glass transition temperature (Tg) is preferably 0 DEG C or lower, particularly preferably -5 DEG C or lower, and more preferably -10 DEG C or lower. When the glass transition temperature (Tg) of the (meth) acrylic acid ester polymer (A) is in the above-mentioned range, the resulting pressure-sensitive adhesive has satisfactory cohesion and flexibility and has sufficient cohesive strength and exhibits excellent blister resistance and step- .

In the adhesive composition P, the (meth) acrylic acid ester polymer (A) may be used singly or in combination of two or more kinds.

The content of the (meth) acrylic acid ester polymer (A) in the sticky composition P according to the present embodiment is preferably 50% by mass or more, particularly preferably 60% by mass or more as the lower limit value, more preferably 70% desirable. The lower limit of the content of the (meth) acrylic acid ester polymer (A) makes the adhesive force of the obtained pressure sensitive adhesive better. The upper limit of the content of the (meth) acrylic acid ester polymer (A) is preferably 99 mass% or less, more preferably 97 mass% or less, particularly preferably 95 mass% or less, and more preferably 93 mass% desirable. The content of other components such as the crosslinking agent (B), the active energy ray-curable component (C) and the photopolymerization initiator (D) is ensured by the above-mentioned upper limit value of the content of the (meth) acrylic acid ester polymer (A) The blister property is more excellent.

(1-2) Crosslinking agent (B)

The cross-linking agent (B) can crosslink the (meth) acrylic acid ester polymer (A) by heating the adhesive composition P to favorably form a three-dimensional network structure. As a result, the cohesive force of the resulting pressure-sensitive adhesive is further improved, and the blister resistance is further improved.

The crosslinking agent (B) is not particularly limited as long as it can react with the reactive functional group possessed by the (meth) acrylic acid ester polymer (A). Examples thereof include isocyanate crosslinking agents, epoxy crosslinking agents, amine crosslinking agents, melamine crosslinking agents, aziridine crosslinking agents, Hydrazine type crosslinking agents, aldehyde type crosslinking agents, oxazoline type crosslinking agents, metal alkoxide type crosslinking agents, metal chelate type crosslinking agents, metal salt type crosslinking agents and ammonium salt type crosslinking agents. Here, as described above, the (meth) acrylic acid ester polymer (A) preferably contains an isocyanate-based crosslinking agent having excellent reactivity with a hydroxyl group as the crosslinking agent (B) in order to contain a hydroxyl group- containing monomer as a constituent monomer unit . The crosslinking agent (B) may be used alone or in combination of two or more.

The isocyanate crosslinking agent includes at least a polyisocyanate compound. Examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane di An alicyclic polyisocyanate such as isocyanate and the like, and an adduct which is a reaction product of a burette, isocyanurate and a low molecular active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylol propane, And the like. Among them, trimethylolpropane-modified aromatic polyisocyanates, especially trimethylolpropane-modified tolylene diisocyanate and trimethylolpropane-modified xylylene diisocyanate are preferable from the viewpoint of reactivity with hydroxyl groups.

The content of the crosslinking agent (B) in the adhesive composition P is preferably 0.01 parts by mass or more, particularly preferably 0.05 parts by mass or more, and more preferably 0.1 parts by mass or more per 100 parts by mass of the (meth) acrylic acid ester polymer (A) Is more preferable. The content is preferably 3 parts by mass or less, particularly preferably 2 parts by mass or less, more preferably 1 part by mass or less. When the content of the cross-linking agent (B) is in the above-mentioned range, the degree of cross-linking becomes appropriate, and the resultant pressure-sensitive adhesive has better blister resistance.

(1-3) Active energy ray-curable component (C)

The pressure-sensitive adhesive obtained by crosslinking (cross-linking) the pressure-sensitive adhesive composition P by the pressure-sensitive adhesive composition P containing the active energy ray-curable component (C) becomes a pressure- This pressure sensitive adhesive is obtained by curing the active energy ray curable component (C) with each other by curing by irradiation with active energy rays after the adherend is attached, and the polymerized active energy ray curable component (C) It is presumed to be entangled with the crosslinked structure (three-dimensional network structure) of A). Such a pressure-sensitive adhesive having a higher-order structure has a higher cohesive strength and exhibits a higher film strength, resulting in better blister resistance.

The active energy ray-curable component (C) is not particularly limited as long as it is cured by irradiation with an active energy ray and is capable of obtaining the above effect, and may be any of monomers, oligomers or polymers, or a mixture thereof. Among them, polyfunctional acrylate-based monomers excellent in compatibility with the (meth) acrylic acid ester polymer (A) and the like are preferable.

Examples of polyfunctional acrylate monomers include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (Meth) acrylate, neopentyl glycol adipate di (meth) acrylate, hydroxypivalic neopentyl glycol di (meth) acrylate, dicyclopentanyl di (meth) acrylate, caprolactone modified dicyclopentenyl Di (acryloxyethyl) isocyanurate, allyl cyclohexyl di (meth) acrylate, ethoxylated bisphenol A diacrylate, 9,9-di (meth) acrylate, Bifunctional types such as bis [4- (2-acryloyloxyethoxy) phenyl] fluorene; (Meth) acrylate such as trimethylolpropane tri (meth) acrylate, dipentaerythritol tri (meth) acrylate, propionic acid modified dipentaerythritol tri (meth) acrylate, pentaerythritol tri Trifunctional types such as tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, and? -Caprolactone modified tris- (2- (meth) acryloxyethyl) isocyanurate; Tetrafunctional types such as diglycerin tetra (meth) acrylate and pentaerythritol tetra (meth) acrylate; Pentafunctional type such as propionic acid-modified dipentaerythritol penta (meth) acrylate; And hexafunctional types such as dipentaerythritol hexa (meth) acrylate and caprolactone-modified dipentaerythritol hexa (meth) acrylate. Among the above, from the viewpoints of blister resistance and step traceability under high temperature and high humidity conditions of the pressure-sensitive adhesive to be obtained, it is preferable to use di (acryloxyethyl) isocyanurate, tris (acryloxyethyl) isocyanurate,? -Caprolactone- - (2- (meth) acryloxyethyl) isocyanurate and the like are preferable, and a polyfunctional acrylate monomer containing an isocyanurate structure in the molecule is preferable, and a trifunctional or more functional isocyanurate structure Is more preferable, and ε-caprolactone-modified tris- (2- (meth) acryloxyethyl) isocyanurate is particularly preferable. These may be used singly or in combination of two or more kinds. From the viewpoint of compatibility with the (meth) acrylic acid ester polymer (A), the polyfunctional acrylate monomer preferably has a molecular weight of less than 1,000.

As the active energy ray-curable component (C), an active energy ray-curable acrylate oligomer may be used. Examples of such acrylate oligomers include polyester acrylate, epoxy acrylate, urethane acrylate, polyether acrylate, polybutadiene acrylate, and silicone acrylate.

The weight average molecular weight of the acrylate oligomer is preferably 50,000 or less, more preferably 1,000 to 50,000, and even more preferably 3,000 to 40,000. These acrylate oligomers may be used singly or in combination of two or more.

As the active energy ray curable component (C), an acryl acrylate polymer having a group having a (meth) acryloyl group introduced into its side chain may also be used. Such an acryl acrylate polymer may be obtained by copolymerizing a (meth) acrylic acid ester with a monomer having a crosslinkable functional group in the molecule and adding a (meth) acryloyl group to a part of the crosslinkable functional group of the copolymer And a compound having a group capable of reacting with a crosslinkable functional group.

The weight average molecular weight of the adduct acrylate-based polymer is preferably from 50,000 to 900,000, and particularly preferably from 100,000 to 500,000.

The active energy ray-curable component (C) may be selected from among the above-mentioned polyfunctional acrylate-based monomer, acrylate-based oligomer and adduct acrylate-based polymer, or a combination of two or more thereof And may be used in combination with other active energy ray curable components.

The content of the active energy ray-curable component (C) in the adhesive composition P is preferably within a range from 100 parts by mass to 100 parts by mass of the (meth) acrylic acid ester polymer (A) from the viewpoint of improving the cohesive force of the obtained pressure- The lower limit value is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and particularly preferably 5 parts by mass or more. On the other hand, the content is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, as an upper limit value from the viewpoint of preventing phase separation of the active energy ray-curable component (C) from the (meth) acrylic acid ester polymer And further preferably 10 parts by mass or less, from the viewpoint of better initial step following property.

(1-4) Photopolymerization initiator (D)

The photopolymerization initiator (D) in the present embodiment has an absorbance at a wavelength of 390 nm of 0.3 or more in an acetonitrile solution having a concentration of 0.1% by mass. Since the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 11 contains such a photopolymerization initiator (D), even when the active energy ray is irradiated to the pressure-sensitive adhesive layer (11) via the display body constituting member containing the ultraviolet absorber, The pressure-sensitive adhesive layer after the curing (D) is removed without problems and the pressure-sensitive adhesive layer 11 (active energy ray-curable component (C)) is cured well.

In view of the above, the photopolymerization initiator (D) preferably has an absorbance at a wavelength of 390 nm of 0.5 or more, particularly preferably 1.0 or more. The upper limit of the absorbance is not particularly limited, but is usually preferably 2.5 or less, and particularly preferably 2.0 or less. If the absorbance exceeds 2.5, the curing reaction of the active energy ray-curable component (C) by the photopolymerization initiator (D) proceeds by the ambient light such as a fluorescent lamp during formation or storage of the pressure sensitive adhesive sheet, There is a case where the step following property in the case of the step difference is lowered. Here, the method of measuring the absorbance of the photopolymerization initiator (D) is as shown in the following test examples.

The photopolymerization initiator (D) preferably has an absorption maximum wavelength of an absorbance at a wavelength of 200 to 500 nm in an acetonitrile solution having a concentration of 0.1% by mass of 350 nm or more, particularly preferably 370 nm or more , And more preferably 380 nm or more. When there is a plurality of absorption maximum wavelengths of absorbance at a wavelength of 200 to 500 nm, at least one absorption maximum wavelength should be within the above range. This makes it possible to improve the curability of the pressure-sensitive adhesive layer 11 (active energy ray-curable component (C)) when the active energy ray is irradiated to the pressure-sensitive adhesive layer (11) via the display body constituting member containing the ultraviolet absorber , And my blistering property is more excellent. On the other hand, the upper limit value of the maximum absorption maximum wavelength is not particularly limited, but is preferably 450 nm or less, particularly preferably 410 nm or less, from the viewpoint of preventing the progress of the curing reaction when the pressure-sensitive adhesive layer 11 is stored in ambient light , And more preferably 405 nm or less.

Examples of such a photopolymerization initiator (D) include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (4-cyclopentadienyl) bis [2,6-difluoro-3- (1-pyryl) phenyl] titanium (IV). These may be used alone or in combination of two or more.

(1-5) Silane coupling agent (E)

The sticky composition P preferably further contains a silane coupling agent (E). Thus, even if the adherend is a plastic plate or a glass member, adhesion with the adherend improves, and blister resistance is further improved.

As the silane coupling agent (E), an organosilicon compound having at least one alkoxysilyl group in the molecule is preferred because it has good compatibility with the (meth) acrylic acid ester polymer (A) and has optical transparency.

Examples of such a silane coupling agent (E) include a polymerizable unsaturated group-containing silicon compound such as vinyltrimethoxysilane, vinyltriethoxysilane, and methacryloxypropyltrimethoxysilane, 3-glycidoxypropyl tri A silicon compound having an epoxy structure such as methoxysilane and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3 Mercapto group-containing silicon compounds such as mercaptopropyldimethoxymethylsilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- Ethyl) -3-aminopropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, or a mixture of at least one of these with methyltriethoxysilane, ethyl Triethoxysilane, methyltrimethoxysilane And condensates with an alkyl group-containing silicon compound such as silane, ethyltrimethoxysilane, and the like. These may be used singly or in combination of two or more kinds.

The content of the silane coupling agent (E) in the sticky composition P is preferably 0.01 parts by mass or more, particularly preferably 0.05 parts by mass or more, and more preferably 0.1 parts by mass or more per 100 parts by mass of the (meth) acrylic acid ester polymer (A) Or more. The content is preferably 1 part by mass or less, particularly preferably 0.5 parts by mass or less, and more preferably 0.3 parts by mass or less.

(1-6) Various additives

Various additives commonly used in acrylic pressure sensitive adhesives such as an ultraviolet absorber, an antistatic agent, a tackifier, an antioxidant, a light stabilizer, a softening agent, a filler, a refractive index adjuster and an antirust agent can be added to the adhesive composition P have. It is also assumed that the polymerization solvent or diluting solvent to be described later is not included in the additive constituting the adhesive composition P.

(2) Preparation of sticky composition

The sticky composition P is obtained by preparing a (meth) acrylic acid ester polymer (A) and reacting the resulting (meth) acrylic acid ester polymer (A), the crosslinking agent (B), the active energy ray curable component (C) ) And, optionally, adding a silane coupling agent (E) and an additive.

The (meth) acrylic acid ester polymer (A) can be produced by polymerizing a mixture of monomers constituting the polymer by a conventional radical polymerization method. The polymerization of the (meth) acrylic acid ester polymer (A) can be carried out by a solution polymerization method or the like using a polymerization initiator, if desired. As the polymerization solvent, for example, ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone and the like may be used.

Examples of the polymerization initiator include an azo compound, an organic peroxide, and the like, and two or more types may be used in combination. Examples of the azo compound include azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 1,1'-azobis (cyclohexane 1-carbonyl Azobis (2,4-dimethyl-4-methoxy valeronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile) Azobis (2-methylpropionate), 4,4'-azobis (4-cyanovaleric acid), 2,2'-azobis (2-hydroxymethylpropionitrile) Azobis [2- (2-imidazolin-2-yl) propane] and the like.

Examples of the organic peroxide include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di (2-ethoxyethyl) peroxydicarbonate , t-butyl peroxyneodecanoate, t-butyl peroxypivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, and diacetyl peroxide.

In the polymerization step, a weight average molecular weight of the obtained polymer can be controlled by blending a chain transfer agent such as 2-mercaptoethanol.

(B), an active energy ray-curable component (C), a photopolymerization initiator (D) and, if desired, a (meth) acrylic acid ester polymer (A) A silane coupling agent (E) and an additive are added, and the mixture is thoroughly mixed to obtain a sticky composition P (coating solution) diluted with a solvent. In the case where precipitation occurs when any one of the above components is used in a solid phase or when it is mixed with other components in a non-diluted state, the component is solely dissolved or diluted in advance in a diluting solvent , And then mixed with other components.

Examples of the diluting solvent include aliphatic hydrocarbons such as hexane, heptane and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, alcohols such as methanol, ethanol, propanol, Propanol and the like; ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone and cyclohexanone; esters such as ethyl acetate and butyl acetate; and cellosolve solvents such as ethyl cellosolve Is used.

The concentration and viscosity of the coating solution thus prepared are not particularly limited and may be appropriately selected according to the circumstances. For example, it is diluted such that the concentration of the sticky composition P is 10 to 60 mass%. In order to obtain the coating solution, the addition of a diluting solvent and the like is not a necessary condition, and a diluting solvent may not be added if the viscosity of the adhesive composition P is such as to be a coating. In this case, the adhesive composition P is a coating solution containing a polymerization solvent of the (meth) acrylic acid ester polymer (A) as it is as a diluting solvent.

(3) Formation of a pressure-sensitive adhesive layer

The pressure-sensitive adhesive layer (11) is formed by thermally crosslinking the pressure-sensitive adhesive composition (P). That is, the crosslinking of the adhesive composition P is carried out by a heat treatment. This heat treatment can also serve as a drying treatment after application of the adhesive composition P.

The heating temperature for the heat treatment is preferably 50 to 150 占 폚, particularly preferably 70 to 120 占 폚. The heating time is preferably 10 seconds to 10 minutes, particularly preferably 50 seconds to 2 minutes. It is particularly preferable to provide a curing period of about 1 to 2 weeks at room temperature (for example, 23 DEG C, 50% RH) after the heat treatment.

The (meth) acrylic acid ester polymer (A) is favorably crosslinked through the crosslinking agent (B) by the above heat treatment (and curing).

(4) Thickness of the pressure-sensitive adhesive layer

The thickness of the pressure-sensitive adhesive layer 11 (measured in accordance with JIS K7130) is preferably 20 占 퐉 or more, more preferably 25 占 퐉 or more, particularly preferably 30 占 퐉 or more, more preferably 50 占 퐉 or more Do. The upper limit of the thickness of the pressure-sensitive adhesive layer 11 is preferably 500 탆 or less, more preferably 400 탆 or less, and particularly preferably 300 탆 or less. When the thickness of the pressure-sensitive adhesive layer 11 is in the above-mentioned range, the blister resistance is more excellent. Further, if the lower limit of the thickness of the pressure-sensitive adhesive layer 11 is above the above-described range, it is also superior to the anti-wet heat treatment.

1-2. Peeling sheet

The release sheets 12a and 12b protect the pressure-sensitive adhesive layer 11 by the use of the pressure-sensitive adhesive sheet 1 and are peeled off when the pressure-sensitive adhesive sheet 1 (pressure-sensitive adhesive layer 11) is used. In the pressure-sensitive adhesive sheet 1 according to the present embodiment, one or both of the release sheets 12a and 12b are not necessarily required.

Examples of the release sheets 12a and 12b include 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, (Meth) acrylic acid copolymer film, an ethylene / (meth) acrylic acid ester copolymer film, a polystyrene film, a poly (ethylene terephthalate) film, a polybutylene terephthalate film, a polyurethane film, an ethylene vinyl acetate film, an ionomer resin film, A carbon film, a polyimide film, a fluororesin film, or the like is used. These crosslinked films are also used. Further, these laminated films may be used.

It is preferable that a peeling treatment is performed on the peeling surface of the peeling sheets 12a and 12b (in particular, the surface in contact with the peeling layer 11). Examples of the releasing agent used in the peeling treatment include alkyd-based, silicone-based, fluorine-based, unsaturated polyester-based, polyolefin-based, and wax-based releasing agents. It is also preferable that one of the release sheets 12a and 12b is a heavy-duty release sheet having a large stripping force and the other release sheet is a light-leakage release sheet having a small stripping force.

The thickness of the release sheets 12a, 12b is not particularly limited, but is usually about 20 to 150 mu m.

2. Production of adhesive sheet

In one production example of the adhesive sheet 1, the application liquid of the adhesive composition P is applied to the release surface of one release sheet 12a (or 12b), and the adhesive composition P is crosslinked (heat crosslinked) After the application layer is formed, the release surface of the other release sheet 12b (or 12a) is superimposed on the application layer. When the curing period is required, the curing period is set so that the coating layer becomes the pressure-sensitive adhesive layer 11 when the curing period is unnecessary. Thus, the pressure-sensitive adhesive sheet (1) is obtained. The conditions of the heat treatment and curing are as described above.

In another production example of the adhesive sheet 1, the application solution of the adhesive composition P is applied to the release surface of one release sheet 12a, and the adhesive composition P is crosslinked (heat crosslinked) by heat treatment, To obtain a release sheet 12a with a coating layer. Further, the application solution of the adhesive composition P is applied to the release surface of the other release sheet 12b, and the adhesive composition P is crosslinked (heat-crosslinked) by heat treatment to form a coating layer, The release sheet 12b is obtained. Then, the peeling sheet 12a with a coating layer and the peeling sheet 12b with a coating layer are bonded so that both coating layers are in contact with each other. When the curing period is required, the curing period is provided, and when the curing period is unnecessary, the above-mentioned laminated coating layer becomes the pressure-sensitive adhesive layer (11). Thus, the pressure-sensitive adhesive sheet (1) is obtained. According to this manufacturing method, even if the pressure-sensitive adhesive layer 11 is thick, it can be manufactured stably.

As a method of applying the coating solution 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 and the like can be used.

3. Properties of Adhesive Sheet

(1) Vapor permeability

In the pressure-sensitive adhesive sheet 1 according to the present embodiment, the pressure-sensitive adhesive layer formed by curing the pressure-sensitive adhesive layer 11 having a thickness of 100 μm by irradiation of active energy rays is sandwiched between two pieces of Tetralon mesh # The water vapor permeability of the cured pressure-sensitive adhesive layer measured in accordance with JIS K7129 under the conditions of 40 占 폚 and 90% RH is preferably 108 g / (m2 占 24h 占 100 占 퐉) or more and preferably 110g / (m2 占 24h 占 100 占 퐉) And particularly preferably at least 115 g / (m 2 · 24 h · 100 μm) or more. The water vapor permeability is preferably 200 g / (m 2 · 24 h · 100 μm) or less, more preferably 180 g / (m 2 · 24 h · 100 μm) or less and more preferably 160 g / (m 2 · 24 h · 100 μm) Particularly preferably 150 g / (m 2 · 24 h · 100 μm) or less. The test method for the water vapor transmission rate is as shown in the following test examples.

In the pressure-sensitive adhesive sheet 1 according to the present embodiment, since the water vapor transmission rate of the pressure-sensitive adhesive layer after curing is in the above-mentioned range, the blister resistance is more excellent when the display body is placed under high temperature and high humidity conditions, After being placed under high temperature and high humidity conditions, when the pressure is returned to normal temperature and normal humidity, whitening of the pressure-sensitive adhesive layer after curing is more effectively suppressed.

(2) Gel fraction

(2-1) Gel fraction before irradiation with active energy ray

The gel fraction of the pressure-sensitive adhesive (prior to irradiation with active energy rays) constituting the pressure-sensitive adhesive layer 11 is preferably 30% or more, more preferably 40% or more, and particularly preferably 50% or more as the lower limit value. When the lower limit value of the gel fraction of the pressure-sensitive adhesive before the active energy ray irradiation is higher than the above value, the cohesive force of the pressure-sensitive adhesive layer 11 is improved and the pressure sensitive adhesive is adhered to the blade when the pressure-sensitive adhesive sheet 1 is cut, 11) is effectively suppressed. The gel fraction of the pressure-sensitive adhesive prior to irradiation with active energy rays is preferably 70% or less, more preferably 65% or less, and most preferably 60% or less as the upper limit value. If the upper limit of the gel fraction of the pressure-sensitive adhesive before the active energy ray irradiation is above, the pressure-sensitive adhesive does not become too hard, and the initial step-wise followability becomes better. The method for measuring the gel fraction of the pressure-sensitive adhesive (before irradiation with active energy ray) is as shown in the following test examples.

(2-2) Gel fraction after irradiation with active energy ray

The gel fraction of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer after curing after the pressure-sensitive adhesive layer 11 is irradiated with active energy rays is preferably 60% or more as the lower limit value, more preferably 62% or more and more preferably 65% or more. If the lower limit of the gel fraction is above, the cohesive force of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer after curing becomes sufficient, and more excellent resistance to blistering can be exhibited. The gel fraction of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer after curing is preferably 95% or less, more preferably 90% or less, and most preferably 80% or less as the upper limit value. When the upper limit value of the gel fraction is above, the adhesive force of the pressure-sensitive adhesive layer after curing is secured, and sufficient durability can be obtained. The method of measuring the gel fraction of the pressure-sensitive adhesive (after irradiation with active energy rays) constituting the pressure-sensitive adhesive layer after curing is as shown in the following test examples.

(2-3) Change in gel fraction

The amount of change in gel fraction accompanying curing by activation energy ray irradiation of the active energy ray curable pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 11 (the gel fraction of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer after curing) Value obtained by subtracting the fraction) is preferably 5 points or more, particularly preferably 10 points or more, and more preferably 15 points or more. As the gel fraction increases, the resulting cured pressure-sensitive adhesive layer becomes more excellent in resistance to blistering. The upper limit of the increase in the gel fraction is not particularly limited. However, from the viewpoint of preventing the hardening of the pressure-sensitive adhesive layer after curing, the increase in the gel fraction is preferably 40 points or less, more preferably 30 points or less, It is particularly preferable that it is 25 points or less.

(3) Wet heat resistance

The moisture resistance and whitening whiteness of the pressure-sensitive adhesive according to the present embodiment can be quantitatively evaluated by the haze value as shown below.

That is, the pressure-sensitive adhesive layer 11 having a thickness of 50 탆 was sandwiched between a glass plate and a plastic plate having a thickness of 0.7 mm (a plastic plate laminated on a polycarbonate resin plate and a polymethyl methacrylate resin layer; a polycarbonate resin plate on the pressure- The pressure-sensitive adhesive layer 11 was cured by irradiating the active energy ray to form a pressure-sensitive adhesive layer after curing, and then subjected to a durability test in which the layered product was stored under the conditions of 85 ° C and 85% relative humidity for 1000 hours (Measured in accordance with JIS K7136: 2000, hereinafter the same) at the time of storage at room temperature and normal humidity of 23 ° C and 50% RH for 24 hours, minus the haze value before the durability test ) Is preferably less than 1.5, particularly preferably less than 1.2, more preferably less than 1.0.

Further, the pressure-sensitive adhesive layer 11 having a thickness of 250 占 퐉 was sandwiched between a glass plate and a plastic plate having a thickness of 0.7 mm (a plastic plate on which a polymethylmethacrylate resin layer was laminated on a polycarbonate resin plate; a polycarbonate resin plate on the pressure- The pressure-sensitive adhesive layer 11 was cured by irradiating the active energy ray to form a pressure-sensitive adhesive layer after curing, and then subjected to a durability test in which the layered product was stored under the conditions of 85 ° C and 85% relative humidity for 1000 hours (Point) obtained by subtracting the haze value before the durability test from the haze value when the sample is stored for 24 hours at room temperature and normal humidity at 23 ° C and 50% RH is preferably less than 1.0 and is preferably less than 0.7 , Particularly preferably less than 0.5, and more preferably less than 0.3.

Further, a pressure-sensitive adhesive layer 11 having a thickness of 50 탆 was sandwiched between a glass plate and a plastic plate having a thickness of 2.0 mm (a plastic plate in which a polymethylmethacrylate resin layer was laminated on a polycarbonate resin plate; a polycarbonate resin plate on the pressure- The pressure-sensitive adhesive layer 11 was cured by irradiating the active energy ray to form a pressure-sensitive adhesive layer after curing, and then subjected to a durability test in which the layered product was stored under the conditions of 85 ° C and 85% relative humidity for 1000 hours (Point) obtained by subtracting the haze value before the durability test from the haze value when the sample is stored in normal temperature and normal humidity at 23 占 폚 and 50% RH for 24 hours is preferably less than 8, particularly preferably less than 5 , And more preferably less than 1.5.

Further, a pressure-sensitive adhesive layer 11 having a thickness of 250 탆 was sandwiched between a glass plate and a plastic plate having a thickness of 2.0 mm (a plastic plate in which a polymethylmethacrylate resin layer was laminated on a polycarbonate resin plate; a polycarbonate resin plate on the pressure- The pressure-sensitive adhesive layer 11 was cured by irradiating the active energy ray to form a pressure-sensitive adhesive layer after curing, and then subjected to a durability test in which the layered product was stored under the conditions of 85 ° C and 85% relative humidity for 1000 hours (Point) obtained by subtracting the haze value before the durability test from the haze value when the sample is stored in normal temperature and normal humidity at 23 占 폚 and 50% RH for 24 hours is preferably less than 8, more preferably less than 6 , Particularly preferably less than 3, and more preferably less than 1.

When the difference in haze value is within the above range, the increase in the haze value is small even after being placed under the moist heat condition, and the whitening of the pressure-sensitive adhesive is suppressed. Further, a plastic plate, particularly a plastic plate having the above-described configuration, is relatively easy to permeate moisture under moist heat conditions. Therefore, in a laminate in which a glass plate and a plastic plate are sandwiched by a general cured pressure-sensitive adhesive layer, moisture permeates the plastic plate under moist heat conditions, and the moisture easily tends to reach the pressure-sensitive adhesive layer after curing. Therefore, in such a laminate, the pressure-sensitive adhesive layer after curing is likely to be whitened as compared with a laminate in which two pressure-sensitive adhesive layers are sandwiched between two glass plates. However, according to the pressure-sensitive adhesive sheet 1 of the present embodiment, even in the case of the laminate as described above, excellent heat and moisture resistance can be obtained. The test method for the anti-wet heat resistance described above is as shown in the following test examples.

(4) Haze value

In the pressure-sensitive adhesive sheet 1 according to the present embodiment, the pressure-sensitive adhesive layer 11 preferably has a haze value of 5% or less, more preferably 3% or less, particularly preferably 1% or less, desirable. If the haze value of the pressure-sensitive adhesive layer 11 is 5% or less, the transparency is extremely high and is suitable for optical use (for a display). The haze value of the pressure-sensitive adhesive layer 11 does not change even after curing by irradiation with active energy rays.

(5) Step follow-up rate

In the pressure-sensitive adhesive sheet 1 according to the present embodiment, the step following rate (%) expressed by the following formula in the pressure-sensitive adhesive layer after curing by curing the pressure-sensitive adhesive layer 11 by irradiation of an active energy ray is smaller than the lower limit value , More preferably not less than 5%, more preferably not less than 10%, particularly preferably not less than 15%, more preferably not less than 20%. The upper limit value of the step following rate is not particularly limited, but is usually preferably 80% or less, and particularly preferably 70% or less. The test method for the step difference followability is as shown in the following test example.

(%) = {(Height of stepped portion (m) maintained in a state of being filled without bubbling, lifting, peeling or the like after predetermined durability test) / (thickness of pressure-sensitive adhesive layer)} x 100

Since the follow-up rate of the step difference of the pressure-sensitive adhesive layer after curing is in the above-mentioned range, the pressure-sensitive adhesive layer after the curing satisfactorily follows the step of the display member constituting member even after the endurance test, and bubbles, Is suppressed, and generation of return loss of light is suppressed. As a result, it becomes possible to manufacture a display having a higher image quality.

(6) Adhesion

The adhesive force of the pressure-sensitive adhesive sheet 1 to the soda lime glass when the pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 according to the present embodiment is cured by irradiation of an active energy ray to form a pressure- , And the lower limit value is preferably 20 N / 25 mm or more, particularly preferably 25 N / 25 mm or more, more preferably 30 N / 25 mm or more. When the adhesive force of the adhesive sheet 1 is 20 N / 25 mm or more, the blister resistance is more excellent. On the other hand, the upper limit value of the adhesive force is not particularly limited, but is usually preferably 100 N / 25 mm or less, more preferably 90 N / 25 mm or less, and particularly preferably 80 N / 25 mm or less. The adhesive force is basically the adhesive force measured by the 180 degree peeling technique in accordance with JIS Z0237: 2009, and the specific test method is as shown in the following test example.

4. Use of adhesive sheet

A preferred use example of the pressure-sensitive adhesive sheet 1 according to the present embodiment will be described. One display body constituting member and another display body constituting member are joined by the adhesive layer 11 of the active energy ray-curable adhesive sheet 1. At least one of the one indicator body constituting member and the other indicator body constituting member is an ultraviolet shielding member. Then, the adhesive layer 11 is irradiated with an active energy ray via the display member constituting the ultraviolet shielding member to cure the pressure-sensitive adhesive layer 11 to form a pressure-sensitive adhesive layer (cured pressure-sensitive adhesive layer 11 '), .

The ultraviolet shielding member has a light transmittance at a wavelength of 360 nm of 20% or less, a light transmittance at a wavelength of 390 nm of 10% or more, and a light transmittance of a wavelength of 390 nm at a wavelength of 360 nm.

[Display]

The adhesive sheet 1 according to the present embodiment can be used for manufacturing the display body 2 as illustrated in Fig. As shown in Fig. 2, the display body 2 according to the present embodiment includes a first display body constituting member 21 (one display body constituting member) having at least a step on the side to be conjugated, A pressure-sensitive adhesive layer 11 (a second pressure-sensitive adhesive layer) is disposed between the display body constituting member 22 (another display body constituting member) and the first display body constituting member 21 and the second display body constituting member 22, '). In the display body 2 according to this embodiment, the first display body constituting member 21 has a step on the surface of the pressure-sensitive adhesive layer 11 'side or the side of the pressure-sensitive adhesive layer 11 side after curing, Has a stepped portion by the printed layer 3, but the present invention is not limited to this.

Here, when one of the display body constituting members (for example, the first display body constituting member 21) is an ultraviolet screening member, the other display body constructing member (for example, ) Is a member which is deteriorated in performance by ultraviolet irradiation or a member in which the active energy ray can not be irradiated to the pressure-sensitive adhesive layer 11 from the other side of the display body constituting member desirable. When the pressure sensitive adhesive sheet 1 according to the above-described embodiment is used, even when the member having such a restriction is used for the display member constituting member, the pressure sensitive adhesive layer 11 is irradiated with the active energy ray from the side of the ultraviolet shielding member, Cured to form a pressure-sensitive adhesive layer 11 ', and a display body 2 having excellent blister resistance even under severe high-temperature and high-humidity conditions can be obtained.

The cured pressure-sensitive adhesive layer 11 'of the display body 2 is obtained by curing the pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 described above by irradiation with active energy rays. The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 11 'after the curing has a crosslinked structure composed of the (meth) acrylic acid ester polymer (A) and the crosslinking agent (B) (Polymer), and may further contain a photopolymerization initiator (D) and an additive, if desired. In this case, it is presumed that the polymerized active energy ray-curable component (C) is entangled with a crosslinked structure composed of the (meth) acrylic acid ester polymer (A) and the crosslinking agent (B) to form a higher-order structure.

The photopolymerization initiator (D) contained in the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer (11 ') after curing is preferably such that the photopolymerization initiator (D) contained in the pressure-sensitive adhesive composition (P) will be. Therefore, the content thereof is not large, and is usually 0.00001 mass% or more and 0.1 mass% or less, preferably 0.0001 mass% or more and 0.01 mass% or less in the pressure-sensitive adhesive.

In the display body 2 according to the present embodiment, at least one of the first display body constituting member 21 and the second display body constituting member 22 is formed of a plastic plate. Here, the plastic plate is usually susceptible to permeation of water vapor under conditions of high temperature and high humidity, for example, under the conditions of 85 DEG C and 85% RH. Therefore, blisters such as bubbles, peeling, peeling, and the like may be generated at the interface between the plastic plate and the cured pressure-sensitive adhesive layer 11 'due to the water vapor, or the cured pressure-sensitive adhesive layer 11' . However, even if the display body 2 according to the present embodiment is provided with such a plastic plate, since the cured pressure-sensitive adhesive layer 11 'is derived from the pressure-sensitive adhesive sheet 1 according to the present embodiment , The generation of blisters and the whitening of the pressure-sensitive adhesive layer 11 'after curing can be satisfactorily suppressed.

The plastic plate is not particularly limited and includes, for example, an acrylic resin plate such as a polycarbonate resin (PC) plate or a polymethyl methacrylate (PMMA) plate, a polymethylmethacrylate resin layer A plastic plate laminated with an acrylic resin layer. The above-mentioned polycarbonate resin plate may contain a resin other than a polycarbonate resin as a constituent material thereof, and the above-mentioned acrylic resin plate may contain a resin other than an acrylic resin do.

The thickness of the plastic plate is not particularly limited, but is usually 0.2 to 5 mm, preferably 0.4 to 3 mm, particularly preferably 0.6 to 2.5 mm, and more preferably 1 to 2.1 mm.

The plastic plate may contain an ultraviolet absorber. Since the pressure-sensitive adhesive layer 11 contains a photopolymerization initiator (D) having an absorbance at a wavelength of 390 nm of 0.3 or more, even when an active energy ray is irradiated to the pressure-sensitive adhesive layer 11 via a plastic plate containing an ultraviolet absorber, (11) is sufficiently cured to obtain a cured pressure-sensitive adhesive layer (11 ') having high cohesive strength. Thus, even when the display body 2 is placed under a high-temperature and high-humidity condition for a long time, the occurrence of blisters at the interface between the plastic plate and the cured pressure-sensitive adhesive layer 11 'is suppressed.

In the display body 2 according to the present embodiment, at least one of the first display body constituting member 21 and the second display body constituting member 22 has a thickness of 100 m and a thickness of 40 (M 2 · 24 h · 100 μm) or more and preferably 0.01 g / (m 2 · 24 h · 100 μm) or more as measured according to JIS K7129 under the conditions of , And more preferably 0.05 g / (m 2 · 24 h · 100 μm) or more. The water vapor permeability is preferably 100 g / (m 2 · 24 h · 100 μm) or less, particularly preferably 95 g / (m 2 · 24 h · 100 μm) or less and 85 g / (m 2 · 24 h · 100 μm) More preferable. Since the pressure-sensitive adhesive layer 11 'after curing is derived from the pressure-sensitive adhesive sheet 1 according to the present embodiment, even if the plastic plate is made of a material having the above-mentioned water vapor permeability and moisture is easily permeable, And the whitening of the pressure-sensitive adhesive layer 11 'after curing can be satisfactorily suppressed.

The water vapor permeability of the material constituting the above-mentioned plastic plate is measured in accordance with JIS K7129 under the conditions of 40 DEG C and 90% RH with respect to the water vapor permeability (measured value ), And then calculating from the measurement result the thickness of the plastic plate to 100 mu m using the following calculation formula.

Water vapor permeability (measured value) x (Actual thickness of plastic plate / 100) Water vapor permeability (g / (m 2 24h 100 m)

The first display body constituting member 21 is preferably a protective panel made of the plastic plate described above, and the plastic plate preferably contains an ultraviolet absorbent. In this case, the display body 2 is excellent in light resistance, and even if ultraviolet rays are projected from the side of the first display body constituting member 21 to the display body 2 after the production, the pressure-sensitive adhesive layer 11 ' The deterioration of the second display body constituting member 22 in the lower layer is suppressed. In particular, in the pressure-sensitive adhesive layer 11 'after curing, excellent blister resistance can be maintained satisfactorily.

Various functional layers (a transparent conductive film, a metal layer, a silica layer, a hard coat layer, an antiglare layer, or the like) may be provided on one side or both sides of the plastic plate constituting the first display body constituting member 21, . The transparent conductive film and the metal layer may be patterned.

The second display body constituting member 22 may be a glass plate or an optical member to be affixed to the first display body constituting member 21, a display module (for example, a liquid crystal (LCD) module, a light emitting diode (LED) Module, an organic electroluminescence (organic EL) module or the like), an optical member as a part of the display body module, or a laminate including the display body module. The optical member, the display module, the laminate, and the like may be provided with a glass plate.

The glass plate is not particularly limited and includes, for example, chemically strengthened glass, non-alkali glass, quartz glass, soda lime glass, barium-strontium glass, aluminosilicate glass, lead glass, borosilicate glass, barium borosilicate glass, . The thickness of the glass plate is not particularly limited, but is usually 0.1 to 10 mm, preferably 0.2 to 5 mm, and more preferably 0.8 to 2 mm.

Various functional layers (a transparent conductive film, a metal layer, a silica layer, a hard coat layer, an antiglare layer, or the like) may be provided on one side or both sides of the glass plate constituting the second display body constituting member 22, . The transparent conductive film and the metal layer may be patterned.

Examples of the optical member include a light-scattering film, a polarizing plate (polarizing film), a polarizer, a retardation film (phase difference film), a viewing angle compensation film, a brightness enhancement film, a contrast enhancement film, a liquid crystal polymer film, A film, and a transparent conductive film. Examples of the shake-prevention film include a hard coat film formed by forming a hard coat layer on one side of a base film. The optical member may contain an ultraviolet absorber.

The second display body constituting member 22 is preferably made of a material whose performance deteriorates by ultraviolet irradiation or an active energy ray-curable pressure-sensitive adhesive layer 11 from the second display body constituting member 22 side It is preferable that the member is structured such that the energy ray can not be irradiated. Specifically, the second display body constituting member 22 is preferably a laminate including a display body module or a display body module.

When the first display body constituting member 21 is a protective panel, the printed layer 3 is formed on the side of the cured pressure-sensitive adhesive layer 11 'of the first display body constituting member 21 on the framed frame .

The material constituting the print layer 3 is not particularly limited, and known materials for printing are used. The thickness of the print layer 3, that is, the height of the step, is usually about 3 to 50 mu m. The pressure-sensitive adhesive layer 11 'after the curing exhibits sufficient followability with respect to the printing layer 3 as described above, and bubbles and the like do not occur at the interface with the printing layer 3.

As the display body 2, for example, a liquid crystal (LCD) display, a light emitting diode (LED) display, an organic electroluminescence (organic EL) display, an electronic paper and the like may be mentioned. The display body 2 may be a member constituting a part of them.

In order to manufacture the display body 2, for example, one of the release sheets 12a of the pressure-sensitive adhesive sheet 1 is peeled off, and the pressure-sensitive adhesive layer 11, on which the pressure-sensitive adhesive sheet 1 is exposed, To the side of the constituent member 21 on which the print layer 3 is present. At this time, since the pressure sensitive adhesive layer 11 is excellent in the followability of the initial step difference, it is possible to suppress the occurrence of a gap or lifting in the vicinity of the stepped portion by the print layer 3.

The other release sheet 12b is peeled from the pressure-sensitive adhesive layer 11 of the pressure-sensitive adhesive sheet 1 and the pressure-sensitive adhesive layer 11 and the second display member constituting member 22, Are laminated to obtain a laminate. As another example, the order of combining the first display body constituent member 21 and the second display body constituent member 22 may be changed.

After obtaining the laminate, an active energy ray is irradiated to the pressure-sensitive adhesive layer 11 in the laminate. The irradiation of the active energy ray to the pressure-sensitive adhesive layer 11 is usually carried out over either the first display body constituting member 21 or the second display body constituting member 22, Is performed over the display body constituting member (21). At this time, the active energy ray may be irradiated over the display body constituting member (first display body constituting member 21) composed of the plastic plate containing the ultraviolet absorber. As described above, since the active energy ray of the wavelength for curing the pressure-sensitive adhesive layer 11 is hardly absorbed by the ultraviolet absorbent, the pressure-sensitive adhesive layer 11 is sufficiently cured by the irradiation of the active energy rays, Layer 11 '. Thereby, the display body 2 having excellent blister resistance can be obtained.

The active energy ray used in this embodiment has a substantial intensity of light emission in a wavelength range exceeding 365 nm as described above. As the irradiation light source of such an active energy ray, for example, a high pressure mercury lamp, a metal halide lamp, a xenon lamp and the like are preferably used. The irradiation amount of the active energy ray is preferably about 50 to 1000 mW / cm 2. The amount of light is preferably 50 to 10000 mJ / cm 2, more preferably 80 to 5000 mJ / cm 2, and particularly preferably 200 to 2000 mJ / cm 2.

In the display body 2 according to the present embodiment, the water vapor permeability of the first display body constituting member 21 is not less than 0.001 g / (m 2 · 24 h) and not more than 100 g / (m 2 · 24 h) It is preferable that the moisture permeability of the member 22 is 0.001 g / (m < 2 > 24h) or less. Here, when a plastic plate is used as the first display body constituting member 21 and a glass plate is used as the second display body constituting member 22, the first display body constituting member 21 and the second display body constituting member 22, And the water vapor permeability of the water vapor permeable film 22 is likely to fall within the above-mentioned range. If the display body 2 including the first display body constituting member 21 and the second display body constituting member 22 is left under high temperature and high humidity conditions, ), And is likely to reach the pressure-sensitive adhesive layer 11 'after curing. However, since the post-curing pressure-sensitive adhesive layer 11 'is derived from the pressure-sensitive adhesive sheet 1 according to the present embodiment, the occurrence of blisters and whitening of the pressure-sensitive adhesive layer 11' after curing can be satisfactorily suppressed . The above-described water vapor permeability of the first display body constituting member 21 is particularly preferably at least 0.05 g / (m 2 24 h), more preferably at least 0.1 g / (m 2 24 h). The water vapor permeability is particularly preferably 80 g / (m 2 · 24 h) or less, more preferably 50 g / (m 2 · 24 h) or less. The above-described water vapor transmission rate in the second display body constituting member 22 is particularly preferably at least 0.0001 g / (m 2 24 h), more preferably at least 0.0005 g / (m 2 24 h).

The water vapor permeability of each of the first display body constituting member 21 and the second display body constituting member 22 described above was measured in accordance with JIS K7129 under conditions of 40 DEG C and 90% RH using a transmittance meter . In this measurement, the thicknesses of the first display body constituting member 21 and the second display body constituting member 22 are the same as those actually used in the display body 2. Therefore, the above-described steam permeability is not the water vapor permeability as the material of each of the first display body constituting member 21 and the second display body constituting member 22, but the water vapor permeability as a member constituting the display body 2 .

In the display body 2 according to the present embodiment, since the cured pressure-sensitive adhesive layer 11 'is obtained from the pressure-sensitive adhesive layer 11 (pressure-sensitive adhesive composition P) described above, (For example, 85 ° C, 85% RH, 1000 hours), the generation of blisters at the interface between the display body constituting members 21, 22 and the cured pressure-sensitive adhesive layer 11 ' do. Further, even if the display body 2 is returned to normal temperature and normal humidity after being placed under a strict high temperature and high humidity condition (for example, 85 ° C, 85% RH, 1000 hours), the cured pressure-sensitive adhesive layer 11 ' .

The present invention also provides a constituent constituting a part of the above-described display body (display body 2). This constitution comprises one display body constituting member, another display body constituting member, and a post-curing pressure-sensitive adhesive layer for bonding one display body constituting member and the other display body constituting member to each other. The one display body constructing member is an ultraviolet shielding member having ultraviolet shielding ability. The other display body constituting member may be an ultraviolet transmitting member having ultraviolet transmitting property.

The cured pressure-sensitive adhesive layer is obtained by curing a pressure-sensitive adhesive layer having an active energy ray-curable property. The active energy radiation curable pressure sensitive adhesive layer is preferably the pressure sensitive adhesive layer 11 of the pressure sensitive adhesive sheet 1 according to the above embodiment and is applied to the pressure sensitive adhesive layer 11 through the display member constituting the ultraviolet blocking member It is preferable that the pressure sensitive adhesive layer 11 is irradiated with an active energy ray to form a cured pressure-sensitive adhesive layer in a fully cured state.

Preferable examples of the one display body constituting member include a protective panel having a plastic plate containing an ultraviolet absorber, for example. Examples of the other display member constituting member include a glass plate and various optical members as described above.

The embodiments described above are described for the purpose of facilitating understanding of the present invention and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design modifications and equivalents falling within the technical scope of the present invention.

For example, either of the release sheets 12a and 12b in the pressure-sensitive adhesive sheet 1 may be omitted. The first display body constituting member 21 may have a step difference other than the print layer 3, or may not have a step difference. In addition to the first display body constituting member 21, the second display body constituting member 22 may have a step on the side of the cured pressure-sensitive adhesive layer 11 '.

(Example)

Hereinafter, the present invention will be described in more detail with reference to examples, 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 polymer (A)

55 parts by mass of 2-ethylhexyl acrylate, 5 parts by mass of N-acryloylmorpholine, 15 parts by mass of isobornyl acrylate and 25 parts by mass of 2-hydroxyethyl acrylate were copolymerized by solution polymerization to obtain (meth) acrylic acid To prepare an ester polymer (A). The molecular weight of the (meth) acrylic acid ester polymer (A) was measured by the method described later, and the weight average molecular weight (Mw) was 60,000. The glass transition temperature (Tg; 占 폚) of the (meth) acrylic acid ester polymer (A) is determined based on the glass transition temperature (Tg) of the respective monomers constituting the (meth) acrylic acid ester polymer , And calculated by the formula of FOX, it was -36.5 占 폚.

2. Preparation of adhesive composition

100 parts by mass of the (meth) acrylic acid ester polymer (A) obtained in the above Step 1 (solid content conversion value: the same in the following) and 0.18 parts by mass of trimethylolpropane-modified tolylene diisocyanate (Toyo Khemsha, product name: BHS8515) And 7 parts by mass of? -Caprolactone-modified tris- (2-acryloxyethyl) isocyanurate (Shin-Nakamura Kagakusha Co., Ltd., product name "A-9300-1CL") as an active energy ray- And 0.7 parts by mass of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (D1) as a photopolymerization initiator (D) and 3 parts by mass of 3-glycidoxypropyltrimethoxysilane KBM-403 ") were mixed and sufficiently stirred, and the mixture was diluted with methyl ethyl ketone to obtain a coating solution of the adhesive composition.

Table 1 shows the respective blend (solid content conversion value) of the adhesive composition when the (meth) acrylic acid ester polymer (A) was changed to 100 parts by mass (solid content conversion value). Details of the abbreviations, etc. shown in Table 1 are as follows.

[(Meth) acrylic acid ester polymer (A)]

 2EHA: 2-ethylhexyl acrylate

 BA: n-butyl acrylate

 ACMO: N-acryloylmorpholine

 IBXA: isobornyl acrylate

 HEA: 2-hydroxyethyl acrylate

 HEMA: 2-hydroxyethyl methacrylate

[Photopolymerization initiator (D)]

 D1: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide

 D2: Bis (2,4-cyclopentadienyl) bis [2,6-difluoro-3- (1-pyryl) phenyl]

 D3: A mixture of benzophenone and 1-hydroxycyclohexyl phenyl ketone in a mass ratio of 1: 1

3. Production of adhesive sheet

The coating solution of the sticky composition obtained in the above Step 2 was coated on a release treatment surface of a heavy-duty release sheet (LINTEC Corporation, product name " SP-PET752150 ") in which one side of the polyethylene terephthalate film was stripped with a silicone- Thereafter, the coating layer was heat-treated at 90 占 폚 for 1 minute to form a coating layer (thickness: 50 占 퐉). The peeling treatment side of the obtained intermediate peelable peel sheet with the coating layer and the peel treated side of the lightly peelable peel sheet (LINTEC CORPORATION, product name " SP-PET381130 ") in which one side of the polyethylene terephthalate film was peeled off with a silicone- And cured for 7 days under conditions of 23 캜 and 50% RH to prepare a pressure-sensitive adhesive sheet having a structure of a heavy-duty release sheet / active energy ray-curable pressure-sensitive adhesive layer (thickness: 50 탆) / light- did.

The thickness of the pressure-sensitive adhesive layer is a value measured using a constant pressure thickness gauge (trade name: " PG-02 ") according to JIS K7130.

[Examples 2 to 4]

The types and ratios of the respective monomers constituting the (meth) acrylic acid ester polymer (A), the weight average molecular weight (Mw) of the (meth) acrylic acid ester polymer (A) A pressure-sensitive adhesive sheet was produced in the same manner as in Example 1, except that the pressure-sensitive adhesive sheet was changed as described above.

[Example 5]

1. Preparation of (meth) acrylic acid ester polymer (A)

50 parts by mass of 2-ethylhexyl acrylate, 5 parts by mass of N-acryloylmorpholine, 15 parts by mass of isobornyl acrylate and 30 parts by mass of 2-hydroxyethyl acrylate were copolymerized by solution polymerization to obtain (meth) acrylic acid To prepare an ester polymer (A). The molecular weight of the (meth) acrylic acid ester polymer (A) was measured by the method described later, and the weight average molecular weight (Mw) was 60,000. The glass transition temperature (Tg; 占 폚) of the (meth) acrylic acid ester polymer (A) is determined based on the glass transition temperature (Tg) of the respective monomers constituting the (meth) acrylic acid ester polymer And FOX, it was -33.6 ° C.

2. Preparation of adhesive composition

100 parts by mass of the (meth) acrylic acid ester polymer (A) obtained in the above Step 1 and 0.20 parts by mass of trimethylolpropane-modified tolylene diisocyanate (Toyo Chemicals Co., Ltd., product name "BHS8515") as a crosslinking agent (B) 7 parts by mass of? -Caprolactone-modified tris- (2-acryloxyethyl) isocyanurate (Shin-Nakamura Kagakusha Co., Ltd., product name "A-9300-1CL") as component (C) 0.7 parts by mass of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (D1) and 3 parts by mass of 3-glycidoxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., product name: KBM-403 ) Were mixed, sufficiently stirred, and diluted with methyl ethyl ketone to obtain a coating solution of the adhesive composition.

3. Production of adhesive sheet

The coating solution of the sticky composition obtained in the above Step 2 was coated on a release treatment surface of a heavy-duty release sheet (LINTEC Corporation, product name " SP-PET752150 ") in which one side of the polyethylene terephthalate film was stripped with a silicone- Thereafter, the coated layer (thickness: 50 mu m) was formed by heat treatment at 90 DEG C for 1 minute to prepare a heavy peelable peeling sheet with a coating layer.

On the other hand, the coating solution of the sticky composition obtained in the above Step 2 was applied to a release treatment surface of a lightly peelable release sheet (LINTEC Corporation, product name "SP-PET381130") in which one surface of a polyethylene terephthalate film was peeled off with a silicone- (Thickness: 50 占 퐉) was formed by heat treatment at 90 占 폚 for 1 minute to prepare a lightly recyclable release sheet having a coating layer.

The surface on the coating layer side of the heavy peelable peeling sheet with the coating layer obtained as described above and the surface on the coating layer side in one of the lightly peelable peeling sheets with the coating layer obtained as described above were pasted, A coating layer having a total thickness of 100 占 퐉 was sandwiched between a heavy-weight releasing peel sheet and a light-weight releasing peel sheet to obtain a first stack body.

Subsequently, the exposed surface of the coated layer exposed by peeling off the lightly recoil peeling sheet from the first laminate was pasted on the side of the coated layer in one of the lightly peelable peeling sheets with coating layers obtained above, And a coating layer having a total thickness of 150 mu m was sandwiched between the heavy-weight releasing sheet and the light-weight releasing sheet to obtain a second stack.

Subsequently, the exposed surface of the coated layer exposed by peeling off the lightly recoil peeling sheet from the second laminate was pasted on the side of the coated layer in one of the lightly peelable release sheets having the coated layer obtained above, A coating layer having a total thickness of 200 占 퐉 was sandwiched between a heavy-weight releasing peel sheet and a light-weight releasing peel sheet to obtain a third stack body.

The exposed surface of the coated layer exposed by peeling off the lightly recoated peeling sheet from the third laminate was peeled off from the surface of the coated layer side of one of the light- To obtain a fourth laminate in which a coating layer having a total thickness of 250 占 퐉 was sandwiched between a heavy-weight releasing peel sheet and a lightweight releasing peel sheet.

The fourth laminate was cured for 7 days under the conditions of 23 ° C and 50% RH to obtain a pressure-sensitive adhesive layer (thickness: 250 μm) having a structure of a heavy-weight releasing sheet / active energy ray- Sheet.

[Example 6]

A pressure-sensitive adhesive sheet was produced in the same manner as in Example 5, except that the kinds of the photopolymerization initiator (D) were changed as shown in Table 1.

[Examples 7 to 8 and Comparative Examples 1 to 6]

(A), the kind and ratio of each monomer constituting the (meth) acrylic acid ester polymer (A), the weight average molecular weight (Mw) of the (meth) acrylic acid ester polymer (A), the blending amount of the crosslinking agent ), And the kind and blending amount of the photopolymerization initiator (D) were changed as shown in Table 1, a pressure-sensitive adhesive sheet was produced.

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

<Measurement Conditions>

GPC measurement apparatus: Tosoh Co., Ltd., HLC-8020

· GPC column (pass in the following order): Dososaje

  TSK guard column HXL-H

  TSK gel GMHXL (× 2)

  TSK gel G2000HXL

Measurement solvent: tetrahydrofuran

· Measuring temperature: 40 ℃

[Test Example 1] (Measurement of water vapor transmission rate)

The coating solution of the sticky composition prepared in Examples and Comparative Examples was applied to a release treatment surface of a heavy-duty release sheet (LINTEC SHAZE, product name &quot; SP-PET752150 &quot;) in which one side of a polyethylene terephthalate film was stripped with a silicone- , And then subjected to a heat treatment at 90 占 폚 for 1 minute to form a coating layer (thickness: 50 占 퐉) to prepare a heavy peelable peeling sheet with a coating layer.

On the other hand, the coating solution of the sticky composition prepared in Examples and Comparative Examples was applied to the release treatment surface of a lightly peelable release sheet (LINTEC SHAZETE, product name &quot; SP-PET381130 &quot;) in which one side of a polyethylene terephthalate film was peeled off with a silicone- Coated with a knife coater and then heat-treated at 90 占 폚 for 1 minute to form a coating layer (thickness: 50 占 퐉) to prepare a lightly reclosable peeling sheet with a coating layer.

The surface on the side of the coating layer of the heavy peelable release sheet with the coating layer obtained as described above and the side of the coating layer side of the lightly peelable release sheet with the coating layer obtained as described above were bonded to each other to give a total thickness of 100 Mu m was sandwiched between the heavy-weight releasing sheet and the light-weight releasing sheet, thereby obtaining a laminate. This laminate was cured for 7 days under the conditions of 23 캜 and 50% RH to form a pressure-sensitive adhesive layer in which a heavy-breakable release sheet, an active energy radiation curable pressure-sensitive adhesive layer having a thickness of 100 탆, To prepare a pressure-sensitive adhesive sheet.

The lightly peelable release sheet was peeled off from the resulting pressure-sensitive adhesive sheet, and a plastic plate F (containing an ultraviolet absorber) having a thickness of 2.0 mm in which a polymethyl methacrylate resin (PMMA) layer was laminated on a polycarbonate resin (PC) Of the polycarbonate resin (PC) plate side. Next, the active energy ray curable pressure-sensitive adhesive layer was irradiated with an active energy ray over the plastic plate F under the following conditions to form a pressure-sensitive adhesive layer after curing.

&Lt; Active energy ray irradiation conditions >

· Using high pressure mercury lamp

Illumination 200 mW / cm 2, light quantity 1000 mJ / cm 2

· Illumination and light meter use UVPF-A1 for eye graphics

Subsequently, the cured pressure-sensitive adhesive layer was sandwiched between two pieces of Tetralon mesh # 380, and a transmittance measuring machine (product name: "L80-5000" manufactured by LYSSY Co., Ltd.) was placed under the conditions of 40 ° C. and 90% RH in accordance with JIS K7129 (G / (m &lt; 2 &gt; 24h, 100 mu m)) was measured. The results are shown in Table 2.

[Test Example 2] (Measurement of absorbance)

An acetonitrile solution having a concentration of 0.1% by mass of the photopolymerization initiator used in the examples and comparative examples was prepared, and the absorbance in the range of 200-500 nm in the solution was measured by UV-Vis-NIR ) Was measured using a spectrophotometer (product name: "UV-3600" manufactured by Shimadzu Corporation). Based on the results, the maximum absorption wavelength (nm) at an absorbance at a wavelength of 390 nm and an absorbance at a wavelength of 200 to 500 nm was derived. The results are shown in Table 1.

[Test Example 3] (Measurement of gel fraction)

The pressure-sensitive adhesive sheet obtained in Examples and Comparative Examples was cut into a size of 80 mm x 80 mm, the pressure-sensitive adhesive layer of active energy radiation curable property was wrapped with a polyester mesh (mesh size 200), the mass was weighed with a precision balance , And the mass of the adhesive alone was calculated by subtracting the mass of the mesh alone. The mass at this time is defined as M1.

Next, the adhesive wrapped with the polyester-made mesh was immersed in ethyl acetate at room temperature (23 ° C) for 24 hours. Thereafter, the pressure-sensitive adhesive was taken out and air-dried for 24 hours under an environment of a temperature of 23 ° C and a relative humidity of 50%, and further dried in an oven at 80 ° C for 12 hours. After drying, the mass was weighed with a precision balance, and the mass of the adhesive alone was calculated by subtracting the mass of the mesh alone. Let the mass at this time be M2. The gel fraction (%) is represented by (M2 / M1) x100. As a result, the gel fraction (before active energy ray irradiation) of the pressure-sensitive adhesive (active energy ray-curable pressure-sensitive adhesive) was derived. The results are shown in Table 2.

The lightly peelable release sheet was peeled off from the resulting pressure-sensitive adhesive sheet, and a plastic plate F (containing an ultraviolet absorber) having a thickness of 2.0 mm in which a polymethyl methacrylate resin (PMMA) layer was laminated on a polycarbonate resin (PC) Of the polycarbonate resin (PC) plate side. Next, the active energy ray-curable pressure-sensitive adhesive layer was irradiated with an active energy ray over the plastic plate F under the same conditions as in Test Example 1 to irradiate the active energy rays to form a pressure-sensitive adhesive layer after curing. A gel fraction (after irradiation with active energy rays) was derived for the pressure-sensitive adhesive of the pressure-sensitive adhesive layer after the curing in the same manner as described above. Further, a value obtained by subtracting the gel fraction before irradiation with the active energy ray from the gel fraction after irradiation with the active energy ray was calculated (change amount; point). The results are shown in Table 2.

[Test Example 4] (Measurement of adhesive force)

The lightly peelable release sheet was peeled off from the pressure-sensitive adhesive sheet obtained in Examples and Comparative Examples and the exposed pressure-sensitive adhesive layer was laminated on a polyethylene terephthalate (PET) film (Toyobo Co., Ltd., product name: "PET A4300" , Thickness: 100 占 퐉) to obtain a layered product of a pressure-sensitive adhesive layer of heavy-weight peeling sheet / active energy ray-curable adhesive / PET film. The obtained laminate was cut into a width of 25 mm and a length of 100 mm.

Releasing sheet was peeled off from the laminate under an environment of 23 占 폚 and 50% RH, and the exposed pressure-sensitive adhesive layer was attached to soda lime glass (Nihon Itagarasu Co.) MPa, at 50 DEG C for 20 minutes. Thereafter, a plastic plate F (containing an ultraviolet absorber) having a thickness of 2.0 mm and laminated with a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin (PC) plate was placed on the PET film. Over the plastic plate F and the PET film, the pressure-sensitive adhesive layer was irradiated with active energy rays under the same conditions as those in Test Example 1 to irradiate the active energy rays to form a pressure-sensitive adhesive layer after curing by curing the pressure-sensitive adhesive layer. The sample having the pressure-sensitive adhesive layer after curing was allowed to stand for 24 hours under the conditions of 23 占 폚 and 50% RH. Then, using a tensile tester (Orientec Corporation, Tensilon) The adhesive force (N / 25 mm) was measured under the conditions shown in Fig. Conditions other than those described herein were measured in accordance with JIS Z 0237: 2009. The results are shown in Table 2.

[Test Example 5] (Measurement of haze value)

The lightly peelable release sheet was peeled off from the resulting pressure-sensitive adhesive sheet, and a plastic plate F (containing an ultraviolet absorber) having a thickness of 2.0 mm in which a polymethyl methacrylate resin (PMMA) layer was laminated on a polycarbonate resin (PC) Of the polycarbonate resin (PC) plate side. Next, the above active energy rays-curable pressure-sensitive adhesive layer was irradiated with an active energy ray over the above-mentioned plastic plate F under the same conditions as in Test Example 1 to irradiate the active energy rays, thereby forming a pressure-sensitive adhesive layer after curing. The haze value (%) of the pressure-sensitive adhesive layer after the curing was measured using a haze meter (product name "NDH-2000" manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with JIS K7136: 2000. The results are shown in Table 2.

[Test Example 6] (Measurement of step following rate)

(UV-curable ink, product name: POS-911 Muka) was applied on the surface of a glass plate (product name: Corning Glass Eagle XG, length 90 mm x width 50 mm x thickness 0.5 mm) (Outline: 90 mm in length x 50 mm in width and 5 mm in width) so as to be one of 10 占 퐉, 15 占 퐉, 20 占 퐉 and 30 占 퐉. Next, the printed ultraviolet curable ink was cured by irradiating ultraviolet rays (80 W / cm 2, metal halide lamp 2, lamp height 15 cm, belt speed 10 to 15 m / min) : Any one of 10 占 퐉, 15 占 퐉, 20 占 퐉, 30 占 퐉, 50 占 퐉, 100 占 퐉 and 150 占 퐉).

The lightly curled release sheet was peeled off from the pressure-sensitive adhesive sheet obtained in Examples and Comparative Examples, and the exposed active energy ray-curable pressure-sensitive adhesive layer was laminated on a polyethylene terephthalate (PET) film (Toyobo Co., Thickness: 100 mu m). Next, the intermediate release type peeling sheet was peeled to expose the pressure-sensitive adhesive layer, and a laminate (product name: &quot; LPD3214 &quot;) was laminated on each stepped glass plate so that the pressure- did. Thereafter, the autoclave treatment was carried out for 30 minutes under the conditions of 50 DEG C and 0.5 MPa, and left at normal pressure, 23 DEG C and 50% RH for 24 hours.

Next, a 2.0 mm-thick plastic plate F (containing an ultraviolet absorber) in which a polymethyl methacrylate resin (PMMA) layer was laminated on a polycarbonate resin (PC) plate was placed on the PET film. Then, the active energy ray-curable pressure-sensitive adhesive layer over the plastic plate F and the PET film was irradiated with active energy rays under the same conditions as those in Test Example 1 to cure the pressure-sensitive adhesive layer to form a pressure-sensitive adhesive layer did. Subsequently, the laminate was stored for 72 hours under a high-temperature and high-humidity condition of 85 DEG C and 85% RH (endurance test), and then the step traceability was evaluated. The step following property is determined by whether or not the printed step is completely filled by the pressure-sensitive adhesive layer after curing. When bubbles, lifting, peeling, or the like are observed at the interface between the printed step and the cured pressure-sensitive adhesive layer, It can not be done. Here, the step following ability was evaluated as a step following rate (%) expressed by the following equation. The results are shown in Table 2.

(%) = {(Height of stepped portion (m) maintained in a state of being filled without bubbling, lifting, peeling, etc. after durability test) / (thickness of pressure-sensitive adhesive layer after curing)} x 100

[Test Example 7] (Evaluation of blister resistance)

The active energy ray-curable pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained in Examples and Comparative Examples was laminated on a soda lime glass (Nippon Electric Glass Co., Ltd., thickness 1.1 mm) and a plastic plate (no UV cut / Respectively. Thereafter, the autoclave treatment was carried out for 20 minutes under the conditions of 50 DEG C and 0.5 MPa, and left at normal pressure, 23 DEG C and 50% RH for 24 hours. The plastic plates shown in Table 2 are as follows.

[No UV cut]

Plastic plate A: Acrylic resin plate (thickness: 0.7 mm, not containing ultraviolet absorber)

Plastic plate B: A plastic plate (thickness: 1.5 mm, without ultraviolet absorber) laminated with a polymethyl methacrylate (PMMA) layer on a polycarbonate resin (PC) plate and a polycarbonate resin Contact with

Plastic plate C: Polycarbonate resin plate (thickness: 2 mm, not containing ultraviolet absorber)

[With UV cut]

Plastic plate D: A plastic plate (thickness: 0.7 mm, containing ultraviolet absorber) and a polycarbonate resin (PC) plate laminated with a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin contact

Plastic plate E: A plastic plate (thickness: 1 mm, containing ultraviolet absorber) and a polycarbonate resin (PC) plate laminated with a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin contact

Plastic plate F: A plastic plate (thickness: 2 mm, containing ultraviolet absorber) and a polycarbonate resin (PC) plate laminated with a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin contact

Next, the above active energy ray-curable pressure-sensitive adhesive layer was irradiated with an active energy ray over the above-mentioned plastic plate under the same condition as in Test Example 1 to irradiate the active energy ray, and the pressure-sensitive adhesive layer was cured to obtain a pressure-sensitive adhesive layer after curing. Subsequently, the laminate was stored for 1000 hours under high temperature and high humidity conditions of 85 캜 and 85% RH. Thereafter, the state at the interface between the pressure-sensitive adhesive layer and the adherend after curing was confirmed by naked eyes and the blister resistance was evaluated by the following criteria. The results are shown in Table 2.

 ◎: No bubbles, peeling, peeling

 ○: Two or one bubbles having a diameter of less than 1 mm were generated, but there was no lifting or peeling.

 △: Bubbles having a diameter of less than 1 mm were generated from three or more but less than nine, but there was no peeling or peeling off

 X: Bubbles, peeling, peeling occurred

[Test 8] (Evaluation of anti-wet heat whitening property)

The active energy ray-curable pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained in the examples and comparative examples was formed by laminating a 1.1-mm-thick non-alkali glass plate and a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin And sandwiched between polycarbonate resin (PC) plate sides of a plastic plate D (containing an ultraviolet absorber) of 0.7 mm to obtain a laminate (constitution A). The obtained laminate was subjected to autoclave treatment at 50 캜 under 0.5 MPa for 20 minutes and then left at normal pressure, 23 캜, and 50% RH for 24 hours.

Thereafter, the active energy rays-curable pressure-sensitive adhesive layer was irradiated with an active energy ray over the plastic plate under the same conditions as in Test Example 1 to irradiate the active energy rays to form a pressure-sensitive adhesive layer after curing.

(%) Was measured in accordance with JIS K7136: 2000 using a haze meter (product name: &quot; NDH2000 &quot; manufactured by Nippon Denshoku Kogyo Co., Ltd.) for the laminate after irradiation with active energy rays. The results are shown in Table 2 as a haze value (%) before the durability test according to the composition A.

Next, the laminate after irradiation with active energy rays was stored for 1000 hours (durability test) under the conditions of 85 ° C and 85% RH under a humid condition, and then left standing at room temperature and normal humidity at 23 ° C and 50% RH for 24 hours. The haze value (%) of the laminate was measured in the same manner as described above. The results are shown in Table 2 as a haze value (%) after the durability test according to the composition A.

Based on the above results, the haze value (%) after the durability test was subtracted from the haze value (%) before the durability test to calculate the difference. The results are shown in Table 2 as the difference (point) between the haze values before and after the durability test according to the composition A.

Further, on the basis of the difference (point) between the haze values before and after the calculated endurance test, the anti-wet heat whitening performance was evaluated based on the following criteria. The results are shown in Table 2 as anti-wet heat whitening properties according to composition A.

 ?: Difference in haze value is less than 1.5 points

 ○: Difference in haze value between 1.5 points and 8.0 points

 X: Difference in haze value, 8.0 points or more

In addition, the post-curing pressure-sensitive adhesive layer in which the evaluation of anti-wet heat whitening property is evaluated as &quot; &quot; indicates that no whitening is observed at all and can be used satisfactorily for a display body or the like. In the cured pressure-sensitive adhesive layer of &quot;? &Quot;, whitening is observed, but it can be said that the pressure-sensitive adhesive layer can also be used for a display or the like. The pressure-sensitive adhesive layer after the cure of &quot; X &quot; is whitened and is not suitable for use on a display or the like.

A plastic plate D (containing an ultraviolet absorber) having a thickness of 0.7 mm and laminated with a polymethyl methacrylate resin (PMMA) layer on a polycarbonate resin (PC) plate was laminated on a polycarbonate resin (Constitution B) in which a 2.0 mm-thick plastic plate F (containing an ultraviolet absorber) in which a polymethyl methacrylate (PMMA) layer was laminated on a PC plate was prepared. The haze value (%) before the durability test and the haze value (%) after the durability test were measured for the laminate according to this composition B, and the difference in haze value before and after the durability test Point) was calculated, and the anti-wet heat resistance was evaluated. These results are shown in Table 2.

[Test Example 9] (Measurement of light transmittance)

The light transmittance (%) of the plastic plate (UV cut) containing the ultraviolet absorber used in Test Examples 7 and 8 was measured using a haze meter (product name: NDH5000, manufactured by Nippon Denshoku Chemical Co., Ltd.) according to JIS K7361-1: 1997 . Table 3 shows the measurement results of the light transmittance at a wavelength of 360 nm and the light transmittance at a wavelength of 390 nm.

[Table 1]

[Table 2]

[Table 3]

As can be seen from Table 2, the cured pressure-sensitive adhesive layer formed by using the pressure-sensitive adhesive sheet obtained in the examples was excellent in blister resistance and anti-wet heat resistance even when it was placed under severe high temperature and high humidity conditions.

INDUSTRIAL APPLICABILITY The pressure-sensitive adhesive sheet of the present invention can be suitably used for bonding a protective panel made of a plastic plate containing an ultraviolet absorber to a display body constituting member in a display body of a car navigation system, for example.

1: Pressure sensitive adhesive sheet
11: Pressure-sensitive adhesive layer
12a, 12b: peeling sheet
2:
11 ': Pressure-sensitive adhesive layer after curing
21: first display body constituting member
22: second display body constituting member
3: Printing layer

Claims (10)

A pressure sensitive adhesive sheet comprising a display body constituting member and a pressure sensitive adhesive layer for bonding other display body constituting members,
At least one of the one display body constituting member and the other display body constituting member is made of a plastic plate,
Wherein the pressure-sensitive adhesive constituting the pressure-
(Meth) acrylic acid ester polymer (A) containing 10 mass% or more and 50 mass% or less of a monomer having a hydroxyl group in the molecule as a monomer constituting the polymer,
A cross-linking agent (B)
An active energy ray-curable component (C)
A photopolymerization initiator (D) having an absorbance at a wavelength of 390 nm of 0.3 or more in an acetonitrile solution having a concentration of 0.1%
(B), and a crosslinking structure obtained by crosslinking the (meth) acrylic acid ester polymer (A) via the crosslinking agent (B) and a crosslinking structure obtained by crosslinking the active energy ray- The photopolymerization initiator (D), which is an active energy ray-curable pressure-sensitive adhesive
Wherein the pressure-sensitive adhesive sheet is a pressure-sensitive adhesive sheet. The method according to claim 1,
Wherein the plastic sheet contains an ultraviolet absorber. The method according to claim 1,
Wherein the active energy ray-curable pressure-sensitive adhesive has a gel fraction of 30% or more and 70% or less. The method according to claim 1,
Two peeling sheets,
Wherein the pressure-sensitive adhesive layer (2) sandwiched between the peeling sheet (2) and the peeling sheet
And a pressure-sensitive adhesive sheet. One display body constituting member,
Another display body constituting member,
A pressure-sensitive adhesive layer after the curing of the one display body constituting member and the other display body constituting member
And a display body,
At least one of the one display body constituting member and the other display body constituting member is made of a plastic plate,
Wherein the cured pressure-sensitive adhesive layer is a cured pressure-sensitive adhesive layer which is obtained by curing the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet according to any one of claims 1 to 4 with active energy rays
. 6. The method of claim 5,
Wherein the gel fraction of the pressure-sensitive adhesive layer after curing is 40% or more and 95% or less. 6. The method of claim 5,
The plastic plate has a thickness of 100 占 퐉 and a water vapor transmission rate of not less than 0.001 g / (m ∙ 24 h 揃 100 袖 m), 100 g / (m 揃 24 h 揃 100 袖 m) measured in accordance with JIS K7129 under the conditions of 40 캜 and 90% By mass or less. 6. The method of claim 5,
Wherein the one display member constituting member has a vapor transmissivity of not less than 0.001 g / (m 2 · 24h) and not more than 100 g / (m 2 · 24h) measured in accordance with JIS K7129 under conditions of 40 ° C. and 90% RH,
Wherein the other display body constituting member has a vapor transmissivity measured according to JIS K7129 under the conditions of 40 DEG C and 90% RH of 0.001 g / (m &lt; 2 &gt;
. A laminate comprising one display body constituting member and another display body constituting member laminated via a pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet according to any one of claims 1 to 4 was produced,
The pressure sensitive adhesive layer of the laminate is irradiated with an active energy ray to cure the pressure sensitive adhesive layer to obtain a pressure-sensitive adhesive layer after curing
&Lt; / RTI &gt; 10. The method of claim 9,
Wherein the active energy ray is irradiated to the pressure-sensitive adhesive layer over a display member constituted of a plastic plate containing an ultraviolet absorber.

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