JP2014156565A - Curable resin composition, tacky layer-fitted transparent surface material, and laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curable resin composition for forming a laminar portion which can form a laminate capable of abating a stress impressed onto a surface material and unlikely to entail, even after long-term storage, residual gaps in the interface of the surface material and tacky layer.SOLUTION: A curable resin composition is a curable resin composition for forming the laminar portion 18 of a tacky layer 14 possessing a laminar portion 18 spread along the surface of a transparent surface material 10 and a dam-shaped portion 20 surrounding the periphery of the laminar portion 18 and including an oligomer (A) which is a urethane acrylate oligomer having a number-average molecular weight of 1,000-100,000 in a state where the average number of curable functional groups is 1.8-4, monomers (B) consisting of one or more types of monomers having molecular weights of 125-600 and bearing curable functional group numbers of 1-3 and including a hydroxyl group-containing monomer (B1), and an oligomer (C) having a number-average molecular weight of 1,000-20,000 and bearing a curable functional group number of 0.5-1.

Description

  The present invention relates to a curable resin composition, a transparent surface material with an adhesive layer, and a laminate.

As a method of using a laminate having an adhesive layer between a pair of face materials, a display device in which a protective plate is bonded to the surface of a display panel via an adhesive layer is known. As a manufacturing method of the laminate, a transparent surface material with an adhesive layer in which an adhesive layer is formed on the surface of a surface material to be a protective plate is manufactured in advance, and the transparent surface material with the adhesive layer and a display panel are obtained. The method of bonding a face material so that an adhesion layer may touch a display panel is mentioned.
The adhesive surface layer with adhesive layer and the adhesive layer of the laminate have a layered portion extending along the surface of the surface material and a weir-like portion surrounding the periphery of the layered portion, and the layered portion is curable. What consists of hardened | cured material of the curable resin composition containing a compound and a non-curable oligomer is known (refer patent document 1, 2).

For example, as a method of bonding the display panel and the transparent surface material with the adhesive layer that has been manufactured in advance, after bonding the display panel and the transparent surface material with the adhesive layer in a reduced pressure atmosphere, There is a method to return to atmospheric pressure. When the display panel and the transparent surface material with the adhesive layer are bonded in a reduced pressure atmosphere, a gap is generated at the interface between the display panel and the adhesive layer. However, when the bonded display panel and the transparent surface material with the adhesive layer are returned to the atmospheric pressure atmosphere, the pressure difference between the pressure in the gap (still reduced pressure) and the pressure applied to the adhesive layer (atmospheric pressure) As a result, the volume of the void is reduced and the void disappears.
As another method of obtaining a laminate, a method of obtaining a laminate by applying an uncured resin composition to be an adhesive layer on a face material and subsequently laminating a face material to be a display panel and curing the adhesive layer There is also.

When the curable resin composition forming the layered portion contains a non-curable oligomer that does not participate in the curing reaction, the fluidity of the layered portion formed is higher than when the non-curable oligomer is not included. . Therefore, the cured product forming the layered portion easily flows into the gap, and the gap generated at the interface between the adhesive layer and the display panel during bonding disappears in a short time.
Moreover, the layer part of the adhesion layer becomes low-elasticity by containing the non-curable oligomer. Therefore, the stress applied to the display panel bonded to the adhesive layer is small, and display unevenness of the display device is suppressed.

International Publication No. 2011/158839 International Publication No. 2012/077726

  However, after forming a pressure-sensitive adhesive layer of a laminate or a transparent surface material with a pressure-sensitive adhesive layer, when a predetermined time elapses at room temperature or in a high-temperature environment, the display panel bonded at the pressure-sensitive adhesive layer location corresponding to the boundary region between the layered portion and the weir-shaped portion There was a problem of poor bonding such as voids occurring at the interface between the adhesive layer and the adhesive layer.

  The present invention can reduce stress due to curing shrinkage applied to the face material, and a gap remains at the interface between the face material such as a bonded display panel and the adhesive layer even after a predetermined time has elapsed after the formation of the adhesive layer. The present invention provides a curable resin composition for forming a layered portion, which can form a transparent surface material with an adhesive layer and a laminate that hardly cause poor bonding. Moreover, this invention provides the transparent surface material with an adhesion layer and laminated body which were formed using this curable resin composition.

When the present inventors examined the problem of the bonding failure in detail, it was found that the following were the factors. Specifically, the non-curable oligomer diffused and moved over time from the layered portion to the weir-shaped portion due to the concentration difference of the non-curable oligomer between the adhesive layers forming the layered portion and the weir-shaped portion. As a result, at the interface between the layered portion and the dammed portion, the volume of the dammed portion increases and expands, while the volume of the layered portion decreases and shrinks, the surface of the layered portion deforms into a concave shape, and the surface of the dammed portion deforms into a convex shape. As a result, a step is generated on the surface of the adhesive layer. As a result, at the interface between the adhesive layer and the display panel when bonding to a face material such as a display panel, a bonding failure such as a gap was generated at the portion corresponding to the interface between the layered portion and the weir-shaped portion was caused to remain. .
The present invention and the like are further studied, and as a curable resin composition for forming a layered portion, a curable resin composition containing an oligomer (C) having an average number of curable functional groups of 0.5 to 1 is used. The inventors have found that, while obtaining the same effect as the non-curable oligomer, it is possible to suppress the generation of voids at the interface between the adhesive layer and the face material bonded even when a predetermined time has elapsed after formation of the adhesive layer.

The curable resin composition of the present invention is an adhesive layer that bonds a pair of face materials, and has a layered portion that extends along the surface of the face material, and a weir-like portion that surrounds the periphery of the layered portion. It is a curable resin composition for forming the layered part in, and contains the following oligomer (A), the following monomer (B) and the following oligomer (C).
Oligomer (A): An oligomer having a number average molecular weight of 1,000 to 100,000 and an average number of curable functional groups of 1.8 to 4.
Monomer (B): A monomer comprising at least one monomer having a molecular weight of 125 to 600 and a number of curable functional groups of 1 to 3, and including at least one monomer (B1) having a hydroxyl group.
Oligomer (C): An oligomer having a number average molecular weight of 1,000 to 20,000 and an average number of curable functional groups of 0.5 to 1.

The curable resin composition of the present invention preferably further contains a photopolymerization initiator (E1).
Moreover, it is preferable that the curable resin composition of this invention contains the following non-curable oligomer (D) further.
Non-curable oligomer (D): an oligomer which does not undergo a curing reaction with the oligomer (A), monomer (B) and oligomer (C) at the time of curing, has a hydroxyl group, and has a molecular weight per hydroxyl group of 400 to 8,000. .

Moreover, it is preferable that the ratio of the said oligomer (C) with respect to the sum total (100 mass%) of the said oligomer (C) and the said non-curable oligomer (D) is 50-100 mass%.
The curable functional group is preferably an acryloyloxy group or a methacryloyloxy group.
Further, the oligomer (A) is a urethane obtained by reacting a polyol and a polyisocyanate to obtain a prepolymer having an isocyanate group at the terminal, and then reacting the following monomer (a1) with the isocyanate group of the prepolymer. After the oligomer (C) is a acrylate oligomer and the monool and polyisocyanate are reacted to obtain a prepolymer having an isocyanate group only at one end, the following monomer (c1) is added to the isocyanate group of the prepolymer. It is preferable that it is an oligomer obtained by reacting.
Monomer (a1): A monomer having a molecular weight of 125 to 600, one or more acryloyloxy groups, and one group that reacts with an isocyanate group.
Monomer (c1): A monomer having a molecular weight of 125 to 600, having one or more acryloyloxy groups and one group that reacts with an isocyanate group.

  Moreover, the said oligomer (A) is 6-80 mass% with respect to the sum total (100 mass%) of the said oligomer (A), a monomer (B), and an oligomer (C), and the said monomer (B) is 3-70 mass. %, And the oligomer (C) is preferably 10 to 70% by mass.

  The transparent surface material with an adhesive layer of the present invention has a transparent surface material and an adhesive layer provided on the surface of the transparent surface material, and the adhesive layer extends along the surface of the transparent surface material. And a weir-like part surrounding the periphery of the layered part, and the layered part is made of a cured product of the curable resin composition of the present invention.

  The laminate of the present invention has a pair of face materials and an adhesive layer provided so as to be in contact with two faces facing each other, and the adhesive layer is along the surface of the face material. It has a layered portion that spreads and a weir-shaped portion surrounding the periphery of the layered portion, and the layered portion is made of a cured product of the curable resin composition of the present invention.

  The curable resin composition of the present invention and the obtained transparent surface material or laminate with an adhesive layer can reduce stress applied to the surface material, such as a display panel that is bonded even after a predetermined time has elapsed after formation of the adhesive layer. Bonding defects such as voids remaining at the interface between the face material and the adhesive layer are unlikely to occur.

It is sectional drawing which shows an example of the transparent surface material with the adhesion layer of this invention.

In this specification, “transparent” means that the whole or a part of the display image of the display panel is optically distorted after the face material and the display surface of the display panel are bonded through the adhesive layer without any gap. It means an aspect that can be seen through the face material without receiving it. Therefore, even if part of the light incident on the face material from the display panel is absorbed and reflected by the face material, or the visible material has a low visible ray transmittance due to a change in optical phase, etc. If the display image on the display panel can be visually recognized without optical distortion through the material, it can be said to be “transparent”.
The “curable functional group” means a functional group having a radical polymerizable unsaturated bond. “(Meth) acrylate” means a general term for acrylate and methacrylate.
Further, the average number of curable functional groups of the oligomer means the average number of curable functional groups per molecule in 1 mol of the oligomer. The average number of curable functional groups of the oligomer is calculated from the blend of raw materials at the time of production of the oligomer.
The number average molecular weight of the oligomer in the present invention is a polystyrene-equivalent number average molecular weight obtained by gel permeation chromatography (GPC) measurement. In the GPC measurement, when a peak of an unreacted low molecular weight component (monomer or the like) appears, the number average molecular weight is determined by excluding the peak.

≪Curable resin composition≫
The curable resin composition of the present invention forms a layered portion of an adhesive layer having a layered portion that extends along the surface of the face material, and a weir-like portion that surrounds the periphery of the layered portion, by bonding a pair of face materials together It is the curable resin composition for doing. Hereinafter, the curable resin composition for forming the layered portion is referred to as a first composition, and the curable resin composition for forming the weir-like portion is referred to as a second composition.

The 1st composition in this invention is a composition which uses the oligomer (A), monomer (B), and oligomer (C) which are mentioned later as an essential component.
The first composition may be a photocurable resin composition or a thermosetting resin composition. The first composition is preferably a photocurable resin composition in which a photopolymerization initiator (E1) is further blended from the viewpoint that it can be cured at a low temperature and has a high curing rate. In addition, if the first composition is a photocurable resin composition, a high temperature is not required for curing, so that there is little risk of damage to the display panel or the like due to high temperatures.
Moreover, it is preferable that the non-curable oligomer (D) is further blended in the first composition. Moreover, the 1st composition may be mix | blended with the additive as needed.

(Oligomer (A))
The oligomer (A) is an oligomer having a number average molecular weight of 1,000 to 100,000 and an average number of curable functional groups of 1.8 to 4.
The oligomer (A) preferably has 2 or more and 4 or less curable functional groups in one molecule, but in the production process of the oligomer (A), a by-product other than the oligomer having the desired number of curable functional groups. May occur. The oligomer (A) has 1.8 to 4 curable functional groups, including the by-product.
The number average molecular weight of the oligomer (A) is 1,000 to 100,000, and preferably 10,000 to 70,000. When the number average molecular weight of the oligomer (A) is in the above range, it is easy to adjust the viscosity of the first composition to the above range, and it is easy to obtain a cured film having no remaining bubbles.

As the curable functional group of the oligomer (A), an acryloyloxy group or a methacryloyloxy group is preferable, and an acryloyloxy group is particularly preferable.
The average number of curable functional groups of the oligomer (A) is 1.8 to 4 and preferably 1.8 to 3 from the viewpoint of the curability of the first composition and the mechanical properties of the layered portion.
The oligomer (A) may be one type or two or more types.

As the oligomer (A), a urethane oligomer is preferable, and the following oligomer (A1) is particularly preferable.
Oligomer (A1): A urethane acrylate oligomer obtained by reacting a polyol and polyisocyanate to obtain a prepolymer having an isocyanate group at the terminal, and then reacting the isocyanate group of the prepolymer with the following monomer (a1).
Monomer (a1): A monomer having a molecular weight of 125 to 600, one or more acryloyloxy groups, and one group that reacts with an isocyanate group.

Examples of the monomer (a1) include a monomer having an active hydrogen group (hydroxyl group, amino group, etc.) and an acryloyloxy group.
Specific examples of the monomer (a1) include hydroxyalkyl acrylates having a C2-C6 hydroxyalkyl group (2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, etc.). ) And the like.
The monomer (a1) to be reacted with the prepolymer is preferably a hydroxyalkyl acrylate having a C2-C4 hydroxyalkyl group.

  As the polyol and polyisocyanate, known compounds can be used. For example, polyol (i), diisocyanate (ii) and the like described as a raw material of the urethane oligomer (a) described in International Publication No. 2009/016943. Can be mentioned. That is, polyol (i) having an average of 1.8 to 4 hydroxyl groups per molecule and non-yellowing diisocyanate (ii) can be mentioned.

The oligomer (A) having an average number of curable functional groups in the above range can be obtained by adjusting the raw material blending ratio during the production of the oligomer (A). For example, in the case of the oligomer (A1), it can be obtained by the following method.
(I) In the case of an oligomer (A1) having an average of 1.8 to 2 curable functional groups An average of 1.8 to 2 functional polyols and a bifunctional polyisocyanate are reacted to form an isocyanate group at the terminal. After obtaining a prepolymer having 1.8 to 2 on average, a monomer (a11) having one curable functional group and one hydroxyl group in one molecule has a ratio of the number of moles of isocyanate group / hydroxyl group of 1/1. The method of making it react.
(Ii) In the case of an oligomer (A1) having an average of 2 to 4 curable functional groups A prepolymer having an average of two isocyanate groups at the terminal by reacting an average bifunctional polyol and a bifunctional polyisocyanate. After obtaining the polymer, the monomer (a12) having one hydroxyl group and one or more curable functional groups in one molecule has an isocyanate group / hydroxyl mole ratio ratio of 1/1, and the curable functional group is an average. The method of making it react so that it may become 2-4 pieces.

Specific examples of the polyol include polyoxyalkylene polyol (polyoxyethylene glycol, polyoxypropylene polyol, etc.), polyester polyol, and polycardnate polyol. Among these, as the polyol, polyoxyalkylene polyol is preferable, and polyoxypropylene polyol is more preferable. Moreover, if a polyoxyalkylene polyol having an oxyalkylene group containing an oxypropylene group and an oxyethylene group is used, the compatibility with the other components of the first composition can be increased, which is more preferable. Moreover, if it is a polyoxyalkylene polyol, a highly flexible hardened | cured material will be easy to be obtained also in a low temperature range, and especially the polyoxyalkylene polyol comprised from an oxyethylene group and an oxypropylene group is preferable.
The polyol may be one kind or two or more kinds.

The polyisocyanate is preferably at least one diisocyanate selected from the group consisting of aliphatic diisocyanates, alicyclic diisocyanates and non-yellowing aromatic diisocyanates.
Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate, and 2,4,4-trimethyl-hexamethylene diisocyanate.
Examples of the alicyclic polyisocyanate include isophorone diisocyanate and methylene bis (4-cyclohexyl isocyanate).
Examples of the non-yellowing aromatic diisocyanate include xylylene diisocyanate.
The polyisocyanate may be one type or two or more types.

  20-90 mass% is preferable and, as for the ratio of the oligomer (A) with respect to the sum total (100 mass%) of the oligomer (A) and monomer (B) in a 1st composition, 30-80 mass% is more preferable. If the ratio of the oligomer (A) is at least the lower limit value, the heat resistance of the layered portion will be good. If the ratio of this oligomer (A) is below an upper limit, the curability of a 1st composition and the adhesiveness of a face material and a layer part will become favorable.

(Monomer (B))
The monomer (B) is a monomer comprising at least one monomer having a molecular weight of 125 to 600 and a number of curable functional groups of 1 to 3, and including at least one monomer (B1) having a hydroxyl group. By including the monomer (B1), good adhesion between the face material and the layered portion can be obtained.
A hydroxyl group derived from the monomer (B) remains in the layered portion made of the cured product of the first composition. The presence of such a hydroxyl group contributes to the dispersion stabilization of the non-curable oligomer (D) in the layered portion when the non-curable oligomer (D) described later is blended in the first composition.

The molecular weight of the monomer (B) is 125 to 600, preferably 140 to 400. The smaller the molecular weight of the monomer (B), the better the adhesion between the face material and the layered portion. If the molecular weight of a monomer (B) is more than a lower limit, volatilization of the monomer (B) at the time of manufacturing a transparent surface material with adhesive layer or a laminate by the method described later can be suppressed.
The monomer (B) may be one type or two or more types.

The number of curable functional groups of the monomer (B) is 1 to 3, and preferably 1 to 2. As the monomer (B), it is preferable to use a monomer having one curable functional group and a monomer having two or more curable functional groups.
Examples of the curable functional group of the monomer (B) include an acryloyloxy group and a methacryloyloxy group. The curable functional group of the monomer (B) is preferably an acryloyloxy group or a methacryloyloxy group from the viewpoint that a curing rate is high and a highly transparent layered part is obtained. The oligomer (A), the monomer (B), A methacryloyloxy group is particularly preferred because the difference in reactivity between the curable functional groups is reduced and a homogeneous layered portion is obtained.

The number of hydroxyl groups in the monomer (B1) is preferably 1 or 2.
Examples of the monomer (B1) having one hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6- Examples thereof include hydroxyhexyl methacrylate.
Examples of the monomer (B1) having two hydroxyl groups include glycerin monomethacrylate and 2,3-dihydroxypropyl acrylate.
The monomer (B1) is preferably a hydroxy methacrylate having a hydroxyalkyl group having 1 to 2 hydroxyl groups and 3 to 8 carbon atoms (2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, etc.). 2-hydroxybutyl methacrylate is particularly preferred.
The monomer (B1) may be one type or two or more types.

The curable resin composition of the present invention may further contain the following monomer (B2).
Monomer (B2): A monomer having 1 to 3 curable functional groups, a molecular weight of 125 to 600, and no hydroxyl group.

As the monomer (B2), the following monomer (B21) is preferable. When the content of the monomer (B21) is larger than the content of the monomer (B1) by mass ratio, after bonding the surface material to be bonded such as a display panel and the transparent surface material with an adhesive layer in a reduced pressure atmosphere When this is returned to the atmospheric pressure atmosphere, the time until the voids generated in the adhesive layer disappear tends to be shortened. On the other hand, when the monomer (B21) is contained, the time required for curing the first composition tends to be long.
Monomer (B21): an alkyl methacrylate having no hydroxyl group and having an alkyl group having 8 to 22 carbon atoms.

Examples of the monomer (B21) include n-dodecyl methacrylate, n-octadecyl methacrylate, n-behenyl methacrylate, and the like. As the monomer (B21), n-dodecyl methacrylate and n-octadecyl methacrylate are preferable.
The monomer (B2) may be one type or two or more types.

10-80 mass% is preferable and, as for the ratio of the monomer (B) with respect to the sum total (100 mass%) of the oligomer (A) and monomer (B) in a 1st composition, 20-70 mass% is more preferable.
10-60 mass% is preferable and, as for the ratio of the monomer (B1) with respect to the sum total (100 mass%) of the oligomer (A) and monomer (B) in a 1st composition, 20-50 mass% is more preferable. If the ratio of the monomer (B1) is at least the lower limit value, the storage stability of the first composition and the adhesion between the face material and the layered part will be good.
10-50 mass% is preferable and, as for the ratio of the monomer (B2) with respect to the sum total (100 mass%) of the oligomer (A) and monomer (B) in a 1st composition, 20-40 mass% is more preferable. If the ratio of the monomer (B2) is at least the lower limit value, the effect of adding the monomer (B2) can be sufficiently obtained.

In addition, in the synthesis | combination of an oligomer (A1), since the monomer (a1) reacted with the isocyanate group of a prepolymer exists as a part of oligomer (A), it is included in the ratio of the monomer (B) in a 1st composition. Absent. On the other hand, in the synthesis of the oligomer (A1), when the monomer (which does not react with the prepolymer) added as a diluent at the time of synthesis or after synthesis of the oligomer (A1) corresponds to the monomer (B) The monomer is also included in the ratio of the monomer (B) in the first composition.
The same applies to the handling of the monomer used in the synthesis of the oligomer (C).

(Oligomer (C))
The oligomer (C) is an oligomer having a number average molecular weight of 1,000 to 20,000 and an average number of curable functional groups of 0.5 to 1.
The number average molecular weight of the oligomer (C) is 1,000 to 20,000, preferably 2,000 to 10,000. When the number average molecular weight of the oligomer (C) is in this range, the viscosity of the first composition is easily adjusted to the above range.
The blending of the oligomer (C) into the first composition can be achieved by shortening the time required for disappearance of voids generated at the interface between the adhesive layer and the display panel during pasting with the display panel, etc. This contributes to suppression of display unevenness of a display device which is a laminate of display panels.

Examples of the curable functional group possessed by the oligomer (C) include an acryloyloxy group and a methacryloyloxy group. The curable functional group of the oligomer (C) is preferably an acryloyloxy group or a methacryloyloxy group from the viewpoint that a curing rate is high and a highly transparent layered portion is obtained. The oligomer (C), the monomer (B), The acryloyloxy group is particularly preferable because the difference in reactivity between the curable functional groups is reduced and a homogeneous layered portion is obtained.
The average number of curable functional groups of the oligomer (C) is 0.5 to 1 and preferably 0.7 to 1 from the viewpoint of the curability of the first composition and the mechanical properties of the layered portion. When the number of curable functional groups exceeds 1, an oligomer having crosslinkability is obtained, and the elastic modulus of the cured product of the curable resin composition is easily increased, so that the stress applied to the display panel bonded to the adhesive layer is large, and the display device Display irregularities easily. In addition, the fluidity of the layered portion is lost, and voids generated at the interface between the adhesive layer and the display panel during bonding are likely to remain. Therefore, it is preferable to select a raw material at the time of producing the oligomer (C) so that a reaction product exceeding 1 is not included.

As the oligomer (C), the following oligomer (C1) is preferable.
Oligomer (C1): obtained by reacting monool and polyisocyanate to obtain a prepolymer having an isocyanate group only at one end, and then reacting the following monomer (c1) with the isocyanate group of the prepolymer. A polyurethane monoacrylate oligomer having an average number of curable functional groups of 0.5 to 1.
Monomer (c1): A monomer having a molecular weight of 125 to 600, having one or more acryloyloxy groups and one group that reacts with an isocyanate group.

The average number of curable functional groups of the oligomer (C) can be controlled to 0.5 to 1 by adjusting the raw material blending ratio during the production of the oligomer (C).
For example, it can be produced by the following method.
(Iii) Monool and diisocyanate are reacted at a ratio in which the ratio of the number of moles of isocyanate group / hydroxyl group is 1.0 to 2.0, and an average of 0.5 to 1.0 After obtaining the prepolymer having an isocyanate group, the ratio of the number of moles of the isocyanate group of the prepolymer and the monomer (c11) having one acryloyloxy group reacting with the isocyanate group / the group reacting with the isocyanate group is 1 /. The method of making it react so that it may become 1.
(Iv) reacting a monool with a compound having one acryloyloxy group and one isocyanate group in one molecule at a ratio of the isocyanate group / hydroxyl mole ratio of 0.5 to 1.0. A method for obtaining a compound having an average of 0.5 to 1.0 acryloyloxy groups in one molecule.

Examples of the polyol and polyisocyanate used for the oligomer (C) are the same as those described above for the oligomer (A1), and preferred embodiments are also the same. The monomer (c1) is the same as the monomer (a1) described above, and the preferred embodiment is also the same.
The oligomer (C) may be one type or two or more types.

  In the present invention, the oligomer (A) and the oligomer (C) are the same from the viewpoint of stabilizing the mixed state of the first composition before curing and suppressing the separation of the oligomer (C) from the layered portion after curing. It is preferable to have a molecular chain having a structure or a similar structure. In the present invention, it is more preferable that the oligomer (A) is the oligomer (A1) and the oligomer (C) is the oligomer (C1).

  As for the ratio of the oligomer (C) in a 1st composition (100 mass%), 10-70 mass% is preferable. If the ratio of the oligomer (C) is at least the lower limit value, it is difficult for voids to remain between the layered portion and the face material. If the ratio of this oligomer (C) is below an upper limit, the curability of a 1st composition and the adhesiveness of a face material and a layer part will become favorable.

(Non-curable oligomer (D))
The non-curable oligomer (D) is an oligomer which does not undergo a curing reaction with the oligomer (A), the monomer (B) and the oligomer (C) at the time of curing, has a hydroxyl group, and has a molecular weight per hydroxyl group of 400 to 8,000. is there.
When the non-curable oligomer (D) is included in the first composition, the fluidity of the first composition is increased and the elastic modulus of the layered portion is reduced. Therefore, a non-curable oligomer (D) is a surface material to be bonded and an adhesive layer when the transparent surface material with the adhesive layer and the surface material to be bonded are bonded under a reduced pressure atmosphere and then returned to the atmospheric pressure atmosphere. This contributes to shortening of the time required for the gap generated at the interface to disappear. In addition, the non-curable oligomer (D) is formed by applying the first composition on the face material to form an uncured layered portion, and then further applying the face material on the uncured layered portion in a reduced-pressure atmosphere. It can laminate | stack and return to atmospheric pressure atmosphere, and can suppress the stress concerning a face material when a non-hardened layered part is hardened. The non-curable oligomer (D) can easily obtain the above effect in a small amount, but when it is made into a layered portion, it diffuses into the weir-like portion, so that deformation (step) occurs at the interface between the layered portion and the weir-like portion. Therefore, it is preferable to use within the range of the amount described later.

The average number of hydroxyl groups of the non-curable oligomer (D) is preferably 0.8 to 3, and more preferably 1.8 to 2.3.
The number average molecular weight per hydroxyl group of the non-curable oligomer (D) is 400 to 8,000. If the number average molecular weight per hydroxyl group is 400 or more, the polarity of the non-curable oligomer (D) does not become too high and good compatibility with the oligomer (A), monomer (B) and oligomer (C). Is easy to obtain. If the number average molecular weight per hydroxyl group is 8,000 or less, in the layered part after curing due to the interaction between the hydroxyl group derived from the monomer (B1) and the hydroxyl group of the non-curable oligomer (D) Therefore, the effect of stabilizing the dispersion of the non-curable oligomer (D) can be easily obtained. Such an interaction is presumed to involve hydrogen bonding.
The non-curable oligomer (D) may be one type or two or more types.

Examples of the non-curable oligomer (D) include a high molecular weight polyol. As the non-curable oligomer (D), polyoxyalkylene polyol, polyester polyol, and polycarbonate polyol are preferable. When the oligomer (A) is a urethane acrylate using a polyoxyalkylene polyol as a raw material, the non-curable oligomer (D) is more preferably a polyoxyalkylene polyol because the compatibility is better.
Examples of the polyoxyalkylene polyol include polyoxyalkylene diols such as polyoxyethylene glycol, polyoxypropylene diol, polyoxypropylene triol, and polyoxytetramethylene glycol.
The number average molecular weight per hydroxyl group of the polyoxyalkylene polyol is 400 to 8,000, preferably 600 to 5,000.

The number average molecular weight of the non-curable oligomer (D) is the average per one molecule of the hydroxyl value P (mg KOH / g) measured according to JIS K1557-1 (2007 edition) and the non-curable oligomer (D). It is a value calculated from the number of hydroxyl groups Q by the following formula (1).
Molecular weight of non-curable oligomer (D) = 56.1 × Q × 1000 / P (1)

  A polyoxyalkylene polyol is preferably used as the non-curable oligomer (D) from the viewpoint that the elastic modulus of the layered portion after curing tends to be lower, and polyoxypropylene polyol is particularly preferable. Further, as the non-curable oligomer (D), a polyoxyalkylene polyol having an oxypropylene group and an oxyethylene group may be used.

Moreover, in this invention, the point which stabilizes the mixing state of the 1st composition before hardening and suppresses a non-hardening oligomer (D) isolate | separating from the layered part after hardening, an oligomer (A) or an oligomer (C ) And the non-curable oligomer (D) preferably have molecular chains having the same structure or a similar structure.
Specifically, a compound having a hydroxyl group (hereinafter referred to as “hydroxyl group-containing compound”) is used as a raw material for the oligomer (A) or oligomer (C) in the first composition, and the same hydroxyl group-containing compound is used as a non-polymer. It is preferable to use it as a curable oligomer (D).
In the first composition, oligomer (A) or oligomer (C) is a urethane acrylate oligomer synthesized using polyoxyalkylene polyol and polyisocyanate as raw materials, and non-curable oligomer (D) is polyoxyalkylene polyol. It is particularly preferable from the viewpoint of compatibility.

Even when the hydroxyl group-containing compound used as the raw material for the oligomer (A) or oligomer (C) is not the same as the hydroxyl group-containing compound used as the non-curable oligomer (D), these hydroxyl group-containing compounds are repeating units having a common molecular chain. It is preferable that they have a partially common structure and have the same polarity. If the oligomer (A), the oligomer (C) and the non-curable oligomer (D) partially have the same molecular structure, the compatibility of the non-curable oligomer (D) in the composition is more Rise.
Examples of the method for adjusting the polarity of the hydroxyl group-containing compound include a method for introducing a polar group and a method for producing a hydroxyl group-containing compound having an oxyalkylene group containing an oxypropylene group and an oxyethylene group. Introducing a polar group increases the polarity of the hydroxyl group-containing compound. Moreover, if it is a hydroxyl-containing compound which has an oxyalkylene group containing an oxypropylene group and an oxyethylene group, the polarity of a hydroxyl-containing compound will go up. These methods may be used in combination.

Preferred combinations in the case where the hydroxyl group-containing compound used as the raw material for the oligomer (A) or oligomer (C) and the hydroxyl group-containing compound used as the non-curable oligomer (D) are not the same include the following combinations.
The oligomer (A) or oligomer (C) is a urethane acrylate oligomer synthesized using a polyoxypropylene polyol in which a part of the oxypropylene group is substituted with an oxyethylene group and a polyisocyanate as raw materials, and is non-curable. A combination in which the oligomer (D) is a polyoxypropylene polyol having no oxyethylene group, and the molecular weight per hydroxyl group is smaller than the polyol used as the oligomer (A).

As a combination of the oligomer (A), oligomer (C) and non-curable oligomer (D) contained in the first composition, the following oligomer (A11), oligomer (C11) and the following non-curable oligomer (D1) are combined. Is most preferred.
Oligomer (A11): obtained by reacting a polyoxyalkylenediol having an oxypropylene group and an oxyethylene group with a polyisocyanate to obtain a prepolymer having an isocyanate group at the terminal, and then reacting with the monomer (a1). Polyurethane acrylate oligomer.
Oligomer (C11): After reacting a polyoxyalkylene monool having an oxypropylene group and an oxyethylene group with a polyisocyanate to obtain a prepolymer having an isocyanate group only at one end, the monomer (c1) is used. A polyurethane monoacrylate oligomer obtained by reaction.
Non-curable oligomer (D1): Polyoxyalkylene diol having the same oxypropylene group and oxyethylene group as the raw material of the oligomer (A11).

Moreover, as a combination of the oligomer (A) and non-curable oligomer (D) contained in the first composition, a combination of the oligomer (A11), the oligomer (C11) and the following non-curable oligomer (D2) is also preferable. .
Non-curable oligomer (D2): a polyoxypropylene diol having an oxypropylene group and having a molecular weight smaller than that of the raw material of the oligomer (A11).

  When the non-curable oligomer (D) is used, the content of the non-curable oligomer (D) in the first composition (100% by mass) is preferably 1 to 35% by mass. If content of a non-curable oligomer (D) is more than a lower limit, a space | gap will not remain easily between an adhesion layer and a face material. If content of a non-curable oligomer (D) is below an upper limit, if a layered part fully hardens, it will become easy to exfoliate a protective film from an adhesion layer after hardening.

  Moreover, when using a non-curable oligomer (D), the ratio of the oligomer (C) with respect to the sum total (100 mass%) of the oligomer (C) and non-curable oligomer (D) in a 1st composition is 50 mass%. The above is preferable, and 70% by mass or more is more preferable. If the ratio of the oligomer (C) is equal to or more than the lower limit, it is easy to suppress the generation or remaining of voids between the layered portion and the face material. The upper limit of the ratio of the oligomer (C) is 100% by mass.

The chain transfer agent also contributes to shortening the time until the void generated at the interface between the face material and the adhesive layer disappears.
When the first composition contains no chain transfer agent, contains monomer (B1) and monomer (B2), and the mass ratio of monomer (B2) to monomer (B1) is 0.6 to 2.5, As for content of the non-curable oligomer (D) in a 1st composition (100 mass%), 30-70 mass% is more preferable, and 40-70 mass% is further more preferable.
A 1st composition contains 1 mass part or less chain transfer agent with respect to a total of 100 mass parts of an oligomer (A), a monomer (B), and an oligomer (C), and content of a monomer (B2) is a monomer ( When the amount is less than B1), the content of the non-curable oligomer (D) in the first composition (100% by mass) is preferably 40 to 70% by mass, and more preferably 50 to 70% by mass.
The first composition contains monomer (B1) and monomer (B2), the mass ratio of monomer (B2) to monomer (B1) is 1 to 3, and oligomer (A), monomer (B) and oligomer (C ), The content of the non-curable oligomer (D) in the first composition (100% by mass) is 5 to 55% by mass. Is more preferable, 10-50 mass% is further more preferable, and 35-50 mass% is especially preferable.

  Moreover, since there exists a tendency for a cure rate to become slow when the monomer (B2) or chain transfer agent is contained in the 1st composition, the one where the usage-amount of a monomer (B2) and a chain transfer agent is small is preferable.

In the present invention, the first composition is composed of 6 to 80% by mass of the oligomer (A) and monomer (B) with respect to the total (100% by mass) of the oligomer (A), the monomer (B) and the oligomer (C). Is preferably 3 to 70% by mass, oligomer (C) is preferably 10 to 70% by mass, oligomer (A) is 6 to 60% by mass, monomer (B) is 3 to 55% by mass, and oligomer (C) is It is more preferable that it is 30-70 mass%.
In this invention, when a 1st composition contains a non-curable oligomer (D), it is the sum total (100 mass%) of an oligomer (A), a monomer (B), an oligomer (C), and a non-curable oligomer (D). On the other hand, the oligomer (A) is 6 to 80% by mass, the monomer (B) is 3 to 70% by mass, the oligomer (C) is 5 to 69% by mass, and the non-curable oligomer (D) is 1 to 35% by mass. It is preferable that the oligomer (A) is 6 to 60% by mass, the monomer (B) is 3 to 55% by mass, the oligomer (C) is 15 to 69% by mass, and the non-curable oligomer (D) is 1 to 35% by mass. % Is more preferable.

The viscosity of the first composition is preferably 0.05 to 50 Pa · s, more preferably 1 to 20 Pa · s. If the viscosity of the first composition is 0.05 Pa · s or more, when the layered portion is obtained by the production method described later, the coating shape of the first composition that becomes the layered portion is maintained before the lamination, and the layer is large after the lamination. Even if voids are generated when returned to the atmospheric pressure atmosphere, they tend to become independent voids, and the void volume decreases due to the differential pressure between the pressure in the voids (still under reduced pressure) and the pressure applied to the adhesive layer (atmospheric pressure). Since the voids easily disappear, it is possible to obtain a cured film having no remaining bubbles. If the viscosity of the first composition is 50 Pa · s or less, voids are unlikely to remain between the layered portion and the face material.
The viscosity of the first composition is measured using an E-type viscometer at 25 ° C.

(Photopolymerization initiator (E1))
Examples of the photopolymerization initiator (E1) include acetophenone series, ketal series, benzoin or benzoin ether series, phosphine oxide series, benzophenone series, thioxanthone series, and quinone series. As the photopolymerization initiator (E1), phosphine oxide and thioxanthone photopolymerization initiators are preferable, and phosphine oxide is particularly preferable in terms of suppressing coloring after the photopolymerization reaction.

  Content of the photoinitiator (E1) in a photocurable 1st composition is 0.01-10 mass with respect to a total of 100 mass parts of an oligomer (A), a monomer (B), and an oligomer (C). Part is preferable, and 0.1 to 5 parts by mass is more preferable.

(Additive)
Additives include polymerization inhibitors, photocuring accelerators, chain transfer agents, light stabilizers (ultraviolet absorbers, radical scavengers, etc.), antioxidants, flame retardants, adhesion improvers (silane couplings) Agents, etc.), pigments, dyes and the like. As an additive added to the first composition, a polymerization inhibitor and a light stabilizer are preferable. In particular, the storage stability of the first composition can be improved by including a smaller amount of the polymerization inhibitor than the polymerization initiator, and the molecular weight of the layered portion after curing can be adjusted.

Polymerization inhibitors such as hydroquinone (2,5-di-tert-butylhydroquinone), catechol (p-tert-butylcatechol, etc.), anthraquinone, phenothiazine, hydroxytoluene, etc. are prohibited. Agents.
Examples of the light stabilizer include ultraviolet absorbers (benzotriazole-based, benzophenone-based, salicylate-based, etc.), radical scavengers (hindered amine-based), and the like.
Examples of the antioxidant include phosphorus compounds and sulfur compounds.
The content of the additive in the first composition is preferably 10 parts by mass or less and more preferably 5 parts by mass or less with respect to 100 parts by mass in total of the oligomer (A), the monomer (B) and the oligomer (C). .

The storage shear elastic modulus at 35 ° C. of the layered portion after the first composition is cured is preferably 0.5 to 100 kPa. The lower limit of the storage shear modulus is more preferably 0.8 kPa. The upper limit of the storage shear modulus is more preferably 80 kPa, and even more preferably 70 kPa. If the storage shear modulus is within the above range, after bonding with the surface material to be bonded, the void generated at the interface between the layered portion and the weir-like portion disappears at the interface between the surface material to be bonded and the adhesive layer. It's easy to do. Moreover, in the laminated body obtained by bonding a to-be-bonded surface material and a transparent surface material, a to-be-bonded surface material can be fixed favorably.
The storage shear modulus at 35 ° C. of the layered portion was measured using a rheometer (Modular Rheometer Physica MCR-301, manufactured by Anton Paar), and the gap between the measuring spindle and the translucent plate was measured. Same as thickness, place uncured first composition in the gap, measure the storage shear modulus of the curing process while applying heat and light necessary for curing to the uncured first composition, layered The measured value under the curing conditions when forming the part is defined as the storage shear modulus of the layered part.
The storage shear modulus can be adjusted by the blending amount of the oligomer (C), and the storage shear modulus increases as the amount of the oligomer (C) increases. Furthermore, the storage shear modulus can also be adjusted by blending the non-curable oligomer (D).

≪Transparent surface material with adhesive layer≫
FIG. 1 is a cross-sectional view showing an example of a transparent surface material with an adhesive layer of the present invention.
The transparent surface material 1 with an adhesive layer includes a transparent surface material 10 (protective plate), a light shielding printing portion 12 formed on the peripheral edge of the surface of the transparent surface material 10, and a transparent surface on the side where the light shielding printing portion 12 is formed. The adhesive layer 14 formed on the surface of the material 10 and the peelable protective film 16 (protective material) that covers the surface of the adhesive layer 14 are included.
The transparent surface material 1 with an adhesive layer can manufacture a display apparatus by peeling the protective film 16, and bonding with a display panel.
Although FIG. 1 illustrates the case where the adhesive layer 14 is formed on one side of the transparent surface material 10, the adhesive layer may be formed on both surfaces of the transparent surface material, and in that case, any adhesive layer may be formed. The surface of is also covered with a peelable protective film.

<Transparent surface material>
The transparent surface material 10 is preferably a protective plate that is provided on the image display side of the display panel and protects the display panel.
Examples of the transparent face material 10 include a glass plate and a transparent resin plate. The transparent surface material 10 has not only high transparency with respect to light emitted from the display panel and reflected light, but also light resistance, low birefringence, high planar accuracy, surface scratch resistance, and high mechanical strength. The glass plate is most preferable from the viewpoint of having it. Moreover, it is preferable that the transparent surface material 10 is a glass plate also from the point which permeate | transmits the light for hardening of a photocurable resin composition fully.

Examples of the material of the glass plate include glass materials such as soda lime glass. As the glass plate, a high transmission glass (white plate glass) having a lower iron content and less bluishness is preferable. As the glass plate, tempered glass may be used to increase safety. In particular, when a thin glass plate is used, it is preferable to use a chemically strengthened glass plate.
Examples of the material for the transparent resin plate include highly transparent resin materials (such as polycarbonate and polymethyl methacrylate).

The transparent face material 10 may be subjected to a surface treatment in order to improve the interfacial adhesive force with the adhesive layer 14. Examples of the surface treatment method include a method of treating the surface of the transparent face material 10 with a silane coupling agent, a method of forming a silicon oxide thin film by an oxidation flame using a frame burner, and the like.
In order to increase the contrast of the display image, the transparent surface material 10 may be provided with an antireflection layer on the surface opposite to the side on which the adhesive layer 14 is formed. Examples of the method of providing the antireflection layer include a method of directly forming an inorganic thin film on the surface of the transparent surface material 10, a method of bonding a transparent resin film provided with the antireflection layer to the transparent surface material 10, and the like.
Further, depending on the purpose, a part or the whole of the transparent face material 10 is colored, or a part or the whole of the surface of the transparent face material 10 is polished to form a glass to scatter light, or the surface of the transparent face material 10 is scattered. Further, a minute unevenness or the like may be formed on a part or the whole of the light to refract or reflect the transmitted light. Further, a colored film, a light scattering film, a photorefractive film, a light reflecting film, or the like may be attached to a part or the whole of the surface of the transparent surface material 10.

The shape of the transparent face material 10 is usually rectangular for the purpose of matching the outer shape of the display device. Depending on the outer shape of the display device, a protective plate that covers the entire display surface of the display panel and has a curved shape in the outer shape can be used.
What is necessary is just to set the magnitude | size of the transparent surface material 10 suitably according to the external shape of a display apparatus.
From the viewpoint of mechanical strength and transparency, the thickness of the transparent face material 10 is preferably 0.5 to 25 mm in the case of a glass plate. In applications such as television receivers and PC displays used indoors, 1 to 6 mm is preferable from the viewpoint of weight reduction of the display device, and 3 to 20 mm is preferable in public display applications installed outdoors. When chemically strengthened glass is used, the thickness of the glass is preferably about 0.5 to 1.5 mm in terms of strength. In the case of a transparent resin plate, the thickness of the transparent resin plate is preferably 2 to 10 mm.

<Shading printing part>
The light-shielding printing unit 12 hides wiring members and the like connected to the display panel so that areas other than the image display area of the display panel to be described later cannot be seen from the transparent surface material 10 side. The light-shielding printing unit 12 can be formed on the surface on which the adhesive layer 14 is formed or on the opposite surface. In terms of reducing the parallax between the light shielding printing unit 12 and the image display region, it is preferable to form the light shielding printing unit 12 on the surface on the side where the adhesive layer 14 is formed. When the transparent surface material 10 is a glass plate, it is preferable to use ceramic printing containing a black pigment for the light shielding printing portion 12 because of high light shielding properties.
When the display panel wiring member or the like has a structure that cannot be seen from the side of the display panel observation, or is concealed by another member such as a housing of the display device, or adheres to the bonded surface material other than the display panel When the layered transparent face material 1 is bonded, the light shielding printing portion 12 may not be formed on the transparent face material 10.

<Adhesive layer>
The pressure-sensitive adhesive layer 14 includes a layered portion 18 that extends along the surface of the transparent face material 10, and a weir-shaped portion 20 that touches and surrounds the periphery of the layered portion 18.
The layered portion 18 is a portion made of a cured product (transparent resin) formed by curing the first composition of the present invention.
The weir-shaped portion 20 is a portion made of a cured product (transparent resin) formed by applying and curing a second composition to be described later.

[Layered part]
The layered portion 18 is preferably a cured product of a photocurable resin composition containing a photopolymerization initiator (E1) because it can be cured at a low temperature and has a high curing rate.
The thickness of the layered portion 18 is preferably 0.03 to 2 mm, and more preferably 0.1 to 0.8 mm. If the thickness of the layered portion 18 is equal to or greater than the lower limit value, the layered portion 18 can effectively buffer an impact or the like caused by an external force from the transparent surface material 10 side, and the display panel or the like can be protected. Moreover, in the manufacturing method of the display apparatus of this invention, even if the foreign material which does not exceed the thickness of the layered part 18 mixes between the display panel and the transparent surface material 1 with the adhesion layer, the thickness of the layered part 18 is large. There is little effect on light transmission performance without change. If the thickness of the layered portion 18 is less than or equal to the upper limit value, voids are unlikely to remain in the layered portion 18, and the entire thickness of the display device does not increase more than necessary.

[Weir-shaped part]
The second composition forming the weir 20 may be a photocurable resin composition or a thermosetting resin composition. The weir-like portion 20 is preferably a cured product of a photocurable resin composition containing a curable compound and a photopolymerization initiator (E2) because it can be cured at a low temperature and has a high curing rate. In addition, if the second composition is a photocurable resin composition, a high temperature is not required for curing, so there is little risk of damage to the display panel due to high temperatures.
Moreover, the 2nd composition of the composition similar to the 1st composition used for formation of a layered part is apply | coated to the peripheral part of the surface of a face material, is semi-hardened, and is the process (X4) or process (Y4) mentioned later. It is good also as a dam-like part before hardening.

  Examples of the second composition include silicone resin (organopolysiloxane), urethane oligomer, urethane acrylate oligomer, and the like.

The viscosity at 25 ° C. of the second composition is preferably 500 to 3000 Pa · s, more preferably 800 to 2500 Pa · s, and still more preferably 1000 to 2000 Pa · s. If the viscosity of the second composition is 500 Pa · s or more, the shape of the weir-shaped portion before curing can be maintained for a relatively long time, and the height of the weir-shaped portion before curing can be sufficiently maintained. If the viscosity of the second composition is 3000 Pa · s, the weir-shaped portion before curing can be formed by coating.
Moreover, even when the viscosity at the time of application of the second composition forming the weir-like portion is smaller than 500 Pa · s, when the second composition is a photocurable resin composition, immediately after the application. What is necessary is just to make the viscosity of the 2nd composition after light irradiation be the above-mentioned preferable range by irradiating light. From the viewpoint of ease of application, the viscosity at the time of application of the second composition is preferably 500 Pa · s or less, and more preferably 200 Pa · s or less.
The viscosity of the second composition is measured using an E-type viscometer at 25 ° C.
Moreover, in order to maintain the space | interval of the transparent surface material 10 and a display panel, you may mix | blend the spacer particle | grains of a predetermined particle diameter with a 2nd composition.

As a 2nd composition, the composition containing an oligomer (G), a monomer (H), and a photoinitiator (E2) is preferable.
The oligomer (G) is an oligomer having a curable functional group and a number average molecular weight of 30,000 to 100,000.
The monomer (H) is a monomer having a curable functional group and a molecular weight of 125 to 600.

  Examples of the curable functional group possessed by the oligomer (G) and the monomer (H) include an acryloyloxy group and a methacryloyloxy group. The curable functional group of the oligomer (G) and the monomer (H) is preferably an acryloyloxy group or a methacryloyloxy group from the viewpoint that a curing rate is high and a highly transparent weir-like part is obtained. In addition, since the difference in reactivity of the curable functional group between the oligomer (G) and the monomer (H) is reduced and a homogeneous layered portion is obtained, the curable functional group possessed by the oligomer (G) is an acryloyloxy group, It is particularly preferable that the curable functional group of the monomer (H) is a methacryloyloxy group.

The number average molecular weight of the oligomer (G) is 30,000 to 100,000, preferably 40,000 to 80,000, and more preferably 50,000 to 65,000. If the number average molecular weight of an oligomer (G) is in the said range, it will be easy to adjust the viscosity of a 2nd composition to the said range.
The molecular weight of the monomer (H) is 125 to 600, preferably 140 to 400, and more preferably 150 to 350. When the molecular weight of the monomer (H) is 125 or more, volatilization of the monomer (H) when producing a laminate such as a display device is suppressed. When the molecular weight of the monomer (H) is 600 or less, the solubility of the monomer (H) in the high molecular weight oligomer (G) can be increased, and the viscosity adjustment as the second composition can be suitably performed.

The average number of curable functional groups of the oligomer (G) is preferably 1.8 to 4 from the viewpoint of the curability of the first composition and the mechanical properties of the layered portion.
Examples of the oligomer (G) include a urethane oligomer having a urethane bond, a poly (meth) acrylate of a polyoxyalkylene polyol, and a poly (meth) acrylate of a polyester polyol.
Urethane oligomers synthesized using polyols and polyisocyanates as raw materials are preferred from the viewpoint that the mechanical properties of the cured resin and adhesion to the face material can be widely adjusted by the molecular design of the urethane chain, and the oligomers described later (G1) is more preferable. The polyol is more preferably a polyoxyalkylene polyol.

(Oligomer (G1))
Since the oligomer (G1) having a number average molecular weight in the range of 30,000 to 100,000 has a high viscosity, it is difficult to synthesize by a normal method, and even if synthesized, it is difficult to mix with the monomer (H).
Therefore, after the oligomer (G1) is synthesized by a synthesis method using the monomer (H) (the following monomers (H1) and (H2)), the obtained product is used as the second composition as it is or obtained. It is preferable to further dilute the obtained product with the monomer (H) (the following monomer (H1), monomer (H3), etc.) and use it as the second fat composition.
Monomer (H1): Monomer (H) that has a curable functional group and does not have a group that reacts with an isocyanate group.
Monomer (H2): A monomer having a curable functional group and a group that reacts with an isocyanate group among the monomers (H).
Monomer (H3): Monomer (H) having a curable functional group and a hydroxyl group.

Synthesis method of oligomer (G1):
A method of reacting a polyol and a polyisocyanate in the presence of a monomer (H1) used as a diluent to obtain a prepolymer having an isocyanate group, and then reacting the monomer (H2) with the isocyanate group of the prepolymer.
Examples of the polyol and polyisocyanate include known compounds, for example, polyol (i) and diisocyanate (ii) described as raw materials for the urethane oligomer (a) described in International Publication No. 2009/016943. .

As specific examples of the polyol, those similar to the polyol exemplified in the first composition can be used. The kind of polyol may or may not be the same as that of the first composition, but is preferably the same. Moreover, if the polyoxyalkylene polyol which has an oxyalkylene group containing an oxypropylene group and an oxyethylene group is used, compatibility with the other component of a 2nd composition can be improved, and it is more preferable.
The polyol may be one kind or two or more kinds.

As polyisocyanate, the thing similar to the polyisocyanate illustrated by the 1st composition can be used. The polyisocyanate may or may not be the same as the first composition, but is preferably the same.
The polyisocyanate may be one type or two or more types.

  As the monomer (H1), an alkyl (meth) acrylate having an alkyl group having 8 to 22 carbon atoms (n-dodecyl (meth) acrylate, n-octadecyl (meth) acrylate, n-behenyl (meth) acrylate, etc.)), and the like. And (meth) acrylates having an alicyclic hydrocarbon group (isobornyl (meth) acrylate, adamantyl (meth) acrylate, etc.).

  Examples of the monomer (H2) include monomers having active hydrogen (hydroxyl group, amino group, etc.) and a curable group. Specific examples of the monomer (H2) include hydroxyalkyl (meth) acrylates having a C2-C6 hydroxyalkyl group (2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl). (Meth) acrylate, 4-hydroxybutyl (meth) acrylate, etc.). Especially, as a monomer (H2), the hydroxyalkyl acrylate which has a C2-C4 hydroxyalkyl group is preferable.

The monomer (H) may contain the monomer (H1) used as a diluent in the synthesis method of the oligomer (G1). Moreover, the unreacted monomer (H2) used for the synthesis method of the oligomer (G1) may be included as the monomer (H).
Moreover, it is preferable that a monomer (H) contains a monomer (H3) from the point of the adhesiveness of a face material and a weir-like part, and the solubility point of the various additives mentioned later.
Monomers (H3) include hydroxy methacrylates having a hydroxyalkyl group having 1 to 2 hydroxyl groups and 3 to 8 carbon atoms (2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl). Methacrylate) and the like are preferable, and 2-hydroxybutyl methacrylate is particularly preferable.

The proportion of the monomer (H) in the second composition is preferably 15 to 50% by mass and more preferably 20 to 45% by mass with respect to the total (100% by mass) of the oligomer (G) and the monomer (H). More preferably, it is 25-40 mass%. When the proportion of the monomer (H) is 15% by mass or more, the curability of the second composition and the adhesion between the face material and the weir-shaped portion are good. If the ratio of a monomer (H) is 50 mass% or less, it will be easy to adjust the viscosity of a 2nd composition to 500 Pa.s or more.
In addition, in the synthesis | combination of an oligomer (G1), since the monomer (H2) which reacted with the isocyanate group of the prepolymer exists as a part of the oligomer (G), it is included in the content of the monomer (H) in the second composition. I can't. On the other hand, in the synthesis of the oligomer (G1), the monomer (H1) used as a diluent and the monomer (H) added after synthesizing the oligomer (G1) are included in the ratio of the monomer (H) in the second composition. It is.

(Photopolymerization initiator (E2))
The photopolymerization initiator (E2) contained in the photocurable second composition includes acetophenone, ketal, benzoin or benzoin ether, phosphine oxide, benzophenone, thioxanthone, quinone, and the like. Initiators are mentioned. Among these, as the photopolymerization initiator (E2), acetophenone-based, ketal-based, and benzoin ether-based photopolymerization initiators are preferable. When curing with visible light having a short wavelength, a phosphine oxide-based photopolymerization initiator is more preferable from the viewpoint of the absorption wavelength region. By using two or more kinds of photopolymerization initiators (E2) having different absorption wavelength ranges, the curing time can be further accelerated and the surface curability in the weir-like portion can be increased.

  The content of the photopolymerization initiator (E2) in the photocurable second composition is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass in total of the oligomer (G) and the monomer (H). 0.1-5 mass parts is more preferable.

(Additive)
Examples of the additive added to the second composition include the same additives as those mentioned for the first composition. As an additive added to the second composition, a polymerization inhibitor and a light stabilizer are preferable. In particular, by including a polymerization inhibitor in an amount smaller than the polymerization initiator, the storage stability of the second composition can be improved, and the molecular weight of the weir-like portion after curing can also be adjusted.
The total amount of these additives is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less with respect to 100 parts by mass in total of the oligomer (G) and the monomer (H).

  Since the area outside the image display area of the normal display panel is relatively narrow, it is preferable that the width of the weir 20 is narrow. The width of the weir 20 is preferably 0.5 to 2 mm, and more preferably 0.8 to 1.6 mm.

  It is preferable that the shear elastic modulus at 35 ° C. of the weir 20 is larger than the shear elastic modulus at 35 ° C. of the layered portion 18. If the shear elastic modulus of the weir-like part 20 is larger than the shear elastic modulus of the layered part 18, the display panel is attached to the peripheral part of the adhesive layer 14 when the display panel and the transparent surface material 1 with the adhesive layer are bonded. Even if voids remain at the interface between the adhesive layer 14 and the adhesive layer 14, the voids are not easily opened to the outside, and are easily formed as independent voids. Therefore, after pasting the display panel and the transparent surface material 1 with the adhesive layer in a reduced pressure atmosphere, when the pressure is returned to the atmospheric pressure atmosphere, the pressure in the gap (still reduced pressure) and the adhesive layer 14 are applied. The volume of the void is reduced by the pressure difference from the pressure (atmospheric pressure), and the void is likely to disappear.

The difference between the thickness of the dam-like portion 20 and the thickness of the layer-like portion 18 is preferably 0.05 mm or less, and more preferably 0.03 mm or less, from the viewpoint of suppressing generation of a gap due to a step between the dam-like portion 20 and the layer-like portion 18. .
The difference between the thickness of the weir 20 and the thickness of the layer 18 is obtained by measuring the total thickness of the transparent surface 10 and the layer 18 or the weir 20 formed thereon using a laser displacement meter. Find from the difference. Further, the thickness of the layered portion 18 is the thickness of the peripheral portion of the layered portion 18 in contact with the weir-shaped portion 20.

  When the thickness of the dam-like portion 20 is thicker than the thickness of the layer-like portion 18 in at least a part of the region where the dam-like portion 20 and the layer-like portion 18 are close to each other, the thinnest of the layer-like portion 18 with respect to the thickness of the dam-like portion 20 The ratio of the thickness of the part is preferably ½ or more and 99/100 or less. When the ratio is within the above range, the gap 110 is not opened to the outside, and tends to be an independent gap 110.

[Protective film]
The protective film 16 is required not to be firmly adhered to the pressure-sensitive adhesive layer 14 and to be able to be attached to a support surface material in a manufacturing method described later. Therefore, the protective film 16 is preferably a self-adhesive protective film in which one side of a base film having relatively low adhesion, such as polyethylene, polypropylene, and fluorine resin, is an adhesive surface.
The adhesive strength of the adhesive surface of the protective film 16 is preferably 0.01 to 0.1 N, preferably 0.02 to 0.06 N in a 50 mm wide specimen in a 180 degree peel test at a peel rate of 300 mm / min with respect to the acrylic plate. Is more preferable. If the said adhesive force is more than a lower limit, sticking to a support surface material is possible. If the said adhesive force is below an upper limit, it is easy to peel the protective film 16 from a support surface material.

  The thickness of the protective film 16 varies depending on the resin to be used, but when a relatively flexible film such as polyethylene or polypropylene is used, 0.04 to 0.2 mm is preferable, and 0.06 to 0.1 mm is more preferable. . If the thickness of the protective film 16 is equal to or greater than the lower limit value, deformation of the protective film 16 can be suppressed when the protective film 16 is peeled from the adhesive layer 14. If the thickness of the protective film 16 is not more than the upper limit value, the protective film 16 is easily bent at the time of peeling, and the protective film 16 is easily peeled off from the adhesive layer 14.

  Further, by providing a back layer on the back surface opposite to the adhesive surface of the protective film 16, peeling from the adhesive layer 14 can be further facilitated. Also for the back layer, it is preferable to use a film with relatively low adhesion, such as polyethylene, polypropylene, and fluorine resin. In order to further facilitate the peeling of the protective film 16, a release agent such as silicone may be applied to the protective film 16 within a range that does not adversely affect the adhesive layer 14.

[Support surface material]
As the supporting face material, it is preferable to use a rigid face material having a smooth surface. For example, glass, a transparent resin plate, etc. are mentioned, and glass is particularly preferable because the substance itself does not absorb UV light. As the material of the glass, any of tempered glass and non-tempered glass can be used.

[Other forms]
In addition, the transparent surface material 1 with an adhesive layer in the illustrated example is an example in which the surface material is a protective plate of a display device, but the transparent surface material with an adhesive layer of the present invention is not limited to the illustrated example, What is necessary is just to have a specific adhesion layer formed on at least one surface of the face material.
In addition, the transparent face material with an adhesive layer of the present invention has a polarizing means (film-like absorption polarizer, wire grid polarizer, etc.), light between the face material (protective plate) and the specific adhesive layer. Modulating means (a retardation film such as a quarter-wave plate, a retardation film patterned in a stripe shape, or the like) may be provided.

≪Method for producing transparent surface material with adhesive layer≫
As a manufacturing method of the transparent surface material with the adhesion layer of this invention, the method which has the following process (X1)-(X5) is mentioned, for example.
(X1) A step of forming an uncured weir-like portion by applying the liquid second composition to the peripheral portion of the surface of the face material.
(X2) The process of supplying a liquid 1st composition to the area | region enclosed by the uncured weir-like part of the surface of the said face material.
(X3) Under a reduced-pressure atmosphere of 100 Pa or less, the support surface material on which the protective film is adhered is stacked on the first composition so that the protective film is in contact with the first composition, and a transparent surface material, The process of obtaining the precursor laminated body by which the uncured layered part which consists of a 1st composition was sealed with the protective film and the uncured weir-like part.
(X4) A step of curing the uncured layered portion and the uncured weir-shaped portion in a state where the precursor laminate is placed in a pressure atmosphere of 50 kPa or more to form an adhesive layer having the layered portion and the weir-shaped portion. .
(X5) The process of peeling a support surface material from a protective film.

  The method for producing a transparent surface material with an adhesive layer according to the present invention includes a first composition enclosed between a surface material in a reduced pressure atmosphere and a protective film adhered to the support surface material, and is high in an atmospheric pressure atmosphere or the like. This is a method for forming a layered portion by curing a first composition contained in a pressure atmosphere. The method of containing the first composition under reduced pressure is not a method of injecting the first composition into a narrow and wide space between the face material and the protective film attached to the support face material, The first composition is supplied to the entire surface, and then the protective film attached to the support surface material is stacked, and the first composition is contained between the face material and the protective film attached to the support surface material. Adopt the method.

  An example of a method for producing a transparent laminate by containing a curable resin composition under reduced pressure and by curing the curable resin composition under an atmospheric pressure atmosphere is known. For example, International Publication No. 2008/81838 and International Publication No. 2009/16943 describe a method for producing a transparent laminate and a curable resin composition used in the production method. In the production of the transparent face material with an adhesive layer of the present invention, the production methods described in these documents may be adopted except that the first composition of the present invention is used.

  In the transparent face material with an adhesive layer of the present invention, since the oligomer (C) is contained in the first composition, the fluidity of the layered part is high, and voids remain in the layered part sealed under reduced pressure during production. However, the gap disappears in a short time due to the differential pressure between the pressure in the gap and the pressure applied to the adhesive layer when returned to the atmospheric pressure atmosphere. Moreover, the transparent surface material with the adhesion layer of this invention becomes low-elasticity because the oligomer (C) is contained, the stress concerning the bonded display panel is small, and display unevenness can be suppressed. . The transparent face material with an adhesive layer as described above is suitable as a protective plate for a display device.

≪Laminated body≫
The laminate of the present invention has a pair of face materials and an adhesive layer having a layered portion and a weir-like portion provided so as to be in contact with two faces facing each other between the face materials, It consists of a cured product of the first composition of the present invention.
The laminate of the present invention is useful as laminated glass (windshield glass, safety glass, crime prevention glass, etc.), for displays, for solar cells and the like.
The laminate of the present invention is particularly useful as a display device having a display panel that is one surface material and a transparent surface material that is the other surface material.

<Effect>
In the laminate of the present invention, the same effect as that of the non-curable oligomer is obtained by using the first composition containing the oligomer (C) having an average number of curable functional groups of 0.5 to 1. Even when a predetermined time has elapsed after the formation of the adhesive layer, it is possible to sufficiently suppress the generation or remaining of voids at the interface between the adhesive layer and the surface material to be bonded.

≪Laminated body manufacturing method≫
As a manufacturing method of the laminated body of this invention, the method (x) which uses the transparent surface material with an adhesion layer mentioned later and the method (y) which does not use the transparent surface material with an adhesion layer are mentioned.
In the method (x), under a reduced-pressure atmosphere of 1 kPa or less, the transparent surface material with the adhesive layer and the other surface material without the adhesive layer (bonded surface material), the adhesive layer is the other surface material. It is the method of laminating and sticking so that it may touch.

The method (y) is a method having the following steps (Y1) to (Y4).
(Y1) A step of forming an uncured weir-like portion by applying a liquid second composition for forming a weir-like portion to the peripheral portion of the surface of one face material.
(Y2) The process of supplying a liquid 1st composition to the area | region enclosed by the uncured weir-like part of the surface of said one face material.
(Y3) In a reduced pressure atmosphere of 1 kPa or less, the other face material is stacked on the first composition, and one face material, the other face material, and the uncured weir-like portion are not formed of the first composition. The process of obtaining the precursor laminated body by which the layered part of hardening was sealed.
(Y4) A step of curing the uncured layered portion and the uncured weir-shaped portion in a state where the precursor laminate is placed in a pressure atmosphere of 50 kPa or more to form an adhesive layer having the layered portion and the weir-shaped portion. .

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by the following description.
[Face material]
Frame by ceramic printing with black pigment so that the translucent part is an area of 68 mm length and 68 mm width on the peripheral part of one surface of soda lime glass of length 100 mm, width 100 mm and thickness 1.3 mm A light-shielding printing part was formed in a shape to prepare a face material-i.

[Support surface material]
On one side of a transparent plate made of soda lime glass having a length of 100 mm, a width of 100 mm, and a thickness of 3 mm, a protective film having a length of 130 mm, a width of 130 mm, and a thickness of 0.75 mm (manufactured by Tosero, Puretect VLH-9), The support surface material-ii to which the protective film was stuck was prepared by sticking with a rubber roll so that the adhesive surface of the protective film was in contact with the glass.

[Laminated surface material]
As the surface material to be bonded, a polarizing plate with an adhesive layer (Polatechno Co., Ltd., KN-18240T) is attached to one surface of soda lime glass having a length of 100 mm, a width of 100 mm, and a thickness of 1.7 mm, and a liquid crystal The to-be-bonded surface material-iii which substitutes a display panel was used.

[Oligomer (A)]
Oligomer (A-1): a bifunctional polypropylene polyol having a molecular end modified with ethylene oxide (number average molecular weight calculated from hydroxyl value (28 mgKOH / g): 4000) and 3-isocyanatomethyl-3,5,5- Trimethylcyclohexyl diisocyanate was mixed at a molar ratio of 4: 5 and reacted at 70 ° C. in the presence of a tin catalyst to obtain an isocyanate-terminated prepolymer. To the obtained isocyanate-terminated prepolymer, 2-hydroxyethyl acrylate was added so as to have the same equivalent as the isocyanate group of the prepolymer and reacted at 70 ° C. to obtain an oligomer (A-1) (urethane acrylate oligomer). The number of curable functional groups of the oligomer (A-1) was 2, the number average molecular weight was about 24,000, and the viscosity at 25 ° C. was about 830 Pa · s.

[Oligomer (C)]
Oligomer (C-1): A monofunctional polypropylene polyol (number average molecular weight calculated from hydroxyl value (16.8 mgKOH / g): 3340) and isophorone diisocyanate (IPDI) were mixed at a molar ratio of 1: 0.975. An isocyanate-terminated prepolymer was obtained by reacting at 70 ° C. in the presence of a tin catalyst. To the obtained isocyanate-terminated prepolymer, 2-hydroxyethyl acrylate was added so as to have the same equivalent as the isocyanate group of the prepolymer and reacted at 70 ° C. to obtain an oligomer (C-1).
The average number of curable functional groups of the oligomer (C-1) was 0.95, the number average molecular weight was about 3,500, and the viscosity at 25 ° C. was about 880 mPa · s.
Oligomer (C-2): A monofunctional polypropylene polyol (number average molecular weight calculated from hydroxyl value (11.0 mgKOH / g): 5100) and 2-methacryloyloxyethyl isocyanate are mixed at a molar ratio of 1: 0.95. The oligomer (C-2) was obtained by reacting at 70 ° C. in the presence of a tin catalyst.
The average number of curable functional groups of the oligomer (C-2) was 0.95, the number average molecular weight was about 5,100, and the viscosity at 25 ° C. was about 1700 mPa · s.

[Non-curable oligomer (D)]
Non-curable oligomer (D-1): The same bifunctional polypropylene polyol as that used in the synthesis of the oligomer (A-1), whose molecular ends were modified with ethylene oxide (calculated from the hydroxyl value (28 mgKOH / g)) Number average molecular weight: 4000) was used.

[Resin composition for layered portion formation]
40 parts by mass of oligomer (A-1), 30 parts by mass of 2-hydroxybutyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., light ester HOB) as monomer (B1), and 30 parts by mass of n-dodecyl methacrylate as monomer (B2) Were mixed uniformly. Thereafter, to 100 parts by mass of the mixture, 0.3 part by mass of a trade name “IRGACURE 819” (photopolymerization initiator, manufactured by Ciba Specialty Chemicals) and 2,5-di-tert-butylhydroquinone ( 0.04 parts by mass of a polymerization inhibitor (manufactured by Tokyo Chemical Industry Co., Ltd.), 0.3 parts by mass of a trade name “TINUVIN 109” (manufactured by Ciba Specialty Chemicals, Inc., UV absorber), and n-dodecyl mercaptan (chain transfer) The base composition (P-1) was obtained by uniformly dissolving 0.3 part by mass of the agent, manufactured by Kao Corporation, Thiocalcol 20).

70 parts by mass of the base composition (P-1) and 30 parts by mass of the non-curable oligomer (D-1) are uniformly dissolved and placed in a vacuum apparatus in an open state while being put in a container, The inside of the decompression device was depressurized to about 20 Pa and held for 10 minutes to perform defoaming treatment to obtain Composition-1.
Further, 70 parts by mass of the base composition (P-1) and 30 parts by mass of the kneaded material having a mass ratio of 1: 1 of the oligomer (C-1) and the oligomer (C-2) are uniformly dissolved, The defoaming process was performed by installing in a decompression device in an open state while being put in a container, reducing the pressure in the decompression device to about 20 Pa, and maintaining it for 10 minutes to obtain Composition-2.
Composition-1 and Composition-2 are mixed uniformly at a mixing ratio (unit: mass%) shown in Table 1 to form the first composition-1 to the first composition-4 for forming a layered portion. Obtained.

[Resin composition for weir-like portion formation]
A bifunctional polypropylene polyol having a molecular terminal modified with ethylene oxide (number average molecular weight calculated from hydroxyl value (28 mgKOH / g): 4000) and hexamethylene diisocyanate were mixed at a molar ratio of 6: 7, and isobornyl acrylate ( Osaka Organic Chemical Industry Co., Ltd., IBXA) was added so that it might become 30 mass%, and it was made to react at 70 degreeC in presence of a tin catalyst, and the isocyanate terminal prepolymer was obtained. To the obtained isocyanate-terminated prepolymer, 2-hydroxyethyl acrylate was added so as to have the same equivalent as the isocyanate group of the prepolymer, reacted at 70 ° C., and 30% by mass of isobornyl acrylate (monomer (H)). A diluted urethane acrylate oligomer (hereinafter referred to as “oligomer (G1-1)”) was obtained. The average number of curable functional groups of the oligomer (G1-1) was 2, the number average molecular weight was 55,000, and the viscosity at 60 ° C. was 580 Pa · s.
90 parts by mass of the oligomer (G1-1) and 10 parts by mass of 2-hydroxybutyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., light ester HOB) were uniformly mixed to obtain a mixture. 100 parts by weight of the mixture, 0.9 part by weight of 1-hydroxy-cyclohexyl-phenyl-ketone (photopolymerization initiator, manufactured by Ciba Specialty Chemicals, IRGACURE 184), bis (2,4,6-trimethylbenzoyl) ) -Phenylphosphine oxide (photopolymerization initiator, manufactured by Ciba Specialty Chemicals, IRGACURE 819), 0.1 part by mass, 2,5-di-tert-butylhydroquinone (polymerization inhibitor, manufactured by Tokyo Chemical Industry Co., Ltd.) 0.04 parts by mass of UV and 0.3 part by mass of UV absorber (manufactured by Ciba Specialty Chemicals, TINUVIN 109) were uniformly mixed. The mixture is placed in a decompression device in an open state while being put in a container, and the inside of the decompression device is depressurized to about 20 Pa and held for 10 minutes to perform a defoaming process to form a weir-shaped portion. A second composition-1 was obtained.

[Example 1]
(Process (X1))
The second composition-1 is applied with a dispenser so that the width is about 1 mm and the coating thickness is about 0.6 mm over the entire circumference at a position of about 7 mm from the inner edge of the shading printed portion of the face material-i. Part was formed.
Next, a weir-shaped portion formed on the face material-i for 30 seconds with ultraviolet rays and 450 nm or less visible light from a chemical lamp (manufactured by NEC, FL15BL, peak wavelength: 365 nm, irradiation intensity: ² mW / cm ² ) Were uniformly irradiated. This thickened the weir.
(Process (X2))
The first composition-1 was supplied to a plurality of locations in a region inside the weir-like portion formed on the face material-i using a dispenser so that the total mass was 2.5 g.
While supplying the first composition-1, there was no breakage such as breakage, and the shape of the weir-like portion was maintained.

(Process (X3))
The face material-i was placed flat on a lower surface plate in a decompression device in which a pair of surface plate elevating devices were installed so that the surface of the first composition-1 was on the upper surface.
Using an electrostatic chuck, the support surface material-ii to which the protective film was adhered was held on the lower surface of the upper surface plate of the lifting device in the decompression device. The vertical position of the protective film was such that the distance from the face material-i was 10 mm.
The decompression device was sealed and evacuated until the pressure in the decompression device reached about 40 Pa. The upper and lower surface plates are brought close to each other by an elevating device in the decompression device, and the face material -i and the support surface material -ii to which the protective film is adhered are passed through the first composition-1 at a pressure of 2 kPa. Crimped and held for 10 seconds. Static electricity is removed from the electrostatic chuck, the supporting surface material -ii is separated from the upper surface plate, the pressure reducing device is returned to the atmospheric pressure atmosphere in about 15 seconds, and the first composition is composed of the surface material -i, the protective film and the weir-shaped portion. Precursor laminate-1 in which the layered portion consisting of -1 was sealed was obtained.
In Precursor Laminate-1, the shape of the weir-like portion was maintained in an almost initial state.

(Process (X4))
Ultraviolet rays from a chemical lamp (NEC, FL15BL, peak wavelength: 365 nm, irradiation intensity: ² mW / cm ² ) and the weir-like portion and the layer-like portion of the precursor laminate-1 from the support surface material-ii side A pressure-sensitive adhesive layer was formed by uniformly irradiating visible light of 450 nm or less for 10 minutes to cure the weir-like portion and the layer-like portion.
The irradiation intensity was measured using an illuminometer (manufactured by Ushio Electric Co., Ltd., UV intensity meter Unimeter UIT-101). The thickness of the layered portion after curing was approximately uniform at 0.4 mm.

(Process (X5))
By peeling off the support surface material-ii in the precursor laminate-1 from the protective film, a transparent surface material-1 with an adhesive layer to which the protective film was attached was obtained.

[Examples 2 to 4]
Except having changed the kind of 1st composition as shown in Table 2, it carried out similarly to Example 1, and obtained the transparent surface material-2 with the adhesion layer-the transparent surface material-4 with the adhesion layer.

[Adhesion layer deformation evaluation]
(1) Long-term storage acceleration test The protective film was peeled off from the transparent surface material with an adhesive layer obtained in each example and stored in a thermostat at 80 ° C for 5 days.
(2) Deformation evaluation of adhesive layer For the evaluation of the shape of the adhesive layer, a digital microscope VHX-1000 manufactured by Keyence Corporation was used, and the shape was measured using the depth of focus. The measurement location was a part extending over a distance of about 5 mm on the adhesive layer surface extending from the outer peripheral end of the weir-like part at the center part of one side of the transparent face material with the adhesive layer to the layered part. In the measurement, a silver paste was thinly applied to the surface of the adhesive layer for the purpose of improving measurement sensitivity. The measurement was performed before and after the acceleration test of (1). As the shape change, the displacement amount of the weir-like part and the layer-like part before and after the acceleration test was evaluated.
In the deformation evaluation, the difference in height between the highest point of the dam-like resin and the lowest point of the stratified resin over a width of 2 mm centered on the boundary between the dam-like resin and the layer-like resin in the measurement location is defined as a step (deformation amount). ).

[Evaluation of gaps in the bonding process with the surface material to be bonded]
After the acceleration test of (1) in the step evaluation, the transparent surface material with the adhesive layer from which the protective film was peeled was subjected to vacuum degassing treatment. Then, the transparent surface material with the adhesive layer was placed flat on the lower surface plate in the decompression device in which the lifting device for the pair of surface plates was installed within 1 minute so that the surface of the adhesive layer was on the upper side. The conditions for the vacuum degassing treatment were an atmospheric pressure of 100 Pa and a treatment time of 10 minutes.
Using the electrostatic chuck, the bonded surface material -iii is held on the lower surface of the upper surface plate of the lifting device in the decompression device, and the distance between the bonded surface material -iii and the transparent surface material with the adhesive layer is 10 mm. It was.
The decompression device was sealed and evacuated until the pressure in the decompression device reached about 30 Pa. The upper and lower surface plates were brought close to each other by an elevating device in the decompression device, and the bonded surface material-iii and the transparent surface material with the adhesive layer were pressure-bonded with a pressure of 2 kPa through the adhesive layer and held for 10 seconds. The electrostatic chuck was neutralized, the surface material to be bonded -iii was separated from the upper surface plate, and the pressure reduction apparatus was returned to atmospheric pressure in about 20 seconds to obtain a laminate.
When the obtained laminate was observed immediately after lamination with the transparent surface material with the adhesive layer, there were many fine voids (bubbles) at the interface between the surface material to be bonded -iii and the adhesive layer of the transparent surface material with the adhesive layer. It was seen. The laminate was allowed to stand and evaluated for the disappearance of voids.

[Evaluation of resin viscoelasticity (measurement of storage shear modulus)]
Using a rheometer (Anton Paar, Physica MCR301), the first composition is placed between the soda lime glass stage and the measuring spindle (Anton Paar, D-PP20 / AL / S07). It was pinched in a 4 mm gap. A black light (FL15BL, manufactured by NEC Corporation) placed at 35 ° C. in a nitrogen atmosphere under a nitrogen atmosphere was irradiated with ² mW / cm ² of light for 10 minutes to 1% dynamic shear strain. Applied, the storage shear modulus of the layered portion of the adhesive layer was measured.
The evaluation results in Examples 1 to 4 are shown in Table 2. Example 1 is a comparative example, and Examples 2 to 4 are examples. Moreover, (C) / ((C) + (D)) in Table 2 means the ratio (mass%) of the oligomer (C) with respect to the sum total of the oligomer (C) and the non-curable oligomer (D).

  As shown in Table 2, as the ratio of (C) / ((C) + (D)) in the first composition for forming the layered portion increases, deformation that occurs on the adhesive layer surface after the acceleration test It was shown that the amount (step) is getting smaller. In the laminate using the transparent surface material with an adhesive layer-1 having a layered portion that does not contain the oligomer (C), the storage shear elastic modulus is preferable, but voids remain immediately after being bonded to the surface material to be bonded, and thereafter Voids remained until 24 hours later. On the other hand, in the laminate using the adhesive layer-attached transparent face material -2 to 4 having a layered portion containing the oligomer (C), it can be confirmed that voids disappear immediately after lamination or disappear with time. It was.

DESCRIPTION OF SYMBOLS 1 Transparent surface material with the adhesion layer 10 Transparent surface material 14 Adhesion layer 16 Protective film 18 Layered part 20 Weir-shaped part

Claims (9)

Curability for forming a layered portion in the pressure-sensitive adhesive layer, which is a pressure-sensitive adhesive layer for bonding a pair of face materials and has a layered portion extending along the surface of the face material and a weir-like portion surrounding the periphery of the layered portion A curable resin composition comprising the following oligomer (A), the following monomer (B) and the following oligomer (C), which is a resin composition.
Oligomer (A): An oligomer having a number average molecular weight of 1,000 to 100,000 and an average number of curable functional groups of 1.8 to 4.
Monomer (B): A monomer comprising at least one monomer having a molecular weight of 125 to 600 and a number of curable functional groups of 1 to 3, and including at least one monomer (B1) having a hydroxyl group.
Oligomer (C): An oligomer having a number average molecular weight of 1,000 to 20,000 and an average number of curable functional groups of 0.5 to 1.   Furthermore, the curable resin composition of Claim 1 containing a photoinitiator (E1). Furthermore, the curable resin composition of Claim 1 or 2 containing the following non-curable oligomer (D).
Non-curable oligomer (D): an oligomer which does not undergo a curing reaction with the oligomer (A), monomer (B) and oligomer (C) at the time of curing, has a hydroxyl group, and has a molecular weight per hydroxyl group of 400 to 8,000. .   The curable resin composition of Claim 3 whose ratio of the said oligomer (C) with respect to the sum total (100 mass%) of the said oligomer (C) and the said non-curable oligomer (D) is 50-100 mass%.   The curable resin composition according to any one of claims 1 to 4, wherein the curable functional group is an acryloyloxy group or a methacryloyloxy group. The oligomer (A) is a urethane acrylate oligomer obtained by reacting a polyol and a polyisocyanate to obtain a prepolymer having an isocyanate group at the terminal, and then reacting the following monomer (a1) with the isocyanate group of the prepolymer. And the oligomer (C) reacts with monool and polyisocyanate to obtain a prepolymer having an isocyanate group only at one end, and then reacts the following monomer (c1) with the isocyanate group of the prepolymer. The curable resin composition according to any one of claims 1 to 5, wherein the curable resin composition is an oligomer obtained by allowing the curable resin composition to be obtained.
Monomer (a1): A monomer having a molecular weight of 125 to 600, one or more acryloyloxy groups, and one group that reacts with an isocyanate group.
Monomer (c1): A monomer having a molecular weight of 125 to 600, having one or more acryloyloxy groups and one group that reacts with an isocyanate group.   The oligomer (A) is 6 to 80% by mass, the monomer (B) is 3 to 70% by mass with respect to the total (100% by mass) of the oligomer (A), monomer (B) and oligomer (C), The curable resin composition according to any one of claims 1 to 6, wherein the oligomer (C) is 10 to 70% by mass. A transparent face material, and an adhesive layer provided on the surface of the transparent face material,
The adhesive layer has a layered portion extending along the surface of the transparent face material, and a weir-shaped portion surrounding the periphery of the layered portion;
The transparent surface material with the adhesion layer which the said layered part becomes from the hardened | cured material of the curable resin composition of Claim 1. A pair of face materials, and an adhesive layer provided so as to contact two faces facing each other between the face materials,
The adhesive layer has a layered portion that extends along the surface of the face material, and a weir-shaped portion that surrounds the periphery of the layered portion,
The laminated body which the said layered part becomes from the hardened | cured material of the curable resin composition of Claim 1.

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