JP2017066211A - Manufacturing method of adhesive sheet and adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of an adhesive sheet good in adhesive property, having suppressed reduction of adhesive force with time and capable of suppressing phenomenon that an adherend becomes cloudy during relaminating, and the adhesive sheet.SOLUTION: There is provided a method for manufacturing an adhesive sheet having a resin layer by laminating a layer (Xβ), a layer (Y1) and a layer (Xα) in this order on a substrate or a release material, wherein at least a surface (α) of the layer (Xα) has adhesiveness, the layer (Xβ) is formed by using a composition (xβ) containing a resin, the layer (Y1) is formed by using a composition (y) containing a resin of 100 pts.mass and a tackifier of 1 pt.mass and the layer (Xα) is formed by using a resin (xα) containing an adhesive resin of 100 pts.mass and a tackifier of 1 pt.mass or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a method for producing an adhesive sheet and an adhesive sheet.

A general pressure-sensitive adhesive sheet is composed of a base material, a pressure-sensitive adhesive layer formed on the base material, and a release material provided on the pressure-sensitive adhesive layer as necessary. In the case where a material is provided, the release material is peeled off, and the pressure-sensitive adhesive layer is abutted against the adherend and attached. When high adhesive strength is required, a tackifier is generally used for these pressure-sensitive adhesive sheets. However, while high adhesive strength can be obtained, the tackifier is transferred to the adherend when reattaching. There is a problem that a phenomenon of clouding occurs due to contamination and contamination of the adherend surface.
By the way, for example, a pressure-sensitive adhesive sheet having a large application area used for identification / decoration, coating masking, surface protection of a metal plate, etc., is applied to an adherend with an adhesive layer and an adherend. There is a problem that air pockets are easily generated between them, and the portion becomes “bulging”, making it difficult to adhere the adhesive sheet to the adherend.

In order to solve such a problem, for example, in Patent Document 1, a release material having a fine emboss pattern is brought into contact with the surface of the pressure-sensitive adhesive layer, and a groove having a specific shape is formed on the surface of the pressure-sensitive adhesive layer. A pressure-sensitive adhesive sheet that is artificially arranged in a predetermined pattern is disclosed.
By using such an adhesive sheet, it is said that “air pockets” generated when sticking to an adherend can be released to the outside through a groove artificially formed on the surface of the adhesive layer. ing.

Special table 2001-507732 gazette

However, a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer in which grooves having a specific specific shape as described in Patent Document 1 are arranged in a predetermined pattern is difficult to remove air when the width of the groove is narrow. If it is wide, the surface base material is recessed and not only the appearance is inferior, but also the adhesive strength is reduced.
In addition, since the adhesive sheet has the grooves arranged in a predetermined pattern, the adhesive strength of the place where the grooves are arranged is locally inferior, and when the adhesive sheet is attached to the adherend, the adhesive sheet does not peel off from the place. May occur.
On the other hand, when the pressure-sensitive adhesive sheet is peeled off after being adhered to the adherend, the pressure-sensitive adhesive properties of the pressure-sensitive adhesive sheet are locally different. Therefore, depending on the direction in which the pressure-sensitive adhesive sheet is peeled off, there is a possibility that adhesive residue may be generated on the adherend. For example, in the case of a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer in which grooves are arranged in a lattice shape, adhesive residue may occur on the adherend when peeled in an oblique direction.
Further, when the punching process is performed on the pressure-sensitive adhesive sheet, the groove arrangement pattern and the punching pattern may overlap. In that case, there is a problem that the cutting depth varies, and the cutting cannot be appropriately formed in the adhesive sheet.

Moreover, generally, in order to make it easy to peel off the release material provided on the pressure-sensitive adhesive sheet, there is a case where a process (so-called back cracking process) is performed in which only the release material is cut and a trigger for peeling is provided. When performing the said process, after peeling off a peeling material from an adhesive sheet once and giving a cut | incision in a peeling material, it is common to laminate the peeling material and the adhesive layer of an adhesive sheet again.
However, since the embossed liner is used as the release material in the pressure-sensitive adhesive sheet described in Patent Document 1, it is difficult to follow the emboss pattern of the release material when laminating the release material and the adhesive layer again. It is necessary to prepare another release material that has not been subjected to.

Furthermore, in Patent Document 1, in order to form a fine structure in the pressure-sensitive adhesive layer, a method of laminating the pressure-sensitive adhesive layer and the base material after the pressure-sensitive adhesive is once applied to the emboss liner to form the pressure-sensitive adhesive layer ( The so-called transfer coating method is employed. However, when a base material having a low polarity surface such as a polyolefin base material is used as the base material, sufficient adhesion cannot be obtained at the interface between the base material and the pressure-sensitive adhesive layer.
In addition, unlike a release material made of paper, a release material made of a resin film makes it difficult to form a fine emboss pattern on the adhesive layer.
Moreover, in such an adhesive sheet as described above, when a large amount of tackifier is added in order to obtain high adhesive strength, it is difficult to solve the problem that the tackifier is transferred to the adherend and contaminated.

  The present invention provides a method for producing a pressure-sensitive adhesive sheet that has good pressure-sensitive adhesive properties when affixed to an adherend, suppresses a decrease in adhesive strength over time, and can suppress the phenomenon that the adherend is clouded when reattached. It aims at providing an adhesive sheet.

  The inventors have a resin layer formed by laminating a specific layer (Xβ), a layer (Y1), and a layer (Xα) on a base material or a release material, and the surface (α ) Was found to be able to solve the above problems, and the present invention was completed.

That is, the present invention provides the following [1] to [25].
[1] A resin layer formed by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a substrate or a release material, and at least the surface (α) of the layer (Xα) Is a method for producing a pressure-sensitive adhesive sheet,
The layer (Xβ) is formed using a composition (xβ) containing a resin,
The layer (Y1) is formed using a composition (y) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier,
A layer (X (alpha)) is a manufacturing method of the adhesive sheet formed using the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.
[2] The method for producing a pressure-sensitive adhesive sheet according to the above [1], comprising at least the following steps (1a) and (2a).
Step (1a): A coating film (xβ ′) composed of the composition (xβ), a coating film (y ′) composed of the composition (y), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating and forming a film (xα ′) in this order Step (2a): The coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1a) are simultaneously formed. Step [3] of drying to form layer (Xβ), layer (Y1), and layer (Xα) The method for producing a pressure-sensitive adhesive sheet according to the above [1], comprising at least the following steps (1b) and (2b) .
Step (1b): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y ′) comprising the composition (y), and the composition (xα Step (2b): The coating film (y ′) and the coating film (xα ′) formed in the step (1b) are simultaneously dried to form a layer. Step [4] for forming (Y1) and layer (Xα) A resin layer is formed by laminating layer (Xβ), layer (Y1), and layer (Xα) in this order on the substrate or release material. And at least the surface (α) of the layer (Xα) is a method for producing an adhesive sheet having adhesiveness,
The layer (Xβ) is formed using a composition (xβ) containing a resin,
The layer (Y1) is formed using a composition (y1) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier, and containing 15% by mass or more of fine particles,
A layer (X (alpha)) is a manufacturing method of the adhesive sheet formed using the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.
[5] The method for producing a pressure-sensitive adhesive sheet according to the above [4], comprising at least the following steps (1A) and (2A).
Step (1A): A coating film (xβ ′) composed of the composition (xβ), a coating film (y1 ′) composed of the composition (y1), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating film (xα ′) in this order Step (2A): Simultaneously forming the coating film (xβ ′), coating film (y1 ′), and coating film (xα ′) formed in step (1A) Step [6] of drying and forming layer (Xβ), layer (Y1), and layer (Xα) At least the following steps (1B) and (2B) The method for producing a pressure-sensitive adhesive sheet according to the above [4] .
Step (1B): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y1 ′) composed of the composition (y1), and the composition (xα Step (2B): The coating film (y1 ′) and the coating film (xα ′) formed in the step (1B) are simultaneously dried to form a layer. Step [7] of forming (Y1) and layer (Xα) [5] above, wherein an irregular recess is formed on the surface (α) of layer (Xα) by step (2A) or (2B). Or the manufacturing method of the adhesive sheet as described in [6].
[8] The above [1] to [1], wherein the content of the tackifier contained in the composition (xα) is 400 parts by mass or less with respect to 100 parts by mass of the adhesive resin in the composition (xα). 7] The manufacturing method of the adhesive sheet in any one of.
[9] The content of the tackifier contained in the composition (y) or the composition (y1) is 400 parts by mass with respect to 100 parts by mass of the resin in the composition (y) or the composition (y1). The manufacturing method of the adhesive sheet in any one of said [1]-[8] which is the following.
[10] The method for producing a pressure-sensitive adhesive sheet according to any one of the above [1] to [9], wherein the composition (xβ) does not substantially contain a tackifier.
[11] Content ratio [(xα) / (y)] of the tackifier contained in the composition (xα) and the tackifier contained in the composition (y) or the composition (y1) or [( The manufacturing method of the adhesive sheet according to any one of claims 1 to 10, wherein xα) / (y1)] is a mass ratio of 100/500 to 100/10.
[12] The method for producing a pressure-sensitive adhesive sheet according to any one of [1] to [10], wherein the coating amount (xα ′) is 1.5 to 800 g / m ² .
[13] The method for producing a pressure-sensitive adhesive sheet according to any one of the above [1] to [12], wherein the coating amount of the coating film (y ′) or the coating film (y1 ′) is 1.5 to 800 g / m ^2. .
[14] Ratio of coating amount [(xα ′) / (y ′)] or [(xα ′) / (y1) between the coating film (xα ′) and the coating film (y ′) or the coating film (y1 ′) ')] Is 100/5 to 100/2000, The manufacturing method of the adhesive sheet in any one of said [1]-[13].
[15] The method for producing a pressure-sensitive adhesive sheet according to any one of the above [1] to [14], wherein the content of the tackifier is 2 to 60% by mass relative to 100% by mass of the total mass of the resin layer.
[16] The adhesive sheet according to any one of [1] to [15], wherein the resin contained in the composition (xβ) and the composition (y) or the composition (y1) is an adhesive resin. Production method.
[17] The method for producing a pressure-sensitive adhesive sheet according to any one of the above [1] to [16], wherein the pressure-sensitive adhesive contained in the composition (xα) is an acrylic resin having a functional group.
[18] The method for producing a pressure-sensitive adhesive sheet according to the above [17], wherein the composition (xα) further contains one or more selected from a metal chelate crosslinking agent, an epoxy crosslinking agent, and an aziridine crosslinking agent.
[19] The method for producing a pressure-sensitive adhesive sheet according to the above [17] or [18], wherein the functional group is a carboxy group.
[20] The pressure-sensitive adhesive sheet according to any one of [4] to [19], wherein the fine particles contained in the composition (y) are one or more selected from silica particles, metal oxide particles, and smectites. Production method.
[21] A resin layer formed by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a substrate or a release material, and at least the surface (α) of the layer (Xα) Is an adhesive sheet having adhesiveness,
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed from a composition (y) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier,
The adhesive sheet whose layer (X (alpha)) is a layer formed from the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.
[22] A resin layer formed by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a substrate or a release material, and at least the surface (α) of the layer (Xα) Is an adhesive sheet having adhesiveness,
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed of a composition (y1) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier and containing 15% by mass or more of fine particles,
The adhesive sheet whose layer (X (alpha)) is a layer formed from the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.
[23] The pressure-sensitive adhesive sheet according to the above [22], which has an irregular recess on the surface (α) of the layer (Xα).
[24] The pressure-sensitive adhesive sheet according to [23], wherein the recess is formed by self-forming of the resin layer.
[25] The pressure-sensitive adhesive sheet according to any one of the above [21] to [24], wherein the composition (xβ) does not substantially contain a tackifier.

  According to the present invention, the pressure-sensitive adhesive sheet has good adhesive properties when affixed to an adherend, suppresses a decrease in adhesive strength over time, and can suppress the phenomenon that the adherend is clouded when reapplied. A manufacturing method and an adhesive sheet can be provided.

It is a cross-sectional schematic diagram of this adhesive sheet which shows an example of a structure of the adhesive sheet of this invention. It is a plane schematic diagram of the surface (α) when observed from the surface (α) side of the resin layer of the pressure-sensitive adhesive sheet of the present invention. It is a cross-sectional schematic diagram of this resin layer which shows an example of the shape at the surface ((alpha)) side of the resin layer which the adhesive sheet of this invention has. It is a figure for demonstrating the method of selection of the cross section prescribed | regulated by requirement (II), Comprising: It is a perspective view of the adhesive sheet of 1 aspect of this invention. It is an example of the schematic diagram of the cross section (P1) prescribed | regulated by requirements (II) with respect to the adhesive sheet of 1 aspect of this invention. A region (D) surrounded by a rectangular of 8 mm long × 10 mm wide arbitrarily selected on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Example 4 was used to obtain the surface (α This is a binarized image of an image taken from the side. A region (D) surrounded by a rectangle of 8 mm long × 10 mm wide arbitrarily selected on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Comparative Example 2 was used to obtain the surface of the resin layer (α This is a binarized image of an image photographed from the side.

In the present invention, for example, the description of “YY including XX component as main component” or “YY mainly composed of XX component” means that the component with the highest content among the components included in YY is the XX component. It means that there is. As content of the specific XX component in the said description, it is 50 mass% or more normally with respect to the whole quantity (100 mass%) of YY, Preferably it is 65-100 mass%, More preferably, it is 75-100 mass%, Furthermore, Preferably it is 85-100 mass%.
In the present invention, for example, “(meth) acrylic acid” indicates both “acrylic acid” and “methacrylic acid”, and the same applies to other similar terms.
Furthermore, the lower limit value and the upper limit value described in a stepwise manner can be independently combined for a preferable numerical range (for example, a range such as content). For example, from the description “preferably 10 to 90, more preferably 30 to 60”, “preferable lower limit (10)” and “more preferable upper limit (60)” are combined to make “10 to 60”. You can also.

[Method for producing pressure-sensitive adhesive sheet of the present invention]
The pressure-sensitive adhesive sheet production method of the present invention (hereinafter also referred to as “the production method of the present invention”) comprises a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a substrate or a release material. A pressure-sensitive adhesive sheet having a laminated resin layer and at least the surface (α) of the layer (Xα) (hereinafter, also simply referred to as “surface (α)”) having adhesiveness (hereinafter “the pressure-sensitive adhesive sheet of the present invention”) It is also a manufacturing method.
The manufacturing method of the present invention includes the following first manufacturing method and second manufacturing method.

<First manufacturing method>
In the 1st manufacturing method of this invention, a layer (X (beta)) is formed using the composition (x (beta)) containing resin, a layer (Y1) is 100 mass parts of resin, 1 mass part or more of tackifiers, The layer (Xα) is formed using a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier.
In the first production method, the composition (y) includes 100 parts by mass of the resin and 1 part by mass or more of the tackifier, and the composition (xα) includes 100 parts by mass of the adhesive resin and 1 part by mass or more of the tackifier. By including, the fall of the adhesive force with time can be suppressed effectively, and adhesive force can be maintained, without containing content of the tackifier contained in a layer (X (alpha)) excessively. As a result, it is possible to obtain a pressure-sensitive adhesive sheet that can achieve both suppression of the phenomenon that the adherend is clouded and high adhesive strength when it is attached to the adherend.
Although there is no restriction | limiting in particular in 1st manufacturing method, From a viewpoint of productivity, and a viewpoint of making it easy to form a recessed part and a flat surface in the surface ((alpha)) of a resin layer, the manufacturing method of the following 1st-1 aspects, And the manufacturing method of the I-2 aspect is preferable.

<The manufacturing method of an 1-1 aspect>
The production method of the I-1 aspect is a method having at least the following steps (1a) and (2a).
Step (1a): A coating film (xβ ′) composed of the composition (xβ), a coating film (y ′) composed of the composition (y), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating and forming a film (xα ′) in this order Step (2a): The coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1a) are simultaneously formed. Step of drying to form layer (Xβ), layer (Y1), and layer (Xα)

<Manufacturing method of I-2 aspect>
The manufacturing method of the 1-2nd aspect is a method which has the following process (1b) and (2b) at least.
Step (1b): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y ′) comprising the composition (y), and the composition (xα Step (2b): The coating film (y ′) and the coating film (xα ′) formed in the step (1b) are simultaneously dried to form a layer. Step of forming (Y1) and layer (Xα)

<Second manufacturing method>
In the second production method of the present invention, the layer (Xβ) is formed using a resin-containing composition (xβ), and the layer (Y1) is composed of 100 parts by mass of a resin and 1 part by mass or more of a tackifier. The composition (y1) is formed using a composition (y1) containing 15% by mass or more of fine particles, and the layer (Xα) contains 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier (xα). It forms using.
In the second production method, the composition (y1) contains 100 parts by mass of a resin, 1 part by mass or more of a tackifier, and 15% by mass or more of fine particles, and the composition (xα) contains 100 parts by mass of an adhesive resin. Part and 1 part by mass or more of a tackifier effectively suppresses a decrease in the adhesive strength over time, and does not excessively contain the content of the tackifier contained in the layer (Xα). Can be maintained. As a result, it is possible to obtain a pressure-sensitive adhesive sheet that achieves both suppression of the phenomenon of clouding of the adherend and high adhesive strength when adhered to the adherend, and is further excellent in air bleeding and blister resistance.
The second manufacturing method includes a layer (Xβ) mainly including a resin portion (X), a layer (Y1) including a particle portion (Y1), and mainly a pressure-sensitive adhesive sheet 1a in FIG. This is suitable for producing a pressure-sensitive adhesive sheet having a resin layer formed by forming a multilayer structure in which layers (Xα) including a resin portion (X) are laminated in this order.
Although there is no restriction | limiting in particular in the 2nd manufacturing method, From a viewpoint of productivity and the viewpoint of making it easy to form a recessed part and a flat surface in the surface ((alpha)) of a resin layer, the manufacturing method of the following II-1 aspect, And the manufacturing method of the II-2 aspect is preferable.

<The manufacturing method of II-1 aspect>
The production method of the II-1 embodiment is a method having at least the following steps (1A) and (2A).
Step (1A): A coating film (xβ ′) composed of the composition (xβ), a coating film (y1 ′) composed of the composition (y1), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating film (xα ′) in this order Step (2A): Simultaneously forming the coating film (xβ ′), coating film (y1 ′), and coating film (xα ′) formed in step (1A) Step of drying to form layer (Xβ), layer (Y1), and layer (Xα)

<The manufacturing method of II-2 aspect>
The production method of the II-2 embodiment is a method having at least the following steps (1B) and (2B).
Step (1B): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y1 ′) composed of the composition (y1), and the composition (xα Step (2B): The coating film (y1 ′) and the coating film (xα ′) formed in the step (1B) are simultaneously dried to form a layer. Step of Forming (Y1) and Layer (Xα) In the second production method, an irregular recess is effectively formed on the surface (α) of the layer (Xα) by the step (2A) or (2B). As a result of the formation of the irregular recess, the shape of the flat surface is also irregular.

[Configuration of pressure-sensitive adhesive sheet obtained by the production method of the present invention]
The pressure-sensitive adhesive sheet obtained by the production method of the present invention has a resin layer obtained by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a base material or a release material, The surface (α) of the layer (Xα) is an adhesive sheet having adhesiveness, and preferably the surface (α) has a recess and a flat surface.

FIG. 1 is a schematic cross-sectional view showing an example of the configuration of the pressure-sensitive adhesive sheet of the present invention.
Examples of the pressure-sensitive adhesive sheet according to one aspect of the present invention include a pressure-sensitive adhesive sheet 1a having a resin layer 12 on a substrate 11 as shown in FIG. 1A and a peeling as shown in FIG. An adhesive sheet 1 b having a resin layer 12 on the material 21 is exemplified.

As the pressure-sensitive adhesive sheet of one embodiment of the present invention, at least the surface (α) 12a of the layer (Xα) 12 opposite to the side on which the substrate 11 or the release material 21 is provided has adhesiveness, There is a flat surface 14.
Therefore, from the viewpoint of handleability, the pressure-sensitive adhesive sheet according to another aspect of the present invention further includes a release material 22 on the surface (α) 12a of the resin layer 12 with respect to the pressure-sensitive adhesive sheets 1a and 1b shown in FIG. It is preferable to have a structure such as the pressure-sensitive adhesive sheets 2a and 2b as shown in FIG. 1 (c) or (d).

In the pressure-sensitive adhesive sheet of one embodiment of the present invention, as shown in FIG. 1, it is preferable that the resin layer 12 includes a resin portion (X) containing a resin and a particle portion (Y) made of fine particles.
By including a particle part (Y) in the resin layer 12, it can be set as the adhesive sheet which improved blister resistance.
Details of the resin part (X) and the particle part (Y) are as described later.

In the pressure-sensitive adhesive sheet according to one embodiment of the present invention, the surface (β) 12b (hereinafter, also referred to as “surface (β)”) of the resin layer 12 on the side where the substrate 11 or the release material 21 is provided is also adhesive. You may have.
Since the surface (β) also has adhesiveness, if the adhesive sheets 1a and 2a shown in FIGS. 1A and 1C are used, the adhesiveness between the resin layer 12 and the substrate 11 is improved, and FIG. If it is the adhesive sheets 1b and 2b shown to b) and (d), it can be set as a double-sided adhesive sheet.

[Requirements for recesses and flat surfaces on the surface (α)]
In the pressure-sensitive adhesive sheet of the present invention, as shown in FIGS. 1A to 1D, the surface (α) 12 a of the resin layer 12 has a recess 13 and a flat surface 14.
The concave portion 13 present on the surface (α) serves as an air discharge passage for escaping an “air pool” generated when the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is attached to the adherend. Is responsible for.
On the other hand, the flat surface 14 existing on the surface (α) is a surface that directly contacts and adheres to the adherend when bonded to the adherend, and is a portion that affects the adhesive strength of the adhesive sheet.

FIG. 2 is a schematic plan view of the surface (α) when observed from the surface (α) side of the resin layer of the pressure-sensitive adhesive sheet of the present invention.
The concave portion present on the surface (α) of the resin layer is preferably an irregular concave portion 13 as shown in FIG. 2, but a regular concave portion may be present.
However, in one embodiment of the present invention, as shown in FIG. 2, it is preferable that one or more irregular recesses 13 exist on the surface (α) 12 a of the resin layer 12, and the irregular recess 13 is present. It is more preferable that a plurality exist.
Due to the presence of the irregular recesses on the surface (α) of the resin layer, it is possible to obtain a pressure-sensitive adhesive sheet that is further improved in air release and pressure-sensitive adhesive properties.
Further, the presence of a plurality of irregularly shaped recesses causes pressure to be applied from a certain direction, and even when the shape of a part of the recesses present on the surface (α) collapses, the surface (α) has a shape. The maintained recess 13 is likely to exist, and the air escape path can be prevented from disappearing.

  In addition, the length of the recess 13 when the recess 13 existing on the surface (α) is viewed in plan is not particularly limited. That is, the recess 13 includes a relatively long groove shape and a relatively short recess shape.

Further, the flat surface existing on the surface (α) of the resin layer is preferably an irregular flat surface 14 as shown in FIG. 2, but a regular flat surface may exist.
However, in one embodiment of the present invention, as shown in FIG. 2, it is preferable that one or more irregular flat surfaces 14 exist on the surface (α) 12 a of the resin layer 12. More preferably, a plurality of are present.
Unlike the surface of the pressure-sensitive adhesive layer formed using a release sheet having a general embossed pattern, the adhesive strength is locally increased due to the presence of an irregularly shaped flat surface on the surface (α) of the resin layer. It is possible to reduce the number of weak parts and parts having poor air release properties as much as possible. As a result, it is possible to uniformly exhibit excellent air bleeding and adhesive properties with respect to the surface (α) of the resin layer.

In the present invention, the term “indefinite shape” means that there is no regular shape such as a figure that can draw the center such as a circle or an ellipse, and a polygon, and the shape is not regular, and is similar to an individual shape. In particular, the shape of the recess 13 and the flat surface 14 shown in FIG.
On the other hand, examples of “standard” that is not “indefinite” include a circle, an ellipse, and a polygon. In this specification, a “polygon” is a figure in which a diagonal line can be drawn (without protruding outside), and the sum of internal angles is 180 × n (degrees) (n is a natural number) A figure surrounded by straight lines. The polygon includes those whose corners are curved in a round shape.

In the present invention, the determination of whether or not the surface (α) of the resin layer has an “indeterminate” recess or flat surface is determined from the surface (α) side of the resin layer, In principle, the shape of the recess is determined by visual observation or observation with a digital microscope (magnification: 30 to 100 times).
In the case of using a digital microscope, the focal point is moved in order from the top of the portion where the flat surface is supposed to exist on the surface (α) of FIG. It is appropriate to observe as follows.
If the focal point cannot be determined by the above method, a translucent adherend having a smooth surface is applied on the surface (α) of the resin layer using a squeegee so as not to apply a load as much as possible. You may judge by the method of observing the surface ((alpha)) of a resin layer through a translucent to-be-adhered body using a microscope, and confirming whether a recessed part and a flat surface exist.

However, 1 to 10 regions (D) surrounded by a rectangle of 8 mm vertically and 10 mm horizontally selected on the surface (α) are selected, and a recess or flat surface existing in each selected region (D) The shape of the surface may be determined by visual observation or observation with a digital microscope (magnification: 30 to 100 times) from the surface (α) side. That is, in any selected region, if there is an irregular recess or flat surface, it can be regarded as “the surface (α) has an irregular recess or flat surface”. Similarly, in any of the selected regions, if there are a plurality of irregularly shaped recesses or flat surfaces, it can be regarded as “a plurality of irregularly shaped recesses or flat surfaces exist on the surface (α)”. .
When observing the region (D), the entire surface of the region (D) selected at a low magnification may be observed at a time using a digital microscope.
In addition, the selected region (D) may be observed at a high magnification using a digital microscope. However, since the observation is performed at a high magnification, the region (D) is larger than the imageable region of the digital microscope. There is a case. In such a case, by using the image linking function of the digital microscope, a plurality of images adjacent to each other, which are arbitrarily selected, are acquired, and the plurality of images are connected to form a connected image. A portion surrounded by a rectangle of 8 mm in length and 10 mm in width arbitrarily selected from the connected image may be used as the region (D) for the above determination.
In the following description, in order to determine whether or not a certain requirement is satisfied, even when observing the selected area using a digital microscope, it may be determined from the connected image in the same manner as described above. .

In the description of the present specification, examples of the digital microscope used when observing various shapes include the product names “Digital Microscope VHX-1000” and “Digital Microscope VHX-5000” manufactured by Keyence Corporation. Can be mentioned.
Further, when observing various shapes, a method of directly observing the surface (α) with a digital microscope at the above magnification may be used, and an image is obtained using the digital microscope at the above magnification, and shown in the image A method of visually observing the shape of the concave portion and the flat portion may be used.

Moreover, it is preferable that the shape of the irregular recessed part which exists in the surface ((alpha)) can be visually recognized from the surface ((alpha)) side.
Similarly, it is preferable that the shape of the irregular flat surface existing on the surface (α) can be visually recognized from the surface (α) side.
In addition, in the adhesive sheets 2a and 2b in which the release material 22 is laminated on the surface (α) 12a of the resin layer 12 as shown in FIG. 1C or 1D, when the release material 22 is removed. The exposed surface (α) is observed visually.

In one embodiment of the present invention, the surface (α) may have a regular recess as well as an irregular recess 13 as shown in FIG.
However, the area ratio of the irregular recesses existing on the surface (α) to the total area 100% of recesses existing on the surface (α) is preferably 80 to 100%, more preferably 90 to 100%, More preferably, it is 95 to 100%, and still more preferably 100%.

Similarly, in one embodiment of the present invention, a regular flat surface may exist on the surface (α) together with the irregular flat surface 14 as shown in FIG.
However, the area ratio of the irregular flat surface existing on the surface (α) to the total area 100% of the flat surface existing on the surface (α) is preferably 80 to 100%, more preferably 90 to 100. %, More preferably 95 to 100%, and still more preferably 100%.

In addition, said "area ratio which a recessed part or a flat surface occupies" acquires the image of surface ((alpha)) using a digital microscope (magnification: 30-100 times), and performs image processing (binary value) with respect to the said image. Calculation).
Moreover, 1-10 area | regions (D) arbitrarily selected on the surface ((alpha)) 8 mm long * 10 mm wide are selected, and the image of the said area | region is selected using a digital microscope (magnification: 30-100 times). Obtain the value of “area ratio occupied by the recess or flat surface” of each area from the image, and calculate the average of the values of the selected 1 to 10 areas on the surface of the resin layer of the target adhesive sheet (α ) Present in “the ratio of the area occupied by the recess or flat surface”.
The area ratio of the flat surface existing on the surface (α) is preferably 50 to 90%, more preferably 55 to 80%, and still more preferably 60 to 70%.

  In one aspect of the present invention, from the viewpoint of forming a pressure-sensitive adhesive sheet with various properties such as air leakage and pressure-sensitive adhesive properties improved in a balanced manner, the shape of the concave portion and the flat surface existing on the surface (α) of the resin layer is constant. It is preferable that it does not have a shape that becomes a repeating unit.

Moreover, in one aspect of the present invention, from the viewpoint of a pressure-sensitive adhesive sheet in which various characteristics such as air escape and pressure-sensitive adhesive properties are improved in a balanced manner, there are a plurality of concave portions on the surface (α) of the resin layer, It is preferable that the position where a recessed part exists does not have periodicity. Further, from the same viewpoint, it is preferable that a plurality of flat surfaces exist on the surface (α) of the resin layer, and the positions where the plurality of flat surfaces exist do not have periodicity.
In the present invention, “the position where a plurality of recesses or flat surfaces are present has no periodicity” means that the positions where the plurality of recesses or flat surfaces exist are the same on the surface (α) of the resin layer. It means an irregular (random) state without a pattern.

  In addition, it is determined whether or not “the shape of the concave portion and the flat surface does not have a shape that is a constant repeating unit”, and “the position where the plurality of concave portions or the flat surface exists does not have periodicity”. This determination can be made by the same method as the above-described determination method of “whether there is an irregular recess or flat surface on the surface (α) of the resin layer”.

  Hereinafter, specific requirements regarding the recesses and the flat surface existing on the surface (α) will be described.

<Specific requirements for recesses on the surface (α)>
In one aspect of the present invention, it is preferable that one or more irregular recesses exist in a region (Q) surrounded by a square having a side of 1 mm arbitrarily selected on the surface (α) of the resin layer, More preferably, there are a plurality of irregularly shaped recesses.
The presence of one or more irregular recesses in the above-described region (Q) makes it possible to provide a pressure-sensitive adhesive sheet in which various properties such as air release properties and pressure-sensitive adhesive properties are improved in a well-balanced manner.

In one embodiment of the present invention, the recess 13 present on the surface (α) 12a of the resin layer 12 preferably has a maximum height difference of 0.5 μm or more.
The “recess” defined here refers to a recess having a maximum height difference of 0.5 μm or more, and a portion having a height difference of 0.5 μm or more may be present in any part of the recess. It is not necessary to have a height difference of 0.5 μm or more over the entire area.

FIG. 3 is a schematic cross-sectional view of the resin layer showing an example of the shape on the surface (α) side of the resin layer of the pressure-sensitive adhesive sheet of the present invention.
As the recess 13 shown in FIG. 3 (a), the shape of the conventional recess, 2 Tsunoyama part _(M 1), having a _{(M 2),} and a valley portion (N). In the present invention, the “maximum height difference” of the recess is the highest position (m) of the two peak portions (M ₁ ) and (M ₂ ) with respect to the thickness direction of the resin layer 12 (FIG. 3A ) Means the length of the difference (h) between the peak portion (M ₁ ) maximum point) and the lowest position (n) (the minimum point of the valley portion (N) in FIG. 3A).
In the case of FIG. 3B, a recess 131 having two peak portions (M ₁₁ ) and (M ₁₂ ) and a valley portion (N ₁ ), two peak portions (M ₁₂ ), and _{(M 13),} is believed to have two recesses of the recess 132 having a valley portion _{(N 2).} In this case, the length of the difference (h ₁ ) between the maximum point of the peak portion (M ₁₁ ) and the minimum point of the valley portion (N ₁ ) represents the maximum height difference of the recess 131, and the maximum of the peak portion (M ₁₃ ). The length of the difference (h ₂ ) between the point and the minimum point of the valley portion (N ₂ ) represents the maximum height difference of the recess 132.

  The maximum height difference of one concave portion is more preferably 1.0 μm or more from the viewpoint of improving the air release property of the pressure-sensitive adhesive sheet, maintaining the appearance of the pressure-sensitive adhesive sheet favorably, and from the viewpoint of shape stability of the pressure-sensitive adhesive sheet. The thickness is not more than the thickness of the resin layer, more preferably not less than 3.0 μm and not more than the thickness of the resin layer, still more preferably not less than 5.0 μm and not more than the thickness of the resin layer.

Moreover, as an average value of the width | variety of the said recessed part, from a viewpoint of the improvement of the air bleeding property of an adhesive sheet, and a viewpoint of making the adhesiveness of an adhesive sheet favorable, Preferably it is 1-500 micrometers, More preferably, it is 3-400 micrometers. Preferably it is 5-300 micrometers.
In the present invention, the width of the concave portion means the distance between the maximum points of the two peak portions, and in the concave portion 13 shown in FIG. 3A, the peak portion (M ₁ ) and the peak portion. The distance L to (M ₂ ) is indicated. Further, in the concave portion 131 shown in FIG. 3 (b) refers to the distance _{L 1} between the peak portions _{(M 11)} and the peak portions _{(M 12),} in the recess 132, the peak portions _{(M 13)} and the mountain It refers to the distance L ₂ with the part (M ₁₂ ).
In addition, when the pressure-sensitive adhesive sheet of the present invention is viewed in plan (when viewed from directly above), when the concave portion has a long side and a short side, the short side is referred to as a width.

  The ratio of the maximum height difference and the average width of the single recess [maximum height difference / width average value] (in the recess 13 shown in FIG. 3A, "h / L" is indicated) Is preferably 1/500 to 100/1, more preferably 3/400 to 70/3, and still more preferably, from the viewpoint of improving the air release property of the pressure-sensitive adhesive sheet and improving the pressure-sensitive adhesive property of the pressure-sensitive adhesive sheet. 1/60 to 10/1.

<Special requirements for flat surface existing on surface (α)>
In one embodiment of the present invention, a flat surface (f1) having a width capable of selecting a region surrounded by a circle having a diameter of at least 100 μm (preferably a diameter of 150 μm, more preferably a diameter of 200 μm) on the surface (α) of the resin layer. ) Is preferably present, more preferably a plurality of the flat surfaces (f1).
Since the flat surface (f1) is present on the surface (α), the adhesion portion with the adherend on the surface (α) is sufficient, so that the adhesion with the adherend can be improved, It can be set as the adhesive sheet with high adhesive force.
Further, in the above-described embodiment of the present invention, at least one flat surface (f1) exists in a region (D) of 8 mm long × 10 mm wide arbitrarily selected on the surface (α) of the resin layer. It is preferable that a plurality of the flat surfaces (f1) exist.
In the above-described embodiment, it is not necessary that all the flat surfaces existing on the surface (α) or the region (D) of the resin layer correspond to the flat surface (f1), and the surface (α) or the region ( The flat surface which exists in D) should just contain a flat surface (f1).

In another embodiment of the present invention, a flat surface having an area of 0.2 mm ² or more (preferably 0.3 mm ² or more, more preferably 0.4 mm ² or more) on the surface (α) of the resin layer. It is preferable that one or more (f2) exists, and it is more preferable that a plurality of the flat surfaces (f2) exist.
Since the flat surface (f2) is present on the surface (α), the adhesion portion with the adherend on the surface (α) is sufficient, so that the adhesion with the adherend can be improved, It can be set as the adhesive sheet with high adhesive force.
Moreover, in the said aspect of this invention, it is preferable that there exist 1 or more flat surfaces (f2) in the area | region (D) of 8 mm long * width 10 mm arbitrarily selected on the surface ((alpha)) of a resin layer. More preferably, there are a plurality of the flat surfaces (f2).
In the above-described embodiment, the entire flat surface existing on the surface (α) or the region (D) of the resin layer does not have to correspond to the flat surface (f2), and the surface (α) or region ( The flat surface which exists in D) should just contain a flat surface (f2).

  In addition, the flat surface (f1) and the flat surface (f2) described above correspond to the surface (α) of the resin layer or an arbitrarily selected region (D) of 8 mm in length × 10 mm in width on the surface (α). It is preferable that one or more surfaces (f12) exist, and it is more preferable that a plurality of the flat surfaces (f12) exist.

  In the present invention, whether or not the above-described flat surfaces (f1), (f2), and (f12) are present on the surface (α) or the region (D) is determined by the resin layer of the target adhesive sheet. An image obtained by observing a flat surface existing on the surface (α) or region (D) of the sample using a digital microscope (magnification: 30 to 100 times), and using the image analysis software based on the image, the diameter It may be determined whether a region surrounded by a 100 μm circle can be selected or the area of the flat surface may be calculated.

1 aspect of this invention WHEREIN: In the area | region (D) of 8 mm long * width 10 mm arbitrarily selected on the surface ((alpha)) of the said resin layer, with respect to the total area 100% of the recessed part which exists in the said area | region (D) It is preferable that there is a recess having an area of 70 to 99.99% (more preferably 85 to 99.99%).
Due to the presence of such a continuous recess, the pressure-sensitive adhesive sheet can be further improved in air bleeding.

[Requirements for cross section (P1)]
The pressure-sensitive adhesive sheet of the present invention arbitrarily selects a region (P) surrounded by a square having a side of 5 mm on the surface (α) of the resin layer, passes through each of the two diagonal lines of the square, and the surface (α). Among the two cross sections of the pressure-sensitive adhesive sheet obtained by cutting the region (P) in a plane perpendicular to the above, a plurality of recesses satisfying the following requirement (I) in at least one cross section (P1), and the following requirements There is a flat portion that satisfies (II).
Requirement (I): There are a plurality of recesses having a maximum height difference of 40% or more of the total thickness of the resin layer and having different shapes of cut portions on the surface (α) side of the cross section (P1). .
Requirement (II): on the surface (α) side of the cross section (P1), corresponds to a cut portion of the flat surface existing in the region (P), and is in contact with the resin layer of the base material or release material There is a flat portion substantially parallel to the surface.

First, with reference to FIG. 4 as appropriate, a flow until obtaining the “two cross sections of the pressure-sensitive adhesive sheet” will be described.
FIG. 4 is a view for explaining a method of obtaining “two cross sections of the pressure-sensitive adhesive sheet” defined in the present invention, and is a perspective view of the pressure-sensitive adhesive sheet of one embodiment of the present invention. In FIG. 4, as an example, a perspective view of the pressure-sensitive adhesive sheet 11 a having the same configuration as the pressure-sensitive adhesive sheet 1 a shown in FIG. Is omitted.

First, a region (P) surrounded by a square 50 having a side of 5 mm is arbitrarily selected on the surface (α) 12 a of the resin layer 12. At this time, the region (P) to be selected is not limited in terms of the position on the surface (α) 12a, the orientation of the square 50, and the like.
And the said adhesion | attachment at the time of cut | disconnecting area | region (P) by the plane which passes through each of the two diagonal lines 51 and 52 of the square 50 which comprises area | region (P), and becomes perpendicular | vertical with respect to surface ((alpha)) 12a. Consider two cross sections 61, 62 of the sheet.
That is, when the region (P) is cut in a plane perpendicular to the surface (α) 12a along the thickness direction A so as to pass through the diagonal line 51, the cross section 61 of the adhesive sheet is can get.
On the other hand, when the region (P) is cut in a plane perpendicular to the surface (α) 12a along the thickness direction A so as to pass through the diagonal line 52, a cross section 62 of the adhesive sheet is obtained. It is done.

In the present invention, for the two cross sections 61 and 62 of the pressure-sensitive adhesive sheet obtained in this way, a cross section in which a plurality of concave portions satisfying the requirement (I) and a flat portion satisfying the requirement (II) are present. Cross section (P1) ”.
That is, in the present invention, at least one of the cross sections 61 and 62 needs to be a cross section (P1) in which there are a plurality of concave portions that satisfy the requirement (I) and a flat portion that satisfies the requirement (II). .
Note that in one embodiment of the present invention, it is preferable that both of the two cross sections 61 and 62 correspond to the cross section (P1).

In the present invention, it is determined whether or not the two cross sections 61 and 62 correspond to a cross section (P1) where a plurality of concave portions satisfying the requirement (I) and a flat portion satisfying the requirement (II) exist. And the judgment whether the below-mentioned various requirements in the said cross section (P1) are satisfy | filled is judged from the image which acquired the target cross section using the scanning electron microscope (magnification: 100-1000 times).

FIG. 5 is an example of a schematic view of a cross section (P1) defined in the present invention.
As shown in FIG. 5, the cross section (P1) 60 obtained by the above method has at least a plurality of concave portions 13a and flat portions 14a on the surface (α) 12a side of the cross section (P1) 60. .
In addition, as shown in FIG. 5, the convex part 15a may exist in the surface ((alpha)) 12a side of the cross section (P1) 60.

In the cross section (P1) 60, as described in the requirement (I), the surface (α) 12a side of the cross section has a maximum height difference of 40% or more of the total thickness of the resin layer 12, There are a plurality of recesses 13a having different shapes.
The concave portion 13a having a maximum height difference of 40% or more of the total thickness of the resin layer 12 is a portion that plays a role as an air discharge passage that greatly affects the air release property of the adhesive sheet.
Since the shapes of the cut portions of the plurality of recesses 13a are different from each other, all the recesses appear to be the same when a force having a certain direction is applied to the pressure-sensitive adhesive sheet regardless of before and after the pressure-sensitive adhesive sheet is applied. It is possible to prevent a situation in which the groove that functions as an air discharge passage disappears. As a result, it is possible to obtain a pressure-sensitive adhesive sheet that is extremely excellent in air bleeding.

From the above viewpoint, in one embodiment of the present invention, in the cross section (P1) 60, the shape of the cut portion of the plurality of recesses 13a existing on the surface (α) 12a side defined by the requirement (I) is It is preferable to include a concave portion that is indefinite.
The “indefinite shape” here has the same meaning as described above.

In the present invention, the determination of “whether it corresponds to a recess having a maximum height difference of 40% or more of the total thickness of the resin layer 12”, “whether the shape of the cut portions of the plurality of recesses is different from each other”, and The determination of “whether or not the shape of the cut portion corresponds to an indented recess” is determined from the image obtained by using the scanning electron microscope for the section (P1) 60 as described above.
In addition, among the above, the judgment of “whether or not the shapes of the cut portions of the plurality of recesses are different from each other” is made, for example, by superimposing the shapes of the cut portions of the two recesses to be shown in the above image. If the number of coincident portions is less than 90% of the total, it may be determined that “the two recessed portions have different shapes of the cut portions”.

In the cross section (P1) 60, as described in the requirement (II), on the surface (α) 12a side of the cross section, a cut portion of the flat surface 14 existing in the region (P) as shown in FIG. Correspondingly, there is a flat portion 14a that is substantially parallel to the surface of the substrate or release material in contact with the resin layer 12.
The flat portion 14a corresponds to a cut surface of the flat surface 14 existing on the surface (α), and corresponds to a portion substantially parallel to the surface of the base material or the release material in the cross section (P1) 60.
That is, in the cross section (P1) 60 shown in FIG. 5, the straight line e _α that passes through the flat portion 14 a is substantially parallel to the straight line e _β that passes through the surface of the base material 11 in contact with the resin layer 12. Therefore, the flat portion 14a, such as shown in FIG. 4, is distinguished from the formed convex portion 15a as swell upward with respect to the straight line e _alpha.

  In the present invention, “substantially parallel” refers to a straight line passing through the flat portion 14a existing on the surface (α) side of the cross section (P1) and a straight line passing through the surface of the base material or release material in contact with the resin layer. Of course, when the angle formed is a slight inclination that can be regarded as substantially parallel (for example, the formed angle is 5 degrees or less, preferably 2 degrees or less). Case).

Further, from the viewpoint of making the pressure-sensitive adhesive sheet with improved air release and pressure-sensitive adhesive properties, in the cross section (P1) 60, a plurality of the flat portions 14a are provided on the surface (α) 12a side of the cross section (P1) 60. It is preferable to exist, and it is more preferable that the positions of the plurality of flat portions 14a existing on the surface (α) 12a side have no periodicity.
Note that “the position of the flat portion has no periodicity” means that the positions where the plurality of flat portions are present do not have the same repeating pattern and are irregular (random).

In the cross section (P1) 60, when there are a plurality of flat portions 14a on the surface (α) 12a side of the cross section (P1) 60, the plurality of flat portions 14a satisfy the requirement (II). For this reason, it can be said that the distance to each said base material or peeling material of the said some flat part 14a which exists in the surface ((alpha)) 12a side is the same.
In the present invention, “the same distance to the base material or the release material of each of the plurality of flat portions” means that the difference in distance to the base material or the release material of the two flat portions is a target. A range that is less than 5% (preferably less than 2%) with respect to the average value of the distance is included.

Furthermore, it is preferable to satisfy at least one of the following requirements (Ia) and (IIa) from the viewpoint of making a pressure-sensitive adhesive sheet with improved air bleeding and pressure-sensitive adhesive properties, and both of the following requirements (Ia) and (IIa) It is more preferable to satisfy.
Requirement (Ia): In the cross section (P1) 60, the width of the concave portion 13a existing on the surface (α) with respect to the horizontal width (E _α ) 100 of the resin layer 12 on the surface (α) 12a side. The proportion of the total is 10 to 90.
Requirement (IIa): In the cross section (P1) 60, the flat portion 14a existing on the surface (α) occupies the horizontal width (E _α ) 100 of the resin layer 12 on the surface (α) 12a side. The ratio is 10-90.

The “horizontal width (E _α ) of the resin layer on the surface (α) side” defined by the requirements (Ia) and (IIa) is a length indicated by E _α in FIG. For example, if the shape of the selected cross section (P1) 60 is a rectangle, it corresponds to the horizontal length of the rectangle.

The ratio of the total width of the recesses 13a existing on the surface (α) 12a defined by the requirement (Ia) is 10 to 90, preferably 20 to 80, more preferably 25 to 70, Preferably it is 30-60.
As the ratio of the total width of the recesses 13a increases, the air detachability improves. As the ratio decreases, the ratio of the flat portion 14a increases, and thus the adhesive property improves.
As described above, in the present invention, the “width of the concave portion” refers to the distance L between the _two peak portions (M ₁ ) and the peak portion (M ₂ ) as shown in FIG. . Therefore, since the “width of the concave portion” is a length including a part of the convex portion 15a, when the convex portion 15a is present on the surface (α), it is defined by the requirement (Ia). The sum of the ratio and the ratio specified in the requirement (IIa) does not become “100”, which is the same as the horizontal width (E _α ).

As a ratio which the said flat part which exists in the surface ((alpha)) which prescribes | regulates by requirements (IIa), is 10-90, Preferably it is 20-80, More preferably, it is 25-70, More preferably, it is 30-60. It is.
As the proportion occupied by the flat portion increases, the adhesive property improves, and as the proportion decreases, the proportion occupied by the concave portion increases, so that air bleedability is improved.

In one aspect of the present invention, in the above-described cross section, from the viewpoint of a pressure-sensitive adhesive sheet in which there are a plurality of recesses defined in the requirement (I) and a flat portion satisfying the requirement (II), the recesses are It is preferably not formed using a release material having an emboss pattern.
The “concave portion formed using a release material having an embossed pattern” includes, for example, the following and is distinguished from the concave portion of the above aspect.
A recess formed by pressing the release sheet with the embossed pattern against the flat surface of the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition, and transferring the embossed pattern.
-Using a release sheet with an embossed pattern on the release treatment surface, applying the adhesive composition to the release treatment surface to form an adhesive layer, and then removing the release sheet, the adhesive layer Recesses that appear on the surface of
Such a recess causes a number of problems as listed as problems relating to the pressure-sensitive adhesive sheet described in Patent Document 1.

In one embodiment of the present invention, from the viewpoint of forming a pressure-sensitive adhesive sheet having a concave portion and a flat surface satisfying the above-mentioned requirements on the surface (α) of the resin layer, the concave portion is formed by self-forming the resin layer. It is preferable that
In the present invention, “self-forming” means a phenomenon that creates a disordered shape naturally in the autonomous formation process of the resin layer. It means a phenomenon that naturally forms a disordered shape in the autonomous formation process of the resin layer by drying the coated film.
In addition, the shape of the recess formed by self-forming the resin layer in this way can be adjusted to some extent by adjusting the drying conditions and the type and content of components in the composition that is the resin layer forming material. Although it is possible, it can be said that, unlike the groove formed by the transfer of the embossed pattern, “it is virtually impossible to reproduce the same shape”. Therefore, it can be said that the recessed part formed by self-formation of the resin layer is indefinite.
In addition, since the irregular concave portion is formed, the shape of the flat surface becomes irregular.

The formation process of the recess formed by the self-formation of the resin layer is considered as follows.
First, at the time of forming the coating film made of the composition that becomes the resin layer forming material, in the step of drying the coating film, shrinkage stress is generated inside the coating film, and the bonding strength of the resin is weakened. Cracks occur in the coating film. And it is thought that the resin around the cracked portion flows into the space temporarily generated by the cracking, so that a recess is formed on the surface (α) of the resin layer.
After forming two-layer coating films with different resin contents, the two-layer coating films are dried at the same time, resulting in a shrinkage stress difference inside the coating film and causing cracks in the coating film. It will be easier.

In addition, from the viewpoint of facilitating the formation of the concave portion, it is preferable to adjust the following matters as appropriate. It is considered that the factors due to these matters act in a complex manner and the concave portions are easily formed. By the way, the suitable aspect of each matter for making it easy to form a recessed part is as the description by the applicable item mentioned later.
-The type of resin, constituent monomer, molecular weight, and content contained in the composition that is the coating film forming material.
-The kind of crosslinking agent and the kind of solvent which are contained in the composition which is a film-forming material.
-Viscosity and solid content concentration of the composition which is a material for forming the coating film.
-The thickness of the coating film to be formed. (In the case of multiple layers, the thickness of each coating film)
-Drying temperature and drying time of the formed coating film.

In the formation of the pressure-sensitive adhesive layer of a general pressure-sensitive adhesive sheet, the above items are often set appropriately for the purpose of forming a pressure-sensitive adhesive layer having a flat surface.
On the other hand, in the present invention, the above items are set so that a concave portion that can contribute to the improvement of the air release property of the pressure-sensitive adhesive sheet is intentionally formed. Is completely different.

The above items are preferably set as appropriate in consideration of the fluidity of the resin contained in the coating film to be formed.
For example, when the composition contains fine particles, by adjusting the viscosity of the coating film composed of a composition containing many fine particles to an appropriate range, while maintaining the predetermined fluidity of the fine particles in the coating film, Mixing with other coating films (coating films containing a large amount of resin) can be moderately suppressed. By adjusting in this way, in the coating film containing a lot of resin, there is a tendency that cracks are generated in the horizontal direction and the concave portions are easily formed.
As a result, on the surface (α), the ratio of the recessed portions to be formed can be increased, and the ratio of the recessed portions connected to each other can be increased, so that a pressure-sensitive adhesive sheet having more excellent air release properties can be obtained.

Moreover, among the above matters, it is preferable to appropriately adjust the type, constituent monomer, molecular weight, and resin content of the resin so that the resin contained in the coating film containing a large amount of resin has appropriate viscoelasticity.
In other words, by appropriately hardening the hardness of the coating film (hardness determined by factors such as the viscoelasticity of the resin and the viscosity of the coating solution), the shrinkage stress of the resin part (X) becomes strong, and a recess is easily formed. Become. The harder the coating film, the stronger the shrinkage stress and the easier it is to generate recesses. Further, if the elasticity of the resin is increased too much, the adhesive strength of the resin layer formed from the coating film tends to decrease. Considering this point, it is preferable to appropriately adjust the viscoelasticity of the resin.
In addition, when the composition or coating film contains fine particles, by adjusting the dispersion state of the fine particles, the degree of swelling of the resin layer by the fine particles and the self-forming ability of the recesses can be adjusted, resulting in It is considered that the concave portion can be easily formed on the surface (α) and can be adjusted.

Furthermore, it is preferable to appropriately set the above items in consideration of the crosslinking rate of the formed coating film (or composition that is a forming material).
That is, when the crosslinking speed of the coating film is too high, the coating film may be cured before the recess is formed. It also affects the size of cracks in the coating.
The crosslinking rate of the coating film can be adjusted by appropriately setting the type of the crosslinking agent and the solvent in the composition as the forming material, the drying time and the drying temperature of the coating film.

In the case where the resin layer is a layer including a resin portion (X) containing resin and a particle portion (Y) made of fine particles, the resin layer formed by the above-described self-formation is shown in FIG. As shown in (d) and FIG. 5, the particle portion (Y) is such that the proportion of the particle portion (Y) is smaller than the others in the portion where the concave portion exists on the surface (α). There is a tendency to be distributed.
This is because, in the process of self-forming the resin layer, when the recess is formed on the surface (α) of the resin layer, the fine particles that existed at the position where the recess was formed move. It is thought that it became distribution.

As an aspect of the distribution of the particle part (Y) in the resin layer formed by such self-formation, an aspect as shown in FIG.
That is, as shown in FIG. 5, in the cross section 60, the distribution in the horizontal direction of the particle portion (Y) contained in the resin layer 12 is non-uniform, and the recess 13a exists on the surface (α) 12a. On the other hand, the distribution of the particle portion (Y) in the region (s1) located below the concave portion 13a in the thickness direction is the same horizontal position as the region (s1), and a flat portion is formed on the surface (α) 12a. It is preferable that the amount is smaller than the region (s2).
Such uneven distribution of the particle portion (Y) is peculiar to the resin layer formed by self-formation.

  Hereinafter, each configuration used in the present invention will be described.

〔Base material〕
There is no restriction | limiting in particular as a base material used by this invention, For example, the base material etc. which laminated the paper base material, the resin film or sheet, the paper base material with resin, etc. are mentioned, The use of the adhesive sheet of 1 aspect of this invention It can be selected as appropriate according to the conditions.
Examples of the paper constituting the paper substrate include thin paper, medium quality paper, high quality paper, impregnated paper, coated paper, art paper, sulfuric acid paper, glassine paper and the like.
Examples of the resin constituting the resin film or sheet include polyolefin resins such as polyethylene and polypropylene; vinyl such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer. Polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; urethane resin such as polyurethane and acrylic modified polyurethane; polymethylpentene; Polysulfone; Polyetheretherketone; Polyethersulfone; Polyphenylene sulfide; Polyimide resins such as polyetherimide and polyimide; Polyamide resins, acrylic resins, fluorine-based resins.
Examples of the base material obtained by laminating a paper base material with a resin include laminated paper obtained by laminating the paper base material with a thermoplastic resin such as polyethylene.

Among these substrates, a resin film or sheet is preferable, a film or sheet made of a polyester resin is more preferable, and a film or sheet made of polyethylene terephthalate (PET) is still more preferable.
In addition, when the pressure-sensitive adhesive sheet of the present invention is used for an application requiring heat resistance, a film or sheet composed of a resin selected from polyethylene naphthalate and a polyimide resin is preferable, and an application requiring weather resistance. When used in a film, a film or sheet composed of a resin selected from polyvinyl chloride, polyvinylidene chloride, acrylic resin, and fluororesin is preferable.

Although the thickness of a base material is suitably set according to the use of the adhesive sheet of this invention, from a viewpoint of handleability and economical efficiency, Preferably it is 5-1000 micrometers, More preferably, it is 10-500 micrometers, More preferably, 12- The thickness is 250 μm, more preferably 15 to 150 μm.
In addition, the base material may further contain various additives such as an ultraviolet absorber, a light stabilizer, an antioxidant, an antistatic agent, a slip agent, an antiblocking agent, and a colorant.

In addition, the base material used in the present invention is preferably a non-breathable base material from the viewpoint of improving the blister resistance of the resulting pressure-sensitive adhesive sheet. Specifically, a metal is formed on the surface of the above-described resin film or sheet. A substrate having a layer is preferred.
Examples of the metal contained in the metal layer include metals having metallic luster such as aluminum, tin, chromium, and titanium.
As a method for forming the metal layer, for example, a method of depositing the metal by a PVD method such as vacuum deposition, sputtering, or ion plating, or a metal foil made of the metal is attached using a general adhesive. Although the method etc. are mentioned, the method of vapor-depositing the said metal by PVD method is preferable.

Furthermore, when using a resin film or sheet as a base material, from the viewpoint of improving the adhesion with the resin layer laminated on these resin films or sheets, the surface of the resin film or sheet is oxidized or uneven. Surface treatment by a method or the like, or primer treatment may be performed.
Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet), hot air treatment, ozone, and ultraviolet irradiation treatment. Examples of the unevenness method include sand blast method and solvent treatment method. Etc.

[Release material]
As the release material used in the present invention, a release sheet that has been subjected to a double-sided release process, a release sheet that has been subjected to a single-sided release process, or the like is used.
In addition, the said peeling process surface does not have uneven | corrugated shape, and the peeling material (for example, the peeling material in which the embossing pattern is not given) which is flat is preferable.
Examples of the base material for the release material include the above-described paper base material, resin film or sheet used as the base material included in the pressure-sensitive adhesive sheet of one embodiment of the present invention, and a base material obtained by laminating a paper base material with a resin. It is done.
Examples of the release agent include rubber elastomers such as silicone resins, olefin resins, isoprene resins, and butadiene resins, long chain alkyl resins, alkyd resins, and fluorine resins.
The thickness of the release material is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 170 μm, and still more preferably 35 to 80 μm.

[Resin layer]
As shown in FIG. 1, the resin layer 12 included in the pressure-sensitive adhesive sheet of the present invention preferably includes a resin part (X) containing a resin and a particle part (Y) made of fine particles.
The resin part (X) indicates a part containing components other than the fine particles contained in the resin layer. That is, not only the resin but also components other than fine particles, such as a tackifier, a crosslinking agent, and a general-purpose additive, are included in the “resin portion (X)”.
On the other hand, the particle portion (Y) indicates a portion composed of fine particles contained in the resin layer.

By including the particle portion (Y) in the resin layer, the shape maintaining property after pasting can be improved, and when the obtained pressure-sensitive adhesive sheet is used at high temperature, the generation of blisters is effectively suppressed. be able to.
The configuration of the distribution of the resin portion (X) and the particle portion (Y) in the resin layer 12 may be a configuration in which the resin portion (X) and the particle portion (Y) are substantially evenly distributed. In particular, it may be configured to be divided into a part mainly composed of the resin part (X) and a part mainly composed of the particle part (Y).

It is preferable that the resin layer which the adhesive sheet of this invention has has a space | gap part (Z) further besides resin part (X) and particle | grain part (Y). By having a void portion (Z) in the resin layer, the blister resistance of the pressure-sensitive adhesive sheet can be improved.
The void portion (Z) includes voids that exist between the fine particles, and voids that exist in the secondary particles when the fine particles are secondary particles.
When the resin layer has a multilayer structure, the resin portion (X) flows into the void portion (Z) even if the void portion (Z) exists immediately after the formation of the resin layer or immediately after the formation. In some cases, the voids disappear and the resin layer has no void portion (Z).
However, even when the void portion (Z) that has been present in the resin layer for a period of time disappears, the pressure-sensitive adhesive sheet according to one embodiment of the present invention has a recess on the surface (α) of the resin layer. Therefore, the air release property is good, and the resin layer has a particle portion (Y), so that the blister resistance is also excellent.

Further, the shear storage modulus at 100 ° C. of the resin layer of the pressure-sensitive adhesive sheet of the present invention is preferably 9.0 × 10 ³ Pa or more, more preferably from the viewpoint of improving the air bleeding property and blister resistance of the pressure-sensitive adhesive sheet. Is 1.0 × 10 ⁴ Pa or more, more preferably 2.0 × 10 ⁴ Pa or more.
In the present invention, the shear storage modulus at 100 ° C. of the resin layer is measured by measuring at a frequency of 1 Hz using a viscoelasticity measuring device (for example, device name “DYNAMIC ANALYZER RDA II” manufactured by Rheometrics). Means the value.

  The thickness of the resin layer is preferably 1 to 300 μm, more preferably 5 to 150 μm, and still more preferably 10 to 75 μm.

  In the pressure-sensitive adhesive sheet of the present invention, at least the surface (α) of the resin layer opposite to the side on which the base material or release material is provided has adhesiveness, but the base material or release material is provided. The surface (β) of the resin layer on the side may also have adhesiveness.

The pressure-sensitive adhesive force on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is preferably 0.5 N / 25 mm or more, more preferably 2.0 N / 25 mm or more, more preferably 3.0 N / 25 mm or more, even more preferably. Is 4.0 N / 25 mm or more, more preferably 7.0 N / 25 mm or more.
Moreover, when the surface (β) of the resin layer also has adhesiveness, the adhesive force on the surface (β) preferably belongs to the above range.
In addition, the value of the said adhesive force of an adhesive sheet means the value measured by the method as described in an Example.

<Multilayer structure of resin layer>
The resin layer in the present invention is composed of three or more kinds of layers having a resin layer obtained by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a base material or a release material. A multilayer structure.
As a resin layer which is such a multilayer structure, a layer (Xβ) mainly including a resin portion (X) from the side where a base material or a release material is provided, such as the adhesive sheet 1a of FIG. Preferably, a multilayer structure in which a layer (Y1) containing a particle portion (Y) and a layer (Xα) mainly containing a resin portion (X) are laminated in this order can be mentioned.
In addition, in the structure of the multilayer structure of the resin layer, the boundary between the two layers to be laminated may not be discriminated, and a mixed layer may be used.
That is, in the resin layer 12 included in the pressure-sensitive adhesive sheet 1a in FIG. 1, the boundary between the layer (Xβ) and the layer (Y1) and / or the boundary between the layer (Y1) and the layer (Xα) cannot be determined. A mixed layer structure may be used.

  Hereinafter, the resin layer 12 composed of three layers of the layer (Xβ), the layer (Y1), and the layer (Xα) included in the pressure-sensitive adhesive sheet 1a of FIG. explain.

The layer (Xβ) and the layer (Xα) are layers mainly including the resin portion (X), but may include a particle portion (Y). However, the content of the particle part (Y) in the layer (Xβ) and the layer (Xα) is each independently 15 masses with respect to the total mass (100 mass%) of the layer (Xβ) or the layer (Xα). % And less than the content of the resin in the layer (Xβ) or the layer (Xα).
That is, the layer (Xβ) and the layer (Xα) are distinguished from the layer (Y1) in terms of the content of the particle portion (Y).
In addition, the layer (Xβ) and the layer (Xα) may further include the above-described void portion (Z) in addition to the resin portion (X) and the particle portion (Y).

As content of the resin part (X) in a layer (X (beta)) and a layer (X (alpha)), it is 85 mass normally with respect to the total mass (100 mass%) of a layer (X (beta)) or a layer (X (alpha)) each independently. %, Preferably 87 to 100% by mass, more preferably 90 to 100% by mass, still more preferably 95 to 100% by mass, and still more preferably 100% by mass.
In addition, said "content of resin part (X)" is resin, a tackifier, a crosslinking agent, and general-purpose addition which comprises the resin part (X) contained in a layer (X (beta)) or a layer (X (alpha)). It means the total content of components other than fine particles such as an agent.

The content of the fine particles constituting the particle portion (Y) in the layer (Xβ) and the layer (Xα) is independently from the total mass (100% by mass) of the layer (Xβ) or the layer (Xα). However, it is preferably 0 to 13% by mass, more preferably 0 to 10% by mass, still more preferably 0 to 5% by mass, and still more preferably 0% by mass.
In the present invention, “the content of fine particles in the layer (Xβ) and the layer (Xα)” refers to the total amount (100% by mass (100% by mass) of the layer (Xβ) or the forming material of the layer (Xα). However, it can also be regarded as the content of fine particles in a)) excluding a diluting solvent.

As content of resin in a layer (X (alpha)), it is 30-100 mass% normally with respect to the total mass (100 mass%) of a layer (X (alpha)), Preferably it is 40-100 mass%, More preferably, it is 50-100. It is 60 mass%, More preferably, it is 60-100 mass%.
On the other hand, the content of the resin in the layer (Xβ) is usually 50 to 100% by mass, preferably 65 to 100% by mass, and more preferably 75% with respect to the total mass (100% by mass) of the layer (Xβ). -100 mass%, More preferably, it is 85-100 mass%.
In addition, in this invention, "content of the resin in a layer (X (beta)) and a layer (X (alpha))""is the total amount (100 mass% (100 mass% () of the said layer (X (beta)) or the forming material of a layer (X (alpha))). However, it can be regarded as the content of the resin in a)) except for the dilution solvent.

The layer (Y1) may be a layer including the particle portion (Y) together with the resin portion (X), and may further be a layer having a void portion (Z).
The content of the fine particles constituting the particle portion (Y) in the layer (Y1) is 15% by mass or more with respect to the total mass (100% by mass) of the layer (Y1), preferably 20 to 100. The mass% is more preferably 25 to 90 mass%, still more preferably 30 to 85 mass%, and still more preferably 35 to 80 mass%.

  As content of resin in a layer (Y1), it is 0-85 mass% normally with respect to the total mass (100 mass%) of a layer (Y1), Preferably it is 1-80 mass%, More preferably, it is 5-75. It is 10 mass%, More preferably, it is 10-70 mass%, More preferably, it is 20-65 mass%.

  In the present invention, “the content of the fine particles in the layer (Y1)” and “the content of the resin in the layer (Y1)” are the total amount (100% by mass) of the composition that is a forming material of the layer (Y1). % (Excluding the diluting solvent)) can be regarded as the content of fine particles or resin.

In one embodiment of the present invention, the layer (Xα) is preferably a layer formed of a composition (xα) containing an adhesive resin and a tackifier and having a fine particle content of less than 15% by mass. .
Similarly, the layer (Xβ) is also preferably a layer formed of a composition (xβ) containing a resin and containing a fine particle of less than 15% by mass.
Moreover, the said layer (Y1) is a layer formed from the composition (y) containing resin and a tackifier.
In addition, about a suitable aspect (a content component, content, etc.) of a composition (x (alpha)), a composition (x (beta)), and a composition (y1), it is as below-mentioned.

<Resin part (X)>
The resin part (X) constituting the resin layer is a part containing components other than the fine particles contained in the resin layer, and is distinguished from the particle part (Y) in that respect.
The resin part (X) may contain a tackifier, a crosslinking agent, a general-purpose additive and the like together with the resin.

The resin content in the resin part (X) is usually 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more, based on the total amount (100% by mass) of the resin part (X). More preferably, it is 55 mass% or more, More preferably, it is 60 mass% or more, More preferably, it is 70 mass% or more, Preferably it is 100 mass% or less, More preferably, it is 99.9 mass% or less.
In the present invention, the value of the content of the resin in the resin composition as the material for forming the resin portion (X) can also be regarded as the “content of the resin in the resin portion (X)”.

The resin contained in the resin portion (X) preferably contains an adhesive resin from the viewpoint of expressing the adhesiveness on the surface (α) of the formed resin layer.
In particular, as in the pressure-sensitive adhesive sheet 1a in FIG. 1A, the layer (Xβ), the layer (Y1), and the layer (Xα) are arranged in this order from the side on which the base material or release material is provided. From the above viewpoint, at least the layer (Xα) contains an adhesive resin. Moreover, it is preferable that at least the layer (Xα) and the layer (Xβ) contain an adhesive resin from the viewpoint of configuring the double-sided pressure-sensitive adhesive sheet and improving the adhesion to the base material.

(Adhesive resin)
Examples of the adhesive resin include acrylic resins, urethane resins, rubber resins, and silicone resins.
Among these adhesive resins, it is preferable to contain an acrylic resin from the viewpoint of good adhesive properties and weather resistance and facilitating the formation of recesses on the surface (α) of the resin layer.
The content of the acrylic resin is preferably 25 to 100% by mass, more preferably 50 to 100% by mass, and still more preferably 70% with respect to the total amount (100% by mass) of the resin contained in the resin part (X). -100 mass%, More preferably, it is 80-100 mass%, More preferably, it is 100 mass%.

Moreover, from the viewpoint of facilitating the formation of the recesses on the surface (α) of the resin layer, the resin portion (X) preferably contains a resin having a functional group, and more preferably contains an acrylic resin having a functional group. .
In particular, as in the pressure-sensitive adhesive sheet 1a in FIG. 1A, the layer (Xβ), the layer (Y1), and the layer (Xα) are arranged in this order from the side on which the base material or release material is provided. From the above viewpoint, at least the layer (Y1) preferably contains a resin having a functional group.
The functional group is a group that is a starting point of crosslinking with a crosslinking agent, and examples thereof include a hydroxy group, a carboxy group, an epoxy group, an amino group, a cyano group, a keto group, and an alkoxysilyl group. preferable.

The resin part (X) preferably further contains a crosslinking agent together with the resin having the functional group. In particular, when the resin layer is the multilayer structure described above, at least the layer (Y1) preferably contains a crosslinking agent together with the resin having the functional group.
Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, an aziridine crosslinking agent, and a metal chelate crosslinking agent.

  Examples of the isocyanate-based crosslinking agent include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and xylylene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate; alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate; In addition, biuret bodies, isocyanurate bodies of these compounds, and adduct bodies that are a reaction product of low molecular active hydrogen-containing compounds (ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, etc.); Is mentioned.

  Examples of the epoxy-based cross-linking agent include ethylene glycol glycidyl ether, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-m-xylylenediamine, Examples include 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, diglycidyl aniline, diglycidyl amine and the like.

  Examples of the aziridine-based crosslinking agent include diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane tri-β-aziridinylpropionate, tetramethylolmethanetri-β-aziridinyl. Propionate, toluene-2,4-bis (1-aziridinecarboxamide), triethylenemelamine, bisisophthaloyl-1- (2-methylaziridine), tris-1- (2-methylaziridine) phosphine, And trimethylolpropane tri-β- (2-methylaziridine) propionate.

Examples of the metal chelate-based crosslinking agent include chelate compounds in which the metal atom is aluminum, zirconium, titanium, zinc, iron, tin, etc. From the viewpoint of easily forming a recess on the surface (α) of the resin layer, aluminum Chelate type crosslinking agents are preferred.
Examples of the aluminum chelate-based crosslinking agent include diisopropoxy aluminum monooleyl acetoacetate, monoisopropoxy aluminum bis oleyl acetoacetate, monoisopropoxy aluminum monooleate monoethyl acetoacetate, diisopropoxy aluminum monolauryl acetoacetate, Examples include isopropoxyaluminum monostearyl acetoacetate and diisopropoxyaluminum monoisostearyl acetoacetate.

In addition, you may use these crosslinking agents individually or in combination of 2 or more types.
Among these, from the viewpoint of facilitating formation of recesses on the surface (α) of the resin layer, the resin portion (X) is one or more selected from a metal chelate crosslinking agent, an epoxy crosslinking agent, and an aziridine crosslinking agent. It is preferable that a metal chelate crosslinking agent is included, and it is more preferable that an aluminum chelate crosslinking agent is included.

  The content of the crosslinking agent in the resin part (X) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 100 parts by mass of the resin having a functional group contained in the resin part (X). -10 parts by mass, more preferably 0.3-7.0 parts by mass.

Moreover, as one aspect of the present invention, it is preferable that the resin portion (X) contains both a metal chelate-based crosslinking agent and an epoxy-based crosslinking agent from the viewpoint of facilitating formation of recesses on the surface (α) of the resin layer. .
When the resin part (X) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent, from the above viewpoint, the content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the resin part (X) [metal chelate system The cross-linking agent / epoxy-based cross-linking agent] is preferably 10/90 to 99.5 / 0.5, more preferably 50/50 to 99.0 / 1.0, and still more preferably 65/35 by mass ratio. To 98.5 / 1.5, more preferably 75/25 to 98.0 / 2.0.

  The resin portion (X) preferably further contains a tackifier together with the adhesive resin from the viewpoint of further improving the adhesive properties of the surface (α). In particular, when the resin layer is the above-described multilayer structure, the layer (Xα) preferably contains an adhesive resin and a tackifier.

(Tackifier)
The tackifier used in the present invention is a component that assists in improving the adhesive strength of the adhesive resin, and refers to an oligomer having a mass average molecular weight (Mw) of usually less than 10,000, which is distinguished from the above-mentioned adhesive resin. It is what is done.
The mass average molecular weight (Mw) of the tackifier is preferably 400 to 8000, more preferably 5000 to 5000, and more preferably 800 to 3500.

Examples of tackifiers include rosin resins such as rosin resins, rosin ester resins, and rosin-modified phenol resins; hydrogenated rosin resins obtained by hydrogenating these rosin resins; terpene resins, aromatic modified terpene resins, and terpene phenols. Terpene resins such as styrene resins; hydrogenated terpene resins obtained by hydrogenating these terpene resins; styrene obtained by copolymerizing a styrene monomer such as α-methylstyrene or β-methylstyrene with an aliphatic monomer Hydrogenated styrene resins obtained by hydrogenating these styrene resins; C5 systems obtained by copolymerizing C5 fractions such as pentene, isoprene, piperine, 1.3-pentadiene produced by thermal decomposition of petroleum naphtha Petroleum resin and hydrogenated petroleum resin of this C5 petroleum resin; indene and vinyli produced by thermal decomposition of petroleum naphtha And C9 petroleum resins obtained by copolymerizing C9 fractions such as toluene and hydrogenated petroleum resins.
The tackifiers used in the present invention may be used alone or in combination of two or more different softening points and structures.

The softening point of the tackifier is preferably 80 ° C or higher, more preferably 80 to 180 ° C, still more preferably 83 to 170 ° C, and still more preferably 85 to 150 ° C.
In the present invention, the “softening point” of the tackifier means a value measured according to JIS K2531.
Moreover, when using 2 or more types of several tackifier, it is preferable that the weighted average of the softening point of these several tackifier belongs to the said range.

  When the tackifier is contained in the resin part (X), the content of the tackifier is preferably 1 part by mass or more with respect to 100 parts by mass of the adhesive resin contained in the resin part (X). Preferably it is 1-200 mass parts, More preferably, it is 3-150 mass parts, More preferably, it is 5-90 mass parts.

Moreover, the resin part (X) may contain general-purpose additives other than the above-mentioned crosslinking agents and tackifiers.
General-purpose additives include, for example, antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators, ultraviolet absorbers, and the like.
These general-purpose additives may be used alone or in combination of two or more.
When these general-purpose additives are contained, the content of each general-purpose additive is preferably 0.0001 to 60 parts by mass, more preferably 0.001 to 50 parts by mass with respect to 100 parts by mass of the resin. .

The said resin contained in resin part (X) may be only 1 type, and may be used in combination of 2 or more type.
The material for forming the resin portion (X) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is preferably a pressure-sensitive adhesive containing a pressure-sensitive adhesive resin having a functional group, and an acrylic resin (A) having a functional group (below) It is more preferable that it is an acrylic pressure-sensitive adhesive containing simply an “acrylic resin (A)”, and it is an acrylic pressure-sensitive adhesive containing an acrylic resin (A) having a functional group and a crosslinking agent (B). More preferably.
The acrylic pressure-sensitive adhesive may be either a solvent type or an emulsion type.
Hereinafter, the above-mentioned acrylic pressure-sensitive adhesive suitable for the resin part (X) as a forming material will be described.

Examples of the acrylic resin (A) contained in the acrylic pressure-sensitive adhesive include a polymer having a structural unit derived from an alkyl (meth) acrylate having a linear or branched alkyl group and a cyclic structure ( Examples thereof include a polymer having a structural unit derived from (meth) acrylate.
The mass average molecular weight (Mw) of the acrylic resin (A) is preferably 50,000 to 1,500,000, more preferably 150,000 to 1,300,000, still more preferably 250,000 to 1,100,000, still more preferably 350,000 to 90. Ten thousand.

As the acrylic resin (A), a structural unit (a1) derived from an alkyl (meth) acrylate (a1 ′) having an alkyl group having 1 to 18 carbon atoms (hereinafter also referred to as “monomer (a1 ′)”), And an acrylic copolymer (A1) having a structural unit (a2) derived from the functional group-containing monomer (a2 ′) (hereinafter also referred to as “monomer (a2 ′)”). More preferably, it is a combination (A1).
The content of the acrylic copolymer (A1) is preferably 50 to 100% by mass, more preferably 70 to 100%, based on the total amount (100% by mass) of the acrylic resin (A) in the acrylic adhesive. It is 80 mass%, More preferably, it is 80-100 mass%, More preferably, it is 90-100 mass%.
In addition, the form of copolymerization of the acrylic copolymer (A1) is not particularly limited, and may be any of a block copolymer, a random copolymer, and a graft copolymer.

As carbon number of the alkyl group which a monomer (a1 ') has, from a viewpoint of the improvement of an adhesive characteristic, More preferably, it is 4-12, More preferably, it is 4-8, More preferably, it is 4-6.
Examples of the monomer (a1 ′) include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, and tridecyl ( Examples include meth) acrylate and stearyl (meth) acrylate.
Among these, butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate are preferable, and butyl (meth) acrylate is more preferable.

  The content of the structural unit (a1) is preferably 50 to 99.5% by mass, more preferably 60 to 99% by mass, with respect to the total structural unit (100% by mass) of the acrylic copolymer (A1). More preferably, it is 70-95 mass%, More preferably, it is 80-93 mass%.

Examples of the monomer (a2 ′) include a hydroxy group-containing monomer, a carboxy group-containing monomer, an epoxy group-containing monomer, an amino group-containing monomer, a cyano group-containing monomer, a keto group-containing monomer, and an alkoxysilyl group-containing monomer. .
Among these, a carboxy group-containing monomer is more preferable.
Examples of the carboxy group-containing monomer include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid, and (meth) acrylic acid is preferred.

  The content of the structural unit (a2) is preferably 0.5 to 50% by weight, more preferably 1 to 40% by weight, based on all the structural units (100% by weight) of the acrylic copolymer (A1). More preferably, it is 5-30 mass%, More preferably, it is 7-20 mass%.

The acrylic copolymer (A1) may have a structural unit (a3) derived from another monomer (a3 ′) other than the monomers (a1 ′) and (a2 ′).
Examples of the other monomer (a3 ′) include cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, and dicyclopentenyl. Examples thereof include (meth) acrylate having a cyclic structure such as oxyethyl (meth) acrylate and imide (meth) acrylate, vinyl acetate, acrylonitrile, and styrene.

The content of the structural unit (a3) is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, and still more preferably based on the total structural unit (100% by mass) of the acrylic copolymer (A1). Is 0 to 10% by mass, more preferably 0 to 5% by mass.
In addition, you may use the above-mentioned monomer (a1 ')-(a3') individually or in combination of 2 or more types.

  The method for synthesizing the acrylic copolymer (A1) component is not particularly limited. For example, the raw material monomer is dissolved in a solvent and solution polymerization is performed in the presence of a polymerization initiator, a chain transfer agent, or the like. In the presence of a method, an emulsifier, a polymerization initiator, a chain transfer agent, a dispersant, and the like, it is produced by emulsion polymerization in an aqueous system using raw material monomers.

Examples of the cross-linking agent (B) contained in the acrylic pressure-sensitive adhesive include those described above. From the viewpoint of improving the pressure-sensitive adhesive property, and the viewpoint of easily forming a recess on the surface (α) of the resin layer. From the above, it is preferable to include one or more selected from metal chelate crosslinking agents, epoxy crosslinking agents, and aziridine crosslinking agents, more preferably to include metal chelating crosslinking agents, and to include aluminum chelating crosslinking agents. Is more preferable.
Moreover, as one aspect of the present invention, as a crosslinking agent (B), a metal chelate-based crosslinking agent and an epoxy-based crosslinking are used from the viewpoint of improving the shape maintainability of a plurality of recesses present on the surface (α) of the resin layer. It is preferable to include both agents.

  The content of the crosslinking agent (B) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the acrylic resin (A) in the acrylic adhesive. More preferably, it is 0.3 to 7.0 parts by mass.

  When a metal chelate crosslinking agent and an epoxy crosslinking agent are used in combination, the content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent [metal chelate crosslinking agent / epoxy crosslinking agent] is preferably a mass ratio, preferably 10/90 to 99.5 / 0.5, more preferably 50/50 to 99.0 / 1.0, still more preferably 65/35 to 98.5 / 1.5, still more preferably 75/25 98.0 / 2.0.

  The acrylic pressure-sensitive adhesive used in one embodiment of the present invention may contain a general-purpose additive as long as the effects of the present invention are not impaired. Examples of the general-purpose additive include those described above, and the content of the general-purpose additive is also as described above.

Moreover, it is preferable that the acrylic adhesive used in one embodiment of the present invention further contains a tackifier from the viewpoint of further improving the adhesive properties of the surface (α). Examples of the tackifier include those described above, and the content of the tackifier is also as described above.
The composition (xβ) preferably contains substantially no tackifier.

In the acrylic pressure-sensitive adhesive used in one embodiment of the present invention, a pressure-sensitive resin other than the acrylic resin (A) (for example, urethane-based resin, rubber-based resin, silicone-based resin, etc.) within a range that does not impair the effects of the present invention. ) May be contained.
The content of the acrylic resin (A) in the acrylic pressure-sensitive adhesive is preferably 50 to 100% by mass, more preferably 70%, based on the total amount (100% by mass) of the adhesive resin contained in the acrylic pressure-sensitive adhesive. -100 mass%, More preferably, it is 80-100 mass%, More preferably, it is 100 mass%.

<Particle part (Y)>
In the resin layer which the adhesive sheet of 1 aspect of this invention has, it is preferable that the particle part (Y) which consists of microparticles | fine-particles is included.
The average particle size of the fine particles is preferably 0.01 from the viewpoint of improving the air bleeding property and blister resistance of the pressure-sensitive adhesive sheet, and from the viewpoint of facilitating the formation of recesses and flat surfaces on the surface (α) of the resin layer. It is -100 micrometers, More preferably, it is 0.05-25 micrometers, More preferably, it is 0.1-10 micrometers.

The fine particles used in one embodiment of the present invention are not particularly limited, and include inorganic particles such as silica particles, metal oxide particles, barium sulfate, calcium carbonate, magnesium carbonate, glass beads, smectite, and organic particles such as acrylic beads. Can be mentioned.
Among these fine particles, one or more selected from silica particles, metal oxide particles, and smectites are preferable, and silica particles are more preferable.

The silica particles used in one embodiment of the present invention may be either dry silica or wet silica.
In addition, the silica particles used in one embodiment of the present invention include organic modified silica surface-modified with an organic compound having a reactive functional group, inorganic modified silica surface-treated with an inorganic compound such as sodium aluminate or sodium hydroxide In addition, organic-inorganic modified silica surface-treated with these organic compounds and inorganic compounds, organic-inorganic modified silica surface-treated with an organic-inorganic hybrid material such as a silane coupling agent, and the like may be used.
In addition, the mixture which consists of 2 or more types may be sufficient as these silica particles.

The mass concentration of silica in the silica particles is preferably 70 to 100% by mass, more preferably 85 to 100% by mass, and still more preferably 90 to 100% by mass with respect to the total amount (100% by mass) of the silica particles. .
The volume average secondary particle size of the silica particles used in one embodiment of the present invention is such that the pressure-sensitive adhesive sheet has improved air bleeding and blister resistance, and the surface (α) of the resin layer has recesses and flat surfaces. From the viewpoint of facilitating formation, the thickness is preferably 0.5 to 10 μm, more preferably 1 to 8 μm, and still more preferably 1.5 to 5 μm.
In the present invention, the value of the volume average secondary particle diameter of the silica particles is a value obtained by measuring the particle size distribution by a Coulter counter method using a multisizer three machine or the like.

  Examples of the metal oxide particles include particles made of metal oxide selected from titanium oxide, alumina, boehmite, chromium oxide, nickel oxide, copper oxide, titanium oxide, zirconium oxide, indium oxide, zinc oxide, and composite oxides thereof. The sol particle | grains which consist of these metal oxides are also included.

  Examples of the smectite include montmorillonite, beidellite, hectorite, saponite, stevensite, nontronite, and soconite.

The mass retention after heating the resin layer of the pressure-sensitive adhesive sheet of one embodiment of the present invention at 800 ° C. for 30 minutes is preferably 3 to 90% by mass, more preferably 5 to 80% by mass, and still more preferably 7 to 70%. It is 9 mass%, More preferably, it is 9-60 mass%.
The mass retention rate can be regarded as indicating the content (% by mass) of fine particles contained in the resin layer.
If the said mass retention is 3 mass% or more, it can become an adhesive sheet excellent in air bleeding property and blister resistance. Moreover, at the time of manufacture of the pressure-sensitive adhesive sheet of the present invention, concave portions are easily formed on the surface (α) of the resin layer. On the other hand, if the mass retention is 90% by mass or less, the resin layer has high film strength, excellent water resistance and chemical resistance, and a flat surface is easily formed on the surface (α) of the resin layer.

[Method for producing pressure-sensitive adhesive sheet of the present invention]
Next, the manufacturing method of the adhesive sheet of this invention is demonstrated.
In the production method of the present invention, the layer (Xβ) and the layer (Y1) are formed on the substrate or the release material from the viewpoint of productivity, and from the viewpoint of easily forming the recess and the flat surface on the surface (α) of the resin layer. ) And a layer (Xα) are laminated in this order, and at least the surface (α) of the layer (Xα) is a pressure-sensitive adhesive sheet manufacturing method.
The manufacturing method of the present invention includes the following first manufacturing method and second manufacturing method.

<First manufacturing method>
In the first production method, the layer (Xβ) is formed using a composition (xβ) containing a resin, and the layer (Y1) is a composition containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier. The layer (Xα) is formed using a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier.
In the first production method, the composition (y) includes 100 parts by mass of the resin and 1 part by mass or more of the tackifier, and the composition (xα) includes 100 parts by mass of the adhesive resin and 1 part by mass or more of the tackifier. By including, the fall of the adhesive force with time can be suppressed effectively, and adhesive force can be maintained, without containing content of the tackifier contained in a layer (X (alpha)) excessively. As a result, it is possible to obtain a pressure-sensitive adhesive sheet that can achieve both suppression of the phenomenon that the adherend is clouded and high adhesive strength when it is attached to the adherend.

(Layer (Xβ), Composition (xβ))
The layer (Xβ) is formed using a composition (xβ) containing a resin.
The content of the resin in the composition (xβ) is usually 30% by mass or more, preferably 40% by mass or more, based on the total amount of the composition (x) (100% by mass (excluding the dilution solvent)), More preferably, it is 50 mass% or more, More preferably, it is 55 mass% or more, More preferably, it is 60 mass% or more, More preferably, it is 70 mass% or more, Preferably it is 100 mass% or less, More preferably, it is 99.9. It is 95 mass% or less, More preferably, it is 95 mass% or less.

  Examples of the resin contained in the composition (xβ) include resins constituting the above-described resin portion (X), preferably an adhesive resin, more preferably an adhesive resin having a functional group, The acrylic resin (A) having a functional group is further preferable, and the above-mentioned acrylic copolymer (A1) is still more preferable.

It is preferable that the composition (xβ) further contains a crosslinking agent (B).
Examples of the crosslinking agent contained in the composition (xβ) include the crosslinking agent contained in the resin part (X) described above. The composition (xβ) is a metal chelate crosslinking agent or an epoxy crosslinking agent. , And an aziridine-based crosslinking agent are preferably included, more preferably a metal chelate-based crosslinking agent, and still more preferably an aluminum chelate-based crosslinking agent.
Furthermore, as one aspect of the present invention, the composition (y) preferably contains both a metal chelate crosslinking agent and an epoxy crosslinking agent. When the composition (y) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent, a suitable content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the composition (y) [metal chelate crosslinking agent / Epoxy crosslinking agent] is as described above.
The content of the crosslinking agent is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, and still more preferably 0.1 to 100 parts by mass of the resin contained in the composition (xβ). 3 to 7.0 parts by mass.

  The composition (xβ) can contain a tackifier, but when it has a substrate on the surface (β) side, the adhesion between the substrate and the surface (β) of the resin layer is good. From the viewpoint of improving the peelability of the release material with respect to the surface (β), when the release material is provided on the surface (β) side, the content of the tackifier is preferably small. Specifically, the content of the tackifier is preferably 0 to 10 parts by mass, more preferably 0 to 5 parts by mass, and still more preferably 0 with respect to 100 parts by mass of the resin contained in the composition (xβ). -1 part by mass, more preferably 0-0.1 part by mass, and it is preferable that the tackifier is not substantially contained.

Further, the composition (xβ) may contain the fine particles described above.
However, the content of the fine particles in the composition (xβ) is less than 15% by mass and is less than the content of the resin contained in the composition (xβ).
The content of the fine particles in the specific composition (xβ) is less than 15% by mass with respect to the total amount of the composition (x) (100% by mass (excluding the diluting solvent)), preferably Is 0 to 13% by mass, more preferably 0 to 10% by mass, still more preferably 0 to 5% by mass, and still more preferably 0% by mass.

(Layer (Y1), Composition (y))
A layer (Y1) is formed using the composition (y) containing 100 mass parts of resin and 1 mass part or more of tackifiers from a viewpoint of improving the adhesion characteristic of the surface ((alpha)) more.
Examples of the resin contained in the composition (y) include the same resins as those contained in the composition (xβ) described above. Like the composition (xβ), a resin having a functional group is preferable. The acrylic resin (A) having a functional group is more preferable, and the above-mentioned acrylic copolymer (A1) is more preferable.
The content of the resin in the composition (y) is usually 0 to 85% by mass, preferably 1 to 80% by mass with respect to the total amount of the composition (y) (100% by mass (excluding the dilution solvent)). %, More preferably, it is 5-75 mass%, More preferably, it is 10-70 mass%, More preferably, it is 20-65 mass%.

The tackifier used in the present invention is a component that assists in improving the adhesive strength of the resin, and refers to an oligomer having a mass average molecular weight (Mw) of usually less than 10,000, and is distinguished from the above-mentioned adhesive resin. Is.
The detail of the said resin and tackifier is as above-mentioned, and they can be used individually or in combination of 2 or more types.
The content of the tackifier in the layer (Y1) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 20 parts by mass with respect to 100 parts by mass of the resin from the viewpoint of further improving the adhesive properties. The upper limit is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and still more preferably 90 parts by mass or less.
In addition, the content of the tackifier contained in the composition (y) is preferably 400 parts by mass or less, more preferably 150 parts by mass or less, and more preferably 100 parts by mass or less, further based on 100 parts by mass of the resin in the composition (y). Preferably it is 80 parts by mass or less, more preferably 50 parts by mass or less, and the lower limit thereof is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and still more preferably 10 parts by mass. More than part by mass.

  The layer (Y1) may be a layer including the particle portion (Y) together with the resin portion (X), and may further be a layer having a void portion (Z).

It is preferable that the composition (y) further contains a crosslinking agent (B).
As a crosslinking agent contained in a composition (y), the same thing as the crosslinking agent contained in the above-mentioned resin part (X) is mentioned. Among these, the composition (y) preferably contains one or more selected from metal chelate crosslinking agents, epoxy crosslinking agents, and aziridine crosslinking agents, and more preferably contains a metal chelate crosslinking agent. .
Furthermore, as one aspect of the present invention, the composition (y) preferably contains both a metal chelate crosslinking agent and an epoxy crosslinking agent. When the composition (y) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent, a suitable content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the composition (y) [metal chelate crosslinking agent / Epoxy crosslinking agent] is as described above.
The content of the crosslinking agent in the composition (y) is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin contained in the composition (y). Part, more preferably 0.3 to 7.0 parts by weight.

(Layer (Xα), Composition (xα))
From the viewpoint of further improving the adhesive properties of the surface (α), particularly the layer (Xα), particularly from the viewpoint of effectively suppressing a decrease in adhesive strength over time, 100 parts by mass of the adhesive resin and 1 part by mass or more of the tackifier And a composition (xα) containing

The content of the tackifier in the layer (Xα) is preferably 5 parts by mass or more, more preferably 10 parts by mass with respect to 100 parts by mass of the adhesive resin, from the viewpoint of further improving the adhesive properties of the surface (α). More preferably, it is 15 parts by mass or more, and the upper limit thereof is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and still more preferably 90 parts by mass or less.
In addition, the content of the tackifier contained in the composition (xα) is preferably 400 parts by mass or less, more preferably 150 parts by mass or less, with respect to 100 parts by mass of the adhesive resin in the composition (xα). The lower limit is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and even more preferably. Is 10 parts by mass or more.
Moreover, content of the tackifier with respect to 100 mass% of the total mass of the said resin layer becomes like this. Preferably it is 2-60 mass%, More preferably, it is 4-60 mass%, More preferably, it is 6-20 mass%.

  The content ratio [(xα) / (y)] of the tackifier contained in the composition (xα) and the tackifier contained in the composition (y) is a mass ratio, preferably 100/500 to 500/500. 100/10, More preferably, it is 100 / 300-100 / 20, More preferably, it is 100 / 200-100 / 30, More preferably, it is 100 / 100-100 / 40.

The details of the adhesive resin and the tackifier are as described above.
The adhesive resin preferably contains an acrylic resin having a functional group as described above from the viewpoint of further improving the adhesive properties and facilitating the formation of the recess and the flat surface on the surface (α) of the resin layer.
The functional group is a group that is a starting point of crosslinking with a crosslinking agent, and examples thereof include a hydroxy group, a carboxy group, an epoxy group, an amino group, a cyano group, a keto group, and an alkoxysilyl group. preferable.
From the above viewpoint, the content of the acrylic resin is preferably 25 to 100% by mass, more preferably 50 to 100% by mass with respect to the total amount (100% by mass) of the resin contained in the resin part (X). More preferably, it is 70-100 mass%, More preferably, it is 80-100 mass%, More preferably, it is 100 mass%.

It is preferable that the composition (xα) further contains a crosslinking agent (B).
Examples of the crosslinking agent contained in the composition (xα) include the crosslinking agent contained in the resin part (X) described above. The composition (xβ) comprises a metal chelate crosslinking agent and an epoxy crosslinking agent. , And an aziridine-based crosslinking agent are preferably included, more preferably a metal chelate-based crosslinking agent, and still more preferably an aluminum chelate-based crosslinking agent.
Furthermore, as one aspect of the present invention, the composition (xα) preferably contains both a metal chelate crosslinking agent and an epoxy crosslinking agent. When the composition (xα) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent, a suitable content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the composition (xα) [metal chelate crosslinking agent / Epoxy crosslinking agent] is as described above.
The content of the crosslinking agent is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, and still more preferably 0.1 to 100 parts by mass of the resin contained in the composition (xα). 3 to 7.0 parts by mass.

<Mode of Production Method I>
Although there is no restriction | limiting in particular in 1st manufacturing method, From a viewpoint of productivity, and a viewpoint of making it easy to form a recessed part and a flat surface in the surface ((alpha)) of a resin layer, the manufacturing method of the following 1st-1 aspects, And the manufacturing method of the I-2 aspect is preferable.

<The manufacturing method of an 1-1 aspect>
The production method of the 1-1st aspect includes at least the following steps (1a) and (2a).
Step (1a): A coating film (xβ ′) composed of the composition (xβ), a coating film (y ′) composed of the composition (y), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating and forming a film (xα ′) in this order Step (2a): The coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1a) are simultaneously formed. Step of drying to form layer (Xβ), layer (Y1), and layer (Xα)

<Step (1a)>
The step (1a) comprises a coating film (xβ ′) composed of the composition (xβ), a coating film (y ′) composed of the composition (y), and a composition (xα) on the substrate or the release material. In this step, the coating film (xα ′) is formed by laminating in this order.
The composition (xβ) is a material for forming the resin part (X), and preferably contains a crosslinking agent together with the above-mentioned resin, and may further contain a tackifier and the above-mentioned general-purpose additives.
The composition (y) is a material for forming the particle portion (Y), but may further contain a crosslinking agent and the above-mentioned general-purpose additives in addition to the resin and the tackifier. The composition (y) containing components other than fine particles such as these resins is a forming material for the particle portion (Y) and a forming material for the resin portion (X).
The composition (xα) is a material for forming the resin portion (X), and contains a tackifier together with the adhesive resin, but may further contain a crosslinking agent and the above-mentioned general-purpose additives.

(Formation method of coating film (xβ ′), coating film (y ′), and coating film (xα ′))
In forming the coating film, in order to facilitate the formation of the coating film, the composition (xβ), the composition (y), and the composition (xα) are mixed with a solvent, It is preferable to do.
Examples of such a solvent include water and organic solvents.
Examples of the organic solvent include toluene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, methanol, ethanol, isopropyl alcohol, t-butanol, s-butanol, acetylacetone, cyclohexanone, n-hexane, and cyclohexane. . These solvents may be used alone or in combination of two or more.

The coating films (xβ ′), (y ′) and (xα ′) formed in the step (1a) are formed by laminating in this order.
As a method of forming the coating films (xβ ′), (y ′), and (xα ′), after forming (xβ ′), the coating film (y ′) is formed on the coating film (xβ ′), and A method of sequentially forming a coating film (xα ′) on the coating film (y ′) may be used, and from the viewpoint of productivity, the coating film (xβ ′), the coating film (y ′), and the coating film (xα ′). Alternatively, a method may be used in which a multi-layer coater is used for simultaneous coating.
Examples of the coater used for sequential formation include spin coater, spray coater, bar coater, knife coater, roll coater, knife roll coater, blade coater, gravure coater, curtain coater, and die coater.
Examples of the coater used for simultaneous application with a multilayer coater include a curtain coater and a die coater. Among these, a die coater is preferable from the viewpoint of operability.

The coating amount of the coating film (xα ′) is preferably 1.5 to 800 g / m ² , more preferably 5 to 500 g / m ² , and still more preferably 10 to 300 g, from the viewpoint of improving air bleeding and adhesive properties. / M ² , more preferably 20 to 200 g / m ² .
The coating amount of the coating film (y ′) is preferably 1.5 to 800 g / m ² , more preferably 5 to 500 g / m ² , and still more preferably 10 to 300 g, from the viewpoint of improving air bleeding and adhesive properties. / M ² , more preferably 20 to 200 g / m ² .
The ratio [(xα ′) / (y ′)] of the coating amount between the coating film (xα ′) and the coating film (y ′) is preferably 100/5 to 5 from the viewpoint of improving the air release property and the adhesive property. 100/2000, more preferably 100/50 to 100/1500, and still more preferably 100/100 to 100/1000.

In step (1a), after forming at least one of the coating film (xβ ′), coating film (y ′), and coating film (xα ′), before proceeding to step (2a), the coating film is cured. You may give the predrying process of the grade which does not advance reaction.
For example, the pre-drying treatment may be performed each time after the coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) are formed. ) And the coating film (y ′), the coating film (xα ′) may be formed after the above pre-drying treatment.
In the step (1a), the drying temperature at the time of performing the pre-drying treatment is usually appropriately set in a temperature range in which the formed coating film does not proceed, but preferably in the step (2a). Below the drying temperature. The specific drying temperature indicated by the prescription “below the drying temperature in step (2a)” is preferably 10 to 45 ° C., more preferably 10 to 34 ° C., and further preferably 15 to 30 ° C.

<Step (2a)>
In the step (2a), the coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1a) are simultaneously dried, and the layer (Xβ), the layer (Y1), and This is a step of forming the layer (Xα).
In the step (2a), by simultaneously drying the formed coating film (xβ ′), coating film (y ′), and coating film (xα ′), a resin layer that can effectively suppress a decrease in adhesive strength over time. Surface (α) is formed.

The drying temperature in the step (2a) is preferably 35 to 200 ° C., more preferably 60 to 180 ° C., still more preferably 70 to 160 ° C., and still more preferably from the viewpoint of effectively suppressing a decrease in adhesive strength with time. Preferably it is 80-140 degreeC.
When the drying temperature is 35 ° C. or higher, a pressure-sensitive adhesive sheet with good air release properties can be obtained. On the other hand, if the said drying temperature is 200 degrees C or less, the malfunction that the base material and peeling material which an adhesive sheet has shrink | contracts can be suppressed.
Note that the lower the drying temperature, the greater the difference in height of the recesses formed, but the number of recesses formed tends to decrease.

  In addition, in the step (2a), the void portion (Z) is more preferably selected from silica particles, metal oxide particles, and smectite as fine particles contained in the composition (y). It can be formed easily.

<Manufacturing method of I-2 aspect>
The production method of the I-2 aspect has at least the following steps (1b) and (2b).
Step (1b): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y ′) comprising the composition (y), and the composition (xα Step (2b): The coating film (y ′) and the coating film (xα ′) formed in the step (1b) are simultaneously dried to form a layer. Step of forming (Y1) and layer (Xα)

<Step (1b)>
In the step (1b), on the surface of the substrate or the release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y ′) composed of the composition (y), and the composition ( In this step, a coating film (xα ′) made of xα) is laminated in this order.
In the step (1b), the “layer (Xβ) mainly including the resin portion (X)” is formed by drying the coating film (xβ ′) made of the composition (xβ) including the resin as the main component. be able to.
Since the layer (Xβ) is formed from the composition (xβ), the layer (Xβ) may contain a crosslinking agent, a general-purpose additive and the like in addition to the resin. The content of the resin portion (X) in the layer (Xβ) is as described above.

As a method for forming the layer (Xβ), a coating film (xβ ′) made of a composition (xβ) containing a resin is formed on a base material or a release material, and the coating film (xβ ′) is dried. can do.
There is no restriction | limiting in particular as drying temperature at this time, Preferably it is 35-200 degreeC, More preferably, it is 60-180 degreeC, More preferably, it is 70-160 degreeC, More preferably, it is 80-140 degreeC.

In the production method of the I-2 aspect, the coating film (y ′) and the coating film (xα ′) are not formed on the coating film (xβ ′) but on the layer (Xβ) obtained after drying. It differs from the manufacturing method of the above-mentioned I-1 aspect by the point formed in order.
Also in the step (1b), it is preferable that the composition (y) and the composition (xα) are mixed with the above-described solvent to form a solution of the composition and then applied.
As a method for forming the coating film (y ′) and the coating film (xα ′), after forming the coating film (y ′) on the layer (Xβ), the coating film (xα ′) is formed on the coating film (y ′). ) May be sequentially formed using the above-described coater, or may be a method in which the coating film (y ′) and the coating film (xα ′) are simultaneously applied and formed using the above-described multilayer coater. Good.

Coating amount of coating film (xα ′), coating amount of coating film (y ′), and ratio of coating amount of coating film (xα ′) to coating film (y ′) [(xα ′) / (y ′) ] Is the same as the above-mentioned step (1a).
In the step (1b), after the formation of the coating film (y ′) or after the formation of the coating film (y ′) and the coating film (xα ′), the coating film is cured before moving to the step (2b). You may give the predrying process of the grade which does not advance reaction.
The conditions for the pre-drying treatment in this step (1b) are the same as those in the above-described step (1a).

<Step (2b)>
Step (2b) is a step of simultaneously drying the coating film (y ′) and coating film (xα ′) formed in step (1b) to form a layer (Y1) and a layer (Xα).
The suitable range of the drying temperature in the step (2b) is the same as that in the above step (1b).
By the step (2a), the surface (α) of the resin layer capable of effectively suppressing a decrease in adhesive strength with time is formed.

<Second manufacturing method>
In the second production method, the layer (Xβ) is formed using the resin-containing composition (xβ), the layer (Y1) includes 100 parts by mass of the resin, and 1 part by mass or more of the tackifier, It is formed using a composition (y1) containing 15% by mass or more of fine particles, and the layer (Xα) is formed using a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier. Form.
In the second production method, the composition (y1) contains 100 parts by mass of a resin, 1 part by mass or more of a tackifier, and 15% by mass or more of fine particles, and the composition (xα) contains 100 parts by mass of an adhesive resin. Part and 1 part by mass or more of a tackifier effectively suppresses a decrease in the adhesive strength over time, and does not excessively contain the content of the tackifier contained in the layer (Xα). Can be maintained. As a result, it is possible to obtain a pressure-sensitive adhesive sheet that achieves both suppression of the phenomenon of clouding of the adherend and high adhesive strength when adhered to the adherend, and is further excellent in air bleeding and blister resistance.
According to the second production method, as in the pressure-sensitive adhesive sheet 1a of FIG. 1 (a), a layer (Xβ) mainly containing the resin part (X), a layer (Y1) containing the particle part (Y1), and A pressure-sensitive adhesive sheet having a resin layer formed by forming a multilayer structure in which layers (Xα) mainly including the resin portion (X) are laminated in this order can be easily produced.

In the second production method, the layer (Xβ) and the composition (xβ) are the same as in the first production method, and the preferred examples and preferred ranges are also the same. That is, the resin contained in the composition (xβ) is preferably an adhesive resin.
In the second production method, the layer (Xα) and the composition (xα) are the same as in the first production method, and the preferred examples and the preferred ranges are also the same.
The layer (Y1) is applied by replacing the layer (Y) in the first manufacturing method with the layer (Y1).
Further, in the second manufacturing method, the method for forming the coating film (xβ ′) and the coating film (xα ′) is the same as the first manufacturing method, and the method for forming the coating film (y1 ′) The method for forming the coating film (y ′) in the production method is read as the method for forming the coating film (y1 ′).

(Composition (y1))
The composition (y1) is a material for forming the particle portion (Y), and includes 100 parts by mass of a resin, 1 part by mass or more of a tackifier, and 15% by mass or more of fine particles.
The resin contained in the composition (y1) is preferably an adhesive resin.
From the viewpoint of fine particle dispersibility, the composition (y1) preferably contains a resin and a tackifier together with the fine particles, and further contains a crosslinking agent. Further, a general-purpose additive may be included.
In addition, components (resin, tackifier, cross-linking agent, and general-purpose additive) other than the fine particles contained in the composition (y1) serve as a forming material for the resin portion (X).

The content of the tackifier in the layer (Y1) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 20 parts by mass with respect to 100 parts by mass of the resin from the viewpoint of further improving the adhesive properties. The upper limit is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and still more preferably 90 parts by mass or less.
In addition, the content of the tackifier contained in the composition (y1) is preferably 400 parts by mass or less, more preferably 150 parts by mass or less, more preferably 100 parts by mass or less, with respect to 100 parts by mass of the resin in the composition (y1). Preferably it is 80 parts by mass or less, preferably 50 parts by mass or less, and the lower limit thereof is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and even more preferably 10 parts by mass. That's it.
Moreover, content of the tackifier with respect to 100 mass% of the total mass of the said resin layer becomes like this. Preferably it is 2-60 mass%, More preferably, it is 4-60 mass%, More preferably, it is 6-20 mass%.

Examples of the fine particles contained in the composition (y1) include those described above. From the viewpoint of forming a void portion (Z) in the resin layer and improving the blister resistance, silica particles are used. One or more selected from metal oxide particles and smectite are preferred.
The content of the fine particles in the composition (y1) is such that the amorphous recesses and the flat surface formed by self-formation of the resin layer are easily formed on the surface (α) of the resin layer. Although it is 15 mass% or more with respect to the whole quantity (100 mass% (however, except a dilution solvent)) of (y1), Preferably it is 20-100 mass%, More preferably, it is 25-90 mass%, More preferably, 30-85 mass%, More preferably, it is 35-80 mass%.

<Aspect of Production Method II>
Although there is no restriction | limiting in particular in the 2nd manufacturing method, From a viewpoint of productivity and the viewpoint of making it easy to form a recessed part and a flat surface in the surface ((alpha)) of a resin layer, the following II-1 aspect and II- The manufacturing method of 2 aspects is preferable.
In the description of the production methods of the following embodiments II-1 and II-2, “composition (xβ)” and “composition (xα)” are the first production method unless otherwise specified. Each of the components (resin, cross-linking agent, tackifier, general-purpose additive, dilution) included in the composition (xβ) or (xα) Details of the solvent and the like (specific illustration of each component, suitable component, content of the component, solid content concentration, and the like) are also the same as the above-described composition (xβ) or (xα).

<The manufacturing method of II-1 aspect>
The production method of the II-1 embodiment has at least the following steps (1A) and (2A).
Step (1A): A coating film (xβ ′) composed of the composition (xβ), a coating film (y1 ′) composed of the composition (y1), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating film (xα ′) in this order Step (2A): Simultaneously forming the coating film (xβ ′), coating film (y1 ′), and coating film (xα ′) formed in step (1A) Step of drying to form layer (Xβ), layer (Y1), and layer (Xα)

<Process (1A)>
Step (1A) comprises a coating film (xβ ′) composed of the composition (xβ), a coating film (y1 ′) composed of the composition (y1), and a composition (xα) on the base material or the release material. In this step, the coating film (xα ′) is formed by laminating in this order.
Also in the step (1A), it is preferable that the composition (xβ), the composition (y1), and the composition (xα) are mixed with the above-described solvent to form a solution of the composition and then applied. .
As a method for forming the coating film (xβ ′), the coating film (y1 ′), and the coating film (xα ′), after forming the coating film (xβ ′) on the substrate or the release material, the coating film (xβ It may be a method of sequentially forming using the above coater, such as ') forming a coating film (y1') and further forming a coating film (xα ') on the coating film (y1'). From the viewpoint of productivity, a method of forming the coating film (xβ ′), the coating film (y1 ′) and the coating film (xα ′) by simultaneous application using the multilayer coater described above may be used.

The coating amount of the coating film (xα ′) is preferably 1.5 to 800 g / m ² , more preferably 5 to 500 g / m ² , and still more preferably 10 to 300 g, from the viewpoint of improving air bleeding and adhesive properties. / M ² , more preferably 20 to 200 g / m ² .
The coating amount of the coating film (y1 ′) is preferably 1.5 to 800 g / m ² , more preferably 5 to 500 g / m ² , and still more preferably 10 to 300 g, from the viewpoint of improving air bleeding and adhesive properties. / M ² , more preferably 20 to 200 g / m ² .
The ratio [(xα ′) / (y1 ′)] of the coating amount between the coating film (xα ′) and the coating film (y1 ′) is preferably 100/5 to 5 from the viewpoint of improving the air release property and the adhesive property. 100/2000, More preferably, it is 100 / 50-100 / 1500, More preferably, it is 100 / 100-100 / 1000.

In Step (1A), after forming one or more coating films (xβ ′), coating film (y1 ′), and coating film (xα ′), before moving to Step (2A), You may perform the predrying process of the grade which does not advance the hardening reaction of a coating film.
The conditions for the pre-drying treatment in this step (1A) are the same as those in step (1a) in the first manufacturing method described above.

<Process (2A)>
In the step (2A), the coating film (xβ ′), the coating film (y1 ′), and the coating film (xα ′) formed in the step (1A) are simultaneously dried, and the layer (Xβ), the layer (Y1), and This is a step of forming the layer (Xα).
The suitable range of the drying temperature in the step (2A) is the same as that in the above-described step (1A). By this step (2A), a resin layer including the resin portion (X) and the particle portion (Y) is formed.
In addition, the step (2A) effectively forms an irregular recess on the surface (α) of the layer (Xα), and the irregular recess is formed, so that the flat surface has an irregular shape. Become.
The void portion (Z) can be easily formed by using at least one selected from silica particles, metal oxide particles, and smectite as the fine particles contained in the composition (y).

<The manufacturing method of II-2 aspect>
The production method of the II-2 embodiment has at least the following steps (1B) and (2B).
Step (1B): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y1 ′) composed of the composition (y1), and the composition (xα Step (2B): The coating film (y1 ′) and the coating film (xα ′) formed in the step (1B) are simultaneously dried to form a layer. Step of forming (Y1) and layer (Xα)

<Process (1B)>
In the step (1B), on the surface of the substrate or the release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y1 ′) composed of the composition (y1), and the composition (xα ) Is formed by laminating a coating film (xα ′) consisting of
In the step (1B), the “layer (Xβ) mainly including the resin portion (X)” is formed by drying the coating film (xβ ′) made of the composition (xβ) including the resin as the main component. be able to.
Since the layer (Xβ) is formed from the composition (xβ), the layer (Xβ) may contain a crosslinking agent, a general-purpose additive and the like in addition to the resin. The content of the resin portion (X) in the layer (Xβ) is as described above.

As a method for forming the layer (Xβ), a coating film (xβ ′) made of a composition (xβ) containing a resin is formed on a base material or a release material, and the coating film (xβ ′) is dried. can do.
There is no restriction | limiting in particular as drying temperature at this time, Preferably it is 35-200 degreeC, More preferably, it is 60-180 degreeC, More preferably, it is 70-160 degreeC, More preferably, it is 80-140 degreeC.

In this embodiment, the coating film (y1 ′) and the coating film (xα ′) are formed in this order on the layer (Xβ) obtained after drying, not on the coating film (xβ ′). This is different from the above-mentioned embodiment II-1.
Also in the step (1B), it is preferable that the composition (y1) and the composition (xα) are mixed with the above-described solvent to form a solution of the composition and then applied.
As a method of forming the coating film (y1 ′) and the coating film (xα ′), after forming the coating film (y1 ′) on the layer (Xβ), the coating film (xα ′) is formed on the coating film (y1 ′). ) May be sequentially formed using the above-mentioned coater, or the coating (y1 ′) and the coating (xα ′) may be simultaneously applied and formed using the above-mentioned multilayer coater. Good.

The coating amount of the coating film (xα ′), the coating amount of the coating film (y1 ′), and the ratio of the coating amount of the coating film (xα ′) to the coating film (y1 ′) [(xα ′) / (y1 ′) ] Is the same as the above-mentioned step (1A).
In this step (1B), after the formation of the coating film (y1 ′) or after the formation of the coating film (y1 ′) and the coating film (xα ′), before moving to the step (2B), the coating film You may perform the predrying process of the grade which does not advance hardening reaction.
The conditions for the pre-drying treatment in this step (1B) are the same as those in the above-described step (1A).

<Process (2B)>
The step (2B) is a step of simultaneously drying the coating film (y1 ′) and the coating film (xα ′) formed in the step (1B) to form the layer (Y1) and the layer (Xα).
The suitable range of the drying temperature in the step (2B) is the same as that in the above step (1B).
By this step, a resin layer including the resin portion (X) and the particle portion (Y) is formed.
In addition, by the step (2B), an irregular recess is effectively formed on the surface (α) of the layer (Xα), and the irregular recess is formed, so that the flat surface has an irregular shape. Become.

[Adhesive sheet]
In the present invention, the following first adhesive sheet is obtained by the first manufacturing method, and the following second adhesive sheet is obtained by the second manufacturing method.
<First adhesive sheet>
The first pressure-sensitive adhesive sheet has a resin layer obtained by laminating a layer (Xβ), a layer (Y1), and a layer (Xα) in this order on a base material or a release material, and at least the layer (Xα) The surface (α) is an adhesive sheet having adhesiveness,
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed from a composition (y) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier,
A layer (X (alpha)) is an adhesive sheet which is a layer formed from the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.

<Second adhesive sheet>
The second pressure-sensitive adhesive sheet has a resin layer obtained by laminating the layer (Xβ), the layer (Y1), and the layer (Xα) in this order on the base material or the release material, and at least the layer (Xα) The surface (α) is an adhesive sheet having adhesiveness,
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed of a composition (y1) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier and containing 15% by mass or more of fine particles,
A layer (X (alpha)) is an adhesive sheet which is a layer formed from the composition (x (alpha)) containing 100 mass parts of adhesive resins and 1 mass part or more of tackifiers.
The configuration of the pressure-sensitive adhesive sheet of the present invention is as described above.
The pressure-sensitive adhesive sheet of the present invention has an irregular recess on the surface (α) of the layer (Xα).
The recess is formed by self-forming the resin layer.
Moreover, in the adhesive sheet of this invention, it is preferable that a composition (x (beta)) does not contain a tackifier substantially.

  The present invention will be specifically described with reference to the following examples, but the present invention is not limited to the following examples. In addition, the physical-property value in the following manufacture examples and Examples is a value measured by the following method.

<Mass average molecular weight of resin (Mw)>
Using a gel permeation chromatograph device (product name “HLC-8020” manufactured by Tosoh Corporation), the value measured under the following conditions and measured in terms of standard polystyrene was used.
(Measurement condition)
Column: “TSK guard column HXL-L”, “TSK gel G2500HXL”, “TSK gel G2000HXL”, “TSK gel G1000HXL” (both manufactured by Tosoh Corporation), column temperature: 40 ° C.
・ Developing solvent: Tetrahydrofuran ・ Flow rate: 1.0 mL / min

<Measurement of volume average secondary particle diameter of silica particles>
The volume average secondary particle diameter of the silica particles was determined by measuring the particle size distribution by a Coulter counter method using a multisizer three machine (manufactured by Beckman Coulter, Inc.).

<Measurement of resin layer thickness>
It was measured using a constant pressure thickness measuring instrument (model number: “PG-02J”, standard: conforming to JIS K6783, Z1702, Z1709) manufactured by Teclock Co., Ltd.
Specifically, after measuring the total thickness of the pressure-sensitive adhesive sheet to be measured, a value obtained by subtracting the thickness of the base material or release sheet measured in advance was defined as “the thickness of the resin layer”.

Production Examples x-1 to x-3
(Preparation of resin composition solutions (xβ-1) and (xα-1) to (xα-2))
To the solution of the acrylic resin of the type and solid content described in Table 1, the crosslinking agent and tackifier of the type and blending amount described in Table 1 are added, and the dilution solvent described in Table 1 is used. It diluted and prepared the solution (x (beta) -1) and (x (alpha) -1)-(x (alpha) -2) of the resin composition which has solid content concentration of Table 1, respectively.

In addition, the detail of each component of Table 1 used for preparation of the resin composition solution (xβ-1) and (xα-1) to (xα-2) is as follows.
<Acrylic resin solution>
Solution (i): Contains acrylic resin (xi) (acrylic copolymer having a structural unit derived from a raw material monomer consisting of BA / AA = 90/10 (mass%), Mw: 470,000) A mixed solution of toluene and ethyl acetate having a solid content concentration of 37.0% by mass.
-Solution (ii): Acrylic resin (x-ii) (2EHA / VAc / AA = acrylic copolymer having a structural unit derived from a raw material monomer consisting of 75/23/2 (mass%), Mw: 66 A mixed solution of toluene and ethyl acetate having a solid content concentration of 33.0% by mass.
-Solution (iii): Acrylic resin (x-iii) (2EHA / BA / Vac / AA = 70/20/5/5 (mass%) acrylic copolymer having a structural unit derived from a raw material monomer , Mw: 630,000), and a mixed solution of toluene and ethyl acetate having a solid concentration of 33.5% by mass.
In addition, the abbreviation of the raw material monomer which said acrylic copolymer comprises is as follows.
BA: n-butyl acrylate 2EHA: 2-ethylhexyl acrylate AA: acrylic acid VAc: vinyl acetate

<Crosslinking agent>
Al-based crosslinking agent: Product name “M-5A”, manufactured by Soken Chemical Co., Ltd., aluminum chelate-based crosslinking agent, solid content concentration = 4.95% by mass.
Epoxy-based crosslinking agent: A solution of an epoxy-based crosslinking agent obtained by diluting “TETRAD-C” (product name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) with toluene to a solid content concentration of 5 mass%.

<Tackifier>
-Rosin ester type TF: Rosin ester type polymer, Mw: less than 10,000, softening point: 135 ° C.
Terpene TF: aromatic modified terpene polymer, Mw: less than 10,000, softening point: 115 ° C.
-Hydrogenated terpene series TF: Hydrogenated product of aromatic modified terpene series polymer, Mw: less than 10,000, softening point: 100 ° C.

<Diluted solvent>
-Mixed solvent (1): Mixed solvent formed by mixing with toluene / isopropyl alcohol (IPA) = 35/65 (mass ratio).
-Mixed solvent (2): Mixed solvent formed by mixing with toluene / IPA = 40/60 (mass ratio).

Production Example f-1
(Preparation of fine particle dispersion (f-1))
Acrylic copolymer (Mw: 470,000) having a structural unit derived from a raw material monomer comprising the above-mentioned acrylic resin (xi) (i) (BA / AA = 90/10 (mass%)) A mixed solution of toluene and ethyl acetate having a solid content concentration of 37.0% by mass.
Silica particles (product name “Nip Seal E-200A”, manufactured by Tosoh Silica Co., Ltd., volume average secondary particle diameter) are used as fine particles with respect to 100 parts by mass (solid content: 37.0 parts by mass) of the solution (i). : 3 μm) is added to 55.5 parts by mass (solid content: 55.5 parts by mass) and toluene to disperse the fine particles, and the solid content concentration containing acrylic resin (xi) and silica particles is 30 masses. % Fine particle dispersion (f-1) was prepared.

Production Examples y-1 to y-4
(Preparation of coating solutions (y-1) to (y-4) for forming a coating film (y ′))
Addition of fine particle dispersion, acrylic resin solution, cross-linking agent, tackifier and diluent solvent described in Table 2 to form solid coating film (y ′) as shown in Table 2 Coating solutions (y-1) to (y-4) were prepared.

In addition, the detail of each component of Table 2 used for preparation of the coating liquid (y-1)-(y-4) for coating-film (y ') formation is as follows.
<Fine particle dispersion>
-Dispersion (f-1): A fine particle dispersion (f-1) prepared in Production Example f-1 and containing an acrylic resin (xi) and silica particles at a solid content concentration of 30% by mass.
<Acrylic resin solution>
Solution (i): Acrylic resin (xi) (acrylic copolymer having a structural unit derived from a raw material monomer consisting of BA / AA = 90/10 (mass%), Mw: 470,000) A mixed solution of toluene and ethyl acetate having a solid content concentration of 37.0% by mass.
<Crosslinking agent>
Al-based crosslinking agent: Product name “M-5A”, manufactured by Soken Chemical Co., Ltd., aluminum chelate-based crosslinking agent, solid content concentration = 4.95% by mass.
<Tackifier>
-Rosin ester type TF: Rosin ester type polymer, Mw: less than 10,000, softening point: 135 ° C.
Terpene TF: aromatic modified terpene polymer, Mw: less than 10,000, softening point: 115 ° C.
-Hydrogenated terpene series TF: Hydrogenated product of aromatic modified terpene series polymer, Mw: less than 10,000, softening point: 100 ° C.
<Diluted solvent>
-Mixed solvent (3): IPA / CHN: Mixed solvent consisting of isopropyl alcohol (IPA) and cyclohexanone (CHN) (IPA / CHN = 95/5 (mass ratio)).

Examples 1-3, Comparative Example 1
(1) Formation of coating film A polyethylene terephthalate (PET) film (produced by Lintec Corporation, product name “FNS Poppy N50”, thickness 50 μm) provided with an aluminum vapor deposition layer on one side was used as a base material.
On the aluminum vapor deposition layer of the said PET film, the solution (x (beta) -1) of the resin composition prepared by manufacture example x-1 was apply | coated by the application quantity shown in Table 3 using an applicator, and a coating film (x (beta)). ') Formed.
Next, on the formed coating film (xβ ′), using an applicator, any of coating liquids (y-1) to (y-4) for forming a coating film (y ′) shown in Table 3 is used. The coating was applied at the coating amount shown in Table 3 to form a coating film (y ′).
Then, on the formed coating film (y ′), the resin composition solution (xα-1) prepared in Production Example x-2 was applied at an application amount shown in Table 3 using an applicator. A film (xα ′) was formed.

(2) Drying treatment Then, the formed three-layer coating film (xβ ′), coating film (y ′), and coating film (xα ′) were simultaneously dried at a drying temperature of 100 ° C. for 2 minutes to obtain a resin portion. A resin layer having a thickness shown in Table 3 including (X) and a particle portion (Y) was formed.
And it laminates on the surface ((alpha)) of the formed resin layer so that it may bond with the peeling process surface of the peeling film (the product name "SP-PET381031" by Lintec Co., Ltd.) which is a peeling material, and adhesion with a base material A sheet was produced.

Example 4
On the aluminum vapor deposition layer of the PET film same as that used in Example 1, the resin composition solution (xβ-1) prepared in Production Example x-1 and the coating film prepared in Production Example y-4 ( y ′) The coating solution for formation (y-4) and the solution (xα-1) of the resin composition prepared in Production Example x-2 were applied in this order using a multilayer die coater (width: 250 mm). Coating was simultaneously performed at a speed of 6 m / min, and coating films (xβ ′), coating films (y ′), and coating films (xα ′) having coating amounts shown in Table 3 were simultaneously formed.
Then, operation similar to Example 1 was performed, the resin layer of the thickness shown in Table 3 was formed, and the adhesive sheet with a base material was produced.

Comparative Example 2
On the same aluminum vapor deposition layer of PET film as used in Example 1, the resin composition solution (xβ-1) prepared in Production Example x-1 and the coating film prepared in Production Example y-1 ( y ′) The coating solution for formation (y-1) and the solution (xα-2) of the resin composition prepared in Production Example x-3 were used in this order using a multilayer die coater (width: 250 mm). Coating was simultaneously performed at a coating speed of 6 m / min, and coating films (xβ ′), coating films (y ′), and coating films (xα ′) having coating amounts shown in Table 3 were formed simultaneously.
Then, operation similar to Example 1 was performed, the resin layer of the thickness shown in Table 3 was formed, and the adhesive sheet with a base material was produced.

  Using the pressure-sensitive adhesive sheet with a substrate prepared in Examples and Comparative Examples, the characteristics of the resin layer and the pressure-sensitive adhesive sheet included in the pressure-sensitive adhesive sheet were measured or observed by the following method. These results are shown in Table 4.

<State of resin layer surface (α)>
(1) Presence or absence of irregular recesses
On the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Examples and Comparative Examples, four regions (D) surrounded by a rectangle of 8 mm in length and 10 mm in width are arbitrarily selected, and the inside of each region (D) is selected. A digital microscope (manufactured by Keyence Corporation, product name “Digital Microscope VHX-1000”, magnification: 50 ×) was observed and photographed from the surface (α) side in a plan view (stereoscopic view if necessary).
In this case, more specifically, the focal point is moved in order from the upper part of the part visually determined to be a flat surface from the direction A in FIG. 5, and the first focused part is photographed as a flat surface. . Furthermore, using a digital microscope (50 times magnification), a connected image obtained by connecting arbitrarily selected ranges on the surface (α) to each other by the image connecting function of the digital microscope is obtained, and in the obtained connected image A region surrounded by a rectangle of 8 mm in length × 10 mm in width was arbitrarily selected, and this was designated as “image of region (D)”.
In addition, when it is not possible to determine whether the surface is flat or not by visual inspection of the image, a squeegee is applied so as not to apply a load to the translucent adherend having a smooth surface on the surface (α) of the resin layer as much as possible. 5 and taken from the direction A in FIG. 5 to photograph the interface between the smooth surface of the translucent adherend and the surface (α) 12a of the resin layer 12, and determined that the pasted portion is a flat surface. did. As the translucent adherent having a smooth surface, non-alkali glass (product name “Eagle XG”, manufactured by Corning Inc.) was used.
The image of the obtained area | region (D) was observed, the presence or absence of the amorphous recess was confirmed, and the presence or absence of the amorphous recess on the surface (α) was evaluated according to the following criteria.
A: In any selected region (D), an irregular recess was confirmed.
B: In a part of the selected region (D), an irregular recess was confirmed.
C: In any of the selected regions (D), the presence of a recess could not be confirmed.

(2) Area ratio of flat surface
Based on the “image of region (D)” obtained in (1) above, automatic area measurement was performed using the same digital microscope as above, and the area of each flat surface existing in region (D) was obtained. .
In the automatic area measurement, the flat surface existing in the region (D) is binarized by a digital microscope and, if necessary, visual image processing, and then the numerical value (area) of the obtained binarized image is obtained. Measurement was performed to measure the area of each flat surface. When there were a plurality of flat surfaces, the area of each flat surface was measured. The “area ratio (%) occupied by the flat surface”, which is the ratio of the total area of the obtained flat surfaces to the total area of the region (D), was calculated.
The conditions for automatic area measurement are as follows.
(Automatic area measurement conditions)
-Extraction mode: Luminance (weak noise removal)
And extracting region: numerical specification extracting a rectangular longitudinal 8 mm × horizontal 10mm at (rectangle) and extraction regions shaping of: Grain removal (area 100 [mu] m ² or less removed)

<Air escape characteristics>
A pressure-sensitive adhesive sheet with a base material having a size of 50 mm long × 50 mm wide was affixed to a melamine coating plate as an adherend so that air retention occurred. And the presence or absence of the air pocket after crimping | compression-bonding using a squeegee was observed, and the air release property of each adhesive sheet was evaluated with the following references | standards.
A: The air pocket has disappeared, and the air release property is excellent.
F: An air pocket remains and the air release property is inferior.

<Adhesive properties>
(1) Adhesive strength 7 days after production The adhesive sheets with base materials produced in Examples and Comparative Examples were allowed to stand for 7 days in an environment of 23 ° C. and 50% RH (relative humidity), and the size was 25 mm long × 300 mm wide. Then, the surface (α) of the resin layer of the pressure-sensitive adhesive sheet is attached to a stainless steel plate (SUS304, No. 360 polishing) under the same environment to prepare a sample for measuring adhesive strength. Let stand for hours.
After standing, the adhesive strength of each pressure-sensitive adhesive sheet was measured at a pulling speed of 300 mm / min by a 180 ° peeling method based on JIS Z0237: 2000, and the adhesive strength was defined as “adhesive strength after 7 days from preparation”.
(2) Adhesive strength 30 days after production The adhesive sheets with base materials produced in Examples and Comparative Examples were allowed to stand for 30 days in an environment of 23 ° C. and 50% RH (relative humidity), and had a size of 25 mm length × 300 mm width. Then, the surface (α) of the resin layer of the pressure-sensitive adhesive sheet is attached to a stainless steel plate (SUS304, No. 360 polishing) under the same environment to prepare a sample for measuring adhesive strength. Let stand for hours.
After standing, the adhesive strength of each adhesive sheet was measured at a pulling speed of 300 mm / min by a 180 ° peeling method based on JIS Z0237: 2000, and the adhesive strength was defined as “adhesive strength after 30 days of production”.
(3) Adhesive strength change rate From the measured values of "Adhesive strength after 7 days of production" and "Adhesive strength after 30 days of production", the adhesive strength change rate was calculated from the following formula. It can be said that the larger the value is, the better the adhesive property is, and the lowering of the adhesive strength over time is suppressed.
[Adhesive strength change rate] (%) = ([Adhesive strength after 30 days of preparation] − [Adhesive strength after 7 days of preparation]) / [Adhesive strength after 7 days of preparation] × 100
(4) Presence of cloudiness When the adhesive force was measured 30 days after the production described above, the adherend after the adhesive sheet was removed from the adherend (SUS) was visually observed, and the presence or absence of cloudiness was observed according to the following criteria. evaluated.
A: Cloudiness is not seen in the adherend (SUS) after removing the adhesive sheet.
F: Cloudiness is seen in the part where the adhesive sheet of the adherend (SUS) was pasted.

The pressure-sensitive adhesive sheets obtained in Examples 1 to 4 have better pressure-sensitive adhesive properties than the pressure-sensitive adhesive sheets obtained in Comparative Examples 1 and 2, and a decrease in the adhesive strength over time is suppressed. It can be seen that the phenomenon that the adherend is clouded can be suppressed.
6 and 7 are each surrounded by a rectangle of 8 mm in length and 10 mm in width selected on the surface (α) of the resin layer of the adhesive sheet prepared in Example 4 and Comparative Example 2, respectively. This is a binarized image of an image obtained by photographing the region (D) from the surface (α) side using a digital microscope. That is, the vertical image of FIG. 6 and FIG. 7 corresponds to “8 mm” in the vertical direction and “10 mm” in the horizontal direction.
In these binarized images, the black portion is a flat surface and the white portion corresponds to a concave portion, but in FIG. 6 of Example 4, a finer flat surface and a concave portion are compared with FIG. 7 of Comparative Example 2. Therefore, it is considered that the adhesive property is good, the decrease in the adhesive strength with time is suppressed, and the phenomenon that the adherend becomes cloudy can be suppressed when reattaching.

  The pressure-sensitive adhesive sheet of one embodiment of the present invention is useful as a pressure-sensitive adhesive sheet having a large pasting area, which is used for identification or decoration, for coating masking, for protecting a surface of a metal plate or the like.

1a, 11a, 12a, 1b, 2a, 2b Adhesive sheet 11 Base material 12 Resin layer 12a Surface (α)
12b Surface (β)
(X) Resin part (X)
(Y) Particle part (Y)
(Xβ) Layer (Xβ) mainly containing resin part (X)
(Xα) Layer mainly containing resin portion (X) (Xα)
(Y1) Layer (Y1) containing 15% by mass or more of the particle part (Y)
13, 13a, 131, 132 Concave part 14 Flat surface 14a Flat part 15a Convex part 21, 22 Release material 50 Square 51, 52 Diagonal line 60 Cross section (P1)
61, 62 cross section

Claims (25)

It has a resin layer formed by laminating the layer (Xβ), the layer (Y1), and the layer (Xα) in this order on the base material or release material, and at least the surface (α) of the layer (Xα) is adhesive. A method for producing a pressure-sensitive adhesive sheet having
The layer (Xβ) is formed using a composition (xβ) containing a resin,
The layer (Y1) is formed using a composition (y) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier,
The layer (Xα) is formed using a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier.
A method for producing an adhesive sheet. The manufacturing method of the adhesive sheet of Claim 1 which has following process (1a) and (2a) at least.
Step (1a): A coating film (xβ ′) composed of the composition (xβ), a coating film (y ′) composed of the composition (y), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating and forming a film (xα ′) in this order Step (2a): The coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1a) are simultaneously formed. Step of drying to form layer (Xβ), layer (Y1), and layer (Xα) The manufacturing method of the adhesive sheet of Claim 1 which has the following process (1b) and (2b) at least.
Step (1b): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y ′) comprising the composition (y), and the composition (xα Step (2b): The coating film (y ′) and the coating film (xα ′) formed in the step (1b) are simultaneously dried to form a layer. Step of forming (Y1) and layer (Xα) It has a resin layer formed by laminating the layer (Xβ), the layer (Y1), and the layer (Xα) in this order on the base material or release material, and at least the surface (α) of the layer (Xα) is adhesive. A method for producing a pressure-sensitive adhesive sheet having
The layer (Xβ) is formed using a composition (xβ) containing a resin,
The layer (Y1) is formed using a composition (y1) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier, and containing 15% by mass or more of fine particles,
The layer (Xα) is formed using a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier.
A method for producing an adhesive sheet. The manufacturing method of the adhesive sheet of Claim 4 which has following process (1A) and (2A) at least.
Step (1A): A coating film (xβ ′) composed of the composition (xβ), a coating film (y1 ′) composed of the composition (y1), and a coating composed of the composition (xα) on the substrate or the release material. Step of laminating film (xα ′) in this order Step (2A): Simultaneously forming the coating film (xβ ′), coating film (y1 ′), and coating film (xα ′) formed in step (1A) Step of drying to form layer (Xβ), layer (Y1), and layer (Xα) The manufacturing method of the adhesive sheet of Claim 4 which has the following process (1B) and (2B) at least.
Step (1B): On the surface of the substrate or release material, on the layer (Xβ) formed from the composition (xβ), the coating film (y1 ′) composed of the composition (y1), and the composition (xα Step (2B): The coating film (y1 ′) and the coating film (xα ′) formed in the step (1B) are simultaneously dried to form a layer. Step of forming (Y1) and layer (Xα)   The method for producing an adhesive sheet according to claim 5 or 6, wherein an irregular recess is formed on the surface (α) of the layer (Xα) by the step (2A) or (2B).   The content of the tackifier contained in the composition (xα) is 400 parts by mass or less with respect to 100 parts by mass of the adhesive resin in the composition (xα). The manufacturing method of the adhesive sheet of description.   The content of the tackifier contained in the composition (y) or the composition (y1) is 400 parts by mass or less with respect to 100 parts by mass of the resin in the composition (y) or the composition (y1). The manufacturing method of the adhesive sheet of any one of Claims 1-8.   The method for producing a pressure-sensitive adhesive sheet according to any one of claims 1 to 9, wherein the composition (xβ) contains substantially no tackifier.   Content ratio [(xα) / (y)] or [(xα) / of the tackifier contained in the composition (xα) and the tackifier contained in the composition (y) or the composition (y1) (Y1)] is a mass ratio and is 100 / 500-100 / 10, The manufacturing method of the adhesive sheet of any one of Claims 1-10. The manufacturing method of the adhesive sheet of any one of Claims 1-11 whose application quantity of a coating film (x (alpha) ') is 1.5-800 g / m < ² >. The manufacturing method of the adhesive sheet of any one of Claims 1-12 whose coating amount of a coating film (y ') or a coating film (y1') is 1.5-800 g / m < ² >.   Ratio of coating amount of coating film (xα ′) to coating film (y ′) or coating film (y1 ′) [(xα ′) / (y ′)] or [(xα ′) / (y1 ′)] Is the manufacturing method of the adhesive sheet of any one of Claims 1-13 which are 100/5-100/2000.   The manufacturing method of the adhesive sheet of any one of Claims 1-14 whose content of the tackifier with respect to the total mass of 100 mass% of the said resin layer is 2-60 mass%.   The method for producing an adhesive sheet according to any one of claims 1 to 15, wherein the resin contained in the composition (xβ) and the composition (y) or the composition (y1) is an adhesive resin.   The method for producing an adhesive sheet according to any one of claims 1 to 16, wherein the adhesive resin contained in the composition (xα) is an acrylic resin having a functional group.   The method for producing a pressure-sensitive adhesive sheet according to claim 17, wherein the composition (xα) further contains one or more selected from a metal chelate-based crosslinking agent, an epoxy-based crosslinking agent, and an aziridine-based crosslinking agent.   The method for producing a pressure-sensitive adhesive sheet according to claim 17 or 18, wherein the functional group is a carboxy group.   The method for producing a pressure-sensitive adhesive sheet according to any one of claims 4 to 19, wherein the fine particles contained in the composition (y) are at least one selected from silica particles, metal oxide particles, and smectites. It has a resin layer formed by laminating the layer (Xβ), the layer (Y1), and the layer (Xα) in this order on the base material or release material, and at least the surface (α) of the layer (Xα) is adhesive. An adhesive sheet having
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed from a composition (y) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier,
The layer (Xα) is a layer formed from a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier,
Adhesive sheet. It has a resin layer formed by laminating the layer (Xβ), the layer (Y1), and the layer (Xα) in this order on the base material or release material, and at least the surface (α) of the layer (Xα) is adhesive. An adhesive sheet having
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin,
The layer (Y1) is a layer formed of a composition (y1) containing 100 parts by mass of a resin and 1 part by mass or more of a tackifier and containing 15% by mass or more of fine particles,
The layer (Xα) is a layer formed from a composition (xα) containing 100 parts by mass of an adhesive resin and 1 part by mass or more of a tackifier,
Adhesive sheet.   The pressure-sensitive adhesive sheet according to claim 22, wherein the pressure-sensitive adhesive sheet has an irregular recess on the surface (α) of the layer (Xα).   The pressure-sensitive adhesive sheet according to claim 23, wherein the concave portion is formed by self-forming of the resin layer.   The pressure-sensitive adhesive sheet according to any one of claims 21 to 24, wherein the composition (xβ) contains substantially no tackifier.