WO2015152348A1

WO2015152348A1 - Adhesive sheet

Info

Publication number: WO2015152348A1
Application number: PCT/JP2015/060414
Authority: WO
Inventors: 慈齋藤; 道生金井; 揮一郎加藤; 和恵上村; 由美子網野
Original assignee: リンテック株式会社
Priority date: 2014-04-02
Filing date: 2015-04-02
Publication date: 2015-10-08
Also published as: JPWO2015152348A1; JP6520924B2; TWI667316B; TW201602293A

Abstract

Provided is an adhesive sheet: having a resin layer including a resin section (X) including resin as the main component thereof and a particle section (Y) comprising microparticles, upon a base material or a releasing material; and wherein at least a surface (α) of the resin layer on the opposite side to the side on which the base material or the releasing material is provided is sticky. A plurality of recessed sections having a maximum height difference of at least 1.5 µm are present within a prescribed area (P) upon the surface (α). At least 95% of the plurality of recessed sections present inside said area (P) have mutually different shapes and the area ratio occupied by the recessed sections in the surface (α) is 16%-95%. The adhesive sheet has excellent air-escaping properties whereby air pockets that can occur when the adhesive sheet is pasted to an adherend can be easily removed and also has good blister resistance and good adhesion characteristics.

Description

Adhesive sheet

The present invention relates to 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 stuck to the adherend and attached.
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.

JP 2001-507732 A

However, the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer in which grooves having a specific shape are arranged in a predetermined pattern, as described in Patent Document 1 or the like, is difficult to remove air when the groove width is narrow, and the groove width is wide. There is a problem that not only the surface substrate is recessed and the appearance is inferior, but also the adhesive strength is lowered.
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 occur 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.
In addition, since the pressure-sensitive adhesive sheet described in Patent Document 1 is inferior in blister resistance, there is a problem that blisters are likely to occur when used at high temperatures.

The present invention provides a pressure-sensitive adhesive sheet that has excellent air bleedability that can easily remove air pockets that may occur when affixed to an adherend, and that also has excellent blister resistance and adhesive properties. The purpose is to do.

The present inventor has a resin layer including a resin portion containing a resin as a main component and a particle portion composed of fine particles, and within an arbitrarily selected predetermined region on the adhesive surface of the resin layer. In addition, a pressure-sensitive adhesive sheet having a height difference of 1.5 μm or more and having a plurality of recesses having different shapes from each other at a predetermined ratio, and an area ratio occupied by the recesses within a specific range, The inventors have found that this can be solved and completed the present invention.

That is, the present invention provides the following [1] to [19].
[1] A resin layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or the release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
A plurality of concave portions having a height difference of 1.5 μm or more exist in the region (P) surrounded by a square with a side of 5 mm arbitrarily selected on the surface (α), and exist in the region (P). In the pressure-sensitive adhesive sheet, 95% or more of the plurality of recesses have shapes different from each other, and the area ratio of the recesses on the surface (α) is 16 to 95%.
[2] The pressure-sensitive adhesive sheet according to [1], wherein the plurality of recesses are irregularly present on the surface (α).
[3] The pressure-sensitive adhesive sheet according to the above [1] or [2], wherein the shape of the pasting surface on the surface (α) of the resin layer is indefinite.
[4] The pressure-sensitive adhesive sheet according to any one of the above [1] to [3], wherein the resin contained in the resin portion (X) includes a pressure-sensitive adhesive resin.
[5] The pressure-sensitive adhesive sheet according to any one of the above [1] to [4], wherein the resin contained in the resin portion (X) contains a resin having a functional group.
[6] The pressure-sensitive adhesive sheet according to [5], wherein the resin having a functional group is an acrylic resin having a functional group.
[7] The pressure-sensitive adhesive sheet according to the above [5] or [6], wherein the functional group is a carboxy group.
[8] In any one of the above [5] to [7], the resin part (X) further contains one or more selected from a metal chelate crosslinking agent, an epoxy crosslinking agent, and an aziridine crosslinking agent. The adhesive sheet as described.
[9] The pressure-sensitive adhesive sheet according to any one of the above [5] to [8], wherein the resin part (X) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent.
[10] The pressure-sensitive adhesive sheet according to any one of [1] to [9], wherein the fine particles are one or more selected from silica particles, metal oxide particles, and smectites.
[11] The pressure-sensitive adhesive sheet according to any one of the above [1] to [10], wherein the surface (β) of the resin layer on the side on which the base material or release material is provided has adhesiveness.
[12] The pressure-sensitive adhesive sheet according to [11], wherein the resin layer is provided on the release material.
[13] The pressure-sensitive adhesive sheet according to any one of the above [1] to [12], wherein a mass retention after heating the resin layer at 800 ° C. for 30 minutes is 3 to 90% by mass.
[14] The pressure-sensitive adhesive sheet according to any one of [1] to [13], wherein the concave portion is not formed by transferring an emboss pattern.
[15] A layer (X1) mainly containing a resin part (X), a layer (Y1) containing 15% by mass or more of a particle part (Y) from the side on which the substrate or release material is provided, The pressure-sensitive adhesive sheet according to any one of the above [1] to [14], which has a multilayer structure in which a layer (Xα) mainly containing a resin portion (X) is laminated in this order.
[16] The layer (Xβ) is a layer formed from a composition (xβ) containing a resin as a main component,
The layer (Y1) is a layer formed from a composition (y) containing 15% by mass or more of fine particles,
The pressure-sensitive adhesive sheet according to the above [15], wherein the layer (Xα) is a layer formed from a composition (xα) containing a resin as a main component.
[17] A method for producing a pressure-sensitive adhesive sheet according to any one of the above [1] to [16], comprising at least the following steps (1) and (2).
Step (1): Forming a coating film (x ′) composed of a composition (x) containing a resin as a main component and a coating film (y ′) composed of a composition (y) containing 15% by mass or more of the fine particles. Step (2): A step of simultaneously drying the coating film (x ′) and the coating film (y ′) formed in the step (1) [18] A method for producing the pressure-sensitive adhesive sheet according to [16] above. The manufacturing method of the adhesive sheet which has following process (1A) and (2A) at least.
Step (1A): a coating film (xβ ′) made of a composition (xβ) containing a resin as a main component on a substrate or a release material, and a coating film made of a composition (y) containing 15% by mass or more of the fine particles. (Y ′) and a coating film (xα ′) made of a composition (xα) containing a resin as a main component is laminated and formed in this order. Step (2A): Coating film formed in step (1A) ( xβ ′), coating film (y ′), and coating film (xα ′) are simultaneously dried [19] A method for producing the pressure-sensitive adhesive sheet according to the above [16], comprising at least the following process (1B) and The manufacturing method of the adhesive sheet which has (2B).
Step (1B): a coating film comprising a composition (y) containing 15% by mass or more of the fine particles on a layer (Xβ) mainly containing a resin portion (X) provided on a substrate or a release material ( Step (2B): A coating film (y) formed by laminating and forming a coating film (xα ′) made of a composition (xα) containing a resin as a main component in this order (y ′) ') And the step of simultaneously drying the coating film (xα')

The pressure-sensitive adhesive sheet of the present invention has excellent air bleedability capable of easily removing air pockets that may be generated when it is attached to an adherend, and also has good blister resistance and pressure-sensitive adhesive properties.

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 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. (A) is a schematic plan view showing an example of the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention, and (b) is an arbitrarily selected length of 200 μm × width 283.6 μm on the surface (α). It is an image figure at the time of carrying out image processing (binarization process) of the image in the area | region (Q) of the rectangle 50 of. It is an image at the time of observing the adhesive sheet produced in Example 1 with the scanning electron microscope, (a) is a cross-sectional image of the said adhesive sheet, (b) is the surface ((alpha)) of the resin layer of the said adhesive sheet. It is a perspective image. It is an image at the time of observing the adhesive sheet produced in Example 10 with the scanning electron microscope, (a) is a cross-sectional image of the said adhesive sheet, (b) is the surface ((alpha)) of the resin layer of the said adhesive sheet. It is a perspective image. (A) is a three-dimensional image obtained by observing an arbitrarily selected region (Q) on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet produced in Example 1 using a laser microscope, b) was obtained by performing image processing (binarization processing) based on the three-dimensional image of (a) depending on whether or not it corresponds to a portion occupied by a recess having a height difference of 1.5 μm or more at the maximum. It is a binarized image of a region (Q). It is an image at the time of observing the adhesive sheet produced by the comparative example 1 with the scanning electron microscope, Comprising: (a) is a cross-sectional image of the said adhesive sheet, (b) is the surface ((alpha)) of the resin layer of the said adhesive sheet. It is a perspective image. (A) is a three-dimensional image obtained by observing an arbitrarily selected region (Q) on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Comparative Example 1 using a laser microscope, b) was obtained by performing image processing (binarization processing) based on the three-dimensional image of (a) depending on whether or not it corresponds to a portion occupied by a recess having a height difference of 1.5 μm or more at the maximum. It is a binarized image of a region (Q).

In the present invention, for example, “YY including XX component as main component” or “YY mainly composed of XX component” is described as “the component having the highest content among components included in YY is XX component. It means that there is. The specific content of the XX component in the description is usually 50% by mass or more, preferably 65 to 100% by mass, more preferably 75 to 100% by mass, based on the total amount of YY (100% by mass). Preferably, it is 85 to 100% by 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 obtain “10 to 60”. You can also.

[Configuration of adhesive sheet]
First, the structure of the adhesive sheet of this invention is demonstrated.
The pressure-sensitive adhesive sheet of the present invention has a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material.
FIG. 1 is a schematic cross-sectional view of an adhesive sheet showing an example of the structure of the adhesive sheet of the present invention.
As a specific configuration of the pressure-sensitive adhesive sheet of one embodiment of the present invention, for example, a pressure-sensitive adhesive sheet 1a having a resin layer 12 on a substrate 11 as shown in FIG. Such a pressure-sensitive adhesive sheet 1b having the resin layer 12 on the release material 14 is exemplified.

The pressure-sensitive adhesive sheet of the present invention has at least the surface (α) 12a (hereinafter, also simply referred to as “surface (α)”) of the resin layer 12 on the side opposite to the side on which the substrate 11 or the release material 14 is provided. Adhesive.
Therefore, as a pressure-sensitive adhesive sheet according to one embodiment of the present invention, a release material 14a is further provided on the surface (α) 12a of the resin layer 12 with respect to the pressure-sensitive adhesive sheet 1a or 1b shown in FIG. It is preferable to have a configuration such as the

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, the surface (β) 12b (hereinafter, also simply referred to as “surface (β)”) of the resin layer 12 on the side where the base material 11 or the release material 14 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.

The resin layer 12 included in the pressure-sensitive adhesive sheet of the present invention is a layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles, and on the surface (α) 12a of the resin layer 12 There is a recess 13.
When the particle part (Y) is contained in the resin layer, the occurrence of blisters can be effectively suppressed when the obtained pressure-sensitive adhesive sheet is used at a high temperature.
Moreover, the recessed part 13 which exists on the surface ((alpha)) is an air exhaust passage for releasing the "air pool" produced when sticking the surface ((alpha)) of the resin layer of the adhesive sheet of this invention to a to-be-adhered body. As a role.
In addition, the length of the concave portion 13 when the concave portion 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.

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).
As shown in FIGS. 1 (a) to 1 (d), in the resin layer 12 where the concave portion 13 exists on the surface (α), the proportion of the particle portion (Y) is larger than the others. The distribution may be reduced, or the particle portion (Y) may not be partially present.

The recess on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is formed, for example, by transferring an emboss pattern such as pressing a release material having an emboss pattern applied to the surface of the resin layer. This is different from a groove having a pre-designed shape.
The concave portion is preferably formed by self-forming the resin layer.
In the present invention, “self-forming” means a phenomenon that creates a disordered shape naturally in an autonomous formation process of a resin layer, and more specifically, formed from a composition that is a material for forming a 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.
That is, the recess formed by the self-formation of the resin layer is formed by a drying process of a coating film made of a composition that is a material for forming the resin layer.
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”.
Further, the concave portion is not formed at a predetermined position such as a groove formed by transferring the emboss pattern using a release material or the like to which the emboss pattern is applied.

The process of forming the recesses on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is considered as follows.
First, at the time of forming a coating film made of a composition containing fine particles as a material for forming the particle portion (Y), fine particles are present randomly in the coating film.
Here, in the step of drying the coating film, shrinkage stress is generated inside the coating film, and cracks are generated in the coating film at a portion where the binding force of the resin, which seems to be caused by the presence of fine particles, is weakened. 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.
In addition, in the drying process of the coating film, when cracks occur in the coating film, the fine particles that were originally present are pushed away to other parts, so the particle part (Y) where the recesses are formed occupies It is thought that the ratio will be less than others.

For example, the concave portion separately forms a coating film made of a composition having a high content of fine particles and a low content of resin and a coating film made of a composition containing a resin as a main component. It is easy to form by simultaneously drying the film.
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.
-Shape, type and mass concentration of fine particles.
-Composition of coating film forming material, dispersion state of fine particles in coating film, content of fine particles.
-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 fine particles and resin contained in the coating film to be formed.
For example, by adjusting the viscosity of a coating film made of a composition containing a large amount of fine particles to an appropriate range, while maintaining the predetermined fluidity of the fine particles in the coating film, other coating films (containing a large amount of resin) The mixing with the coating film) 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, by appropriately selecting fine particles, resin, etc. and optimizing the dispersion state of fine particles, the degree of swelling of the resin layer by fine particles and the self-forming ability of the recesses are 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 addition, it is preferable that the recessed part which exists on the surface ((alpha)) of the resin layer which the adhesive sheet of this invention has does not have a predetermined pattern. Here, the “predetermined pattern” means a shape that becomes a certain repeating unit of the concave portion when attention is paid to the shape of one concave portion.

In addition, from the viewpoint of forming a pressure-sensitive adhesive sheet with improved air release properties, the concave portions present on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention are visually observed from the surface (α) side of the exposed resin layer. Is preferably visible.

As shown in FIGS. 1 (a) to 1 (d), the pressure-sensitive adhesive sheet of the present invention has a surface (α) on the surface (α) of the resin layer 12 opposite to the side on which the substrate 11 or the release material 14 is provided. A plurality of recesses 13 are provided.
In the pressure-sensitive adhesive sheet of the present invention, the plurality of recesses 13 on the surface (α) satisfy the following requirements (I) to (III).
Requirement (I): A plurality of concave portions having a height difference of 1.5 μm or more at the maximum exist in a region (P) surrounded by a square of 5 mm on an arbitrarily selected surface on the surface (α).
Requirement (II): 95% or more of a plurality of recesses having a height difference of 1.5 μm or more present in a region (P) surrounded by a square of 5 mm on an arbitrarily selected surface on the surface (α) Have different shapes.
Requirement (III): The area ratio of the recesses having a height difference of 1.5 μm or more on the surface (α) is 16 to 95%.
Furthermore, the pressure-sensitive adhesive sheet of one embodiment of the present invention preferably satisfies at least one of the following requirements (IV) and (V), and satisfies both the following requirements (IV) and (V). More preferably.
Requirement (IV): On the surface (α), there are irregularly formed a plurality of concave portions having a height difference of at most 1.5 μm or more.
Requirement (V): The shape of the pasting surface on the surface (α) of the resin layer is indefinite.
Hereinafter, the requirements (I) to (V) will be described in detail.

<Requirement (I)>
FIG. 2 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. 2 (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 “height difference” of the recess means the highest position (m) of the two peak portions (M ₁ ) and (M ₂ ) in the thickness direction of the resin layer 12 (FIG. 2A). 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. 2A).
In the case of FIG. 2B, 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 height difference of the recess 131, and the maximum point of the peak portion (M ₁₃ ). And the length of the difference (h ₂ ) between the minimum point of the valley portion (N ₂ ) represents the height difference of the recess 132.

In the present invention, the “recess” present on the surface (α) refers to a recess having a height difference of 1.5 μm or more at the maximum. As the “concave portion” defined in the present invention, it is sufficient that a portion having a height difference of 1.5 μm or more exists in any part of the concave portion, and has the height difference over the entire region of the concave portion. There is no need.
In addition, whether or not there are a plurality of recesses that satisfy the requirement (I) is determined by selecting a region (P) on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet that is arbitrarily selected and surrounded by a 5 mm square. ) Is determined by observing the inside with an electron microscope. More specifically, it is determined by the method described in the examples.

The maximum value of the height difference of the one concave portion is preferably 2. from the viewpoint of improving the air release property of the pressure-sensitive adhesive sheet, maintaining the appearance of the pressure-sensitive adhesive sheet, and the shape stability of the pressure-sensitive adhesive sheet. The thickness is from 0 μm to the thickness of the resin layer, more preferably from 3.0 μm to the thickness of the resin layer, and even more preferably from 5.0 μm to the thickness of the resin layer.

The ratio between the maximum value of the height difference values of the plurality of recesses existing in the region (P) and the thickness of the resin layer [maximum value of height difference / thickness of the resin layer] is preferably 1 / 100 to 100/100, more preferably 5/100 to 99/100, still more preferably 10/100 to 96/100, still more preferably 15/100 to 90/100.

The average width of the recesses is preferably 1 to 500 μm, more preferably 3 to 400 μm, and more preferably 3 to 400 μm, from the viewpoint of improving the air release property of the pressure sensitive adhesive sheet and the pressure sensitive adhesive sheet. The thickness is preferably 5 to 300 μm.
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. 2A, 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. 2 (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.

Ratio of maximum value of height difference and average value of width of the single concave portion [maximum value of height difference / average value of width] (in the concave portion 13 shown in FIG. 2A, "h / L" Is preferably from 1/500 to 100/1, more preferably from 3/400 to 70/3, 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. More preferably, it is 1/60 to 10/1.

<Requirement (II)>
The pressure-sensitive adhesive sheet according to the present invention is, as described in the above requirement (II), present in a region (P) surrounded by a square having a side of 5 mm arbitrarily selected on the surface (α) and having a height of 1.5 μm or more at maximum. More than 95% of the plurality of recesses having a difference have different shapes.
FIG. 3 shows an example of a schematic plan view of the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention. As shown in FIG. 3, in the pressure-sensitive adhesive sheet of the present invention, among the plurality of recesses 13 existing on the surface (α) 12 a of the resin layer 12, the ratio of recesses having different shapes from each other is very large.
In terms of whether or not the requirement (II) is satisfied, for example, grooves described in a predetermined pattern determined in a predesigned shape are formed on the surface of the pressure-sensitive adhesive layer as described in Patent Document 1 above. The pressure sensitive adhesive sheet and the pressure sensitive adhesive sheet of the present invention are clearly distinguished.

Conventionally known pressure-sensitive adhesive sheet having a pre-designed shape on the surface of the pressure-sensitive adhesive layer and having grooves arranged on the surface in a predetermined pattern determined by the groove shape and groove arrangement, Even if one characteristic selected from air bleedability, appearance, adhesion characteristics, punching workability, and the like is improved, the other characteristics often deteriorate.
The present inventors, for example, pay attention to the fact that the shape of the groove contributing to the improvement of the air release property and the shape of the groove contributing to the improvement of the adhesive property are different from each other, and satisfy the requirement (II) The technical significance of was found.
That is, in the pressure-sensitive adhesive sheet of the present invention, the plurality of concave portions having different shapes existing in the region (P) on the surface (α) of the resin layer have air release properties, appearance, pressure-sensitive adhesive properties, punching properties, etc. The degree of contribution to improvement is also different. Therefore, by forming a plurality of recesses having different degrees of contribution to various characteristics, it is possible to obtain an adhesive sheet that improves these characteristics in a well-balanced manner.

In the pressure-sensitive adhesive sheet of one embodiment of the present invention, the ratio of the plurality of recesses having different shapes existing in the region (P) on the surface (α) of the resin layer is present in the region (P). Preferably it is 98% or more with respect to the total number (100%) of a recessed part, More preferably, it is 100%.

In the present invention, whether or not the above requirement (II) is satisfied is determined by selecting a region (P) on the surface (α) of the resin layer of the target pressure-sensitive adhesive sheet and being arbitrarily selected and having a side of 5 mm. ), The shape of a plurality of recesses having a height difference of 1.5 μm or more at maximum is observed with an electron microscope (magnification: 30 to 100 times), respectively, and the plurality of recesses existing in the region (P) If the number of recesses having different shapes from each other is 95% or more (preferably 98% or more, more preferably 100%), the recesses satisfying the above requirement (II) are on the surface ( α) Judged to be a pressure-sensitive adhesive sheet having a resin layer present thereon. In addition, the method of observing with the above-mentioned magnification directly with an electron microscope may be sufficient as observation of the shape of the above-mentioned plurality of crevices, an image is acquired using an electron microscope at the above-mentioned magnification, and a plurality of crevices shown in the image concerned The method of visually observing the shape may be used. More specifically, the determination is made based on the method described in the examples.
Here, “the number of recesses having different shapes is 100%” means “all of the plurality of recesses observed in the region (P) have different shapes”.

In the present specification, a recess continuously connected without interruption in the selected region is counted as “one recess”. However, for example, even if two recesses existing in the selected region are combined in another region adjacent to the region and formed as one recess, in the selected region, The two recesses are counted as independent ones.

<Requirement (III)>
As described in the requirement (III), the area ratio occupied by the recesses on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of the present invention is 16 to 95%.
Here, when the area ratio is less than 16%, the air-releasing property of the pressure-sensitive adhesive sheet becomes insufficient, and it is difficult to remove air pockets that may be generated when sticking to the adherend.
On the other hand, when the area ratio exceeds 95%, a sufficient adhesion surface between the surface (α) of the resin layer and the adherend cannot be secured, and the adhesive property may be deteriorated and peeling may occur. Moreover, the external appearance of the adhesive sheet obtained is also inferior.
From the above viewpoint, the area ratio of the plurality of recesses on the surface (α) is preferably 20 to 90%, more preferably 25 to 80%, still more preferably 30 to 75%, and still more preferably 35 to 70. %.

In the present invention, as shown in FIG. 3A, a region (Q) surrounded by a rectangle 50 of 200 μm long × 283.6 μm wide arbitrarily selected on the surface (α) 12a of the resin layer 12. 10 regions are selected, and the value of the area ratio occupied by the recesses in each region (Q) is calculated, and the average value of the values in the 10 regions is calculated as “the area occupied by the recesses on the surface (α) of the target adhesive sheet. It can also be regarded as a “ratio”.

That is, 10 values calculated by the following operations (i) and (ii) are obtained, and an average value of these 10 values is calculated as an area ratio of the concave portion on the “surface (α) of the pressure-sensitive adhesive sheet to be measured. Can also be considered. The specific methods of operations (i) to (ii) are as described in the examples.
Operation (i): As shown in FIG. 3A, a region surrounded by a rectangle 50 of 200 μm long × 283.6 μm wide arbitrarily selected on the surface (α) 12a of the resin layer 12 of the adhesive sheet The inside of (Q) is imaged using a laser microscope, and a three-dimensional image of the selected region (Q) is acquired.
Operation (ii): As shown in FIG. 3B, based on the three-dimensional image obtained in the above operation (i), does it correspond to a portion occupied by a recess having a maximum height difference of 1.5 μm or more? Depending on whether or not, a binarized image of the area (Q) subjected to image processing (binarization processing) is acquired. Next, an area S occupied by the concave portion in the binarized image of the region (Q) is obtained using image analysis software. Then, based on the calculation formula “[area ratio (%)] = S / total area of region (Q) × 100”, the area ratio occupied by the recesses in the selected region (Q) is calculated.

Note that a region larger than the region (Q) may be selected instead of the region (Q) described above.
That is, instead of the above-described region (Q), 10 regions selected from rectangles or squares having a side of 200 μm or more and 10 mm or less are selected, the same measurement is performed, and the average value of the values in the 10 regions is calculated. It can also be regarded as “the area ratio occupied by the recesses on the surface (α)” of the target pressure-sensitive adhesive sheet.

In the present invention, as a digital microscope, for example, product names “Digital Microscope VHX-1000” and “Digital Microscope VHX-5000” manufactured by Keyence Corporation can be used.

In one embodiment of the present invention, it is preferable that a plurality of the recesses exist in the region (Q).
The number of the concave portions present in the region (Q) is preferably 2 or more, more preferably 3 or more, and preferably 1000 or less, more preferably 500 or less.

<Requirement (IV)>
In the pressure-sensitive adhesive sheet of one embodiment of the present invention, as described in the above requirement (IV), it is preferable that a plurality of concave portions having a height difference of 1.5 μm or more are irregularly present on the surface (α) of the resin layer. .
In the present invention, “a plurality of recesses are irregularly present” means that the positions where the plurality of recesses exist are irregular (random) without having the same repeating pattern (a plurality of recesses are formed). State without periodicity). In other words, like the groove described in Patent Document 1, that is, a groove formed by transferring an emboss pattern such as pressing a release material having an emboss pattern against the surface of the resin layer, the “arrangement” Is different from the state of
By having a plurality of concave portions irregularly, it is possible to provide a pressure-sensitive adhesive sheet in which various properties such as air leakage and pressure-sensitive adhesive properties are improved in a well-balanced manner.

Whether or not “a plurality of recesses are irregularly present” is determined by visually observing the positions of the plurality of recesses on the surface (α) of the resin layer of the target pressure-sensitive adhesive sheet, a digital microscope, or an electron microscope. In principle, it is determined by observing (magnification: 30 to 100 times).
However, an arbitrarily selected region on the surface (α) surrounded by a square with a side of 1 to 10 mm (preferably a region (P) surrounded by a square with a side of 5 mm) is selected and exists in the region. The position of the plurality of recesses may be determined by observing with a digital microscope or an electron microscope (magnification: 30 to 100 times). That is, when there is no regularity in the “positions of the plurality of recesses” present in the selected area, the target adhesive sheet can be regarded as satisfying the requirement (IV).
Further, the observation of the formation positions of the plurality of recesses described above may be a method of directly observing with an electron microscope at the above magnification, and an image is obtained using the electron microscope at the above magnification, and a plurality of A method of visually observing the formation position of the recess may be used.

<Requirement (V)>
As for the adhesive sheet of 1 aspect of this invention, it is preferable that the shape of the sticking surface on the surface ((alpha)) of a resin layer is an indeterminate form as the said requirement (V).
In the present invention, the “applied surface on the surface (α)” is the surface excluding the range occupied by the plurality of recesses on the surface (α) of the resin layer, It means the surface to be bonded to the body.
In the schematic plan view shown in FIG. 3A, the “sticking surface” refers to a white portion of the surface (α) 12a of the resin layer excluding the plurality of recesses 13.
Further, “the shape of the affixed surface is indefinite” means that the affixed surface has only a circle or a straight line, as in the shape of the white portion of the surface (α) 12a of the resin layer shown in FIG. It means that the shape does not have a specific shape such as an enclosed shape (triangle, square, etc.) and does not have a predetermined repetitive pattern. That is, the shape of the pasting surface formed by transferring the emboss pattern such as pressing the release material having the emboss pattern against the surface of the resin layer is excluded.
In other words, in the pressure-sensitive adhesive sheet that satisfies the requirements (II) and (IV), the shape of the sticking surface on the surface (α) of the resin layer is considered to be indefinite.
Since the shape of the sticking surface on the surface (α) of the resin layer is indefinite, it is possible to obtain a pressure-sensitive adhesive sheet in which various characteristics such as air release and pressure-sensitive adhesive characteristics are improved in a balanced manner.

Whether or not “the shape of the pasting surface on the surface (α) is indefinite” is determined by visually or digitally examining the shape of the pasting surface on the surface (α) of the resin layer of the target adhesive sheet. In principle, it is determined by observation with an electron microscope (magnification: 30 to 100 times).
However, an arbitrarily selected area on the surface (α) surrounded by a square with a side of 1 to 10 mm (preferably, an area (P) surrounded by a square with a side of 5 mm) is selected, and affixed within the area The shape of the surface may be judged by observing with a digital microscope or an electron microscope (magnification: 30 to 100 times). That is, when it is determined that the “shape of the pasting surface” in the selected region is indefinite, the target adhesive sheet can be regarded as satisfying the requirement (V).
Further, the observation of the shape of the affixed surface may be a method of directly observing with a digital microscope or an electron microscope at the above magnification, and an image is obtained using the digital microscope or the electron microscope at the above magnification and shown in the image. A method of visually observing the shape of the applied surface is also possible.

Hereinafter, each structure of the adhesive sheet of this invention is demonstrated.
〔Base material〕
The substrate used in one embodiment of the present invention is not particularly limited, and examples thereof include a paper substrate, a resin film or sheet, a substrate obtained by laminating a paper substrate with a resin, and the like. It can select suitably according to the use of a sheet | seat.
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.

The thickness of the substrate is appropriately set according to the use of the pressure-sensitive adhesive sheet of the present invention, but is preferably 5 to 1000 μm, more preferably 10 to 500 μm, and still more preferably 12 to 12 from the viewpoint of handleability and economy. 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 one embodiment of the present invention is preferably a non-breathable base material from the viewpoint of improving the blister resistance of the obtained pressure-sensitive adhesive sheet, and specifically, the surface of the above-described resin film or sheet. A substrate having a metal layer thereon is preferred.
Examples of the metal formed by 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. 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 a release material used in one embodiment of the present invention, a release sheet that has been subjected to a double-sided release treatment, a release sheet that has been subjected to a single-sided release treatment, or the like is used. Can be mentioned. 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]
The resin layer of the pressure-sensitive adhesive sheet of the present invention includes a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles.
In the pressure-sensitive adhesive sheet of the present invention, at least the surface (α) of the resin layer on the side 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 provided side may also have adhesiveness.

As the resin layer, a layer (Xβ) mainly containing a resin part (X) and a layer containing 15% by mass or more of a particle part (Y) from the substrate or release material side, such as the adhesive sheet 1a of FIG. A configuration of a layer formed by forming a multilayer structure in which (Y1) and a layer (Xα) mainly including the resin portion (X) are stacked in this order can be given.
Note that the structure of the multilayer structure described above is a mixed structure in which 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. There may be.

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 constituting the resin part (X).
The layer (Xβ) and the layer (Xα) may further have a void portion (Z) described later in addition to the resin portion (X) and the particle portion (Y).

As the content of the resin in the layer (Xβ) and the layer (Xα), it is usually 50 to 100% by mass with respect to the total mass (100% by mass) of the layer (Xβ) or the layer (Xα), It is preferably 65 to 100% by mass, more preferably 75 to 100% by mass, still more preferably 85 to 100% by mass, and still more preferably 90 to 100% by mass.
In addition, in this invention, "content of the resin in a layer (X (beta)) and a layer (X (alpha))""is the whole quantity (100 mass% (100 mass% ( However, it can be regarded as the content of the resin in a)) except for the dilution solvent.

Moreover, as content of the microparticles | fine-particles which comprise the particle | grain part (Y) in a layer (X (beta)) and a layer (X (alpha)), respectively independently to the total mass (100 mass%) of a layer (X (beta)) or a layer (X (alpha)). On the other hand, it is less than 15% by mass, 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.
Further, the layer (Xβ) and the layer (Xα) are each preferably formed from a composition (xβ) or (xα) containing a resin as a main component described later.

The layer (Y1) containing 15% by mass or more of the particle part (Y) may be a layer composed only of the particle part (Y), or may be a layer containing the resin part (X) together with the particle part (Y). Moreover, you may have the space | gap part (Z) mentioned later further.
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), but preferably 20 to 100%. The amount is by mass, more preferably from 25 to 90% by mass, still more preferably from 30 to 85% by mass, still more preferably from 35 to 80% by mass.
In the present invention, “the content of the fine particles in the layer (Y1)” means the fine particles in the total amount (100% by mass (excluding the diluting solvent)) of the composition that is a forming material of the layer (Y1). It can also be regarded as the content of.
The content of the resin in the layer (Y1) is usually 1 to 85% by mass, preferably 5 to 80% by mass, more preferably 10%, based on the total mass (100% by mass) of the layer (Y1). It is ˜75% by mass, more preferably 20 to 70% by mass, and still more preferably 25 to 65% by mass.
In addition, in this invention, "content of the resin in a layer (Y1)" is resin in the whole quantity (100 mass% (however, except a dilution solvent)) of the composition which is the formation material of the said layer (Y1). It can also be regarded as the content of.
Moreover, it is preferable that the said layer (Y1) is a layer formed from the composition (y) which contains the below-mentioned microparticles | fine-particles 15 mass% or more.

It is preferable that the resin layer which the adhesive sheet of 1 aspect 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 in this manner, the resin layer included in the pressure-sensitive adhesive sheet according to one embodiment of the present invention has a concave portion on the surface (α). Therefore, it can be excellent in air bleeding and blister resistance.

In addition, the shear storage elastic modulus at 100 ° C. of the resin layer included in the pressure-sensitive adhesive sheet of one embodiment of the present invention is preferably 9.0 × 10 ³ Pa or more from the viewpoint of improving the air release property and blister resistance of the pressure-sensitive adhesive sheet. More preferably, it is 1.0 × 10 ⁴ Pa or more, and further 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.

The adhesive force on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet of one embodiment 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. More preferably, it is 4.0 N / 25 mm or more, and still 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.

<Resin part (X)>
The resin part (X) constituting the resin layer contains a resin as a main component.
In the present invention, the resin portion (X) is a portion containing components other than the fine particles contained in the resin layer, and is distinguished from the particle portion (Y) in that respect.
The resin part (X) contains a resin as a main component and may contain a crosslinking agent or a general-purpose additive in addition to the resin.

The resin content in the resin part (X) is usually 40% by mass or more, preferably 50% by mass or more, more preferably 65% by mass or more, based on the total amount (100% by mass) of the resin part (X). More preferably, it is 75 mass% or more, More preferably, it is 85 mass% or more, More preferably, it is 90 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) preferably contains an adhesive resin.

Examples of the adhesive resin include acrylic resins, urethane resins, rubber resins, and silicone resins.
Among these adhesive resins, the adhesive properties and weather resistance are good, and it is easy to form a plurality of recesses that satisfy the above requirements (I) to (III) on the surface (α) of the formed resin layer. From the viewpoint, it is preferable to include an acrylic resin.
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). To 100% by mass, more preferably 80 to 100% by mass, and still more preferably 100% by mass.

Further, from the viewpoint of easily forming a plurality of recesses that satisfy the above requirements (I) to (III) on the surface (α) of the formed resin layer, the resin portion (X) is a resin having a functional group. It is preferable to include, and it is more preferable to include 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.

In addition, it is preferable that resin part (X) contains a crosslinking agent further with resin which has the said functional group. In particular, when the resin layer has the multilayer structure, 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 crosslinking 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 whose metal atoms are aluminum, zirconium, titanium, zinc, iron, tin, etc., and form a plurality of recesses that satisfy the above requirements (I) to (III). From the viewpoint of facilitating, an aluminum chelate crosslinking agent is preferable.
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 a plurality of recesses that satisfy the above requirements (I) to (III) on the surface (α) of the formed resin layer, the resin portion (X) is a metal chelate-based crosslink. It is preferable that 1 or more types chosen from an agent, an epoxy type crosslinking agent, and an aziridine type crosslinking agent are included, It is more preferable that a metal chelate type crosslinking agent is included, It is still more preferable that an aluminum chelate type crosslinking agent is included.

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 0.3 to 7.0 parts with respect to 100 parts by mass of the resin having a functional group. Part by mass.

Moreover, it is preferable that resin part (X) contains both a metal chelate type crosslinking agent and an epoxy-type crosslinking agent from a viewpoint of making the shape maintenance property of several recessed part on the surface ((alpha)) of a resin layer favorable.
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.

Moreover, the resin part (X) may contain a general-purpose additive.
Examples of the general-purpose additive include tackifiers, 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 90,000. 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. % By mass, more preferably 80 to 100% by mass, and still more preferably 90 to 100% by 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.

The number of carbon atoms of the alkyl group contained in the monomer (a1 ′) is more preferably 4 to 12, further preferably 4 to 8, and still more preferably 4 to 6, from the viewpoint of improving the adhesive property.
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, 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 weight, more preferably 60 to 99% by weight, based on all the structural units (100% by weight) of the acrylic copolymer (A1). More preferably, it is 70 to 95% by mass, and still more preferably 80 to 93% by 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 to 30% by mass, and still more preferably 7 to 20% by 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 weight, more preferably 0 to 20% by weight, still more preferably based on the total structural unit (100% by weight) of the acrylic copolymer (A1). Is 0 to 10% by mass, more preferably 0 to 5% by mass.
The above monomers (a1 ′) to (a3 ′) may be used alone or in combination of two or more.

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. The above-described requirements are included in the viewpoint of improving the adhesive properties and the surface (α) of the formed resin layer. From the viewpoint of facilitating formation of a plurality of recesses satisfying (I) to (III), the metal chelate preferably contains one or more selected from metal chelate crosslinking agents, epoxy crosslinking agents, and aziridine crosslinking agents. It is more preferable to include a system cross-linking agent, and it is further preferable to include an aluminum chelate-based cross-linking agent.
Moreover, it is preferable that both a metal chelate type crosslinking agent and an epoxy type crosslinking agent are included as a crosslinking agent (B) from a viewpoint of making the shape maintenance property of several recessed part on the surface ((alpha)) of a resin layer favorable.

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 to 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.

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. To 100% by mass, more preferably 80 to 100% by mass, and still more preferably 100% by mass.

<Particle part (Y)>
The particle portion (Y) constituting the resin layer is made of fine particles.
As the average particle size of the fine particles, a plurality of the above requirements (I) to (III) satisfying the above requirements (I) to (III) on the viewpoint of improving the air bleeding property and blister resistance of the pressure-sensitive adhesive sheet and the surface (α) of the formed resin layer From the viewpoint of facilitating the formation of the recess, the thickness is preferably 0.01 to 100 μm, more preferably 0.05 to 25 μm, and still more preferably 0.1 to 10 μm.

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. .
Further, the volume average secondary particle diameter of the silica particles used in one embodiment of the present invention is described above in terms of improving the air bleeding property and blister resistance of the pressure-sensitive adhesive sheet, and on the surface (α) of the formed resin layer. From the viewpoint of facilitating the formation of a plurality of recesses that satisfy the requirements (I) to (III), the thickness is preferably 0.5 to 10 μm, more preferably 1 to 8 μm, 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 the resin layer of the pressure-sensitive adhesive sheet of one embodiment of the present invention is heated 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%. % By mass, more preferably 9 to 60% by 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. Further, when the pressure-sensitive adhesive sheet of the present invention is produced, a plurality of recesses that satisfy the above requirements (I) to (III) are easily formed on the surface (α) of the formed resin layer. On the other hand, if the mass retention is 90% by mass or less, the pressure-sensitive adhesive sheet can have a high film strength and excellent water resistance and chemical resistance.

[Method for producing adhesive sheet]
Next, the manufacturing method of the adhesive sheet of this invention is demonstrated.
The method for producing the pressure-sensitive adhesive sheet of the present invention is not particularly limited, but a plurality of materials satisfying the above-mentioned requirements (I) to (III) on the viewpoint of productivity and the surface (α) of the formed resin layer. From the viewpoint of easily forming the recess, a method having at least the following steps (1) and (2) is preferable.
Step (1): Forming a coating film (x ′) composed of a composition (x) containing a resin as a main component and a coating film (y ′) composed of a composition (y) containing 15% by mass or more of the fine particles. Step Step (2): Step of simultaneously drying the coating film (x ′) and the coating film (y ′) formed in the step (1)

<Step (1)>
Step (1) forms a coating film (x ′) composed of a composition (x) containing a resin as a main component and a coating film (y ′) composed of a composition (y) containing 15% by mass or more of the fine particles. It is a process to do.
The composition (x) 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 the above-mentioned general-purpose additives.
The composition (y) is a material for forming the particle portion (Y), but may further contain a resin, a crosslinking agent, and the above-mentioned general-purpose additives. The composition (y) containing components such as these resins also serves as a material for forming the resin portion (X).

(Composition (x))
Examples of the resin contained in the composition (x) include a resin constituting the above-described resin portion (X), and an adhesive resin having a functional group is preferable, and an acrylic resin (A) having the above-described functional group. Is more preferable, and the above-mentioned acrylic copolymer (A1) is preferable.
The content of the resin in the composition (x) is usually 40% by mass or more, preferably 50% by mass or more, based on the total amount of the composition (x) (100% by mass (excluding the dilution solvent)), More preferably 65% by mass or more, more preferably 75% by mass or more, further preferably 85% by mass or more, still more preferably 90% by mass or more, and preferably 100% by mass or less, more preferably 95% by mass. It is as follows.

Moreover, as a crosslinking agent contained in a composition (x), although the crosslinking agent contained in the above-mentioned resin part (X) is mentioned, a composition (x) is a metal chelate type crosslinking agent, an epoxy type crosslinking | crosslinking. It is preferable that 1 or more types chosen from an agent and an aziridine type crosslinking agent are included, and it is more preferable that a metal chelate type crosslinking agent is included.
Furthermore, from the viewpoint of improving the shape maintaining property of the plurality of recesses on the surface (α) of the resin layer to be formed, the composition (x) may contain both a metal chelate crosslinking agent and an epoxy crosslinking agent. preferable.
When the composition (x) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent, the content ratio of the metal chelate crosslinking agent and the epoxy crosslinking agent in the composition (x) [metal chelate crosslinking agent / epoxy The 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 to 98.5 by mass ratio. /1.5, more preferably 75/25 to 98.0 / 2.0.

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 (x). 3 to 7.0 parts by mass.

The composition (x) is preferably an acrylic pressure-sensitive adhesive containing the above-mentioned acrylic resin (A) having a functional group and a crosslinking agent (B), and the above-mentioned acrylic copolymer (A1) and cross-linking. The acrylic pressure-sensitive adhesive containing the agent (B) is more preferable.
The details of the acrylic pressure-sensitive adhesive are as described above.

The composition (x) may contain the above-mentioned fine particles, but the content of the fine particles is less than 15% by mass and more than the content of the resin contained in the composition (x). Few.
The specific fine particle content is less than 15% by mass, preferably 0 to 13% by mass, based on the total amount of the composition (x) (100% by mass (excluding the dilution solvent)). More preferably, it is 0 to 10% by mass, still more preferably 0 to 5% by mass, and still more preferably 0% by mass.

(Composition (y))
The composition (y) is a material for forming the particle part (Y), and contains at least 15% by mass of the fine particles described above. From the viewpoint of fine particle dispersibility, the composition (y) preferably contains a resin together with the fine particles. It is more preferable to contain a crosslinking agent together with the resin. Moreover, the composition (y) may contain a general purpose additive.
In addition, these resin, a crosslinking agent, and a general purpose additive become a forming material of resin part (X).

Examples of the fine particles contained in the composition (y) 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 (y) is such that the composition (y) is formed on the surface (α) of the resin layer from the viewpoint of facilitating the formation of an irregular recess formed by self-formation of the resin layer. Is 15% by mass or more, preferably 20 to 100% by mass, more preferably 25 to 90% by mass, and still more preferably 30 to 85%. The mass is more preferably 35 to 80% by mass.

As resin contained in a composition (y), the same thing as resin contained in the above-mentioned composition (x) is mentioned, It is preferable that the same resin as composition (x) is included. In addition, you may use these resin individually or in combination of 2 or more types.
Further, as a more specific resin contained in the composition (y), a resin having a functional group is preferable, an acrylic resin (A) having the above-described 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 1 to 85% by mass, preferably 5 to 80% by mass with respect to the total amount of the composition (y) (100% by mass (excluding the diluting solvent)). %, More preferably 10 to 75% by mass, still more preferably 20 to 70% by mass, and still more preferably 25 to 65% by mass.

Moreover, as a crosslinking agent contained in a composition (y), although the crosslinking agent contained in the above-mentioned resin part (X) is mentioned, a composition (y) is a metal chelate type crosslinking agent, an epoxy type crosslinking | crosslinking. It is preferable that 1 or more types chosen from an agent and an aziridine type crosslinking agent are included, and it is more preferable that a metal chelate type crosslinking agent is included. Furthermore, the composition (y) preferably contains both a metal chelate crosslinking agent and an epoxy crosslinking agent.
In addition, when composition (y) contains both a metal chelate type crosslinking agent and an epoxy type crosslinking agent, suitable content ratio (mass ratio) of the metal chelate type crosslinking agent and epoxy type crosslinking agent in composition (y) Is the same as that of the above-mentioned composition (x).
The content of the cross-linking 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 (y). 3 to 7.0 parts by mass.

(Formation method of coating film (x ′), (y ′))
In addition, when forming a coating film, in order to make it easy to form a coating film, it is preferable to mix | blend a solvent with composition (x) and (y), and make it the form of the solution of a composition.
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 order of laminating the coating films (x ′) and (y ′) formed in this step is not particularly limited, but the coating film (x ′) should be laminated on the coating film (y ′). Is preferred.
As a method for forming the coating films (x ′) and (y ′), after the coating film (y ′) is formed, the coating film (x ′) may be sequentially formed on the coating film (y ′). Further, from the viewpoint of productivity, a method of simultaneously forming the coating film (y ′) and the coating film (x ′) with a multilayer coater may be used.
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.

In this step (1), after the formation of at least one of the coating film (x ′) and the coating film (y ′), before proceeding to the step (2), the pre-treatment is such that the curing reaction of the coating film does not proceed. You may give a drying process.
In this step (1), the drying temperature at the time of performing the pre-drying treatment is usually appropriately set within a temperature range in which the formed coating film does not proceed, but preferably in step (2). Is lower than the drying temperature. The specific drying temperature indicated by the phrase “below the drying temperature in step (2)” is preferably 10 to 45 ° C., more preferably 10 to 34 ° C., and further preferably 15 to 30 ° C.

<Step (2)>
Step (2) is a step of simultaneously drying the coating film (x ′) and the coating film (y ′) formed in step (1).
In this step, by simultaneously drying the formed coating film (x ′) and coating film (y ′), a resin layer containing the resin part (X) and the particle part (Y) is formed, and A plurality of recesses are formed on the surface (α) of the resin layer.

The drying temperature in this step is preferably 35 to 200 ° C. from the viewpoint of easily forming a plurality of recesses that satisfy the above requirements (I) to (III) on the surface (α) of the resin layer to be formed. The temperature is more preferably 60 to 180 ° C, still more preferably 70 to 160 ° C, and still more preferably 80 to 140 ° C.
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.

A void portion (Z) can be formed around the particle portion (Y) of the resin layer formed by this step.
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).

Moreover, like the adhesive sheet 1a of Fig.1 (a), the layer (X (beta)) mainly containing the resin part (X), the layer (Y1) containing 15 mass% or more of particle parts (Y), and mainly resin When manufacturing the adhesive sheet which has the resin layer formed by forming the multilayer structure which laminated | stacked the layer (X (alpha)) containing part (X) in this order, the manufacturing method of the 1st and 2nd aspect shown below is preferable.
In the description of the production methods of the first and second aspects below, “the composition (xβ) or (xα) containing a resin as a main component” is the same as the above-described composition (x), and the composition The details of each component contained in the product (xβ) or (xα) (type of component, suitable component, component content, etc.) are also the same. The “composition (y) containing 15% by mass or more of fine particles” is also as described above.

[Production Method of First Embodiment]
The manufacturing method of the first aspect includes at least the following steps (1A) and (2A).
Step (1A): a coating film (xβ ′) made of a composition (xβ) containing a resin as a main component on a substrate or a release material, and a coating film made of a composition (y) containing 15% by mass or more of the fine particles. (Y ′) and a coating film (xα ′) made of a composition (xα) containing a resin as a main component is laminated and formed in this order. Step (2A): Coating film formed in step (1A) ( xβ ′), coating film (y ′), and coating film (xα ′) are simultaneously dried.

Also in the step (1A), it is preferable that the composition (xβ), 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 (xβ ′), the coating film (y ′), and the coating film (xα ′), the coating film (xβ ′) is formed on the substrate or the release material, and then the coating film (xβ A method of sequentially forming using a coater as described above may be used, such as forming a coating film (y ') on the coating film (y) and forming a coating film (xα') on the coating film (y '). The film (xβ ′), the coating film (y ′), and the coating film (xα ′) may be formed by simultaneous application using the multilayer coater.

In this step (1A), after forming one or more coating films (xβ ′), coating film (y ′), and coating film (xα ′), before moving to step (2A), You may perform the predrying process of the grade which the hardening reaction of the said coating film does not advance.
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 this 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 cure, but preferably in step (2A). Is lower than the drying temperature. The specific drying temperature indicated by the phrase “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.

The step (2A) is a step of simultaneously drying the coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) formed in the step (1A). The range is the same as in step (2) above. By this step, a resin layer including the resin portion (X) and the particle portion (Y) is formed.

[Production Method of Second Aspect]
As a manufacturing method of a 2nd aspect, it has the following process (1B) and (2B) at least.
Step (1B): a coating film comprising a composition (y) containing 15% by mass or more of the fine particles on a layer (Xβ) mainly containing a resin portion (X) provided on a substrate or a release material ( Step (2B): A coating film (y) formed by laminating and forming a coating film (xα ′) made of a composition (xα) containing a resin as a main component in this order (y ′) ') And the step of simultaneously drying the coating film (xα')

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 ′) composed of a composition (xβ) containing a resin as a main component is formed on a substrate or a release material, and the coating film (xβ ′) is dried. Can be formed.
The drying temperature at this time is not particularly limited, and is preferably 35 to 200 ° C, more preferably 60 to 180 ° C, still more preferably 70 to 160 ° C, and still more preferably 80 to 140 ° C.

In this embodiment, the coating film (y ′) 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 first aspect described above.
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.

In this step (1B), after the formation of the coating film (y ′), or after the formation of the coating film (y ′) 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.
In this step (1B), the drying temperature at the time of performing the pre-drying treatment is usually appropriately set within a temperature range in which the formed coating film does not cure, but preferably in step (2B). Is lower than the drying temperature. The specific drying temperature indicated by the phrase “below the drying temperature in step (2B)” is preferably 10 to 45 ° C., more preferably 10 to 34 ° C., and further preferably 15 to 30 ° C.

The step (2B) is a step of simultaneously drying the coating film (y ′) and the coating film (xα ′) formed in the step (1B). The preferred range of the drying temperature in this step is the above-described step (2). ). By this step, a resin layer including the resin portion (X) and the particle portion (Y) is formed.

[Adhesive sheet of another embodiment of the present invention]
Examples of the pressure-sensitive adhesive sheet according to another aspect of the present invention include pressure-sensitive adhesive sheets (1) to (5) shown in the following [1] to [5]. Details of the constituent elements of the pressure-sensitive adhesive sheets (1) to (5) are as described above.

[1] A resin layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or the release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
A pressure-sensitive adhesive sheet (1), wherein a concave portion exists on the surface (α), and an area ratio of the concave portion on the surface (α) is 16 to 95%.

[2] A resin layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or the release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
There are a plurality of recesses having a height difference of 1.5 μm or more in the region (P) arbitrarily selected on the surface (α) surrounded by a square with a side of 5 mm, and the recesses on the surface (α) A pressure-sensitive adhesive sheet (2) having an area ratio of 16 to 95%.

[3] A resin layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or the release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
On the surface (α), a plurality of recesses are present irregularly,
The pressure-sensitive adhesive sheet (3), wherein the area ratio of the concave portion on the surface (α) is 16 to 95%.

[4] A resin layer including a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or the release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
There are recesses on the surface (α), and the area ratio of the recesses on the surface (α) is 16 to 95%,
The adhesive sheet (4) whose shape of the sticking surface on the surface ((alpha)) is an indeterminate form.

[5] A resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on a base material or a release material, and at least the base material or release material is provided The surface (α) of the resin layer opposite to the formed side is an adhesive sheet having adhesiveness,
There are recesses on the surface (α), and the area ratio of the recesses on the surface (α) is 16 to 95%,
The pressure-sensitive adhesive sheet (5), wherein the concave portion is not formed by transferring an emboss pattern.

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 (product name “HLC-8020” manufactured by Tosoh Corporation), measurement was performed under the following conditions, and values measured in terms of standard polystyrene were used.
(Measurement condition)
Column: “TSK guard column HXL-L”, “TSK gel G2500HXL”, “TSK gel G2000HXL”, and “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>
The thickness of the resin layer was measured by observing the cross section of the resin layer of the target pressure-sensitive adhesive sheet using a scanning electron microscope (manufactured by Hitachi, Ltd., product name “S-4700”).

Production examples x-1 to 6
(Preparation of resin composition solutions (x-1) to (x-6))
To 100 parts by mass of the acrylic resin having the type and solid content described in Table 1, the type and blending amount of crosslinking agent and dilution solvent described in Table 1 are added, and the solid content concentration shown in Table 1 is added. Resin compositions solutions (x-1) to (x-6) were respectively prepared.

The details of each component shown in Table 1 used for preparing the resin composition solutions (x-1) to (x-6) are as follows.
<Acrylic resin solution>
Solution (i): Acrylic resin (xi) (acrylic copolymer having structural units derived from butyl acrylate (BA) and acrylic acid (AA), BA / AA = 90/10 (mass%) , Mw: 470,000), a mixed solution of toluene and ethyl acetate having a solid content concentration of 33.6% by mass.
Solution (ii): Acrylic resin (x-ii) (acrylic resin having structural units derived from butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), vinyl acetate (VAc), and acrylic acid (AA) A mixed solution of toluene and ethyl acetate having a solid content concentration of 43.0% by mass, containing a copolymer, BA / 2EHA / VAc / AA = 46/37/10/7 (% by mass), Mw: 370,000).
<Crosslinking agent>
Aluminum chelate crosslinking agent: Product name “M-5A”, manufactured by Soken Chemical Co., Ltd., solid content concentration = 4.95% by mass.
Epoxy-based cross-linking agent: A solution of an epoxy-based cross-linking 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%.
-Isocyanate-based crosslinking agent: Product name “Coronate L”, manufactured by Tosoh Corporation, solid content concentration = 75% by mass.
Aziridine-based crosslinking agent: product name “BXX5134”, manufactured by Toyochem Co., Ltd., solid content concentration = 5% by mass.
<Diluted solvent>
IPA: isopropyl alcohol.
AcOEt: ethyl acetate.

Production Example y-0
(Preparation of fine particle dispersion (y-0))
Solution (i) containing acrylic resin (xi) (acrylic copolymer having structural units derived from butyl acrylate (BA) and acrylic acid (AA) (BA / AA = 90/10 (mass%)) , Mw: 470,000) containing 100 parts by mass (solid solution: 33.6 parts by mass) of a mixed solution of toluene and ethyl acetate having a solids concentration of 33.6% by mass, Add 50.4 parts by mass (solid content: 50.4 parts by mass) of product name “Nip seal E-200A”, manufactured by Tosoh Silica Co., Ltd., volume average secondary particle size: 3 μm, and add fine particles. Dispersion was carried out to prepare a fine particle dispersion (y-0) containing an acrylic resin and silica particles and having a solid content concentration of 30% by mass.

Production Examples y-1 to 8
(Preparation of coating solutions (y-1) to (y-8) for forming a coating film (y ′))
For the fine particle dispersion (y-0) prepared in Production Example y-0 having the blending amount shown in Table 2, the acrylic resin solution, crosslinking agent, and diluent solvent having the kind and blending amount shown in Table 2 Were added to prepare coating solutions (y-1) to (y-8) for forming a coating film (y ′) having a solid content concentration shown in Table 2.

The details of each component shown in Table 2 used for preparing the coating liquids (y-1) to (y-8) for forming the coating film (y ′) are as follows.
<Acrylic resin solution>
Solution (i): Acrylic resin (xi) (details are as described above).
<Crosslinking agent>
Aluminum chelate crosslinking agent: Product name “M-5A”, manufactured by Soken Chemical Co., Ltd., solid content concentration = 4.95% by mass.
Epoxy-based cross-linking agent: A solution of an epoxy-based cross-linking 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%.
<Diluted solvent>
IPA: isopropyl alcohol.
IPA / CHN: Mixed solvent consisting of isopropyl alcohol (IPA) and cyclohexanone (CHN) (IPA / CHN = 60/40 (mass ratio)).

Examples 1-8
(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.
Using an applicator, the resin composition solution (x-1) prepared in Production Example x-1 is applied onto the aluminum vapor-deposited layer of the PET film. Was applied to form the coating film (xβ ′).
Next, on the formed coating film (xβ ′), using an applicator, any one of coating liquids (y-1) to (y-4) for forming a coating film (y ′) of the type shown in Table 3 is used. , So that the total thickness of the two layers of the coating (xβ ′) and the coating (y ′) after repeated coating (the total thickness of the two layers in the non-dried state) is as shown in Table 3. Thus, a coating film (y ′) was formed.
Then, on the formed coating film (y ′), using the applicator, the resin composition solution (x-1) prepared in Production Example x-1 was overcoated with the coating film (xβ ′) The coating film (y ′) and the coating film (xα ′) were applied so that the total thickness of the three layers (the total thickness of the three layers in the non-dried state) was the thickness shown in Table 3. xα ′) was formed.
(2) Drying treatment Subsequently, the 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 part (X ) And a particle portion (Y), a pressure-sensitive adhesive sheet with a base material having a resin layer having a thickness shown in Table 3 was prepared.

Example 9
A 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.
Using a knife coater, the resin composition solution (x-2) prepared in Production Example x-2 was applied onto the aluminum vapor-deposited layer of the PET film. The film (thickness) was applied to a thickness of 25 μm to form a coating film (xβ ′). And it was made to dry for 2 minutes at the drying temperature of 100 degreeC, and the layer (X (beta)) containing the resin part (X) was formed.
Furthermore, the surface of the formed layer (Xβ) and a release film of a release film (product name “SP-PET 381031”, manufactured by Lintec Corporation, PET film with a silicone release agent layer on one side, thickness 38 μm) The laminate was laminated so as to be bonded to the surface, and a laminate having a layer (Xβ) was once produced.
Next, on the surface of the layer (Xβ) exposed by peeling the release film of the laminate, a coating solution (y ′) for forming a coating film (y ′) prepared in Production Example y-1, and The resin composition solution (x-1) prepared in Production Example x-1 was simultaneously applied with a multilayer die coater (width: 500 mm), and a coating film (y ′) and a coating film (xα) were formed on the layer (Xβ). ') Simultaneously formed in this order. In the setting of the multilayer die coater, the thickness of the coating film (y ′) was set to 55 μm and the thickness of the coating film (xα ′) was set to 65 μm to form each coating film.
The two-layer coating film (y ′) and coating film (xα ′) are simultaneously dried at a drying temperature of 100 ° C. for 2 minutes, and include a resin part (X) and a particle part (Y). A pressure-sensitive adhesive sheet with a base material having a resin layer having a thickness shown in 3 was prepared.

Comparative Example 1
In Example 1, a coating film (y ′) and a coating film (xα ′) were not formed, and a preparation was made in Production Example x-1 using a knife coater on an aluminum vapor deposition layer of a PET film used as a substrate. The resin part (X-1) was applied in the same manner as in Example 1 except that the resin composition solution (x-1) was applied so that the film thickness after drying was 25 μm to form a coating film (xβ ′). The adhesive sheet with a base material which has a 25-micrometer-thick resin layer which consists only of this was produced.

Comparative Example 2
A 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 PET film, using an applicator, the resin composition solution (x-1) prepared in Production Example x-1 was applied to form a coating film (xβ ′). And dried for 2 minutes to form a layer (Xβ) having a thickness of 5 μm including the resin portion (X).
Separately from the above, using an applicator on the release agent layer of a release film (product name “SP-PET 381031” manufactured by Lintec Corporation, PET film having a silicone release agent layer on one side, thickness 38 μm), A coating film (y ′)-forming coating solution (y-1) prepared in Production Example y-1 was applied to form a coating film (y ′), and then dried at 100 ° C. for 2 minutes to obtain a resin part (X ) And a particle portion (Y), a layer (Y1) having a thickness of 15 μm was formed.
Further, separately from the above, the resin composition solution (x-1) prepared in Production Example x-1 was applied onto the release agent layer of the same type of release film as described above by using an applicator. After forming xα ′), the film was dried at 100 ° C. for 2 minutes to form a layer (Xα) having a thickness of 5 μm including the resin portion (X).
And it laminated so that the surface of the layer (X (beta)) formed on the PET film which is a base material and the surface which the layer (Y1) formed as mentioned above exposed may be bonded. Furthermore, the surface of the layer (Y1) exposed by removing the release film on the layer (Y1) and the surface exposed of the layer (Xα) formed as described above were laminated.
In this way, the layer (Xβ), the layer (Y1), and the layer (Xα) are laminated in this order on the base material, and includes the resin part (X) and the particle part (Y). A pressure-sensitive adhesive sheet with a base material having a resin layer having a thickness of 25 μm was prepared.

Examples 10 to 16
A 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.
Any one of the resin composition solutions (x-1) to (x-6) prepared in Production Examples x-1 to 6 on the aluminum vapor deposition layer of the PET film at a flow rate and a coating speed shown in Table 4. In addition, using any one of the coating liquids (y-1) to (y-8) for forming the coating film (y ′) prepared in Production Examples y-1 to 8, a multilayer die coater (width: 250 mm) is used simultaneously. It applied and formed simultaneously in order of the coating film (x (beta) '), the coating film (y'), and the coating film (x (alpha) ') from the base-material side.
The types of the resin composition solution and coating film (y ′) forming coating solution used as the material for forming each coating film are as shown in Table 4.
Then, the three-layer coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) are simultaneously dried at a drying temperature of 100 ° C. for 2 minutes, and the resin part (X) and the particle part ( A pressure-sensitive adhesive sheet with a substrate having a resin layer having a thickness shown in Table 4 was prepared.

Example 17
Manufactured on a release agent layer of a release film (product of Lintec Co., Ltd., product name “SP-PET381031”, thickness 38 μm, provided with a silicone release agent layer on one side of a PET film) as a first release material The resin composition solution (x-3) prepared in Example x-3, the coating solution (y-5) for forming a coating film (y ′) prepared in Production Example y-5, and Production Example x-3 The prepared resin composition solution (x-3) was simultaneously applied in this order using a multilayer die coater (width: 250 mm) at the flow rates and application speeds shown in Table 4, and the coating film (xβ '), A coating film (y') and a coating film (xα ') were simultaneously formed in this order.
The three-layer coating film (xβ ′), the coating film (y ′), and the coating film (xα ′) are simultaneously dried at a drying temperature of 100 ° C. for 2 minutes, and the resin part (X) and the particle part ( Y) and a resin layer having a thickness shown in Table 4 was formed. Then, on the surface (α) of the formed resin layer, the surface of the release material layer of a release film (product name “SP-PET386060” manufactured by Lintec Corporation) as the second release material is bonded. To produce an adhesive sheet without a substrate.
Then, after leaving this adhesive sheet without a substrate in a 23 ° C. environment for one week, the first release material is removed, and the surface (β) of the exposed resin layer and the aluminum vapor deposition layer as the substrate are formed. The provided PET film (Lintec Co., Ltd., product name “FNS Poppy N50”, thickness 50 μm) was laminated with the surface of the aluminum vapor-deposited layer so as to bond together, thereby preparing a pressure-sensitive adhesive sheet with a substrate.

Example 18
A 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 PET film, the resin composition solution (x-1) prepared in Production Example x-1 was applied using a knife coater to form a coating film (xβ ′). And it was made to dry for 2 minutes at the drying temperature of 100 degreeC, and the 8-micrometer-thick layer (X (beta)) containing the resin part (X) was formed. Furthermore, the surface of the formed layer (Xβ) and a release film of a release film (product name “SP-PET 381031”, manufactured by Lintec Corporation, PET film with a silicone release agent layer on one side, thickness 38 μm) The laminate was laminated so as to be bonded to the surface, and a laminate having a layer (Xβ) was once produced.
Next, on the surface of the layer (Xβ) exposed by peeling off the release film of the laminate, a coating solution (y ′) for forming a coating film (y ′) prepared in Production Example y-1, The resin composition solution (x-1) prepared in Production Example x-1 was simultaneously applied in this order with a multilayer die coater (width: 500 mm) at the flow rate and application speed shown in Table 4, and the layer (Xβ) From the side, the coating film (y ′) and the coating film (xα ′) were simultaneously laminated in this order.
Then, the two-layer coating films (y ′) and (xα ′) are simultaneously dried at a drying temperature of 100 ° C. for 2 minutes to include the resin part (X) and the particle part (Y). A pressure-sensitive adhesive sheet with a base material having a resin layer having the thickness shown was produced.

The following measurements or observations were made on the resin layers of each pressure-sensitive adhesive sheet prepared in Examples and Comparative Examples. These results are shown in Tables 3 and 4.

<Shape of recess on surface (α)>
Whether or not a recess satisfying the following requirements (I) to (II) is formed in the specific region defined by each requirement on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Examples and Comparative Examples. The observation was performed using a scanning electron microscope (manufactured by Hitachi, Ltd., product name “S-4700”, requirement (II) was observed at a magnification of 30 times).
In Tables 3 and 4, “A” is used when it is determined that a recess that satisfies each requirement is formed, and “F” when it is determined that there is no recess that satisfies each requirement. It is described.
Requirement (I): A plurality of concave portions having a height difference of 1.5 μm or more at the maximum exist in a region (P) surrounded by a square of 5 mm on an arbitrarily selected surface on the surface (α).
Requirement (II): Total number of a plurality of recesses having a height difference of at least 1.5 μm or more existing in a region (P) surrounded by a square of 5 mm on an arbitrarily selected side on the surface (α) (100 %), The number of recesses having different shapes is 95% or more (100%, that is, when all the recesses in the region (P) have different shapes, It is described as “A +” in the table).
In addition, among the values of the height difference of the plurality of concave portions measured at the time of the evaluation of the requirement (I), the largest value is described in Tables 3 and 4 as “maximum value of the height difference”.

<Area ratio occupied by recesses on the surface (α)>
Ten values calculated through the following operations (i) and (ii) are obtained, and the average value of these 10 values is expressed as “the area ratio occupied by the recesses on the surface (α)” of the target adhesive sheet. I saw it. The measurement results of each Example and Comparative Example are shown in Table 3 and Table 4.
Operation (i): As shown in FIG. 3 (a), an arbitrarily selected rectangle of 200 μm in length × 283.6 μm in width on the surface (α) of the resin layer included in the pressure-sensitive adhesive sheets prepared in Examples and Comparative Examples. The enclosed region (Q) was photographed using a laser microscope (manufactured by Keyence Corporation, product name “Laser Microscope VK-9700”), and a three-dimensional image of the selected region (Q) was obtained.
Operation (ii): As shown in FIG. 3 (b), based on the three-dimensional image obtained in the above operation (i), whether or not it corresponds to a portion occupied by a recess having a maximum height difference of 1.5 μm or more Thus, a binarized image of the region (Q) subjected to image processing (binarization processing) was obtained. Next, the area S occupied by the concave portion in the binarized image of the region (Q) is obtained using image analysis software (product name “Image-Pro Plus” manufactured by Media Cybernetics). Then, based on the calculation formula “[area ratio (%)] = S / total area of selected region (Q) × 100”, the area ratio occupied by the recesses in the selected region (Q) was calculated.

<Mass retention rate of resin layer of adhesive sheet>
In Examples and Comparative Examples other than Example 17, a release film (product name “SP-PET 381031” manufactured by Lintec Corporation, a PET film provided with a silicone release agent layer on one side, instead of the above-described base material, After the resin layer was formed on the surface of the release agent layer having a thickness of 38 μm according to the methods of Examples and Comparative Examples, the release film was removed to obtain a single resin layer.
Moreover, about Example 17, the 2 release film of the base materialless adhesive sheet produced in the middle was removed, and the resin layer simple substance was obtained.
Then, after measuring the mass of the resin layer before heating, the resin layer was put in a muffle furnace (product name “KDF-P90” manufactured by Denken) and heated at 800 ° C. for 30 minutes. And the mass of the resin layer after a heating was measured and the mass retention of the resin layer was computed by the following formula.
Mass retention of resin layer (%) = [mass of resin layer after heating] / [mass of resin layer before heating] × 100

For each pressure-sensitive adhesive sheet prepared in Examples and Comparative Examples, “air bleeding property”, “blister resistance”, and “adhesive strength” were measured or evaluated based on the following methods. These results are shown in Tables 3 and 4.

<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.

<Blister resistance>
Adhesive sheet with base material measuring 50 mm long × 50 mm wide is affixed to a polymethyl methacrylate plate (product name “Acrylite L001”, manufactured by Mitsubishi Rayon Co., Ltd.) 70 mm long × 150 mm wide × 2 mm thick. A test sample was prepared by pressure bonding using
This test sample was allowed to stand at 23 ° C. for 12 hours, then left in an 80 ° C. hot air dryer for 1.5 hours, and further left in a 90 ° C. hot air dryer for 1.5 hours, after heating was promoted. The blister generation state was visually observed, and the blister resistance of each pressure-sensitive adhesive sheet was evaluated according to the following criteria.
A: No blisters were confirmed.
B: A blister was partially confirmed.
C: Blister was confirmed on the entire surface.

<Adhesive strength>
After the adhesive sheet with a base material produced in Examples and Comparative Examples was cut into a size of 25 mm in length and 300 mm in width, the surface (α) of the resin layer of the adhesive sheet was 23 ° C. and 50% RH (relative humidity). Was attached to a stainless steel plate (SUS304, No. 360 polishing) and allowed to stand for 24 hours in the same environment. After standing, the adhesive force of each adhesive sheet was measured at a pulling speed of 300 mm / min by a 180 ° peeling method based on JIS Z0237: 2000.

According to Tables 3 and 4, the pressure-sensitive adhesive sheets produced in Examples 1 to 18 had a plurality of recesses that satisfy the requirements (I) to (II) on the surface (α), and the recesses on the surface (α) It was confirmed that the area ratio occupied belonged to the above-mentioned range, and all of air bleedability, blister resistance, and adhesive strength were good. In any of these pressure-sensitive adhesive sheets, the concave portions present on the surface (α) were also confirmed visually.
Further, in any of the pressure-sensitive adhesive sheets produced in Examples 1 to 18, a plurality of concave portions are irregularly present on the surface (α), and the shape of the pasting surface on the surface (α) is also irregular. It was confirmed to be regular. This can also be seen from FIGS.

4 and 5 are images when the pressure-sensitive adhesive sheets prepared in Examples 1 and 10 are observed with a scanning electron microscope, respectively, (a) is a cross-sectional image of the pressure-sensitive adhesive sheet, and (b) is the pressure-sensitive adhesive sheet. It is a perspective image of the surface ((alpha)) of the resin layer of a sheet | seat. In the image of FIG. 4 (a), the length of 20.0 μm is shown for the 10 scales shown in the lower right of the image, and in the image of FIG. 4 (b), the length is shown in the lower right of the image. The length of 1.00 mm is shown for 10 divisions. Further, in the image of FIG. 5A, the length of 200 μm is shown on the 10 scales shown in the lower right of the image, and in the image of FIG. 5B, 10 shown in the lower right of the image. The scale is 1.00 mm long.
From the images shown in FIGS. 4 and 5, a plurality of recesses are irregularly present on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet produced in Examples 1 and 10, and the surface (α ) It can be seen that the shape of the pasting surface is irregular.
The images in FIGS. 4 and 5 show the shape of the recesses present on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet produced in Examples 1 and 10, but the pressure-sensitive adhesive sheets of other examples The cross-sectional shape of the recess, the shape of the recess observed from the surface (α) side of the resin layer, and the shape of the pasting surface were also the same as the images shown in FIGS.

FIG. 6A shows a three-dimensional image obtained by observing an arbitrarily selected region (Q) on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet produced in Example 1 using a laser microscope. It is. Further, FIG. 6B shows image processing (binarization) depending on whether or not it corresponds to a portion occupied by a concave portion having a height difference of 1.5 μm or more based on the three-dimensional image of FIG. It is a binarized image of the region (Q) obtained by performing (processing). In addition, the gray part (part other than black) of FIG.6 (b) shows the part which the said recessed part occupies.

On the other hand, the formation of specific recesses was not observed on the surface of the resin layer included in the pressure-sensitive adhesive sheets prepared in Comparative Examples 1 and 2, resulting in poor air release properties. Further, the pressure-sensitive adhesive sheet of Comparative Example 1 was inferior in blister resistance.

FIG. 7 is an image when the pressure-sensitive adhesive sheet produced in Comparative Example 1 is observed with a scanning electron microscope, where (a) is a cross-sectional image of the pressure-sensitive adhesive sheet, and (b) is the surface of the resin layer of the pressure-sensitive adhesive sheet. It is a perspective image of ((alpha)). In the image of FIG. 7A, the length of 20.0 μm is shown for the 10 scales shown in the lower right in the image, and in the image of FIG. 7B, the length is shown in the lower right of the image. The length of 1.00 mm is shown for 10 divisions.
FIG. 8A shows a three-dimensional image obtained by observing an arbitrarily selected region (Q) on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet prepared in Comparative Example 1 using a laser microscope. It is. 8B is based on the three-dimensional image of FIG. 8A, image processing (binarization) depends on whether or not it corresponds to a portion occupied by a recess having a height difference of 1.5 μm or more at maximum. It is a binarized image of the region (Q) obtained by performing (processing).
As shown in the images of FIGS. 7 and 8, no concave portion was found on the surface (α) of the resin layer of the pressure-sensitive adhesive sheet produced in Comparative Example 1. Therefore, the binarized image for Comparative Example 1 in FIG. 8B is an image occupied by the black portion.

The pressure-sensitive adhesive sheet of one embodiment of the present invention is useful as a pressure-sensitive adhesive sheet having a large affixing area used for identification or decoration, for coating masking, for surface protection of metal plates and the like.

1a, 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, 131, 132

Recess

14, 14a Release material 50 200 μm long × 283.6 μm rectangular

Claims

A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
A plurality of concave portions having a height difference of 1.5 μm or more exist in the region (P) surrounded by a square with a side of 5 mm arbitrarily selected on the surface (α), and exist in the region (P). In the pressure-sensitive adhesive sheet, 95% or more of the plurality of recesses have shapes different from each other, and the area ratio of the recesses on the surface (α) is 16 to 95%.
The pressure-sensitive adhesive sheet according to claim 1, wherein the plurality of recesses are irregularly present on the surface (α).
The pressure-sensitive adhesive sheet according to claim 1 or 2, wherein the shape of the pasting surface on the surface (α) of the resin layer is indefinite.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the resin contained in the resin portion (X) includes a pressure-sensitive adhesive resin.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the resin contained in the resin portion (X) contains a resin having a functional group.
The pressure-sensitive adhesive sheet according to claim 5, wherein the resin having a functional group is an acrylic resin having a functional group.
The pressure-sensitive adhesive sheet according to claim 5 or 6, wherein the functional group is a carboxy group.
The pressure-sensitive adhesive sheet according to any one of claims 5 to 7, wherein the resin part (X) further contains one or more selected from a metal chelate crosslinking agent, an epoxy crosslinking agent, and an aziridine crosslinking agent.
The pressure-sensitive adhesive sheet according to any one of claims 5 to 8, wherein the resin part (X) contains both a metal chelate crosslinking agent and an epoxy crosslinking agent.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 9, wherein the fine particles are at least one selected from silica particles, metal oxide particles, and smectites.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 10, wherein the surface (β) of the resin layer on the side on which the base material or release material is provided has adhesiveness.
The pressure-sensitive adhesive sheet according to claim 11, comprising the resin layer on the release material.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 12, wherein a mass retention after heating the resin layer at 800 ° C for 30 minutes is 3 to 90 mass%.
The pressure-sensitive adhesive sheet according to any one of claims 1 to 13, wherein the concave portion is not formed by transferring an emboss pattern.
From the side on which the base material or release material is provided, the resin layer mainly includes a layer (Xβ) containing a resin part (X), a layer (Y1) containing 15% by mass or more of a particle part (Y), and mainly The pressure-sensitive adhesive sheet according to any one of claims 1 to 14, which has a multilayer structure in which layers (Xα) containing a resin portion (X) are laminated in this order.
The layer (Xβ) is a layer formed from a composition (xβ) containing a resin as a main component,
The layer (Y1) is a layer formed from a composition (y) containing 15% by mass or more of fine particles,
The pressure-sensitive adhesive sheet according to claim 15, wherein the layer (Xα) is a layer formed from a composition (xα) containing a resin as a main component.
The method for producing a pressure-sensitive adhesive sheet according to any one of claims 1 to 14, comprising at least the following steps (1) and (2).
Step (1): Forming a coating film (x ′) composed of a composition (x) containing a resin as a main component and a coating film (y ′) composed of a composition (y) containing 15% by mass or more of the fine particles. Step (2): A step of simultaneously drying the coating film (x ′) and the coating film (y ′) formed in the step (1).
It is a method of manufacturing the adhesive sheet of Claim 16, Comprising: The manufacturing method of an adhesive sheet which has the following process (1A) and (2A) at least.
Step (1A): a coating film (xβ ′) made of a composition (xβ) containing a resin as a main component on a substrate or a release material, and a coating film made of a composition (y) containing 15% by mass or more of the fine particles. (Y ′) and a coating film (xα ′) made of a composition (xα) containing a resin as a main component is laminated and formed in this order. Step (2A): Coating film formed in step (1A) ( xβ ′), coating film (y ′), and coating film (xα ′) are simultaneously dried.
It is a method of manufacturing the adhesive sheet of Claim 16, Comprising: The manufacturing method of an adhesive sheet which has the following process (1B) and (2B) at least.
Step (1B): a coating film comprising a composition (y) containing 15% by mass or more of the fine particles on a layer (Xβ) mainly containing a resin portion (X) provided on a substrate or a release material ( Step (2B): A coating film (y) formed by laminating and forming a coating film (xα ′) made of a composition (xα) containing a resin as a main component in this order (y ′) ') And the step of simultaneously drying the coating film (xα')
A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
A pressure-sensitive adhesive sheet, wherein a concave portion exists on the surface (α) and an area ratio of the concave portion on the surface (α) is 16 to 95%.
A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
There are a plurality of recesses having a height difference of 1.5 μm or more in the region (P) arbitrarily selected on the surface (α) surrounded by a square with a side of 5 mm, and the recesses on the surface (α) A pressure-sensitive adhesive sheet having an area ratio of 16 to 95%.
A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
On the surface (α), a plurality of recesses are present irregularly,
The pressure-sensitive adhesive sheet, wherein the area ratio of the concave portion on the surface (α) is 16 to 95%.
A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
There are recesses on the surface (α), and the area ratio of the recesses on the surface (α) is 16 to 95%,
The adhesive sheet whose shape of the sticking surface on the surface ((alpha)) is indefinite.
A side having a resin layer containing a resin part (X) containing a resin as a main component and a particle part (Y) made of fine particles on at least a base material or a release material, on which the base material or the release material is provided The surface (α) of the resin layer on the opposite side to the adhesive sheet having adhesiveness,
There are recesses on the surface (α), and the area ratio of the recesses on the surface (α) is 16 to 95%,
The pressure-sensitive adhesive sheet, wherein the concave portion is not formed by transferring an emboss pattern.