JP2023031976A - Manufacturing method of adhesive-coated sheet and adhesive-coated sheet - Google Patents

Abstract

To provide a manufacturing method of an adhesive-coated sheet facilitating a coating defect detection when coating an adhesive layer to a release sheet, and also to provide an adhesive-coated sheet.SOLUTION: A manufacturing method is for an adhesive-coated sheet including a sheet member, an adhesive layer and a release sheet. The release sheet includes a release substrate sheet. The manufacturing method includes: an adhesive layer formation process of coating one surface of the release sheet with an adhesive agent and then drying or curing the adhesive agent so as to form an adhesive layer on the release sheet; and a sheet member lamination process of laminating the adhesive layer and the sheet member so as to face each other. The adhesive layer formation process includes an adhesive agent appearance confirmation process of confirming a coating appearance of the adhesive agent coated on the release sheet.SELECTED DRAWING: Figure 2

Description

TECHNICAL FIELD The present disclosure relates to a method for producing an adhesive sheet and an adhesive sheet.

In the production of an adhesive-attached sheet in which an adhesive is applied to a sheet member, the following problems arise when the adhesive containing a solvent or dispersant is applied to the sheet member. When the sheet member is a thermoplastic resin film or the like, the solvent for the adhesive or the organic solvent contained in the dispersant may cause problems such as dissolution, swelling, deformation, and whitening of the sheet member. In addition, when water is used as the main component of the solvent or dispersant to avoid organic solvents, the sheet member is heated to 100° C. or higher for drying, which causes discoloration in the pattern layer of the sheet member. In some cases, defects such as deformation (wrinkles) due to heating may occur. That is, when applying an adhesive to a sheet member, the main component of the solvent or dispersant for the adhesive may be an organic solvent or water. Malfunction may occur.
As a countermeasure for the above problems, there is a method of manufacturing an adhesive sheet by applying an adhesive to the release sheet of the adhesive sheet and then bonding the adhesive layer on the release sheet to the sheet member. It is known (Patent Document 1).

JP 2019-151816 A

As in Patent Document 1, in the case of a manufacturing method in which an adhesive is applied to a release sheet related to an adhesive-attached sheet, the release sheet is peeled off in the step of attaching to the adherend and is finally adhered. It does not remain on the body. Therefore, regardless of the performance and design to be imparted to the adherend, the material of the release sheet should be suitable for releasability from the pressure-sensitive adhesive, durability against the solvent and dispersion medium in the pressure-sensitive adhesive, and The optimum material can be selected by considering only the heat resistance during heating when the solvent or dispersion medium is dried. Therefore, it is possible to prevent the above problems related to the adhesive-attached sheet, but there are the following problems. The color of the adhesive is usually white in many cases, but the color of the side of the release sheet on which the adhesive layer is coated is often white or a color close to it. Since the color of the coated surface of the release sheet and the color of the coated surface of the release sheet are often the same color, there is a problem that it is difficult to visually recognize defects related to the coating of the adhesive. Due to this problem, there is a risk that many defective coating products may be manufactured before the coating defects are noticed, which is a problem.

The present disclosure has been made in view of the above problems, and an object of the present disclosure is to provide a method for manufacturing an adhesive-attached sheet that facilitates detection of coating defects when coating an adhesive layer on a release sheet, and an adhesive-attached sheet. It is to provide a sheet.

The method for producing a pressure-sensitive adhesive sheet of the present disclosure is a method for producing a pressure-sensitive adhesive sheet including a sheet member, an adhesive layer, and a release sheet, the release sheet including a release base sheet, and one side of the release sheet. A pressure-sensitive adhesive layer forming step of applying a pressure-sensitive adhesive to the surface and then drying or curing to form a pressure-sensitive adhesive layer on the release sheet; The pressure-sensitive adhesive layer forming step includes a pressure-sensitive adhesive appearance confirmation step of checking the coating appearance of the pressure-sensitive adhesive applied to the release sheet.

In the method for producing a pressure-sensitive adhesive sheet, the release sheet further includes a release layer, the release layer is provided on one side surface of the release sheet, and in the pressure-sensitive adhesive layer forming step, the pressure-sensitive adhesive is added to the release layer. Layers may be coated.

In the method for producing a pressure-sensitive adhesive sheet, a color difference ΔE ^* between one surface of the release sheet and the pressure-sensitive adhesive layer may be 4 or more.
Here, in the L ^* a ^* b ^* color system defined in JIS Z8729, the color of the pressure-sensitive adhesive layer is L ^* _1a ^* _1b ^* ₁ , and the color of the surface of the release sheet on the release layer side is L ^* ₂ . Assuming a ^* _2b ^* ₂ ,
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2
ΔL ^* =L ^* ₂ -L ^* ₁
Δa ^* = a ^* ₂ - a ^* ₁
Δb ^* =b ^* ₂ -b ^* ₁

In the method for producing a pressure-sensitive adhesive sheet, the difference ΔV between the brightness of one side surface of the release sheet and the brightness of the adhesive layer may be 4 or more with respect to the brightness V specified in JIS Z8721.

In the method for producing a pressure-sensitive adhesive sheet, the difference ΔH between the hue of one surface of the release sheet and the hue of the pressure-sensitive adhesive layer may be 4 or more with respect to hue H defined in JIS Z8721.

In the method for producing a pressure-sensitive adhesive sheet, the difference ΔC between the saturation of one side of the release sheet and the saturation of the adhesive layer may be 4 or more with respect to the saturation C specified in JIS Z8721. .

In the method for producing a sheet with an adhesive, the brightness V defined in JIS Z8721 may be 7 or more.

In the method for producing a sheet with adhesive, the adhesive layer may contain an acrylic resin and be porous.

The adhesive-attached sheet of the present disclosure is an adhesive-attached sheet including a sheet member, an adhesive layer, and a release sheet, the release sheet including a release base sheet, one side of the release sheet and the adhesive layer. is a pressure-sensitive adhesive sheet having a color difference ΔE ^* of 4 or more.
Here, in the L ^* a ^* b ^* color system defined in JIS Z8729, the color of the pressure-sensitive adhesive layer is L ^* _1a ^* _1b ^* ₁ , and the color of one side of the release sheet is L ^* _2a . ^* ₂ b ^* ₂ , then
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2
ΔL ^* =L ^* ₂ -L ^* ₁
Δa ^* = a ^* ₂ - a ^* ₁
Δb ^* =b ^* ₂ -b ^* ₁

Advantageous Effects of Invention According to the present disclosure, it is possible to provide a method for manufacturing an adhesive-attached sheet and an adhesive-attached sheet that facilitate detection of coating defects when an adhesive layer is applied to a release sheet.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic cross-sectional view for explaining the layer structure of the adhesive-attached sheet of the present disclosure; FIG. 4 is a schematic cross-sectional view for explaining the method for manufacturing the pressure-sensitive adhesive sheet of the present disclosure; 1 shows an example of coating failure of an adhesive layer during production of an adhesive-attached sheet of the present disclosure;

The adhesive-attached sheet and its manufacturing method will be described in detail below with reference to the drawings.
In the following description, specific numerical values, shapes, materials, etc. are shown and described, but these can be changed as appropriate.
In this specification, terms such as plate, sheet, and film are used, and as a general usage, they are used in the order of thickness, plate, sheet, and film. I use it in my book as well. Plates, sheets, films, etc. may be used to form the layers. However, such proper use has no technical meaning, so even if these words are appropriately replaced, the essence of the present disclosure and the interpretation of the scope of claims remain unchanged. In the present disclosure, the term "sheet" is used in a broad sense to include so-called plates, sheets, and thick forms commonly referred to as films.

Further, the term "surface" refers to a surface that coincides with the planar direction of the target sheet-like member when the target sheet-like member is viewed as a whole and from a broad perspective. The normal direction used for a sheet-like member refers to the normal direction to the surface of the member. Terms such as "parallel" and "perpendicular" and length and angle values used herein to specify shapes and geometric conditions and their degrees are not bound by a strict meaning. , to include the extent to which similar functions can be expected.
In addition, although the terms "front" and "back" are used in this specification, there is no technical meaning to distinguish between the front and back. . In the present specification, the decorative sheet is described as the front side, which is the normal observation side when the decorative sheet is used, and the back side, which is the opposite side.

Furthermore, in this specification, when multiple upper limit candidates and multiple lower limit candidates are given for a parameter, the numerical range of the parameter is any one upper limit candidate and any one It may be configured by combining the lower limit value candidates. For example, "Parameter B is, for example, A1 or more, may be A2 or more, or may be A3 or more. Parameter B may be, for example, A4 or less, may be A5 or less, or A6 or less. There may be.” In this case, the numerical range of the parameter B may be A1 or more and A4 or less, A1 or more and A5 or less, A1 or more and A6 or less, or A2 or more and A4 or less, It may be A2 or more and A5 or less, A2 or more and A6 or less, A3 or more and A4 or less, A3 or more and A5 or less, or A3 or more and A6 or less.

[Adhesive sheet]
An embodiment of the present disclosure will be described below with reference to FIG. Each drawing shown below is a schematic drawing, and the size, shape, thickness, decoration, etc. of each part are appropriately exaggerated or simplified for easy understanding. Configurations that are not directly related to the description are omitted as appropriate. In addition, in each figure below, the same reference numerals are assigned to the same parts, and some detailed explanations may be omitted.

FIG. 1 is a schematic cross-sectional view illustrating the layer structure of a pressure-sensitive adhesive-attached sheet 1 according to the present disclosure. The adhesive-attached sheet 1 includes a sheet member 10 , an adhesive layer 20 and a release sheet 30 . The release sheet 30 includes a release base sheet 31 having at least one side surface (which may be referred to as a release surface) that is releasable from the pressure-sensitive adhesive layer 20 .
When one side of the release base sheet 31 has an appropriate releasability, the release sheet 30 is composed of a single layer of only the release base sheet 31, and the one side of the release base sheet 31 is It becomes a peeling surface (this form is omitted from the drawing because it is simple).
On the other hand, when both the front and back surfaces of the release base sheet 31 do not have sufficient releasability from the adhesive layer 20, as shown in FIG. A release layer 32 whose surface has an appropriate release property with respect to the pressure-sensitive adhesive layer 20 is laminated by coating or bonding. In this embodiment, the surface of the release layer 32 laminated on one surface of the release substrate sheet 31, which is opposite to the release substrate sheet 31 side, is one surface of the release sheet 30, and It becomes the release surface.
FIG. 1 shows a form in which the release sheet 30 has a release layer 32. In the figure, a release base sheet 31, a release layer 32, an adhesive layer 20, and a sheet member 10 are laminated in this order from the bottom. It is
In the layer structure of the adhesive-attached sheet 1 according to the present disclosure, all layers except for the release sheet 30 and the adhesive layer 20 are included in the sheet member 10 .
Each configuration of the adhesive-attached sheet 1 will be described below.

(seat member)
The seat member 10 can take various forms. However, as described below, the present disclosure relates to the relationship between the adhesive layer 20 and the release sheet 30, so the form of the sheet member 10 is arbitrary. The adhesive-attached sheet 1 is usually used by attaching the sheet member 10 to an adherend such as a wall surface by pressing the adhesive layer 20 exposed by removing the release sheet 30 against an adherend such as a wall surface. Therefore, in the state of use, of the two surfaces of the sheet member 10, the surface opposite to the surface in contact with the pressure-sensitive adhesive layer 20 is exposed. When the adhesive-attached sheet 1 is used, the sheet member 10 is a main body portion that realizes the function of the adhesive-attached sheet 1 .

Sheet member 10 generally includes a base sheet 11 . The base sheet 11 plays a role of ensuring at least strength in the sheet member 10 . The sheet member 10 may be composed of the base sheet 11 only. Examples of materials for the base sheet 11 include fibrous base materials. Examples of the fibrous base material include known materials used for the adhesive sheet 1, such as paper, nonwoven fabric, woven fabric, and various resins. The paper may be general paper or flame-retardant paper.

Flame-retardant paper is ordinary paper containing a flame retardant. Examples of flame retardants include nitrogen compounds such as urea and ammonium compounds; hydroxides (preferably hydrates) such as magnesium hydroxide and aluminum hydroxide; flame retardants containing self-extinguishing phosphorus or halogen elements. be done. Among them, a compound containing water of crystallization, such as magnesium hydroxide, can be made flame-retardant by the heat of vaporization of the water of crystallization during combustion decomposition.
The nonwoven fabric may be a wet nonwoven fabric such as a papermaking type, or a dry nonwoven fabric such as an adhesive type, a mechanical bonding type (needle punch, stitch bond), or a spunbond type. Specific examples of nonwoven fabrics include resin fiber nonwoven fabrics such as rayon paper, pulp mixed nonwoven fabric, Japanese paper, glass nonwoven fabric, asbestos nonwoven fabric, polyester nonwoven fabric, and polycarbonate nonwoven fabric.
Examples of the resin, that is, the resin sheet include thermoplastic resin films such as acrylic resin films, vinyl chloride resin films, and olefin resin films (polyethylene, polypropylene, etc.). Preferred examples of the resin sheet include biaxially stretched polyethylene terephthalate (PET) film and polypropylene film.

The sheet member 10 usually includes a layer having some function in addition to the base sheet 11 . The layer having some function is typically a pattern layer 12 having a function of imparting design to the pressure-sensitive adhesive sheet 1 . The pattern layer 12 is usually formed by applying (typically printing) single-color or multi-color ink, and the designed pattern is applied to exhibit design.

The pattern layer 12 preferably contains, for example, a resin and a colorant.
The resin (binder resin) contained in the pattern layer 12 includes various polyester resins, vinyl chloride resins such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate-maleic acid copolymer, and poly(meth)acrylic. Methyl acid, polybutyl (meth)acrylate, methyl (meth)acrylate-butyl (meth)acrylate copolymer, styrene-methyl (meth)acrylate copolymer, styrene-methyl (meth)acrylate-( It is also possible to use acrylic resins of 2-hydroxyethyl methacrylate copolymers, two-liquid curable urethane resins containing a polyol compound as a main component and an isocyanate compound as a curing agent, chlorinated polypropylene, and the like. The above resins may be used alone or in combination of two or more. It is preferable to add a cross-linking agent, a polymerization initiator, or a polymerization accelerator to the resin to improve the coating film strength and durability.

The coloring agent (dye or pigment) contained in the pattern layer 12 is dissolved (or dispersed) in the resin in the ink state before drying (curing). Therefore, the pattern layer 12 in which the ink is dried (cured) contains a coloring agent. Examples of coloring agents include inorganic pigments, organic pigments, metal powder pigments, pearl luster pigments, fluorescent pigments, and luminous pigments. For example, inorganic pigments include carbon black, black iron oxide, titanium white, zinc white, red iron oxide, Prussian blue, yellow lead, cadmium red, etc. Organic pigments include azomethine azo black pigments, perylene black pigments, and various hues. chromatic azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, nickel-azo complexes, dioxazine pigments, etc.; and, as pearlescent pigments, scale-like foil pieces such as titanium oxide-coated mica and bismuth oxide chloride can be mentioned. These colorants may be used alone or in combination of two or more, or may be used together with fillers such as silica, extender pigments such as organic beads, neutralizers, surfactants, and the like.

Moreover, as a method of imparting designability without relying on ink, that is, coloring, there is a method of imparting designability by surface unevenness, typically embossing. A design property may be obtained by applying a thermoplastic resin or the like and pressing an embossing plate against the surface of the thermoplastic resin or the like to form an uneven pattern on the surface of the thermoplastic resin or the like. A layer of a thermoplastic resin or the like having an uneven pattern on its surface is sometimes called an embossed layer. In the case of imparting a design property by surface unevenness, an uneven pattern may be formed on the surface of the base sheet 11 by pressing an embossing plate against the surface of the base sheet 11 regardless of the embossed layer. Such a case is sometimes called embossing. Also, both the pattern layer 12 and the embossed layer may be applied.

The sheet member 10 may include layers other than the base sheet 11, the pattern layer 12, and the embossed layer. Other layers include a surface protective layer, an adhesive layer, a primer layer, and the like.
The surface protective layer is a layer positioned on the outermost surface of the sheet member 10 on the side opposite to the side facing the pressure-sensitive adhesive layer 20 and having a function of protecting the surface of the pressure-sensitive adhesive sheet 1 . The adhesive layer is a layer having the function of bonding the two layers in contact with each other. The primer layer is a layer related to a so-called base treatment, and is a layer having a function of enhancing adhesion between layers in contact with the front and back of the primer layer, for example.
The sheet member 10 may include layers other than the layers exemplified above, and may include a plurality of layers.

(Adhesive layer)
Next, the adhesive layer 20 will be explained. In the adhesive sheet 1 , the adhesive layer 20 is provided between the release sheet 30 and the sheet member 10 . The adhesive layer 20 is formed by curing (drying) a liquid adhesive 20s.
As described above, the adhesive-attached sheet 1 is usually used by attaching the sheet member 10 to an adherend such as a wall surface by pressing the exposed adhesive layer 20 by removing the release sheet 30 against the adherend. . When the adhesive-attached sheet 1 is used, the adhesive layer 20 is a layer having a function of bonding the adherend and the sheet member 10 together.

The adhesive 20s contains a solvent or dispersant, and examples of the solvent or dispersant include water, organic solvents, or both. That is, the adhesive 20s contains at least one of water and an organic solvent. Examples of organic solvents include isopropyl alcohol, methyl ethyl ketone, ethyl acetate, and ethyl alcohol.

Examples of the adhesive 20s include, for example, a liquid resin composition (acrylic emulsion) disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2017-36404), particularly a one-liquid curable acrylic resin. It is preferable to consist of If it is a one-liquid curing type, it is less likely to cause problems such as hardening in a warm environment and an increase in adhesive strength, which makes it difficult to peel off, and that an adhesive residue occurs when peeled off. In addition, since acrylic resin does not contain chlorine atoms, basically only carbon dioxide and water are emitted even if it is incinerated at the time of disposal, which is advantageous from an environmental point of view.

Further, the adhesive 20s (adhesive layer 20) may be colored. The case where it is better to be colored and the effects in that case will be described later, but this is a purpose different from the improvement of designability. When the adhesive 20s (adhesive layer 20) is colored, the adhesive 20s contains a coloring agent.
The colorant (dye or pigment) contained in the adhesive layer 20 is dissolved or dispersed in the solvent or dispersant in the state of the adhesive 20s.
Examples of coloring agents include inorganic pigments, organic pigments, metal powder pigments, pearl luster pigments, fluorescent pigments, and luminous pigments. For example, inorganic pigments include carbon black, black iron oxide, titanium white, zinc white, red iron oxide, Prussian blue, yellow lead, cadmium red, etc. Organic pigments include azomethine azo black pigments, perylene black pigments, and various hues. chromatic azo pigments, lake pigments, anthraquinone pigments, quinacridone pigments, phthalocyanine pigments, isoindolinone pigments, nickel-azo complexes, dioxazine pigments, etc.; and, as pearlescent pigments, scale-like foil pieces such as titanium oxide-coated mica and bismuth oxide chloride can be mentioned. These colorants may be used alone or in combination of two or more, or may be used together with fillers such as silica, extender pigments such as organic beads, neutralizers, surfactants, and the like.

If the adhesive 20s contains water, it needs to be heated to 100° C. or higher when drying the adhesive 20s. When the adhesive layer 20 is formed by applying the adhesive 20s to the sheet member 10 and then drying the sheet member 10, the sheet member 10 is also exposed to a high temperature of 100° C. or higher for drying the adhesive 20s. It will happen. In this case, the sheet member 10 may be damaged by heat, which is not preferable.

On the other hand, in the case where the adhesive 20s contains an organic solvent, if a method of applying the adhesive 20s to the sheet member 10 and then drying the sheet member 10 is adopted, when the base sheet 11 related to the sheet member 10 is a resin sheet, , the base sheet 11 may swell, melt, or bleed due to the organic solvent, which is also not preferable.

Therefore, the pressure-sensitive adhesive sheet 1 according to the present disclosure has one surface of the release sheet 30 (when the release sheet 30 has a release layer 32, the release layer 32 on the release base sheet 31 side). The sheet member 10 is laminated on the adhesive layer 20 after the adhesive 20 s is applied to the opposite surface) and then dried to form the adhesive layer 20 . This will be discussed later.

(Release sheet)
Next, the release sheet 30 will be described. The release sheet 30 plays a role of protecting the adhesive layer 20 so that the adhesive layer 20 does not come into contact with other objects until the adhesive-attached sheet 1 is used, that is, until it is attached to an adherend. layer. When using the adhesive-attached sheet 1, that is, when attaching the adhesive-attached sheet 1 to an adherend, the release sheet 30 is peeled off from the adhesive-attached sheet 1 to expose the adhesive layer 20, and the exposed adhesive is removed. The agent layer 20 is attached to the adherend.
The release sheet 30 is composed of at least a release base sheet 31, but practically, as shown in FIG. In many cases, a laminated body structure including a release base sheet 31 and a release layer 32, which has a large degree of freedom to be used, is used. Hereinafter, as the configuration of the release sheet 30, the configuration of the release layer 32 will be described as an example.
One surface (release surface) of the release layer 32 is in direct contact with the pressure-sensitive adhesive layer 20, and the release base sheet 31 is laminated on the other surface side.

The release layer 32 has a function of smoothly releasing the adhesive layer 20 and the release sheet 30 in the adhesive sheet 1 . That is, the release layer 32 is designed to have strong adhesion to the release base sheet 31 and weak adhesion to the pressure-sensitive adhesive layer 20 . The material for such a release layer 32 is not particularly limited as long as it is a material having releasability with respect to the adhesive layer 20. Examples include silicone resins such as silicon acrylate and polysiloxane, and organic resin-modified silicone resins. , fluorine resins, aminoalkyd resins, melamine resins, acrylic resins, polyester resins, polyethylene, polypropylene, polymethylpentene and other olefin resins. These resins may be emulsion type, solvent type or non-solvent type.

The release base sheet 31 is the base of the release sheet 30 and is mainly responsible for strength. When the release base sheet 31 itself has the desired releasability, the release sheet 30 can be composed only of the release base sheet as described above. In general, it is often difficult to select a sheet material having sufficient releasability as a single layer for a specific pressure-sensitive adhesive layer. The release layer 32 is made to function as a release sheet 30 by coming into contact with the adhesive layer 20 . Materials for the release base sheet 31 include (1) paper such as woodfree paper, coated paper, kraft paper, linter paper, and impregnated paper, (2) polyester resin such as polyethylene terephthalate (PET), and olefin resin such as polypropylene and polyethylene. (3) a laminate of two or more types of paper exemplified in (1) above; (4) a laminate of two or more thermoplastic resin sheets exemplified in (2) above. , (5) a laminate of one or more types of paper exemplified in (1) above and one or more types of thermoplastic resin sheets exemplified in (2) above, and the like.

Based on the above, as the release sheet 30, for example, a silicone release type PET (polyethylene terephthalate) film, an untreated PET film, a PP film, a silicone release type paper, or the like can be used.
The release sheet 30 may be colored. The case where it is better to be colored and the effects in that case will be described later. In the present disclosure, that the release sheet 30 is colored means that when the release sheet 30 is observed from the release layer 32 side, it looks like it is colored. Examples of the form in which the release sheet 30 is colored include: (1) the release base sheet 31 containing a coloring agent (in the case where the release sheet 30 does not have the release layer 32, this form is used exclusively); ), (2) the release layer 32 contains a colorant, (3) both the release base sheet 31 and the release layer 32 contain the respective colorants, and (4) the separation between the release base sheet 31 and the release layer 32 For example, a layer containing a coloring agent such as a colored ink layer is laminated therebetween. The coloring agent is the same as those exemplified as the coloring agent contained in the adhesive layer 20 described above.

The adhesive-attached sheet 1 according to the present disclosure has been described above. The effects of the adhesive-attached sheet 1 will be described in the manufacturing method of the adhesive-attached sheet 1, which will be described later.

[Method for producing adhesive-attached sheet]
Next, a method for manufacturing the adhesive-attached sheet 1 according to the present disclosure will be described with reference to FIG. 2, which is a schematic cross-sectional view showing the layer structure. First, a release sheet 30 including a release layer 32 and a release base sheet 31 is prepared (FIG. 2(a)).
Of course, when one surface of the release base sheet has a releasability within an appropriate range with respect to the adhesive layer 20, the release layer 32 is omitted, and the release sheet 30 is composed only of the release base sheet 31. However, in the following description of the manufacturing method, the release sheet 30 having a configuration in which a release layer is laminated will be described as an example.
Next, an adhesive 20s (an adhesive bubble-containing composition 20sb to be described later) is applied to the release layer 32 of the release sheet 30 (FIG. 2(b)), and then dried or cured. A layer 20 is formed (adhesive layer forming step) (FIG. 2(c)). In the adhesive layer forming step, the coating appearance of the adhesive 20s applied to the release sheet 30 is checked (adhesive appearance checking step). Next, the sheet member 10 is prepared and laminated so that the adhesive layer 20 on the release sheet 30 and the surface of the sheet member 10 to be the adhesive layer 20 side face each other (sheet member lamination step), and the adhesive is Attached sheet 1 is obtained (Fig. 2(d)).
Each of the constituent elements is as described for the adhesive-attached sheet 1 .

According to the manufacturing method described above, the adhesive 20 s is applied not to the sheet member 10 but to the release sheet 30 . Therefore, the sheet member 10 is not exposed to a high temperature for drying or curing the adhesive 20s, so that the sheet member 10 can be prevented from being damaged by heat. Further, when the base sheet 11 of the sheet member 10 is a resin sheet and the adhesive 20s contains an organic solvent, the organic solvent may cause problems such as swelling, melting, bleeding, etc. of the base sheet 11. However, since the adhesive 20s is applied to the release sheet 30, the problem can be avoided.

The pressure-sensitive adhesive layer forming step and the pressure-sensitive adhesive appearance confirmation step will be described. When applying the adhesive 20s onto the release layer 32 of the release sheet 30, various coaters can be used. As a preferred example, the acrylic emulsion composition disclosed in Patent Document 2 for forming the pressure-sensitive adhesive 20s is placed in a stirrer, and the composition is stirred while nitrogen gas is mixed to create air bubbles in the composition. 20 sb (adhesive 20 s) of the adhesive bubble-containing composition is prepared (FIG. 2(e)). Next, an adhesive bubble-containing composition 20sb (adhesive 20s) is applied onto the release layer 32 of the release sheet 30 (FIG. 2(b)). For the coating, for example, a comma coater can be used, but other known coating methods may also be used.

After coating the adhesive bubble-containing composition 20sb on the release layer 32 of the release sheet 30, the adhesive bubble-containing composition 20sb is dried while being heated to form the adhesive layer 20 (drying step, FIG. 2 (c)). In the drying step, for example, a drying furnace with a temperature of about 60° C. to 140° C. can be used. As the drying time, for example, about 30 seconds to 10 minutes can be exemplified. Moreover, in the drying step, drying may be accelerated while blowing air to the pressure-sensitive adhesive bubble-containing composition 20sb. By performing the drying process, the pressure-sensitive adhesive layer 20 is formed in which the concave shapes 20a are formed on both sides of the pressure-sensitive adhesive bubble-containing composition 20sb. The recessed shape 20a is formed when the air bubbles contained in the adhesive air bubble-containing composition 20sb are broken and part of the shape of the air bubbles remains. Here, if the bubbles are broken in a state in which the adhesive bubble-containing composition 20sb is insufficiently cured, the concave shape 20a is less likely to remain. On the other hand, if the pressure-sensitive adhesive bubble-containing composition 20sb is cured before the bubbles are broken, there is a risk that the concave shape 20a will not be formed. Therefore, in order to form the concave shape 20a, it is desirable to perform the drying process under the condition that the bubbles are broken while the composition 20sb containing adhesive bubbles is cured to some extent. Therefore, the temperature and the amount of air blown in the drying process greatly affect the state of the concave shape 20a.

As described above as a preferred example, the pressure-sensitive adhesive layer 20 preferably contains an acrylic resin and is porous, that is, includes the concave shape 20a. Such an adhesive layer exerts adhesive strength to an adherend mainly because many concave shapes 20a formed on the surface of the adhesive layer 20 act as suction cups, unlike ordinary adhesive. The pressure-sensitive adhesive sheet 1 having such a pressure-sensitive adhesive layer 20 can be easily peeled off from the adherend surface without destroying the adherend surface and the pressure-sensitive adhesive layer 20, and can be easily re-adhered. . In other words, reworkability is good.

(Adhesive appearance confirmation process)
The pressure-sensitive adhesive layer forming step according to the present disclosure as described above includes a pressure-sensitive adhesive appearance confirmation step. That is, the coating appearance of the adhesive 20s coated on the release layer 32 of the release sheet 30 is confirmed. The pressure-sensitive adhesive appearance confirmation step may be performed before or after the drying or curing, but is preferably performed after the drying or curing. This is because the coating appearance of the pressure-sensitive adhesive layer 20 in a nearly completed state can be confirmed.
Further, the confirmation of the appearance of the coating may be confirmed visually by a person, or may be confirmed by an appearance inspection device (so-called machine vision). The inspection frequency may be intermittent inspection or 100% inspection, but 100% inspection is preferable.

It is preferable that the coating appearance of the adhesive 20s is easy to visually confirm whether the confirmation of the appearance in the adhesive layer forming step is done visually by a person or by an appearance inspection device. Specifically, it is preferable that the adhesive 20s (adhesive layer 20) to be coated is easily visible on the release layer 32 of the release sheet 30 to be coated. Typically, it is preferable that the color difference between the surface of the release sheet 30 on the release layer 32 side and the adhesive 20s (adhesive layer 20) is large.
As a method for increasing the difference in color between the release sheet 30 and the adhesive 20s (adhesive layer 20), both the release sheet 30 and the adhesive 20s (adhesive layer 20) may be colored. May be colored. Each coloring method is as described for the adhesive layer 20 and release sheet 30 above.
In the case of checking the coating appearance, if a light source is provided exclusively for checking the appearance, the color of the light source is a color that is complementary to the color of either the adhesive 20s (adhesive layer 20) or the release sheet 30. is preferably In this case, the difference in apparent color between the release sheet 30 and the adhesive 20s (adhesive layer 20) can be further increased, making confirmation easier.

To quantitatively express that the color difference is large, the color difference ΔE ^* between the surface of the release sheet 30 on the release layer 32 side and the pressure-sensitive adhesive layer 20 is preferably 4 or more. Here, in the L ^* a ^* b ^* color system defined in JIS Z8729, the color of the adhesive layer 20 is L ^* _1a ^* _1b ^* ₁ , and the color of the surface of the release sheet 30 on the release layer 32 side is Assuming L ^* ₂ a ^* ₂ b ^* ₂ ,
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2
ΔL ^* =L ^* ₂ -L ^* ₁
Δa ^* = a ^* ₂ - a ^* ₁
Δb ^* =b ^* ₂ -b ^* ₁
is.

As described above, when the color difference ΔE ^* between the surface of the release sheet 30 on the release layer 32 side and the adhesive layer 20 is 4 or more, the adhesive layer 20 (adhesive 20s) is easy to see. Therefore, it becomes easy to visually confirm coating defects of the adhesive 20s (adhesive layer 20) in the adhesive layer forming step. This is the same regardless of whether it is a visual confirmation by a person or a confirmation by an appearance inspection device. Therefore, it is possible to suppress the manufacturing of many defective coating products due to the delay in noticing coating defects.

Further, it is preferable that the difference ΔV between the brightness of the release layer 32 side of the release sheet 30 and the brightness of the adhesive layer 20 is 4 or more. Here, the brightness V is the brightness V specified in JIS Z8721. Even in this case, since the adhesive layer 20 (adhesive layer 20s) coated on the release layer 32 is easy to see due to the difference in brightness, the adhesive layer 20s (adhesive layer 20) in the adhesive layer forming step This makes it easy to visually confirm coating defects. Therefore, it is possible to suppress the manufacturing of many defective coating products due to the delay in noticing coating defects.

Further, it is preferable that the difference ΔH between the hue of the surface of the release sheet 30 on the side of the release layer 32 and the hue of the pressure-sensitive adhesive layer 20 is 4 or more. Here, the hue H is the hue H defined in JIS Z8721. Even in this case, since the adhesive layer 20 (adhesive 20s) coated on the release layer 32 is easy to see due to the difference in hue, the adhesive 20s (adhesive layer 20) in the adhesive layer forming step This makes it easy to visually confirm coating defects. Therefore, it is possible to suppress the manufacturing of many defective coating products due to the delay in noticing coating defects.

In addition, it is preferable that the difference ΔC between the saturation of the release layer 32 side of the release sheet 30 and the saturation of the adhesive layer 20 is 4 or more. Here, the saturation C is the saturation C defined in JIS Z8721. Even in this case, since the adhesive layer 20 (adhesive 20s) coated on the release layer 32 is easy to see due to the difference in saturation, the adhesive 20s (adhesive layer 20 ) makes it easy to visually confirm coating defects. Therefore, it is possible to suppress the manufacturing of many defective coating products due to the delay in noticing coating defects.

In the above, it is preferable that the pressure-sensitive adhesive layer 20 contains an acrylic resin and is porous, that is, includes the concave shape 20a. In this case, if the pressure-sensitive adhesive layer 20 is not particularly colored, it will appear white under normal white light due to irregular reflection due to its porosity. In this case, by coloring the release sheet 30 to increase the difference between the color of the surface of the release sheet 30 on the release layer 32 side and the color of the pressure-sensitive adhesive layer 20, the same effect as described above can be obtained. can.

Based on the above, the adhesive layer 20 preferably has a brightness V of 7 or more as defined in JIS Z8721. In this case, the pressure-sensitive adhesive layer 20 exhibits white under normal white light. Even when the pressure-sensitive adhesive layer 20 contains an acrylic resin and is porous, the pressure-sensitive adhesive layer 20 exhibits a white color due to irregular reflection due to being porous, and has a brightness V of 7 or more. Even in this case, by coloring the release sheet 30, the difference between the color of the surface of the release sheet 30 on the release layer 32 side and the color of the pressure-sensitive adhesive layer 20 can be increased to obtain the same effect as described above. can be done.

(Example 1)
Examples and comparative examples according to the present disclosure will be described below.
As Example 1, first, Powertight (registered trademark) WQ-1000 manufactured by Nippon Paint Industrial Coatings Co., Ltd. was stirred while containing air bubbles, and 20 sb of an adhesive air bubble-containing composition having a specific gravity of 0.4 g / m ² was added. made. 20 sb of the pressure-sensitive adhesive bubble-containing composition was applied to a 900-mm-wide Smilies (registered trademark) SLK-73Z (release sheet 30) manufactured by Sumika Kakoshi Co., Ltd. with a comma coater at a line speed of 25 m/min at a line speed of 30 g/m ^{2 .} (Weight after drying) After coating, drying in a drying oven at about 100°C, and laminating so as to face the back side of the sheet member 10, the sheet 1 with adhesive according to Example 1 was obtained. . The color observed from the release layer 32 side of Smilies (registered trademark) SLK-73Z is brown, and the pressure-sensitive adhesive bubble-containing composition 20sb is white. The color of the release layer 32 side of the Smilies (registered trademark) SLK-73Z and the color of the adhesive bubble-containing composition 20sb after drying were measured using a spectrophotometer (trade name: CM-3700A) manufactured by Konica Minolta Holdings, Inc. and calculated the color difference, the color difference ΔE ^* was 9.5.

(Example 2)
In Example 2, as the release sheet 30, Smilies (registered trademark) SLK-73Z in Example 1 was replaced with SSP-70SBX-K manufactured by Shinomura Chemical Industry Co., Ltd., and the others were the same as in Example 1. An adhesive-attached sheet 1 according to Example 2 was obtained. The color observed from the release layer 32 side of the SSP-70SBX-K is yellow. Similarly, the color of the release layer 32 side of SSP-70SBX-K and the color of the pressure-sensitive adhesive bubble-containing composition 20sb after drying were measured, and the color ^difference was calculated. Met.

(Example 3)
As Example 3, carbon black was added to Powertight (registered trademark) WQ-1000 in Examples 1 and 2 to make a black pressure-sensitive adhesive bubble-containing composition 20sb. As a result, the adhesive-attached sheet 1 according to Example 3 was obtained. When the color of the release layer 32 side of Shinomura Chemical Industry SSP-70SBX-K and the color of the adhesive bubble-containing composition 20sb after drying were measured with the above CM-3700A, the former in the Munsell color system was 5Y 9/10 and the latter was 10B 1/2. As a result of calculating the difference between the two colors from the above Munsell value, the difference ΔV in brightness was 8, the difference ΔH in hue was 8, and the difference ΔC in chroma was 5. Also, the color difference ΔE ^* was 52.4.

(Comparative example 1)
In Comparative Example 1, as the release sheet 30, instead of Smilies (registered trademark) SLK-73Z in Example 1, RHB80DM manufactured by San A Kaken was used, and the others were the same as in Example 1. The adhesive according to Comparative Example 1 An agent-coated sheet 1 was obtained. The color observed from the release layer 32 side of RHB80DM is white. Similarly, the color of RHB80DM on the release layer 32 side and the color of the adhesive bubble-containing composition 20sb after drying were measured, and the color difference ΔE ^* was calculated to be 1.4.

(Comparative example 2)
In Comparative Example 2, as the release sheet 30, Smilies (registered trademark) SLK-73Z in Example 1 was replaced with Cereal (registered trademark) BX8A manufactured by Toray Advanced Film Co., Ltd., and the rest was the same as in Example 1. As a result, a pressure-sensitive adhesive sheet 1 according to Comparative Example 2 was obtained. Therapeal (registered trademark) BX8A is made of transparent PET, and the color observed from the release layer 32 side is transparent. Similarly, the color of the releasing layer 32 side of Therapeal (registered trademark) BX8A and the color of the adhesive bubble-containing composition 20sb after drying were measured, and the color ^difference was calculated. was 3.

(Comparative Example 3)
In Comparative Example 3, carbon black was kneaded into a release sheet 30 whose release base sheet was made of paper and the Munsell value of the surface side to which the adhesive bubble-containing composition 20sb was applied was set to 10B 1/2. was the same as in Example 3, that is, 20 sb of the black adhesive bubble-containing composition was applied to obtain an adhesive-attached sheet 1 according to Comparative Example 3. As a result of measuring and calculating the color difference between the release sheet 30 and the pressure-sensitive adhesive bubble-containing composition 20sb, the brightness difference ΔV was 1, the hue difference ΔH was 1, and the chroma difference ΔC was 1. Also, the color difference ΔE ^* was 1.2.

(Evaluation: Visual confirmation of adhesive coming off)
During the production of each adhesive-attached sheet 1 according to Examples and Comparative Examples, after coating and drying the adhesive bubble-containing composition 20sb, before lamination with the sheet member 10, coating on the release sheet 30, The appearance of the dried pressure-sensitive adhesive bubble-containing composition 20sb was visually confirmed from a distance of 1 m. In addition, in order to cause coating omissions of the composition 20sb containing pressure-sensitive adhesive bubbles, the amount of the composition 20sb containing pressure-sensitive adhesive bubbles to be applied was intentionally reduced during the production. As a result, ◯ indicates that the adhesive bubble-containing composition 20sb (adhesive layer 20) of 1 mm or more was clearly visible, and x indicates that even if 1 mm or more of the adhesive bubble-containing composition was missed, it was overlooked.

Table 1 shows the evaluation results of the above Examples and Comparative Examples.

(Evaluation results)
The evaluation results were as shown in Table 1. Also, as an example of the coating-missing appearance, FIG. It can be confirmed from the photograph that the coating missing portion is easily visible. From the results in Table 1, when the color difference ΔE ^* between the release sheet 30 and the adhesive 20s (adhesive layer 20) is 4 or more, it is ◯, and when it is less than 4, it is x, confirming the effectiveness of the present disclosure.

The adhesive-attached sheet and the method for producing the same according to the present invention have been described above while showing the embodiments. However, the invention is not limited to the above embodiments or the description thereof. The above embodiment is an example, and the technical idea described in the claims of the present invention, which has substantially the same configuration and has the same effect, is the present invention in any case. It is included in the technical scope of the invention.

REFERENCE SIGNS LIST 1 adhesive-attached sheet 10 sheet member 11 base sheet 12 pattern layer 20 adhesive layer 20s adhesive 20sb adhesive bubble-containing composition 20a concave shape 30 release sheet 31 release base sheet 32 release layer

Claims (9)

A method for producing an adhesive sheet including a sheet member, an adhesive layer, and a release sheet,
The release sheet includes a release base sheet,
A pressure-sensitive adhesive layer forming step of applying a pressure-sensitive adhesive to one side surface of the release sheet and then drying or curing the pressure-sensitive adhesive layer to form the pressure-sensitive adhesive layer on the release sheet;
a sheet member laminating step of laminating the adhesive layer and the sheet member so as to face each other;
The pressure-sensitive adhesive layer forming step includes a pressure-sensitive adhesive appearance checking step of checking the coating appearance of the pressure-sensitive adhesive applied to the release sheet. The release sheet further comprises a release layer,
The release layer is provided on the one side surface of the release sheet,
The method for producing an adhesive-attached sheet according to claim 1, wherein in the adhesive layer forming step, the adhesive layer is applied to the release layer. 3. The method for producing a pressure-sensitive adhesive sheet according to claim 1, wherein a color difference ΔE ^* between said one side of said release sheet and said pressure-sensitive adhesive layer is 4 or more.
Here, in the L ^* a ^* b ^* color system defined in JIS Z8729, the color of the pressure-sensitive adhesive layer is L ^* _1a ^* _1b ^* ₁ , and the color of the one side surface of the release sheet is L. ^* ₂ a ^* ₂ b ^* ₂ ,
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2
ΔL ^* =L ^* ₂ -L ^* ₁
Δa ^* = a ^* ₂ - a ^* ₁
Δb ^* =b ^* ₂ -b ^* ₁ 4. The method according to any one of claims 1 to 3, wherein a difference ΔV between the brightness of the one side surface of the release sheet and the brightness of the pressure-sensitive adhesive layer is 4 or more, regarding the brightness V specified in JIS Z8721. A method for producing the pressure-sensitive adhesive sheet described. 5. The method according to any one of claims 1 to 4, wherein a difference ΔH between the hue of the one side surface of the release sheet and the hue of the pressure-sensitive adhesive layer is 4 or more, regarding the hue H defined in JIS Z8721. A method for producing the pressure-sensitive adhesive sheet described. 6. The difference ΔC between the chroma of the one side surface of the release sheet and the chroma of the pressure-sensitive adhesive layer is 4 or more with respect to the chroma C specified in JIS Z8721. 2. A method for producing the pressure-sensitive adhesive sheet according to item 1. 7. The method for producing an adhesive sheet according to any one of claims 1 to 6, wherein the adhesive layer has a brightness V of 7 or more according to JIS Z8721. 8. The method for producing a pressure-sensitive adhesive sheet according to any one of claims 1 to 7, wherein the pressure-sensitive adhesive layer contains an acrylic resin and is porous. An adhesive sheet comprising a sheet member, an adhesive layer and a release sheet,
The release sheet includes a release base sheet,
A pressure-sensitive adhesive sheet having a color difference ΔE ^* between one surface of the release sheet and the pressure-sensitive adhesive layer of 4 or more.
Here, in the L ^* a ^* b ^* color system defined in JIS Z8729, the color of the pressure-sensitive adhesive layer is L ^* _1a ^* _1b ^* ₁ , and the color of the one side surface of the release sheet is L. ^* ₂ a ^* ₂ b ^* ₂ ,
ΔE ^* = ((ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² ) ^1/2
ΔL ^* =L ^* ₂ -L ^* ₁
Δa ^* = a ^* ₂ - a ^* ₁
Δb ^* =b ^* ₂ -b ^* ₁

Images