JP5232575B2 - Release paper, method for producing the same, adhesive sheet using the release paper, and adhesive sheet roll - Google Patents

Description

 The present invention relates to a release paper and a method for producing the same, and an adhesive sheet and an adhesive sheet roll using the release paper.

Adhesive sheets can be easily adhered to adherends at room temperature with a pressure of about acupressure and are widely used for commercial, office, process management, logistics management, home use, labels, seals, stickers, Used in the form of emblems, delivery slips, etc.
An adhesive sheet is generally composed of a sheet-like adhesive sheet substrate, an adhesive layer laminated on the adhesive sheet substrate, and a release paper laminated on the adhesive layer. Various adhesive sheets with different levels of adhesive strength have been developed, from weakly adhesive types such as re-peelable adhesive sheets that can be peeled off and re-adhered once adhered to the body, to strong adhesive types. Yes. In addition to such a single-sided adhesive sheet, a double-sided adhesive sheet in which an adhesive layer is provided on one side of a release paper has been developed. The pressure-sensitive adhesive sheet for double-sided adhesion is usually stored and used in a wound state.

The pressure-sensitive adhesive sheet has a problem that air (air) is entrapped when it is attached to the adherend, and air is easily trapped between the adherend and the pressure-sensitive adhesive layer, so-called “swelling” can easily occur and the appearance is impaired. This problem is particularly noticeable in the strong adhesive type pressure-sensitive adhesive sheet that is difficult to re-stretch.
As one of the causes of the “swelling”, it is considered that the surface of the pressure-sensitive adhesive layer is usually flat. Therefore, in order to improve this “swelling”, it has been proposed to provide an uneven structure on the surface of the pressure-sensitive adhesive layer. This is because by providing an uneven structure on the surface of the pressure-sensitive adhesive layer, when the pressure-sensitive adhesive sheet is affixed to an adherend, a communication gap leading to the outside is formed between the pressure-sensitive adhesive sheet and the adherend. The air-releasing property is imparted, and the entrained air is allowed to escape to the outside through the communication gap.
In addition, by providing an uneven structure on the surface of the pressure-sensitive adhesive layer, the peeling force on the adherend can be adjusted to be weak.

In the case of single-sided adhesive, a pressure-sensitive adhesive sheet having a concavo-convex structure generally uses a release paper having a concavo-convex structure on the surface, and a pressure-sensitive adhesive is applied on the surface provided with the concavo-convex structure of the release paper. After providing the pressure-sensitive adhesive layer, it is produced by bonding the pressure-sensitive adhesive layer and the pressure-sensitive adhesive sheet substrate. Separately, an adhesive is applied on one side of the adhesive sheet base material to produce an adhesive sheet body with an adhesive layer, and peeled off so that the uneven structure of the release paper is transferred to the adhesive layer. It can also be manufactured by laminating paper and an adhesive sheet body. On the other hand, in the case of a pressure-sensitive adhesive sheet for double-sided adhesion, a pressure-sensitive adhesive is applied to the release paper so that the concavo-convex structure of the release paper is transferred, and then wound to form a wound body.
The release paper is a laminate in which a sealing layer made of a thermoplastic resin or the like and a release layer made of a release agent such as silicone are sequentially laminated on a release substrate such as paper. And the release paper which has an uneven structure on the surface is formed by embossing this laminated body. (For example, refer to Patent Documents 1 and 2).
And as above-mentioned, the uneven structure of the release paper was transcribe | transferred on the adhesive layer surface by apply | coating an adhesive on the release layer of a release paper, or bonding a release paper and an adhesive sheet main body. A pressure-sensitive adhesive sheet having an uneven structure is obtained.

By the way, as a method of embossing the release paper, for example, a method of forming an uneven structure on the surface of the release paper by sandwiching the release paper between male and female embossing rolls and applying pressure from both sides of the release paper can be mentioned.
However, the release paper embossed with male and female embossing rolls has not only the surface of the release paper on the side where the resin layer and release layer are laminated, but also the other surface (back surface) of the release paper. It is formed. Therefore, in the case of a pressure-sensitive adhesive sheet for single-sided adhesion, if the pressure-sensitive adhesive sheet is wound up or stacked after storage for the purpose of storage, the pressure-sensitive adhesive sheet substrate surface of the pressure-sensitive adhesive sheet in contact with the back surface of the release paper is The uneven structure was sometimes transferred.
When the concavo-convex structure is formed on the surface of the pressure-sensitive adhesive sheet substrate, it becomes difficult to print clearly when printing or the like is performed on the surface of the pressure-sensitive adhesive sheet substrate. In addition, when the pressure-sensitive adhesive sheet is cut and die-cut, the manner of entering the die-cutting blade changes, so that a so-called die-cutting defect in which a cut portion and a non-cut portion are generated easily occurs.

Therefore, in order to prevent the uneven structure of the back side of the release paper from being transferred to the surface of the adhesive sheet substrate, a thermoplastic resin or the like is applied to the back side of the release paper, or a film is laminated, The back surface had to be flat. However, the method of applying a resin or laminating a film increases the number of manufacturing steps, which easily increases the manufacturing cost and is troublesome.
Therefore, as a method for flattening the back surface of the release paper without increasing the number of manufacturing steps, a male emboss roll and an elastic roll with a flat surface are used, and the release on the side where the resin layer and the release layer are laminated A method of embossing by passing between two rolls so that the embossing roll is in contact with the front side of the paper and the elastic roll is in contact with the back side of the release paper (see, for example, Patent Document 3), or the release paper is heated. There has been proposed a method (for example, see Patent Document 4) in which a release paper having an uneven structure is manufactured by embossing between a rubber roll and an embossing roll.
Japanese Utility Model Publication No.6-20043 JP 2003-336017 A Japanese Patent Laid-Open No. 9-141812 Special Table 2002-544364

  However, the pressure-sensitive adhesive sheet using a method of embossing the release paper with a male-female embossing roll or a release paper having a concavo-convex structure formed by the methods described in Patent Documents 3 and 4 is a transparent adhesive layer. It was difficult to get enough sex. Therefore, when a single-sided adhesive sheet with a transparent adhesive sheet substrate is attached to an adherend, or when an adhesive sheet for double-sided adhesive is attached to a transparent adherend, Colors and patterns may become unclear.

By the way, when producing a double-sided adhesive sheet, it is necessary to provide a relief structure on the back side of the release paper. Such release paper is required to have different peel forces for the pressure-sensitive adhesive layer on the front surface and the back surface. Adjustment of the peeling force is achieved by changing the type of release agent, the thickness of the release layer, the shape of the concavo-convex structure, and the like between the front and back surfaces.
However, in the method of embossing release paper with male and female type embossing rolls, although the uneven structure can be formed on both sides of the release paper at once, the uneven structure formed on the front and back surfaces has a relationship between the key and the keyhole. Therefore, an uneven structure having the same shape is formed. Therefore, it is difficult to adjust the difference in peeling force by changing the shape of the concavo-convex structure.

  In addition, as described in Patent Documents 3 and 4, when an uneven structure is formed using an elastic roll having a flat surface and a male embossing roll, the uneven structure is once formed on the surface of the release paper. Later, it is difficult to form a new concavo-convex structure in the same manner on the back surface of the release substrate. This is because it is necessary to press the embossing roll with a high pressure (for example, 1900 N / cm) in order to form a concavo-convex structure in the resin layer in which the thermoplastic resin is solidified or in the release layer. Therefore, when forming a concavo-convex structure on the back surface of the release paper, the elastic roll is pressed against the surface on which the concavo-convex structure was previously formed with a high pressure. As a result, the concavo-convex structure previously formed on the surface of the release paper was crushed by the elastic roll, and it was difficult to maintain the shape.

  This invention is made | formed in view of the said situation, Comprising: The release sheet which can obtain the adhesive sheet provided with the adhesive layer excellent in transparency, and an adhesive sheet winding body, and its manufacturing method are provided. For the purpose. Moreover, it aims at providing the manufacturing method of the release paper which can manufacture easily the release paper suitable for the adhesive sheet for double-sided adhesion. Furthermore, it aims at providing the adhesive sheet provided with the adhesive layer excellent in transparency, and an adhesive sheet winding body.

As a result of intensive studies by the present inventors, the cause that the transparency of the pressure-sensitive adhesive layer is not sufficiently obtained is as shown in FIG. 10, the convex portion constituting the concave-convex structure X formed on the surface of the release paper 60. found that in the ridges R _X of the periphery of the T _X. In other words, it has been found that the convex portion T _X having the concave portion H _X affects the transparency of the pressure-sensitive adhesive layer. That is, when a pressure-sensitive adhesive sheet is prepared using a release paper in which the convex portions T _X have the concave portions H _X , the pressure-sensitive adhesive does not easily penetrate into the concave portions S _X when the adhesive is applied on the release layer. As a result, air accumulation is generated, and as a result, the uniform uneven structure is hardly transferred to the pressure-sensitive adhesive layer, and the transparency of the pressure-sensitive adhesive layer is likely to be lowered. Therefore, the release paper of the present invention has been completed based on the idea that the convex portion T _X may have a structure without the concave portion H _X.

As a result of the peripheral edge of the convex portion T _X has examined the cause of the ridge, and a method for embossing a release paper in male female embossing roll, the method as described in Patent Documents 3 and 4, the thermoplastic resin solidified resin layer and that, since the pressing an embossing roll on the release layer, there is no escape of the volume when irregularities are formed, so that the peripheral edge of the convex portion T _X and found that ridges. Accordingly, the present inventors have peripheral edge of the convex portion T _X has examined the means for preventing from being raised. As a result, the present invention has been completed based on the idea that the concavo-convex structure should be formed before the solidification of the thermoplastic resin is completed.

The present invention employs the following configuration.
[1] A release paper for use in contact with the adhesive layer, on one surface of a release paper base material, the thermoplastic resin layer A _X and the peeling layer B _X are sequentially laminated, the thermoplastic resin layer On the surface of the release paper on the side where A _X and release layer B _X are laminated, the uneven structure X having a mode pitch of 100 to 2000 μm and a mode depth of 10 to 140 μm is provided. Each of the convex portions T _X constituting the release paper does not have a hollow portion H _X.
However, the convex portion T _X, the reference in the cross-section image when measuring uneven structure X a laser microscope, a point away 10μm upwardly from the bottom when the depth direction of the uneven structure X and the vertical direction and a point, from the point crossing the reference line drawn in a direction perpendicular to the through vertically the reference point plus slope is that of the upper portion to the point crossing in negative slope, the recess H _X , there is the conversion point, the slope of changes from negative to positive, the height difference .DELTA.G _X between the top of the convex portion T _X is before and after the shift conversion point is 5μm or more with the shift conversion point, the slope is negative portion To the positive part.
[2] The release paper according to [1], wherein the surface opposite to the side on which the thermoplastic resin layer _AX is laminated is flat.

[3] The side on which the thermoplastic resin layer _AY and the release layer _BY are sequentially laminated on the other surface of the release paper base material, and the thermoplastic resin layer _AY and the release layer _BY are laminated. of the surface of the release paper, the most frequent pitch 100 to 2000, with an uneven structure Y modal depth of 10～140Myuemu, each protrusion _{T Y} depression portion _{H Y} constituting the uneven structure Y The release paper according to [1], which does not have.
However, the convex portion _TY is based on a point 10 μm away from the lowermost portion in the cross-sectional image when the concave-convex structure Y is measured with a laser microscope when the depth direction of the concave-convex structure Y is set as the vertical direction and a point, from the point crossing the reference line drawn vertically to the reference point with respect to street vertical direction plus slope is that of the upper portion to the point crossing in negative slope, the recess H _Y , there is the conversion point, the slope of changes from negative to positive, the height difference .DELTA.G _Y between the top of the convex portion T _Y are before and after the shift conversion point is 5μm or more with the shift conversion point, the slope is negative portion To the positive part.

[4] The release paper according to [1] or [2] and the pressure-sensitive adhesive sheet body having a pressure-sensitive adhesive layer on one side of the pressure-sensitive adhesive sheet base material are provided with a release layer of the release paper and a pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet body. A pressure-sensitive adhesive sheet characterized by being laminated on the inside.
[5] A first release paper and a second release paper in which a thermoplastic resin layer and a release layer are sequentially laminated on one surface of a release paper base, the release layer is placed inside through an adhesive layer. The first release paper and the second release paper are the release papers described in [1] or [2], and the first release paper and the second release paper with respect to the pressure-sensitive adhesive layer. A pressure-sensitive adhesive sheet having different peeling forces.

[6] A pressure-sensitive adhesive sheet roll comprising the pressure-sensitive adhesive sheet comprising the release paper according to [3] and a pressure-sensitive adhesive layer, and the pressure-sensitive adhesive sheet being wound.
However, the release layer on the release layer B _X side surface of the release paper is different from the release force on the adhesive layer on the release layer _BY side surface, and the release layer having a large release force. It is assumed that the pressure-sensitive adhesive layer is provided on the top and is wound with the release layer having a small peeling force as the outside.

[7] A method for producing a release paper used in contact with an adhesive layer, wherein a first thermoplastic resin is applied on one surface of a release paper substrate, and a pressing roll having a flat surface immediately By passing the surface on which the first thermoplastic resin is applied between the cooling roll having the concavo-convex structure X ′ on the surface so that the surface is in contact with the cooling roll, the concavo-convex structure is formed on the release paper substrate. a first step of the thermoplastic resin layer a _X forms a laminate M _X laminated with X, the thermoplastic resin layer a _X of the laminate M _X, on the surface irregular structure X is formed, to hold the uneven structure X, the production method of the release paper, characterized in that it comprises a second step of applying a first release agent forming the release layer B _X.
However, the uneven structure X ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure X is a structure in which the uneven structure X ′ is inverted.

[8] The shape of the recess S _X in a horizontal section cut at a height of 10 μm from the lowest part of the concavo-convex structure X is a 2n square (n is a positive integer), and a diagonal line K connecting the opposing vertices of the 2n square one _X is said to be parallel to the conveying direction of the laminate M _X in the second step, and forming an uneven structure X on the surface of the thermoplastic resin layer a _X [7 ] The manufacturing method of the release paper of description.
[9] The release paper manufacturing method according to [7] or [8], wherein the pressure of the pressing roll in the first step is 30 to 100 N / cm.

[10] After the second step, a second thermoplastic resin is further applied on the other surface of the release paper base, and immediately, a pressing roll with a flat surface and a concavo-convex structure Y ′ on the surface. The surface having the concavo-convex structure Y on the other surface of the release paper base material is passed between the cooling roll having the second thermoplastic resin so that the surface coated with the second thermoplastic resin is in contact with the cooling roll. a third step of forming a laminate M _Y of the thermoplastic resin layer a _Y are laminated, the thermoplastic resin layer a _Y of the laminate M _Y, on the surface irregular structure Y is formed, uneven structure Y to hold, by applying a second release agent, wherein the peeling layer B _X, characterized in that it comprises a fourth step of forming a different separation layer B _Y peeling strength [8] or [9] The method for producing a release paper according to [9] .
However, the uneven structure Y ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure Y is a structure in which the uneven structure Y ′ is inverted.

[11] The unevenness (n is a positive integer) recess S _Y is 2n rectangular shape in horizontal cross section cut at a height of 10μm from the bottom of the structure Y is, diagonal line connecting the vertexes of opposing the 2n square K _The uneven structure Y is formed on the surface of the thermoplastic resin layer _AY so that one of _Y is parallel to the transport direction of the laminate MY in the fourth step [10. ] The manufacturing method of the release paper of description.
[12] The method for producing a release paper as described in [10] or [11], wherein the pressure of the pressing roll in the third step is 30 to 100 N / cm.
In the above inventions, the release agent constituting the release layer B _X, release agent constituting the release layer B _Y, the first release agent, the second release agent, each silicone resin, wax, alkyd resin, an alkyd A release agent selected from a modified silicone, an acrylic-modified silicone, a fluororesin, and a long-chain alkyl pendant release agent is preferable.

According to the release paper of this invention, the adhesive sheet provided with the adhesive layer excellent in transparency, and an adhesive sheet winding body can be obtained.
Moreover, according to the manufacturing method of the release paper of this invention, the release paper of the said invention can be manufactured. Moreover, the release paper suitable for the adhesive sheet for double-sided adhesion can be easily produced. Therefore, according to the present invention, it is possible to easily produce a release paper suitable for both a single-sided adhesive sheet and a double-sided adhesive sheet.
Furthermore, the pressure-sensitive adhesive sheet and pressure-sensitive adhesive sheet roll of the present invention are provided with a pressure-sensitive adhesive layer excellent in transparency.

[Release paper]
<First Embodiment>
One embodiment of the release paper of the present invention will be described. For convenience of explanation, the thickness ratios of the release paper substrate, the thermoplastic resin layer, the release layer, the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive sheet substrate in the drawings used in the following description are different from actual ones. Moreover, in FIGS. 2-11, the same code | symbol may be attached | subjected to the component same as FIG. 1, and the description may be abbreviate | omitted.
FIG. 1 is a schematic cross-sectional view for illustrating an example of a cross-sectional structure of the release paper of the present invention. The release paper 10 has a release paper base material 11, on one surface of the release paper substrate 11, a thermoplastic resin layer A _X and the peeling layer B _X are sequentially stacked. 2 is a cross-sectional image showing an example when measured by actually laser microscope of the surface of the peeling layer B _X in FIG.

Release paper 10 of the present embodiment, the surface on the side of the release paper 10 to the thermoplastic resin layer _{A X} and the release layer _{B X} are stacked, the most frequent pitch 100 to 2000, the modal depth 10~140μm The concavo-convex structure X is provided. Uneven structure X includes a plurality of protrusions T _X, is composed of a plurality of recesses S _X adjacent thereto.
In the present invention, the “convex portion T _X ” is defined as shown below in a cross-sectional image when the concavo-convex structure X is measured with a laser microscope.
That is, as shown in FIG. 2, a point 10 μm away from the lowest α _X when the depth direction of the concavo-convex structure X (the direction perpendicular to the entire surface of the release paper 10) is set as the vertical direction is a reference point β _X, and an upper portion from a point L _X1 that crosses the reference line L _X drawn through the reference point β _X in a direction perpendicular to the vertical direction with a positive inclination to a point L _X2 that crosses with a negative inclination ( The hatched portion in FIG. 2 is defined as “convex portion T _X ”. Note that the cross-sectional image as shown in FIG. 2 is obtained in the same manner as the method for obtaining the mode depth described later.
In the present invention, the “recessed portion S _X ” refers to a region other than the protruding portion T _X. It is preferable that the concavo-convex structure X is a structure in which a plurality of concave portions S _X are separately dispersed and arranged. In that case, a region surrounded by the plurality of protrusions T _X.

The most frequent pitch of the concavo-convex structure X corresponds to the most frequent value of the pitch P _X (distance between adjacent convex portions T _X ) in FIG. Also, modal depth of the concavo-convex structure X is the entire surface perpendicular to the direction of the depth D _{X (release} paper 10 in FIG. 2, and _X 'top γ of _X' any protrusions T, convex portions T corresponds to the most frequent value of the distance at the bottom alpha _'X) of _X' concave S adjacent to _X '.

Specifically, the most frequent pitch of the concavo-convex structure X is a value measured by the following method.
First, on the surface where the concavo-convex structure X exists, a square region having a side of about 5 mm is randomly extracted to obtain an image measured with a laser microscope. The conditions for measurement with a laser microscope are preferably a lens magnification of 200 to 2000 times and a measurement pitch of 150 to 2000 μm. The image is acquired from the direction in which the release paper surface is viewed vertically.
Then, this image is waveform-separated by Fourier transform to obtain an FFT image (fast Fourier transform image). Next, the distance from the 0th order peak to the 1st order peak in the profile of the FFT image is obtained. The reciprocal of the distance thus obtained is the most frequent pitch in this region. Such processing is similarly performed for a total of 25 regions of the same area selected at random, and the most frequent pitch in each region is obtained. The average value of the mode pitches in the 25 regions thus obtained is the mode pitch of the concavo-convex structure X. At this time, the regions are preferably selected at least 1 mm apart, and more preferably 5 mm to 1 cm apart.

  The most frequent pitch of the concavo-convex structure X is 100 to 2000 μm, preferably 150 to 1000 μm, and more preferably 200 to 600 μm. When the most frequent pitch is 100 μm or more, when an adhesive sheet is produced using the obtained release paper, it is possible to ensure air bleeding and increase the contact area of the adhesive so that sufficient adhesive force can be obtained. become. Further, when the most frequent pitch is 2000 μm or less, the concavo-convex structure X becomes invisible with the naked eye, and the contact area of the pressure-sensitive adhesive can be prevented from being increased more than necessary, so that air bleedability can be maintained.

The mode depth of the concavo-convex structure X is specifically a value measured by the following method.
First, a cross section of the concavo-convex structure X is obtained by cutting along a plane perpendicular to the surface of the release paper. In this cross section, and extracted five square area that can be observed protrusions T _X (square area becomes 5-10 times the most frequent pitch of one side uneven structure X) at random, measured with a laser microscope The obtained cross-sectional image is obtained. The conditions for measurement with a laser microscope are the same as in the case of the most frequent pitch.
From this cross-section image, it reads five data D _X in the manner of FIG. That is, the _X 'top γ of _X' any protrusions T, the distance of the bottom alpha _'X of _X' concave S adjacent to _X 'which convex portion T and D _X. Similarly, obtained from a total of five laser microscope images, respectively five, the data of a total of 25 D _X. At this time, the regions are preferably selected at least 1 mm apart, and more preferably 5 mm to 1 cm apart.
Then, an equatorial direction profile of a two-dimensional Fourier transform image is created, and data on the most frequent depth of the concavo-convex structure X is obtained from the reciprocal of the primary peak.

  The most frequent depth of the concavo-convex structure X is 10 to 140 μm, preferably 11 to 50 μm, and more preferably 15 to 40 μm. When the mode depth is 10 μm or more, air release properties can be secured when an adhesive sheet is produced using the obtained release paper. Moreover, when the mode depth is 140 μm or less, a decrease in the adhesive strength of the pressure-sensitive adhesive can be suppressed, and the appearance after adhesion to the adherend can be favorably maintained.

The shape of the recess S _X in the horizontal cross section cut at a height of 10μm from the bottom alpha _X of the concavo-convex structure X is an equilateral triangle, square, regular polygonal or modifications, such as a regular hexagon (such as a rectangle or an isosceles triangle) May be selected, and may be circular or elliptical, but a 2n square (n is a positive integer) is particularly preferable.
Incidentally, the horizontal cross section cut at a height of 10μm from the bottom alpha _X of the concavo-convex structure X is a plane containing the reference line L _X shown in FIG.

The release paper 10 of the present invention is characterized in that each convex portion T _X constituting the concavo-convex structure X does not have a hollow portion H _X.
In the present invention, the “recessed portion H _X ” has a turning point at which the inclination turns from minus to plus, and the turning point ΔG _X with respect to the top of the convex portion T _X having the turning point is 5 μm or more. This is a region from the front and back to the portion where the inclination is negative to the portion where the inclination is positive. Hereinafter, it demonstrates concretely using drawing.

For example, when embossing is performed by a method described in Patent Document 3, a release paper 60 as shown in FIG. 10 is obtained. When the uneven structure X of the release paper 60 is measured with a laser microscope, a cross-sectional image as shown in FIG. 11 is obtained. In this cross section image, inclination and conversion point C _X points changes from negative to positive, the conversion point height difference .DELTA.G _X is 5μm or more and the top gamma _X of the convex portion T _X having a shift conversion point C _X C _X before and after the gradient is a region of the recess H _X from the partial is negative to the part is positive.
Here, FIG. 10 is a schematic sectional view for illustrating an example of sectional structure of the release paper obtained by the method described in Patent Document 3, FIG. 11, the actual surface of the release layer B _X in FIG. 10 It is a cross-sectional image which shows an example at the time of measuring with a laser microscope.

When the recess H _X is uneven by embossing, there is no escape space for the volume corresponding to the recess, so that the periphery of the protrusion T _X is raised as shown in FIG. obtained _{by X} is formed, inside it surrounded the ridges R _X corresponds to the recessed portion H _X.
When preparing a pressure-sensitive adhesive sheet with a release paper having a recess H _X, adhesive is hard to uniformly penetrate in the recess S _X when forming an adhesive layer on the release layer, as a result, the pressure-sensitive adhesive A uniform uneven structure is hardly transferred to the layer, and the transparency of the pressure-sensitive adhesive layer tends to decrease.

However, as shown in FIG. 1, if the release paper 10 of the present invention, since no respective protrusion portions T _X is recess H _X constituting the concavo-convex structure X, and applying an adhesive to the release layer uniformly easily penetrate into adhesive recess S _X when. Therefore, it is considered that a uniform uneven structure is transferred to the pressure-sensitive adhesive layer, and the transparency of the pressure-sensitive adhesive layer can be maintained well.
Incidentally, the presence or absence of the recessed portion H _X is an uneven structure was measured with a laser microscope in the same manner as in the measurement method of the modal depth described above can be confirmed from the obtained cross-sectional image.

The material which comprises the release paper 10 of this invention can be suitably selected according to the use of release paper.
As the release paper substrate 11, for example, a plastic film or paper can be used.
Examples of the material constituting the plastic film, preferably has a melting point temperature is higher than the thermoplastic resin constituting the thermoplastic resin layer A _X to be described later, for example, polypropylene, polyethylene, polyethylene terephthalate and polybutylene terephthalate polyester, poly Examples include vinyl chloride.
Examples of the paper include cast coated paper, art paper, coated paper, high quality paper, craft paper, and glassine paper.
Further, as the release paper base 11, vapor-deposited paper, synthetic paper, cloth nonwoven fabric, metal foil or the like can be used.

The release paper substrate 11 may have a single layer structure or a multilayer structure. Examples of the release paper substrate having a multilayer structure include a laminate obtained by laminating an anti-curl agent layer and a sealing undercoat layer on the above-described plastic film or paper. In addition, in the case of a multi-layer release paper substrate, the outermost layer on the side opposite to the side on which the thermoplastic resin layer _AX is laminated (the back side) is formed by applying a resin such as a thermoplastic resin. A layer is preferred. A resin constituting the resin layer may be the same as the resin constituting the thermoplastic resin layer A _X to be described later, may be different, preferably identical.
The thickness of the release paper substrate 11 is preferably 7 to 500 μm, more preferably 30 to 200 μm, and still more preferably 50 to 170 μm. When the thickness of the release paper substrate 11 is 7 μm or more, even when forming the minimum uneven structure X in which the mode pitch and mode depth are the minimum values within the above range, the lamination process can be performed stably. Etc., and the concavo-convex structure X can be easily formed. Moreover, if thickness is 500 micrometers or less, a release paper can be manufactured efficiently from a viewpoint of cost reduction by the processing speed at the time of manufacturing a release paper, the winding length of a release paper, the application quantity of resin, etc.

The thermoplastic resin constituting the thermoplastic resin layer A _X, for example, polypropylene, polyethylene, and polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyvinyl chloride and the like, but not particularly limited.
Preferably the thickness of the thermoplastic resin layer _{A X} is 10～160Myuemu, more preferably 15～80Myuemu, more preferably from 20 to 50 m. _If the thickness of the thermoplastic resin layer AX is 10 μm or more, the laminate can be stably laminated even when forming the minimum uneven structure X in which the mode pitch and mode depth are the minimum values within the above range. Processing etc. can be given and the uneven structure X can be formed easily. If the thickness is 160 μm or less, the release paper can be efficiently produced from the viewpoint of cost reduction due to the processing speed when producing the release paper, the winding length of the release paper, the amount of resin applied, and the like.

As the release agent constituting the release layer B _X, for example, silicone-based resins, various waxes, alkyd resins, alkyd-modified silicone, acryl-modified silicone, fluorine-based resin, such as long-chain alkyl pendant type release agents, especially It is not limited.
The thickness of the release layer _{B X} is a release agent is applied, it can be converted to the mass (dry weight) when dried, it is preferred that the dry mass is 0.1 to 5.0 g / ^{m 2,} 0. more preferably 3~3.0g / ^{m 2,} further preferably 0.5 to 2.0 g / ^{m 2.} When the dry mass is 0.1 g / m ² or more, a stable peeling force can be obtained even when forming the minimum uneven structure X in which the mode pitch and mode depth are the minimum values within the above range. It is done. Moreover, if dry mass is 5.0 g / m < ² > or less, a release paper can be manufactured efficiently from a viewpoint of cost reduction by the application speed of a release agent, the application amount of a release agent, and the like.

The release paper 10 shown in FIG. 1 preferably has a flat surface opposite to the side on which the thermoplastic resin layer _AX is laminated (the back surface of the release paper 10). If the back surface of the release paper 10 is flat, the pressure-sensitive adhesive sheet surface in contact with the back surface of the release paper can be maintained in a flat state even if the pressure-sensitive adhesive sheet is produced and wound or stacked for the purpose of storage or the like. In particular, if the release paper substrate 11 whose outermost layer on the back side of the release paper substrate 11 is a resin layer is used, the back surface of the release paper 10 can be more easily flattened.
In the present invention, “flat” means that the surface roughness Ra measured by an ultra-deep color 3D shape measuring microscope (VK-9500) is 2.5 μm or less. In the present invention, when the back surface of the release paper 10 is flat, it is preferable that the smoothness measured by “Oken type smoothness meter (model KB2S)” manufactured by Asahi Seiko is 300 seconds or more, More preferably, it is 1000 seconds or more.

(Manufacturing method of release paper)
The release paper 10 shown in FIG. 1 can be manufactured as follows. Here, an example of the manufacturing method of the release paper of this invention is demonstrated concretely using FIG.
First, the first thermoplastic resin 12 is applied on one surface of the release paper substrate 11, and immediately between the pressing roll 13 having a flat surface and the cooling roll 14 having a concavo-convex structure X ′ on the surface. The thermoplastic resin layer AX having the concavo-convex structure _X is laminated on the release paper base material 11 by passing the first thermoplastic resin 12 applied surface so that the surface is in contact with the cooling roll 14. to form a laminate M _X that (more than the first step.). Laminate M _X is the peeling roll 15 arranged on the opposite side of the pressing rolls 13 of the cooling roll 14 is pulled away from the cooling roll 14.
The uneven structure X ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure X is a structure in which the uneven structure X ′ is inverted. The mode pitch and mode height of the concavo-convex structure X ′ are values measured in the same manner as the mode pitch and mode height of the concavo-convex structure X.

Then, the thermoplastic resin layer A _X of the laminate M _X obtained in the first step, on the surface irregular structure X is formed so as to hold the uneven structure X, the first release agent coated to form a release layer B _X (more than the second step.) to obtain a release paper.

As a method for applying the first thermoplastic resin 12, a method in which the first thermoplastic resin 12 is heated and melted and extruded and laminated on the release paper substrate 11, or a thermoplastic that is soluble in water or an organic solvent is used. In the case of using a resin, a known method such as spray coating, bar coater, gravure coater or the like can be employed by dissolving in the resin, but as shown in FIG. 3, the first thermoplastic resin 12 melted in an extruder 16 is used. A method of extruding and laminating is preferable.
Examples of the method for applying the first release agent include spray coating, bar coater, gravure coater, kiss coater, air knife, blade coater, comma coater, die coater, and roll coater. Absent.

In the first step, conditions such as the pressure of the pressing roll 13, the resin temperature, and the processing speed are appropriately set according to the thickness of the release paper base and the purpose of use of the obtained release paper.
The pressure condition is preferably 30 to 100 N / cm.
The temperature condition is preferably 280 to 350 ° C.
The speed condition is preferably 2 to 500 m / min.

In the second step, as long as the first release agent can be applied so as to retain the concavo-convex structure X, the application conditions are not particularly limited, but the application amount of the first release agent is 0.1 to 2.0 g / m. ² is preferable, and the coating speed is preferably ² to 500 m / min, more preferably 10 to 300 m / min, and still more preferably 10 to 150 m / min.
Further, in order to apply the first release agent so as to hold the concavo-convex structure X, for example, the shape of the concave portion S _X in a horizontal section cut at a height of 10 μm from the lowest part α _X of the concavo-convex structure X shown in FIG. Is a 2n square (n is a positive integer), as shown in FIG. 4, one of the diagonal lines K _X connecting the opposite vertices of the 2n square (quadrangle) is formed in the laminate M _X in the second step. so as to be parallel to the conveying direction, in a first step, it is preferable to form an uneven structure X on the surface of the thermoplastic resin layer a _X.
Thus, the uniform release agent in the recess S _X is likely to penetrate, while retaining uneven structure X of the thermoplastic resin layer A _X, it can form a peeling layer B _X on the thermoplastic resin layer A _X.

In addition, when using the release paper base material of the multilayer structure whose outermost layer is a resin layer, the release paper base material of such a multilayer structure may be prepared and used for the production of the release paper, or the first step After that, a resin layer is formed by applying a resin to the back side of the plastic film or paper that becomes the main body of the release paper base, and finally the release paper base consisting of the main body and the resin layer of the plastic film or paper It is good.
When forming the resin layer, after applying the resin, immediately pass between the pressing roll with the flat surface and the cooling roll with the flat surface so that the surface with the resin applied contacts the cooling roll. Just do it.

  According to the release paper manufacturing method of the present invention, since the concavo-convex structure can be formed before the solidification of the thermoplastic resin is completed, it is easy to ensure the escape space of the volume corresponding to the concave portion. Therefore, it is difficult for the peripheral edge of the concave portion to be raised, and the concave-convex structure of the cross-sectional view as shown in FIG.

Moreover, since the release paper obtained in this way has a flat surface opposite to the side on which the thermoplastic resin layer _AX is laminated (the back side of the release paper), an adhesive sheet is prepared and stored. Even if it is wound up or stacked for the purpose, the adhesive sheet surface in contact with the back surface of the release paper can be maintained in a flat state. Therefore, the release paper of the present invention is particularly suitable for a single-sided adhesive sheet. Moreover, if two release papers of this invention are used, it is suitable also for the adhesive sheet for double-sided adhesion.

<Second Embodiment>
FIG. 5 is a schematic cross-sectional view for illustrating another example of the cross-sectional structure of the release paper of the present invention. In the release paper 20 of this example, a release paper base 21 and a thermoplastic resin layer _AX and a release layer B _X are sequentially laminated on one surface of the release paper base 21 to release the release paper base 21. A thermoplastic resin layer _AY and a release layer _BY are sequentially laminated on the other surface. FIG. 6 is a cross-sectional image showing an example when the surface of the release layer _BY of FIG. 5 is actually measured with a laser microscope.
The release paper 20 shown in FIG. 5 is different from the release paper 10 of the first embodiment described above in that the thermoplastic resin layer _AY and the release layer _BY are formed on the other surface of the release paper base 21. Since it is the point which is laminated | stacked sequentially, description about the same part as the release paper 10 of 1st Embodiment mentioned above is abbreviate | omitted, and only a different part is demonstrated.

The release paper 20 of the present embodiment has a mode pitch of 100 to 2000 μm on the surface of the release paper 20 on the side where the thermoplastic resin layer _AY and the release layer _BY are laminated (the back side of the release paper). An uneven structure Y having a depth of 10 to 140 μm is provided. Uneven structure Y has a plurality of protrusions T _Y, it is formed of a plurality of recesses S _Y adjacent thereto.
In the present invention, the “convex portion T _Y ” is defined as shown below in a cross-sectional image when the concavo-convex structure Y is measured with a laser microscope.
That is, as shown in FIG. 6, a reference point is a point 10 μm away from the lowest α _Y when the depth direction of the concavo-convex structure Y (the direction perpendicular to the entire surface of the release paper 20) is the vertical direction. beta and _Y, the upper portion of the reference line L _Y drawn vertically the reference point beta _Y relative as a vertical direction from the point L _Y1 crossing with positive slope, to the point L _Y2 crossing with negative slope ( The hatched portion in FIG. 6 is defined as “convex portion T _Y ”. Note that the cross-sectional image as shown in FIG. 6 is obtained in the same manner as the method for obtaining the mode depth described later.
Further, "concave S _Y" in the present invention is a region other than the convex portion T _Y. It is preferable that the concavo-convex structure Y is a structure in which a plurality of concave portions _SY are separately dispersed and arranged. In that case, a region surrounded by the plurality of protrusions T _Y.

Modal pitch of the concavo-convex structure Y corresponds to the mode of the pitch P _Y in FIG. 6 _(the distance of the convex portion T _Y adjacent to). Also, modal depth of the concavo-convex structure Y is the entire surface perpendicular to the direction of the depth D _{Y (release} paper 20 in FIG. 6, and _Y 'top γ of _Y' arbitrary convex portion T, the convex portion T corresponds to the most frequent value of the distance) of the bottom alpha _'Y of _Y' concave S adjacent to _Y '.

Specifically, the most frequent pitch of the concavo-convex structure Y is a value measured by the following method.
First, on the surface where the concavo-convex structure Y exists, a square region having a side of about 5 mm is randomly extracted to obtain an image measured by a laser microscope. The conditions for measurement with a laser microscope are preferably a lens magnification of 200 to 2000 times and a measurement pitch of 150 to 2000 μm. The image is acquired from the direction in which the release paper surface is viewed vertically.
Then, this image is waveform-separated by Fourier transform to obtain an FFT image (fast Fourier transform image). Next, the distance from the 0th order peak to the 1st order peak in the profile of the FFT image is obtained. The reciprocal of the distance thus obtained is the most frequent pitch in this region. Such processing is similarly performed for a total of 25 regions of the same area selected at random, and the most frequent pitch in each region is obtained. The average value of the mode pitches in the 25 regions thus obtained is the mode pitch of the concavo-convex structure X. At this time, the regions are preferably selected at least 1 mm apart, and more preferably 5 mm to 1 cm apart.

  The most frequent pitch of the concavo-convex structure Y is 100 to 2000 μm, preferably 150 to 1000 μm, and more preferably 200 to 600 μm. When the most frequent pitch is 100 μm or more, when producing a pressure-sensitive adhesive sheet roll using the obtained release paper, it is possible to ensure air bleeding and increase the contact area of the pressure-sensitive adhesive, thereby providing sufficient adhesive force. It will be obtained. Further, when the most frequent pitch is 2000 μm or less, the uneven structure Y cannot be visually recognized with the naked eye, and the contact area of the pressure-sensitive adhesive can be prevented from being increased more than necessary.

The mode depth of the concavo-convex structure Y is specifically a value measured by the following method.
First, a cross section of the concavo-convex structure Y is obtained by cutting along a plane perpendicular to the surface of the release paper. In this cross section, and extracted five square area that can be observed protrusions T _Y (square area to be 5 to 10 times the most frequent pitch of one side uneven structure Y) randomly, measured with a laser microscope The obtained cross-sectional image is obtained. The conditions for measurement with a laser microscope are the same as in the case of the most frequent pitch.
From this cross-section image, it reads five data D _Y as in FIG. That is, the _Y 'top γ of _Y' arbitrary convex portion T, a distance of the bottom alpha _'Y of _Y' concave S adjacent to _Y 'of the convex portion T and D _Y. Similarly, a total of 25 _DY data are obtained from each of five images from a total of five laser microscopes. At this time, the regions are preferably selected at least 1 mm apart, and more preferably 5 mm to 1 cm apart.
Then, an equatorial direction profile of a two-dimensional Fourier transform image is created, and data on the most frequent depth of the concavo-convex structure X is obtained from the reciprocal of the primary peak.

  The most frequent depth of the concavo-convex structure Y is preferably 10 to 140 μm, more preferably 11 to 50 μm, and still more preferably 15 to 40 μm. When the mode depth is 10 μm or more, the air release property can be secured when the pressure-sensitive adhesive sheet roll is produced using the obtained release paper. Moreover, when the mode depth is 140 μm or less, a decrease in the adhesive strength of the pressure-sensitive adhesive can be suppressed, and the appearance after adhesion to the adherend can be favorably maintained.

The shape of the recess S _Y in the horizontal cross section cut at a height of 10μm from the bottom alpha _Y of the concavo-convex structure Y is an equilateral triangle, square, regular polygonal or modifications, such as a regular hexagon (such as a rectangle or an isosceles triangle) May be selected, and may be circular or elliptical, but a 2n square (n is a positive integer) is particularly preferable.
Incidentally, the horizontal cross section cut at a height of 10μm from the bottom alpha _Y of the concavo-convex structure Y is a plane containing the reference line L _Y shown in FIG.

Release paper 10 of the present invention is characterized in that each of the convex portions T _Y constituting the concavo-convex structure Y has no recess H _Y.
The "recess H _Y" in the present invention, there is conversion point, the slope of changes from negative to positive, the shift conversion point height difference .DELTA.G _Y is 5μm or more and the top of the convex portion T _Y having a shift conversion point It is a region from the front and back to the portion where the inclination is negative to the portion where the inclination is positive, and the concept is the same as that of the “recessed portion H _X ”.

Release paper 20 of the present invention does not have the respective convex portions T _Y depression portion H _Y constituting the concavo-convex structure Y, until the adhesive is in the recess S _Y when an adhesive was applied to a release layer Easy to penetrate evenly. Therefore, it is considered that a uniform uneven structure is transferred to the pressure-sensitive adhesive layer, and the transparency of the pressure-sensitive adhesive layer can be maintained well.
Incidentally, the presence or absence of deepening H _Y is an uneven structure was measured with a laser microscope in the same manner as in the measurement method of the modal depth described above can be confirmed from the obtained cross-sectional image.

The material which comprises the release paper 20 of this invention can be suitably selected according to the use of release paper.
The thermoplastic resin constituting the release paper base material 21, and the thermoplastic resin layer A _Y, release paper substrate described in the first embodiment, and the same ones as the thermoplastic resin layer A _X like.
Further, the release paper substrate 21 may have a single layer structure or a multilayer structure. Examples of the release paper substrate having a multilayer structure include a laminate obtained by laminating an anti-curl agent layer and a sealing undercoat layer on the above-described plastic film or paper.

The thickness of the release paper substrate 21 is preferably 7 to 500 μm, more preferably 30 to 200 μm, and still more preferably 50 to 170 μm. If the thickness of the release paper substrate 11 is 7 μm or more, even when forming the minimum uneven structure Y in which the mode pitch and mode depth are the minimum values within the above range, the lamination process can be performed stably. Etc., and the concavo-convex structure Y can be easily formed. Moreover, if thickness is 500 micrometers or less, a release paper can be manufactured efficiently from a viewpoint of cost reduction by the processing speed at the time of manufacturing a release paper, the winding length of a release paper, the application quantity of resin, etc.
The thickness of the thermoplastic resin layer _AY is preferably 10 to 160 μm, more preferably 15 to 80 μm, and still more preferably 20 to 50 μm. When the thickness of the thermoplastic resin layer _AY is 10 μm or more, the laminate can be stably laminated even when the minimum uneven structure Y is formed such that the mode pitch and mode depth are the minimum values within the above range. Processing etc. can be given and the uneven structure Y can be formed easily. If the thickness is 160 μm or less, the release paper can be efficiently produced from the viewpoint of cost reduction due to the processing speed when producing the release paper, the winding length of the release paper, the amount of resin applied, and the like.

Examples of the release agent constituting the release layer _BY include the same release agents as those described in the first embodiment.
The thickness of the release layer _BY is preferably 0.1 to 5.0 g / m ² in terms of dry mass, more preferably 0.3 to 3.0 g / m ² , and 0.5 to 2 More preferably, it is 0.0 g / m ² . When the dry mass is 0.1 g / m ² or more, the release agent can be applied uniformly, and the release force can be controlled appropriately. Moreover, if dry mass is 5.0 g / m < ² > or less, a release paper can be manufactured efficiently from a viewpoint of cost reduction by the application speed of a release agent, the application amount of a release agent, and the like.

The release paper 20 of the present invention is suitable for use as a pressure-sensitive adhesive sheet for double-sided adhesion because the concavo-convex structure is formed on both sides. In particular, peel force in respect sensitive adhesive layer constituting the adhesive sheet, the release force of the release layer B _X side surface of the release paper 20 (the surface of the release paper), the peeling layer B _Y side surface (back surface of the release paper) And are preferably different. The difference in the peel force is preferably 1.2 to 10.0 times that of the smaller peel force and more preferably 1.5 to 3.0 times that of the smaller peel force.
The peeling force can be adjusted by changing the type of the release agent, the thickness of the release layer, the shape of the concavo-convex structure, and the like.

(Manufacturing method of release paper)
The release paper 20 shown in FIG. 5 can be manufactured as follows, for example.
First, as in the case of producing the release paper of the first embodiment, the first and second steps were carried out, on one surface of a release paper substrate 21, the thermoplastic resin layer A _X And a release layer _BX is formed.
Next, after the second step, the second thermoplastic resin is further applied on the other surface of the release paper base material 21 and immediately has a pressing roll with a flat surface and a concavo-convex structure Y ′ on the surface. Heat having a concavo-convex structure Y on the other surface of the release paper substrate 21 by passing between the cooling rolls so that the surface coated with the second thermoplastic resin is in contact with the cooling roll. to form a laminate M _Y of the thermoplastic resin layer a _Y are laminated (the more the third step.).

The third step may be performed in the same manner as the first step as shown in FIG. In the third step, conditions such as the pressure of the pressing roll 13, the resin temperature, and the processing speed are the same as those in the first step.
The uneven structure Y ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure X is a structure in which the uneven structure Y ′ is inverted. The mode pitch and mode height of the concavo-convex structure Y ′ are values measured in the same manner as the mode pitch and mode height of the concavo-convex structure Y.

Then, the thermoplastic resin layer A _Y of the stack M _Y obtained in the third step, on the surface irregular structure Y is formed, so as to hold the uneven structure Y, the second release agent It is applied to form a release layer _BY (the above is the fourth step) to obtain a release paper.

In the fourth step, as long as the second release agent can be applied so as to maintain the concavo-convex structure Y, the application conditions are not particularly limited, but the application amount of the second release agent is 0.1 to 2.0 g / m. ² is preferable, and the coating speed is preferably ² to 500 m / min, more preferably 10 to 300 m / min, and still more preferably 10 to 150 m / min.
Further, in the fourth step, in order to apply the second release agent so as to hold the concavo-convex structure Y, for example, a horizontal cross section cut at a height of 10 μm from the lowest α _Y of the concavo-convex structure Y shown in FIG. for recess S _Y shape 2n square (n is a positive integer) in, as shown in FIG. 4, one diagonal K _Y connecting the vertex facing the 2n square (rectangle) is, in the fourth step of so as to be parallel to the conveying direction of the laminate M _Y, in the third step, it is preferable to form the uneven structure Y on the surface of the thermoplastic resin layer a _Y.
Thus, the uniform release agent in the recess S _Y is likely to penetrate, while uneven structure XY retention of the thermoplastic resin layer A _Y, to form a peeling layer B _Y on the thermoplastic resin layer A _Y.

According to the release paper manufacturing method of the present invention, since the concavo-convex structure can be formed before the solidification of the thermoplastic resin is completed, it is easy to ensure the escape space of the volume corresponding to the concave portion. Therefore, it is difficult for the peripheral edge of the concave portion to be raised, and the concavo-convex structure of the sectional view as shown in FIG. 5 can be easily formed on both surfaces of the release paper.
Therefore, if it is this invention, the release paper suitable for the adhesive sheet for double-sided adhesion can be manufactured easily.

By the way, in the conventional method of embossing release paper with male and female embossing rolls, the uneven structure formed on the front surface and the back surface is in the relationship between the key and the keyhole, so that the uneven structure having the same shape is formed. Therefore, it is difficult to adjust the peeling force with the shape of the concavo-convex structure.
In addition, as described in Patent Documents 3 and 4, in the method of forming an uneven structure using an elastic roll having a flat surface and a male embossing roll, a resin layer in which a thermoplastic resin is solidified or a release layer is used. Since the concavo-convex structure is formed, it is necessary to press the embossing roll with a high pressure. Therefore, when forming the concavo-convex structure on the back surface of the release paper, the elastic roll hits the surface formed with the concavo-convex structure with high pressure, and the concavo-convex structure formed on the surface of the release paper is crushed by the elastic roll, Due to the deformation of the shape, it was difficult to form a concavo-convex structure on both sides of the release paper.

However, if it is the manufacturing method of the release paper of this invention, the shape of the uneven structure X ′ and Y ′ on the surface of the cooling roll used in the first step and the third step (mode pitch, mode height, etc.) By changing, the concavo-convex structure formed on the front and back surfaces of the release paper can be easily changed. Therefore, not only by changing the type of release agent and the thickness of the release layer, but also by changing the shape of the concavo-convex structure, the release force on the front and back surfaces of the release paper can be adjusted.
Further, according to the present invention, since the concavo-convex structure is formed before the solidification of the thermoplastic resin is completed, the pressure conditions in the first step and the third step can be set relatively low. Therefore, when the uneven structure Y is formed on the back surface of the release paper, the uneven structure X can be reduced from being crushed by the press roll even if the press roll comes into contact with the surface on which the uneven structure X is formed. Therefore, since the shape of the concavo-convex structure X can be prevented from being deformed, a pressure-sensitive adhesive sheet having sufficient air bleeding properties can be obtained.

[Adhesive sheet]
<First embodiment: for single-sided bonding>
One Embodiment of the adhesive sheet of this invention is described.
FIG. 7A shows an example of the pressure-sensitive adhesive sheet of the present embodiment. Fig.7 (a) is typical sectional drawing for showing an example of the cross-section of the adhesive sheet 30 of this invention. The pressure-sensitive adhesive sheet 30 is for single-sided adhesion, and the release paper 10 of the first embodiment described above and the pressure-sensitive adhesive sheet main body 33 provided with the pressure-sensitive adhesive layer 32 on one side of the pressure-sensitive adhesive sheet substrate 31 The release layer B _X and the pressure-sensitive adhesive layer 32 of the pressure-sensitive adhesive sheet body 33 are laminated inside.

As the pressure-sensitive adhesive sheet substrate 31, a known support in the pressure-sensitive adhesive sheet field such as papers and films can be used. For example, examples of paper supports include glassine paper, cast coated paper, art paper, coated paper, and high-quality paper. In addition, as a support for films, various polymer films such as polypropylene, polyethylene, polyethylene terephthalate, and vinyl chloride can be used. It is appropriately selected depending on. Among these, polyethylene terephthalate is preferable in terms of heat resistance.
A laminate in which at least one coating layer is provided on one side or both sides of these supports can also be used as the surface substrate.

As the pressure-sensitive adhesive sheet substrate 31, one having a void portion at least in part is particularly preferable. Since the surface base material having a void portion at least in part has cushioning properties per se, the surface of the surface base material is used, for example, when printing on the surface base material or when the surface of the adherend is not flat. In addition, unevenness such as printing marks is difficult to be produced, and the appearance of the pressure-sensitive adhesive sheet is excellent in smoothness.
Here, the “surface substrate having a void portion at least in part” means the whole or a part of the support (for example, the inside), or the support and / or the coating layer of the laminate as described above. At least one layer has voids such as a foamed part and a porous part. Examples of the support having such a void include synthetic paper, foamed PET, and foamed PP.

  The thickness of the surface substrate is preferably in the range of 5 to 400 μm. Among them, those having a thickness of 50 μm or more are preferable since there is almost no print mark when printed.

The pressure-sensitive adhesive layer 32 is composed of a pressure-sensitive adhesive and other optional components as necessary.
The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 32 is not particularly limited as long as desired adhesive strength and storage elastic modulus can be obtained, such as rubber-based, acrylic-based, vinyl ether-based, urethane-based, etc. Any adhesive can be used. Among these, an acrylic pressure-sensitive adhesive is preferable because it is excellent in weather resistance, transparency, and the like and can be used for a wide range of applications.
Examples of the acrylic pressure-sensitive adhesive include UV curable type, EB curable type, emulsion type, solvent type, hot melt type, etc. In the present invention, any type can be used, but in terms of transparency and quality, it is a solvent. Mold adhesives are preferred.

Examples of other optional components include adhesive microspheres, thickeners, pH adjusters, antifoaming agents, antiseptic / antifungal agents, pigments, inorganic fillers, stabilizers, wetting agents, wetting agents and the like.
Further, the adhesive layer 32 can contain a tackifier in order to change the tensile speed dependency of the adhesive force or to improve the adhesion to the olefin resin. Examples of tackifiers include rosin resins, terpene resins, aliphatic petroleum resins, aromatic petroleum resins, hydrogenated petroleum resins, styrene resins, alkylphenol resins, etc., because they have good adhesion to polyolefins. A rosin resin is preferred. Examples of the rosin resin include rosin, polymerized rosin, hydrogenated rosin, rosin ester, and hydrogenated rosin ester.
Furthermore, a surfactant may be added in order to improve the wetting (familiarity) with the cleaning water within a range not impairing the object of the present invention.

The thickness of the adhesive layer 32, by dry weight, is preferably from 10 to 200 g / ^{m 2,} more preferably from 15 to 100 / ^{m 2,} further preferably 20 to 60 g / ^{m 2} . If dry mass is 10 g / m < ² > or more, the adhesiveness of the adhesive layer 32 is fully securable. Moreover, if the dry mass is 200 g / m ² or less, the pressure-sensitive adhesive layer 32 does not become unnecessarily thick, and thus the cost can be reduced.

(Production method)
The adhesive sheet 30 shown to Fig.7 (a) can be manufactured as follows, for example.
Adhesive on the release layer B _X release paper 10, and optionally coating a coating solution containing other optional ingredients and a solvent (pressure-sensitive adhesive layer coating solution), dried to form a pressure-sensitive adhesive layer 32 After having made it, the adhesive sheet 30 is manufactured by the method of bonding the adhesive layer 32 and the adhesive sheet base material 31 together.
The coating amount of the pressure-sensitive adhesive layer coating solution is about 10 to ²⁰⁰ g / m ² in terms of dry mass. If the coating amount is less than 10 g / m ² , the adhesive performance of the resulting pressure-sensitive adhesive sheet may be insufficient, and if the coating amount exceeds 200 g / m ² , the pressure-sensitive adhesive may protrude significantly or the cost may be low. It becomes unpreferable because it becomes high.
The apparatus for applying the coating solution for the adhesive layer is not particularly limited, and known coating machines such as a roll coater, knife coater, bar coater, slot die coater, air knife coater, gravure coater, vario gravure coater, curtain coater, etc. Can be used.

  Thereby, the adhesive sheet 30 in which the uneven structure X of the release paper 10 is transferred to the surface of the adhesive layer 32 is obtained.

The adhesive sheet main body 33 and the release paper 10 can be bonded using a NIP method using a metal roll and a rubber roll, a gap calendar, or the like.
When using the NIP system, the rubber roll is preferably heat resistant, and the NIP pressure is preferably about 5 to 50 N / cm.

The method for producing the pressure-sensitive adhesive sheet 30 is not limited to the above-described method. For example, the pressure-sensitive adhesive layer coating liquid is applied and dried on one surface of the pressure-sensitive adhesive sheet substrate 31, and the pressure-sensitive adhesive layer 33 is provided. An adhesive sheet main body 33 is obtained. Next, the pressure-sensitive adhesive sheet 30 is bonded by bonding the pressure-sensitive adhesive sheet body 33 and the release paper 10 so that the pressure-sensitive adhesive layer 32 of the pressure-sensitive adhesive sheet body 33 and the release layer _BY of the release paper 10 of the present invention are inside. It can also be manufactured.

PSA sheet 30 obtained in this way, because of the use of release paper 10 of the present invention uniformly easily penetrate into adhesive recess S _X when an adhesive was applied to a release layer on the B _X . Therefore, since the uneven structure X on the surface of the release paper 10 is uniformly transferred to the pressure-sensitive adhesive layer 32, the transparency of the pressure-sensitive adhesive layer 32 can be maintained well. Therefore, even if the pressure-sensitive adhesive sheet 30 produced using a transparent film or the like as the pressure-sensitive adhesive sheet substrate 31 is attached to the adherend, the color or pattern of the adherend is not easily blurred.

When using the adhesive sheet 30 of the present embodiment, as shown in FIG. 7 (b), and peeled off between the peel layer B _X and the adhesive layer 32 of the release paper 10 (i.e., the release paper 10 After peeling), the exposed surface 32a of the pressure-sensitive adhesive layer 32 is adhered to the adherend.
As an adherend, for example, an optical member (for example, an antireflection body, a retardation plate, a diffusion plate, etc.), a member having a mirror surface (for example, a glass substrate, a resin substrate, etc.), an electrical member, a poster, a sticker, an automobile interior material, a board And wallpaper base materials.

<Second embodiment: for double-sided bonding>
FIG. 8A shows another example of the pressure-sensitive adhesive sheet of the present embodiment. Fig.8 (a) is typical sectional drawing for showing an example of the cross-section of the adhesive sheet 40 of this invention. The pressure-sensitive adhesive sheet 40 is for double-sided adhesion, and has two release papers 10 (the release paper 10 of the first embodiment described above) and a pressure-sensitive adhesive layer 41, and the two release papers 10 have the pressure-sensitive adhesive layer 41. It is laminated to the release layer B _X as an inner via. Here, one of the two release papers 10 is a “first release paper 10” and the other is a “second release paper 10 ′”.
Moreover, the adhesive sheet 40 differs in the peeling force with respect to the adhesive layer 41 of the 1st release paper 10 and 2nd release paper 10 '.

The pressure-sensitive adhesive layer 41 is composed of a pressure-sensitive adhesive and other optional components as necessary.
Examples of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 41 and other optional components include those similar to the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 32 described in the first embodiment and other optional components.
Moreover, you may add a tackifier and surfactant to the adhesive layer 41 similarly to the adhesive layer 32 demonstrated in 1st Embodiment.
Furthermore, the pressure-sensitive adhesive layer 41 may have a core layer (not shown). The core layer has a structure in which, for example, two or more layers of non-woven fabric, film, paper, and the like are bonded together, and has a delamination surface. The thickness of the middle core layer is preferably 5 to 100 μm, and more preferably 10 to 30 μm.

The thickness of the adhesive layer 41 on a dry weight, is preferably from 10 to 200 g / ^{m 2,} more preferably from 15 to 100 / ^{m 2,} further preferably 20 to 60 g / ^{m 2} . If dry mass is 10 g / m < ² > or more, the adhesiveness of the adhesive layer 41 is fully securable. Moreover, if dry mass is 200 g / m < ² > or less, the protrusion of an adhesive can be suppressed.

(Production method)
The adhesive sheet 40 shown to Fig.8 (a) can be manufactured as follows, for example.
First, the first release paper 10 peeled layer B _X of the pressure-sensitive adhesive layer coating liquid coated, and dried to form a pressure-sensitive adhesive layer 41.
The coating amount of the pressure-sensitive adhesive layer coating solution is about 10 to ²⁰⁰ g / m ² in terms of dry mass. If the coating amount is less than 10 g / m ² , the adhesive performance of the resulting pressure-sensitive adhesive sheet may be insufficient, and if the coating amount exceeds 200 g / m ² , the pressure-sensitive adhesive may protrude or the cost may be high. It is not preferable.
Examples of the apparatus for applying the adhesive layer coating liquid include the same apparatus as the apparatus for applying the adhesive layer coating liquid described in the first embodiment.
In the case of providing a center core layer to the adhesive layer 41, applying an adhesive layer coating solution on the release layer B _X of the first release paper 10, after drying, the material constituting the central core layer Adhesive layer having an intermediate core layer by pasting the intermediate core layer using a known laminating method or an adhesive bonding method, and then applying and drying an adhesive layer coating solution on the intermediate core layer. 41 is formed.

Next, the pressure-sensitive adhesive layer 41 and the second release paper 10 ′ are bonded so that B ′ _{X of} the second release paper 10 ′ is in contact with the pressure-sensitive adhesive layer 41.
Thereby, the adhesive sheet 40 by which the uneven structure X of the 1st release paper 10 and 2nd release paper 10 'was transcribe | transferred on both surfaces of the adhesive layer 41 is obtained.

The pressure-sensitive adhesive layer 41 and the second release paper 10 can be bonded using a NIP method using a metal roll and a rubber roll, a gap calendar, or the like.
When using the NIP system, the rubber roll is preferably heat resistant, and the NIP pressure is preferably about 5 to 50 N / cm.

Adhesive sheet 40 obtained in this way, because of the use of release paper 10 of the present invention, uniformly easily penetrate into adhesive recess S _X when an adhesive was applied to a release layer on the B _X . Therefore, since the uneven structure X on the surface of the release paper 10 is uniformly transferred to the pressure-sensitive adhesive layer 41, the transparency of the pressure-sensitive adhesive layer 41 can be maintained well. Therefore, even if the pressure-sensitive adhesive sheet 40 for double-sided adhesion is attached to a transparent adherend, the color or pattern of the adherend is not easily blurred.

The adhesive sheet 40 of this embodiment is used as follows. In the present embodiment, it is assumed that the peeling force for the pressure-sensitive adhesive layer 41 is smaller for the first release paper 10 than for the second release paper 10 ′.
First, as shown in FIG. 8 (b), a release layer B _X of the first release paper 10, is peeled off between the adhesive layer 41 (i.e., by peeling the first release sheet 10) The exposed surface 41a of the pressure-sensitive adhesive layer 41 is attached to the first adherend.
Next, as shown in FIG. 8C, in the state where the exposed surface 41a of the pressure-sensitive adhesive layer 41 is adhered to the first adherend 42, the release layer B ′ _{X of} the second release paper 10 ′, The adhesive layer 41 is peeled off (that is, the second release paper 10 ′ is peeled) to expose the other exposed surface 41b of the adhesive layer 41, and the exposed surface 41b is exposed to the second surface. Stick the kimono.

Examples of the first adherend and the second adherend include the same adherends as those described in the first embodiment.
In addition, when the adhesive layer 41 has a core layer, after bonding together the 1st to-be-adhered body and the 2nd to-be-adhered body via the adhesive sheet 40, the peeling surface of a core layer is as needed. The first adherend and the second adherend can be peeled off.

[Adhesive sheet roll]
<Third embodiment: for double-sided bonding>
FIG. 9A shows an example of the pressure-sensitive adhesive sheet roll of the present embodiment. Fig.9 (a) is typical sectional drawing for showing an example of the cross-section of the adhesive sheet winding body 50 of this invention. This pressure-sensitive adhesive sheet roll 50 is for double-sided adhesion, and has a pressure-sensitive adhesive sheet 52 comprising the release paper 20 of the second embodiment described above and a pressure-sensitive adhesive layer 51.
The release paper 20 constituting the pressure-sensitive adhesive sheet roll 50 is different in the peeling force for the pressure-sensitive adhesive layer 51 on the surface on the peeling layer B _X side and the peeling force for the pressure-sensitive adhesive layer 51 on the surface on the peeling layer _BY side. In the present embodiment, the release force for the pressure-sensitive adhesive layer 51 is intended surface of the release layer B _X side is smaller than the surface of the release layer B _Y side.

The pressure-sensitive adhesive sheet roll 50 is provided with a pressure-sensitive adhesive layer 51 on the surface of the release layer _BY of the release paper 20 opposite to the release paper base 11.
Further, the pressure-sensitive adhesive sheet wound body 50, the adhesive sheet 52, wound so that the adhesive layer 51 on the inside, the adhesive layer 51 is adhered to the release layer B _X.

The pressure-sensitive adhesive layer 51 is composed of a pressure-sensitive adhesive and other optional components as necessary.
Examples of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 51 and other optional components include those similar to the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 32 and other optional components described in the first embodiment.
Further, like the pressure-sensitive adhesive layer 32 described in the first embodiment, a tackifier, a surfactant, a crosslinking agent, a plasticizer, and the like may be added to the pressure-sensitive adhesive layer 51.
Furthermore, the pressure-sensitive adhesive layer 51 may have a core layer (not shown). Examples of the core layer include the same core layer as described in the second embodiment. The thickness of the middle core layer is preferably 5 to 100 μm, and more preferably 10 to 30 μm.

The thickness of the adhesive layer 51, by dry weight, is preferably from 10 to 200 g / ^{m 2,} more preferably from 15 to 100 / ^{m 2,} further preferably 20 to 60 g / ^{m 2} . If dry mass is 10 g / m < ² > or more, the adhesiveness of the adhesive layer 51 is fully securable. Moreover, if dry mass is 200 g / m < ² > or less, the protrusion of an adhesive can be suppressed.

(Production method)
The pressure-sensitive adhesive sheet roll 50 shown in FIG. 9A can be manufactured, for example, as follows.
First, the adhesive layer coating liquid is applied to the process release sheet and dried to form the adhesive layer 51.
The coating amount of the pressure-sensitive adhesive layer coating solution is about 10 to ²⁰⁰ g / m ² in terms of dry mass. If the coating amount is less than 10 g / m ² , the adhesive performance of the resulting pressure-sensitive adhesive sheet may be insufficient, and if the coating amount exceeds 200 g / m ² , the pressure-sensitive adhesive may protrude or the cost may be high. It is not preferable.
Examples of the apparatus for applying the adhesive layer coating liquid include the same apparatus as the apparatus for applying the adhesive layer coating liquid described in the first embodiment.
In addition, when providing a core layer in the adhesive layer 51, after apply | coating and drying the coating liquid for adhesive layers on a process peeling sheet, the material which comprises a core layer is based on a well-known lamination method or an adhesive agent. The core layer is bonded using a bonding method or the like, and then the pressure-sensitive adhesive layer coating solution is further applied onto the core layer and dried to form the pressure-sensitive adhesive layer 51 having the core layer.

Subsequently, after bonding the adhesive layer 51 on the process release paper and the release layer _BY of the release paper 20, the process release sheet is peeled off, and the adhesive layer 51 is formed on the release layer _BY side surface of the release paper 20. Is provided.
Thereby, the adhesive sheet 52 in which the uneven structure Y of the release paper 10 is transferred to the surface of the adhesive layer 51 is obtained.

Next, the adhesive sheet 52 is wound so that the adhesive layer 51 is inside the release paper 20.
Thereby, the pressure-sensitive adhesive sheet roll 50 in which the uneven structure X of the release paper 10 is transferred to the other surface of the pressure-sensitive adhesive layer 51 is obtained.

The pressure-sensitive adhesive layer 51 and the release paper 20 can be bonded using a NIP method using a metal roll and a rubber roll, a gap calendar, or the like.
When using the NIP system, the rubber roll is preferably heat resistant, and the NIP pressure is preferably about 5 to 50 N / cm.

Since the pressure-sensitive adhesive sheet roll 50 thus obtained uses the release paper 20 of the present invention, the pressure-sensitive adhesive easily penetrates uniformly into the recesses S _X and S _Y of the release paper. Therefore, since the uneven structure X and the uneven structure Y on the surface of the release paper 10 are uniformly transferred to both surfaces of the adhesive layer 51, the transparency of the adhesive layer 51 can be maintained well. Therefore, even if the pressure-sensitive adhesive sheet roll 50 for double-sided adhesion is attached to a transparent adherend, the color or pattern of the adherend is not easily blurred.

The pressure-sensitive adhesive sheet roll 50 of the present embodiment is used as follows.
First, as shown in FIG. 9 (b), a release layer B _X of release paper 20, is peeled off between the adhesive layer 51, feeding an adhesive sheet 52 from the pressure-sensitive adhesive sheet wound body 50, the pressure-sensitive adhesive layer The exposed surface 51a of 51 is stuck to the first adherend.
Next, as shown in FIG. 9C, the release layer _BY of the release paper 20, the adhesive layer 51, and the exposed surface 51 a of the adhesive layer 51 are attached to the first adherend 53. The other exposed surface 51b of the pressure-sensitive adhesive layer 51 is exposed, and the second adherend is adhered to the exposed surface 51b.

Examples of the first adherend and the second adherend include the same adherends as those described in the first embodiment.
In addition, when the adhesive layer 51 has a core layer, after bonding together the 1st to-be-adhered body and the 2nd to-be-adhered body via the adhesive sheet winding body 50, as needed, a core layer layer The first adherend and the second adherend can be peeled off by peeling the release surface.

[Example 1]
<Preparation of release paper>
On one side of “SPE110” (thickness: 118 μm) manufactured by Oji Specialty Paper Co., Ltd., a polyethylene resin (“Novatech LC607K” manufactured by Nippon Polyethylene Co., Ltd.) was laminated as a first thermoplastic resin using a T-die extruder. Immediately, the first thermoplastic resin is placed between a pressing roll having a flat surface and a water-cooled cooling roll having a concavo-convex structure X ′ (mode pitch: 420 μm, mode height is 35 μm) on the surface. by passing such coated surface is brought into contact with the cooling roll, on a release paper substrate, uneven structure thermoplastic resin layer a _X with X _(modal pitch: 415μm, modal depth: 30 [mu] m) is laminated a laminate was formed M _X was (first step).
In the first step, the pressure of the pressing roll was 40 N / cm, the resin temperature of the T die part was 330 ° C., and the processing speed was 10 m / min.

Thereafter, the other surface (back side) of “SPE110” is similarly laminated with the first thermoplastic resin by a T-die extruder, and immediately, a pressing roll having a flat surface and a water-cooling type cooling roll having a flat surface. And the surface of the release paper base that is coated with the first thermoplastic resin after the first step so that the surface is in contact with the cooling roll, and the resin layer (thickness: 24 μm) was formed. In this example, the resin layer thus formed and “SPE110” were used as the release paper base material.
The pressure of the pressing roll when forming the resin layer was 85 N / cm, the resin temperature of the T die part was 330 ° C., and the processing speed was 150 m / min.

Next, a coating solution in which silicone (“LTC-403A” manufactured by Toray Dow Corning Co., Ltd.) is diluted with toluene so as to have a concentration of 5% by mass is prepared as a first release agent. the thermoplastic resin layer a _X of the laminate M _X a, on the surface irregular structure X is formed so as to hold the uneven structure X, is applied, the peeling layer B _{X (dry} weight: 0.1 g / M ² ) (second step), and a release paper as shown in FIG. 1 was obtained.
In the second step, the application speed of the first release agent was 2 m / min.

Incidentally, uneven structure X is square shape of the recess S _X in the horizontal cross section cut at a height of 10μm from the bottom alpha _X of the concavo-convex structure X shown in FIG. 2, as shown in FIG. 3, the quadrangle In the first step, the concavo-convex structure X is formed on the surface of the thermoplastic resin layer A _X so that one of the diagonal lines K _X connecting the opposing vertices is parallel to the transport direction of the laminate M _X in the second step. Formed.

(Measurement 1: Measurement of the most frequent pitch)
First, on the surface where the concavo-convex structure X exists, a square region having a side of about 5 mm was randomly extracted, and an image measured with a laser microscope (“VK-8500 type” manufactured by Keyence Corporation) was obtained. The conditions for measurement with a laser microscope were a lens magnification of 200 times and a measurement pitch of 420 μm.
Subsequently, the waveform of this image was separated by Fourier transform to obtain an FFT image (fast Fourier transform image).
Next, the distance from the zero-order peak to the primary peak in the profile of the FFT image was obtained. The reciprocal of the distance thus obtained was defined as the most frequent pitch in this region. Such processing was similarly performed for a total of 25 regions of the same area selected at random, and the most frequent pitch in each region was obtained. The average value of the most frequent pitches in the 25 regions thus obtained was defined as the most frequent pitch of the concavo-convex structure X. The results are shown in Table 1.

(Measurement 2: Measurement of the most frequent depth)
First, a cross section of the concavo-convex structure X obtained by Fourier transform with a laser microscope (“VK-8500 type” manufactured by Keyence Corporation) that can be observed in a non-contact type with respect to the surface of the release paper was obtained. In this section, the five regions of the square shape can be observed projections T _X (area of the square one side is 5 times the most frequent pitch of the concavo-convex structure X) selected at random, were measured with a laser microscope section I got an image. The conditions for measurement with a laser microscope were the same as those for the most frequent pitch.
Then, from this cross-sectional image was read five data D _X in the manner of FIG. That is, the _X 'top γ of _X' any protrusions T, the distance of the bottom alpha _'X of _X' concave S adjacent to _X 'which convex portion T and a D _X. Similarly, from a total of five laser microscope images, each five data were obtained for a total of 25 D _X.
Then, an equator direction profile of a two-dimensional Fourier transform image was created, and the data of the most frequent depth of the concavo-convex structure X was obtained from the reciprocal of the primary peak. The results are shown in Table 1.

(Measurement 3: confirmation of the presence or absence of the recess _{H X)}
First, in the same manner as in measurement 2, an image measured with a laser microscope was obtained.
Next, profile analysis was performed on the obtained image to obtain a cross-sectional image. From the obtained cross-sectional images, to confirm the presence or absence of the recess H _X. The results are shown in Table 1.

(Measurement 4: Measurement of surface roughness Ra and smoothness)
The surface of the release paper opposite to the side on which the thermoplastic resin layer _AX is laminated (the back side of the release paper) is roughened using an ultradeep shape measuring microscope (manufactured by Keyence Corporation, “VK-9500”). Ra was measured. Similarly, the smoothness was measured using a smoothness measuring instrument (Asahi Seiko Co., Ltd., “Oken type smoothness meter, model KB2S”). The results are shown in Table 1.

<Production of adhesive sheet>
First, on the surface of the release layer B _X release paper previously obtained pressure-sensitive adhesive (Toyo Ink Mfg. Co., "BPS-8170") was applied and dried to provide a pressure-sensitive adhesive layer, with a release paper An adhesive layer was obtained. The coating amount of the coating solution was 50 g / m ² in terms of dry mass.
Next, one side of a transparent adhesive sheet base material (“Lumirror S10”, manufactured by Toray Industries, Inc., thickness: 25 μm) and the adhesive layer with release paper were bonded together so that the release paper was on the inside. A pressure-sensitive adhesive sheet for adhesion was obtained.

(Evaluation 1: Evaluation of air bleeding property)
Peel off the release paper of the resulting adhesive sheet (dimensions: 10 cm x 10 cm square), lightly affix the adhesive sheet body to a highly smooth glass plate (dimensions: 20 x cm x 20 cm square), and then push out the air The state of air leakage when lightly pressed with a rubber roller (diameter: 5 cm, width: 15 cm) was visually evaluated as follows. The results are shown in Table 1.
○: No air remained.
Δ: A slight amount of air remained, but no blistering was observed.
X: Air remained and it became blistered.

(Evaluation 2: Evaluation of transparency)
The release sheet of the obtained pressure-sensitive adhesive sheet (dimension: 10 cm × 10 cm square) is peeled off, and the pressure-sensitive adhesive sheet main body is attached to an adherend (PET base material of JIS-C-2318). The transparency of the pressure-sensitive adhesive sheet was measured according to Standard: ISO5-2, using “DOT-5” manufactured by Color Research Laboratory, and the appearance was evaluated visually as follows. The results are shown in Table 1.
◯: The trace of the concavo-convex structure X of the release paper is thin and there is a sense of transparency.
(Triangle | delta): The trace of the uneven structure X of a release paper is transcribe | transferred by the matte tone.
X: Traces of the concavo-convex structure X of the release paper are transferred and uneven.

[Example 2]
<Preparation of release paper>
A release paper was prepared in the same manner as in Example 1. This is the first release paper.
Separately, in a second step, the silicone (manufactured by Dow Corning Toray Co., Ltd. as a first release agent, using a "LTC-450A", except that the dry mass was formed a release layer B _X so as to be 0.1μm, the A release paper was obtained in the same manner as in Example 1. This is the second release paper.

(Measurement)
In the same manner as in Example 1, the concavo-convex structure X of the obtained first release paper and second release paper was measured for the most frequent pitch, the most frequent depth, the surface roughness Ra, and the smoothness. to confirm the presence or absence of the part H _X. The results are shown in Table 1.

<Production of adhesive sheet>
First, the first release paper release layer B _X, adhesive (Toyo Ink Mfg. Co., "BPS-8170") was applied and dried to form an adhesive layer. The coating amount of the coating solution was 50 g / m ² in terms of dry mass.
Then, an adhesive layer and a second release paper, B _X of the second release paper laminated in contact with the adhesive layer to give an adhesive sheet for double-sided adhesive.

(Evaluation of air release properties)
The first release paper of the obtained pressure-sensitive adhesive sheet (dimension: 10 cm × 10 cm square) is peeled off, and the exposed surface of the pressure-sensitive adhesive layer is lightly attached to the first adherend (PET substrate of JIS-C-2318). It was. Next, the second release paper is peeled off, and the pressure-sensitive adhesive sheet body is lightly affixed to the second adherend (high smooth glass plate, dimensions: 20 × cm × 20 cm square), and then a rubber roller to push out the air (Diameter: 5 cm, width: 15 cm) was lightly pasted. Thereafter, the state of air loss was visually evaluated as follows. In addition, the evaluation result visually observed from the first adherend side is regarded as the evaluation of the air releasing property on the first release paper side, and the evaluation result visually observed from the second adherend side is the air releasing property on the second release paper side. It was evaluated. The results are shown in Table 1.
○: No air remained.
Δ: A slight amount of air remained, but no blistering was observed.
X: Air remained and it became blistered.

(Evaluation of transparency on the first release paper side)
The first release paper of the obtained pressure-sensitive adhesive sheet (dimension: 10 cm × 10 cm square) was peeled off, and the exposed surface of the pressure-sensitive adhesive layer was attached to an adherend (PET base material of JIS-C-2318). Next, the second release paper is peeled off, and the diffused light transparency meter (Murakami Co., Ltd.) with the other exposed surface of the adhesive layer (exposed surface of the adhesive layer on the second release paper side) exposed. The transparency of the pressure-sensitive adhesive sheet was measured according to Standard: ISO5-2, using “DOT-5” manufactured by Color Research Laboratory, and the appearance was evaluated visually as follows. The results are shown in Table 1.
○: Traces of the concavo-convex structure X of the first and second release papers are thin and transparent.
(Triangle | delta): The trace of the uneven structure X of the 1st and 2nd peeling paper is transcribe | transferred by the matte tone.
X: Traces of the concavo-convex structure X of the first and second release papers are transferred and uneven.

(Evaluation of transparency on the second release paper side)
The second release paper is peeled off so that the first release paper of the obtained pressure-sensitive adhesive sheet (dimension: 10 cm × 10 cm square) is not peeled, and the exposed surface of the pressure-sensitive adhesive layer is adhered to the adherend (JIS-C-2318). (PET substrate). Next, the first release paper is peeled off, and the transparency of the pressure-sensitive adhesive sheet is measured with the other exposed surface of the pressure-sensitive adhesive layer (the exposed surface of the pressure-sensitive adhesive layer on the first release paper side) exposed. Appearance was evaluated. The measurement of the transparency of the pressure-sensitive adhesive sheet and the appearance evaluation were performed in the same manner as the evaluation of the transparency on the first release paper side. The results are shown in Table 1.

[Example 3]
<Preparation of release paper>
In the same manner as in Example 1, the first step and the second step were performed, and the thermoplastic resin layer _AX and the release layer _BX were formed on one surface of the release paper substrate. However, no resin layer was formed as the outermost layer on the back side of the release paper substrate.
Next, after the second step, a polyethylene resin (“Novatec LC607K” manufactured by Nippon Polyethylene Co., Ltd.) is extruded and laminated as the second thermoplastic resin on the other surface of the release paper substrate, and the surface is immediately flattened. The surface on which the second thermoplastic resin is applied is a cooling roll between a pressing roll and a cooling roll having a concavo-convex structure Y ′ (mode pitch: 420 μm, mode height is 35 μm) on the surface. A laminated body in which a thermoplastic resin layer A _Y having a concavo-convex structure _Y (mode pitch: 415 μm, mode depth: 30 μm) is laminated on the other surface of the release paper base by passing it in contact. _MY was formed (third step).
In the third step, the pressure of the pressing roll was 40 N / cm, the resin temperature of the T die part was 330 ° C., and the processing speed was 10 m / min.

Separately, as a second release agent, a coating solution in which silicone (“LTC-450A” manufactured by Toray Dow Corning Co., Ltd.) is diluted with toluene so as to have a concentration of 5 mass% is prepared, and the coating solution is laminated. the thermoplastic resin layer a _Y of M _Y, on the surface irregular structure Y is formed, so as to hold the uneven structure Y, is applied, the peeling layer B _{Y (dry} weight: 0.1 [mu] m) formed (4th process) and the release paper as shown in FIG. 5 was obtained.
In the fourth step, the application speed of the second release agent was 100 m / min.

Incidentally, uneven structure Y is square shape of the recess S _Y in the horizontal cross section cut at a height of 10μm from the bottom alpha _Y of the concavo-convex structure Y shown in FIG. 6, as shown in FIG. 3, the quadrangle 1 diagonals K _Y connecting the vertices opposed, so as to be parallel to the conveying direction of the laminate M _Y in the fourth step, the third uneven structure on the surface of the thermoplastic resin layer a _Y in step Y Formed.

(Measurement)
In the same manner as in Example 1, the uneven structure of the release paper obtained X and irregular structure Y, and the modal pitch modal depth, surface roughness Ra, and the smoothness measurement, recessed portions H _X, H The presence or absence of _Y was confirmed. The results are shown in Table 1.

<Preparation of wound adhesive sheet>
First, a pressure-sensitive adhesive (manufactured by Toyo Ink Manufacturing Co., Ltd., “BPS-8170”) was applied to the process release sheet and dried to form a pressure-sensitive adhesive layer. The coating amount of the coating solution was about 50 g / m ² in terms of dry mass.
Next, after the pressure-sensitive adhesive layer on the process release paper and the release paper _BY of the release paper are bonded together, the process release sheet is peeled off, and the pressure-sensitive adhesive layer is provided on the surface of the release paper on the release layer _BY side. A sheet was obtained.
Next, the pressure-sensitive adhesive sheet was wound so that the pressure-sensitive adhesive layer was inside the release paper, and a pressure-sensitive adhesive sheet roll was obtained.

(Evaluation of air release properties)
Between the obtained pressure-sensitive adhesive sheet wound body peeling layer B _X and the adhesive layer of release paper is peeled off, feeding the pressure-sensitive adhesive sheet from the adhesive sheet wound body, a first of the exposed surface of the adhesive layer It was lightly affixed to a kimono (a PET substrate of JIS-C-2318). Next, the release layer _BY of the release paper and the pressure-sensitive adhesive layer are peeled off (the release paper is peeled off), and the pressure-sensitive adhesive sheet body is attached to the second adherend (highly smooth glass plate, size: 20 × cm). × 20 cm square). Then, it lightly affixed with the rubber roller (diameter: 5 cm, width: 15 cm) so that air might be extruded. Thereafter, the state of air loss was visually evaluated as follows. In addition, the evaluation result visually observed from the first adherend side is regarded as the evaluation of the air bleeding property on the uneven structure X side, and the evaluation result visually observed from the second adherend side is regarded as the evaluation of the air bleeding property on the uneven surface structure Y side. . The results are shown in Table 1.
○: No air remained.
Δ: A slight amount of air remained, but no blistering was observed.
X: Air remained and it became blistered.

(Evaluation of transparency on the uneven structure X side)
Between the obtained pressure-sensitive adhesive sheet wound body peeling layer B _X and the adhesive layer of release paper is peeled off, feeding the pressure-sensitive adhesive sheet from the adhesive sheet wound body, the exposed surface of the adhesive layer adherend ( JIS-C-2318 PET substrate). Subsequently, the release layer _{BY of the} release paper is peeled off from the pressure-sensitive adhesive layer (peeling the release paper), and the other exposed surface of the pressure-sensitive adhesive layer (exposed surface of the pressure-sensitive adhesive layer on the release layer _BY side) ) With a diffused light transparency meter (manufactured by Murakami Color Research Laboratory Co., Ltd., “DOT-5”) measured in accordance with the standard: ISO5-2, Further, the appearance was visually evaluated as follows. The results are shown in Table 1.
○: The traces of the concavo-convex structure X and Y of the release paper are thin, and there is a sense of transparency.
(Triangle | delta): The trace of the uneven structure X and Y of a release paper is transcribe | transferred by the matte tone.
X: Traces of the concavo-convex structure X and Y of the release paper are transferred and uneven.

(Evaluation of transparency on the uneven structure Y side)
Between the obtained pressure-sensitive adhesive sheet wound body peeling layer B _X and the adhesive layer of release paper is peeled off, feeding the pressure-sensitive adhesive sheet from the adhesive sheet wound body, further release paper release layer B _Y and a pressure-sensitive adhesive The layers were peeled off (the release paper was peeled off) so that both sides of the pressure-sensitive adhesive layer were exposed. Next, the exposed surface of the adhesive layer on the peeling layer _BY side was attached to an adherend (PET base material of JIS-C-2318). Release layer B With the exposed surface of the pressure-sensitive adhesive layer on the _X side exposed, the transparency of the pressure-sensitive adhesive sheet was measured, and the appearance was further evaluated. The measurement of the transparency of the pressure-sensitive adhesive sheet and the appearance evaluation were performed in the same manner as the evaluation of the transparency on the uneven structure X side. The results are shown in Table 1.

[Comparative Example 1]
<Preparation of release paper>
On one side of a release paper base (Oji Special Paper, “SPE110”, thickness: 118 μm), a polyethylene resin (Nippon Polyethylene, “Novatec LC607K”) is extruded and laminated as the first thermoplastic resin. to, on the release paper base material, the first thermoplastic resin layer a _{X (thickness:} 24 [mu] m) was formed a laminate M _X laminated.
Separately, as a first release agent, a coating solution in which silicone (“LTC403-A” manufactured by Toray Dow Corning Co., Ltd.) is diluted with toluene to a concentration of 8% by mass is prepared, and the coating solution is laminated. by coating the first thermoplastic resin layer _{a X} of M _X, peeling layer _{B X} (dry weight: 0.7 [mu] m) was formed.
Next, the first thermoplastic resin is applied between a pressing roll having a flat surface and a metal engraving roll having a concavo-convex structure X ′ (mode pitch: 420 μm, mode height: 65 μm) on the surface. The release paper having the concavo-convex structure X formed on the surface of the release paper on the side where the thermoplastic resin layer _AX and the release layer _BX are laminated is passed so that the surface is in contact with the metal engraving roll. Obtained.
In addition, the pressure of the pressure roll at the time of forming the uneven structure X was 85 N / cm, the resin temperature was 330 ° C., and the processing speed was 200 m / min.

(Measurement)
In the same manner as in Example 1, the uneven structure X of the resulting release paper, the modal pitch modal depth, surface roughness Ra, and the smoothness was measured to confirm the presence or absence of the recess H _X. The results are shown in Table 1.

<Production of adhesive sheet>
A single-sided adhesive sheet was prepared in the same manner as in Example 1 except that the release paper prepared in Comparative Example 1 was used. About the obtained adhesive sheet, it carried out similarly to Example 1, and evaluated air bleeding property and transparency. The results are shown in Table 1.

[Comparative Example 2]
<Preparation of release paper>
A release paper produced in the same manner as in Comparative Example 1 was produced. This is the first release paper.
Separately, silicone (Dow Corning Toray Co., Ltd. as the first release agent, using a "LTC-450A", except that the dry mass was formed a release layer B _X so as to be 0.7μm is in the same manner as in Comparative Example 1 A release paper was obtained, which was designated as a second release paper.

(Measurement)
In the same manner as in Example 1, the concavo-convex structure X of the obtained first release paper and second release paper was measured for the most frequent pitch, the most frequent depth, the surface roughness Ra, and the smoothness. to confirm the presence or absence of the part H _X. The results are shown in Table 1.

<Production of adhesive sheet>
A pressure-sensitive adhesive sheet for double-sided adhesion was produced in the same manner as in Example 2 except that the release paper produced in Comparative Example 2 was used. About the obtained adhesive sheet, it carried out similarly to Example 2, and evaluated air permeability and transparency of the 1st release paper side and the 2nd release paper side. The results are shown in Table 1.

[Comparative Example 3]
<Preparation of release paper>
In the same manner as in Comparative Example 1, a thermoplastic resin layer _AX and a release layer _BX were formed on one surface of a release paper substrate, and a concavo-convex structure X was formed with a metal engraving roll.
Next, a polyethylene resin is extruded and laminated as the second thermoplastic resin on the other surface of the release paper substrate, and the second thermoplastic resin layer A _Y (thickness: 24 μm) is formed on the release paper substrate. There was formed a laminate M _Y laminated.
Separately, as a second release agent, a coating solution in which silicone (“LTC-450A” manufactured by Toray Dow Corning Co., Ltd.) is diluted with toluene to a concentration of 8% by mass is prepared, and the coating solution is laminated. It is applied to the second thermoplastic resin layer _{a Y} of M _Y, peeling layer _{B Y} (dry weight: 0.7 [mu] m) was formed.

Next, the second thermoplastic resin is applied between a pressing roll having a flat surface and a metal engraving roll having a concavo-convex structure Y ′ (mode pitch: 420 μm, mode height is 65 μm) on the surface. The release paper having the concavo-convex structure Y formed on the surface of the release paper on the side where the thermoplastic resin layer _AY and release layer _BY are laminated is passed so that the surface is in contact with the metal engraving roll. Obtained.
In addition, the pressure of the pressure roll at the time of forming the uneven structure Y was 85 N / cm, the resin temperature was 330 ° C., and the processing speed was 100 m / min.

(Measurement)
In the same manner as in Example 1, the uneven structure of the release paper obtained X and irregular structure Y, and the modal pitch modal depth, surface roughness Ra, and the smoothness measurement, recessed portions H _X, H The presence or absence of _Y was confirmed. The results are shown in Table 1.

<Preparation of wound adhesive sheet>
A pressure-sensitive adhesive sheet for double-sided adhesion was produced in the same manner as in Example 3 except that the release paper produced in Comparative Example 3 was used. About the obtained adhesive sheet winding body, it carried out similarly to Example 3, and evaluated air permeability and transparency of the uneven structure X side and the uneven structure Y side. The results are shown in Table 1.

As is apparent from Table 1, obtained in the Examples, the release paper having no recess H _X, maintaining the air vent property, a pressure-sensitive adhesive sheet with a superior transparency adhesive layer, and adhesive A sheet roll was obtained.
In addition, the release paper obtained in Examples 1 and 2 had a flat surface on the side opposite to the side on which the thermoplastic resin layer _AX was laminated (the back side of the release paper). Therefore, even if the pressure-sensitive adhesive sheets were stacked, the pressure-sensitive adhesive sheet surface in contact with the back surface of the release paper could be maintained in a flat state.

On the other hand, obtained in Comparative Examples 1 and 2, the pressure-sensitive adhesive sheet produced with the release paper having a recess H _X, air vent property were inferior to those in Examples 1 and 2. Further, the transparency of the pressure-sensitive adhesive layer was low, and the trace of the concavo-convex structure X was transferred in a matte tone. Furthermore, in the release papers obtained in Comparative Examples 1 and 2, the surface opposite to the side on which the thermoplastic resin layer _AX was laminated (the back surface of the release paper) was not flat. Therefore, when the pressure-sensitive adhesive sheets are stacked, the uneven structure X of the release paper is easily transferred to the surface of the pressure-sensitive adhesive sheet in contact with the back surface of the release paper.
In addition, the release paper having the recesses H _X and H _Y obtained in Comparative Example 3 was uneven because the pressing roll pressed against the surface formed by the concavo-convex structure X with high pressure when forming the concavo-convex structure Y. Structure X was crushed and deformed. The pressure-sensitive adhesive sheet roll obtained from this release paper was easy to allow air to enter into the pressure-sensitive adhesive layer, and the air releasing property was inferior to that of Example 3. Further, the transparency of the pressure-sensitive adhesive layer was low, and the trace of the concavo-convex structure X was transferred in a matte tone.

It is typical sectional drawing for showing an example of the section structure of the release paper of the present invention. The surface of the release layer B _X in FIG. 1 is a cross-sectional image when measured with a laser microscope. The first step in the production process of the release paper of the present invention is an explanatory diagram showing a state of manufacturing the laminate M _X. In a method of manufacturing a release paper of the present invention, a diagonal line connecting the conveying direction of the laminate M _X in the second step, the shape of the concave portion S _X in the horizontal cross section of the concavo-convex structure X at the 2n square, the vertex facing is a diagram illustrating the relationship between K _X direction. It is typical sectional drawing for showing the other example of the section structure of the release paper of the present invention. It is a cross-sectional image when the surface of peeling layer _BY of FIG. 5 is measured with a laser microscope. (A) is typical sectional drawing for showing an example of the cross-sectional structure of the adhesive sheet of this invention, (b) is a figure explaining the usage method of the adhesive sheet shown to (a). (A) is typical sectional drawing for showing an example of the cross-sectional structure of the other example of the adhesive sheet of this invention, (b), (c) demonstrates the usage method of the adhesive sheet shown to (a). It is a figure to do. (A) is typical sectional drawing for showing an example of cross-sectional structure of the adhesive sheet winding body of this invention, (b), (c) is the usage method of the adhesive sheet winding body shown to (a). FIG. It is typical sectional drawing for showing an example of the cross-sectional structure of the conventional release paper. The surface of the release layer B _X in FIG. 10 is a cross-sectional image when measured with a laser microscope.

Explanation of symbols

10, 20: Release paper, 11, 21: Release paper substrate, 13: Press roll, 14: Cooling roll, 30, 40, 52: Adhesive sheet, 31: Adhesive sheet substrate, 32, 41, 51: Adhesive Layer, 33: pressure-sensitive adhesive sheet body, 50: pressure-sensitive adhesive sheet roll, A _X , A _Y : thermoplastic resin layer, B _X , B _Y : release layer, T _X , T _Y : convex portion, H _X , H _Y : Depression, α _X , α _Y : bottom, β _X , β _Y : reference point, L _X , L _Y : reference line, L _X1 , L _Y1 : point crossing the reference line with a positive slope, L _X2 , L _Y2 : Point crossing the reference line with a negative slope, C _X : Conversion point, ΔG _X , ΔG _Y : Height difference, γ _X , γ _Y : Top part, M _X , M _Y : Laminate, K _X , K _Y : diagonal line.

Claims (16)

A release paper for use in contact with the adhesive layer, on one surface of a release paper base material, the thermoplastic resin layer A _X and the peeling layer B _X are sequentially laminated,
In the thermoplastic resin layer _{A X} and the release layer _{B X} is the surface of the release paper side are stacked, the most frequent pitch 100 to 2000, modal depth comprises a concavo-convex structure X is 10～140Myuemu, A release paper, wherein each convex portion T _X constituting the concave-convex structure X does not have a hollow portion H _X.
However, the convex portion T _X, the reference in the cross-section image when measuring uneven structure X a laser microscope, a point away 10μm upwardly from the bottom when the depth direction of the uneven structure X and the vertical direction It is the upper part from the point crossing the reference line drawn in the direction perpendicular to the vertical direction through the reference point with a positive inclination from the point crossing with a negative inclination,
The recess H _X, inclination from the minus have conversion point turn positive, height difference .DELTA.G _X between the top of the convex portion T _X having a shift conversion points before and after the shift conversion point is 5μm or more, the inclination This is the area from the negative part to the positive part. Release layer B _X Is composed of a release agent selected from silicone resins, waxes, alkyd resins, alkyd-modified silicones, acrylic-modified silicones, fluororesins, and long-chain alkyl pendant release agents. The release paper according to 1. The release paper according to claim 1 or 2 , wherein the surface opposite to the side on which the thermoplastic resin layer _AX is laminated is flat. A thermoplastic resin layer _AY and a release layer _BY are sequentially laminated on the other surface of the release paper substrate, and the release on the side where the thermoplastic resin layer _AY and the release layer _BY are laminated. on the surface of the paper, the most frequent pitch 100 to 2000, modal depth comprises a concavo-convex structure Y is 10～140Myuemu, no respective protrusion _{T Y} depression portion _{H Y} constituting the uneven structure Y The release paper according to claim 1 or 2 , characterized in that.
However, the convex portion _TY is based on a point 10 μm away from the lowermost portion when the depth direction of the concavo-convex structure Y is set as the vertical direction in the cross-sectional image when the concavo-convex structure Y is measured with a laser microscope. It is the upper part from the point crossing the reference line drawn in the direction perpendicular to the vertical direction through the reference point with a positive inclination from the point crossing with a negative inclination,
The recess H _Y, inclination there is conversion point changes from negative to positive, the height difference .DELTA.G _Y between the top of the convex portion T _Y having a shift conversion points before and after the shift conversion point is 5μm or more, the inclination This is the area from the negative part to the positive part. Release layer B _Y Is composed of a release agent selected from silicone resins, waxes, alkyd resins, alkyd-modified silicones, acrylic-modified silicones, fluororesins, and long-chain alkyl pendant release agents. The release paper according to 4. The release paper as described in any one of Claims 1-3 and the adhesive sheet main body provided with the adhesive layer on the single side | surface of an adhesive sheet base material are the release layer of release paper, and the adhesive layer of an adhesive sheet main body. A pressure-sensitive adhesive sheet characterized by being laminated on the inside. A first release paper and a second release paper in which a thermoplastic resin layer and a release layer are sequentially laminated are laminated on one side of the release paper substrate with the release layer as an inner side through an adhesive layer. The first release paper and the second release paper are the release paper according to any one of 1 to 3, and the release force of the first release paper and the second release paper with respect to the pressure-sensitive adhesive layer. The pressure-sensitive adhesive sheet is characterized in that the two are different. And release paper according to claim 4 or 5, having a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer, pressure-sensitive adhesive sheet wound body, wherein a pressure-sensitive adhesive sheet is wound.
However, the release layer on the release layer B _X side surface of the release paper is different from the release force on the adhesive layer on the release layer _BY side surface, and the release layer having a large release force. It is assumed that the pressure-sensitive adhesive layer is provided on the top and is wound with the release layer having a small peeling force as the outside. A method for producing a release paper used in contact with an adhesive layer,
The first thermoplastic resin is applied on one surface of the release paper base, and immediately between the pressing roll having a flat surface and the cooling roll having the concavo-convex structure X ′ on the surface, the first by plane thermoplastic resin is applied is to pass so as to contact the chill roll, the formed on a release paper substrate, a laminate M _X of the thermoplastic resin layer a _X having an uneven structure X are laminated a first step, the thermoplastic resin layer a _X of the laminate M _X, on the surface irregular structure X is formed so as to hold the uneven structure X, by applying a first release agent peeling method for manufacturing release paper, characterized in that it comprises a second step of forming a layer B _X.
However, the uneven structure X ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure X is a structure in which the uneven structure X ′ is inverted. The first release agent is a release agent selected from silicone resins, waxes, alkyd resins, alkyd-modified silicones, acrylic-modified silicones, fluororesins, and long-chain alkyl pendant release agents. The method for producing a release paper according to claim 9. The shape of the recess S _X in a horizontal section cut at a height of 10 μm from the bottom of the concavo-convex structure X is a 2n square (n is a positive integer), and 1 of a diagonal line K _X connecting the opposing vertices of the 2n square. this is the second to be parallel to the conveying direction of the laminate M _X in step, claim 9 or 10, characterized by forming an uneven structure X on the surface of the thermoplastic resin layer a _X The manufacturing method of the release paper as described in any one of. The method for producing a release paper according to any one of claims 9 to 11, wherein the pressure of the pressing roll in the first step is 30 to 100 N / cm. After the second step, a second thermoplastic resin is further applied on the other surface of the release paper base, and immediately a pressing roll with a flat surface and a cooling roll having a concavo-convex structure Y ′ on the surface The thermoplastic resin layer having the concavo-convex structure Y on the other surface of the release paper base material by passing between the two surfaces of the release paper base so that the surface coated with the second thermoplastic resin contacts the cooling roll. a third step of forming a laminate M _Y where a _Y are laminated, the thermoplastic resin layer a _Y of the laminate M _Y, on the surface irregular structure Y is formed, to retain the uneven structure Y as described above, by applying the second release agent, any of the claim 9-12, wherein the peeling layer B _X, characterized in that it comprises a fourth step of forming a different separation layer B _Y peeling force A method for producing a release paper according to claim 1 .
However, the uneven structure Y ′ is a structure having a mode pitch of 100 to 2000 μm and a mode height of 10 to 140 μm, and the uneven structure Y is a structure in which the uneven structure Y ′ is inverted. The second release agent is a release agent selected from silicone resins, waxes, alkyd resins, alkyd modified silicones, acrylic modified silicones, fluororesins, and long chain alkyl pendant release agents. The method for producing a release paper according to claim 13. It said recess S _Y is 2n rectangular shape in horizontal cross section cut at a height of 10μm from the bottom of the uneven structure Y (n is a positive integer), and 1 diagonal K _Y connecting the vertex facing the said 2n square this is the fourth to be parallel to the conveying direction of the laminate M _Y in step claim 13 or 14, characterized by forming an uneven structure Y on the surface of the thermoplastic resin layer a _Y The manufacturing method of the release paper as described in any one of. The method for producing a release paper according to any one of claims 13 to 15, wherein the pressure of the pressing roll in the third step is 30 to 100 N / cm.

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