JP2000265128A - Production of adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing an adhesive sheet by which the tacky sheet capable of suppressing the deterioration of appearance properties due to mottling caused by contact of the back surface of a mold release paper with a coating film layer and good in the appearance properties can efficiently and stably be supplied when producing the tacky sheet having the coating film layer formed on one surface of a supporting substrate. SOLUTION: A adhesive mass layer and a mold release paper are laminated onto one surface of a supporting substrate and a coating material is then laminated onto the surface on the opposite side. A process paper having 10-200 g/50 mm release force after aging at 23 deg.C for 24 h is then laminated onto the surface of the resultant coating film layer after drying a solvent in the coating material to thereby produce an adhesive sheet when producing the tacky sheet having the coating film layer laminated onto the one surface of the supporting substrate and the adhesive mass layer and the mold release paper laminated onto the surface on the opposite side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an adhesive sheet used as a decorative marking film for outdoor and indoor advertising stickers and display stickers, and more particularly, to the back of a release paper in a production stage. Provided is a method for producing a pressure-sensitive adhesive sheet, which can suppress deterioration of appearance properties caused by transfer of the pressure-sensitive adhesive sheet to a coating film layer.

[0002]

2. Description of the Related Art Conventionally, in a decorative adhesive sheet, generally,
A substrate made of a vinyl chloride resin film is used. Depending on the purpose, the base material is colored by adding a pigment to the base material, or the base material is decorated by printing or painting. Further, a pressure-sensitive adhesive and / or a heat-sensitive adhesive suitable for the intended use are applied to one surface of the base material to form a pressure-sensitive adhesive layer. further,
In order to protect the pressure-sensitive adhesive layer in a product, a release material such as release paper is attached so as to cover the pressure-sensitive adhesive layer.

In use, an adhesive sheet is attached to an adherend after releasing the release paper. In the adhered pressure-sensitive adhesive sheet, the decorative effect is exhibited by the coloring of the substrate or by the printed layer or the coating layer formed on the surface of the substrate.

The decorative adhesive sheet as described above is used for signboards,
It is used to decorate various adherends such as advertising towers, vehicles such as automobiles and motorcycles, and motor boats. Therefore, a decorative adhesive sheet is required to have appropriate flexibility so that it can be attached to a three-dimensional curved surface.

However, in a pressure-sensitive adhesive sheet based on a vinyl chloride resin film, a plasticizer is added to the vinyl chloride resin film in order to impart flexibility. On the other hand, when producing the pressure-sensitive adhesive sheet, a laminate of the pressure-sensitive adhesive layer and release paper on the surface of the base material is wound into a roll,
It is often unwound from the roll to form a print or a coating on the surface of the substrate.

However, a substrate made of a vinyl chloride resin film containing a plasticizer as described above is soft because of its excellent flexibility. Therefore, when the surface of the substrate made of the vinyl chloride resin film opposite to the side on which the pressure-sensitive adhesive layer is formed is in strong contact with the back surface of the release paper while being wound on the roll, the release paper The phenomenon that the back surface is transferred to the base material and the appearance properties are not uniform tends to occur. Such a phenomenon is called motoling.

That is, when the surface of the base material is to be smoothed, the surface of the base material becomes cloudy instead of being smooth due to the contact of the back surface of the release paper, or the surface of the base material is treated as a matte surface. In such a case, a phenomenon in which the back surface of the release paper comes into contact with the back surface of the release paper to be in a state close to a mirror surface is called motoling.

When the above-mentioned mottling occurs, the appearance of the resulting pressure-sensitive adhesive sheet varies, and the yield decreases. Conventionally, since the vinyl chloride resin film is thermoplastic, when the final product is obtained from the roll-shaped semi-finished product, the heat is applied to the vinyl chloride resin at a temperature higher than a temperature at which the vinyl chloride resin is softened by hot air or the like, so that the appearance of the substrate surface is The properties were restored to the original state, and the pressure-sensitive adhesive sheet as the final product was wound short and loosely.

Further, Japanese Patent Application Laid-Open No. Hei 6-212133 discloses a method in which a tape or the like is interposed at both ends during winding to prevent the back surface of the release paper from adhering to a substrate made of a vinyl chloride resin film. Proposed.

[0010]

In a method in which heat is applied at a temperature higher than a temperature at which a substrate made of a vinyl chloride resin film is softened to restore the original appearance, the step of applying heat is complicated, and a large amount of heat is required. And time is required.

In the method described in JP-A-6-212133, the step of interposing a tape or the like at both ends of the pressure-sensitive adhesive sheet during winding is complicated. In addition, when the long pressure-sensitive adhesive sheet is wound into a roll, it has been difficult to relax the contact state of the back surface of the release paper with the substrate surface over the entire length direction. That is,
It was inevitable that the above-mentioned mottling would partially occur.

On the other hand, in a decorative pressure-sensitive adhesive sheet having a coating layer formed by applying a paint to the substrate surface opposite to the surface on which the pressure-sensitive adhesive layer is formed, after forming the coating layer, When wound in a roll, the back surface of the release paper strongly contacts the surface of the coating layer, and mottling occurs. In order to suppress such deterioration of the appearance properties of the coating film layer, the paint may be completely cured.

However, complete curing of the paint requires a great deal of heat and time. In addition, when curing is incomplete, mottling easily occurs. further,
If the curing is rather insufficient, blocking also occurs between the back of the release paper and the coating layer.

Therefore, the productivity of the pressure-sensitive adhesive sheet having the coating film layer formed on the surface of the substrate has to be greatly reduced as compared with the pressure-sensitive adhesive sheet using the colored vinyl chloride resin film as the substrate.

Further, under the present circumstances, in a pressure-sensitive adhesive sheet having a coating film layer formed thereon, the coating material does not have thermoplasticity, and therefore, the above-described method for improving mottling has not been generally applied.

Further, in the conventional pressure-sensitive adhesive sheet, since the vinyl chloride resin film is used as a base material as described above, hydrogen chloride gas and dioxin are generated at the time of incineration disposal. Therefore, there was a problem that the pressure-sensitive adhesive sheet could not be processed with a simple incineration facility, and the durability of the incineration facility was further reduced. Therefore, in recent years, there has been an increasing demand for a low-environmentally-friendly pressure-sensitive adhesive sheet that can be treated with a simple incineration facility.

Therefore, various attempts have been made to constitute the base material of the pressure-sensitive adhesive sheet with a polyolefin. However, when a polyolefin-based base material is used, film formation by a T-die or an inflation method is generally used. The unit must be large.

In the case of the above-mentioned colorant-containing vinyl chloride resin film substrate, a composition containing a colorant and a vinyl chloride resin is used, and the vinyl chloride resin film substrate is easily obtained by sol casting. be able to. In this case, by changing the type of the coloring agent, it is possible to easily provide a vinyl chloride resin film substrate of various colors in a small lot.

However, when a polyolefin-based substrate is used, the production unit must be considerably large as described above. To obtain substrates of various colors, a colorant is applied to the surface of the polyolefin-based film. It is necessary to work.

However, as described above, in a pressure-sensitive adhesive sheet having a coating film layer formed on the surface of a substrate, the back surface of the release paper is strongly in contact with the coating film layer when wound into a roll, and the appearance properties due to mottling are reduced. Deterioration was inevitable.

An object of the present invention is to solve the above-mentioned disadvantages of the prior art, and to provide a pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer and release paper are laminated on one side of a substrate and a coating layer is laminated on the other side. During production, even when wound into a roll, mottling caused by contact with the coating layer on the back of the release paper can be easily and effectively suppressed, and therefore, a pressure-sensitive adhesive sheet having excellent appearance properties can be obtained. It is an object of the present invention to provide a method for producing a pressure-sensitive adhesive sheet which can be provided stably and at low cost, and which can cope with small-quantity multi-products.

Another object of the present invention is to provide a pressure-sensitive adhesive sheet that can easily provide pressure-sensitive adhesive sheets of various colors without deteriorating the appearance and that can be incinerated and discarded by a simple incineration facility after use. To provide.

[0023]

The present invention relates to a method for producing a pressure-sensitive adhesive sheet comprising a coating layer, a support substrate, a pressure-sensitive adhesive layer and a release paper laminated in this order. After applying a paint to the other surface of the base material on which the pattern paper is laminated on one side, a solvent in the paint is dried to form a coating layer, and after curing at 23 ° C. for 24 hours on the surface of the coating layer, Peeling force is 10-20
It is characterized by laminating process paper of 0 g / 50 mm.

In the method for producing a pressure-sensitive adhesive sheet according to the present invention,
Preferably, a curable paint is used as the paint, and the process paper is laminated in a state where the gel fraction of the paint after drying in a solvent is in the range of 10 to 90% by weight.

In another specific aspect of the present invention, the process paper is peeled off when the gel fraction of the paint becomes 93% by weight or more. In the present invention, a stretched polypropylene sheet is used as the process paper.

In the method for producing a pressure-sensitive adhesive sheet according to the present invention, preferably, when laminating the process paper, the process paper is laminated while the surface of the coating layer is heated to 40 ° C. or higher. In the present invention, a polyolefin-based soft resin is preferably used as the support substrate.

Hereinafter, the present invention will be described in detail. The present inventor has conducted various studies on the above-mentioned problems of the prior art, and as a result, it is possible to solve the above-mentioned problems such as mottling by laminating process paper having a surface state desired to be obtained in a product on the surface of the coating layer. The present invention has been found, and it has been found that productivity can be improved while securing the desired appearance, and the present invention has been accomplished.

The material of the support substrate used in the present invention is not particularly limited as long as it has the cutting properties, flexibility and mechanical strength required for the decorative adhesive sheet. However, in general, from the viewpoints of cost, productivity, flexibility, and the like, a soft vinyl chloride resin is used as a support base material constituting the pressure-sensitive adhesive sheet.

Further, as a material constituting the supporting base material, a polyolefin-based soft resin film is preferably used. As such a polyolefin-based soft resin film, a polyethylene film, a polypropylene film, a stretched film thereof, a laminate of such a film and a film made of another material, or the like can be used. Various pigments and fillers may be added to the film.

Preferably, a polyethylene film or a polypropylene film having flexibility similar to that of the vinyl chloride resin film and low crystallinity, or propylene and ethylene having excellent stress relaxation properties similar to the vinyl chloride resin film. Or a polyolefin-based film obtained by copolymerization at the time of polymerization.

The above-mentioned polyolefin-based soft resin film can be formed by a general film-forming method such as a T-die method or an inflation method, and by combining these manufacturing methods with a stretching step and a laminating step. You can also get.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is not particularly limited, and various general pressure-sensitive adhesives such as rubber-based and acrylic-based pressure-sensitive adhesives can be used. However, in applications where weather resistance is required, among acrylic adhesives and rubber adhesives,
Hydrogenated ones are more preferred because they do not contain double bonds.

The release paper is not particularly limited as long as it can be stably peeled off from the pressure-sensitive adhesive layer. A silicone resin or a fluorine resin is coated on a coated paper, a polyethylene laminated paper, a polyethylene terephthalate film or the like. Can be used.

The coating material constituting the coating film layer is not particularly limited as long as it can express a color required as a basic performance and has a function of adhering to the surface of the supporting substrate. A one-part type such as a urethane-based coating, a melamine-based coating, a polyester-based coating, and a fluorine-based coating that can be cured only by drying, or a curable coating containing two or more liquids can be used. In addition, any one of a one-pack type paint and a two-pack type paint can be used, such as a water-based paint and an oil-based paint.

In order to uniformly apply the paint on the supporting substrate,
It is preferable to use a solvent-based paint having excellent surface wettability. For use in applications requiring weather resistance, it is desirable to use acrylic urethane-based paints or melamine-based paints used in automotive paints and building material paints having high weather resistance. In applications requiring further weather resistance, it is desirable to use an inorganic calcined pigment, a silicone resin or a fluorine resin as a paint component.

When the supporting substrate is made of a polyolefin soft resin, the surface of the supporting substrate is subjected to corona discharge treatment, flame treatment, chlorinated polypropylene or the like in order to enhance the adhesion of the supporting substrate surface. It is preferable to perform a base treatment or the like.

In laminating the support substrate, the pressure-sensitive adhesive layer, the release paper and the coating layer, various methods can be used. As an example, there is a method in which a coating material is first applied on a support base material to form a coating layer, and then an adhesive and a release paper are laminated on the opposite surface of the support base material. Alternatively, after forming a pressure-sensitive adhesive layer on the support substrate and laminating release paper, apply a paint to the surface of the support substrate opposite to the side where the pressure-sensitive adhesive layer is formed to form a coating layer Can also be adopted.

When the pressure-sensitive adhesive layer is formed, the pressure-sensitive adhesive layer may be directly applied to the surface of the substrate. However, in the case of a supporting substrate having low heat resistance and strength such as polyethylene, release paper is used. It is preferable to use a method in which an adhesive is applied on the upper surface and a pressure-sensitive adhesive layer supported by release paper is laminated with a supporting substrate.

After applying a paint on the surface of the supporting substrate, drying and forming a coating layer, laminating process paper having a surface required for the final product on the coating layer side before winding up. Thereby, it is possible to suppress a decrease in appearance properties, which is the most important quality, and to obtain a final product.

For applications requiring weather resistance, it is desirable to use a curable paint. Curing of the paint typically requires a relatively long time and a great deal of heat. Even in the case of a thick semi-finished product, a practical production speed of 10 m / min or more cannot be secured unless a furnace length of 50 m or more is used in order to cure the coating material to a state where mottling does not occur. Also, if the drying / curing temperature is set too high to apply a larger amount of heat, the solvent in the coating foams, peeling failure occurs due to insufficient heat resistance of the release paper, curling of the product and Changes in quality, rapid curing shrinkage of the paint, etc. occur, and the product quality deteriorates.

Although it is conceivable to use a catalyst for increasing the curing speed, problems such as a decrease in the gelation time of the liquid and a decrease in weather resistance due to the remaining catalyst occur. Therefore, in order to wind up the pressure-sensitive adhesive sheet at a practical production speed so as not to deteriorate the quality, it is necessary to wind up the paint in the middle of curing. If the paint is wound up in a partially cured state, the coating layer that has not been sufficiently cured comes into contact with the backside of the release paper, resulting in poor appearance due to transfer to the backside of the release paper.

However, in the present invention, when the pressure-sensitive adhesive sheet is rolled up, it has the same surface properties as the surface condition finally required on the surface of the coating layer, and peels after curing at 23 ° C. and at least 24 hours. Power is 10-200g / 50
mm process paper is laminated. Accordingly, by laminating the process paper on the surface of the coating layer and winding the pressure-sensitive adhesive sheet, it is possible to prevent deterioration of the surface properties of the coating layer.

The above-mentioned process paper needs to have a peeling force for the coating layer in the range of 10 to 200 g / 50 mm when the pressure-sensitive adhesive sheet is finally unwound from the roll and the process paper is peeled off. If the peeling force is too low, floating occurs during the peeling of the process paper, and the floating portion becomes a bubble mark, resulting in poor appearance. On the other hand, if the peeling force is too large, the process paper may be cut at the time of peeling, or the process paper may peel off while avoiding in the vertical direction, and the appearance quality of the horizontal streak tends to deteriorate.

It is desirable that the surface of the process paper conforms to the surface properties of the surface of the coating layer required for the final product. In other words, in order to obtain a finally obtained pressure-sensitive adhesive sheet having a smooth coating layer surface, the surface of the process paper to be brought into contact with the coating layer is preferably smooth, and finally obtained. When the surface of the coating layer of the pressure-sensitive adhesive sheet has irregularities such as a mat shape, it is necessary that the surface to be brought into contact with the coating layer of the process paper has such a shape.

Further, in order to stably adhere the process paper to the surface of the coating layer so as to have the above-mentioned peeling force range, the supporting substrate supporting the coating layer preferably has a weaker stiffness. Accordingly, the thickness of the support substrate varies depending on the material constituting the support substrate, but the thickness of 100 μm or more is not preferable.

In order to secure the above-mentioned peeling force, a process paper is treated with a release agent such as silicone in the same manner as the release paper to adjust the peeling force or to coat various resins having low adhesiveness with the paint. For example, the used process paper may be used. Further, when the process paper is made of a low-polarity polyolefin-based material, it can be used without performing the above-described surface treatment, as long as it can secure the peel strength at the time of peeling.

As a material constituting the process paper, preferably, a polypropylene film, a high-density polyethylene film, or a medium-density polyethylene film can be used. In particular, a stretched stretched polypropylene film, a high-neck stretched high-density polyethylene film, or the like can be used. Is particularly preferable because it is easy to control the strength at the time of peeling within the above specific range and has excellent surface smoothness. Further, the surface of the process paper may be formed into a mat by a method such as sand blasting or the like, if necessary, by blending inorganic particles with a coating agent.

When laminating the above process paper on the coating film layer, after drying the coating film layer, the adhesive sheet having the coating film layer formed thereon and the process paper are inserted between a pair of rolls in a line, and pressed. do it. However, depending on the planar shape, the dried state, and the cured state of the coating film layer, the process paper may easily float. Therefore, it is preferable that the process paper be laminated while the surface of the coating layer is heated to 40 ° C. or higher. 4
By heating the coating layer to 0 ° C. or higher, the coating layer is softened, and the adhesion between the process paper and the coating layer is increased.

Further, in order to ensure the adhesion of the process paper to the coating film layer at the time of laminating the process paper, the flexibility of the coating film layer is required. Therefore, it is desirable to laminate the process paper in a state where the curing of the paint in the coating film layer has not sufficiently proceeded, that is, when the gel fraction is in the range of 10 to 90% by weight.

The above-mentioned gel fraction means that the dried paint is immersed in tetrahydrofuran for 24 hours, dissolved,
It refers to the weight percentage of the residual paint on the wire mesh relative to the initial paint when the paint is filtered through a 280 mesh wire mesh.

When the process paper is laminated when the gel fraction is less than 10% by weight, the adhesion between the process paper and the coating layer becomes too high, and it is difficult to peel the process paper from the final product. If it exceeds 90% by weight, it may be difficult to obtain sufficient adhesion. Preferably, the process paper is laminated with the gel fraction in the range of 20 to 70% by weight.

Further, the gel fraction of the coating layer when the process paper is peeled when the final product is obtained is determined so that the process paper can be stably peeled and mottling does not occur after the peeling. It is desirable that the content be 93% by weight or more.

In the pressure-sensitive adhesive sheet according to the present invention, as described above, the coating layer is laminated on one side of the support base material, and the pressure-sensitive adhesive layer and release paper are laminated on the opposite side. It is wound in a roll shape while being laminated on the coating layer side. Therefore, when it is used as a final product, it is unwound from the roll, the process paper is peeled off, and an adhesive sheet is supplied.

(Function) In the method for producing a pressure-sensitive adhesive sheet according to the first aspect of the present invention, a pressure-sensitive adhesive sheet in which a coating layer is laminated on one side of a support substrate and a pressure-sensitive adhesive layer and release paper are laminated on the other side. At the time of production, a pressure-sensitive adhesive layer and a release paper are laminated on a support base material, a paint is laminated on the opposite surface, and at least a part of the solvent in the paint is dried to form a paint film layer, and then the paint film is formed. The process paper having the above-mentioned specific release force range is laminated on the layer surface. Therefore, even if the pressure-sensitive adhesive sheet on which the process paper is laminated is wound into a roll, the surface of the coating layer is brought into contact with the process paper. Therefore, since the back surface of the release paper hardly comes into direct contact with the coating layer, it is possible to prevent the appearance of the coating layer surface from deteriorating due to the transfer of the pattern on the back surface of the release paper. That is, the above-described mottling caused by the transfer of the back surface of the release paper can be effectively suppressed.

In addition, since the process paper has the above-mentioned specific peeling force, the process paper can be stably and easily peeled from the coating layer, and the appearance of the coating layer after the peeling is deteriorated. Hard to occur. Therefore, it is possible to provide a pressure-sensitive adhesive sheet capable of reliably exhibiting the decorative effect of the coating layer as intended.

According to the second aspect of the present invention, the paint is a curable paint, and the gel fraction of the paint after drying with the solvent is 10 to 9%.
Since the process paper is laminated at a stage within the range of 0% by weight,
The process paper is sufficiently adhered to the coating layer, the coating layer is reliably protected, and the process paper can be easily peeled off during supply of the product without deteriorating the appearance of the coating layer.

According to the third aspect of the present invention, the process paper is peeled off when the gel fraction of the paint becomes 93% by weight or more, so that the surface of the coating film layer is sufficiently cured. Even if the paper is peeled off, mottling on the surface of the coating layer hardly occurs, and a pressure-sensitive adhesive sheet having good appearance properties can be provided.

In the invention according to the fourth aspect, a stretched polypropylene film is used as the process paper, and since the stretched polypropylene film has sufficient strength and excellent surface smoothness, the appearance of the coating layer surface is improved. Deterioration of properties is more effectively suppressed.

According to the fifth aspect of the present invention, since the surface of the coating film layer is heated to 40 ° C. or more during lamination of the process paper, the surface of the coating film layer has sufficient flexibility, and It is firmly adhered to the surface.

According to the sixth aspect of the present invention, since the supporting substrate is made of a polyolefin-based soft resin, it has sufficient strength as an adhesive sheet, and can be incinerated with a simple incineration facility after use. it can. Therefore, the burden on the environment can be reduced.

[0061]

The present invention will now be described in detail with reference to non-limiting examples.

Example 1 20 parts by weight of a rutile-type titanium oxide masterbatch (titanium oxide content: 60% by weight) as a white pigment was mixed with 100 parts by weight of low-density polyethylene (manufactured by Mitsubishi Chemical Corporation, product number: LC500). Then, a polyethylene film having a thickness of 50 μm was formed by a T-die method to obtain a supporting substrate.

A two-component cross-linkable acrylic pressure-sensitive adhesive is applied to a polyethylene-laminated release paper whose surface has been treated with a silicone resin so as to have a thickness of 30 μm after drying using a comma coater, and then dried. A layer was formed. A corona discharge treatment was performed on one surface of the above-mentioned support base material, and the above-mentioned pressure-sensitive adhesive layer supported by release paper was laminated on the corona discharge treatment surface.

Next, a corona discharge treatment is applied to the surface of the support substrate opposite to the surface on which the pressure-sensitive adhesive layer and release paper are laminated, and an acrylic urethane-based paint (trade name, manufactured by Dainippon Paint Co., Ltd.) : Planit U 700, 100 parts by weight of a curing agent (trade name: Coronate 209, manufactured by Nippon Polyurethane Co.)
4) A coating obtained by adding 6.5 parts by weight is applied by a spray gun coater so that the thickness after drying becomes 20 μm, and the coating is passed through a drying furnace having a furnace length of 30 m and a drying speed of 30 m / min and / 10 ° C.
, And the process paper was laminated under the conditions shown in Table 1 below and wound up in a roll.

As the process paper, a 50 μm-thick polyethylene terephthalate (PET) film coated with silicone was used.
The surface temperature of the coating layer of the pressure-sensitive adhesive sheet was 20 ° C. The peeling force of the process paper with respect to the coating layer of the pressure-sensitive adhesive sheet thus obtained was 2 ° C at 23 ° C based on JIS Z0237.
When the peeling force after curing for 4 hours was measured, 40 g /
It was 50 mm. Further, in producing the above-mentioned pressure-sensitive adhesive tape, a part of the pressure-sensitive adhesive sheet was taken out when it was wound into a roll, and the gel fraction of the coating film layer was measured to be 40% by weight.

The roll wound up as described above is
After being left at a temperature of 3 ° C. for 24 hours, the pressure-sensitive adhesive sheet was pulled out from the roll, the process paper was peeled off, and the peelability was evaluated. That is, the peeling property at the time of peeling the process paper, the floating of the process paper, and the occurrence of mottling were visually evaluated. The results are shown in Table 1 below. In addition, peeling property,
The meanings of the evaluation symbols for the floating and mottling of the process paper are as follows.

Peelability: The peelability when the process paper was peeled was evaluated. A: Peeling was easy and no peeling streaks were observed. …: The appearance of the coating film surface was almost good, but a peeling streak was observed in a part. ×: When the process paper is peeled, the process paper is torn,
Cracks occurred in the coating layer.

Floating process paper: Before peeling the process paper, the condition of the process paper was visually observed. A: No lifting of the process paper was observed. …: The appearance defect was slightly generated after peeling due to the lifting of the process paper. X: The process paper floated over the entire surface, and poor appearance occurred over the entire surface.

Motoring condition: The coating layer after the process paper was peeled was visually observed and evaluated. A: The surface of the coating layer showed good appearance properties. …: Slight appearance defects occurred on the surface of the coating layer. X: Poor appearance of the coating layer surface was observed over the entire surface. When the process paper was peeled, a part of the coating layer was removed, and the gel fraction was measured. The results are shown in Table 1 below.

(Example 2) As process paper, the thickness was 40 μm.
A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that the stretched polypropylene (OPP) film of Example 1 was used and the peeling force of the process paper was 45 g / 50 mm.

(Example 3) The peeling force of the process paper was set to 70 g / 5.
An adhesive sheet was obtained and evaluated in the same manner as in Example 2 except that the thickness was set to 0 mm.

(Example 4) The drying temperature of the paint was set to 60 ° C., and the peeling force of the process paper was set to 5 g / 50 mm.
A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 2 except that the gel fraction of the coating layer at the time of laminating the process paper was 5% by weight.

(Example 5) As a process paper, a stretched polypropylene film having a matte surface (40 μm thick) was used.
m, and a peeling force of 40 g / 50 mm), and a pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 1.

Example 6 A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 5, except that the laminating temperature of the process paper was changed to 60 ° C.

Example 7 As a supporting substrate, a vinyl chloride resin film containing a white pigment (having a thickness of 50 μm) was used.
An adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that m) was used.

(Comparative Example 1) An adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that no paper was laminated.

(Comparative Example 2) No process paper was used.
The drying conditions of the coating layer were set at 2 m / min and a temperature of 150 ° C., and the gel fraction of the coating layer when wound on a roll was 95%.
A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that the content was set to% by weight.

(Comparative Example 3) As the process paper, the peel force was 5 g.
A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that a gel having a thickness of / 50 mm was used and the gel fraction of the coating film layer when wound up into a roll was 95% by weight.

(Comparative Example 4) As the process paper, the peeling force was 22
A pressure-sensitive adhesive sheet was obtained and evaluated in the same manner as in Example 1 except that a pressure-sensitive adhesive sheet of 0 g / 50 mm was used.

Comparative Example 5 Except that the drying conditions of the coating layer were 2 m / min and 150 ° C., and the gel fraction of the coating layer when winding the pressure-sensitive adhesive sheet on a roll was 95% by weight. ,
An adhesive sheet was obtained and evaluated in the same manner as in Example 1.

[0081]

[Table 1]

[0082]

According to the method for producing a pressure-sensitive adhesive sheet according to the present invention, a pressure-sensitive adhesive sheet comprising a support base material having a coating layer formed on one surface and a pressure-sensitive adhesive layer and release paper laminated on the opposite surface. A paint for forming a coating film layer is applied, a solvent of the coating material is dried to form a coating film layer, and a process paper having a peeling force after curing of 10 to 200 g / 50 mm is applied to the coating film layer. Even if the process paper is wound into a roll after lamination, the pattern on the back of the release paper is not transferred to the coating layer side, so that the mottling by the transfer of the pattern on the back of the release paper is ensured. Can be suppressed. Moreover, since the peeling force of the process paper is within the above-described specific range, the process paper adheres well to the coating layer, and when providing an adhesive sheet as a final product, the process is performed from the surface of the coating layer. Paper can be stably peeled off, and it becomes possible to easily provide a pressure-sensitive adhesive sheet having good appearance properties.

Thus, according to the method for producing a pressure-sensitive adhesive sheet according to the present invention, a pressure-sensitive adhesive sheet used as a decorative marking film for indoor advertising stickers, display stickers, and the like, and having good appearance properties can be obtained. It can be easily provided.

In addition, when the supporting base material is made of a polyolefin-based soft resin, unlike the case of a vinyl chloride-based resin film, even if it is incinerated with simple equipment, it does not easily cause environmental pollution. Therefore, the burden on the environment can be reduced.

Further, even when using a support base made of the above-mentioned polyolefin-based soft resin, the coloring effect is exerted by the coating film layer. Therefore, the blending of the paint and the pigment constituting the coating film layer is adjusted. Thus, it is possible to easily provide a pressure-sensitive adhesive sheet capable of exhibiting various decorative effects, and to easily cope with a small quantity and a wide variety of decorative pressure-sensitive adhesive sheets.

Claims (6)

[Claims] 1. A method for producing a pressure-sensitive adhesive sheet comprising a coating layer, a support base material, a pressure-sensitive adhesive layer, and a release paper laminated in this order, wherein the pressure-sensitive adhesive layer and the release paper are laminated on one side. A paint is applied to the other surface of the material, a solvent in the paint is dried to form a coating layer, and a peeling force after curing at 23 ° C. for 24 hours on the surface of the coating layer is 10 to 200 g / 50 mm. A method for producing a pressure-sensitive adhesive sheet, comprising laminating process papers. 2. The process paper is laminated in a state where the paint is a curable paint and the gel fraction of the paint after drying with a solvent is 10 to 90% by weight. 3. The method for producing a pressure-sensitive adhesive sheet according to item 1. 3. The method for producing a pressure-sensitive adhesive sheet according to claim 1, wherein the process paper is peeled off when the gel fraction of the paint becomes 93% by weight or more. 4. The method for producing a pressure-sensitive adhesive sheet according to claim 1, wherein the process paper comprises a stretched polypropylene sheet. 5. The method for producing a pressure-sensitive adhesive sheet according to claim 1, wherein when laminating the process paper, the lamination is performed while heating the surface of the coating layer to 40 ° C. or higher. 6. The method for producing a pressure-sensitive adhesive sheet according to claim 1, wherein the support base is made of a polyolefin-based soft resin.