JPH04226182A - Friction treatment apparatus - Google Patents

Abstract

PURPOSE:To provide a friction treatment apparatus for producing a pressure- sensitive adhesive sheet having good rewindability and retaining good developing power for a long time and not adversely affecting the quality without using any release agent by a simple process. CONSTITUTION:A friction treatment apparatus for conducting surface treatment by giving a shearing force to the rear of the polyolefinic layer as the outermost layer of a pressure-sensitive adhesive sheet, which comprises a group of rolls including a friction roll.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an adhesive sheet (including an adhesive tape) having a polyolefin layer as the outermost layer and an adhesive layer laminated thereon, optionally via an intermediate layer, on the back side of the polyolefin layer. The present invention relates to a friction treatment device for improving the unwinding property (unrolling force) of a rolled body by applying shearing force to the surface.

0002

BACKGROUND OF THE INVENTION Adhesive sheets having an adhesive layer formed on a base material made of polyolefin are well known. The product form of these pressure-sensitive adhesive sheets is usually rolled up into a coiled body. By the way, in this rolled body, the upper adhesive layer and the back surface of the lower base material layer adhere to each other with relatively strong adhesive force, making it difficult to unwind or peel off the sheet during use. Have difficulty. Therefore, when unwinding a sheet, in order to be able to easily unwind it without causing the adhesive to migrate to the opposite side (the back side of the base material layer), blocking, or cracking of the base material layer, generally,
The back surface of the base material layer is subjected to so-called mold release treatment (peeling treatment).

[0003] Conventionally, this mold release treatment has been commonly performed by applying a release agent to the back of the base layer in advance. This contradictory behavior is difficult to control, and it is necessary to use a special release agent, apply a primer, or perform a corona treatment before applying the release agent.

[0004] As release agents, linear alkyl group-containing polymers (for example, polyvinyl ester allyl carbamate), silicone polymers, perfluoro polymers, etc. are generally used, but these release agents increase material costs. In addition, since it requires a complicated coating process, production costs increase, and even after the product is manufactured,
There is also a quality problem in that the release agent migrates to the adhesive layer, causing a decrease in adhesive strength.

[0005] Regarding surface protection films, JP-A-61-103975 proposes a method of forming and laminating a base material layer and an adhesive layer at the same time by coextrusion, which simplifies the process. It is one of the technologies that is attracting attention as an excellent technology in terms of quality, as it improves the adhesion between the adhesive and the base material layer. However, in this case as well, since the adhesive force of the adhesive layer to the base material layer is strong, it is still necessary to perform a peeling treatment on the back surface of the base material layer in order to obtain good unwinding properties. However, in the case of the coextrusion method, the problem is more serious in that it is not possible to perform a peeling treatment on the back surface of the base layer in advance, and there is a time limit on the peeling treatment.

[0006]

[Problems to be Solved by the Invention] An object of the present invention is to have good unwinding properties (unfolding force) in a simple process without using a release agent, and to maintain good unrolling force over a long period of time. Another object of the present invention is to provide a friction treatment device for producing a pressure-sensitive adhesive sheet that does not adversely affect quality.

As a result of intensive research to overcome the problems of the prior art, the present inventors found that the surface of the polyolefin layer of the adhesive sheet (the back surface of the adhesive sheet) is free from slippage due to contact with a solid substance, for example. By creating friction and applying shearing force, the fine shape and/or crystal morphology of the surface changes, and as a result, when the pressure-sensitive adhesive sheet with the surface treated surface as the back side is rolled up, It was found that the spreading force was significantly improved, and that there was no change over time in the spreading force or the initial adhesive force of the adhesive layer.

[0008] Since this surface treatment can be carried out before winding up the pressure-sensitive adhesive sheet into a roll, it can be easily carried out even on pressure-sensitive adhesive sheets produced by coextrusion. The friction treatment device for this surface treatment can be composed of a roll group including a friction roll, and an adhesive sheet is passed through the roll group to apply sliding friction to the outer surface (back surface) of the polyolefin layer of the adhesive sheet. By generating and applying shear forces, a surface treatment can be performed to improve the spreading force. The present invention has been completed based on these findings.

[0009]

[Means for Solving the Problems] According to the present invention, there is provided a friction treatment device for applying a shearing force to the back surface of the polyolefin layer of a pressure-sensitive adhesive sheet having the polyolefin layer as the outermost layer, comprising: A friction treatment device is provided, characterized in that the device consists of a roll group including a friction roll.

The present invention will be explained in detail below. In the present invention, examples of the polyolefin forming the outermost layer include polyethylene, polypropylene, copolymers such as ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and mixtures thereof. Polyolefin sheets (including tapes) may be unoriented or uniaxially or polyaxially oriented.

[0011] In the present invention, the adhesive layer is a layer having adhesive properties, and is essentially composed of an adhesive, an adhesive having adhesive properties, or a polymer having adhesive properties. As the adhesive or adhesive, rubber-based (including thermoplastic elastomer), acrylic-based, urethane-based, silicone-based adhesives, and ethylene-based adhesives, which are conventionally known as adhesives, can be used.
Vinyl acetate copolymer adhesives can be used. The composition of these adhesives is usually one in which an elastic body is appropriately blended with a tackifying resin, a softener, a filler, an anti-aging agent, and the like.

In the present invention, an intermediate layer may be provided between the polyolefin layer and the adhesive layer, and materials for the intermediate layer include kraft paper, cloth, and synthetic resin, which are conventionally used as base materials for adhesive sheets. A sheet or the like can be suitably used. Therefore, these intermediate layers constitute a base material layer together with the polyolefin layer. Note that antioxidants, ultraviolet absorbers, light stabilizers, pigments, and the like may be appropriately added to the base layer and the adhesive layer.

The thickness of each layer can be set appropriately depending on the purpose of use, but the thickness of the polyolefin layer is usually 10 to 5.
00 μm, and the thickness of the adhesive layer is usually 5 to 10 μm.
It is about 0 μm.

The timing of surface treatment to apply shearing force to the back surface of the polyolefin layer is not particularly limited, but it is necessary to perform the surface treatment before winding up the pressure-sensitive adhesive sheet into a roll. Considering productivity, etc., it is better to surface-treat the polyolefin layer alone before laminating the polyolefin layer and the adhesive layer (and optionally an intermediate layer), or after laminating the adhesive sheet than to roll up the adhesive sheet. It is desirable to surface-treat the back side of the polyolefin layer beforehand. In particular, when using a coextrusion method, it is preferable to perform surface treatment on the back surface of the polyolefin layer after forming and laminating the polyolefin layer and the adhesive layer by coextrusion.

Surface treatment that applies shearing force to the back surface of the polyolefin layer is, for example, a method of physically rubbing the surface of the polyolefin layer with a solid substance to apply shearing force parallel or perpendicular to the flow direction of the adhesive sheet. One example is a method of giving.

Since the process of manufacturing an adhesive sheet includes the process of passing through a series of rolls, in the present invention, a roll-shaped solid substance (friction roll) is used as the solid substance. The material of the friction roll is not particularly limited, but includes, for example, a metal roll with fibers or fiber moldings (e.g., gauze, cloth) wrapped around the surface, and a material between the surface layer of the metal roll and a polyolefin layer. The sliding friction coefficient is 0.3 to 0.
Examples include things that are 9. Examples of the metal include stainless steel or plated material. Further, the surface layer of the friction roll can be made of, for example, paper, rubber, or a synthetic resin film. In this case, what is important is the material of the surface layer of the friction roll, and the materials of other parts are not particularly limited.

[0017] The method of applying shear force to the back surface of the polyolefin layer using a friction roll is not particularly limited, but for example, the friction roll may be rotated in the opposite direction or in the forward direction with respect to the flow direction of the adhesive sheet, or By fixing (stopping), shearing force can be applied to the back surface of the polyolefin layer.

A specific method and apparatus for applying shearing force to the back surface of a polyolefin layer will be explained with reference to the drawings.

(1) FIG. 1 is a schematic cross-sectional view showing one embodiment of a friction treatment device for applying shearing force to the back surface of a base layer of an adhesive sheet. Reference numeral 1 in FIG. 1 is an adhesive sheet in which an adhesive layer is laminated on one side of a polyolefin layer, and the direction of the arrow (top surface) is the back surface (outer surface of the polyolefin layer).
shows. The adhesive sheet 1 created in the previous step is rolled up into a coil to form a rolled body, but before that, it is passed through a series of rolls. The adhesive sheet 1 passes through a guide roll 2 and comes into contact with fibers or a fiber molded body 6 wound around a counter-rotating roll 5 placed on a roll 4, thereby creating sliding friction between the back surface and the fibers or fiber molded body 6. and applies shearing force to the back surface. Rolls 3 and 7 are arranged before and after the counter-rotating roll to apply tension to the adhesive sheet. The surface-treated adhesive sheet is passed between pinch rolls 8 and 9 to form a roll.

[0020] The roll 5 may be rotated in the same direction as the flow direction of the pressure-sensitive adhesive sheet. When the roll 5 is rotated forward, the rotational speed (roll speed) is usually faster than the flow speed (line speed) of the adhesive tape. Further, the roll 5 may be fixed (stopped). Further, the roll surface layer may be made of metal, paper, rubber, synthetic resin film, or the like.

(2) Similar to FIG. 1, FIG. 2 shows a friction treatment in which the adhesive sheet 1 prepared in the previous step is passed through a series of rolls including friction rolls to apply shearing force to the back surface of the polyolefin layer. 3 is a schematic cross-sectional view of another embodiment of the device; FIG.

[0022] The adhesive sheet 1 is attached to pinch rolls 21 and 22.
While applying tension with left and right turn rolls 23 and 24, reverse rotation roll (or forward rotation roll) 2
5 and the back of the adhesive tape and the reverse rotating roll 25
generates sliding friction between the surface of the Then, it passes through pinch rolls 26 and 27 and is wound into a roll. The first pinch rolls 21 and 22 are not necessarily provided, but when the friction roll 25 is used as a counter-rotating roll, frictional force is applied in the opposite direction to the flow direction of the adhesive sheet, so the adhesive sheet may become sagging. Since it becomes difficult to apply the desired tension, it is usually preferable to provide one. In addition, the adhesive tape feeding speed of the pinch rolls 21 and 22 is made slightly slower than the actual adhesive sheet flow speed,
It is desirable that the adhesive tape is under tension. Alternatively, the pinch rolls 21 and 22 may be dancer rolls that apply a constant tension to the adhesive sheet.

The turn rolls 23 and 24 are movable vertically in parallel to adjust the tension applied to the adhesive sheet or the contact area between the friction roll 25 and the back surface of the base layer of the adhesive sheet. The friction roll 25 may be used as a forward rotating roll or a fixed roll. Further, the friction roll 25 may be made of metal, or a layer of fiber or fiber molding, paper, rubber, synthetic resin film, etc. may be provided on its surface.

Reference numeral 28 in FIG. 2 indicates a gas (air, etc.) outlet. If desired, by applying a gas flow of 1 to 50 kg/cm2 to the part that applies shearing force to the back surface of the polyolefin layer, in addition to the sliding frictional force caused by tension and rotational force, a sliding frictional force due to gas pressure is added. be able to.

(3) FIG. 3 shows another embodiment of the friction treatment device of the present invention. The adhesive sheet 1 created in a separate process is passed through a group of rolls including the friction roll 35. In Figure 3, reference numerals 31 and 37 are silicone rubber rolls that are driven. 32 and 38 are chrome plated rolls, which can be moved up and down by pneumatic or hydraulic pressure. Rolls 31 and 32 and rolls 37 and 38 constitute a pinch roll. 33 and 36 are silicone rubber rolls, expander rolls equipped with tension detection devices on their bearings (as they get closer to the center,
(a roll with a large roll diameter).

35 is a friction roll, for example, manufactured by Co., Ltd.
A roll made by stacking a plurality of cotton buffs manufactured by Koyo Co., Ltd., abrasive nonwoven fabric buffs, etc. to obtain the desired cotton length can be used. Furthermore, if desired, a friction roll 35
It is possible to provide an air flow blowing section 34 having a shape that surrounds the portion where the adhesive sheet 1 and the adhesive sheet 1 are in contact with each other. By blowing an air stream to this area, it is possible to prevent the adhesive tape from forming wrinkles or air bubbles during the friction treatment.

(4) FIG. 4 shows another embodiment of the friction treatment device of the present invention. The adhesive sheet 1 created in a separate process is passed through a roll group including friction rolls 44 and 46. Pinch rolls 41 and 42 and 48 and 4
9 is similar to the pinch roll in FIG. 43 and 47 are chrome plated rolls, which have the effect of smoothing out wrinkles. 44 and 46 are buff rolls (friction rolls), which can be driven in any direction of rotation or made stationary. The conveyor roll 45 is an ultra-high molecular weight polyethylene roll or a thermosetting phenol resin roll.

As shown in FIG. 4, when the buff rolls 44 and 46 are brought into contact with the conveyance roll 45 and a frictional force is applied to the back surface of the adhesive tape to apply shearing force, the shearing force is applied without applying tension. As a result, the adhesive tape does not deform. Moreover, since the conveyance roll is made of ultra-high molecular weight polyethylene or thermosetting phenol resin, wear of the roll is suppressed.

(5) FIG. 5 shows another embodiment of the friction treatment device of the present invention. This friction treatment device starts from the upstream side along the flow of the adhesive sheet with a pinch roll 51.
and 52, tension roll 53, turn roll 54, friction roll 55, turn roll 56, tension roll 5
7. Consists of a roll group consisting of pinch rolls 58 and 59. The rotation direction of the friction roll may be forward, reverse, or stationary relative to the flow direction of the adhesive sheet.

[0030] The surface layer of the friction roll is made of gauze, cloth, paper,
It is made of rubber, iron, etc., and has a coefficient of friction of 0.30 or more with the back surface of the adhesive sheet. In addition, the rotational speed (peripheral speed) of the friction roll is usually -500 m/min (a
direction) to 0 to 500 m/min (b direction). In addition, the tension roll plays a role in keeping the tension constant since the tension of the adhesive sheet changes before and after the friction roll due to shearing force caused by friction.

(6) FIG. 6 shows another embodiment of the friction treatment device of the present invention. A pinch roll 61, a friction roll 62, and a pinch roll 63 are arranged so as to be in contact with the conveyance roll 65, and the adhesive layer of the adhesive tape 1 is in contact with the conveyance roll. The friction roll 62 is made of a material that has a coefficient of friction with the back surface of the adhesive tape of 0.30 or more,
The direction of rotation may be forward, reverse, or stationary. The pinch rolls 61 and 63 are provided to prevent the adhesive sheet from being lifted off the conveyance roll 65, and do not necessarily need to be installed.

[0032]Friction rolls and pinch rolls are also
The number of installed units can be increased or decreased as desired. For example, as shown in FIG. 7, three pinch rolls 71, 73
, 76 and two friction rolls 72, 74 may be installed.

[0033] These friction treatment devices may be used singly or in combination of two or more. Furthermore, the structure of the friction roll does not necessarily have to be cylindrical; for example, when it is used in a fixed manner, it may have a semicircular cross section, without protrusions or the like on the part where the back surface of the adhesive tape contacts. Any structure that allows the adhesive sheet to slide without getting caught may be used. The shape of the friction roll is not necessarily limited to a cylindrical shape, and may be any shape as long as the surface in contact with the adhesive sheet does not have protrusions that could catch the adhesive sheet and cause it to tear.

[0034] In the present invention, the reason why a peeling effect (improving spreading force effect) is imparted to the back surface of the polyolefin layer by applying shearing force to the back surface can be estimated as follows.

[0035] Normally, the polyolefin layer is manufactured by using polyolefin as a material and extruding it using an extruder using an inflation method or a T-die method. In the process of cooling the molten resin, crystals form on the surface,
It is generally known that some parts are crystallized and others are not. The proportion of the crystallized portion can be expressed as the degree of crystallinity. It is known from a report by Komoto et al. that when shearing force is applied to the surface of polyethylene or polypropylene, the crystallographic morphology of the surface changes (We
ar, 173-182 (1982)).

By the way, when the unwinding force (unfolding force) of the roll of adhesive sheet is large, that is, for example, when the unrolling force is 10
When we observed the surface of the polyolefin layer after unwinding at 00gf/50mm (measured at an unwinding speed of 30 m/min), we found that the surface morphology changed significantly compared to immediately after cooling. It was confirmed that This change in morphology is very similar to that seen when shearing force is applied to the surface of the polyolefin layer.

[0037] One of the reasons why the rolling body has such a large unfolding force is that a force is required to change the form of the surface of the polyolefin layer during unwinding. By applying shearing force to the surface of the polyolefin layer and changing the surface morphology in advance, the force necessary for the change is no longer required, and it can be assumed that the developing force is reduced as a result.

The shearing force to be applied to the back surface of the polyolefin layer should normally be kept within a range that does not cause deformation such as neck-in of the polyolefin sheet. In the surface treatment of the polyolefin layer, the amount of work done by shearing force is 10 J or more. When it is less than 10 J, the reduction in the developing force is insufficient, and the developing force may increase due to changes in temperature and time.

[0039] When shearing force is applied to the back surface of a polyolefin layer by, for example, contacting the surface layer with a roll wrapped with nylon cloth, streaks may be formed parallel to the flow direction (longitudinal direction). be. In this case, the distance between parallel stripes is usually 5 to 20 μm, preferably 7 to 15 μm.
That's about it.

When shearing force is applied to the back surface of the adhesive sheet using a friction roll, the shearing force can be adjusted by adjusting the tension applied to the adhesive sheet. The sliding friction force due to the drag force between the friction roll and the adhesive sheet becomes a shearing force. However, in general, if too much tension is applied to the adhesive sheet, the sheet will be deformed. Therefore,
1 to 50 kg/c to the part that applies shear force to the back side of the base material layer
By applying a gas flow, generally an air flow, of m2,
In addition to the sliding frictional force caused by tension, sliding frictional force due to air pressure can be obtained, and shearing force can be obtained without deforming the adhesive sheet. Air pressure is 1
If it is less than kg/cm2, the resulting sliding friction force is too small. If it exceeds 50 kg/cm2, the tape or sheet will be deformed. Preferably 3 to 20 kg/cm2,
More preferably, it is 5 to 15 kg/cm2. Of course, as shown in FIG. 4, it is also possible to apply shearing force without applying tension. Note that the combination of the roll groups including the friction rolls is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications or combinations.
It is clear that a friction treatment can be carried out.

[0041]

[Examples] Examples of the present invention will be described in detail below, but the present invention is not limited to these examples. The physical properties were measured as follows.

<Curing after winding> After the adhesive sheet was rolled up, it was left under the three combinations of temperature and time shown in Tables 1 and 2, and the unfolding force and initial adhesive force were measured. did.

<Unfolding Force> The unfolding force from the roll is the force required when unwinding the adhesive sheet from the roll at a speed of 30 m/min, expressed as g/50 mm width conversion value.

<Initial Adhesive Strength> The adhesive sheet unwound from the rolled body is processed using a laminator according to JIS standards.
Affixed to the stainless steel plate specified in Z0237, 23
After leaving it at ℃ for 30 minutes, the force required to peel it off at an angle of 180° at a speed of 300 mm/min at 23 ℃ is g/50 mm.
Shown as width conversion value.

[Example 1] A styrene-butadiene-styrene block copolymer (trade name: ``Hyzex 3300F'', manufactured by Mitsui Petrochemical Industries, Ltd.) sheet having a thickness of 100 μm and molded by the inflation method was coated on one side of the sheet. A mixture of 100 parts by weight of ``Califlex TR1102'' manufactured by Shell Chemical Co., Ltd. and 100 parts by weight of a tackifying resin (trade name ``Clearon P100'' manufactured by Yasuyu Kogyo Co., Ltd.) was made into a homogeneous solution (solid content concentration 40%) in toluene. The resulting adhesive solution was applied and dried to a solid content thickness of 40 μm.

The obtained pressure-sensitive adhesive sheet was then coated on the surface opposite to the coated surface (back surface) using the friction treatment device shown in FIG.
A counter-rotating roll 24 wrapped with nylon cloth is used to apply a shearing force to the surface, and the pinch rolls 26 and 27
After that, it was wound onto a paper core having an inner diameter of 3 inches to form a rolled body.

The conditions for applying the shearing force are as follows: the flow speed (line speed) of the sheet is 10 m/min, the surface speed (roll speed) of the counter-rotating roll 24 is 90 m/min, and the tension applied to the sheet is 8 kg/m. there were.

[Example 2] Using the same polyethylene as in Example 1 and the same adhesive component as in Example 1 (without using toluene), both were coextruded using the T-die method to form an adhesive sheet. Other than that, Example 1
It was processed in the same manner as above to obtain a rolled body.

[Example 3] Polyethylene (trade name "Mirason 1") was coated on one side of kraft paper.
6" (manufactured by Mitsui Petrochemical Industries, Ltd.) was extruded and laminated to a thickness of 15 μm, and the surface opposite to the polyethylene surface was coated with Example 1.
An adhesive component similar to (without using a solvent) was applied by heating and melting to obtain an adhesive layer with a thickness of 40 μm. Subsequently, as shown in FIG. 2, a shearing force is applied to the back surface of the adhesive sheet using a normally rotating metal roll 24, and the adhesive sheet is passed through pinch rolls 26 and 27 to have an inner diameter of 3.
It was wound around an inch paper core to form a roll.

The conditions for applying the shearing force are that the line speed of the sheet is 10 m/min, the roll speed of the forward rotating roll 24 is 110 m/min, and the tension applied to the sheet is 20 k.
g/m, and the coefficient of sliding friction between the metal roll and the polyethylene coated surface of the sheet was 0.7.

[Comparative Example 1] A rolled body was obtained in the same manner as in Example 2 except that no shearing force was applied.

[Example 4] Polyethylene with a thickness of 60 μm molded by the inflation method (trade name "Mirason 1")
6” manufactured by Mitsui Petrochemical Industries, Ltd.) Styrene on one side of the sheet
Hydrogenated product of butadiene-styrene block copolymer (
Product name: "Krayton G1652" (manufactured by Shell Chemical Co., Ltd.) 10
0 parts by weight and tackifying resin (product name: Clearon P10
A pressure-sensitive adhesive solution made by making a homogeneous solution (solid content concentration 20% by weight) of a mixture of 20 parts by weight of 0" (manufactured by Yasushi Oil Industries Co., Ltd.) in toluene was coated and dried to a solid content thickness of 10 μm, and then As shown in FIG. 2, shearing force was applied to the back surface of the adhesive sheet using a counter-rotating roll 24 wrapped with a nylon cloth, and the adhesive sheet was passed through pinch rolls 26 and 27 and wound around a paper core having an inner diameter of 3 inches to form a roll. The conditions for applying shearing force were the same as in Example 1.

[Example 5] Example 5 except that the same polyethylene as in Example 4 and the same adhesive component as in Example 4 (no toluene was used) were used, and both were coextruded by the T-die method. A rolled body was obtained in the same manner as in 4.

[Comparative Example 2] A rolled body was obtained in the same manner as in Example 5 except that no shearing force was applied.

[Example 6] The same procedure as Example 5 was carried out until coextrusion using the T-die method. The conditions for applying shear force are that the line speed of the sheet is 10
m/min, and the roll speed of the counter-rotating roll 24 is 40 m/min.
The tension applied to the sheet was 4 kg/m2, and an air flow of 10 kg/cm2 was blown vertically from the gas outlet 28 in FIG. The measurement results of each of the above Examples and Comparative Examples are collectively shown in Table 1.

[0056]

[Table 1] *1: Sheet is stretched and deformed. *2: Unable to measure because rewinding is not possible.

[0057] In Examples 1 to 6 of the present invention, the adhesive sheet does not undergo elongation and deformation when it is peeled from the roll at a practical temperature range after being made into a roll, and the initial adhesive strength after peeling is also low. It can be seen that there is no change. In Comparative Examples 1 and 2, the unfolding force increased over time, causing the adhesive sheet to elongate and deform.
It turns out that it is practically unusable.

[Example 7] A polyethylene sheet (polyethylene; Mitsui Petrochemical Co., Ltd.) with a thickness of 60 μm was produced by inflation molding.
manufactured by Shell Chemical Co., Ltd. (trade name: Neozex 3510F), and a thermoplastic elastomer, styrene-butadiene-styrene triblock copolymer hydrogenated product (SEBS; Shell Chemical Co., Ltd.).
40 parts by weight of a tackifier resin (manufactured by Arakawa Chemical Co., Ltd., trade name Alcon P100) was added to 100 parts by weight of Kraton G1657, manufactured by Arakawa Chemical Co., Ltd., and a homogeneous solution (
A pressure-sensitive adhesive solution with a solid content concentration of 40% by weight was applied so that the solid content thickness was 10 μm, and dried to prepare a pressure-sensitive adhesive sheet. Example 1 The friction treatment apparatus shown in FIG. 1 uses a friction roll with gauze wrapped around the roll surface.
In the same manner as above, the back surface of the adhesive sheet was subjected to friction treatment, and the adhesive sheet was wound around a 3-inch paper tube to obtain a rolled body. Table 2 shows the results.

[Example 8] The same polyethylene as in Example 1 and an adhesive consisting of 100 parts by weight of SEBS and 40 parts by weight of tackifier resin (Alcon P100) were coextruded using a two-layer T-die to form a polyethylene layer of 60 μm and an adhesive layer. A 10 μm adhesive sheet was prepared. Using this adhesive sheet, friction treatment was performed in the same manner as in Example 7. The results are shown in Table 2.

[Comparative Example 3] A pressure-sensitive adhesive sheet prepared in the same manner as in Example 8 was wound up into a roll without being subjected to friction treatment. The results are shown in Table 2.

[0061]

[Table 2] *1: Sheet is stretched and deformed *3: Sheet is curled *4: Not measured because the sheet was deformed (curled)

0
062]

Effects of the Invention According to the friction treatment device of the present invention, an adhesive sheet (tape) with improved spreading force can be obtained without using a release agent, so the manufacturing process is simplified, and the steps required for release treatment are simplified. can also be easily inlined,
In addition, it has good unwinding properties even after aging and can maintain its removability over a long period of time, and there is no adverse effect on quality such as contamination of the surface of the adhered material.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing one embodiment of a friction treatment device of the present invention.

FIG. 2 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

FIG. 3 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

FIG. 4 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

FIG. 5 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

FIG. 6 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

FIG. 7 is a conceptual diagram showing one embodiment of the friction treatment device of the present invention.

[Explanation of symbols] 1 Adhesive sheet, 2 Guide roll, 5 Reverse rotation roll (friction roll), 6 Fiber or fiber molded product, 23 Turn roll, 24 Turn roll, 25 Friction roll, 28 Gas (air etc.) outlet , 34 gas (air etc.) outlet, 35 friction roll, 44 friction roll, 45 conveyance roll, 46 friction roll, 53 tension roll, 54 turn roll, 55 friction roll, 56 turn roll, 57 tension roll, 61 pinch roll , 62 friction roll, 63 pinch roll, 65 conveyance roll, 72 friction roll, 74 friction roll, 75 conveyance roll.

Claims (1)

[Claims] 1. A friction treatment device for applying a shearing force to the back surface of the polyolefin layer of a pressure-sensitive adhesive sheet having a polyolefin layer as the outermost layer for surface treatment, the device comprising a roll group including a friction roll. A friction treatment device featuring: