JPH11106723A - Pressure-sensitive adhesive sheet for retarding setting of concrete surface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pressure-sensitive adhesive sheet used in a pre-tiling work to give joints finished in high accuracy and having beautiful surfaces and to facilitate the easy removal or dirt from the surfaces of tiles by laying a layer of a pressure-sensitive adhesive containing a concrete setting retarder on one surface of a synthetic resin base and laying a layer of a pressure- sensitive adhesive containing graphite on the other surface. SOLUTION: The base which can be used is any sheety product such as a film made from a synthetic resin, a woven fabric or a nonwoven fabric. The thickness of the base is desirably about 15-200 μm. The amount of the concrete setting retarder added is desirably 3-40 pts.wt. per 100 pts.wt. corresponding pressure-sensitive adhesive. The thickness of the layer of an adhesive containing a concrete setting retarder is desirably 15-80 μm. The amount of the graphite added is desirably 3-10 pts.wt. per 100 pts.wt. corresponding pressure-sensitive adhesive. It is desirable that the pressure-sensitive adhesive containing graphite is applied to part of the surface of the base, though it may be applied to the entire surface of the base. The areal coverage is desirably 20-70%. The thickness of the layer of the adhesive containing graphite is desirably 10-100 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a delayed-setting adhesive sheet for concrete surface hardening, and more particularly to a method for pre-setting a tile on a precast concrete board (PC board), which can easily remove stains on the tile surface. Or
Alternatively, the present invention relates to a concrete surface hardening delayed adhesive sheet which can be easily applied to a concrete surface to facilitate washing out of aggregate. In the present specification, a cured product of the cement composition is generically referred to as “concrete”.

[0002]

2. Description of the Related Art In buildings such as buildings, tiles are frequently used for outer walls in order to enhance aesthetic appearance. However, in order to apply tiles on site after forming a concrete wall surface, a large number of workers are required, and a long time has been required.

[0003] Therefore, a method of manufacturing a concrete panel to which tiles are previously attached in a factory and assembling it on site, that is, a pre-applied method has been adopted. In this pre-installation method, generally, a tile pack in which a required number of tiles are pasted in a matrix is manufactured, and this is set on the inner surface of a mold. Next, concrete is poured into the formwork and cured. Thereafter, after the concrete has hardened, the mold is dismantled to obtain a PC board.

However, in the pre-installation method, there is a problem that, after the concrete is cast, a part of the concrete cannot be prevented from leaking from the joint and going around the tile surface. Therefore, after the mold is disassembled after curing, the cured product of the concrete composition that has leaked to the tile surface has to be scraped off. Conventionally, the hardened concrete adhering to the tile surface has been manually scraped off with a tool such as a leather knives or a cutter knife. However, since the hardened concrete is very hard and the surface of the tile must not be damaged, this scraping operation is very complicated. Moreover, since the tile surface must not be damaged, it is difficult to mechanically remove the hardened concrete.

[0005] Therefore, there has been proposed a method of easily removing concrete stains by using a concrete setting retarder (for example, JP-A-48-29821, JP-A-61-202803).

That is, in the method disclosed in JP-A-48-29821, first, a plurality of tiles are added to a tile sheet made of paper, and a setting retarder of cement is compounded from the outer surface side of the tiles. Using an adhesive. In this method, since the outer surface side of the tile is bonded to the tile sheet surface with the setting retarder-containing adhesive, the setting speed of the concrete surface layer in contact with the portion where the adhesive is present is reduced when the concrete is hardened. . Therefore, even after the formwork is dismantled, the concrete adhering to the tile surface is not sufficiently hardened. It could be done.

[0007] However, the concrete composition contains a large amount of water. Accordingly, the paper of the tile sheet absorbs water, and the sheet tends to be wrinkled or sagged. As a result, the curing retarder did not sufficiently act on the portion where a gap was formed between the tile surface and the tile sheet, and a portion where the hard concrete hardened material was firmly attached to the tile surface had to be produced.

Further, since the tile sheet is made of paper as a base material, there is also a problem that the expansion and shrinkage due to drying during curing or moisture from cement is large, and the accuracy of the joint of the tiles is deteriorated. . Also, when the concrete surface is washed out to expose the aggregate,
The problems described above were unavoidable.

As a measure for solving the above problem, Japanese Patent Laid-Open No.
JP-A-118325 discloses a concrete surface retardation adhesive sheet in which an adhesive layer containing a concrete retarder is laminated on one surface of a substrate made of a synthetic resin.

However, recently, a method of manufacturing a concrete panel to which tiles are attached by attaching the concrete surface hardening delay adhesive sheet to an iron formwork has been carried out. A new problem arises in that the moisture in the concrete composition seeps between the adhesive sheets, causing rust on the surface of the iron formwork and impairing the surface smoothness of the iron formwork.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to form a joint with high precision in a tile pre-adhesion method, to finish the surface in a clean state, and to easily remove stains on the tile surface. A concrete surface hardening delay adhesive sheet that enables it to be removed,
An object of the present invention is to provide a concrete surface hardening delayed adhesive sheet which is suitable for use in exposing aggregate by washing out a concrete surface.

Another object of the present invention is to provide a concrete surface hardening delayed adhesive sheet which does not have a problem such as a decrease in smoothness of a mold surface due to generation of rust on the mold surface due to moisture even when manufactured using an iron mold frame or the like.

Another object of the present invention is to provide a pressure-sensitive adhesive sheet for hardening concrete surface which has good removability after being used after being attached to an iron formwork, in addition to the above-mentioned problems.

[0014]

SUMMARY OF THE INVENTION The pressure-sensitive adhesive sheet for hardening concrete surface according to the present invention has been made to achieve the above-mentioned object, and contains a concrete hardening retardant on one surface of a synthetic resin base material. An adhesive is laminated, and an adhesive containing graphite is laminated on the other surface. Further, the graphite-containing pressure-sensitive adhesive is laminated by partial coating.

The substrate used in the present invention may be any sheet-like material such as a film, woven fabric, or non-woven fabric made of a synthetic resin. The synthetic resin is not particularly limited. And polyolefin resins such as polypropylene; polyester resins such as polyethylene terephthalate and polybutylene terephthalate; soft polyvinyl chloride containing a plasticizer; fluororesin; polysulfone; and a laminate of these sheets. Further, the sheet may be stretched or unstretched. Further, in order to impart hand-cutting properties, for example, a layer obtained by laminating a polyethylene film on both sides of a polyethylene yarn cloth may be used.

When the thickness of the substrate made of the synthetic resin is thin, the strain becomes weak and it becomes difficult to use it as a tile sheet. When the thickness is large, the cost becomes high and the weight becomes heavy. Since the outer diameter of the raw material roll of the substrate roll becomes large, it is difficult to increase the length of the material and it may be difficult to use the material, it is preferably about 15 to 200 μm, more preferably 50 to 180 μm, and particularly preferably 80 to 180 μm. 140 μm.

In the present invention, a pressure-sensitive adhesive containing a concrete setting retarder is laminated on one surface of the substrate made of the above synthetic resin. As the pressure-sensitive adhesive, hitherto known pressure-sensitive adhesives can be used as long as they have compatibility with the concrete setting retarder described later.For example, rubber-based pressure-sensitive adhesives such as natural rubber and synthetic rubber, acrylic-based pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives And the like. However, when an acrylic emulsion-type pressure-sensitive adhesive is used, when the above-mentioned concrete hardening retardant is mixed into the pressure-sensitive adhesive, the adhesive strength is greatly reduced. Therefore, in the case of an acrylic emulsion type pressure-sensitive adhesive, it is preferable to use a pressure-sensitive adhesive containing 2-ethylhexyl acrylate as a main component, and in that case, it is possible to suppress a decrease in the adhesive strength.

Further, the pressure-sensitive adhesive may contain other substances as necessary within a range not to deteriorate its performance.
For example, a tackifying resin, a filler, an antioxidant and the like can be mentioned.

As the concrete setting retarder to be added to the above-mentioned pressure-sensitive adhesive, a conventionally known one can be used. For example, oxycarboxylic acids and salts thereof such as gluconic acid, tartaric acid, citric acid, malic acid, galactonic acid and salts thereof; ketocarboxylic acids such as pyruvic acid; sugar alcohols such as sorbitol and arabitol; glucose, mannose and saccharose Sugars such as sodium fluorosilicate, magnesium fluorosilicate,
Examples thereof include lead nitrate, sodium phosphate, sodium iodide, sodium humate, tannin, and linseed oil. More specifically, as the concrete hardening retardant, trade names “Joynon” (manufactured by Yamamune Chemical Co., Ltd.),
Examples of the product include a product name “Soft Coat” (manufactured by Denka Grace) and a product name “Disparite DV” (manufactured by Kyoeisha Chemical Co., Ltd.).

The amount of the concrete hardening retardant added is
When the thickness decreases, the effect of delaying the hardening of the concrete surface decreases when the thickness of the adhesive layer is small, and when it increases, the adhesive force tends to decrease, and when the thickness of the adhesive layer is large, only the concrete surface layer is used. In some cases, 3 to 40 parts by weight is preferable for 100 parts by weight of the pressure-sensitive adhesive, because the curing may be delayed to the inside. In particular, in the case of the trade name "Disparite DV", 3 to 20 parts by weight is more preferable, and in the case of the trade name "Joy Non" or the trade name "soft coat", 15 to 40 parts by weight is more preferable.

The thickness of the pressure-sensitive adhesive layer containing the concrete hardening retardant is preferably 15 to 80 μm because the effect of delaying the setting of the concrete surface is reduced when the thickness is reduced, and the adhesive tends to remain on the tile surface when the thickness is increased. Preferably, it is more preferably 20 to 70 μm, particularly preferably 2 to 70 μm.
5 to 60 μm.

An adhesive containing graphite is laminated on the other surface of the substrate made of the synthetic resin, and examples of the adhesive include those described above. The above-mentioned adhesive may contain other substances as needed as long as the performance is not reduced, and examples thereof include a tackifier resin, a filler, and an antioxidant.

By using an adhesive containing graphite, when an iron mold is used, the surface of the iron mold can be prevented from rusting due to the moisture when the concrete composition before hardening is poured. .

Examples of the graphite used in the present invention include, in addition to ordinary carbon black, scaly graphite, earthy graphite, artificial graphite, and the like. The rust on the surface of the iron mold is effectively suppressed. For this purpose, the particle size is preferably 5 to 20 μm,
It is more preferably 7 to 15 μm, particularly preferably 9 to 15 μm.
１２12 μm.

When the amount of the graphite is small, the rust-preventing effect is reduced. When the amount is large, the adhesive strength is reduced, and it is difficult to fix the graphite to the iron mold. The amount is preferably 10 parts by weight, more preferably 4 to 8 parts by weight, particularly preferably 5 to 7 parts by weight.

The above-mentioned pressure-sensitive adhesive containing graphite should be cross-linked with a cross-linking agent in order to obtain a sufficient cohesive force. Adhesive residue can be suppressed. Examples of the crosslinking agent include an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, and an aziridine-based crosslinking agent.
0.5 to 3 parts by weight per 0 parts by weight is preferred.

The graphite-containing pressure-sensitive adhesive may be laminated over the entire surface of the substrate, but is partially coated in order to obtain sufficient releasability when peeled from the iron mold after use. Is preferred. When the area ratio of the pressure-sensitive adhesive applied is small, the rust suppressing effect of graphite is not obtained, and when the ratio is large, easy peelability is not obtained. Therefore, the area ratio is preferably 20 to 70%, more preferably 35 to 60%. .

The shape of the partial coating is not particularly limited, and includes, for example, stripe coating, dot coating, wavy coating, mesh coating, and the like. Stripe coating is preferred because the coating shape can be easily changed. The partial coating can be formed into a desired shape by using a gravure coater or the like.

In the case of stripe coating, if the interval between the non-coated portions is small, the adhesive strength is high, and it is difficult to obtain sufficient removability. The interval between the engineering parts is preferably 20
１００100 mm, more preferably 30-70 mm,
Further, the interval between the coating portions is preferably 20 to 100 mm, more preferably 30 to 70 mm.

When the thickness of the above-mentioned adhesive containing graphite is small, the adhesive strength to the iron mold is low, and water oozes to the side due to the weight pressure of concrete, and rust is easily generated on the side of the mold, and the thickness is large. And rust prevention effect, but high adhesive strength,
The thickness is preferably from 10 to 100 μm, more preferably from 30 to 70 μm, particularly preferably from 40 to 60 μm, since removability is difficult to obtain.

As shown in FIG. 1, the pressure-sensitive adhesive sheet for retarding concrete surface hardening according to the present invention comprises a pressure-sensitive adhesive 2 containing a concrete curing retarder on one surface of a substrate 1 made of synthetic resin.
Is laminated, and on the other side, a graphite-containing pressure-sensitive adhesive 3 is laminated. Therefore, if necessary, a release paper (release liner) 5 may be laminated on one side as shown in FIG. Alternatively, release paper 5 may be laminated on both sides. Furthermore, if the release paper 5 has been subjected to a double-sided release treatment, it may be laminated on any one side of the concrete surface curing retardation adhesive sheet and then formed into a roll. However, usually, after the tile is first attached to the surface of the pressure-sensitive adhesive 2 containing the concrete setting retarder, the surface of the pressure-sensitive adhesive 3 containing graphite is attached to the mold inside the mold, and therefore contains graphite. Adhesive 3
It is desirable that release paper 5 be laminated on the surface. Also,
As shown in FIG. 3, the pressure-sensitive adhesive 3 containing graphite may be laminated by forming a non-applied portion 4 by partial coating.

An example of a method of applying the concrete surface-hardening delayed pressure-sensitive adhesive sheet of the present invention to the production of a precast concrete plate with pre-attached tiles will be described. First, tiles are arranged in a matrix on a pack table with the surface facing up. At this time, joints having predetermined dimensions are accurately formed, and temporary joints are embedded in the joints. Next, a concrete surface curing retardation adhesive sheet is attached so that the surface of the adhesive containing the concrete curing retardant is in contact with the tile surface to obtain a tile pack, which is set in a mold.
Thereafter, the concrete composition is poured into a mold, cured, and the concrete is cured. After the concrete is hardened, the mold is removed, and then the concrete surface hardening retardation adhesive sheet is peeled off to obtain a precast concrete plate to which tiles are pre-attached.

At this time, the cement paste is leaking from the joint portion of the tile, but the concrete surface hardly progresses hardening because the concrete hardening retardant is contained in the pressure-sensitive adhesive layer. Therefore, the cement paste or the like attached to the tile surface can be easily and reliably removed by washing with water or the like.

As an alternative, the concrete surface hardening delayed-adhesive sheet according to the present invention is set inside a mold,
A plurality of tiles may be stuck in a matrix such that the surface of the tile is in contact with the surface on which the curing retarder-containing pressure-sensitive adhesive layer is provided.

After attaching the tiles as described above,
The concrete is poured into a mold, cured, and the concrete is hardened. After the concrete is cured, the mold is removed, and then the delayed-setting adhesive sheet on the concrete surface is peeled off.

In the case of application for washing out aggregates, a concrete surface curing retardation adhesive sheet may be set on a mold so that the curing retardation adhesive layer faces inward, and then concrete may be poured.

When the concrete hardening delay function cannot be sufficiently exerted, the concrete hardening delay adhesive sheet may be affixed immediately after being peeled off from the iron mold frame. In this case, since the rust-preventing effect is sufficiently exhibited, rust does not occur on the surface and there is no need to remove the rust.

[0038]

In the pressure-sensitive adhesive sheet for hardening concrete surface according to the present invention, since the base material is made of the above-mentioned synthetic resin, wrinkles and sagging due to the influence of moisture in the concrete hardly occur. Therefore, the curing retarder can act evenly on the concrete surface, and the hardening of the cement paste leaking from the joint can be prevented. Therefore, the cement paste attached to the tile surface can be easily removed by washing with water or the like.

In addition, since the tile pack hardly expands or contracts due to drying or moisture, the joints of the tiles can be formed with high precision. In addition, since the concrete surface layer is uniformly hardened and delayed, even when the aggregate is washed out, a partial variation in the finished state of the surface hardly occurs.

[0040]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below by describing non-limiting examples of the present invention.

(Example) Adhesive containing a concrete setting retarder An acrylic emulsion type pressure-sensitive adhesive (manufactured by Sekisui Chemical Co., Ltd., trade name: Esdine # 7110) was added to 100 parts by weight of a concrete setting retarder (manufactured by Kyoeisha Chemical Co., Ltd.). (Trade name: Disparite DV) in an amount of 5 parts by weight to obtain a solution of a pressure-sensitive adhesive containing a concrete setting retarder.

Adhesive containing graphite Acrylic solvent-based adhesive (Sekisui Chemical Co., Ltd., trade name: Esdine # 7000) per 100 parts by weight of graphite (manufactured by Nishimura Graphite Co., Ltd., trade name: extra fine powder, particle size: approx. 10 μm) in the proportions (parts by weight) shown in Tables 1 and 2 below, and an isocyanate-based crosslinking agent (trade name, manufactured by Nippon Polyurethane Co., Ltd .;
By adding 0.5 part by weight of Coronate L) and mixing uniformly, a solution of a pressure-sensitive adhesive containing graphite was obtained.

(Examples 1 to 4 and Comparative Examples 1 to 3) A primer made of a 110 μm-thick polyethylene sheet obtained by laminating a 10 μm-thick polyethylene on both sides of a polyethylene yarn cloth was used. 5 g / m ^{2 of a} catalyst (trade name; Polyment NK-350), and the other surface has a surface energy of 40 to 50 dyne / c.
Corona discharge treatment was performed so as to obtain m ² to obtain a substrate.
Next, a solution of a pressure-sensitive adhesive containing a concrete setting retarder is applied on one surface of the release paper so as to have a thickness of 50 μm after drying, and dried to obtain a pressure-sensitive adhesive layer. By laminating on the surface, a semi-finished product of the above sheet was obtained. Next, a solution of the above-mentioned graphite-containing pressure-sensitive adhesive is applied on one surface of the release paper so as to have a thickness of 50 μm after drying, and dried to obtain a pressure-sensitive adhesive layer, which is laminated on the corona discharge treated surface of the substrate. As a result, a concrete surface hardening delayed adhesive sheet was obtained.

(Examples 5 to 8 and Comparative Examples 4 and 6) A base coat composed of a 110 μm thick polyethylene sheet obtained by laminating a 10 μm thick polyethylene on both sides of a polyethylene yarn cloth was coated with a primer (Japanese). 5 g / m ^{2 of a} catalyst (trade name; Polyment NK-350), and the other surface has a surface energy of 40 to 50 dyne / c.
Corona discharge treatment was performed so as to obtain m ² to obtain a substrate.
Next, a solution of a pressure-sensitive adhesive containing a concrete setting retarder is applied on one surface of the release paper so as to have a thickness of 50 μm after drying, and dried to obtain a pressure-sensitive adhesive layer. By laminating on the surface, a semi-finished product of the above sheet was obtained. Then, a solution of the above-mentioned graphite-containing pressure-sensitive adhesive was applied on one surface of the release paper in a stripe shape so as to have a thickness of 55 μm after drying, and dried to obtain a pressure-sensitive adhesive layer. Then, a concrete surface curing retardation pressure-sensitive adhesive sheet was obtained by lamination. The pressure-sensitive adhesive layer of the stripe has a coated portion width of 35 mm and a non-coated portion width of 5 mm.
It was formed using a gravure roll to have a thickness of 0 mm.

Precast concrete board with pre-tiles
Example production method was prepared as described above having 1 to 8 and Comparative Example 1
Attaching a plurality of tiles in a matrix form on the surface of the concrete surface retardation adhesive sheet of Nos. To 6 on which the adhesive containing the concrete curing retardant is laminated, and then cutting to a predetermined size Thereby, the tile pack 6 shown in FIG. 4 was produced. The tile pack 6 shown in FIG. 4 has a size of 300 mm × 600 mm, and tiles 7 each having a size of 45 mm × 95 mm are bonded in a matrix so that the width of the joint portion 8 becomes 5 mm. The joint 8 was subjected to the test without using a temporary joint material.

The tile pack obtained as described above was set with the surface of the adhesive containing graphite adhered to the bottom surface of the iron mold, 144 parts by weight of water, 320 parts by weight of cement, and 831 parts by weight of sand. , A concrete composition containing 1026 parts by weight of gravel and 3.2 parts by weight of a water reducing agent was poured into an iron mold, cured for 20 hours, and cured.

Thereafter, the mold was released, and the pressure-sensitive adhesive sheet for hardening the concrete surface was peeled off from the surface of the concrete panel to produce a precast concrete plate with a tile pre-adhesion. In this series of manufacturing processes, the following four points were measured: the accuracy of tile joint spacing, the ability to clean slag on the tile surface, the presence or absence of rust on the surface of the iron formwork, and the adhesive force of the concrete surface hardening delayed adhesive sheet. The results are shown in Tables 1 and 2 below.

[Evaluation Method] Accuracy of Tile Joint Space Tile intervals of the obtained tile precast concrete plate were arbitrarily measured at 30 places, and the average value and the maximum value of the intervals were determined.

Detergency of slag adhered to tile surface: The presence or absence of slag on the tile surface after peeling the concrete surface hardening retardation adhesive sheet from the surface of the concrete panel, and water pressure of 500 g / cm ² when there is slag
Was washed with water for 1 minute, and whether or not washing was possible was visually observed.

The presence or absence of rust on the surface of the iron formwork The surface of the iron formwork after the concrete panel was removed from the mold together with the pressure-sensitive adhesive sheet for curing the concrete surface was visually and visually observed with a touch finger.

Adhesive Strength of Concrete Surface Hardening Delayed Pressure-Sensitive Adhesive Sheet The adhesive force of the concrete surface hardening delayed-adhesive sheet to both sides of a stainless steel plate was measured according to JIS Z.
0237 “Testing method of pressure-sensitive adhesive tape / pressure-sensitive adhesive sheet” 8.3.
The measurement was performed in accordance with item 1 (180-degree peeling method).

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

According to the present invention, since the above-mentioned pressure-sensitive adhesive layer containing a curing retardant is provided on one surface of the base material, the concrete surface layer is hardened when producing a tile-attached concrete panel or washing out the aggregate on the concrete surface. Can be delayed. Moreover, since the concrete surface-hardening delayed pressure-sensitive adhesive sheet is made of a synthetic resin as a base material, it is less susceptible to the influence of moisture in the concrete composition and the drying during curing, and the base material may be bent or wrinkled. hard. Therefore, the action of the hardening retardant can be spread evenly on the concrete surface, so that the cement paste on the surface can be easily removed by washing with water or the like. It is also possible to provide a good concrete panel.

Further, since it is a double-sided pressure-sensitive adhesive sheet having a graphite-containing pressure-sensitive adhesive laminated on the other surface, the release paper can be peeled off after being made into a tile pack, and can be easily adhered to an iron mold. As a result, rust and the like are hardly generated on the surface of the iron formwork.

In particular, when the adhesive containing graphite is laminated by partial coating as in the second aspect of the present invention, the concrete surface which can be easily removed from the iron mold and which is easy to handle. A delayed-setting pressure-sensitive adhesive sheet can be provided.

[0057]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one example of a concrete surface hardening delayed pressure-sensitive adhesive sheet of the present invention.

FIG. 2 is a cross-sectional view for explaining another example of the pressure-sensitive adhesive sheet for hardening concrete surface according to the present invention.

FIG. 3 is a cross-sectional view for explaining another example of the pressure-sensitive adhesive sheet for hardening concrete surface according to the present invention.

FIG. 4 is a plan view for explaining a tile pack.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Adhesive containing a concrete hardening retarder 3 ... Adhesive containing graphite 4 ... Non-coated part of adhesive 5 ... Release paper 6 ... Tile Pack 7 ... tile 8 ... joint part

Claims (2)

[Claims] 1. A concrete characterized in that a pressure-sensitive adhesive containing a concrete setting retarder is laminated on one surface of a substrate made of a synthetic resin, and a pressure-sensitive adhesive containing graphite is laminated on the other surface. Surface hardening delayed adhesive sheet. 2. The delayed-adhesion sheet for hardening concrete surface according to claim 1, wherein the pressure-sensitive adhesive containing graphite is laminated by partial coating.