JP2007144752A - Multilayered sheet and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of a multilayered sheet which is constituted by laminating an adhesive sheet and a releasable film and characterized in that the proper adhesive strength of the adhesive sheet is held with respect to the releasable film under a room temperature immediately after the adhesive sheet is formed at a high temperature and the releasable film can be peeled from the adhesive sheet in a relatively easy manner after the adhesive sheet is allowed to stand for a long period of time at room temperature, and also to provide a multilayered sheet obtained by the manufacturing method. <P>SOLUTION: The manufacturing method of the multilayered sheet is characterized in that both sides of the adhesive sheet which is composed of a thermoplastic elastomer and/or a thermoplastic resin and heated to 100-250°C are held by a polyester resin film of which the surface coming into contact with the adhesive sheet is subjected to release treatment by a silicone compound at 100-250°C. The multilayered sheet obtained by this manufacturing is also disclosed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive adhesive sheet made of a thermoplastic elastomer and / or a thermoplastic resin, a method for producing a multilayer sheet made of a polyethylene terephthalate film, and a multilayer sheet obtained thereby.

  In general, an adhesive sheet made of a thermoplastic elastomer and / or a thermoplastic resin is processed into a sheet by an extruder at a high temperature. However, when the processed adhesive sheets are stacked as they are, the adhesive sheet adheres due to the adhesiveness of the surface. Since the adhesive sheets are bonded to each other, the surface is usually protected by sandwiching both surfaces of the adhesive sheet with various release papers or plastic release films. However, depending on the type of release paper or plastic release film, the adhesive strength with the adhesive sheet is too low and easily peels off or shifts. On the other hand, the adhesive strength with the adhesive sheet is too high. There is a problem that the release paper and the release film made of plastic cannot be peeled off when using.

  In Patent Document 1, for the purpose of facilitating release, the adhesive sheet is protected by using a release film that has been subjected to a process of applying a pear pattern on the surface of the polyethylene film. It is not preferable to apply a three-dimensional pattern to the film because it takes time and cost, and is not rational and causes a problem that the three-dimensional pattern is transferred to the adhesive sheet.

JP-A-6-122858

  The present invention has an appropriate adhesive force with a release film at room temperature immediately after forming an adhesive sheet at high temperature, and relatively easily adheres to a release film after standing at room temperature for a long time. It aims at providing the multilayer sheet obtained by the manufacturing method of the multilayer sheet by which the adhesive sheet and the release film which can peel from an adhesive sheet were laminated | stacked, and the method.

  As a result of intensive research to solve the above problems, the present inventors have used a polyester film peel-treated with a silicone compound as a release film using a thermoplastic elastomer and / or a thermoplastic resin as an adhesive sheet. It was found that the problem can be solved by sandwiching both sides of the pressure-sensitive adhesive sheet at 100 to 250 ° C., and the present invention has been completed.

That is, the present invention
1. On both sides of a pressure-sensitive adhesive sheet made of a thermoplastic elastomer and / or thermoplastic resin heated to 100 to 250 ° C., at least the surface in contact with the pressure-sensitive adhesive sheet is peeled off with a silicone compound at 100 to 250 ° C. A method for producing a multilayer sheet, characterized by being sandwiched by a polyester resin film;
2. The method for producing a multilayer sheet according to 1 above, wherein the polyester resin is polyethylene terephthalate;
3. The method for producing a multilayer sheet according to 1 or 2 above, wherein the adhesive sheet contains a composition (X) comprising an aromatic vinyl-conjugated diene block copolymer;
4). 4. The method for producing a multilayer sheet according to 3 above, wherein the composition (X) comprises 100 parts by weight of an aromatic vinyl-conjugated diene block copolymer and 1 to 150 parts by weight of a tackifier resin;
5. The method for producing a multilayer sheet according to 3 or 4, wherein the conjugated diene is isoprene;
6). The composition (X) is an aromatic vinyl-isoprene block copolymer (a) having two or more polyaromatic vinyl blocks in the molecular chain (a), 10 to 98% by weight, and an aromatic vinyl-isoprene diblock copolymer. (B) The multilayer sheet according to 3 or 4 above, comprising 0 to 88% by weight and polyisoprene (c) having a weight average molecular weight of 5,000 to 300,000 and 2 to 66% by weight. Production method;
7). It is a multilayer sheet obtained by the manufacturing method of the multilayer sheet in any one of said 1-6, Comprising: The peeling strength between the said adhesive sheet and the said film made from a polyethylene terephthalate is 0.05-5.0 N / cm A multilayer sheet characterized in that
I will provide a.

  According to the method for producing a multilayer sheet of the present invention, at a high temperature, immediately after producing a multilayer sheet by sandwiching both sides of an adhesive sheet made of a thermoplastic elastomer and / or thermoplastic resin with a release film, at room temperature. Since it has moderate adhesiveness between the adhesive sheet and the release film, and when the release film is subsequently peeled off at room temperature, the adhesive force is not so strong and can be easily peeled off. Excellent work efficiency.

  Hereafter, the manufacturing method of the multilayer sheet of this invention and the multilayer sheet obtained by it are demonstrated in detail.

  The method for producing a multilayer sheet according to the present invention includes at least the pressure-sensitive adhesive sheet on both sides of a pressure-sensitive adhesive sheet made of a thermoplastic elastomer and / or a thermoplastic resin heated to 100 to 250 ° C. at 100 to 250 ° C. The surface in contact with the film is sandwiched between films made of a polyester resin that is peel-treated with a silicone compound.

  The adhesive sheet is made of a thermoplastic elastomer and / or a thermoplastic resin. As the pressure-sensitive adhesive sheet, one having adhesiveness among the thermoplastic elastomer and / or the thermoplastic resin may be used alone, and the thermoplastic elastomer and / or the thermoplastic resin is provided with adhesiveness. Or in order to raise, you may use what added tackifying resin.

  The thermoplastic elastomer is not particularly limited, and various types can be used. For example, aromatic vinyl-conjugated diene random copolymer such as styrene-butadiene random copolymer, styrene-isoprene random copolymer; fragrance such as styrene-butadiene block copolymer, styrene-isoprene block copolymer, etc. Aromatic vinyl-olefin block copolymers such as styrene-ethylene-butene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers; cyclohexene-ethylene- Hydrides of aromatic vinyl-olefin block copolymers such as butene-cyclohexene block copolymers, cyclohexene-ethylene-propylene-cyclohexene block copolymers, or alicyclic vinyl-aliphatic vinyl block copolymers; Cyano group-containing vinyl - conjugated diene copolymer; cyano group-containing vinyl - hydrides of the conjugated diene copolymer; silicone rubber; and the like. These can be used alone or in combination of two or more.

  It does not specifically limit as said thermoplastic resin, A various thing can be used. For example, polyvinyl chloride resin; polyolefin resin such as polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-n-octene copolymer; polyethylene terephthalate, polybutylene terephthalate, polyethylene isophthalate And polyester resins such as polybutylene isophthalate; polyamide resins such as nylon-6, nylon-6,6, nylon-6,12; and fluororesins such as polytetrafluoroethylene. These can be used alone or in combination of two or more.

    Various known resins can be used as the tackifying resin. For example, petroleum resin, terpene resin, phenol resin and rosin resin can be mentioned, and among these, petroleum resin is preferable. These can be used alone or in combination of two or more.

  Examples of petroleum resins include C5 petroleum resins obtained from pentene, pentadiene, isoprene, etc .; C9 petroleum resins obtained from indene, methylindene, vinyltoluene, styrene, α-methylstyrene, β-methylstyrene, etc .; C5-C9 copolymerized petroleum resins obtained from: petroleum resins obtained from cyclopentadiene and dicyclopentadiene; and hydrides of these petroleum resins; these petroleum resins are treated with maleic anhydride, maleic acid, fumaric acid, (meth) Examples include acrylic acid ((meth) acrylic acid means acrylic acid and / or methacrylic acid), modified petroleum resin modified with phenol, and the like.

  Examples of terpene resins include α-pinene resins; β-pinene resins; aromatic-modified terpene resins obtained by copolymerization of terpenes such as α-pinene and β-pinene and aromatic vinyl such as styrene. be able to.

  As a phenol resin, the condensate of phenols and formaldehyde is mentioned. Examples of the phenols include phenol, m-cresol, 3,5-xylenol, p-alkylphenol, and resorcin. Examples of the phenol resin include resole obtained by addition reaction of these phenols and formaldehyde with an alkali catalyst, novolak obtained by condensation reaction with an acid catalyst, and the like. Examples of the phenol resin include rosin phenol resins obtained by adding phenols to rosin with an acid catalyst and performing thermal polymerization.

  Examples of rosin resins include gum rosin, wood rosin or tall oil rosin; stabilized rosin or polymerized rosin disproportionated or hydrogenated using the rosin; maleic anhydride, maleic acid, fumaric acid, (meth) acrylic acid, phenol, etc. Modified rosin modified with the above; and esterified products thereof; and the like.

  The alcohol used for esterification to obtain the esterified product is preferably a polyhydric alcohol, and examples thereof include dihydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol and neopentyl glycol; glycerin, trimethylolethane, Examples include trihydric alcohols such as methylolpropane; tetrahydric alcohols such as pentaerythritol and diglycerin; hexahydric alcohols such as dipentaerythritol. These may be used singly or in combination of two or more. it can.

  Although the softening point of the tackifying resin is not particularly limited, it can be appropriately selected from a high softening point of about 200 ° C. to a liquid at room temperature depending on various uses.

  The pressure-sensitive adhesive sheet preferably contains a composition (X) made of an aromatic vinyl-conjugated diene block copolymer.

  The aromatic vinyl is not particularly limited. For example, styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, ethylstyrene, pt-butylstyrene, 2,4- Examples thereof include dimethylstyrene, and these can be used alone or in combination of two or more. Among these, styrene is preferable.

  The conjugated diene is not particularly limited, and examples thereof include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene and the like. Two or more types can be used in combination. Among these, butadiene and isoprene are preferable, and isoprene is more preferable.

  More preferably, the composition (X) comprises 100 parts by weight of an aromatic vinyl-conjugated diene block copolymer and 1 to 150 parts by weight of the tackifier resin.

  The composition (X) comprises 10 to 98% by weight of an aromatic vinyl-isoprene block copolymer (a) having two or more polyaromatic vinyl blocks in the molecular chain, and an aromatic vinyl-isoprene block copolymer. More preferably, the polymer (b) consists of 0 to 88% by weight, and the polyisoprene (c) of 2 to 66% by weight having a weight average molecular weight of 5,000 to 300,000. It is more preferable that 1 to 150 parts by weight of the tackifying resin is used in combination with respect to 100 parts by weight of the total of (c).

  The weight average molecular weight of the polyisoprene (c) is more preferably 10,000 to 200,000, particularly preferably 30,000 to 100,000.

  The content of the components (a), (b) and (c) in the composition (X) is more preferably “(a) 20 to 94% by weight, (b) 1 to 75% by weight, and (c ) 5 to 55% by weight ", particularly preferably" (a) 35 to 85% by weight, (b) 5 to 55% by weight, and (c) 10 to 35% by weight ".

  It is essential that the polyester film used for the production method of the present invention sandwiching the adhesive sheet is peeled off with a silicone compound.

  The polyester as a raw material for the polyester film is not particularly limited. For example, polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene isophthalate, polypropylene isophthalate, polybutylene isophthalate, polyethylene phthalate, polypropylene phthalate, polybutylene Examples thereof include phthalate, polyethylene adipate, polypropylene adipate, polybutylene adipate, polyethylene sebacate, polypropylene sebacate, polybutylene sebacate, and the like. These can be used alone or in combination of two or more. Among these, polyethylene terephthalate, polypropylene terephthalate, and polybutylene terephthalate are preferable, and polyethylene terephthalate is more preferable.

  It does not specifically limit as a silicone compound used in order to carry out the peeling process of the said polyester film, A various thing can be used. For example, polydimethylsiloxane, polymethylethylsiloxane, polymethylpropylsiloxane, polymethylbutylsiloxane, polymethyloctylsiloxane, polymethylvinylsiloxane, polydiethylsiloxane, polyethylbutylsiloxane, polyethylvinylsiloxane, polydipropylsiloxane, poly Aliphatic polysiloxanes such as dibutylsiloxane, polydioctylsiloxane, polydivinylsiloxane; aromatic polysiloxanes such as polydiphenylsiloxane, polymethylphenylsiloxane, polyethylphenylsiloxane, polybutylphenylsiloxane, polyphenylvinylsiloxane; Fluorinated polysiloxanes such as (trifluoromethyl) siloxane and polydi (pentafluorophenyl) siloxane Down; and the like. These may be used alone or in combination of two or more. Among these, polydimethylsiloxane, polydiphenylsiloxane, polydi (trifluoromethyl) siloxane, and polydi (pentafluorophenyl) siloxane are preferably used, and polydimethylsiloxane is more preferably used.

  By applying the silicone compound on the polyester film, the polyester film is peeled off. The method of applying the silicone compound is not particularly limited, and examples thereof include a method of dissolving the silicone compound in various solvents, coating and drying, and a method of applying a heat-melted silicone compound. Can do. If the polyester film is not peeled or if it is peeled with a substance other than a silicone compound, the polyester film as a release film is less likely to peel from the adhesive sheet after being left at room temperature, or at a high temperature. When sandwiching an adhesive sheet with a polyester film that is a release film, the adhesive film between the two layers is weak, causing the problem that the polyester film that is a release film is peeled off or displaced from the adhesive sheet there is a possibility.

  At least the surface in contact with the adhesive sheet is peeled off by the silicone compound at 100 to 250 ° C. on both sides of the adhesive sheet made of the thermoplastic elastomer and / or the thermoplastic resin heated to 100 to 250 ° C. By sandwiching between the polyester films being processed, the method for producing a multilayer sheet of the present invention is provided.

  The pressure-sensitive adhesive sheet needs to be heated to 100 to 250 ° C. When the heating temperature is lower than the lower limit of the above range, when the adhesive sheet is sandwiched between the polyester film as the release film, the polyester film as the release film is removed from the adhesive sheet because the adhesive strength between the two layers is weak. On the other hand, if the heating temperature is higher than the upper limit of the above range, the polyester film as the adhesive sheet or the release film may cause so-called “burning”, which is practical. Not. The heating temperature of the adhesive sheet is preferably in the range of 140 to 230 ° C, more preferably 160 to 210 ° C.

  The temperature at which the pressure-sensitive adhesive sheet is sandwiched between the polyester films having at least a surface in contact with the pressure-sensitive adhesive sheet peel-treated with the silicone compound needs to be 100 to 250 ° C. When the temperature at the time of pinching is lower than the lower limit of the above range, when the pressure-sensitive adhesive sheet is pinched with a polyester film that is a release film, the polyester film that is a release film is a pressure-sensitive adhesive sheet because the adhesive strength between two layers is weak On the other hand, if the temperature at the time of pinching is higher than the upper limit of the above range, there is a possibility that so-called `` burn '' may occur in the polyester film which is an adhesive sheet or a release film, Not practical. The temperature at the time of pinching becomes like this. Preferably it is 140-230 degreeC, More preferably, it is the range of 160-210 degreeC.

  The multilayer sheet of the present invention can be obtained by the manufacturing method described above. The multilayer sheet of the present invention has an appropriate adhesive force (peel strength) between the polyester film as the release film and the adhesive sheet immediately after being produced at 100 to 250 ° C., and for a long time at room temperature. Even after storage, the adhesive strength (peel strength) is not so high, so that it is easy to peel off and excellent in handleability. The peel strength between the adhesive sheet of the multilayer sheet of the present invention and the polyester film as the release film is a value measured at room temperature (23 ° C.) immediately after production and after standing at room temperature (23 ° C.) after production. Both values measured at room temperature (23 ° C.) fall within the range of 0.05 to 5.0 N / cm.

  EXAMPLES Hereinafter, although a manufacture example, an Example, and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited to these Examples. In each example, all parts and% are based on weight unless otherwise specified.

Each evaluation method is described below.
(1) Weight average molecular weight The molecular weight was determined by gel permeation chromatography (hereinafter sometimes abbreviated as “GPC”) using tetrahydrofuran as a carrier solvent. In addition, polystyrene was used as a standard substance, and the converted value was used as a measured value.
(2) “Aromatic vinyl-isoprene block copolymer component (a) having two or more polyaromatic vinyl blocks in the molecular chain” in composition (X) and “aromatic vinyl-isoprene diblock copolymer” Weight ratio of polymer component (b) "It was determined from the area ratio of the chart in the GPC measurement.
(3) Styrene content in the composition
^It was determined by ¹ H-NMR.
(4) Peel strength (N / cm):
Polyvinyl chloride is used as the adherend, and the multi-layer sheet (release film layer) is firmly adhered to the adherend with a chloroprene-based adhesive, and then peel-off adhesion between the adhesive sheet and the release film. The force was measured according to PSTC-1 (180 ° peel adhesion test by the Adhesive Tape Committee (USA)). The measurement was made immediately after production (initial: measured at 23 ° C. immediately after production of the multilayer sheet) and after 30 days (measured at 23 ° C.). The higher the value, the harder it is to peel off.
(5) Initial workability:
Based on the measurement of the peel strength immediately after (4) of the production of (4) above, the measured value is 0.05 N / cm or more (no problem level), and less than 0.05 N / cm is x (is easily peeled off and there is a problem) ).
(6) Workability after 30 days:
Based on the measurement of peel strength after 30 days in (4) above, the measured value was evaluated as ○ (no problem level) when the measured value was 5.0 N / cm or less, and x (problem was difficult to peel off) when it exceeded 5.0 N / cm. .

[Production Example 1]
To a pressure-resistant reactor, 112 parts of cyclohexane, 0.00728 parts of N, N, N ′, N′-tetramethylethylenediamine (sometimes abbreviated as “TMEDA”) and 11.7 parts of styrene are added, and Then, 0.0267 parts of n-butyllithium as an initiator was added, and the mixture was heated to 50 ° C. and polymerized for 1 hour. The polymerization conversion rate of styrene in 1 hour after the initiation of polymerization was 100%. A part of the reaction solution was sampled, and the weight average molecular weight of the polystyrene block was measured by GPC and found to be 31,000.
Subsequently, 36.3 parts of isoprene was added at a reaction temperature of 55 ° C. over 1 hour, and the polymerization reaction was continued for 1 hour after the addition was completed. The polymerization conversion rate at the end of the polymerization reaction was 100%. A part of the reaction solution was sampled and the weight average molecular weight of the styrene-isoprene diblock copolymer (b) (1) was measured by GPC and found to be 168,000.
Next, 0.0242 parts of dimethyldichlorosilane was added as a coupling agent, and a coupling reaction was performed for 2 hours to prepare a styrene-isoprene-styrene triblock copolymer (a) (1). Thereafter, 0.04 part of methanol as a polymerization terminator was added to the reactor and mixed to prepare a styrene-isoprene block copolymer composition (X) comprising the components (a), (1) and (b), (1). (1) was obtained. A part of the reaction solution was sampled, and the content of styrene units in the composition (X) (1) was measured by ¹ H-NMR analysis and found to be 24.3%. Moreover, when the weight average molecular weight of composition (X) (1) was measured by GPC, it was 307,000, (a) (1) component in composition (X) (1), and (b) ( 1) When the weight ratio of the components was measured, it was (a) (1) :( b) (1) = 85: 15.

[Production Example 2]
Using a pressure-resistant reactor, 112 parts of cyclohexane, 0.00364 parts of TMEDA and 0.134 parts of n-butyllithium were stirred and mixed at 40 ° C., then heated to 60 ° C. and 48 parts of isoprene were added over 1 hour. The polymerization reaction was continued for an additional hour after the addition of isoprene. The polymerization conversion rate of isoprene at the end of the polymerization was 100%. Thereafter, 0.2 parts of methanol as a polymerization terminator was added to the reactor and mixed to obtain polyisoprene (c) (1). It was 40,000 when the weight average molecular weight of polyisoprene (c) (1) was measured by GPC.

To 100 parts of a 30% cyclohexane solution of the styrene-isoprene block copolymer (X) (1) produced in Production Example 1, 45 parts of a 30% cyclohexane solution of polyisoprene (c) (1) produced in Production Example 2 were added. In addition, 0.3 parts of 2,6-di-tert-butyl-p-cresol, which is an antioxidant, was added and mixed, and the mixed solution was added dropwise to warm water heated to 90 ° C. with a solvent. Some cyclohexane was volatilized and removed. The obtained precipitate was filtered, pulverized, and dried with hot air at 85 ° C. to obtain a composition (X) (2).
Said composition (X) (2) was supplied to the single screw extruder provided with the underwater hot cut apparatus in the front-end | tip part of the extruder, and the round pellet (x2) of diameter 5mm was obtained.
100 parts of round pellets (x2) and 1.0 part of an antioxidant (manufactured by Ciba Specialty Chemicals Co., Ltd .: “Irganox 1010”) were added, and a T die extruder (T die: die width 250 mm, lip 1) Extruder: Extruder: 30 mmφ diameter, L / D = 38, full flight screw) was used to extrude at 200 ° C. to produce an adhesive sheet (1) having a thickness of 1 mm. Both sides of this adhesive sheet (1) are sandwiched between polyethylene terephthalate films (Toyocloth Co., Ltd .: “SP2002”, thickness: 50 μm: abbreviated as “PET-A”) that has been peeled off with a silicone compound. The laminate was pressed using a press at 180 ° C. and then cooled to room temperature (23 ° C.) to produce a multilayer sheet (1).
With respect to this multilayer sheet (1), the peel strength and workability between the adhesive sheet (1) and PET-A were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

An adhesive sheet (2) having a thickness of 1 mm was produced in the same manner as in Example 1 except that the temperature of the T-die extruder was set to 150 ° C. Both sides of this adhesive sheet (2) are sandwiched between “PET-A”, which is a polyethylene terephthalate film peel-treated with a silicone compound, and are pressure-bonded using a press at 150 ° C., and then room temperature (23 ° C.). The multilayer sheet (2) was produced.
With respect to this multilayer sheet (2), the peel strength and workability between the adhesive sheet (2) and PET-A were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

[Comparative Example 1]
The same operation as in Example 1 was performed to produce an adhesive sheet (C1) having a thickness of 1 mm. Both sides of this adhesive sheet (C1) are sandwiched between “PET-A”, which is a polyethylene terephthalate film that has been peeled off with a silicone compound, and pressed using a press at 30 ° C., and then room temperature (23 ° C.). Was cooled to a multilayer sheet (C1).
With respect to this multilayer sheet (C1), the peel strength and workability between the adhesive sheet (C1) and PET-A were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

The same operation as in Example 1 was performed to produce an adhesive sheet (3) having a thickness of 1 mm. Both sides of this adhesive sheet (3) are sandwiched between “PET-A”, which is a polyethylene terephthalate film peel-treated with a silicone compound, and are pressure-bonded using a polishing roll at 180 ° C., and then room temperature (23 ° C. ) To prepare a multilayer sheet (3).
With respect to this multilayer sheet (3), the peel strength and workability between the adhesive sheet (3) and PET-A were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

The same operation as in Example 1 was performed to produce an adhesive sheet (4) having a thickness of 1 mm. Both sides of this adhesive sheet (4) are sandwiched between “PET-A”, which is a polyethylene terephthalate film that has been peeled off with a silicone compound, and bonded with a polishing roll at 150 ° C., and then room temperature (23 ° C. ) To prepare a multilayer sheet (4).
With respect to this multilayer sheet (4), the peel strength and workability between the pressure-sensitive adhesive sheet (4) and PET-A were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

The same operation as in Example 1 was performed to produce an adhesive sheet (5) having a thickness of 1 mm. Polyethylene terephthalate film that has been peel-treated with a silicone compound on both sides of this adhesive sheet (5) (Morimura Corporation: “HPG-2”, thickness: 50 μm: abbreviated as “PET-B”) And was pressed using a press at 180 ° C., and then cooled to room temperature (23 ° C.) to produce a multilayer sheet (5).
With respect to the multilayer sheet (5), the peel strength and workability between the adhesive sheet (5) and PET-B were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

[Comparative Example 2]
The same operation as in Example 1 was performed to produce an adhesive sheet (C2) having a thickness of 1 mm. Both sides of this adhesive sheet (C2) are sandwiched between unpeeled polyethylene terephthalate films (manufactured by Teijin DuPont Co., Ltd .: “G2”, thickness 50 μm: abbreviated as “PET-C”), 30 ° C. Under pressure using a press, it was then cooled to room temperature (23 ° C.) to produce a multilayer sheet (C2).
With respect to this multilayer sheet (C2), the peel strength and workability between the adhesive sheet (C2) and PET-C were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

[Comparative Example 3]
The same operation as in Example 1 was performed to produce an adhesive sheet (C3) having a thickness of 1 mm. The both sides of this adhesive sheet (C3) are sandwiched between “PET-C”, which is a polyethylene terephthalate film that has not been peeled off, and bonded with a polishing roll at 180 ° C., and then cooled to room temperature (23 ° C.). Thus, a multilayer sheet (C3) was produced.
With respect to this multilayer sheet (C3), the peel strength and workability between the pressure-sensitive adhesive sheet (C3) and PET-C were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

[Comparative Example 4]
The same operation as in Example 1 was performed to produce an adhesive sheet (C4) having a thickness of 1 mm. Polyethylene terephthalate film (Honshu Denshi Co., Ltd .: “25R L-07 (L)”, thickness 50 μm: “PET-D”, on which both sides of this adhesive sheet (C4) are peeled with an alkyd resin And a pressure bonding using a polishing roll at 180 ° C., and then cooled to room temperature (23 ° C.) to produce a multilayer sheet (C4).
With respect to this multilayer sheet (C4), the peel strength and workability between the adhesive sheet (C4) and PET-D were evaluated immediately after production and after standing at room temperature for 30 days, respectively. The results are shown in Table 1.

From the results in Table 1, in Comparative Example 1 where the temperature when the adhesive sheet was sandwiched between the release films was low, the peel strength immediately after production (initial) was too low and the initial workability was poor. Moreover, in Comparative Example 2 and Comparative Example 3 using a polyester film that was not subjected to a release treatment for the release film, the peel strength after standing for 30 days was too high (in Comparative Example 3, the peel strength was too high and measured). (Sometimes the adhesive sheet broke) and the workability after 30 days was poor. Further, in Comparative Example 4 in which the release film is made of a polyester film that has been subjected to a release treatment with a substance that is not a silicone compound (alkyd resin), the peel strength immediately after production (initial) is too low and the initial workability is poor. It was.
On the other hand, in Examples 1 to 5 according to the present invention, the peel strength was within an appropriate range both immediately after manufacture (initial stage) and after 30 days, and excellent in workability.

Claims (7)

On both sides of a pressure-sensitive adhesive sheet made of a thermoplastic elastomer and / or thermoplastic resin heated to 100 to 250 ° C., at least the surface in contact with the pressure-sensitive adhesive sheet is peeled off with a silicone compound at 100 to 250 ° C. A method for producing a multilayer sheet, characterized in that the multilayer sheet is sandwiched by a polyester resin film. The method for producing a multilayer sheet according to claim 1, wherein the polyester resin is polyethylene terephthalate. The said adhesive sheet contains the composition (X) which consists of an aromatic vinyl-conjugated diene block copolymer, The manufacturing method of the multilayer sheet of Claim 1 or 2 characterized by the above-mentioned. The method for producing a multilayer sheet according to claim 3, wherein the composition (X) comprises 100 parts by weight of an aromatic vinyl-conjugated diene block copolymer and 1 to 150 parts by weight of a tackifier resin. The method for producing a multilayer sheet according to claim 3 or 4, wherein the conjugated diene is isoprene. The composition (X) is an aromatic vinyl-isoprene block copolymer (a) having two or more polyaromatic vinyl blocks in the molecular chain (a), 10 to 98% by weight, and an aromatic vinyl-isoprene diblock copolymer. The multilayer sheet according to claim 3 or 4, comprising (b) 0 to 88% by weight, and polyisoprene (c) having a weight average molecular weight of 5,000 to 300,000 and 2 to 66% by weight. Manufacturing method. It is a multilayer sheet obtained by the manufacturing method of the multilayer sheet in any one of Claims 1-6, Comprising: The peeling strength between the said adhesive sheet and the said polyethylene terephthalate film is 0.05-5.0N / A multilayer sheet characterized by being cm.