JP5695364B2 - Laminated body - Google Patents

Description

  The present invention relates to a laminate including a polyester-based pressure-sensitive adhesive composition layer and suitable for an adhesive tape, an adhesive sheet, and the like.

  The polyester-based pressure-sensitive adhesive has advantages such as low odor and biodegradability compared to the acrylic-based pressure-sensitive adhesive. However, since the polyester used in the polyester-based pressure-sensitive adhesive composition has functional groups capable of reacting with the crosslinking agent at both ends of the molecule, if a high molecular weight one is used, the distance between the crosslinking points becomes long. There was a possibility that heat-resistant retention might fall. In addition, when a low molecular weight material is used in order to avoid a decrease in heat resistance, the adhesive strength may be reduced due to a decrease in the distance between the crosslinking points.

  In order to improve heat resistance and the like, Patent Document 1 proposes a polyester-based pressure-sensitive adhesive composition in which two kinds of polyesters having different glass transition temperatures (Tg) are blended.

JP-A-6-145633

  However, the polyester-based pressure-sensitive adhesive composition of Patent Document 1 is still insufficient to improve the adhesive strength and heat resistance retention.

  Then, this invention provides the laminated body which can improve adhesive force and heat resistance retention property as a laminated body containing a polyester-type pressure-sensitive adhesive composition layer.

  In order to achieve the object, the laminate of the present invention includes a pressure-sensitive adhesive composition layer A and a pressure-sensitive adhesive composition layer B provided on both surfaces of the pressure-sensitive adhesive composition layer A. In the laminate, the pressure-sensitive adhesive composition layer A is formed of a polyester resin having a storage elastic modulus of 25 to 40 kPa at 200 ° C., and the pressure-sensitive adhesive composition layer B is 200 ° C. It is a laminate formed of a polyester resin having a storage elastic modulus of 10 to 20 kPa.

  According to the laminate of the present invention, it is possible to improve adhesive strength and heat resistance retention by having the above-described configuration.

  In the present invention, the pressure-sensitive adhesive composition layer A has a thickness of 10 to 200 μm and the pressure-sensitive adhesive composition layer B has a thickness of 10 to 200 μm in order to further improve the adhesive strength and heat resistance retention. It is preferable that it is 5-30 micrometers.

  In the present invention, it is preferable that the polyester resins forming the pressure-sensitive adhesive composition layers A and B are all crosslinked. This is because the cohesive force is increased by crosslinking the polyester resin, so that the adhesive force can be further improved.

  In this invention, the gel fraction of the polyester resin which forms the said pressure-sensitive adhesive composition layer A is 70 to 95 weight%, and the gel fraction of the polyester resin which forms the said pressure-sensitive adhesive composition layer B Is preferably 30 to 65% by weight. If the gel fraction is within the above range, a cohesive force suitable as a pressure-sensitive adhesive can be obtained, and the pressure-sensitive adhesive force and heat resistance retention can be improved. In this case, the cross-linking agent for cross-linking the polyester resin is preferably a trifunctional or higher polyvalent isocyanate. This is because the gel fraction of the polyester resin can be easily controlled within the preferred range.

  In this invention, it is preferable that the polyester resin which forms the said pressure sensitive adhesive composition layers A and B is manufactured from the plant-derived dicarboxylic acid and the plant-derived diol. This is because the burden on the global environment can be reduced by using plant-derived raw materials.

  In order to effectively exhibit the effects of the present invention described above, it is preferable to apply the laminate of the present invention to an adhesive tape or an adhesive sheet.

  The laminate of the present invention preferably has an adhesive strength measured according to JIS C 2107 of 10 N / 20 mm or more and a heat-resistant holding temperature for a load of 0.5 kg of 100 ° C. or more. In addition, both the said adhesive force and heat-resistant holding temperature are measured by the method as described in the Example mentioned later.

It is sectional drawing which shows an example of the laminated body of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of the laminate of the present invention. 1 includes a pressure-sensitive adhesive composition layer A (hereinafter also simply referred to as “composition layer A”) and a pressure-sensitive adhesive composition layer B (which is provided on both surfaces of the composition layer A). Hereinafter, it is simply referred to as “composition layer B”).

  The composition layer A is formed of a polyester resin having a storage elastic modulus at 200 ° C. of 25 to 40 kPa. The composition layer B is formed of a polyester resin having a storage elastic modulus at 200 ° C. of 10 to 20 kPa. In the present invention, since the composition layers A and B have a storage elastic modulus within the specific range, the adhesive force and the heat resistance retention can be improved. In addition, the value of said storage elastic modulus is a value specifically measured by the measuring method described in the Example mentioned later.

  Moreover, since the laminate of the present invention can reduce the content of acid functional groups having metal corrosive properties, it is also suitable for bonding for electronic applications, and also has low odor, so it can be used as an adhesive tape at home. It is possible.

  Furthermore, since the laminated body of this invention does not require the crosslinking process by ultraviolet irradiation, arbitrary coloring is possible. In addition, when obtaining a thick pressure-sensitive adhesive tape or pressure-sensitive adhesive sheet with a conventional acrylic pressure-sensitive pressure-sensitive adhesive, ultraviolet polymerization or the like is used, but in this case, it is thin because ultraviolet rays need to permeate the pressure-sensitive adhesive. There was a problem that only coloring was possible.

  There are various methods for adjusting the storage elastic modulus. For example, when increasing the storage elastic modulus, a high Tg monomer may be used as a raw material monomer for the polyester resin. Examples of the high Tg monomer include aliphatic monomers such as sebacic acid, propanediol, and butanediol. Moreover, what is necessary is just to reduce the compounding quantity of the crosslinking agent mentioned later, for example when reducing a storage elastic modulus.

  The storage elastic modulus at 200 ° C. of the polyester resin forming the composition layer A is preferably 27 kPa or more, and more preferably 30 kPa or more in order to further improve the heat resistance retention. Moreover, in order to improve adhesive force more, it is preferable that it is 38 kPa or less, and it is more preferable that it is 35 kPa or less. When the said viewpoint is put together, the storage elastic modulus in 200 degreeC of the polyester resin which forms the composition layer A is 25-40 kPa, It is preferable that it is 27-38 kPa, and it is more preferable that it is 30-35 kPa.

  The storage elastic modulus at 200 ° C. of the polyester resin forming the composition layer B is preferably 12 kPa or more, and more preferably 13 kPa or more in order to further improve the heat resistance retention. Moreover, in order to improve adhesive force more, it is preferable that it is 18 kPa or less, and it is more preferable that it is 17 kPa or less. When the said viewpoint is put together, the storage elastic modulus in 200 degreeC of the polyester resin which forms the composition layer B is 10-20 kPa, it is preferable that it is 12-18 kPa, and it is more preferable that it is 13-17 kPa. In the laminate shown in FIG. 1, the polyester resin forming the upper composition layer B and the polyester resin forming the lower composition layer B have a storage elastic modulus at 200 ° C. of 10 to 20 kPa. As long as they are the same polyester resin or different polyester resins.

  The thickness of the composition layer A is preferably 10 to 200 μm, and more preferably 30 to 200 μm. If the thickness of the composition layer A is 10 μm or more, the adhesive strength can be further improved. Moreover, if the thickness of the composition layer A is 200 μm or less, the heat resistance retention can be further improved.

  The thickness of the composition layer B is preferably 5 to 30 μm. If the thickness of the composition layer B is 5 μm or more, the adhesive force can be further improved. Moreover, if the thickness of the composition layer B is 30 μm or less, the heat resistance retention can be further improved.

  Further, from the viewpoint of improving the adhesive strength and heat resistance retention, the thickness of the composition layer A is preferably larger than the thickness of the composition layer B, and the thickness ratio is A: B = 4: 1 to 40: More preferably, it is within the range of 1.

  The dicarboxylic acid component for preparing the polyester resin forming the composition layers A and B is a polyvalent carboxylic acid shown below as an aliphatic dibasic acid component, or an alkyl ester or acid anhydride thereof, or a plant-derived Dimer acid can be used. For example, adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1,2-cyclohexanedicarboxylic acid, dodecenyl anhydride Examples thereof include aliphatic and alicyclic dicarboxylic acids such as acid, fumaric acid, succinic acid, dodecanedioic acid, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, maleic acid, maleic anhydride, itaconic acid, citraconic acid and the like. Of these, plant-derived dicarboxylic acids are preferable from the viewpoint of reducing environmental burden, and plant-derived dimer acid and sebacic acid are particularly preferable.

  In the present invention, an aromatic dibasic acid can also be used as the dicarboxylic acid component to the extent that the effects of the present invention are not impaired. Aromatic dibasic acids include terephthalic acid, isophthalic acid, orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 2,2'-diphenyl Examples thereof include dicarboxylic acid and 4,4′-diphenyl ether dicarboxylic acid.

  Examples of the diol component for preparing the polyester resins forming the composition layers A and B include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, and 2-methyl-1,3-propane. Diol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, Neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl-1,5-pentanediol, 2-ethyl-2-butylpropanediol, 1,9-nonanediol, 2-methyloctanediol, 1, Examples include 10-decanediol and plant-derived dimer diol. Of these, plant-derived diols are preferable from the viewpoint of reducing environmental burden, and plant-derived dimer diol and 1,4-butanediol are particularly preferable.

  The reason why dimer acid or dimer diol is preferably used for the polymer forming the pressure-sensitive adhesive is that it has a high boiling point and is difficult to evaporate during condensation polymerization, and since it has an alkyl side chain, a low Tg polymer is used. It is in the point that can be obtained.

  The polyester resin preparation method (condensation method) for forming the composition layers A and B is a method in which condensed water or monoalcohol generated by the condensation reaction is blown out of the reaction system together with an inert gas. In consideration of productivity, the reduced pressure method that can shorten the polymerization time is preferable. Although reaction temperature and a pressure reduction degree are not limited, Reaction temperature is 180-260 degreeC normally, Preferably it is 190-220 degreeC. By setting the reaction temperature to 180 ° C. or higher, a decrease in polymerization rate can be prevented. Moreover, deterioration of resin obtained can be prevented by making reaction temperature 260 degrees C or less. On the other hand, the degree of vacuum is usually 0.1 to 10 kPa, preferably 0.5 to 4 kPa. By setting the degree of vacuum to 0.1 kPa or more, the manufacturing cost can be reduced. Moreover, the fall of a polymerization rate can be prevented by making decompression degree into 10 kPa or less.

  As the catalyst used in the condensation reaction, known polyester polymerization catalysts can be used, for example, various metal compounds such as titanium, tin, antimony, zinc, and germanium, p-toluenesulfonic acid, sulfuric acid, and the like. Strong acid compounds such as can be used.

  In the present invention, the polyester resin may be crosslinked with a crosslinking agent. Although a crosslinking agent is not specifically limited, In order to easily control a gel fraction to a suitable range as an adhesive, it is preferable to use polyfunctional isocyanate more than trifunctional. As such a cross-linking agent, polyisocyanate can be used, and preferably, polyisocyanate using hexamethylene diisocyanate as a raw material can be used. Two or more of these crosslinking agents may be used in combination. In addition, although the compounding quantity of the said polyhydric isocyanate changes with kinds of isocyanate to be used, what is necessary is just to adjust suitably so that the gel fraction of the polyester resin after bridge | crosslinking may become in the suitable range mentioned later.

  The gel fraction of the polyester resin forming the composition layer A is preferably 70 to 95% by weight from the viewpoint of obtaining cohesive force suitable as a pressure-sensitive adhesive and further improving the pressure-sensitive adhesive force and heat resistance retention. It is more preferably 75 to 95% by weight, still more preferably 75 to 90% by weight, and even more preferably 80 to 90% by weight. From the same viewpoint, the gel fraction of the polyester resin forming the composition layer B is preferably 30 to 65% by weight, more preferably 35 to 60% by weight, and 40 to 60% by weight. Is more preferable, and it is still more preferable that it is 40 to 55 weight%.

  The gel fraction of the said polyester resin can be adjusted with the compounding quantity of a crosslinking agent, heating temperature, heating time, etc. In addition, the value of said gel fraction is a value specifically measured by the measuring method described in the Example mentioned later.

  In the present invention, a gelling agent may be used for the purpose of increasing the gel fraction. Examples of the gelling agent include tetra-n-butyl titanate, titanium tetraisopropoxide, butyltin oxide, dioctyltin dilaurate, and the like. Two or more of these catalysts may be used in combination.

  Although the formation method of the laminated body of this invention is not specifically limited, For example, the following method can be illustrated. First, a polyester resin-containing pressure-sensitive adhesive solution A (not shown) for forming the composition layer A and a polyester resin-containing pressure-sensitive adhesive solution B (not shown) for forming the composition layer B are prepared. Then, the sheet A (not shown) for forming the composition layer A and the sheet for forming the composition layer B are respectively applied to a support (not shown) subjected to a release treatment and dried. B (not shown). Subsequently, the laminated body of this invention can be obtained by bonding the sheet | seat B on both surfaces of the sheet | seat A, and making it age | cure | ripen suitably. In addition, as an aspect of a laminated body, an adhesive sheet, an adhesive tape, etc. are mentioned.

  According to the present invention, for example, it is possible to provide a laminate having an adhesive strength measured based on JIS C 2107 of 10 N / 20 mm or more and a heat-resistant holding temperature for a load of 0.5 kg of 100 ° C. or more. In addition, although the upper limit of the said adhesive force is not specifically limited, For example, it is 20 N / 20mm or less. The upper limit of the heat resistant holding temperature is not particularly limited, but is, for example, 200 ° C. or lower.

  Examples of the present invention will be described below together with comparative examples, but the present invention is not construed as being limited to the following examples. In the following description, “part” means “part by weight”.

<Method for producing polyester resin solution a-1>
In a reaction vessel equipped with a stirrer, a thermometer, and an outflow cooler, 35 parts of dimerdiol (manufactured by Croda Japan, Prepol 2033, weight average molecular weight: 534), 100 parts of sebacic acid (manufactured by Toyokuni Oil Co., Ltd.), 1 , 4-butanediol (Wako Pure Chemical Industries, Ltd.) 40 parts and titanium tetraisopropoxide (Wako Pure Chemical Industries, Ltd.) 0.5 parts were charged, the pressure was reduced to 0.8 kPa, and polymerization was conducted at 200 ° C. for 6 hours. Then, it was diluted with toluene so that the solid content concentration was 50% by weight to obtain a polyester resin solution a-1.

<Method for producing polyester resin solution a-2>
A polyester resin solution a-2 was obtained in the same manner as the polyester resin solution a-1, except that the amount of dimer diol was 17 parts and the amount of 1,4-butanediol was 42 parts.

<Method for producing polyester resin solution a-3>
A polyester resin solution a-3 was obtained in the same manner as the polyester resin solution a-1, except that the amount of dimer diol was 52 parts and the amount of 1,4-butanediol was 38 parts.

<Method for producing polyester resin solution a-4>
A polyester resin solution a-4 was obtained in the same manner as the polyester resin solution a-1, except that the amount of dimer diol was 8 parts and the amount of 1,4-butanediol was 45 parts.

<Method for producing polyester resin solution b>
In a reaction vessel equipped with a stirrer, a thermometer, and an outflow cooler, 100 parts of dimer diol (manufactured by Croda Japan, Prepol 2033, weight average molecular weight: 534), dimer acid (manufactured by Croda Japan, Pripol 1009, weight) Average molecular weight: 566) 99 parts and 0.5 parts of titanium tetraisopropoxide (manufactured by Wako Pure Chemical Industries, Ltd.) were charged, the pressure was reduced to 0.8 kPa, polymerization was carried out at 200 ° C. for 6 hours, and then the solid content concentration Was diluted with toluene so as to be 50% by weight to obtain a polyester resin solution b.

<Example 1>
Polyester resin solution a-1 (100 parts by weight in solids), 15 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. The pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 100 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-1. . Separately, polyester resin solution b (100 parts by weight in solid content), 1.5 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemical Co., Ltd.) which is a titanium catalyst. ) 0.1 part, and an adhesive solution was obtained. The pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 10 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet B-1. . Next, the sheet B-1 (outer layer) is laminated on both sides of the sheet A-1 (center layer) with a hand roller and laminated, and further aged in an atmosphere at 50 ° C. for 3 days to obtain the pressure-sensitive adhesive sheet of Example 1. It was.

<Example 2>
Polyester resin solution a-1 (100 parts by weight of solid content), 15 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium-based catalyst 0 1 part was mix | blended and the adhesive solution was obtained. The pressure-sensitive adhesive solution was applied to the release-treated surface of the polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 30 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-2. . Separately, polyester resin solution b (100 parts by weight in solid content), 1.5 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemical Co., Ltd.) which is a titanium catalyst. ) 0.1 part, and an adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 5 μm, and was crosslinked at 100 ° C. for 3 minutes to obtain a sheet B-2. . Next, the sheet B-2 was laminated on both surfaces of the sheet A-2 with a hand roller and laminated, and further aged for 3 days in an atmosphere at 50 ° C., to obtain an adhesive sheet of Example 2.

<Example 3>
Polyester resin solution a-1 (100 parts by weight in solids), 15 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. The pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 200 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-3. . Separately, polyester resin solution b (100 parts by weight in solid content), 1.5 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemical Co., Ltd.) which is a titanium catalyst. ) 0.1 part, and an adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 30 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet B-3. . Next, the sheet B-3 was laminated on both sides of the sheet A-3 with a hand roller and laminated, and further aged in an atmosphere at 50 ° C. for 3 days to obtain an adhesive sheet of Example 3.

<Example 4>
Polyester resin solution a-2 (100 parts by weight in solid content), 20 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to the release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 200 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-4. . Separately, polyester resin solution b (100 parts by weight in solid content), 1.2 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemical Co., Ltd.) which is a titanium catalyst. ) 0.1 part, and an adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to the release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 5 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet B-4. . Subsequently, the sheet B-4 was laminated on both surfaces of the sheet A-4 with a hand roller, and further aged in an atmosphere at 50 ° C. for 3 days to obtain an adhesive sheet of Example 4.

<Example 5>
Polyester resin solution a-3 (100 parts by weight in solids), 13 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 100 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-5. . Separately, polyester resin solution b (100 parts by weight in solid content), 2.5 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals Co., Ltd.), a polyisocyanate crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemical Co., Ltd.), a titanium catalyst. ) 0.1 part, and an adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 10 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet B-5. . Next, the sheet B-5 was laminated on both surfaces of the sheet A-5 with a hand roller and laminated, and further aged for 3 days in an atmosphere at 50 ° C. to obtain an adhesive sheet of Example 5.

<Comparative Example 1>
Polyester resin solution b (100 parts by weight in solid content), 2.5 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to the release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 100 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet B-6. . Then, using the obtained sheet B-6 as a central layer, the sheet B-1 obtained in Example 1 was laminated on both sides with a hand roller, and further aged for 3 days in an atmosphere at 50 ° C. A pressure-sensitive adhesive sheet of Comparative Example 1 was obtained.

<Comparative Example 2>
Polyester resin solution b (100 parts by weight in solids), 1.0 part of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to the release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 10 μm, and was crosslinked at 100 ° C. for 3 minutes to obtain a sheet B-7. . Next, the sheet B-7 was laminated on both surfaces of the sheet A-1 obtained in Example 1 with a hand roller, and further aged in an atmosphere at 50 ° C. for 3 days to obtain a pressure-sensitive adhesive sheet of Comparative Example 2. It was.

<Comparative Example 3>
Polyester resin solution a-3 (100 parts by weight in solids), 13 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate-based crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 10 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-6. . Next, the sheet A-6 was laminated on both surfaces of the sheet A-1 obtained in Example 1 with a hand roller, and further aged in an atmosphere at 50 ° C. for 3 days to obtain an adhesive sheet of Comparative Example 3. .

<Comparative Example 4>
The sheet B-1 obtained in Example 1 was aged in an atmosphere of 50 ° C. for 3 days as a single-layer sheet to obtain a pressure-sensitive adhesive sheet of Comparative Example 4.

<Comparative Example 5>
The sheet A-1 obtained in Example 1 was aged for 3 days in an atmosphere of 50 ° C. as a single-layer sheet to obtain a pressure-sensitive adhesive sheet of Comparative Example 5.

<Comparative Example 6>
Polyester resin solution a-4 (100 parts by weight in solid content), 15 parts of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals) which is a polyisocyanate crosslinking agent, and TC750 (manufactured by Matsumoto Fine Chemicals) which is a titanium catalyst 0 1 part was mix | blended and the adhesive solution was obtained. This pressure-sensitive adhesive solution was applied to a release-treated surface of a polyethylene terephthalate film that had been subjected to a release treatment so that the thickness after drying was 100 μm, and was crosslinked by drying at 100 ° C. for 3 minutes to obtain a sheet A-7. . Next, the sheet B-1 obtained in Example 1 was laminated on both surfaces of the sheet A-7 with a hand roller and laminated, and further aged for 3 days in an atmosphere of 50 ° C., to obtain a pressure-sensitive adhesive sheet of Comparative Example 6. .

  The following evaluation was performed about the adhesive sheet of the said sheet | seat A-1 to A-7, sheet | seat B-1 to B-7, and an Example and a comparative example. The results are shown in Table 1.

<Storage elastic modulus G '>
After drying (after crosslinking) and before lamination, the sheets A-1 to A-7 and the sheets B-1 to B-7 are cut into circular shapes with a diameter of 8 mmφ, and then peeled off from the polyethylene terephthalate film. A plurality of sheets were laminated so as to be 3 mm to prepare a measurement sample. Using a parallel plate (for shear test), this measurement sample was subjected to a frequency of 1 Hz, a measurement range of −70 to 200 ° C., and a temperature increase rate of 5 ° C./min by “Advanced Rheometric Expansion System (ARES)” manufactured by Rheometric Scientific. Measurement was performed under conditions, and the measured value at a temperature of 200 ° C. was defined as storage elastic modulus G ′.

<Gel fraction>
After drying (after crosslinking) and before lamination, the sheets A-1 to A-7 and the sheets B-1 to B-7 were cut out in a size of 5 cm × 5 cm, then peeled off from the polyethylene terephthalate film, and further 0.2 μm. After wrapping in a polytetrafluoroethylene sheet having a diameter hole (manufactured by Nitto Denko Corporation, trade name “NTF1122”), the edge of the polytetrafluoroethylene sheet is tied with a string, and the weight at that time is measured. This weight was defined as the weight before immersion. That is, the weight before immersion is the total weight of the pressure-sensitive adhesive composition layer, the polytetrafluoroethylene sheet, and the kite string. Further, the total weight of the polytetrafluoroethylene sheet and the kite string was also measured, and the weight was used as the wrapping weight. Next, the sample wrapped with the polytetrafluoroethylene sheet was immersed in toluene (50 mL) and allowed to stand at 23 ° C. for 7 days. Thereafter, the sample was taken out, transferred to an aluminum cup, dried at 130 ° C. for 2 hours to remove toluene, the weight of the sample was measured, and the weight was taken as the weight after immersion. And the gel fraction was computed from the following formula.
Gel fraction (% by weight) = (weight after immersion−wrapping bag weight) / (weight before immersion−wrapping bag weight) × 100

<Adhesive strength>
A polyethylene terephthalate film with a thickness of 25 μm subjected to corona treatment is attached to one surface of the pressure-sensitive adhesive sheet obtained in each example and comparative example, cut into a length of 110 mm and a width of 20 mm, and this is used as a measurement piece. did. This measurement piece was affixed to a stainless steel plate, and a 2 kg roller was reciprocated once on the measurement piece for pressure bonding, and then the adhesive strength was measured based on JIS C 2107 (180 degree peeling method). However, the pulling speed was 300 mm / min.

<Heat resistance retention>
An aluminum tape having a thickness of 90 μm was applied to one surface of the pressure-sensitive adhesive sheet obtained in each of the examples and comparative examples, and was cut into 10 mm × 100 mm, which was used as a measurement piece. Attach 20 mm from one end of this measurement piece to a bakelite plate (125 mm x 25 mm, thickness 2 mm), and reciprocate a 5 kg roller on the application location, and press for 30 minutes immediately after pressure bonding in an 80 ° C atmosphere. After standing, place a weight of 0.5 kg on the other tip, set the minimum measurement temperature to 60 ° C, raise the temperature at a rate of temperature increase of 1 ° C / min, and maintain the maximum temperature ( (Heat-resistant holding temperature) was investigated. The higher the heat resistant holding temperature, the better the heat resistant retaining property. In Comparative Examples 2, 3, and 5, the pasting state could not be maintained when the measurement temperature was 60 ° C.

  As shown in Table 1, the examples of the present invention showed good values for both adhesive strength and heat resistance retention. On the other hand, the comparative example was significantly inferior to the examples with respect to at least one of adhesive strength and heat resistance retention.

A pressure-sensitive adhesive composition layer (formed with a polyester resin having a storage modulus of 25 to 40 kPa at 200 ° C.)
B Pressure-sensitive adhesive composition layer (formed with a polyester resin having a storage elastic modulus at 200 ° C. of 10 to 20 kPa)

Claims (8)

A pressure-sensitive adhesive composition layer A and a laminate comprising pressure-sensitive adhesive composition layer B provided on both sides of the pressure-sensitive adhesive composition layer A,
The pressure-sensitive adhesive composition layer A is formed of a polyester resin having a storage elastic modulus at 200 ° C. of 25 to 40 kPa,
The pressure-sensitive adhesive composition layer B is formed of a polyester resin having a storage elastic modulus at 200 ° C. of 10 to 20 kPa,
The polyester resin has dicarboxylic acid components as adipic acid, azelaic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4-methyl-1 respectively. , 2-cyclohexanedicarboxylic acid, dodecenyl succinic anhydride, fumaric acid, succinic acid, dodecanedioic acid, hexahydrophthalic anhydride, tetrahydrophthalic anhydride , maleic acid, maleic anhydride, itaconic acid, citraconic acid, terephthalic acid, isophthalic acid , Orthophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, 2,2′-diphenyldicarboxylic acid, 4,4′-diphenyletherdicarboxylic acid, dimer acid Or these alkyl esters Ether or include acid anhydrides, laminate. The thickness of the pressure-sensitive adhesive composition layer A is 10 to 200 μm,
The laminate according to claim 1, wherein the pressure-sensitive adhesive composition layer B has a thickness of 5 to 30 µm.   The laminate according to claim 1 or 2, wherein the polyester resins forming the pressure-sensitive adhesive composition layers A and B are both crosslinked. The gel fraction of the polyester resin forming the pressure-sensitive adhesive composition layer A is 70 to 95% by weight,
The laminate according to claim 3, wherein a gel fraction of the polyester resin forming the pressure-sensitive adhesive composition layer B is 30 to 65% by weight.   The laminate according to claim 3 or 4, wherein the cross-linking agent for cross-linking the polyester resin is a polyfunctional isocyanate having three or more functional groups.   The laminate according to any one of claims 1 to 5, wherein the polyester resin forming the pressure-sensitive adhesive composition layers A and B is produced from a plant-derived dicarboxylic acid and a plant-derived diol.   It is an adhesive tape or an adhesive sheet, The laminated body of any one of Claims 1-6.   The laminate according to any one of claims 1 to 7, wherein the adhesive strength measured based on JIS C 2107 is 10 N / 20 mm or more, and the heat-resistant holding temperature for a load of 0.5 kg is 100 ° C or more.

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