JP6792509B2 - Temperature sensitive adhesive - Google Patents

Description

The present invention relates to a temperature sensitive pressure-sensitive adhesive.

The temperature-sensitive pressure-sensitive adhesive contains a side-chain crystalline polymer as a main component, and when cooled to a temperature below the melting point of the side-chain crystalline polymer, the side-chain crystalline polymer crystallizes to provide adhesive strength. Is a pressure-sensitive adhesive. The temperature-sensitive adhesive is processed into a sheet, tape, etc., and is used for temporarily fixing a substrate made of glass, plastic, etc. in a manufacturing process of a flat panel display (FPD) (for example, patent documents). 1). The temperature-sensitive adhesive used for such applications may be heated to a high temperature of 200 ° C. or higher, particularly 250 ° C. or higher depending on the process, and therefore heat resistance is required. Specifically, it is required to suppress the floating of the substrate at a high temperature of 250 ° C. or higher. Further, peelability after being heated to a high temperature of 250 ° C. or higher is also required.

Japanese Unexamined Patent Publication No. 2012-102212

An object of the present invention is to provide a temperature-sensitive pressure-sensitive adhesive having excellent heat resistance and peelability after being heated to a high temperature.

As a result of diligent research to solve the above problems, the present inventors have found a solution means having the following configuration, and have completed the present invention.
(1) A temperature-sensitive pressure-sensitive adhesive containing a side-chain crystalline polymer and whose adhesive strength decreases at a temperature lower than the melting point of the side-chain crystalline polymer, wherein the side-chain crystalline polymer has 16 or more carbon atoms. A temperature-sensitive pressure-sensitive adhesive containing (meth) acrylate, methyl (meth) acrylate and dicyclopentanyl (meth) acrylate having a linear alkyl group as a monomer component, and further containing a pressure-sensitive adhesive made of a styrene resin. ..
(2) The temperature-sensitive pressure-sensitive adhesive according to (1) above, which contains the dicyclopentanyl (meth) acrylate in a monomer component in a proportion of 5 to 35% by weight.
(3) The temperature-sensitive pressure-sensitive adhesive according to (1) or (2) above, which contains the pressure-sensitive adhesive in a proportion of 20 to 50 parts by weight with respect to 100 parts by weight of the side chain crystalline polymer.
(4) The temperature sensitivity according to any one of (1) to (3) above, wherein the 180 ° peel strength with respect to the polyimide film at 5 ° C. after 1 hour at 250 ° C. is 0.15 N / 25 mm or less. Adhesive.
(5) The temperature-sensitive adhesive according to any one of (1) to (4) above, which is used for temporarily fixing a substrate in a manufacturing process of a flat panel display.
(6) A temperature-sensitive pressure-sensitive adhesive sheet containing the temperature-sensitive pressure-sensitive adhesive according to any one of (1) to (5) above.
(7) A film-like base material and a pressure-sensitive adhesive layer laminated on at least one side of the base material and containing the temperature-sensitive pressure-sensitive adhesive according to any one of (1) to (5) above. Temperature sensitive adhesive tape.

According to the present invention, there is an effect that the heat resistance and the peelability after being heated to a high temperature are excellent.

It is a graph which shows the result of thermogravimetric analysis in an Example.

<Temperature-sensitive adhesive>
Hereinafter, the temperature-sensitive pressure-sensitive adhesive according to an embodiment of the present invention will be described in detail.
The temperature sensitive pressure-sensitive adhesive of the present embodiment contains a side chain crystalline polymer. The side chain crystalline polymer is a polymer having a melting point. Melting point is the temperature at which a specific portion of a polymer initially matched to an ordered sequence becomes disordered by a certain equilibrium process and is 10 ° C./min using a differential thermal scanning calorimeter (DSC). It shall mean the value obtained by measuring under the measurement conditions.

The side chain crystalline polymer crystallizes at a temperature below the melting point described above, and undergoes a phase transition at a temperature above the melting point to exhibit fluidity. That is, the side chain crystalline polymer has a temperature sensitivity that reversibly causes a crystalline state and a flowing state in response to a temperature change.

The temperature-sensitive pressure-sensitive adhesive of the present embodiment has a reduced adhesive strength at a temperature lower than the melting point of the side chain crystalline polymer. In other words, the temperature-sensitive pressure-sensitive adhesive of the present embodiment contains the side-chain crystalline polymer at a rate at which the adhesive strength decreases when the side-chain crystalline polymer crystallizes at a temperature below the melting point. That is, the temperature-sensitive pressure-sensitive adhesive of the present embodiment contains a side chain crystalline polymer as a main component. Therefore, when peeling the adherend from the temperature-sensitive pressure-sensitive adhesive, if the temperature-sensitive pressure-sensitive adhesive is cooled to a temperature below the melting point of the side-chain crystalline polymer, the side-chain crystalline polymer crystallizes and adheres. Power is reduced. Further, if the temperature-sensitive pressure-sensitive adhesive is heated to a temperature equal to or higher than the melting point of the side-chain crystalline polymer, the side-chain crystalline polymer exhibits fluidity and the adhesive strength is restored, so that the adhesive can be used repeatedly.

The side chain crystalline polymer contains (meth) acrylate having a linear alkyl group having 16 or more carbon atoms as a monomer component. In a (meth) acrylate having a linear alkyl group having 16 or more carbon atoms, the linear alkyl group having 16 or more carbon atoms functions as a side chain crystalline site in the side chain crystalline polymer. That is, the side chain crystalline polymer is a comb-shaped polymer having a linear alkyl group having 16 or more carbon atoms in the side chain, and the side chain is crystallized by being matched to an ordered arrangement by intermolecular force or the like. To do.

Examples of the (meth) acrylate having a linear alkyl group having 16 or more carbon atoms include cetyl (meth) acrylate, stearyl (meth) acrylate, eicosyl (meth) acrylate, and behenyl (meth) acrylate, which have 16 to 16 carbon atoms. Examples thereof include (meth) acrylates having 22 linear alkyl groups. As the exemplified (meth) acrylate, only one kind may be used, or two or more kinds may be used in combination. The (meth) acrylate means acrylate or methacrylate.

The proportion of the (meth) acrylate having a linear alkyl group having 16 or more carbon atoms in the monomer component, that is, in all the monomer components constituting the side chain crystalline polymer is, for example, 10 to 55% by weight.

Here, the side chain crystalline polymer of the present embodiment contains methyl (meth) acrylate and dicyclopentanyl (meth) acrylate as monomers in addition to the (meth) acrylate having a linear alkyl group having 16 or more carbon atoms. Included as an ingredient. In other words, the side chain crystalline polymer of the present embodiment contains at least a (meth) acrylate having a linear alkyl group having 16 or more carbon atoms, a methyl (meth) acrylate, and a dicyclopentanyl (meth) acrylate. It is a copolymer of. The temperature-sensitive pressure-sensitive adhesive of the present embodiment further contains a pressure-sensitive adhesive made of a styrene resin in addition to the side-chain crystalline polymer.

According to the above-described configuration, excellent heat resistance can be exhibited, and the effect of excellent peelability after being heated to a high temperature can also be obtained. Specifically, even if the adherend such as a substrate is heated to a high temperature of 250 ° C. or higher in a fixed state, it is possible to suppress the occurrence of floating of the adherend. Further, the 180 ° peel strength with respect to the polyimide film at 5 ° C. after 1 hour at 250 ° C. obtained by the measuring method described in Examples described later is 0.15 N / 25 mm or less, preferably 0.1 N. / 25 mm or less. Therefore, the temperature-sensitive pressure-sensitive adhesive of the present embodiment can be suitably used for temporarily fixing the substrate in the manufacturing process of the FPD.

The following reasons can be presumed as the reason why the effect of excellent heat resistance and peelability after being heated to a high temperature can be obtained. Normally, when heated to a high temperature, the cohesive force decreases and the fluidity increases, so that the heat resistance tends to decrease, and the anchor effect developed when the side chain crystalline polymer crystallizes becomes stronger and peels off. The sex is also likely to decline. When the temperature-sensitive pressure-sensitive adhesive has the above-mentioned structure, thermal deterioration is less likely to occur at a high temperature of 200 ° C. or higher, particularly 250 ° C. or higher. When the heat deterioration is less likely to occur at a high temperature, the cohesive force is less likely to decrease at a high temperature, so that excellent heat resistance can be exhibited. In addition, the increase in fluidity is small even when heated to a high temperature, and the extreme anchor effect is less likely to be exhibited when the side chain crystalline polymer is crystallized. As a result, excellent peelability can be exhibited even after being heated to a high temperature.

Of the above-mentioned monomer components, methyl (meth) acrylate mainly functions as a component that imparts cohesive force to the temperature-sensitive pressure-sensitive adhesive. The proportion of methyl (meth) acrylate in the monomer component is, for example, 10 to 85% by weight. When methyl (meth) acrylate is contained in the monomer component in the largest proportion, the heat resistance tends to be improved.

Dicyclopentanyl (meth) acrylate mainly functions as a component for enhancing the heat resistance of the temperature-sensitive pressure-sensitive adhesive. The proportion of dicyclopentanyl (meth) acrylate in the monomer component is, for example, 5 to 35% by weight.

As the tackifier as described above, a commercially available product can be used. Examples of commercially available tackifiers include "YS Resin SX100" manufactured by Yasuhara Chemical Co., Ltd.

The tackifier is contained in an amount of, for example, 1 part by weight or more, preferably 20 to 100 parts by weight, and more preferably 20 to 50 parts by weight, based on 100 parts by weight of the side chain crystalline polymer.

The softening point of the tackifier is, for example, 90 to 110 ° C, preferably 95 to 105 ° C. The softening point is a value measured according to the ring-and-ball method defined in JIS K 5902.

On the other hand, the monomer component constituting the side chain crystalline polymer may contain a monomer other than the above-mentioned monomer. Examples of other monomers include polar monomers and reactive fluorine compounds.

When a polar monomer is contained as a monomer component, the adhesive physical properties of the temperature-sensitive pressure-sensitive adhesive can be adjusted. Examples of the polar monomer include ethylenically unsaturated monomers having a carboxyl group such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, and fumaric acid; 2-hydroxyethyl (meth) acrylate and 2-hydroxy. Examples thereof include ethylenically unsaturated monomers having a hydroxyl group such as propyl (meth) acrylate and 2-hydroxyhexyl (meth) acrylate. As the exemplified polar monomer, only one kind may be used, or two or more kinds may be used in combination. The proportion of polar monomer in the monomer component is, for example, 1 to 10% by weight.

When a polar monomer is further contained as a monomer component, the ratio of each monomer in the monomer component is, for example, 9 to 45% by weight of (meth) acrylate having a linear alkyl group having 16 or more carbon atoms, and methyl (meth) acrylate. Is 10 to 85% by weight, dicyclopentanyl (meth) acrylate is 5 to 35% by weight, and polar monomer is 1 to 10% by weight.

When the reactive fluorine compound is contained as a monomer component, if the temperature-sensitive pressure-sensitive adhesive is cooled to a temperature below the melting point of the side-chain crystalline polymer, in addition to the decrease in adhesive strength due to crystallization of the side-chain crystalline polymer. Since the releasability caused by the fluorine compound is also added, the adhesive strength can be greatly reduced.

The reactive fluorine compound means a fluorine compound having a functional group exhibiting reactivity. Examples of the functional group exhibiting reactivity include an epoxy group (including a glycidyl group and an epoxycycloalkyl group), a mercapto group, a carbinol group (methylol group), a carboxyl group, a silanol group, a phenol group, an amino group, a hydroxyl group, and the like. Examples thereof include a group having an ethylenically unsaturated double bond. Examples of the group having an ethylenically unsaturated double bond include a vinyl group, an allyl group, a (meth) acrylic group, a (meth) acryloyl group, and a (meth) acryloyloxy group.

Specific examples of the reactive fluorine compound include a compound represented by the following general formula (I).

［式中、Ｒ₁は基：ＣＨ₂＝ＣＨＣＯＯＲ²−またはＣＨ₂＝Ｃ（ＣＨ₃）ＣＯＯＲ²−（式中、Ｒ²はアルキレン基を示す。）を示す。］

[In the formula, R ₁ indicates a group: CH ₂ = CHCOOR ^2- or CH ₂ = C (CH ₃ ) COOR ^2- (in the formula, R ² indicates an alkylene group). ]

Examples of the alkylene group indicated by R ² include a linear or branched alkylene group having 1 to 6 carbon atoms such as a methylene group, an ethylene group, a trimethylene group, a propylene group, a tetramethylene group, a pentamethylene group and a hexamethylene group. Can be mentioned.

Specific examples of the compound represented by the general formula (I) include 2,2,2-trifluoroethyl acrylate represented by the following formula (Ia) and 2,2,2- represented by the formula (Ib). Examples thereof include trifluoroethyl methacrylate.

As the above-mentioned reactive fluorine compound, a commercially available product can be used. Examples of commercially available reactive fluorine compounds include "Viscoat 3F", "Viscoat 3FM", "Viscoat 4F", "Viscoat 8F", "Viscoat 8FM" manufactured by Osaka Organic Chemical Industry Co., Ltd., and those manufactured by Kyoeisha Chemical Co., Ltd. Examples thereof include "light ester M-3F".

Only one kind of reactive fluorine compound may be used, or two or more kinds may be used in combination. The proportion of the reactive fluorine compound in the monomer component is, for example, 1 to 10% by weight.

When the above-mentioned polar monomer and reactive fluorine compound are further contained as a monomer component, the ratio of each monomer in the monomer component is, for example, 8 to 35 weight by weight of (meth) acrylate having a linear alkyl group having 16 or more carbon atoms. %, Methyl (meth) acrylate at 10-85% by weight, dicyclopentanyl (meth) acrylate at 5-35% by weight, polar monomer at 1-10% by weight, and reactive fluorine compound at 1-10% by weight. is there.

Examples of the monomer polymerization method include a solution polymerization method, a massive polymerization method, a suspension polymerization method, and an emulsion polymerization method. When the solution polymerization method is adopted, the monomer and the solvent are mixed, a polymerization initiator, a chain transfer agent, etc. are added as necessary, and the reaction is carried out at about 40 to 90 ° C. for about 2 to 10 hours with stirring. Just let me do it.

The weight average molecular weight of the side chain crystalline polymer is, for example, 100,000 or more, preferably 300,000 to 900,000, and more preferably 400,000 to 700,000. The weight average molecular weight is a value obtained by measuring by gel permeation chromatography (GPC) and converting the obtained measured value into polystyrene.

The melting point of the side chain crystalline polymer is, for example, 0 ° C. or higher, preferably 10 to 60 ° C. The melting point can be adjusted by changing the composition of the side chain crystalline polymer or the like.

The temperature-sensitive pressure-sensitive adhesive of the present embodiment may further contain a cross-linking agent. Examples of the cross-linking agent include a metal chelate compound, an aziridine compound, an isocyanate compound, an epoxy compound and the like. The heat resistance can be improved by adopting a metal chelate compound among the exemplified cross-linking agents.

Examples of the metal chelate compound include a polyvalent metal acetylacetone coordination compound and a polyvalent metal acetoacetate coordination compound. Examples of the polyvalent metal include aluminum, nickel, chromium, iron, titanium, zinc, cobalt, manganese, zirconium and the like. Only one kind of metal chelate compound may be used, or two or more kinds may be used in combination. Among these, an acetylacetone coordination compound or an acetoacetic ester coordination compound of aluminum is preferable, and aluminum trisacetylacetonate is more preferable.

The content of the cross-linking agent is, for example, 0.1 to 10 parts by weight with respect to 100 parts by weight of the side chain crystalline polymer.

The cross-linking reaction can be carried out by adding a cross-linking agent to the temperature-sensitive pressure-sensitive adhesive and then heating it. Specifically, the temperature is about 90 to 110 ° C., and the time is about 1 minute to 20 minutes.

The form of use of the temperature-sensitive adhesive described above is not particularly limited, and may be used as it is, or may be used in the form of an adhesive sheet, an adhesive tape, or the like as described below.

<Temperature-sensitive adhesive sheet>
The temperature-sensitive pressure-sensitive adhesive sheet of the present embodiment contains the above-mentioned temperature-sensitive pressure-sensitive adhesive and is in the form of a base material-less sheet. The thickness of the temperature-sensitive pressure-sensitive adhesive sheet is, for example, 5 to 100 μm, preferably 5 to 50 μm.

A release film may be laminated on the surface of the temperature-sensitive adhesive sheet. Examples of the release film include a film made of polyethylene terephthalate or the like coated with a release agent such as silicone. The thickness of the release film is, for example, 5 to 500 μm, preferably 25 to 250 μm. The release film is peeled off when the temperature sensitive adhesive sheet is used.

<Temperature-sensitive adhesive tape>
The temperature-sensitive adhesive tape of the present embodiment includes a film-like base material and an adhesive layer laminated on at least one side of the base material. The film form is not limited to the film form, but is a concept including the film form or the sheet form as long as the effect of the present embodiment is not impaired.

Examples of the constituent materials of the base material include polyethylene, polyethylene terephthalate, polypropylene, polyester, polyamide, polyimide, polycarbonate, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, ethylene polypropylene copolymer, polyvinyl chloride and the like. Synthetic resin can be mentioned.

The structure of the base material may be either a single-layer structure or a multi-layer structure. The thickness of the base material is, for example, 5 to 500 μm, preferably 25 to 250 μm. The base material may be surface-treated in order to enhance the adhesion to the pressure-sensitive adhesive layer. Examples of the surface treatment include corona discharge treatment, plasma treatment, blast treatment, chemical etching treatment, primer treatment and the like.

The pressure-sensitive adhesive layer laminated on at least one side of the base material contains the above-mentioned temperature-sensitive pressure-sensitive adhesive. To laminate the pressure-sensitive adhesive layer on at least one side of the base material, for example, a solvent is added to a temperature-sensitive pressure-sensitive adhesive to prepare a coating liquid, and the obtained coating liquid is applied to one or both sides of the base material with a coater or the like. And dry it. Examples of the coater include a knife coater, a roll coater, a calendar coater, a comma coater, a gravure coater, a rod coater, and the like.

The thickness of the pressure-sensitive adhesive layer is, for example, 5 to 100 μm, preferably 5 to 50 μm.

When the pressure-sensitive adhesive layers are laminated on both sides of the base material, the pressure-sensitive adhesive layer on one side and the pressure-sensitive adhesive layer on the other side may have the same thickness, composition, etc., or may be different from each other. Good. Further, as long as the pressure-sensitive adhesive layer on one side is made of the temperature-sensitive pressure-sensitive adhesive described above, the pressure-sensitive adhesive layer on the other side is not particularly limited. The pressure-sensitive adhesive layer on the other surface can also be composed of, for example, a pressure-sensitive adhesive. Examples of the pressure-sensitive adhesive include natural rubber adhesives, synthetic rubber adhesives, styrene-butadiene latex-based adhesives, acrylic adhesives and the like.

A release film may be laminated on the surface of the temperature-sensitive adhesive tape. Examples of the release film include the same ones as exemplified in the above-mentioned temperature-sensitive adhesive sheet. The release film is peeled off when the temperature sensitive adhesive tape is used.

Hereinafter, the present invention will be described in detail with reference to Synthesis Examples and Examples, but the present invention is not limited to the following Synthesis Examples and Examples.

(Synthesis Examples 1 to 3 and Comparative Synthesis Example: Side Chain Crystalline Polymer)
First, the monomers shown in Table 1 were added to the reaction vessel at the ratios shown in Table 1. The monomers shown in Table 1 are as follows.
C18A: Stearyl acrylate C22A: Behenyl acrylate C1A: Methyl acrylate FA513AS: Dicyclopentanyl acrylate "FA-513AS" manufactured by Hitachi Chemical Co., Ltd.
AA: Acrylic acid V3F: Reactive fluorine compound "Viscoat 3F" manufactured by Osaka Organic Chemical Industry Co., Ltd., which is a 2,2,2-trifluoroethyl acrylate represented by the above formula (Ia).

Next, a mixed solvent of ethyl acetate: toluene = 75:25 (weight ratio) was added to the reaction vessel so that the solid content concentration became 30% by weight to obtain a mixed solution. Each monomer was copolymerized by stirring the obtained mixed solution at 55 ° C. for 4 hours to obtain a side chain crystalline polymer.

Table 1 shows the weight average molecular weight and melting point of each side chain crystalline polymer obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples. The weight average molecular weight is a polystyrene-converted value obtained by measuring with GPC. The melting point is a value measured using a DSC under measurement conditions of 10 ° C./min.

[Examples 1 to 5 and Comparative Examples 1 to 3]
<Making a temperature-sensitive adhesive sheet>
First, the tackifiers shown in Table 2 were mixed with 100 parts by weight of each side chain crystalline polymer obtained in Synthesis Examples 1 to 3 and Comparative Synthesis Examples at the ratio shown in Table 2. The tackifiers shown in Table 2 are as follows.
Styrene resin: "YS resin SX100" manufactured by Yasuhara Chemical Co., Ltd., which has a softening point of 95 to 105 ° C.
Rosin: Rosin ester "D-160" manufactured by Arakawa Chemical Industries, Ltd., which has a softening point of 150 to 170 ° C.

Next, a cross-linking agent was mixed at a ratio of 3 parts by weight with respect to 100 parts by weight of the side chain crystalline polymer to obtain a temperature-sensitive pressure-sensitive adhesive. The cross-linking agents used are as follows.
Cross-linking agent: Aluminum trisacetylacetone made by Kawaken Fine Chemicals, a metal chelate compound

Next, the obtained temperature-sensitive pressure-sensitive adhesive was adjusted with ethyl acetate so that the solid content concentration was 30% by weight, and a coating liquid was obtained. Then, the obtained coating liquid was applied onto a release film, and a crosslinking reaction was carried out under the conditions of 100 ° C. × 10 minutes to obtain a temperature-sensitive pressure-sensitive adhesive sheet having a thickness of 25 μm. As the release film, a polyethylene terephthalate film having a thickness of 50 μm having silicone coated on the surface was used.

<Evaluation>
The 180 ° peel strength and heat resistance were evaluated for each of the temperature-sensitive pressure-sensitive adhesive sheets obtained in Examples 1 to 5 and Comparative Examples 1 to 3. In addition, thermogravimetric analysis (TGA) was evaluated for each temperature-sensitive pressure-sensitive adhesive sheet obtained in Example 3 and Comparative Examples 1 to 3. Each evaluation method is shown below. The results of 180 ° peel strength and heat resistance are shown in Table 2, and the results of thermogravimetric analysis are shown in FIG.

(180 ° peel strength)
The 180 ° peel strength with respect to the polyimide film at 50 ° C., 200 ° C., 250 ° C. and 5 ° C. was measured according to JIS Z0237. Specifically, first, at an atmospheric temperature of 50 ° C., a temperature-sensitive adhesive sheet was attached to a glass plate using a 2 kg rubber roller. Next, the temperature-sensitive adhesive sheet was degassed under the conditions of 200 ° C. for 10 minutes. Then, the atmospheric temperature was lowered to 50 ° C., and a polyimide film was attached to the temperature-sensitive adhesive sheet at this atmospheric temperature to obtain a test piece.

After the obtained test piece was subjected to the following conditions, the polyimide film was peeled from the temperature-sensitive adhesive sheet by 180 ° at a speed of 300 mm / min using a load cell (n = 3).

[50 ° C]
The test piece was allowed to stand at an atmospheric temperature of 50 ° C. for 20 minutes and then peeled off by 180 °.

[200 ° C]
The test piece was placed on a hot plate at 200 ° C. for 20 minutes and then peeled off by 180 °.

[250 ° C]
The test piece was placed on a hot plate at 250 ° C. for 20 minutes and then peeled off by 180 °.

[5 ° C]
The test piece was placed on a hot plate at 250 ° C. for 1 hour, then placed on a cool plate at 5 ° C. for 20 minutes, and then peeled off by 180 °.

(Heat-resistant)
First, a test piece was obtained in the same manner as in the above-mentioned evaluation of 180 ° peel strength. Next, the obtained test piece was allowed to stand at 50 ° C. for 3 minutes and then heated in a hot air circulation oven at 250 ° C. for 30 minutes. Then, the heat resistance was evaluated by visually observing the state of the test piece at room temperature (23 ° C.). The evaluation criteria were set as follows.
〇: No floating was seen on the polyimide film.
X: Floating was observed on the polyimide film.

(Thermogravimetric analysis)
For each temperature-sensitive pressure-sensitive adhesive sheet obtained in Example 3 and Comparative Examples 1 to 3, the weight change with temperature change was measured. The measurement conditions are as follows.
Measuring equipment: "TG / DTA6200" manufactured by Hitachi High-Tech
Heating range: 30-300 ° C
Temperature rise rate: 10 ° C / min Others: Under a nitrogen atmosphere of 250 ml / min

As is clear from Table 2, Examples 1 to 5 have a high value of 180 ° peel strength at 50 to 250 ° C. and a low value of 180 ° peel strength at 5 ° C. after 250 ° C., resulting in heat resistance. Can be seen to be excellent. Further, as is clear from FIG. 1, it can be seen that Example 3 can suppress thermal deterioration when heated to a high temperature of 200 ° C. or higher, particularly 250 ° C. or higher.

Claims (7)

A temperature-sensitive pressure-sensitive adhesive that contains a side-chain crystalline polymer and whose adhesive strength decreases at a temperature lower than the melting point of the side-chain crystalline polymer.
The side chain crystalline polymer contains (meth) acrylate, methyl (meth) acrylate and dicyclopentanyl (meth) acrylate having a linear alkyl group having 16 or more carbon atoms as a monomer component.
A temperature-sensitive pressure-sensitive adhesive further containing a pressure-sensitive adhesive made of styrene resin. The temperature-sensitive pressure-sensitive adhesive according to claim 1, wherein the dicyclopentanyl (meth) acrylate is contained in a monomer component in a proportion of 5 to 35% by weight. The temperature-sensitive pressure-sensitive adhesive according to claim 1 or 2, wherein the pressure-sensitive adhesive is contained in a ratio of 20 to 50 parts by weight with respect to 100 parts by weight of the side chain crystalline polymer. The temperature-sensitive pressure-sensitive adhesive according to any one of claims 1 to 3, wherein the 180 ° peel strength with respect to the polyimide film at 5 ° C. after 1 hour at 250 ° C. is 0.15 N / 25 mm or less. The temperature-sensitive adhesive according to any one of claims 1 to 4, which is used for temporarily fixing a substrate in a manufacturing process of a flat panel display. A temperature-sensitive pressure-sensitive adhesive sheet containing the temperature-sensitive pressure-sensitive adhesive according to any one of claims 1 to 5. With a film-like base material
A temperature-sensitive adhesive tape comprising a pressure-sensitive adhesive layer laminated on at least one side of the base material and containing the temperature-sensitive pressure-sensitive adhesive according to any one of claims 1 to 5.

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