KR20180000694A - Thermosensitive resin, thermosensitive adhesive and thermosensitive adhesive composition - Google Patents

Abstract

The present invention provides a thermosensitive resin which has excellent heat resistance and chemical resistance, as well as high cohesion, and a thermosensitive adhesive and a thermosensitive adhesive composition which comprise the same. The thermosensitive resin according to the present invention is represented by formula (I), is crystallized at temperatures lower than a melting point thereof, and exhibits flowability at temperatures equal to or higher than the melting point. In the formula (I): R_1s are identical to or different from each other, and represent a C1-C10 hydrocarbon group; R_2 represents a group having an alkenyl group; R_3 represents a C12-C50 straight-chain alkyl group; m represents an integer of 2-10; n represents an integer of 1-100; x represents an integer of 0-2,000; y represents an integer of 100-2,000; and z represents an integer of 1-1,000.

Description

[0001] THERMOSENSITIVE RESIN, THERMOSENSITIVE ADHESIVE AND THERMOSENSITIVE ADHESIVE COMPOSITION [0002] This invention relates to a thermosensitive resin, a thermosensitive adhesive,

The present invention relates to a thermosensitive resin, a thermosensitive pressure-sensitive adhesive and a thermosensitive pressure-sensitive adhesive composition.

Sensitive thermosensitive resin having a thermosensitive property reversibly showing a crystalline state and a flow state in response to a temperature change is known (for example, Patent Documents 1 and 2). Since the thermosensitive resin is often used as a pressure-sensitive adhesive, it is preferable that it has excellent heat resistance and chemical resistance, and a high cohesive strength is also required.

Japanese Patent Application Laid-Open No. 2001-290138 Japanese Patent Application Laid-Open No. 2008-179744

A problem to be solved by the present invention is to provide a thermosensitive resin having excellent heat resistance and chemical resistance and having a high cohesive strength, and a thermosensitive pressure-sensitive adhesive and a thermosensitive pressure-sensitive adhesive composition containing the same.

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found a solution having the following constitution, and have completed the present invention.

(1) A thermosensitive resin represented by the following formula (I), which is crystallized at a temperature lower than the melting point and shows fluidity at a temperature higher than the melting point.

In the formula (I), R ₁ is the same or different and represents a hydrocarbon group of 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₃ represents a linear alkyl group having 12 to 50 carbon atoms. m represents an integer of 2 to 10; n represents an integer of 1 to 100; x represents an integer of 0 to 2,000. y represents an integer of 100 to 2000. and z represents an integer of 1 to 1000.

(2) The thermosensitive resin according to (1) above, wherein the melting point is not lower than 0 占 폚.

(3) A thermosensitive pressure-sensitive adhesive containing the thermosensitive resin according to (1) or (2), wherein the adhesive strength is lowered at a temperature lower than the melting point of the resin.

(4) A thermosensitive pressure-sensitive adhesive having a melting point of 0 ° C or higher.

(5) The thermosensitive adhesive according to (3) or (4), further comprising a polysiloxane having a Si-H group and a silanol-trimethylsilyl-modified MQ resin.

(6) A thermosensitive pressure-sensitive adhesive sheet comprising the thermosensitive adhesive according to any one of (3) to (5).

(7) A pressure-sensitive adhesive tape comprising a pressure-sensitive adhesive layer comprising the thermosensitive pressure-sensitive adhesive described in any one of (3) to (5) above laminated on at least one surface of a substrate.

(8) A thermosensitive pressure-sensitive adhesive composition comprising a thermosensitive resin according to (1) or (2), a polysiloxane having a Si-H group, a silanol-trimethylsilyl-modified MQ resin, and a Karstedt catalyst.

(Effects of the Invention)

According to the thermosensitive resin of the present invention, excellent heat resistance and chemical resistance are exhibited, and a high cohesive force is also exhibited. Such a thermosensitive resin is suitably used as a raw material for a thermosensitive pressure-sensitive adhesive and a thermosensitive pressure-sensitive adhesive composition.

<Thermosensitive Resin>

The thermosensitive resin according to one embodiment of the present invention will be described in detail. The thermosensitive resin of the present embodiment has a structure represented by formula (I).

In the formula (I), R ₁ is the same or different and represents a hydrocarbon group of 1 to 10 carbon atoms. The hydrocarbon group having 1 to 10 carbon atoms is not particularly limited and examples thereof include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group and hexyl group, alkenyl groups such as vinyl group, allyl group and butenyl group, And aryl groups such as a benzyl group, a phenethyl group, and a tolyl group. The alkyl group and the alkenyl group may have a straight chain structure or may have a branched structure.

In the formula (I), R ₂ represents a group having an alkenyl group. The group having an alkenyl group is a moiety having reactivity in the thermosensitive resin of the present embodiment. R ₂ is preferably a group having an alkenyl group having 2 to 10 carbon atoms. Specific examples of R ₂ include vinyl, allyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl and decenyl.

In the formula (I), R ₃ represents a linear alkyl group having 12 to 50 carbon atoms. The side chain moiety including the R ₃ , that is, the side chain moiety derived from the compound represented by the following formula (II) is a moiety having crystallinity in the thermosensitive resin of the present embodiment. The thermosensitive resin of the present embodiment is crystallized by aligning the side chains derived from the compound represented by the following formula (II) in an ordered arrangement by the intermolecular force or the like. R ₃ is preferably a straight chain alkyl group having from 14 to 30 carbon atoms, more preferably a straight chain alkyl group having from 18 to 30 carbon atoms. Specific examples of such alkyl groups include dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, octadecyl, eicosyl, docosyl, tetracosyl, A tetra-conyl group, and a pentacontyl group.

In the formula (I), x represents an integer of 0 to 2000, preferably an integer of 0 to 1500, more preferably an integer of 0 to 1000. y represents an integer of 100 to 2,000, preferably an integer of 100 to 1,500, and more preferably an integer of 200 to 1,500. z represents an integer of 1 to 1000, preferably an integer of 2 to 1000, more preferably an integer of 2 to 800.

In the formula (I), m represents an integer of 2 to 10, preferably an integer of 2 to 6, more preferably an integer of 2 or 3. n represents an integer of 1 to 100, preferably an integer of 1 to 40, more preferably an integer of 1 to 10.

The weight average molecular weight of the thermosensitive resin of the present embodiment is not particularly limited. The thermosensitive resin of the present embodiment preferably has a weight average molecular weight of 100,000 or more, more preferably 150,000 or more, preferably 2,000,000 or less, and more preferably 1,500,000 or less. The &quot; weight average molecular weight &quot; is a value obtained by measuring the thermosensitive resin by gel permeation chromatography (GPC) and converting the measured value into polystyrene.

The thermosensitive resin of the present embodiment has a melting point with respect to crystallization. Melting point &quot; means a temperature at which a certain portion of a polymer that has been initially aligned in an ordered arrangement by an equilibrium process becomes disordered, and is measured by a differential scanning calorimeter (DSC) at 10 ° C / min Means a value obtained by measurement. The thermosensitive resin of the present embodiment preferably has a melting point of 0 DEG C or higher, more preferably 10 DEG C or higher, and preferably has a melting point of 120 DEG C or lower, more preferably 100 DEG C or lower.

The thermosensitive resin of the present embodiment is crystallized at a temperature lower than the melting point and shows fluidity at the temperature higher than the melting point. That is, the thermosensitive resin of the present embodiment has a thermosensitive property reversibly showing the crystalline state and the flow state in response to the temperature change.

The thermosensitive resin of the present embodiment is a polysiloxane having a siloxane bond in its main chain as shown by the formula (I). Specifically, the thermosensitive resin of the present embodiment is a polyorganosiloxane having a reactive site R ₂ and a side chain derived from a compound represented by the formula (II) which is a crystalline site, and having a silicon skeleton. By such a constitution, excellent heat resistance and chemical resistance are exhibited. That is, since the conventional thermosensitive resin generally has an acrylic skeleton, it undergoes intensive hydrolysis in a chemical environment such as alkali or in a high temperature environment of 200 ° C or higher. Therefore, the conventional thermosensitive resin can not be used under the circumstances described above.

On the other hand, the thermosensitive resin of the present embodiment has a silicon skeleton as described above. As a result, heat resistance and chemical resistance can be exerted as compared with the conventional thermosensitive resin having an acrylic skeleton. In the thermosensitive resin of the present embodiment, the average degree of polymerization of the main chain siloxane is high and exceeds 100 (that is, x + y + z in formula (I) exceeds 100). Therefore, the thermosensitive resin of the present embodiment has a higher molecular weight as compared with the conventional thermosensitive resin, and exhibits a high cohesive force.

Next, an example of a method of manufacturing the thermosensitive resin of the present embodiment will be described. The thermosensitive resin of the present embodiment can be obtained, for example, by a ring-opening polymerization of cyclic siloxane to obtain a chain-like polysiloxane, and a side chain formed by addition reaction of the chain-like polysiloxane with a polysiloxane having linear? -Olefin and Si- And a side chain derived from a compound represented by the formula (II)). Hereinafter, one embodiment of the production method will be described by taking specific compounds as an example.

The cyclic siloxane is not particularly limited so long as it is a compound having a cyclic molecular structure by a siloxane bond. In the present embodiment, the compounds represented by the following formulas (III) and (III) 'will be described as an example.

(III), tetramethyltetravinylcyclotetrasiloxane represented by the formula (III) ', and a chain siloxane represented by the following formula (IV) as a terminal sealing agent with the following formula (V ) In the presence of a base catalyst.

R ₁ in the formula (IV) is the same or different and represents a hydrocarbon group of 1 to 10 carbon atoms, as described above. The hydrocarbon group having 1 to 10 carbon atoms is not particularly limited and examples thereof include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group and hexyl group, alkenyl groups such as vinyl group, allyl group and butenyl group, And aryl groups such as a benzyl group, a phenethyl group, and a tolyl group. The alkyl group and the alkenyl group may have a straight chain structure or may have a branched structure. and a represents an integer of 0 to 1000. Examples of the compound represented by the formula (IV) include compounds represented by the following formulas (IV) 'and (IV)''. Examples of the compound represented by the formula (IV) 'include 1,1,4,4-tetramethyl-1,1,4,4-tetravinyldisiloxane manufactured by Tokyo Kasei Kogyo Co., Ltd. and Gelest. &Quot; DMS-V21 &quot; (KF-96) manufactured by Shin-Etsu Chemical Co., Ltd., "hexamethyldisiloxane" and "octamethyltrisiloxane" manufactured by Tokyo Kasei Kogyo Co., Ltd., and the like Is commercially available.

In the compound represented by the following formula (V) used as a base catalyst, b represents an integer of 1 to 8. As the compound represented by the formula (V), for example, Gelest. &Quot; TETRAMETHYLAMMONIUM SILOXANOLATE &quot;

The base catalyst is not limited to the compound represented by the formula (V), but other base catalysts may be used. Examples of other base catalysts include tetrabutylammonium silanolate, tetramethylphosphonium silanolate, tetrabutylphosphonium silanolate, tetramethylium stibosilanolate, tetrabutylium stibosilanolate, tetrabutylammonium Silanolates of basic organic compounds such as silanolate, trimethylsulfonium silanolate, triethylsulfonium silanolate and the like, silanolates of strongly basic alkali metal hydroxides such as potassium silanolate and cesium silanolate, and the like .

The ring-opening polymerization is carried out by reacting octamethylcyclotetrasiloxane represented by the formula (III), tetramethyltetravinylcyclotetrasiloxane represented by the formula (III) ', the terminal sealing agent represented by the formula (IV) For example, about 0 to 120 캜, preferably about 70 to 120 캜, for about 0.1 to 48 hours, preferably about 0.5 to 24 hours. The reaction may be carried out in a solvent such as toluene, if necessary.

The mixing ratio of the octamethylcyclotetrasiloxane represented by the formula (III) and the tetramethyltetravinylcyclotetrasiloxane represented by the formula (III) 'is not particularly limited. For example, the siloxane represented by the formula (III) and the siloxane represented by the formula (III) 'are mixed at a molar ratio of 0: 1 to 5: 1, preferably 0: 1 to 2: 1. The end sealant is preferably added in a proportion of 0.00001 to 30 parts by mass based on 100 parts by mass of the mixture of the siloxane represented by the formula (III) and the formula (III) '. The base catalyst is added in a proportion of preferably 0.0000001 to 1 part by mass based on 100 parts by mass of the mixture of the siloxane represented by the formula (III) and the formula (III) '. Thus, a chain-like polysiloxane represented by the following formula (VI) is obtained. C in the formula (VI) represents an integer of 0 to 2000, and d represents an integer of 0 to 3,000. The chain polysiloxane represented by the formula (VI) uses a compound represented by the formula (IV) 'as a terminal sealing agent.

Next, the addition reaction will be described. First, a linear? -Olefin and a polysiloxane having Si-H groups at both terminals are reacted in the presence of a Karstedt catalyst represented by the following formula (VII). The resulting reaction product (the compound represented by the formula (II)) and the chain polysiloxane represented by the formula (VI) are reacted in the presence of a Karstedt catalyst represented by the formula (VII). The Karstedt catalyst may be a commercially available product, for example, &quot; Platinum (0) -1,3-divinyltetramethyldisiloxane complex &quot;, Gelest. SIP6831.2 &quot;, &quot; SIP6831.2LC &quot;, and the like are commercially available.

Examples of the linear? -Olefin include straight-chain? -Olefins having 12 to 50 carbon atoms. Of these, straight-chain? -Olefins having 14 to 30 carbon atoms are preferable, and straight-chain? -Olefins having 18 to 30 carbon atoms are more preferable. Specific examples of such linear? -Olefins include 1-octadecene represented by the following formula (VIII), 1-dodecene represented by the formula (VIII) 'and the like. The linear α-olefin may be a commercially available product. Examples of the linear α-olefin include linear α-olefin 18 (1-octadecene) and linear α-olefin 2024 (straight chain α- Mixture of olefins) &quot; and the like are commercially available.

Examples of the siloxane include a siloxane represented by the following formula (IX). R ₁ and n in the formula (IX) are as described above, and a description thereof will be omitted. Specific examples of the siloxane represented by the formula (IX) include tetramethyldisiloxane represented by the following formula (IX) '.

Specifically, the addition reaction is carried out in the following two-step reaction. First, a polysiloxane having a Si-H group at both terminals (formula (IX)) at a molar ratio of linear? -Olefin is added in a molar ratio of, for example, 1 to 20, preferably 4 to 10, and a Karstedt catalyst , For example, 10 to 100 ppm, preferably 10 to 50 ppm. Thereafter, the reaction is carried out at about 40 to 110 ° C, preferably about 50 to 70 ° C, for about 1 to 48 hours, preferably about 3 to 12 hours. The reaction may be carried out in a solvent such as toluene, if necessary. Thus, in the first-step reaction, the compound represented by the formula (II) is obtained.

Next, the obtained compound represented by the formula (II) and the chain polysiloxane represented by the formula (VI) are reacted in the presence of a Karstedt catalyst represented by the formula (VII). The linear polysiloxane represented by the formula (VI) is added in a molar ratio of, for example, 0.1 to 1, preferably 0.2 to 1, to the molar ratio of the compound represented by the formula (II), and the Karstedt catalyst is, for example, To 100 ppm, preferably 10 to 50 ppm. Thereafter, the reaction is carried out at about 40 to 110 ° C, preferably about 50 to 100 ° C, for about 1 to 48 hours, preferably about 3 to 6 hours. The reaction may be carried out in a solvent such as toluene, if necessary.

The reaction of the second step may be carried out by isolating the compound represented by the formula (II), and after the completion of the reaction of the first step, the compound represented by the formula (II) Or by adding a chain-like polysiloxane.

Thus, for example, when 1-octadecene represented by the formula (VIII) is used as the linear? -Olefin and tetramethyldisiloxane represented by the formula (IX) 'is used as the siloxane, the following formula (An example of the thermosensitive resin according to the present embodiment) is obtained. X, y and z in the formula (X) are as described above, and a description thereof will be omitted.

After the reaction, the reaction product may be used as a thermosensitive resin as it is, or the reaction product may be purified and used as a thermosensitive resin. As the purification method, for example, a method of removing an impurity, such as an olefin, which is an impurity, by solvent washing or re-precipitation may be mentioned. The solvent is not particularly limited, and examples thereof include acetone, a mixed solvent of toluene and acetone, and the like. Whether or not the impurities are removed can be confirmed by, for example, GPC or ¹ H-NMR.

&Lt; Temperature Sensitive Adhesive >

Next, the thermosensitive adhesive according to one embodiment of the present invention will be described in detail. The thermosensitive adhesive of the present embodiment contains the thermosensitive resin according to one embodiment described above and the adhesive strength is lowered at a temperature lower than the melting point of the thermosensitive resin. The thermosensitive pressure-sensitive adhesive of the present embodiment contains a thermosensitive resin in which the thermosensitive resin crystallizes at a temperature lower than the melting point and the adhesive force is lowered. Therefore, when the thermosensitive adhesive is peeled from the adherend, the thermosensitive adhesive is crystallized by cooling the thermosensitive adhesive to a temperature lower than the melting point of the thermosensitive resin, and the adhesive strength is lowered. On the other hand, when the thermosensitive adhesive is heated to a temperature higher than the melting point of the thermosensitive resin, the thermosensitive resin exhibits fluidity, thereby restoring the adhesive force. As a result, the thermosensitive adhesive of the present embodiment can be used repeatedly.

The thermosensitive adhesive of the present embodiment preferably includes polysiloxane having Si-H group and silanol-trimethylsilyl-modified MQ resin (hereinafter sometimes simply referred to as &quot; MQ resin &quot;).

The polysiloxane having a Si-H group can be cross-linked with the thermosensitive resin to be three-dimensional and can impart cohesive force to the thermosensitive resin. As a result, the adhesiveness of the thermosensitive adhesive can be further improved. The polysiloxane having a Si-H group is not particularly limited, and examples thereof include compounds represented by the following formulas (XI) to (XI) &quot;. In the formula (XI), f represents an integer of 0 to 2000. G in the formula (XI) 'represents an integer of 2 to 200. H in the formula (XI) &quot; represents an integer of 0 to 5000, and i represents an integer of 2 to 2000. HMS-501, HMS-013, HMS-031, HMS-064, HMS-013, and HMS-064 are commercially available products. Examples of the polysiloxane having Si- DMS-H31 "," DMS-H41 "and" DMS-H41 "(all of which are manufactured by Gelest. Inc.)," HMS-064 "," HMS-082 "," HMS-151 "," DMS- ) Are commercially available.

The MQ resin functions as a cohesive force component in the thermosensitive adhesive of the present embodiment. The MQ resin has a structure represented by the following formulas (XII), (XII) 'and the like, and usually has good compatibility with the above-mentioned thermosensitive resin. MQ resins may be commercially available, for example Gelest. Silmer VQ2012 "," Silmer VQ122XYL "," Silmer VQ9XYL ", etc., which are manufactured by Siltech Corporation, are commercially available.

When the thermosensitive adhesive of the present embodiment contains a polysiloxane having an Si-H group and an MQ resin, the content of each component is not particularly limited. For example, the polysiloxane having an Si-H group is contained in an amount of preferably 0.001 to 1000 parts by mass, more preferably 0.01 to 500 parts by mass based on 100 parts by mass of the thermosensitive resin. The MQ resin is contained in an amount of preferably 10 to 1000 parts by mass, more preferably 20 to 500 parts by mass based on 100 parts by mass of the thermosensitive resin.

The thermosensitive adhesive of the present embodiment may be applied directly to an adherend, or may be used in the form of a sheet in the form of a substrate-less sheet, and the mode of use is not particularly limited. For example, when the thermosensitive adhesive of the present embodiment is used as the thermosensitive adhesive sheet, the thickness of the thermosensitive adhesive sheet is preferably 10 to 500 mu m, more preferably 10 to 200 mu m.

The thermosensitive adhesive of the present embodiment may be used in the form of a tape. When the thermosensitive adhesive of the present embodiment is used as the thermosensitive adhesive tape, the pressure sensitive adhesive layer containing the thermosensitive adhesive of this embodiment is laminated on at least one side of the substrate. The substrate is preferably in the form of a film, and a sheet is also included on the film.

Examples of the constituent material of the substrate include polyethylene, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyester, polyamide, polyimide, polyamideimide, polycarbonate, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, Ethylene polypropylene copolymer, polyvinyl chloride, polyether ether ketone, and the like.

The base material may have a single-layer structure or a multi-layer structure. The substrate usually has a thickness of about 5 to 500 mu m. The substrate may be subjected to surface treatment such as corona discharge treatment, plasma treatment, blast treatment, chemical etching treatment, primer treatment or the like for the purpose of improving adhesion to the pressure-sensitive adhesive layer.

The method of laminating the pressure-sensitive adhesive layer on at least one surface of the substrate is not particularly limited. For example, a method in which a coating solution prepared by adding a solvent to a thermosensitive pressure-sensitive adhesive is coated on one side or both sides of a substrate by a coater or the like and dried. Examples of the coater include a knife coater, a roll coater, a calendar coater, a comma coater, a gravure coater, and a road coater.

A Karstedt catalyst for crosslinking reaction is usually added to the coating liquid, and a prohibiting agent for suppressing the reaction before coating may be added. As a result, the inhibitor and the Karstedt catalyst form a complex to prevent the crosslinking reaction from occurring in the pressure-sensitive adhesive layer. If the inhibitor is volatilized by heating above the boiling point of the inhibitor, the crosslinking reaction proceeds through the Karstedt catalyst. Examples of the inhibitor include 1-butyne-2-ol, 2-methyl-3-butyne-2-ol, 3,5- Phenylbutynol, 1-ethynyl-1-cyclohexanol, and the like.

The Karstedt catalyst is added to the thermosensitive resin so that the concentration of platinum is preferably in the range of 1 to 1000 ppm. On the other hand, the inhibitor is added in an amount of preferably 1 to 5 parts by mass based on 100 parts by mass of the thermosensitive resin. The constitution of the coating liquid is the same also in the case where the thermosensitive adhesive is applied directly to an adherend or when it is used in the form of a sheet of base-less lease.

The pressure-sensitive adhesive layer preferably has a thickness of 1 to 100 占 퐉, more preferably 5 to 80 占 퐉, and still more preferably 10 to 60 占 퐉. When the pressure-sensitive adhesive layer is laminated on both sides of the substrate, the thickness of the pressure-sensitive adhesive layer may be the same or different, and the composition of the pressure-sensitive adhesive forming the pressure-sensitive adhesive layer may be the same or different.

If a pressure sensitive adhesive containing the thermosensitive adhesive of the present embodiment is laminated on one side of the substrate, another pressure sensitive adhesive layer may be laminated on the other side. For example, an adhesive layer containing a pressure-sensitive adhesive may be laminated on the other side. The pressure-sensitive adhesive includes a polymer having adhesiveness. Examples of such a polymer having adhesiveness include natural rubber adhesives, synthetic rubber adhesives, styrene / butadiene latex base adhesives, acrylic adhesives, and the like.

It is preferable to laminate a release film on the surface of the thermosensitive adhesive sheet and the thermosensitive adhesive tape of the present embodiment. Examples of the release film include a film made of polyethylene terephthalate coated on the surface of a releasing agent such as fluorosilicone.

<Temperature Sensitive Adhesive Composition>

Next, the thermosensitive adhesive composition according to one embodiment of the present invention will be described in detail. The thermosensitive adhesive of the present embodiment contains a thermosensitive resin according to one embodiment, a polysiloxane having Si-H group, a silanol-trimethylsilyl-modified MQ resin, and a Karstedt catalyst. If necessary, the inhibitor may be added. The details of each component are as described above, and a description thereof will be omitted.

As described above, the thermosensitive resin according to one embodiment of the present invention has excellent heat resistance, chemical resistance, and high cohesive strength. The use of a thermosensitive pressure-sensitive adhesive containing such a thermosensitive resin is not particularly limited, and is suitably used as a pressure-sensitive adhesive in a field where heat resistance and chemical resistance are required, for example.

The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present invention. For example, in the above-described embodiment, the thermosensitive adhesive containing the thermosensitive resin, the polysiloxane having Si-H group, and the MQ resin has been described as an example. However, as long as the thermosensitive pressure-sensitive adhesive contains the above-mentioned thermosensitive resin, it is not limited to the constitution containing the polysiloxane having the Si-H group and the MQ resin, and it can be constituted of a general material used for a so-

(Example)

Hereinafter, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to these examples.

(Synthesis Example 1: Synthesis of chain-like polysiloxane)

20 g of cyclic siloxane and 400 mg of end sealant were added to a three-necked flask equipped with a stirring blade and a nitrogen introduction tube. "Tetravinyltetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" was used as the cyclic siloxane, and "DMS-21 (Gelest., Inc)" was used as the end sealer. Nitrogen was introduced into the mixture of the cyclic siloxane and the end sealant from a nitrogen introduction tube and nitrogen bubbling was performed for 30 minutes while stirring. Subsequently, the nitrogen introduction tube was separated from the mixture, and the three-necked flask was placed in an oil bath. 7 mg of "TETRAMETHYLAMMONIUM SILOXANOLATE (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" as a base catalyst was added to a three-necked flask, and the mixture was stirred at 100 ° C for 6 hours. Then, the temperature was raised to 150 ° C in order to decompose the catalyst, and the mixture was further stirred for 3 hours. After completion of the reaction, the reaction mixture was cooled to room temperature to obtain a chain polysiloxane (A) represented by the formula (VI). The chain polysiloxane (A) obtained from the GPC measurement had a number average molecular weight of 55,000 and a weight average molecular weight of 137,000. The number average molecular weight and the weight average molecular weight were obtained by measuring the obtained chain polysiloxane with GPC and converting the measured value into polystyrene.

(Synthesis Example 2: Synthesis of chain-like polysiloxane)

A chain-like polysiloxane (B) was obtained in the same manner as in Synthesis Example 1 except that the amount of the end sealant (DMS-21) was changed to 100 mg. The chain polysiloxane (B) obtained from the GPC measurement had a number average molecular weight of 77,000 and a weight average molecular weight of 218000.

(Synthesis Example 3: Synthesis of chain-like polysiloxane)

Hexamethylcyclotetrasiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was used as the cyclic siloxane and 4 g of tetravinyltetramethylcyclotetrasiloxane as the cyclic siloxane, and 200 mg of &quot; hexamethyldisiloxane &quot; (C) was obtained in the same manner as in Synthesis Example 1, except that the amount of the cyclic polysiloxane (C) was changed to &quot; The chain polysiloxane (C) obtained from the GPC measurement had a number average molecular weight of 60,000 and a weight average molecular weight of 126,000.

(Synthesis Example 4: Synthesis of long-chain alkyl unit)

To a three-necked flask equipped with a stirrer and a thermometer, 108.8 g of "tetramethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", 50 g of "1-Dococene (manufactured by Tokyo Kasei Kogyo Co., Ltd.) Dehydrated toluene was added. The three-necked flask was placed in an oil bath and heated to 70 DEG C with stirring. When the temperature reached 70 占 폚, 50 mg of a 20 mass% toluene solution of "platinum (0) -1,3-divinyltetramethyldisiloxane complex (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" was added. Then, the mixture was stirred at 70 DEG C for 24 hours. Then, a Dean-Stark apparatus was attached to the three-necked flask, and the unreacted tetramethyldisiloxane was recovered by heating at 100 DEG C for 3 hours. Subsequently, the reaction mixture in the three-necked flask was dropped into ethanol to perform precipitation purification. The precipitate was recovered by suction filtration and dried under reduced pressure at 80 캜 to obtain a long-chain alkyl unit having one end reactivity represented by the formula (II).

(Example 1)

&Lt; Synthesis of side chain crystalline polysiloxane (thermosensitive resin) >

In a three-necked flask equipped with a stirrer, 3 g of the chain polysiloxane (A) obtained in Synthesis Example 1, 14.3 g of the long chain alkyl unit obtained in Synthesis Example 4, and 40 g of dehydrated toluene were added. The three-necked flask was placed in an oil bath and heated to 100 DEG C with stirring using a magnetic stirrer. When the temperature reached 100 占 폚, 60 mg of a 20 mass% toluene solution of "platinum (0) -1,3-divinyltetramethyldisiloxane complex" was added. Then, the mixture was stirred at 100 占 폚 for 24 hours. Subsequently, 100 g of a mixed solvent of toluene and acetone (weight ratio 3: 7) was heated to 60 DEG C, and the resulting mixture was added to the reaction mixture and stirred. The work of removing the solvent with decantation was repeated three times, and a precipitate was obtained. The resulting precipitate was dried under reduced pressure at 80 캜 to obtain a side chain crystalline polysiloxane (1).

The side chain crystalline polysiloxane (1) obtained from the GPC measurement had a number average molecular weight of 103000 and a weight average molecular weight of 503000. The number average molecular weight and the weight average molecular weight were obtained by measuring the obtained side chain crystalline polysiloxane with GPC and converting the obtained measured value into polystyrene. ^The side chain crystalline polysiloxane (1) obtained from the integral ratio of ¹ H-NMR contained the vinylmethylsiloxane unit in a proportion of about 3%. In addition, the side chain crystalline polysiloxane (1) obtained from the DSC measurement (10 占 폚 / min) had a melting point of about 37 占 폚.

<Preparation of thermosensitive pressure-sensitive adhesive>

The resulting side chain crystalline polysiloxane (1), MQ resin, and polysiloxane having Si-H groups were mixed in the ratios shown in Table 1 to prepare a thermosensitive pressure-sensitive adhesive. The polysiloxane and MQ resin having Si-H group used are as follows.

HMS-064 &quot; and &quot; HMS-082 &quot; (both manufactured by Gelest. Inc.) Represented by the above formula (XI)

MQ resin: &quot; VQX-221 &quot; (manufactured by Gelest. Inc.) Represented by the above formula (XII)

&Lt; Production of pressure sensitive adhesive tape >

Toluene was added to 100 parts by mass of the obtained thermosensitive pressure-sensitive adhesive so as to have a solid content concentration of 70% by mass. To this was added 0.5 part by mass of the above-mentioned &quot; platinum (0) -1,3-divinyltetramethyldisiloxane complex &quot; in terms of solid content, and 1 part by mass of 2-methyl- By weight to prepare a coating liquid. The obtained coating liquid was applied to one side of a polyethylene terephthalate film (thickness 75 mu m), that is, the side subjected to the fluorosilicon treatment. Subsequently, the resultant was heated at 120 占 폚 for 10 minutes to crosslink the reactive site (vinyl group) of the side chain crystalline polysiloxane and the reactive site (vinyl group) of the MQ resin and the functional group (Si-H group) of the polysiloxane having Si-H group. Thus, a thermosensitive adhesive tape having a pressure-sensitive adhesive layer (thickness of 30 mu m) was obtained.

(Example 2)

Side chain crystalline polysiloxane (2) was obtained in the same manner as in Example 1, except that 3 g of the chain-like polysiloxane (B) obtained in Synthesis Example 2, 15 g of the long-chain alkyl unit obtained in Synthesis Example 4 and 42 g of dehydrated toluene were used. The number average molecular weight, the weight average molecular weight, the ratio of the vinyl methyl siloxane unit, and the melting point of the side chain crystalline polysiloxane (2) obtained in the same procedure as in Example 1 were measured. The results are shown below.

Number average molecular weight: 124000

Weight average molecular weight: 513000

Vinyl methyl siloxane unit ratio: about 10%

Melting point: about 39 캜

A thermosensitive pressure-sensitive adhesive was prepared in the same manner as in Example 1 except that the side chain crystalline polysiloxane (2) was used. A thermosensitive pressure-sensitive adhesive tape was produced in the same manner as in Example 1 except that the thermosensitive pressure-sensitive adhesive was used.

(Example 3: synthesis of side chain crystalline polysiloxane)

Side chain crystalline polysiloxane (3) was obtained in the same manner as in Example 1 except that 3 g of the chain polysiloxane (C) obtained in Synthesis Example 3 was used. The number average molecular weight, the weight average molecular weight, the proportion of the vinyl methyl siloxane unit, and the melting point of the side chain crystalline polysiloxane (3) obtained in the same procedure as in Example 1 were measured. The results are shown below.

Number average molecular weight: 102000

Weight average molecular weight: 322000

Vinyl methyl siloxane unit ratio: about 25%

Melting point: about 31 캜

A thermosensitive pressure-sensitive adhesive was prepared in the same manner as in Example 1 except that the side chain crystalline polysiloxane (3) was used. A thermosensitive pressure-sensitive adhesive tape was produced in the same manner as in Example 1 except that the thermosensitive pressure-sensitive adhesive was used.

(Comparative Example 1)

Sensitive adhesive tape was produced in the same manner as in Example 1 except that a thermosensitive adhesive made of a thermosensitive resin containing an acryl skeleton was used in place of the thermosensitive adhesive obtained in Example 1. [ The monomer composition, melting point and weight average molecular weight of the acryl-skeleton-containing thermosensitive resin are as follows.

Monomer composition: behenyl acrylate / methyl acrylate / acrylic acid = 45 parts by mass / 50 parts by mass / 5 parts by mass

Melting point: about 55 캜

Weight average molecular weight: 540000

The heat sensitive adhesive tape obtained in Examples 1 to 3 and Comparative Example 1 was evaluated for the 180 ° peel strength, heat resistance and chemical resistance by the following methods. The results are shown in Table 2.

<180 ° peel strength>

The 180 占 peeling strength against the polyimide under the atmosphere of 80 占 폚 and 5 占 폚 was measured according to JIS Z0237. Specifically, the thermosensitive adhesive tape was adhered to an alkali-free glass under the following conditions, and then peeled at 180 ° at a speed of 300 mm / min using a load cell.

(80 DEG C)

Sensitive adhesive tape was adhered to an alkali-free glass in an atmosphere of 80 DEG C, and the polyethylene terephthalate film was peeled off. Thereafter, a rectangular polyimide film (25 mu m in thickness and 25 mm in width) was adhered and allowed to stand at 80 DEG C for 20 minutes and peeled off at 180 DEG.

(5 DEG C)

Sensitive adhesive tape was adhered to an alkali-free glass in an atmosphere of 80 DEG C, and the polyethylene terephthalate film was peeled off. Thereafter, a rectangular polyimide film (25 mu m in thickness and 25 mm in width) was adhered and allowed to stand at 80 DEG C for 20 minutes. Subsequently, the substrate was cooled to 5 占 폚, allowed to stand for 20 minutes, and then peeled off at 180 占 폚.

<Heat resistance>

And evaluated by thermogravimetric analysis (TGA). More specifically, the temperature was raised from 25 ° C to 500 ° C (10 ° C / min) under a nitrogen gas atmosphere by using a thermogravimetric analyzer "TG / DTA 6200" manufactured by Seiko Instruments Inc., And the mass change of the side chain crystalline polysiloxane was measured. Then, the temperature at the time when the mass became 98% with respect to the mass at 25 DEG C, that is, the 2% mass reduction temperature was measured. The higher the temperature, the better the heat resistance.

<Chemical resistance>

Sensitive adhesive tape was immersed in a 10 mass% aqueous sodium hydroxide solution at 23 占 폚 for 10 minutes. Thereafter, the state of the thermosensitive adhesive tape was evaluated based on the following criteria.

(Evaluation standard)

O: The thermosensitive adhesive tape did not swell.

X: The thermosensitive adhesive tape swelled.

As shown in Table 2, it can be seen that the thermosensitive adhesive tapes obtained in Examples 1 to 3 have excellent chemical resistance and 180 degree peel strength. In addition, the side chain crystalline polysiloxane (thermosensitive resin) obtained in Examples 1 to 3 has a high 2% weight reduction temperature and excellent heat resistance.

Claims (8)

A thermosensitive resin represented by the following formula (I), which is crystallized at a temperature lower than the melting point and shows fluidity at a temperature higher than the melting point.

In the formula (I), R ₁ is the same or different and represents a hydrocarbon group of 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₃ represents a linear alkyl group having 12 to 50 carbon atoms. m represents an integer of 2 to 10; n represents an integer of 1 to 100; x represents an integer of 0 to 2,000. y represents an integer of 100 to 2000. and z represents an integer of 1 to 1000. The method according to claim 1,
Wherein the melting point is not lower than 0 占 폚. A thermosensitive pressure-sensitive adhesive containing the thermosensitive resin according to any one of claims 1 to 3, wherein the adhesive strength is lowered at a temperature lower than the melting point of the resin. The method of claim 3,
Sensitive adhesive having a melting point of 0 ° C or higher. The method according to claim 3 or 4,
A siloxane-polysiloxane having a Si-H group, and a silanol-trimethylsilyl-modified MQ resin. Sensitive adhesive sheet comprising the thermosensitive adhesive according to any one of claims 3 to 5. Sensitive adhesive tape according to any one of claims 3 to 5, wherein the pressure-sensitive adhesive layer comprising the thermosensitive pressure-sensitive adhesive is laminated on at least one surface of the substrate. A thermosensitive pressure-sensitive adhesive composition comprising the thermosensitive resin according to claim 1 or 2, the polysiloxane having Si-H group, the silanol-trimethylsilyl-modified MQ resin, and the Karstedt catalyst.