KR102328925B1 - Thermosensitive resin, thermosensitive adhesive and thermosensitive adhesive composition - Google Patents

Abstract

식 (I) 중, R₁은 동일하거나 또는 다르고 탄소수 1∼10의 탄화수소기를 나타낸다. R₂는 알케닐기를 갖는 기를 나타낸다. R₁은 동일하거나 또는 다르고 탄소수 1∼10의 탄화수소기를 나타낸다. R₂는 알케닐기를 갖는 기를 나타낸다. R₃은 탄소수 2∼11의 폴리메틸렌기를 나타낸다. R₄는 하기 식 (II)로 나타내어지는 구조를 갖는 메소겐기를 나타낸다. m은 2∼10의 정수를 나타낸다. n은 1∼100의 정수를 나타낸다. x는 0∼2000의 정수를 나타낸다. y는 100∼2000의 정수를 나타낸다. z는 2∼1000의 정수를 나타낸다.

식 (II) 중, R₅는 수소, 탄소수 1∼10의 지방족 탄화수소기, 탄소수 6∼18의 방향족 탄화수소기, 탄소수 1∼10의 알콕시기, 또는 시아노기를 나타낸다.(Project) To provide a thermosensitive resin having excellent heat resistance and chemical resistance, and a thermosensitive adhesive and a thermosensitive adhesive composition containing the same.
(Solution) The thermosensitive resin according to the present invention is represented by the following formula (I), crystallizes at a temperature below the melting point, and exhibits fluidity at a temperature above the melting point.

In formula (I), R ₁ is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₁ is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₃ represents a polymethylene group having 2 to 11 carbon atoms. R ₄ represents a mesogenic group having a structure represented by the following formula (II). m represents the integer of 2-10. n represents the integer of 1-100. x represents the integer of 0-2000. y represents the integer of 100-2000. z represents the integer of 2-1000.

In formula (II), R<_5> represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a C6-C18 aromatic hydrocarbon group, a C1-C10 alkoxy group, or a cyano group.

Description

Temperature-sensitive resin, temperature-sensitive adhesive, and temperature-sensitive adhesive composition TECHNICAL FIELD

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

Thermosensitive resins having temperature sensitivity that reversibly show a crystalline state and a fluid state in response to a temperature change are known (for example, Patent Documents 1 and 2). Since the thermosensitive resin is often used as an adhesive, it is preferable to have excellent heat resistance and chemical resistance.

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

An object of the present invention is to provide a thermosensitive resin having excellent heat resistance and chemical resistance, and a thermosensitive adhesive and a thermosensitive adhesive composition containing the same.

MEANS TO SOLVE THE PROBLEM The present inventors found the solution which consists of the following structures, as a result of earnestly examining in order to solve the said subject, and came to complete this invention.

(1) A thermosensitive resin represented by the following formula (I), which crystallizes at a temperature below the melting point and exhibits fluidity at a temperature above the melting point.

In formula (I), R ₁ is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₃ represents a polymethylene group having 2 to 11 carbon atoms. R ₄ represents a mesogenic group having a structure represented by the following formula (II). m represents the integer of 2-10. n represents the integer of 1-100. x represents the integer of 0-2000. y represents the integer of 100-2000. z represents the integer of 2-1000.

In formula (II), R<_5> represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a C6-C18 aromatic hydrocarbon group, a C1-C10 alkoxy group, or a cyano group.

(2) The thermosensitive resin according to (1), wherein the mesogenic group has a structure represented by the following formula (II)' or (II)".

(3) The thermosensitive resin according to (1) or (2), wherein the melting point is 0°C or higher.

(4) A temperature-sensitive adhesive comprising the temperature-sensitive resin according to any one of (1) to (3), and whose adhesive force decreases at a temperature lower than the melting point of the resin.

(5) The temperature-sensitive adhesive according to (4) above, wherein the melting point is 0°C or higher.

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

(7) A thermosensitive adhesive sheet containing the thermosensitive adhesive according to any one of (4) to (6).

(8) The temperature-sensitive adhesive tape in which the adhesive layer containing the temperature-sensitive adhesive as described in any one of said (4)-(6) was laminated|stacked on at least one surface of a base material.

(9) A temperature-sensitive adhesive composition comprising the temperature-sensitive resin according to any one of (1) to (3), a polysiloxane having a Si-H group, a silanol-trimethylsilyl-modified MQ resin, and a Karstedt catalyst.

(Effects of the Invention)

ADVANTAGE OF THE INVENTION According to the thermosensitive resin of this invention, the outstanding heat resistance and chemical-resistance are exhibited. Such a temperature-sensitive resin is suitably used as a raw material for a temperature-sensitive adhesive and a temperature-sensitive adhesive composition.

<Temperature-sensitive resin>

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

In formula (I), R ₁ is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms. The hydrocarbon group having 1 to 10 carbon atoms is not particularly limited, and for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group and a hexyl group, a vinyl group, an allyl group, an alkenyl group such as a butenyl group, and a phenyl group and aryl groups such as benzyl group, phenethyl group and tolyl group. An alkyl group or an alkenyl group may have a linear structure, and may have a branched structure.

In formula (I), R<_2> represents group which has an alkenyl group. The group having this alkenyl group is a site 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 a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, and a decenyl group.

In formula (I), R<_3> represents a C2-C11 polymethylene group. The _{side chain moiety containing R 3} , that is, the side chain moiety derived from the compound represented by the following formula (III) is a moiety having crystallinity in the thermosensitive resin of the present embodiment. The thermosensitive resin of the present embodiment crystallizes when the side chains derived from the compound represented by the following formula (III) are aligned in an orderly arrangement by molecular force or the like. Specific examples of the polymethylene group having 2 to 11 carbon atoms include a dimethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, and a hexamethylene group.

In formula (I), R<_4> represents the mesogenic group which has a structure represented by following formula (II). The mesogenic group means a rigid and high orientation group that contributes to liquid crystal expression. In formula (II), R<_5> represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a C6-C18 aromatic hydrocarbon group, a C1-C10 alkoxy group, or a cyano group.

Examples of the aliphatic hydrocarbon group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, an octyl group, and a decyl group. Examples of the aromatic hydrocarbon group having 6 to 18 carbon atoms include a phenyl group, a benzyl group, a biphenyl group, and a terphenyl group. Examples of the alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, a butoxy group, an octyloxy group, a decyloxy group, a diethoxy group, a triethoxy group, and a tetraethoxy group. R ₅ is preferably an n-butyl group or a methoxy group. A mesogenic group having a structure represented by the formula (II) in which R ₅ is an n-butyl group or a methoxy group is represented by the following formulas (II)' and (II)".

In formula (I), x represents the integer of 0-2000, Preferably the integer of 0-1500 is shown, More preferably, the integer of 0-1000 is shown. y represents the integer of 100-2000, Preferably the integer of 100-1500 is shown, More preferably, the integer of 200-1500 is shown. z represents the integer of 2-1000, Preferably the integer of 2-1000 is shown, More preferably, the integer of 2-800 is shown.

Moreover, in Formula (I), m represents the integer of 2-10, Preferably the integer of 2-6 is shown, More preferably, the integer of 2-3 is shown. n represents the integer of 1-100, Preferably the integer of 2-40 is shown, More preferably, the integer of 2-10 is shown.

The weight average molecular weight of the thermosensitive resin of this embodiment is not specifically limited. The thermosensitive resin of this embodiment becomes like this. Preferably it is 100,000 or more, More preferably, it has a weight average molecular weight of 150,000 or more, Preferably it has a weight average molecular weight of 2 million or less, More preferably, it has a weight average molecular weight of 1.5 million or less. The "weight average molecular weight" is the 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" means the temperature at which a specific part of the polymer, which was initially aligned in an orderly arrangement, becomes disordered by a predetermined equilibrium process, measured by differential thermal scanning calorimetry (DSC) at 10°C/min. means the value obtained. The thermosensitive resin of the present embodiment preferably has a melting point of 0°C or higher, more preferably 10°C or higher, and preferably 120°C or lower, more preferably 100°C or lower.

The thermosensitive resin of the present embodiment crystallizes at a temperature below the melting point, and exhibits fluidity due to a phase transition at a temperature above the melting point. That is, the thermosensitive resin of this embodiment has temperature sensitivity which shows a crystalline state and a fluid state reversibly in response to a temperature change.

The thermosensitive resin of this embodiment is polysiloxane which has a siloxane bond in a principal chain, as represented by Formula (I). Specifically, the thermosensitive resin of the present embodiment _{is a polyorganosiloxane having a side chain derived from a compound represented by R 2} as a reactive moiety and Formula (III) as a crystalline moiety, and having a silicone skeleton. By such a structure, the outstanding heat resistance and chemical-resistance are exhibited. That is, since conventional thermosensitive resins usually have an acrylic skeleton, they are violently hydrolyzed in a chemical environment such as alkali or in a high temperature environment of 200°C or higher. Therefore, the conventional thermosensitive resin cannot be used under the circumstances described above.

On the other hand, the thermosensitive resin of this embodiment has a silicone skeleton as mentioned above. As a result, heat resistance and chemical resistance superior to conventional thermosensitive resins having an acrylic skeleton are exhibited. The thermosensitive resin of this embodiment can be used also in the high temperature environment of 250 degreeC or more, for example.

Next, an example of the method of manufacturing the thermosensitive resin of this embodiment is demonstrated. The thermosensitive resin of this embodiment obtains a chain polysiloxane by, for example, ring-opening polymerization of cyclic siloxane, and a side chain formed with siloxane and a mesogenic group by an addition reaction to this chain polysiloxane (to the compound represented by the formula (III) derived side chain). Hereinafter, one embodiment of a manufacturing method is demonstrated taking a specific compound as an example.

Cyclic siloxane will not be specifically limited if it is a compound which has a cyclic molecular structure by a siloxane bond. In the present embodiment, the compounds represented by the following formulas (IV) and (IV)' will be described as examples.

Octamethylcyclotetrasiloxane represented by the formula (IV), tetramethyltetravinylcyclotetrasiloxane represented by the formula (IV)', and the chain siloxane represented by the following formula (V) as a terminal blocker were mixed with the following formula ( The reaction may be carried out in the presence of a base catalyst represented by VI).

_{R 1} in the formula (V) is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms as described above. The hydrocarbon group having 1 to 10 carbon atoms is not particularly limited, and for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group and a hexyl group, a vinyl group, an allyl group, an alkenyl group such as a butenyl group, and a phenyl group and aryl groups such as benzyl group, phenethyl group and tolyl group. An alkyl group or an alkenyl group may have a linear structure, and may have a branched structure. a represents an integer of 0 to 1000, and examples of the compound represented by the formula (V) include compounds represented by the following formulas (V)' and (V)”. As a represented compound, "1,1,4,4-tetramethyl-1,1,4,4-tetravinyldisiloxane" manufactured by Tokyo Kasei Kogyo Co., Ltd. or "DMS-" manufactured by Gelest. Inc. V21" etc. are commercially available. As a compound represented by (V)", for example, "KF-96" manufactured by Shin-Etsu Kagaku Kogyo Co., Ltd., and "hexamethyldisiloxane" manufactured by Tokyo Kasei Kogyo Co., Ltd. and "Octamethyltrisiloxane" are commercially available.

In the compound represented by the following formula (VI) used as a base catalyst, b represents an integer of 1 to 8. As a compound represented by Formula (VI), Gelest. Inc. "TETRAMETHYLAMMONIUM SILOXANOLATE" etc. are marketed.

The base catalyst is not limited to the compound represented by the formula (V), and other base catalysts may be used. Examples of the other base catalyst include tetrabutylammonium silanorate, tetramethylphosphonium silanorate, tetrabutylphosphonium silanorate, tetramethylstivoniumsilanorate, tetrabutylstivoniumsilanorate, tetrabutylar. Silanorate of basic organic compounds such as sonium silanorate, trimethylsulfonium silanorate, triethylsulfonium silanorate, etc., silanorate of strong basic alkali metal hydroxides such as potassium silanorate and cesium silanorate, etc. can be heard

The ring-opening polymerization is carried out with the octamethylcyclotetrasiloxane represented by the formula (IV), the tetramethyltetravinylcyclotetrasiloxane represented by the formula (IV)', the terminal blocker represented by the formula (V), and the formula (VI) ) is reacted, for example, at about 0 to 120°C, preferably about 70 to 120°C for about 0.1 to 48 hours, preferably for about 0.5 to 24 hours. You may perform reaction in solvents, such as toluene, as needed.

The mixing ratio of the octamethylcyclotetrasiloxane represented by Formula (IV) and the tetramethyltetravinylcyclotetrasiloxane represented by Formula (IV)' is not specifically limited. For example, the siloxane represented by the formula (IV) and the siloxane represented by the formula (IV)' are mixed in a molar ratio of 0:1 to 5:1, preferably 0:1 to 2:1. The terminal blocker is preferably added in an amount of 0.00001 to 30 parts by mass with respect to 100 parts by mass of the mixture of siloxanes represented by the formulas (IV) and (IV)'. The base catalyst is preferably added in an amount of 0.0000001 to 1 part by mass with respect to 100 parts by mass of the mixture of siloxanes represented by the formulas (IV) and (IV)'. In this way, the chain polysiloxane represented by the following formula (VII) is obtained. c in Formula (VII) represents the integer of 0-2000, and d represents the integer of 0-3000. The chain polysiloxane represented by the formula (VII) uses the compound represented by the formula (V)' as a terminal blocker.

Next, the addition reaction will be described. First, a compound generating a mesogenic group having a structure represented by the above formula (II) 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). Thereafter, the obtained reactant (compound represented by the above formula (III)) and the chain polysiloxane represented by the formula (VII) are reacted in the presence of a Karstedt catalyst represented by the formula (VIII). A Karstedt catalyst may use a commercial item, For example, Tokyo Kasei Kogyo Co., Ltd. product "platinum (0)-1,3-divinyl tetramethyldisiloxane complex", Gelest. Inc. "SIP6831.2", "SIP6831.2LC", etc. are marketed.

As a compound which generate|occur|produces the mesogenic group which has a structure represented by Formula (II), the compound represented by following formula (IX) is mentioned, for example. In formula (IX), R<_5> is as above-mentioned, and description is abbreviate|omitted. R ₆ represents an alkenyl group having 2 to 11 carbon atoms. Among the compounds that generate a mesogenic group having a structure represented by formula (II), compounds represented by the following formula (IX)' or (IX)” are preferable.

As siloxane, the siloxane represented by following formula (X) is mentioned, for example. _{R 1} and n in formula (X) are as described above, and description is omitted. Specific examples of the siloxane represented by the formula (X) include tetramethyldisiloxane represented by the following formula (X)'.

The addition reaction is specifically carried out in the following two-step reaction. First, the polysiloxane (formula (X)) having Si-H groups at both terminals with respect to the compound molar ratio 1 represented by the formula (IX) is, for example, 1 to 20, preferably 4 to 10 in a molar ratio of 1 and Karstedt catalyst is added in a proportion of, for example, 10 to 100 ppm, preferably 10 to 50 ppm. After that, the reaction is carried out at about 40 to 110 deg. C, preferably at about 50 to 70 deg. C for about 1 to 48 hours, preferably for about 3 to 12 hours. If necessary, the reaction may be performed in a solvent such as toluene. In this way, the compound represented by the above-mentioned formula (III) is obtained in the reaction of the 1st step.

Next, the obtained compound represented by Formula (III) and the chain polysiloxane represented by Formula (VII) are reacted in the presence of a Karstedt catalyst represented by Formula (VIII). The chain polysiloxane represented by the formula (VII) is added in a molar ratio of, for example, 0.1 to 1, preferably 0.2 to 1, with respect to a molar ratio of 1 of the compound represented by the formula (III), and Karstedt catalyst is added, for example It is added in a proportion of 10 to 100 ppm, preferably 10 to 50 ppm. After that, the reaction is carried out at about 40 to 110 deg. C, preferably at about 50 to 100 deg. C for about 1 to 48 hours, preferably about 3 to 6 hours. You may perform reaction in solvents, such as toluene, as needed.

The second step reaction may be performed by isolating the compound represented by formula (III), and after completion of the first step reaction, the compound represented by formula (III) is added to the reaction mixture as formula (VII) without isolating You may add and carry out the chain|strand-shaped polysiloxane shown.

In this way, for example, when the compound represented by the formula (IX)' is used as the compound represented by the formula (IX) and the tetramethyldisiloxane represented by the formula (X)' is used as the siloxane, the following formula A side chain crystalline polysiloxane represented by (XI) (an example of the thermosensitive resin according to the present embodiment) is obtained. The x, y, and z of the formula (XI) are the same as described above, and a description thereof will be omitted.

After the reaction, the reactant may be used as it is as a thermosensitive resin, or the reactant may be purified and used as a thermosensitive resin. As a purification method, the method etc. which remove the asymmetric olefin etc. which are impurities by solvent washing|cleaning or reprecipitation are mentioned, for example. It does not specifically limit as a solvent, For example, acetone, the mixed solvent of toluene, and acetone, etc. are mentioned. Whether or not impurities have been removed may ^{be confirmed by, for example, GPC, 1} H-NMR, or the like.

<Temperature Sensitive Adhesive>

Next, the thermosensitive adhesive by one Embodiment of this invention is demonstrated in detail. The thermosensitive adhesive of this embodiment contains the thermosensitive resin by one Embodiment mentioned above, and adhesive force falls at the temperature below melting|fusing point of the thermosensitive resin. The thermosensitive adhesive of this embodiment contains the thermosensitive resin which crystallizes at the temperature below melting|fusing point, and adhesive force falls. Therefore, when peeling a temperature-sensitive adhesive from a to-be-adhered body, when a temperature-sensitive adhesive is cooled to the temperature below melting|fusing point of the thermosensitive resin, the thermosensitive resin will crystallize and adhesive force will fall. On the other hand, when the temperature-sensitive adhesive is heated to a temperature equal to or higher than the melting point of the temperature-sensitive resin, the temperature-sensitive resin exhibits fluidity, thereby restoring adhesive strength. As a result, the thermosensitive adhesive of this embodiment can be used repeatedly.

The temperature-sensitive adhesive of the present embodiment preferably includes polysiloxane having a Si-H group and a silanol-trimethylsilyl-modified MQ resin (hereinafter, simply referred to as “MQ resin” in some cases).

Polysiloxane having a Si-H group can undergo a crosslinking reaction with the temperature-sensitive resin to make it three-dimensional, and to impart cohesive force to the temperature-sensitive resin. As a result, the adhesiveness of a temperature-sensitive adhesive can be improved more. The polysiloxane having a Si-H group is not particularly limited, and examples thereof include compounds represented by the following formulas (XII) to (XII)". In formula (XII), f represents an integer of 0 to 2000. In formula (XII)', g represents an integer of 2 to 200. In formula (XII)", h represents an integer of 0 to 5000, and i represents an integer of 2 to 2000. A commercially available product may be used for the polysiloxane having Si-H group, for example, "HMS-991", "HMS-013", "HMS-031", "HMS-064", "HMS-071", "HMS- 064", "HMS-082", "HMS-151", "HMS-501", "DMS-H11", "DMS-H21", "DMS-H31", "DMS-H41" (all made by Gelest. Inc.) ) are commercially available.

MQ resin functions as a cohesive force component in the thermosensitive adhesive of this embodiment. MQ resin has a structure represented by the following formulas (XIII) and (XIII)', and usually has good compatibility with the above-mentioned thermosensitive resin. As the MQ resin, a commercially available product may be used, for example, Gelest. Inc. "SQO-299", "VQX-221", "Silmer VQ20", "Silmer VQ2012", "Silmer VQ122XYL", "Silmer VQ9XYL" by Siltech Corpration, etc. are marketed.

When the thermosensitive adhesive of this embodiment contains the polysiloxane which has Si-H group, and MQ resin, content of each component is not specifically limited. For example, to 100 mass parts of thermosensitive resin polysiloxane which has Si-H group, Preferably it is 0.001-1000 mass parts, More preferably, it contains in the ratio of 0.01-500 mass parts. With respect to 100 mass parts of thermosensitive resins, MQ resin becomes like this. Preferably it is 10-1000 mass parts, More preferably, it contains in the ratio of 20-500 mass parts.

The thermosensitive adhesive of this embodiment may apply|coat directly to a to-be-adhered body, for example, may use it in the form of the sheet form of a base material lease, and a use form is not specifically limited. For example, when using the thermosensitive adhesive of this embodiment as a thermosensitive adhesive sheet, the thickness of a thermosensitive adhesive sheet becomes like this. Preferably it is 10-500 micrometers, More preferably, it is 10-200 micrometers.

You may use the thermosensitive adhesive of this embodiment in the form of a tape shape. When using the thermosensitive adhesive of this embodiment as a thermosensitive adhesive tape, the adhesive layer containing the thermosensitive adhesive of this embodiment is laminated|stacked on at least one surface of a base material. The substrate is preferably in the form of a film, and the film form also includes a sheet form.

As a constituent material of the base material, for example, polyethylene, polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyester, polyamide, polyimide, polycarbonate, ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer, ethylene polypropylene Synthetic resins, such as a copolymer, polyvinyl chloride, and polyether ether ketone, are mentioned.

The base material may have a single layer structure, and may have a multilayer structure. The substrate usually has a thickness of about 5 to 500 µm. In addition, for the purpose of improving the adhesiveness to an adhesive layer, the surface treatment, such as corona discharge treatment, a plasma treatment, a blast treatment, a chemical etching process, a primer treatment, may be given to a base material, for example.

The method of laminating|stacking an adhesive layer on at least one surface of a base material is not specifically limited. For example, the method of apply|coating the coating liquid which added the solvent to the temperature sensitive adhesive on the single side|surface or both surfaces of a base material with a coater etc., and drying, etc. are mentioned. As a coater, a knife coater, a roll coater, a calender coater, a comma coater, a gravure coater, a rod coater etc. are mentioned, for example.

A Karstedt catalyst for crosslinking reaction is normally added to a coating liquid, and the inhibitor for suppressing reaction before application|coating may be added. Thereby, the inhibitor and Karstedt catalyst form a complex, and it can suppress that a crosslinking reaction arises in an adhesive layer. When the inhibitor is volatilized by heating above the boiling point of the inhibitor, a crosslinking reaction through the Karstedt catalyst proceeds. As the inhibitor, for example, 1-butyn-2-ol, 2-methyl-3-butyn-2-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentene-3 -ol, phenylbutynol, 1-ethynyl-1-cyclohexanol, etc. are mentioned.

The Karstedt catalyst is added to the thermosensitive resin so that the concentration of platinum is preferably 1 to 1000 ppm. On the other hand, the inhibitor is preferably added in an amount of 1 to 5 parts by mass with respect to 100 parts by mass of the thermosensitive resin. The composition of the coating liquid is the same also in the case where the temperature-sensitive adhesive is applied directly to the adherend and used, or when used in the form of a base material lease sheet.

An adhesive layer becomes like this. Preferably it is 1-100 micrometers, More preferably, it is 5-80 micrometers, More preferably, it has a thickness of 10-60 micrometers. When the pressure-sensitive adhesive layer is laminated on both surfaces 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.

In addition, if the adhesive containing the thermosensitive adhesive of this embodiment is laminated|stacked on one surface of a base material, another adhesive layer may be laminated|stacked on the other surface. For example, the adhesive layer containing a pressure-sensitive adhesive may be laminated|stacked on the other surface. The pressure-sensitive adhesive includes a polymer having tackiness. Examples of the polymer having such adhesiveness include a natural rubber adhesive, a synthetic rubber adhesive, a styrene/butadiene latex-based adhesive, and an acrylic adhesive.

It is preferable to laminate|stack a release film on the surface of the temperature-sensitive adhesive sheet and temperature-sensitive adhesive tape of this embodiment. As a release film, the polyethylene terephthalate film etc. by which the mold release agent like fluorosilicone was apply|coated on the surface are mentioned, for example.

<Temperature-sensitive adhesive composition>

Next, the thermosensitive adhesive composition by one Embodiment of this invention is demonstrated in detail. The temperature-sensitive adhesive of the present embodiment contains the temperature-sensitive resin according to the above-described embodiment, a polysiloxane having a Si-H group, a silanol-trimethylsilyl-modified MQ resin, and a Karstedt catalyst. The above-mentioned inhibitor may be added as needed. Details of each component are the same 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 and chemical resistance. The use of the thermosensitive adhesive containing such a thermosensitive resin is not particularly limited, and for example, it is suitably used as an adhesive in a field requiring heat resistance and chemical resistance.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the embodiment described above, a temperature-sensitive adhesive containing a temperature-sensitive resin, a polysiloxane having a Si-H group, and an MQ resin has been described as an example. However, the temperature-sensitive adhesive is not limited to a configuration containing a polysiloxane having a Si-H group and an MQ resin as long as it contains the above-mentioned temperature-sensitive resin, and can be composed of a general material used for so-called silicone-based adhesives.

(Example)

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated concretely, this invention is not limited to these Examples.

(Synthesis Example 1: Synthesis of chain polysiloxane)

To a three-necked flask equipped with a stirring blade and a nitrogen inlet tube, 20 g of cyclic siloxane and 5 mg of an end sealant were added. "Tetravinyltetramethylcyclotetrasiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" was used as the cyclic siloxane, and "hexamethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" was used as the terminal blocker. Nitrogen was introduced into the mixture of the cyclic siloxane and the end-blocking agent from a nitrogen introduction tube, and nitrogen bubbling was performed for 30 minutes while stirring. Then, the nitrogen inlet tube was separated from the mixture, and the three-necked flask was placed in an oil bath. As a base catalyst, 7 mg of "TETRAMETHYLAMMONIUM SILOXANOLATE (manufactured by Tokyo Kasei Kogyo Co., Ltd.)" was added to a three-necked flask, followed by stirring at 100°C for 6 hours. Next, in order to decompose|disassemble the catalyst, it heated up to 150 degreeC and stirred for 3 hours further. After completion of the reaction, it was cooled to room temperature to obtain a chain polysiloxane represented by the formula (VII). From the GPC measurement, the obtained chain polysiloxane had a number average molecular weight of 55000 and a weight average molecular weight of 137000. A number average molecule and a weight average molecular weight were obtained by measuring the obtained chain|strand-shaped polysiloxane by GPC, and carrying out polystyrene conversion of the obtained measured value.

(Synthesis Example 2: Synthesis of liquid crystal molecules (compounds generating mesogenic groups))

Put a stirrer into a flask equipped with a cooling tube, 20 g of "4-Allyloxybenzaidehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", 18.4 g of "4-Butylaniline (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", and 40 g of ethanol was added The flask was placed in an oil bath, and the temperature was raised to 80° C. while stirring using a magnetic stirrer, followed by reaction for 24 hours. Then, the reaction mixture was left still, cooled to room temperature, purified by recrystallization, and yellow crystals were recovered by suction filtration. The recovered crystals were dried under reduced pressure at 100°C for 4 hours to obtain a compound (A) that generates a mesogenic group represented by the formula (IX)'. From the DSC measurement (10°C/min), the obtained compound (A) had a melting point of about 69°C and a clearing point of about 53°C.

(Synthesis Example 3: Synthesis of liquid crystal molecules (compounds generating mesogenic groups))

Put a stirrer into a flask with a cooling tube attached to it, 20 g of "4-Allyloxybenzaidehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", 15.2 g of "p-Anisidine (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", and 40 g of toluene was added The flask was placed in an oil bath, and the temperature was raised to 100°C while stirring using a magnetic stirrer, followed by reaction for 12 hours. Then, the reaction mixture was left still, cooled to room temperature, purified by recrystallization, and yellow crystals were recovered by suction filtration. The recovered crystals were dried under reduced pressure at 120° C. for 4 hours to obtain a compound (B) that generates a mesogenic group represented by formula (IX)”. From the DSC measurement (10° C./min), the obtained compound (B) is about It had a melting point of 112°C.

(Synthesis Example 4: Synthesis of mesogen unit)

To a three-neck flask equipped with a stirring blade and a thermometer, 45.8 g of "tetramethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", 10 g of the compound (A) obtained in Synthesis Example 2, and 82 g of dehydrated toluene were added. . The three-necked flask was placed in an oil bath, and the temperature was raised to 70°C while stirring. When it became 70 degreeC, 10 mg of 20 mass % toluene solution of "platinum (0)-1,3-divinyl tetramethyldisiloxane complex (made by Tokyo Kasei Kogyo Co., Ltd.)" was added. Then, it stirred at 70 degreeC for 24 hours. Next, a Dean-Stark apparatus was attached to the three-necked flask, and it heated at 100 degreeC for 3 hours, and unreacted tetramethyldisiloxane was collect|recovered. Next, the reaction mixture in the three neck flask was dripped in ethanol, and precipitation purification was performed. The precipitate was collected by suction filtration and dried under reduced pressure at 80°C to obtain a one-terminal reactive mesogen unit (A)' represented by the formula (III).

(Synthesis Example 5: Synthesis of mesogenic unit)

One end in the same procedure as in Synthesis Example 4, except that 50.2 g of "tetramethyldisiloxane (manufactured by Tokyo Kasei Kogyo Co., Ltd.)", 10 g of the compound (B) obtained in Synthesis Example 3, and 90.3 g of dehydrated toluene were used. A reactive mesogenic unit (B)' was obtained.

(Example 1: Synthesis of side chain crystalline polysiloxane (temperature-sensitive resin))

To a three-neck flask equipped with a stirrer, 1 g of the chain polysiloxane obtained in Synthesis Example 1, 4.72 g of the mesogen unit (A)' obtained in Synthesis Example 4, and 13.4 g of dehydrated toluene were added. The three-necked flask was placed in an oil bath, and the temperature was raised to 100°C while stirring using a magnetic stirrer. When it became 100 degreeC, 6 mg of 20 mass % toluene solution of "platinum (0)-1,3-divinyl tetramethyldisiloxane complex" was added. Then, it stirred at 100 degreeC for 24 hours. Then, 50 g of acetone heated to 60° C. was added to the obtained reaction mixture and stirred. The operation of removing the solvent by decantation was repeated three times to obtain a precipitate. The obtained precipitate was dried under reduced pressure at 80°C to obtain branched-chain crystalline polysiloxane (1).

From the GPC measurement, the obtained side chain crystalline polysiloxane (1) had a number average molecular weight of 109000 and a weight average molecular weight of 281000. A number average molecule and a weight average molecular weight were obtained by measuring the obtained side chain crystalline polysiloxane by GPC, and carrying out polystyrene conversion of the obtained measured value. ^From the integral ratio of 1 H-NMR, the obtained branched-chain crystalline polysiloxane (1) contained vinylmethylsiloxane units in a proportion of about 10%. Further, from the DSC measurement (10°C/min), the obtained branched-chain crystalline polysiloxane (1) had a melting point of about 40°C.

About the obtained side chain crystalline polysiloxane (1), the heat resistance was evaluated by thermogravimetric analysis (TGA). Specifically, using a thermogravimetric analyzer "TG/DTA 6200" manufactured by Seiko Instruments Inc., the temperature was raised from 25° C. to 500° C. (10° C./min) in a nitrogen gas atmosphere, in the process The mass change of the side chain crystalline polysiloxane (1) was measured. Next, the temperature at the time when the mass became 98% with respect to the mass at 25 degreeC, ie, the 2% mass decrease temperature, was measured. It shows that it is excellent in heat resistance, so that this temperature is high. A result is shown in Table 1.

(Example 2: Synthesis of side chain crystalline polysiloxane (temperature-sensitive resin))

Branched chain crystalline polysiloxane (2) was obtained in the same manner as in Example 1 except that 4.43 g of the mesogenic unit (B)' obtained in Synthesis Example 5 and 12.7 g of dehydrated toluene were used. In the same procedure as in Example 1, the number average molecular weight, weight average molecular weight, ratio of vinylmethylsiloxane units, and melting point of the obtained side chain crystalline polysiloxane (2) were measured. A result is shown below.

Number average molecular weight: 97000

Weight average molecular weight: 270000

Proportion of vinylmethylsiloxane units: about 12%

Melting point: about 66℃

For the obtained side chain crystalline polysiloxane (2), heat resistance was evaluated in the same manner as in Example 1. A result is shown in Table 1.

(Comparative Example 1)

The heat resistance was evaluated in the same manner as in Example 1 about the acrylic skeleton-containing thermosensitive resin having the following monomer composition. A result is shown in Table 1.

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

Melting point: about 55℃

Weight average molecular weight: 540000

As shown in Table 1, it turns out that the side chain crystalline polysiloxane (temperature-sensitive resin) obtained in Examples 1 and 2 has a high 2% mass loss temperature and has excellent heat resistance. On the other hand, it can be seen that the acrylic skeleton-containing thermosensitive resin obtained in Comparative Example 1 has a low 2% mass loss temperature and lacks heat resistance.

(Example 3: Preparation of temperature-sensitive adhesive sheet)

The obtained side chain crystalline polysiloxane (1), the polysiloxane which has Si-H group, and MQ resin were mixed in the ratio shown in Table 2, and the thermosensitive adhesive was prepared. The polysiloxane and MQ resin which have Si-H group used are as follows.

Polysiloxane having a Si-H group: "HMS-064" represented by "the formula (XII)" (manufactured by Gelest. Inc.)

MQ resin: "SQO-299" represented by the formula (XIII) (manufactured by Gelest. inc)

Toluene was added to 100 mass parts of the obtained thermosensitive adhesive so that solid content concentration might be set to 70 mass %. There, 0.5 mass part of said "platinum (0)-1,3-divinyltetramethyldisiloxane complex" in terms of solid content, and 2-methyl-3-butyn-2-ol as an inhibitor in terms of solid content of 1 It added in the ratio of mass parts, and the coating liquid was prepared. The obtained coating liquid was apply|coated to the single side|surface of a polyethylene terephthalate film (75 micrometers in thickness), ie, the surface to which the fluorosilicone process was given. Then, it heated at 120 degreeC for 10 minutes, and crosslinked the reactive site (vinyl group) of the side chain crystalline polysiloxane and the functional group (Si-H group) of the polysiloxane having a Si-H group. Thus, the temperature-sensitive adhesive sheet in which the adhesive layer (30 micrometers in thickness) was formed was obtained.

(Example 4: Preparation of temperature-sensitive adhesive sheet)

As shown in Table 2, a temperature-sensitive adhesive sheet was obtained in the same manner as in Example 3 except that side chain crystalline polysiloxane (2) was used instead of side chain crystalline polysiloxane (1).

(Comparative Example 2: Preparation of temperature-sensitive adhesive sheet)

Toluene was added to 100 parts by mass of the acrylic skeleton-containing thermosensitive resin obtained in Comparative Example 1 so that the solid content concentration was 30% by mass. A coating liquid was prepared by mixing 5 parts by mass of tritylamine as an inhibitor and 1 part by mass of "PZ-33" (manufactured by Nippon Shokubai Co., Ltd.) as a crosslinking agent. The obtained coating liquid was apply|coated to the single side|surface of a polyethylene terephthalate film (50 micrometers in thickness), ie, the surface to which silicone treatment was performed. Then, it heated at 100 degreeC for 10 minutes, and obtained the thermosensitive adhesive sheet in which the crosslinked adhesive layer (30 micrometers in thickness) was formed.

About the temperature-sensitive adhesive sheet obtained in Examples 3 and 4 and Comparative Example 2, the 180 degree peeling strength and chemical-resistance were evaluated by the following method. A result is shown in Table 3.

<180° peel strength>

The 180 degree peeling strength with respect to the polyimide in 80 degreeC and 5 degreeC atmosphere was measured based on JISZ0237. Specifically, after affixing a temperature-sensitive adhesive sheet to alkali-free glass on the following conditions, it peeled 180 degrees at a speed|rate of 300 mm/min using a load cell.

(80℃)

The temperature-sensitive adhesive sheet was affixed to alkali-free glass in 80 degreeC atmosphere, and the polyethylene terephthalate film was peeled. Then, the rectangular polyimide film (25 micrometers in thickness, and 25 mm in width) was affixed, and it left still at 80 degreeC for 20 minutes, and it peeled 180 degrees.

(5℃)

The temperature-sensitive adhesive sheet was affixed to alkali-free glass in 80 degreeC atmosphere, and the polyethylene terephthalate film was peeled. Then, the rectangular polyimide film (25 micrometers in thickness and 25 mm in width) was affixed, and it left still at 80 degreeC for 20 minutes. Then, after cooling to 5 degreeC and leaving it still for 20 minutes, it peeled 180 degrees.

<Chemical resistance>

The temperature-sensitive adhesive sheets obtained in Examples 3 and 4 and Comparative Example 2 were cut into rectangular shapes to obtain test pieces (2 cm x 5 cm). The obtained test piece was immersed in the chemical|medical agent mixed solution containing 55 mass % phosphoric acid, 25 mass % acetic acid, and 20 mass % water, and it left still at 70 degreeC for 15 minutes. After 15 minutes, the test piece was taken out from the chemical mixture solution, washed with water, and whether or not a whitening part or a discolored part existed in the temperature-sensitive adhesive sheet was visually observed.

As shown in Table 3, from the results of the 180° peel strength test, the temperature-sensitive adhesive sheets obtained in Examples 3 and 4 had an acrylic skeleton-containing temperature-sensitive resin at a temperature (80° C.) higher than the melting point of the side-chain crystalline polysiloxane (temperature-sensitive resin). It can be seen that it has sufficient adhesive force and excellent fixability. On the other hand, it turns out that adhesive force is falling to the grade which can peel easily at the temperature (5 degreeC) below melting|fusing point of side chain crystalline polysiloxane.

Moreover, even if it immersed in the chemical|medical agent mixed solution, the temperature-sensitive adhesive sheet obtained in Examples 3 and 4 did not produce a whitening part or a discoloration part, but it turns out that it is excellent also also about chemical-resistance. On the other hand, when the temperature-sensitive adhesive sheet obtained in Comparative Example 2 was immersed in a chemical mixture solution, a whitening portion was formed, and it was found that the chemical resistance was insufficient.

Claims (9)

A thermosensitive resin represented by the following formula (I), which crystallizes at a temperature below the melting point, and exhibits fluidity at a temperature above the melting point.

In formula (I), R ₁ is the same or different and represents a hydrocarbon group having 1 to 10 carbon atoms. R ₂ represents a group having an alkenyl group. R ₃ represents a polymethylene group having 2 to 11 carbon atoms. R ₄ represents a mesogenic group having a structure represented by the following formula (II). m represents the integer of 2-10. n represents the integer of 1-100. x represents the integer of 0-2000. y represents the integer of 100-2000. z represents the integer of 1-1000.

In formula (II), R<_5> represents hydrogen, a C1-C10 aliphatic hydrocarbon group, a C6-C18 aromatic hydrocarbon group, a C1-C10 alkoxy group, or a cyano group. The method of claim 1,
A thermosensitive resin having a structure in which the mesogenic group is represented by the following formula (II)' or (II)".

3. The method according to claim 1 or 2,
A temperature-sensitive resin having a melting point of 0°C or higher. A temperature-sensitive adhesive comprising the temperature-sensitive resin according to claim 1 or 2, wherein the adhesive strength decreases at a temperature lower than the melting point of the resin. 5. The method of claim 4,
A temperature-sensitive adhesive having a melting point of 0°C or higher. 5. The method of claim 4,
A temperature-sensitive adhesive further comprising a polysiloxane having a Si-H group and a silanol-trimethylsilyl-modified MQ resin. A thermosensitive adhesive sheet comprising the thermosensitive adhesive according to claim 4 . The temperature-sensitive adhesive tape in which the adhesive layer containing the thermosensitive adhesive of Claim 4 was laminated|stacked on at least one surface of a base material. A temperature-sensitive adhesive composition comprising the temperature-sensitive resin according to claim 1 or 2, a polysiloxane having a Si-H group, a silanol-trimethylsilyl-modified MQ resin, and a Karstedt catalyst.