WO2023013678A1

WO2023013678A1 - Easy-heat-disassembly adhesive composition or thermally decomposable binder composition

Info

Publication number: WO2023013678A1
Application number: PCT/JP2022/029807
Authority: WO
Inventors: 章一松本
Original assignee: 公立大学法人大阪
Priority date: 2021-08-06
Filing date: 2022-08-03
Publication date: 2023-02-09
Also published as: JPWO2023013678A1

Abstract

The present invention addresses the problem of developing a binder or an adhesive having superior easy-disassembly properties or decomposition properties while having sufficient adhesiveness prior to being heated.　The above problem is solved by an easy-heat-disassembly adhesive composition or a thermally decomposable binder composition containing a (meth)acrylic-acid-ester-based polymer that includes a (meth)acrylic-acid-ester-based monomer unit having a tertiary alkoxycarbonyloxy group at a terminal, and a thermal acid generator.

Description

Heat-dismantling adhesive composition or heat-decomposable binder composition

The present invention provides a heat-dismantling adhesive composition or a heat-decomposing binder composition, an adhesive product containing the heat-dismantling pressure-sensitive adhesive composition, a product containing the heat-dismantling binder composition, a ceramic sintered body, and a screen-printed material. or to a method of manufacturing a product selected from multilayer ceramic capacitors. Specifically, an easily dismantling adhesive composition comprising a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at its end, and a thermal acid generator. Or it relates to a thermally decomposable binder composition.

In recent years, for the purpose of reducing the amount of waste, there is an increasing demand for reusing fixed objects fixed on adherends with adhesives. In that case, it is necessary to use an easily dismantled adhesive that can fix the fixed object on the adherend when the fixed object is used, and can easily separate the fixed object from the adherend when the fixed object is reused. Become. In recent years, with the rapid miniaturization, sophistication, and speedup of communication equipment and electronic equipment such as smartphones, digital cameras, personal computers, televisions, and Blu-ray recorders, electronic parts and electronic devices have become smaller and denser.・High integration is required. The binder used for these is desired to be a binder that is thermally decomposed into volatile components during the sintering process and does not produce a carbon-containing residue while having the properties of a binder.
Attempts have been made on such easily dismantling pressure-sensitive adhesives and binders. A tacky adhesive composition is disclosed that is capable of Japanese Patent Application Laid-Open No. 2017-186184 (Patent Document 2) discloses a binder containing a copolymer having a polyvinyl butyral main chain and a polyacrylic acid graft chain.
However, the adhesive adhesive composition that can be peeled off by light cannot be used for materials that cannot be irradiated with light or materials that cannot be irradiated with light due to their structure. Removal of the carbon component after heating was not sufficient.

JP-A-2004-043732 Japanese Patent Application Laid-Open No. 2017-186184 Japanese Patent Application Laid-Open No. 2019-210405 Japanese Patent Application Laid-Open No. 2020-012013

The inventors have repeatedly studied adhesives and binders that are easily dismantled and decomposable by a method different from light, and have found that by using a polymer that decomposes when heated, an adhesive that is easily dismantled and decomposable. and developed a binder [Japanese Patent Application Laid-Open No. 2019-210405 (Patent Document 3), Japanese Patent Application Laid-Open No. 2020-012013 (Patent Document 4)]. However, it has been desired to develop a pressure-sensitive adhesive or a binder that has sufficient adhesiveness before heating and also has superior easy dismantling and decomposability.

As a result of intensive studies, the inventors of the present invention have found that a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at its end, and a thermal acid generator. By producing a thermally decomposable adhesive composition or a thermally decomposable binder composition using the composition, the polymer is rapidly decomposed by heating while having sufficient adhesiveness/adhesiveness and stability before heating. The inventors have found that the tackiness/adhesiveness can be reduced, leading to the present invention.
Thus, the present invention provides an easily dismantling adhesive comprising a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a terminal tertiary alkoxycarbonyloxy group, and a thermal acid generator. A thermally decomposable binder composition is provided.
According to the present invention, there is provided an adhesive product having an adhesive layer containing the easily dismantleable adhesive composition.
According to the present invention, there is provided a product comprising the thermally decomposable binder composition.
Furthermore, according to the present invention, there is provided a method for manufacturing a product selected from a ceramic sintered body, a screen-printed product, or a laminated ceramic capacitor, wherein the mixture comprises a member constituting the product and the above-described thermally decomposable binder composition. and heating the coated or shaped mixture to decompose the binder.

According to the present invention, a heat-dismantling pressure-sensitive adhesive composition capable of rapidly decomposing a polymer by heating to rapidly reduce the pressure-sensitive adhesiveness/adhesiveness while having sufficient pressure-sensitive adhesiveness and stability before heating, or A thermally decomposable binder composition can be provided.

FIG. 1 shows the ¹ H-NMR spectrum of BHEA. FIG. 1 shows the ¹ H-NMR spectrum of BHBA. FIG. 1 shows the ¹ H-NMR spectrum of BHEMA; FIG. 1 shows the ¹ H-NMR spectrum of PBHEA. FIG. 1 shows the ¹ H-NMR spectrum of PBHBA. FIG. 1 shows the ¹ H-NMR spectrum of PBHEMA; FIG. 2 shows the ¹ H-NMR spectrum of P(BHBA-co-HBA). FIG. 1 shows the ¹ H-NMR spectrum of P(BHEA-co-2EHA-co-HBA). FIG. 2 shows the ¹ H-NMR spectrum of P(BHBA-co-2HEA-co-HBA). 1 is a graph showing thermogravimetry curves (TG curves) of PBHEA, P(BHEA-co-2EHA-co-HBA)1 and P(BHEA-co-2EHA-co-HBA)2. 1 is a graph showing TG curves of PBHBA, P(BHBA-co-HBA)1, P(BHBA-co-HBA)2 and P(BHBA-co-HBA)3. Fig. 3 is a graph showing TG curves of P(BHBA-co-2HEA-co-HBA) 1-7. 4 is a graph showing the results of a holding force test on SUS plates coated with P(BHBA-co-2HEA-co-HBA)2 and 5. FIG. 1 is a graph showing TG curves of thermal acid generators. 4 is a graph showing the results of a 180° peeling test performed on the pressure-sensitive adhesive tapes of Comparative Examples 1 and 2. FIG. 10 is a graph showing the results of a 180° peel test on the pressure-sensitive adhesive tapes of Comparative Example 3 and Examples 1 and 2. FIG. 10 is a graph showing the results of a 180° peeling test on the pressure-sensitive adhesive tapes of Comparative Example 4, Examples 5 and 6. FIG. 10 is a graph showing the results of a 180° peeling test performed on the pressure-sensitive adhesive tapes of Comparative Example 3, Examples 3 and 4. FIG. 10 is a graph showing the results of a 180° peeling test on the pressure-sensitive adhesive tapes of Comparative Example 4, Examples 7 and 8. FIG. It is the adhesive tape of Example 4 heated at 200° C. for 10 minutes. It is the adhesive tape of Example 7 heated at 200° C. for 5 minutes. 10 is a graph showing the results of a 180° peeling test performed on the pressure-sensitive adhesive tape of Example 3 after heat treatment at 150°C. 2 is a graph showing TG curves of PBHEMA (Comparative Example 5) and thermal acid generator-mixed polymer compositions of Examples 9-11. 2 is a graph showing the TG curves of PBHEMA (Comparative Example 5), the composition of Comparative Example 6, and the thermal acid generator mixed polymer compositions of Examples 9 and 12. FIG. 10 is a graph showing the weight change when the composition of Comparative Example 6 was subjected to isothermal heating. FIG. 10 is a graph showing the change in weight when the thermal acid generator-mixed polymer composition of Example 9 is subjected to isothermal heating. FIG. FIG. 10 is a graph showing the change in weight when the thermal acid generator-mixed polymer composition of Example 12 was subjected to isothermal heating. FIG. 2 is a graph showing Arrhenius plots of the composition of Comparative Example 6 and the thermal acid generator-mixed polymer compositions of Examples 9 and 12. FIG.

[Easily dismantling adhesive composition, thermally decomposable binder composition]
The easily dismantling adhesive composition or thermally decomposable binder composition of the present invention comprises a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at the end, and a thermal acid generator. At least one type of (meth)acrylic acid ester-based polymer containing (meth)acrylic acid ester-based monomer units having terminal tertiary alkoxycarbonyloxy groups contained in the easily dismantling adhesive composition and the heat-decomposable binder composition It may contain a plurality of types of polymers. Here, "(meth)acryl" in the present invention means acryl and/or methacryl.

<(Meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at the end>
In the present invention, "a (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at the terminal" means that the hydrogen atom of the carboxy group in (meth)acrylic acid having a substituent preferably at the α-position is at the terminal An ethylenically unsaturated monomer having a structure substituted with a hydrocarbon group having a tertiary alkoxycarbonyloxy group. Here, the hydrocarbon group can be an aliphatic hydrocarbon or an aromatic hydrocarbon. The aliphatic hydrocarbon has a straight chain of up to 12 carbon atoms (preferably 10 carbon atoms), a branched chain (if possible, specifically a case of 4 or more carbon atoms, hereinafter the same in the present specification) or a cyclic (When possible, specifically when the number of carbon atoms is 3 or more; hereinafter the same in the present specification) hydrocarbons (preferably saturated hydrocarbons) can be mentioned. Aromatic hydrocarbons include optionally substituted monocyclic or bicyclic aromatic hydrocarbons having up to 12 carbon atoms (preferably 10 carbon atoms).
The alkyls in the tertiary alkoxycarbonyloxy group are each independently straight or branched alkyls having 1 to 4 carbon atoms. Alkyl preferably has 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms, and more preferably 1 carbon atom.

The form of the (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at its end is not particularly limited, but for example the following formula (I):

(Wherein, R1 is selected from a hydrogen atom and an optionally substituted alkyl group having up to 4 carbon atoms, and R2, R3 and R4 are each independently linear chain or A is selected from branched alkyl groups, and A is selected from divalent groups derived from aliphatic hydrocarbons and aromatic hydrocarbons, which may have a substituent.

In the above formula (I), linear or branched alkyl groups having up to 4 carbon atoms include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec -butyl group, t-butyl group and the like.

In the above formula (I), A is not particularly limited as long as it is selected from divalent groups derived from aliphatic hydrocarbons and aromatic hydrocarbons, which may have a substituent. It is preferably selected from the group consisting of optionally substituted linear, branched or cyclic alkyl groups and aryl groups with up to 12 carbon atoms, and A is a substituent with up to 10 carbon atoms A is more preferably selected from the group consisting of linear, branched or cyclic alkyl groups and aryl groups, which may have a substituent of up to 8 carbon atoms , A is more preferably selected from the group consisting of linear or branched or cyclic alkyl groups and aryl groups; A is more preferably selected from the group consisting of alkyl groups and aryl groups of and A is from linear or branched or cyclic alkyl groups and aryl groups having up to 5 carbon atoms, which may have a substituent and A is selected from the group consisting of linear, branched or cyclic alkyl groups and aryl groups having up to 4 carbon atoms and optionally having substituents. is more preferably selected from saturated aliphatic hydrocarbons having up to 4 carbon atoms, more preferably saturated aliphatic hydrocarbons having 4 carbon atoms.

Divalent groups derived from aliphatic hydrocarbons include, for example, methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, nonamethylene group and decamethylene group. Linear alkylene group such as ethylidene group, propylene group, 1,2-butylene group, branched alkylene group such as 1,2-dimethylethylene group, cyclopropylene group, cyclobutylene group, cyclopentylene group, cyclohexane group Cycloalkylene groups such as a silene group, a cyclooctylene group, a cyclononylene group, and a cyclodecylene group are included.
Examples of divalent groups derived from aromatic hydrocarbons include phenylene groups, biphenylene groups, naphthalenediyl groups and the like.
Substituents are not particularly limited, but may be substituted with halogen atoms (especially F, Cl, Br, I), hydroxy groups, nitro groups, cyano groups, and halogen atoms having up to 4 carbon atoms. Linear or branched alkyl groups, alkoxy groups, carboxy groups and the like can be mentioned.

In the above formula (I), R1 is not particularly limited as long as it is selected from a hydrogen atom and an optionally substituted alkyl group having up to 4 carbon atoms; It is preferably an unsubstituted alkyl group, and R1 is a hydrogen atom, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, or sec-butyl group. or a t-butyl group, more preferably R1 is a hydrogen atom, a methyl group, an ethyl group, an n-propyl group or an i-propyl group, and R1 is a hydrogen atom, a methyl group or an ethyl group; more preferably, R1 is a hydrogen atom or a methyl group.

In the above formula (I), R2, R3 and R4 are not particularly limited as long as they are independently selected from linear or branched alkyl groups having up to 4 carbon atoms, but R2, R3 and R4 are the same or different. , methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group or t-butyl group, and R2, R3 and R4 are It is preferably selected from methyl group, ethyl group, n-propyl group and i-propyl group, more preferably R2, R3 and R4 are methyl group or ethyl group, and R2, R3 and R4 are methyl group. It is more preferable to have

Examples of the (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at the end represented by the above formula (I) include, for example, 2-(tert-butoxycarbonyloxy)ethyl acrylate (BHEA) or 4-(tert-butoxycarbonyloxy)butyl acrylate (BHBA) is preferred, and BHBA is more preferred.

A (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at its end, as represented by formula (I) above, includes, for example, a (meth)acrylic monomer having a hydroxy group at its end and a dialkyl dicarbonate. and are suspended in a solvent and reacted in the presence of a catalyst. Examples of the catalyst include 4-dimethylaminopyridine (DMAP), trialkylamine (alkyl has 1 to 4 carbon atoms, for example), and the like. Examples of solvents include toluene, chloroform, dichloromethane, acetone, methyl ethyl ketone and the like.

<(Meth)acrylic acid ester-based polymer>
The easily dismantling adhesive composition or thermally decomposable binder composition of the present invention contains a (meth)acrylic acid ester polymer containing a (meth)acrylic acid ester monomer unit having a tertiary alkoxycarbonyloxy group at its end. . The (meth)acrylic acid ester-based polymer of the present invention may be a polymer (homopolymer) of only a (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at its end. It may be copolymerized with a monomer other than the (meth)acrylic acid ester-based monomer having a terminal group. A copolymer may be a copolymer having a specific sequence pattern (eg, a block copolymer) or a copolymer having randomly arranged monomers.

Although the amount of units derived from a (meth)acrylic monomer having a tertiary alkoxycarbonyloxy group at the end contained in the copolymer is not particularly limited, for example, 1.0, 1.5, 2.0, 2.5, 3, 3.5, 4, 4.5, 5.0, 5.5, 6, 7, 7.5, 8, 9, 9.9, 10, 10.1, 10.5, 11, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62.5, 65, 67.5, 70, 71, 72.5 75, 77.5, 80, 85 , 90, 95, 98, 99, 99.9 mol%. The copolymer preferably contains 1 to 99 mol, more preferably 5 to 95 mol%, of units derived from a (meth)acrylic monomer having a tertiary alkoxycarbonyloxy group at the end, and 10 to More preferably 90 mol%, more preferably 15 to 90 mol%, more preferably 20 to 90 mol%, more preferably 25 to 90 mol%, 30 to 85 mol% It is more preferably contained, more preferably 30 to 80 mol%, more preferably 30 to 75 mol%, more preferably 30 to 70 mol%.

<Monomers other than (meth)acrylic acid ester-based monomers having a tertiary alkoxycarbonyloxy group at the end>
Examples of monomers other than (meth)acrylic acid ester-based monomers having a tertiary alkoxycarbonyloxy group at the end include vinyl-based monomers not having a tertiary alkoxycarbonyloxy group at the end, and 1,1-disubstituted ethylene type monomers. etc.
The amount of units derived from monomers other than (meth)acrylic acid ester-based monomers having terminal tertiary alkoxycarbonyloxy groups is not particularly limited, but is, for example, 1.0, 1.5, 2.0, 2.5, 3, 3.5, 4, 4.5. , 5.0, 5.5, 6, 7, 7.5, 8, 9, 9.9, 10, 10.1, 10.5, 11, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 17, 18, 19, 20 , 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45 , 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 62.5, 65, 67.5, 68, 70, 71, 72.5 75, 77.5, 80, The range can be any combination of upper and lower limits selected from the values 85, 90, 95, 98, 99, 99.9. It preferably contains 1 to 99 mol, more preferably 5 to 95 mol%, and 10 to 90 mol% of a unit derived from a (meth)acrylic monomer having a tertiary alkoxycarbonyloxy group at its end. more preferably 15 to 90 mol%, more preferably 20 to 90 mol%, more preferably 25 to 90 mol%, more preferably 30 to 85 mol% More preferably, it contains 30 to 80 mol %, more preferably 30 to 75 mol %, and more preferably 30 to 70 mol %.

<Vinyl Monomer Not Having a Tertiary Alkoxycarbonyloxy Group at the Terminal>
Examples of vinyl-based monomers having no terminal tertiary alkoxycarbonyloxy group (hereinafter also simply referred to as vinyl-based monomers) include (meth)acrylic-based monomers and styrene-based monomers.
(Meth)acrylic monomers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, and octyl (meth)acrylate. and alkyl esters of (meth)acrylic acid such as The alkyl group constituting the (meth)acrylic monomer may be linear or branched.
Styrenic monomers include, for example, styrene, α-methylstyrene, vinyltoluene, ethylstyrene, i-propylstyrene, t-butylstyrene, dimethylstyrene, bromostyrene, chlorostyrene and the like.
Among these, the vinyl-based monomer is preferably a (meth)acrylic monomer having an alkyl group having 2 to 12 carbon atoms, and a (meth)acrylic monomer having an alkyl group having 4 to 10 carbon atoms. is more preferred.

The vinyl-based monomer may contain a (meth)acrylic-based monomer having a hydroxyl group at its end. You may have one or more hydroxy groups. Examples of hydroxy-terminated (meth)acrylic monomers include hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and hydroxypentyl (meth)acrylate. Hydroxyalkyl esters of (meth)acrylic acid such as acrylate, hydroxyhexyl (meth)acrylate, and hydroxyoctyl (meth)acrylate can be mentioned. A hydroxyalkyl group constituting a (meth)acrylic monomer may be linear or branched.

<1,1-Disubstituted Ethylene Monomer Not Having a Tertiary Alkoxycarbonyloxy Group at the Terminal>
A 1,1-disubstituted ethylenic monomer not having a tertiary alkoxycarbonyl group at its terminal (hereinafter also simply referred to as a 1,1-disubstituted monomer) is a methacrylic monomer having a tertiary alkoxycarbonyl group at its terminal. It is not particularly limited as long as it can be copolymerized with.
1,1-Disubstituted monomers are, for example, the following formula (II):

(Wherein, R7 is selected from an ester group, a phenyl group, an alkyl group, a cycloalkyl group, an alkylcarbonyloxy group, an alkoxy group, a nitrile group and a halogen; selected from alkyl groups of numbers 1 to 8.)
A monomer having a structure represented by is mentioned.

Alkyl groups may be linear or branched, and may contain substituents.
When R7 is an ester group, it is preferred that the ester group is a primary alkyl ester. For example, when R8 is a methyl group, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, methacryl Tetradecyl acid, hexadecyl methacrylate, octadecyl methacrylate, i-butyl methacrylate, isoamyl methacrylate, cyclohexylmethyl methacrylate, 2-ethylhexyl methacrylate, benzyl methacrylate, phenethyl methacrylate, 2-hydroxyethyl methacrylate, methacrylic acid 2 -chloroethyl, 2,2-diaminoethyl methacrylate and the like.
Examples include α-methylstyrene when R7 is a phenyl group and R8 is a methyl group.
When R7 is an alkyl group and R8 is a methyl group, examples include isobutene, diisobutylene, oligoisobutylene and polyisobutylene.
When R7 is a cycloalkyl group and R8 is a methyl group, examples include α-methylvinylcyclohexane, α-methylvinylcyclopentane, limonene and the like.
Examples include isopropenyl acetate when R7 is an alkylcarbonyloxy group and R8 is a methyl group.
When R7 is an alkoxy group and R8 is a methyl group, α-methyl vinyl alkyl ether and the like can be mentioned.
When R7 is a nitrile group and R8 is a methyl group, examples include methacrylonitrile.
When R7 is an ester group and R8 is a substituted alkyl group, for example, itaconic acid ester can be mentioned. The itaconic acid ester has, for example, the following formula (III):

(Wherein, R9 is selected from an alkyl group having 1 to 6 carbon atoms, a phenyl group, and a cycloalkyl group, which may have a substituent.)
You may have a structure represented by Substituents are as described above.

The (meth)acrylic acid ester-based polymer according to the present invention is a monomer containing at least a (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at the end, in the presence of any polymerization initiator or catalyst described later. It can be obtained by polymerizing with The tertiary alkoxycarbonyloxy group of the (meth)acrylic acid ester-based monomer having a tertiary alkoxycarbonyloxy group at its end is decomposed by heating to generate gas.
For example, when the tertiary alkoxy group is a tert-butoxy group, carbon dioxide and isobutene are generated. Due to this property, for example, by using a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at the end as an adhesive, the adhesive is foamed by heating. (Meth)acrylic acid ester polymers containing (meth)acrylic acid ester monomer units having tertiary alkoxycarbonyloxy groups at their ends can reduce the adhesiveness of the adhesive due to the effects of area reduction, etc. A pressure-sensitive adhesive composition containing can be easily peeled off from an adherend after heating, that is, it becomes a pressure-sensitive adhesive composition having easy dismantling properties.

In this specification, easy dismantling means that the adhesive strength after heating is 50% or less of the adhesive strength of the adhesive before heating. Alternatively, the adhesive strength may be reduced to 50% or less of the adhesive strength before heating by heating at 100°C or higher for 40 minutes or less, or the adhesive strength before heating may be reduced by heating at 200°C or higher for 40 minutes or less. It may be 50% or less of the adhesive strength, or it may be 50% or less of the adhesive strength before heating by heating at 200°C or higher for 30 minutes or less, or 20% or less at 200°C or higher. The adhesive strength may be reduced to 50% or less of the adhesive strength before heating by heating within minutes, or the adhesive strength may be reduced to 50% or less of the adhesive strength before heating by heating at 200°C or higher for 10 minutes or less. The adhesive strength may be reduced to 30% or less of the adhesive strength before heating by heating at 200°C or higher for 20 minutes or less, or by heating at 200°C or higher for 20 minutes or less. It may be 20% or less of the adhesive strength of the previous adhesive, or it may be 10% or less of the adhesive strength before heating by heating at 200 ° C or higher for 20 minutes or less, The adhesive strength may be reduced to 10% or less of the adhesive strength before heating by heating at 200° C. or higher for 10 minutes or less. As used herein, the adherend refers to an object that provides a place to which an object to be fixed is fixed via an adhesive composition or an adhesive product containing an easily dismantleable adhesive composition described below.

As used herein, a thermally decomposable binder refers to a binder that can be decomposed and easily removed by firing at 150° C. or higher, for example. Alternatively, when the binder is heated from room temperature to 500° C. at a rate of temperature increase of 10° C./min, the weight of the binder after heating may be 20% or less of the weight of the binder before heating.
The (meth)acrylic acid ester-based polymer of the present invention has little carbon residue after heating, and the weight after heating by heating at 500° C. becomes 20% or less of the weight before heating. Therefore, the thermally decomposable binder composition of the present invention containing this (meth)acrylic acid ester-based polymer can be suitably used as a binder for ceramic sintered bodies, screen-printed articles, or laminated ceramic capacitors, for example.

The copolymer may have a crosslinked structure. A cross-linked structure may be formed, for example, by reacting hydroxy groups present in the copolymer with a cross-linking agent.
Examples of the cross-linking agent include compounds having two or more cross-linkable groups selected from isocyanate groups, glycidyl groups, aziridinyl groups, and the like. Among these, compounds having two or more isocyanate groups are preferred. Compounds having two or more isocyanate groups include aliphatic isocyanates such as hexamethylene diisocyanate (HDI), lysine diisocyanate, and lysine triisocyanate; Aromatic isocyanates such as cyclic isocyanate, diphenylmethane diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, p-phenylene diisocyanate, xylene diisocyanate, tetramethylxylylene diisocyanate and tolidine diisocyanate can be mentioned.
The cross-linking agent may cross-link the copolymer in advance before the adhesive is used, or may cross-link the copolymer by heating after being mixed with the copolymer at the time of use. The temperature and time for heating for cross-linking can be appropriately determined according to the cross-linking agent used.

<Physical properties of (meth)acrylate polymer>
The (meth)acrylate polymer of the present invention preferably exhibits a glass transition temperature (Tg) of -80 to 150°C. The range of polymer Tg is e.g. 36℃, -35℃, -34℃, -33℃, -30℃, -29℃, -28℃, -27℃, -26℃, -25℃, -24℃, -23℃, -22℃ , -21℃, -20℃, -19℃, -18℃, -17℃, -16℃, -15℃, -14℃, -13℃, -12℃, -11℃, -10℃, - 5℃, -3℃, -2℃, -1℃, 0℃, 1℃, 3℃, 5℃, 10℃, 11℃, 12℃, 13℃, 14℃, 15℃, 16℃, 17℃ , 18℃, 19℃, 20℃, 25℃, 30℃, 35℃, 40℃, 50℃, 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, 140℃ It can be a range represented by a combination of arbitrary upper and lower limits selected from values of °C or 150 °C.
Tg is preferably in the range of -50 to 100°C, more preferably in the range of -50 to 20°C, if the (meth)acrylic acid ester-based polymer of the present invention is used in an easily dismantling adhesive composition. more preferably in the range of -50 to 0°C, more preferably in the range of -50 to -10°C, more preferably in the range of -50 to -20°C . If the (meth)acrylate polymer of the present invention is used in a thermally decomposable binder composition, Tg is preferably in the range of -50 to 150°C, more preferably in the range of -20 to 150°C. is more preferred.

The polystyrene-equivalent number-average molecular weight (Mn) of the (meth)acrylic acid ester-based polymer of the present invention is not particularly limited, and can be appropriately adjusted according to the application. For example, if the (meth)acrylic acid ester-based polymer of the present invention is used in an easily dismantling adhesive composition, Mn is preferably 10,000 to 3,000,000, more preferably 20,000 to 2,000,000. A range of 20,000 to 1,000,000 may be used. If the (meth)acrylic acid ester-based polymer of the present invention is used in a thermally decomposable binder composition, Mn is preferably 5,000 to 2,000,000. Mn is preferably 5000 to 200000, more preferably 6000 to 180000, more preferably 7000 to 160000, more preferably 8000 to 130000, more preferably 9000 to 100000. .

Although the Mw/Mn (Mw is the weight average molecular weight) of the (meth)acrylic acid ester polymer of the present invention is not particularly limited, it preferably exhibits an Mw/Mn of 1 to 10. Mw/Mn is more preferably in the range of 1-5, more preferably in the range of 1-4.

The T _d5 of the (meth)acrylic acid ester-based polymer of the present invention is not particularly limited, but may have a T _d5 in the range of 150 to 250°C, and may have a T _d5 in the range of 160 to 240°C. and may have a T _d5 in the range of 180-230°C. Here, T _d5 refers to the temperature (thermal decomposition initiation temperature) at which the weight of the polymer decreases by 5% in the TG curve obtained by thermogravimetric measurement of the polymer.
_Tmax of the (meth)acrylic acid ester-based polymer of the present invention is not particularly limited, but may have _Tmax in the range of 150 to 250 ° C., T _max in the range of 170 to 250 ° C. and may have a T _max in the range of 200-250°C. Here, T _max refers to the temperature at which the thermal decomposition rate of the polymer is maximized in the TG curve obtained by thermogravimetric measurement of the polymer.

The (meth)acrylic acid ester-based polymer of the present invention includes, for example, a polymer obtained by homopolymerizing only 2-(tert-butoxycarbonyloxy)ethyl acrylate (BHEA), 4-(tert-butoxycarbonyloxy)butyl acrylate ( BHBA) only, copolymer of BHEA and 2-hydroxyethyl acrylate (HEA), copolymer of BHBA and 4-hydroxybutyl acrylate (HBA), BHEA and HBA A copolymer of BHBA and HEA A copolymer of BHEA, 2-ethylhexyl acrylate (2EHA) and HBA A copolymer of BHBA, 2EHA and HBA It may be a polymer, a polymer obtained by copolymerizing BHBA, 2EHA and HEA, or a polymer obtained by copolymerizing BHEA, 2EHA and HEA. Among these, it is preferably selected from a polymer obtained by homopolymerizing only BHBA, a polymer obtained by randomly copolymerizing BHBA and HBA, and a polymer obtained by copolymerizing BHBA, 2EHA and HBA. is more preferably a polymer obtained by copolymerizing These polymers may be polymerized regularly or randomly.

<Method for Producing (Meth)Acrylic Acid Ester-Based Polymer>
The (meth)acrylic ester-based polymer of the present invention includes, for example, a (meth)acrylic ester-based monomer having a tertiary alkoxycarbonyloxy group at its terminal and a vinyl-based monomer having no tertiary alkoxycarbonyloxy group at its terminal. and a 1,1-disubstituted ethylene type monomer having no terminal tertiary alkoxycarbonyloxy group are dissolved in a solvent and polymerized in the presence of a polymerization initiator or catalyst. Selection of a solvent, polymerization conditions (temperature, time, etc.) and the like can be appropriately set according to the conditions of the monomers and polymerization initiators to be used.

The polymerization initiator may be an initiator for radical polymerization (azo initiator, peroxide, redox initiator), an anionic polymerization initiator (alkyl lithium, Grignard compound), or a transition metal. It may be a catalyst for coordination polymerization using a catalyst. UV irradiation or radiation irradiation may be performed using a polymerization initiator or without using a polymerization initiator.
Examples of catalysts include azobisisobutyronitrile (AIBN), azobisdimethylvaleronitrile, benzoyl peroxide, lauryl peroxide and the like.

Examples of solvents include, but are not limited to, ethers (e.g., anisole, diethyl ether, tetrahydrofuran, etc.), alkanes (e.g., hexane, heptane, octane, cyclohexane, etc.), alcohols (methanol, ethanol, propanol, butanol, etc.). ), and carboxylic acid esters (ethyl acetate, butyl acetate, etc.).
As for the polymerization conditions, in the case of a thermal polymerization initiator, for example, the conditions include heating in the range of 0 to 120° C. for 0.5 to 48 hours.

<Thermal acid generator>
A thermal acid generator refers to a substance that generates an acid upon heating. Preferably the acid is a strong acid. Thermal acid generators also include those known as thermal cationic polymerization initiators. As used herein, the term “strong acid” refers to an acid having an acid dissociation constant (pKa) of 0 or less in water at 25°C.

The temperature at which the thermal acid generator generates acid is not particularly limited, but it may be a substance that generates acid by heating at a temperature of 80°C or higher, or a substance that generates acid by heating at a temperature of 90°C or higher. It may be a substance, or a substance that generates an acid by heating at a temperature of 100° C. or higher. Preferably, the thermal acid generator is a substance that generates a strong acid when heated at a temperature of 90°C or higher, and more preferably a substance that generates a strong acid when heated at a temperature of 100°C or higher. The temperature at which the thermal acid generator generates acid is preferably 250°C or lower, more preferably 240°C or lower, more preferably 230°C or lower, more preferably 220°C or lower, It is more preferably 210°C or lower, more preferably 200°C or lower. The temperature at which the thermal acid generator generates acid is preferably 90° C. or higher and 250° C. or lower, more preferably 100° C. or higher and 250° C. or lower, and more preferably 100° C. or higher and 220° C. or lower. More preferably, the temperature is 100°C or higher and 200°C or lower. The temperature at which the thermal acid generator generates acid may be the T _dx temperature of the thermal acid generator. The T _dx _of the thermal acid generator is not particularly limited _. It may have a T _dx in the range of 160°C. Here, T _dx refers to the temperature at which the weight of the thermal acid generator decreases by x% in the TG curve obtained by performing thermogravimetry on the thermal acid generator (for example, T _d5 (if any, refers to the temperature at which the weight of the thermal acid generator has decreased by 5%). Examples of T _dx include T _d5 , T _d10 , T _d15 , T _d20 , T _d25 , T _d30 , T _d35 , T _d40 , T _d45 , T _d50 and the like. Specifically, the T _d5 may have a T _d5 in the range of 60 to 200°C, may have a T d5 in the range of 70 to 180°C, and may have a T _d5 in the range of 90 to 160°C. It may have a T _d5 in the range.
The T _max of the thermal acid generator refers to the temperature at which the rate of weight loss in a specific period is maximized in the TG curve obtained by thermogravimetric measurement of the thermal acid generator.

Examples of thermal acid generators include ester compounds. Examples of ester compounds include inorganic esters such as sulfate esters, nitrate esters, carbonate esters and phosphate esters, and organic esters such as sulfonate esters and carboxylate esters. and more preferably an ester that generates a strong acid when heated at a temperature of 100° C. or higher. Examples of esters that generate a strong acid when heated to 100° C. or higher include sulfonate esters, sulfate esters, nitrate esters and the like, and sulfonate esters are preferred. A sulfonic acid ester can be synthesized, for example, by reacting an alcohol with sulfonic acid chloride in the presence of pyridine.

The sulfonic acid ester is, for example, the following formula (IV)

(Wherein, R5 is selected from the group consisting of optionally substituted linear, branched or cyclic alkyl groups and aryl groups with up to 18 carbon atoms, and R6 is selected from the group consisting of up to 10 carbon atoms , a linear or branched or cyclic alkyl group optionally having a substituent, wherein the substituent is a halogen atom, a hydroxy group, a nitro group, a cyano group, and up to 4 carbon atoms, selected from the group consisting of linear or branched alkyl groups, alkoxy groups and carboxy groups optionally substituted by halogen atoms)
and those having a structure represented by

In the above formula (IV), R5 is not particularly limited as long as it is selected from linear, branched or cyclic alkyl groups and aryl groups having up to 18 carbon atoms, which may have a substituent. optionally substituted, preferably selected from linear, branched or cyclic alkyl and aryl groups up to 15 carbon atoms, optionally substituted, preferably selected from straight-chain, branched or cyclic alkyl groups and aryl groups, selected from straight-chain, branched or cyclic alkyl groups and aryl groups having up to 10 carbon atoms and optionally having substituents; more preferably selected from the group consisting of optionally substituted aryl groups having up to 10 carbon atoms, and more preferably R5 is a benzyl group.

In the above formula (IV), R6 is not particularly limited as long as it is selected from the group consisting of linear, branched or cyclic alkyl groups having up to 10 carbon atoms and which may have a substituent. It is preferably selected from the group consisting of linear, branched or cyclic alkyl groups of 1 to 8, which may have a substituent, and more preferably R6 is an isopropyl group or a cyclohexyl group.

Examples of the sulfonic acid ester represented by the above formula (IV) include alkyl (o-, m-, p-)toluenesulfonate having 2 to 4 carbon atoms and cycloalkyl toluenesulfonate having 6 to 8 carbon atoms. Specific examples include cyclohexyl p-toluenesulfonate (CTS), propyl p-toluenesulfonate (PTS), isopropyl p-toluenesulfonate (ITS), and isopropyl methanesulfonate (IMS). Among these, CTS or ITS is preferable.

Thermal acid generators other than the ester compounds described above include, for example, aliphatic or aromatic sulfonium salts, aliphatic or aromatic iodonium salts, aliphatic or aromatic phosphonium salts, aliphatic or aromatic ammonium salts, and the like. . Among these, aliphatic or aromatic sulfonium salts are preferred, and aromatic sulfonium salts are more preferred. These thermal acid generators may be used alone or in combination of two or more.

The aforementioned salts are, for example, with the cations of aliphatic or aromatic sulfonium, aliphatic or aromatic iodonium, aliphatic or aromatic phosphonium, aliphatic or aromatic ammonium, BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , _and _anions selected from _AsF6- ^, _CF3SO3- ^, ( _CF3SO2 ) _2N- ^and _B ( _C6F5 ) _4- ^.

Examples of aromatic sulfonium salts include bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluorophosphate, bis(4-(diphenylsulfonio)phenyl)sulfide bishexafluoroantimonate, bis(4-(diphenyl sulfonio)phenyl)sulfide bistetrafluoroborate, bis(4-(diphenylsulfonio)phenyl)sulfide tetrakis(pentafluorophenyl)borate, diphenyl-4-(phenylthio)phenylsulfonium hexafluorophosphate, diphenyl-4-(phenylthio) ) phenylsulfonium hexafluoroantimonate, diphenyl-4-(phenylthio)phenylsulfonium tetrafluoroborate, diphenyl-4-(phenylthio)phenylsulfonium tetrakis(pentafluorophenyl)borate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoro antimonate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium tetrakis(pentafluorophenyl)borate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide bishexafluorophosphate, bis (4-(Di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide bishexafluoroantimonate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl) sulfide bis-tetrafluoroborate, bis(4-(di(4-(2-hydroxyethoxy))phenylsulfonio)phenyl)sulfide tetrakis(pentafluorophenyl)borate and the like.

Examples of aromatic iodonium salts include diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, diphenyliodonium tetrafluoroborate, diphenyliodonium tetrakis(pentafluorophenyl)borate, bis(dodecylphenyl)iodonium hexafluorophosphate, bis( Dodecylphenyl)iodonium hexafluoroantimonate, bis(dodecylphenyl)iodonium tetrafluoroborate, bis(dodecylphenyl)iodonium tetrakis(pentafluorophenyl)borate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoro Phosphate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium hexafluoroantimonate, 4-methylphenyl-4-(1-methylethyl)phenyliodonium tetrafluoroborate, 4-methylphenyl-4-(1 -methylethyl)phenyliodonium tetrakis(pentafluorophenyl)borate and the like.

Examples of aromatic diazonium salts include phenyldiazonium hexafluorophosphate, phenyldiazonium hexafluoroantimonate, phenyldiazonium tetrafluoroborate, and phenyldiazonium tetrakis(pentafluorophenyl)borate.

Aromatic ammonium salts include, for example, 1-benzyl-2-cyanopyridinium hexafluorophosphate, 1-benzyl-2-cyanopyridinium hexafluoroantimonate, 1-benzyl-2-cyanopyridinium tetrafluoroborate, 1-benzyl- 2-Cyanopyridinium tetrakis(pentafluorophenyl)borate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluorophosphate, 1-(naphthylmethyl)-2-cyanopyridinium hexafluoroantimonate, 1-(naphthylmethyl)- 2-cyanopyridinium tetrafluoroborate, 1-(naphthylmethyl)-2-cyanopyridinium tetrakis(pentafluorophenyl)borate and the like.

The content of the thermal acid generator in the heat-dismantling adhesive composition or the heat-decomposable binder composition is not particularly limited. The range of the content of the generator is, for example, the thermal acid generator is 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.49, 0.5 with respect to 100 parts by weight of the (meth)acrylic acid ester polymer. , 0.55, 0.60, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 0.99, 1.0, 1.1, 1.25, 1.5, 1.75, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.9, 2.7, , 3, 3.25, 3.5, 3.75, 4, 4.2, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.5, 6, 7, 7.5, 8, 9, 9.9, 10 parts by weight It can be a range represented by a combination of arbitrary upper and lower limits. The thermal acid generator is preferably contained in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 7 parts by weight, and 0.1 to 5 parts by weight with respect to 100 parts by weight of the (meth)acrylic acid ester polymer. is more preferably contained in

In the heat-dismantling adhesive composition or the heat-decomposable binder composition, if necessary, a (meth)acrylic acid ester containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at the end Additives other than the system polymer and the thermal acid generator may be contained. Examples of additives include organic solvents, tackifiers, plasticizers, antioxidants, ultraviolet absorbers, antioxidants, flame retardants, antifungal agents, silane coupling agents, fillers, colorants and the like. These additives may be contained in an amount of 40% by weight or less, preferably 35% by weight or less, based on the total weight of the heat-dismantling adhesive composition or the heat-decomposable binder composition. It is more preferably 25% by weight or less, more preferably 20% by weight or less, more preferably 15% by weight or less, and 10% by weight or less. is more preferable, and 5% by weight or less is more preferable.

Examples of organic solvents include aliphatic hydrocarbons such as hexane and heptane, esters such as methyl acetate, ethyl acetate, and propyl acetate, and aromatic hydrocarbons such as toluene, xylene, and ethylbenzene. An organic solvent may be used independently and may be used in combination of multiple types.

Examples of tackifiers include rosin-based resins, terpene-based resins, terpene-phenol-based resins, coumarone-indene-based resins, styrene-based resins, xylene-based resins, phenol-based resins, and petroleum resins. The tackifier may be used alone or in combination of multiple types.

Examples of plasticizers include polyols such as glycerin, diglycerin, triglycerin, ethylene glycol, propylene glycol and polyethylene glycol; Aromatic polycarboxylic acid esters such as polycarboxylic acid esters, terephthalic acid esters, isophthalic acid esters, phthalic acid esters, trimellitic acid esters, and benzoic acid esters, and polyesters. The plasticizer may be used alone or in combination of multiple types.

Examples of antioxidants include phenol-based antioxidants, amine-based antioxidants, lactone-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and the like. Antioxidants may be used alone or in combination of multiple types.

Examples of ultraviolet absorbers include benzotriazole-based compounds, benzophenone-based compounds, benzoate-based compounds, triazine-based compounds, and cyanoacrylate-based compounds. A single ultraviolet absorber may be used, or a plurality of types may be used in combination.

Anti-aging agents include, for example, aromatic secondary amine compounds, monophenol compounds, bisphenol compounds, polyphenol compounds, benzimidazole compounds, and phosphorous compounds. An anti-aging agent may be used independently and may be used in combination of multiple types.

Examples of flame retardants include phosphorus- and halogen-containing organic compounds, bromine- or chlorine-containing organic compounds, ammonium polyphosphate, aluminum hydroxide, antimony oxide, and other additive and reactive flame retardants. A flame retardant may be used independently and may be used in combination of multiple types.

Antifungal agents include arsenous acid, cuprous oxide, mercury oxide, organic sulfur compounds, phenol compounds, benzthiazole compounds, isothiazoline compounds, quaternary ammonium salt compounds, phosphonium salt compounds, and benzimidazole compounds. , pyridine-based compounds, and the like. The fungicides may be used alone or in combination of multiple types.

Examples of silane coupling agents include 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane and the like. A silane coupling agent may be used alone or in combination of multiple types. The amount of the silane coupling agent is preferably 10% by weight or less, more preferably 5% by weight or less, relative to the total weight of the heat-dismantling adhesive composition or heat-decomposable binder composition. .

Examples of fillers include silica, diatomaceous earth, alumina, zinc oxide, magnesium oxide, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, calcium silicate, carbon black, talc, mica, bentonite, activated clay, glass fiber, and glass. Beads, aluminum nitride, carbon fiber, and the like. The filler may be used alone or in combination of multiple types.

Examples of colorants include inorganic pigments such as carbon black, titanium oxide, zinc oxide, iron oxide and mica, and organic pigments such as coupling azo, condensed azo, anthraquinone, thioindigo, dioxazone and phthalocyanine pigments. A pigment etc. are mentioned. Colorants may be used alone or in combination of multiple types.

[Adhesive product containing heat-dismantling adhesive composition]
The present invention provides an adhesive product (hereinafter also simply referred to as an adhesive product) containing an easily dismantleable adhesive composition. The heat-dismantling adhesive composition is as described above.
One form of the adhesive product is composed of, for example, an adherend and an easily dismantleable adhesive layer formed so as to be in contact with the adherend. Further, as another form of the adhesive product, it is composed of a core material and two easily dismantleable adhesive layers formed so as to be in contact with both sides of the core material. The heat dismantling adhesive layer of these adhesive products contains a heat dismantling adhesive composition. The adhesive product of this embodiment functions as a substance that fixes a substance to be fixed to an adherend by the adhesive product (an object to be fixed) to the adherend.
The adherend is not particularly limited. Examples of adherends include metals such as Fe, Cu, Al, Ag, Au, Ti, Ni, W, Co, and Mg, metal plates and metal products made of alloys thereof, wooden plywood and workbench, and plastic plates. and plastic products. The fixed target is also not particularly limited. Examples thereof include metals such as iron, aluminum, copper, silver, and gold, or metal plates, metal products, and plastic products made of alloys of these metals.

The shape of the adhesive product is not particularly limited, but it can take an appropriate form, such as an adhesive tape or an adhesive sheet, depending on the application. The surface to be used of the heat-dismantling pressure-sensitive adhesive layer may be protected until it is used with a release-treated polyethylene terephthalate film, release paper, or the like.

The base material of the present embodiment refers to a planar object to which the heat-dismantling adhesive composition is applied. Base materials used for adhesive products include, for example, PET and polyimide films, carbon fibers, paper, woven fabrics, non-woven fabrics, and the like. A foil or plate made of a metal such as aluminum, copper, silver, or gold, or an alloy of these metals may be used. The thickness is also not particularly limited. The heat-dismantling pressure-sensitive adhesive layer may be formed not only on one side of the substrate but also on both sides. In this case, the base material is called the core material. By using the base material or the core material, the pressure-sensitive adhesive product can have strength, and workability during use can be improved.

The heat-dismantling pressure-sensitive adhesive layer can be formed, for example, by applying the heat-dismantling pressure-sensitive adhesive composition to a base material or a core material. The method of applying the heat-dismantling adhesive composition is not particularly limited. can. The thickness of the heat-dismantling adhesive layer is not particularly limited, but it is preferably in the range of 10 to 1000 μm, more preferably in the range of 15 to 750 μm, and more preferably in the range of 20 to 500 μm. .
The heat-dismantling adhesive layer preferably has an adhesive strength of 3N/25mm or more, more preferably 5N/25mm or more, and more preferably 7N/25mm or more. more preferably have an adhesive strength of 3N/25mm or more, more preferably have an adhesive strength of 9N/25mm or more, and have an adhesive strength of 10N/25mm or more It is more preferable to have Having an adhesive strength of 3N/25mm or more makes it an adhesive product with excellent fixation to adherends.

[Products containing a thermally decomposable binder composition]
The present invention provides an article of manufacture comprising the thermally decomposable binder composition. The thermally decomposable binder composition is as described above.
Examples of the form of the product containing the thermally decomposable binder composition include a ceramic firing binder product for producing a ceramic powder compact, a glass firing binder product for producing a glass powder compact, and a green sheet. Binder products for green sheet production for producing These products may use the thermally decomposable binder composition of the present invention as it is, or may contain the additives described above.
As the ceramic powder, those used for members constituting ceramic sintered bodies, screen-printed materials, or multilayer ceramic capacitors, which will be described later, can be used.
Examples of the glass powder include, but are not limited to, PbO- _B2O3 - _SiO2 _- based glass, PbO- _B2O3 _- based glass, PbO- _B2O3 _- _SiO2 - _Al2O3 _- based glass, ZnO Powder of _-B2O3 _-SiO2 _system glass, _Na2OB2O3 _- _SiO2 system glass, BaO-CaO _-SiO2 _system glass, PbO- _B2O3 _- _SiO2 -MgO system glass, etc. be done.

The product containing the thermally decomposable binder composition may be in a pasty state in which the thermally decomposable binder composition is suspended in a solvent. Examples of solvents include water and the above-described organic solvents. When suspending the thermally decomposable binder composition in a solvent, it may be dispersed in the solvent by adding an emulsifier. Examples of emulsifiers include, but are not limited to, nonionic surfactants such as polyethylene glycol monolaurate and polyethylene glycol monostearate.
The amount of the solvent for the thermally decomposable binder composition is not particularly limited, but can be, for example, 50 to 2000 parts by weight with respect to 100 parts by weight of the thermally decomposable binder composition. The amount of the emulsifier in the thermally decomposable binder composition is not particularly limited, but can be, for example, 1 to 200 parts by weight with respect to 100 parts by weight of the thermally decomposable binder composition.

The T _d5 of the easily dismantling adhesive composition or thermally decomposable binder composition of the present invention is not particularly limited, but may have a T _d5 in the range of 70 to 250°C. T _d5 may have a T _d5 in the range of 90-200°C; may have a T _d5 in the range of 100-190°C; It may have a T _d5 in the range. Here, T _d5 is the value of the easily dismantleable adhesive composition or the heat decomposable binder in the TG curve obtained by performing thermogravimetric measurement on the easily dismantleable adhesive composition or the heat decomposable binder. It refers to the temperature at which the weight is reduced by 5% (thermal decomposition initiation temperature).
_Tmax of the easily dismantling adhesive composition or thermally decomposable binder composition of the present invention is not particularly limited, but may have a _Tmax in the range of 130 to 250°C, and may be in the range of 140 to 240°C. and may have _{a T max} _in the range of 150-220°C. Here, T _max is the temperature of the easily dismantleable adhesive composition or the heat decomposable binder in the TG curve obtained by performing thermogravimetry on the easily dismantleable adhesive composition or the heat decomposable binder. It refers to the temperature at which the decomposition rate is maximum.

[Method for producing adhesive product containing heat-dismantling adhesive composition]
The present invention also provides a method of making a self-adhesive product comprising the heat-dismantle self-adhesive composition. Adhesive products can be produced by applying the easily dismantleable adhesive composition to a substrate or core material. The heat-dismantleable pressure-sensitive adhesive composition, the heat-dismantleable pressure-sensitive adhesive layer, the substrate, and the adhesive product including the heat-dismantleable pressure-sensitive adhesive composition are as described above.

[Method for manufacturing a product selected from ceramic sintered body, screen printed matter or multilayer ceramic capacitor]
Products that utilize the thermally decomposable binder composition of the present invention include, for example, ceramic sintered bodies, screen-printed articles, and laminated ceramic capacitors. The present invention provides a method of manufacturing an article selected from ceramic sintered bodies, screen prints or laminated ceramic capacitors using a thermally decomposable binder composition.
A ceramic sintered body, a screen-printed material, or a laminated ceramic capacitor is a mixture (hereinafter simply referred to as a mixture) obtained by mixing a member constituting a ceramic sintered body, a screen-printed material, or a laminated ceramic capacitor with the thermally decomposable binder composition of the present invention. is formed, the mixture is coated or molded, and the coated or molded mixture is heated to decompose the binder. The thermally decomposable binder composition used may be suspended in a solvent. Moreover, as the thermally decomposable binder composition, a product containing the aforementioned thermally decomposable binder composition may be used.

The members constituting the ceramic sintered body, the screen-printed article, or the laminated ceramic capacitor are not particularly limited, and those used for the production thereof can be used. Examples of such constituent materials include resins such as phenol and polyvinyl acetal, elemental metals such as Fe, Cu, Al, Ag, Au, Ti, Ni, W, Co, and Mg, alloys thereof, Al ₂ O ₃ , _SiO2 _, ZnO, _BaTiO3 , MgO, _TiO2 _, _CeO2 (cerium oxide), _Y2O3 (yttrium oxide), TiAl, _MoSi2 _, _{2MgO.2Al2O3.5SiO2} , _3Al2O3 _. _2SiO2 _, 2MgO.SiO2, _MgO.SiO2 _, Si3N4.AlN.Al2O3, _ZrO2.SiO2 , _Si3N4 , _AlN , BN, TiN, _CrN , _TiC _, _WC , _B4 C, SiC, _LaCrO3, etc. These may be used alone or in combination of two or more.

The member and the thermally decomposable binder composition described above can be mixed by any method. For example, mortars, ball mills, bead mills, hammer mills, pin mills, roller mills or jet mills can be used. Moreover, you may disperse|distribute and mix the member and thermally decomposable binder composition which were mentioned above to the organic solvent. As for the organic solvent, those mentioned above can be used. The component may be crushed prior to mixing the component with the thermally decomposable binder composition. A method for crushing the member is not particularly limited, and a ball mill, bead mill, hammer mill, pin mill, roller mill, jet mill, or the like can be used. The mixture may be powder or slurry.
The amount of thermally decomposable binder composition in the mixture is not particularly limited, but can be, for example, 1 to 30% by weight relative to the total weight of the mixture.

The method of applying the mixture is not particularly limited. For example, the coating method described above can be used. Molding (or lamination) may be carried out by repeating coating of a mixture (same or different mixture) on an object to which the mixture has been applied. Although the thickness of the coating film is not particularly limited, it can be in the range of 10 nm to 10 mm, for example. The pressure of the press may for example be selected from pressures in the range 50-2000 MPa.
The method of molding the mixture is not particularly limited, and can be appropriately selected depending on the application. For example, mechanical press molding, isostatic pressure (CIP) press molding, extrusion molding, injection molding and the like can be mentioned.

The heating conditions can be set as appropriate. The sintering temperature can be, for example, 100°C or higher and 2000°C or lower, preferably 120°C or higher and 1900°C or lower, preferably 150°C or higher and 1800°C or lower, and 170°C or higher and 1700°C or lower. preferably 200° C. or higher and 1600° C. or lower. In addition, the heating time is not particularly limited, but can be set, for example, from 5 minutes to 10 hours, can be in the range of 5 minutes to 7 hours, and can be in the range of 5 minutes to 5 hours. , can range from 5 minutes to 2 hours. By heating under such conditions, it is possible to obtain a ceramic sintered body, a screen-printed article, or a laminated ceramic capacitor with little residual binder after heating. Since the thermally decomposable binder composition of the present invention can be decomposed in a short heating time, the heat treatment can be completed in a short time, which is advantageous in terms of production cost and the like.

[Method for Separating Fixed Object Using Adhesive Product Containing Thermally Dismantleable Adhesive Composition]
The present invention provides a method for separating a fixed object using the heat-dismantling adhesive composition or adhesive product described above.
Separation of the object to be fixed is performed, for example, by fixing the object to be fixed to the adherend using the easily dismantleable adhesive composition or adhesive product, and then separating the easily dismantleable adhesive composition or the adhesive product from the composition. At a temperature (e.g., 100°C or higher, preferably 200°C or lower) at which the thermal acid generator in the substance or product generates acid (see <Thermal acid generator>) or higher for an appropriate time (e.g., 10 minutes or longer, (preferably 40 minutes or less) can be performed by heating. By this heating, the adhesive strength of the heat-dismantleable adhesive composition or adhesive product after heating can be reduced to 50% or less of the adhesive strength of the adhesive before heating. Heating may be performed on both the easily dismantleable adhesive composition or adhesive product and the fixing object to which it is fixed, or may be performed only on the easily dismantleable adhesive composition or adhesive product. When only the adhesive composition or adhesive product is treated, a method of pinpoint pressing a heating jig, a method of irradiating with energy rays (eg, ultraviolet rays, infrared rays, visible light, X-rays, etc.), and the like can be used. The heating temperature may be a temperature that does not damage the fixed object.

One embodiment of the present invention includes the use of a heat-dismantleable adhesive composition for the manufacture of a self-adhesive product comprising the heat-dismantleable adhesive composition. By forming a heat-dismantling pressure-sensitive adhesive layer on a substrate (or a core material) using the heat-dismantling pressure-sensitive adhesive composition, it is possible to produce an adhesive product containing the heat-dismantling pressure-sensitive adhesive composition. can. The details of the heat-dismantleable adhesive composition, the heat-dismantleable pressure-sensitive adhesive layer, the substrate, and the adhesive product including the heat-dismantleable pressure-sensitive adhesive composition are as described above.

One embodiment of the present invention is a thermally decomposable adhesive composition or a thermally decomposable binder composition containing a (meth)acrylic acid ester-based polymer containing 4-(tert-butoxycarbonyloxy)butyl acrylate monomer units. be. The (meth)acrylic acid ester-based polymer is as described above, except that it contains 4-(tert-butoxycarbonyloxy)butyl acrylate monomer as a monomer unit.

Specific embodiments are described below.

Item 1
A thermally decomposable adhesive composition or thermal decomposition comprising a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at its end, and a thermal acid generator binder composition.

Item 2
Item 2. The easily dismantling adhesive composition or thermally decomposable binder composition according to Item 1, wherein the thermal acid generator is an ester that decomposes at 90°C or higher to generate a strong acid.

Item 3
Item 3. The easily dismantling adhesive composition or thermally decomposable binder composition according to Item 2, wherein the ester is a sulfonic acid ester.

Item 4
The sulfonic acid ester has the following formula (I):

(In the formula,
R5 is selected from the group consisting of optionally substituted linear or branched or cyclic alkyl groups and aryl groups having up to 18 carbon atoms;
R6 is selected from the group consisting of linear, branched or cyclic alkyl groups having up to 10 carbon atoms and optionally having a substituent;
The substituents are halogen atoms, hydroxy groups, nitro groups, cyano groups, and groups consisting of linear or branched alkyl groups, alkoxy groups and carboxy groups having up to 4 carbon atoms and optionally substituted with halogen atoms. selected from)
Item 4. The easily dismantling adhesive composition or thermally decomposable binder composition according to item 3, represented by.

Item 5
R5 is selected from the group consisting of optionally substituted aryl groups having up to 10 carbon atoms,
wherein R6 is selected from the group consisting of linear, branched or cyclic alkyl groups having 2 to 8 carbon atoms and optionally having a substituent;
Item 5. The easily dismantling adhesive composition or thermally decomposable binder composition according to item 4.

Item 6
The (meth)acrylic acid ester-based monomer unit is represented by the following formula (II):

(In the formula,
R1 is selected from a hydrogen atom and an optionally substituted alkyl group having up to 4 carbon atoms,
R2, R3 and R4 are independently selected from linear or branched alkyl groups having up to 4 carbon atoms,
A is selected from divalent groups derived from aliphatic hydrocarbons and aromatic hydrocarbons, which may have a substituent)
Item 6. The easily dismantling adhesive composition or thermally decomposable binder composition according to any one of items 1 to 5, which is a (meth)acrylic ester monomer unit represented by.

Item 7
A is selected from the group consisting of optionally substituted linear or branched or cyclic alkyl groups and aryl groups having up to 12 carbon atoms;
The substituents are halogen atoms, hydroxy groups, nitro groups, cyano groups, and groups consisting of linear or branched alkyl groups, alkoxy groups and carboxy groups having up to 4 carbon atoms and optionally substituted with halogen atoms. selected from
Item 7. The easily dismantling adhesive composition or thermally decomposable binder composition according to item 6.

Item 8
Item 8. The easily dismantling adhesive composition or thermally decomposable binder composition according to

Item

6 or 7, wherein A is selected from saturated aliphatic hydrocarbons having up to 4 carbon atoms.

Item 9
Items 1 to 1, wherein the (meth)acrylic ester-based polymer is a copolymer containing vinyl-based monomer units and/or 1,1-disubstituted ethylene-based monomer units having no tertiary alkoxycarbonyloxy group at the end. 9. The heat-dismantling adhesive composition or heat-decomposable binder composition according to any one of 8.

Item 10
Item 10. The easily dismantling adhesive according to Item 9, wherein the copolymer contains 10 to 70 mol% of vinyl monomer units and/or 1,1-disubstituted ethylene monomer units having no terminal tertiary alkoxycarbonyloxy group. composition or thermally decomposable binder composition.

Item 11
11. The easily dismantling adhesive composition according to any one of Items 1 to 10, wherein the thermal acid generator is contained in an amount of 0.1 to 10 parts by weight with respect to 100 parts by weight of the (meth)acrylic acid ester polymer. material or thermally decomposable binder composition.

Item 12
12. A pressure-sensitive adhesive product having a pressure-sensitive adhesive layer containing the heat-dismantling pressure-sensitive adhesive composition according to any one of items 1 to 11.

Item 13
A product comprising the thermally decomposable binder composition according to any one of Items 1-11.

Item 14
A method for manufacturing a product selected from ceramic sintered bodies, screen prints or multilayer ceramic capacitors, comprising:
Coating or molding a mixture containing members constituting the product and the thermally decomposable binder composition according to any one of Items 1 to 11,
A method, characterized in that the coated or molded mixture is heated to decompose the binder.

Item 15
A method for dismantling a pair of members fixed via an adhesive layer,
A method comprising heating at least part of the adhesive layer, wherein the adhesive layer comprises the easily dismantleable adhesive composition according to any one of Items 1 to 11. .

Item 16
Item 16. The method according to item 14 or 15, wherein the heating is performed at a temperature at which the thermal acid generator in the easily dismantleable adhesive composition generates an acid or higher.

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples below, but the present invention is not limited to these.
In the following examples, 2-ethylhexyl acrylate (2EHA), 2-hydroxyethyl methacrylate (HEMA), and 4-hydroxybutyl acrylate (HBA) were purchased from Tokyo Chemical Industry Co., Ltd. and then distilled under reduced pressure. It was used after being purified by Di-tert-butyl dicarbonate (BOC) ₂ O manufactured by Tokyo Chemical Industry Co., Ltd. and 4-dimethylaminopyridine (DMAP) manufactured by Wako Pure Chemical Industries, Ltd. were used. Cyclohexyl p-toluenesulfonate (CTS) and isopropyl p-toluenesulfonate (ITS) manufactured by Tokyo Chemical Industry Co., Ltd. were used as they were. p-Toluenesulfonic acid (TsOH) manufactured by Tokyo Chemical Industry Co., Ltd. and heavy chloroform manufactured by Aldrich Co., Ltd. were used. 2,2'-Azobisisobutyronitrile (AIBN) used was obtained by dissolving Wako Pure Chemical Industries, Ltd. product in chloroform and then recrystallizing it by removing the solvent.

The heat treatment was performed using a vacuum constant temperature dryer VOS-300SD manufactured by Tokyo Rikakikai Co., Ltd. or AVO-200NB-CR manufactured by AS ONE Corporation.
In the following examples, thermal weight loss, glass transition temperature (Tg), ¹ H-NMR spectrum, molecular weight measurement, adhesive strength test, and heat treatment were measured using the following equipment under the following conditions.

(thermal weight loss)
The weight loss due to heating was measured using a differential thermal/thermogravimetric simultaneous measurement device DTG-80 manufactured by Shimadzu Corporation. Weight loss was measured. Alternatively, isothermal heating was carried out at a constant temperature, and changes in weight reduction with heating time were measured.

(Glass transition temperature (Tg))
Use a differential scanning calorimeter DSC250 manufactured by TA Instruments Japan Co., Ltd. to measure Tg, and measure by heating at 10°C/min under a nitrogen stream (flow rate 20-50 mL/min). The temperature at the tangent intersection point of the thermogravimetric curve obtained by was taken as Tg.

(NMR measurement)
¹ H-NMR spectra were measured using an FT-NMR spectrometer ECX400 (400 MHz) or ECS-400 (400 MHz) manufactured by JEOL Ltd., and deuterated chloroform was used as a solvent. Also, the composition ratio of each copolymer was calculated from the integral intensity of the ¹ H-NMR spectrum.

(molecular weight measurement)
Molecular weight measurements were performed by size exclusion chromatography (SEC) using polystyrene as a standard. JASCO Corporation's LC-2000Plus series was used as the high-performance liquid chromatography (HPLC) device, PU-2080-Plus as the pump, RI-2031-Plus as the differential refractive index detector, and DG- as the degasser. 2080-53 was used, and CS-300C manufactured by Chromatoscience was used as a constant temperature bath. As columns, TSKgel GMHHR-N and GMHHR-H manufactured by Tosoh Corporation were used. The temperature was maintained at 40° C., tetrahydrofuran (THF) was used as the developing solvent, and the flow rate was 0.8 mL/min.

(Holding force test)
A holding force test was conducted by preparing a stainless steel (SUS) plate coated with each polymer as follows.
A toluene solution was prepared by dissolving each polymer in toluene to a concentration of 10% by weight. This was dropped onto a stainless steel (SUS) plate (SUS430: 50 mm×150 mm, thickness 0.5 mm) that had been washed with acetone and dried, and was applied so that the application area was 10 mm×10 mm. After coating, the SUS plate was vacuum-dried for 2 hours to remove the solvent. Then, the coated surfaces of two SUS plates coated with the same polymer were superimposed, and a 2 kg hand roller was applied at a speed of 20 mm/s with an adhesive tape. The SUS plate was crimped by reciprocating twice in the length direction. Thirty minutes after crimping, the crimped SUS plate was vertically fixed with a clip. After fixing, a weight of a predetermined weight was attached to the lower SUS plate, and the time until it fell was measured. Each measurement condition was measured three times or more, and the average value was used as the measured value.

(Peeling test)
AUTOGRAPH AGS-1kNX manufactured by Shimadzu Corporation was used for the 180° peel test. The measurement was performed as follows according to JIS Z-0237 (2009).
A test sample (each synthesized polymer) was dissolved in toluene to prepare a 30% by weight polymer solution. This solution was applied to a PET film (width 350 mm, length 250 mm, thickness 50 μm) using a film applicator manufactured by Tester Sangyo Co., Ltd., and the thickness of the adhesive layer was reduced by vacuum drying to remove the solvent. A uniform adhesive tape was produced.
The adhesive tape was cut into strips with a width of 25 mm, and lightly attached to a stainless steel (SUS) plate (SUS430) that had been washed with toluene the day before and dried at normal temperature and pressure. A hand roller of 2 kg was reciprocated twice in the length direction of the adhesive tape at a speed of 20 mm/s to the attached adhesive tape, thereby crimping the adhesive tape.
30 minutes after crimping, using AUTOGRAPH AGS-1kNX, the force required to peel off the adhesive tape at an angle of 180° from the SUS plate at a pulling speed of 300mm/min (180°peel) (adhesive strength: N/25mm ) was measured.

(Synthesis of 2-(tert-butoxycarbonyloxy)butyl acrylate (BHEA))
4.64 g of 2-hydroxyethyl acrylate (HEA) and 8.73 g of (BOC) ₂ O were dissolved in toluene (10 mL). After dissolution, 4-dimethylaminopyridine (DMAP: 0.490 g) was further added and stirred at room temperature (about 25°C) for 24 hours to obtain BHEA. A reaction formula is shown below.

Chloroform (40 mL) was added to the obtained solution, and after performing an operation of washing with 40 mL of 5% HCl solution three times, the organic layer was dehydrated using anhydrous magnesium sulfate. After dehydration, magnesium sulfate was removed from the organic layer by gravity filtration. The filtrate was purified by column chromatography (developing solvent: chloroform/hexane=5/5, v/v, filler: alumina). The obtained purified product was subjected to distillation under reduced pressure and vacuum drying to obtain a colorless transparent liquid. The obtained liquid was subjected to ¹ H-NMR to confirm that it was BHEA. FIG. 1 shows the measured ¹ H-NMR spectrum of BHEA. The peak information of the spectrum is given below.
¹ H-NMR (400 MHz, CDCl ₃ ): δ6.40 (d, J = 17.5 Hz, 1H), 6.12 (dd, J = 17.5 Hz and 10.5 Hz, 1H), 5.83 (d, J = 10.5 Hz, 1H), 4.39-4.31 (m, 4H), 1.50 (s, 9H)

(Synthesis of 4-(tert-butoxycarbonyloxy)butyl acrylate (BHBA))
5.77 g of 4-hydroxybutyl acrylate (HBA) and 8.73 g of (BOC) ₂ O were dissolved in toluene (10 mL). After dissolution, 4-dimethylaminopyridine (DMAP: 0.489 g) was further added and stirred at room temperature (about 25°C) for 24 hours to obtain BHBA. A reaction formula is shown below.

Chloroform (40 mL) was added to the obtained solution, and after performing an operation of washing with 40 mL of 5% HCl solution three times, the organic layer was dehydrated using anhydrous magnesium sulfate. After dehydration, magnesium sulfate was removed from the organic layer by gravity filtration. The filtrate was purified by column chromatography (developing solvent: chloroform/hexane = 4/6, v/v, filler: alumina). The obtained purified product was subjected to distillation under reduced pressure and vacuum drying to obtain a colorless transparent liquid. The obtained liquid was subjected to ¹ H-NMR to confirm that it was BHBA. FIG. 2 shows the measured ¹ H-NMR spectrum of BHBA. The peak information of the spectrum is given below.
¹ H-NMR (400 MHz, CDCl ₃ ): δ6.43 (d, J = 17.5 Hz, 1H), 6.15 (dd, J = 17.5 Hz and 10.5 Hz, 1H), 5.86 (d, J = 10.5 Hz, 1H), 4.24-4.07 (m, 4H), 1.82-4.07 (m, 4H), 1.50 (s, 9H)

(Synthesis of 2-(tert-butoxycarbonyloxy)ethyl methacrylate (BHEMA))
9.80 g of 2-hydroxyethyl methacrylate (HEMA) and 3.98 g of (BOC) ₂ O were dissolved in toluene (10 mL). After dissolution, 0.490 g of DMAP was further added and stirred at room temperature (about 25°C) for 24 hours to obtain BHEMA. A reaction formula is shown below.

Chloroform (40 mL) was added to the obtained solution, and after performing an operation of washing with 40 mL of 1% HCl solution three times, the organic layer was dehydrated using anhydrous magnesium sulfate. After dehydration, magnesium sulfate was removed from the organic layer by gravity filtration. The filtrate was purified by column chromatography (developing solvent: chloroform/hexane = 3/7, v/v, filler: alumina). The obtained purified product was subjected to distillation under reduced pressure and vacuum drying to obtain a colorless transparent liquid. The obtained liquid was subjected to ¹ H-NMR to confirm that it was BHEMA. FIG. 3 shows the measured ¹ H-NMR spectrum of BHEMA. The peak information of the spectrum is given below.
¹ H-NMR (400 MHz, CDCl ₃ ): δ 6.12 (dq, J=17.4 Hz and 1.5 Hz, C=CH ₂ , 1H), 5.56 (dq, J=10.5 Hz and 1.5 Hz, C=CH ₂ , 1H), 4.32 (t, J=7.6 Hz, _CH2CH2 , 2H), 4.31 (t, J=7.6 Hz, _CH2CH2 _, 2H), 1.92 (dd, J ₌ 17.4 Hz and 10.5 Hz, CH _3C =C, 3H), and 1.47 (s, C( _CH3 ) ₃ , 9H).

(Synthesis of polymer of BHEA (PBHEA))
BHEA and AIBN were dissolved in anisole to form a homogeneous solution. This was placed in a polymerization tube, subjected to freeze-deaeration-thaw cycles three times, and then polymerized in a constant temperature bath at 60° C. for 3 hours. The freeze-pump-thaw cycle procedure is as follows. First, after freezing the contents of the polymerization tube with liquid nitrogen, the air inside the polymerization tube is depressurized and degassed using a vacuum pump, the cock is closed, the tube is thawed at room temperature, and then it is frozen again with liquid nitrogen and vacuum degassed. bottom. These operations were repeated three times. The polymerization reaction formula is shown below.

After the reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum dried at 60°C to obtain a PBHEA polymer. The resulting polymer was subjected to ¹ H-NMR to identify its structure. A ¹ H-NMR spectrum of the PBHEA polymer is shown in FIG.

(Synthesis of polymer of BHBA (PBHBA))
BHBA and AIBN were dissolved in anisole to form a homogeneous solution. This was placed in a polymerization tube, subjected to freeze-deaeration-thaw cycles three times, and then polymerized in a constant temperature bath at 60° C. for 3 hours. The polymerization reaction formula is shown below.

After the reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum dried at 60°C to obtain a PBHBA polymer. The resulting polymer was subjected to ¹ H-NMR to identify its structure. A ¹ H-NMR spectrum of the PBHBA polymer is shown in FIG.

(Synthesis of polymer of BHEMA (PBHEMA))
0.49 g of BHEMA and 7.3 mg of benzoyl peroxide (BPO) were dissolved in 3 mL of toluene to form a homogeneous solution. This was placed in a polymerization tube with a stopcock and subjected to three freeze-degas-thaw cycles. After that, polymerization was carried out at 80° C. for 24 hours in a constant temperature bath. The polymerization reaction formula is shown below.

After the reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum dried at 60°C to obtain a PBHEMA polymer. The resulting polymer was subjected to ¹ H-NMR to identify its structure. A ¹ H-NMR spectrum of the PBHEMA polymer is shown in FIG.

(Synthesis of random copolymers of BHBA and HBA)
BHBA, HBA and AIBN were dissolved in anisole at 60° C. at the molar ratios shown in Table 1 below to form a homogeneous solution. This was placed in a polymerization tube, subjected to freeze-deaeration-thaw cycles three times, and then polymerized in a constant temperature bath at 60° C. for 3 hours. The polymerization reaction formula is shown below.

After the polymerization reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum-dried at 60°C to obtain three types of P(BHBA-co-HBA). P(BHBA-co-HBA) was subjected to ¹ H-NMR to confirm the structure. ¹ H-NMR spectrum of P(BHBA-co-HBA) is shown in FIG. Using these copolymers, the number average molecular weight Mn and weight average molecular weight Mw were measured. Table 2 shows the results. Tables 1 and 2 also show results for PBHEA, PBHBA and PBHEMA.

(Synthesis of random copolymers of BHEA, 2EHA, and HBA)
BHEA, 2EHA, HBA and AIBN were dissolved in anisole at 60°C at the molar ratios shown in Table 3 below to form a homogeneous solution. This was placed in a polymerization tube, subjected to freeze-deaeration-thaw cycles three times, and then polymerized in a constant temperature bath at 60° C. for 3 hours. The polymerization reaction formula is shown below.

After the polymerization reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum dried at 60°C to obtain two types of P(BHEA-co-2EHA-co-HBA). P(BHEA-co-2EHA-co-HBA) was subjected to ¹ H-NMR to confirm the structure. ¹ H-NMR spectrum of P(BHEA-co-2EHA-co-HBA) is shown in FIG. Using these copolymers, the number average molecular weight Mn and weight average molecular weight Mw were measured. Table 4 shows the results.

(Synthesis of random copolymers of BHBA, 2HEA, and HBA)
BHBA, 2EHA, HBA and AIBN were dissolved in anisole at 60°C at the molar ratios shown in Table 5 below to form a homogeneous solution. This was placed in a polymerization tube, subjected to three freeze-degas-thaw cycles, and then polymerized in a constant temperature bath at 60°C for 3 hours. The polymerization reaction formula is shown below.

After the polymerization reaction, the reaction solution was dropped into a water/methanol mixed solution (1:9 v/v) for reprecipitation. This was decanted and vacuum-dried at 60°C to obtain 7 kinds of P(BHBA-co-2HEA-co-HBA) copolymers. P(BHBA-co-2HEA-co-HBA) was subjected to ¹ H-NMR to confirm its structure. ¹ H-NMR spectrum of P(BHBA-co-2HEA-co-HBA) is shown in FIG. Using these copolymers, the number average molecular weight Mn and weight average molecular weight Mw were measured. The results are shown in Table 5 below.

(thermal property evaluation)
The thermal properties of each polymer prepared were measured. The measurement results are shown in Table 6 below. The residual amount in the table is the residual amount of the polymer after the rapid weight loss observed at around 200° C. relative to the amount of the polymer before heating. The theoretical value is a value when it is assumed that all t-butoxycarbonyl groups (BOC groups) are decomposed and gaseous carbon dioxide and isobutene are eliminated from the polymer. Measured TG curves are shown in FIGS. 10A to 10C, respectively.

From Table 6, it can be seen that the BOC groups in the side chains of all polymers decomposed at around 200°C to generate isobutene and carbon dioxide.

(Holding force test)
A SUS plate coated with P(BHBA-co-2HEA-co-HBA)2 and P(BHBA-co-2HEA-co-HBA)5 or a SUS plate coated with the above copolymer is heated at 200°C for 40 minutes. Table 7 below and FIG. 11 show the results of a holding force test performed using the treated SUS plate. T _f in Table 7 indicates the holding time of the weight, and L ₆₀ indicates the displacement of the SUS plate 60 minutes after the start of the test. From Table 7 and FIG. 11, it can be seen that the holding force increases with heating.

(Thermal property evaluation of thermal acid generator)
Thermal properties of two thermal acid generators, isopropyl p-toluenesulfonate (ITS) and cyclohexyl p-toluenesulfonate (CTS), were measured. The measurement results are shown in Table 8 below and FIG. The residual amount in the table is the residual amount of the thermal acid generator after rapid weight reduction observed around 100 to 200° C. relative to the thermal acid generator before heating. The theoretical value is a value when it is assumed that all the ester sites of the thermal acid generator are decomposed. In the table, the T _max of the decomposition in the first stage is the temperature at which the weight loss rate is maximized in the interval of 100 ° C to 180 ° C, and the T _max of the decomposition in the second stage is 190 ° C to 300 ° C. °C is the temperature at which the rate of weight loss is maximum.
Table 8 and FIG. 12 show that ITS and CTS show weight loss due to decomposition of the ester site and are particularly suitable as thermal acid generators.

Preparation of (P(BHBA-co-2HEA-co-HBA) copolymer-thermal acid generator mixed polymer composition co-2HEA-co-HBA)5 and either isopropyl p-toluenesulfonate (ITS) or cyclohexyl p-toluenesulfonate (CTS) as a thermal acid generator was mixed to obtain eight types of thermal acid generator mixed polymers. Compositions (Examples 1 to 8) were prepared, and the correspondence of the 8 types of thermal acid generator mixed polymer compositions is shown in Table 9. The values of ITS and CTS in the table indicate the amount of thermal acid generator added. It is a weight ratio to the copolymer.

(180° peel test)
A 180° peeling test was performed on the prepared 8 types of thermal acid generator-mixed polymer compositions. In the 180° peel test, in addition to eight adhesive compositions, P(BHEA-co-2EHA-co-HBA) 1 (Comparative Example 1), P(BHEA-co-2EHA-co-HBA) 2 ( Comparative Example 2), P(BHBA-co-2HEA-co-HBA)2 (Comparative Example 3) or P(BHBA-co-2HEA-co-HBA)5 (Comparative Example 4) alone is also compared. used as The composition of each example or comparative example is shown together with the one used as it is and the one heated before the test. The results of the 180° peel test are shown below in Tables 10 and 11, respectively. Table 10 shows the results of Comparative Examples 1 to 4 and Examples 1, 2, 5 and 6, and Table 11 shows the results of Comparative Examples 1, 2 and Examples 3, 4, 7 and 8, respectively. These results are also shown in FIGS. 13A-13E, respectively.

From Tables 10 and 11, the P(BHBA-co-2HEA-co-HBA) copolymer-thermal acid generator mixed polymer composition showed adhesive strength even in a short time of about 5 to 10 minutes when heated at 200°C. It can be seen that it drops significantly. FIG. 14A shows the adhesive tape of Example 4 heated for 10 minutes, and FIG. 14B shows the adhesive tape of Example 7 heated for 5 minutes. From FIGS. 14A and 14B, traces of foaming of the copolymer can be seen on the adhesive tape after heating. From these results, it was shown that the addition of the thermal acid generator generated acid by heating and accelerated the decomposition of the BOC group. -It was shown that the thermal acid generator-mixed polymer composition can be easily peeled off by heating for a short time.

Table 12 and FIG. 15 show the results of heat treatment of the adhesive tape of Example 3 at 150°C. Table 12 shows that the film can be easily peeled off even by heating at 150°C.

Preparation of PBHEMA-thermal acid generator mixed polymer compositions Four types of thermal acid generator mixed polymer compositions (Examples 9 to 12) were prepared by mixing prepared PBHEMA with ITS or CTS as a thermal acid generator. . Table 13 shows the correspondence of the four thermal acid generator mixed polymer compositions. The CTS numbers in the table are weight ratios for the copolymer to which the thermal acid generator was added.

(Measurement of thermal properties of thermal acid generator-mixed polymer compositions of Examples 9-12)
The thermal properties of the prepared thermal acid generator-mixed polymer compositions of Examples 9 to 11 were measured. The measurement results are shown in Table 14 and FIG. 16 below. For comparison, the thermal properties of PBHEMA (Comparative Example 5) alone were also measured.

From Table 14 and FIG. 16, it can be seen that the decomposition temperature of PBHEMA can be lowered by combining with a thermal acid generator. Also, the value of T _d5 decreased with increasing concentration of thermal acid generator. From this, it is possible to control the decomposition temperature of a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at the end by adjusting the concentration of the thermal acid generator. It has been shown.

Comparison between a PBHEMA and acid composition and a PBHEMA-thermal acid generator mixed polymer composition A composition with 1.0 wt% of a simple acid (p-toluenesulfonic acid: TsOH) added instead of a thermal acid generator It was produced (Comparative Example 6) and the thermal properties were measured. For comparison, PBHEMA (Comparative Example 5) and the thermal acid generator-mixed polymer compositions of Examples 9 and 12 were also measured in the same manner. The measurement results are shown in Table 15 and FIG. 17 below.

From Table 15 and FIG. 17, the composition of Comparative Example 6 to which p-toluenesulfonic acid was added had a low decomposition temperature, and even if the amount added was 1 wt%, the thermal acid generator mixed polymer of Example 11 with 5 wt% of ITS was added. It can be seen that the decomposition temperature is close to that of the composition.

Measurement of Thermal Properties by Isothermal Heating The composition of Comparative Example 6 and the thermal acid generator-mixed polymer compositions of Examples 9 and 12 were subjected to isothermal heating to measure changes in weight loss with heating time. The results are shown in FIGS. 18A-18C, respectively. From Figures 18A to 18C, it can be seen that the composition of Comparative Example 6 to which p-toluenesulfonic acid was added loses weight even at a low temperature such as 60°C. In contrast, the thermal acid generator-mixed polymer compositions of Examples 9 and 12 show almost no weight loss even after heating at 100° C. for 6 hours. A reaction rate constant was calculated from a first-order plot of the measured decomposition reaction rate. The reaction rate constants obtained are shown in Table 16, and the Arrhenius plots are shown in FIG.

From Table 16, the decomposition reaction proceeds even at a low temperature of 60°C in the composition of Comparative Example 6, whereas the thermal acid generator-mixed polymer compositions of Examples 9 and 12 undergo decomposition reaction at a temperature of 100°C or less. It can be seen that it does not progress and has high thermal stability. It is also found that the decomposition reaction of the thermal acid generator-mixed polymer compositions of Examples 9 and 12 does not proceed at a temperature of 100°C or lower, but the decomposition reaction proceeds rapidly at a high temperature of 150°C. This is because the composition of Comparative Example 6 uses a simple acid, so decomposition proceeds from the time of mixing, whereas the use of a thermal acid generator allows decomposition of the BOC group of the polymer when mixed with the polymer. It is believed that this is because the protective group of the thermal acid generator is released by heating without causing a reaction, generating acid and decomposing the BOC group in the polymer.

From the above examples, it can be seen that by combining a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at the end with a thermal acid generator, stable at room temperature It was shown that a heat-dismantling pressure-sensitive adhesive composition or a heat-decomposable binder composition having high properties and capable of being easily decomposed by heating can be obtained.

Claims

A thermally decomposable adhesive composition or thermal decomposition comprising a (meth)acrylic acid ester-based polymer containing a (meth)acrylic acid ester-based monomer unit having a tertiary alkoxycarbonyloxy group at its end, and a thermal acid generator binder composition.
2. The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 1, wherein the thermal acid generator is an ester that decomposes at 90[deg.] C. or higher to generate a strong acid.
3. The thermally decomposable adhesive composition or thermally decomposable binder composition according to claim 2, wherein said ester is a sulfonic acid ester.
The sulfonic acid ester has the following formula (I):

(In the formula,
R5 is selected from the group consisting of optionally substituted linear or branched or cyclic alkyl groups and aryl groups having up to 18 carbon atoms;
R6 is selected from the group consisting of linear, branched or cyclic alkyl groups having up to 10 carbon atoms and optionally having a substituent;
The substituents are halogen atoms, hydroxy groups, nitro groups, cyano groups, and groups consisting of linear or branched alkyl groups, alkoxy groups and carboxy groups having up to 4 carbon atoms and optionally substituted with halogen atoms. selected from)
The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 3, represented by
R5 is selected from the group consisting of optionally substituted aryl groups having up to 10 carbon atoms,
wherein R6 is selected from the group consisting of linear, branched or cyclic alkyl groups having 2 to 8 carbon atoms and optionally having a substituent;
The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 4.
The (meth)acrylic acid ester-based monomer unit is represented by the following formula (II):

(In the formula,
R1 is selected from a hydrogen atom and an optionally substituted alkyl group having up to 4 carbon atoms,
R2, R3 and R4 are independently selected from linear or branched alkyl groups having up to 4 carbon atoms,
A is selected from divalent groups derived from aliphatic hydrocarbons and aromatic hydrocarbons, which may have a substituent)
3. The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 1 or 2, which is a (meth)acrylic ester monomer unit represented by:
A is selected from the group consisting of optionally substituted linear or branched or cyclic alkyl groups and aryl groups having up to 12 carbon atoms;
The substituents are halogen atoms, hydroxy groups, nitro groups, cyano groups, and groups consisting of linear or branched alkyl groups, alkoxy groups and carboxy groups having up to 4 carbon atoms and optionally substituted with halogen atoms. selected from
The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 6.
The easily dismantling adhesive composition or thermally decomposable binder composition according to claim 6, wherein A is selected from saturated aliphatic hydrocarbons having up to 4 carbon atoms.
2. The (meth)acrylic acid ester-based polymer is a copolymer containing vinyl-based monomer units and/or 1,1-disubstituted ethylene-based monomer units having no terminal tertiary alkoxycarbonyloxy group. 6. The easily dismantling adhesive composition or thermally decomposable binder composition according to any one of 1 to 5.
10. The easily dismantleable according to claim 9, wherein the copolymer contains 10 to 70 mol% of vinyl-based monomer units and/or 1,1-disubstituted ethylene-type monomer units having no terminal tertiary alkoxycarbonyloxy group. Adhesive composition or thermally decomposable binder composition.
The easily dismantling adhesive according to any one of claims 1 to 5, wherein the thermal acid generator is contained in an amount of 0.1 to 10 parts by weight with respect to 100 parts by weight of the (meth)acrylic acid ester polymer. composition or thermally decomposable binder composition.
A pressure-sensitive adhesive product having a pressure-sensitive adhesive layer containing the heat-dismantling pressure-sensitive adhesive composition according to any one of claims 1 to 5.
A product containing the thermally decomposable binder composition according to any one of claims 1 to 5.
A method for manufacturing a product selected from ceramic sintered bodies, screen prints or multilayer ceramic capacitors, comprising:
Coating or molding a mixture containing members constituting the product and the thermally decomposable binder composition according to any one of claims 1 to 5,
A method, characterized in that the coated or molded mixture is heated to decompose the binder.