JP2013067744A - Adhesive agent and method for disassembling adhered structure - Google Patents

Abstract

An adhesive having high adhesive strength during operation and high reliability such as heat resistance and moisture resistance, which can be easily disassembled by external stimulus during disassembly.
It has a cyclic structure composed of C atoms and one or more atoms of N, O, and S atoms, and even when added, the reliability of the adhesive is not impaired at the time of use. An adhesive containing a cyclic compound that is large and easily decomposes by moderate heating. At the time of disassembly, the adhesive layer becomes brittle due to decomposition of the cyclic compound, and the adhesive structure can be disassembled.
[Selection] Figure 1

Description

  The present invention relates to the field of adhesives capable of easily disassembling devices and device parts related to recycling and rework for the purpose of constructing a production supply system in a recycling society.

  In recent years, interest in environmental issues such as global warming and resource depletion has increased, and various efforts have been made to build a recycling-oriented society in the state or enterprise from the viewpoint of global environmental conservation. In the field of adhesives, in order to meet the social needs for effective use of resources in addition to high functionality, development of dismantling adhesives aimed at recycling used parts and regenerating defective parts as part of reducing environmental impact Has been done. As the disassembling means, an adhesive that imparts dismantling properties with heat is generally used. This is because the thermal dismantling method requires no capital investment, can use existing equipment, and can be easily implemented without requiring complicated means. For example, by adding a thermally expandable filler in the adhesive and heating it to the dismantling temperature, the adhesive layer expands with the filler, and after heating, the adhesive layer shrinks and cracks when it is cooled. This is a hot melt adhesive (Patent Document 2) in which the adhesive layer is softened and melted by heat and disassembled (Patent Document 1). Further, as another dismantling means using heat, an adhesive having an organic melting agent or an inorganic exothermic agent added has been reported. These are techniques in which the adhesive layer is disassembled by heating to a temperature at which it melts or generates heat, and chemical change of the added substance. As organic melting agents, acetamidophenol, biphenylcarboxylic acid, guanidine nitrate, and magnesium-based powders and nitro compounds as inorganic heating agents have been reported. (Patent Document 3 and Patent Document 4)

JP 2003-171648 A JP 2004-977 A JP 2009-114276 JP 2001-212900 A

  Structural adhesives with guaranteed heat resistance and chemical resistance have high mechanical strength, and it is difficult to reduce the adhesive strength to be able to be manually disassembled using the current heat disassembly technique.

  For example, a thermosetting adhesive imparted with a disintegrating property by adding a thermally expandable filler has an adhesive strength of several MPa after heating at 300 ° C., and does not reach an adhesive strength that can be manually disassembled. Generally, when a thermally expandable filler is heated to 300 ° C., the outer skin deteriorates, and the encapsulated hydrocarbons are lost, so that the expansion effect of the filler cannot be exhibited.

  In addition, since the hot melt adhesive softens with an increase in temperature, for example, when the temperature is instantaneously increased due to a malfunction, the adhesive strength is instantaneously decreased, and reliability is not accompanied. Moreover, it is necessary to dismantle at a high temperature, and there is a problem in workability.

  On the other hand, when an organic melting agent is used, the carboxylic acid or amino group in the molecular structure as a melting agent reacts with the adhesive component during curing and is incorporated into the structure. The role as an agent cannot be sufficiently exhibited, and there is a possibility that the adhesive strength cannot be lowered. In addition, the effect of the inorganic heat generating agent depends on the installation environment, absorbs moisture in a high humidity environment, and easily ignites in a dry environment, and the usage environment is limited.

  An object of the present invention is to provide an adhesion technique that exhibits high reliability in a wide range of operating environments such as humidity and temperature, and has good workability during disassembly and can be reduced to an adhesive strength that can be easily manually disassembled. .

  The present invention has an adhesive property with excellent heat resistance, maintains the same reliability as the initial stage regardless of the operating environment, and can be reduced to an adhesive strength that can be manually disassembled during disassembly. It is related to.

Specific examples of the demountable adhesive according to the present invention are shown below.
<Details for solving problems>
The present invention provides an adhesive composition that is highly reliable and can be disassembled using an external stimulus. Furthermore, the present invention provides an adhesive composition that can be disassembled with heat that does not incur equipment costs and can be easily disassembled.

  As a result of intensive studies to solve this problem, a conclusion has been reached that can be solved by adding the following compounds.

  In order to solve the problem, a compound that is stable at the temperature at which the adhesive cures and in the humidity and temperature range in the operating environment, further decomposes rapidly at the decomposition temperature, and some of the decomposition components, preferably all It is possible to achieve both reliability and decomposability when the decomposition component is a compound that vaporizes.

  A compound having this characteristic is a cyclic compound having a large steric strain in which the number of atoms constituting the ring is 3 or more and 7 or less, consisting of at least one of N, O, and S atoms in addition to C atoms. Was found to be effective. For example, the H—C—H bond angle of ethyleneimine, which is a cyclic compound, is about 60 °, which is smaller than the bond angle 109 ° of linear hydrocarbons. Therefore, the steric strain is large and the compound is expected to have high reactivity. On the other hand, the reactivity shifts to a high temperature side by substituting with a large functional group such as a stable phenyl group, alkyl group, or halogen atom instead of H bonded to carbon of the main skeleton of the cyclic compound. Can do. For this reason, the ethyleneimine derivative to which a bulky substituent is bonded is stable in the environment at the time of operation, and when heated at a decomposition temperature shifted to a high temperature side, a part of the ethyleneimine derivative is decomposed and a decomposition component becomes a gas.

  Among the cyclic compounds, the isocyanuric acid or isocyanuric acid derivative represented by the structure of FIG. 1 has high heat resistance, and does not react with the adhesive component in an operating environment and is stable without interaction. However, an atom-derived gas that decomposes at 200 ° C. or more to form a cyclic compound structure is generated. For this reason, the disassembly effect can be exhibited by adding the cyclic compound of FIG. 1 to the adhesive component. It is clear that the adhesive layer to which the cyclic compound is added does not have a decomposition component of the cyclic compound and is hollowed by heating to the decomposition temperature or higher. For this reason, the adhesive layer becomes brittle. The adhesive strength after heating is reduced to 1/50 to 1/100 of the adhesive strength after curing (initial), and can be easily reduced to an adhesive strength that can be manually disassembled.

  In addition, the same effect is exhibited even in a 3- to 10-membered ring containing any one or more of N, O, and S elements having large steric strain shown in FIG. 2 and derivatives thereof. More preferably, 3 or more and 7 or less member ring is preferable. There are no compounds below the 3-membered ring, and if it is 8 or more members, it remains in the adhesive layer as a decomposed product even if it is decomposed by heating, and the adhesive strength is not sufficiently lowered.

  The ring contains at least one S atom, N atom, and O atom as R1, and further has an R2 group bonded thereto (when R1 is O, there is no R2). A plurality of R1 that are not C atoms may be contained in the ring.

  Furthermore, examples of the cyclic compound having the same effect include unsaturated acetylene oxide, acetylene sulfide, pyrrole, furan, thiophene, azatropylidene, oxycycloheptatriene, thiotropyridene, and compound derivatives thereof.

  The concentration of these additives is preferably added in the range of 0.1% to 30%. If it is less than 0.1%, the desired disassembly effect cannot be obtained, and if it is 30% or more, the initial adhesive strength may be reduced, and the adhesive properties may change. The effects of the cyclic compounds described above are different and are selected depending on the type of adhesive component to be added.

  When the additive is solid, the particle size also depends on the dismantling effect. The particle size of the additive is desirably within 0.1 to 100 um. More preferably, it is 1 um or more and 50 um or less. Although it is difficult to pulverize or mold organic materials to 1 um or less, there is a possibility of damage to the human body during handling due to the influence of dust. On the other hand, when the particle size is 50 μm or more, the adhesive film thickness is 50 μm or more, which causes a decrease in adhesive strength. Furthermore, the larger the particle size, the more easily the additive settles during the curing, and it hardens in a state of being agglomerated at the adhesive interface, resulting in a decrease in adhesive strength. For this reason, it is preferable that it is less than 1-50um.

  In this way, in the adhesive component, the main skeleton is composed of at least one atom among C atoms and N, O, and S atoms, and a cyclic compound having 3 to 7 membered rings is in a suitable range. By adding in the concentration and the particle size, the cyclic compound is stable without change during operation, and the reliability can be maintained. Further, at the time of disassembly, by heating at a temperature equal to or higher than the decomposition temperature of the cyclic compound, it is possible to reduce the adhesive strength to a value that allows quick disassembly immediately after heating. The first and second problems can be solved by adding the cyclic compound to the adhesive.

  The adhesive component can be used without selecting the type as long as it does not have reactivity with the cyclic organic compound according to the present invention.

  The resin component serving as the main skeleton preferably uses a resin having the same structure as the resin component serving as the main skeleton in order to maintain the current adhesive properties. The resin and monomer that are the main skeleton are appropriately selected according to the purpose, such as an epoxy resin and an acrylic monomer.

  First, the epoxy adhesive will be described. As the epoxy resin, bisphenol A and bisphenol F skeleton are preferable. When cured from a low molecule, the crosslink density increases, so the adhesive strength is high and the heat resistance is excellent. Phenol novolac and biphenyl skeleton epoxy resins are also preferable as the main component of the adhesive because of their high crosslink density and high heat resistance. However, since these epoxy resins have a high elastic modulus and the adhesive strength may be lowered, the adhesive strength can be increased by adding a plasticizer or the like, or in combination with the bisphenol A skeleton or bisphenol F skeleton epoxy resin. The desired adhesive strength can be obtained without lowering.

  Also, for the purpose of imparting flexibility, polyglycidylamine triglycidylaminophenol, tetraglycidylmetaxylenediamine, dimer acid diglycidyl ester, bisphenol A diglycidyl ether dimer acid addition to bisphenol A skeleton epoxy resin Or dioctyl phthalate, nonylphenol or the like may be appropriately mixed.

  The curing agent for the epoxy resin is appropriately selected from the following compounds.

  The curing agent is mainly selected from amine, acid anhydride, and phenol.

  The amine curing agent is selected from among aliphatic polyamines, alicyclic polyamines, aromatic polyamines, and latent curing agents. Since aliphatic polyamines can be cured at room temperature without heating and have excellent adhesion, triethylenetetramine, hexamethylenediamine, tetraethylenediamine, trimethylhexamethylenediamine and the like are preferable. Moreover, xylenediamine and isophoronediamine are preferable as the alicyclic polyamine, and are appropriately selected. The aromatic amine is preferably diaminodiphenylmethane, m-phenylenediamine, or toluenediamine. Also, a polyamide amine in which an amino group capable of reacting with an epoxy group is left as a reaction product of an amine and a dimer acid, or dicyandiamide or adipic acid hydrazide is preferably used as a latent curing agent depending on the purpose based on adhesive properties and curing properties. It is selected appropriately.

  As acid anhydride curing agents, 3.4 methyl-1.2.3.6.-tetrahydrophthalic anhydride, 3or4 methyl-hexahydrophthalic anhydride, and todecenyl succinic anhydride are liquid and easy to handle. Further, in the solid form, trimellitic anhydride, pyromellitic anhydride, and benzophenonetetracarboxylic anhydride are preferably selected according to the purpose.

  The phenolic curing agent is appropriately selected from tris (dimethylaminomethyl) phenol, phenol novolac and the like.

  The compounding amount of the amine-based, acid anhydride-based, or phenol-based curing agent is determined by determining the epoxy equivalent of the epoxy resin or empirically.

  Catalysts for accelerating the reaction between the epoxy resin and the curing agent are, as imidazole series, 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2-phenyl- It is appropriately selected from 4.5-dihydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo [1,2-a] benzimidazole, DCMU, 2,4,6-tris (dimethylaminomethyl) phenol (DMP30), etc. The Moreover, imidazole type | system | group can also be used as a hardening | curing agent.

Further, a filler is necessary to increase the strength of the adhesive layer.
The filler is appropriately selected from silica, alumina, calcium carbonate, aluminum hydroxide and the like.

  Further, a silane coupling agent or the like may be used for improving adhesion.

  Next, an acrylic adhesive composition will be described. Acryl resin includes alkyl (meth) acrylate, dicyclopenteroxyalkyl methacrylate, bisphenol A diacrylate, ethylene oxide adduct dimethacrylate of bisphenol A, nonylphenol EO adduct acrylate, 2-hydroxy-3-phenoxypropyl acrylate, hydroxy Ethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, ethoxylated phenyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, monohydroxyethyl acrylate phthalate, benzyl methacrylate, phenoxyethyl methacrylate, 2-methacryloyloxyethyl It is selected from 2-hydroxypropyl phthalate, tripropylene glycol diacrylate, and the like.

  Further, the reaction initiator is selected from the following substances. Azobisisobutyrylnitrile, benzoyl peroxide, benzophenone, benzylmethyl ketal, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2- Methyl-1-phenyl-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1.

  Further, as a reaction initiator having good photosensitivity on the long wavelength side, a mixture of bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide and 1-hydroxy-cyclohexyl-phenyl-ketone Alternatively, a mixture of bis (2,6-dimethyoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide and 1-hydroxy-cyclohexyl-phenyl-ketone is appropriately selected and used.

  The addition amount of the reaction initiator is preferably 0.1 to 7 parts by weight, more preferably 0.5 to 3 parts by weight with respect to 100 parts by weight of the acrylic resin. When it is 0.5 or less, the effect as an initiator cannot be obtained, and when it is 3 parts by weight or more, an abnormal reaction easily occurs. For this reason, the suitable range of a reaction initiator is 0.5-3 weight part.

  Moreover, since the wavelength at the time of curing varies depending on the absorption characteristics of the reaction initiator, it is determined by the type of the selected reaction initiator. It is preferable to perform light irradiation at an absorption wavelength of 180 to 500 nm. The reaction initiator is most often a compound having a maximum absorption in the vicinity of 280 to 350 nm. However, the reaction initiator is not limited to the above range and may be irradiated on the short wavelength and long wavelength sides depending on the optical characteristics of the reaction initiator. It is appropriately selected depending on the absorption characteristics of the reaction initiator used.

  The light irradiation is preferably performed using a mercury lamp or laser light. It is appropriately selected depending on the curing characteristics.

  The problem is solved by adding a cyclic compound having a large steric strain imparting disassembly to the above-described epoxy-based and acrylic-based adhesives. According to the present invention, reliability in an operating environment can be maintained without deteriorating adhesive properties. Further, at the time of disassembly, the bonded structure can be disassembled quickly by heating at the disassembly temperature.

  According to the present invention, it is possible to provide an adhesion technique that exhibits high reliability and has good workability during disassembly and can be reduced to an adhesive strength that can be easily dismantled.

It is an example of the structure of isocyanuric acid. This is an example of a three-membered ring compound having C as the main skeleton and containing at least one atom of N, O, and S. It is an example of a 4-membered ring compound having C as the main skeleton and containing at least one N, O, or S atom. It is an example of a 5-membered ring compound having C as the main skeleton and containing at least one atom of N, O, and S. It is an example of a 6-membered ring compound having C as the main skeleton and containing at least one N, O, or S atom. This is an example of a 7-membered ring compound having C as the main skeleton and containing at least one or more N, O, and S atoms. Effect 1 test results carried out in Examples 1 to 11 and Comparative Examples 1 to 5. The verification result 2 test result of the effect implemented in Example 1- Example 11 and Comparative Example 1- Comparative Example 5. FIG. It is the molecular structure of isocyanuric acid concerning an Example. It is the molecular structure of the dichloro isocyanuric acid concerning an Example. It is the molecular structure of the trishydroxyethyl isocyanate concerning an Example. 1 is a molecular structure of methyl 1- (trisphenylmethyl) -2-aziridinecarboxylate according to an example. It is the molecular structure of thiazolidine-3,4-dicarboxylate according to the example. It is the molecular structure of DL-3-amino-2-oxohexamethyleneimine salt concerning an Example. It is the molecular structure of p-acetaminophenol concerning a comparative example. It is the molecular structure of the guanidine nitrate concerning a comparative example.

  Below, the disassembly adhesive composition of Examples 1 to 11 and Comparative Examples 1 to 5 according to the present invention was prepared, and adhesive structures of the adhesive composition were prepared. The produced bonded structure was subjected to an adhesive strength test and reliability evaluation to verify the effect.

  <Preparation Method of Adhesive Composition of Example with Dismantling>

The components shown below were weighed in a predetermined container, and kneaded under a kneading condition of 200 rpm, 100 KPa, 1.5 min using a self-revolving vacuum defoaming mixer to prepare an adhesive composition.
50 parts by weight of bisphenol A skeleton epoxy resin (trade name JER-828), 30 parts by weight of bisphenol F skeleton epoxy resin (trade name JER-828), 10 parts by weight of dicyandiamide (trade name DICY7 manufactured by Mitsubishi Chemical Corporation), silica (Product name: FB-50S, manufactured by Denki Kagaku Kogyo Co., Ltd.) 8 parts by weight, 3- (3,4-dichlorophenyl) -1,2-dimethylurea (DCMU) (manufactured by Hodogaya Chemical Co., Ltd.), 3 wt. Department.

  10 parts by weight of isocyanuric acid (manufactured by Nissan Chemical Industries, Ltd., shown in FIG. 5 (a)) is added to 100 parts by weight of the adhesive composition described above, and again, a self-revolving vacuum defoaming mixer-ARV -310 By Thinky, an adhesive composition containing a compound that imparts disassembly was prepared by kneading under the same conditions as described above.

  After adding 1 part by weight of dichloroisocyanuric acid (shown in Fig. (B), manufactured by Nissan Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition described in Example 1, the same as the kneading conditions described in Example 1. The adhesive composition containing the compound which knead | mixes on conditions and provides dismantling property was adjusted.

  After adding 10 parts by weight of trishydroxyethyl isocyanate (produced by Nissan Chemical Industries, Ltd., shown in FIG. 5 (c)) to 100 parts by weight of the adhesive composition described in Example 1, the kneading conditions described in Example 1 The adhesive composition containing the compound which knead | mixes on the same conditions and provides dismantling property was adjusted.

  10 parts by weight of methyl 1- (trisphenylmethyl) -2-aziridinecarboxylate (shown in FIG. 5 (d), manufactured by Tokyo Chemical Industry Co., Ltd.) is added to 100 parts by weight of the adhesive composition described in Example 1. After that, kneading was performed under the same conditions as those described in Example 1 to prepare an adhesive composition containing a compound that imparts dismantling properties.

  After adding 20 parts by weight of thiazolidine-3,4-dicarboxylate-3-ethyl (shown in FIG. 5 (e), manufactured by Tokyo Chemical Industry Co., Ltd.) to 100 parts by weight of the adhesive composition described in Example 1. The adhesive composition containing the compound which knead | mixes on the same conditions as the kneading | mixing conditions of Example 1 and provides dismantling property was adjusted.

  10 parts by weight of DL-3-amino-2-oxohexamethyleneimine salt (shown in FIG. 5 (f), manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 100 parts by weight of the adhesive composition described in Example 1. Then, the adhesive composition containing the compound which knead | mixes on the same conditions as the kneading | mixing conditions of Example 1 and provides dismantling property was adjusted.

  The following components were weighed into a predetermined container and kneaded under the same conditions as in Example 1 to prepare an adhesive composition. Bisphenol A skeleton epoxy resin (trade name: JER-828) 100 parts by weight, 3or4 methylhexahydrophthalic anhydride (trade name: HN-5500, manufactured by Hitachi Chemical Co., Ltd.), 85 parts by weight, tertiary amine salt (trade name: Amicure -MY-24) 3 parts by weight, silica (trade name: FB-50S, manufactured by Denki Kagaku Kogyo Co., Ltd.) 8 parts by weight.

  After adding 10 parts by weight of isocyanuric acid (shown in FIG. 5 (a), manufactured by Nissan Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition, the mixture was kneaded under the same conditions as those described in Example 1. An adhesive composition containing a compound that imparts dismantling properties was prepared.

  After adding 1 part by weight of dichloroisocyanuric acid (shown in FIG. 5 (b), manufactured by Nissan Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition described in Example 7, the kneading conditions described in Example 1 and The adhesive composition containing the compound which knead | mixes on the same conditions and provides dismantling property was adjusted.

  The following components were weighed into a predetermined container and kneaded under the same conditions as in Example 1 to prepare an adhesive composition. Bisphenol A skeleton epoxy resin (trade name JER-828) 100 parts by weight, polyamine amide (trade name Versamide 140 made by Henkel Co., Ltd.) 60 parts by weight, 2-ethyl-4-methylimidazole (trade name 2E4MZ Shikoku Kasei Kogyo ( 3 parts by weight (made by Co., Ltd.) and 8 parts by weight of silica (trade name: FB-50S, made by Denki Kagaku Kogyo Co., Ltd.).

  After adding 10 parts by weight of dichloroisocyanuric acid (shown in FIG. 5 (a), manufactured by Nissan Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition, kneading is performed under the same conditions as those described in Example 1. Then, an adhesive composition containing a compound that imparts disassembly was prepared.

  The following components were weighed into a predetermined container and kneaded under the same conditions as in Example 1 to prepare an adhesive composition. Bisphenol A skeleton epoxy resin Product name JER-828 100 parts by weight, polyvinyl phenol Product name Marcalinker S-1 Maruzen Petrochemical Co., Ltd., 50 parts by weight, Tris (dimethylaminomethyl) phenol (Nacalai Disc Co., Ltd.) 5 parts by weight, silica (trade name FB-50S, manufactured by Denki Kagaku Kogyo Co., Ltd.) 8 parts by weight.

  After adding 10 parts by weight of dichloroisocyanuric acid (shown in FIG. 5 (b). Nissan Chemical Industries, Ltd.) to 100 parts by weight of the described adhesive composition, the same conditions as the kneading conditions described in Example 1 The adhesive composition containing the compound which knead | mixed and gave dismantling property was adjusted.

  Dichloroisocyanuric acid (shown in FIG. 5 (b), manufactured by Nissan Chemical Industries, Ltd.) with respect to 100 parts by weight of an acrylic one-component useless UV curing adhesive (trade name 3065E, manufactured by Three Bond Co., Ltd.) After adding 10 parts by weight, an adhesive composition containing a compound imparting dismantling properties was prepared by kneading under the same conditions as those described in Example 1.

<Adhesive composition preparation method of comparative example to which disassembly was imparted>
[Comparative Example 1]
After adding 20 parts by weight of magnesium oxide (MgO) (manufactured by Wako Pure Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition described in Example 1, the mixture was kneaded under the same conditions as those described in Example 1. An adhesive composition containing a compound that imparts dismantling properties was prepared.
[Comparative Example 2]
After adding 20 parts by weight of p-acetaminophenol (shown in FIG. 6 (a), manufactured by Wako Pure Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition described in Example 1, The adhesive composition containing the compound which knead | mixes on the same conditions as kneading | mixing conditions and provides dismantling property was adjusted.
[Comparative Example 3]
After adding 20 parts by weight of guanidine nitrate (shown in FIG. 6B, manufactured by Wako Pure Chemical Industries, Ltd.) to 100 parts by weight of the adhesive composition described in Example 1, the kneading conditions described in Example 1 were The adhesive composition containing the compound which knead | mixes on the same conditions and provides dismantling property was adjusted.
[Comparative Example 4]
After adding 20 parts by weight of thermally expandable filler (trade name F-260D) and 20 parts by weight of Matsumoto Yushi Seiyaku Co., Ltd. to 100 parts by weight of the adhesive composition described in Example 1, kneading as described in Example 1 The adhesive composition containing the compound which knead | mixes on the conditions same as conditions and provides dismantling property was adjusted.
[Comparative Example 5]
Example 1 After adding 20 parts by weight of guanidine nitrate Wako Pure Chemical Industries, Ltd. to 100 parts by weight of an acrylic one-component useless UV curable adhesive (trade name 3065E, manufactured by Three Bond Co., Ltd.), Example 1 The adhesive composition containing the compound which knead | mixes on the same conditions as the kneading | mixing conditions of description and provides dismantling property was adjusted.

<Method for producing bonded structure>
In the adhesive compositions having the dismantling properties of Examples 1 to 11 and Comparative Examples 1 to 5, adhesion structures using the following members were produced.
First member: silicon steel plate,
Shape 10mm × 50mm × 0.5mm
Second member: Fe-Ni alloy with 10um Ni electroless plating
Shape 20mm × 20mm × 0.5mm
As the bonding method, an adhesive was applied to the tip of the silicon steel plate so as to have a bonding area of 10 mm square and bonded to the Fe—Ni alloy plate. After sandwiching the adhesive part with clips from both sides and leaving it to stand for 60 minutes at room temperature, both the examples and comparative examples are cured under the curing conditions shown in Tables 1 and 2, and after cooling (only in the case of thermal curing), the clips are removed, An adhesive structure was produced.

<Verification of effect 1>
The adhesive structures of Examples 1 to 11 and Comparative Examples 1 to 5 were tested for adhesive strength (shear) after curing (initial) and adhesive strength (shear) after heating at 300 ° C. Table 3 shows the test results of the examples, and Table 4 shows the test results of the comparative examples. The results of Tables 3 and 4 are graphed and shown in FIG. The numerical value of the adhesive strength represents an average value of n = 10.

In Examples 1 to 11, the adhesive strength after heating was reduced to about 1/100 after curing (initial), and an adhesive strength capable of manual disassembly was obtained. On the other hand, although the adhesive strength after 300 degreeC heating of the comparative example 3 and the comparative example 5 reduced to 1 MPa or less, it was not able to be achieved by the adhesive strength which can be disassembled manually. In the other comparative examples, the adhesive strength after curing (initial) remained at a level of 2 to 3 MPa or more and about 1/10, and it was not possible to obtain an adhesive strength that could be manually disassembled.
<Verification of effect 2>
In the bonded structures of Examples 1 to 11 and Comparative Examples 1 to 5, reliability evaluation (temperature shock) was performed with -20 (15 min) to 60 (15 min) ° C. as one cycle. Table 5 shows the evaluation results of Examples in which tests of the adhesive strength (shear) after curing (initial) and the adhesive strength (shear) after 500 cycles were performed, and Table 6 shows the evaluation results of Comparative Examples. The results of Tables 5 and 6 are graphed and shown in FIG. The numerical value of the adhesive strength represents an average value of n = 10.

As a result of reliability evaluation in Examples 1 to 11, the adhesive strength after 500 cycles hardly changed with respect to the adhesive strength after curing (initial). For this reason, the reliability of the adhesive composition of the present invention has been maintained. On the other hand, in the comparative example, the adhesive strength after the reliability evaluation of the comparative example 3 and the comparative example 5 was reduced to about 1/2 with respect to the epoxy type and the acrylic type, after curing (initial), and the reliability was lowered. .
In addition, although Comparative Example 1 Comparative Example 2 Comparative Example 4 had good reliability, from the result of <Effect Verification 1>, the dismantling effect was not obtained.

  <Effect verification 1> In the results of <Effect verification 2>, the bonded structure produced using the adhesive composition of the present invention has good reliability in the operating environment, and at the time of disassembly, it exceeds the decomposition temperature. It has been proved that it can be easily dismantled by heating. The present invention is a highly reliable structural adhesive, and can be easily disassembled by heating at a decomposition temperature or higher. By applying the adhesive composition of the present invention, recycle and reworkability are improved.

Claims (10)

An adhesive component that reacts when cured, and an additive component
The adhesive is characterized in that the additive component is a compound including a cyclic structure composed of at least one element of N, O, and S atoms and a C atom. In claim 1,
The cyclic structure of the additive component is composed of 3 to 10 atoms, and one or two cyclic structures are contained in one molecule of the additive component. In claim 1 or claim 2,
The additive composition is an isocyanuric acid or a derivative of isocyanuric acid. In any one of Claim 1 thru | or 3,
The adhesive is characterized in that the additive component is non-reactive with respect to the adhesive component. In any one of Claims 1 thru | or 4,
The adhesive composition, wherein the cyclic compound is decomposed at a decomposition temperature or a melting point or higher, and a decomposition product of the cyclic compound is vaporized. In any one of Claims 1 to 5,
The amount of the additive component in the adhesive is 0.1 to 30 parts by weight with respect to 100 parts by weight of the adhesive component. In any one of Claims 1 thru | or 6,
The adhesive characterized in that the particle size of the cyclic compound is 0.1 um or more and 100 um or less. In any one of Claims 1 thru | or 7,
The adhesive component is an epoxy or acrylic adhesive, and is cured by heat or light. In the dismantling method of the adhesive structure bonded with an adhesive,
The adhesive comprises an adhesive component that is polymerized upon curing, and an additive component that is a compound including a cyclic structure composed of at least one element of N, O, and S atoms and C atoms,
Heating the adhesive;
A method for disassembling an adhesive structure, comprising: applying a force to the heated adhesive to break the adhesive. In claim 9,
The heating temperature is 100 ° C. or higher and 350 ° C. or lower.

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