JP2003096423A - Thermosetting adhesive composition and pressure- sensitive adhesive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermosetting adhesive composition that has well- balanced properties between the pre-adhesion for tape positioning before the thermosetting and the adhesion and has heat resistance after the thermosetting. SOLUTION: In the adhesive composition comprises 100 pts.wt. of an epoxy resin, 1-200 pts.wt. of a thermoplastic resin and 1-80 pts.wt. of a latent hardening agent, 1-100 pts.wt. of an epoxy-modified elastomer and 1-200 pts.wt. of a high heat resistant epoxy resin are used.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a curable pressure-sensitive adhesive composition containing an epoxy resin and a thermoplastic resin as main components and a magnetic substance-containing pressure-sensitive adhesive sheet using the same.

[0002]

2. Description of the Related Art In recent years, with the demand for smaller, thinner and lighter electric products such as mobile phones and mobile devices, semiconductor components, magnetic parts, mounted parts such as substrates, etc. used have been made smaller, thinner and highly integrated. There is a strong demand for realization.

These small mounted components are individually cut out by pasting a single substrate on which a large number of the mounted components have been prepared in advance to an adhesive sheet. As this adhesive sheet, a thermosetting adhesive / adhesive or a thermosetting adhesive / adhesive sheet having various functions and characteristics is used.

Such a thermosetting adhesive / adhesive sheet is an adhesive material which can be stuck at room temperature like an ordinary adhesive tape and is made into an adhesive by being cured by heating after being adhered to exhibit excellent adhesive performance. is there. This thermosetting adhesive / adhesive sheet is adopted because it does not need to be applied to an adherend before adhesion unlike ordinary liquid adhesives, and can be re-attached so that positioning is easy and workability and workability are improved. This is because it is easy to use.

[0005]

This thermosetting adhesive / adhesive includes, for example, an epoxy resin and a thermoplastic resin, but is non-adhesive and has a function as an adhesive / adhesive. There were problems such as not having. Here, even if it is attempted to give tackiness to this thermosetting pressure-sensitive adhesive, it is difficult to balance the tackiness and the adhesiveness. For example, if the tackiness is to be improved, the adhesion after curing And heat resistance are sacrificed (for example, Japanese Patent Laid-Open No. 7-1385).
No. 50). Further, when it is attached to a mounted component, there are problems that leakage of magnetic flux occurs and magnetic characteristics are reduced.

In view of the above, the present invention is a thermosetting method which exhibits repositionable tackiness for positioning before curing, excellent adhesiveness and heat resistance after curing, and exerts a well-balanced performance as a tacky adhesive. An object is to provide a pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet. Another object of the present invention is to provide a thermosetting pressure-sensitive adhesive composition and a pressure-sensitive adhesive sheet that do not cause magnetic flux leakage and do not reduce magnetic properties.

[0007]

Means for Solving the Problems As a result of earnest research, the inventors of the present invention have made a thermosetting adhesive / adhesive composition contain an epoxy-modified elastomer and a highly heat-resistant epoxy resin, thereby imparting tackiness. At the same time, they have found that the adhesiveness and heat resistance after curing are prevented from being lowered, and the balance between the adhesiveness before curing and the adhesiveness after curing is improved, and the present invention has been completed.
Further, it was found that the inclusion of a soft magnetic material in the product of the present invention did not cause leakage of magnetic flux and did not reduce the magnetic characteristics, and completed another invention.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION That is, the thermosetting pressure-sensitive adhesive composition of the present invention comprises 100 parts by weight of an epoxy resin, 1 to 200 parts by weight of a thermoplastic resin, and 1 to 80 parts by weight of a latent curing agent. 1 to 100 parts by weight of an epoxy-modified elastomer and 1 to 100 parts of a high heat-resistant epoxy resin in a thermosetting adhesive composition
The thermosetting adhesive composition contains 200 parts by weight.

In another invention, the soft magnetic material is added to the thermosetting adhesive / adhesive composition of the present invention in an amount of 20 based on the total solid content.
-60 volume% is compounded.

In another invention, the thermosetting adhesive / adhesive sheet is obtained by applying these thermosetting adhesive / adhesive compositions onto a release film and drying the composition.

The reason why the epoxy-modified elastomer is used in the thermosetting pressure-sensitive adhesive composition of the present invention is to impart tackiness to the entire composition. If the compounding ratio of this epoxy-modified elastomer is too small, the tackiness will not be exhibited, and if it is too large, the adhesiveness and heat resistance will be reduced.
It is preferably 0 part by weight, more preferably 20 to
60 parts by weight.

The epoxy-modified elastomer can be appropriately selected as long as it exhibits the above-mentioned function, and specifically, cis-1,4 polyisoprene rubber, butyl rubber, styrene-isoprene block type rubber, styrene-butadiene block type. Elastomers such as rubber, acrylic polymers and silicone rubbers having an epoxy group capable of reacting with an epoxy resin and a latent curing agent. In addition, these may be used alone or in combination of two or more kinds.

The reason why the high heat resistant epoxy resin is used in the thermosetting pressure-sensitive adhesive composition of the present invention is to suppress the decrease in heat resistance due to the addition of the epoxy-modified elastomer and the thermoplastic resin. If the blending ratio of this high heat resistant epoxy resin is too small, the heat resistance will not be exhibited, and if it is too large, the tackiness will be too low, so it is preferably 1 to 200 parts by weight, and more preferably 20 to 150 parts by weight. It is a department.

The high heat resistant epoxy resin is preferably a polyfunctional epoxy resin having three or more functional groups, such as a sulfone-based epoxy resin, a naphthalene-based epoxy resin, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, and a trishydroxyphenylmethane type resin. Epoxy resin,
Examples thereof include tetraphenylol ethane type epoxy resin and dicyclopentadiene phenol type epoxy resin. The sulfone-based epoxy resin has a skeleton containing at least one sulfone group in one molecule, and examples thereof include bisphenol S-type diglycidyl ether epoxy resin. The above-mentioned naphthalene-based epoxy resin has a skeleton containing at least one naphthalene ring in one molecule, and includes naphthol-based and naphthalenediol-based resins, and these may be used alone or in combination of two or more. Can be used.

As the epoxy resin used in the thermosetting adhesive and pressure-sensitive adhesive composition of the present invention, conventionally known epoxy resins can be adopted, and specifically, they are derived from epichlorohydrin and bisphenol A, bisphenol F, bisphenol AD and the like. Bisphenol type epoxy resin, epoxy novolak resin derived from epichlorohydrin and phenol novolac or cresol novolac, glycidyl amine, glycidyl ether, biphenyl, various epoxy compounds having two or more glycidyl groups in one molecule such as alicyclic Etc. Further, these may be used alone or in combination of two or more kinds. For these epoxy resins, it is useful to prevent electron migration by using high-purity products in which impurity ions (sodium ions, chlorine ions, etc.), hydrolyzable chlorine, etc. are reduced to 300 ppm or less.

The reason why the thermoplastic resin is used in the thermosetting pressure-sensitive adhesive composition of the present invention is to make the sheet forming property easier. If the blending ratio of this thermoplastic resin is too small, the effect is not exhibited, and if it is too large, the heat resistance is reduced, so that it is preferably 1 to 200 parts by weight, and more preferably 20 to 150 parts by weight. . As the thermoplastic resin, conventionally known resins can be adopted, and specifically, there are phenoxy resin, polysulfone, polyarylate, polycarbonate, polyphenylene sulfide, polyether sulfone, polyether amide, polyether imide, etc. Alternatively, two or more kinds can be used in combination.

The compounding ratio of the latent curing agent used in the thermosetting adhesive / adhesive composition of the present invention is preferably 1 to 80 parts by weight. As the latent curing agent, conventionally known ones can be adopted, and specifically, Lewis acid complex, dicyandiamide, imidazole compound, acid anhydride curing agent, phenol novolac, aromatic polyamine, amino resin, organic acid hydrazide, diamino. A latent curing agent such as maleonitrile, a melamine derivative, a polyamine salt, an amine imide compound, a molecular sieve-encapsulating curing agent, or a microencapsulating-type curing agent can be used alone or in combination of two or more kinds. When the thermosetting adhesive and pressure-sensitive adhesive composition of the present invention contains a magnetic substance to adhere mounted components such as semiconductor elements, magnetic components and substrates, dicyandiamide having a curing temperature of 160 ° C. or higher is preferable. .

A soft magnetic material can be added to the thermosetting adhesive / adhesive composition of the present invention. This does not cause leakage of the magnetic flux of the mounted component adhered to the pressure-sensitive adhesive sheet when the thermosetting pressure-sensitive adhesive composition is used as the pressure-sensitive adhesive of the pressure-sensitive adhesive sheet,
This is because the magnetic characteristics are not reduced. If the compounding ratio of the soft magnetic material is too small, the desired magnetic flux leakage prevention effect will not be exhibited, and if it is too large, the fluidity of the compounding material will decrease, so 20 to 60% by volume of the total solid content should be compounded. Is preferred.

Examples of the soft magnetic material include Ni / Zn type and Mg.
・ There are Zn type and others.

The method for producing the thermosetting adhesive / adhesive composition of the present invention is a conventional method, for example, an epoxy resin, a thermoplastic resin, a latent curing agent, a high heat resistant epoxy resin and an epoxy-modified elastomer in a solvent. It can be manufactured by uniformly mixing.

To give the thermosetting adhesive / adhesive composition of the present invention magnetic properties, a soft magnetic material may be added to the thermosetting adhesive / adhesive composition. As the soft magnetic material, Ni · Z
There are soft magnetic ferrites represented by n type and Mg.Zn type. It can be appropriately selected according to the purpose and application from the magnetic permeability and the insulation resistance value. Considering the use in electric and electronic fields where insulation is required, it is more preferable to select Ni / Zn based ferrite. The surface of the ferrite may be surface-treated with a silane-based or titanium-based coupling agent.

The thermosetting adhesive / adhesive composition of the present invention can be used as a thermosetting adhesive / adhesive sheet by forming it into a sheet. In this case, a thermosetting adhesive / adhesive sheet can be produced by applying a thermosetting adhesive / adhesive on a release film such as a polyester sheet and removing the solvent at an activation temperature of the latent curing agent or lower.

Further, by dispersing a soft magnetic material in the thermosetting adhesive / adhesive composition of the present invention, the thermosetting adhesive / adhesive composition and the adhesive / adhesive sheet using this composition have magnetic properties. Can have

[0024]

EXAMPLES Examples of the present invention will be described below in detail with reference to Table 1 in comparison with comparative examples. The numerical values in the adhesive composition of Table 1 are parts by weight.

[0025]

[Table 1]

As shown in Table 1, the thermosetting pressure-sensitive adhesive composition according to Example 1 had a bisphenol F type epoxy resin (EXA830LPV manufactured by Dainippon Ink and Chemicals, Inc.) having an epoxy equivalent of 175 as an epoxy resin. 100 parts by weight of a phenoxy resin having a weight average molecular weight of 50,000 (YP-50S manufactured by Tohto Kasei Co., Ltd.) as a thermoplastic resin, 10 parts by weight of dicyandiamide (EH-3636AS manufactured by Asahi Denka Co., Ltd.) as a latent curing agent, and high heat resistance. -Epoxy equivalent of O-cresol novolac type epoxy resin (YDCN-704 manufactured by Tohto Kasei Co., Ltd.)
100 parts by weight and 50 parts by weight of styrene-butadiene block type rubber (Epofriend A1010 manufactured by Daicel Chemical Industries, Ltd.) having an epoxy group as an epoxy-modified elastomer were compounded. The compounding amount of the latent curing agent is measured so that the epoxy group amount of the present epoxy resin solution obtained from the epoxy equivalent and the amine value of dicyandiamide are stoichiometrically equal. This thermosetting adhesive / adhesive composition was prepared by dissolving it in a toluene / MEK (methyl ethyl ketone) 1: 1 mixed solvent to prepare a 35 wt% solution, and this solution was applied on a PET (polyethylene terephthalate) film. When coating with a hair applicator to a thickness of 50 μm after drying, the adhesive surface of the adhesive composition is subjected to silicone release treatment in advance, and then the temperature is set to 80 ° C. after the coating. By drying in a set oven for 5 minutes and peeling from the PET film, the target adhesive / bonding sheet can be obtained. It should be noted that when the product is provided, it is conveyed with the PET film attached.

The evaluation results disclosed in Table 1 are those obtained by evaluating the pressure-sensitive adhesive sheets obtained in the formulations of this example, other examples and comparative examples by the following test methods.

The probe tack test in Table 1 is an evaluation of tackiness, and was measured according to JIS Z 0237. In this test, 1.0 N / 20 cm ² or more is preferable.

The copper foil peeling strength shown in Table 1 was used to evaluate the adhesiveness, and was adopted to evaluate the accuracy as accurately as possible while avoiding the effects of the smoothness of the adhesive surface, parallelism, cleanliness and the like. Specifically, each pressure-sensitive adhesive sheet was sandwiched between an aluminum plate having a thickness of 2 mm and a copper foil having a thickness of 35 μm, and a load of 10 MPa was applied under reduced pressure and heat pressing was performed at 170 ° C. for 60 minutes. Next, an etching treatment was performed to prepare a test piece for peel strength measurement, leaving a copper foil having a width of 10 mm. Peel strength is JIS
It measured based on C6471. In this test, 1.0 kN / m or more is preferable.

The solder heat resistance in Table 1 is an evaluation of heat resistance, and the test piece used for the above copper foil peeling strength is 300.
Peeling from the copper foil was confirmed when it was left standing for 60 seconds in an atmosphere of ° C. In the evaluation shown in Table 1, peeling was visually confirmed to be "x", and peeling was not confirmed to be "o".

In the comprehensive evaluation of Table 1, those which do not satisfy the criteria in the above test results (those which cannot be commercialized) are marked with X, and those which do not meet the criteria are marked with ◯.

In Comparative Example 1, the epoxy-modified elastomer compounded in the composition of Example 1 was not compounded, and in Comparative Example 2, the epoxy-modified elastomer of Example 1 was changed to 150 parts by weight. It is a thing.

Comparative Example 3 is a composition in which the high heat resistant epoxy resin blended in the composition of Example 1 was not blended, and Comparative Example 4 was a composition in which the high heat resistant epoxy resin of Example 1 was blended.
It is changed to 50 parts by weight.

As shown in Comparative Example 1, when the epoxy-modified elastomer was not added, the tackiness was low, and as shown in Comparative Example 2, when the epoxy-modified elastomer was large, the adhesiveness and heat resistance were poor.

As shown in Comparative Example 3, when the high heat resistant epoxy resin was not blended, the adhesiveness and heat resistance were poor, and as shown in Comparative Example 4, when the high heat resistant epoxy resin was large, the adhesiveness was high. Was bad.

Next, a second embodiment will be described. In Example 2, ferrite powder treated with an epoxy-modified silane coupling agent was blended with the varnish of Example 1. The mixing ratio was 50% by volume based on the total solid content of the magnetic substance-containing varnish. Others are manufactured in the same manner as in Example 1.
It was measured.

Although the adhesive / adhesive sheet of Example 2 is not shown in Table 1, the inductance increase rate of Example 2 was 130% when Example 1 was 100%. The inductance increase rate is based on JIS C 5321.

[0038]

According to the present invention, a thermosetting adhesive / adhesive composition having 100 parts by weight of an epoxy resin, 1 to 200 parts by weight of a thermoplastic resin, and 1 to 80 parts by weight of a latent curing agent is used. By containing 1 to 100 parts by weight of the modified elastomer and 1 to 200 parts by weight of the high heat resistant epoxy resin, when the thermosetting pressure-sensitive adhesive composition is formed into a sheet, it can be re-peeled before curing. As a pressure-sensitive adhesive for positioning, it was able to exert its function in good balance as an excellent adhesive after curing.

In another invention, the epoxy resin 100 is used.
1 part by weight, 1 to 200 parts by weight of a thermoplastic resin, and 1 to 80 parts by weight of a latent curing agent in a thermosetting adhesive / adhesive composition, 1 to 100 parts by weight of an epoxy-modified elastomer, and a high heat resistant epoxy resin 1 ˜200 parts by weight and the soft magnetic material were mixed in an amount of 20 to 60% by volume with respect to the total solid content, whereby in addition to the effects of the above invention, leakage of magnetic flux did not occur and magnetic characteristics could not be reduced.

In another invention, a thermosetting adhesive / adhesive sheet obtained by applying the above-mentioned thermosetting adhesive / adhesive composition onto a release film and drying the composition is provided before curing. Was able to be exerted in a well-balanced manner as a removable adhesive sheet for positioning, and as an excellent adhesive sheet after curing.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4J004 AA13 AA18 AB04 CA06 CC02                       DB03 FA05                 4J040 CA091 CA092 DA141 DA142                       DF001 DF002 DM011 DM012                       EC021 EC022 EC061 EC062                       EC071 EC072 EC121 EC122                       EC171 EC172 EC261 EC262                       EC271 EC272 EK031 EK032                       GA11 JB02 KA16 KA33 LA06                       LA08 LA09 NA20 PA23                 5F047 BA23 BA34 BA37 BA52 BA54

Claims (3)

[Claims] 1. A thermosetting adhesive and pressure-sensitive adhesive composition comprising 100 parts by weight of an epoxy resin, 1 to 200 parts by weight of a thermoplastic resin, and 1 to 80 parts by weight of a latent curing agent, and 1 to 100 parts by weight of an epoxy-modified elastomer. And a thermosetting adhesive / adhesive composition containing 1 to 200 parts by weight of a high heat resistant epoxy resin. 2. A thermosetting adhesive and pressure-sensitive adhesive composition comprising 100 parts by weight of an epoxy resin, 1 to 200 parts by weight of a thermoplastic resin, and 1 to 80 parts by weight of a latent curing agent, and 1 to 100 parts by weight of an epoxy-modified elastomer. Parts, high heat resistant epoxy resin 1
~ 200 parts by weight and soft magnetic material to the total solid content of 20 ~
A thermosetting pressure-sensitive adhesive composition containing 60% by volume. 3. A thermosetting adhesive / adhesive sheet obtained by applying the thermosetting adhesive / adhesive composition according to claim 1 or 2 onto a release film and drying the composition.