JPH07197000A - Heat-resistant adhesive - Google Patents

Abstract

PURPOSE:To obtain a heat-resistant adhesive consisting of an epoxy resin, an alcohol-soluble polyamide resin, a styrene-based thermoplastic elastomer and a curing agent and remarkably improved in resistance to soldering temperature, adhesiveness, electric characteristics, softness, high-temperature peeling resistance, etc. CONSTITUTION:This adhesive consists of (A) 100 pts.wt. of an epoxy resin having two or more epoxy groups (e.g. bisphenol A type epoxy resin), (B) 10-25 pts.wt. of an alcohol-soluble polyamide resin having 100-150 average amide group equivalent (preferably a terpolymer such as nylon 6.66.610 terpolymer having 120-180 deg.C melting point), (C) 5-10 pts.wt. of a styrene-based thermoplastic elastomer [preferably in the elastomer, both terminal phases are polystyrene phases and the intermediate phase is a rubber phase such as polybutadiene and a weight ratio of the styrene phases to the rubber phase is (13/87) to (50/50) and the molecular weight is 50000-2000001 and (D) a curing agent (preferably dicyandiamide). Furthermore, the blend amount of the component D is preferably 0.05-120 pts.wt. based on 100 pts. wt. of the component A.

Description

Detailed Description of the Invention

[0001]

[Industrial application] Heat-resistant thermosetting adhesives, especially T
The present invention relates to a heat-resistant adhesive having excellent solder heat resistance, adhesiveness, electrical properties, chemical resistance, flexibility, etc. for AB (abbreviation of Tape Automated Bonding).

[0002]

2. Description of the Related Art As an adhesive used for electric and electronic purposes, for example, a means for mounting an IC chip on an electric device is used.
Soldering heat resistance, adhesiveness, electrical characteristics,
Although some require chemical resistance, flexibility, etc., no adhesive yet satisfies these properties at a high level.
For example, it has been pointed out that epoxy resin has relatively high heat resistance but lacks flexibility, and also has poor adhesiveness, especially in the peeling property at high temperatures of 150 ° C or higher. It has also been pointed out that polyimide resins and the like, which are known as heat resistant resins, also have poor peeling properties. It is known to mix a polyamide resin with an epoxy resin as a method for improving the high temperature peeling property, and the present inventors have also filed Japanese Patent Application No. 5-244763, Japanese Patent Application No. 5-44763.
An improvement example was introduced in 273467. However, epoxy resin-
There is a strong demand for improvement in heat resistance of polyamide resin-based composite adhesives, and further improvement is desired. Epoxy resin
Some polyamide resins are blended with acrylonitrile rubber (NBR), but they are not preferable because they have drawbacks such as mainly high temperature peelability and poor heat aging resistance.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides heat resistance, solder heat resistance, adhesiveness, electrical characteristics, flexibility, high temperature peelability, chemical resistance, etc. of conventional epoxy resin-polyamide resin composite adhesives. It is another object of the present invention to provide a further improved heat resistant adhesive.

[0004]

In order to solve the above problems, the present inventors have found that heat resistance is improved by adding a styrene-based thermoplastic elastomer to a combination of a conventionally used epoxy resin and alcohol-soluble polyamide resin. The present invention has been completed by finding out that it is improved, and examining the kind of resin, composition ratio and the like in detail. The gist of the present invention is to use 100 parts by weight of at least one epoxy resin selected from epoxy resins having at least two epoxy groups in one molecule and an alcohol-soluble polyamide resin having an average amide group equivalent of 100 to 150. It is a heat-resistant adhesive comprising -25 parts by weight, 5-10 parts by weight of a styrene-based thermoplastic elastomer, and a curing agent.

The epoxy resin used in the present invention is at least one kind of epoxy resin selected from epoxy resins having at least two epoxy groups in one molecule, and examples thereof include bisphenol A type epoxy, bisphenol F type epoxy and phenol novolac. Type epoxy, cresol type epoxy, brominated bisphenol type epoxy, brominated novolac type epoxy, alcohol modified phenol type epoxy, dimer acid / trimer acid modified epoxy, polyethylene glycol modified epoxy, alicyclic epoxy,
Examples thereof include naphthalene type epoxy, and these epoxy resins may be used alone or in combination of two or more kinds as required.

Next, as the alcohol-soluble polyamide resin, a binary copolymer such as 6.66 is used as a copolymer.
・ Ternary copolymer such as 610, 6.66 ・ 12, 6,66 ・ 610 ・
Examples thereof include quaternary copolymers such as 12. These polyamide resins may be used alone or in combination of two or more as needed. Among the above-mentioned polyamide resins, those which are soluble in lower alcohols such as methanol and ethanol are preferable, and the alcohol-soluble polyamide resin of terpolymer from the viewpoint of solder heat resistance, high temperature peelability and availability. Is used. The melting point of these alcohol-soluble polyamide resins is 80 to 210 ° C, of which the melting point in the present invention is
Those having a temperature of 120 to 180 ° C. are preferably used. Melting point 180
When the temperature is higher than ℃, the high temperature peeling property is lowered, and when the temperature is lower than 120 ° C, the solder heat resistance is lowered, which is not preferable. Further, ordinary polyamide resins such as nylon 6 and nylon 66 have a high melting point of 210 ° C. or higher and are insoluble in organic solvents, which is not preferable. The amide group equivalent is preferably 100 to 150, and since these are solvent-soluble copolymers, the adhesiveness is further improved. Specifically, Amilan CM4000
(Product name of Toray, 6,66,610 terpolymer polyamide resin), 4001 (same as above, 6.66.610 terpolymer polyamide resin), 8000 (same as before, 6.66)・ 610 terpolymer polyamide resin), PlataBond M995 (product name manufactured by Rilsan Japan Co., Ltd., 6,66,610 terpolymer polyamide resin), M1276
(Same as above, 6.66.610 terpolymer polyamide resin), Daiamide T171 (trade name of Daicel Huls Co., 6,66.610 terpolymer polyamide resin), T170 (Same as above, 6. 66.610 terpolymer polyamide resin) and the like.

The greatest feature of the present invention is that the epoxy resin
This is to improve the heat resistance by adding a styrene thermoplastic elastomer to the polyamide resin composite adhesive.
This styrene thermoplastic elastomer has a polystyrene phase in both terminal phases, polybutadiene in the intermediate phase,
It has a rubber phase of polyisoprene, ethylene-butylene, or hydrogenated type polyolefin, and the weight ratio of the styrene phase and the rubber phase is 13 / 87-50 / 50, and the molecular weight is 50,000-200,000. preferable. Specific examples include TR1101 (trade name, manufactured by Shell Chemical Co., intermediate phase / molecular weight: butadiene / 100,000 to 200,000), D1111 (same as above, isoprene / about 100,000), G1650 (same as above, ethylene-butylene / about 100,000). , G1652 (Same as above, ethylene-butylene / about 100,000), G1726 (Same as above, ethylene-
Butylene / approx. 100,000), FG1901X (same as above, ethylene-
Butadiene / about 100,000) and the like.

The mixing ratio of each component is such that the amide group equivalent is 100 to 150 relative to 100 parts by weight of the base epoxy resin.
When the alcohol-soluble polyamide resin is more than 25 parts by weight, the electrical properties and solder heat resistance are remarkably deteriorated due to the hygroscopicity of the polyamide resin. I can't stand it. When the amount of the styrene-based thermoplastic elastomer exceeds 10 parts by weight, the high temperature peeling property is deteriorated, and when it is less than 5 parts by weight, the heat resistance is not improved, which is not preferable.

The curing agent is used in an amount of 0.05 to 120 parts by weight based on 100 parts by weight of the epoxy resin. As the curing agent, one or two or more types of curing agents generally used for epoxy resins, such as amine type, organic acid anhydride type, phenol type, dicyandiamide type, amidoamino type and imidazole type, can be used. Specifically, diaminodiphenylmethane, diaminodiphenyl sulfone, methyl hydrophthalic anhydride, methyl tetraphthalic anhydride, dicyandiamide, 2-ethyl-4-methylimidazole, 4-
Methyl imidazole and the like can be mentioned, but it is preferable to use diaminodiphenylmethane or dicyandiamide particularly in view of excellent electrical characteristics and solder heat resistance. The amount of each curing agent added is 5 to 30 parts by weight of amine system, 5 to 120 parts by weight of organic acid anhydride system, 1 to 80 parts by weight of phenol system, 1 to 10 parts by weight of dicyandiamide system, and 10 to 70 parts by weight of amidoamino system. And 0.05 to 10 parts by weight of imidazole type is preferable.

The adhesive of the present invention is manufactured, for example, by the following method. First, an alcohol-soluble polyamide resin is dissolved by stirring in a lower alcohol such as methanol at 50 to 80 ° C., an epoxy resin and a thermoplastic elastomer are added thereto, and the mixture is heated and stirred at 50 to 80 ° C. and sufficiently mixed. In this case, the epoxy resin to be charged is preheated to 50 to 80 ° C, or chlorinated hydrocarbons (methylene chloride, chloroform, carbon tetrachloride, trichloroethylene, tetrachloroethylene, etc.), ketone hydrocarbons (acetone, methyl ethyl ketone, Methyl isobutyl ketone etc.) and aromatic hydrocarbons (benzene, toluene, xylene etc.) dissolved in are used for good mixing efficiency. Next, styrene-based thermoplastic elastomer with chlorinated hydrocarbons (chloroform, carbon tetrachloride, trichloroethylene, tetrachloroethylene, etc.) and aromatic hydrocarbons (benzene, toluene, xylene, etc.) dissolved with stirring at 50-80 ° C. Add. The thermoplastic elastomer is dissolved in advance with stirring in an organic solvent such as benzene, toluene or xylene at 50 to 80 ° C. The epoxy resin and the thermoplastic elastomer are added to the polyamide solution simultaneously or separately. After sufficiently stirring, the mixture is cooled to 40 ° C. or lower, preferably 5 to 20 ° C., after which a curing agent is added, the mixture is further stirred and dissolved at 5 to 20 ° C., and then left to stand for 30 to 60 minutes for degassing. An example of the use of the adhesive thus obtained is to coat a plastic film of polyimide, polyester, or the like so that the thickness after drying is 5 to 50 μm.
Drying and curing at ℃, especially 90 ~ 120 ℃, metal foil (copper foil,
A film for TAB is obtained by laminating Al foil: 19 to 35 μm, cured under heating at 120 to 300 ° C., and then subjected to imaging (resist, exposure, development), etching, etc. to form an electric circuit. Used as.

[0011]

EXAMPLES The embodiments of the present invention will now be described in detail with reference to examples, but the present invention is not limited thereto. (Example 1) Bisphenol A type epoxy resin having an epoxy equivalent of 189: 100 parts by weight of Epicoat 828 (trade name, manufactured by Yuka Shell Co., Ltd.), 6.66.610 nylon copolymer resin Amilan CM4000 (having a melting point of 140 ° C.) 15 parts by weight of Toray Co., Ltd. (trade name) is added to methanol, and the mixture is stirred and dissolved at 60 ° C., and then added to the epoxy resin prepared in the stirring and mixing tank, and further stirred and mixed at 60 ° C. Separately, the styrene / rubber ratio is 28 /
Styrene-ethylene / butylene-styrene copolymer of 72 which is a styrene-based thermoplastic elastomer: Kraton G-FG1901X (trade name of Shell Chemical Co., Ltd.) 6 parts by weight is put into toluene and stirred and dissolved at 80 ° C., Put it into the epoxy-polyamide resin solution that was previously mixed, and then add 60 ℃
Stir to mix. After thoroughly mixing, the mixture was cooled to 20 ° C., 20 parts by weight of diaminodiphenylmethane (DDM) was added to the cooled epoxy-polyamide-styrene thermoplastic elastomer mixed solution, and the mixture was further stirred and mixed, and then left standing for 60 minutes. To obtain an adhesive solution. This adhesive solution is applied to a 75 μm thick polyimide resin film: Upilex S (trade name, manufactured by Ube Industries, Ltd.) and dried at 90 ° C. for 5 minutes to a semi-cured state. 1 ounce copper foil (thickness) A 75 μm-thick rolled copper foil manufactured by Nikko Kyokushi Co., Ltd.) was laminated by thermocompression bonding at 160 ° C. for 30 minutes to obtain a cured laminate (film for TAB). Table 1 shows the physical property measurement results.
Shown in.

(Example 2) An adhesive was prepared in the same manner as in Example 1 except that 9 parts by weight of the styrene thermoplastic elastomer was used to prepare a polyimide resin film-adhesive-copper foil cured laminate (TAB). Film) to measure the physical properties,
The results are also shown in Table 1.

Comparative Examples 1 to 3 In the same manner as in Example 1, except that the styrene-based thermoplastic elastomer was changed to 0, 2, and 20 parts by weight, the same treatment was performed to prepare an adhesive, and a polyimide resin film-adhesive- Copper foil cured laminate (TAB film)
Then, the physical properties were measured, and the results are also shown in Table 1.

(Comparative Examples 4 and 5) A polyimide resin film was prepared in the same manner as in Example 1 except that the polyamide resin was 5, 50 parts by weight and the styrene thermoplastic elastomer was 8 parts by weight. -Adhesive-Copper foil cured laminate (film for TAB) was obtained and the physical properties were measured, and the results are also shown in Table 1.

(Examples 3 to 4) The same procedure as in Example 1 was repeated except that the polyamide resin was changed to 20 parts by weight and the styrene-based thermoplastic elastomer was changed to 6 and 9 parts by weight to prepare adhesives. -Adhesive-Copper foil cured laminate (film for TAB) was obtained and the physical properties were measured, and the results are also shown in Table 1.

Comparative Example 6 NBR: NIPOL 1072J was used instead of the styrene thermoplastic elastomer in Example 1.
(Nippon Zeon product name, bound acrylonitrile amount: 27
%) In the same manner as above to prepare an adhesive, obtain a polyimide resin film-adhesive-copper foil cured laminate (film for TAB) and measure its physical properties. It was also written in 1.

[0017]

[Table 1]

(Physical property measuring method) 1) Solder heat resistance: According to JIS C 6481, a sample is cut into 2.5 cm square with a cutter knife and floated in a solder bath, and the appearance such as blistering of the sample for 30 seconds at each temperature. The maximum temperature with no change was set. 2) High temperature peelability: Width of sample is 1 cm x according to JIS C 6481
The sample was fixed on a hot plate kept at 150 ° C by cutting with a cutter knife to a length of 20 cm, and 180 ° peel was measured and determined.
(Tensile tester manufactured by Shimadzu Corporation) 3) Heat aging resistance: The sample was aged for 240 hours in an oven kept at 150 ° C for a width of 1
cm × 20cm length cut with a cutter knife and 90 ° at room temperature
The peel was measured. (Shimadzu tensile tester) 4) Flexibility: adhesive solution of polyimide resin film 75μ
The sample coated on m was dried in an oven kept at 90 ° C. for 5 minutes to be in a semi-cured state. The sample was bent 180 ° with the adhesive on the outside and cracks were observed.
(○… No cracking. ×… cracking) 5) Volume resistance: After cutting the sample into 11 cm × 11 cm according to JIS C 6481, leave it in an atmosphere of 20 ° C. × 60% RH for 96 hours, and then up and down the diameter 80φ. It was sandwiched between electrodes and measured.

[0019]

INDUSTRIAL APPLICABILITY According to the present invention, as a heat resistant thermosetting adhesive, particularly for TAB (abbreviation of Tape Automated Bonding), solder heat resistance, adhesiveness, electrical characteristics, chemical resistance, flexibility, etc. An excellent heat-resistant adhesive is obtained, and its utility value is extremely high in industry.

Claims (1)

[Claims] 1. 100 parts by weight of at least one epoxy resin selected from epoxy resins having at least two epoxy groups in one molecule and an average amide group equivalent of 100.
A heat-resistant adhesive comprising: 10 to 25 parts by weight of an alcohol-soluble polyamide resin of 150 to 5 parts by weight, 5 to 10 parts by weight of a styrene-based thermoplastic elastomer, and a curing agent.