JPS5991171A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide an adhesive compsn. which has excellent adhesion and heat resistance and scarcely causes resin flow, containing a carboxyl group-contg. nitrile rubber, a poly-N-glycidyl epoxy resin and a specified epoxy compd. CONSTITUTION:An adhesive compsn. consists mainly of a carboxyl group-contg. nitrile rubber, a poly-N-glycidyl epoxy resin, and at least one epoxy compd. selected from glycidyl ethers of alcohols, glycidyl esters of carboxylic acids, glycidyl ethers of phenols (excluding bisphenol A), and an epoxy compd. having a backbone of the formula in the molecule. Furter, fine silica powder and/or clay treated with an onium salt may be added thereto to increase the reliability of adhesion or to inhibit resin flow from a pad during pressing.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an adhesive composition mainly used for producing flexible printed circuits, particularly an adhesive composition having excellent adhesive strength and heat resistance, and having low resin flow.

Conventionally, polyimide film or polyester film is generally used for flexible printed circuit boards.
A-foil was bonded and used as a flexible printed wiring material in many fields such as cameras, calculators, and telephones.

The characteristics required for this adhesive for printed circuit boards include not only the adhesive strength between the film and the gold maple foil, but also electrical properties, solder heat resistance that does not cause abnormalities such as blistering even when immersed in high-temperature molten solder, and circuit These include chemical resistance to solvents such as methylene chloride used when dissolving other layers, and lineability required for free three-dimensional wiring, but the production volume of printed circuit boards is increasing year by year, and circuits are becoming highly complex. With the design of A.

However, conventionally known adhesives for printed circuit boards include fluororesin, epoxy-novolac, nitrile-phenol, polyester, and acrylic adhesives, but they do not have all of the above-mentioned required properties. Combined with the adhesive, there is still no header formula, yet.

In addition, to improve the insulation properties of flexible circuits,
After processing a circuit on a film board with a film and metal foil glued together, adhesive is applied to one side of the film? In many cases, a method of adhering a so-called insulating film that has been applied is used, but conventionally, when this insulating film is heat-pressed, a phenomenon called so-called resin 70 occurs in which the adhesive layer of the insulating film protrudes onto the pad area. I didn't like it.

The present invention has been developed through extensive research in order to overcome these disadvantages found in conventional adhesives for printed circuit boards.

As a result, we have succeeded in developing a high-performance adhesive composition that fully satisfies the above properties, has particularly excellent adhesive properties, and has little resin flow.

That is, in the composition of the present invention, (a) nitrile rubber containing a carboxyl group, (13
) a poly-N-glycidyl type epoxy resin; and (c) at least one epoxy compound selected from the following group. - C-1: Glycidyl ether of flucols.

C-2 = glycidyl ester of carboxylic acids.

C-3: Glycidyl ether of phenols.

Epoxy compound.

In addition, in the present invention, for the purpose of further increasing the reliability of adhesive strength,
Further, in order to suppress resin flow from the butt portion during crimping, finely powdered silica or clay treated with id/and onium salt can be added.

The carboxyl group-containing nitrile rubber of component (a) of the present invention is, for example, an acrylonitrile-butadiene copolymer rubber copolymerized with acrylonitrile and butadiene in a molar ratio of about 5/95 to 45/55, with the terminals of the carboxylated rubber being copolymerized. or a copolymer rubber obtained by terpolymerizing acrylonitrile, butadiene, and a carboxyl group-containing polymerizable monomer such as acrylic acid. The carboxyl group content in the copolymer rubber is preferably about 1 to 8 parts:q6.

(b) Component poly N-glycidyl epoxy resin; 5.
It is a compound having the group shown in 6). Generally, it can be synthesized from the corresponding amine and shrimp halohydrin, but it may also be one in which the amino group of the intermediate is further reacted with an epoxy group to increase the molecular weight.

Examples of component (b) include (5) CH2-OH-(!)1-OH2, \. / (wherein the above R, R#σ represents hydrogen or an alkyl group), and the like.

The epoxy compound of component (C) is the following 0-1, C-2,
One or more types of C-3 and A-4 are used.

C-1: Glycidyl ether of alcohols (6) Examples include the following compounds.

(Diglycidyl ether of polyethylene glycol, where n = 1 to 40), (Diglycidyl ether of polypropylene glycol,
However, lm = 1 to 40), diglycidyl ether of glycerin, trimethio -/
l/F0 Han's tricidyl ether, 1.4-
Diglycidyl ether of butanediol %l.

6-Hexanesiol diglycidyl ether, diglycidyl ether of neopentyl glycol.

C-2: Glycidyl ester of carboxylic acids Examples include the following compounds.

Diglycidyl ester of hexahydrophthalic acid (for example, sold by Showa Denki under the trade name Shodyne 540),
Diglycidyl ester of 7-talic acid (also sold under the trade name Shodyne 508), glycidyl ester of higher fatty acids (Example 1-L' Shell Chemical (Cardura-E from Autopsy)
sold under the product name).

C-3 = Glycidyl ether of phenols (excluding bisphenol A, etc.) The following compounds may be mentioned.

(polyglycidyl ether of phenol novolak), (Polyglycidyl ether of cresol novolak).

(Polyglycidyl ether of brominated phenol novolak), (However, the above 2.p%q is a zero or positive number.) Resorcin, hydroquinone, catechol 17)-/glycidyl ether, bis(hydroxyphenyl)methane Diglycidyl ether (commonly known as bisphenol?), phenyl glycidyl ether, m% p-cresyl glycidyl ether, dibromocresyl glycidyl ether, epoxy obtained by reacting bisphenol A type epoxy resin with polybutadiene having carboxyl groups at both terminals. Compounds (for example, Nippon Soda ■; sold as the Nitsuso Evoxin BPB series).

Epoxy compound.

Examples include the following compounds.

(bis(3,4-epoxycyclohexyl)adipate), (3,4-epoxycyclohexylmethyl 3,4(9
) Mono-Eboxycyclohexane Carpoxylate).

(Bis(3,4-epoxycyclohexylmethyl)oxalate).

0 (bis(3,4-epoxy-6-methylcyclohexylmethyl)adipate), 0 (bis(3,4-epoxycyclohexylmethyl)bislate), (3,4-epoxy-1-methylcyclohexylmethyl 3.4- 0 (6-methyl-3,4-epoxycyclohexylmethyl 6-methyl-3,4-epoxycyclohexanecarboxylate), (3,4-epoxy-5-methyl -cyclohexylmethyl 3.4-epoxy-5-methylcyclohexanecarboxylate), and then the blending ratios of (a), (b), and (c) (by weight)
I will explain about it.

The mixing ratio of the nitrile rubber containing a carboxyl group, which is the component (a), and the poly N-glycidyl type epoxy resin, which is the component (b), is preferably 0.05≦(al/(b)≦19), Outside this range, the adhesive strength tends to decrease.

Furthermore, (a) nitrile rubber containing a carboxyl group, (b) poly N-glycidyl type epoxy resin, and (c
)-r-boxy compound mixing ratio + d, 0.05≦((
It is natural to satisfy the relationship b) + (c)) / (a) 55, and outside this range the adhesion strength may decrease or
When it is less than 0.05, heat resistance also tends to decrease.

In addition to the above (a), (bl, and (c)), a filler can be added in order to improve the adhesive strength and increase the strength of the resin 70. A preferred example is (d) clay treated with finely powdered silica and an onium compound.Of course, both can be used alone or in combination.

A preferable example of fine powder silica is amorphous silica obtained by combustion hydrolysis of silicon tetrachloride in an oxyhydrogen flame, which is sold under the trade name Aerosil (Japan Aerosil Co., Ltd.). ing.

The other component (d), clay treated with an onium compound, is exemplified by bentonite, montmorillonite, sepiolite, etc., and is treated with an ammonium compound,
The clay has improved swelling properties with respect to organic compounds by being treated with an onium compound such as a phosphonium compound or a sulfonium compound, and is also called an organoclay, and is a known substance, and is disclosed in U.S. Pat. No. 2,531.
The manufacturing method and properties are described in detail in , 4j.

Among the onium compounds mentioned above, ammonium compounds are preferable, and include aliphatic amines, alicyclic amines, aromatic amines and heterocyclic amines, primary amines, secondary amines, tertiary amines, etc. Salts of and quaternary ammonium compounds are also preferred examples.

The treatment is usually carried out by suspending clay in water and then adding and reacting with an aqueous solution of an onium compound. Thereafter, means of filtration, washing, drying, and pulverization are applied to obtain the desired product.

(13) This treated clay is commercially available, for example, preferably Ll/l.
'll do Benton 27, Benton 34, Benton 3
JP, Benton BA-38 (N, L, Industry
There are products such as S company).

The above (a) - (b), (c) or H, (a)
When preparing a parabolic adhesive using the components, it is usually sufficient to simply mix three or four of the components, but (a) and ( b), (
A) and (C) or (al, (b) and (C)) may be pre-reacted in advance.

Uninvented V-gradient ml parabolic 1 using ordinary epoxy resin curing agent, nucleating agent, aliphatic and aromatic polyamines, acid anhydrides, hydrazide compounds derived from polycarboxylic acids, Imidazole derivatives, dicyandiamide, guanidine derivatives.

I will cite bisamide derivatives as a representative example.

Specifically, σ, diaminodicyclomethane, bis(4
-amino-3-methylcyclohexyl)methane, diaminodiphenylmethane, diaminodiphenylmethane, 4,
4/-diamino-3, (14) 3I dichlorodiphenylmethane, phthalic anhydride, chlorendic anhydride, Curesol 2E manufactured by Shikoku Kasei Co., Ltd.
4Mz-A21NE, Key 7 Zoll 2E4MZ-(!
There are N1 Kyuryosol 2PZ-ON, etc. Among these, it is most preferable to use aromatic polyamines in terms of adhesiveness and heat resistance.

To accelerate curing, imidazole derivatives, boron trifluoride complexes of amines, Sun Abbott Product D
BU (diazabicycloundecene), U-CAT-8A
NG, 1 (DBU phenol salt)%U-OAT-
8ANQ, 102 (DBU/octylic acid), etc. can be used in combination with the above curing agent as a curing accelerator.

The adhesive composition of the present invention is usually dissolved in a solvent and applied to an adherend. Solvents used in this case include methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, dioxane, ethanol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, chloroform, methylene chloride, dimethyl formamide, etc., and these can be used alone or in combination.

When the above adhesive composition is applied to an adherend, B-staged (semi-cured state, melts when heated), and then compressed with a roll or batch press, it exhibits excellent properties. A printed circuit board is obtained. Crimp swirl surround 80~
Preferably, the temperature is 300° C. and the pressure is 5 to 200 Kp f /ln2. Post-curing at 100 to 350°C can further improve heat resistance.

When crimping requires long-term heating, carboxy Alt
l, 2) Stabilizers can be added to completely prevent IJ rubber and epoxy resin from oxidizing and decomposing. It is preferable to use a non-staining stabilizer that does not cause coloration, such as Irganox 1010' (CjbaGθ1gy
company product, Tetrakis-[Methylene-5-(3/, 5
/-di-t-butyl-4I-hydroxyphenyl)propionate]methane), Ionox 220 (5
Hell Chem product, 4,4I-methylene-bis(2,6-di-t-butyl)phenol), Ionox 3flO (5hell C!hem product, ]-1
Hindered phenol stabilizers such as 3,5-trimethyl-2,4,6-)lis(3,5-di-t-butyl-4-hydroxybenzyl)benzene);
Ouchi Shinkosha product, 4.4/-thiobis(6-t-butyl-3-methyl)phenol).

OA O-6 (Ashland C!hem product%2
．． Thiobisphenol stabilizers such as 2I-thiobis(6-t-butyl-4-methyl)phenol), DLTP(
Stabilizers such as Yoshitomi Pharmaceutical Co., Ltd.'s product, dilauryl thiodipropionate) can be mentioned.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 Two 10' balls in a 500 crn3 separable flask
/2 (Nippon Zeon Co., Ltd., number average molecular weight 30,000, carboxylated nitrile rubber, Mooney viscosity F30 = 60)
34, which is masticated in advance with a roll and cut into small pieces.
OjF, Hiker 0'['BN 1300 X 13 (
Manufactured by Gutdrich, carboxylated nitrile rubber, number average molecule @ 3500, carboxyl base flk2.5
Weight%, viscosity! 550,0000. P, B, (2
7℃)) δ1. Ojl, Ebicuron (17) 830 (manufactured by Dainippon Ink Co., Ltd., bisphenol F type epoxy resin, epoxy weight 174, viscosity 3800 c,
p, s.

(25°C)) 25.0y% Tetradose
000-4000) 22. Of, methyl ethyl ketone 240, and OF were added and dissolved at room temperature to prepare a main ingredient.

Next, a solution prepared by soaking 23.9y of 3.3I-diaminodiphenylsulfone and 1.0y% of diazabicycloundecene as curing agent components in 99.0jll of methyl cellosolve is mixed with 5z of the above base material to form an adhesive. A composition was prepared.

This adhesive solution was applied onto a 25 μm thick Kapton film (polyimide film made by DuPont), dried at 130°C for 10 minutes in an open air environment, and then heated with a 1/2 oz.
1 After rubbing against the treated surface of the copper foil, it was heated for 2 minutes at 0°C and then heated at 20 Kp/cm2.

After 40 minutes of press bonding, the thickness of the adhesive layer of this sample was σ22 to 25 μm. T-type beer 'jM Hike (1
8) It was 1.3 Kp/cm, and no abnormalities such as blistering occurred even when the copper foil was floated in a solder bath at 280° C. for 30 seconds with the copper foil facing down.

Separately, an adhesive solution is applied onto the Kapton film.
After drying at 130°C for 10 minutes, a circular hole with a diameter of 5 words was made and attached to the mirror surface of the copper foil on a press]
After heating at 70℃ for 2 minutes, 170℃, 15 Kp
/cm2 for 40 minutes. The thickness Ff of this adhesive layer was 22 to 25 μm, and the maximum length of the adhesive flowing out into the holes was 0.1 nm or less.

Example 2 In Example 1, instead of Epiclon 830, hydroquinone diglycidyl ether (epoxy equivalent: 123, softening point: 72-77°C) 25. Op to chloroform 200, O
The base ingredients were prepared in the same manner except for using a solution dissolved in F.To dissolve the previously prepared 3,3I-diaminodiphenylsulfone 24.6F and diazabicycloundecene 1.0y in methyl cellosolve 97.7F. Add the curing agent component to the adhesive composition? After 4 f, the same operations as in Example 1 were performed.

T-type beer strength is 1.1 KP/cm at 280℃
There was no abnormality such as blistering even after floating it in a solder bath for 30 seconds +6 Also, when evaluating the resin flow on the mirror surface,
It was 0.1 Im or less.

Example 3 Benton 27 (ML engineering) passed through a 150% mesh sieve in a 500% tyn3 separable flask.
real.

C! Montmorillonite treated with trialkylallylammonium salt manufactured by Chemicals, specific gravity 1.8 (2
5℃)) 14, add OF, and add toluene 12
After adding 1.85* and thoroughly moistening, 95 weight t9
6 Add 4.2 y of ethanol (ft. Stir to form a pre-gel (smooth, ream-like gel) (2 ml). Roll into strands and cut into small pieces.
1 Evolite 400P (product of Kyoeisha Chemical Industry Co., Ltd., polybrobylene glycol dicrycidyl ether, epoxy equivalent 330-360, viscosity 1f15-75 C, P, S,
(256C) ) 30. OF.

Methyl ethyl ketone 216.55i! '(i7 was added and dissolved. Subsequently, tetrad-!30.OF was added to prepare a base component. To this base component, 23.5% of 3.3I-diaminodiphenylsulfone, 71.09f of diazabicycloundecane, 101% of methyl cellosolve A solution dissolved in .89 was added as a curing agent component to obtain an adhesive composition f.

It was coated on a Kapton film and dried at 130°C for 6 minutes, followed by the same operation as in Example 1. T-type beer strength σ1.2Kp
/rm, and no abnormality was observed even when floating in a solder bath at 280°C for 30 seconds6.Also, when the resin flow was measured, it was 0.05 or less.

Examples 4-9 Benton 2714.0 p,) After pregelling with 121.8 ruene and 95 g @ q≦ethanol 4.2y, two balls 107234. Of, Hiker O
T B N 1300 x 13.51.0 p'i was added and dissolved in methyl ethyl ketone 21a5 f. The mixture was stirred at high speed for 50 minutes using a Hiroku Tsuzuroku Homomixer to uniformly disperse the mixture. The epoxy resin shown in Table 1 and curing agent components were added to each of these to prepare an adhesive composition, and Kapton and copper foil were bonded. The results are shown in Table 1. However, the drying conditions are 1
The press conditions were 30°C for 6 minutes and 170°C for 40 minutes.

(21) (22) r+ 1) Kyoeisha Chemical Industry Co., Ltd. product, ethylene glycol diglycidyl ether, epoxy t125-1
45, viscosity 15-35 C, P, S, (25°C) epoxy equivalent 100, viscosity 〒000. P, S, (25℃
) Note 3) Sakamoto Yakuhin Z, g, epoxy equivalent 164, stickiness 8.2 (!, P, S, (20℃) Note 4) Japan v! Lada's product, carboxylated butadiene rubber on both ends with bisphenol A 7%4. j Modified with epoxy resin 504≦Methyl ethyl solution, epoxy total 1600-2100% Viscosity 60-80 C! , P
, S, (25°C) Note 5) Showa Denko product, hexahydrophthalic acid diglycidyl ester, ``boxy'' 5 amount 1
+5~160, viscosity 200~400 C, P, S, (
25℃) Note 6) Nippon Kayaku Co., Ltd. product, phenol novolac type epoxy resin, epoxy fi 175-195,
Softening point: 65-75°C (7) Union Carbide product, 3.4-mm (23
) Boxycyclohexylmethyl 3.4-epoxycyclohexanecarboxylate, t131-14 per epoxy
3. Viscosity change 350-4500. P.8. (25℃) Note 8
) 3% 3'-diaminodiphenylsulfone Note 9)
Diazabicycloundecene Example 10 Bentone 27% 14. OF,) After mixing 121 By of toluene and 4.2 Y of 95 v'f#% ethanol to form Brigel, N1pol 107259.5,
P% No 1 Squid-CTBN 1300X132a5, F
, Evolite 40E2XOp.

Tetrado! 23. Ojl+ was added and mixed with 216.57 ml of methyl ethyl ketone to obtain a main ingredient. 4.4I-diaminodiphenylmethane 1a9p and diazabicycloundecene 1.0y were dissolved in methyl cellosolve 112.81, mixed with the main component, and bonded between Kapton film and copper foil in the same manner as in Example fl13. T-type peel agony σ
It was 1.2 Kp/cm, and no abnormality was observed even when it was floated in a 280° C. solder bath for 30 seconds. When the resin flow was measured, it was less than 0.05 m.

Example 11 (24) Nibo A, 1072.34. Op 1 hiker CT
BN 1300X13. 51.091, Evolite 100 MF' (Kyoeisha Ihigaku Kogyo product, trimethylolpropane triglycidyl ether, epoxy equivalent 135-1ri5, K 9100-160 (:
! , P, S, (25°C) ) 23.09, tetrad-! 23.07 plus methyl ethyl ketone 216
．． After dissolving with 5 rinsing +, +, Erosil #F: 3UO (product of Nippon Aerosil Co., Ltd.).

Powdered silica) 10.0y was added and homomixer was used to
Stir at high speed for a minute to uniformly distribute the base ingredient. , 3.3'-sia is fudiphenyl sulfone 23. zy, diazabicycloundecene 1. The solution dissolved in 70.99% Oy%-methyl heptarosolve was mixed with the main ingredient and the same operation as in Example 1 was carried out. Tff1ll Building strength (Ke1.2 Hp
lon, and even if floated for 30 seconds in a 280°C half H1 bath, the total < id constant V:r;J! It was mera f1 catty. When I looked at the resin flow, it was less than 0.05M.

Patent applicant Mitsui Petrochemical Industries Co., Ltd. agent Patent attorney Masao Inoue (25) Procedural amendment dated January 26, 1981 Kazuo Wakasugi, Commissioner of the Patent Office 2 Title of invention Adhesive composition 3 Make amendments Relationship with the Patent Case Patent Applicant Address 3-2-5 Kasumigaseki, Chiyoda-ku, Tokyo Name (
(Name) (58B) Mitsui Petrochemical Industries Co., Ltd. Representative Shimono Tanawa 4, Agent Address: 240-01 K.
1601-636 Nagara, Hayama-machi, Miura-gun, Kanagawa Prefecture Number of inventions increased by amendment None 7, Subject of amendment (1) [Nitrile containing carboxyl group which is component (a)] on page 12 of the specification, lines 1-2 Rubber and] wo (c
) with the epoxy compound that is the component.”

(2) Jo on page 12, line 3, o5≦(a)/(b)
≦19” is corrected to “o, o5≦(c) / (b)≦19J.

(3) 10.05≦((b)+(
c)) /(a)≦51 [o, o5≦((b)+(c
)) Correct as /(a)≦21.

Agent: Patent Attorney Masaru Inoue Written amendment to life procedure 1, Indication of case: 1982 Patent Application No. 20004 [1 No. 2, Title of invention: Adhesive composition 3, Relationship with the case of the person making the amendment: Address of patent applicant 3-2-5 Kasumigaseki, Chiyoda-ku, Tokyo Name (588) Mitsui Petrochemical Industries Co., Ltd. Representative Seiki Nakano 4, Agent 240-01 Address 1801-83 Nagara, Hayama-cho, Miura-gun, Kanagawa Prefecture
5. The number of inventions increased by the amendment 16. The amendments are made as follows: 16. The column for the title of the invention, the column for the scope of claims, the column for the detailed description of the invention, and the printed circuit board in the specification to be amended.

(2) The claims section on page 1 of the specification is amended as shown in the attached sheet.

(3) “Regarding adhesive compositions” on page 2, line 4 of the same page.
be amended to "Relate to adhesive compositions and printed circuit boards."

(4) "Polyester film" in the 6th line of page 2 is corrected to "heat-resistant plastic film such as polyester film."

(5) On page 3, lines 17-18, “adhesive composition” is replaced with “
"Adhesive composition and printed circuit board using the composition".

(6) Insert the following sentence between page 17, line 9 and line 1θ.

``The thus produced substrate in which the heat-resistant plastic film and metal foil are firmly bonded is extremely excellent as a printed circuit board, especially a flexible printed circuit board.'' (7) r20Kg/am2J, page 18, line 18 of the same. is corrected to r40Kg/cm 2.

(8) r 15Kg/ crs2 on page 19, line 8
Correct J to r40Kg/Cff12.

(8) "Trialkylaryl ammonia" on page 20, line 9 of the same document is corrected to "trialkylaryl ammonia".

Attachment 2. Claim 1: An adhesive composition containing the following (a), (b), and (c) as main components.

(a) Nitrile rubber containing carboxyl groups, (b)
Poly N-glycidyl type epoxy resin, (c) C-1 below
, C-2, C-3, and C-4.

C-1: Glycidyl ether of alcohol.

C-2 = glycidyl ester of carboxylic acids.

C-3 Niphenols (excluding bisphenol A)
glycidyl ether.

C-4=Epoxy compound having a skeleton represented by 00 in the molecule.

2. The adhesive composition according to claim 1, wherein the adhesive composition contains, as component (d), finely powdered silica or/and clay treated with an onium compound.

3. The epoxy resin is made of plastic and then printed.
”

Claims (1)

[Claims] 1. An adhesive composition containing the following (a), (b), and (c) as main components. (a) Nitrile rubber containing carboxyl groups, (b)
Poly N-glycidyl type epoxy resin, (cl C-1
% C-2, C-3, and C-4 epoxy compounds. 0-1: Glycidyl ether of alcohol. C-2: Glycidyl ester of carboxylic acids. C-3: Phenols (excluding bisphenol A)
glycidyl ether. Epoxy compound. 2. The adhesive composition according to claim 1, wherein the adhesive composition contains (d) clay treated with finely powdered silica and/or an onium compound as the W component.