JPS62235382A - Thermosetting adhesive film - Google Patents

Abstract

PURPOSE:To obtain the title thermosetting adhesive film having excellent film- forming property, flexibility and heat-resistance and suitable for various bonding purposes, by compounding a specific polyimide with a specific maleimide and casting the obtained composition. CONSTITUTION:The objective adhesive film can be produced by casting a composition produced by compounding (A) a polyimide of formula I {Ar is bivalent group composed of bis[4-(3-aminophenoxy)phenyl]-sulfone and 3,3'- diaminodiphenylsulfone at a molar ratio of 100:0-50:50} and (B) a polymaleimide of formula II (R is >=2C group having integral valence; n is integer of >=2) preferably at an A:B ratio of 90:10-50:50.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermosetting adhesive film having excellent flexibility and heat resistance.

[Conventional technology]

Conventionally, as a polyimide adhesive used for electrical insulating materials, structural materials, etc., a pre-attached material made of N,N'-(4,4-cyphenylmethane) bismaleimide and 4,4'-diaminodiphenylmethane is known. ing.

[Problem that the invention seeks to solve]

However, the precondensate itself could not be cast into a film because it was brittle (i!i1<).

Furthermore, in order to use adhesive sheets for laminated materials, etc., the solution must be impregnated into a base material such as glass cloth, and then the solvent must be removed to form a prepreg, which is limited by the thickness of the base material. I couldn't get it.

The situation is related to the present invention! I2 is considered to be
5'J It is an object of the present invention to provide a thermosetting adhesive film having excellent flexibility and heat resistance.

[Means for solving problems]

According to the present invention, the purpose is to provide a polyimide (A) represented by the following general formula.

Resin acid compound mixed with polymaleimide (B) represented by the general formula '4! : Achieved by an adhesive film obtained by casting.

In the present invention, polyimide (8) is prepared as 5.5',4.4'-benzophenonetetracarboxylic dianhydride (hereinafter referred to as BTDA!: abbreviated as f) in a solvent such as cresol or phenol.
,! : Bis(4-(3-aminophenoxy)phenylsulfone (hereinafter abbreviated as m-APPS)) and 3,3'-diaminodiphenylsulfone [abbreviated as 3゜3'-DDS] and stirred under heating. However, the corresponding polyamic acid is synthesized by reacting it in an aprotic polar solvent such as dimethylacetamide or dimethylformamide at a temperature below room temperature, and then acetic anhydride-dehydrating agent such as pyridine? It can also be obtained by dehydration and ring closure.

m-APPS and 5.5'-DDS in polyimide (4)
The molar ratio of 3.3' is preferably 100:O to 50:50.
- If the DDS content is more than 50 mol %, the polyimide (5) becomes hard and film forming properties deteriorate.

Specific examples of the polymaleimide tB) that can be used in the present invention include N, N'-(4,4'-diphenylmethane) bismaleimide, N, N'-(4,4'-diphenylmethane), Maleimide, NsN' 1)-
Phenylene bismaleimide, N,N'-m-phenylene bismaleimide, N,N'-2,4-)rylene bisma L
/(mido, N, N'-2,6-tolylene bismaleimide, N, N'-ethylene bismaleimide)", N
There are polymerimides represented by the following structural formulas: , N'-hegynamethelene bismaleimide, or the like, and these stiffeners can be used alone or in a mixture of two or more kinds.

The mixing ratio of polyimide prisoner and polymaleimide tB) is 10 to 10 to polymaleimide IB) χ polyimide (8).
It is preferably used at 50% by weight, more preferably 1
5 to 30% of children. When the amount of polymaleimide (B) is less than 10% by weight and 11%, curing is insufficient, and when it is more than 50% by weight, the resin composition becomes brittle and lacks moldability.

Mixture of polyimide and polymaleimide 4! Although r may be carried out in powder form, it is usually carried out by adding and dissolving the polymaleimide in polyamide foam dissolved in a bath agent such as DMF.

The thus obtained mixed varnish of polyimide and polymaleimide Kaoru glass fi! , cast onto a stainless steel plate, etc., and dry to obtain an adhesive film. The drying temperature and time vary depending on the bath agent used and the type S of the polymerimide, but the temperature must be kept lower than the temperature at which the reaction of the polymaleimide becomes noticeable, and the drying time should be set so that the amount of residual solvent is 1% or less. There must be.

After the obtained adhesive film is overlapped with the adherend.

Molded products with excellent heat resistance and good adhesive strength by heating and pressurizing at temperatures above the softening point. Obtainable.

Since the contact W74 lumen according to the present invention has high El flexibility, it is used as an adhesive for a heat-resistant film on a copper foil of a flexible wiring board.

The present invention will be described in detail below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 BTDA32.2g, m-APP834.6g%3.3
5.0 g of '-DDS was placed in a four-hole flask equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, and a cooling tube, and 646 g of m-cresol and 108 g of luene were added thereto, followed by heating and stirring while flowing nitrogen gas. The reaction was carried out at 150 to 160°C for 16 hours to obtain a polyimide film having a resin content of 216% and a viscosity of 7P. This polyimide varnish was poured into acetone and sedated, pulverized, washed and dried to obtain polyimide powder. Reduced viscosity of polyimide powder (0.1g per degree)
/di, solvent N, N-dimethylformamide (DMF)
, temperature 3α0°C was 1151 dl/g. 100g of the obtained polyimide powder and N,N'-(4,4'-
diphenylmethane) bismaleimide (BMI) 10g
't' It was dissolved in 400 g of DMF to make a festival. This varnish was poured onto a glass plate, dried at 130°C for 10 minutes, peeled off, fixed on an iron frame, and dried at 200°C for 1 hour to obtain an adhesive film. The resulting adhesive film had a thickness of 25 μm, a residual solvent i of 1%, a softening point of 220° C., and was excellent in flexibility without cracking even when bent at 180°.

Example 2 The same procedure as in Example 1 was carried out except that 20 g of BMI-M (polymaleimide manufactured by Mitsui Toatsu Chemical Co., Ltd.) was added instead of N,N'-(4,4'-cyphenylmethane bismaleimide). An adhesive film was obtained. The obtained Wc column film had a thickness of 25 urn, a residual solvent amount of 1.1%, and a softening point of 220°C.
It did not crack even when bent at 180 degrees and had excellent flexibility.

Comparative Example 1 Kelimide 601 (polyamino bismaleimide A4 resin manufactured by Nippon Polyimide ■) 100 g'kDMF100 g
After casting on a varnish glass machine with K melted, 130℃10
It was then dried for 170" and 20 minutes, but it was brittle and did not form a film.

Examples 3-5. Comparative Examples 2 to 3 Example 10a An adhesive film obtained in the same manner as Example 1 except that the MBI was changed as shown in Table 1 was sandwiched between a 1 mm thick aluminum temporary and a 35 μm # single-sided roughened steel foil. 50kg
Lamination was performed under f/aIP conditions at 275° C. for 30 minutes to obtain a steel-clad base f2. The buttocks of the board? It is shown in Table 1.

Table 1 The softening point was measured by the Penetrate Shirashi method at a load of 25 kg/aIF and a heating rate of 10° C./sea bream.

Steel foil peel strength is 90 at tensile speed K 50 mm 7wm
゜Peel strength was measured.

The heat resistance was determined by floating a 20111111 square test piece on a solder bath with the steel foil facing down, and then observing the presence or absence of bulges.

Example 6 A 50 μm rhinoceros polyimide film and a 35 μm thick single-sided roughened steel foil were sandwiched between one sheet of the adhesive) 4 AL' obtained in Example 1 and laminated at 275° C. and 50 kgf/a IF for 30 minutes. Free beef ciple printing layout [i1 Shuki! &ke got it. The 90° copper foil peel strength of this board is 50 mm/m.
=2.6kgf/CrB115 at room temperature
It was 2.1 kgf/e11 at 0°C.

-! Riko's board was immersed in a 300°C solder bath for 1 minute, but no blistering occurred.

Example 7 An adhesive film χ was produced in the same manner as in Example 1 except that the BMI amount was changed to 30 phr. This adhesive film and 35 μm single-sided roughened copper foil were layered on both sides of a 508°C thick polyimide film at 275°C.

Lamination was carried out under conditions of 50 kgf# and 30 minutes to obtain a substrate for a flexible printing distribution board.

The 90° copper foil peel strength of this board is 2°4 kgf at room temperature.
/cm, 2.0 kgf/Cm at 150℃,
No blistering occurred even after immersion in a 300°C solder bath for 1 minute.

Example 8 A flexible printed wiring board was prepared in the same manner as in Example 7 using a film-like lubricant prepared in the same manner as in Example 1 except that 15 g of BMI-M (Mitsui Toatsu Chemical Polymaleimide) was used instead of BMI. I got a board for use. 90° of this board
Copper foil peel strength is 2.4 kgf/cm at room temperature, 1
It was 1.9 kgf/cm at 50°C, and no blistering occurred even when immersed in a 300°C solder bath for 1 minute.

Comparative Example 4 In place of the adhesive film according to the present invention, Baylarac (acrylic film adhesive manufactured by Chebon Co., Ltd.) was used.% Same mg as in Example 6, 180'C130 kgf/at,
Lamination was carried out for 60 minutes to obtain a substrate for a flexible printed wiring board. The 900 copper foil peel strength of this board is 2.
2 kgf/Cm, 16 kgf/Cm at 150℃
Met. Further, when this board was immersed in a 300° C. solder bath for 1 minute, blistering occurred.

〔Effect of the invention〕

Claims (1)

[Claims] 1. General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, Ar is the molar ratio of ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ and ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ 100:
0 to 50:50 (represents a divalent group with a ratio of 0 to 50:50) General formula ▲ Numerical formula, chemical formula, table, etc. are available for polyimide (A) represented by A thermosetting adhesive film obtained by casting a composition containing a polymaleimide (B) represented by the formula (n is an integer of 2 or more). 2. Ratio of polyimide (A) and polymaleimide (B) (
The thermosetting adhesive film according to claim 1, wherein A:B) is 90:10 to 50:50.