JPS6381139A - Prepreg for bonding - Google Patents

Abstract

PURPOSE:To obtain a prepreg for bonding, by impregnating a solution of a resin composition composed of a polyfunctional cyanic acid ester resin composition and an amorphous thermoplastic saturated polyester resin in a drawn porous tetrafluoroethylene resin sheet, etc., and drying the impregnated solution. CONSTITUTION:A solution of a thermosetting resin composition having a concentration of 20-60wt% and containing (A) 30-95pts.wt. of a resin composition containing a polyfunctional cyanic acid ester having >=2 cyanato groups in the molecule (preferably 1,3-dicyanatobenzene, etc.) or a prepolymer having a number-average molecular weight of 300-6,000 and (B) 70-5pts.wt. of an amorphous thermoplastic saturated polyester resin having a number-average molecular weight of preferably 5,000-22,000 and hydroxyl value of preferably 1-30mg.KOH/g as essential components is impregnated in (C) a drawn sheet or film of porous tetrafluoroethylene resin and the solution is dried to convert the resin component to semi-cured state and obtain the objective prepreg containing 30-80wt% resins.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention has excellent physical properties such as low dielectric constant, high electrical insulation, high heat resistance, flexibility, low moisture absorption, and high adhesiveness, and It is an adhesive prepreg with low embeddability and excellent embeddability, and is used for interlayer adhesion of multilayer printed boards and adhesion of surface metal foil, as well as for attaching protrusions for mounting semiconductor chips and one or more stages of electrode terminals around the protrusions. prepreg for adhesion between layers of multilayer printed boards, prepreg for adhesion of metal foil for metal foil-clad metal core laminates, prepreg for adhesion of metal plates for heat dissipation, flexible printed wiring boards, prepreg with semi-hardened metal foil It is suitably used for such purposes.

[Conventional technology and its problems]

It is known that a polyfunctional cyanate ester resin composition modified with a thermoplastic polyester resin can be used as a film as it is or as a prepreg based on fiber cloth such as glass cloth, quartz fiber cloth, aramid cloth, etc. (Unexamined Japanese Patent Publication 1986
-192779, 6O-233175). Although these have excellent adhesive strength and heat resistance, they are not necessarily sufficient for applications requiring lower dielectric constants, and even better electrical properties have been required.

Furthermore, fluororesin is a resin with excellent electrical properties such as a low dielectric constant, and porous films and sheets are also known. However, this had the drawback of poor adhesiveness.

[Means for solving problems]

The present invention was completed as a result of studies aimed at obtaining an adhesive prepreg that has excellent electrical properties such as dielectric constant, uniformity of thickness, ease of embedding printed wiring networks, and low resin flowability.

That is, the present invention provides (a) a polyfunctional cyanate ester resin composition containing two or more cyanato groups in the molecule;
b) A solution of a thermosetting resin composition containing a substantially amorphous thermoplastic saturated polyester resin as an essential component (c)
This adhesive prepreg is characterized in that it is impregnated into a stretched porous polytetrafluoroethylene resin sheet or film and dried to bring the resin component into a semi-cured state.

The configuration of the present invention will be explained below.

The resin component (a) used in the production of the adhesive prepreg of the present invention
) is a polyfunctional cyanate ester resin composition that contains a polyfunctional cyanate ester having a cyanato group, its prepolymer, etc. as essential components, and is a cyanato resin (Japanese Patent Publication No. 41-1928; -11712, 44-1222, DB-1,190,184, etc.), cyanate ester-maleimide resin, cyanate ester-
Maleimide-epoxy resin (Special Publication No. 54-30440,
52-31279, USP-4,110,364, etc.)
, cyanate ester-epoxy resin (Special Publication No. 46-41
112), etc.

Here, a preferable polyfunctional cyanate ester which is an essential component of component (a) has the following general formula (1)% formula%
(1) (In the formula, m is an integer of 2 or more and usually 5 or less, R is an aromatic organic group, and the cyanato group is bonded to the aromatic ring of the organic group) It is a compound that is To give a concrete example, 1゜3-
or 1,4-diallylbenzene, 1.3.5-) lycyanatobenzene, 1.3-, 1.4-, 1.6-, 1.
8-, 2.6- or 2°7-dicyanatonaphthalene, 1
．． 3.6-) lycyanatonaphthalene, 4.10” dicyanatobiphenyl, bis(4-dicyanatophenyl)methane, 2.2-bis(4-cyanatophenyl)propane,
2.2-bis(3,5-dichloro-4-cyanatophenyl)propane, 2,2-bis(3,5-cyflomo4-
Cyanatophenyl)propane, bis(4-cyanatophenyl)ether, bis(4-cyanatophenyl)thioether, bis(4-cyanatophenyl)sulfone, tris(4-cyanatophenyl)phosphite, tris(4-cyanatophenyl)propane,
-cyanatophenyl) phosphate, and cyanic acid esters obtained by the reaction of novolaks with cyanogen halides. In addition to these, the special public interest
8, 43-18468, 44-4791, 45
-11712, 46-41112, 47-2685
Cyanic acid esters described in No. 3 and JP-A-51-63149 can also be used.

Moreover, the above-mentioned polyfunctional cyanate ester can be used as a prepolymer. These prepolymers generally have a sym-triazine ring in the molecule, which is formed by trimerization of the cyanide groups in the cyanate ester. In the present invention, it is preferable to use the prepolymer having a number average molecular weight of 300 to 6.000.

The above polyfunctional cyanate ester is used as a composition containing a thermosetting monomer or prepolymer, if necessary. Such items include screws (4
- polyfunctional maleimide compounds such as maleimidophenyl)methane; polyfunctional (meth)acrylates, alkyl(
Poly(meth)acrylates such as meth)acrylate and epoxy(meth)acrylate; polyallyl compounds and their prepolymers such as diallyl phthalate, divinylbenzene, diallylbenzene, trialkenyl isocyanurate; dicyclopentadiene, cyclopentadiene and their Known resins such as prepolymers, phenolic resins, and epoxy resins are exemplified, and in particular, polyfunctional maleimide compounds, epoxy resins, alkyl (meth)acrylates, and alkyl-poly-(meth)acrylates can improve adhesive strength and It is preferably used from the viewpoint of improving workability.

The substantially non-crystalline thermoplastic saturated polyester resin of component (b) of the present invention is a polyester resin mainly composed of an aromatic or aliphatic dicarboxylic acid and an aliphatic or alicyclic diol or a prepolymer thereof. It is formed by condensation. In the present invention, the number average molecular weight calculated from the number of terminal functional groups is usually 1.500 to 25,000, preferably 5.00.
A value of 0 to 22,000 is preferable in terms of compatibility. Moreover, those having a hydroxyl value of 1 to 30 mg and 40,117 g are suitable. This means that when a substantially non-crystalline thermoplastic saturated polyester resin has an excess of free hydroxyl groups or carboxyl groups, these groups and the cyanato groups of component (a) gradually dissolve even at room temperature. This is because the composition will react and the storage stability of the composition will be poor. Furthermore, the lower the crystallinity, the better, and the types and usage ratios of the acid and alcohol components to be used are selected.

Examples of aromatic to aliphatic polycarboxylic acids include:
Terephthalic acid, isophthalic acid, malonic acid, succinic acid, adipic acid, pimelic acid, superric acid, azelaic acid, sepacic acid, lower alkyl esters and acid anhydrides thereof, and low molecular weight carboxyl group-terminated saturated polyester resins. Examples include thermal decomposition products.

In addition, examples of aliphatic to alicyclic polyols or prepolymers thereof include ethylene glycol, propylene glycol, 1.3-propanediol, 1.4-butanediol, 1.5-bentanediol, and 1゜6-hexanediol. , neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, polycaprolactone diol, 2.2-dimethylpropanediol, 2.2-bis(4-hydroxycyclohexyl)broha:/, 1. 4-dihydroxymethylcyclohe-1F-S7, trimethylolpropane, 1.2
．． Examples include 3-trihydroxypropane and tetramethylolmethane, and in order to make it non-crystalline, it is preferable to use one with low molecular toxicity.

As such a substantially non-crystalline thermoplastic saturated polyester resin, one commercially available from Nippon Gosei Chemical Industry Co., Ltd. under the trade name "Polyester" is suitable.

The blending ratio of component (a) and component (b) described above is not particularly limited, but usually component (a) is 30 to 95
(parts by weight, components, etc.) 70 to 5 parts by weight.

The method of mixing components (a) and (a) is not particularly limited, but
Usually, a method of preparing a solution of component (a) and mixing it with component (b) or a solution of component (b); a method of melting and mixing each component without a solvent and then preparing a solution; A resin composition is prepared in advance by a method such as a method of making a solvent-free liquid or paste composition using a reactive diluent among the components that can be used in combination, and a catalyst described later is added to this as necessary. Mixing method: The method of mixing using a catalyst or the like at the time of mixing as described above. Suitable organic solvents include methyl ethyl ketone, acetone, toluene,
Examples include xylene, trichloroethylene, dioxane, etc., and the concentration is selected depending on the amount of resin and viscosity required for impregnation, but usually 20 to 60% by weight is suitable.

The stretched porous tetrafluoroethylene resin sheet or film of component (c) of the present invention is, for example,
Examples include those manufactured by the method described in Japanese Patent No. 991, and usually have a thickness of 0.05 to 0.3 mm and a porosity of 40 to 40.
It has 97% fine open cells.

After impregnating the resin solution prepared above into a base material, which is a stretched porous polytetrafluoroethylene resin sheet or film (component (c)), the solvent was removed by drying at 120 to 170°C for 1 to 20 minutes. , uncured solvent-free, or so-called r[i-1-5ta J. The amount of resin in the adhesive prepreg is selected from a range of 30 to 80% by weight based on the total weight.

As described above, the adhesive prepreg obtained by impregnating and drying the resin composition containing the components (a) and (b) of the present invention as essential components can be cured by heating as it is, but a catalyst is used to accelerate the curing. Alternatively, a curing agent may be added.

Such compounds include organic peroxides such as benzoyl peroxide, lauroyl peroxide, caprylic peroxide, acetyl peroxide, parachlorobenzoyl peroxide, di-tert-butyl di-perphthalate; azobisnitrile; Azo compounds such as 2-methylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1
-benzyl-2-methylimidazole, 1-propyl-
2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1
-Imidazoles exemplified by cyanoethyl-2-ethyl-4-methylimidazole and 1-guanamineethyl-2-methylimidazole, as well as adducts of carboxylic acids or their anhydrides to these imidazoles; N , N-dimethylbenzylamine, N, N-dimethylaniline, N, N-dimethyltoluidine, NlN-
Dimethyl-p-anisidine, p-halogeno-N, N-dimethylaniline, 2-N-ditylanilinoethanol,
Tertiary amines such as tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, triethylenediamine, N, N, N', N'-tetramethylbutanediamine, N-methylpiperidine; phenol, Phenols such as xylenol, cresol, resorcin, catechol, phloroglycin; lead naphthenate, lead stearate, zinc naphthenate,
Zinc octylate, tin oleate, dibutyltin malate,
Organic metal salts such as manganese naphthenate, cobalt naphthenate, iron acetylacetonate; 5nC14, ZnCl2
, AlCl3; acid anhydrides such as maleic anhydride, phthalic anhydride, lauric anhydride, pyromellitic anhydride, trimellitic anhydride, hexahydrophthalic anhydride, hexahydrotrimellitic anhydride, hexahydropyromellitic anhydride Examples include things. In the present invention, the amount of the polymerization initiator and thermosetting catalyst to be added is sufficient within the range of the catalyst amount in a general sense, for example, an amount of 10 wt% or less, usually several % or less, based on the total composition. used.

The curing conditions for manufacturing sheets, plates, etc., adhesive structures, etc. by adhering to other substrates using the adhesive prepreg of the present invention vary depending on the type of curing agent, catalyst, composition components, etc. , usually selected within the range of 100 to 300°C. It is preferable to apply pressure during heat curing, generally speaking 0.1 to 100 kg/csl
, preferably 5 to 50 kg/C [+! be selected as appropriate within the range. In addition, for lamination molding, 100 mm 11 g
The following method of lamination molding in a substantially vacuum state is also suitable.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. Note that parts and percentages in Examples and Comparative Examples are parts by weight unless otherwise specified.

Example-1 2,2-bis(4-cyanatophenyl)propane 60
A prepolymer was obtained by preliminarily reacting a portion at 160° C. for 4 hours. This prepolymer is a substantially non-crystalline thermoplastic saturated polyester resin (trade name: Polyester-LP-03).
5. Manufactured by Nippon Gosei Kagaku Kogyo 01, number average molecule ffi 16,000 calculated from the number of terminal functional groups, hydroxyl value 6m
g KOII/g ) and 15 parts of bisphenol A type epoxy resin (product name: Epicote 828, Yuka Shell Epoxy Q ,
A solution with a concentration of 30% was prepared (referred to as FES (a)).

This face (a) has a thickness of 0.060 mm and a porosity of 68
% stretched porous tetrafluoroethylene resin film and heated at 150° C. for 5 minutes to obtain a prepreg with a resin content of 60% and a gelation time of 2.4 minutes (at 170° C.).

Place one prepreg obtained above on an aluminum plate with a thickness of 1.0 mm, and place a copper foil with a thickness of 35ρ on top of it.
Lamination molding was carried out under the conditions of 25 kg/Cnt at 70° C. for 2 hours to obtain a copper clad plate with a thickness of 1.095 m+n.

The peel strength of the copper foil of this copper clad board is 2.1 kg/cm
The soldering heat resistance was maintained at 300° C. for 2 minutes or more without any abnormality, and the surface resistance was 3×10′4Ω.

Example-2 In Example-1, the face (a) has a thickness of 0.090
It was impregnated into a stretched porous polytetrafluoroethylene resin film with a porosity of 68% and heated at 150°C for 5 minutes to reduce the amount of resin to 68%.
A prepreg with a gelation time of 1% and a gelation time of 2.1 minutes (at 170°C) was obtained.

A wiring network having IC chip connection terminals is formed on one side of a double-sided copper-clad glass cloth base epoxy resin laminate with a copper foil thickness of 35 JU and a thickness of 0.8 mm by photoetching, and the above prepreg is placed on this printed wiring board. 8m in place
Drill an m square hole, then place an 8 mm hole in a predetermined position on a single-sided copper-clad glass cloth base epoxy resin laminate with a thickness of 0.8 mm.
Align and overlap the pieces with holes in the corners, and apply pressure to 30
kg/co? , Heat curing was carried out at 170°C for 2 hours.

Next, through holes were made at predetermined positions in the obtained multilayer board, and I
A protective film was applied to the terminal portion for the C chip, and a through-hole plate was obtained by a known method.

The distance at which the resin seeped out from the prepreg into the 8m+n square holes of this multilayer board was 0.08 mm. Further, the soldering heat resistance was maintained at 300° C. for 60 seconds or more without any abnormality.

Example-3 2,2-bis(4-cyanatophenyl)propane 50
1 part and 5 parts of bis(4-maleimidophenyl)methane.
A prepolymer was prepared by pre-reacting at 60° C. for 2 hours. To this, 20 parts of the same polyester resin as in Example-1, bisphenol A type epoxy resin (trade name: Ebicoat 1
001, melting point 68°C, epoxy equivalent 450-500,
(manufactured by Yuka Shell Epoxy ■), 20 parts of reactive acrylonitrile-butadiene rubber containing terminal vinyl groups (trade name: VTBNX, viscosity 2.8 x 10'cPS at)
At 27°C, 5 parts of acrylic vinyl group 3.8%, acrylonitrile bond 16.2%, manufactured by Ube Industries G→) were added, dissolved and mixed in methyl ethyl ketone (hereinafter referred to as MEK) to make a solution with a concentration of 40% (Fes ).

To this phase (b), 0.0% zinc octylate was added as a catalyst.
04 parts were added and mixed uniformly, impregnated into a stretched porous fluorinated ethylene resin film with a thickness of 0.10 mm and a porosity of 68%, and heated at 140°C for 7 minutes to obtain a resin amount of 55% and a gelation time of 2. A prepreg was obtained for 5 minutes (at 170°C).

After forming a predetermined wiring network on one side of a fluorinated ethylene resin copper-clad laminate with a thickness of 0.8 mm using a known method, a surface treatment liquid for IJium-based fluororesin is applied. The surface was treated with

On this laminate, the prepreg obtained above and the copper foil with a thickness of 351 were stacked and laminated at 170°C and 30 kg/caf for 90 minutes, and a predetermined wiring network was formed at a predetermined position again. A multilayer shield plate with four inner layers and a copper foil outer layer was obtained by repeating the method of overlapping and laminating prepregs, and a multilayer printed board was produced by punching through holes and through-hole plating and etching using known methods.

The dielectric constant of the cured prepreg used was 2.8 (IMH
z), the dielectric loss tangent is 0.0050 (IMHz),
The soldering heat resistance of multilayer printed boards is 60 seconds or more (280℃)
Met.

[Operation and effects of the invention]

As is clear from the above detailed description and examples, the adhesive prepreg of the present invention has excellent adhesive strength, electrical properties, heat resistance, etc., has extremely small resin flow, and is suitable for multilayer lamination molding. The embeddability of metal foil for wiring is also excellent, and it is suitable for interlayer adhesion of multilayer printed boards, prepreg for adhesion of surface metal foil, convex parts for mounting semiconductor chips, and one or more stages of electrode terminals around the convex parts. Pre-preg for multi-layer adhesion of multi-layer printed boards, prepreg for adhesion of metal foil for metal-foil-clad metal-core laminates, prepreg for adhesion of metal plates for heat dissipation, flexible printed wiring boards, prepreg with semi-hardened metal foil It is suitably used for such purposes.

Claims (1)

[Claims] The essential components are (a) a polyfunctional cyanate ester resin composition containing two or more cyanato groups in the molecule, and (b) a substantially non-crystalline thermoplastic saturated polyester resin. (c) A stretched porous tetrafluoroethylene resin sheet or film is impregnated with a solution of a thermosetting resin composition, and dried to bring the resin component into a semi-cured state.