JPS61199689A - Substrate for printed circuit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a printed circuit board, and more specifically,
A new printed circuit that has excellent heat resistance, especially soldering heat resistance, can be used even at high temperatures, has high mechanical strength, allows thinning of the board, and has stable electrical properties. related to the board for use.

[Technical Background of the Invention and its Problems] Printed circuit boards have conventionally been made using the surface of a composite sheet made of a combination of a thermosetting resin such as an epoxy resin or a phenolic resin and a base material such as paper or glass fiber. A metal layer provided on the surface is used.

However, the handling of the above thermosetting resin (111
Sometimes a solvent is also used, which creates a problem of poor working environment, and furthermore, it takes a long time to cure the resin, which is not industrially practical.

In order to solve the problems of thermosetting resins as mentioned above,
Printed circuit boards using thermoplastic resins such as crosslinked polyethylene and polyphenyl sulfide in place of thermosetting resins have been proposed.

However, for example, since the heat distortion temperatures of the two thermoplastic resins mentioned above are 135°C and 2BO°C, respectively,
Poor solder heat resistance, making it difficult to use in high-temperature environments. As described above, even if a thermoplastic resin is used, its applications are considerably limited since printed circuit boards are often used in high-temperature environments.

[Object of the Invention] The present invention solves the above-mentioned problems, has excellent heat resistance, especially soldering heat resistance, can be used even at high temperatures, has high mechanical strength, and has a thin substrate. The purpose of the present invention is to provide a printed circuit board that is capable of providing stable electrical properties.

[Summary of the invention] The printed circuit board of the present invention is:

15 to 85% by weight of polycyanoaryl ether containing 80 mol% or more of repeating units represented by the following formula: and glass m
It is characterized by consisting of an insulating substrate which is a composite body with 15 to 85% by weight of fiber, and a metal layer provided on the surface of the insulating substrate.

First, the polycyanoaryl ether which is a component of the insulating substrate in the present invention contains 80 mol % or more of the edge-turning unit represented by the above formula (I).

The content of repeating units represented by formula (1) is 80 mol%
If it is less than 10%, the heat resistance and mechanical strength of the obtained insulating substrate will decrease.

In addition to the repeating unit represented by formula (I), the polycyanoaryl ether used in the present invention has the following formula: (wherein, Ar' is different from the 7-aryl group in formula (I). 20 mol% of at least one repeating unit represented by ) representing a divalent 7-aryl group
A copolymer containing the following may be used.

Ar' in formula (II) is H3 when the copolymer component of the repeating unit represented by formula (II) is 20
If the content exceeds mol%, the heat resistance and mechanical strength of the obtained insulating substrate will decrease.

This polycyanoaryl ether has a polystyrene-equivalent number average molecular weight of 20 as measured by high-temperature gel permeation chromatography at 135°C in a 70 mg/dJ1 solution using tomethylpyrrolidone as a solvent.
If the molecular weight is less than 20,000, the heat resistance will be insufficient,
This is because if it exceeds 00, it becomes difficult to form a composite with glass fiber, which will be described later. Preferably, the number average molecular weight is 2500
It is 0-7000G.

The polycyanoaryl resin described above is produced as follows.

That is, dihalogenobenzonitrile and any of the alkali metal salts of dihydric phenols are dissolved in a solvent such as N-methylpyrrolidone or sulfolane and reacted at a predetermined temperature, and then reacted with water or alcohol. All you have to do is process it.

When polycyanoaryl ether is used as a copolymer, two or more types of dihydric phenols may be used.

The blending amount of the polycyanoaryl ether in manufacturing the insulating substrate is 15 to 85% by weight. If the blending amount is 15% by weight without grooves, the polycyanoaryl ether will not be sufficiently dispersed in the gaps between glasses m and *, and if the blending amount is 15% by weight.
If it exceeds 9, sufficient heat resistance and mechanical strength cannot be obtained.

Next, - The glass fiber that is one of the constituent components of the insulating substrate may be of any type as long as it is normally used as a reinforcing material, and there are no particular limitations on its type or form as a reinforcing material. For example, the form may be chopped fiber, chopped fiber mat, continuous filament mat, woven fabric, etc., and a combination of these forms may be used.

The amount of glass fiber added to the insulating substrate is usually 15 to 80% by weight, preferably 20 to 70% by weight. If the blending amount is 15% by weight, the heat resistance and mechanical strength will be insufficient, and if it exceeds 85% by weight, it will be difficult to form a homogeneous composite with the polycyanoaryl ether. Become.

The method for manufacturing an insulating substrate made of a composite of the polycyanoaryl ether and the glass fiber includes: (1) a method of mixing and compression molding the polycyanoaryl ether and short glass fibers (chopped fibers); (2) A method of uniformly spreading polycyanoaryl ether powder or pellets onto a mat or fabric of long glass fibers and compression molding; (3) Extrusion molding, compression molding, etc. from polycyanoaryl ether pellets. This polycyanoaryl ether sheet is laminated with a long glass fiber mat or woven fabric and then compression molded.

(0 Examples include a method of appropriately combining methods (1), (2), and (3) above.

In all cases of (1), (2), and (3), known additives such as antioxidants, heat stabilizers, crystal nucleating agents, ultraviolet absorbers, and fillers are added to the polycyanoaryl ether. There is no problem in adding it appropriately.

Next, the constituent metals of the metal layer formed on the surface of the insulating substrate obtained by the above method are as follows.

Examples include copper, aluminum, nickel, and silver. These metals are usually used as metal foils when applied to printed circuit boards, but are not limited thereto; for example, they may be formed from a plating solution in the additive method described below.

Methods for forming the metal layer on the insulating substrate include: (1) a subtractive method in which the insulating substrate and the metal foil are bonded together using, for example, an adhesive, and then pattern etched according to a desired circuit pattern; (2) A stamping foil method in which metal foil punched in advance into a desired circuit pattern is laminated.

(3) Generally known methods such as the additive method of plating metal into a desired circuit pattern on an insulating substrate can be applied.

[Examples of the invention] Example 1 (1) Production volume of polycyanoaryl ether: 5! L
In an autoclave, add 1374 g of hydroquinone (1
, 25 mol), 2,8-dichlorobenzonitrile 2
15g (1.25 mol), potassium carbonate 207g (1
, 5 mol), sulfolane 2.5 Jl,) luene 1.5
Prepare JL at 180℃ in argon stream 1
．． 5 hours.

After the reaction was completed at 200° C. for 1.5 hours, a large amount of water was injected to obtain polycyanoaryl ether powder. The obtained powder was further washed with hot water and methanol, and then dried.

As a result, the yield of polymer was 280g (yield 100%
), and the number average molecular weight of the polymer was 44,000, and the M-position content was 100 mol%.

Regarding the thermal properties of this polymer, the glass transition temperature (g) was 180°C, the melting point (T) was 340°C, and the thermal decomposition onset temperature (Td) was 520°C (in air).

(2) Manufacture of printed circuit board The polycyanoaryl ether pellets described above are extrusion-molded, and the wall thickness is set to 0 so that the content of polycyanoaryl ether in the insulating board is the value shown in the table. Two 5-layer sheets (50 shoes x 50 Homaro) were manufactured.

Next, two sheets of the above-mentioned polycyanoaryl ether were used to create a glass continuous fiber mat (manufactured by Asahi Fiberglass Co., Ltd.: CSM) whose glass fiber content in the insulating substrate was set to the value shown in the table.

111800) One sheet was sandwiched.

Then, the whole was heated to 390°C, 50mm x 5Qm.
The material was supplied to an s+ flat plate mold and heated and compressed at a pressure of 6 kg/cvdG for 4 minutes, then transferred to a cooling press set at 250°C and cooled for 5 minutes under a pressure of 30 kg/dG.

As a result, a composite sheet with a wall thickness of 1.1 cm was obtained.

Next, this composite sheet is used as an insulating substrate, and after bonding this insulating substrate and electrolytic steel foil with an epoxy resin adhesive,
By applying heat and pressure treatment, a printed circuit board in which the copper foil and the insulating board were integrated was obtained.

Regarding the obtained printed circuit board, the heat distortion temperature (A
(based on STN-DB4B).

Bending strength (according to ASTN-0790).

Peel strength of copper foil (according to JIS-6481).

Dielectric constant and dielectric loss tangent (based on ASTN-0150).

Measurement frequency 10” Hz,) was measured.

Example 2 Polycyanoaryl ether has 100 mol% of repeating units starting from 2,6-cyclopenzonitrile and 4,4'-biphenol, and has a number average molecular weight of 4.
0000, in terms of thermal properties Tg 220℃, T
A printed circuit board was manufactured in the same manner as in Example 1, except that polycyanoaryl ether having m of 360°C and Td of 540°C was used, and measurements were conducted in the same manner.

Example 3 A polycyanoaryl ether containing 100 mol% of repeating units of 2,6-cyclobenzonitrile and 2,7-hydroxynaphthalene, a number average molecular weight of 38,000, and a thermal property of Tg 215. ℃.

A printed circuit board was manufactured in the same manner as in Example 1, except that polycyanoaryl ether having a Ts of 340° C. and 505° C. was used and the temperature during press molding was 400° C., and measurements were conducted in the same manner.

Example 4 A printed circuit board was produced in the same manner as in Example 1, except that the content of glass m-fiber was made slightly more than twice that in Example 1, and measurements were performed in the same manner.

Comparative Example 1 Example 1 except that the glass fiber content was 10% by weight
A printed circuit board was manufactured in the same manner as above, and measurements were performed in the same manner.

Comparative Example 2 A printed circuit board was manufactured in the same manner as in Example 1, except that a thermoplastic resin, polyether ether ketone (manufactured by Imperial Chemical Industries), was used as the resin component, and measurements were performed in the same manner.

The above results are summarized in the table.

[9. Effect of light] As is clear from the examples of the invention, the uninvented printed circuit board is made of polyether, which has been known to have the best heat resistance and soldering heat resistance. It has the same heat resistance as a substrate using ether ketone,
Moreover, the mechanical strength is superior to that, and therefore, the substrate can be made thinner and lighter and smaller. Such excellent heat resistance allows printed circuit boards to be used at high temperatures.

As described above, the printed circuit board of the present invention has heat resistance, soldering heat resistance, mechanical strength when used at high temperatures, 'N,
Due to its excellent chemical properties, it is useful for home appliances, communication devices, measuring instruments, etc.
Its industrial value is great.

Claims (1)

[Claims] The following formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, Ar is ▲There are mathematical formulas, chemical formulas, tables, etc.▼,
▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲Mathematical formulas, chemical formulas,
There are tables, etc. ▼ Represents one of the following. ) An insulating substrate that is a composite of 15 to 85% by weight of polycyanoaryl ether containing 80 mol% or more of the repeating unit represented by the formula and 15 to 85% by weight of glass fiber, and a metal provided on the surface of the insulating substrate. A printed circuit board characterized by comprising layers.