JPS63187683A - Insulating substrate for printed board - 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 [Industrial Field of Application] The present invention relates to an insulating base material for printed circuit boards that has excellent heat resistance and mechanical strength and is used in the electrical and electronic fields.

[Prior Art] Conventionally, laminates in which metal scraps such as copper are provided on an insulating base material have been used as rigid printed circuit boards, flexible printed circuit boards,
Used in film carrier tapes, etc. In such laminates, rigid prints (compounds of thermosetting resins such as epoxy resins and phenol resins and reinforcing materials such as paper and glass fibers are widely used as insulating base materials for plates).

Rigid printed circuit boards made of laminates with metal layers provided on insulating substrates, such as non-through-hole plated printed circuit boards, through-hole plated printed circuit boards, and multilayer printed circuit boards, have holes drilled as necessary. The drilling step M1 is included in the manufacturing process of the board, and the process is complicated because it involves mechanical work. Pre-drilling the insulating substrate is therefore advantageous in terms of simplifying the process, and in this case, the use of thermoplastic resin allows the substrate to be injection molded.

1. The manufacturing process for printed circuit boards usually involves pattern formation, plating, etching, resist removal, drilling, etc., and the insulating base material is required to have good plating adhesion during plating. In addition, high heat resistance is required for the glue-flow type with solder connection, and high heat resistance and thermal stability are required for cases where the temperature is locally high due to wire bonding, etc. However, conventional insulating base materials made of composites of epoxy resins, phenolic resins, paper, glass fibers, etc. have poor heat resistance and ice cutting properties, and are said to cause a decline in dielectric properties at high temperatures, for example, above 150°C. There's a problem. Furthermore, since ITlt smear properties are correlated with the glass transition temperature (Tg) of the resin, materials with a high Tg are required.

In addition to the characteristics required for printed circuit boards and their insulating base materials, there are also recent demands for high-density ultra-multilayer boards and high heat resistance as electronic devices become more densely packaged. Polyimide, triazine, and other resins have been considered; for example, a nonconductive printed circuit board made of a heat-resistant thermoplastic selected from polyphenylene oxide, fosophenylene sulfide, polyether sulfone, and polyimide has been patented in U.S. Patent No. No. 4281038.

[Problems to be solved by the invention] The heat-resistant thermoplastic resins exemplified above have heat resistance and are relatively stable in soldering, etc., but in plating processing, they are resistant to etching solutions. There is a problem that sufficient adhesion of plating cannot be obtained due to high chemical resistance.

The present invention was made in view of the above-mentioned problems, and as a result of various studies and examinations on insulating base materials for printed circuit boards, the present invention was developed as a thermoplastic resin by the present inventors in Japanese Patent Application Laid-Open No.
We have discovered that the aromatic polythioethersulfone polymers disclosed in JP-A No. 72020, JP-A-61-76523, and JP-A-61-168629 are suitable, and have completed the present invention. It is something that

1.Uninvented, it has good adhesion during plating and soldering as a printed circuit board insulating base material.
The object of the present invention is to provide a new insulating base material for printed circuit boards that has adhesion properties, high heat resistance, and thermal stability.

[Means for Solving the Problems] That is, the present invention provides a compound selected from the following general formula (I), in which R1 to R7 represent hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, and are the same or different. You can stay here〈;a
-e is an integer of 0 to 4, f, and g are integers of 0 to 3, which may be the same or different; Y is a single bond, -0-, -S-, -9O
2-, -C-.

selected from -〇-; R represents hydrogen or a hydrocarbon group having 1 to 6 carbon atoms; m and n satisfy the range O≦m7m+n<1. When m=o, it is a polythioethersulfone homopolymer. ) An insulating base material for a printed circuit board is provided by molding an aromatic polythioethersulfone polymer represented by the following formula or a composition comprising the polymer and an inorganic filler.

In the present invention, the aromatic polythioether sulfone polymer represented by the general formula (1) is disclosed in Japanese Patent Application Laid-open Nos. 61-72020 and 6
Publication No. 1-76523 and Japanese Unexamined Patent Publication No. 168629/1986
This thermoplastic resin has excellent mechanical properties at high temperatures and can be obtained by the method disclosed in the above publication.

Therefore, in the aromatic polythioethersulfone polymer represented by the general formula (I), m is not O, and the ratio of m and n is m: n = 1: 20 to 2.
0:1 is preferable. Furthermore, in view of the properties as a copolymer, moldability, etc., preferably m:n=1:
10-15:1, particularly preferably m:n=1:4-10
:1 copolymer. The degree of polymerization of the aromatic polythioether sulfone polymer is phenol/1.1, 2.
The logarithmic viscosity ηinh measured at 30° C. for a solution of 0.5 g/dle using 2-tetrachloroethane-372 (weight ratio) as a solvent is usually preferably 0.1 to 1.5. Even more preferably, the above-mentioned logarithmic viscosity ηinh is from 0.1 to 1.3, particularly preferably from 0.1 to 1.0.

The insulating base material for printed circuit boards of the present invention is formed by molding an aromatic polythioethersulfone polymer alone or a composition comprising the aromatic polythioethersulfone polymer and an inorganic filler, but the latter is more preferable. It is. In a composition comprising an aromatic polythioethersulfone polymer and an inorganic filler, the inorganic filler is preferably in the form of fibers, fine particles, or powder. Here, as the fibrous material, for example, glass fiber, carbon fiber, potassium titanate ill ff1
Examples include l.

In addition, examples of fine particles or powders include silica, quartz, titanium oxide, antimony trioxide, iron oxide,
Magnesium oxide, zinc oxide, aluminum oxide, barium sulfate, calcium sulfate, calcium carbonate, magnesium carbonate, dolomite, calcium silicate, aluminum hydroxide, magnesium hydroxide, talc, kaolin wollastonite, clay, mica, graphite and glass Examples include peas. Such inorganic fillers are not limited to one type, and several types may be used in combination, and in the case of fibrous materials, the surface thereof may be treated with a surface treatment agent or the like. In such an inorganic filler,
An insulating base material formed by molding a composition containing an appropriate amount of fibrous material, particularly glass fiber, has significantly improved mechanical strength. Blending inorganic filler, 15 is O~5 Q ffi
if%, preferably 10 to 35% of the hair amount.

The aromatic polythioether sulfone polymer or the composition comprising the aromatic polythioether sulfone polymer and the inorganic filler may contain a lubricant that imparts improved properties.
], and appropriate amounts of stabilizers, anti-oxidizing agents, flame retardants, pigments, and other components may be added as desired.

The aggregate alone or the composition is prepared in advance into a molding material of the form 5E, such as a pellet, so as to be suitable for molding an insulating substrate. The method for producing 31 as a composition is carried out by a conventional mixing or kneading method. For example, the premix is mechanically mixed uniformly using a Henschel mixer, a tumbler mixer, a V-type mixer, etc. as a mixer used for mixing powdery materials. Next, this premix is put into a screw mixer with a wide shaft or two screws, melted and kneaded under high-temperature heating of 300 to 400°C, extruded into strands, cooled, and molded into pellets with a pelletizer. Use as wood.

The pellet-shaped molded material obtained in this way is usually
It is molded into a desired shape using a widely used thermoplastic resin molding machine, such as an injection molding machine, a compression molding machine, or an extrusion molding machine. Naturally, it is processed to provide holes necessary for the insulating base material. The molding conditions in the molding method are not particularly limited, and the molding is carried out under normal molding conditions. In this way, an insulating base material for a printed circuit board having a desired shape can be obtained.

The thus obtained insulating base material for a printed circuit board of the present invention can be made into a non-through-hole plated printed circuit board, a through-hole plated printed circuit board, or a multilayer printed circuit board by a conventional method for producing a rigid printed circuit board.

[Example] Example 1 4.4′-Dichlorodiphenylsulfone and sodium sulfide were added to a precursor obtained by reacting 4.4′-dichlorodiphenylsulfone, bisphenol A, and thorium hydroxide. In this way, an aromatic pj,l thioether sulfone polymer represented by the following formula [A] was obtained.

(For 314n, refer to the above-mentioned Japanese Patent Application Laid-Open No. 168629/1983).

(m/n=1/I, η1nh=0.50; 7!nor/1,1,2.2-tetrachloroethane=3/2(
Weight ratio), 30°CO, 5g/d I, Nll+ constant.

) This polymer was rotated at 50 screw rotations using a twin-screw extruder in different directions.
Extruded pellets were formed at revolutions/min. Next, the obtained pellets were molded into a cylinder at a temperature of 340° using an injection molding machine.
A test piece was obtained by molding under the conditions of C11000 kg/co+2 and a mold temperature of 120°C. The physical properties of this test were measured and the results are shown in Table 1.

In addition, in the physical property measurement method, plating adhesion and solder adhesion are based on JIS C-5012, and for plating adhesion, the presence or absence of a plating film that adheres to the tape side is visually observed. The strength was determined by etching with a chromic acid solution (Cr033, sulfuric acid: 10.5%, water: 30.5% by weight), followed by electroless plating.

Example 2 In Example 1, instead of bisphenol A, 4.4
A copolymer of the following formula [B] was produced in a similar manner using '-dihydroxydiphenyl.

(m/n = l/I, 771nh = 0.50) This copolymer was made into a berent in the same manner as in Example 1, and was first molded to obtain a test piece as an insulating base material, and the physical properties were measured. did. The results are shown in Table 1.

Examples 3 to 4 Copolymers of the following formulas [C] and [D] were produced in the same manner as in Example 2.

These copolymers were pelletized in the same manner as in Example 1 to obtain test pieces as insulating base materials, and their physical properties were determined. The results are shown in Table 1.

Examples 5 to 8 The respective aromatic polythioethersulfone polymers in Examples 1 to 4 were blended at 70% by weight and glass fibers at 30% by weight, and mixed and dispersed for 3 minutes in a V-type mixer. A premix was obtained. This premix was used in Example 1.
It was pelletized in the same manner as above, and then molded to obtain a test piece as an insulating base material, and its physical properties were measured. This result: f
Shown in Table S1.

Example 9 In Example 2, the composition components were 70 tons of copolymer,
A preliminary mixture was obtained by blending 15% by weight of glass fiber and 15% by weight of calcium silicate, and mixing and dispersing the mixture for 25 minutes using a V-type mixer.

This premix was pelletized in the same manner as in Example 1, and then molded to obtain a test piece as an insulating base material, and its physical properties were measured. The results are shown in Table 1.

Example 10 After electroless plating of copper was applied to the test piece obtained in Example 9 using a predetermined method, reflow soldering was performed using a device, but soldering was completed without copper peeling off from the board. was possible.

Comparative Example 1 A test piece was obtained by molding in the same manner as in Example 1, except that an aromatic polyether sulfone represented by the following formula [E] was used, and the physical properties were measured. The results are shown in Table 2.

Comparative Example 2 A test piece was obtained by molding in the same manner as in Example 1, except that an aromatic polyetherimide polymer represented by the following formula [F] was used, and the physical properties were measured. The results are shown in Table 2.

[Effects of the invention] [1] The insulating base material for printed circuit boards is formed by molding a composition made of an aromatic polythioethersulfone polymer, which is a thermoplastic and viscous resin with excellent heat resistance. from,
It has extremely excellent heat resistance as well as mechanical properties. Conventionally, insulating base materials made of heat-resistant resin have been proposed, but problems were recognized with respect to plating adhesion and solder adhesion, which are essential properties for printed boards. These drawbacks have been completely eliminated, and the product has the advantage of having extremely good plating adhesion and soldering 7i properties, as well as excellent durability.

Claims (2)

[Claims] (1) The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, Ar in the formula ▲There are mathematical formulas, chemical formulas, tables, etc.)
, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ may be the same or different; a to e are integers of 0 to 4, f and g are integers of 0 to 3, and may be the same or different; Y is a single bond, -O-, -S-, -SO_2- ,▲
There are mathematical formulas, chemical formulas, tables, etc. ▼▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ Selected from: R represents hydrogen, a hydrocarbon group having 1 to 6 carbon atoms: m, n is 0≦m/m+n<1 When m=0, it is a polythioethersulfone homopolymer. ) An insulating base material for a printed circuit board formed by molding an aromatic polythioethersulfone polymer represented by the following formula or a composition comprising the polymer and an inorganic filler. (2) The insulating base material for a printed circuit board according to claim 1, wherein the printed circuit board is a rigid printed circuit board.