JPH04348096A - Thermoplastic electrical insulating board - Google Patents

Abstract

PURPOSE:To provide a novel thermoplastic electrical insulating board excellent in heat resistance, fire retardancy, dimensional stability, etc., being indispensable for responding to the problem of mounting parts on a printed wiring board in high density. CONSTITUTION:This is a thermoplastic electrical insulating base material for a printed wiring board which is made by molding a composition which contains 51-500wt. portion a Wallastonite alone or both Wallastonite and mica to 100wt. portion of polyphenylene sulfide resin.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel thermoplastic electrically insulating substrate that is used as a printed wiring board and has excellent heat resistance, flame resistance, dimensional stability, etc.

0002

[Prior Art] Conventionally, insulating substrates for printed wiring boards have been widely used, which are formed by combining thermosetting resins such as epoxy resins and phenolic resins with reinforcing materials such as paper and glass fibers. It is being A metal layer is provided on such an insulating base material to form a laminate, and as a printed wiring board, holes are bored as necessary to form a non-through-hole plated printed wiring board, a through-hole plated printed wiring board, and a multilayer printed wiring board. It is considered to be a board etc. however,
The manufacturing process of printed wiring boards incorporates the drilling process as described above, and is accompanied by machining work, making the manufacturing process complicated. In addition, the recent trend in the electrical equipment, telecommunications equipment, and electronic equipment industries is to make these equipment lighter, thinner, shorter, and lower in cost.As a result, printed wiring boards are also required to be mounted in higher density, and are highly heat resistant. Further improvements in physical properties such as flame resistance and dimensional stability are required. However, the above-mentioned substrates are no longer able to fully meet such demands.

0003

[Problem to be solved by the invention] The purpose is to develop a new thermoplastic material that has excellent heat resistance, flame retardance, and dimensional stability, which are essential for meeting the challenge of high-density mounting of printed wiring boards. The purpose of the present invention is to provide an electrically insulating substrate.

0004

[Means for Solving the Problems] The present invention provides that, for 100 parts by weight of polyphenylene sulfide resin (PPS),
A thermoplastic electrical insulating base material for printed wiring boards formed by molding a composition containing 51 to 500 parts by weight of wollastonite, or a total of 51 parts by weight of wollastonite and mica based on 100 parts by weight of PPS. This is a thermoplastic electrically insulating base material for a printed wiring board formed by molding a composition containing ~500 parts by weight.

In the present invention, PPS has the general formula (-
Those containing 70 mol% or more of the structural unit represented by C6H5-S-)n are preferred; if the amount is less than 70 mol%, it is difficult to obtain a composition with excellent properties. A suitable method for polymerizing this polymer is a method in which sodium sulfide and p-dichlorobenzene are reacted in an amide solvent such as N-methylpyrrolidrine or dimethylacetamide, or a sulfone solvent such as sulfolane.

At this time, in order to adjust the degree of polymerization, an alkali metal salt of carboxylic acid or sulfonic acid, or an alkali hydroxide, an alkali metal carbonate, or an alkaline earth metal oxide is added. If it is less than 30 mol% as a copolymerization component, meta bonds, ortho bonds, ether bonds, sulfone bonds,
Biphenyl bond, substituted phenylene sulfide bond (here, substituents include alkyl group, nitro group, phenyl group,
Alkoxy groups, carboxylic acid groups, or metal bases of carboxylic acids), trifunctional bonds, etc. may be included as long as they do not significantly affect the crystallinity of the polymer, but preferably the copolymerization component is 10 mol% or less. good. Regarding the melt viscosity, a low viscosity one is preferable since it is highly filled with wollastonite or wollastonite and mica.

On the other hand, wollastonite is a naturally occurring calcium metasilicate, a white acicular mineral with a chemical composition represented by CaSiO8, with a specific gravity of 2.9 and a melting point of 15.
It is at 40°C. More specifically, depending on the crystal structure, α
There are two types: the alpha type and the beta type, and the alpha type is often granular or powder-like, while the beta type is said to be more needle-like or long columnar. In addition, the composition of the present invention is generally prepared into various sizes by pulverization and commercially available.
It is preferable that 0% or more of the particles have a size of 300 mesh or less in order to maintain good mechanical strength and surface smoothness of the molded product. Furthermore, as the mica, muscovite mica (muscovite) and phlogopite mica (phlogopite) are preferably used, and the aspect ratio as a factor specifying the shape is 3.
A value of 0 or more is preferably used to maintain good mechanical strength and dimensional stability such as warpage. Here, the aspect ratio is expressed as average diameter/average thickness. Moreover, wollastonite and mica may be used without surface treatment, but those that have been surface treated with various surface treatment agents can also be used. Surface treatment agents include waxes such as low molecular weight polyethylene and low molecular weight polypropylene, saturated higher fatty acids such as stearic acid and palmitic acid, saturated higher fatty acid metal salts such as magnesium stearate, unsaturated higher fatty acids such as oleic acid, and oleic acid. unsaturated higher fatty acid metal salts such as magnesium,
Titanate coupling agents such as isopropyl triisostearic titanate, silane coupling agents, various surfactants such as polyoxyethylene alkyl ether, etc. can be used.

[0008] The blending ratio of wollastonite or wollastonite and mica is preferably 51 to 500 parts by weight, more preferably 100 to 3 parts by weight, based on PPS.
00 parts by weight. Here, if the amount exceeds 500 parts by weight, molding becomes difficult and is therefore not appropriate. On the other hand, if the amount is less than 50 parts by weight, the insulating base material formed from such a composition will have low dimensional accuracy and large warpage, making it impossible to achieve the intended purpose.

The composition of the present invention is prepared in advance as a molding material in any form, such as pellets, so that it can be made suitable for molding an insulating substrate. That is, as a kneading method, a usual known method is applied, but generally the mixture is melt-kneaded using an extrusion kneader and then pelletized. In addition,
Appropriate amounts of other components such as pigments, heat stabilizers, antioxidants, weathering agents, crystallization promoters, lubricants, etc. may be added to the composition of the present invention.

[0010] The pellet-shaped molded material thus obtained is processed by a commonly used thermoplastic resin molding machine,
For example, it is molded into a desired shape as an insulating base material using an injection molding machine, a compression molding machine, an injection compression molding machine, an extrusion molding machine, or the like. The molding conditions in the molding method are not particularly limited, and the molding is carried out under normal molding conditions. In this way, a desired thermoplastic electrically insulating substrate for printed circuit boards can be obtained.

Various methods have been proposed for forming a conductive circuit on the thus obtained thermoplastic electrically insulating substrate of the present invention, examples of which include an additive method and a semi-additive method. There are also methods of forming a circuit using conductive paste using a screen printer, and methods of printing a circuit pattern on a film using conductive paste and then transfer-printing the circuit pattern.

Next, the present invention will be explained in more detail with reference to Examples, but it is needless to say that the present invention is not limited to these Examples.

[0013]

【Example】

<<Example 1>> 300 parts by weight of wollastonite (manufactured by Hayashi Kasei) was melt-kneaded with 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480),
The composition was molded using an injection molding machine at a cylinder temperature of 350°C.
It was molded at an injection pressure of 1000 kg/cm2 and a mold temperature of 150°C to a thickness of 1.6 mm as shown in Figure 1.
A plate-shaped molded product of 0 cm x 30 cm was obtained. One sheet of adhesive copper foil with a thickness of 35 μm was placed on each side of the plate-shaped molded product, and then heated and pressed at 145°C for 30 minutes at a molding pressure of 20 kg/cm2 to obtain a metal-clad plate-shaped molded product. Drill holes (a, b, c) of 1 mm diameter a-b in the metal-clad plate-like molded product as shown in Figure 1.
Openings were made at three locations: 25 cm between b and c, and 25 cm between b and c. Further etching was performed to form a circuit on the surface to obtain a printed wiring board.

<<Example 2>> 300 parts by weight of wollastonite (manufactured by Hayashi Kasei) was melt-kneaded with 100 parts by weight of high-viscosity PPS (Toray Phillips Petroleum Co., Ltd. product number E0780), and the composition was injected. A plate-shaped molded product similar to that of Example 1 was obtained by molding using a molding machine at a cylinder temperature of 350°C, an injection pressure of 1500 kg/cm2, and a mold temperature of 150°C. After placing one piece of adhesive copper foil with a thickness of 35 μm on each side of the plate-shaped molded product, a molding pressure of 20 kg/
cm2, heated and pressed at 145° C. for 30 minutes to obtain a metal clad plate-like molded product, which was further etched to form a circuit on the surface to obtain a printed wiring board.

<<Example 3>> 100 parts by weight of PPS (product number E2480, manufactured by Toray Phillips Petroleum Co., Ltd.) was melt-kneaded with 100 parts by weight of wollastonite (manufactured by Hayashi Kasei), and the composition was molded into an injection molding machine. cylinder temperature 3
50℃, injection pressure 800kg/cm2, mold temperature 15
A plate-shaped molded product similar to that of Example 1 was obtained by molding at 0°C. After placing one piece of adhesive copper foil with a thickness of 35 μm on each side of the plate-shaped molded product, a molding pressure of 20 kg/cm2,
The product was heated and pressed at 145° C. for 30 minutes to obtain a metal-clad plate-like molded product, and further etched to form a circuit on the surface to obtain a printed wiring board.

<<Example 4>> Aminosilane surface-treated wollastonite (manufactured by Hayashi Kasei) to 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480)
300 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 1000 kg/c.
m2 and a mold temperature of 150° C. to obtain a plate-shaped molded product similar to that in Example 1. Thickness 3 on both sides of the plate-shaped molded product
After placing one piece of 5 μm adhesive copper foil on each sheet, heat and press at 145°C for 30 minutes at a molding pressure of 20 kg/cm2 to obtain a metal clad plate molded product, which was further etched to form a circuit on the surface. A printed wiring board was obtained.

<<Example 5>> 300 parts by weight of wollastonite (manufactured by Hayashi Kasei) was melt-kneaded with 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480), and the composition was put into an injection molding machine. cylinder temperature 3
50℃, injection pressure 1000kg/cm2, mold temperature 1
A plate-shaped molded product similar to that of Example 1 was obtained by molding at 50°C. The plate-shaped molded product was further heat-treated at 145° C. for 120 minutes, and then required circuits were formed on both sides of the plate-shaped molded product with conductive paste using a screen printer to obtain a printed wiring board.

<Comparative Example 1> 50 parts by weight of wollastonite (manufactured by Hayashi Kasei) was melt-kneaded with 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480), and the composition was put into an injection molding machine. cylinder temperature 35
0℃, injection pressure 800kg/cm2, mold temperature 150℃
A plate-shaped molded product similar to that of Example 1 was obtained by molding under the following conditions. After placing one piece of adhesive copper foil with a thickness of 35 μm on each side of the plate-shaped molded product, a molding pressure of 20 kg/cm2, 14
The product was heated and pressed at 5° C. for 30 minutes to obtain a metal clad plate-like molded product, and further etched to form a circuit on the surface to obtain a printed wiring board.

Comparative Example 2 Glass cloth base epoxy resin copper clad laminate (JIS-C6484, GE
A plate-shaped molded product of 30 cm x 30 cm was obtained from the 2F compatible product), holes were made as shown in FIG. 1, and a circuit was formed on the surface by etching to obtain a printed wiring board.

<<Example 6>> 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480), 200 parts by weight of wollastonite (manufactured by Hayashi Kasei), mica (manufactured by Kuraray, product number 200HK)
) 100 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 1000 kg/
cm 2 and molded at a mold temperature of 150° C. to obtain a plate-shaped molded product having a thickness of 1.6 mm and a size of 30 cm×30 cm as shown in FIG. After placing one piece of adhesive copper foil with a thickness of 35 μm on each side of the plate-shaped molded product, a molding pressure of 20 kg was applied.
/cm2 at 145° C. for 30 minutes to obtain a metal clad plate-like molded product, holes were made in the same manner as in Example 1, and further etching was performed to form a circuit on the surface to obtain a printed wiring board.

<<Example 7>> 100 parts by weight of PPS (product number E2480, manufactured by Toray Phillips Petroleum Co., Ltd.), 100 parts by weight of wollastonite (manufactured by Hayashi Kasei), mica (product number 200HK, manufactured by Kuraray)
) 200 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 1500 kg/
Example 6 by molding at a mold temperature of 150°C.
A plate-shaped molded product similar to that was obtained. One piece of adhesive copper foil with a thickness of 35 μm was placed on each side of the plate-shaped molded product, and then heated and pressed at a molding pressure of 20 kg/cm2 and 145°C for 30 minutes to obtain a metal-clad plate-shaped molded product. A printed wiring board was obtained by etching and forming a circuit on the surface.

<<Example 8>> 50 parts by weight of wollastonite (manufactured by Hayashi Kasei), mica (Susolite mica, product number 200HK, manufactured by Kuraray) per 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480)
50 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 800 kg/cm.
In Example 2, molding was performed at a mold temperature of 150° C. to obtain a plate-shaped molded product similar to that in Example 6. Thickness 35 on both sides of the plate-shaped molded product
After disposing one μm adhesive copper foil on each sheet, heat and press at 145°C for 30 minutes at a molding pressure of 20 kg/cm2 to obtain a metal-clad plate-like molded product, which was further etched to form a circuit on the surface. A printed wiring board was obtained.

<<Example 9>> 200 parts by weight of aminosilane surface-treated wollastonite (manufactured by Tsuchiya Kaolin Industries), aminosilane surface-treated mica (manufactured by Kuraray) to 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480) Susolite mica part number 200KI
) 100 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 1000 kg/
Example 6 by molding at a mold temperature of 150°C.
A plate-shaped molded product similar to that was obtained. One piece of adhesive copper foil with a thickness of 35 μm was placed on each side of the plate-shaped molded product, and then heated and pressed at a molding pressure of 20 kg/cm2 and 145°C for 30 minutes to obtain a metal-clad plate-shaped molded product. A printed wiring board was obtained by etching and forming a circuit on the surface.

<<Example 10>> 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480), 200 parts by weight of wollastonite (manufactured by Hayashi Kasei), mica (Susolite mica, product number 20, manufactured by Kuraray)
0HK) was melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 1000°C.
kg/cm 2 and a mold temperature of 150° C. to obtain a plate-shaped molded product similar to that in Example 6. The plate-shaped molded product was further heat-treated at 145° C. for 120 minutes, and then required circuits were formed on both sides of the plate-shaped molded product with conductive paste using a screen printer to obtain a printed wiring board.

<<Comparative Example 3>> 30 parts by weight of wollastonite (manufactured by Hayashi Kasei), mica (Susolite Mica, product number 200HK, manufactured by Kuraray) per 100 parts by weight of PPS (manufactured by Toray Phillips Petroleum Co., Ltd., product number E2480)
20 parts by weight were melt-kneaded, and the composition was molded using an injection molding machine at a cylinder temperature of 350°C and an injection pressure of 800 kg/cm2.
Then, molding was performed at a mold temperature of 150° C. to obtain a plate-shaped molded product similar to that in Example 6. Thickness 35μ on both sides of the plate-shaped molded product
After arranging one adhesive copper foil of m each, the molding pressure was 2.
The product was heated and pressed at 0 kg/cm2 and 145° C. for 30 minutes to obtain a metal-clad plate-like molded product, and further etched to form a circuit on the surface to obtain a printed wiring board.

Comparative Example 4 Glass cloth base epoxy resin copper clad laminate (JIS C6484, G
A plate-shaped molded product of 30 cm x 30 cm was obtained from the E2F compliant product, a hole was made as shown in FIG. 1, and a circuit was formed on the surface by etching to obtain a printed wiring board.

The physical properties of the printed wiring boards obtained in each of the above examples are shown in Tables 1 and 2 in comparison with those of conventional copper-clad printed wiring boards. The test method is shown in Table 3.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

Effects of the Invention As shown in the table, the electrically insulating substrate of the present invention has the synergistic properties of PPS resin and wollastonite or wollastonite and mica contained in the resin structure, and is superior to conventional glass. Compared to fabric-based epoxy resin copper-clad laminates, it can better respond to the trend toward smaller, lighter, thinner, and lower cost electronic and electrical equipment.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating a plate-shaped molded product in an embodiment of the present invention.

Claims (2)

[Claims] [Claim 1] Polyphenylene sulfide resin 10
1. A thermoplastic electrically insulating substrate formed by molding a composition containing 51 to 500 parts by weight of wollastonite. [Claim 2] Polyphenylene sulfide resin 10
A thermoplastic electric insulating substrate formed by molding a composition containing 51 to 500 parts by weight of wollastonite and mica based on 0 parts by weight.