JPH0857968A - Laminate for high frequency circuit - Google Patents

Abstract

PURPOSE: To improve the through-hole plating property of a laminate for a high frequency circuit obtained by using a sintered sheet obtained by sintering a sheet shaped from a plastic powder as a dielectric layer and laminating a cured curable resin impregnated reinforcing layer on the single surface or both surfaces of the dielectric layer and further providing a metal conductor layer on the reinforcing layer. CONSTITUTION: A sintered sheet obtained by sintering a mixture consisting of a plastic powder and a plating catalyst is used as a dielectric layer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated plate for electronic equipment, and more particularly to a laminated plate used in a high frequency range.

[0002]

2. Description of the Related Art In recent years, with the rapid development of communication systems, frequencies used in the electronic industry, communication industry, computer industry, etc. are gradually shifting to high frequency bands. In the high frequency band, a decrease in signal speed and a loss in signal quality have a great influence on the performance of the equipment. Therefore, a laminated board for a printed circuit is required in which a decrease in signal speed and a loss in signal quality are small. Therefore, a material having a low relative permittivity and a low dielectric loss tangent is used for the high frequency circuit laminate.

As a laminated plate having a low relative permittivity and a low dielectric loss tangent, a sintered sheet obtained by shaping plastic powder into a sheet and sintering is used as a dielectric layer 1, and cured on both sides or one side thereof. There is known a high-frequency circuit laminated plate in which a functional resin-impregnated reinforcing layer 2 is laminated and a metal conductor layer 3 is further provided (see FIG. 1).

[0004]

However, this laminated board for high-frequency circuits has a drawback that through-hole plating does not have good plating coverage. It is an object of the present invention to provide a laminate for high frequency circuits, which has good through-hole plating coverage.

[0005]

The present invention is characterized in that a sintered sheet obtained by mixing and sintering plastic powder and a plating catalyst is used as a dielectric layer.

The sintered sheet is manufactured by dispersing plastic powder in an organic dispersion medium, applying the dispersion on a carrier film, and drying and sintering. By dispersing the plating catalyst in the same manner as the powder of plastic, a sintered sheet to be the dielectric layer of the present invention can be obtained.

As the plastic powder, a polyolefin resin, for example, a homopolymer or copolymer of an olefin compound such as ethylene, propylene, 1-butene or 4-methyl-1-pentene is used. Polyethylene is preferable from the standpoints of processability, price, and the like.

The plating catalyst is a metal ion of Group 8 chemically adsorbed on an inert fine powder. Palladium ions, which are particularly excellent in heat resistance, are suitable as the metal ions of Group VIII. As the inert fine powder, aluminum silicate (for example, kaolin) is suitable, and those having a size of 0.5 μm to 50 μm are preferable because they are easily dispersed in the plastic powder. The compounding amount of the plating catalyst is 3 or more in the dielectric layer. If the amount is less than this amount, the desired effect of the present invention cannot be obtained. For the purpose of the present invention, there is no upper limit, but if a large amount of a plating catalyst is blended, the electrical insulation and heat resistance of a laminated plate will be affected.

In addition to plastic powder, organic halogen compound particles may be added as a filler if necessary. Examples of the organic halogen compound particles include decabromophenyl ether, hexabromobenzene, and the like. In particular, 1,2,3,4,7,8,9,10,13,
13,14,14-dodecachloro-1,4,4a, 5
Particles of 6,6a, 7,10,10a, 11,12,12a-dodecahydro-1,4,7,10-dimethanodibenzono (a, e) cyclooctene are preferred. The particles are commercially available from Occidental Chemical Company, USA under the trade name of Dechlorane Plus.

The reinforcing layer 2 is a glass cloth, a glass non-woven cloth, a synthetic fiber woven cloth, which is generally used for printed circuit boards.
It is composed of a base material such as non-woven fabric and a heat resistant resin. As the heat resistant resin, unsaturated polyester resin, epoxy resin, phenol resin, melamine resin, diallyl phthalate resin, polyimide resin, bismaleide triazine resin, polyphenylene ether resin, polyphenylene ether resin is crosslinked with a crosslinkable polymer or a crosslinkable monomer. Examples of the resin include

As the material of the metal conductor layer 3, foil such as copper, aluminum, nickel, iron, stainless steel is used.

The molding of the high-frequency circuit laminate according to the present invention is the same as that of a general printed circuit board. That is, a sintered sheet, a prepreg in which a base material is impregnated with a resin, and a metal foil are stacked, sandwiched between end plates, and thermocompression-molded by a multistage press. Molding pressure is 1 to 7.8 MPa, temperature is 120 to 2
It is carried out at 50 ° C. It is preferable to pressurize under reduced pressure.

[0013]

[Example] Ultra-high molecular weight polyethylene having an average particle diameter of 0.03 mm, a melting point of 136 ° C., a bulk density of 0.4 g / cm ^{3 and a} true density of 0.94 g / cm ³ (Mipelon XM220, using a trade name of Mitsui Petrochemical Industry Co., Ltd. 100 parts by weight, chlorine content 65%, average particle diameter 0.003 mm, bulk density 0.
67 g / cm ³ , true density of 1.9 g / cm ³ , 1, 2,
3, 4, 7, 8, 9, 10, 13, 13, 14, 14-
Dodecachloro-1,4,4a, 5,6,6a, 7,1
0,10a, 11,12,12a-dodecahydro-1,
80 parts by weight of 4,7,10-dimethanodibenzono (a, e) cyclooctene (using Dechlorane Plus # 25, trade name of Oxydental Chemical Co., USA), plating catalytic filler (average particle size of 0. 5 parts by weight of 003 mm aluminum silicate adsorbed paradiion ions) was mixed with toluene, coated on a polyethylene terephthalate film having a thickness of 50 μm, and dried at 175 ° C. for 10 minutes to obtain a sintered sheet.

A prepreg (resin content 60% by weight) in which a glass cloth having a thickness of 50 μm is impregnated with a brominated bisphenol A type epoxy resin on both sides of the sheet is used to form a thickness of 35 μm
Electrolytic copper foil is stacked and stainless steel plate is used at 175 ℃,
The laminate was heated and pressed at 2 MPa for 90 minutes to obtain a high-frequency circuit laminate having a thickness of 0.6 mm.

Comparative Example A laminate for a high frequency circuit having a thickness of 0.6 mm was obtained in the same manner as in the Example except that the plating catalytic filler was not added to the material for producing the sintered sheet.

A diameter of 0.9 is added to the above laminated plate for high frequency circuits.
A hole was drilled with a mm drill and electroless plating was performed.
As a result, no copper was deposited by electroless copper plating in the holes of the laminate of Comparative Example, but copper was deposited by electroless copper plating in the holes of the laminate of Example.

[0017]

EFFECTS OF THE INVENTION According to the present invention, a sintered sheet obtained by mixing and sintering a plastic powder and a plating catalyst is used as a dielectric layer. A laminated board can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a high-frequency circuit laminate according to the present invention.

[Explanation of symbols]

 1 Dielectric layer 2 Reinforcing layer 3 Metal conductor layer

Claims (1)

[Claims] 1. A laminate for a high-frequency circuit, comprising a sintered sheet obtained by mixing plastic powder and a plating catalyst and sintering the mixture as a dielectric layer.