JPH04196291A - Inner layer material - Google Patents

Abstract

PURPOSE:To obtain an inner layer material in which no foreign matter is generated, by covering the end face of the periphery of the material with a resin layer. CONSTITUTION:This inner layer material is adhered with a copper foil 2 on the surface of an insulting layer 1, and its cut end face is covered with a resin layer 3. The material is cut in a predetermined size from a large plate of a copper-plated laminated board of a specified length, and then finished to an inner layer material through various machining steps. The cut sectional surface is covered with the layer 3 to prevent foreign matters such as resin powder, glass cloth fluff, cut chips, etc., from being generated from the sectional surface, and hence, when an uneven part is generated or a circuit is formed, a malfunctioned circuit such as disconnection lack of a circuit pattern does not occur. Thus, the material in which no foreign matter is generated, is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an inner layer material of a multilayer laminate used for printed wiring boards and the like.

[Conventional technology]

Multilayer copper-clad laminates made of epoxy resin have been widely used as printed wiring boards. The inner layer material of the glass cloth base epoxy resin constituting such a multilayer laminate is cut into a predetermined size from a large plate of a standard size. Examples of cutting methods include shearing and sawing. The cut surface of a predetermined size is caused by foreign matter such as resin powder, glass cloth fluff, and chips generated during cutting adhering to the surface of the metal foil or the plate of the laminated molding during lamination processing.
It has been viewed as a problem because it causes irregularities in the laminated board and causes defective circuits such as disconnections and missing circuit patterns when circuits are formed. This problem is especially serious when forming fine circuits, as it increases the defective rate. For this purpose, the end face of the inner layer material after cutting is polished and chamfered using a router or belt sander, etc., and the end face of the inner layer material is heated with an infrared heater to weld the resin and prevent the above-mentioned powder falling off. However, foreign matter generated from the end surface has not yet been sufficiently resolved in post-processes such as laminating, exposing, and etching the inner layer material.

[Problem to be solved by the invention]

An object of the present invention is to provide an inner layer material that does not generate foreign matter.

[Means to solve the problem]

The present invention has been made in view of the above points, and the inventors have proposed an inner layer material constituting a multilayer laminate, characterized in that the peripheral end surface of the inner layer material is covered with a resin layer. The problem was solved by using an inner layer material.

The present invention will be explained below based on the drawings.

FIG. 1 is a sectional view of an inner layer material for a multilayer laminate according to the present invention, and FIG. 2 is a perspective view thereof.

In the inner layer material shown in FIG. 1, copper 12 is bonded to the surface of the insulating layer 1.
Usually, the cut end surface is coated with a resin layer 3.
30C11X30CI, 4 from a large board of double-sided copper-clad laminate of standard size such as 1m square, 1mx2m rectangle, etc. using a laminate board.
Cut into any predetermined size such as 5C11X25CI,
After coating the cut end surface with a resin layer, the copper foil can be formed into a copper circuit, and then subjected to surface roughening treatment such as blackening treatment.

Instead of the double-sided copper-clad laminate described above, a single-sided copper-clad laminate can also be used.

These copper-clad laminates include copper-clad glass-based epoxy resin laminates, polyimide resin laminates, polyphenylene oxide resin laminates, fluororesin laminates, modified resin laminates of these resins, and inorganic fillers. A laminate made from the above-mentioned resins and the like can be used.

The base material is not limited to glass, and inorganic fiber cloths and mats such as quartz fibers, highly heat-resistant organic fiber cloths and mats such as polyimide resin fibers, etc. can be used as the base material.

The resin layer covering the cut surface may be the same as or of the same type as the laminate resin used for the inner layer material. In particular, epoxy resins can be preferably used because they have excellent adhesive properties. Note that the epoxy resin can be used without being limited to one-component or two-component.

Preferably, the curing temperature is 160°C or less.

(Function) The inner layer material is cut into a predetermined size from a large copper-clad 7i board of standard size, and then subjected to various processing steps to be finished as the inner layer material.By covering the cut surface with a resin layer, This prevents foreign matter such as resin powder, glass cloth fuzz, and chips from forming on the cut surface, which prevents unevenness on the laminate, and prevents defective circuits such as disconnections and missing circuit patterns when forming circuits. No more outbreaks.

[Example] After cutting a 1 m square double-sided copper-clad glass cloth base epoxy resin laminate into a predetermined size of 25 Cffi x 50 cm square by shearing, primary cleaning was performed by high-pressure water washing and polishing, and then the cut laminate was Epoxy resin was applied to the end face and cured by heating.

A dry film is laminated onto the copper foil layers on both sides of this laminate, and a circuit pattern is formed through each process of exposure, development, and etching, and an inner layer material is obtained in which the surface of the copper layer of the circuit pattern is roughened by blackening treatment. Ta. In the dry film lamination and exposure steps described above, it was possible to prevent the contamination of foreign matter that would cause circuit breakage and defects, and in the development and etching steps, it was possible to prevent each liquid from being contaminated by foreign matter.

〔Effect of the invention〕

The inner layer material of the present invention does not generate foreign matter from the constituent materials of the inner layer material during post-processing steps. Therefore, in the multilayer copper-clad laminate obtained from this inner layer material, fine circuits can be formed with a reduced defect rate.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an embodiment of the present invention; FIG. 2 is a perspective view thereof. 1...Insulating layer 2...Copper foil 3...Resin layer Patent applicant Matsushita Electric Works Co., Ltd.

Claims (1)

[Claims] (1) An inner layer material constituting a multilayer laminate, characterized in that the peripheral end surface of the inner layer material is covered with a resin layer.