JPH05121875A - Manufacture of multilayer printed wiring board - Google Patents

Abstract

PURPOSE:To realize good operativity during manufacture and reduction of a manufacturing cost without lowering positioning precision of a substrate material. CONSTITUTION:After a guide tube 2 is engaged with a positioning pin 1 which stands upwright at a corner part of a plate-like die 3, a mirror surface plate 4 is engaged with the guide tube 2, a substrate material A for a multilayer printed wiring board is engaged with the guide tube 2 in the order of a copper foil 5, a prepreg 6, a core material 7A, a prepreg 6, a core material 7B, a prepreg 6 and a copper foil 5 one by one, the mirror surface plate 4 is laminated thereon and a necessary number of them are laminated repeatedly thereon. After the die 3 is removed, it is introduced to a press device and laminated integrally.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a substrate for a multilayer printed wiring board.

[0002]

2. Description of the Related Art Generally, a multilayer printed wiring board used for increasing the density of wiring and improving the signal transmission speed between mounted components is composed of two or more printed circuit boards each having a circuit pattern formed therein. In the state where the core materials are aligned with each other, they are laminated and integrated with the outer layer material or the copper foil through the prepreg for adhesion and insulation.

The substrate of such a multilayer printed wiring board is
Since the conductors that form the circuit pattern have a fine wiring structure, a high degree of dimensional accuracy is required, and the conductor is usually manufactured by the following method.

That is, as shown in FIG. 3, the guide pin 10 is erected upright on a flat plate mold (for example, 500 mm square) having a thickness of 5 to 10 mm and having a through hole 11a at a predetermined position. Next, the guide pin 10 is arranged in the same arrangement as the through hole 11a.
A substrate material A consisting of a copper foil (or an outer layer material) 5 in which a guide hole a through which is inserted, a prepreg 6, a core material 7A, a prepreg 6, a core material 7B, a prepreg 6, and a copper foil (or an outer layer material) 5 are formed. Then, fit in the guide pin 10 in this order. Next, a stainless mirror plate 12 (having a thickness of 1 to 2 mm) having a guide hole 12a having a diameter of 0.2 to 2 mm larger than that of the through hole 11a is superposed and fitted at a position corresponding to the through hole 11a from above. Further, such a substrate material A and a mirror plate 12
The above-mentioned stacking is repeated by the required number, and the flat plate-shaped mold 11 similar to the above is fitted to the guide pin 10 at the uppermost position. When molding these, a plurality of sets of substrate materials A held between two upper and lower molds 11, 11 are introduced into a press machine and heated and pressed to be laminated and integrated.

[0005]

However, in the above-mentioned conventional method, the core material 7A on which a fine circuit pattern is formed,
When the 7B and the copper foils 5 are stacked, the guide pins 10 must be stably and vertically supported by the mold 11 in order to accurately position them.
Requires a thickness of about 5 to 10 mm.

For this reason, the weight of each die is very heavy, for example, about 20 kg when it is made of stainless steel having a thickness of 10 mm and a square of 500 mm. Therefore, there is a problem that when this is fitted into the guide pin and when it is introduced into the press machine, it is difficult to transfer it, which imposes a heavy burden on the worker, and also lacks safety in work.

Further, in order to accommodate the above-mentioned molds in a multi-stage press, it is necessary to prepare molds having 5 to 10 pairs, that is, 10 to 20 faces, and the manufacturing cost is remarkably high in terms of the required number of molds. There is also the problem of increase.

As a method for solving the above problems, it is considered that the material of the mold may be changed from stainless steel to aluminum which is inexpensive and has a small specific gravity. However, since aluminum is softer than stainless steel, the guide hole will deform when it is repeatedly used, and the positional accuracy of the substrate material due to the guide pin cannot be maintained, and when a foreign substance enters the mold surface, a recess is created. Since it is easy to cause defects on the surface of the wiring substrate, it cannot be a solution at this time.

The present invention solves the above-mentioned problems and allows the guide pins to be held vertically regardless of the thickness of the die used, without lowering the positioning accuracy of the substrate material. An object of the present invention is to efficiently provide a substrate for a multilayer printed wiring board, which is excellent in workability during manufacturing and does not increase the manufacturing cost.

[0010]

In order to solve the above-mentioned problems, in the present invention, a guide tube is fitted into a positioning pin that stands upright on the surface of a mold, and then a through hole that aligns with the outer peripheral surface of the guide tube. A plurality of substrate materials in which a mirror surface plate formed so as to correspond to the pins is fitted into the guide tube, and further, guide holes having the same size and the same arrangement as the through hole are formed, and a mirror similar to the above separately provided. The face plate is repeatedly fitted into the guide tube in a required number of times, and then the pins are removed together with the mold, and the space between the mirror face plates is heated and pressed to integrally laminate the substrate materials.

[0011]

In the method of manufacturing a substrate for a multilayer printed wiring board according to the present invention, since the guide tube is held in a vertical state by the positioning pin that stands upright on the surface of the mold, a thick mold for supporting the guide tube. Becomes unnecessary. In addition, since the multiple mirror plates align the outer peripheral surface of the guide tube with the through holes and support it, the positioning accuracy will not change even if the pin for positioning is removed from the guide tube and the mold is removed. There is no. Therefore, it is not necessary to introduce a heavy die into the press,
Since only one side of the mold needs to be used during assembly, manufacturing cost, workability and safety are improved.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, after a guide tube 2 is fitted on a positioning pin 1 which stands upright at a corner of a flat plate-shaped mold 3, the guide tube 2 corresponds to the pin position of the mold 3 and the guide tube 2 is inserted. A mirror plate 4 having a through hole 4a having a diameter that fits the outer diameter is fitted to the guide tube 2 and placed on the die 3, and then the pin 3 of the die 3 corresponds to the guide tube 2 The substrate material A for a multilayer printed wiring board having a guide hole with a diameter matching the outer diameter of the copper foil 5, the prepreg 6, the core material 7A, the prepreg 6, the core material 7B, the prepreg 6, and the copper foil 5 in this order. The tube 2 is fitted and overlapped, and the mirror surface plate 4 is fitted and overlapped on the guide tube 2 further thereon. Next, the required number of the multilayer printed wiring board material A and the mirror surface plate 4 are alternately and repeatedly stacked. Finally, as shown in FIG. 2, with the mold 3 removed together with the fixing pin 1, the mold 3 was introduced between the hot plates 8 and 9 of the press machine to be integrated under heat and pressure.

The material of the mold 3 is preferably stainless steel or super hard stainless steel in consideration of durability. Since the pin 1 is fixed to the mold 3, it is not necessary to increase the thickness to 5 to 10 mm, but if it is too thin, warpage may occur, so 3 to 8 mm is appropriate. Can be said.

The material of the pin 1 is preferably made of super hard stainless steel or the like in consideration of durability, and it is desirable that the diameter thereof is also high. Therefore, it is suitable that the material is about 2.0 to 4.0 mm. ..

Regarding the shape of the guide tube 2 fitted to the pin 1, first, it is appropriate that the inner diameter of the guide tube 2 has a clearance of 0.05 to 0.20 mm on one side with respect to the outer diameter of the fixed pin 1. From the viewpoint of maintaining strength, the wall thickness must be 0.5 mm or more. In the embodiment, the guide hole diameter of the mirror plate 4 and the substrate material for the multilayer printed wiring board is 5.00 mm, the outer diameter of the guide tube 2 is 4.98 mm, the inner diameter is 3.2 mm, and the diameter of the fixing pin is 3.0 mm. And

The material of the mirror plate 4 is preferably cemented stainless steel from the viewpoint of durability and hardness, and the diameter of the through hole 4a into which the guide tube 2 is inserted is 5 to 20 μm on one side of the guide tube diameter.
A clearance of m is appropriate. If the clearance is smaller than 5 μm, the workability is poor because the resistance to the fitting into the guide tube 2 is great. Further, with a clearance larger than 20 μm, a problem arises in that the guide tube 2 is securely fixed, and the core material mutual alignment accuracy of the multilayer printed wiring board substrate is deteriorated. The thickness is not particularly limited, and it can be used within a commonly used thickness range of 1 to 2 mm.

In order to separate the pin 1 together with the mold 3 from the assembled state as shown in FIG. 1, for example, a roller stand (not shown) or the like is interposed between the mold 3 and the mirror surface plate 4. Then, only the table supporting the mold 3 needs to be pushed down, and further transfer can be performed.

In the method according to the present invention, the pin 1 and the guide tube 2 fixed to the mold are positioned and fixed at the initial stage of assembly, and all the mirror-finished plates 4 and guide tubes 2 used for the assembly are introduced at the time of introduction of the press machine. The positioning is fixed. That is, if the number of substrate materials for the multilayer printed wiring board to be introduced into the upper and lower heating plates of the pressing machine is five, the guide tube 2 is fixed by the six-sided mirror-finished plate 4, so that the positioning accuracy is extremely high. Will be good. The positioning accuracy is not inferior even in the case of forming one sheet, but in general, a large number of sheets of 5 to 10 sheets are used. Therefore, a thin mirror surface plate 4 is used to fix the guide tube 2. However, since the fixation becomes multi-point support, the positional accuracy can be obtained in the same way as the conventional method.

The positional deviation amount of the substrate for a multilayer printed wiring board molded according to the present invention is 80 μm at maximum, and the positioning is exactly equal to 80 μm by the conventional method which is carried out at the same time, that is, the molding method using a pair of upper and lower molds. It was precision.

[0021]

As described above, according to the present invention, since only one surface of the expensive mold is used and multi-stage molding can be performed, the manufacturing cost required for the mold can be reduced and the heavy mold can be transferred. Since the transshipment work can be omitted, the manufacturing work is facilitated and the safety thereof is improved. Therefore, it can be said that the present invention has a very high industrial utility value.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a mold showing a state in which a multilayer printed wiring board substrate is assembled by a manufacturing method according to an embodiment.

FIG. 2 is a vertical cross-sectional view of a mold when the press machine is introduced.

FIG. 3 is a vertical cross-sectional view of a mold showing a manufacturing method of a conventional example.

[Explanation of symbols]

 1 pin 2 guide tube 3 mold 4 mirror plate 4a through hole A substrate material

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Claims (1)

[Claims] 1. A guide tube is fitted into a positioning pin that stands upright on the surface of a mold, and then a mirror plate having a through hole aligned with the outer peripheral surface of the guide tube is formed corresponding to the pin. And a plurality of substrate materials each having guide holes of the same size and the same arrangement as the through holes and the same mirror plate separately provided are repeatedly fitted to the guide tube in the required number of times, and then the pins A method for manufacturing a substrate for a multilayer printed wiring board in which the substrate is removed together with a mold, and the substrate materials are laminated and integrated by heating and pressing between the mirror-finished plates.