JPS58206399A - Method of punching laminated 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 The present invention provides a punching die for a negative surface, and a punching section consisting of a group of punches for punching, and a method for thinning and smoothing the wall surface of the hole formed by the punching section. The present invention relates to a method for punching a laminate using a mold having a finishing section consisting of a group of punches.

With the recent high-density packaging of electronic devices, the use of through-hole boards has become active in order to increase the wiring density of printed wiring boards.Information processing technology that has traditionally been different from industrial use In the semi-industrial field that arose from the transition to related consumer products, glass cloth was used as a substrate for printed circuit boards due to reliability reasons.
Evox resin laminates, glass non-woven IJ-Epoquine resin laminates, etc. are used, and the price is expected to be as low as that of consumer equipment. In response to the lower prices of printed wiring boards in the industrial field, there is a desire to develop through-hole processing instead of the conventional drilling method.

In general, the characteristics of punched holes are that the blank is inserted between the punch and the die hole, and the hole is formed by cracks that occur within the blank. As a result, the hole wall roughness increases.

Therefore, the shape of the through-hole plating applied to the punched hole is more uneven than the through-hole plating applied to the drilled EL hole, and is considered to be unreliable.

In recent years, in order to improve the above-mentioned problems, a punching method (hereinafter referred to as the shaving method) has been proposed in which the wall surface of the hole obtained by punching is further smoothed by using a second punch. More specifically, there is a punching section consisting of a group of punches for making a hole in the mold on the side, and a finishing section consisting of a group of punches for scraping and smoothing the wall surface of the hole formed by the punching section. This is a processing method in which the blank is sent sequentially from the punching section to the finishing section and punched.

However, the above shaving method has serious problems. That is, the punching powder generated when cutting the wall surface of the punched hole in the finishing section is removed from the brush/grip. For shaving molds, the punches in the punching part and the finishing part are designed to have the same length, and the depth of penetration of the punch in the punching part and finishing part into the die hole when punching the blank is set to the same length as that of a general laminate. As with punching and punching, adjust it to about % of the thickness of the blank punk. When Sony Ping processing is performed at the above penetration depth, the blank is sandwiched between the punch and die hole at the punching part, and is destroyed by a crack that occurs at the line l- connecting the punch edge and the die hole edge, causing the blank to be punched out. Since the action involves punching and scraping blood, it is insufficient to remove the punching powder from the crack. In addition, the shape of the +] punched powder in the finishing section is cylindrical or 11
Since it is finer than the punching powder generated at the punching part, it is easy to cause an accident in which the punching powder is drawn into the inside of the hole when blank punching (when blank punching is performed). The following two problems occur regarding punching powder in the ridged area. First, removing the cylindrical punching powder or fine powder that has adhered around the hole in the finished part requires brushing, etc. This results in a huge 1+ drop in efficiency.

Secondly, when the punch is pulled out from the blank, the punching powder drawn into the hole becomes stuck to the wall of the hole due to the frictional heat generated between the punch and the blank. When the blank is a glass cloth-epoxy resin laminate, this phenomenon resembles a smear, and the punching powder cannot be removed sufficiently even if the inside of the hole is thoroughly cleaned. The shape of the through-hole plating applied to such a punched hole has larger irregularities than the through-hole plating applied to the drill θ Loe hole, and is evaluated as having no axis stability.

The purpose of the present invention is to prevent punching powder from remaining in the hole during shaving processing.In other words, the present invention aims to prevent punching powder from remaining in the hole during the shaving process. This is a method of punching by increasing the depth of penetration of the punch in the die hole by 03 to 3 times longer than the penetration depth of the punch in the blank when punching the blank.

Even if the penetration depth of the punch in the finishing section into the die hole when punching the blank is greater than the penetration depth into the die hole when punching the blank with the punch in the punching section, if the difference is less than 0.31111. , RL punching powder tends to adhere around the holes that have been finished. Also,
If the difference in penetration depth exceeds 3 am, a disadvantage arises in that the metal foil on the punch penetration side of the blank metal foil punch 1-plate swells up when the punch is pulled out after punching.

Next, the depth of penetration into the die hole during blank punching of the IJ punching part and finishing part of the mold for detailed explanation of the present invention is 1. Adjusted to lag, Kl dragon, 1611411 thickness J
Medium resin double-sided copper-clad laminate (Both surfaces of M-layer board base material glass 7)
, 41'', intermediate layer base glass nonwoven fabric) was punched out. (r
The test results for the punched Δ hole are shown in Table 1. The penetration depth of the punch into the die hole during blank punching in the punching part and finishing part of the comparative example mold is l, respectively.
lam, and punched out a double-sided copper-clad laminate similar to the example. The test results for the punched holes are shown in Table 1.

Table 1 Book-1 Punching powder adhesion rate Fist-2 Through-hole plating processing: After high-pressure cleaning, 25μ thick through-hole plating was applied.

As is clear from Table 1, according to the present invention, there is no adhesion of punching powder to the punching hole, so brushing around the punching hole and cleaning inside the punching hole are reduced, and through-hole plating is possible. The industrial value of this method is extremely significant, as there is no discernible difference between applying it to a drilled hole.

Claims (1)

[Claims] When punching a laminate board with a mold that has a punching section made up of a group of punches for punching and a finishing section made up of a group of punches for thinning and smoothing the wall surface of the hole formed by the punching section, It is characterized by making the penetration depth of the punch in the finishing section into the die hole of the mold when punching the blank 03 to 3 longer than the depth of penetration into the die hole of the die when blanking the punch in the punching section. A method for punching laminates.