JP2001232596A - Drilling floor plate for printed board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floor plate applicable for recycling and improved in surface smoothness. SOLUTION: The drilling floor plate 1 for a printed board, which is formed of a resin composition with an acrylic rubber copolymerized with a polystyrene resin is used to achieve the above purpose. The floor pate 1 which does not contain a thermosetting resin preventive of recycling is applicable for 100% recycling. The improvment in the surface smoothness of the floor plate causes no burrs around holes in the surface of the printed board and requires no deburring process.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laying board used for drilling a printed circuit board, and more particularly to a laying board which can be recycled and has improved surface smoothness.

[0002]

2. Description of the Related Art A typical printed circuit board first has a hole of a predetermined size at a predetermined position of a copper-clad laminate (hereinafter referred to as a "printed substrate") in which copper foil is provided on both sides of a resin plate. Drilling, copper plating on the inner surface of the hole to form a through hole, printing a resist material in a predetermined pattern on the copper foil of the printed circuit board, and etching away the exposed copper foil portion After forming a predetermined wiring pattern and a manufacturing process having at least a step of dissolving and removing the resist material, electronic components such as integrated circuits are mainly mounted on one surface, and the other surface is mounted on the other surface. Are manufactured by mounting contact materials and auxiliary parts.

[0003] Among these steps, in the step of drilling a printed board, as shown in FIG. 1, a plurality of printed boards 3 are stacked on a laying board 1 and an entry board 2 is placed on the printed board 3 from above. Is made by sequentially drilling holes 5 having a predetermined diameter at predetermined positions on the superimposed ones. Bakelite (phenol-formaldehyde resin) having a thickness of about 1.5 mm is mainly used as the spreading board 1 used at this time, and the entry board 2 has a thickness of 0.15 to 0.5 mm.
Aluminum foil of about 2 mm is mainly used.

[0004]

By the way, in recent years, from the viewpoint of consideration for the environment, there is a demand for environmental management by recycling and reduction of industrial waste which is one of the causes of environmental pollution. For this reason, the review of various environmentally friendly products or the materials that make them up has been activated. Under such circumstances, most of the above-mentioned entry board 2 for drilling a printed circuit board is made of bakelite made of a thermosetting resin, whereas aluminum foil is mostly used and recycled. For this reason, there is a problem that it cannot be recycled and is treated as industrial waste.

[0005] Furthermore, in the case of the Bakelite laying plate 1, there is a problem that burrs are easily generated around holes on the surface of the printed circuit board in contact with the laying plate during drilling. The occurrence of burrs is considered to be due to the gap between the bakelite laying board and the printed board, and if the surface smoothness of the laid board can be further improved, the gap between the laid board and the printed board is It is considered that the size of the burrs is reduced, and the generation of burrs can be suppressed, and the deburring step can be omitted.

The present invention has been made to solve the above-mentioned problem while paying attention to such a viewpoint, and provides a laying board which can be recycled and has improved surface smoothness.

[0007]

The laying board for drilling a printed circuit board according to the present invention is characterized in that it is made of a resin composition obtained by copolymerizing acrylic rubber with polystyrene resin.

According to the present invention, since the resin composition is formed from a resin composition obtained by copolymerizing an acrylic rubber with a polystyrene resin which is a thermoplastic resin, it is 100% recyclable. Therefore, it meets the purpose of environmental conservation, and can be used as an economical and practical flooring by re-commercialization. Moreover, the obtained laying plate has improved surface smoothness. This is presumed to be due to the fine crystals of the laying plate. Therefore, in the laying board of the present invention, the gap between the laying board and the printed board is reduced due to the improved smoothness of the laying board surface, so that the periphery of the hole on the printed board surface in contact with the laying board is improved. Can be suppressed, and as a result, the deburring step can be omitted.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates to a laying board for drilling a printed circuit board. The object of enabling recycling and eliminating the need for a deburring step by improving surface smoothness is to use an acrylic polystyrene resin. This problem has been solved by a slab made of a resin composition obtained by copolymerizing rubber.

Hereinafter, each material constituting the present invention and the compounding amount thereof will be described.

As the polystyrene resin, a pure polystyrene resin (commonly referred to as GPPS) is used. This polystyrene resin is thermoplastic, but has the property of being vitreous and brittle.

Acrylic rubber is a synthetic rubber containing alkyl acrylate as a main component and having heat resistance, oil resistance, weather resistance and ozone resistance.

When a polystyrene resin and an acrylic rubber are copolymerized, the properties of the glassy and brittle polystyrene resin (GPPS) are modified, and a resin composition having fine crystals and flexibility is obtained. This resin composition contains acrylic rubber in an amount of 2.0% by mass or more and 50.0% by mass.
It is preferable to add and copolymerize at the following ratio. This range is a range in which a resin composition having fine crystals and having flexibility can be obtained, and is also economical.

When acrylic rubber is added at a ratio of less than 2.0% by mass and copolymerized, the resulting resin composition may not have sufficient flexibility, and cracks may occur when used as a laying board. And may be difficult to handle. On the other hand, when acrylic rubber is added at a ratio exceeding 50.0% by mass and copolymerized, a large amount of acrylic rubber having a relatively high market price is used, so that the material cost of the obtained resin composition increases. In some cases, the result is not economically favorable. In addition, acrylic rubber is 30.0 mass%.
If it is the following, at least the effect of the present invention can be exhibited, and it is more economically preferable.

A laying board is manufactured using the obtained resin composition. The method of manufacturing the laying board can be the same as the conventional method of manufacturing a board from a general resin composition, and is not particularly limited. For example, a predetermined amount of a polystyrene resin and an acrylic rubber are blended and kneaded, then, through a copolymerization step, a granulation step, etc., to produce a copolymer resin composition, and then, the copolymer resin composition is prepared. It can be used to produce a slab of predetermined thickness.

The spread sheet for drilling a printed circuit board of the present invention does not use a thermosetting resin.
Can be recycled. Furthermore, it is excellent in flexibility and easy to handle, and does not break when drilling.

The surface of the laying board has improved smoothness as compared with a conventional baked laying board. This is presumed to be due to the fact that the spreadsheet of the present invention uses a resin composition in which fine crystals have been formed by copolymerization, and therefore, the resulting spreadsheet also has fine crystals. Is done. Since the unevenness of the surface of the laying board is improved due to the improvement of the smoothness of the laying board surface, a gap between the laying board and the printed board is reduced or closely adhered. Therefore, as shown in FIG. 1, when the printed circuit board 3 is drilled by the drill 4, a remarkable effect that no burrs are generated around the holes 5 on the surface of the printed circuit board in contact with the laying plate 1 is exerted. As a result, when drilling a printed circuit board using the spreading board of the present invention, the deburring step after the drilling step of the printed board can be omitted.

Suppression of burrs improves the quality of the printed circuit board itself, and in the present situation where the distance between holes is more closely processed, the drill tip caused by burrs generated around the adjacent holes is reduced. Since escape can be prevented, the positional accuracy of the holes can be further improved.

Further, when the surface smoothness of the laying board is improved, the fine deflection of the printed circuit board due to the minute surface unevenness of the laying board when drilling is reduced, so that the drill tip escapes or the hole Are not formed obliquely, and the positional accuracy of drilling is also improved.

By using the laying plate of the present invention, even when a drill having a small diameter of 0.20 mm or less is used for drilling a printed circuit board, escape of the tip of the drill can be prevented, and A printed circuit board having excellent positional accuracy can be manufactured.

In the case where the slab after being used for drilling is to be recycled, the collected slab is crushed,
After being melted, it can be used as a recycled resin composition material. Then, the recycled resin composition material is used, and if necessary, a new resin composition material is added, so that a flooring board as a recycled product can be manufactured.

Also, an entry board 2 made of a resin composition obtained by copolymerizing an acrylic rubber with a polystyrene resin can be manufactured. The obtained entry board 2
Can be economically preferably used as a substitute for an entry board made of a conventional aluminum foil.

[0023]

The present invention will be described below in detail with reference to examples and comparative examples. Example 1 A printed board having a length of 505 mm, a width of 605 mm, and a thickness of 1.5 mm was obtained by using a copolymer resin composition obtained by adding an acrylic rubber to a polystyrene resin so as to have a concentration of 25% by mass and performing a copolymerization reaction. Laying board 1 was manufactured.

Four printed circuit boards 3 to be punched were placed on the spreading board 1, and an entry board 2 made of aluminum and having a thickness of 0.2 mm was further placed thereon. Drilling was performed there using a small diameter drill 4 having a diameter of 0.35 mm. The drilling conditions were such that the drill was rotated at a speed of 120,000 revolutions / minute, and 28,000 holes were drilled. (Comparative Example 1) As the laying plate 1, 505 mm in length and 605 in width
Drilling was performed under the same conditions as in Example 1 except that a Bakelite spreadsheet having a thickness of 1.5 mm and a thickness of 1.5 mm was used. (Evaluation results) The recyclability of the slab after drilling was examined. The slab of Example 1 was 100% recyclable. The slab of Comparative Example 1 was thermosetting and could not be recycled.

The state of occurrence of burrs after drilling was evaluated by finger touch. The finger touch evaluation is a method of evaluating the degree of burr generation by tracing the surface of each printed circuit board on the laying board side with a fingertip. The printed circuit board punched using the spreading board of Example 1 did not generate burrs, whereas the printed board punched using the spreading board of Comparative Example 1 did. A take-up process was required.

[0026]

As described above, according to the spread sheet for boring a printed circuit board of the present invention, it is 100% recyclable, in line with the purpose of environmental conservation, and is economical and practical by re-commercialization. It can be used as a laying board. In addition, the obtained laying board can ensure sufficient quality, such as crack prevention during work, and improve the smoothness of the laying board surface, thereby reducing the generation of burrs on the laying board side surface of the printed circuit board. Can be suppressed.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of a spread sheet for boring a printed circuit board according to the present invention.

[Explanation of Signs] 1 Laying Board 2 Entry Board 3 Printed Circuit Board 4 Drill 5 Hole

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Nobuyuki Goto 1640-187 Mizuguchichoyama, Koka-gun, Shiga F-term (reference) 3C036 AA01 3C060 AA11 BA05 BG06

Claims (1)

[Claims] 1. A sheet for drilling a printed circuit board, comprising a resin composition obtained by copolymerizing an acrylic rubber with a polystyrene resin.