JPS61197221A - Manufacture of electromagnetic wave shielding molded article - Google Patents

Abstract

PURPOSE:To manufacture easily a molded article to an inner wall of which electric wave shielding paints have been applied doubly under high working atmosphere, by applying said paints to the inside of a molded article which has been made into a double wall structure by filling the inside of the molded article with the electric wave shielding paint. CONSTITUTION:Parison plasticized and molten is arranged within molds 5, 7 and a blow molded article formed of an outer wall 2a and inner wall 2b is molded by applying blow molding to the parison. The inside of the molded blow molded article is filled with electric wave shielding paints 9, through which the paints are applied to the whole surface of the inner wall and dried after the remaining paints have been discharged. The outer wall and inner wall may also be brought into contact with each other. It does not happen that working atmosphere is made to deteriorate through spattering of the paints or a contained material is affected through stripping of the paints like a conventional case of application to a veneer and as painting is of dual paints electromagnetic wave shielding properties are favorable. The titled material is suitable for manufacturing of a casing such as a personal computer.

Description

【発明の詳細な説明】 産業上の利用分野 本発明は、電磁波を遮蔽可能なプラスチック成形品の製
造方法に関する。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a plastic molded article capable of shielding electromagnetic waves.

従来の技術 プラスチック成形品にて構成される電子機器等のケース
、例えばパーソナルコンビニータ、のハウジングケース
は、外部からの電磁波がケース内部の電子機器に影響し
たり、逆にケース内部の電子機器から発生した電磁波が
外部へ放出するのを防ぐために、電磁波遮蔽性が要求さ
れている。Conventional technology Cases for electronic devices, etc., made of plastic molded products, such as housing cases for personal convenience computers, can be affected by electromagnetic waves from the outside that affect the electronic devices inside the case, or vice versa. Electromagnetic wave shielding properties are required to prevent generated electromagnetic waves from being emitted to the outside.

従来のこの種のケースにおける電磁波の遮蔽手段として
社、ケースの内面あるいは外面に電磁波遮蔽性を有する
塗料で塗装するか、あるいは、ケースを成形するプラス
チック内に細かい電磁波遮蔽性フィラーを混入し【成形
材自体に電磁波遮蔽性を付与したもの（例えば特開昭５
９−２０４３００号公報、特開昭６０−１３５１６号公
報）がある。Conventional methods for shielding electromagnetic waves in this type of case include painting the inner or outer surface of the case with electromagnetic wave-shielding paint, or mixing fine electromagnetic wave-shielding filler into the plastic used to mold the case. Materials that have electromagnetic shielding properties (for example, Japanese Patent Application Laid-open No. 5
No. 9-204300 and Japanese Patent Application Laid-open No. 13516/1983).

発明が解決しようとする問題点 上記従来の技術における前者の塗装によるものでは、吹
き付けＫよる塗粒の飛散で作業環境が悪く、これをきら
って行なわれる刷子塗りでは仕上りが悪い上に能率が悪
く、さらにケースの使用中に塗料が剥離して収納物に悪
影響を及ぼす等の問題があった。Problems to be Solved by the Invention The former method of painting in the above-mentioned conventional technique creates a poor working environment due to the scattering of paint particles due to spray K, and brush painting, which is done in consideration of this, produces a poor finish and is inefficient. Furthermore, there were other problems such as the paint peeling off during use of the case, which adversely affected the stored items.

一方後者の混合材料を用いるものは、混入しようとする
電磁波遮蔽性フィラーがプラスチック内に均一に分散混
合しないで成形体内で電磁波遮蔽性フィラーの疎密がで
きてしまい、この疎の部分から電磁波が漏れてしまうこ
とがある。On the other hand, when using the latter mixed material, the electromagnetic shielding filler to be mixed is not uniformly dispersed and mixed within the plastic, resulting in the electromagnetic shielding filler being densely packed in the molded body, and electromagnetic waves leak from these sparse areas. Sometimes it happens.

また遮蔽性を高めるために電磁波遮蔽性フィラーの混合
量を多くすると成形品の機械的性質、特に耐衝撃性が低
下してしまう等の問題がある。Furthermore, if the amount of the electromagnetic wave shielding filler mixed is increased in order to improve the shielding properties, there is a problem that the mechanical properties of the molded article, especially the impact resistance, deteriorate.

問題点を解決するための手段及び作用 本発明は上記のことにかんがみなされたもので、ブロー
成形して外壁と内壁とからなる２重壁構造の中空成形品
を、外壁と内壁の内側対向全面が互いに接触しない形状
に成形し、その後この中空成形品の内部に電波遮蔽性を
有する塗料を充填してこの塗料を中空円全面に塗布し、
余った塗料をその後排出してから転溶するようにしてい
る。Means and Effects for Solving the Problems The present invention was conceived in view of the above-mentioned problems, and is made by blow molding a hollow molded product having a double wall structure consisting of an outer wall and an inner wall. molded into a shape that does not touch each other, then fill the inside of this hollow molded product with a paint that has radio wave shielding properties and apply this paint to the entire surface of the hollow circle,
The remaining paint is then discharged and then remelted.

実施例 本発明の実施態様を図面に基づいて説明する。Example Embodiments of the present invention will be described based on the drawings.

図中１は本発明方法を適用しようとするノく一ソナルコ
ンピュータのケースであり、このケース１は本体２と蓋
体３とを合せ面ＰＬにて接合した構成となっていて、こ
の両部材とも電磁波遮蔽性が付与されている。1 in the figure is a case of a Nokuichi sonal computer to which the method of the present invention is applied, and this case 1 has a structure in which a main body 2 and a lid body 3 are joined at a mating surface PL, and these two members Both have electromagnetic wave shielding properties.

以下上記両部材の一方、例えば本体２の製造方法を第２
図以下を参照して説明する。Hereinafter, one of the above two members, for example, the main body 2, will be manufactured using a second method.
This will be explained with reference to the figures below.

本体２の外側形状を有する凹形キャビティ４を成形した
第１の金型５と、本体２の内側形状を有する凸形キャビ
ティ６を成形した第２の金型７の対向間に１可塑化溶融
したパリスン８を配置しく第２図）、ついで、両全型５
，７を閉鎖してから、ブロー装置８ａより空気を吹き込
んでパリスン８をブロー成形し、外壁２ａと内壁２ｂと
からなる２重壁構造の中空成形体を成形する（第３図）
。このとき、外壁２ａと内壁２ｂの内側対向面は全面に
わたって離間されている。1. Plasticizing and melting is carried out between a first mold 5 that molds a concave cavity 4 having the outer shape of the main body 2 and a second mold 7 that molds a convex cavity 6 that has the inner shape of the main body 2. Place the parison 8 (Fig. 2), and then place the parison 8 on both sides (Fig. 2).
, 7 are closed, air is blown from a blowing device 8a to blow mold the parison 8 to form a hollow molded body with a double wall structure consisting of an outer wall 2a and an inner wall 2b (Fig. 3).
. At this time, the inner facing surfaces of the outer wall 2a and the inner wall 2b are spaced apart over the entire surface.

ついで上記中空の成形体内に電磁波遮蔽性を有する塗料
９を塗料充填装置１０にて充填しく第４図）、成形体内
周面に上記塗料を塗布する。Next, the hollow molded body is filled with a paint 9 having electromagnetic wave shielding properties using a paint filling device 10 (FIG. 4), and the paint is applied to the inner peripheral surface of the molded body.

その後排出装ａｉｌ　ＩＫて中空体内の余分の塗料を排
出すると共に乾燥する。After that, the excess paint inside the hollow body is discharged using the discharge device ail IK, and the hollow body is dried.

上記工程で中空成形品である本体２の中空内面全体に電
磁遮蔽性を有する塗料９が塗布され、本体２の外壁２ａ
及び内壁２ｂには電波遮蔽性が付与される。In the above process, a paint 9 having electromagnetic shielding properties is applied to the entire hollow inner surface of the main body 2, which is a hollow molded product, and the outer wall 2a of the main body 2 is
And the inner wall 2b is provided with radio wave shielding properties.

また上記本体２は中空となっており、このままでは内、
外壁２ａ、２ｂが不安定で撓み、振動等が生じることが
あるので、強度の向上、収納容積の増大で図る等の必要
性から第５図に示すように、両金型５，７をさらに締め
て外壁２ａと内壁２ｂを部分的に接触させてもよい。In addition, the main body 2 is hollow, and if left as is, the inside
Since the outer walls 2a and 2b are unstable and may cause bending, vibration, etc., it is necessary to improve the strength and increase the storage capacity, so as shown in FIG. The outer wall 2a and the inner wall 2b may be brought into partial contact by tightening.

なお上記実施態様において、中空成形体内に塗料９を充
填する作業を、成形品を金型５，７からはずしてから行
なってもよい。In the embodiment described above, the work of filling the paint 9 into the hollow molded body may be performed after the molded product is removed from the molds 5 and 7.

上記実施態様におけるパリスン８はポリエチレン、ポリ
プロピレン、ポリアミド、ＡＢＳ等プロー成形可能なプ
ラスチックが用いられる。The parison 8 in the above embodiment is made of a blow moldable plastic such as polyethylene, polypropylene, polyamide, or ABS.

また電磁波遮蔽性を有する塗料は、アクリル系、ポリウ
レタン系レジン等のバインダに、粉末材の銀、ニッケル
、銅、グラファイト等の電磁波遮蔽性フィラーを混入し
たものが用いられる。Further, the paint having electromagnetic shielding properties is made by mixing a binder such as acrylic or polyurethane resin with an electromagnetic shielding filler such as powdered silver, nickel, copper, or graphite.

なお成形材料及び塗料は上記のものに限られるものでは
なく、従来から用いられるものであればよい。The molding material and paint are not limited to those mentioned above, and any conventionally used materials may be used.

発明の効果 本発明によれば、電波遮蔽性塗料による外面塗装及び電
磁波遮蔽性フィラーを混合した混合成形材料を用いて電
波遮蔽性を得るようにした従来の手段による問題点を全
て解決することができる。Effects of the Invention According to the present invention, it is possible to solve all the problems caused by conventional means of obtaining radio wave shielding properties by using a mixed molding material mixed with an electromagnetic wave shielding filler and exterior coating with a radio wave shielding paint. can.

すなわち、衛生的な作業環境を保つことができると共に
、仮に塗料が剥離したとしてもケース内の収納物に悪影
響を及ぼすことがない。また塗料は中空体の内面の全体
に塗布されることＫより容器の厚み方向に見て塗布層が
２重になり、電波遮蔽性塗料を十分果たすことができる
。That is, it is possible to maintain a sanitary working environment, and even if the paint peels off, it will not adversely affect the items stored in the case. Furthermore, since the paint is applied to the entire inner surface of the hollow body, the coating layer becomes double when viewed in the thickness direction of the container, and the paint can sufficiently function as a radio wave shielding paint.

さらに成形品の強夏は電波遮閉材によって影響を受ける
ことがなく、通常の中空成形品と同等に製造及び取扱う
ことができる。Furthermore, the strength of the molded product is not affected by the radio wave shielding material, and it can be manufactured and handled in the same manner as ordinary hollow molded products.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明を適用しようとするケースの斜視図、第
２図から第５図は本発明の笑施態様を示す工程説明図で
ある。 ２ａは外壁、２ｂは内壁、５，７は金型、８はパリスン
、９は塗料。FIG. 1 is a perspective view of a case to which the present invention is applied, and FIGS. 2 to 5 are process explanatory diagrams showing embodiments of the present invention. 2a is the outer wall, 2b is the inner wall, 5 and 7 are the molds, 8 is the parison, and 9 is the paint.

Claims (1)

【特許請求の範囲】[Claims] 対向した分割金型５、７間に可塑化溶融したパリスン８
を配置し、ついで上記分割金型５、７を閉鎖すると共に
、ブロー成形して、外壁２ａと内壁２ｂとからなる２重
壁構造の中空成形品を、上記外壁２ａと内壁２ｂの内側
対向全面が互いに接触しない形状に成形し、その後この
中空成形品の内部に電波遮蔽性を有する塗料９を充填し
てその塗料９を中空全面に塗布し、余った塗料をその後
排出してから乾燥するようにしたことを特徴とする電磁
波遮蔽性成形品の製造方法。The parison 8 is plasticized and melted between the opposing split molds 5 and 7.
Then, the split molds 5 and 7 are closed and blow molding is performed to obtain a hollow molded product with a double wall structure consisting of an outer wall 2a and an inner wall 2b. are molded into a shape that does not touch each other, and then the inside of this hollow molded product is filled with a paint 9 having radio wave shielding properties, and the paint 9 is applied to the entire hollow surface, and the excess paint is then drained and dried. A method for manufacturing an electromagnetic wave shielding molded product, characterized in that: