JPS6266928A - Laminated board for thermoforming and molding method thereof - 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 [Field of Industrial Application] The present invention relates to a laminate plate suitable for manufacturing a case having electromagnetic wave shielding properties by blowing or vacuum forming (referred to as aged molding), and a method for forming the same. It is something.

[Conventional technology]

In order to manufacture a housing having electromagnetic shielding properties by blowing or thermoforming, metal f3 is used, and the metal foil in this case is required to have superplasticity. As a superplastic alloy, Z n
At alloys, At-Cu alloys, etc. are known, but when manufacturing casings using these superplastic alloys, the molding temperature (70 to 140°C) of the resin used for lamination and the Since the molding temperatures of 1 and 2 differ greatly, even if the 8L layer is made with resin, it is not practical as a thermoforming laminate.

As a lead alloy superplastic material, 62%Sn-58%P
The eutectic alloy of b (% indicates weight %; the same applies hereinafter) is superior!
It is known that it has different characteristics.

However, although this Pb-Sn eutectic alloy exhibits excellent superplasticity, it is difficult to use because Sn is expensive.

In addition, a superplastic phase of a Pb-19%Sn alloy in which Sn'r is reduced to the limit has been announced, but the fine crystal grains of this alloy are unstable, and as a superplastic material, it deteriorates severely over time, making it difficult to use. No.

The present inventors previously reported that Sn10-30%, cdo,
A Pb-Sn-Cd superplastic alloy characterized by having a composition of 5 to 30% balance Pb and unavoidable impurities has been filed.

This superplastic lead alloy contains Sn10-30, CdO, 5-3
Pb containing 0% and the remainder consisting of Pb and inevitable impurities
-Cd -Sn-based superplastic lead alloy (hereinafter Pb -Cd -
It is called 3n alloy. ).

[Problem that the invention seeks to solve]

In terms of alloys that exhibit superplasticity at resin molding temperatures, lead alloys that exhibit superplasticity at relatively low temperatures are advantageous.

The present invention aims to utilize superplastic lead alloys, particularly the above-mentioned Pb-Cd-8n alloys.

The present invention provides a thermoforming laminate having excellent electromagnetic shielding properties and excellent formability by laminating Pb-Cd-Sn alloy plates, strips, and foils and resin plates and strips, and a method for forming the same. The purpose is to provide

[Means for solving problems]

The present inventor used a large number of resins that can be thermoformed at temperatures around 100°C, where the Pb-Cd-8n alloy exhibits superplasticity, and laminated these resins with the Pb-Cd-Sn alloy. The test was repeated. As a result, Pb -Cd -Sn
It has been found that aromatic polyether resins, particularly polyphenylene oxide (commonly known as Noryl), are suitable resins for lamination and thermoforming with alloys.

In the case of lamination, the Pb-Cd-Sn alloy and the resin may be bonded together using a commonly used adhesive method such as a thermocompression bonding method using a hot-melt adhesive commonly used as an adhesive. Thermoforming of laminates is 110°
It has been confirmed that the reaction can be carried out at a temperature of 165°C to 165°C, preferably 120° to 130°C.

The present invention has been made based on the above findings, and the first aspect of the present invention is to provide a thermoforming laminate having a multi-layer structure formed by adhering a superplastic lead alloy layer and an aromatic polyether resin layer. In an embodiment of the plate, the superplastic lead alloy is Sn1
0-30% by weight, Cd005-30% by weight, balance Pb
and unavoidable impurities, and the aromatic polyether resin layer is made of polyphenylene oxide,
The thermoforming laminate has a three-layer structure with a hot-melt adhesive layer between the superplastic lead alloy and the aromatic polyether resin layer, or a superplastic lead alloy sandwiched between two layers of the aromatic polyether resin. The present invention is characterized in that it has a five-layer structure in which a hot-melt adhesive layer is disposed between the superplastic lead alloy and the adhesive layer, respectively.

Furthermore, a second invention is a method for molding a housing, characterized in that the thermoforming laminate having a plurality of structures according to the first invention is blow molded at a temperature of 110 to 135°C.

[Effect]

The effects of the Pb-Cd-Sn alloy and resin that constitute the present invention will be described.

As mentioned above, the Pb-Cd-8n alloy developed by the present inventors is an alloy that satisfies both superplasticity and economic efficiency.

Why was the composition range limited in the Pb-Cd-Sn system used in the present invention? I will explain next.

(Sn) This component has the effect of refining all grains, but if the amount added is less than 10%, the refining effect will be extremely poor and superplasticity will be lost. Further, in the range up to 62% Sn addition, the improvement in superplasticity tends to be saturated when Sn exceeds 30%, but as the Sn addition amount increases, superplasticity is improved.

From the above, an Snn content of 10 to 30'' is appropriate.

(Cd) By adding this component to the above-mentioned Pb-Sn alloy, it has the effect of further refining the crystal grains, and also has the effect of suppressing the coarsening of the crystal grains during rolling. It is possible to impart superior superplasticity. However, if the amount of Cd added is less than 0.5%, the effect of suppressing coarsening of crystal grains will be insufficient, so the amount of Cd added must be 0.5% or more.

Furthermore, in order to achieve a sufficient crystal refinement effect, C
The amount of d added is preferably 3% or more. Also, the amount of Cd added is 20%
If it exceeds 30%, the superplasticity improvement efficiency approaches saturation, and if it exceeds 30%, it actually worsens, so from an economic standpoint, it is meaningless to add more than 30%.

From the above, the amount of Cd added is suitably 0.5 to 50%, preferably 3 to 20%.

This Pb-Cd-Sn alloy has superplasticity even at temperatures below 110°C and can be formed.
The higher the molding temperature, the lower the molding pressure, which tends to make molding easier. However, all Pb-Cd-Sn metallurgy related to the present invention have a ternary eutectic phase with a ternary eutectic liquid phase point of about 140°C, so if the forming temperature exceeds 140°C, it will melt and form. Of course I can't.

Therefore, industrially, the temperature should be controlled so as not to exceed 135°C, which is the upper limit of the molding temperature.

When molding a layered plate of No. 8, it is necessary to mold it under narrower molding conditions than the molding conditions for a Pb-Cd-Sn alloy or resin alone. In other words, if the moldability of the Pb-Cd-Sn alloy and the resin is different (depending on the combination of processing stress and molding speed), this will cause the moldability to deteriorate, such as slowing the molding speed of the laminate or not being able to form it into a predetermined shape. becomes. Judging from the experience of conducting various molding tests using resins and Pb-Cd-Sn alloys in combination, Pb-Cd-Sn alloys have superplasticity even in the temperature range from 98°C to less than 110°C. The moldability of the resin plate is inferior to that of a resin plate kept at a suitable molding temperature, and as a result, the moldability of the laminated material is also insufficient.

In order to match the moldability of the resin and Pb gold alloy,
The Pb-Cd-Sn alloy needs to be molded at a temperature of 110° to 135°C, preferably 120° to 130°C.

and 110° to 165°C, preferably 120° to 130°C
Aromatic polyether resins, particularly polyphenylene oxide (commonly known as noryl resin) as resins exhibiting good moldability at temperatures of
It is most suitable as a partner resin material to form a sticky layer with Sn-based superplastic alloy. Note that the laminate of the present application is not only made of rad as shown in the 'iTI diagram, but also made of Pb-Cd-S as shown in Figure 2.
N-based alloy sandwiched with resin or this'
f! ! : Laminated ones are also possible. It is preferable to use a film-like hot-melt type resin with a melting point of 100° C. or less as the adhesive, but other adhesives may be used. As the adhesion method, a commonly used method such as thermocompression bonding may be used.

Next, an example will be described.

〔Example〕

2mm thick polyphenylene oxide resin (Tsutsunaka Plastic Industry Sakauri product name Sunroid Noryl pN8115L
By blow molding, the width is 90, the length is 120, and the depth is 2.
125°C for molding into a 5-pan housing (deployment magnification 2.2)
, it took 6 minutes under the condition of air pressure 3 kli + 1- (
For the last 30 seconds, the pressure was raised to within 7k to get the shape right. same as below). This resin plate was coated with 0.2 m thick Pb-Cd-Sn alloy plate having a composition of Pb-16wt%Sn-20wt%Cd.Atomer film Vg300-5 manufactured by Tokyo Celluloid Co., Ltd. was used as an adhesive for the entire Pb-Cd-Sn alloy plate.
Using a 0μ film, thermocompression bonding (contact N) was performed as shown in Figure 1.
) and molded as a three-layer laminate under the same conditions, the molding time was also 3 minutes.

A 2-layer thick PVC resin plate with a molding temperature of 90°C (
It also took 6 minutes to mold the above-mentioned casing at a temperature of 90° C. (trade name: Kaidak) and an air pressure of 60° C. However, a laminated plate made by layering a Pb-Cd-Sn alloy plate with a thickness of 0.2 mm on this resin plate was molded for 10 minutes at a temperature of 90°C and an air pressure of 61 cm, but the moldability was poor and the above-mentioned casing could not be obtained. There wasn't. Furthermore, the molding temperature was increased to 100℃, 110℃, 120℃, and 130℃.
I tried molding instead of , but the results were just as bad.

〔Effect of the invention〕

The thermoforming stock laminate of the present invention has excellent thermoformability as seen in Example V above, and furthermore, if molded under the molding temperature conditions of the molding method of the present invention, it can shield electromagnetic waves. It is possible to manufacture the housing by simple processing.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic cross-sectional views of the thermoforming laminate of the present invention, respectively. 1 is a Pb-Cd-Sn alloy, 2 is a polyphenylene oxide resin, and 6 is an adhesive. Agent Patent Attorney Masaru Sato Year II rI! i No. 22 Procedural Amendment (voluntary) October 22, 1955

Claims (6)

[Claims] (1) A laminate for thermoforming characterized by having a multilayer structure formed by adhering a superplastic lead alloy layer and an aromatic polyether resin layer. (2) The superplastic lead alloy contains 10 to 30% by weight of Sn and Cd.
The thermoforming laminate according to claim 1, characterized in that the Pb content is 0.5 to 30% by weight, and the balance is Pb and unavoidable impurities. (3) The thermoforming laminate according to claim 1, wherein the aromatic polyether resin layer is made of polyphenylene oxide. (4) A hot-melt adhesive layer is disposed between the superplastic lead alloy layer and the aromatic polyether resin layer to form a three-layer structure. Thermoforming laminate according to item 3. (5) A superplastic lead alloy is sandwiched between the two layers of the aromatic polyether resin, and a hot melt adhesive layer is arranged between the superplastic lead alloy and the resin layer to form a five-layer structure. A thermoforming laminate according to claims 1 to 3. (6) A thermoforming laminate with a multi-layer structure made by bonding a superplastic lead alloy layer and an aromatic polyether resin layer 110 to 13
A housing molding method characterized by blow molding at a temperature of 5°C.