JPS6078746A - Manufacture of conductive synthetic resin molded shape - 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 relates to a method for manufacturing a synthetic resin molded article having electrical conductivity.

Conductive synthetic resin molded products are often used as storage containers or bags for storing semiconductor elements such as ICs and LSIs, electronic equipment parts, and precision equipment parts, or as packaging sheets 1 or films for wrapping these. It plays a role in preventing dust from adhering to the above elements and parts and preventing static electricity.

Conventionally, the conductive sheet 1~ which is the material 1 of this molded product is a base '4Δ made of a thermoplastic synthetic resin sheet or film.
However, in the case of this manufacturing method, the Il/J of the nonwoven fabric to the base material is When bonding is carried out using the roll press method, the temperature and pressure are lower than with the hot press method, so the nonwoven fabric does not adhere completely to the base material, and some of the conductive fibers that make up the nonwoven fabric are exposed to the surface of the nonwoven fabric. Therefore, when such a conductive sheet is used as a molding material, the fluffy portion of the conductive fibers breaks during use, and the MI from the surface of the sheet 1.
IIIt, which not only results in a decrease in conductivity;
The released II Vikiri caused dust and caused environmental deterioration. Furthermore, when a molded product such as a container is manufactured using a conductive sheet with fluff as described above, fiber bridges occur on the inside corners of the molded product, and the fluff of the fibers becomes even more noticeable on the flat parts. Therefore, the molded product could not be used for the above-mentioned purposes.

An object of the present invention is to provide an IIfl manufacturing method for conductive synthetic resin molded articles that can solve the above-mentioned problems.

The method for producing a conductive synthetic resin molded article according to the present invention involves laminating a nonwoven fabric made of conductive fibers on the surface of a base material made of thermoplastic resin sheets 1 to J. Ishikawa's synthetic resin solution with fibers is applied to the surface of the non-woven fabric so that the fluffed portion of the fibers is attached to the same surface, and the synthetic resin liquid of Ishikawa with fibers is prevented from drying. The sheet is set in a molding device and molded into the desired shape.

Examples of the thermoplastic resin constituting the base material include vinyl chloride resin, acrylic resin, 1-tyrene-vinyl acetate copolymer resin, etc. The thickness of the material is usually 0.1 to 3. Qm
It is m. When the base material is thick, a base material containing carbon black inside may be used.

The nonwoven fabric is made of conductive fibers alone or S-conductive fibers and thermoplastic fibers with a low softening point mixed therein, and is produced by a binder method in which the fibers are bonded to form a web using a heat-fused neck of the thermoplastic fibers or a binder. It is manufactured by conventional methods such as needle punching, in which fibers are stitched onto a web using needles without using a binder. Examples of conductive fibers include copper-adsorbing fibers, metal-plated fibers, carbon composite fibers, metal-deposited fibers, thin metal wires, and the like. Furthermore, thermoplastic fibers with a low softening point are made of resins that are compatible with the base material, and examples thereof include various fibers such as polyolefin fibers, nylon fibers, polyester l1rIIj, and acrylic fibers. .

The base material and the nonwoven fabric are bonded together using a roll press method. The pressing temperature is usually around 70°C, and this is appropriately set by Jζ for the base resin.

The synthetic resin solution used for textiles is a solution prepared by dissolving a resin compatible with the base material resin in a solvent, or a 1-mulsion containing the same resin, the viscosity of which is adjusted to 5 to 300 centipoise. The one given is used. Is the viscosity of the same synthetic resin liquid 5L? If it is less than 100 mm, even if the fluffed part of the cloth is pressed against the surface of the nonwoven fabric, the elastic repulsive force of the fibers will overcome the adhesive force of the liquid, so the fibers will stand up again. If the viscosity of the synthetic resin liquid exceeds 300 L/inch voise, the *?IN sheet properties will drop below the required value and the workability of the coating process will deteriorate.

The molding process is carried out by a conventional method using a vacuum molding machine, a pressure molding machine, or the like. However, if the surface of the nonwoven fabric is directed toward the mold, the desired molded product will not be obtained.

As described above, according to the present invention, a synthetic resin liquid for delicate adhesion is applied to the surface of the nonwoven fabric side of a nonwoven fabric pasted sheet, so that the fluffy portions of the ta fibers constituting the nonwoven fabric are pushed onto the surface of the sheet. This eliminates the problems described at the beginning, such as the reduction in S-electroconductivity and the generation of dust due to fiber fragments, and the application of the synthetic resin liquid allows the product to be sealed. The conductivity of 1- does not decrease. The reason for this is not certain, but even after the conductive fibers have been deposited on the surface of the sheet, at least the non-adhered side of the conductive fibers is exposed and the entire surface of the conductive fibers is exposed. It is considered that the coating liquid is not covering the coating liquid. In addition, in the molding process, the surface of the nonwoven fabric side of the conductive sheet is pushed toward the mold, so the formation of JJL bridges on the inside corners of the molded product and the fluffing of J3G on the flat parts, as explained at the beginning, may occur. You can write down.

Next, embodiments of the present invention will be specifically described based on the drawings.

At J3 in FIG. 1, the base material (2) extruded by the sheet 1 to the extrusion molding device (1) is still in a thermally softened state, and the conductive nonwoven fabric (3) is fed out from the roll (13) ) and a nonwoven fabric (3) on one side of the substrate (2) by passing the nonwoven fabric (3) between a pair of pressure loops (4) in an overlapping manner.
are pasted together. The substrate (2) is made of vinyl chloride resin and has a thickness Q of 4111 m. The nonwoven fabric (3) was manufactured by a binder method from acrylic fibers adsorbed with copper and polyethylene fibers.

The temperature of the pressure roll (4) was adjusted to about 70°C. The high temperature seal l-(5) coming out from between the pair of rolls (4) is
Then, it is passed through a plurality of cooling rolls (6) in a jig shape and wound up into a roll.

In this way, 1q of rolls of nonwoven fabric pasted sheet (7) are made.

Next, as shown in Fig. 2, the nonwoven fabric adhesive sheet (7) is fed out from this roll, passed between a plurality of binge rolls (8) with the nonwoven fabric side down, and then passed between a pair of upper and lower applicator rolls. (9).Lower application roll (9)
is in close contact with the coating liquid supply roll (10);
) is immersed in II synthetic resin liquid for adhering miscellaneous materials (11). As a synthetic resin liquid, an acrylic resin solution (manufactured by Mitsubishi Rayon Co., Ltd., product name Acrynal, product number 1-
1-004) with diructone on methyl, the former 6: the latter 4
This is a solution whose viscosity is adjusted to 10L7 indipoise by diluting it at a ratio of In this way, the nonwoven fabric pasted sheet h (7) is passed between the pair of applicator rolls (9), so that about 20 (1/m2) of the synthetic resin liquid is applied to the nonwoven fabric side surface of the sheet (7).
applied. The sheet (7) is then dried while passing through a plurality of take-up rolls (12) to a thickness Q, 4+
A 11111 conductive sheet (13) is wound up into a roll.

When the surface of the nonwoven fabric side of this conductive sheet (13) was observed with a magnifying glass, no fluffing of the conductive fibers was observed. The conductivity was no different from that of sheet (7).

Next, the conductive sheet is cut to a required length, and as shown in FIG. piece (14)
Both ends of the molding device (16) are held between a pair of clamps (17). Next, the sheet piece (14) is a heater (18)
is heated from above at 170°C for 20 seconds. Then, the piece (14) to the sheet 1 in a softened state is vacuum formed to a thickness of 30 mm.
It is molded into a container measuring 0mm x 300mm x 10111111.

When the inside corners and flat parts of the molded container were observed with a magnifying glass, no fiber bridges or fuzz were observed. There was no difference at all.

Comparative Example The operation of the example is repeated, except that the nonwoven side surface of the sheet piece is oriented in the opposite direction of the mold. However, in this case, the mold is a female mold.

As a result of observation using a magnifying glass, fiber bridges were formed on the inside corners of the container, and fiber fluff was formed on the flat portions.

[Brief explanation of drawings]

FIG. 1 and FIG. 2 are process diagrams showing an embodiment of this invention,
FIG. 3 is a vertical sectional view of the vacuum forming apparatus. (2)...Base material, (3)...Nonwoven fabric, (4)...
Pressure roll, (7)...Nonwoven fabric pasting sheet 1-, (9)
... Coating roll, (11) ... Synthetic resin liquid for adhering to paper, (13) ... Conductive sheet, (14) ... Sheet piece, (15) ... Molding mold, ( 16)... Molding device, (17)... Clamp, (1B>... Heater. 4 people other than the above Figure 2 Figure 3 Figure 8)

Claims (2)

[Claims] (1) A nonwoven fabric made of conductive fibers is laminated on one side of a base material made of a thermoplastic resin sheet, and a fluffed portion of the fibers is attached to the nonwoven fabric side surface of the obtained nonwoven stone sheet. Apply the synthetic resin liquid for attaching the m-string and dry. Place the obtained conductive sheet 1 in the molding machine with the nonwoven surface facing the mold. A method for manufacturing a conductive synthetic resin molded product, which is characterized by molding it into a shape. (2) The method according to claim 1, wherein the resin of the synthetic resin liquid is compatible with the resin of the base material. (3) The method according to claim 1 or 2, wherein the synthetic resin liquid has a viscosity of 5 to 300 centipoise.