JPH046907A - Reflecting mirror for parabolic antenna and its manufacture - Google Patents

Abstract

PURPOSE:To form a reflecting mirror for a parabolic antenna having a reflecting mirror surface whose surface state is excellent with excellent conductivity while generation of a flaw and peeling and crack of a conductor layer due to a temperature change are eliminated by using a cloth having the conductor layer and transferring the conductor layer from the cloth to an injection molding body. CONSTITUTION:A synthetic resin injection molding parabolic antenna use reflecting mirror to the reflecting mirror surface of which a conductor layer formed on a cloth is transferred, and a synthetic resin injection molding parabolic antenna use reflecting mirror to the reflecting mirror surface of which a conductor layer formed on a cloth, a top coat layer and ruggedness on the surface of the cloth are simultaneously transferred are offered. Moreover, as the manufacture method, after the cloth having the conductor layer and the top coat layer as required is located in a cavity of a metallic die of the parabolic antenna reflecting mirror so that the conductor layer comes to the resin side, the said metallic die is set, a plasticized synthetic resin is injected and the cloth is peeled from the obtained injection molding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a synthetic resin injection-molded parabolic antenna reflector having a conductive layer (radio wave reflecting layer) transferred to the reflective mirror surface, and a method for manufacturing the same.

[Conventional technology]

With the advent of satellite broadcasting, the demand for parabolic antennas used for this is increasing. Metal materials such as aluminum and copper were often used for the parabolic reflector of this parabolic antenna, but in recent years, plastic plates have been widely used as they are easy to handle, easy to mold, and easy to mass produce. It's starting to feel like it's coming.

However, plastic itself does not have the ability to reflect radio waves efficiently, so when used as a reflector for a parabolic antenna, a conductor layer is installed on the reflective surface to increase radio wave reflection efficiency, which is necessary for reception. It was necessary to add reflective properties. That is, there is a correlation between the radio wave reflection loss and the surface resistance value, and in order to reduce the radio wave reflection loss and improve the radio wave reflection efficiency, the surface resistance value must be lowered and the conductivity must be increased.

Conventional methods for applying the conductor layer include: ■ Spreading metal foil, ■ Applying metal paste (e.g. Cu paste), and ■ Metal paste-coated polyethylene terephthalate (PET) film provided in an injection mold. There is a method of transferring the metal layer from.

(Problem to be solved by the invention) However, in the method (2) above, it is difficult to treat the edges and spread the metal foil uniformly, and the treatment for wrinkles that occur is also complicated. This method was not preferred because of problems such as peeling, wrinkling, and cracking due to the difference in thermal expansion coefficients.

In addition, method (2) involves many steps such as coating, drying, top coating, and re-drying, which inevitably increases costs.In terms of performance, there is also the problem that conductivity is insufficient because the metal particles are coated with a vehicle. there were.

Furthermore, method (2), which is relatively similar to the method of the present invention, also has the problem that the film is easily deformed by the injection pressure, resulting in wrinkles in the transferred conductor layer.On the other hand, when the injection pressure is lowered, the adhesion There was a problem in that the electrical conductivity, which is important, was insufficient.

This method also has the problem that when an engineering resin having a high injection molding temperature is used, the base film is thermally deformed, making it impossible to perform good transfer.

The present invention solves the problems of the conventional methods described above, and provides a synthetic resin injection-molded reflector for parabolic antennas that has a good mirror surface and exhibits excellent conductivity (reflectivity), and a simple and economical manufacturing method thereof. The challenge is to provide this information.

(Means for Solving the Problems) In order to solve the above problems, the inventors of the present invention investigated various transfer techniques in injection molding, and found that they used a fabric having a conductor layer, and transferred the conductor from this fabric to an injection molded body. The inventors have discovered that the above problems can be solved all at once by transferring layers, and have completed the present invention.

That is, the present invention provides a reflective mirror for a synthetic resin injection-molded parabolic antenna in which a conductor layer provided on a cloth is transferred to a reflective mirror surface, a conductor layer and a top coat layer provided on the cloth, and an uneven shape on the surface of the cloth. The present invention provides synthetic resin injection molded reflectors for parabolic antennas, in which the metal is simultaneously transferred to the reflective mirror surface, and a method for producing these includes fabrics having a conductor layer and, if necessary, a top coat layer, with the conductor layer on the resin side. After installing the parabolic antenna reflector in the cavity of the mold so that the reflector looks like this, the mold is set, the plasticized synthetic resin is injected, and the fabric is peeled off from the resulting injection molded product. The present invention provides a method for producing a reflecting mirror for an injection-molded parabolic antenna, in which the surface shape of the above-mentioned cloth, a conductor layer on the cloth, and a top coat layer provided as necessary are simultaneously transferred onto the surface.

The present invention will be explained in detail below.

The fabric used in the present invention may be appropriately selected from commercially available natural, recycled, or synthetic fiber fabrics depending on the purpose, but preferably the type of resin used, especially the resin temperature required for injection, Select by considering conditions such as resin pressure and mold temperature, and performance.

Therefore, most commercially available fabrics are used for general-purpose resins, but natural fabrics are used for engineering plastics that require high temperatures, pressures, and mold temperatures for injection.
It is preferable to use substantially non-thermoplastic fibers such as M-thread, recycled fibers, inorganic fibers, aramid III, acrylic fibers, or m-fiber fabrics with excellent heat resistance.

Most of the generally known lamination methods can be used to form the conductor layer on the fabric, but printing, particularly screen printing, is preferred.

In addition to vapor deposition and sputtering, techniques such as chemical plating, electroplating, ion blating, and etching can also be used depending on the fabric and pretreatment. Further, it is preferable to provide a top coat layer on the conductor layer in order to prevent oxidation and peeling of the conductor layer and improve strength and weather resistance.

In order to apply the top coat layer, prior to applying the conductor layer on the fabric, a commercially available paint for improving weather resistance, such as a two-component urethane type paint or an acrylic paint, is applied to the fabric. This can be done by drying and laminating a conductor layer thereon.

Furthermore, if you want to add a concave-convex pattern such as a logo mark to the surface, attach the concave-convex pattern of the logo mark to the back side of the fabric (the side opposite to the side with the conductor layer/top coat layer) by pasting, etc. Just mold it.

In addition to commercially available conductive inks containing copper, silver, etc., the conductive substances for forming the conductor layer used in the present invention include
Commercially available metal powders such as gold, silver, and copper, or mixtures of conductive substances such as metal flakes and solvent thickeners may be used. In these cases, the metal concentration is preferably relatively high; for example, in the case of copper powder, it is preferably 40% or more.

As the synthetic resin used in the present invention, any synthetic resin conventionally used as an injection molding resin can be used. That is, polyolefin resins such as polypropylene and polyethylene, vinyl chloride resins, PET resins, PC
Resin, polyamide resin, PS, ABS, 1-11 P
In addition to polystyrene resins such as S, polyphenylene ether resins, engineering resins, etc. can also be used.

The following method is used to manufacture the parabolic antenna reflector of the present invention.

First, a mold having the above-mentioned conductor-layered cloth stretched thereon is prepared.

Hot molten resin is extruded into this mold from an extrusion nozzle to fill the mold cavity of the reflector of the parabolic antenna.

When the mixture is then cooled and solidified, a molded article having the above-mentioned cloth attached to the surface is obtained. After or when taking out the molded product from the mold, when the cloth attached to the surface is peeled off, the shape, irregularities, patterns, etc. of the cloth surface are transferred along with the conductor layer and top coat layer provided if necessary. A reflector for a parabolic antenna having excellent reflection characteristics can be obtained.

A conventional method for inserting a plastic film can be used to insert the fabric with a conductor layer. In this case, it is a simple method to attach the fabric to the mold using double-sided tape or the like, or it is also possible to install the fabric by an appropriate mechanical method.

In addition, a commercially available in-mold device may be used.

The fabric can be peeled off from the injection molded article by manual or mechanical methods.

(Function) In the present invention, when hot molten resin is injected into a mold, the resin fills with a part of the cloth placed in the mold being bitten, forming a molded body with the cloth attached to the surface. At this time, the conductor layer is simultaneously fixed to the molded body by the action of heat and pressure, and when the fabric is peeled off, it is transferred onto the molded body.

On the other hand, when conventional plastic sheets are used, they may become wavy due to air flow resistance, transfer and molding may be incomplete due to air pockets, and plastic sheets may soften and deform due to the heat of the injected resin. Otherwise, it often melts.

Furthermore, in the present invention, the conductor layer surface and the injected resin can be brought into contact at a high temperature by utilizing the high injection pressure and the low thermal conductivity of the fabric used, so that the transfer of the conductor layer is possible. The adhesion to the surface is also good, and the electrical conductivity (radio wave reflectivity), which is the greatest feature of the present invention, is greatly improved (the surface resistance of the conductive layer is reduced by about 10-6 times that before transfer). This effect can be obtained. This effect of improving conductivity is due to the above-mentioned transfer under high temperature and high pressure during injection molding.
The vehicle that had wrapped the metal particles in the conductor layer of the cloth selectively penetrated into the cloth, and the remaining bare metal particles were spread out, allowing them to come into close contact with each other. It is assumed that.

(Example) Examples of the present invention are shown below. Example 1 Copper powder (Fukuyama Metal T-Gyo Co., Ltd. Foil FCC115A) and solvent (Teikoku Ink Co., Ltd. Medium ■) were mixed in a weight ratio of 60:4.
A conductive layer was screen printed on a commercially available thin nylon plain weave fabric (manufactured by Asahi Kasei Industries, Ltd.) using a conductive ink mixed with 0.0% conductive ink. This fabric was placed in a mold of a parabolic Ambuna reflector having a diameter of 300 rrm in the form of a paraboloid of revolution using a tape.

Next, a molded article with the fabric attached is obtained by injection molding a boria chlorine ether resin (JFlooZ manufactured by Asahi Kasei Industries, Ltd.) at a resin temperature of 230 to 240°C. When the fabric is peeled from this molded article, A reflective mirror for para-wall cloth with good conductivity (reflectivity) and appearance with a surface resistance of 0.07Ω was obtained.The surface resistance of the conductor layer on the fabric before transfer was IOMΩ. Met.

Example 2 Same as Example 1 except that J-Iron plain woven fabric (manufactured by Asahi Kasei Kogyo) was used, in which a urethane-based two-component type paint was applied on the fabric and the same Cu conductor layer as in Example 1 was provided. It was carried out in the same manner.

A reflecting mirror for a parabolic antenna was obtained, in which a urethane-based top coat having anti-oxidation and weather-resistant coating effects was provided on the reflecting mirror surface on a copper layer.

Example 3 Conducted in the same manner as Example 1 using a fabric with a predetermined logo pattern attached to the urethane top cord layer/copper layer/nylon plain woven fabric laminated fabric used in Example 2. did. A reflecting mirror for a parabolic antenna was obtained, which had a copper layer coated with a urethane top coat on which the logo mark appeared on the reflecting mirror surface.

(Effects of the Invention) The present invention provides synthetic resin injection molding with a reflective mirror surface that has excellent conductivity (radio wave reflection characteristics) and a good surface condition that eliminates the occurrence of wrinkles and peeling and cracking of the conductive layer due to temperature changes. This invention has the effect that a reflector for a parabolic antenna can be provided economically and easily.Furthermore, the present invention also allows the application of a topcoat 1~ and a logo mark, etc., on the anti-mirror surface in an extremely simple and economical manner at the same time as applying a conductor layer. There is also the effect of being able to do it.

Claims (1)

[Claims] 1. A synthetic resin injection-molded parabolic antenna reflector, in which a conductor layer provided on cloth is transferred to a reflective mirror surface. 2. Reflection for synthetic resin injection molded parabolic antenna in which the conductor layer and top coat layer provided on the cloth and the uneven shape of the surface of the cloth are simultaneously transferred to the reflective mirror surface. 3. The reflector for a parabolic antenna according to claim 2, wherein the uneven shape on the surface of the fabric is a logo mark. 4. The reflector for a parabolic antenna according to claim 1, 2 or 3, wherein the conductor layer is made of copper or silver. 5. After placing the fabric having a conductive layer and, if necessary, a top coat layer, in the cavity of a mold for a parabolic antenna reflector so that the conductive layer is on the resin side, the mold is set and the plasticized composite is placed. The surface shape of the fabric, the conductor layer on the fabric, and the top coat layer provided if necessary are simultaneously transferred to the surface by injecting the resin and then peeling the fabric from the obtained injection molded product. A method for manufacturing a reflector for an injection-molded parabolic antenna. 6. A urethane top coat layer is provided on the fabric,
6. The method for manufacturing a reflector for a parabolic antenna according to claim 5, wherein a fabric is used, on which a conductor layer made of copper or silver is laminated. 7. The method for manufacturing a reflector for a parabolic antenna according to claim 5 or 6, characterized in that a fabric having a concavo-convex shape of a logo mark attached to the back surface is used.