JPS60246105A - Reflecting plate for circularly polarized wave antenna - Google Patents

Abstract

PURPOSE:To obtain a reflecting plate with excellent corrosion resistance whose radio wave reflecting characteristic is unchanged for a long period by forming the reflecting plate through the sequential lamination of a thermoplastic resin layer having at least excellent weather resistance, a kind of forming material selected among a metallic mat, cloth and net and a polyvinyl chloride group polymer layer including an inorganic filler. CONSTITUTION:The thickness of the thermoplastic resin layer 3 is 5mu-5mm., the metallic forming material is finner than 2 meshes, the thickness of the polyvinyl chloride group polymer layer including an inorganic filler is 500mu-15mm. and the content of the inorganic filler of this layer is 10-80wt%. As a typical example of the thermoplastic resin 3, ethylene, propylene, or vinylidene fluoride is used. As a typical example of the metal 2, a metal such as aluminum, iron, nickel, copper or zinc is used. The polyvinyl chloride group polymer 1 is a vinyl chloride homopolymer and a copolymer of vinyl chloride and at most 50wt% (preferably <=45wt%) compound having at least one double bond and capable of copolymerizing with vinyl chloride.

Description

[Detailed Description of the Invention] [I] Object of the Invention The present invention provides a laminate having as an intermediate layer at least one shaped object selected from the group consisting of metallic mats, cloths and nets, which are radio wave reflecting layers. The present invention relates to a reflector for a circularly polarized antenna. More specifically, at least (A)
Thermoplastic resin layer with good weather resistance (B) metallic mat,
At least one shaped object selected from the group consisting of cloth and net (C) A laminate formed by sequentially laminating inorganic filler-containing vinyl chloride polymer layers, and the thickness of the thermoplastic resin layer is 5 microns. The metal cloak, cloth and net are finer than 2 meshes, and the thickness of the vinyl chloride polymer layer containing inorganic filler is 500 microns to 15 m thick, and the inorganic filler in this layer This invention relates to a reflector for a circularly polarized antenna, characterized in that the content of be.

[II] Background of the Invention Satellite broadcasting such as high-definition television broadcasting, still image broadcasting, single character multiplex broadcasting, PCM (Pulse Code Modulation) audio broadcasting, and facsimile broadcasting using static 1F satellites is available in countries around the world such as Europe, America, and Japan. Its practical application is planned in the near future. However, since a geostationary satellite has only one orbit, there is a risk of interference between multiple broadcast radio waves. In order to avoid such mutual interference of broadcast waves, it is necessary to utilize cross-polarization identification of satellite broadcast receiving antennas. In this way, when receiving terrestrial broadcast waves, the radio waves are linearly polarized horizontally or vertically, and the polarization plane of the receiving antenna is matched to the polarization plane of the broadcast waves, using cross-polarization discrimination. However, when receiving radio waves from a broadcasting satellite, the polarization plane shifts due to disturbances caused by the ionosphere in the radio wave propagation path and the angle of incidence of the radio waves at the receiving point, so the above-mentioned method is not possible. Match the polarization planes like this.

It is difficult to do so.

Frequency allocation to multiple broadcasting satellites is considered to be done by taking polarization plane discrimination into consideration from the point of view of effective use of satellite broadcasting radio frequency bands. In this case, the quality of the polarization plane adjustment of the receiving antenna directly determines the level of interference between broadcast channels, so if the broadcast satellite radio waves are linearly polarized, it cannot be expected to obtain a high degree of cross-polarization discrimination. . However, when broadcasting satellite radio waves are circularly polarized waves, it is easy for ordinary listeners to identify them by the direction of travel of the circularly polarized waves, regardless of the deviation of the plane of polarization as described above. The receiving antenna not only adjusts its pointing direction to point to the desired broadcasting satellite, but also does not require adjustment of the plane of polarization, making it much easier to adjust the receiving antenna than when linearly polarized waves are used. Therefore, it is possible to obtain the degree of polarization discrimination as designed for the receiving antenna.

For these reasons, plans are being made to use circularly polarized waves for broadcast satellite radio waves in future satellite broadcasting systems. In contrast, conventional circularly polarized antennas include those that use a conical horn, those that combine two Gui balls at right angles, and parabolic antennas that use these antennas as the primary radiator. The structure is complex and large, and manufacturing costs are high, so it is not suitable for general audience receiving antennas for receiving satellite broadcast radio waves using microwaves in the 12 gigahertz (G&) band. do not have.

On the other hand, the structure is extremely simple, and as a small and lightweight microwave antenna, a rectangular waveguide is extended in the axial direction from the center of a parabolic reflector, and its tip is curved so that the opening end surface becomes a parabolic shape. There is a so-called Heehat-type parabolic antenna that faces a parabolic reflector at its focal point and uses this as a -order radiator. This antenna is widely used in microwave antennas for mobile relays, etc., but all conventional Hehat-type parabolic antennas now transmit and receive linearly polarized waves using short waveguides as described above. Therefore, it cannot be used for solar polarization.

Generally, metal plates or metal nets have been used as parabolic antennas. However, since metals corrode, it is necessary to use anti-corrosion alloys or apply anti-corrosion coatings. If anti-corrosion alloys are used, they are expensive. On the other hand, even if anti-corrosion coating is applied, it is necessary to repeat the coating several times to achieve complete corrosion protection, which not only makes it expensive, but also causes the problem that the coated object deteriorates after being used for many years. . Furthermore, attempts have been made to manufacture radio wave reflecting plates in which glass fibers with metallized surfaces are laminated to thermosetting resins such as unsaturated polyester resins as radio wave reflecting layers, but the manufacturing method is complicated and It has been extremely difficult to maintain the radio wave reflective layer at a constant thickness and without unevenness.

[I11] Structure of the Invention Based on the above, the inventors have created a reflector for a circularly polarized antenna that has a φ-pure manufacturing process, has radio wave reflecting ability, and can maintain its performance for a long period of time. As a result of various searches for obtaining at least - (A) a thermoplastic resin layer with good weather resistance; (B) "at least one shaped object selected from the group consisting of metallic mats, cloths, and nets";
(Hereinafter referred to as "metallic shape") (C) A laminate formed by sequentially planting inorganic filler-containing vinyl chloride polymer layers, and the thickness of the thermoplastic resin layer is 5 microns to 511I+1. The metal shape is finer than 2 meshes, and the thickness of the inorganic filler-containing vinyl chloride polymer layer is 500 microns to 15 microns, and the inorganic filler content in this layer is 10 to 80 microns. The inventors have discovered that a reflector for a circularly polarized antenna, which is characterized by a heavy 100% strength, not only has good durability, but also has excellent radio wave reflection characteristics, and has thus arrived at the present invention.

[IV] Effects of the Invention The circularly polarized antenna reflector of the present invention exhibits the following effects (features) including its manufacturing process.

(+) Excellent corrosion resistance, so there is no change in radio wave reflection characteristics over a long period of time.

(2) Since the coefficient of linear expansion of the inorganic filler-containing vinyl chloride polymer layer is extremely small, no peeling occurs between the layers even if subjected to heat cycles (repetition of cold and heat) for a long period of time.

(3) The reflector for a circularly polarized antenna is lightweight and the manufacturing process is simple.

(4) It is possible to form a metallic object uniformly, and there is no uneven reflection of radio waves.

(5) Vinyl chloride-based polymers containing inorganic fillers can be easily formed into various complicated shapes, and therefore have good appearance and functionality.

(6) The mechanical strength (especially rigidity) of the circularly polarized antenna reflector is excellent.

[V] Detailed description of the invention (A) Thermoplastic resin The thermoplastic resin used to manufacture the thermoplastic resin layer of the present invention is widely produced industrially and used in many fields, Their manufacturing methods and various physical properties are well known. Their molecular weight varies depending on the type, but generally ranges from 10,000 to 1,000,000. Typical thermoplastic resins are homopolymers of monomers having double bonds such as ethylene, propylene, vinylidene fluoride, vinyl chloride, and styrene, which are the main components (at least 50% by weight). Copolymer, copolymer of styrene and acrylonitrile (
AS resin), resin whose main component is methyl phthalate (I
IIMA resin), butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber (NBR), styrene-
Butadiene copolymer rubber (SBR), acrylic rubber, ethylene-propylene copolymer rubber (EPR), ethylene-propylene-diene ternary copolymer rubber (EPD)
and graft copolymer resins obtained by graft copolymerizing vinyl chloride alone or styrene and other vinyl compounds (e.g., acrylonitrile, methyl methacrylate) to rubber such as chlorinated polyethylene;
Mention may be made of polyamide resins, polyester resins, polyphenylene oxide resins and polycarbonate resins. Furthermore, even if these thermoplastic resins are modified by grafting an organic compound having at least one double bond (for example, an unsaturated carboxylic acid or its anhydride), they have excellent processability. You can use it if you like. Furthermore, in addition to the graft copolymer resins described above, compositions obtained by blending the above-mentioned rubbers with these thermoplastic resins (the blending ratio of rubber is generally at most 40% by weight) can also be used.

Among these thermoplastic resins, fluorine-containing resins such as polyvinylidene fluoride are preferred because of their excellent weather resistance. Furthermore, even with vinyl chloride-based resins, ethylene and/or propylene-based resins, the weather resistance of these formulations can be improved by adding UV absorbers. You can use it as you like. Furthermore, polyamide resins, polyester resins and polycarbonate resins can also be used. Among these thermoplastic resins, organic compounds (especially, It is advantageous to use a modified resin obtained by graft polymerization of an unsaturated carboxylic acid and its anhydride (preferably an unsaturated carboxylic acid and its anhydride), in part or in whole, because it has excellent adhesion to the metallic shape described below.

(B) Metal Furthermore, typical examples of metals that are raw materials for the metallic shapes in the present invention include simple metals such as aluminum, iron, nickel, copper, and zinc, and alloys containing these metals as main components (for example, stainless steel, brass). These metals do not need to be surface-treated, and may be previously subjected to surface treatment such as chemical treatment or plating treatment. Furthermore, those that have been painted or printed can also be preferably used.

(C) Vinyl chloride polymer The vinyl chloride polymer used to produce the inorganic filler-containing vinyl chloride polymer layer in the present invention is
Vinyl chloride homopolymer and vinyl chloride and at most 50
The degree of polymerization of this vinyl chloride polymer, which is a co-backing polymer with a compound having at least one double bond that can be copolymerized with vinyl chloride in a weight percent (preferably 45 weight percent or less), is usually 400 to 4500. , particularly preferably 400 to 1500. Typical examples of compounds having this double bond at least 1 (Pl) include vinylidene chloride, ethylene, propylene, vinyl acetate, acrylic acid and methacrylic acid and their esters, maleic acid and their esters, and acrylonitrile. These vinyl chloride polymers are obtained by homopolymerizing or copolymerizing vinyl chloride alone or vinyl chloride and the above-mentioned vinyl compound in the presence of a free radical catalyst, and the manufacturing method is widely used. It is used in many ways.

In producing the inorganic filler-containing vinyl chloride polymer of the present invention, only the vinyl chloride polymer may be used as the polymer material, but other types of polymers that are miscible with the vinyl chloride polymer may be used. Substances may also be blended. The polymer substance has a molecular weight of 10,000 to 1,000,000 (preferably 1,000,000).
Ethylene homopolymer (100,000 to 100,000) or copolymer of ethylene and α-olefin having 3 to 12 carbon atoms (
Chlorinated polyethylene rubber (chlorine content is usually 25 to 45% by weight) obtained by chlorinating α-olefin copolymer (usually at most 20 mol%), ethylene-propylene-diene ternary rubber Polymerized rubber (EPD)
M), natural rubber, chloroprene rubber, chlorosulfonated polyethylene rubber, styrene-butadiene-
Rubbery products such as butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber (NBR), and butadiene homopolymer rubber [generally, Mooney viscosity (ML, +4) is 10 to 1501] .

These rubber-like substances are well-known in books such as ``Synthetic Rubber Handbook'' edited by Kambara et al. (Breakfast Shoten, published in 1962) and ``Plastic Handbook'' edited by Shitachi et al. (Breakfast Shoten, published in 1964). It is something that exists.

When these other types of rubbery materials are blended, their blending ratio is at most 50% by weight relative to the vinyl chloride polymer.

(D) Inorganic filler The inorganic filler used to produce the inorganic filler-containing vinyl chloride polymer layer is generally one widely used in the fields of synthetic resins and rubber. These inorganic fillers are preferably inorganic compounds that do not react with oxygen and water, and that do not decompose during crosstalk or molding. The inorganic fillers include metals such as aluminum, copper, iron, lead and nickel;
Compounds such as oxides of these metals and metals such as magnesium, calcium, barium, zinc, zirconium, molybdenum disilicon, antimony, and titanium, their hydrates (water oxides), sulfates, carbonates, and silicates. , these double salts, and mixtures thereof. Typical examples of the inorganic fillers include the metals mentioned above, aluminum oxide (alumina), water products thereof, calcium hydroxide, magnesium oxide (magnesia), magnesium hydroxide, zinc oxide (zinc white), red lead, and white lead. Lead oxides, magnesium carbonate, carbonic acid 11, +! monobasic magnesium carbonate white carbon, asbestos, mica, talc, glass fiber, glass powder, glass peas,
Clay, diatomaceous earth, silica, wollastonite, iron oxide, antimony oxide, titanium oxide (titania), lithopone, rock powder, aluminum sulfate (gypsum, etc.), zirconium silicate, zirconium oxide, barium carbonate, dolomite, molybdenum disulfide, and Iron sand can be given. Among these inorganic fillers, those in powder form preferably have a diameter of 1111 m or less (preferably 0.5 mm or less). Also r
The am-shaped one has a diameter of 1 to 500 microns (preferably 1 to 300 microns) and a length of 0.11 to 8 microns.
A (preferably 0.1 to 5 mm) is desirable,
Furthermore, it is preferable that the diameter of the flat plate be 2 square inches or less (preferably 1 square inch or less).

(E) Structure of each layer (1) Thermoplastic resin layer The thermoplastic resin layer of the present invention functions to prevent the occurrence of corrosion of metallic shapes as described later.

From this, the thickness is 5 microns to 5 cm, and 1
0 micron to 5 mm is preferred, particularly 10 micron to lff1w. If the thickness of this thermoplastic resin layer is less than 5 microns, not only will the metal shape be corroded, but it will also suffer from contact with other articles during use.
There is a problem in that the metal shape may be exposed due to wear due to friction. On the other hand, if it exceeds 5 cm, it is not preferable because it not only lowers the reflectance of radio waves but also increases the cost and weight of the laminate.

(2) Metallic shaped article The metallic shaped article of the present invention can be made into a mat by fabricating the metal fibrous article described above by methods such as plain weaving, twill weaving, tatami weaving, 5t#A, twisted cotton weaving, triple weaving, and clamp weaving. , woven or braided in the form of a cross or net. #! For female animals, the diameter is usually 0.0020 to 1 mm, preferably 0.0050 to 0.5+am, and particularly preferably 0.01 to 0,3+++a.

Among these, those made of knitted steel wires are preferred because they have elasticity in the vertical and horizontal directions. The diameter of the fibrous material is 0.002
If it is less than 0 mm, it is difficult to process it into matte, cross or net shapes. On the other hand, if the diameter exceeds Ims+, not only will the weight increase, but the cost will also increase, and problems arise when the laminate is curved, bent, etc. The size of the mesh of this metallic shape is important in determining the radio wave reflection performance. The size of the mesh is smaller than 2 meshes, preferably smaller than 4 meshes, and particularly preferably smaller than 8 meshes. If a metallic object with a rougher shape than 2 meshes is used, the reflectance of circularly polarized waves will be significantly reduced.

(3) Inorganic filler-containing vinyl chloride polymer layer The composition ratio of the inorganic filler in the inorganic filler-containing vinyl chloride polymer layer of the present invention is 10 to 80% by weight (i.e., vinyl chloride polymer layer). The composition ratio of the combination is 90-20%), 1
0 to 70% by weight is preferred, particularly 10 to 60% by weight. If the composition ratio of the inorganic filler in the inorganic filler-containing vinyl chloride polymer layer is less than 10% by weight, the linear expansion coefficient of the inorganic filler-containing vinyl chloride polymer layer will be different from that of the metallic shape. In addition, there is a problem that not only peeling may occur between the metallic shape and the inorganic filler-containing vinyl chloride polymer layer due to heat cycling, but also that the resulting laminate lacks rigidity. on the other hand,
If it exceeds 80% by weight, it will be difficult to produce a uniform composition, and even if a uniform composition is obtained, it will be difficult to produce a laminate by sheet production or injection molding as described below. , it is not possible to obtain a good product (laminate).

The thickness of this inorganic filler-containing vinyl chloride polymer layer is 50 mm.
0 micron to +5 an, preferably 1 to 10a111, especially 1 to ? ■ is preferred. If the thickness of the inorganic filler-containing vinyl chloride polymer layer is less than 500 microns, it is undesirable because it lacks rigidity and is deformed and damaged by external force. On the other hand, if it exceeds 15 mm, it will take time to cool down during molding, and not only will sink marks be more likely to occur on the surface, but the weight will increase, causing problems in use.

In producing the thermoplastic resin layer and the inorganic filler-containing vinyl chloride polymer layer, stabilizers against oxygen, heat and ultraviolet rays, metal deterioration inhibitors, flame retardants, and plasticizers commonly used in the respective fields are used. agent, dehydrochlorination inhibitor, colorant, electrical property improver, antistatic agent, lubricant,
Additives such as processability improvers and tackiness improvers may be added to the extent that they do not impair the properties of the compositions of the thermoplastic resin layer and the inorganic filler-containing vinyl chloride polymer layer of the present invention.

When blending the above-mentioned additives into the thermoplastic resin of the present invention and when producing an inorganic filler-containing vinyl chloride polymer (including cases where the above-mentioned additives are blended), the additives commonly used in the respective industries are used. It may be triblended using a mixer such as a Henschel mixer, or may be obtained by melt-kneading using a mixer such as a Banbury mixer, Niegoo, roll mill, or screw extruder. At this time, a homogeneous composition can be obtained by triblending in advance and melt-kneading the resulting composition (mixture).

In particular, it is preferable to use the vinyl chloride polymer in the form of powder because it allows for more uniform mixing.

In this case, the mixture is generally melt-kneaded and then molded into pellets, which are then subjected to the molding described later.

In producing the inorganic filler-containing vinyl chloride polymer of the present invention, all the ingredients may be mixed at the same time, or some of the ingredients may be mixed in advance to produce a so-called masterbatch, and the resulting master The batch and remaining formulation ingredients may be mixed.

When melt-kneading is carried out to produce the above-mentioned blends, it must be carried out at a temperature higher than the melting point or softening point of the thermoplastic resin or vinyl chloride polymer used, but if carried out at high temperatures, the thermoplastic resin and Vinyl chloride polymer deteriorates. For these reasons, the temperature is generally 20°C higher than the melting point or softening point of the respective thermoplastic resin or vinyl chloride polymer (preferably, a temperature higher than 50°C), but does not cause deterioration. Performed over a temperature range.

(F) Reflector for Circularly Polarized Antenna The reflector for circularly polarized antenna of the present invention will be explained below with reference to FIGS. 1 to 3. FIG. 1 is a partial perspective view of an antenna to which a reflector for a circularly polarized antenna is attached. FIG. 2 is a sectional view of the reflector for the circularly polarized antenna. Also, the third
The figure is a partially enlarged view of the sectional view. In FIG. 1, A is a reflector for a circularly polarized antenna of the present invention, B is a converter, C is a converter support rod, and D is a reflector support rod. Further, E is a wiring. Also.

In Figure 2, the material is a laminate in which a thermoplastic resin layer with excellent weather resistance, a primer layer, a metal shape, and a primer layer are laminated in sequence (either or all of these primer layers are not present). ), II
is a vinyl chloride polymer layer containing an inorganic filler.

Furthermore, in FIG. 3, 1 is an inorganic filler-containing vinyl chloride polymer layer, and 2 is a metallic shape. Also,
3 is a thermo-al plastic resin layer with excellent weather resistance. Further, 2a and 2b are single layers of primer. As is clear from these drawings, the feature of the reflector for a circularly polarized antenna of the present invention is that it has a structure consisting of at least three layers. In addition, the reflection plate for a circularly polarized antenna of the present invention has excellent adhesion between the thermoplastic resin layer and the metallic object, which has excellent weather resistance, and between the metallic object and the inorganic filler-containing olefin polymer layer. A primer can also be used to harden. Further, in order to attach the reflector for a circularly polarized antenna of the present invention to a support, the reflector may be attached with ribs so that it can be attached to the vinyl chloride polymer layer containing an inorganic filler. You can also add a reinforcing lip to strengthen it. Furthermore, it is also possible to drill holes in the support for a circularly polarized antenna obtained by the present invention, and attach various support attachment parts using bolts, nuts, etc. Further, the diameter of the reflector for the circularly polarized antenna is usually EtOcm to 120C1.

(G) Method for manufacturing a reflector for a circularly polarized antenna The reflector for a circularly polarized antenna of the present invention is produced by manufacturing a metal shape that is laminated in advance, and then using the laminated metal shape by a vacuum forming method. , a pressure molding method, a stamping molding method, an injection molding method, or the like. Manufacturing methods using these molding methods will be explained in more detail.

(1) Method for manufacturing a laminated metallic object In the present invention, laminating a thermoplastic resin onto the metallic object can be achieved by applying a commonly practiced method. below,
The method will be explained in detail.

The method of laminating (adhering) the thermoplastic resin layer with excellent weather resistance and the metallic shape can generally be carried out by the tri-lamination method, but it is possible to carry out the method by extruding at high temperature in a thermoplastic resin. For vinyl chloride polymers that are capable of this, the thermoplastic resin layer and the metallic shape can be laminated (adhered) by extrusion lamination. To manufacture laminated metal shapes using the extrusion lamination method, use a T-gui film molding machine at a resin temperature of 240 to 370°C.
It is sufficient to extrude it to the above-mentioned thickness at a temperature range of 200 to 3000, and at the same time bond it to a metal shape using a cooling pressure roll.

When using a thermoplastic resin that has excellent adhesion to a metallic shape, a laminated metallic shape can be produced as described above. However, when using a thermoplastic resin whose adhesion to metallic objects is not fully satisfactory, a primer (anchor coating agent) commonly used in the field of thermoplastic resins is applied in advance to the metallic object. It is applied to one side of the object by gravure coating method or perspective coating method and dried at 50 to 100°C. Next, a thermoplastic resin film or sheet is pressed onto the surface of the primer of the metallic shape using a pressure roll heated to 50 to 100°C. The primer differs depending on the type of thermoplastic resin used to form the thermoplastic resin layer, but it is commonly used in various fields, and there are aqueous types and solvent types. The types include vinyl, acrylic, polyamide, epoxy, rubber, urethane, and titanium.

(2) Production by vacuum forming or pressure forming When extruding a filler-containing vinyl chloride polymer into a sheet by the T-Guy molding method,
By laminating on one side, a laminate can be obtained in which a thermoplastic resin layer with excellent weather resistance, a metallic shape, and a vinyl chloride polymer layer containing an S filler are sequentially laminated. The laminate (sheet) obtained in this way is fixed with iron cotton or claw-like objects, placed in a jig that is easy to handle, and heated with ceramic heaters or sheathed wire heaters arranged vertically. Pull it into a device that can heat it. When the sheet is heated, it begins to melt, but at that time, the sheet begins to sag, and then as the heating continues, it stretches inside the wafer that is holding it down. When this stretching phenomenon is observed, the best timing for sheet molding is when the molded product is in a good heating state without wrinkles or uneven thickness. At this time, the desired molded product is obtained by pulling out the sheet work, placing it on the upper part of the mold, and performing vacuum forming from the mold side under a reduced pressure of one atmosphere. Then, the product is cooled by wind or water spray and released from the mold.

On the other hand, in compressed air forming, the sheet that is easier to mold is pulled out to the top of the mold, a chamber (box) for compressed air is placed over the sheet, and the sheet is pressed against the mold side with a pressure of 3 to 5 atm. A molded product can be obtained by pushing up the mold together with the mold.

In addition, in any molding method, the surface temperature is 150 to 200℃.
℃ is the preferred temperature.

(3) Manufacturing by stamping molding method To manufacture the circularly polarized antenna reflector of the present invention by this method, the weather-resistant A laminate sheet in which a superior thermoplastic resin layer, a metallic shape, and an inorganic filler-containing vinyl chloride polymer layer are sequentially laminated is introduced into a drawing die attached to a vertical pressing machine, and then 5 to 50 k
g/cm' (preferably 10-20 kg/c
The desired molded product can be obtained by heating and pressing under a pressure of m'). The product is then obtained by cooling with air or water spray and releasing from the mold. During molding, the pressurizing time is usually 15 seconds or more, typically 15 to 40 seconds. Further, in order to improve surface properties, it is preferable to perform molding under two-step pressure conditions. In this case, after applying pressure for 15 to 40 seconds under a pressure of 10 to 20 kg/crn' in the first stage, 40 to 50 kg/crn' is applied in the second stage.
A molded product with excellent surface smoothness can be obtained by applying pressure for 5 seconds under a pressure of J/cm".Especially when using a vinyl chloride polymer layer containing an inorganic filler with poor fluidity. This two-stage molding method is desirable.The molding temperature in the stamping molding method is such that the surface temperature is 130 to 1
A preferred temperature is 80°C.

(4) Manufacture by injection molding method In order to manufacture the reflector plate for a circularly polarized antenna of the present invention by injection molding method, a thermoplastic resin layer with excellent weather resistance is laminated on one side in advance, and a primer layer is placed on the other side. Insert injection molding is carried out when molding a reflector plate for a circularly polarized antenna.To carry out insert injection molding, the metal shape is inserted into the male and female molds of an injection molding machine. (Insert the thermoplastic resin layer between the molds so that the weather-resistant thermoplastic resin layer faces toward the bottom) and close the mold. Thereafter, the vinyl chloride polymer containing an inorganic filler is filled into the mold through the gate of the mold, and after cooling, the mold is opened to obtain the desired reflector for a circularly polarized antenna. . For insert injection molding, the resin temperature is higher than the melting point of the vinyl chloride polymer containing an inorganic filler, but lower than the thermal decomposition temperature of the vinyl chloride polymer. Insert injection molding is preferably carried out at a temperature range of lft0 to 200°C, and if the injection pressure is 40 kg/crn' or higher at the nozzle part of the cylinder of the injection molding machine, the injection molding process must be carried out using vinyl chloride containing an inorganic filler. Not only can the system polymer be shaped into a shape almost similar to the shape of the mold, but also a product with good appearance can be obtained. The injection pressure is generally 40 to 140 kg/cm', preferably 70 to 120 kg/cm'.

[VI] Examples and Comparative Examples The present invention will be explained in more detail with reference to Examples below.

In the Examples and Comparative Examples, the radio wave reflectance was measured as a microwave reflection coefficient based on the voltage standing wave ratio when a rectangular waveguide was used and the tip of the waveguide was short-circuited. In addition, the weather resistance test was conducted using a Sunshine Carbon Weathermeter under the conditions of a black hole temperature of 83°C and a due cycle of 12 minutes/(60 minutes of irradiation).
Appearance of surface after time (detrimental changes such as discoloration, fading, gloss, crazing, blistering, peeling of metal shapes, cracks, etc.)
was evaluated. Furthermore, the heat cycle test exposed the sample to 80°C for 2 hours and then to 45°C for 4 hours.
temperature, exposed to this temperature for 2 hours, and then gradually heated to 80°C over 4 hours, repeating this cycle for 1 time.
After conducting the test 00 times, the appearance of the surface of the sample was evaluated in the same manner as in the weather resistance test. Peel strength was measured by cutting a test piece with a width of 15°C from a manufactured reflector for a circularly polarized antenna, and peeling it off at a peeling rate of 50 mm/min based on ASTl'l D-903. The strength was evaluated when it was peeled off at 180 degrees.

Additionally, bending stiffness was measured according to ASTM 0-7130 and coefficient of thermal expansion was measured according to ASTM D-898.

In addition, the heat + ITg used in the examples and comparative examples
The types and physical properties of the thermoplastic resin, vinyl chloride polymer, inorganic filler, and metallic shape of the plastic resin layer are shown below.

[(A) Thermoplastic resin As a thermoplastic resin, the melt flow rate (ASTM
D-1238N, polyvinylidene fluoride (hereinafter referred to as PVdFJ) with a capacity of 8.1 g/10 minutes (measured at a temperature of 250°C and a load of 10 kg),
0.4% by weight of benzotriazole-based ultraviolet absorber
and propylene homopolymer containing 0.5% by weight of carbon blur [melt flow index (JI
According to S K-6758, measured at a temperature of 230°C and a load of 2.16 kg, 0.5 g/10 minutes (hereinafter referred to as MFIJ), benzotriazole-based ultraviolet rays Absorbent at 0.4% by weight and 0.4% by weight. ! High density polyethylene containing 43% carbon black [density 0.958 g/cr
n', melt index (according to JIS K-8760, temperature is 1!30℃ and load is 2.18kg)
Measured under the following conditions: rM, 1. ) is 0.8g
/10 minutes, hereinafter referred to as ``HDPE (1)''] A mixture of chlorinated polyethylene (chlorine content 3.15% by weight, amorphous, with Mooney viscosity (ML, +4) of 108)
20 parts by weight of raw material polyethylene (molecular weight approximately 200,000) and 80 parts by weight of acrylonitrile-styrene copolymer resin (
Acrylonitrile content: 23% by weight) and 2 parts by weight of dibutyltin malate stabilizer (manufactured by Sankyoki Gosei Co., Ltd., trade name: Stann BN)
was kneaded for 10 minutes using a roll (surface temperature 180°C), and the resulting composition (hereinafter referred to as rACSJ)
and 20 parts by weight of dioctyl phthalate (as a plasticizer) and 5.0 parts by weight of dibutyltin maleate (as a dehydrochlorination inhibitor) with 100 parts by weight of vinyl chloride homopolymer [degree of polymerization +100. Hereinafter, a mixture blended with r PVC (referred to as υJ) was used.

[(B) Vinyl chloride polymer] Vinyl chloride homopolymer having a degree of polymerization of about 820 as a vinyl chloride polymer c or less rpvC(2)J 1
, a copolymer of vinyl chloride and vinyl acetate [vinyl content 15% by weight, degree of polymerization approximately 810, hereinafter referred to as rPVC (3
)J] and chlorinated polyethylene rubber (chlorine content: 30.0%) obtained by chlorinating an ethylene polymer with a molecular weight of about 120,000 (density: 0.9413/cm") using an aqueous suspension method. 2% by weight) to 5 parts by weight and 1
00 parts by weight of PVC (2)" [hereinafter "
Mixture (A)] was used.

[(C) Inorganic filler] As the inorganic filler, talc with an average particle size of 3 microns (aspect ratio of about 7), mica with an average particle size of 3 microns (aspect ratio of about 8), glass fiber (single # Calcium carbonate (hereinafter referred to as rcacO3J) having an average particle size of 0.8 microns was used.

[(D) Metallic shapes: 40 mesh plain woven wire cloths made of aluminum (hereinafter referred to as "rAJl"), copper, brass and silver, each having a fiber diameter of about 0.3cm, were used as metallic shapes. used.

Examples 1 to 12, Comparative Example 1.2 The thermoplastic resin was molded to produce films each having a thickness of 20 microns. In addition, an acrylic primer (manufactured by Showa Kobunshi Co., Ltd., trade name Vinyroll 92T) was applied to one side of each metal shape to a thickness of 20 microns, and a urethane primer (Toyo Morton Co., Ltd.) was applied to the other side. (trade name: ATOCOTE 335) manufactured by ATOCOTE, Inc., was applied to a thickness of 20 microns on each surface and dried (in Examples 7 and 10, the urethane-based primer was applied on both sides). Furthermore, an inorganic filler and a vinyl chloride polymer (30 parts by weight of dioctyl phthalate as a plasticizer per 100 parts by weight of the vinyl chloride polymer) (DOP) and 25 parts by weight of dibenzyl phthalate and desalinated Contains 3 parts by weight of tribasic lead sulfate and 1 part by weight of monobasic lead stearate as a hydrogen preventive 1F agent, the type of each inorganic filler and vinyl chloride polymer, and the content of the inorganic filler in the composition. The rates are shown in Table 1. In addition, in the comparative example, each mixture (without inorganic filler) was tri-blended using a Henschel mixer for 5 minutes, and each mixture was manufactured into a composition using a vented extruder at a resin temperature of 190 ° C. did. A sheet having a thickness of 2H was manufactured from each of the obtained compositions (pellets) using a T-Guy molding machine.

The thermoplastic resin film produced in this manner (not used in Comparative Example 1), a metallic shape coated with a primer on both sides, and a vinyl chloride polymer sheet containing an inorganic filler were used. The laminate was manufactured by adhering by dry lamination method. The obtained laminate was vacuum formed using a bowl-shaped female mold (outer diameter 750 mm, height 80+ am) under conditions of 170"O (surface temperature of the laminate) to form a circularly polarized antenna. Reflector plates were manufactured (Examples 1, 2.7 to 12, Comparative Example 1)
, 2), laminates produced in the same manner as in Examples 1 and 2 (types of inorganic fillers and vinyl chloride polymers, content of inorganic fillers in the composition, and types of metallic shapes, (shown in Table 1) when the surface temperature is 13
Under the condition of 5℃, the first stage is under a pressure of 20 kg/cm' for 0 seconds, and the second stage is under a pressure of 50 kg/cm' for 20 seconds.
Stamping molding was performed in one step by holding the sample for 5 seconds (the shape of the mold was the same as in Example 1) to produce a reflector for a 5-day polarized antenna (Examples 3 and 4).

After applying the above acrylic primer to one side of each metal shape whose type is shown in Table 1 to a dry thickness of 20 microns, apply each thermoplastic resin whose type is shown in Table 1. film (20 microns thick) was laminated. A urethane primer was applied to the other surface of the obtained laminate in the same manner as in Example 1. Each coated laminate thus obtained was inserted into an injection molding machine (clamping force 1500 m) so that the thermoplastic resin film was in contact with the male mold surface of the mold. After closing the mold, the injection pressure is 80kg/cm' and the resin temperature is 180°C.
Under the following conditions, insert injection molding was performed using the composition whose types of vinyl chloride resin and inorganic filler and the content of the inorganic filler in the composition are shown in Table 1.
A circularly polarized antenna reflector having the same shape as Example 1 was manufactured (Example 5.6).

The elastic modulus and linear expansion coefficient of the inorganic filler-containing vinyl chloride polymer layer of each circularly polarized antenna reflector obtained as described above, as well as the metal The peel strength of the shaped objects was measured. The results are shown in Table 1.

(The following is a blank space) When the radio wave reflectance of each circularly polarized antenna reflector obtained as described above was measured, it was 98%. Furthermore, weather resistance tests and heat cycle tests were conducted, but no harmful changes such as discoloration, fading, change in gloss, crazing, blistering, peeling of metallic shapes, and cracks were observed on the surfaces of all cases except for Comparative Example 1. There wasn't. However, in Comparative Example 1, the aluminum cloth on the surface corroded.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of an antenna to which a typical reflector for a circularly polarized antenna manufactured according to the present invention is attached. Moreover, FIG. 2 is a sectional view of the reflector for the circularly polarized antenna. Furthermore, FIG. 3 is a partially enlarged view of the cross-sectional view. A...Reflector for circularly polarized antenna, B...Converter, C...Converter support rod, D...Reflector support rod, E...Wiring, ■...Thermoplastic resin layer, A laminate consisting of one layer of primer, a metallic shaped object, and one layer of primer, 1.. Inorganic filler-containing vinyl chloride polymer layer, 2. Inorganic filler-containing vinyl chloride polymer layer. 2...Metallic shaped object, 3...Thermoplastic resin layer with excellent weather resistance, 2a...
Primer 1st layer, 2b...Primer 1st layer Fig. 3

Claims (1)

[Claims] At least (A) a thermoplastic resin layer with good weatherability (B)
) A laminate formed by sequentially laminating at least one shaped object selected from the group consisting of metallic mats, cloths and nets and (C) a vinyl chloride polymer layer containing an inorganic filler, the thermoplastic resin The thickness of the layer is 5 microns to 5 mm, the metallic mat, cloth and net is finer than 2 meshes, and the thickness of the vinyl chloride polymer layer containing inorganic filler is 500 microns to 15 nm+m, A reflector for a circularly polarized antenna, characterized in that the content of the inorganic filler in this layer is 10 to 80% by weight.