JPS62101654A - Metallic fiber-containing resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which is lightweight and has excellent electrical conductivity and electromagnetic wave shielding properties, by blending a thermoplastic resin with specified stainless steel fiber and metallic fiber. CONSTITUTION:A thermoplastic resin (A) (e.g., PS) is mixed with 0.1-2vol% stainless steel fiber (B) having a diameter of 2-15mum, pref. 4-10mum, and an aspect ratio of 200 or above, pref. 400-900, and 0.1-10vol% metallic fiber (C) having a diameter of 10-150, pref. 20-100mum, and an aspect ratio of 10-100, pref. 30-50 (e.g., Al), in such a proportion that the quantity of a mixture of the components B and C accounts for 0.2-12vol% of the compsn. Optionally, an antistatic agent, a colorant (e.g., cadmium yellow), a flame retarder (e.g., Sb2O3), an antioxidant (e.g., salicylate), an inorg. filler (e.g., talc), etc., are added thereto.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a metal fiber-containing resin composition, and more specifically, a resin composition containing metal fibers suitable for electromagnetic shielding materials or electrical protection materials. The present invention relates to a resin composition.

[Prior Art and its Problems] In recent years, in the field of housings for electronic devices, office automation equipment, home appliances, and the like, synthetic resins have been increasingly used in products. However, since the synthetic resin 1 transmits electromagnetic waves emitted from electronic devices and the like, electromagnetic interference such as generation of noise and malfunction of elements etc. occurs.

As a method to prevent this electromagnetic interference, it is known that a resin composition with conductivity is formed by blending a metal edge, W3, into the resin material, and a housing is made from this conductive resin composition. It is being Concretely, hour IV
(Publication No. 58-14457 discloses a resin composition formed by blending metal fibers and metal powder with a thermoplastic resin,
Furthermore, Japanese Patent Application Laid-open No. 59-189142 discloses a resin composition comprising a thermoplastic resin mixed with metal fibers and carbon fibers.

However, since such resin compositions contain only a small amount of metal fibers, they do not have sufficient conductive effect. Although it is possible to improve conductivity, the mechanical strength such as impact resistance of the molded product decreases.Also, the inclusion of large amounts of metal fibers deteriorates the moldability of the resin composition and causes problems with molds and molds. This may cause wear and damage to molding machines, etc.

[Purpose of the invention] This invention has been made based on the above circumstances.

That is, the object of the present invention is to provide a synthetic resin that has excellent electrical conductivity without deteriorating the mechanical properties inherent in synthetic resins, and is suitable for electromagnetic shielding materials or antistatic materials.
A resin containing metal fibers that does not cause wear or damage to molding machines, etc.! Our goal is to provide you with a wealth of money.

[Means for achieving the above object] In order to achieve the above object, the inventor has made various studies and surprisingly found that when a thermoplastic resin is blended with a small amount of a specific metal fiber. The present invention was achieved by discovering that a resin m-acid having excellent conductivity can be obtained without causing a decrease in mechanical strength.

The gist of this invention for achieving +nJn diary is that thermoplastic resin, stainless steel fiber with a diameter of 2 to 15 Bm and an aspect ratio of 200 or more, and a thermoplastic resin with a diameter of 10
~150 μm and an aspect ratio of lO~10
0 metal fibers, and the total of the thermoplastic resin, the stainless steel fibers, and the metal fibers is 100
When expressed as volume %, the blending amount of the stainless steel fiber is 0.
．． 1 to 2% by volume, and the blending amount of the metal fiber is 0.1
This is a metal fiber-containing resin composition characterized in that the metal fiber content is 10% by volume.

Examples of the thermo-OT plastic resin include general resins such as polyolefin resins, vinyl chloride resins and copolymer resins thereof, vinylidene chloride resins, polystyrene and copolymer resins thereof, polyamide resins, polyacetals, polycarbonates, and 8-plastic polyester resins. , engineering plastics such as polyphenylene oxide, noryl resin, and polysulfone.

Examples of the polyolefin resin include polyethylene such as high-density polyethylene, medium- and low-density polyethylene, and linear low-density polyethylene; polypropylene such as isotactic polypropylene, syndiotactic polypropylene, and atactic polypropylene; polybutene; -Methylpentene-1 resin etc., and
In this invention, ethylene-propylene copolymer,
Copolymers with olefins such as ethylene-vinyl acetate J (polymers, ethylene-vinyl chloride copolymers, propylene-vinyl chloride copolymers) can also be used.

Examples of the vinyl chloride copolymer resin include vinyl chloride-vinyl acetate resin, vinyl chloride-vinylidene chloride copolymer resin, and vinyl chloride-acrylonitrile copolymer resin.

As the polystyrene copolymer resin, for example, A
Examples include BS resin and SAN resin.

Examples of polyamide resins include nylon 6, nylon 8, nylon 11, nylon 66, and nylon 610.
Examples include.

The polyacetal may be a single polymer (Delrin) or a copolymer (Duracon).

As the polycarbonate, for example, a polycarbonate obtained from bisphenol A, phosgene, and force 1,
Examples include polycarbonate obtained from bisphenol A and diphenyl carbonate.

Examples of the thermoplastic polyester resin include polyethylene terephthalate and polypropylene terephthalate.

Since the metal fiber-containing resin composition according to the present invention is to be subjected to molding, the various thermoplastic resins may be selected as appropriate, as long as the thermoplastic resin has a molecular weight suitable for molding. can be used. The above various thermoplastic resins may be used alone, or two or more types may be mixed and used as a polymer blend. However,
Among the various thermoplastic resins mentioned above, polystyrene and copolymer resins thereof are preferred. More preferably, polybutadiene, ABS resin, SBS resin 1MB
5 resin, rubber such as NAS resin to styrene monomer 2
Polystyrene (so-called high-impact polystyrene) obtained by dissolving or mixing ~20% by weight and polymerizing the styrene monomer and dispersing soft component particles, AB
It is S resin.

There are no particular restrictions on the stainless steel that is the material for the stainless steel fibers, and for example, chromium-based stainless steel, nickel-chromium-based stainless steel, etc. can be used.

It is important that the stainless steel fiber has a diameter of 2 to 15 Im, preferably 4 to 10 Bm, and an aspect ratio of 200 or more, preferably 400 to 900.

If the diameter of the stainless steel is smaller than 2 μm, the stainless fiber will break when kneading the stainless steel fiber and the thermoplastic resin, and the conductivity imparting effect will disappear; descend.

Moreover, when the aspect ratio is smaller than 200, the electrical conductivity of the resin composition decreases.

Examples of the metal fibers include fibers of metals such as brass, aluminum, copper, Nylarkel, stainless steel, silicon steel, tfff copper, phosphor bronze, Fernico, and permalloy. Note that as a substitute for the metal fibers, glass fibers whose surfaces are plated or coated with metal can be used.

The metal fiber has a diameter of 10 to 150 pm, preferably 20 to 1100 pm, and an aspect ratio of 10 to 1.
00. It is important that the number is preferably 30 to 70.

If the diameter of the metal fiber is smaller than 10 μm, the reinforcing effect will be reduced, and if the diameter is larger than 150 μm, the impact resistance of the molded article of the metal fiber-containing resin composition will be reduced.

When the aspect ratio of the metal m-fibers is smaller than 10, the reinforcing effect is reduced, and when the aspect ratio is larger than lOO, the impact resistance of the molded article of the metal fiber-containing resin composition is reduced.

The stainless steel fibers and metal fibers can be manufactured by, for example, a melt spinning method, a stretching method, a wire drawing method, an extrusion method, a cutting method, or the like.

The stainless steel fibers are preferably degreased or pickled and treated on the convergence side before being blended with the thermoplastic resin.

Examples of degreasing include solvent degreasing, immersion degreasing, alkaline degreasing, and surfactant degreasing.

There are no particular restrictions on the convergence agent used for the convergence side treatment as long as it is soluble in the solvent, such as polyester resin, ABS, etc.
There are thermoplastic resins such as resin, polystyrene resin, and polyolefin resin. Moreover, a tackifier such as a terpene resin can also be used in combination, if necessary.

As a preferred pretreatment method, after degreasing, the bundle of stainless steel fibers is immersed in a solution of a thermoplastic resin and a tackifier in a hydrocarbon solvent, and then, after drying, the stainless steel fibers are cut into a predetermined length. An example of this is cutting at the right angle.

On the other hand, the metal fibers are preferably degreased or pickled as a pretreatment.

In the metal fiber-containing resin composition according to the present invention, the heat I
JT plastic resin, stainless steel fibers having the above specific dimensions, and metal m having the above specific dimensions.
It should be noted that the fibers are blended in a specific ratio of -1.

That is, this metal fiber-containing resin composition has a total of 11 thermoplastic resins, stainless steel fibers, and metal W&M.
The amount of stainless steel fibers having the specific dimensions is 0.1 to 2% by volume, preferably 0.3 to 1.0% by volume, and the specific dimensions are 1% to 1% by volume. The proportion of metal fibers with 0.1-10% by volume, preferably 1-8% by volume.

If the blending amount of the stainless steel m1lI is less than 0.1% by volume, sufficient conductivity cannot be imparted to the metal fiber-containing resin composition even though it is a metal fiber-containing resin composition. If the blending amount exceeds 2% by volume, the dispersion of stainless steel lI&m in the resin will be poor, and the moldability will deteriorate, and even if a molded product is obtained, the molded product will have poor resistance to #i impact. Sexuality drops a lot.

If the amount of the metal wt fibers is less than 0.1% by volume, even though it is called a metal fiber-containing resin composition, it will not be possible to impart upward conductivity to the metal fiber-containing resin composition, and the When the blending amount is more than 1O volume%,
The dispersion of the metal fibers in the resin becomes uneven, and the moldability deteriorates, and even if a molded product is obtained, the impact resistance of the molded product decreases significantly and the specific gravity increases. .

Furthermore, regarding the amount of the stainless steel fibers and the metal fibers, it is desirable that the total amount of the stainless steel fibers and the metal fibers be 0.2 to 12% by volume, preferably 1 to 10% by volume.

If the total blending amount is less than 0.2% by volume, this metal m
It is not possible to impart sufficient electrical conductivity to the fiber-containing resin composition, and if the amount is more than 12% by volume, the metal fibers will not be sufficiently dispersed in the resin, and the moldability will deteriorate. At the same time, even if a molded article is obtained, the impact resistance of the molded article is reduced.

This metal fiber-containing resin composition may be added with an antistatic agent, a coloring agent, a flame retardant, an antioxidant, an ultraviolet absorber, a town/W agent, an inorganic filler, as necessary, as long as it does not impede the cutting effect of this invention. Various additives such as additives and heat stabilizers can be added and blended.

Various surfactants can be used as the antistatic agent. Examples of the coloring agent include poorly soluble undyed dye 1, red coloring agent, cadmium yellow, cream yellow, titanium white, and the like. Examples of the flame retardant include inorganic antimony oxide and zirconium oxide, and organic phosphoric acid esters and tricresyl phosphate. As the antioxidant,
Triazole-based, salicylic acid-based, and acrylonitrile-based materials are used. Furthermore, examples of the plasticizer include phthalic acid diester, butanol diester, phosphoric acid diester, and the like. Examples of the inorganic filler include) calcium pentate, and gypsum.

Examples include talc, mica, barium sulfate, glass beads, wollastonite, magnesium hydroxide, and aluminum hydroxide.

Examples of the inorganic filler include acid 111 (such as calcium carbonate, magnesium carbonate, and dolomite).
, sulfates such as calcium sulfate and magnesium sulfate, sulfites such as calcium sulfite, talc, clay, mica,
Asbestos, glass! I, silicates such as glass peas, calcium silicate, montmorillonite, bentonite, ceramics such as silicon carbide, silicon nitride, their whiskers, carbon black, graphite, carbon fibers, etc., and these inorganic fillers The above-mentioned inorganic fillers can be used alone or in combination of two or more kinds.

Among the various inorganic fillers, carbonates, sulfates, and silicates are preferred, and calcium carbonate, barium sulfate, talc, mica, and zinc powder are particularly preferred. The carbonic acid and barium sulfate improve the surface smoothness and gloss of the plastic molded product, and can also improve the liIM property and abrasion resistance of the plastic molded product.

The metal fiber-containing resin composition according to Issue 11 includes the thermoplastic resin, the stainless steel fibers having specific dimensions,
It can be manufactured by blending the metal fibers having specific dimensions, and further blending the various additives as necessary.

There are no particular restrictions on the blending method; for example, tri-blending may be performed using a mixer such as a Henschel mixer, or melt-kneading may be performed using a Banbury mixer, roll mill, screw extruder, etc. The various additives mentioned above may be added at the time of this crosstalk.

The metal fiber-containing resin composition thus obtained is molded into various molded products by various molding methods such as injection molding, cast molding, extrusion molding, and press molding.

The metal fiber-containing resin composition obtained in this way has improved conductivity without reducing the mechanical strength of the molded product, so it is suitable for the industrial material field as an electromagnetic shielding material and an antistatic material. Can be used and useful.

[Effects of the Invention] According to the present invention, since the thermoplastic resin, the stainless steel fibers having specific dimensions, and the metal fibers having specific dimensions are blended in a specific ratio, this metal fiber-containing resin composition It is possible to improve conductivity and electromagnetic shielding properties without reducing the mechanical strength of various molded products. Furthermore, since only a small amount of metal fiber is blended, this metal fiber-containing resin composition is lightweight.

Therefore, this metal fiber-containing resin composition is very useful as a material for preventing charging or shielding electromagnetic waves emitted from electronic devices and various elements.

[Examples] Next, the present invention will be explained in more detail by showing examples and comparative examples of the present invention.

(Examples 1 to 5. Comparative Examples 1 to 8) Thermoplastic resins of the types shown in the footnotes of Table 1, stainless steel fibers, metal fibers, etc. are triblended at the blending ratios shown in Table 1, injection molded, and tested. The pieces were shaped. Izot impact strength for this test piece.

The volume resistivity and EMI shielding properties were evaluated.

In addition, the Izotsu impact strength is based on ASTM 0256 (with switch), the measurement of the 1 volume resistivity value is based on the Japan Rubber Association standard SPI 32301, and the EM shielding property is based on the Takeda Riken method! This is an evaluation of the electromagnetic shielding properties of i00MH2.

The results are shown in Table 1.

Claims (4)

[Claims] (1) A thermoplastic resin and a stainless steel fiber having a diameter of 2 to 15 μm and an aspect ratio of 200 or more,
The diameter is 10 to 150 μm and the aspect ratio is 1.
0 to 100% by volume, and when the total of the thermoplastic resin, the stainless steel fibers, and the metal fibers is 100% by volume, the blending amount of the stainless steel fibers is 0.1 to 2% by volume. A metal fiber-containing resin composition characterized in that the amount of the metal fibers is 0.1 to 10% by volume. (2) The total of the stainless steel fiber and the metal fiber is 0.
．． The metal fiber-containing resin composition according to claim 1, which has a content of 2 to 12% by volume. (3) The metal fiber-containing resin composition according to claim 1 or 2, wherein the thermoplastic resin is polystyrene and/or ABS resin. (4) The metal fiber-containing resin composition according to any one of claims 1 to 3, wherein the metal fibers are aluminum and/or brass.