JPH10195311A - Thermoplastic resin molding, material for molding and production of molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molding having high strengths and being desirable for static electricity dissipation materials and magnetic shielding materials by selecting a molding containing glass fibers made of resin pellets prepared by fully impregnating glass fiber bundles with a resin and having a specified or longer fiber length (as measured on the fibers remaining in the molding) and a conductive material in a specific mixing ratio. SOLUTION: This invention provides a thermoplastic resin molding containing glass fibers and a conductive material, wherein glass fibers having a length of 0.4mm or longer amount to 5-60wt.% of the total glass fibers, the total weight of the glass fibers is 5-75wt.%, and the amount of the conductive material used is 3-60wt.%. The conductive material is exemplified by carbon black, carbon fibers or stainless steel fibers. The thermoplastic resin desirably used is a resin of a polyolefin, polyamide or ABS type. An economically desirable example of a method for obtaining such a molding consists of injection-molding pellets made of glass fiber bundles fully impregnated with a thermoplastic resin and containing a conductive material under low pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long glass fiber reinforced conductive resin molded article having conductivity and excellent in both heat resistance and mechanical properties, and a glass length used for manufacturing the molded article. The present invention relates to a material for a fiber-reinforced conductive resin molded product and a method for producing a glass long fiber-reinforced conductive resin molded product.

[0002] The long glass fiber reinforced conductive resin molded article of the present invention is particularly preferably used as a static electricity dissipating material or an electromagnetic wave shielding material.

[0003]

2. Description of the Related Art A thermoplastic resin is imparted with conductivity by being combined with a conductive material, and is widely used in applications such as static electricity dissipation and electromagnetic wave shielding. Thermoplastic resins containing conductive materials can be molded into various shapes by injection molding, injection compression molding, etc., and can be mass-produced at low molding costs, so they can be used for static electricity dissipation and electromagnetic wave shielding. It is inexpensive and has high industrial value as compared with metal processed products used in the field, or surface conductive processed products such as conductive coating materials and metal plated products.

[0004] On the other hand, however, a molded article using a thermoplastic resin containing a conductive material has insufficient mechanical strength, leaving room for study. For this reason, conventionally, studies have been made to improve the strength by adding a fibrous reinforcing material such as glass fiber. In order to improve the strength, the effect of the fiber length in the molded product is remarkable. Even if a long fiber of, for example, 1 mm or more is used as the material for the molded product, the fiber is broken during the molding process, and most of the fibers are broken. The long fiber becomes less than 0.2 mm,
No significant reinforcing effect was seen.

[0005] A specific example will be described below based on the prior art. JP-A-63-90564 proposes a resin composition comprising a thermoplastic resin, stainless steel fiber and glass fiber. In the above technology, the fiber diameter is 5-50
μm, glass fibers having an aspect ratio of 50 to 500 are used, and when converted, the glass fiber length of the glass fibers is 0.25.
Equivalent to ~ 25mm.

However, even when glass fibers having such a fiber length are used, the above composition is melt-kneaded by an extruder,
If pellets for injection molding are obtained, the glass fibers will break during the melt-kneading step, resulting in a shorter glass fiber. JP-A-59-2359
No. 5, JP-B-62-36069, JP-A-60-88064
JP, JP-B4-68348, JP-A-63-132959, and JP-B-5-55961 also disclose conductive resin compositions to which glass fibers are added. Melted and kneaded by a twin or single screw extruder,
It is pelletized and the glass fiber is shortened.

As described above, in the prior art, the conductive material, the thermoplastic resin, and the glass fiber are melt-kneaded by an extruder and pelletized in consideration of uniform dispersibility in a resin molded product. The fibers were shortened and the mechanical strength was insufficient. In JP-A-63-90564, a glass fiber bundle converged with a sizing agent is pelletized,
A method for directly performing injection molding is disclosed.

JP-A-60-18315 discloses a pellet-shaped conductive molding material in which a resin layer is formed on the surface of a bundle of a fibrous conductive material and inorganic fibers (glass fibers). However, molding material in which only the surface of the glass fiber bundle is coated with a sizing agent or a thermoplastic resin,
Since the resin is not impregnated in the glass fiber bundle, when the glass fiber bundle is injection molded, the glass fiber is shortened due to friction between the glass fibers or shearing by the unmelted resin, screw or the like at the time of melt-kneading.

As described above, in the prior art, the glass fiber added for improving the strength is shortened at the time of molding, and the strength of the obtained molded product is insufficient.

[0010]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and has excellent mechanical strength and electrical conductivity, and a molded article suitable for obtaining the molded article. It is an object of the present invention to provide an article material and a method for producing the molded article.

[0011]

The inventor of the present invention has stated that by increasing the length of glass fibers in a molded article, it is possible to achieve high strength of a thermoplastic resin molded article containing glass fibers and a conductive material. I thought and studied diligently. In order to suppress breakage of the glass fiber during the forming process as much as possible and to increase the length of the glass fiber in the formed product, it is possible to consider a forming apparatus and forming conditions.

[0012] For example, in the case of the injection molding method, there is a device of a molding apparatus in which the design of a screw is changed to a deep groove type and a compression ratio is lowered. Examples of the molding processing conditions for keeping the glass fiber length long include a method of lowering the screw rotation speed to lower the shearing force, a method of lowering the back pressure, and the like. When such a method is combined, the fiber length tends to be maintained longer, but on the other hand, the uniform dispersibility of the glass fiber and the conductive material decreases, and the strength and conductivity of the molded product become non-uniform.

For this reason, the present inventor paid attention to the resin impregnation of the material, particularly the glass fiber-containing pellet. As described above, in the prior art, a glass fiber bundle coated with a sizing agent or a thermoplastic resin is used. However, in the above-mentioned pellets, the resin is not basically impregnated in the glass fiber bundle, and the glass is rubbed with each other at the time of processing and molding, and the pellets are shortened.

The inventor of the present invention has proposed that a glass fiber bundle has a long fiber length by using a resin pellet containing glass fiber sufficiently impregnated with a resin in the glass fiber bundle, that is, the glass fiber is sufficiently wetted with the resin. In this state, it was found that a thermoplastic resin molded article containing a conductive material and remaining in the molded article can achieve high strength. this is,
By impregnating the resin in the glass fiber bundle, it is possible to reduce the friction between the glasses during melt-kneading, and when a shear force is applied, the resin existing between the glass fibers is displaced and absorbs the shear energy. ,
It is considered that breakage of the glass fiber is suppressed.

Further, when the molded article obtained from the resin pellets according to the present invention described above was intensively analyzed, among the glass fibers in the molded article, fibers having a residual fiber length of 0.4 mm or more greatly contributed to the strength. It was found that a molded product having excellent strength characteristics was obtained by allowing 5 to 60% by weight of a glass fiber of 0.4 mm or more to be present in the molded product.

That is, the present invention is as follows.
A first invention is a thermoplastic resin molded article containing glass fiber, a conductive material, and a thermoplastic resin. The molded article contains 5 to 60% by weight of glass fiber having a length of 0.4 mm or more, It is a thermoplastic resin molded article having electroconductivity reinforced with long glass fibers, comprising 5 to 75% by weight in total of fibers and 3 to 60% by weight of conductive material.

In the first aspect, the conductive material is preferably at least one selected from carbon black, carbon fiber, stainless steel fiber, copper fiber, and brass fiber. In the first aspect, it is preferable that the thermoplastic resin is at least one selected from a polyolefin-based resin, a polyamide-based resin, a polystyrene-based resin, and an ABS-based resin.

Further, in the above-mentioned first invention,
Preferably, the glass fibers have been treated with a coupling agent. A second invention is a material for a thermoplastic resin molded article including a thermoplastic resin pellet containing a glass fiber bundle and a conductive material, wherein the weight average fiber length of the glass fiber in the thermoplastic resin pellet is 1 mm or more. And the glass fiber bundle in the thermoplastic resin pellets is impregnated with a thermoplastic resin, and the content of all glass fibers in the material for the thermoplastic resin molded product is 5 to 75% by weight, and the content of the conductive material. Is 3 to 60% by weight, and is a material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers.

A third invention is a thermoplastic resin pellet containing a glass fiber bundle and a conductive material, and a material for a thermoplastic resin molded article containing a thermoplastic resin, wherein the glass fiber in the thermoplastic resin pellet is provided. Weight average fiber length of 1mm
Above, and the glass fiber bundle in the thermoplastic resin pellets is impregnated with a thermoplastic resin, the content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight, and the conductive material is contained. An amount of 3 to 60% by weight is a material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers.

A fourth invention is a thermoplastic resin pellet containing a glass fiber bundle and a material for a thermoplastic resin molded article containing a conductive material, wherein the weight average fiber of the glass fiber in the thermoplastic resin pellet is A glass fiber bundle having a length of 1 mm or more and being impregnated with a thermoplastic resin in the thermoplastic resin pellets, wherein the content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight; Material content is 3
It is a material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers, characterized in that the content is about 60% by weight.

According to a fifth aspect of the present invention, there is provided a material for a thermoplastic resin molded article including a thermoplastic resin pellet containing a glass fiber bundle, a conductive material, and a thermoplastic resin. Glass fiber weight average fiber length is 1mm
Above, and the glass fiber bundle in the thermoplastic resin pellets is impregnated with a thermoplastic resin, the content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight, and the conductive material is contained. An amount of 3 to 60% by weight is a material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers.

In the second to fifth inventions, the thermoplastic resin pellets have an average length of 1 to 150 mm.
Preferably, the glass fibers in the pellet are aligned in the length direction of the pellet, and the glass fiber has substantially the same length as the pellet. A sixth invention is a material for a thermoplastic resin molded article including glass fiber reinforced thermoplastic resin pellets containing a conductive material, wherein the glass fiber reinforced thermoplastic resin pellets contain a thermoplastic resin in a glass fiber bundle. Impregnated, the pellet obtained by cutting, and the glass fiber has substantially the same length as the pellet,
The fibers are aligned in parallel with each other, and the glass fiber content is 10 to
90% by weight, a pellet having an average length in the fiber direction of 1 to 150 mm, which is a material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers.

A seventh invention is a glass fiber reinforced thermoplastic resin pellet containing a conductive material, and a material for a thermoplastic resin molded article containing a thermoplastic resin, wherein the glass fiber reinforced thermoplastic resin pellet comprises: A glass fiber bundle is impregnated with a thermoplastic resin and pellets obtained by cutting, and the glass fibers have substantially the same length as the pellets, the fibers are aligned in parallel, and the glass fiber content is reduced. This is a material for a thermoplastic resin molded article having conductivity reinforced by long glass fibers, which is a pellet having a weight of 10 to 90% by weight and an average length in a fiber direction of 1 to 150 mm.

An eighth invention is a material for a thermoplastic resin molded article containing a glass fiber reinforced thermoplastic resin pellet and a conductive material, wherein the glass fiber reinforced thermoplastic resin pellet is formed of a thermoplastic resin in a glass fiber bundle. Impregnated with resin, pellets obtained by cutting, and the glass fibers have substantially the same length as the pellets, the fibers are aligned in parallel,
A material for thermoplastic resin moldings having a glass fiber content of 10 to 90% by weight and an average length in the fiber direction of 1 to 150 mm and having conductivity reinforced with long glass fibers. is there.

A ninth invention is a material for a thermoplastic resin molded article including a glass fiber reinforced thermoplastic resin pellet and a thermoplastic resin pellet containing a conductive material, wherein the glass fiber reinforced thermoplastic resin pellet is In a pellet obtained by impregnating a glass fiber bundle with a thermoplastic resin and cutting,
And, the glass fibers have substantially the same length as the pellet, the fibers are aligned in parallel, the glass fiber content is
A thermoplastic resin molding material characterized in that the pellet is 10 to 90% by weight and has an average length in the fiber direction of 1 to 150 mm.

According to a tenth aspect, there is provided a thermoplastic resin molded material containing a glass fiber reinforced thermoplastic resin pellet, a conductive material, and a thermoplastic resin, wherein the glass fiber reinforced thermoplastic resin pellet is made of glass. The fiber bundle is impregnated with a thermoplastic resin and pellets obtained by cutting, and the glass fibers have substantially the same length as the pellets, the fibers are aligned in parallel, and the glass fiber content is 10%. A material for a thermoplastic resin molded article having conductivity reinforced with long glass fibers, which is a pellet having a length of 1 to 150 mm in a fiber direction of 90% by weight.

In the second to tenth aspects, the conductive material may be carbon black, carbon fiber,
It is preferably at least one selected from stainless steel fiber, copper fiber and brass fiber. In addition, the second
In the invention to the tenth invention, the thermoplastic resin,
It is preferably at least one selected from a polyolefin resin, a polyamide resin, a polystyrene resin and an ABS resin.

In the second to tenth aspects, the glass fiber bundle is preferably a glass fiber bundle treated with a coupling agent. An eleventh invention is characterized in that the material for a thermoplastic resin molded article having conductivity reinforced by a long glass fiber of at least one of the second invention to the tenth invention is molded. This is a method for producing a thermoplastic resin molded article having conductivity reinforced by long glass fibers.

In the eleventh aspect, it is preferable to use an injection molding method as a method for molding the material for a thermoplastic resin molded article.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The present inventor has conducted intensive studies to solve the above-described problems of the related art, and at least, glass fiber reinforced thermoplastic resin pellets impregnated with a thermoplastic resin in a glass fiber bundle, and conductive carbon black, By using a material for a molded article containing a conductive material such as a conductive fiber and molding so that the content of glass fiber of 0.4 mm or more in the molded article falls within a specific range, it has conductivity, and It has been found that a fiber-reinforced thermoplastic resin molded article having excellent mechanical properties such as heat resistance, impact resistance, tensile strength, tensile modulus, flexural strength and flexural modulus can be obtained.

The thermoplastic resin molded article having conductivity reinforced by long glass fibers of the present invention comprises, in the final thermoplastic resin molded article, a long glass fiber having a fiber length of 0.4 mm or more, and a conductive material. Any production method and molding method may be used as long as it is contained in a specific amount. However, from the viewpoint of uniformity of the characteristics of the molded article and economical efficiency, it is preferable to produce the molded article by the following method.

That is, a thermoplastic resin pellet impregnated in a glass fiber bundle and containing a conductive material is molded as a material for a molded article by an injection molding method such as low pressure injection molding or injection compression molding. It is preferable to obtain a molded product. Also, a thermoplastic resin pellet in which a thermoplastic resin is impregnated in a glass fiber bundle, and a thermoplastic resin pellet containing a conductive material are respectively manufactured, and a material for a molded product in which both pellets are mixed is subjected to low pressure injection molding. It is preferable to obtain a molded product by molding by an injection molding method such as injection compression molding.

The materials for molded articles, molded articles, their raw materials and production methods of the present invention will be described below. (Glass fiber :) The type of glass fiber used in the present invention is:
Commonly used glass fibers may be used. For example, E-glass, AR-glass, T-glass, D-glass, S-glass, C-glass, R-glass and the like are exemplified.

The form of the glass fiber used in the present invention is preferably a continuous glass fiber bundle usable in a drawing method. For example, a bundle of thousands to tens of thousands of glass filaments is wound into a coil. , So-called glass roving. A glass fiber having a diameter of 5 to 35 μm is suitable. When the diameter of the glass fiber is less than 5 μm,
When the same glass content is used, the number of glass fibers relatively increases, so that it becomes difficult to impregnate the glass fiber bundle with the resin. Conversely, when the glass fiber size exceeds 35 μm, the surface appearance of the molded product is significantly deteriorated.

The optimal glass fiber diameter is 9 to 20 μm. When the cross-sectional shape of the glass fiber is not circular,
The area equivalent diameter, which is the diameter of a circle having an area equal to the cross-sectional area, is preferably 5 to 35 μm, and more preferably the area equivalent diameter is 9 to 35 μm.
Preferably, 20 μm glass fibers are used. The glass fiber used in the present invention is preferably surface-treated with a surface treatment agent containing a coupling agent.

When the surface treatment of the glass fiber with the coupling agent is performed, the impregnation of the resin into the glass fiber bundle is improved, the adhesion between the glass fiber and the resin is improved, and the strength of the molded product is improved. As coupling agents, aminosilane, epoxysilane, amidosilane, azidosilane,
A silane coupling agent such as acrylic silane, a titanate coupling agent, or a mixture thereof can be used.

Of these, aminosilane and epoxysilane are preferred, and aminosilane coupling agents are particularly preferred. The surface treatment agent may contain a surfactant, an antistatic agent and the like in addition to the coupling agent. (Conductive Material :) As the conductive material, preferably, carbon black, carbon fiber, stainless steel fiber, brass fiber, copper fiber and the like are exemplified.

These may be used alone or in combination of two or more. Examples of carbon black include furnace black and acetylene black. Furnace black, conductive carbon black such as acetylene black, use the 10 ^{0 -} 10 ² have Ωcm about high volume resistivity, the molded article of the present invention using them as the conductive material of the IC chip trays applications If it does, it will show excellent performance in terms of static electricity dissipation.

Furnace black is produced by burning crude oil by a furnace-type incomplete combustion method. For example, Vulcan XC-72, Ketjen Black EC (both trade names) and the like can be used. In the present invention, the carbon black is contained in the material for a molded article of the present invention, preferably in an amount of 3 to 60% by weight, preferably 5 to 40% by weight, more preferably 5 to 25% by weight. A molded article having conductivity can be obtained.

The carbon fibers are roughly classified into two types, that is, PAN type and pitch type. Both types are excellent in conductivity and 10 ^-4 to 10 ^-3 Ω.
Has a volume resistivity of cm. In the present invention, any carbon fiber can be used, and graphitized carbon fiber is also preferably used. Further, carbon fibers plated with a metal such as nickel can also be used, and can be obtained by plating the above PAN-based or pitch-based carbon fibers.

Since nickel-plated carbon fiber has a small volume resistivity, it is useful as an application for electromagnetic wave shielding. Stainless fibers, brass fibers, and copper fibers are produced by a drawing method or a chattering method. Carbon fiber, stainless steel fiber, copper fiber, brass fiber, resin composite material containing conductive fiber such as carbon fiber plated with metal such as nickel,
Since very high conductivity can be imparted by adding a small amount of these conductive materials, it is an indispensable conductive material for a low electric resistance resin composite material as an electromagnetic wave shielding material.

The above-mentioned fibrous conductive material is preferably used in the form of pellets previously compounded with a resin in order to achieve uniform dispersion in a molded article. The content of the conductive fiber such as carbon fiber, stainless fiber, copper fiber, brass fiber, carbon fiber plated with metal such as nickel is 3 to 60% by weight, preferably 3 to 60% by weight in the molded article material and molded article of the present invention. More preferably, it is 3 to 50% by weight, more preferably 3 to 30% by weight.

In order to obtain electromagnetic wave shielding properties (EMI shielding properties), the content of the above-mentioned molded product should be 7% by weight or more in the case of stainless steel fiber and 10% by weight or more in the case of carbon fiber. Is more preferred. Further, in the case of the metal fiber obtained by the chattering method, in order to obtain the EMI shielding property, the content of the above-mentioned molded article is set at 15%.
It is more preferable that the content be not less than% by weight.

(Thermoplastic resin) The kind of the thermoplastic resin used in the present invention is not particularly limited. However, when a crystalline resin such as a polyolefin-based resin or a polyamide resin such as syndiotactic polystyrene, 6-nylon, 6,6-nylon is used, it is represented by a weighted deflection temperature (HDT) due to the compounding with a long fiber. This is advantageous because the thermal characteristics are improved.

In particular, polyolefin-based resins are particularly preferable because they are inexpensive and are industrially and economically excellent from the viewpoint of recycling and the like. Hereinafter, the polyolefin resin will be described in detail. As the polyolefin resin used in the present invention, ethylene, propylene, butene,
Homopolymers such as 4-methylpentene are exemplified, and also random, alternating, block, or graft copolymers of these monomers with polar monomers such as vinyl acetate, acrylic acid, acrylates, and maleic anhydride. included.

Further, a composition in which a synthetic rubber such as ethylene-α-olefin copolymer rubber, isoprene rubber, isobutylene rubber or the like is added to the polymer in an amount of less than 50% by weight is also included. Specifically, high-pressure ethylene homopolymer, high-pressure ethylene-propylene copolymer, low-pressure ethylene homopolymer, low-pressure ethylene-propylene copolymer, low-pressure ethylene-1-butene copolymer, low-pressure ethylene Ethylene-1
-Hexene copolymer, medium pressure method ethylene copolymer, high pressure method ethylene-vinyl acetate copolymer, propylene-ethylene random or block copolymer, and the like.

Further, among the above-mentioned polyolefin-based resins, a crystalline propylene-based polymer, particularly, polypropylene is preferable. As the polypropylene, other than propylene homopolymer, a copolymer containing propylene as the main component and an ethylene component, such as a propylene-ethylene block copolymer, a block copolymer of propylene and ethylene-propylene rubber, and the like. Good.

In the present invention, as the thermoplastic resin, acrylonitrile-butadiene-styrene resin (ABS resin), polystyrene, polycarbonate, polysulfone (PSU), polyphenylene sulfide (PPS), polyether sulfone (PES) and the like are used. Even when an amorphous resin is used, mechanical strength such as impact strength, tensile strength, bending strength, and flexural modulus is improved by forming a composite with long glass fibers.

Particularly, since the Izod impact strength is greatly improved, it can be preferably used for applications requiring impact resistance, such as a housing or a housing of an electronic circuit. (Thermoplastic resin pellets containing glass fiber bundles, glass fiber reinforced thermoplastic resin pellets :) Thermoplastic resin pellets containing glass fiber bundles used in the present invention (second to fifth inventions) or glass fibers The reinforced thermoplastic resin pellets (the sixth to tenth inventions) can be manufactured by any method as long as the thermoplastic resin is impregnated in the glass fiber bundle and the weight average fiber length of the glass fiber is 1 mm or more. You may.

The glass fiber bundle is impregnated with a thermoplastic resin and then cut into a desired length to obtain a pellet according to the present invention. As a method of impregnating a thermoplastic resin into a glass fiber bundle, for example, a method of impregnating a glass fiber bundle with an emulsion of a thermoplastic resin, drying after coating is applied, a powder suspension of a thermoplastic resin into a glass fiber bundle. A method of heating and melting and impregnating after drying, charging the glass fiber bundle, and attaching the thermoplastic resin powder,
A method of heat-melting impregnation, a method of impregnating a glass fiber bundle with a thermoplastic resin dissolved in a solvent, and a method of removing the solvent, heating a mixed fiber of continuous fiber of thermoplastic resin and continuous fiber of glass, and melting the molten resin into glass. Any of a method of impregnating the fiber bundle and a method of impregnating the glass fiber bundle with the thermoplastic resin melted by heating on a bar, a roll, or a die may be used.

In the present invention, of these methods, a method of impregnating a heated and melted thermoplastic resin with a glass fiber bundle on a bar, a roll, or a die while opening the glass fiber bundle (drawing method) is used because of the simplicity of the apparatus and the process. Is preferred. In addition, at the time of resin impregnation, additives such as conductive materials, antioxidants, light stabilizers, and flame retardants, and reinforcing materials such as mica, talc, whisker titanate, wollastonite, glass flakes, and glass beads are added. You may.

The method of addition is not particularly limited. For example, a resin and the above-mentioned various additives are mixed and melted.
A method of impregnating the glass fiber bundle on a bar, roll, or die (drawing method) is exemplified. The glass fiber bundle impregnated with the resin is dried or cooled and cut into a desired length. The length of the pellet after cutting is preferably 1 to 150 mm in average length in the fiber direction, and more preferably 2 to 150 mm.
150150 mm, more preferably 2-100 mm, even more preferably 6-15 mm.

What is important here is that the weight average fiber length of the glass fibers in the pellets is 1 mm or more. When the weight-average fiber length of the glass fibers in the pellet is less than 1 mm, the amount of glass fibers having a length of 0.4 mm or more in the obtained molded article becomes small, and the mechanical strength becomes insufficient.

Therefore, the average length of the pellet in the fiber direction needs to be 1 mm or more. Conversely, if the average length of the pellets exceeds 150 mm, clogging tends to occur in the hopper of the molding machine. In addition, the average length of the above-mentioned pellet in the present invention is defined by the weight average length of the pellet.

Further, as the above-mentioned glass long fiber reinforced thermoplastic resin pellets, in the fiber reinforced thermoplastic resin pellets, the glass fibers are substantially the same length as the pellets and the fibers are aligned in the length direction of the pellets. Is preferred. In the present invention, the glass fiber content is 10 to
It is preferable to use 90% by weight, more preferably 30 to 70% by weight of long glass fiber reinforced thermoplastic resin pellets.

(Material for molded article) The material for a molded article of the present invention preferably has the following constitution. (1) A thermoplastic resin pellet reinforced with long glass fibers as described above, containing a conductive material. (2) A mixture of (a) a thermoplastic resin pellet reinforced with long glass fibers described above and a conductive material, and (b) a thermoplastic resin.

In this case, in order to uniformly mix the above (a) and (b), it is preferable to use a pellet as the above (b). (3) A mixture of (a) the thermoplastic resin pellet reinforced with the long glass fiber described above and (b) a conductive material. (4) A mixture of (a) the thermoplastic resin pellet reinforced with the long glass fiber, (b) a conductive material, and (c) a thermoplastic resin.

In the case of the above (4), in order to uniformly mix the conductive material, the conductive material and the thermoplastic resin are previously mixed using a kneader such as an extruder or a kneader.
It is preferable to use a thermoplastic resin pellet (d) containing a conductive material produced by molding as the above-mentioned (b) conductive material. The content of all the glass fibers in the above-mentioned (1) to (4) molding material is preferably 5 to 75% by weight in the molding material, more preferably 10 to 75% by weight in the molding material. 60% by weight.

When the content of the glass fiber is less than 5% by weight, the strength of the molded article is not sufficient. On the contrary, when it exceeds 75% by weight, molding becomes difficult and the appearance of the obtained molded article is also poor. become. The content of the conductive material in the material for a molded article of (1) to (4) is preferably 3 to 60% by weight in the material for a molded article, and more preferably 5 to 60% by weight in the material for a molded article. 50% by weight.

When the content of the conductive material is less than 3% by weight, the obtained molded product has insufficient conductivity and cannot be used for applications such as an electromagnetic wave shielding material. If it exceeds 60% by weight, molding becomes difficult. In the material for a molded article of the above (2), (a) a thermoplastic resin pellet reinforced with long glass fibers and containing a conductive material and (b) a thermoplastic resin preferably has a mixing ratio of (a) glass length. For 100 parts by weight of thermoplastic resin pellets reinforced with fibers and containing a conductive material, (b) thermoplastic resin 3 to
300 parts by weight.

Further, in the above-mentioned molded article material (3), the preferred compounding ratio of (a) the thermoplastic resin pellet reinforced with long glass fiber and (b) the conductive material is (a) long glass fiber. (B) 3 to 150 parts by weight of the conductive material based on 100 parts by weight of the reinforced thermoplastic resin pellets. Further, (a) a thermoplastic resin pellet reinforced with long glass fibers and (b) a conductive material in the molded article material of (4) above.
The preferred blending ratio of (c) thermoplastic resin is (a) 100 parts by weight of thermoplastic resin pellets reinforced with long glass fiber, (b) 3 to 150 parts by weight of conductive material, and (c) thermoplastic resin. Resin is 1 to 100 parts by weight.

Further, in the above (4), when the thermoplastic resin pellet (d) containing a conductive material is used, the preferable compounding ratio is (a) 100 wt% of the thermoplastic resin pellet reinforced with long glass fiber. (D) 5-300 parts by weight of thermoplastic resin pellets containing a conductive material. In the material for molded articles of the present invention, additives such as antioxidants, light stabilizers, and flame retardants described above, and mica, talc, whisker titanate, wollastonite, glass flakes, glass beads, etc. A reinforcing material may be included.

(Molding method) As a molding method in the present invention, any method for molding a resin, such as injection molding, blow molding, extrusion molding, etc., can be used. It is preferable to use a molding method, and an injection compression molding method and a low-pressure injection molding method are suitable because the glass fiber is hardly cut at the time of injection.

That is, the material for a molded article of the present invention is supplied to a molding machine and melt-kneaded in the molding machine. When molded using the material for molded articles of the present invention, it becomes easy to adjust the blending ratio of the glass fiber and the conductive material in the molded article to a desired range, the glass fibers are hardly broken, and the glass in the molded article is hardly broken. Fibers become longer and a molded article having high strength is obtained. Further, the dispersion of the glass fiber and the conductive material in the molded article becomes uniform, so that more excellent properties in strength and conductivity are obtained.

(Molded Article) The molded article of the present invention contains 3 to 60% by weight of a conductive material in the molded article. When the content of the conductive material is less than 3% by weight, the conductivity is insufficient and cannot be used for applications such as an electromagnetic wave shielding material. Conversely, when the content of the conductive material exceeds 60% by weight, The amount of the conductive material protruding from the surface of the molded product increases, resulting in poor appearance.

The content of all glass fibers in the molded article of the present invention is 5 to 75% by weight. When the content of all glass fibers is less than 5% by weight, there is little improvement in mechanical strength and heat resistance,
Excellent effects due to long glass fibers cannot be obtained. Conversely, 75
If the content is more than the percentage by weight, the fluidity at the time of melting is low, molding is difficult, and the appearance of the molded product is poor.

What is particularly important in the present invention is that the fiber length is 0.4 m.
In this case, 5 to 60% by weight, more preferably 10 to 50% by weight, of glass fiber of m or more is left in the molded article. Glass fibers having a fiber length of less than 0.4 mm have little reinforcing effect as long fibers. When the glass fiber content of 0.4 mm or more in the molded article is less than 5% by weight, the reinforcing effect is small, and conversely.
If it exceeds 60% by weight, the molding process is difficult and the appearance of the molded product becomes poor.

Next, preferred uses of the molded article of the present invention will be described, but the uses of the molded article of the present invention are not limited to the following examples. The molded articles of the present invention are classified into antistatic materials, static electricity dissipating materials, and electromagnetic wave shielding materials according to their surface resistivity. Surface resistivity of 1 × 10 for antistatic materials
⁹ to 1 × 10 ¹³ Ω / cm ² , the surface resistivity is 1 × 10 ² to 1 × 10 ⁹ Ω / cm ² for the static electricity dissipating material, and 1 × 10 ⁹ for the electromagnetic wave shielding material. ⁻³ to 1 × 10 ² Ω / cm ² .

The surface resistivity can be adjusted by adding carbon black, carbon fiber, carbon fiber plated with metal such as nickel plating, stainless steel fiber, brass fiber, copper fiber or the like alone or in combination of two or more. Further, the use of the molded article of the present invention will be specifically described. The resin composite of the present invention using carbon black as the conductive material is useful as a material having static electricity dissipation.

As a use of the molded article having the static electricity dissipation property, an IC chip tray is exemplified. Conventionally, for the IC chip tray, polystyrene, polypropylene, or the like containing conductive carbon black has been used. But,
In the case of polypropylene, even when short glass fibers, mica, and various minerals are blended, the heat distortion temperature (HDT), which is an index of heat resistance, is at most 104 to 104 as shown in a comparative example described later.
It was 110 ° C, making it difficult to use at high temperatures.

When the required HDT is about 150 ° C.
As C chip tray material, conventionally, as base resin,
Expensive resins such as heat-resistant modified PPO (polyphenylene oxide), PSU (polysulfone), and PC alloy (alloy of polycarbonate) are used. The molded article of the carbon black-containing glass long fiber polypropylene according to the present invention has a HDT of 150 ° C. or higher because the resin composite is highly reinforced by the glass long fiber.

Therefore, a molded article of carbon black-containing glass long fiber polypropylene can be used for a heat-resistant IC chip tray, and compared with the case of using the above expensive resin.
Cost reduction, industrial and economic significance.
Also, with the rapid spread of mobile phones and personal computers, attention is being paid to electromagnetic wave shielding properties (EMI shielding properties) such as shielding from electromagnetic waves and prevention of leakage of electromagnetic waves.

In order to eliminate the electromagnetic wave interference, the housing of the equipment that generates the electromagnetic wave is made of an EMI shielding material,
When a malfunction occurs due to an external electromagnetic wave, it is required that the housing or the housing be made of an EMI shielding material in order to block the electromagnetic wave. In this case, a conventional resin composite material containing only metal fibers such as stainless steel fiber has insufficient strength and extremely low impact resistance.
It is insufficient to meet the required characteristics of the housing for the MI shield.

On the other hand, the carbon fiber according to the present invention
A long glass fiber reinforced thermoplastic resin molded product containing carbon fiber, stainless steel fiber, brass fiber, copper fiber, etc. plated with metal such as nickel has a heat deformation temperature of 150 ° C or more, Since it is reinforced with, it has excellent tensile strength, flexural strength, flexural modulus and impact resistance.

Further, the molded article of the present invention described above has an EM
Since it has I-shielding properties, it can be preferably applied to members requiring strength, such as an EMI shielding housing and a housing.

[0076]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below based on embodiments. In Examples and Comparative Examples, thermoplastic resin pellets containing glass fiber (hereinafter referred to as LGF), and thermoplastic resin pellets containing glass fiber (: glass long fiber) and a conductive material (hereinafter referred to as LDGF). , Thermoplastic resin pellets containing short glass fibers (hereinafter referred to as SGF),
And four types of thermoplastic resin pellets containing a conductive material (hereinafter referred to as DP) are produced by the following method, respectively, and these pellets are used as a mixture or used alone. The product material was molded by injection molding to obtain a test piece.

[Method of Manufacturing Long Fiber Reinforced Thermoplastic Resin Pellets (LGF):] A glass fiber bundle obtained by heating and melting a thermoplastic resin on a die (glass fiber monofilament φ13 μm treated with an aminosilane coupling agent) ) Was opened and impregnated, cooled and cut to obtain pellets having a length of 9 mm (drawing method).

Table 1 shows the type of thermoplastic resin used, the glass fiber content in the obtained pellets, and the glass fiber length.
-1. As a result of observing the obtained pellet by soft X-ray, the glass fibers were aligned parallel to each other in the pellet, and the length of the glass fiber was substantially the same as that of the pellet.

When the cross section of the pellet was observed, the glass fiber bundle was impregnated with the resin. [Production method of glass fiber (: glass long fiber) reinforced conductive thermoplastic resin pellets (LDGF):] A glass fiber bundle (:
The glass fiber monofilament φ13 μm was impregnated with opening a glass fiber bundle treated with an aminosilane coupling agent), cooled, and then cut to an arbitrary length to obtain a pellet (drawing method).

The polypropylene used was a homo-type polypropylene having a melt flow rate of 40 g / 10 min. Carbon black (Ketjen Black EC) was used as the conductive material. As a result of observing the obtained pellet by soft X-ray, the glass fibers were aligned parallel to each other in the pellet, and the length of the glass fiber was substantially the same as that of the pellet.

When the cross section of the pellet was observed, the glass fiber bundle was impregnated with the resin. Table 1-2 shows the content, glass fiber length, and content of the conductive material in the pellet. [Production method of short glass fiber reinforced thermoplastic resin pellet (SGF):] Thermoplastic resin pellet and chopped glass fiber (glass fiber monofilament φ16 μm, length 15
A twin-screw extruder (CEX-shaped glass fiber whose mm has been treated with an aminosilane coupling agent) (TEX30X, L / D = 42,
The mixture was melt-kneaded and extruded using Nippon Steel Corporation to obtain pellets having a length of 3 mm.

Table 1 shows the type of thermoplastic resin used, the glass fiber content in the obtained pellets, and the glass fiber length.
-1. The cylinder temperature of the extruder is 210 ° C when the resin used is polypropylene, and 180 ° C when the resin used is polystyrene.
The temperature was 300 ° C. for 6,6-nylon and 250 ° C. for 6-nylon.

As the polypropylene, a homo-type polypropylene having a melt flow rate of 40 g / 10 min was used. As 6,6-nylon, Seidel 101 (trade name, manufactured by DuPont) was used. [Production method of conductive pellets (DP):] A twin screw extruder (TEX30X, L / D = 42) is used to extrude thermoplastic resin pellets and conductive material.
, Made by Nippon Steel Corporation), melt-kneaded and extruded,
A 3 mm long pellet was obtained.

Table 1 shows the types of the thermoplastic resin and the conductive material used, and the content of the conductive material in the obtained pellets.
-1. The cylinder temperature of the extruder was 210 ° C. when the resin used was polypropylene, and 300 ° C. when the resin used was 6,6-nylon. As the polypropylene, a homo-type polypropylene having a melt flow rate of 40 g / 10 min was used.

Further, 6,6-nylon is Seidel 101.
(Trade name, manufactured by DuPont) was used. (Examples 1 to 16, Comparative Examples 1 to 15) Various pellets produced by the above method were used in Tables 2-1 to 3-1 and Tables 4-1 and 5-1.
Dry mixing at the ratio shown in -1 and injection molding (mold clamping force 50
t) was performed to obtain ASTM-compliant tensile, bent, and Izod (notched) test pieces.

The materials for thermoplastic resin molded articles in the present example and comparative examples are as follows. Examples 1 to 10 and Examples 14 to 16: Mixtures of long glass fiber reinforced thermoplastic resin pellets and conductive pellets. Comparative Examples 1 to 10, Comparative Examples 13 to 15: Mixtures of short glass fiber reinforced thermoplastic resin pellets and conductive pellets.

Examples 11 to 13 and Comparative Examples 11 and 12: Only glass fiber reinforced conductive thermoplastic resin pellets. Injection molding temperature is 240 when the resin used is polypropylene
℃, 200 ℃ for polystyrene, 25 for 6-nylon
0 ° C, 280 ° C for 6,6-nylon, mold temperature 60 ° C for polypropylene, 70 ° C for polystyrene
C., 100 ° C. for 6-nylon and 6,6-nylon.

The mechanical strength, heat deformation temperature and surface resistivity are A
It was measured according to STM. In addition, pellet molded product is 600 ℃
After firing, measure the weight average glass fiber length using a magnifying glass
did. The weight average glass fiber length l_wIs l_w= Σ
(W_i× l_i) / Σw_i, (W _i: Glass fiber weight,
l_i: Glass fiber length).

Table 2-2 and Table 3 show the obtained performance test results.
-2, Table 4-2 and Table 5-2. Table 2-2, Table 3
-2, as shown in Tables 4-2 and 5-2, the molded article of the present invention has electrical conductivity and is further represented by tensile strength, bending strength, flexural modulus, and Izod impact value. It can be seen that the thermal strength is high and the heat deformation temperature is high and the heat resistance is excellent.

[0090]

[Table 1]

[0091]

[Table 2]

[0092]

[Table 3]

[0093]

[Table 4]

[0094]

[Table 5]

[0095]

[Table 6]

[0096]

[Table 7]

[0097]

[Table 8]

[0098]

[Table 9]

[0099]

[Table 10]

[0100]

The molded article of the present invention has excellent mechanical strength and heat resistance as compared to conventional articles, and has electrical conductivity. For this reason, the molded article of the present invention can be used for electromagnetic shielding materials such as housings and electronic circuit housings that require mechanical strength and heat resistance.
Ideal for applications such as C chip trays.

Further, according to the material for a molded article and the method for producing the molded article of the present invention, the cutting of the glass fiber is prevented, and the dispersion of the glass fiber and the conductive material in the molded article becomes uniform. A molded article having excellent characteristics can be manufactured.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08K 9/08 C08K 9/08 H01B 1/20 H01B 1/20 Z H05K 9/00 H05K 9/00 M

Claims (18)

[Claims] 1. A molded article of a thermoplastic resin containing glass fibers, a conductive material and a thermoplastic resin, wherein the molded article contains 5 to 60% by weight of glass fibers having a length of 0.4 mm or more. Is a thermoplastic resin molded product containing 5 to 75% by weight in total and 3 to 60% by weight of a conductive material. 2. The method according to claim 1, wherein the conductive material is carbon black,
2. A carbon fiber, a stainless steel fiber, a copper fiber and a brass fiber selected from one or more.
The thermoplastic resin molded article according to the above. 3. The method according to claim 1, wherein the thermoplastic resin is a polyolefin resin, a polyamide resin, a polystyrene resin, and A
The thermoplastic resin molded product according to claim 1, wherein the thermoplastic resin molded product is at least one selected from BS resins. 4. The thermoplastic resin molded article according to claim 1, wherein said glass fiber is treated with a coupling agent. 5. A thermoplastic resin molded material material comprising a thermoplastic resin pellet containing a glass fiber bundle and a conductive material, wherein the weight average fiber length of the glass fibers in the thermoplastic resin pellet is 1 mm or more. And, the glass fiber bundle in the thermoplastic resin pellets is impregnated with a thermoplastic resin,
The content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight, and the content of the conductive material is 3 to 60% by weight.
A material for a thermoplastic resin molded product, which is: 6. A thermoplastic resin pellet containing a glass fiber bundle and a conductive material, and a material for a thermoplastic resin molded article containing a thermoplastic resin, wherein the weight average fiber of the glass fibers in the thermoplastic resin pellet is provided. A glass fiber bundle having a length of 1 mm or more and being impregnated with a thermoplastic resin in the thermoplastic resin pellets, wherein the content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight; A material for a thermoplastic resin molded product, wherein the content of the material is 3 to 60% by weight. 7. A thermoplastic resin molding material containing a glass fiber bundle and a thermoplastic resin molded product containing a conductive material, wherein the weight average fiber length of the glass fibers in the thermoplastic resin pellet is 1 mm or more. And the glass fiber bundle in the thermoplastic resin pellets is impregnated with a thermoplastic resin, and the content of all glass fibers in the material for the thermoplastic resin molded product is 5 to 75% by weight, and the content of the conductive material. Is 3 to 60% by weight. 8. A thermoplastic resin molding material containing a thermoplastic resin pellet containing a glass fiber bundle, a conductive material, and a thermoplastic resin, wherein the weight of the glass fiber in the thermoplastic resin pellet. The average fiber length is 1 mm or more, and the glass fiber bundle in the thermoplastic resin pellet is impregnated with a thermoplastic resin, and the content of all glass fibers in the thermoplastic resin molding material is 5 to 75% by weight, A material for a thermoplastic resin molded product, wherein the content of the conductive material is 3 to 60% by weight. 9. The thermoplastic resin pellet has an average length of 1 to 150 mm, the glass fibers in the pellet are aligned in the length direction of the pellet, and the glass fiber has substantially the same length as the pellet. 6. The method according to claim 5, wherein
9. The material for a thermoplastic resin molded product according to any one of items 1 to 8. 10. A thermoplastic resin material comprising glass fiber reinforced thermoplastic resin pellets containing a conductive material, wherein said glass fiber reinforced thermoplastic resin pellets impregnate a glass fiber bundle with a thermoplastic resin. And pellets obtained by cutting, and the glass fibers have substantially the same length as the pellets, the fibers are aligned in parallel, the glass fiber content is 10 to 90% by weight, the fiber direction is A material for a thermoplastic resin molded product, which is a pellet having an average length of 1 to 150 mm. 11. A glass fiber reinforced thermoplastic resin pellet containing a conductive material, and a material for a thermoplastic resin molded article containing a thermoplastic resin, wherein the glass fiber reinforced thermoplastic resin pellet is formed into a glass fiber bundle. A pellet obtained by impregnating and cutting a thermoplastic resin, and wherein the glass fibers have substantially the same length as the pellets, the fibers are aligned in parallel, and the glass fiber content is 10 to 90% by weight. %, Which is a pellet having an average length in the fiber direction of 1 to 150 mm. 12. A thermoplastic resin molded material containing a glass fiber reinforced thermoplastic resin pellet and a conductive material, wherein said glass fiber reinforced thermoplastic resin pellet impregnates a glass fiber bundle with a thermoplastic resin. A pellet obtained by cutting, and the glass fiber has substantially the same length as the pellet, the fibers are aligned in parallel, the glass fiber content is 10 to 90% by weight, the average in the fiber direction. Length 1 to 150
Material for thermoplastic resin molded products, characterized by being pellets of mm. 13. A material for a thermoplastic resin molded article including a glass fiber reinforced thermoplastic resin pellet and a thermoplastic resin pellet containing a conductive material, wherein the glass fiber reinforced thermoplastic resin pellet is a glass fiber bundle. A pellet obtained by impregnating a thermoplastic resin and cutting, and the glass fiber has substantially the same length as the pellet, the fibers are aligned in parallel, and the glass fiber content is 10 to 90. A thermoplastic resin molding material characterized by being a pellet having a weight percentage of 1 to 150 mm in an average length in a fiber direction. 14. A material for a thermoplastic resin molded article containing a glass fiber reinforced thermoplastic resin pellet, a conductive material, and a thermoplastic resin, wherein the glass fiber reinforced thermoplastic resin pellet is heated by a glass fiber bundle. A pellet obtained by impregnating and cutting a plastic resin, and the glass fiber has substantially the same length as the pellet, the fibers are aligned in parallel, and the glass fiber content is 10 to 90% by weight. A thermoplastic resin molding material characterized by being a pellet having an average length in the fiber direction of 1 to 150 mm. 15. The heat according to claim 5, wherein the conductive material is at least one selected from carbon black, carbon fiber, stainless fiber, copper fiber and brass fiber. Material for molded plastic products. 16. The method according to claim 5, wherein the thermoplastic resin is at least one selected from a polyolefin-based resin, a polyamide-based resin, a polystyrene-based resin, and an ABS-based resin. Material for thermoplastic resin molded products. 17. The thermoplastic resin molded product material according to claim 5, wherein the glass fiber bundle is a glass fiber bundle treated with a coupling agent. 18. A method for producing a thermoplastic resin molded article, comprising molding the material for a thermoplastic resin molded article according to any one of claims 5 to 17.