JP6915365B2 - Carbon fiber / polycarbonate resin composite pellet and its manufacturing method - Google Patents

Description

The present invention relates to a carbon fiber / polycarbonate resin composite pellet and a method for producing the same, and in particular, can produce a carbon fiber / polycarbonate resin composite molded product having a high degree of electromagnetic shielding property and excellent strength and rigidity. The present invention relates to a carbon fiber / polycarbonate resin composite pellet that can be produced, and a method for producing the carbon fiber / polycarbonate resin composite pellet by a plutolution method. The present invention also relates to a molded product made of this carbon fiber / polycarbonate resin composite pellet.

Polycarbonate resin is widely used in many fields as a resin having excellent mechanical strength, heat resistance, transparency, dimensional stability and the like. In particular, with the development of the information industry in recent years, the number of cases where it is used as a housing for electrical and electronic equipment is increasing.
In such applications, electromagnetic wave shielding is important in order to prevent the electromagnetic waves generated in the equipment from leaking to the outside and to prevent malfunction due to the intrusion of electromagnetic waves from the outside. Not limited to this, the resin material itself is generally insulating and has no electromagnetic wave shielding property. Therefore, it is necessary to add a conductive substance in order to impart electromagnetic wave shielding properties. There are various types of conductive substances such as carbon black, carbon fiber, and metal fiber. In particular, long carbon fiber is known to provide high electromagnetic shielding properties and also have an excellent reinforcing effect, and is used in automobile applications. Is also expected to be used.

Conventionally, as a method for continuously producing long fiber / resin composite pellets, an electric wire coating method, a plutolution method (for example, Patent Documents 1 and 2), and a direct roving method are known.

These methods will be described below with reference to FIGS. 6 (a) to 6 (c).
In FIGS. 6A to 6C, 1 is an extruder, 2 is a hopper, 3 is a screw, 4 is a crosshead die, 4A is a die, 5 is a water tank, 6 is a take-up roll, 7 is a cutter, and 8 is a mesh. Conveyor 9 is a vent port of extruder 1.
In either method, the resin pellets 11 are charged from the hopper 2 of the extruder 1, melt-kneaded with the screw 3, and then extruded from the crosshead die 4 or the die 4A together with the long fiber bundle (roving) 12.

In the electric wire coating method, as shown in FIG. 6A, the long fiber bundle (roving) 12 is sent out to the crosshead die 4, the long fiber bundle 12 is coated with the molten resin from the screw 3, and the resin-coated long fiber bundle is coated. 13 is obtained, which is cooled in the water tank 5 and then cut with a cutter 7 to obtain long fiber / resin composite pellets 13A.

In the plutolusion method, as shown in FIG. 6 (b), the long fiber bundle (roving) 12 is sent out from above the cross head die 4, and the long fiber bundle is formed by an impregnated roll (not shown) provided in the cross head die 4. By widening and loosening in a band shape, molten resin is impregnated between the fibers in the long fiber bundle to obtain a resin-impregnated long fiber bundle 14, which is cooled in a water tank 5 and then cut with a cutter 7 to obtain long fibers /. A resin composite pellet 14A is obtained.

In the direct roving method, as shown in FIG. 6 (c), the long fiber bundle (roving) 12 is directly introduced from the vent port 9 of the extruder 1 to obtain the resin composite long fiber 15, which is water-cooled on the mesh conveyor 8. After that, it is cut with a cutter 7 to obtain a long fiber / resin composite pellet 15A.

Among the conventional methods for producing long fiber / resin composite pellets, in the direct roving method, since the long fiber bundle is directly supplied to the extruder from the vent port, the fibers are broken in the extruder, and the fiber length is fully utilized. Long fiber / resin composite pellets cannot be produced.

The electric wire coating method and the plutolution method are preferable in that the fiber length in the pellet can be left long. However, in the electric wire coating method, the circumference of the long fiber bundle is only coated with resin, so that the obtained pellet is obtained. The fiber is easy to come off from.

The plution method in which the resin is impregnated between the fibers of the long fiber bundle is preferable in that the fibers are hard to come off from the pellets, but a carbon fiber / polycarbonate resin composite pellet obtained by the plutrlusion method can also be obtained. At present, the electromagnetic shielding properties, strength, and rigidity of molded products are not sufficient, and further improvement is desired.

Japanese Unexamined Patent Publication No. 1-166112 Japanese Unexamined Patent Publication No. 5-169445

The present invention has been made in view of the above-mentioned conventional circumstances, and is capable of producing a carbon fiber / polycarbonate resin composite molded product having a high degree of electromagnetic shielding property and excellent strength and rigidity. An object of the present invention is to provide a fiber / polycarbonate resin composite pellet.

As a result of diligent studies to solve the above problems, the present inventor uses a continuous carbon long fiber bundle used as a carbon fiber raw material in a carbon fiber / polycarbonate resin composite pellet treated with a specific converging agent. As a result, the interfacial adhesion between the polycarbonate resin and the carbon fiber can be enhanced, and the impregnation property and dispersibility of the carbon fiber in the resin are improved, so that the carbon fiber / polycarbonate resin composite obtained by molding the carbon fiber / polycarbonate resin composite can be improved. It has been found that the molded product has excellent electromagnetic shielding properties, and has high strength and high rigidity.
That is, the gist of the present invention is as follows.

[1] A carbon fiber / polycarbonate resin composite pellet containing 10 to 100 parts by mass of carbon fibers (B) with respect to 100 parts by mass of the polycarbonate resin (A), wherein the carbon fibers (B) are epoxy / urethane-based or It is made from a continuous carbon long fiber bundle (b) treated with a polyester-based converging agent, and is characterized in that the mass average fiber length of the carbon fibers (B) in the pellet is in the range of 3000 to 10000 μm. Carbon fiber / polycarbonate resin composite pellets.

[2] The carbon fiber / polycarbonate resin composite pellet according to [1], further containing 1 to 25 parts by mass of the flow improver (C) with respect to 100 parts by mass of the polycarbonate resin (A).

[3] The carbon fiber / polycarbonate resin composite pellet according to [2], wherein the flow improver (C) is a polycarbonate oligomer or an acrylonitrile-styrene copolymer.

[4] The long fiber bundles of carbon fibers are continuously run in the molten resin bath of the polycarbonate resin, and the long fiber bundles are widened in a band shape with an impregnated roll in the molten resin bath. A process of manufacturing a carbon long fiber / polycarbonate resin composite material by impregnating a long fiber bundle with a resin and taking the resin impregnated long fiber bundle from the molten resin bath, and cutting the manufactured carbon long fiber / polycarbonate resin composite material. A method for producing a carbon fiber / polycarbonate resin composite pellet, which comprises a step of obtaining a carbon fiber / polycarbonate resin composite pellet containing the polycarbonate resin (A) and the carbon fiber (B), wherein the molten resin temperature is 290 to 340. Production of carbon fiber / polycarbonate resin composite pellets at ° C., wherein the long fiber bundle of the carbon fiber is a continuous carbon long fiber bundle (b) treated with an epoxy / urethane-based or polyester-based converging agent. Method.

[5] The method for producing a carbon fiber / polycarbonate resin composite pellet according to [4], wherein the pellet cutting length of the carbon long fiber / polycarbonate resin composite material is 3 to 10 mm.

[6] In [4] or [5], the carbon fiber / polycarbonate resin composite pellet contains 10 to 100 parts by mass of carbon fiber (B) with respect to 100 parts by mass of the polycarbonate resin (A), and further improves the flow. A method for producing a carbon fiber / polycarbonate resin composite pellet, which comprises 1 to 25 parts by mass of the agent (C) with respect to 100 parts by mass of the polycarbonate resin (A).

[7] The method for producing a carbon fiber / polycarbonate resin composite pellet according to [6], wherein the flow improver (C) is a polycarbonate oligomer.

[8] A molded product obtained by injection molding the carbon fiber / polycarbonate resin composite pellet according to any one of [1] to [3].

According to the carbon fiber / polycarbonate resin composite pellet of the present invention, it is possible to produce a carbon fiber / polycarbonate resin composite molded product having a high degree of electromagnetic shielding property and also having excellent strength and rigidity. Further, according to the method for producing a carbon fiber / polycarbonate resin composite pellet of the present invention, such a carbon fiber / polycarbonate resin composite pellet can be produced efficiently and non-remainingly by the plutolution method.

It is a schematic plan view which shows an example of the manufacturing apparatus of CF / PC pellet suitable for carrying out this invention. (A) is a schematic cross-sectional view of a resin-impregnated cell and a preheating cell portion of the CF / PC pellet manufacturing apparatus of FIG. 1, and (b) is a schematic view showing the arrangement of an impregnated roll and a guide roll. be. FIG. 5 is a schematic plan view showing another example of a CF / PC pellet manufacturing apparatus suitable for carrying out the present invention. (A) is a schematic cross-sectional view of a resin-impregnated cell and a preheating cell portion of the CF / PC pellet manufacturing apparatus of FIG. 3, and (b) is a schematic view showing the arrangement of an impregnated roll and a guide roll. be. It is a figure which shows the arrangement example of the impregnation roll, (a) is a front view, (b) is a side view. It is a schematic diagram which shows the manufacturing method of the conventional long fiber / resin composite pellet, (a) figure shows the electric wire coating method, (b) figure shows a pull lution method, and (c) figure shows a direct roving method, respectively. ..

Embodiments of the present invention will be described in detail below.

[Carbon fiber / Polycarbonate resin composite pellet]
The carbon fiber / polycarbonate resin composite pellet of the present invention (hereinafter, may be referred to as “CF / PC pellet”) contains 10 to 100 parts by mass of carbon fiber (B) with respect to 100 parts by mass of the polycarbonate resin (A). The CF / PC pellet is made from a continuous carbon long fiber bundle (b) treated with an epoxy / urethane-based or polyester-based converging agent, and the carbon in the pellet is carbon. The fiber (B) is characterized in that the mass average fiber length is in the range of 3000 to 10000 μm.

<Continuous carbon long fiber bundle (b)>
First, the continuous carbon long fiber bundle (b) used as the raw material for the carbon fiber (B) of the CF / PC pellet of the present invention will be described.

The continuous carbon long fiber bundle (b) used in the present invention is a continuous carbon long fiber that has been treated with an epoxy / urethane-based or polyester-based convergent to converge. That is, as the converging agent for the continuous carbon long fiber bundle, various ones such as epoxy / urethane type, polyester type, epoxy type, polyether type, polyamide type, urethane type and the like are generally provided. As a result of the examination by the inventor, if the continuous carbon long fiber bundle (b) using the epoxy / urethane-based converging agent or the polyester-based converging agent has excellent adhesion to the polycarbonate resin, and has good impregnation property and dispersibility in the resin. Therefore, it has been found that a molded product having high electromagnetic shielding properties and excellent strength and rigidity can be obtained.

The carbon fibers constituting the continuous carbon long fiber bundle (b), that is, the carbon fibers (B) in the CF / PC pellets include polyacrylonitrile (PAN) type, petroleum / petroleum pitch type, rayon type, lignin type and the like. Any carbon fiber may be used, but PAN-based carbon fiber made from PAN is particularly preferable because it has excellent mechanical properties and is easily available.

The fiber diameter (filament diameter per filament) of the carbon fiber (B) is preferably 10 μm or less, more preferably 9 μm or less, still more preferably 8 μm or less, and among them, 7.5 μm or less. In particular, it is preferably 7.0 μm or less, further 6.5 μm or less, particularly 6 μm or less, preferably 3 μm or more, more preferably 3.5 μm or more, still more preferably 4 μm or more. It is particularly preferably 5 μm or more. When the fiber diameter is in such a range, the strength of the obtained molded product, particularly the elastic modulus, is further improved, and it becomes easy to obtain a molded product having excellent electromagnetic wave shielding properties. Here, the fiber diameter of the carbon fiber (B) means a number average fiber diameter, but most of the commercially available carbon fibers of the continuous carbon long fiber bundle have a uniform fiber diameter. Once the fiber diameter is determined, a product having an almost uniform fiber diameter can be obtained from commercially available products.

The continuous carbon long fiber bundle (b) is preferably a long fiber bundle in which about 1000 to 50,000 carbon fibers (1 to 50 k) having such a fiber diameter are converged with an epoxy / urethane-based or polyester-based converging agent. ..

The amount of the epoxy / urethane-based or polyester-based converging agent in the continuous carbon long fiber bundle (b) is preferably 0.5 to 3% by mass with respect to 100% by mass of the total of the long carbon fibers and the converging agent. ..

<Polycarbonate resin (A)>
As the polycarbonate resin (A) contained in the CF / PC pellet of the present invention, any conventionally known polycarbonate resin can be used. Examples of the polycarbonate resin (A) include aromatic polycarbonate resin, aliphatic polycarbonate resin, and aromatic-aliphatic polycarbonate resin, and aromatic polycarbonate resin is preferable.

The aromatic polycarbonate resin is a optionally branched aromatic polycarbonate polymer obtained by reacting an aromatic hydroxy compound with a diester of phosgene or carbonic acid. The method for producing the aromatic polycarbonate resin is not particularly limited, and a conventional method such as a phosgene method (interfacial polymerization method) or a melting method (transesterification method) can be used. Further, it may be a polycarbonate resin produced by a melting method and produced by adjusting the amount of OH groups of the terminal groups.

Typical examples of the aromatic dihydroxy compound, which is one of the raw materials for the aromatic polycarbonate resin used in the present invention, are bis (4-hydroxyphenyl) methane and 2,2-bis (4-hydroxyphenyl). Propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-t-butylphenyl) propane, 2,2-bis (4-hydroxy-3, 5-Dimethylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (4-hydroxyphenyl) Cyclohexane, 4,4'-dihydroxybiphenyl, 3,3', 5,5'-tetramethyl-4,4'-dihydroxybiphenyl, bis (4-hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) sulfide, bis Examples thereof include (4-hydroxyphenyl) ether and bis (4-hydroxyphenyl) ketone.
Further, a polyhydric phenol having three or more hydroxy groups in a molecule such as 1,1,1-tris (4-hydroxyphenyl) ethane, 1,3,5-tris (4-hydroxyphenyl) benzene is branched. It can also be used in small amounts as an agent.
Among these aromatic dihydroxy compounds, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A) is preferable. These aromatic dihydroxy compounds can be used alone or in combination of two or more.

To obtain a branched aromatic polycarbonate resin, fluoroglucin, 4,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) hepten-2, 4,6-dimethyl-2,4,6-tris ( 4-Hydroxyphenyl) heptane, 2,6-dimethyl-2,4,6-tris (4-hydroxyphenyl) heptene-3,1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1 -Polyhydroxy compounds such as tris (4-hydroxyphenyl) ethane, or 3,3-bis (4-hydroxyaryl) oxyindole (= isatin bisphenol), 5-chloruisatin, 5,7-dichlorousatin, 5-bromuisatin, etc. May be used as a part of the aromatic dihydroxy compound, and the amount used thereof is 0.01 to 10 mol%, preferably 0.1 to 2 mol%, based on the hydroxy compound.

In polymerization by the transesterification method, a carbonic acid diester is used as a monomer instead of phosgene. Typical examples of carbonic acid diesters include substituted diaryl carbonates typified by diphenyl carbonate, ditril carbonate and the like, dialkyl carbonates typified by dimethyl carbonate, diethyl carbonate, di-tert-butyl carbonate and the like. These carbonic acid diesters can be used alone or in admixture of two or more. Among these, diphenyl carbonate and substituted diphenyl carbonate are preferable.

Further, the above-mentioned carbonic acid diester may be replaced with a dicarboxylic acid or a dicarboxylic acid ester in an amount of preferably 50 mol% or less, more preferably 30 mol% or less. Typical dicarboxylic acids or dicarboxylic acid esters include terephthalic acid, isophthalic acid, diphenyl terephthalate, diphenyl isophthalate and the like. When substituted with such a dicarboxylic acid or dicarboxylic acid ester, a polyester carbonate is obtained.

When producing an aromatic polycarbonate resin by the transesterification method, a catalyst is usually used. The type of catalyst is not limited, but generally, basic compounds such as alkali metal compounds, alkaline earth metal compounds, basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds are used. Of these, alkali metal compounds and / or alkaline earth metal compounds are particularly preferable. These may be used alone or in combination of two or more. In the transesterification method, it is common to inactivate the polymerization catalyst with a p-toluenesulfonic acid ester or the like.

Preferred as the polycarbonate resin (A) are aromatic polycarbonate resins derived from 2,2-bis (4-hydroxyphenyl) propane or 2,2-bis (4-hydroxyphenyl) propane and other aromatic dihydroxy compounds. Examples thereof include aromatic polycarbonate copolymers derived from. Further, a polymer or oligomer having a siloxane structure can be copolymerized for the purpose of imparting flame retardancy and the like. The polycarbonate resin (A) may be a mixture of two or more kinds of polymers and / or copolymers having different raw materials, and may have a branched structure up to 0.5 mol%.

The content of the terminal hydroxyl group of the polycarbonate resin (A) such as the aromatic polycarbonate resin has a great influence on the thermal stability, the hydrolysis stability, the color tone and the like. In order to have practical physical properties, the terminal hydroxyl group content of the polycarbonate resin (A) is usually 30 to 2000 ppm, preferably 100 to 1500 ppm, more preferably 200 to 1000 ppm, and the terminal hydroxyl group content is adjusted. As the sealing end agent to be adjusted, p-tert-butylphenol, phenol, cumylphenol, p-long-chain alkyl-substituted phenol and the like can be used.

The amount of residual monomer in the polycarbonate resin (A) such as the aromatic polycarbonate resin is 150 ppm or less, preferably 100 ppm or less, and more preferably 50 ppm or less for the aromatic dihydroxy compound. When synthesized by the transesterification method, the residual amount of carbonic acid diester is 300 ppm or less, preferably 200 ppm or less, and more preferably 150 ppm or less.

The molecular weight of the polycarbonate resin (A) such as the aromatic polycarbonate resin is a viscosity average molecular weight converted from the solution viscosity measured at a temperature of 20 ° C. using methylene chloride as a solvent, and is preferably in the range of 13,000 to 50,000. It is more preferably more than 13,000 and less than 40,000, and particularly preferably in the range of 18,000 to 30,000. By setting the viscosity average molecular weight to 13,000 or more, the mechanical properties of the obtained CF / PC pellets and the molded product obtained by using the pellets are more effectively exhibited, and by setting the viscosity to 50,000 or less. , The molding processability of the obtained CF / PC pellets becomes better. Further, two or more kinds of polycarbonate resins having different viscosity average molecular weights may be mixed, or polycarbonate resins having a viscosity average molecular weight outside the above preferable range may be mixed to bring them within the above molecular weight range.

Further, the polycarbonate resin (A) used in the present invention may be not only a polycarbonate resin as a virgin raw material but also a polycarbonate resin regenerated from a used product, that is, a so-called material recycled polycarbonate resin. Used products include optical recording media such as optical disks, light guide plates, automobile windowpanes and automobile headlamp lenses, vehicle transparent members such as windshields, containers such as water bottles, eyeglass lenses, soundproof walls and glass windows, and waves. Building members such as boards are preferably mentioned. Further, the form of the recycled polycarbonate resin is not particularly limited, and any non-conforming product, a crushed product such as a sprue or a runner, and pellets obtained by melting them can be used.

<Carbon fiber (B) content and mass average fiber length>
The content of the carbon fiber (B) in the CF / PC pellet of the present invention is 10 to 100 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A).
If the carbon fiber (B) content of the CF / PC pellets is higher than the above upper limit, the moldability and impact resistance of the CF / PC pellets and the molded product obtained by molding the CF / PC pellets will be inferior. In addition, the amount of resin is relatively small, and there is a risk that fibers may fall off. On the contrary, if the carbon fiber (B) content is less than the above lower limit, sufficient electromagnetic wave shielding property, strength, and rigidity cannot be obtained for the obtained molded product.

The carbon fiber (B) content of the CF / PC pellet of the present invention is preferably 13 parts by mass or more, more preferably 15 parts by mass or more, and preferably 80 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). It is less than or equal to parts, more preferably 70 parts by mass or less, still more preferably 60 parts by mass or less, and particularly preferably 50 parts by mass or less, particularly 40 parts by mass or less, and particularly preferably 30 parts by mass or less.

The mass average fiber length of the carbon fibers (B) in the CF / PC pellets of the present invention is in the range of 3000 to 10000 μm (3 to 10 mm). If the mass average fiber length of the carbon fibers (B) is less than 3000 μm, a molded product having sufficiently excellent electromagnetic wave shielding properties cannot be obtained, and the carbon fibers may fall off from the pellets. On the contrary, when the mass average fiber length of the carbon fiber (B) exceeds 10000 μm, the fluidity at the time of molding is deteriorated and the moldability is impaired. The mass average fiber length of the carbon fibers (B) in the CF / PC pellets of the present invention is preferably 4000 to 9000 μm (4 to 9 mm), more preferably 5000 to 8000 μm (5 to 8 mm).

The CF / PC pellet in which the mass average fiber length of the carbon fibers (B) in the pellet is in the above range has a cutting length of 3, for example, in the method for producing CF / PC pellets of the present invention by the plutolution method described later. It can be produced by setting the thickness to 10 mm, preferably 4 to 9 mm, and more preferably 5 to 8 mm. If the cutting length is less than 3 mm, the electromagnetic wave shielding property and rigidity are not obtained, and if it exceeds 10 mm, molding defects such as poor bite may occur during molding.

<Fluid modifier (C)>
The CF / PC pellet of the present invention is a flow modifier (in order to improve fluidity and moldability, to improve the surface appearance of the obtained molded product, and to leave a long carbon fiber length in the molded product. It is preferable to contain C). The flow improver (C) is a component that improves the fluidity of the polycarbonate resin (A), and various low molecular weight compounds or high molecular weight compounds can be used. Particularly preferred as the flow improver (C) used in the present invention is one or a combination of two or more selected from acrylonitonyl-styrene copolymer, polycarbonate oligomer and polycaprolactone, and among them, acrylonitonyl-styrene copolymer. Alternatively, a polycarbonate oligomer is preferable, and a polycarbonate oligomer is particularly preferable.

The acrylonitrile-styrene copolymer is a thermoplastic copolymer obtained by copolymerizing a vinyl cyanide compound and an aromatic vinyl compound. Here, examples of the vinyl cyanide compound include vinyl cyanide compounds such as acrylonitrile and methacrylonitrile, and acrylonitrile is particularly preferable. Examples of the aromatic vinyl compound include styrene and styrene derivatives such as styrene, α-methylstyrene, p-methylstyrene, vinylxylene, dimethylstyrene, pt-butylstyrene, bromostyrene and dibromostyrene. Of these, styrene is preferable. It should be noted that these can be used alone or in combination of two or more.

As a preferable ratio of each of the structural units derived from the vinyl cyanide compound and the aromatic vinyl compound in the acrylonitrile-styrene copolymer, the structural units derived from the vinyl cyanide compound are 10 to 40 when the whole is 100% by mass. It is by mass, more preferably 15 to 30% by mass, and the structural unit derived from the aromatic vinyl compound is 90 to 60% by mass, more preferably 85 to 70% by mass. Further, at the time of copolymerization, it is also possible to mix and use other copolymerizable vinyl-based compounds with these vinyl compounds, and the mixing ratio thereof is the above-mentioned other vinyl-based compounds in the acrylonitrile-styrene copolymer. The structural unit derived from the compound is preferably 15% by mass or less. Further, as the initiator, chain transfer agent and the like used in the copolymerization reaction, known ones can be used as needed.

The acrylonitrile-styrene copolymer is produced by a method such as emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization or bulk / suspension polymerization, but any method may be used.
The melt flow rate (MFR) reflecting the molecular weight of the acrylonitrile-styrene copolymer is preferably 5 to 50 g / 10 minutes at 220 ° C. and a load of 10 kg, and more preferably 10 to 30 g / 10 minutes.

As the acrylonitrile-styrene copolymer, those commercially available as AS resin or SAN resin can be widely adopted.

The polycarbonate oligomer is preferably 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3, 5-Dibromophenyl) Obtained by a reaction between an aromatic dihydric phenolic compound typified by propane and a carbonate precursor typified by phosgen, or an ester exchange reaction between an aromatic dihydric phenol and diphenyl carbonate or the like. , The aromatic dihydric phenolic compound may be used alone or in combination.

The polycarbonate oligomer preferably has an average degree of polymerization of 2 to 15. If the average degree of polymerization of the polycarbonate oligomer is less than 2, it tends to be difficult to prevent bleeding out from the molded product during molding, and if the average degree of polymerization exceeds 15, the appearance of the obtained molded product may deteriorate. To adjust the degree of polymerization of the polycarbonate oligomer, in the interfacial polymerization method using phosgene, phenol and / or alkyl-substituted phenol may be added to the polymerization system to seal the ends.

Polycaprolactone is a polymer of caprolactone, especially ε-caprolactone, that is, it has a repeating unit of _{[-CH 2-} CH _2- CH _2- CH _2- CH _{2-CO-O-], and is contained in the polymer.} A polymer or copolymer containing at least 70% by mass or more, preferably 75% by mass or more, and more preferably 80% by mass or more of such a structural unit. When the polycaprolactone is a copolymer of ε-caprolactone and another monomer, the monomer copolymerizing with ε-caprolactone includes a lactone monomer such as β-propiolactone, pivalolactone, butyrolactone, ethylene oxide, and the like. Examples thereof include 1,2-propion oxide, alkylene oxides such as 1,3-propylene oxide and tetrahydrofuran, unsaturated monomers such as styrene, methyl methacrylate and butadiene, and coupling agents such as dimethyl terephthalate and diphenyl carbonate. One of these may be used alone, or two or more thereof may be mixed and used. A part of the hydrogen atom of the methylene chain of polycaprolactone may be substituted with a halogen atom or a hydrocarbon group, and the terminal of polycaprolactone may be terminally treated by esterification, etherification or the like. ..

The number average molecular weight of polycaprolactone is a polystyrene-equivalent number average molecular weight obtained by gel permeation chromatography (GPC), preferably 4000 to 50,000, more preferably 5,000 to 40,000, and further preferably 8,000 to 30,000.
The method for producing polycaprolactone is not particularly limited, but a method of ring-opening polymerization of ε-caprolactone using an appropriate initiator such as alcohol, glycol or water and a catalyst such as titanium tetrabutoxide or tin chloride is used.

When the CF / PC pellet of the present invention contains the flow improver (C), the content of the flow modifier (C) is 1 to 25 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). It is more preferably 5 parts by mass or more, further preferably 10 parts by mass or more, still more preferably 20 parts by mass or less, and further preferably 18 parts by mass or less. When the content of the flow modifier (C) is less than the above lower limit, the effect of improving the moldability by improving the fluidity by blending the fluidity modifier (C) and leaving the residual fiber length in the molded product for a long time. It is not possible to sufficiently obtain the effect of improving the electromagnetic wave shielding property and rigidity and the effect of improving the surface appearance, and if it exceeds the above upper limit, the heat resistance and impact resistance tend to decrease, and the appearance is liable to deteriorate. ..

<Inorganic conductive substance>
The CF / PC pellet of the present invention may contain an inorganic conductive substance.
As the inorganic conductive substance, a known inorganic conductive substance usually blended in a thermoplastic resin can be used, and the carbon fiber (B) can be used in the molded product obtained by using the inorganic conductive substance. By further continuing the network formed by the above with the intervention of an inorganic conductive substance, even better electromagnetic shielding properties can be obtained. Examples of such inorganic conductive substances include carbon-based conductive substances such as carbon black, carbon fibers, graphite, carbon whiskers, and carbon nanotubes, metal powders such as SUS powder, and metal-based inorganic conductivity such as metal oxides. Examples thereof include substances, carbon fibers, whiskers, and composite conductive substances in which the surface of glass fibers is coated with metal. Among these, metal powders such as conductive carbon black, carbon nanotubes, and SUS powder are preferable. One of these inorganic conductive substances may be used alone, or two or more thereof may be used in combination.

As the conductive carbon black, one having a large specific surface area and a developed secondary aggregate (structure) is generally preferable, and the specific surface area (BET type nitrogen adsorption method) is 30 to 1500 m ² / g, particularly 50 to 1300 m ² /. g, more preferably 70 to 900 m ² / g, particularly 100 to 850 m ² / g. If the specific surface area ^{exceeds 1500 m 2} / g, the fluidity and appearance of the obtained CF / PC pellets and the molded product obtained by using the pellets tend to deteriorate, and if ^{it is less than 30 m 2} / g, the conductivity tends to deteriorate. It may be difficult to develop.

As the conductive carbon black having a dibutylphthalate (DBP) absorption of preferably has a 100~500cm ³ / 100g, among others 120~450cm ³ / 100g, those which are particularly 150~400cm ³ / 100g, conductive It is more preferable in terms of the balance between property and impact resistance.

In the present invention, BET equation nitrogen adsorption method specific surface area ^(unit: m 2 / g), DBP absorption ^(unit: cm 3 / 100g) are those measured according to JIS K6217.

Such preferable conductive carbon blacks include the furnace method conductive carbon black that thermally decomposes the raw material hydrocarbons by the heat of combustion of crude oil and gas to produce carbon black, and the acetylene obtained by the gasification process of heavy oil. Examples include black and acetylene black obtained by thermally decomposing acetylene gas. For example, "Vulcan XC-72" manufactured by Cabot, "Ketchen Black EC" manufactured by Mitsubishi Chemical Co., Ltd., and "Denka" manufactured by Electrochemical Industry Co., Ltd. "Black" etc. are commercially available.

One type of conductive carbon black may be used alone, or two or more types having different physical characteristics, raw materials, or manufacturing processes may be mixed and used.

The carbon nanotube is a carbon fibril having a hollow structure, and preferably has an outer diameter of 3.5 to 70 nm and an aspect ratio of 5 or more, and particularly preferably an outer diameter of 4 to 60 nm and an aspect ratio of 10 or more. Those having a fibril outer diameter of less than 3.5 nm tend to be inferior in dispersibility in the resin, and those having a fibril outer diameter of more than 70 nm tend to be inferior in conductivity. Further, when the aspect ratio is less than 5, the conductivity tends to be inferior.

Carbon nanotubes have an outer region consisting of an essentially continuous multi-layer of regularly arranged carbon atoms and an inner hollow region, each layer and the hollow region substantially around the cylindrical axis of the fibril. Cylindrical fibrils arranged concentrically with each other. Further, it is preferable that the regularly arranged carbon atoms in the outer region are graphite-like and the diameter of the hollow region is 2 to 20 nm. Such carbon nanotubes are described in detail in Japanese Patent Publication No. 62-590413 and US Pat. No. 4,663,230. Regarding the manufacturing method, as described in the above patent gazette and the US patent specification, transition metal-containing particles (for example, iron, cobalt, nickel-containing particles having alumina as a support) contain carbon such as CO and hydrocarbons. Examples thereof include a method in which carbon generated by thermal decomposition is brought into contact with a gas at a high temperature of 850 to 1200 ° C. and grown into a fibrous form starting from a transition metal. Such carbon nanotubes are commercially available from Hyperion Catalysis under the trade name of "graphite fibril" and are easily available.

Examples of the metal powder include powders such as gold, silver, copper, nickel, magnesium, zinc, aluminum, iron, and alloys containing two or more of these metals. Among these, SUS powder is particularly electromagnetic shield. It is preferable in terms of the effect of imparting sex and the cost.
Although it is difficult for metal powders such as SUS powder to impart electromagnetic wave shielding properties by themselves, high electromagnetic wave shielding properties can be imparted when used in combination with long carbon fibers.

The shape of the metal powder is not particularly limited, such as rod-like fibers or the like, spherical particles, flakes (scales), etc. However, if the particle size is too large, the moldability and mechanical strength of the pellets may be impaired. If it is too small, the electromagnetic wave shielding effect tends to be inferior. Therefore, the average particle size is preferably 1 to 1000 μm, particularly preferably about 10 to 500 μm. Here, the particle size of the metal powder is the length of the long side of the rod-shaped metal powder, the diameter of the spherical metal powder, and the largest diameter of the granular metal powder. Corresponds to the diameter of the part.

Only one type of metal powder may be used, or two or more types having different materials, sizes, and shapes may be used in combination.

When the above-mentioned inorganic conductive substance, particularly an inorganic conductive substance such as a carbon-based conductive substance, is contained in the CF / PC pellet of the present invention, the inorganic conductive substance is 100% by mass of the polycarbonate resin (A). With respect to parts, preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, further preferably 2 parts by mass or more, preferably 20 parts by mass or less, more preferably 15 parts by mass or less, still more preferably 12 parts. It is preferable to use it so that it is less than a part by mass. If the blending amount of the inorganic conductive substance is less than the above lower limit value, the effect of improving the electromagnetic wave shielding property by using the inorganic conductive substance cannot be sufficiently obtained, and if it exceeds the above upper limit value, the CF / PC pellets obtained. There is a risk that moldability and the like will be impaired.

Further, among the inorganic conductive substances, particularly when a metal powder such as SUS powder is contained in the CF / PC pellet of the present invention, the metal powder is preferably 5 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A). As described above, it is more preferably 7 parts by mass or more, further preferably 10 parts by mass or more, preferably 100 parts by mass or less, more preferably 90 parts by mass or less, still more preferably 80 parts by mass or less. If the blending amount of the metal powder is less than the above lower limit value, the effect of improving the electromagnetic wave shielding property by using the metal powder cannot be sufficiently obtained, and if the above upper limit value is exceeded, the moldability of the CF / PC pellets obtained is improved. It may be damaged.

Inorganic conductive substances such as carbon black, carbon nanotubes, and metal powder are preferably blended as a masterbatch containing them in a high concentration because the inorganic conductive substances can be uniformly dispersed in the resin. In this case, the resin used for the master batch may be the same polycarbonate resin as the polycarbonate resin (A) used for the CF / PC pellet of the present invention, may be a different polycarbonate resin, and may be a resin other than the polycarbonate resin. For example, it may be a polystyrene resin or the like. The content of the inorganic conductive substance such as carbon black, carbon nanotubes, and metal powder in the masterbatch is not particularly limited, but is usually about 20 to 50% by mass.
When these master batches contain a polycarbonate resin, the polycarbonate resin is also used as the polycarbonate resin (A) in the CF / PC pellets of the present invention, as described above for the carbon fiber (B), the flow improver (C), and the inorganic conductivity. It is contained in the polycarbonate resin (A), which is a reference for the numerical value of the blending amount of the substance and various additives described later.

<Other thermoplastic resins>
The CF / PC pellet of the present invention may contain a thermoplastic resin other than the polycarbonate resin (A). In this case, the type and blending amount can be appropriately selected for the purpose of improving performance such as moldability and chemical resistance. Examples of the thermoplastic resin other than the polycarbonate resin (A) include polyester resin, polyamide resin, polyolefin resin, polyphenylene ether resin, styrene resin, polysulfone, polyethersulfone, polyphenylene sulfide, polyacrylate, polyamideimide, polyetherimide and the like. Can be mentioned.

Examples of the polyester resin include polybutylene terephthalate, polyethylene terephthalate, polybutylene naphthalate, and polyethylene naphthalate. Examples of the polyolefin resin include polyethylene and polypropylene. Examples of the polyphenylene ether-based resin include a polyphenylene ether resin and a mixed resin of polyphenylene ether and polystyrene and / or HIPS (impact resistant polystyrene). Examples of the styrene resin include polystyrene, HIPS, AS resin, ABS resin and the like. Preferred examples of the thermoplastic resin other than the polycarbonate resin (A) include polybutylene terephthalate, polyethylene terephthalate, polyphenylene ether-based resin, HIPS, AS resin, and ABS resin.

When the CF / PC pellet of the present invention contains a thermoplastic resin other than the polycarbonate resin (A), the blending amount thereof is preferably the total amount of the polycarbonate resin (A) and the thermoplastic resin other than the polycarbonate resin (A). It is less than 50% by mass, more preferably 40% by mass or less, and most preferably 30% by mass or less.

<Additives>
In order to obtain desired physical properties, the CF / PC pellet of the present invention has various additives such as UV absorbers, antioxidants, stabilizers such as heat stabilizers, pigments, dyes, lubricants, and difficulties. A fuel agent, a drip inhibitor, a mold release agent, a slidability improver and the like can be blended.

(Antioxidant)
Examples of the antioxidant include a hindered phenolic antioxidant. Specific examples thereof include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl). ) Propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N'-hexane-1,6-diylbis [3- (3,5-di-) tert-Butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl) ] Methyl] Phenolate, 3,3', 3 ", 5,5', 5" -Hexa-tert-butyl-a, a', a "-(mesitylen-2,4,6-triyl) tri-p- Cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3 -(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert-butyl-4-hydroxybenzyl) -1,3,5- Triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazine-2-ylamino ) Phenol and the like. These may be used in combination of two or more.

Among the above, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) Propionate is preferred. These two phenolic antioxidants are commercially available from Ciba Specialty Chemicals under the names "Irganox 1010" and "Irganox 1076".

When the CF / PC pellet of the present invention contains an antioxidant, the blending amount thereof is usually 0.001 to 1 part by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is preferably 0.01 to 0.5 parts by mass. If the blending amount of the antioxidant is less than 0.001 part by mass, the effect as an antioxidant is insufficient, and if it exceeds 1 part by mass, the effect reaches a plateau and is not economical.

(Heat stabilizer)
As heat stabilizers, phosphite ester compounds in which at least one ester in the molecule is phenol and / or phenol esterified with at least one alkyl group having 1 to 25 carbon atoms, phosphorous acid, and tetrakis ( At least one selected from the group of 2,4-di-tert-butylphenyl) -4,4'-biphenylene-di-phosphonite can be mentioned.

Specific examples of the above phosphite compound include trioctyl phosphite, tridecyl phosphite, triphenyl phosphite, trisnonylphenyl phosphite, tris (octylphenyl) phosphite, and tris (2,4-di-). tert-Butylphenyl) Phenylphosphite, Tridecylphosphite, Didecylmonophenylphosphite, Dioctylmonophenylphosphite, Diisopropylmonophenylphosphite, Monobutyldiphenylphosphite, Monodecyldiphenylphosphite, Monooctyldiphenylphosphite, Distearyl pentaerythritol diphosphite, diphenylpentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,2-methylenebis (4,6-di-) tert-butylphenyl) octylphosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl) -4-ethylphenyl) Pentaerythritol diphosphite and the like can be mentioned. These may be used alone or in admixture of two or more. Among the above, especially tris (2,4-di-tert-butylphenyl) phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert) -Butyl-4-methylphenyl) pentaerythritol diphosphite is preferred.

When the CF / PC pellet of the present invention contains a heat stabilizer, the blending amount thereof is usually 0.001 to 1 part by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is preferably 0.01 to 0.5 parts by mass. If the blending amount of the heat stabilizer is less than 0.001 part by mass, the effect as a heat stabilizer is insufficient, and if it exceeds 1 part by mass, the hydrolysis resistance may be deteriorated.

(Release agent)
Examples of the release agent include at least one compound selected from the group of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils. Can be mentioned.

Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acids. Here, the aliphatic carboxylic acid also includes an alicyclic carboxylic acid. Among these, the preferred aliphatic carboxylic acid is a monovalent or divalent carboxylic acid having 6 to 36 carbon atoms, and an aliphatic saturated monovalent carboxylic acid having 6 to 36 carbon atoms is more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, caproic acid, lauric acid, araquinic acid, bechenic acid, lignoceric acid, cerotic acid, melissic acid, tetraliacontanic acid, montanic acid, and adipine. Examples include acid and azelaic acid.

As the aliphatic carboxylic acid in the ester of the aliphatic carboxylic acid and the alcohol, the same one as the above-mentioned aliphatic carboxylic acid can be used. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, monohydric or polyhydric saturated alcohols having 30 or less carbon atoms are preferable, and aliphatic saturated monohydric alcohols or polyhydric alcohols having 30 or less carbon atoms are more preferable. Here, the aliphatic term also contains an alicyclic compound. Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol and the like. Can be mentioned.

The above ester compound may contain an aliphatic carboxylic acid and / or an alcohol as an impurity, or may be a mixture of a plurality of compounds.

Specific examples of esters of aliphatic carboxylic acid and alcohol include beeswax (a mixture containing myricyl palmitate as a main component), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, and glycerin monosteer. Examples thereof include rate, glycerin distearate, glycerin tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

Examples of the aliphatic hydrocarbon having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. Here, the aliphatic hydrocarbon also includes an alicyclic hydrocarbon. Moreover, these hydrocarbon compounds may be partially oxidized. Among these, paraffin wax, polyethylene wax or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable. The number average molecular weight of the aliphatic hydrocarbon is preferably 200 to 5000. These aliphatic hydrocarbons may be a single substance or a mixture of various constituents and molecular weights, as long as the main component is within the above range.

Examples of the polysiloxane-based silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

When the release agent is contained in the CF / PC pellet of the present invention, the blending amount thereof is usually 0.001 to 2 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is preferably 0.01 to 1 part by mass. If the amount of the release agent is less than 0.001 part by mass, the effect of mold release may not be sufficient, and if it exceeds 2 parts by mass, the hydrolysis resistance is lowered and the mold is contaminated during injection molding. There are problems such as.

(UV absorber)
Specific examples of the ultraviolet absorber include inorganic ultraviolet absorbers such as cerium oxide and zinc oxide, and organic ultraviolet absorbers such as benzotriazole compounds, benzophenone compounds and triazine compounds. Of these, organic UV absorbers are preferred. In particular, benzotriazole compounds, 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2,) 4-Dimethylphenyl) -1,3,5-triazine-2-yl] -5- (octyloxy) phenol, 2,2'-(1,4-phenylene) bis [4H-3,1-benzoxazine-4- On], [(4-methoxyphenyl) -methylene] -propanedioic acid-dimethyl ester is preferably at least one selected from the group.

Specific examples of the benzotriazole compound include a condensate with methyl-3- [3-tert-butyl-5- (2H-benzotriazole-2-yl) -4-hydroxyphenyl] propionate-polyethylene glycol. Specific examples of other benzotriazole compounds include 2-bis (5-methyl-2-hydroxyphenyl) benzotriazole, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) benzotriazole, and the like. 2- (3', 5'-di-tert-butyl-2'-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3-tert-butyl-5-methyl-2-hydroxyphenyl) -5-chloro Benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2- (3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy- 3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2,2'-methylene-bis [4- (1,1,3,3-tetramethylbutyl) -6- (2N) − Benzotriazole 2-yl) phenol] [methyl-3- [3-tert-butyl-5- (2H-benzotriazole-2-yl) -4-hydroxyphenyl] propionate-polyethylene glycol] condensate and the like. .. These may be used in combination of two or more.

Among the above, preferably 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl]- 2H-benzotriazole, 2- (4,6-diphenyl-1,3,5-triazine-2-yl) -5-[(hexyl) oxy] -phenol, 2- [4,6-bis (2,4) -Dimethylphenyl) -1,3,5-triazine-2-yl] -5- (octyloxy) phenol, 2,2'-methylene-bis [4- (1,1,3,3-tetramethylbutyl)- 6- (2N-benzotriazol 2-yl) phenol].

When the CF / PC pellet of the present invention contains an ultraviolet absorber, the blending amount thereof is usually 0.01 to 3 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is preferably 0.1 to 1 part by mass. If the blending amount of the ultraviolet absorber is less than 0.01 parts by mass, the effect of improving the weather resistance may be insufficient, and if it exceeds 3 parts by mass, problems such as mold devogit may occur.

(Dyeing pigment)
Examples of dyeing pigments include inorganic pigments, organic pigments, and organic dyes. Examples of inorganic pigments include sulfide pigments such as carbon black, cadmium red, and cadmium yellow; silicate pigments such as ultramarine blue; zinc flower, petal pattern, chromium oxide, titanium oxide, iron black, titanium yellow, and zinc-. Oxide pigments such as iron brown, titanium cobalt green, cobalt green, cobalt blue, copper-chromium black, copper-iron black; chrome acid pigments such as chrome yellow and molybdate orange; Russian pigments can be mentioned. Examples of organic pigments and organic dyes include phthalocyanine dyes such as copper phthalocyanine blue and copper phthalocyanine green; azo dyes such as nickel azo yellow; thioindigo, perinone, perylene, quinacridone, dioxazine, and isoindolinone. Condensed polycyclic dyes such as system and quinophthalone type; anthraquinone type, heterocyclic dyes, methyl type dyes and the like can be mentioned. These may be used in combination of two or more. Among these, carbon black, titanium oxide, cyanine-based, quinoline-based, anthraquinone-based, phthalocyanine-based compounds and the like are preferable from the viewpoint of thermal stability.

When the CF / PC pellet of the present invention contains a dye pigment, the blending amount thereof is usually 20 parts by mass or less, preferably 15 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. Parts or less, more preferably 12 parts by mass or less. If the blending amount of the dye pigment exceeds 20 parts by mass, the impact resistance may not be sufficient.

Carbon black also functions as an inorganic conductive substance. When carbon black is used as the inorganic conductive substance, as described above, the blending amount thereof can be set to be larger than the blending amount as the dye pigment.

(Flame retardants)
Flame retardants include halogenated bisphenol A polycarbonate, brominated bisphenol epoxy resin, brominated bisphenol phenoxy resin, brominated polystyrene and other halogen flame retardants, phosphoric acid ester flame retardants, diphenylsulfone-3,3'. Examples thereof include organic metal salt flame retardants such as dipotassium disulfonate, potassium diphenylsulfone-3-sulfonate, and potassium perfluorobutane sulfonate, and polyorganosiloxane flame retardants, but phosphoric acid ester flame retardants are particularly preferable. ..

Specific examples of the phosphoric acid ester flame retardant include triphenyl phosphate, resorcinol bis (dixylenyl phosphate), hydroquinone bis (dixylenyl phosphate), 4,4'-biphenol bis (dixylenyl phosphate), and bisphenol A. Examples thereof include bis (dixylenyl phosphate), resorcinol bis (diphenyl phosphate), hydroquinone bis (diphenyl phosphate), 4,4'-biphenol bis (diphenyl phosphate), bisphenol A bis (diphenyl phosphate) and the like. These may be used in combination of two or more. Among these, resorcinol bis (dixylenyl phosphate) and bisphenol A bis (diphenyl phosphate) are preferable.

When the CF / PC pellet of the present invention contains a flame retardant, the blending amount thereof is usually 1 to 30 parts by mass, preferably 3 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is ~ 25 parts by mass, more preferably 5 to 20 parts by mass. If the blending amount of the flame retardant is less than 1 part by mass, the flame retardancy may not be sufficient, and if it exceeds 30 parts by mass, the heat resistance may decrease.

(Dripping inhibitor)
Examples of the anti-dripping agent include fluorinated polyolefins such as polyfluoroethylene, and polytetrafluoroethylene having a fibril forming ability is particularly preferable. This shows a tendency to easily disperse in the polymer and to bond the polymers to each other to form a fibrous material. Polytetrafluoroethylene having the ability to form fibrils is classified into Type 3 according to the ASTM standard. As the polytetrafluoroethylene, not only the solid form but also the aqueous dispersion form can be used. Examples of polytetrafluoroethylene capable of forming fibrils include "Teflon (registered trademark) 6J" or "Teflon (registered trademark) 30J" from Mitsui Dupont Fluorochemicals, and "Polyflon (trade name)" from Daikin Industries, Ltd. It is commercially available as.

When the CF / PC pellet of the present invention contains a drip inhibitor, the blending amount thereof is usually 0.02 to 4 parts by mass with respect to 100 parts by mass of the polycarbonate resin (A) in the CF / PC pellet of the present invention. It is preferably 0.03 to 3 parts by mass. If the amount of the anti-dripping agent blended exceeds 5 parts by mass, the appearance of the molded product obtained by molding the obtained CF / PC pellets may be deteriorated.

[Manufacturing method of CF / PC pellets]
The above-mentioned method for producing CF / PC pellets of the present invention is not particularly limited, but preferably, the CF / PC pellets of the present invention have long fiber bundles of carbon fibers continuously formed in a molten resin bath of a polycarbonate resin. The long fiber bundle is impregnated with resin by widening the long fiber bundle in a band shape with an impregnation roll in the molten resin bath, and the resin-impregnated long fiber bundle is taken out from the molten resin bath. As a result, the process of manufacturing the carbon long fiber / polycarbonate resin composite material (hereinafter sometimes referred to as “CF / PC material”) and the process of cutting the manufactured CF / PC material to obtain the polycarbonate resin (A) and the carbon fiber. A method for producing CF / PC pellets, which comprises a step of obtaining CF / PC pellets containing (B), wherein the molten resin temperature is 290 to 340 ° C., and the long fiber bundles of the carbon fibers are epoxy / urethane. It is produced by a plutolution method according to the method for producing CF / PC pellets of the present invention, which is a continuous carbon long fiber bundle (b) treated with a system-based or polyester-based converging agent.

In the method for producing CF / PC pellets of the present invention, the molten resin of the polycarbonate resin may be composed of only the above-mentioned polycarbonate resin (A), and the polycarbonate resin (A) and other components, that is, , The above-mentioned flow improver (C), an inorganic conductive substance, another thermoplastic resin, and various additives may be included in the polycarbonate resin composition.

<Pllusion method>
First, a method for producing a CF / PC material and a CF / PC pellet by the plutolution method will be described with reference to FIGS. 1 to 5.

FIG. 1 is a schematic plan view showing an example of a CF / PC pellet manufacturing apparatus suitable for carrying out the present invention, and FIG. 2A is a schematic cross-sectional view showing a main part of the apparatus of FIG. (Vertical cross-sectional view of the resin impregnated cell and the preheating cell portion viewed from the direction of arrow II in FIG. 1), FIG. 2 (b) is a schematic view showing the arrangement of the impregnated roll and the guide roll, and is a schematic view of FIG. Corresponds to the figure seen from the direction of arrow B.
FIG. 3 is a schematic plan view showing another example of a CF / PC pellet manufacturing apparatus suitable for carrying out the present invention, and FIG. 4A is a schematic view showing a main part of the apparatus of FIG. A cross-sectional view (longitudinal cross-sectional view of the resin impregnated cell and the preheating cell portion as viewed from the direction of arrow IV in FIG. 3) and FIG. 4 (b) are schematic views showing the arrangement of the impregnated roll and the guide roll, and FIG. ) Corresponds to the figure seen from the direction of arrow B.
In FIGS. 1, 2 and 3 and 4, members having the same function are designated by the same reference numerals.

In FIGS. 1 and 2, 20 is an extruder (usually, a twin-screw extruder is used), has a hopper 21 for charging resin on the base end side, and the tip 20A side is the lower part of the resin impregnated cell 22. The molten resin 10 from the extruder 20 is extruded into the resin impregnated cell 22. As shown in FIG. 2A, a continuous long fiber bundle of carbon fibers (hereinafter, may be referred to as “CF roving”) 31 is preheated in a continuous tubular shape on the upper portion of the resin impregnated cell 22. A preheating cell 23 for this purpose is provided, and a CF roving winding body 30 for feeding the CF roving 31 is provided above the preheating cell 23. In FIG. 1, the CF roving winding body 30 and the preheating cell 23 are not shown.

Reference numeral 24 denotes a shaping die, and in the process of passing through the shaping die 24, the CF roving 31 impregnated with the molten resin 10 is formed into a predetermined cross-sectional shape. Reference numeral 25 denotes a water tank, and 26 is a pelletizer, which is provided with a take-up roll and a cutter.

The CF roving 31 continuously unwound from the CF roving winding body 30 is preheated to a predetermined temperature by a heater (not shown) in the preheating cell 23, and then passed through the resin impregnated cell 22 while the impregnated rolls 41 to 44. By widening the width in a band shape, the molten resin invades between the carbon fibers and is impregnated.
The resin-impregnated CF roving 32 pulled out by the take-up roll in the pelletizer 26 through the shaping die 24 is cooled in the water tank 25, and the CF / PC material 33 from the water tank 25 is brought to a predetermined length by the cutter in the pelletizer 26. It is cut into CF / PC pellets 34.

As shown in FIG. 2, an outlet side guide roll 40B for changing the traveling direction of the CF roving 31 from the vertical downward direction to the horizontal direction is provided in the resin impregnated cell 22, and the molten resin 10 above the guide roll 40B is provided. Four impregnated rolls 41, 42, 43, and 44 are provided inside (below the liquid level L of the molten resin 10) at intervals in the vertical direction. The guide rolls 40B and the impregnated rolls 41 to 44 are arranged side by side so that the roll axis direction is orthogonal to the traveling direction of the CF roving 31.

The guide roll 40B is provided at the same height as the outlet of the resin-impregnated CF roving 32 of the shaping die 24 in the molten resin 10.

In this CF / PC pellet manufacturing apparatus, the CF roving 31 that is fed vertically downward from the CF roving winding body 30 is preheated to about 100 to 300 ° C. in the preheating cell 23, and then enters the resin impregnated cell 22 and melts. In the resin 10, it comes into contact with the impregnated rolls 41 to 44 and is widened in a band shape. The molten resin 10 is impregnated between the carbon fibers of the CF roving 31 that has been widened and the fibers have been loosened, and the resin-impregnated CF roving 32 is shaped by the shaping die 24 via the guide roll 40B and picked up in the pelletizer 26. Taken by roll. The CF / PC material 33 obtained by cooling the resin-impregnated CF roving 32 in the water tank 25 is cut by a cutter in the pelletizer 26 to obtain CF / PC pellets 34.

In the CF / PC pellet manufacturing apparatus shown in FIGS. Guided by a guide roll 40A provided above the liquid level L of the molten resin 10 in the impregnated cell 22, it is sent into the molten resin 10 in the resin impregnated cell 22 and moves in the molten resin 10 in a substantially horizontal direction. The point is different from the CF / PC pellet manufacturing apparatus shown in FIGS. 1 and 2 in which the CF roving 31 moves vertically in the molten resin 10, and the other points have the same configuration.

As shown in FIG. 4, an inlet side guide roll 40A for changing the traveling direction of the CF roving 31 from a horizontal direction to an obliquely downward surface and an outlet side guide roll 40B are provided in the resin impregnated cell 22, and the guide rolls are provided. Four impregnated rolls 41, 42, 43, and 44 are provided below the liquid level L of the molten resin 10 between 40A and 40B at horizontal intervals. The guide rolls 40A and 40B and the impregnated rolls 41 to 44 are arranged side by side so that the roll axis direction thereof is orthogonal to the traveling direction of the CF roving 31.

The guide roll 40A is provided above the liquid level L of the molten resin 10 in the resin impregnated cell 22, and the guide roll 40B serves as an outlet of the resin impregnated CF roving 32 of the shaping die 24 in the molten resin 10. It is provided at a height position.

In this CF / PC pellet manufacturing apparatus, the CF roving 31 horizontally unwound from the CF roving winding body 30 is preheated to about 100 to 300 ° C. in the preheating cell 23, and then enters the resin impregnated cell 22 to guide the CF / PC pellets. The roll 40A goes diagonally downward and comes into contact with the impregnated rolls 41 to 44 in the molten resin 10 to be widened in a band shape. The molten resin 10 is impregnated between the carbon fibers of the CF roving 31 that has been widened and the fibers have been loosened, and the resin-impregnated CF roving 32 is shaped by the shaping die 24 via the guide roll 40B and picked up in the pelletizer 26. Taken by roll. The CF / PC material 33 obtained by cooling the resin-impregnated CF roving 32 in the water tank 25 is cut by a cutter in the pelletizer 26 to obtain CF / PC pellets 34.

It should be noted that FIGS. 1 to 4 show an example of a CF / PC pellet manufacturing apparatus suitable for carrying out the present invention, and the CF / PC pellet manufacturing apparatus used in the present invention is shown in FIGS. Not limited to what is shown.
For example, in FIGS. 1 to 4, the preheating cell 23 and the resin impregnated cell 22 have an I-shaped cross section so that the traveling direction of the CF roving 31 in the preheating cell 23 and the resin impregnated cell 22 is the vertical direction or the horizontal direction. The preheating cell 23A and the resin impregnated cell 22 are continuous in an L-shaped cross section so that the traveling direction of CF roving is horizontal on one side and the traveling direction of CF roving is vertical on the other side. May be provided. In this case, a guide roll for changing the traveling direction may be provided as needed.

Further, in FIGS. 2 and 4, the diameters a of the impregnated rolls 41 to 44 are all equal, and the diameters of the guide rolls 40A and 40B are slightly smaller than the diameters of the impregnated rolls 41 to 44, but are equal to the diameters of the impregnated rolls 41 to 44. It may be large or large. Further, the diameters a of the plurality of impregnated rolls do not have to be the same, but may be different. Also, the spacing c between adjacent impregnated rolls does not have to be the same, but may be different.

Although not particularly limited, the impregnated rolls 41 to 44 are usually provided in the molten resin 10 at equal intervals, and the interval c between adjacent impregnated rolls is 4 times or less the diameter a of the impregnated rolls, that is, It is 4a or less. Further, the guide roll 40A is provided at a position separated from the uppermost impregnation roll 41 by more than four times the diameter a of the impregnation roll, and the guide roll 40B has a diameter of the impregnation roll larger than that of the lowermost impregnation roll 44. It is provided at a position more than four times as large as a.

The CF roving 31 unwound from the CF roving winding body 30 is usually a continuous carbon long fiber bundle (b) in which about 1000 to 50,000 carbon fibers having a fiber diameter of about 3 to 10 μm are converged. The width b is 3 to 20 mm and the thickness is about 0.1 to 1 mm.

The diameter a (mm) of the impregnated roll is appropriately determined according to the width b (mm) of the CF roving, the size of the resin impregnated cell, and the like, but the impregnated roll is used for CF roving having a width b of 3 to 20 mm. The diameter a of the impregnated roll is 8 to 16 mm, particularly 10 to 14 mm, and the diameter a of the impregnated roll is preferably about 0.5 to 4 times the width b of the CF roving.

In FIGS. 2 and 4, four impregnated rolls 41 to 44 are provided, but the number of impregnated rolls may be two or more, and there is no particular limitation, but the number of impregnated rolls is usually 2 to 6. , Preferably 2-4.

Further, in FIGS. 2 and 4, the four impregnated rolls 41 to 44 are arranged side by side at a relatively small interval c, but as shown in FIGS. 5 (a) and 5 (b), the impregnated rolls 51 to 53 are arranged side by side. They may be arranged side by side at relatively large intervals.

<CF roving>
In the present invention, the above-mentioned continuous carbon long fiber bundle (b) is used as CF roving.
CF roving is used to achieve the carbon fiber (B) content of the CF / PC pellets of the present invention described above.

In FIGS. 1 to 4, CF roving is sent out using only one CF roving winding body, but when CF / PC pellets having a high carbon fiber content are produced, two or more CF roving windings are used. A rotating body may be used to run two or more CF rovings in parallel in the resin-impregnated cell.

<Melted resin (impregnated resin)>
In the present invention, the molten resin temperature (the temperature of the molten resin 10 in the resin impregnated cell 22 in FIGS. 1 to 4) is 290 to 340 ° C, preferably 300 to 330 ° C, and more preferably 310 to 330 ° C.
When the molten resin temperature is lower than the above lower limit, the viscosity of the molten polycarbonate resin is high, so that fiber breakage is likely to occur. If the temperature of the molten resin is higher than the above upper limit, there is no problem of fiber breakage, but the original physical properties of the polycarbonate resin are impaired due to thermal deterioration of the polycarbonate resin. The thermal deterioration of the polycarbonate resin can be grasped by the degree of decrease in the molecular weight of the polycarbonate resin.

As described above, the molten resin used for producing the CF / PC pellets of the present invention may be composed of only the above-mentioned polycarbonate resin (A), and the polycarbonate resin (A) and other components (that is, that is, It may consist of a polycarbonate resin composition containing the above-mentioned flow improver (C), an inorganic conductive substance, other thermoplastic resins, and various additives) in the above-mentioned suitable contents.

In the present invention, when the impregnating resin is composed of only the polycarbonate resin (A), the polycarbonate resin (A) is used, that is, the polycarbonate resin (A) is charged from the hopper 21 of the extruder 20 shown in FIGS. Then, CF / PC pellets can be produced by the above-mentioned extrusion method.

When a polycarbonate resin composition containing a flow improver (C), an inorganic conductive substance, other additives, etc. is used as the impregnating resin, the polycarbonate resin (A), the flow improver (C), and the inorganic conductivity are used. Using the sex substance, other additives, etc. in a predetermined ratio, that is, these are charged in a predetermined ratio from the hopper 21 of the extruder 20 of FIGS. / PC pellets can be produced.

In this case, the polycarbonate resin (A) and various components to be blended as needed are mixed in advance using various mixers such as a tumbler and a Henschel mixer, and then put into the hopper 21 of the extruder 20 for melting and kneading. Alternatively, each component may not be mixed in advance, or only a part of the components may be mixed in advance and supplied to an extruder using a feeder to be melt-kneaded.

<Resin-impregnated CF roving pick-up speed>
In the present invention, the take-up speed of the resin-impregnated CF roving, that is, in FIGS. 1 and 3, the take-up speed of the resin-impregnated CF roving 32 taken from the shaping die 24 by the take-up roll in the pelletizer 26 is preferably 1 to 12 kg /. It is hr, more preferably 3 to 11 kg / hr, and more preferably 5 to 10 kg / hr.

If this take-up speed is higher than the above upper limit, the tension applied to CF roving is too large, and fiber breakage tends to occur easily. Even if the take-up speed is low, there is no problem in terms of fiber breakage and fiber loss, but it is not preferable in terms of productivity.
More preferably, the take-up speed is slightly faster when the molten resin temperature is high and slightly slower when the molten resin temperature is low within the above range in correlation with the molten resin temperature, and can be appropriately adjusted. It is preferable from the viewpoint of preventing fiber breakage and productivity.

<Cutting CF / PC material>
The CF / PC material obtained by the above-mentioned plutolation method is cut with a pelletizer 26 to obtain CF / PC pellets 34.
In the present invention, the cutting length of the CF / PC pellet 34, that is, the length of the obtained CF / PC pellet is not particularly limited, but the mass average fiber length of the carbon fibers (B) in the pellet is 3000 to 10000 μm. In order to obtain (3 to 10 mm) CF / PC pellets, the cutting length is preferably 3 to 10 mm, particularly 4 to 9 mm, particularly 5 to 8 mm. The pellet thus obtained contains carbon fibers (B) having a fiber length substantially equal to the cutting length. If the cutting length is too short, the length of the carbon fibers (B) in the pellets will also be short, and the electromagnetic wave shielding property of the molded product obtained by using this will tend to decrease, and the fibers will fall out. There is. On the contrary, if the cutting length is too long, the moldability is impaired.

The diameter of the CF / PC pellet is determined by the width of the CF roving used, the amount of resin impregnation, and the like, but is usually about 2.5 to 3.5 mm.

[Electromagnetic wave shielding molded product]
By molding the CF / PC pellet of the present invention, a molded product having excellent electromagnetic wave shielding properties can be obtained. The molding method for CF / PC pellets of the present invention is not particularly limited, and molding methods generally used for thermoplastic resin compositions, such as injection molding, hollow molding, extrusion molding, sheet molding, and thermal molding. , Rotational molding, laminated molding and other molding methods can be applied. Among them, injection molding is common for manufacturing electromagnetic wave shielding molded products.

The CF / PC pellet of the present invention may be used alone for molding to form a molded product, but if necessary, it may be mixed with other components such as other resin pellets and used for molding. can.
Further, the CF / PC pellet of the present invention can also be multicolored composite molded with other resin pellets to obtain a composite molded product.

The field of application of the molded product obtained from the CF / PC pellet of the present invention is not particularly limited, but applications requiring electromagnetic wave shielding properties, such as OA equipment, AV equipment, measuring equipment, transportation equipment, communication equipment, and radar. Examples include housing applications such as devices, connectors, and packaging materials. In addition, there are also automobile applications that require high rigidity.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist of the present invention is not exceeded.

[Material used]
The raw material components used in the following Examples , Reference Examples and Comparative Examples are as shown in Table 1 below.

In Table 2 below, the types of carbon fiber converging agents are indicated by the following abbreviations.
E / U: Epoxy / Urethane-based convergence agent PES: Polyester-based convergence agent U: Urethane-based convergence agent PA: Polyamide-based convergence agent E: Epoxy-based convergence agent PER: Polyester-based convergence agent

[Evaluation method]
The pellets obtained in Examples, Reference Examples and Comparative Examples were evaluated by the following methods.

<Measurement of mass average fiber length of carbon fibers in pellets>
Approximately 1 gram of the obtained pellets are dissolved with methylene chloride, filtered, carbon fibers are isolated, and the isolated carbon fibers are spread on glass so as not to overlap as much as possible, and an optical microscope (Olympus "BX-50") is used. ”) Was observed at 12.5 times and photographed. The fiber lengths of the 3000 carbon fibers shown in the obtained photographs were measured and averaged to obtain the mass average fiber length (referred to as "pellet fiber length" in Table 2).
In the present invention, the mass average fiber length of the carbon fibers in the pellet is 3000 to 10000 μm (3 to 10 mm), preferably 4000 to 9000 μm (4 to 9 mm), and more preferably 5000 to 8000 μm (5 to 8 mm).

<Tensile / bending characteristics>
The obtained pellets are dried at 120 ° C. for 5 hours, and then molded using an injection molding machine (“J55-60H” manufactured by Japan Steel Works) at a cylinder set temperature of 280 to 300 ° C., a mold temperature of 100 ° C., an injection time of 2 seconds. Injection molding was performed under the condition of a cycle of 40 seconds, and an ISO multipurpose test piece (4 mm thick) was injection molded.
Using the obtained ISO test piece (thickness of 4 mm), the tensile strength (unit: MPa) and the tensile elastic modulus (unit: MPa) were measured in accordance with ISO standards 527-1 and ISO527-2.
The tensile strength is preferably 120 MPa or more, particularly 140 MPa or more. The tensile elastic modulus is preferably 14000 MPa or more, particularly 15500 MPa or more.
Further, in accordance with ISO178, the bending strength (unit: MPa) and the flexural modulus (unit: MPa) were measured at 23 ° C. using the above ISO test piece (thickness of 4 mm).
The bending strength is preferably 190 MPa or more, particularly 210 MPa or more. The flexural modulus is preferably 11000 MPa or more, particularly 12000 MPa or more.

<Charpy impact strength>
After drying the obtained pellets at 120 ° C. for 5 hours, a cylinder set temperature of 280 to 300 ° C., a mold temperature of 100 ° C., and a molding cycle of 45 seconds are used in an injection molding machine (“SG75MII” manufactured by Sumitomo Heavy Industries, Ltd.). A 4 mm thick impact resistance test piece based on ISO179-1, 2 was prepared, and the Charpy impact strength (kJ / m ² ) was measured at a temperature of 23 ° C. for the test piece without notch and with notch.
The notchless Charpy impact strength is preferably 25 kJ / m ² or more, particularly preferably 30 kJ / m ² . The notched Charpy impact strength is preferably 5 kJ / m ² or more, particularly 7 kJ / m ² or more.

<Electromagnetic wave shielding property>
After drying the obtained pellets at 120 ° C. for 5 hours, an injection molding machine (“J180AD” manufactured by Japan Steel Works, Ltd.) is used under the conditions of a cylinder set temperature of 320 ° C., a mold temperature of 120 ° C., and an injection speed of 1.6 seconds. Injection molding was performed to obtain a flat plate-shaped test piece having a thickness of 100 mm × 150 mm × 2 mm.
The electromagnetic wave shielding effect (unit: dB) at 600 MHz was measured for the obtained test piece with an electromagnetic wave shielding property measuring device compliant with the KEC (Kansai Electronics Industry Promotion Center) method.
The electromagnetic wave shielding effect is preferably −29 dB or less, particularly preferably −31 dB or less.

<Surface roughness>
The flat plate-shaped test piece obtained above was measured at 400 times using a surface roughness shape measuring machine (“Laser Microscope VK-X100” manufactured by KEYENCE, wavelength 658 nm red laser, output 0.95 mW, pulse width 1 ns). The surface roughness (arithmetic mean roughness: Ra) was measured by observing.
The surface roughness is preferably 1.0 μm or less, particularly preferably 0.5 μm or less.

<Measurement of mass average fiber length of carbon fibers in molded products>
A 5 mm × 5 mm sample was cut from the flat plate-shaped test piece obtained above, and this sample was dissolved with methylene chloride in the same manner as in the measurement of the mass average fiber length of carbon fibers in the pellets, filtered, and carbon. The fibers were isolated, the isolated carbon fibers were spread on the glass so as not to overlap as much as possible, and observed with an optical microscope (“BX-50” manufactured by Olympus) at a magnification of 12.5 times, and 3000 carbon fiber fibers were observed. The length was measured and added and averaged to determine the mass average fiber length (referred to as "molded fiber length" in Table 2).
The mass average fiber length of the carbon fibers in the molded product is preferably 400 μm or more, particularly preferably 500 μm or more.

[Examples 5 and 7, Reference Examples 1 to 4 and 6, Comparative Examples 1 to 4]
CF / PC pellets were produced by the plutolution method shown in FIGS. 1 and 2.
Of the components listed in Table 1 above, components other than CF roving were blended at the ratio of the resin composition blended shown in Table 2 below, and this was blended with a 40 mm single-screw extruder (VS40-32V manufactured by Tanabe Plastics Machinery Co., Ltd.). ) 20 was put into the hopper 21, melt-kneaded at a cylinder temperature of 280 ° C. and a screw rotation speed of 80 rpm, and extruded into a resin-impregnated cell 22 as an impregnated resin.
CF roving 31 was used with respect to this impregnated resin so as to have the ratio shown in Table 2. The CF roving 31 was preheated to 150 ° C. in the preheating cell 23.
The impregnated resin temperature was 330 ° C., the take-up speed of the resin-impregnated CF roving was 10 kg / hr, and the cutting length of the pellet was 6 mm (pellet length 6 mm). The diameter of this pellet was about 3 mm.
As the impregnating roll, one having a diameter of a = 12 mm was used. The CF roving contacts the impregnated roll with a width b = 8 mm. The thickness of CF roving is 0.3 mm.

[Comparative Examples 5 and 6]
Of the components listed in Table 1 above, components other than carbon fibers are blended at the ratio of the resin composition shown in Table 2 below, mixed uniformly with a tumbler mixer, and then the most upstream portion C1 to the maximum. Using a meshing type co-rotating twin-screw extruder "TEM37BS" manufactured by Toshiba Machine Co., Ltd., which has a cylinder configuration in the downstream part C12, the carbon fibers are fed to the extruder from the barrel in the upstream part of the extruder, and the ratio of carbon fibers is shown in Table 2. Side-feed the carbon fiber so that it becomes Obtained.

The following can be seen from Table 2.
CF / PC pellets of the present invention in which CF roving treated with an epoxy / urethane-based converging agent or a polyester-based converging agent is used so as to have a predetermined carbon fiber content, and the carbon fiber length in the pellet is within a predetermined range. The molded product obtained from the CF / PC pellets of Examples 5 and 7 corresponding to the above is excellent in strength, rigidity, and electromagnetic shielding property. In particular, in Examples 5 and 7 using the flow improver (C), since the carbon fibers are hard to be cut during molding, the length of the carbon fibers in the obtained molded product is maintained, and the strength, rigidity, and electromagnetic wave shielding are maintained. The properties are further improved, the surface roughness is small, and the appearance of the molded product is also excellent.
Further, according to the plutolution method, CF / PC pellets whose pellet length is substantially equal to the carbon fiber length in the pellet can be efficiently produced.

On the other hand, in Comparative Examples 1 to 4 using CF roving treated with a converging agent different from the epoxy / urethane-based or polyester-based converging agent such as epoxy-based, polyether-based, and polyamide-based, the plutolution method is also used. Even if pellets are produced, the rigidity and electromagnetic wave shielding properties are inferior.
Comparative Examples 5 and 6 use carbon short fibers, and as a result of the carbon fibers being cut during pellet production, the carbon fiber length in the pellet is short, and as a result, the carbon fiber length in the molded product is also short. It becomes short, and sufficient strength, rigidity, and electromagnetic wave shielding property cannot be obtained.

Since the molded product made of CF / PC pellets of the present invention has a high degree of electromagnetic shielding property and is excellent in strength and rigidity, various electronic and electrical equipment, precision equipment, OA equipment, transportation equipment such as automobiles, and various machines. It can be suitably used in the field of equipment, etc., and is particularly suitable for housings, bodies, housings, etc. of digital cameras or various mobile terminals, personal computers, etc., and for automobile applications requiring high rigidity, and its industrial use. The possibility is very high.

20 Extruder 21 Hopper 22 Resin impregnated cell 23 Preheating cell 24 Shaped die 25 Water tank 26 Pelletizer 30 CF roving winder 31 CF roving 32 Resin impregnated CF roving 33 CF / PC material 34 CF / PC pellets 40A, 40B Guide roll 41 , 42, 43, 44, 51, 52, 53 Impregnated roll

Claims (4)

A carbon fiber / polycarbonate resin composite pellet containing 10 to 100 parts by mass of carbon fiber (B) and 1 to 25 parts by mass of a flow improver (C) with respect to 100 parts by mass of the polycarbonate resin (A) to improve the flow. The agent (C) is a polycarbonate oligomer, and the carbon fibers (B) are made from a continuous carbon long fiber bundle (b) treated with an epoxy / urethane-based or polyester-based converging agent, and are contained in the pellets. A carbon fiber / polycarbonate resin composite pellet characterized in that the mass average fiber length of the carbon fiber (B) is in the range of 3000 to 10000 μm. The long fiber bundle of carbon fibers is continuously run in the molten resin bath of the polycarbonate resin, and the long fiber bundle is widened in a band shape with an impregnated roll in the molten resin bath. Is impregnated with resin, and the resin-impregnated long fiber bundle is taken from the molten resin bath to manufacture a carbon long fiber / polycarbonate resin composite material, and the manufactured carbon long fiber / polycarbonate resin composite material is cut to obtain polycarbonate. A method for producing a carbon fiber / polycarbonate resin composite pellet, which comprises a step of obtaining a carbon fiber / polycarbonate resin composite pellet containing the resin (A) and the carbon fiber (B).
The carbon fiber / polycarbonate resin composite pellet contains 10 to 100 parts by mass of carbon fiber (B) with respect to 100 parts by mass of the polycarbonate resin (A), and further contains 100 parts by mass of the flow improver (C) of the polycarbonate resin (A). Contains 1 to 25 parts by mass with respect to parts
The temperature of the molten resin in the molten resin bath is 290 to 340 ° C.
A method for producing a carbon fiber / polycarbonate resin composite pellet, wherein the long fiber bundle of the carbon fiber is a continuous long carbon fiber bundle (b) treated with an epoxy / urethane-based or polyester-based converging agent. The method for producing a carbon fiber / polycarbonate resin composite pellet according to claim 2 , wherein the pellet cutting length of the carbon long fiber / polycarbonate resin composite material is 3 to 10 mm. A molded product obtained by injection molding the carbon fiber / polycarbonate resin composite pellet according to claim 1.

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