JPH07310287A - Production of fiber-reinforced thermoplastic resin - Google Patents

Abstract

PURPOSE:To obtain a high-quality fiber-reinforced thermoplastic resin material, containing uniformly mixed reinforcing fibers and having good heat resistance, dimensional stability and creep characteristics by previously heat-treating a reinforcing fiber bundle at a high temperature and then coating the resultant fiber bundle with a thermoplastic resin under a specific high tension. CONSTITUTION:This method for producing a fiber-reinforced thermoplastic resin material is to previously heat-treat a reinforcing fiber bundle comprising acrylonitrile-based fibers, aramid fibers, rayon-based fibers and glass fibers, etc., at >=100 deg.C and the melting point of the thermoplastic resin or above, then coat the resultant heat-treated fiber bundle under a tension as high as 5-70% of the tensile strength at break with a molten thermoplastic resin under >=25kg/cm<2> pressure, mold the fiber bundle and subsequently cool the molded fiber bundle. The obtained fiber-reinforced thermoplastic resin material has a high grade and contains the reinforcing fibers uniformly dispersed in the whole molded material. The resin material is excellent in heat resistance, dimensional stability and creep and mechanical characteristics. A polyamide, polyethylene, polybutylene terephthalate, etc., can be exemplified as the thermoplastic resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses an injection molding machine or the like to
When molding a fiber-reinforced thermoplastic resin material, the generation of gas, which greatly affects the quality of the material, is suppressed, and the reinforcing fibers are highly impregnated with resin to fully exhibit their characteristics, and the entire molding material is reinforced. The present invention relates to a method for producing a fiber-reinforced thermoplastic resin material for obtaining a high-quality molding material in which fibers are uniformly dispersed and mixed.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a fiber-reinforced thermoplastic resin material, there is generally known a method in which a chopped strand obtained by cutting a fiber bundle into about 5 mm and a resin are kneaded and extruded by an extruder. However, according to this method, for example, in the case of aramid fiber which is an organic fiber, when it is cut into a short length, the fiber becomes cotton-like and becomes extremely bulky, which makes it difficult to bite into an extruder or a kneader, and is an inorganic fiber. Carbon fiber or glass fiber is the kneading process of the extruder,
There was a problem that the fiber-reinforced thermoplastic resin material obtained was crushed to a size of 0.5 mm or less by a high breaking force and the mechanical properties of the obtained fiber-reinforced thermoplastic resin material were deteriorated. Furthermore, in recent years, polyphenylene sulfide (PPS), polyether ether ketone (PE
EK), polyether sulfone (PES), etc. As reinforcement with heat-resistant thermoplastic resin becomes necessary, the sizing agent of the reinforcing fiber is thermally deteriorated during pellet formation by the extruder and during injection molding. There was also a problem that the dispersibility of was deteriorated. Further, when the molded product is used at high temperature, water and heat-deteriorated sizing agent accompanying the reinforcing fiber are gasified, and thus the heat resistance and mechanical properties of the obtained fiber-reinforced thermoplastic resin material are deteriorated. there were. In order to solve these drawbacks, JP-A-62-24035 and JP-A-57-90020 have been proposed. However, although it has an effect on the biting property and the crushing of the reinforcing fiber, it has not yet solved the problem that the water and the heat-deteriorated sizing agent accompanying the reinforcing fiber are gasified. Further, regarding the raw material to be used for the fiber-reinforced thermoplastic resin material reinforced with continuous fibers, it is also an important characteristic that the filament (single fiber) mixing ratio in the length direction is uniform. Is difficult to make. In addition, although it is disclosed in Japanese Patent Laid-Open No. 01-01591, it was also found that the resin impregnating property between fibers varies.

Further, in the fiber reinforced thermoplastic resin material reinforced by continuous long fibers described in the above-mentioned prior documents, for example, it is reinforced with an organic fiber having a higher elongation than a steel reinforcing material. Therefore, the dimensional stability and creep properties were inferior to those of steel reinforcing materials.

[0004]

The object of the present invention is to solve the problems of the prior art as described above. It has good biting property and dispersibility, and generates little gas due to thermal deterioration at the molding stage. It is an object to provide a material in which fibers are highly impregnated with a resin so as to sufficiently exhibit its properties, and reinforcing fibers are uniformly dispersed and mixed throughout the molding material. In addition, compared to fiber reinforced thermoplastic resin material with continuous long fibers, less gas is generated due to thermal deterioration in the molding stage, and the reinforcing fiber is highly impregnated with resin to fully exhibit its characteristics, and bubbles are not generated. It is another object of the present invention to provide a method for producing a material having good heat resistance, dimensional stability, creep properties, mechanical properties, etc., in which reinforcing fibers are uniformly dispersed and mixed in the entire molding material. In the method for producing a fiber-reinforced thermoplastic resin material, the present inventors heat-treat a reinforcing fiber bundle in advance to vaporize water or an oil agent adsorbed or attached to the reinforcing fiber, thereby forming a gas at the time of molding. In order to prevent the formation and its generation, and when the reinforcing fiber bundle is coated with the molten thermoplastic resin under high tension, pressure is applied to the resin to inject the thermoplastic resin with high viscosity into the reinforcing fiber bundle. And the resin-coated fiber bundle is re-molded at a temperature not lower than the melting temperature of the thermoplastic resin by using a molding nozzle to make the mixing ratio of the single fibers uniform in the length direction, and a molding material when this is used as a material. Alternatively, the inventors of the present invention have found that an injection-molded product or a press-molded product, which is cut and used as a raw material, is excellent in heat resistance, dimensional stability, creep properties and mechanical properties, and has reached the present invention.

[0005]

That is, according to the present invention, "(Claim 1) In a method of coating a reinforcing fiber bundle with a thermoplastic resin, the reinforcing fiber bundle is preliminarily heat-treated at a temperature of 100 ° C or more (preheating Step), and then a step of coating the reinforcing fiber bundle with the melted thermoplastic resin under a state in which the reinforcing fiber bundle is subjected to high tension of 5 to 70% of tensile breaking strength (coating step),
A method for producing a fiber-reinforced thermoplastic resin material, which comprises a subsequent cooling step (cooling step).

(Claim 2) The method for producing a fiber-reinforced thermoplastic resin material according to claim 1, wherein the preheating step is a step of heat-treating the reinforcing fiber bundle in advance at a temperature higher than the melting temperature of the thermoplastic resin.

(Claim 3) The coating step is a step of coating the reinforcing fiber bundle with a molten thermoplastic resin under a state where a high tension of 10 to 50% of the tensile breaking strength is applied to the reinforcing fiber bundle. A method for producing a fiber-reinforced thermoplastic resin material according to claim 1 or 2.

(Claim 4) The coating step is 25 kg / c
The method for producing a fiber-reinforced thermoplastic resin material according to claim 1, which is a step of coating the reinforcing fiber bundle with the molten thermoplastic resin under a pressure of m ² or more.

(Claim 5) In the method of coating a reinforcing fiber bundle with a thermoplastic resin, the reinforcing fiber bundle is previously coated with 1
A step of performing a heat treatment at a temperature of 00 ° C. or higher (preheating step), and then a thermoplastic resin melted in the reinforcing fiber bundle under a state where a high tension of 5 to 70% of tensile breaking strength is applied to the reinforcing fiber bundle. Coating step (coating step), a step of re-molding the resin-coated reinforcing fiber bundle with a molding nozzle at a temperature not lower than the melting temperature of the thermoplastic resin (re-molding step), followed by a cooling step (cooling step) The manufacturing method of the fiber reinforced thermoplastic resin material characterized by having these.

(Claim 6) The method for producing a fiber-reinforced thermoplastic resin material according to claim 5, wherein the preheating step is a step of heat-treating the reinforcing fiber bundle in advance at a temperature higher than the melting temperature of the thermoplastic resin.

(Claim 7) The coating step is a step of coating the reinforcing fiber bundle with a molten thermoplastic resin under a state where a high tension of 10 to 50% of tensile breaking strength is applied to the reinforcing fiber bundle. A method for producing a fiber-reinforced thermoplastic resin material according to claim 5 or 6.

(Claim 8) The coating step is 25 kg / c
The method for producing a fiber-reinforced thermoplastic resin material according to claim 5, which is a step of coating the reinforcing fiber bundle with the molten thermoplastic resin under a pressure of m ² or more. It is.

The reinforcing fibers used in the present invention include
Polyacrylonitrile-based, rayon-based, glass fiber, poly- (P-phenylene terephthalamide), which is a generic name for aramid fiber, poly- (m-phenylene terephthalamide)
Alternatively, one or a combination of two or more kinds of various fibers having a skeleton thereof, that is, a copolymer, an inorganic fiber, and an organic fiber can be used. In addition, in the combination of each fiber and resin,
The fiber may be subjected to an appropriate surface treatment such as an appropriate sizing treatment or a coupling agent treatment. As the thermoplastic resin used for coating, polyamide, polyethylene, polybutylene terephthalate, polyethylene terephthalate, polyarylate, polyether nitrile, polysulfone, polyarylene sulfide, polyether sulfone, polyetherimide, polyamideimide, polyacrylonitrile, polycarbonate , Rigid resins such as polyolefins, polyacetals and polystyrenes, and mixtures or copolymers thereof.

Further, these thermoplastic resins have various additives such as heat-resistant agents, light resistance improvers, UV deterioration inhibitors, antistatic agents, lubricants, release agents, and the like in order to improve their properties.
Colorants such as dyes and pigments, crystallization accelerators, flame retardants, and the like, and inorganic, organic, and metal powders such as calcium carbonate as the third component can also be easily added.

Next, the present invention will be described with reference to the drawings.

FIG. 1 shows an example of a manufacturing apparatus used for manufacturing the fiber-reinforced thermoplastic resin material of the present invention. A plurality of continuous reinforcing fiber bundles 1 are wound from the bobbin 2 via the guide guide 3 by the front tension control device 4 at least one required time, guided to the preheating heater 5, and subjected to heat treatment there. After vaporizing and vaporizing components that are harmful at the time of molding, the fiber bundle introduction side die 7 is passed through the guide 6
Is introduced into the polymer reservoir 8. The reinforcing fiber is melt-pressed by the screw 11, is covered with the molten thermoplastic resin extruded through the throat 10, and is guided to the outlet die 9
After passing through, after the excessive resin is squeezed by the molding nozzle 13 that is heated to the melting temperature of the thermoplastic resin or higher, the rear side tension control is performed via the guide guide roller 14 while being cooled by the cooling bath 15. While the tension is controlled by the device 16, it is taken up by the take-up roll 17 and wound on the winder 18 to obtain a long fiber reinforced thermoplastic resin material.

The fiber-reinforced thermoplastic resin material coated with the resin in the form of strands is cut into a desired length by a strand cutter or a pelletizer instead of being wound up by the winding machine 18, so that reinforcement equal to the cut length is obtained in the resin. It is also possible to obtain a pellet-shaped fiber-reinforced thermoplastic resin raw material in which the fibers for use are monofilaments or uniformly dispersed in a state close to the monofilaments.

The preheater 5 shown in FIG. 1 is attached to or adsorbed on the fiber, and can raise the temperature to a temperature at which water harmful to the molding, oil for treatment, adhesive and the like can be evaporated and vaporized. If so, the shape and type are not particularly limited, but it is desirable to use a non-contact type heater in order to minimize damage to the fiber bundle. or,
The heater is preferably arranged below the fiber bundle in order to prevent contamination by evaporative substances and gasification products rising from the fiber bundle. Further, in order to heat-treat a plurality of fiber bundles uniformly, it is desirable to provide a reflection plate and make the temperature between the fiber bundles uniform. The heat treatment temperature of the fiber bundle in the preheater 5 depends on the heat treatment time, but is higher than the temperature at which the substance adhering to or adsorbing to the fibers is vaporized or gasified, that is, 100 ° C. or higher if the adsorbed water is vaporized. If it is decomposed and removed, 230 ° C or higher is required. More preferably, it is set to a temperature higher than the melting temperature of the thermoplastic resin with which the fiber bundle is impregnated, so as to remove in advance the vaporized substances and gasified substances which are problems during molding. If this effect is to be obtained at a high take-up speed, the preheat treatment temperature is preferably higher than the melting temperature of the thermoplastic resin by 20 ° C. or more. However, if the temperature is set too high, not only the energy loss for heating is large, but also the fiber may be damaged by heat, resulting in a decrease in mechanical strength, which is not preferable. Therefore, for example, in the case of aramid fiber which is an organic fiber, the temperature is 150 ° C. or higher higher than the melting temperature of the thermoplastic resin, in the case of inorganic fiber, it is 200 ° C. or higher higher than the melting temperature of the inorganic fiber, and in the case of aramid fiber. The heat treatment is preferably performed at a temperature of 485 ° C. or lower at which the aramid fiber starts to decompose. Further, the processing time varies depending on the processing temperature, but if the processing time is 10 seconds or more, it is possible to suppress gas generation during molding.

By using the reinforcing fibers preheated in this manner, surprising facts have been discovered in addition to the effect of suppressing gas generation during molding. This is a phenomenon that is particularly noticeable in para-aramid fibers, but when a fiber bundle from which the adsorbed water content of the fiber bundle and the surface treatment agent, which is mainly an oil agent, has been removed by preheating, the interface between the fiber and the thermoplastic resin is used. This is a phenomenon that the adhesiveness is improved. That is, when the molten thermoplastic resin is adhered to the fiber bundle that is not preheated, the adhesion of the resin cannot catch up when the take-up speed exceeds a certain value, and resin adhesion unevenness occurs in the length direction of the fiber bundle. It was found that the preheated fiber bundles did not cause resin adhesion unevenness at a take-up speed of 1.5 times faster than that without preheat treatment, which is effective in improving productivity and quality. It was That is, the pre-heat treatment removes moisture or oil adhering to or adsorbed on the fiber surface, and
It is considered that the extreme surface layer portion of the fiber is oxidized, the wettability with the resin is improved, and the adhesiveness (adhesiveness) is improved.

The introduction die 7 in FIG. 1 is fixed to the die head 12 by bolts. The details of the die 7 are shown in FIG. 2, but it is desirable to provide a taper on the upper part, which is the entrance side of the fiber bundle, so that the fiber bundle can be passed through easily. The reinforcing fiber introduction hole 19 is preferably close to the cross-sectional area of the fiber bundle in order to facilitate pressurization in the polymer reservoir 8 and to prevent the molten thermoplastic resin from flowing out of the introduction hole 19 to the outside of the system. However, if they are too close to each other, the resistance between the fiber bundle and the introduction hole 19 increases, and it becomes difficult to pull out the fiber bundle. Therefore, the ratio of the introduction hole cross-sectional area to the fiber bundle cross-sectional area is preferably 1.02 times or more. On the other hand, if it is too large, the molten thermoplastic resin tends to flow out, making it difficult to pressurize the resin. Therefore, the ratio is preferably 1.70 times or less. The length of the introduction hole 19 is preferably long so as to improve the pressing force and prevent the molten thermoplastic resin from flowing out of the introduction hole 19 due to pressurization. From 3 to 20 mm
Is desirable.

The output die 9 is attached to the die head 12 by bolts.
It is fixed to. The details of the die 9 are shown in FIG. 3. From the viewpoint that the taper is provided on the upper side which is the entrance side of the fiber bundle and the molten thermoplastic resin adhered and impregnated to the reinforcing fiber bundle is drawn out while being squeezed to improve the resin impregnation. desirable.
In addition, the introduction hole 20 of the reinforcing fiber bundle which is coated and impregnated with the molten thermoplastic resin is used to flow unnecessary resin to the outside from the introduction hole 19 due to the pressure applied in the polymer reservoir 8 and the pressure of the molten thermoplastic resin. From the viewpoint of prevention, it is desirable that the cross-sectional area of the introduction hole 19 is equal to or larger than that. The length of the introduction hole 20 is determined from the viewpoints of pressurization in the polymer reservoir 8, prevention of outflow from the introduction hole 19 due to pressurization of the molten thermoplastic resin, and mobility of the resin-impregnated fiber. It is desirable that the length is less than or equal to

By supplying the molten thermoplastic resin from the screw 11 into the polymer reservoir 8 formed by the inlet die 7 and the outlet die 9, pressurization in the polymer reservoir 8 becomes possible and the reinforcing fiber While eliminating bubbles in the bundle,
It is possible to impregnate the reinforcing fibers with the molten thermoplastic resin. Since the viscosity of the molten thermoplastic resin is as high as 100,000 centipoise, when the applied pressure is low, the thermoplastic resin cannot enter the fiber bundle 1 and sufficient impregnability cannot be obtained. However, when the resin is pressed at a pressure of 25 kg / cm ² or more, preferably 50 kg / cm ² or more, the molten thermoplastic resin uniformly enters the reinforcing fiber bundle, and as a result, the reinforcing fibers are contained in the resin. It becomes a monofilament or a form in which it is uniformly dispersed in a state close to the monofilament, the adhesion between the fiber and the resin is enhanced, and a good fiber-reinforced thermoplastic resin material can be obtained. Also, the higher the pressure, the more quickly the molten thermoplastic resin can be impregnated into the inside of the fiber bundle. However, considering the rotational energy of the screw 11 for pressurization and the working accuracy of the dies 7 and 9,
It is desirable that the pressure is not more than kg / cm ² .

FIG. 4 shows details of the molding nozzle 13, but it is desirable to provide a taper on the entrance side of the reinforcing fiber bundle covered with the thermoplastic resin. By providing this taper, the thermoplastic resin is narrowed down, and this taper portion plays a role of a polymer reservoir for the resin removed by the narrowing down, so that the thermoplastic resin is uniformly coated and impregnated in the length direction. It becomes possible to do. The molding hole 21 has a target filament mixture ratio and cross-sectional shape,
That is, it can be formed in any shape such as a circle, a triangle, and a square. Furthermore, what is important in this molding nozzle 13 is to heat the fiber bundle to a temperature higher than the melting temperature of the thermoplastic resin impregnated with the coating. When the thermoplastic resin is squeezed at a temperature below the melting temperature of the thermoplastic resin, not only a high pulling tension is required, but also peeling occurs between the thermoplastic resin already impregnated with the reinforcing fiber and the reinforcing fiber. ,
This impairs impregnation and leaves an internal strain. Further, when the temperature of the nozzle 13 is significantly higher than the melting temperature of the thermoplastic resin, the viscosity of the thermoplastic resin decreases, so that not only the narrowing effect decreases but also the deterioration of the thermoplastic resin is accelerated. The mechanical properties of the resulting fiber-reinforced thermoplastic resin are deteriorated. The lead-out die 9 and the molding nozzle 13 can be freely separated, but it is desirable to make them as close as possible in order to prevent cooling and solidification of the reinforcing fiber bundle covered with the thermoplastic resin.

In the thermoplastic resin composition resin coating step of the present invention, the tensile strength of the reinforcing fiber bundle is in the range of 5 to 70% of the tensile breaking strength of the fiber bundle, preferably 10 to 10.
It is desirable to set the high tension within the range of 50%. The reason is to reduce the elongation of the material reinforced by the thermoplastic resin and reinforced, and improve the dimensional stability and the creep property. That is, in the molten thermoplastic resin coating step, if the tension of the reinforcing fiber bundle is too low, the alignability of the single fibers constituting the fiber bundle is reduced, causing stress concentration and residual strain at specific locations, and reinforcing fibers. It will not be possible to fully develop the properties such as the original high strength, low elongation, and low creep property of the fiber-reinforced composite material. Therefore, in order to solve these problems, it is desirable to set the tensile strength to at least 5% of the breaking strength of the fiber bundle to be used, preferably 10 to 50%. Further, if the tension of the fiber bundle exceeds 70% of the breaking strength, partial cutting of the single fiber occurs particularly in the introduction side die 7, the discharge side die 9 and the molding nozzle 13, which is not preferable.

Particularly, an organic fiber having a breaking elongation of more than 2.0% or other fiber material is used as a resin-reinforcing fiber material, or is used in a state in which a fiber bundle is twisted to a low degree according to the purpose of use. In this case, it is desirable to impregnate the fiber bundle with the thermoplastic resin under the condition that high tension is applied so that the elongation at break of the fiber material to be used is at least 10% or more. It has been found that the fiber-reinforced thermoplastic resin material thus obtained has an elongation which is lower than the elongation at break which the fiber material itself has depending on the conditions, and therefore the dimensional stability and the creep property are also improved. This phenomenon suggests that it is possible to bring organic fibers, which are inferior in elongation and creep properties in comparison with steel fibers, closer to steel fiber reinforcement materials, and are lightweight as a steel substitute material, This shows that it is possible to provide a material having a low elongation and a low creep property and good dimensional stability.

The manufacturing apparatus and the manufacturing process shown in FIGS. 1, 2, 3, and 4 are merely examples for manufacturing the material of the present invention, and the apparatus and the process which can exhibit the same effects as those described above are provided. If so, there is no limitation.

[0027]

The characteristics of the fiber reinforced thermoplastic resin material produced by the production method of the present invention are as follows. (1) The material produced by the production method of the present invention has good impregnating property of the thermoplastic resin into the reinforcing fiber, has a small amount of voids in the material, and has interfacial adhesion between the resin and the fiber. High and good. (2) According to the manufacturing method of the present invention, it is possible to provide a fiber-reinforced material having various cross-sectional shapes according to the purpose of use. (3) The fiber-reinforced thermoplastic resin material produced by the production method of the present invention has low elongation and low creep properties, and is excellent in dimensional stability.

The present invention will be specifically described below with reference to examples. The content of reinforcing fiber (% by weight), the wire diameter, the breaking strength, the breaking elongation, the presence or absence of gas generation, the creep characteristics, and the resin impregnation property into the fiber bundle were evaluated for the fiber-reinforced thermoplastic resin material. Was carried out according to the following method. <Content of Reinforcing Fiber> Content (% by weight) = (weight of reinforcing fiber / weight of fiber reinforced thermoplastic resin material) x 100 <Measurement of wire diameter> For a fiber reinforced thermoplastic resin material sample having a length of 50 cm, Load 1/20 of material and 10 cm
The wire diameter is measured at 5 points for each interval, and the average value is shown. <Strength at break and elongation at break> INT made by INTESCO Corporation
JIS standard using ESCO (Model 2005),
Measured according to L1013. However, the chuck is for steel fiber. <Evaluation of gas generation in manufacturing process> Using temperature-increasing gas chromatography with a gas chromatographic model G80 manufactured by Yanagimoto Seisakusho Co., Ltd., measurement was performed on three samples of reinforcing fiber, thermoplastic resin, and fiber-reinforced thermoplastic resin material that had not been surface treated However, if the decomposition peak of the fiber-reinforced thermoplastic resin material consists of the decomposition peak of the reinforcing fiber that is not surface-treated and the decomposition peak of the thermoplastic resin, no gas is generated, and the decomposition fiber of the reinforcing fiber that is not surface-treated is decomposed. Gas was generated when a decomposition peak other than the peak and the decomposition peak of the thermoplastic resin was observed in comparison with the decomposition peak of the fiber-reinforced thermoplastic resin material.

The measurement conditions at this time are: Carrier Gas: He Inject temperature: melting point + 15 ° C. (for PPS: 30
0 ° C.) Column: left at 100 ° C. for 10 minutes, heated to 300 ° C. at a rate of 10 ° C./minute, and then left for 10 minutes. <Evaluation of Creep Properties> A load corresponding to 30% of the breaking strength of the fiber reinforced thermoplastic resin material was applied at room temperature, and the creep rate after leaving for 10 days was measured and used as a scale of the creep properties. <Evaluation of Impregnation of Resin into Fiber Bundle> The cross section of the fiber-reinforced thermoplastic resin material was observed with an electron microscope (or optical microscope) to evaluate the dispersibility of the fiber in the resin material.

X: The whole reinforcing fibers are bundled in a bundle. Δ: The whole reinforcing fiber is not bundled, but the reinforcing fibers are divided into several parts and bundled. ○: Of the reinforcing fibers About 50% or more dispersed in single fiber

[0031]

[Example 1] Four para-aramid fibers (Technora, Teijin Ltd.) consisting of 1500 denier / 1000 filaments were pre-twisted at 40 t / m on one side, and a load of 7% of tensile breaking strength was applied to them. After passing through a preheater heated to 350 ° C. for 15 seconds, it is introduced into a polymer reservoir through an introduction hole having an inner diameter of 0.9 mm and a length of 20 mm and extruded from a screw at 290 ° C. The molten thermoplastic resin of 1. was impregnated into the fiber (pressurized 30 kg / cm ² ), and further, molding was performed with a molding nozzle having an inner diameter of 1.0 mm and a length of 5 mm heated to 290 ° C., followed by cooling to contain reinforcing fiber. A fiber reinforced thermoplastic resin material having a rate of 68% was obtained. The take-up speed at this time was 10 m / min. Nylon 66 (Asahi Kasei Co., Ltd.) was used as the thermoplastic resin for coating. With respect to the fiber-reinforced thermoplastic resin material obtained, the breaking strength, breaking elongation and creep rate were measured and the results are shown in Tables 1 and 2.

[0032]

Example 2 A fiber-reinforced thermoplastic resin material was obtained in the same manner as in Example 1 except that a tension corresponding to 15% of tensile breaking strength was applied. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0033]

Example 3 A fiber-reinforced thermoplastic resin material was obtained in the same manner as in Example 1 except that a tension corresponding to 30% of tensile breaking strength was applied. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0034]

Example 4 A fiber-reinforced thermoplastic resin material was obtained in the same manner as in Example 1 except that a tension corresponding to 45% of tensile breaking strength was applied. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0035]

Example 5 A fiber-reinforced thermoplastic resin material was obtained in the same manner as in Example 1 except that a tension corresponding to 65% of tensile breaking strength was applied. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0036]

[Embodiment 6] Embodiment 5 except that a molding nozzle is not used.
The same procedure as described above was performed to obtain a fiber-reinforced thermoplastic resin material.
The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0037]

[Embodiment 7] The applied pressure during resin coating is 60 kg / c.
A fiber reinforced thermoplastic resin material was obtained in the same manner as in Example 6 except that m ² was changed. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0038]

[Example 8] A fiber-reinforced thermoplastic resin was prepared in the same manner as in Example 1 except that tension equivalent to 15% of tensile strength at break was applied, preheat treatment temperature was 120 ° C, and the coating resin was changed to nylon 6. Got the material. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0039]

[Example 9] A fiber-reinforced thermoplastic resin material was obtained in the same manner as in Example 8 except that the preheat treatment temperature was changed to 180 ° C. About this, the characteristics were evaluated in the same manner as in Example 1,
The results are shown in Tables 1 and 2.

[0040]

Example 10 A fiber reinforced thermoplastic resin material was obtained in the same manner as in Example 8 except that the preheat treatment temperature was changed to 230 ° C. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0041]

[Example 11] A fiber reinforced thermoplastic resin material was obtained in the same manner as in Example 8 except that the preheat treatment temperature was changed to 280 ° C. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0042]

Example 12 A fiber reinforced thermoplastic resin material was obtained in the same manner as in Example 8 except that the preheat treatment temperature was changed to 350 ° C. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0043]

Example 13 A fiber reinforced thermoplastic resin material was obtained in the same manner as in Example 11 except that the molding nozzle was not used. The properties of this were evaluated in the same manner as in Example 1, and the results are shown in Tables 1 and 2.

[0044]

[Comparative Example 1] A target sample was obtained in the same manner as in Example 1 except that a tension corresponding to 3% of the tensile breaking strength was applied and the applied pressure to the resin was 20 kg / cm ^2. It was The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0045]

Comparative Example 2 A target sample was obtained in the same manner as in Example 1 except that a tension corresponding to 3% of the tensile breaking strength was applied. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0046]

[Comparative Example 3] In Example 1, the tensile breaking strength was 80%.
A target sample was obtained in the same manner except that the tension corresponding to was applied and the applied pressure to the resin was set to 20 kg / cm ² . The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0047]

Comparative Example 4 A target sample was obtained in the same manner as in Example 1 except that a tension corresponding to 80% of tensile breaking strength was applied and a molding nozzle was not used. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0048]

Comparative Example 5 A target sample was obtained in the same manner as in Example 8 except that no heat treatment was performed. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0049]

COMPARATIVE EXAMPLE 6 A target sample was obtained in the same manner as in Example 8 except that the heat treatment temperature was 80 ° C. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0050]

Comparative Example 7 In Example 8, the heat treatment temperature was 500 ° C.
A target sample was obtained in the same manner except that the above procedure was performed. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0051]

[Comparative Example 8] In Example 8, the heat treatment temperature was 500 ° C.
In the same manner as described above except that the molding nozzle was not used to obtain a target sample. The physical properties of this sample were evaluated in the same manner as in Example 1, and the results are shown in Tables 3 and 4.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

[Table 4]

From Table 1, Table 2, Table 3 and Table 4, it is clear that the fiber reinforced thermoplastic resin materials of the present invention all have superior impregnability as compared with Comparative Examples.

[Brief description of drawings]

FIG. 1 is a schematic view of a fiber-reinforced thermoplastic resin material manufacturing apparatus.

FIG. 2 is a side sectional view of an introduction die.

FIG. 3 is a side sectional view of a lead-out die.

FIG. 4 is a side sectional view of a molding nozzle.

[Explanation of symbols]

 1 Reinforcing Fiber 2 Bobbin 3 Guide Guide 4 Front Tension Control Device 5 Preheater Heater 6 Guide Guide 7 Introduction Side Die 8 Resin Reservoir 9 Derivation Side Die 10 Throat 11 Screw 12 Die Head 13 Forming Nozzle 14 Guide Guide Roller 15 Cooling Bath 16 Rear Side Tension control device 17 Pulling roll 18 Winding machine 19 Reinforcing fiber introduction hole 20 Reinforcing fiber outlet hole 21 Forming hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadahiko Takada 3-4-1 Mihara, Ibaraki City, Osaka Prefecture Teijin Limited Osaka Research Center

Claims (8)

[Claims] 1. A method of coating a reinforcing fiber bundle with a thermoplastic resin, wherein the reinforcing fiber bundle is preliminarily heat-treated at a temperature of 100 ° C. or higher (preheating step), and then the reinforcing fiber bundle is stretched. A step (coating step) of coating the reinforcing fiber bundle with the molten thermoplastic resin under a high tension of 5 to 70% of breaking strength, followed by cooling (cooling step)
A method for producing a fiber-reinforced thermoplastic resin material, comprising: 2. The method for producing a fiber-reinforced thermoplastic resin material according to claim 1, wherein the preheating step is a step of preliminarily heat-treating the reinforcing fiber bundle at a temperature higher than the melting temperature of the thermoplastic resin. 3. The covering step is a step of covering the reinforcing fiber bundle with a molten thermoplastic resin under a state where a high tension of 10 to 50% of tensile breaking strength is applied to the reinforcing fiber bundle. 1. The method for producing a fiber-reinforced thermoplastic resin material according to 1 or 2. 4. The fiber-reinforced thermoplastic according to claim 1, wherein the coating step is a step of coating the reinforcing fiber bundle with the molten thermoplastic resin under a pressure of 25 kg / cm ² or more. Method for manufacturing resin material. 5. A method of coating a reinforcing fiber bundle with a thermoplastic resin, wherein the reinforcing fiber bundle is heat-treated at a temperature of 100 ° C. or higher in advance (preheating step), and then the reinforcing fiber bundle is stretched. A step of coating the reinforcing fiber bundle with the molten thermoplastic resin under a high tension of 5 to 70% of breaking strength (coating step), a molding nozzle at a temperature not lower than the melting temperature of the thermoplastic resin. The method for producing a fiber-reinforced thermoplastic resin material, comprising: a step of re-molding the resin-coated reinforcing fiber bundle (re-molding step) and a subsequent cooling step (cooling step). 6. The method for producing a fiber-reinforced thermoplastic resin material according to claim 5, wherein the preheating step is a step of previously heat-treating the reinforcing fiber bundle at a temperature higher than the melting temperature of the thermoplastic resin. 7. The coating step is a step of coating the reinforcing fiber bundle with a melted thermoplastic resin under a state where a high tension of 10 to 50% of tensile breaking strength is applied to the reinforcing fiber bundle. 5. The method for producing a fiber-reinforced thermoplastic resin material according to 5 or 6. 8. The fiber-reinforced thermoplastic according to claim 5, wherein the coating step is a step of coating the reinforcing fiber bundle with the molten thermoplastic resin under a pressure of 25 kg / cm ² or more. Method for manufacturing resin material.