JP5598931B2 - Fiber reinforced resin substrate, method for producing resin molded body, and resin processing machine for implementing the method - Google Patents

Description

  The present invention relates to a fiber reinforced resin base material composed of a reinforced fiber and a thermoplastic resin, a method for producing a resin molded body, and a resin processing machine for the implementation thereof, and in particular, a thermoplastic resin using a T-die. The present invention relates to a resin base material impregnated in a reinforcing fiber bundle or a reinforcing fiber fabric, a method for producing a resin molded body, and a resin processing machine for implementing the method.

  Carbon fiber reinforced resin is lightweight and has high strength, and is used for golf club shafts, fishing rods, tennis rackets, building materials, aircraft, etc. However, application to general automobile parts where mass productivity is important has not progressed. However, the development of technology for reducing the weight of automobiles has become an important issue due to changes in the social situation where environmental impact reduction is required, and its application to general automobile parts where carbon fiber reinforced resin may be used in large quantities is drawing attention. ing.

  Until now, many commercialized carbon fiber reinforced resins made of reinforced fibers and resins have used a thermosetting resin such as an epoxy resin as a matrix resin, and few have used a thermoplastic resin. This is because it is not easy to impregnate the carbon fiber bundle with the thermoplastic resin, but considering the advantages such as ease of handling, high productivity, and expandability of the application, the matrix is thermoplastic resin. Attempts have been made to develop a carbon fiber reinforced resin or molded product thereof.

  For example, Patent Document 1 discloses a method for manufacturing a resin prepreg, which includes pressurizing and impregnating a matrix resin between fibers of a fiber sheet, and sewing a sewing thread in a direction crossing the fiber orientation with respect to the fiber sheet. There has been proposed a method for producing a resin prepreg characterized by performing a suturing process and a fiber opening process for removing a drug applied to fibers and opening a fiber bundle.

  In Patent Document 2, a reduced-pressure seal part, a temperature-controllable connection part, and a die in which a molten resin is stored are connected in series, and a strip-shaped reinforcing fiber bundle made of a plurality of continuous reinforcing fibers is introduced from an inlet at the end of the seal part. There has been proposed a method for manufacturing a sheet-like pre-leg that is inserted through a molten resin in a connecting portion and a die and pulled from the end of the die. According to this manufacturing method, the resin is uniformly and satisfactorily impregnated and the impregnation time is short. In this manufacturing method, the connecting portion has a heating zone on the die side and a cooling zone on the seal portion side, and the heating zone has a temperature gradient from the temperature of the cooling zone to the temperature approaching the die temperature. Therefore, it is said that the outflow length of the molten resin in the die to the connecting portion can be kept short.

  In Patent Document 3, a fiber bundle composed of carbon fiber monofilaments having an average diameter of 5 to 10 μm is contained in an impregnation bath in which an impregnation roller is connected and a thermoplastic resin having a viscosity of 100 to 1000 Pa · s is stored. There has been proposed a method for producing a thermoplastic resin-impregnated strand that is inserted so as to be sewed and pulled by being loaded with a predetermined tension. In this production method, the tension applied to the fiber bundle is set within a predetermined range determined from the viscosity of the thermoplastic resin through which the fiber bundle is inserted, the diameter of the impregnation roller, the conveyance speed, and the strength of the fiber bundle. The resin impregnation rate can be increased.

  In Patent Document 4, after arranging the transmittance adjusting member in the cavity of one mold having the matrix resin injection port, the reinforcing fiber base material is arranged, and the other mold is fitted, A molding method for a composite material has been proposed in which a matrix resin is pressed and impregnated into a reinforcing fiber base material through a transmittance adjusting member in a cavity from the matrix resin injection port, and a composite material is molded by heating and pressurizing. ing.

JP 2008-179808 JP JP 2012-16857 A JP 2011-245754 A JP 11-348059 A

  In the production of fiber reinforced resin using a thermoplastic resin as a matrix, in order to increase productivity and economy, the pellets of thermoplastic resin are melted and impregnated into reinforced fibers, cooled and solidified to form a resin molded product. A series of manufacturing methods is preferred. From such a viewpoint, a reinforcing fiber bundle is formed in a molten resin bath as described in Patent Documents 2 and 3, rather than a method of impregnating a fiber sheet with resin using a fiber sheet and a resin sheet as described in Patent Document 1. A method of inserting and impregnating a resin is preferable, and a method of directly molding a composite material by filling and pressing a molten resin into a reinforcing fiber base placed in a mold as described in Patent Document 4 is more preferable. preferable.

  However, the method described in Patent Document 2 or 3 is limited to the production of resin base materials such as strands and prepregs in which reinforcing fibers are continuous in one direction, and there is a problem that the production of a resin molded body must be performed separately. . The method described in Patent Document 4 must be filled with a molten resin having a high viscosity via a transmittance adjusting member, and there are problems in selecting a transmittance adjusting member and production efficiency. Further, the methods described in Patent Documents 2 to 4 also have a problem that a vacuum mechanism is essential for impregnating the resin.

  In view of such conventional problems, the present invention can effectively impregnate a reinforcing fiber with a resin, and has a high productivity and economical fiber-reinforced resin base material and a method for producing a resin molded body And it aims at providing the resin processing machine for the implementation. And it aims at providing the resin base material which can be used conveniently especially for carbon fiber etc. with high heat conductivity of a reinforced fiber, the manufacturing method of a resin molding, and the resin processing machine for the implementation .

The method for producing a fiber-reinforced resin base material according to the present invention is a method for producing a fiber-reinforced resin base material composed of reinforcing fibers and a thermoplastic resin, and is a reinforcing fiber bundle placed in a planar shape. Alternatively, the molten fiber bundle or the reinforcing fiber fabric is impregnated into the upper surface of the reinforcing fiber fabric while supplying the molten thermoplastic resin from the T die so that a dynamic pressure of 0.01 to 5 MPa is applied as a gauge pressure. It is carried out by cooling the impregnated reinforcing fiber bundle or the reinforcing fiber fabric.

  In the above invention, the molten resin is preferably supplied in a state where the surface temperature of the reinforcing fiber bundle or the reinforcing fiber fabric is in the temperature range of −100 ° C. to + 50 ° C. of the discharge temperature of the resin to be supplied.

  Further, the molten resin can be supplied in a layered manner or partially overlaid, and the resin discharge amount can be partially changed by changing the discharge pressure and moving speed of the T die. .

  In the above invention, the reinforcing fiber bundle or the reinforcing fiber fabric may be made of carbon fiber.

Further, the method for producing a fiber reinforced resin base material according to the present invention includes a molten thermoplastic resin on a top surface of a reinforcing fiber bundle or a reinforcing fiber fabric placed on a base having heating and cooling means from a T die. A reinforcing fiber bundle or a reinforcing fiber fabric is impregnated while supplying a dynamic pressure of 0.01 to 5 MPa at a gauge pressure, and the reinforcing fiber bundle or the reinforcing fiber fabric impregnated with the thermoplastic resin is used as the base. It is carried out by cooling after pressurizing between rollers.

The method for producing a fiber-reinforced resin molded body according to the present invention includes a molten thermoplastic resin on the upper surface of a reinforcing fiber bundle or a reinforcing fiber fabric placed on a lower mold in an upper and lower mold having heating and cooling means. Is impregnated into a reinforcing fiber bundle or a reinforcing fiber fabric while supplying a dynamic pressure of 0.01 to 5 MPa with a gauge pressure from a T die, and then the upper mold is closed to the lower mold and the thermoplastic resin It is carried out by pressurizing and cooling a reinforcing fiber bundle or reinforcing fiber fabric impregnated with.

  The fiber reinforced resin base material and resin molded body have a T die, and a resin processing machine having a heating means for heating a surface portion of a fiber bundle or a reinforced fiber fabric to which a molten resin is supplied to a predetermined temperature Thus, it can be suitably manufactured.

  According to the present invention, it is possible to effectively impregnate a reinforcing fiber with a thermoplastic resin, and it is possible to produce a fiber-reinforced resin base material and resin molded body with high productivity and economy. In addition, according to the present invention, weld lines are unlikely to occur, and there is no problem like the resin transfer molding method (RTM).

It is explanatory drawing of the method of manufacturing the fiber reinforced resin base material which concerns on this invention. It is explanatory drawing which shows the example in the case of performing so that resin to supply may be partially overlaid on the upper surface of a reinforced fiber bundle or a reinforced fiber fabric. It is explanatory drawing of the method of manufacturing the fiber reinforced resin molding which concerns on this invention.

Hereinafter, modes for carrying out the present invention will be described. The method for producing a fiber-reinforced resin base material according to the present invention is a method for producing a fiber-reinforced resin base material composed of reinforcing fibers and a thermoplastic resin, and is a reinforcing fiber bundle placed in a planar shape. Alternatively, the molten fiber bundle or the reinforcing fiber fabric is impregnated into the upper surface of the reinforcing fiber fabric while supplying the molten thermoplastic resin from the T die so that a dynamic pressure of 0.01 to 5 MPa is applied as a gauge pressure. It is carried out by cooling the impregnated reinforcing fiber bundle or the reinforcing fiber fabric. That is, in this manufacturing method, a molten thermoplastic resin is supplied from the T die so that a dynamic pressure of 0.01 to 5 MPa is applied from the T die to the upper surface of the reinforcing fiber bundle or the reinforcing fiber fabric placed in a plane. Thus, the reinforcing fiber bundle or the reinforcing fiber fabric is impregnated with the thermoplastic resin.

  The reinforcing fiber can include various fibers such as carbon fiber, ceramic fiber, and glass fiber, and is not particularly limited. However, the present invention can be suitably used for carbon fibers having a high thermal conductivity that rapidly takes away the heat when the molten thermoplastic resin comes into contact, making it difficult to impregnate the thermoplastic resin.

  When the reinforcing fibers are carbon fibers, they are generally processed into 1000 (1k) or more, for example, 1k to 24k, single strands having an outer diameter of 4 to 10 μm, which are threaded (strands). The strand is arranged into warp and weft and processed into a reinforced fiber fabric, or cut into a predetermined length and processed into chopped fiber or the like.

  In the present invention, the reinforcing fiber bundle refers to a state in which a plurality of strands are arranged in a plane, a state in which the strands are opened and widened, or a mat-like shape in which fibers are laminated discontinuously. .

A reinforced fiber bundle or reinforced fiber fabric in which single fibers made of carbon fibers having an outer diameter of the order of microns are bundled, and a large number of gaps of μm or less are formed between the single fibers, and impregnation with a thermoplastic resin having a high viscosity. Making it difficult. However, the present invention utilizes the property that the viscosity of the molten resin decreases logarithmically with the magnitude of the shear rate. That is, in the present invention, the upper surface of the reinforcing fiber bundle or the reinforcing fiber fabric is supplied so that a dynamic pressure of 0.01 to 5 MPa is applied as a gauge pressure, and a shearing force acts on the molten resin by the reinforcing fibers such as carbon fibers. The molten resin is supplied as follows. For this reason, according to the present invention, the reinforcing fiber bundle or the reinforcing fiber fabric can be effectively impregnated with the thermoplastic resin.

  In the present invention, the thermoplastic resin is not particularly limited. For example, various resins such as polyethylene resin, polypropylene resin, polyethylene terephthalate resin, polystyrene resin, and polycarbonate resin, or various grades of thermoplastic resins can be used.

  The manufacturing method of the resin base material which concerns on this invention can be implemented by the method shown, for example in FIG. In this manufacturing method, as shown in FIG. 1, a reinforcing fiber bundle 2 (or reinforcing fiber fabric 2) is placed in a flat shape on a base 1, and a molten resin 3 made of a thermoplastic resin is formed on the upper surface of the reinforcing fiber bundle 2. Is supplied from the resin processing machine 10. The base 1 has heating / cooling means, and the resin processing machine 10 has a T die 12. The T-die is suitable for supplying the molten resin so that dynamic pressure is applied to the upper surface of the reinforcing fiber bundle or the reinforcing fiber fabric. Further, the T die has an advantage that the capacity of the resin to be supplied or the thickness of the resin supplied to the upper surface of the reinforcing fiber bundle or the reinforcing fiber fabric can be suitably controlled.

  In this manufacturing method, the reinforcing fiber bundle 2 is heated by the heating means 5 so that the reinforcing fiber bundle 2 can be supplied with the molten resin 3 at a predetermined temperature. The temperature of the reinforcing fiber bundle 2 when the molten resin 3 is supplied is preferably -100 ° C. or higher and + 50 ° C. or lower of the discharge temperature of the molten resin discharged from the T die 12 discharge port. By maintaining the reinforced fiber bundle 2 at a temperature in this range, even if the reinforced fiber 2 has a high thermal conductivity such as carbon fiber, the viscosity increases due to the temperature decrease of the molten resin 3, and impregnation becomes difficult. It can be suppressed. Since the viscosity of the thermoplastic resin changes logarithmically with respect to the temperature, the temperature management of the reinforcing fiber 2 is important.

  The heating means 5 is preferably one by far infrared heating or one by laser heating. Thereby, the reinforcing fiber 2 can be efficiently heated. Although it can be heated to a predetermined temperature by the heating means provided on the base 1, the base 1 has a large heat capacity, and it is necessary to cool the reinforcing fiber bundle impregnated with the resin. For this purpose, it is preferable to provide a heating means for heating the reinforcing fiber 2 separately. Note that the heating means 5 does not need to heat the entire reinforcing fiber 2. It is sufficient to heat the portion to which the molten resin 3 is supplied. The heating means 5 is not limited as long as the reinforcing fiber 2 is heated to a predetermined temperature when the molten resin 3 is supplied to the reinforcing fiber 2, and the heating range, heating time, mounting position, etc. Can be adopted.

  It is preferable to pressurize the reinforcing fiber bundle 2 after impregnating the molten resin 3 with it. This pressurization is preferable because impregnation of the molten resin 3 into the reinforcing fiber bundle 2 is promoted. For the pressurization, pressurizing means 20 for pressurizing with a roller as shown in FIG. 1 can be used. After the impregnation and pressurization of the molten resin 3 into the reinforcing fiber bundle 2, the reinforcing fiber bundle 2 impregnated with the molten resin 3 is cooled to produce a resin base material.

  The molten resin 3 is normally supplied to the reinforcing fiber bundle 2 so that a resin base material having a uniform thickness is manufactured. That is, the molten resin 3 is supplied in a layered manner with a uniform thickness on the upper surface of the reinforcing fiber bundle 2. However, the supply of the molten resin 3 can be performed so as to be further repainted on the first layer, and can also be performed such that it is partially repainted as shown in FIG. In FIG. 2, the layer 3b or the layer 3c is overcoated on the layer 3a. The material of the layer 3a and the layer 3b or the layer 3c may be different. Further, the thickness of the layer 3a, the layer 3b or the layer 3c can be partially varied by changing the discharge amount of the molten resin by changing the discharge pressure and moving speed of the T die.

  The method for producing the fiber reinforced resin substrate according to the present invention has been described above. In the present invention, a fiber-reinforced resin molded body can be suitably manufactured by using a press mold. For example, a resin molded body reinforced with fibers can be suitably produced by the method shown in FIG. In FIG. 3, the reinforcing fiber bundle 2 (or the reinforcing fiber fabric 2) is placed on the lower mold 30 in the press mold provided with the lower mold 30 and the upper mold 40. A molten resin 3 made of a thermoplastic resin is supplied from a resin processing machine 10 having a T die 12. Further, a heating means 5 for the reinforcing fiber bundle 2 is provided. The lower mold 30 and the upper mold 40 are provided with heating / cooling means.

The method for producing the fiber-reinforced resin base material is as follows. First, the reinforcing fiber bundle 2 placed on the lower mold 30 is held by holding the reinforcing fiber bundle 2 at a predetermined temperature by the lower mold 30 and the heating means 5. The molten fiber bundle 2 is impregnated on the upper surface of 2 while supplying the molten resin 3 made of thermoplastic resin from the T die 12 so that a dynamic pressure of 0.01 to 5 MPa is applied as a gauge pressure. Next, the upper mold 40 is closed in the lower mold 30 and the reinforcing fiber bundle 2 impregnated with the thermoplastic resin is pressurized and cooled. Thereby, the resin molded object shape | molded by the predetermined | prescribed shape and fiber-reinforced can be manufactured efficiently.

  The present invention is not limited to the above embodiments. In the present invention, it is possible to produce a resin base material or resin molded body in which reinforcing fiber bundles or reinforcing fiber fabrics are superimposed and impregnated with a thermoplastic resin. Additives can be added to supplement the physical properties and functions of the thermoplastic resin. In addition, the resin base material molded according to the present invention can be layered to form a stronger resin base material, or a resin base material with different functionality can be formed by stacking resin base materials with different properties. .

The test which manufactures the resin molding which consists of a reinforced fiber fabric of carbon fiber and polycarbonate (PC) resin using the press type metal mold | die shown in FIG. 3 was done. As the reinforcing fiber fabric, a carbon fiber fabric in which PAN-based carbon fibers (1K) were opened to a width of 2 mm and plain woven was used. As the PC resin, Panlite (AD5503) manufactured by Teijin Chemicals Ltd. was used. The test was performed under the conditions that the molten resin supply temperature was 330 ° C., the lower mold temperature was 160 ° C., and the carbon fiber surface temperature was the same as the molten resin temperature. The dynamic pressure when the molten resin was supplied was 0.06 MPa . The test was performed under the conditions of a pressing force of 0.5 MPa to 5 MPa and a pressurizing time of 0.5 min, 1 min, 2.5 min, and 5 min.

Resin molding when the molten resin supply temperature is 300 ° C, the lower mold temperature is 160 ° C, the carbon fiber surface temperature is 300 ° C, the press pressure is 0.5 MPa , and the press pressure time is 0.5 min. A good resin molded body having a body thickness of 100-110 μm and carbon fibers impregnated with a resin was obtained.

  The same production test as in Example 1 was performed on the resin molded body made of the reinforced fiber fabric and polypropylene (PP) resin used in Example 1. The test was performed under the same conditions as in Example 1 except that the molten resin supply temperature was ˜260 ° C.

When the molten resin supply temperature is 260 ° C, the carbon fiber surface temperature is 230 ° C, the press pressure is 2.5 MPa, and the press pressurization time is 2.5 min, the thickness of the resin molding is 75 μm, and the resin is applied to the carbon fiber. A good carbon fiber reinforced resin impregnated with was obtained. Similarly, even when the pressing force of the press was 5 MPa and the pressurization time was 0.5 min, a good resin molded body in which the resin molded body had a thickness of 65 μm and carbon fiber was impregnated with the resin was obtained.

The test which manufactures the resin molding which uses a cellulose fiber as a reinforced fiber similarly to Examples 1 and 2 was done. As reinforcing fiber, BEMCOT manufactured by Asahi Kasei Fibers Co., Ltd. was used. When the molten resin supply temperature is 260 ° C, the BEMCOT surface temperature is 230 ° C, the press pressure is 0.5 MPa , and the press pressurization time is 0.5 min, the thickness of the resin molding is 75 μm and the fiber A good resin molded body impregnated with the resin was obtained. In the case of this example, it was possible to produce at a lower temperature and pressure than in the case of carbon fiber.

1 base
2 Reinforced fiber bundle or reinforced fiber fabric
3 Molten resin
5 Heating means
10 Resin processing machine
12 T die
20 Pressurizing means
30 Lower mold
40 Upper mold

Claims (8)

A method for producing a fiber-reinforced resin base material comprising reinforcing fibers and a thermoplastic resin, wherein a molten thermoplastic resin is applied to a top surface of a reinforcing fiber bundle or a reinforcing fiber fabric placed in a flat shape from a T die to a gauge pressure. The fiber is reinforced by impregnating the reinforcing fiber bundle or the reinforcing fiber woven fabric while being supplied with a dynamic pressure of 0.01 to 5 MPa , and cooling the reinforcing fiber bundle or the reinforcing fiber woven fabric impregnated with the thermoplastic resin. Of manufacturing a resin base material.   2. The molten resin is supplied in a state where the surface temperature of the reinforcing fiber bundle or the reinforcing fiber fabric is in a temperature range of −100 ° C. to + 50 ° C. of the discharge temperature of the resin to be supplied. The method to manufacture the resin base material as described in 2.   The method for producing a resin base material according to claim 2, wherein the molten resin is supplied so as to be layered or partially coated.   The method for producing a resin base material according to claim 2, wherein the molten resin is supplied by changing the discharge amount of the resin partially by changing the discharge pressure and moving speed of the T die. .   The method for producing a resin substrate according to any one of claims 1 to 4, wherein the reinforcing fiber bundle or the reinforcing fiber fabric is made of carbon fiber. While supplying molten thermoplastic resin from the T die to the upper surface of the reinforcing fiber bundle or reinforcing fiber fabric placed on the base having heating and cooling means so that a dynamic pressure of 0.01 to 5 MPa is applied by a gauge pressure. A resin substrate reinforced by fiber impregnating a reinforcing fiber bundle or a reinforcing fiber fabric and pressurizing the reinforcing fiber bundle or the reinforcing fiber fabric impregnated with the thermoplastic resin between the base and the roller and then cooling. How to manufacture. In an upper and lower mold having heating and cooling means, a dynamic pressure of 0.01 to 5 MPa is applied from the T die to the upper surface of the reinforcing fiber bundle or reinforcing fiber fabric placed on the lower mold with a gauge pressure from the T die. The reinforcing fiber bundle or the reinforcing fiber fabric is impregnated while being supplied, and then the upper mold is closed to the lower mold and the reinforcing fiber bundle or the reinforcing fiber fabric impregnated with the thermoplastic resin is pressurized and cooled. A method for producing a fiber-reinforced resin molded body. A resin processing machine having a T-die and used for manufacturing a fiber-reinforced resin base material or resin molded body according to claim 1 , wherein the fiber bundle or reinforced fiber fabric is supplied with molten resin. A resin processing machine having a heating means for heating the surface portion of the steel plate to a predetermined temperature.

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