JP2006123417A - Multidirectional fiber-reinforced thermoplastic resin plate, its manufacturing method, manufacturing system, and pressure forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To manufacture fiber-reinforced plate which is impregnated with a thermoplastic synthetic resin. <P>SOLUTION: The multidirectional fiber-reinforced thermoplastic resin plate of this invention is characterized by the manufacturing method, wherein composite braids or composite twist strings whose reinforced fiber bundles are coated with a thermoplastic synthetic resin fiber are set in parallel, this paralleled fiber is laminated in a lengthwise direction, a lateral direction, and a slanting direction to be an integrated fiber sheet, and a single sheet or a plurality of sheets of this fiber sheet are heated and pressurized to be formed to a plate containing reinforced fiber by melting the above thermoplastic synthetic resin fiber. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In this invention, thermoplastic fibers having heat-resistant reinforcing fibers as the core are laminated in parallel in the longitudinal direction, the transverse direction, and the oblique direction, entangled between the fibers, and the laminated fiber sheet bundled with the yarn is heated, The present invention relates to a multi-directional fiber reinforced thermoplastic resin plate intended to be pressed into a fiber reinforced synthetic resin plate, a manufacturing method thereof, and a pressure molding apparatus.

  Conventionally, thermosetting resin composite materials reinforced with glass fibers, carbon fibers, aramid fibers, and the like have characteristics such as excellent strength, light weight, corrosion resistance, and the like, and are used in various fields.

On the other hand, thermoplastic resin composite materials are tough, simplified and shortened in the molding process, abundant in the variety of resin used as a medium, and may be recycled. Since fibers are used, for example, for injection molding, it is said that the strength is lower than that of a thermosetting resin composite material.
JP-A-11-293535 JP-A-5-106116 JP-A-7-111501 JP-A-7-156341

  The thermosetting resin product cannot be reused by molding and has a difficulty in recyclability.

  Further, since the thermoplastic resin has poor impregnation properties, it is difficult to use long fibers, and thus there is a problem that the strength is reduced, but recycling is easy.

  Further, when a thermoplastic synthetic resin fiber is heated and pressed to form a synthetic resin plate, there is a problem of sticking to the pressing surface because the molten resin is impregnated by heating and pressing.

  In addition, since the fiber laminate is heated and pressurized, the air intervening between the fibers must be quickly discharged to the outside world. There is a possibility that bubbles may be incorporated, and therefore there is a risk that the strength is not uniform due to the incorporation of bubbles or the strength is reduced.

  Conventionally known film stacking methods are difficult to apply to complex shapes because of lamination of unimpregnated preforms, and the followability of curved surfaces is improved compared to conventional prepreg materials. However, since an unimpregnated preform is used, the impregnation property is poor, and impregnation has a problem that it takes a long time for molding under high temperature and high pressure.

  Powder impregnated yarn is a powdered thermoplastic resin that is applied to reinforcing fibers to improve impregnation, but the resin powder adheres unevenly and is difficult to control. It has the problem of being. In addition, although the workability is poor because the resin powder spills out, materials for improving workability by covering with an outer shell made of the same resin as the resin powder have been developed to prevent this.

The Coming Red yarn is a mixture of two types of fibers and is excellent in impregnation. However, in order to complete the technology of mixing the reinforcing fibers and the matrix resin, the manufacturing process of the yarn The problem of how to reduce the damage degree of the fiber and how to disperse and mix the fibers having greatly different properties at the same time must be solved. Especially when making Coming Red yarn with carbon fiber as reinforced fiber, the damage of carbon fiber is significant, eliminating the fiber damage, and advanced technology to disperse and mix carbon fiber and matrix fiber uniformly The need for this is also a problem.

  The invention shown in Patent Document 3 is an invention of a composite laminate in which a sheet in which a fiber arranged in one direction is impregnated with a thermoplastic resin is heat-sealed to a resin foam. Is different.

  The invention shown in Patent Document 4 is an invention of a fibrous substance-containing layer, a fiber-reinforced resin plate having the fibrous substance-containing layer, and a method for producing the same, but contains a very short fiber having a fiber length of about 5 mm. However, there is a problem that the strength is extremely inferior, and the use is different by itself. That is, it can be used for building materials that do not require high strength.

  In order to solve the above problems, the present invention uses a reinforcing fiber as a core of a thermoplastic synthetic resin fiber, and the synthetic resin fibers are arranged in parallel in the vertical, horizontal, and diagonal directions, and are laminated in the vertical direction. The above-mentioned conventional problem of insufficient impregnation was solved by attaching a heating plate to a laminate obtained by superimposing one or a plurality of these and heating and pressurizing them.

  Adhesiveness was avoided by interposing a peelable sheet such as polytetrafluoroethylene or a peeled steel plate between the heating plate and the fiber.

  The heating temperature is a temperature at which the resin melts. For example, in the case of a nylon resin, 250 ° C. to 300 ° C. is used. Next, at the time of pressurization, the press surface was subjected to a swing press so as to sequentially come into contact, and the bubbles were discharged to successfully produce a homogeneous plate, thereby solving the conventional problems.

  As the thermoplastic synthetic resin fiber, PEEK fiber, acrylic fiber, nylon fiber, polyurethane fiber, polypropylene fiber, rayon, or the like can be used. As the reinforcing fiber, an aramid fiber, a glass fiber, a ceramic fiber, a carbon fiber, an ultra high molecular polyethylene fiber, or the like can be used.

  That is, in the present invention, a composite braid or a composite twisted cord in which a reinforcing fiber bundle is coated with a thermoplastic synthetic resin fiber is juxtaposed, and the parallel fibers are laminated in the longitudinal direction, the transverse direction, and the oblique direction to form an integral fiber sheet, A multi-directional fiber reinforced thermoplastic resin plate, characterized in that a single sheet or a plurality of sheets of the fiber sheet is heated and pressed to melt the thermoplastic synthetic resin fiber and formed into a plate shape containing reinforcing fibers, Reinforced fiber is a continuous long fiber of aramid fiber, glass fiber, ceramic fiber, carbon fiber, or ultra-high molecular weight polyethylene fiber, and thermoplastic resin fiber is PEEK fiber, acrylic fiber, nylon fiber, polyurethane fiber, polyethylene fiber Polypropylene fiber or rayon continuous long fiber.

Further, the invention of the manufacturing method is a method in which composite braids or composite twisted cords containing reinforcing fibers are juxtaposed, and the parallel fibers are laminated and integrated in the longitudinal direction, the transverse direction, and the oblique direction, respectively, to constitute a fiber sheet, and the fibers A single fiber sheet of a sheet or a laminated fiber sheet obtained by laminating a plurality of sheets is heated to a thermoplastic synthetic resin melting temperature and pressurized to form a resin containing reinforcing fibers, and then cooled and solidified to form a fiber reinforced resin plate. The method for producing a multi-directional fiber reinforced thermoplastic resin plate is as follows. The heating temperature is 200 ° C. to 350 ° C., and the pressing time is 1 minute to 30 minutes. The pressure is sequentially pressurized from one side to the other side, the pressure of the pressure is for the ^{30kg / cm 2 ~70kg / cm 2} , between the pressing surface and the fiber surface during pressurization A mold release means is interposed, and the mold release means performs polytetrafluoroethylene processing on the surface of the thin metal plate or laminates a polytetrafluoroethylene sheet on the thin metal plate.

  Next, the invention of the system is a knitting means using a composite braid containing reinforcing fibers or a composite twisted string as a fiber sheet, a heating and pressurizing means for heating and pressurizing the fiber sheet, a cooling means for cooling to a resin plate, A multi-directional fiber-reinforced thermoplastic resin plate manufacturing system characterized by combining cutting means, and the heating and pressurizing means electrically heats the pressurizing plate and sequentially brings one or both of the pressurizing plates close to each other. Pressure. Furthermore, the pressure plate is a two-axis descent method, and the two axes are installed in series with respect to the traveling direction of the fiber sheet, and the amount of descent of the two axes is provided with a difference in size so that the pressure is sequentially applied. It is a pressure molding apparatus used for manufacture of the multi-directional fiber reinforced thermoplastic resin plate.

  Further, the pressure plate is a biaxial lowering method, the shaft is installed in the series direction with respect to the traveling direction of the fiber sheet, and the pressure is sequentially applied by providing a difference in the amount of lowering the two shafts. It is a pressure molding apparatus used for manufacture of the multi-directional fiber reinforced thermoplastic resin plate.

  The present invention is a synthetic resin plate incorporating reinforcing fibers, and it has been difficult to impregnate the resin evenly in the past, but this invention is a composite in which the periphery of the reinforcing fiber bundle is coated with thermoplastic synthetic resin fibers. Since the fiber sheet braided with the braid or composite twisted string as a material is heated and pressurized, the thermoplastic synthetic resin is evenly distributed not only from the surface but also to the inside. Therefore, when the thermoplastic synthetic resin is melted, the whole becomes a synthetic resin melt uniformly, and the reinforcing fibers are integrally embedded therein.

The heating temperature varies depending thermoplastic synthetic resin, wherein a 200 ° C. to 350 ° C. As the pressure is a 30kg ^/ cm ² ~70kg ^/ cm 2 as described above, a relatively short period of time ( For example, it is preferable that the uniform impregnation is performed within 1 to 30 minutes, preferably within about 1 minute.

  However, when the uniform impregnation state is obtained, it is quickly cooled (for example, blown with cold air of 5 ° C. to 15 ° C.) and released. In the above, it is a pressure plate (metal flat plate) because it is pressurized by a press machine, but since the adhesive force is high, the steel sheet for release is subjected to polytetrafluoroethylene processing, and the contact type It is preferable to interpose between the fiberboard and the fiberboard.

  As the mold release, a polytetrafluoroethylene sheet or the like can be considered, but it is necessary to deal with the cooling for mold release. For example, for cooling, it is conceivable to apply polytetrafluoroethylene processing to a steel plate, an aluminum plate or the like having a high thermal conductivity.

  In consideration of processing efficiency, it is preferable to rotate it endlessly as a release belt (ultra-thin steel plate belt or polytetrafluoroethylene belt), and when it is impossible to make a belt, it can also be used as a release plate. .

  Since the fiber sheet in the said invention contains a lot of air, if it heat-presses as it is, it will contain a lot of bubbles. Therefore, the pressure plates are sequentially pressurized so that air is released in one direction. The pressurization speed in this case varies depending on the viscosity of the synthetic resin, but for example, in the case of nylon fiber, it is about 1 minute. Further, when two pressurizers are arranged in parallel, there are cases where the pressurization is performed sequentially and simultaneous pressurization at two locations. In any case, it is preferable to devise so as to generate bubbles and to form bubbles at the time of curing.

  In the present invention, reinforcing fibers are embedded in a predetermined amount, a predetermined position, and a predetermined density in a thermoplastic synthetic resin plate so as to obtain the same strength as the thermosetting synthetic resin plate.

  Many of the thermoplastic synthetic resin plates are formed by extrusion molding (including injection molding) of molten synthetic resin mixed with short fibers. However, this manufacturing method cannot embed long fibers (for example, 1 m or more). It is.

  Therefore, it is conceivable to supply a thermoplastic synthetic resin from above the long-fiber knitted fabric and press-mold it. However, if synthetic resin is supplied to the long-fiber knitted sheet, the permeability of the synthetic resin is poor, resulting in a non-uniform material. This causes a decrease in strength.

  In order to solve the above-mentioned problems, the present invention makes a thermoplastic synthetic resin string having a strength fiber as a core, makes a knitted product with this string, laminates this to an arbitrary thickness, and then heats, A synthetic resin plate is molded by applying pressure.

  As a result, the thermoplastic synthetic resin is interposed at various thicknesses, and the reinforcing fibers are endless (continuous as long as necessary), so that the strength is remarkably improved, and the almost thermosetting fiber reinforced synthetic resin plate is formed. They succeeded in obtaining a synthetic resin plate with comparable strength.

  According to this invention, composite braids or composite twisted cords in which reinforcing fiber bundles are coated with thermoplastic resin fibers are juxtaposed, and the parallel fibers are laminated in the longitudinal direction, transverse direction, and oblique direction to form an integral fiber sheet, Since the thermoplastic synthetic resin is interposed between the reinforced fibers, heating it is effective to be in an impregnated state in a short time (the advantage is that the impregnated state can be equalized). .

  In addition, since pressurization is sequentially performed during pressurization, there is an effect that the air contained in the fiber sheet is rationally discharged to obtain a homogeneous synthetic resin plate having no bubbles.

  Further, since the reinforcing fibers are evenly arranged in the vertical, horizontal, and diagonal directions, there is an effect that a synthetic resin plate with reinforcing fibers of uniform strength can be obtained.

In the present invention, a composite braid or a composite twisted cord having a carbon fiber bundle as a core and a thermoplastic synthetic resin fiber (for example, acrylic fiber or polyurethane fiber) coated on the outside thereof is juxtaposed. After sequentially laminating in the direction and oblique direction, they are bound with stitch yarns to form a fiber sheet, and a plurality of the fiber sheets are stacked and then heated to 250 ° C. and pressurized at 40 kg / cm ² to produce the thermoplastic composition. A multidirectional fiber reinforced thermoplastic resin plate and a method for producing the same, wherein the resin is dissolved and impregnated inside and outside of the reinforcing fiber, and then cooled and released. Accordingly, the reinforcing fibers are strips, but the thermoplastic fibers are melt-molded resin plates.

  Moreover, a composite braid or a composite twisted string is manufactured by a conventional technique, and the composite braid or a composite twisted string is knitted by a conventional technique to form a fiber sheet, and the fiber sheet is heated to the melting temperature of the resin used and pressurized to be integrated. This is a system for producing a multi-directional fiber reinforced thermoplastic resin plate by combining various processing means for making a synthetic resin plate.

  The fiber sheet was heated and pressed in order from one side to the other side to extrude the air contained between the fibers, thereby forming a special pressing device.

  An embodiment of the present invention will be described with reference to the drawings. A composite braid 4 in which a plurality of nylon fiber bundles 2 (for example, 10 to 20 nylon fibers) are incorporated outside a carbon fiber bundle 1 (for example, 10 to 20 carbon fibers). Alternatively, a composite twisted string 3 (FIGS. 1A and 1B) in which a plurality of nylon fiber bundles 2 (for example, 10 to 20 nylon fibers) are wound around a carbon fiber bundle 1 (for example, 10 to 20 carbon fibers). Are laminated in diagonally parallel (a), laterally parallel (b), diagonally parallel (a), and longitudinally parallel (c) from the bottom, and then integrated with the overlying threads 5 and 5 to produce a fiber sheet 6 (FIG. 2). (A)). This fiber sheet 6 can also be made into two layers in the horizontal parallel (b) (FIG.2 (b)).

  The fiber sheet 6 is wound into a roll shape, and is laid up and down as fiber rolls 7 and 7, pulled out and stacked, and heated and pressed (FIG. 3A).

  Although the above description has been made on the lamination of two sheets, if the fiber rolls 7 and 7 are installed on two upper and lower bundles (FIG. 3B), four sheets can be laminated. Therefore, although there is no restriction | limiting in the number of lamination | stacking, normally 2 sheets-4 sheets are used.

  From the fiber rolls 7, 7, the fiber sheets 6, 6 are unwound (or four fiber sheets 6 are unwound) and fed into the processing apparatus 10. In the processing apparatus 10, a tension machine 8, a preheater 9, a heating and pressurizing machine 11, a cooler 12, a tension machine 13, and a cutting machine 14 are sequentially arranged in series, and are installed on a machine body 15. In the figure, 16 is an air supply device, and 17 is an exhaust duct (FIG. 3).

  In the said Example, after drawing the laminated sheet of the fiber sheet 6 with the tension machine 8 as shown by the arrow 18 in FIG. 3 and preheating to 150-200 degreeC with the preheater 9, it is heated like the arrow 19, Feed into pressurizer 11.

  The heating and pressurizing machine 11 is provided with a pressurizing stand 20 (FIG. 4A), and the laminated sheet 6a of the fiber sheet 6 is pulled out intermittently as indicated by an arrow 19. The pull-out amount is determined by the length of the pressure heads 21 and 21 of the pressure stand 20, for example.

  Heat plates 21 a and 22 a are fixed inside the pressure head 21 and the cradle 22 and are heated to, for example, 300 ° C.

  The left and right ends of the pressure head 21 are connected to the rods 24 and 24a of the hydraulic cylinders 23 and 23a, respectively, and are lowered corresponding to the lowering of the rods 24 and 24a (arrows 25 and 26). Therefore, as shown in FIG. 4D, when the rod 24 is lowered early and the rod 24a is lowered with a delay, the pressure head 21 descends obliquely and is sequentially pressurized as shown in FIG. 4D. . Therefore, the air contained in the fiber sheet 6a is rationally excluded as indicated by an arrow 27 (no bubbles remain). In the above, the descending speed of the rod 24 is made slower than that of the rod 24a.

  Since the thermoplastic synthetic resin of the fiber sheet 6a melts and adheres at the time of the heating and pressurization, the fiber sheet 6a, the heating plate 21a of the pressure head 21 and the cradle 22 are used as shown in FIG. A steel sheet 29 having a polytetrafluoroethylene film 28 layered (for example, laminated) is sandwiched between it and the heating plate 22a to prevent thermal bonding.

  The steel sheet 29 is clamped to the tension machine 13 through the cooler 12. Therefore, even when the fiber sheet 6a is heated and its tensile strength is lowered, the fiber sheet 6a is sandwiched between the steel sheets 29 that have been sandwiched, so that there is no possibility of insufficient tensile force.

  As described above, if the processed fiber sheet becomes the fiber reinforced plate 6b, the adhesiveness is lost and the strength is remarkably increased. Therefore, there is no problem even if a direct tensile force is applied.

  Regarding the feeding of the fiber sheet 6a and the removal of the fiber reinforced plate 6b, the tension machines 8 and 13 are illustrated as rollers. However, the tension machines 8 and 13 are merely abstract views. The tensioning machine can be used.

  The fiber reinforced plate 6b formed as described above is cut into a fiber reinforced single plate 6c by a cutter 14 into a predetermined length (for example, 1 m to 2 m), and the conveyor 30 proceeds to the next step as indicated by an arrow 31. Carried.

  The fiber reinforced single plate 6c is in a state where a carbon fiber bundle is embedded in the thermoplastic resin 32, and exhibits a strength (approximately 80% or more) close to the strength of the thermosetting resin plate.

(A) A partially enlarged view of a composite twisted string used in the present invention, (b) A partially enlarged view of a composite twisted braid. (A) The perspective view of a fiber sheet similarly, (b) The perspective view of another fiber sheet. (A) The schematic diagram of a processing apparatus, (b) The figure which similarly shows lamination | stacking of a fiber sheet. (A) Explanatory drawing at the time of processing, (b) Illustrated enlarged sectional view for retaining the peelability, (c) Partial enlarged sectional view, (d) Explanatory drawing of sequential pressurization. The partial cross-sectional enlarged view of a fiber reinforced board similarly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbon fiber bundle 2 Nylon fiber bundle 3 Composite braid 4 Composite twisted string 5 Overhang yarn 6 Fiber sheet 7 Fiber roll 8 Pulling machine 9 Preheating machine 10 Processing apparatus 11 Heating and pressing machine 12 Cooling machine 13 Pulling machine 14 Cutting machine 15 Machine body 16 Air inhaler 17 Exhaust duct 20 Pressure stand

Claims (11)

  Composite braids or composite twisted cords in which reinforcing fiber bundles are coated with thermoplastic synthetic resin fibers are juxtaposed, and the parallel fibers are laminated in the longitudinal direction, the transverse direction, and the oblique direction to form an integral fiber sheet, and the single fiber sheet A multi-directional fiber reinforced thermoplastic resin plate, wherein a sheet or a plurality of sheets are heated and pressed to melt the thermoplastic synthetic resin fibers and formed into a plate shape containing reinforcing fibers.   The multidirectional fiber-reinforced thermoplastic resin plate according to claim 1, wherein the reinforcing fibers are continuous long fibers of aramid fibers, glass fibers, ceramic fibers, carbon fibers, or ultrahigh molecular weight polyethylene fibers.   The multi-directional fiber reinforced thermoplastic resin plate according to claim 1, wherein the thermoplastic resin fiber is a continuous long fiber of PEEK fiber, acrylic fiber, nylon fiber, polyurethane fiber, polyethylene fiber, polypropylene fiber, or rayon.   A composite braid or composite twisted string containing reinforcing fibers is juxtaposed, and the parallel fibers are laminated in the longitudinal direction, the transverse direction, and the oblique direction, respectively, to form a fiber sheet, and a single fiber sheet or a plurality of the fiber sheets Multi-directional fiber reinforced heat characterized in that laminated fiber sheet with laminated sheets is heated to thermoplastic synthetic resin melting temperature and pressed to make resin with reinforced fiber, then cooled and solidified to make fiber reinforced resin plate Manufacturing method of plastic resin board.   The method for producing a multidirectional fiber-reinforced thermoplastic resin plate according to claim 4, wherein the heating temperature is 200 ° C to 350 ° C, and the pressing time is 1 minute to 30 minutes. Pressure is sequentially pressurized from one side to the other side, the pressure of the ^{pressurization, 30kg / cm 2 ~70kg / cm} 2 and according to claim 4, wherein the characterized in that the multidirectional fiber-reinforced thermoplastic resin sheet Manufacturing method.   5. The method for producing a multi-directional fiber-reinforced thermoplastic resin plate according to claim 4, wherein a releasing means is interposed between the pressing surface and the fiber surface during pressing.   8. The multidirectional fiber-reinforced thermoplastic resin plate according to claim 7, wherein the releasing means performs polytetrafluoroethylene processing on the surface of the thin metal plate or laminates a polytetrafluoroethylene sheet on the thin metal plate. Manufacturing method.   Combining knitting means using a composite braid containing reinforcing fibers or a composite twisted string as a fiber sheet, a heating and pressurizing means for heating and pressurizing the fiber sheet, a cooling means for cooling to a resin plate, and a cutting means A system for producing a multi-directional fiber reinforced thermoplastic resin board characterized by   The system for producing a multi-directional fiber reinforced thermoplastic resin plate according to claim 9, wherein the heating and pressing means heats the pressure plate electrically and simultaneously presses one or both of the pressure plates in close proximity.   The pressure plate is a two-axis descent method, and the two axes are installed in series with respect to the traveling direction of the fiber sheet, and the amount of descent of the two axes is provided with a difference in size so that the pressure is sequentially applied. A pressure forming apparatus used for manufacturing a multi-directional fiber reinforced thermoplastic resin plate.

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