JPS61229535A - Method and device for manufacturing fiber reinforced resin sheet - Google Patents

Abstract

PURPOSE:To permit to orientate continuous fibers without turbulence and control the degree of crystallization in accordance with the characteristics of the resin by a method wherein a plurality of continuous fiber sheets is orientated into one direction and is heated to a temperature higher than the softening point of a thermoplastic resin to form the coating film of thermoplastic resin on the surface thereof. CONSTITUTION:The thermoplastic resin is molten in an extruding machine 14 to extrude it from a die provided at the tip end of the extruding machine and coat it on the surface of a heated resin coating film providing roll 15. The fiber sheet 10 contacts with the roll, provided with the coating film of resin in such manner, and the resin is impregnated between fibers. Impregnation is achieved by the arrival of the coating film of resin to the rear surface of the fiber sheet through filaments constituting the fiber sheet. The contact pressure between the fiber sheet and the roll is such a degree that the sheet can be arrived at the surface of the roll under pushing through the coating film of the resin. The contact pressure is regulated by a tension applied on the fiber sheet. The fiber sheet 10, coated with the resin, is pressed by a heating roll 17 to improve the degree of impregnation of the resin, thereafter, is cooled and is taken off. The temperature of these heating rolls 17 is higher than the softening pint of the resin impregnated into the cloth.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a fiber-reinforced resin sheet and an apparatus therefor. ', [Prior Art] As a method for producing a fiber reinforcing composition by impregnating fibers with a thermoplastic resin, as described in JP-A No. 55-77525, a fiber mat and a thermoplastic resin are impregnated with a fiber mat and a thermoplastic resin. A plasticizer is added to a thermoplastic resin as described in the φ method in which the resin is melted by applying heat and pressure and impregnated into a fiber mat, and then the pressurized state is turned off, or as described in JP-A-59-47234. A known method is to reduce the melt viscosity by impregnating the plasticizer into fibers, and then volatilize the plasticizer.

However, each of the above methods has significant drawbacks. That is, in the method described in JP-A-55-77525, when the pressure is increased to eliminate air bubbles, that is, voids that cause molding defects, a resin flow is generated, which disturbs the arrangement of the fibers and causes miscellaneous cutting. It has its drawbacks.

On the other hand, in the method described in JP-A No. 59-47234, plasticity is the biggest bottleneck, and the thermal process for removing the plasticizer causes deterioration of the thermoplastic resin and the performance of the resulting composition due to the residual plasticizer. It has disadvantages such as change.

[Problems to be solved by the invention] □ The present invention solves the problem of high viscosity thermoplastic □
A technical object of the present invention is to provide a method and apparatus for manufacturing a fiber-reinforced resin sheet that sufficiently impregnates the fibers and does not disturb the fibers even when resin is used.

[Means for Solving the Problems] The present invention has been made as a result of repeated efforts to solve the above problems.

Specifically, the method for producing a fiber-reinforced resin sheet according to the present invention is a method for producing a fiber-reinforced composition by impregnating fibers with a thermoplastic resin, in which a plurality of continuous fiber sheets being pulled and conveyed are The fiber sheet is aligned in one direction to form a sheet, and the fiber sheet is heated to a temperature higher than the softening point of the thermoplastic resin, and is applied to at least one resin coating roll having the thermoplastic resin coating on the surface. The apparatus for producing a fiber-reinforced resin sheet according to the present invention is characterized in that the fiber-reinforced resin sheet manufacturing apparatus according to the present invention aligns a plurality of continuous fibers in one direction to form three sheets. , an apparatus for manufacturing a fiber-reinforced resin sheet in which the sheet is impregnated with a thermoplastic resin/resin, which includes a fiber ml & outlet section having a plurality of bobbins for supplying fibers and a mechanism for adjusting tension during fiber feeding; It has a supply section in which the cones are aligned in one direction to form a sheet-like shape, and at least one resin coating roll heated above the softening point of the thermoplastic resin, and the roll is coated with the thermoplastic resin. It is characterized by comprising a resin impregnating section having an extruder and a die for applying a coating film, and a taking-off section for cooling and taking off the sheet that has passed through the impregnating section. '1 Below, one aspect of the present invention will be explained in detail. ``...In the present invention, a plurality of continuous fibers refers to ``a plurality of filament aggregates that constitute fibers known as rovings, yarns, and tows, and the filaments are sufficiently long and , which has sufficient strength to pull against a molten thermoplastic resin coating under the conditions of use.

Preferred materials include glass fiber and carbon fiber.

Examples include highly elastic synthetic resin fibers, as well as inorganic fibers such as silicon carbide fibers, alumina fibers, and titanium fibers.

Metal fibers such as boron fibers and stainless steel can also be used.・ .

The synthetic resin fiber is preferably surface-treated to have adhesive properties with the thermoplastic resin to be impregnated, and it is also necessary that the properties such as strength do not change at the melting temperature of the thermoplastic resin used. Examples of one resin fiber include aramid fiber 111 (registered trademark [Kevlar], etc.).

゛The glass fibers and carbon fibers are preferably coated with a surface treatment agent such as a silane-based or titanium-based coupling agent on the fiber surface in order to improve adhesion with the thermoplastic resin used. In addition, it is preferable for handling to use a sizing agent so that the rovings and tows do not unravel during handling.

゛ In the present invention, continuous fibers are formed by arranging a plurality of continuous fibers in parallel in one direction, for example, in the machine direction, spreading them in the width direction while being controlled so as not to cross each other, and adjusting the thickness to an appropriate thickness to form a sheet. Ru. Specifically, continuous fibers are wound around multiple bobbins, and the fibers are fed out from each bobbin while applying an appropriate tension, and are arranged in a line with an appropriate width in the machine direction in a sieve-like shape. Preferably, they are arranged in a sheet through the container.

The thickness of the sheet depends on the thickness of the fibers M (E7-pings and tows) used, but it depends on the widthwise arrangement of the rovings and tows,
Can be controlled by density. The thickness accuracy affects the variation in the impregnation state, so it is preferably within ±10% of the target thickness.There is no particular thickness restriction, but the thickness is 10JJ, m
If the size is larger, fiber breakage can be prevented, while 1,0
If it is made thinner than OOIL■, the degree of resin impregnation will be high and there will be fewer ribs and molding defects will not occur.

When arranging fibers into sheets, it is effective to increase the humidity of the working environment in order to prevent fiber filaments from breaking due to friction when they pass through guide rollers or aligners.

In the sheet thus obtained, it is necessary that uniform tension be applied to each roving or tow so that each roving or tow does not intersect. 'Next, in impregnating the sheet with a thermoplastic resin, the thermoplastic resin used is
Polystyrene, polyvinyl chloride, high density, polypropylene, polypropylene, nylon, polycarbonate,
Polybutylene terephthalate, polyethylene terephthalate, etc. are used, but are not limited thereto.

□ Note 4: When the resin sheet obtained according to the present invention is used for applications requiring structure and strength, it is preferable that the resin has a high modulus of elasticity and high tensile strength.
Specific examples include 7 polyether sulfone, polysulfone, polyetherimide (trademark rto, to J)
High grade engineering resins such as , polyetheretherketone, etc. are preferred.

When using these resins, it is preferable to dry them in advance, and it is even more preferable to add a titanium-based coupling agent to the resin for the purpose of improving adhesion to the fibers. The resin coating is extruded from a goo installed at the tip of the extruder and applied to the surface of the heated resin coating roll.
It is sufficient to have one, but it is also possible to provide more than one. The resin temperature is preferably higher in order to lower the resin viscosity, but it can be determined individually based on the relationship with the thermal deterioration temperature of each resin. It is preferable that the surface temperature of the roll to which the resin is applied is the same as or higher than the resin temperature.The width of the resin coating film should be equal to or greater than the width of the fiber sheet, and the thickness of the coating film should be equal to or higher than the resin temperature. The thickness is adjusted to suit the thickness of the sheet. This thickness is a value determined experimentally by setting a target value for the resin content in the finally obtained fiber-reinforced sheet.

On the other hand, the thickness accuracy depends on the above-mentioned resin content in the width direction + capital/
Iwao - ÷ Su + Heji Se9machi λjiyoku Iy: +10% is preferable, and more preferably within ±5%.

: In this way, it is a coating method that improves the thickness accuracy of the coating film.It is possible to use a normal method.For example, a method using a doctor, a method using a coating roll □ between a goo and a roll ( There are roll coater methods), etc.

The fiber sheet thus comes into contact with the roll provided with the resin coating, and impregnation of the fibers with the resin begins. Impregnation is achieved when the resin coating passes between the filaments that make up the fiber sheet and reaches the back side of the fiber sheet, so the contact pressure of the MAA sheet to the roll is determined by the pressure of the sheet pushing the resin coating apart. It is sufficient that it can reach the sail surface, and the contact pressure of the dragon is adjusted by the tension applied to the fiber sheet. If this tension is too strong, the resin coating will not pass between each filament of the fiber sheet and will be pushed to both ends of the fiber sheet in the width direction, so the tension must be determined according to the viscosity of the resin used. The contact length between the fiber sheet and the roll is 174 mm of the roll circumference.
~3'/4 is preferred.

The resin-coated fiber sheet is then pressed against, for example, one or more heated rolls to improve the degree of impregnation, and then cooled and taken off. The temperature of these heating rolls is above the softening point of the resin to be impregnated.

In this specification, the softening point refers to the lowest temperature that can be measured using a melt index measuring device under a load of 5 kg.

If the blood in contact with the resin coating roll is the front side of the fiber sheet, then the back side is placed on the next first heating roll, the front side is placed on the next heating roll, and so on, and so on alternately. The fiber sheet and the roll are brought into contact so that the resin present on one surface or the back surface while in contact flows between the filaments of the fiber sheet in alternating directions from the front surface to the back surface and then from the back surface to the surface. This is preferable, and by doing so, the degree of impregnation can be improved. 1...(.

In addition, the heating roll installed after the resin coating roll has the effect of improving impregnation and also removes excess resin on the front or back surface of the fiber sheet, but only the resin coating roll If the purpose of impregnation is achieved in , it is not necessary to provide the heating roll.

In the present invention, the number of rolls is influenced by the characteristics of the resin used, but it is sufficient to have 1 to 5 rolls including the resin coating roll, but if 5 or more rolls are installed, the type of resin used It is an extremely effective means to adjust the number of rolls to be heated to the required number.

The impregnating action of the present invention is such that when the fiber sheet contacts the resin-coated sail, the opposite side of the fiber sheet is open, which may cause voids when impregnating the fiber sheet with resin from the roll side, for example. The feature is that it is possible to push air bubbles etc. to the open side.

In the present invention, it is preferable to remove the resin adhering to the roll surface with a dowel plate or the like, since this has the effect of controlling the resin content and smoothing the surface of the fiber sheet.

The resin coating is applied from the die, and the area from the position where the resin is applied to the roll to the rear end of the final heating port is surrounded by a metal plate, and placed in an inert gas atmosphere such as nitrogen to prevent oxidation of the resin. Preventing deterioration is preferable from the viewpoint of the performance of the resulting product, and also helps in keeping the roll and resin warm.
・Next, it was impregnated with resin. Fiber sea-
Regarding the cooling of the For crystalline resins, the crystallinity and grain size are affected by the cooling rate, so by adjusting the cooling rate depending on the resin used, the crystallinity and grain size of the resin in the fiber sheet can be adjusted. It is preferable to control 0. The cooling rate can be adjusted by providing a heating zone between the roll and the take-up machine and creating a temperature gradient in the heating zone to achieve slow cooling. A method such as rapid cooling by spraying onto a miscellaneous sheet may be adopted. ′
- Next, the details of the present invention will be explained with reference to representative embodiments shown in the drawings. ',・m I RA l+ shiAriζ [1111-'ii
2*f! m & y +Ill ■-(a ?i
Fig. 2 is a plan view of the same as above, Fig. 3 is a sectional view showing the structure of the pobbin wrapped with continuous fibers, and Fig. 4 is an aligner that collects and arranges continuous fibers to form a fiber sheet. 5 is a plan view of the same, and FIG. 6 is a side view showing details of the resin-impregnated portion. Although each figure shows only half of the entire fiber sheet, it is of course possible to form a fiber roll over the entire fiber sheet.

As shown in FIGS. 1 and 2, the manufacturing apparatus for carrying out the method of the present invention comprises a fiber delivery section 1, a supply section 2, a resin impregnation section 3, and a take-off section 4.・□、Textile and fiber feeding section 1. A continuous wire m wound around a plurality of pobbins 6 attached to a frame 5
7 as many fibers as required. As shown in Fig. 3, the pobbin 6 has a pobbin main body B1 fixed to a shaft 82; the shaft 62 is rotatably attached to a bearing 63. Since the fiber sheet is pulled by the driving force of the resin impregnated section 3, the shaft 82 is equipped with a brake belt for tension adjustment to adjust the tension at which the fibers are pulled out from the pobbin 6. 84 is attached, and by adjusting the friction between the brake belt 64 and the shaft B2, it is possible to adjust the tension applied to the fibers.

This tension is necessary to prevent a large number of fibers from becoming entangled with each other when they are fed out, and to obtain a fiber sheet with no disorder in the fibers after alignment, and it is preferable that each bobbin 6 has the same tension.

The continuous fibers 7 fed out from the bobbin main body B1 are arranged horizontally by a guide roll 8, and are arranged by an aligner 9 at arbitrary fiber intervals and in arbitrary groups to form a fiber sheet 10. As shown in FIGS. 4 and 5, the aligner 9 consists of a picture frame with a large number of steel wires 8.l stretched across it, and continuous fibers 7.
are aligned by passing through the gaps between the steel wires 81 one by one. (The aligner 9 has a bearing 92 and has a structure that allows the angle to be changed in the direction of the arrow as shown in FIG. The width and thickness of the lO can be adjusted. 83 is a set screw that is fixed after selecting an arbitrary angle of the aligner 9.

By fixing with this set screw 93, it is possible to prevent the width and thickness of the fiber sheet 10 from changing during operation. Although FIGS. 1 and 2 show an example in which one aligner 9 is used, a plurality of aligners 9 may be used as required.

Next, the fiber sheet IO is controlled to have a uniform tension over its entire width by a tension adjustment roll 11 having a brake 12, and is supplied to the resin-impregnated section 3. The surface of the tension adjustment roll 11 is preferably made of rubber or the like so that the tension can be easily adjusted by frictional resistance.There is no particular restriction on the tension. The tension adjustment roll 11 may not be used as long as there is no disturbance between the tension adjustment rolls 11 and 11, as long as the tension adjustment roll 11 can uniformly adjust the tension of all the bobbins 6 at the m1atih exit portion l.

The fiber sheet 10 enters the resin impregnating section 3, where the plasticized thermoplastic resin is extruded into a resin coating roll (hereinafter referred to as
The first heating roll (hereinafter referred to as the 20th roll) 1B, the second heating roll (hereinafter referred to as the 30th roll), 17 to sufficiently impregnate the resin, and then slowly cooled while passing through an annealing furnace 18.
Dies 13 and 3 pieces (7) H that are picked up and picked up by the picking up section 4
-/L/15.16.1'7 is heated to a temperature corresponding to the melt viscosity of the thermoplastic resin used, and suitable heating methods include a heat transfer heater or induction heating.

The three rolls 15.1B and 17 are driven by the motor 1B, and each roll rotates at the same circumferential speed, and the fiber sheet 1
0 and unwinding the continuous fiber m7 from the bobbin 6.

In the embodiment shown in FIGS. 1 and 2.

Although the number of rolls is 3, it is not limited to this, for example, it may be only 10th to 15th roll, or 3 rolls.
In addition to the rolls 15.1B and 17, several heating rolls may be added, and each roll is configured to be driven by one motor 1B, but even between each roll the fiber sheet lO The tension can be adjusted by attaching a separate motor to each roll and controlling the motor load, or by installing a clutch on the drive shaft of each roll to adjust the tension. Adjustments can also be made. Next, the resin-impregnated portion 3 will be explained in detail based on FIG. That is, 4. , the mature plastic resin supplied from the extruder 1a14 (see Figure 2) enters the manifold 35 of the die 13,
The first. Roll 15 and die 13
It enters the section formed by , and comes into contact with the surface of the 10th rule 15 . A doctor 31 is installed at the rear end of the die 13.
．． This doctor 3.l controls the resin coating on the 10th roll 15 and the fabric thickness.Then, the 1st roll 15, which has a resin coating film on its surface, rotates in the direction of the arrow, and the fiber and cone sheet 10 are regulated. come into contact with Appropriate tension is given to the fiber sheet) 1G, and this tension presses it against the surface of No. 10-15, and the resin coating on the surface of No. 10-15 becomes the fiber sheet) 1.
0, the resin' seeps out onto the surface of the fiber sheet) 1G.
The thickness of the resin coating film is preferably such that it passes through the fiber sheet 10 and oozes out onto the surface of the fiber sheet 31G to form a coating film. With the side surface in contact with the 20th rule 18, the fiber sheet 1
By pressing the resin coating film formed on the surface of No. 0 onto the surface of No. 20-Rule 18, the resin flows in the opposite direction to that for No. 10-Rule Is, improving the degree of impregnation. Furthermore, fiber sheet 1
G is also in contact with the 30th rule 17, and the degree of impregnation is further improved.

Each roll Is, "' 1B, 17 is provided with a scraper 32, 33, 34 for scraping off the resin coating film attached to the surface, and the resin and fiber sheet '1 is always kept clean on the surface.
0, so that the amount of resin impregnated into the fiber sheet IO does not change. Reference numeral 38 denotes a heat insulating cover, and in addition to the heat insulating effect of each roll 15, 18, and 17, this heat insulating cover 38 is impregnated by introducing an inert gas such as nitrogen into the heat insulating cover 38 (not shown). It also plays a role in preventing oxidative deterioration of resins.

Next, the fiber sheet IO enters the lehr 18 and is cooled at a cooling rate depending on the resin used. As a method of controlling the cooling rate, a method of controlling the exit from the slow cooling furnace 19 is preferable.

When a crystalline resin is used, it is possible to increase the degree of crystallization by slow cooling, to make it into an amorphous state by rapid cooling, and to perform control according to the purpose.

The fiber sheet 1G obtained in this way is taken off by the taking-off roll 20 of the taking-off section 4 while applying tension.

It is wound up on the winding shaft 22. In addition, 21 is the take-up roll 2
0 and the winding shaft 22.

[Effects of the Invention] As described above, according to the present invention, continuous fibers can be arranged without disorder, and thermoplastic resin, which cannot be impregnated between fibers due to its viscosity when melted, can be easily impregnated. Furthermore, the degree of crystallinity can be controlled depending on the characteristics of the resin used.

[Example] The present invention will be explained below with reference to Examples.

Example 1 The specifications of each part of the apparatus shown in FIGS. 1 and 2 are as follows: number of bobbins is 200, extruder is 40mmφ, width of 1st to 30th loops is 4.
00 m5 and a roll diameter of 25 mm and a diameter of 25 mm was used.

Continuous fiber is carbon edge 1ll (Besphi) HTA-? −
300'0)"j as a thermoplastic resin, one etheretherke)y (IC1, VICTREX PE
EK) tt was used. The viscosity of this polyetheretherketone was 7000 poise at a temperature of 380 DEG C. and a shear rate of 100 sec@-1.

The continuous fibers drawn out from the 2'00 bobbins are
They were aligned to form a fiber sheet with a width of 20 cm.゛Meanwhile, 1. Polyether ether ketone heated and melted at 380°C in an extruder is transferred to the second [d] heated to 400°C.
The fiber sheet was applied to the surface of the 10th rule with a tension of 20 kg. The fiber sheet moved at a speed of 50 centimeters per minute and came into contact with the 20th wheel, which was maintained at the same temperature as the 10th wheel, and then the 10th wheel.
The polyether ether ketone in the fiber sheet was impregnated by contacting the 30th ring at the same temperature as the 140°C
After being slowly cooled in an annealing furnace maintained at a constant temperature, the material was rolled up using a winding machine.

The obtained sheet had a resin content of 50% by weight and a thickness of 0.01 mm. The fibers were undisturbed and there were no voids between the fibers.

Examples 2 to B The specifications and operating conditions of the device used in Example 1 were
Resin-impregnated sheets were obtained with changes as shown in the table.

As is clear from Table 1, it can be seen that according to the present invention, various types of continuous fibers can be obtained without disorder in the fibers and without voids between the fibers.

,,　　　　　　　The following margin

[Brief explanation of drawings]

Fig. 1 is a schematic side view showing one embodiment of the present invention, Fig. 2 is a plan view of the same as above, Fig. 3 is a sectional view showing the structure of mounting a bobbin wound with continuous fibers, and Fig. 4 5 is a front view of an aligner for collecting and arranging continuous fibers to form a fiber sheet, FIG. 5 is a plan view of the same, and FIG. 6 is a side view showing details of the resin-impregnated portion. In the figure, 1 is a fiber at & output part, 2 is a supply part, 3 is a resin impregnated part, and 4 is a take-off part. Patent applicant: Nobuaki Sakaguchi, Patent Attorney, High Performance Wood - New Manufacturing Technology Research Association (1 other person)

Claims (5)

[Claims] (1) In a method for producing a fiber reinforcing composition by impregnating fibers with a thermoplastic resin, a plurality of continuous fiber sheets being pulled and conveyed are aligned in one direction to form a sheet shape, and the fiber sheet is Production of a fiber-reinforced resin sheet, which is heated above the softening point of the resin and passed through while in contact with at least one resin coating roll having the thermoplastic resin coating on the surface, and then cooled. Method. (2) After passing the fiber sheet in contact with a resin coating roll, before cooling it, pass it in contact with one or more heating rolls heated above the softening point of the thermoplastic resin. A method for producing a fiber-reinforced resin sheet according to claim 1, characterized in that: (3) After bringing the fiber sheet into contact with the resin coating roll, the surface opposite to the surface in contact with the resin coating roll is
The method for producing a fiber-reinforced resin sheet according to claim 2, wherein the fiber-reinforced resin sheet is brought into contact with the second heating roll. (4) In an apparatus for manufacturing a fiber-reinforced resin sheet in which a plurality of continuous fibers are aligned in one direction to form a sheet and the sheet is impregnated with a thermoplastic resin, a plurality of bobbins and fibers are provided for supplying the fibers. a fiber feeding section having a mechanism for adjusting tension during feeding; a feeding section that arranges the fibers in one direction to form a sheet; and at least one old coating heated to a temperature equal to or higher than the softening point of the thermoplastic resin. Equipped with a resin impregnating section having a film-applying roll, an extruder and a die for applying a thermoplastic resin coating to the roll, and a taking-off section that cools and takes off the sheet that has passed through the impregnating section. A manufacturing device for a fiber-reinforced resin sheet. (5) The resin impregnation section has one resin coating film application roll, an extruder and a die for applying a thermoplastic resin coating film to the roll, and after the resin coating film application roll, a thermoplastic resin coating film is applied. 5. The apparatus for producing a fiber-reinforced resin sheet according to claim 4, further comprising one or more heating rolls heated to a temperature higher than the softening point of the plastic resin.