JP3571767B2 - Method for producing tow prepreg and sheet prepreg - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a method for producing a tow prepreg used for a fiber reinforced composite material and a sheet prepreg (including a tape prepreg) comprising a plurality of tows.
[0002]
[Prior art]
The intermediate material used for the fiber-reinforced composite material is generally called a prepreg, and the reinforcing fiber tow is aligned on a hot melt film thinly coated with a resin on release paper, and a top film is placed on top of it. Alternatively, it is a general manufacturing method to stack a hot melt film from above, heat and / or press the resin to impregnate the constituent filaments of the reinforcing fiber tow with a resin, and then wind and manufacture.
As a typical example, JP-A-3-149230 and JP-B-4-5057 disclose a method of impregnating a resin by sandwiching the resin from above and below with a hot melt film.
[0003]
The method disclosed in the above-mentioned publication handles a large number of reinforcing fiber tows, and has a merit that it can be stably manufactured without contamination in the manufacturing process because it is wide and is sandwiched between protective films such as release paper.
Further, a method for producing a tow prepreg in which one tow is impregnated with a hot-melt resin is disclosed in Japanese Patent Publication No. 5-803330. In this method, a release paper or a hot-melt film is removed to produce a prepreg in tow units. Is the way.
[0004]
[Problems to be solved by the invention]
However, the prepregs manufactured by the methods disclosed in JP-A-3-149230 and JP-B-4-5057 have a very small variation in resin content when viewed in a wide direction in the width direction. When the width of the prepreg is small, the variation in the resin content is large, and when a prepreg manufactured in a wide width is cut into a narrow width and used, the variation in the resin content between the prepregs becomes too large. This is because strict control of the width of many tows is not possible, so even if the resin amount per unit area of the hot melt film is constant, there is a fluctuation in the amount of fibers per unit volume due to fluctuations in the spread of tow, The resin content per unit area after the resin impregnation (% by weight) fluctuates, and if the prepreg is used in a wide range, the resin content is offset and the accuracy is improved. For example, 1 to 5 wide prepregs are used. This is because when the slit tape is cut to a width corresponding to the degree of spread, or when about 1 to 5 tows are torn off from a wide prepreg to form a tow prepreg, the resin content greatly varies.
[0005]
Furthermore, regarding the resin impregnation speed, since the tows are placed side by side and pressed down from above and below by a protective sheet such as release paper, the movement of the filaments constituting the tow is almost impossible. Heating and pressing conditions from above and below, and if it is a thermosetting resin, it is determined in consideration of the life of the resin, and it is not necessary to simply lower the viscosity by heating, but it is a problem such as the length of the impregnation process etc. Therefore, there was a limit to the improvement of the production speed. Furthermore, when sandwiched between the hot melt films from above and below, air remains in the tow, so that impregnation failure tends to occur.
[0006]
In addition, in the method for manufacturing a tow prepreg described in Japanese Patent Publication No. 5-80330, a resin is coated in a state where the tow width is widened to form a film on the opposing surface of the tow, and the tow is impregnated by kneading. The impregnation in this method focuses on forming a resin film on the surface of the flat tow and then pushing the resin uniformly into the tow. However, this method has a problem in that a uniform film is first realized. In other words, in this method, the application amount is controlled by the gap between the doctor blade and the tow. However, since the bulk of the tow and the thickness of the tow in the width direction are not uniform and fluctuate in the longitudinal direction, even if the clearance is constant, the application thickness is constant. It is extremely difficult to control with high accuracy. Further, even when the tow is kneaded by the kneading roll, the resin moves in the thickness direction easily, but the uniformity depends on the resin coatability because the resin moves little in the lateral direction.
[0007]
The present invention solves the above-mentioned conventional problems, precisely controls the resin content using a hot melt resin, and performs efficient uniform impregnation to produce tow prepregs and sheet prepregs with high productivity. It provides a possible method.
[0008]
[Means for Solving the Problems]
The present invention provides a fixed amount of resin on at least one side of the flattened tow, and simultaneously or immediately after contacting the resin with the tow, penetrates in the thickness direction of the tow, Combining the means having the function of narrowing the tow width with the means having the action of expanding the tow width In the method for producing a tow prepreg, wherein the resin is uniformly impregnated in the tow by the lateral movement of a filament constituting the tow, and then cooled and wound, and the method for producing the tow prepreg, the flattened tow is used. Using a plurality of sheets, performing contact, permeation, uniform impregnation and cooling of the resin, and then winding each of the tows into a sheet without separating the tows. .
[0009]
The embodiments of the present invention are as follows. That is,
(1) Before the resin is quantitatively supplied to at least one side of the flattened tow, the tow is heated in advance.
(2) The tow width is increased in advance so as to be regulated at the time of contact with the resin, and the tow width is reduced at the time of contact with the resin.
(3) The amount of resin adhered to the tow is controlled by the amount of discharge of the resin discharger.
(4) Simultaneously with or immediately after the resin is brought into contact with the tow, the resin is penetrated in the thickness direction of the tow by rubbing the resin-attached surface of the tow.
(5) The lateral movement of the filament constituting the tow is further Of tow folding or tow twisting Performed by at least one means.
(6) In the step of uniformly impregnating the resin by moving the filaments constituting the tow in the lateral direction, the tow is brought into contact with a rotating body rotating at a peripheral speed lower than the running speed of the tow.
(7) In the cooling step, the cross-sectional shape of the tow is controlled by reducing the width of the tow on the cooling roll and simultaneously compressing the tow.
(8) Immediately before winding, narrow the tow width and simultaneously compress it to control the cross-sectional shape.
(9) After uniformly impregnating the resin, powder is attached to the tow.
(10) After uniformly impregnating the resin, the separator carrier is supported on one surface of the tow.
(11) Using a plurality of flattened tows, after performing contact, permeation, uniform impregnation and cooling of the resin, each tow is individually wound.
[0010]
The tow in the present invention is a bundle of reinforcing long fibers (filaments) composed of inorganic fibers, organic fibers, metal fibers, or a mixture thereof.
Inorganic fibers such as carbon fiber, graphite fiber, silicon carbide fiber, alumina fiber, tungsten carbide fiber, boron fiber, glass fiber, etc., and organic fibers such as aramid fiber, high density polyethylene fiber, and other general organic fibers such as nylon and polyester Etc. are preferably used.
As the metal fiber, stainless steel, iron, or the like can be used as long as it has a mobility in a filament form.
The diameter of the filament is preferably from 0.1 μm to 100 μm. If it is less than 0.1 μm, there is a problem that the strength of the filament is small and the filament may be cut or fuzzed when the filament is moved laterally. If it is more than 100 μm, it becomes too hard and inferior in flexibility, which is not preferable.
[0011]
As the resin, a thermosetting resin and a thermoplastic resin used as a matrix resin of the fiber-reinforced composite material are used. For example, as the thermosetting resin, epoxy resin, phenol resin, vinyl ester resin, epoxy acrylate resin, urethane acrylate Resins, phenoxy resins, alkyd resins, urethane resins, etc., and as the thermoplastic resin, super engineering plastics such as PEEK, PEI, polyarylate, polysulfone, engineering plastics such as nylon, polyester, ABS, and the like. General-purpose plastics such as acrylic resin, polyethylene resin and polypropylene resin can be used.
[0012]
The property required for these resins is that they have fluidity at the temperature at the time of impregnation. The range of viscosity as a measure of fluidity is preferably from 1 CPS (centipoise) to 1,000,000 CPS, more preferably from 1 CPS to 10,000 CPS. The reason is that, in order to facilitate the movement of the filament and the accompanying resin movement by the resin impregnation action by the filament movement described below, at least the filament mobility must be high, and for that purpose, the viscosity of the resin is reduced. This is because it is necessary to reduce the resistance of the filament movement.
[0013]
At a viscosity level less than 1 CPS of resin is scarcely present, and at viscosities above 1 million CPS, filament movement and consequent resin movement are almost impossible. The presence or absence of an additive such as a filler is not a problem as long as the resin has fluidity at the time of impregnation.
[0014]
It is desirable that the tow be flat to increase the contact area with the resin. It is also important to make the tow width constant so as to keep the contact area with the resin supplied in a constant amount constant. In general, the reinforcing fiber tow does not have a constant width, so it is necessary to increase the width. Examples of the method of widening include a method of rubbing with a cylindrical bar, a method of applying vibration, and a method of crushing. In the present invention, the tow may be expanded in-line or off-line beyond the tow width when the resin comes into contact with the tow. Commercially available taped tows are considered offline widened tows. The width of the widened tow is usually not stabilized, and its spread varies. Therefore, in order to stabilize the contact area with the resin at the time of the resin contact, it is effective to narrow the tow width immediately before or at the time of the resin contact to stabilize the area. As an example of the method, a method of providing a groove of a predetermined width at the resin discharge port or a position immediately before the resin discharge port and running the tow in the groove to reduce the tow width is preferable.
[0015]
Preheating the tow means that the tow temperature is raised in advance so that the resin temperature does not decrease when the resin permeates into the tow after contact with the resin. If the temperature of the tow is set to be equal to or higher than the resin temperature before the contact by the preheating, the tow temperature after the contact between the tow and the resin does not become lower than the resin temperature before the contact. As the preheating method, any of contact heating with a heating element, and non-contact heating methods such as electric heating, dielectric heating, infrared heating, and atmospheric heating can be used.
[0016]
As a method of supplying a fixed amount of resin to the tow, it is preferable to use a molten resin discharger such as a plunger discharger, a gear pump discharger, and an extruder. Particularly, it is preferable to use an ultra-precision gear pump or an extruder for the quantitative supply accuracy. Above ideal. When the resin life after mixing of the resins becomes a problem in the case of a thermosetting resin, it is more ideal if the curing agent and the main agent are separately extruded and supplied while being mixed by a static mixer or the like. What is necessary at the time of attachment is that the resin has a low viscosity and is easily attached to the tow.
There is a method of controlling the resin supply amount by squeezing the resin with a die or the like by excessively adding the resin. However, if the line speed is increased, the yarn is liable to be broken due to friction between the die and the tow.
Also, as described in Japanese Patent Publication No. 5-80330, there is a method of controlling the clearance with a doctor blade or the like. However, if the coating is performed on a substrate that does not penetrate the resin, the resin may penetrate the substrate. Since there is no toe, the amount of adhesion can be controlled by the coating thickness, but it is difficult to control precisely because the tow has permeation, and if the tow passes through the clearance, it can easily cause thread breakage and clogging.
[0017]
The content of the resin to be impregnated into the tow is preferably from 10% by weight to 80% by weight. If it is less than 10% by weight, it is difficult to uniformly impregnate it, and if it exceeds 80% by weight, problems occur in the mechanical properties of the composite material molded product. In order to effectively exhibit the performance of the mechanical properties, it is ideal that the content is 30% by weight or more and 50% by weight or less.
[0018]
In the present invention, it is important to allow the resin to penetrate the tow in the thickness direction of the tow at the same time as or immediately after the resin is brought into contact with the tow, from the viewpoint of allowing the resin to be quantitatively supplied to permeate into the tow without delay. In this point, the method is remarkably different from the method of Japanese Patent Publication No. Hei 5-80330, in which a resin film is simply formed on both surfaces of the tow. As a specific method of penetrating the resin, it is a good method to quickly rub the toe surface side with which the resin has contacted. Here, rubbing means rubbing the tow on a rubbing body such as an arc or an edge.
[0019]
Since the tow is pressed against the rubbing body at the time of rubbing, a resin pressing force inevitably acts in the thickness direction of the tow, and as a result, the resin permeates into the tow. Since the tow is pressed against the scraping body, there is no gap between the scraping body and the tow. The contact angle with the scraping body is desirably 1 ° or more and 90 ° or less. If it is less than 1 °, the effect of resin permeation is small, and if it exceeds 90 °, the tension due to the resistance due to abrasion becomes too large, and there is a possibility that the yarn breaks. When abrupt pressing force is generated by abrasion, the penetration of the resin into the tow becomes uneven, but here the purpose is not to impregnate the resin uniformly, but to ensure the adhesion of the resin The focus is on. Therefore, uniformization of the resin impregnation is an important issue in the next impregnation step.
[0020]
The lateral movement of the filament in the resin impregnation step of the present invention is performed by applying an external force to the tow to move the filament constituting the tow in the lateral direction (the direction perpendicular to the longitudinal direction), and changing the relative position between the filaments and the resin. By increasing the chance of contact with the filament, a more uniform impregnation effect than the impregnation effect due to simple pressurization or capillary action is achieved. Specifically, fold the toe, Combining toe width expansion and toe width reduction Or at least one means such as twisting the tow. According to the twisting means, the action of pushing the resin out of the tow is also added.
[0021]
In these means, the folding means and the twisting means tend to narrow the tow width similarly to the width reducing means. When the means for reducing the tow width and the means for expanding the tow width are used in combination, the effect of uniform impregnation is enhanced.
Note that twisting may be performed at the time of resin impregnation, and if untwisted state is required after impregnation, untwisting may be performed after impregnation. In the case of false twist, it is not necessary to perform untwisting, and it is desirable when a tow without twist is required. If abrasion is applied at the same time as or immediately after twisting, the tow width tends to widen, and the uniformity of impregnation increases due to the movement of the resin in the thickness direction.
[0022]
In the uniform impregnation of the lateral movement of the filament, contacting the tow with a rotating body rotating at a peripheral speed lower than the running speed of the tow and scraping the tow is useful for fuzz accumulation, roll cleaning, and the like. If rubbed, the tow does not become entangled with the surface of the rotating body, and the rotating body is rubbed and rotated by the tow, so that the surface that comes into contact with the tow is always cleaned, improving the manufacturing environment. Is also useful. It is sufficient that the peripheral speed of the rotating body is lower than the traveling speed of the tow, and the rotation may be in a direction opposite to the traveling direction of the tow.
[0023]
The tow uniformly impregnated with the resin has a low resin viscosity due to heating and cannot be wound immediately. Therefore, it is necessary to cool the tow to improve the operability. The cooling temperature may be a temperature at which the resin is peeled off without attaching to the surface of the cooling body, for example, the cooling roll, and it is necessary to determine the cooling temperature according to the resin system. For example, a resin system used for ordinary prepregs has some stickiness at room temperature, so it is preferable to lower the tow temperature within a range of 0 ° C to 30 ° C.
[0024]
In the present invention, the width of the tow uniformly impregnated with the resin can be reduced by a grooved roll or a roll provided with a clearance, and at the same time, the tow can be compressed to control the cross-sectional shape. The control position is preferably at the time of cooling after uniform impregnation or immediately before winding on a bobbin. If the tow is too cold just before winding on the bobbin and it is difficult to shape the cross-sectional shape, the cross-sectional shape may be regulated after heating to a temperature at which shaping is possible.
Further, the cross-sectional shape control can be performed off-line after winding on the bobbin, and re-winding.
[0025]
When pulling out the tow from the bobbin, the unwinding property of the tow is important. When a resin having a high viscosity at room temperature is used, adhesion between the tows does not easily occur and there is no problem in unwinding, but if the viscosity is low, unwinding is impossible. As a method for solving the problem, there is a method in which powder is adhered to a surface to eliminate stickiness of the surface. As the type of powder, various organic and inorganic powders can be used. As the organic substance, for example, a thermosetting resin or a thermoplastic resin can be used. Specifically, the thermosetting resin is preferably an epoxy resin, a phenol resin or the like, and the resin may be cured or uncured. As the thermoplastic resin, nylon, polypropylene, polyethylene and the like can be used. In addition, common fillers such as talc and silica can be used as the inorganic substance.
There are various methods for attaching the powder, but generally, a method of passing a tow through a fluidized bed or a method of spraying the tow is preferred.
The position where the powder adheres to the tow may be any position after the resin is uniformly impregnated.
As long as the tow loses adhesiveness and the unwinding property from the bobbin is improved, there is no limitation on the type, particle diameter, and amount of the powder.
[0026]
As a method for improving the unwinding property of the tow from the bobbin, a method of supporting a separator carrier on one side of the tow is also suitably used.
Although various carriers can be used, an inexpensive film-shaped carrier having good releasability from the tow and reducing material costs is preferable. As a typical example, a polyethylene film and a polypropylene film are suitable. Release paper may be used, but it is expensive. The width of the film may be about the width of the toe, and if it is held on one side, the unwinding after winding on a bobbin is also good.
The supporting position may be any position after the resin is uniformly impregnated as in the case of the powder adhesion. However, when controlling the cross-sectional shape, it is desirable after the shape control.
[0027]
In the case where a plurality of tow prepregs are individually wound and manufactured, the tows may be individually wound after contacting, permeating, uniformly impregnating, and cooling the plurality of tows. The uniform impregnation of the resin may be carried out collectively with a plurality of tows, or may be carried out separately from each tow. The tow can be individually wound if it is separated when wound by a winder.
Also, when manufacturing a sheet-shaped prepreg from a plurality of tows, using a plurality of flat tows, after contacting, infiltrating, uniformly impregnating and cooling the resin, without separating each tow What is necessary is just to wind up in a sheet form. In this case as well, the uniform impregnation of the resin may be performed by a plurality of tows collectively or by separating each tow separately.
[0028]
If it is necessary to further twist the produced prepreg, a twisting step can be appropriately performed before and after cooling.
Although the line constant speed control may be performed in principle anywhere, it is desirable to perform it after cooling the tow or before adhering the resin.
When winding in a tow state, a commercially available winder can be used as the winder.
[0029]
FIG. 1 is a side view showing an example of a basic process for manufacturing a tow prepreg. In FIG. 1, a tow 2 wound on a bobbin is pulled out of a creel 1, and the pulled out tow 2 is passed through a rubbing widening roll 3 and then supplied while controlling a traveling speed by a Nelson roll 4. The resin is extruded by a resin discharge machine 5 containing a resin heating tank and a gear pump, and supplied to a discharge port 7 via a heating pipe 6. At this time, the widened tow 2 is passed through a groove (not shown) provided in the discharge port 7 to make the width narrower and to make the width constant and to contact the supplied resin. Thereafter, the resin is made to penetrate into the tow 2 on the resin-penetrating rubbing roll 8. In order to reduce the tow width, and to prevent the resin from overflowing during resin penetration due to resin adhesion or rubbing, the tow passage band of the resin penetration rubbing roll 8 is preferably formed in a groove shape. Thereafter, the tow 2 is uniformly impregnated in the filament laterally moving impregnating section 9, and the uniformly impregnated tow 2 is cooled by the cooling roll 10. The cooled tow 2 is taken up by a torque motor roll 12 with a constant torque, and finally wound up on a bobbin by a winder 14.
[0030]
FIG. 2 is a side view showing an example of a means for performing the lateral movement of the filament constituting the tow by using both enlargement and reduction of the tow width. In FIG. 2, reference numeral 15 denotes a roll for enlarging the tow width. Reference numeral 16 denotes a roll for reducing the tow width, and the tow width can be reduced by inclining the roll.
[0031]
FIG. 3 is a side view showing an example of a means for performing the lateral movement of the filament constituting the tow by using both the twisting of the tow and the enlargement of the tow width. In FIG. ing.
[0032]
FIG. 4 is a side view showing an example of means for simultaneously moving the filament constituting the tow in the lateral direction by folding the tow and enlarging the tow width. In the drawing, the tow 2 is gradually folded by the folding guide 19. And is completely folded by the vertically standing roll pair 18.
[0033]
FIG. 5 is a front view showing an example of means for controlling the cross-sectional shape of the tow by simultaneously compressing and reducing the tow width on the cooling roll. In FIG. The tongue 2 is fitted with an appropriate gap, and the tow 2 is passed between the protrusions, thereby narrowing the tow width and simultaneously compressing the tow 2 to control the cross-sectional shape of the tow 2.
[0034]
【Example】
Hereinafter, the present invention will be described more specifically with reference to examples.
[0035]
[Example 1]
In the manufacturing process shown in FIG. 1, a tow prepreg was manufactured using two units of the apparatus shown in FIG. 2 as a filament lateral moving means. Using a single carbon fiber TR30G tow manufactured by Graphite Co. as a tow, the tow 2 is widened to a width of 5 mm or more with a rubbing widening roll 3, and is narrowed to a width of 4 mm with a groove at a resin discharge port 7 to form a resin on one surface of the tow 2. The resin was supplied from the discharge port 7 and brought into contact therewith, and was rubbed with the rubbing roll 8 for resin permeation to permeate the resin into the tow 2. The resin used was a resin composition in which Epicoat 1001 and 834 manufactured by Yuka Shell Eposiki were mixed at a ratio of 50/50, and 4 parts of dicyandiamide was mixed with the mixture. The resin was kept at 65 ° C. in a tank, and was discharged at 120 ° C. from a discharge port 7 through a heating hose 6 from a gear pump. In the vicinity of the discharge port 7, there is no overflow of the resin and no stagnation of the resin when the resin comes into contact with the tow and penetrates into the tow, and the resin supplied from the resin discharger 5 adheres to the tow without stagnation. confirmed.
[0036]
Thereafter, the resin was uniformly impregnated in the tow by passing between the tow width expanding and reducing rolls (fixed without rotating) in FIG. 2 to move the filaments constituting the tow in the lateral direction. Although the tow temperature after resin contact and infiltration was 70 ° C, the tow temperature was raised to 120 ° C on the first roll, and the resin temperature was maintained at 120 ° C on the subsequent rolls, at which time the viscosity was about 500 CPS. Was. After the width of the tow was increased to about 5 mm by the last roll, the tow was cooled by the next cooling roll, taken up by the torque motor roll 12 at a constant torque, and then wound by the winder 14.
The production speed of the tow prepreg was 100 m / min, the impregnation state was good, and the resin content was within the range of 35% ± 1%, and the precision was high.
[0037]
[Example 2]
A tow prepreg was manufactured in the same manner as in Example 1 except that the apparatus shown in FIG. 3 was used instead of the apparatus shown in FIG. In this case, the number of twists by the twisting tool 17 was 10 T / M.
The resin impregnation state of the tow prepreg was good, and the precision of the resin content was high as in Example 1.
[0038]
[Example 3]
A tow prepreg was manufactured in the same manner as in Example 1 except that the apparatus shown in FIG. 4 was used instead of the apparatus shown in FIG.
The resin impregnation state of the tow prepreg was good, and the precision of the resin content was high as in Example 1.
[0039]
[Example 4]
In the same process as the manufacturing process of Example 1, five tows were used, each tow was pulled out from the creel, and each was widened to 5 mm or more by a rubbing widening roll. After that, the resin was supplied and brought into contact with one side of the tow from the resin discharge port, and was rubbed with a rubbing roll for resin permeation so that the resin permeated into the tow. Next, the tows were separated one by one, and the filaments constituting the tow were moved laterally by passing between the tow width expanding and reducing rolls, so that the resin was uniformly impregnated in the tow. Then, after cooling with a cooling roll, it was individually wound up with five winders.
The resin impregnated state of each of the obtained tow prepregs was good, and the precision of the resin content was high as in Example 1.
[0040]
[Example 5]
A tow prepreg was manufactured in the same manner as in Example 1 except that a heating roll was installed in front of the resin discharge port to preheat the tow.
The tow was preheated to 130 ° C. by contact with a heating roll. Although the temperature of the resin discharged from the discharge port was 110 ° C., the tow temperature after contacting and permeating the resin was about 120 ° C. After the resin was uniformly impregnated in the tow, it was cooled and wound around a bobbin. In Example 1, since the tow temperature after resin contact and permeation was not preheated, it was necessary to raise the tow temperature with the first filament laterally moving roll. The heating efficiency of the tow was improved by raising.
The resin impregnated state of each of the obtained tow prepregs was good, and the precision of the resin content was high as in Example 1.
[0041]
[Example 6]
A tow prepreg was manufactured in the same manner as in Example 1, except that the tow width enlarging and reducing rolls were rotated at a peripheral speed of about 2.5 m / min. In Example 1, fluff was slightly deposited on the rear portion of the tow width expanding and reducing rolls. However, in this example, no fluff was deposited and the workability was good.
[0042]
[Example 7]
In the first embodiment, instead of the cooling roll 10, the tow width is reduced and compressed by using the cooling roll 20 having the concave portion and the compression roll 23 having the convex portion as shown in FIG. A tow prepreg having a rectangular cross section was manufactured.
[0043]
Example 8
In Example 1, the tow is heated using a heating roll immediately before winding by a winder, and subsequently, the tow width is reduced using a cooling roll 20 having a concave portion and a compression roll 23 having a convex portion shown in FIG. It was compressed and then wound up on a winder to produce a tow prepreg having a rectangular cross section with a width of 4 mm.
[0044]
[Example 9]
In Example 1, the resin was uniformly impregnated into the filaments of the tow, and then a fluidized bed of the powder was installed so that the powder adhered to the tow. Silica fine particles having a particle size of about 20 μm were used as the powder. The amount of powder adhered was about 2% by weight, and the obtained tow prepreg had good unwinding properties from the bobbin.
[0045]
[Example 10]
In Example 1, after cooling the tow, a polypropylene film having a width of 5 mm was supported on one surface of the tow and wound around a winder. The unwinding property of the obtained tow prepreg from the bobbin was good.
[0046]
[Example 11]
In Example 7, 10 tows were used, each tow was formed into a tow prepreg having a rectangular cross section having a width of 4 mm, and then heated with a heating roll. The sheet was arranged in the concave portion and compressed by the convex portion of the compression roll to form a 40 mm width sheet-shaped prepreg.
The resin-impregnated state of the obtained sheet-like prepreg was good, and the precision of the resin content was as high as that of the tow prepreg of Example 7.
[0047]
【The invention's effect】
Advantageous Effects of Invention According to the present invention, an excellent effect that tow prepregs and sheet prepregs can be produced with high productivity by precisely controlling the resin content using a hot melt resin and performing efficient uniform impregnation. Play.
[Brief description of the drawings]
FIG. 1 is a side view showing an example of a basic tow prepreg manufacturing process of the present invention.
FIG. 2 is a side view showing an example of a means for performing a lateral movement of a filament constituting the tow by using both enlargement and reduction of the tow width.
FIG. 3 is a side view showing an example of a means for performing a lateral movement of a filament constituting the tow by using both twisting of the tow and expansion of the tow width.
FIG. 4 is a side view showing an example of a means for performing a lateral movement of a filament constituting the tow by using both folding of the tow and enlargement of the tow width.
FIG. 5 is a side view showing an example of means for controlling the cross-sectional shape of the tow by compressing and simultaneously reducing the tow width on the cooling roll.
[Explanation of symbols]
1 Creel
2 toe
3 Abrasion widening roll
4 Nelson Roll
5 Resin discharging machine
6 heating tubes
7 Discharge port
8 Rubbing roll for resin penetration
9 Roller impregnated with resin moving laterally in filament
10 Cooling roll
11 Guide roll
12 Torque motor roll
13 Guide roll
14 Winder
15 Toe width enlargement roll
16 Toe width reduction roll
17 Twisting tool
18 vertical roll
19 Folding guide
20 Cooling roll
21 recess
22 Compression roll
23 convex

Claims (13)

A fixed amount of resin is supplied to at least one side of the flattened tow, and at the same time or immediately after the resin is brought into contact with the tow, the resin is penetrated in the thickness direction of the tow, and a means having an action of narrowing the tow width and an action of expanding the tow width are provided. A method for producing a tow prepreg, characterized by uniformly impregnating the resin in the tow by laterally moving a filament constituting the tow in combination with a means having the tow, and then cooling and winding the tow. As the lateral movement of the filaments constituting the tow, furthermore, by folding the tow or twisting the tow, the resin is uniformly impregnated in the tow by the lateral movement of the filament constituting the tow, and then cooled and wound. The method for producing a tow prepreg according to claim 1, wherein The method for producing a tow prepreg according to claim 1 or 2, wherein the tow is heated in advance before a fixed amount of resin is supplied to at least one surface of the flattened tow. The method for producing a tow prepreg according to any one of claims 1 to 3, wherein the tow width is increased in advance so as to be regulated at the time of contact with the resin, and the tow width is reduced to a predetermined width at the time of contact with the resin. The method for producing a tow prepreg according to any one of claims 1 to 4, wherein a resin adhesion amount of the tow is controlled by a discharge amount of the resin discharger. The method for producing a tow prepreg according to any one of claims 1 to 5, wherein the resin is made to penetrate in the thickness direction of the tow by rubbing the resin-attached surface of the tow simultaneously with or immediately after the resin is brought into contact with the tow. . The method for producing a tow prepreg according to any one of claims 1 to 6 , wherein the tow is brought into contact with a rotating body rotating at a peripheral speed lower than the running speed of the tow in the resin uniform impregnation step by laterally moving a filament constituting the tow. . The method for producing a tow prepreg according to any one of claims 1 to 7 , wherein in the cooling step, the cross-sectional shape of the tow is controlled by simultaneously reducing the tow width on a cooling roll and compressing the tow. The method for producing a tow prepreg according to any one of claims 1 to 8, wherein the cross-sectional shape is controlled by reducing the tow width and simultaneously compressing the tow just before winding. The method for producing a prepreg according to any one of claims 1 to 9 , wherein a powder is adhered to the tow after uniformly impregnating the resin. The method for producing a tow prepreg according to any one of claims 1 to 10 , wherein the separator carrier is supported on one side of the tow after uniformly impregnating the resin. The method for producing a tow prepreg according to any one of claims 1 to 11 , wherein the plurality of flat tows are used to perform contact, permeation, uniform impregnation and cooling of the resin, and then individually wind each tow. The method for producing a tow prepreg according to any one of claims 1 to 12, wherein a plurality of flat tows are used, and after contact, permeation, uniform impregnation and cooling of the resin are performed, each tow is not separated. A method for producing a sheet-shaped prepreg, which is wound into a sheet.

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