JPH02297425A - Fiber reinforced plastic core stock and core material, and continuous manufacture thereof - Google Patents

Abstract

PURPOSE:To manufacture the FRP core material at a low cost by a method wherein resin sheet, which is produced by putting another film on a film, onto the surface of which thermosetting resin liquid is applied so as to sprinkle or place glass fibers over or on said surface, fixing the films together by pressure and deaerating the resultant films, is heated and wound round a large number of round bars in order to be formed in a continuous S-shape and set. CONSTITUTION:Cut glass fibers 5 are sprinkled over the surface of running carrier film 1, onto which unsaturated polyester resin liquid 2 is applied. Further, the same film 9 is fed on said film 1 so as to pinch said sprinkled surface of the glass fibers from both sides by the carrier films 1 and 9 for running, fixing by pressure and deaerating the resultant films in order to form in a continuous S-shape by being wound round heated round bars 22 and 23 and set. Thus, FRP core material can be produced at a very low cost.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention uses FRP, a plastic molded by mixing glass fiber 11 as a reinforcing phase in polyester resin, epoxy resin, or phenol resin, as a material. , relates to a method for manufacturing a honeycomb core core material and a core material from this material, and includes a core mill manufactured by this method.

[Conventional technology and its problems] Regarding manufacturing a plastic honeycomb core,
For example, as disclosed in Japanese Patent Application Laid-Open No. 56-98159 or US Pat. This method is intended for plastic plastics, and there are almost no known methods for thermosetting resins such as FRP. In actual products, products using FRP for the core are only slightly used in the aircraft industry, with the exception of the product developed by the present inventor. If the material resin is thermosetting, it is not easy to mold and hold the specified shape as a core, and therefore it is not possible to manufacture it in a laboratory. However, there is still no known method suitable for mass production.

As is well known, flat plates and corrugated plates made of FRP already have a long technological history, and it is widely known that flat plates and corrugated plates made of FRP exhibit excellent characteristics in terms of performance. Recognized. Therefore, if it were possible to manufacture a sandwich panel using FRP as the core, it would have a very high utility value, and there was no objection to this, but as a practical matter, it was never realized.

By the way, although it was possible to create extremely thin sheets of FRP and process them into a honeycomb shape in a laboratory, there were too many unresolved problems to manufacture them on an economical industrial scale. is the current situation.

That is, generally, the core of a sandwich panel is manufactured from a sheet-like material such as aluminum foil, paper, or vinyl chloride film. It is not impossible to make a thin sheet of FRP in advance and process it into a core.

However, step-1--this is twice the effort and causes the following problems. In other words, the heat curing process requires a very long distance as it is run on a flat sheet, and the hardened flat sheet must be bent and processed into a honeycomb shape.
Even when processing into a circular shape (roll core shape) as in the case of the present invention, not only is heating required again, but the processing itself is not easy in the first place.

[Means for Solving the Problems] Here, the present invention continuously unrolls a flexible carrier film, and coats the surface of this film with an uncured thermosetting resin such as an unsaturated polyester resin. After uniformly applying a resin solution, after scattering or placing glass fibers as profiteers on the surface of the coating solution, another flexible carrier film is layered on top of it and run,
The profiteering agent and the coating liquid are pressed and degassed from below to form a thin resin sheet, and this sheet is then wrapped together with the carrier film around a number of heated round rods so that the whole becomes a continuous S-shape. After molding and hardening in that shape, the round rod is removed, and the films arranged on both sides of the sheet are separated by 11 degrees.
This makes it possible to solve the problems of the conventional method described above. By the way, as mentioned above, continuous S
Of course, the material for the core which has been molded and hardened into a character shape is cut to an appropriate length and then laminated and bonded to form an FRP core +4 having the required dimensions. Furthermore, in the present invention, after the carrier film has been peeled off, the molded sheet is reheated to a temperature close to that at the time of molding, so that the continuous figure 8 shapes are brought into contact with each other to continuously correct the molded product. It also includes methods that are carried out on a regular basis.

Furthermore, the glass fiber as the group A may be either one cut into short pieces or a glass cloth. Furthermore, when a thin and coarse glass cloth is used, the crossed fibers may be used. Since missing portions of the resin can be formed between the resin sheet and the fibers, pinholes can be uniformly formed over the entire surface of the resin sheet after molding. In addition, when a glass chop is used as a profiteer, the difference between the amount of spraying of the glass chop and the amount of resin applied to the surface of the carrier film is
When the glass fiber distribution ratio is higher than the amount of resin applied, uniform pinholes can be formed in the entire resin shift area after molding.

As described above, the present invention provides a method of molding an amorphous liquid resin and glass fiber into a required shape before curing, which is an extremely efficient method. Moreover, since a molded sheet with 8 consecutive characters can be obtained at once, compared to processing it from a flat plate, it is about 1.
This has the advantage that 15 distance spaces are sufficient. Furthermore, although heating is required to cure the resin, the length of the furnace used for heating is shorter than that required for making flat plates, so efficiency can be greatly improved.

By the way, apart from the case where pinholes are actively formed in the resin sheet after molding, when forming a sheet as thin as possible without forming pinholes, the amount of resin is 0.2 to 0. 4 kg/r+f, glass fiber amount 0.
A range of 1 to 0.2 Kg/m2' is acceptable.

[Embodiment] Hereinafter, the present invention will be specifically explained based on the illustrated apparatus.

In FIG. 1, numeral 1 is a gear rear film,
Regardless of whether it is inorganic or organic, any heat-resistant and flexible film can be used, including paper, metal, thermoplastic, and thermosetting resin films.

Thus, winding of the carrier film 1. The strip-shaped film 1 let out from a is immersed in a storage tank 2 filled with a solution of an uncured thermosetting resin and brought into contact with a rotating application roll 3 to coat the surface of the running film 1 with -
For example, a resin solution 4 of unsaturated polyester is uniformly applied to a predetermined amount.

Next, on top of the resin liquid, glass fibers 5 cut short (for example) are uniformly scattered, or plain-woven glass fibers are continuously placed.
Reference numeral 6 is a winding device for the long glass fibers, 7 is a cutting device for cutting the long fibers into short pieces, and 8 is a hopper. The resin liquid 4 on which the glass fibers 5 are scattered or disposed travels together with the carrier film 1 to the right as shown in the figure, and then a carrier film 9 having the same structure as described above is further rolled up. 9a and laminated so as to cover both sides of the resin liquid. In this way, the resin liquid and the glass fibers are sandwiched between the carrier films 1 and 9 from the upper and lower sides (this state is indicated by the symbol 0). In this state, nip roll 1
1.11, the resin liquid is compressed and degassed, and then introduced into the next molding device 12. Hereinafter, an example of the molding apparatus will be specifically explained based on FIG. 1. In the figure, a pair of upper and lower endless chinos 20 and 21 are suspended symmetrically by 1", and a large number of round bars 22,
23 is attached rotatably. However, the Cheno 20,
When 21 is guided between the guide plates 24 and 25 by the drive of a chain poil (not shown), the round bars 22 and 23, which are attached to the upper and lower chains, are moved from above and below. They operate in a state where they are engaged with each other alternately. In addition, as shown by the reference numeral 26 in the figure, each of the above-mentioned devices is housed in a single housing,
In addition, an infrared lamp 27 is provided inside the housing 26, as an example.
The round rods 22 and 23 are heated so that they can be heated.

By the way, the molding round bar 23 in the molding device 12.
The heating temperature in step 24 varies depending on the curing temperature of the thermosetting resin used, but it is preferably heated to about 100°C, and the above-mentioned resin liquid layer is applied to this heated round bar from both sides of the carrier film. With the carrier film applied, each carrier film (see reference numeral 10) is wound around a round bar and brought into contact with it to form a continuous S-shape. The layered resin liquid indicated by the reference numeral 10 hardens while the round rods 22 and 23 move while being engaged with each other, and becomes a very thin molded sheet of FRP.

The state is as shown in FIG. 2, and the continuous S-shaped molded sheet 13 that has hardened while holding the round bar is
The laminated carrier films 1 and 9 are formed into an S-shape, but when the round bar 22 or 23 is removed from this state, the entire film and sheet form a U-shape as shown in FIG. Transform to open. That is, the round bars 22, 24 are removed from the sheet after molding and are discharged from the molding apparatus. Incidentally, the molded sheet 13 from which the round bars have been removed as described above is elastic, so although it is not perfect, it returns to its original shape and maintains the continuous figure eight shape.

As mentioned above, in the present invention, the resin liquid is coated and formed in a layer on a carrier film, and then heated and cured at a temperature of about 100°C, for example. Regarding temperature settings, the following points need to be considered.

In other words, when a relatively thin FRP sheet is brought into direct contact with a hot round rod, the temperature transfers rapidly, and the polyester resin experiences an extreme drop in viscosity due to the rapid temperature rise, and the viscosity of the polyester resin decreases when it is wrapped around the rod. Due to the contact pressure, there is a risk that the resin or glass fibers may protrude from both edges of the film.

Therefore, in order to prevent this viscosity reduction, when implementing
A filler such as Erosil may be added.

Note that if the viscosity at room temperature becomes too high, impregnation into glass fibers and defoaming will become difficult, so this point also needs to be taken into consideration.

In short, we added a filler to prevent the resin liquid from flowing out from the edges of the carrier film and at the same time speed up the curing speed. It is most appropriate to do so. In addition, when the round bars combined in a continuous S-shape are advanced together with the FRP sheet and maintained in a heated state, the polyester resin bitten by the round bars will change depending on the type and amount of the curing agent added. It will harden in about 2 minutes, but it will harden in about 2 minutes. After curing is completed, the round bar is removed from the molded sheet as described above, returned to its original position, and a new sheet is wrapped around it again for curing. will be carried out. As mentioned above, in the present invention, after the resin sheet is molded and hardened, the round rod used for molding is removed from the sheet, but even after the molded resin sheet is hardened, it still has a 100% ℃, so it is in a somewhat softened state, so there is no problem in drawing it out. Note that the shape of the sheet after the round rod is pulled out in a heated state does not return to a perfect S-shape, and a gap as shown by symbol A in FIG. 2 is generated. On the other hand, when the sheet and round bar are completely cooled and the round bar is removed at room temperature, the elasticity of FRP completely restores the original shape as shown in Figure 4.

However, even if the shape is slightly distorted when the round bar is removed while being heated, it can be corrected as described below.

As shown in FIG. 1, the sheet formed in the above manner is sent to a later stage via a conveyor 1.4, and is removed by a peeling jig 15 installed at the end of the conveyor. Only the carrier film, which has become , is peeled off from both sides of the molded sheet (see FIG. 3). Note that each peeled film is wound up in 1. a and 9b
It is wound up as.

That is, after being demolded from the round bars 22 and 23, the FRP is coated with carrier films 1 and 9 on both sides.
As the sheet 13 progresses, a step for peeling off this film is provided at a subsequent stage of the molding device. in this case,
The sheet 13 is still at a high temperature and is very difficult to peel off in this state. This is because FRP sheets are thin and softened, so they deform with the slightest force.
Therefore, it is better to cool it down to some extent before peeling it off. In addition, when peeling a relatively thin continuous S-shaped molded sheet, the X location in Figure 3 is easy to peel off by 180° peeling, but the y location is almost parallel to the molded sheet, so the molded product is deformed. Do not peel until the angle is close to 90°. Furthermore, even if the peeled film on both sides is wound up at a constant speed, the strength of the peeling force will intermittently change, and this will occur on both sides, which may cause severe vibrations. In order to prevent such problems, it is possible to use a peeling jig 15 as shown.

By the way, in Example 1, a step was added in which the molded sheet 13 after the carrier film was peeled off as described above was guided to the heater J6, where it was reheated at a temperature close to that of molding. .

When such an operation is applied, the molded resin sheet is corrected to a continuous S-shape without distortion due to a kind of shape memory effect, that is, when adjacent S-shapes are in contact with each other, Preferably, this heating step is added. The continuous S-shaped molded sheet 13 thus obtained is cut into required lengths by a cutting device J7 (see FIG. 4), and is used as a material for a so-called core.

The molded sheet 13, which is the core material made only of FRP, is cut into a certain length as described in 1 above to produce a product as shown in Fig. 4, which is then coated with adhesive and laminated. After completion of adhesion by pressing, heating and curing, a laminated product as shown in FIG. 5 is obtained. Then, if this is cut using a band saw or the like to maintain an appropriate height H, an FRP core as shown in FIG. 6 will be completed.

Example 1 A polyester film (30μ thick) with a film width of 500 mm was run as a carrier film at a speed of 10 m/mJn, and an unsaturated polyester resin liquid was added to it at 0.
．． A glass fiber strand cut to a length of 30 mm was coated on the coated surface at a weight of 20 kg/m2. It was sprayed at a rate of kg/ryl'. On top of that, the same film as described above is further supplied, and the above-mentioned glass fiber distribution surface is sandwiched between upper and lower surfaces by carrier films and run, and is pressed with a roller to defoam. It was heated to 100°C and wound around a round bar with a diameter of 8.5 mm and a length of 520 mm in a continuous S-shape, and was molded and cured. The connecting length of the round rods was 2 m, and the opening of the figure 8 portion of the FRP sheet after peeling off the carrier film was about 3 mm.

This was heated to 100°C and cooled to correct the shape after molding, and the molding speed at this time was 2 m/m], n.

Further, the apparent density when the FRP sheets obtained in this manner were laminated and bonded was 100 kg/m3.

This block was cut to a thickness of 20 mm and the compressive strength was measured to be 80 kg/cm2.

Example 2 A core material was obtained in the same manner as above except that the diameter of the round bar was 14 mm. The amount of resin was 0.3 kg/rd, and the amount of glass fiber was 0.15 kg/m2. Further, the apparent density of the product was 120 kg/m''. The compressive strength at this time was 100 kg/cm2.

Example 3 ” The diameter of the round bar was cut to 231 using the same method as in 1.

The amount of resin is 0.4kg/m2', the amount of glass fiber is 0.2k
The apparent density of the product when g/n-r is 80 kg
/y11”.The compressive strength at this time was 80 kg
/cm2.

Example 4 Same method as Example 2, only glass fiber 144g/rd
Made of plain woven glass cloth. In addition, this cross is 25m
m width, and there were 19 warp threads and 19 weft threads each. In addition, the apparent density was 1.20 kg/m'' and the compressive strength was 105 kg/cm2.
Pin poles of about 1 mmφ were uniformly generated over the entire surface of the molded sheet.

As described in detail below, according to the present invention, the thickness of the FRP sheet can be controlled by the amount of resin liquid applied to the carrier film 7.

Therefore, it is possible to actively create pinholes over the entire surface of the molded sheet, rather than using peeling that can produce a fairly thin sheet.

By the way, in order to make a sheet as thin as possible without creating pinholes, the amount of resin should be 0.2 to 0.4 kg/i,
The amount of glass fiber is preferably in the range of 0.1 to 0.2 kg/m2.

Depending on the application, it can be used as the center core of sandwich panels.
In some cases, it is good to have ventilation.

In this case, glass cloth may be used as shown in Example 4. In this case, if a coarse glass cloth of 1" is used for profiteering, the resin will harden only on the fibers and the crossed fibers will There is a gap in the resin between the
This allows very uniform pinpoles to be formed over the entire surface.

Note that it is also possible to manufacture a glass chopper instead of the crow cloth. In order to form thick pin poles, it is best to make the sheet as thin as possible and to set the glass fiber distribution ratio higher than the amount of resin applied.

[Effects of the Invention] According to the present invention, it is possible to manufacture an FRP core shrine at an extremely low cost, which was considered difficult in the past, and furthermore, it is possible to continuously manufacture an FRP sheet having a rolled core shape in cross section. This has new industrial effects. In addition, according to the present invention, instead of manufacturing the bent core shrine from a flat plate in two steps, it is manufactured by molding it into an S-shape from the beginning and hardening it, so that the mechanical equipment required for manufacturing is occupied. The floor space, including the length of the furnace, can also be significantly reduced compared to that of a flat plate.

As described above, the present invention is extremely significant in that it has enabled continuous S-shaped FRP sheets to be produced from a laboratory scale to industrial production, and it has made it possible to provide an inexpensive FRP core.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the entire process showing an example of carrying out this method, Fig. 2 is a sectional view showing a state in which a round bar for forming is pulled out from a sheet after forming, and Fig. 3 is a formed sheet. Explanatory diagram showing the state in which the carrier film is peeled off from the
The figure is a perspective view showing the appearance of the core material produced by the method of the present invention, and FIGS. 5 and 6 are perspective views showing the appearance of the product obtained by the invention. 1.9: carrier film, 2: resin solution, 3: coating roll, 4: coating layer of resin liquid, 5: short glass fiber, 7: cutting device, 11: nip roll, 12: molding device, 13: molding rear resin sheet, 14: conveyor, 15: peeling jig, 16: reheating device, 17: cutter, 2
2.23: Round bar for molding, 24.25: Guide plate, 26
: Housing, 27: Heat lamp, Figure 2 Figure 4 Figure 3 Figure 6 Figure 5

Claims (1)

[Scope of Claims] 1. A flexible carrier film is continuously fed out, and an uncured resin solution of a thermosetting resin is uniformly applied to the surface of the film, and then the surface of the coating liquid is applied. After scattering or placing glass fiber as a base material on the substrate, another flexible carrier film is layered on top of the glass fiber and the coating liquid is pressed and degassed from above and below to form a thin resin sheet. Furthermore, this sheet was wrapped around a number of heated round bars together with the carrier film, the whole was bent so as to form a continuous S-shape, the sheet was molded and cured in that shape, and then the round bars were separated. Then, the method for producing a core material is performed by peeling off the films disposed on both sides of the sheet. 2. After uniformly applying an unsaturated polyester resin liquid onto a continuously flowing carrier film, glass fibers cut into short lengths were uniformly sprinkled on the surface of the resin liquid, or glass cloth was placed on the surface of the resin liquid. After that, a carrier film is layered on top of this and run, and the resin liquid is pressed and degassed to form a relatively thin resin sheet layer.This sheet layer is then passed through a number of heated round rods. The resin sheet layer and the carrier film are wrapped around the round bar in a continuous S-shape, and the round bar is molded and cured. a second step of separating the resin sheet layer; a third step of peeling off the carrier film disposed on both sides of the resin sheet layer from the sheet layer; and further cutting the molded and cured resin sheet layer to a required length. A method for manufacturing an FRP core material, characterized in that the fourth step of laminating and adhering them is combined. 3 Claims 1 to 2 in which the amount of unsaturated polyester resin as an uncured resin solution is 0.2 to 0.4 kg/m^2
The method described in any of the paragraphs. 4 The amount of glass fiber as the base material is 0.1 to 0.2 kg/
The method according to any one of claims 1 to 3, wherein m^2. 5. The method according to any one of claims 1 to 4, wherein the glass fiber is a plain weave glass cloth weighing 0.1 to 0.2 kg/m^2. 6. The method according to any one of claims 1 to 5, wherein the temperature of the molding round bar is maintained at a substantially constant temperature of 80 to 120°C and used cyclically. 7. The peeling of the film is carried out by keeping the temperature of the molded sheet below 50°C and using a peeling jig.
The method described in any of the paragraphs. 8. After peeling off the film, the molded sheet is reheated to a temperature close to that during molding, and the molded product is continuously corrected so that the continuous S-shaped shapes are in contact with each other. The method described in. 9. Claims 1 to 8, wherein a coarse glass cloth is used as the base material and resin gaps are formed between the crossed fibers, thereby forming uniform pinholes over the entire surface. the method of. 10 By using a glass chop as a base material and making the spraying ratio of glass fiber higher than the amount of resin to be applied between the amount of the glass chop and the amount of resin applied to the surface of the carrier film, the 9. The method according to claim 1, wherein uniform pinholes are formed over the entire area of the resin sheet. 11 A flexible carrier film is continuously fed out, and an uncured resin solution of a thermosetting resin is uniformly applied to the surface of this film, and then glass as a base material is applied to the surface of the coating solution. After scattering or placing the fibers, another flexible carrier film is layered on top of the fibers and run, and the base material and the coating liquid are pressed and degassed from above and below to form a thin resin sheet. The sheet is wrapped around a number of heated round rods together with the carrier film, bent so that the entire sheet forms a continuous S-shape, and then molded and cured in that shape. After the round rods are removed, both sides of the sheet are bent. A resin sheet produced by peeling off the film placed on the film is cut to the required length, and then laminated and bonded to form an F.
RP core material.