JPH0899366A - Manufacture of fiber reinforced resin formed body - Google Patents

Abstract

PURPOSE: To obtain a fiber reinforced resin formed body with a wall thickness and being lightweight, however, having a good mechanical strength, moreover, having a smooth surface and capable of expressing patterns and the like in its surface. CONSTITUTION: While the fiber reinforced strip body F1 comprising a number of coupled reinforcing fiber 10 crossing roughly over the upper and lower layers of woven fabric reinforcing fiber being separated one another is forwarded in one direction, thermoplastic resin sheets 2,3 are laminated integrally, then uncured thermosetting resin is impregnated in the fiber reinforced strip portion. The sheet covered resin impregnated fiber reinforced strip body F2 is introduced in a heat hardening mold 6 having a forming material conduit 17 being in a pressure reduced condition in order to harden resin and while allowing the covering sheets 2, 3 to be in press contact with the inner surface of the mold, it is pulled out for forming a number of vertically extended fiber reinforced resin coupling portions are formed, thereby obtaining a fiber reinforced resin formed body having hollow portions formed in the part except the coupling portions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a fiber reinforced resin molding.

[0002]

2. Description of the Related Art Conventionally, a fiber form of a reinforcing fiber material used for continuously producing a fiber-reinforced resin molded product having a relatively large thickness is a bundle of fibers aligned in one direction,
It is a woven cloth, a non-woven cloth, or the like, and the molded body is made thick by laminating each of them. However,
In this method, since compression is required for laminating, the specific gravity of the obtained molded product becomes considerably large, and it is difficult to manufacture a fiber-reinforced resin molded product that is lightweight and has excellent mechanical strength.

In order to solve the above problems, therefore, a step of forming a resin layer on the surface of a yarn which becomes a reinforcing fiber, a step of weaving the resin layer-formed yarn into a three-dimensional structure, and a three-dimensional A method for producing a fiber-reinforced resin molded body is known, which comprises a step of heating a fiber structure to melt or solidify a resin layer and molding the resin layer into a predetermined shape (see JP-A-63-60738). .

[0004]

However, in the above-mentioned conventional method, the resin-impregnated three-dimensional fiber structure is taken by a take-up machine and passed through a heat-curing mold to be molded into a predetermined cross-sectional shape. However, since the fibers are woven in a three-dimensional structure in a coarse state to some extent, they are easily deformed in the thickness direction when passing through the mold. Therefore, it is difficult for the fibers to come into close contact with the inner surface of the mold, so that the surface of the molded product is not smooth.

When the molded body is not required to have such high strength, a method may be adopted in which the inside of the molded body is hollow to reduce the weight. In the conventional method, the three-dimensional fiber structure is filled with resin. Since it is uniformly impregnated and cured by heating, it is difficult to obtain a hollow molded body.

Further, in the above-mentioned conventional method, if a pattern or the like is to be displayed on the surface of the molded product, it is inevitable to rely on post-processing such as painting, resulting in an increase in the number of steps and an increase in cost.

An object of the present invention is to provide a method for producing a fiber-reinforced resin molded product which is thick and lightweight, has excellent mechanical strength, has a smooth surface, and is capable of showing a pattern on the surface. Especially.

[0008]

According to a first aspect of the present invention, there is provided a method for producing a fiber-reinforced resin molded product, wherein a woven or non-woven reinforcing fiber upper and lower layers separated from each other and a large number of coarsely spread over the upper and lower layers. The step of laminating and integrating a thermoplastic resin or a paper sheet on the upper and lower surfaces of the reinforcing fiber belt made of the connecting reinforcing fibers in one direction, and the uncured thermosetting resin on the reinforcing fiber belt portion. Step of impregnation and sheet-covered resin impregnated reinforcing fiber strips are guided to a heat-hardening mold whose molding material passage is in a depressurized state to cure the resin and the cover sheet is pulled out while being pressed against the inner surface of the mold, and a fiber-reinforced resin A step of forming a large number of fiber-reinforced resin connecting portions extending in the vertical direction between the upper and lower layers and forming a space portion in a portion other than the connecting portions.

The method for producing a fiber-reinforced resin molded product according to the second aspect of the present invention comprises reinforcing fiber upper and lower layers made of woven or non-woven fabric separated from each other and a large number of connecting reinforcing fibers roughly laid over the upper and lower layers. A step of impregnating an uncured thermosetting resin while feeding the reinforcing fiber strip in one direction,
A step of laminating and integrating a thermoplastic resin or a paper sheet on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip, and guiding the sheet-covered resin-impregnated reinforcing fiber strip to a heat-curing mold whose molding material passage is in a reduced pressure state. The resin is hardened and the cover sheet is pulled out while being pressed against the inner surface of the mold to form a number of fiber reinforced resin connecting parts extending vertically between the fiber reinforced resin upper and lower layers and forming a space part in the part other than the connecting parts. And a step of performing.

The method for producing a fiber-reinforced resin molded product according to the third aspect of the present invention comprises reinforcing fiber upper and lower layers made of woven or non-woven fabric separated from each other, and a large number of connecting reinforcing fibers roughly spread over the upper and lower layers. A step in which a thermoplastic resin or a paper sheet is laminated and integrated on the upper and lower surfaces of the reinforcing fiber belt while feeding it in one direction, and a step in which the uncured expandable thermosetting resin is sequentially impregnated in the reinforcing fiber belt portion. Then, the sheet-covered resin-impregnated reinforcing fiber strip is guided to a heat-curing mold to foam and cure the resin, and the cover sheet is pulled out while being pressed against the inner surface of the mold by foaming pressure, and vertically between the fiber-reinforced foamed resin upper and lower layers. Forming a large number of extended fiber-reinforced foamed resin connecting portions and filling the portion other than the fiber-reinforced foamed resin connecting portions with a foamed resin body.

The method for producing a fiber-reinforced resin molded product according to the invention of claim 4 comprises woven or non-woven reinforcing fiber upper and lower layers separated from each other and a large number of connecting reinforcing fibers roughly laid over the upper and lower layers. A step of feeding the reinforcing fiber strip in one direction and impregnating it with an uncured foamable thermosetting resin, and laminating and integrating a thermoplastic resin or a paper sheet on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip. Step and sheet coating resin impregnated reinforcing fiber strips are guided to a heat curing mold for foaming and curing, and the coating sheet is pulled out while being pressed against the inner surface of the mold by foaming pressure and extended vertically between the fiber-reinforced foamed resin upper and lower layers. Forming a large number of fiber-reinforced foamed resin connecting parts and filling a portion other than the fiber-reinforced foamed resin connecting parts with a foamed resin body.

Specific examples of the reinforcing fiber include glass fiber,
Examples thereof include carbon fiber, aramid fiber, vinylon fiber and the like. Roving cloth and the like are suitable as the woven cloth, and chopped strand mat and continuous mat are suitable as the non-woven cloth. These basis weights are 5
It is about 00 to 1500 g / m ² . Although one woven fabric or one non-woven fabric is usually used for each of the upper and lower layers, a plurality of woven fabrics or non-woven fabrics may be stacked and used.

The above-mentioned bridging of connecting fibers means that fibers are interposed between the reinforcing fiber upper and lower layers, and the upper and lower layers are connected by the fibers in the thickness direction. Therefore, the connecting fibers may be locked only to the fibers on the opposing surfaces of the upper layer and the lower layer, or may be in a state in which the upper layer and the lower layer are loosely sewn with the connecting fibers.

As a method for distributing the connecting fibers, for example, a weaving machine capable of weaving two woven fabrics at the same time is adjusted so that during the weaving of the woven fabric, the weaving pattern of the woven fabric can be the same or unrelated to the woven fabric. A method of reciprocating and passing the yarn between two woven fabrics (the obtained product is commercially available as Parabeam 3D from Parabeam Co., Ltd.), and connecting fibers are moved between two woven or nonwoven fabrics at a constant pitch. However, it is not limited thereto.

Specific examples of the thermosetting resin used in the inventions of claims 1 and 2 include unsaturated polyester resins, epoxy resins, vinyl ester resins and phenol resins.

Specific examples of the foamable thermosetting resin used in the inventions of claims 3 and 4 include those obtained by adding a foaming agent to the thermosetting resin to impart foamability. Specific examples of the foaming agent include nitrogen gas, freon gas and ethanol in the physical foaming agent, and inorganic sodium bicarbonate in the chemical foaming agent, azodicarbonamide and dinitroso which are organic pyrolyzable foaming agents. Examples include pentatetramine and the like. Then, a solvent and a monomer that dissolve it in the resin solid content, other fillers used as necessary, additives, and the like are mixed, and both thermosetting resin and expandable thermoplastic resin are resin liquids. used.

Examples of the thermoplastic resin for the sheet include polyvinyl chloride and polyethylene. As a method of expressing a pattern or the like on a sheet, it is general to print or transfer the pattern or the like on the surface of the sheet.

In order to laminate the sheets on the upper and lower surfaces of the reinforcing fibers or the resin-impregnated reinforcing fiber strips, in the case of a thermoplastic resin sheet, the strips and the sheet are superposed and heated from above and below by a press or the like. The thermoplastic resin may be softened and fused to the band-shaped body, or a suitable adhesive may be applied to the surface of the thermoplastic resin or the paper-shaped band-shaped body to be bonded to the band-shaped body, or it may be melted by heating. Alternatively, they may be adhered by coating with an adhesive exhibiting an adhesive force.

According to the first and second aspects of the present invention, in order to reduce the pressure of the molding material passage of the heat-hardening die, the molding material passage upper and lower wall surfaces of the die have a narrow width of 0.
5-10mm slit or diameter 1.0-3.0mm
1 to a plurality of holes are formed facing each other, are connected to the vacuum pump through the gas passage and the gas suction pipe, and the vacuum pump is operated. The shape and number of the openings are set in consideration of the molding material, the drawing speed, and other factors. Further, it is preferable that the corner portion between the opening portion and the molding material passage has a curved surface in order to reduce frictional resistance. The radius of curvature may be 1/5 to 1/2 of the slit width or hole diameter.

The degree of pressure reduction is usually 750 mmHg in vacuum degree.
Around (absolute pressure 10 mmHg) is preferable. In the present invention, the term "fiber-reinforced resin molded product" includes the meaning of "fiber-reinforced foamed resin molded product", but the latter term will be used when the latter is emphasized and described.

[0021]

Since the inventions of claims 1 and 2 have the above-mentioned constitution, the obtained fiber reinforced resin molded body has a large number of fiber reinforced resin connecting portions extending vertically between the fiber reinforced resin upper and lower layers and the connecting portions. Since a space is provided in the other parts, unlike the hollow molded body, not only mechanical strength is imparted by a large number of fiber-reinforced resin connecting portions, but also thickness is imparted to the molded body. Then, the space between the upper and lower layers other than the connecting portion reduces the weight of the molded body.

Further, according to the method of the inventions of claims 1 and 2,
The sheet-covered resin-impregnated reinforcing fiber strip is guided to a heat-curing mold where the molding material passage is in a depressurized state to cure the resin and the cover sheet is pulled out while being pressed against the inner surface of the mold, so the upper and lower surfaces of the molded body are made of glass. It becomes a smooth surface with almost no eyes.

Since the invention of claims 3 and 4 has the above-mentioned constitution, the obtained fiber reinforced resin molding is obtained by arranging the fiber reinforced foamed resin with a large number of fiber reinforced fibers extending vertically between the fiber reinforced foamed resin upper and lower layers. Since the foamed resin connecting part is formed and the part other than the connecting part is filled with the foamed resin body, not only the molded article is given a thickness by the two, but also the presence of the foamed body makes the molded body lightweight. As a result, a large number of fiber-reinforced foamed resin joints provide excellent mechanical strength.

According to the method of the present invention as defined in claims 3 and 4,
Sheet-covered resin-impregnated reinforcing fiber strips are guided to a heat-curing mold to foam and cure the resin, and the covering sheet is pulled out while being pressed against the inner surface of the mold by foaming pressure, so there are almost no glass eyes on the upper and lower surfaces of the molded body. It becomes a smooth surface.

The expansion ratio of the resin in the upper and lower layers of the fiber-reinforced foamed resin and the connection part of the fiber-reinforced foamed resin is considerably lower than the expansion ratio of the foamed resin body that fills the other portions.

[0026]

EXAMPLES Examples of the invention of claim 1 together with comparative examples,
This will be described below. Example 1 First, an example of an apparatus used for carrying out the method for producing a fiber-reinforced resin molded product according to the invention of claim 1 will be described.
In the following description, the term “front” refers to the right direction in FIGS. 1, 4, 5, and 7.

In FIG. 1, a feeding machine (not shown) for the thermoplastic resin sheets (2) and (3) is provided above and below the heating pinch roller (1), and a reinforcing fiber strip (F1) is provided in the middle thereof. ) Feeding machines (not shown) are arranged respectively, and in front of the heating pinch roller (1), uncured thermosetting resin injection nozzle (4) and resin impregnation amount adjustment pinch roller (5) ),
A heat curing mold (6) and a take-up machine (7) are arranged.

As shown in FIG. 2, the reinforcing fiber strip (F1) is roughly woven on the upper and lower layers (8) and (9) and the upper and lower layers (8) and (9) of the woven fabric-made reinforcing fibers separated from each other. It is composed of a large number of bundled connecting reinforcing fibers (10). The nozzles (4) are located in a laterally opposed manner with a space slightly wider than the width of the reinforcing fiber strip (F1), and are provided from the uncured thermosetting resin tank (12) equipped with the pump (11). 2 from one main conduit (13) extending
It is attached to the end of a branched conduit (14). On the upper and lower surfaces of the latter half of the heat curing mold (6), the heater (15)
And three cooling water passages (16) are provided in the upper and lower parts, respectively. In front of the cooling water passage (16), three long and narrow slits (18) each having a width of 2 mm are formed in the upper and lower walls of the molding material passage (17) so as to extend in the passage width direction and have 50 mm intervals in the front-rear direction. There is. The upper and lower three slits (18) are gathered in one gas passage (19) reaching the upper and lower surfaces of the heat curing mold (6), respectively. The end of the gas passage (19) is the main suction pipe extending from the vacuum pump (20).
It is airtightly connected to the end of the branch suction pipe (22) which is divided into two from (21). Also, the heat curing mold (6) has a length of 1
It has a smooth mold surface of m and a width of 9 cm, and the vertical interval is 6 mm.

Next, a method for producing a fiber-reinforced resin molded product using the above apparatus will be described. Reinforcement fiber strip (F1) is fed from the middle feeding machine, thermoplastic resin sheets (2) and (3) are fed from the upper and lower feeding machines, respectively, and the reinforcing fiber belt (F1) is fed in one direction to the upper and lower surfaces thereof. The thermoplastic resin sheets (2) and (3) are laminated and integrated by a pinch roller (9) heated to 60 to 70 ° C.

Next, the uncured thermosetting resin is pumped (1
It is supplied from the tank (12) to the left and right nozzles (4) by 1) and injected into the reinforcing fiber strip (F1) from both sides to impregnate it with an uncured thermosetting resin. The excess resin liquid is squeezed out by passing through the impregnation amount adjustment pinch roller (5) and applying pressure there.

Next, the sheet-covered resin-impregnated reinforcing fiber strip (F2) is evacuated to an absolute pressure of about 10 mmHg in the molding material passage (17) by the operation of the vacuum pump (20), and the mold temperature is 80-. Heat-curing mold set to 120 ° C
Guide to (6) to cure the resin and cover sheet (2)
With (3) pressed against the inner surface of the mold, the take-up speed is 20 cm /
Extracted in minutes, as shown in Fig. 3, fiber reinforced resin upper and lower layers
(21) A plurality of fiber-reinforced resin connecting parts (23) extending vertically are formed between (21) and (22), and a space part (24) is formed in a part other than the connecting parts (23) to form a belt-shaped fiber-reinforced resin molding. Get the body (P1),
This is cut sequentially with a cutter (not shown), and the length is 50c.
A fiber-reinforced resin molded product having m, a width of 9 cm and a thickness of 6 mm was obtained.

As a reinforcing fiber belt, a large number of bundled connecting reinforcing fibers are roughly spread over the upper and lower glass fiber woven fabrics (manufactured by Parabeam, Parabeam 3D86088, basis weight 860 g / m ² , thickness 6 mm). Liquid unsaturated polyester resin 1 as an uncured thermosetting resin
To 100 parts by weight (styrene content of about 40% by weight), 1.2 parts by weight of t-butylperoxybenzoate, 10 parts by weight of calcium carbonate, and 1 part by weight of orthophosphoric acid internal release agent were added. Using. The thermoplastic resin of the sheets (2) and (3) is polyvinyl chloride, and 60 to 7 is provided on one side of the sheets (2) and (3).
Uses one coated with an adhesive that melts at about 0 ° C and exerts adhesive strength, and the coated surface is a reinforced fiber band.
The heating pinch roller (1) is fed so that it comes to the (F1) side.
As a result, the adhesive is melted.

Example 2 A fiber reinforced resin molding was obtained in the same manner as in Example 1 except that a polyvinyl chloride sheet having a wood grain pattern printed thereon was used.

Comparative Example 1 A fiber reinforced resin molding was obtained in the same manner as in Example 1 except that the molding material passage of the heat curing mold was not depressurized.

Comparative Example 2 The same procedure as in Example 1 was carried out except that a glass roving (Asahi Fiber Co., No. 4450) and a continuous mat (Asahi Fiber Co., No. 450) were laminated as the reinforcing fiber strip. A fiber-reinforced resin molded body was obtained.

Next, an embodiment of the invention of claim 2 will be described below together with a comparative example. Example 3 First, an example of an apparatus used for carrying out the method for producing a fiber-reinforced resin molded product according to the invention of claim 2 will be described.

In FIG. 4, uncured thermosetting resin (R1)
A thermoplastic resin sheet (2) (3) delivery machine (not shown) is provided above and below the resin impregnation tank (31) filled with the above, and a reinforcement fiber strip (F1) delivery machine is provided in the middle. (Not shown) is arranged, and in front of the resin impregnation tank (31), the resin impregnation amount adjustment pinch roller (32), the heat curing mold (6) and the take-up machine (7) are arranged in sequence. ing.

A guide roller (33) is arranged inside the resin impregnating tank (31) and in the upper rear part thereof. Heat curing mold
Since (6) and the detailed structure of the decompression device are the same as those in FIG. 1, the same parts as those in FIG. Next, a method for producing a fiber-reinforced resin molded product using the above device will be described. A reinforcing fiber strip (F1) similar to that of Example 1 was fed from the middle feeding machine, and a thermoplastic resin sheet (2) (3) similar to that of Example 1 was fed from the upper and lower feeding machines.
Respectively, and while feeding the reinforcing fiber strip (F1) in one direction, pass through the resin impregnation tank (31) and immerse it in the uncured thermosetting resin (R1), impregnate this, and then impregnate the resin. The excess resin liquid is squeezed out by passing it through the amount adjustment pinch roller (32) and applying pressure there.

Next, the thermoplastic resin sheets (2) and (3) are laminated and integrated on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip by a pinch roller (33) heated to 60 to 70 ° C. Next, the sheet-covered resin-impregnated reinforcing fiber strip (F2) has an absolute pressure of 10 m when the molding material passageway (17) is operated by the vacuum pump (20).
The pressure is reduced to about mHg and the mold temperature is 80-
The sheet is guided to a heat-curing mold (6) set at 120 ° C. to cure the resin, and the covering sheets (2) and (3) are pressed against the inner surface of the mold and pulled out at a take-up speed of 20 cm / min.
As shown in Fig. 5, a large number of fiber-reinforced resin connecting portions (23) extending in the vertical direction are formed between the fiber-reinforced resin upper and lower layers (21) and (22), and a space (24 ) Is formed to obtain a belt-shaped fiber-reinforced resin molding (P1), which is sequentially cut by a cutter (not shown) to obtain a fiber-reinforced resin molding having a length of 50 cm, a width of 9 cm, and a thickness of 6 mm.

Comparative Example 3 Fiber-reinforced resin molding was carried out in the same manner as in Example 3, except that the resin-impregnated reinforcing fiber strip was introduced into the heat-curing mold without laminating the sheets on the upper and lower surfaces of the reinforcing fiber strip. Got the body

An embodiment of the invention of claim 3 will be described below together with a comparative example. Example 4 First, an example of an apparatus used for carrying out the method for producing a fiber-reinforced resin molded product according to the invention of claim 3 will be described.
In FIG. 5, above and below the heating pinch roller (1),
Feeding machine for thermoplastic resin sheets (2) (3) (not shown)
However, in the middle, a feeding machine (not shown) for the reinforcing fiber strip (F1) is arranged, and in front of the heating pinch roller (1), uncured foamable thermosetting A resin injection nozzle (41), a resin impregnation amount adjustment pinch roller (5), a heat curing mold (40) and a take-up machine (7) are arranged.

The nozzles (41) are arranged in a laterally opposed manner with a space slightly wider than the width of the reinforcing fiber strip (F1), and the uncured foamable thermosetting resin provided with the pump (42). Tank (4
The main conduit (44) extending from 3) is attached to the end of a branched conduit (45) which is divided into two.

A heater (15) is provided on the upper and lower surfaces of the latter half of the heat-curing mold (40).
One cooling water passage (16) is provided.

Next, a method for producing a fiber-reinforced foamed resin molded product using the above apparatus will be described. The reinforcing fiber strip (F1) similar to that in Example 1 was fed out from the middle feeding machine, and the thermoplastic resin sheets (2) and (3) similar to those in Example 1 were fed out from the upper and lower feeding machines, respectively. While feeding F1) in one direction, the thermoplastic resin sheets (2) and (3) are heated to 60 to 70 ° C on the upper and lower surfaces of the pinch roller (9).
The layers are integrated by using.

Next, the uncured foamable thermosetting resin is supplied from the tank (43) to the left and right nozzles (41) by the pump (42), and is injected into the reinforcing fiber strip (F1) from both sides. Then, this is impregnated with an uncured expandable thermosetting resin, and then passed through a resin impregnation amount adjustment pinch roller (5), and pressurized here to squeeze out excess resin liquid.

Next, the sheet-covered resin-impregnated reinforcing fiber strip (F2) is introduced into a heat-curing mold (40) set at a mold temperature of 90 to 110 ° C. to foam and cure the resin, and the cover sheet (2 ) (3) is pulled out while being pressed against the inner surface of the mold by foaming pressure, and as shown in FIG.
1) A plurality of fiber-reinforced foamed resin connecting portions (23) extending in the vertical direction are formed between (22), and the portion other than the connecting portions (23) is filled with a foamed resin body (46) to form a belt-shaped fiber-reinforced foamed resin. Molded body
(P2) is obtained, and this is sequentially cut with a cutter (not shown),
A fiber-reinforced foamed resin molded product having a length of 50 cm, a width of 9 cm and a thickness of 6 mm was obtained.

As the uncured expandable thermosetting resin, 100 parts by weight of a liquid phenol resin and 3 parts by weight of ethanol as a foaming agent were used.

Comparative Example 4 The same procedure as in Example 4 was carried out except that a glass roving (Asahi Fiber Co., No. 4450) and a continuous mat (Asahi Fiber Co., No. 450) were laminated as the reinforcing fiber strip. A fiber-reinforced resin molded body was obtained.

Next, an embodiment of the invention of claim 4 will be described below together with a comparative example. Example 5 First, an example of an apparatus used for carrying out the method for producing a fiber-reinforced resin molded product according to the invention of claim 4 will be described.
In FIG. 7, a feeding machine (not shown) for the thermoplastic resin sheets (2) and (3) is provided above and below the resin impregnation tank (51) filled with the uncured foamable thermosetting resin (R2). However, a feeding machine (not shown) for the reinforcing fiber strip (F1) is arranged in the middle, and in front of the resin impregnation tank (51), the resin impregnation amount adjustment pinch roller (52), A heat curing mold (40) and a take-up machine (7) are arranged.

A guide roller (53) is arranged inside the resin impregnation tank (51) and in the upper rear part thereof. Heat curing mold
Since the detailed structure of (40) is the same as that of FIG. 5, the same portions as those of FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted. Next, a method for producing a fiber-reinforced foamed resin molded product using the above apparatus will be described. The reinforcing fiber strip (F1) similar to that in Example 1 was fed out from the middle feeding machine, and the thermoplastic resin sheets (2) and (3) similar to those in Example 1 were fed out from the upper and lower feeding machines, respectively. While feeding F1) in one direction, it passes through the resin impregnation tank (51) and is immersed in the uncured foamable thermosetting resin (R2), and after impregnating this, the resin impregnation amount adjustment pinch roller (52) And pressurize here to squeeze out excess resin liquid.

Next, the thermoplastic resin sheets (2) and (3) are laminated and integrated on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip by a pinch roller (53) heated to 60 to 70 ° C. Next, the sheet-covered resin-impregnated reinforcing fiber strip (F2) is guided to a heat-curing mold (40) set at a mold temperature of 90 to 110 ° C. to foam and cure the resin, and the covering sheet (2) (3 ) Is pulled out while being pressed against the inner surface of the mold by foaming pressure, and as shown in FIG. 7, a large number of fiber-reinforced foamed resin connecting portions (23) extending vertically between the fiber-reinforced foamed resin upper and lower layers (21) (22). Along with the formation of the resin, the parts other than the connecting part (23) are filled with the foamed resin body (46) to obtain a strip-shaped fiber-reinforced foamed resin molded body (P2), which is sequentially cut by a cutter (not shown) to obtain a length. A fiber-reinforced foamed resin molding having a size of 50 cm, a width of 9 cm and a thickness of 6 mm was obtained.
The same uncured foamable thermosetting resin as in Example 5 was used.

Comparative Example 5 Fiber-reinforced resin molding was carried out in the same manner as in Example 5 except that the resin-impregnated reinforcing fiber strip was introduced into the heat-curing mold without laminating the sheet on the upper and lower surfaces of the reinforcing fiber strip. Got the body

For the fiber-reinforced resin moldings obtained in Examples 1 to 5 and Comparative Examples 1 to 5, the surface smoothness, the apparent specific gravity, and the weight fiber content were measured, and bending was performed in the shape of the moldings thus obtained. The rigidity and the appearance were evaluated. The results are shown in Table 1.

[0054]

[Table 1] The surface roughness Rz is 10-point average roughness, and the fiber content is
It was measured according to JIS K7052. The flexural rigidity was measured according to JIS K7055.

As can be seen from Table 1, in Examples 1 to 5, the thermoplastic resin sheets are laminated and integrated on the upper and lower surfaces of the reinforcing fiber strip, and the coated sheet is pulled out and the inner surface of the die is used. Since the surface of the molded body was made to be smooth, the surface of the molded body was smooth, and in particular, a grain pattern could be obtained on the sheet in Example 2, but in Comparative Examples 1 to 4, glass grains were raised on the surface and the appearance was impaired. Further, in Comparative Example 5, the foamable thermosetting resin present in the surface layer also foams, so that air bubbles remain on the surface of the molded body. Further, the molded products of Examples 1 to 5 have improved flexural rigidity as compared with the molded products of Comparative Examples 1, 2 and 5 having a wavy surface. Further, since the molded body of Comparative Example 3 has no space portion and the molded body of Comparative Example 4 does not have only a foamed portion, the flexural rigidity value is high, but the specific gravity is correspondingly large, and the molded articles of Examples 1 to 1 It can be said that the molded body of No. 5 is superior in bending rigidity per unit weight.

[0056]

EFFECTS OF THE INVENTION According to the method for producing a fiber-reinforced resin molded product according to the inventions of claims 1 to 4, the fiber-reinforced resin molded product is thick and lightweight, yet has excellent mechanical strength. It is possible to obtain a fiber-reinforced resin molded product that can represent

[Brief description of drawings]

1 is a schematic longitudinal sectional view of an apparatus used for carrying out the method of the invention of claim 1;

FIG. 2 is a partially enlarged perspective view of a reinforcing fiber strip.

FIG. 3 is a partially enlarged vertical cross-sectional view of a fiber reinforced resin reinforcement obtained by the method of the first and second aspects of the invention.

FIG. 4 is a schematic longitudinal sectional view of an apparatus used for carrying out the method of the invention of claim 2;

FIG. 5 is a schematic longitudinal sectional view of an apparatus used for carrying out the method of the invention of claim 3;

FIG. 6 is a partially enlarged vertical cross-sectional view of a fiber reinforced resin reinforcing body obtained by the method of the invention of claims 3 and 4.

FIG. 7 is a schematic longitudinal sectional view of an apparatus used for carrying out the method of the invention of claim 4;

[Explanation of symbols]

 (2) (3): Sheet (6) (40): Heat curing mold (8): Reinforcing fiber upper layer (9): Reinforcing fiber lower layer (10): Continuous reinforcing fiber (21): Fiber reinforced foam resin upper layer ( 22): Fiber reinforced foamed resin lower layer (23): Fiber reinforced foamed resin connecting part (24): Space part (46): Foamed resin body (F1): Reinforcing fiber strip (F2): Sheet-covered resin impregnated reinforced fiber strip Body (R1): uncured thermosetting resin (R2): uncured foamable thermosetting resin

Claims (4)

[Claims] 1. A woven or non-woven reinforcing fiber upper and lower layers separated from each other, and a reinforcing fiber strip composed of a large number of connecting reinforcing fibers roughly laid over the upper and lower layers while being fed in one direction to the upper and lower surfaces thereof. , A step of laminating and integrating a thermoplastic resin or a paper sheet, a step of impregnating the uncured thermosetting resin in the reinforcing fiber strip portion, and a sheet material resin-impregnated reinforcing fiber strip in a molding material passage in a depressurized state The resin sheet is guided to a heat-curing mold that has been made to cure the resin, and the cover sheet is pulled out while being pressed against the inner surface of the mold to form a large number of fiber-reinforced resin connecting portions extending vertically between the fiber-reinforced resin upper and lower layers and connecting them. And a step of forming a space portion in a portion other than the portion, the method for producing a fiber-reinforced resin molded body. 2. A reinforced or woven or non-woven reinforcing fiber upper and lower layers separated from each other and a plurality of connecting reinforcing fibers roughly laid between the upper and lower layers are fed in one direction and uncured. A step of impregnating the thermosetting resin of
A step of laminating and integrating a thermoplastic resin or a paper sheet on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip, and guiding the sheet-covered resin-impregnated reinforcing fiber strip to a heat-curing mold whose molding material passage is in a reduced pressure state. The resin is hardened and the cover sheet is pulled out while being pressed against the inner surface of the mold to form a number of fiber reinforced resin connecting parts extending vertically between the fiber reinforced resin upper and lower layers and forming a space part in the part other than the connecting parts. The manufacturing method of the fiber-reinforced resin molded body characterized by including the process of performing. 3. A woven or non-woven reinforcing fiber upper and lower layers separated from each other, and a reinforcing fiber strip composed of a large number of connecting reinforcing fibers roughly laid over the upper and lower layers while being fed in one direction to the upper and lower surfaces thereof. , A step of laminating and integrating a thermoplastic resin or a paper sheet, a step of sequentially impregnating the uncured foamable thermosetting resin into the reinforcing fiber strip portion, and a sheet of resin-impregnated reinforcing fiber strip heat-cured While guiding the mold to foam and harden the resin and pull out the cover sheet while pressing it against the inner surface of the mold with foaming pressure, forming a large number of fiber reinforced foam resin connecting parts extending vertically between the fiber reinforced foam resin upper and lower layers, And a step of filling a portion other than the fiber-reinforced foamed resin connecting portion with the foamed resin body, the method for producing a fiber-reinforced resin molded body. 4. A reinforced or woven or non-woven reinforcing fiber upper and lower layers separated from each other and a plurality of connecting reinforcing fibers roughly spread over the upper and lower layers are fed in one direction and uncured. The step of impregnating the foamable thermosetting resin, the step of laminating and integrating the thermoplastic resin or the paper sheet on the upper and lower surfaces of the resin-impregnated reinforcing fiber strip, and the heat curing of the sheet-covered resin-impregnated reinforcing fiber strip. It is guided to the mold to be foamed and cured, and the cover sheet is pulled out while being pressed against the inner surface of the mold by the foaming pressure to form a number of fiber-reinforced foamed resin connecting parts extending vertically between the upper and lower layers of the fiber-reinforced foamed resin. And a step of filling a portion other than the reinforced foamed resin connecting portion with the foamed resin body, the method for producing a fiber-reinforced resin molded body.