JP2012096482A - Fiber reinforced molded article and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber reinforced molded article, which is lightweight, has high rigidity, and has excellent surface appearance after coating when the surface is coated, and from which the coating is unlikely to be peeled.SOLUTION: The fiber reinforced molded article 10 comprises a core material 11 made of a synthetic resin, which consists of a resin foam or the like having interconnected cells, a fiber reinforcement material 21 in which a fiber fabric such as a carbon fiber fabric is impregnated with a thermosetting resin to be cured, and a surface material 25 in which a porous sheet having interconnected cells at a rate of 8 to 80 cells/25 mm is impregnated with a thermosetting resin to be cured. The fiber reinforcement material and the surface material are stacked on at least one surface of the core material in order, and the core material 11, the fiber reinforcement material 21, and the surface material 25 are integrated by curing of the thermosetting resin to form the fiber reinforced molded article 10.

Description

  The present invention relates to a fiber reinforced molded body in which a fiber reinforcing material and a surface material are laminated and integrated on at least one surface of a core material, and a manufacturing method thereof.

  In recent years, a fiber-reinforced molded body has been proposed as a member that requires high rigidity, such as a casing of a notebook computer. As a fiber reinforced molded object, there exists a carbon fiber reinforced body obtained by laminating | stacking a carbon fiber prepreg and carrying out reaction hardening, for example. Examples of fiber reinforced molded bodies using carbon fibers include the following.

Patent Document 1 discloses a fiber reinforced molded product in which a plurality of fiber reinforced layers in which continuous fibers of carbon fibers are arranged in a sheet shape in one direction are laminated in a specific arrangement direction.
Patent Document 2 discloses a sandwich structure made of a core material having a gap and a fiber reinforcing material made of continuous carbon fibers and a matrix resin disposed on both sides of the core material.
Patent Document 3 discloses a composite molding in which a continuous fiber reinforced fabric containing at least carbon fibers is placed on both sides of a soft member layer, a sheet is set in an injection mold, and a resin part is injection molded on the side of the sheet. The product is disclosed.

  Further, in Patent Document 4, as a method for producing an elastic sandwich-type composite material, fabric sheets made of glass fibers impregnated with an epoxy resin are arranged above and below in a mold, and a urethane resin is interposed between the fabric sheets. A method of foaming a foam is disclosed (Example 1 of Patent Document 4).

  However, a fiber reinforced molded body having a fiber woven fabric such as a carbon fiber woven fabric or a glass fiber woven fabric on the surface has a space between the portion 215 where the fibers overlap on the surface of the molded body and the portion of the gap 216 of the weave as shown in FIG. As a result, the surface unevenness degree is large due to the effect of the step and the like, and even if the appearance is applied, the effect of the step cannot be reduced and it is difficult to obtain surface smoothness. Reference numeral 221 denotes a transverse fiber, and 222 denotes a longitudinal fiber. Moreover, when an external appearance coating is applied, air may remain in the stepped portion and a pinhole may be generated on the surface of the coating film. In particular, in an application in which appearance painting is generally performed from the viewpoint of improving aesthetic appearance, the appearance state when the appearance painting is performed is important. Furthermore, in general, the compatibility (adhesiveness) between an inorganic material such as carbon fiber and a urethane paint or UV paint is not good, and the coating film may be peeled off.

JP 2004-209717 A WO2006 / 028107 JP 2007-038519 A Japanese Patent Laid-Open No. 01-163020

  The present invention has been made in view of the above points, and has a fiber-reinforced molded body that has a small degree of unevenness (surface roughness) on the surface before coating, has a good appearance when coated, and does not cause the coating film to peel off. It aims at providing the manufacturing method.

  The invention of claim 1 is a fiber reinforced molded body in which a fiber reinforcing material is laminated on at least one surface of a core material, and a surface material is laminated on the fiber reinforcing material, and the core material is made of synthetic resin. The fiber reinforcing material is made of a fiber woven fabric impregnated with a thermosetting resin and cured, and the surface material is thermosetting to a porous sheet having open cells of 8 to 80 cells / 25 mm. It is characterized by comprising a resin impregnated and cured and having a surface roughness of 30 μm or less.

According to a second aspect of the present invention, in the first aspect, the porous sheet is made of a resin foam.
The invention of claim 3 is characterized in that, in claim 2, the resin foam comprises a urethane resin foam.
According to a fourth aspect of the present invention, in any one of the first to third aspects, the thermosetting resin is made of a phenol resin or an epoxy resin.

A fifth aspect of the present invention provides the core material according to any one of the first to fourth aspects, wherein the core material is formed by impregnating and curing a resin foam having open cells with a thermosetting resin. The fiber reinforcing material and the surface material are the thermosetting resin impregnated in the resin foam having open cells, the thermosetting resin impregnated in the fiber fabric, and the thermosetting impregnated in the porous sheet. It is characterized by being integrated by curing the resin.
The invention of claim 6 is characterized in that, in any one of claims 1 to 5, a coating film is provided on the surface of the surface material, and the surface roughness of the coating film is 25 μm or less.

  According to the seventh aspect of the present invention, at least one surface of a synthetic resin core material is laminated with a fiber reinforcing material obtained by impregnating and curing a fiber fabric with a thermosetting resin, and the foam sheet having open cells is thermosetting. In the method for producing a fiber reinforced molded article in which a surface material impregnated with resin and cured is laminated on the fiber reinforcement, the number of cells is 8 to 80 cells / 25 mm and the thickness is as the foam sheet having the open cells. Using one having a diameter of 0.4 to 3.0 mm, impregnating or adhering a thermosetting resin to one or both of the core material member and the fiber fabric, and the fiber fabric on at least one surface of the core material By sequentially laminating the foam sheet having the open cells, heating and compressing the core member, the fiber fabric, and the foam sheet having the open cells, and curing the thermosetting resin, Whether the core member The core material formed, the fiber reinforcing material impregnated and cured with a thermosetting resin in the fiber fabric, and the surface material impregnated with a thermosetting resin into the foam sheet having the open cells and cured. It is characterized by integrating.

  The present invention related to a fiber reinforced molded article has a good rigidity because a fiber reinforcing material obtained by impregnating a fiber woven fabric with a thermosetting resin and being cured is laminated on at least one surface of the core material, and further fiber reinforced. The surface material laminated on the material is impregnated with a thermosetting resin in a porous sheet having open cells of 8 to 80 cells / 25 mm and cured, and the surface material has a surface roughness of 30 μm or less. Therefore, on the surface where the surface material is laminated, a step generated in a gap portion of the weave of the fiber fabric constituting the fiber reinforcing material is filled with a thermosetting resin impregnated in the porous sheet and cured, thereby reinforcing the fiber. The surface of the molded body becomes smooth. Furthermore, when coating is applied to the surface of the surface material, the surface roughness of the coating can be reduced to 25 μm or less to suppress the effect of the step of the fiber fabric, and air remains in the step. This eliminates the possibility of pinholes on the surface of the coating film and provides a good coating appearance. In addition, the surface material improves the adhesion to the paint and prevents the coating film from peeling off. In addition, the surface roughness (degree of unevenness in the examples) in the present invention refers to a ten-point average roughness (RzJIS82) measured using a surface roughness meter with respect to the test surface.

  Moreover, the present invention relating to a method for producing a fiber-reinforced molded body can easily obtain a fiber-reinforced molded body that can realize high rigidity and good appearance.

It is sectional drawing of one Embodiment of the fiber reinforced molded object in this invention. It is sectional drawing of one Embodiment of the fiber reinforced molded object which provided the coating film on the surface of the surface material. It is a figure which shows the process of 1st Embodiment of the manufacturing method in this invention. It is a figure which shows the process of 2nd Embodiment of the manufacturing method in this invention. It is a figure which shows the process of 3rd Embodiment of the manufacturing method in this invention. It is the top view and sectional drawing of a textile fabric.

Hereinafter, the fiber reinforced molded product and the manufacturing method thereof of the present invention will be described with reference to the drawings.
A fiber reinforced molded body 10 according to an embodiment of the present invention shown in FIG. 1 includes a core material 11, a fiber reinforcing material 21 laminated and integrated on both surfaces of the core material 11, and at least one side of the core material 11. The surface material 25 is laminated and integrated on the surface of the fiber reinforcing material 21, and the surface of the surface material 25 is coated and used for a housing of a portable device such as a notebook computer. In the illustrated example, the fiber reinforcing material 21 and the surface material 25 are laminated on the core material 11 only on the side 111 on which the coating is performed in the fiber reinforced molded body 10, and the side 112 on which the coating is not performed is as follows. Only the fiber reinforcing material 21 is laminated, and the surface material 25 is not laminated. Depending on the use or the like of the fiber-reinforced molded body 10, the side 112 on which the coating is not performed may be configured such that neither the fiber reinforcing material 21 nor the surface material 25 is laminated. In addition, for the purpose of coating on both sides of the fiber reinforced molded body 10, the surface material 25 is preferably laminated and integrated on the surface of the fiber reinforcing material 21 on both sides of the core material 11.

  The fiber-reinforced molded body 10 has a plate shape of a predetermined size, a thickness of 0.3 to 2.0 mm, and a flexural modulus (JIS K7074-1988 A method) of 30 GPa to 60 GPa, more preferably 35 GPa. It is preferably 55 GPa or less and a specific gravity of 1.2 to 1.5, more preferably 1.28 to 1.35. If the thickness is less than 0.3 mm, it is difficult to obtain rigidity, whereas if the thickness is greater than 2.0 mm, the entire portable device becomes thick. When the fiber-reinforced molded body 10 is used as a casing of a portable device, the side walls of the casing are appropriately erected at a predetermined surface position by so-called outsert molding such as injection molding.

  The core material 11 is made of a synthetic resin sheet or plate, and in particular, a resin foam having open cells impregnated with a thermosetting resin and cured is preferable. The resin foam having open cells is not particularly limited, and can be selected from, for example, a urethane resin foam or a melamine resin foam. When the fiber reinforced molded body 10 is required to have flame retardancy, the thermosetting resin foam is preferably flame retardant, and the melamine resin foam has a good flame retardancy as a single resin. The thermosetting resin foam is suitable.

  Further, it is preferable that the core material 11 is obtained by impregnating a resin foam having open cells with a thermosetting resin, and curing the thermosetting resin in a state where the resin foam is compressed. When the thermosetting resin is cured in a state where the resin foam is compressed, the fiber-reinforced molded body 10 can be thinned and the rigidity can be improved. The degree of compression is preferably such that the thickness of the fiber-reinforced molded body is 0.3 to 2.0 mm during the production of the fiber-reinforced molded body described later.

Although the original thickness before compression of the resin foam for the core material 11 varies depending on the compression rate, for example, when trying to obtain a fiber-reinforced molded body having a thickness of 2 mm or less, the original thickness is preferably 1 to 25 mm. When the original thickness is within this range, an appropriate amount of thermosetting resin can be impregnated, and the yield after heat compression is good. If the original thickness is less than 1 mm, the impregnated thermosetting resin cannot be held in the resin foam, and the resin ratio varies, so that the flexural modulus (rigidity) is lowered. When the original thickness is greater than 25 mm, when trying to obtain a fiber reinforced molded product having a thickness of 2 mm or less, compression is difficult and a fiber reinforced molded product having a uniform thickness cannot be obtained. The resin foam for the core material 11 preferably has a density before compression of 5 to 80 kg / m ³ from the viewpoints of easy compression, impregnation, light weight, and rigidity.

  The thermosetting resin impregnated into the resin foam for the core material 11 is not particularly limited, but in order to increase the rigidity of the fiber reinforced molded body 10, the thermosetting resin itself needs to have a certain degree of rigidity. Yes, it can be selected from the group consisting of epoxy resins, phenol resins, and mixtures of epoxy resins and phenol resins. When the fiber reinforced molded body 10 is required to have flame retardancy, the thermosetting resin is preferably flame retardant. Since the phenol resin has good flame retardancy, it is suitable as a thermosetting resin impregnated in the resin foam.

The fiber reinforcing material 21 is made by impregnating a fiber fabric with a thermosetting resin and curing it. Examples of the fiber woven fabric include those made of glass fiber, carbon fiber, etc. In particular, the carbon fiber woven fabric is preferable as the fiber woven fabric because it is excellent in light weight and high rigidity. Further, the fiber woven fabric preferably has a weaving method in which the fibers are not only in one direction, for example, a plain weave composed of warp and weft, a twill weave, a satin weave, and a triaxial weave composed of three-direction yarn. Is preferred. When a carbon fiber fabric is used as the fiber fabric, the carbon fiber fabric preferably has a fiber weight of 90 to 400 g / m ² from the viewpoint of impregnation with a thermosetting resin and rigidity.

  The thermosetting resin impregnated in the fiber fabric is not particularly limited, but in order to increase the rigidity of the fiber reinforced molded body 10, the thermosetting resin itself needs to have a certain degree of rigidity. It can be selected from the group consisting of resins, mixtures of epoxy resins and phenolic resins. When the fiber reinforced molded body 10 is required to have flame retardancy, the thermosetting resin impregnated in the fiber fabric is preferably flame retardant. Since the phenol resin has good flame retardancy, it is suitable as a thermosetting resin impregnated in the fiber fabric.

  In addition, a melamine resin is used for the resin foam for the core material 11, and the thermosetting resin impregnated in the resin foam (melamine resin foam) and the thermosetting resin impregnated in the fiber fabric are phenol resin. In this case, it is possible to obtain a fiber reinforced molded article having sufficient flame retardancy for a casing of a portable device such as a notebook personal computer without using a flame retardant.

In addition, the amount of the thermosetting resin in the entire fiber reinforced molded body 10 is a resin ratio obtained by [thermosetting resin (weight) in fiber reinforced molded body / fiber reinforced molded body (weight) × 100] ( The weight ratio is preferably 50 to 80%, more preferably 55 to 70%. By setting it as the said resin ratio, even if it thins the said fiber reinforced molded object 10, lightness and rigidity can be made more favorable.
In addition, the weight of the thermosetting resin in the fiber reinforced molded body in the formula of the resin ratio is the weight after removing the solvent when the thermosetting resin is dissolved in the solvent.

  The surface material 25 is made of a porous sheet impregnated with a thermosetting resin and cured. In the compression heating process at the time of manufacturing the fiber reinforced molded body 10 described later, the surface material 25 is impregnated into the porous sheet and oozes out from the surface of the porous sheet and hardens. A smooth resin layer is formed, and the surface roughness is 30 μm or less, more preferably 24 μm or less. When the surface roughness is larger (rougher) than 30 μm, when the surface of the surface material 25 is coated, the unevenness is conspicuous and it becomes difficult to obtain a good coated surface.

  The porous sheet is a porous sheet having continuous cells (having a large number of pores) in order to improve the impregnation of the thermosetting resin and form a uniform resin layer. The material of the porous sheet is not particularly limited, but is porous with open cells (having a large number of pores) and does not melt by heat in the compression heating process and does not fill the pores. Those having the heat resistance of 1 are preferred. Further, the form of the porous sheet is not particularly limited, and can be appropriately selected from woven fabric, nonwoven fabric, paper, foam and the like. Furthermore, if a resin foam having open cells is used for the porous sheet of the surface material, the skeleton shape of the resin is stably maintained as compared with the porous body made of fibers, so that air permeability and The fluidity of the matrix resin becomes good, the surface of the porous sheet is easily oozed out, and the surface is easily smoothed. Among resin foams having open cells, a porous sheet made of urethane resin foam is easy to handle, has excellent lightness, and has an effect of steps such as gaps in the texture of the fiber fabric of the fiber reinforcing material 21 by compression. It can be relaxed and is preferable.

  When the porous sheet is a urethane resin foam, a urethane resin foam from which the cell membrane has been removed by a known film removal treatment such as a dissolution treatment or an explosion treatment is particularly preferable. Since the urethane resin foam from which the cell membrane has been removed has an open cell structure, the thermosetting resin is impregnated into the porous sheet in the compression heating step during the production of the fiber reinforced molded body 10, and the porous sheet The core material 11, the fiber reinforcing material 21, and the surface material 25 are more surely integrated by curing the thermosetting resin, and the surface of the porous sheet oozes out. The cured thermosetting resin is cured to form a resin layer with a smoother surface. In addition, since the cell membrane remains in the urethane resin foam from which the cell membrane has not been removed, when used for a porous sheet, impregnation and exudation of the thermosetting resin is not good, resulting in smooth surface. And coating adhesion (hardness of peeling of the coating film) are lowered.

  The porous sheet preferably has 8 to 80 cells / 25 mm (JIS K6400-1). When the number of cells is less than 8 pieces / 25 mm, the gap (pores) becomes too large when processed into a thin sheet, and the amount of thermosetting resin necessary to fill the irregularities of the fiber fabric is retained. Tend to be difficult. On the other hand, when the number of cells is more than 80/25 mm, the voids are reduced and the impregnation property of the thermosetting resin is lowered, and the thermosetting resin is sufficiently oozed out from the surface of the porous sheet. Becomes difficult.

  Although the thickness of the porous sheet to be used varies depending on the material, it is 0.4 mm to 3.0 mm, more preferably 0.6 mm to 3.0 mm in an uncompressed state (before the production of the fiber reinforced molded body). When the thickness in the non-compressed state is smaller than 0.4 mm, it becomes difficult to form a uniform resin layer on the surface of the surface material 25 in the compression heating process at the time of manufacturing the fiber reinforced molded body 10, and the fiber reinforced molded body The smoothness of the surface of 10 will fall. On the other hand, when the thickness of the porous sheet in the non-compressed state (before the production of the fiber reinforced molded body) is larger than 3.0 mm, the bending elastic modulus of the fiber reinforced molded body 10 is lowered and the fiber reinforced molded body 10 is reduced. In the manufacturing process, the seepage unevenness of the thermosetting resin from the porous sheet is likely to occur, and the surface smoothness of the surface material 25 decreases.

  The core material 11, the fiber reinforcing material 21, and the surface material 25 are integrated by impregnating or applying one or both of the core material and the fiber fabric with a thermosetting resin, and then at least one surface of the core material ( In the above example, the fiber woven fabric and the porous sheet can be laminated in order on both surfaces), and the thermosetting resin can be cured in a compressed state. When a thermosetting resin is applied or impregnated to both the core material and the fiber fabric, a thermosetting resin impregnated or applied to the core material and a thermosetting resin impregnated or applied to the fiber fabric; These may be the same type or different types, but the same type is preferable for improving the adhesion between the core material 11 and the fiber reinforcing material 21.

  The surface of the surface material 25 in the fiber reinforced molded body 10 is coated by a predetermined method according to the use, and a coating film is formed. Examples of the paint include urethane, acrylic, polyester, and vinyl acetate, and examples of the coating method include spray coating, coater coating, and dipping coating. Although the coating amount is determined as appropriate, a film thickness of 5 to 40 μm is given as an example. FIG. 2 shows a fiber reinforced molded body 100 in which a coating film 27 is provided on the surface of the surface material 25 by painting. The surface roughness comprising the degree of unevenness of the coating film 27 is 25 μm or less, more preferably less than 20 μm.

Next, the manufacturing method of the fiber reinforced molded body of the present invention will be described taking the manufacturing of the fiber reinforced molded body 10 as an example. The method for manufacturing the fiber-reinforced molded body 10 includes an impregnation or adhesion process, a lamination process, and a compression heating process.
First, the first embodiment will be described. In the manufacturing method of the first embodiment, in the impregnation or adhesion step (3-1) shown in FIG. 3, the fiber woven fabric 21A is impregnated or adhered with the thermosetting resin 21B to form the impregnated or adhered carbon fiber woven fabric 21C. To do. The fiber fabric 21A and the thermosetting resin 21B are as described in the fiber reinforced molded body 10. The thermosetting resin 21B used at the time of impregnation or adhesion is made of an uncured liquid. In order to facilitate the impregnation or adhesion, the thermosetting resin 21B is preferably dissolved in a solvent. After the impregnation or adhesion, the impregnated or adhered fiber fabric 21C is subjected to a curing reaction of the thermosetting resin. By drying at a temperature that does not occur, the solvent is removed from the impregnated or adhered fiber fabric 21C. The impregnation or adhesion means can be performed by an appropriate method such as a method of immersing the fiber fabric 21A in a tank containing the liquid thermosetting resin 21B, a method of applying by spraying, a method of applying by a roll coater. At that time, it is preferable to impregnate or attach the thermosetting resin 21B to the fiber fabric 21A so that the formula resin ratio is 50 to 80%, particularly 55 to 70%. In the first embodiment, only the fiber fabric 21A is impregnated with the thermosetting resin 21B in the impregnation or adhesion step.

  In the laminating step (3-2) shown in FIG. 3, the impregnated or adhered fiber fabric 21C obtained in the impregnation or adhering step of (3-1) is disposed on both surfaces of the core member 11A. Furthermore, a porous sheet 25A for a surface material is disposed on the surface of the impregnated or adhered fiber fabric 21C on one side of the core member 11A to form a laminate 10A. The core material member 11 </ b> A and the porous sheet 25 </ b> A are as described in the fiber reinforced molded body 10. The laminating operation is performed on the upper surface of the press-molding lower mold 31 used in the compression heating step (3-3) to be performed next, the impregnated or adhered fiber fabric 21C, the core member 11A, the impregnation or Alternatively, the attached fiber fabric 21C and the porous sheet 25A may be stacked in this order. Further, the impregnated or adhered fiber fabric 21C, the core member 11A, and the porous sheet 25A preferably have the same plane size, but if they are different, they are trimmed after the compression heating step described later. That's fine.

  In the compression heating step (3-3) shown in FIG. 3, the laminate 10A is compressed and heated by the press mold lower mold 31 and the upper mold 33. The compression is preferably performed so that the thickness of the laminated body 10A is 0.3 to 2.0 mm. During the compression heating step, a spacer is installed at an appropriate position between the press molding lower mold 31 and the upper mold 33, and a predetermined interval (predetermined of the laminate) is provided between the press molding lower mold 31 and the upper mold 33. Compression thickness). The heating method of the laminated body is not particularly limited, but heating means such as a heater is provided in the lower mold 31 for press molding and the upper mold 33, and heating is performed via the lower mold 31 for press molding and the upper mold 33. It's easy. The heating temperature is set to be equal to or higher than the curing reaction temperature of the impregnated thermosetting resin.

  When the laminate 10A is compressed during the compression heating step, a thermosetting resin is extruded from the impregnated or attached fiber fabric 21C of the laminate 10A, and the core is in contact with the impregnated or attached fiber fabric 21C. It adheres to or impregnates the material member 11A and impregnates the porous sheet 25A. The thermosetting resin impregnated in the porous sheet 25A oozes out on the surface of the porous sheet 25A to form a uniform resin layer. At that time, excess thermosetting resin exceeding the space volume of the thermosetting resin foam, fiber fabric, and porous sheet after compression is pushed out of the mold, and minute voids present in the thermosetting resin Except for minute voids that are not intentionally formed, the laminate is substantially free of voids. The thermosetting resin impregnated or adhered to the laminated body 10A starts a curing reaction by heating, and is cured in a state where the laminated body 10A is compressed. When the core member 11A is made of a resin foam having open cells, the core member 11A is impregnated with the thermosetting resin of the impregnated or attached fiber fabric 21C and compressed. The thermosetting resin is cured. When the porous sheet 25A is made of a urethane resin foam, the thermosetting resin is cured while the porous sheet 25A is also compressed. The core material 11 is formed from the core material member 11A, the fiber reinforcing material 21 is formed from the impregnated or adhered fiber fabric 21C, and the surface material 25 is formed from the porous sheet 25A. The core material 11, the fiber reinforcing material 21, and the surface material 25 are integrated to form the fiber reinforced molded body 10. Thereafter, the heat compression is released to obtain the fiber reinforced molded body 10. In the fiber reinforced molded body 10 thus obtained, the surface of the surface material 25 is a smooth resin layer by curing of the thermosetting resin that has oozed out on the surface of the porous sheet 25A.

  In the second embodiment of the manufacturing method, the thermosetting resin 11B is impregnated or adhered to the core member 11A in the impregnation or adhesion step (4-1) shown in FIG. A foam 11C is formed. When the core member 11A is made of a resin foam having open cells, the core member 11A is impregnated with the thermosetting resin 11B, while the core member 11A is impregnated. In the case of a difficult member, for example, a non-porous member, the thermosetting resin 11B is adhered to the surface of the core member 11A. The core member 11A and the thermosetting resin 11B are as described in the fiber-reinforced molded body 10. The thermosetting resin 11B used at the time of impregnation or adhesion is made of an uncured liquid. Further, in order to facilitate the impregnation or adhesion, the thermosetting resin 11B is preferably dissolved in a solvent, and after impregnation or adhesion, the impregnated or adhered core member 11C is subjected to a curing reaction of the thermosetting resin. The solvent is removed from the impregnated or adhered core member 11C by drying at a temperature that does not occur. The impregnation or adhesion means is carried out by an appropriate method such as a method of immersing the core member 11A in a tank containing the liquid thermosetting resin 11B, a method of applying by spraying, a method of applying by roll coater.

It is preferable that the thermosetting resin 11B is impregnated or adhered to the core member 11A so that the resin ratio is 50 to 80%, particularly 55 to 70%.
In the second embodiment, only the core member 11A is impregnated with the thermosetting resin 11B in the impregnation or adhesion step. The thermosetting resin 11B impregnated or attached to the core member 11A impregnates the fiber fabric 21A and the porous sheet 25A in a compression heating step as will be described later.

  In the laminating step (4-2) shown in FIG. 4, the fiber fabric 21A is disposed on both surfaces of the impregnated or adhered core member 11C, and further on one side of the impregnated or adhered core member 11C. A porous sheet 25A is arranged on the surface of the fiber fabric 21A on the surface to obtain a laminate 10B. The fiber fabric 21A and the porous sheet 25A are as described in the fiber reinforced molded body 10. The laminating operation is performed on the upper surface of the press molding lower mold 31 used in the compression heating step (4-3) to be performed next, the fiber fabric 21A, the impregnated or adhered core member 11C, and the fiber fabric. 21A and the porous sheet 25A may be stacked in this order. Further, the impregnated or adhered core member 11C, the fiber fabric 21A, and the porous sheet 25A preferably have the same planar size, but if they are different, the compression heating step described below is finally performed. Just trim it.

  In the compression heating step (4-3) shown in FIG. 4, the laminate 10 </ b> B is compressed and heated by the press mold lower mold 31 and the upper mold 33. The compression is preferably performed so that the thickness of the laminate 10B is 0.3 to 2.0 mm. During the compression heating step, a spacer is installed at an appropriate position between the press molding lower mold 31 and the upper mold 33, and a predetermined interval (predetermined of the laminate) is provided between the press molding lower mold 31 and the upper mold 33. Compression thickness). Further, the heating method of the laminate is not particularly limited, and heating means such as a heater is provided in the press molding lower mold 31 and the upper mold 33, and the heating is performed via the press molding lower mold 31 and the upper mold 33. Is simple. The heating temperature is set to be equal to or higher than the curing reaction temperature of the impregnated thermosetting resin.

  When the laminate 10B is compressed during the compression heating step, when the core member is made of a resin foam having open cells, a thermosetting resin is introduced from the impregnated or adhered core member 11C. Extruded and impregnated into the fibrous fabric 21A in contact with the impregnated or adhered core member 11C, and further impregnated into the porous sheet 25A. On the other hand, when the core member is made of a member that is difficult to impregnate, for example, a non-porous member, the thermosetting resin is compressed by the fiber fabric 21A from the surface of the attached core member 11C. And further impregnating the porous sheet 25A. The thermosetting resin impregnated in the porous sheet 25A oozes out on the surface of the porous sheet 25A to form a uniform resin layer. At that time, excessive thermosetting resin that exceeds the space volume of the core member, fiber fabric, and porous sheet after compression is pushed out of the mold to form minute voids and intentions present in the thermosetting resin. Except for the minute voids that are not formed, the laminate is substantially free of voids. The thermosetting resin impregnated or adhered to the entire laminated body 10B starts a curing reaction by heating and is cured in a compressed state of the laminated body 10B. When the core member 11A is made of a resin foam having open cells, the thermosetting resin is cured in a compressed state. When the porous sheet 25A is made of a urethane resin foam, the thermosetting resin is cured while the porous sheet 25A is also compressed. Thereby, the core material 11 is formed from the impregnated or adhered core material member 11C, the fiber reinforcing material 21 is formed from the fiber fabric 21A, and the surface material 25 is formed from the porous sheet 25A. Then, the core material 11, the fiber reinforcing material 21, and the surface material 25 are integrated to form the fiber reinforced molded body 10. Thereafter, the heat compression is released to obtain the fiber reinforced molded body 10. In the fiber reinforced molded body 10 thus obtained, the surface of the surface material 25 is a smooth resin layer by curing of the thermosetting resin that has oozed out on the surface of the porous sheet 25A.

In the third embodiment of the manufacturing method, the impregnation or adhesion step is composed of two types of steps: an impregnation or adhesion step A and an impregnation or adhesion step B.
As shown in (5-1) in FIG. 5, in the impregnation or adhesion step A, the core member 11A is impregnated or adhered with the thermosetting resin 11B to obtain the impregnated or adhered core member 11C. On the other hand, in the impregnation or adhesion step B, the fiber woven fabric 21A is impregnated or adhered with the thermosetting resin 21B to form the impregnated or adhered fiber woven fabric 21C. The core member 11A, the thermosetting resin 11B, the fiber fabric 21A, and the thermosetting resin 21B are as described in the fiber reinforced molded body 10. The thermosetting resins 11B and 21B used at the time of impregnation or adhesion are made of an uncured liquid. In order to facilitate impregnation or adhesion, the thermosetting resins 11B and 21B are preferably dissolved in a solvent. After impregnation or adhesion, the impregnated or adhered core member 11C and the impregnated or adhered fiber fabric 21C are used. Is dried at a temperature that does not cause a curing reaction of the thermosetting resin, and the solvent is removed from the impregnated or adhered core member 11C and the impregnated or adhered fiber fabric 21C. The impregnation or adhesion means is performed by an appropriate method such as a method of immersing the core member or fiber fabric in a tank containing a liquid thermosetting resin, a method of applying by spraying, a method of applying by a roll coater, or the like.

  In the impregnation or adhesion of the thermosetting resin 11B to the core member 11A and the impregnation or adhesion of the thermosetting resin 21B to the fiber fabric 21A, the resin ratio is 50 to 80%, particularly 55. It is preferable to be set to ˜70%.

  In the laminating step (5-2) shown in FIG. 5, the impregnated or adhered fiber fabric 21C is disposed on both surfaces of the impregnated or adhered core material member 11C, and the impregnated or adhered core material member is further disposed. A porous sheet 25A is arranged on the surface of the impregnated or adhered fiber fabric 21C on the surface on one side of 11C to obtain a laminate 10C. The porous sheet 25A is as described in the fiber-reinforced molded body 10. The laminating operation is performed on the upper surface of the press-molding lower die 31 used in the compression heating step (5-3) to be performed next, and the impregnated or adhered fiber fabric 21C and the impregnated or adhered core member 11C. The impregnated or adhered fiber fabric 21C and the porous sheet 25A may be stacked in this order. The impregnated or adhered core material member 11C, the impregnated or adhered fiber fabric 21C, and the porous sheet 25A preferably have the same planar size, but if they are different, the compression heating step described later is performed. After that, it may be finally trimmed.

  In the compression heating step (5-3) shown in FIG. 5, the laminate 10C is compressed and heated by the press molding lower die 31 and the upper die 33. The compression is preferably performed so that the thickness of the laminated body 10C becomes 0.3 to 2.0 mm. During the compression heating step, a spacer is installed at an appropriate position between the press molding lower mold 31 and the upper mold 33, and a predetermined interval (predetermined of the laminate) is provided between the press molding lower mold 31 and the upper mold 33. Compression thickness). The heating method is not particularly limited, and it is easy to perform heating via the press molding lower mold 31 and the upper mold 33 by providing heating means such as a heater in the press molding lower mold 31 and the upper mold 33. is there. The heating temperature is set to be equal to or higher than the curing reaction temperature of the impregnated thermosetting resin.

  The compression in the compression heating step ensures that the thermosetting resin of the impregnated or attached fiber fabric 21C and the thermosetting resin of the impregnated or attached core member 11C are in contact with each other, and the impregnated or attached fiber The porous sheet 25A is impregnated with the thermosetting resin of the fabric 21C. The thermosetting resin impregnated in the porous sheet 25A oozes out on the surface of the porous sheet 25A to form a uniform resin layer. At that time, excessive thermosetting resin that exceeds the space volume of the core member, fiber fabric, and porous sheet after compression is pushed out of the mold to form minute voids and intentions present in the thermosetting resin. Except for the minute voids that are not formed, the laminate is substantially free of voids. And by the heating in the said compression heating process, the thermosetting resin of the said laminated body 10C starts hardening reaction, and it hardens | cures in the compression state of the said laminated body 10C. When the core member 11A is made of a resin foam having open cells, the thermosetting resin is cured in a compressed state. When the porous sheet 25A is made of a urethane resin foam, the thermosetting resin is cured while the porous sheet 25A is also compressed. As a result, the core material 11 is formed from the impregnated or adhered core material member 11C, the fiber reinforcing material 21 is formed from the impregnated or adhered fiber fabric 21C, and the surface material is formed from the porous sheet 25A. 25, the core material 11, the fiber reinforcing material 21, and the surface material 25 are integrated to form the fiber reinforced molded body 10. Thereafter, the heat compression is released to obtain the fiber reinforced molded body 10. In the fiber reinforced molded body 10 thus obtained, the surface of the surface material 25 is a smooth resin layer by curing of the thermosetting resin that has oozed out on the surface of the porous sheet 25A.

  As shown in each of the above-described embodiments, in the impregnation or adhesion step, one or both of the core member and the fiber fabric are impregnated or adhered, and the porous sheet is thermally cured. The porous sheet is impregnated with the thermosetting resin for the first time in the subsequent heat-compression step without impregnating or adhering the curable resin. Therefore, the porous sheet can be laminated without slack in the lamination process, and wrinkles can be prevented from occurring. If the porous sheet is impregnated with the thermosetting resin in the impregnation or adhesion process before lamination, the impregnated porous sheet is loosened and wrinkles during the lamination process, and the surface of the surface material in the fiber reinforced molded article is There is a possibility that the surface is not smooth.

  In addition, as shown in FIG. 2, when a coating film 27 is provided on the surface of the surface material 25, a coating process is performed after the compression heating process in each of the above-described embodiments, and a coating film is formed on the surface of the surface material. Form. In the coating process, the surface of the surface material is coated by spray coating, coater coating, dipping coating or the like, and then dried to form a coating film on the surface of the surface material. The paint is not particularly limited, and as described above, examples thereof include urethane-based, acrylic-based, polyester-based, vinyl acetate-based, and the like, and have a predetermined film thickness, for example, a film thickness of about 5 to 40 μm. Is painted.

Example 1
As a thermosetting resin, phenol resin (Asahi Organic Materials Co., Ltd., product name: PAPS-4 and Asahi Organic Materials Co., Ltd., product name: hexamethylenetetramine mixed at 100: 12) in methanol with a concentration of 30 wt% It dissolved so that it might become. A plain-woven carbon fiber fabric (manufactured by Toho Tenax Co., Ltd., product name: W-3101, fiber weight 200 g / m ² ) is immersed in this phenol resin solution as a fiber fabric. It was dried and further dried at 60 ° C. for 1 hour to form two impregnated fiber fabrics. The carbon fiber fabric used was cut into a plane size of 200 × 300 mm (weight 12 g / sheet). The impregnated fiber fabric after drying was 28 g per sheet.

Further, as a thermosetting resin foam having open cells of the core member, a melamine resin foam cut out to a thickness of 10 mm and a planar size of 200 × 300 mm (weight 5.4 g) (manufactured by BASF, product name: Bazotect V3012, 9 kg / m ³ ) is immersed in a phenolic resin solution in the same manner as the fiber fabric, taken out, dried naturally at room temperature of 25 ° C. for 2 hours, and further dried at 60 ° C. for 1 hour to be impregnated. A core member was formed. The weight of the impregnated core member after drying was 27 g. Moreover, the resin ratio contained in the whole fiber fabric and the core member was 65%.

  Next, an impregnated fiber fabric, an impregnated core material member, an impregnated fiber fabric, and a porous sheet are formed on a lower mold (flat plate shape) made of SUS having a release agent applied to the surface in advance. By placing them one after another, the impregnated fiber fabric is arranged on both sides of the impregnated core member, and the porous sheet is arranged on the surface of the impregnated fiber fabric on one side of the impregnated core member. The laminated body was set on the lower mold for press molding. The porous sheet is a non-compressed thickness of a urethane resin foam (product name: MF-50, bulk specific gravity 0.03, number of cells 50/25 mm, manufactured by Inoac Corporation) from which the cell membrane has been removed by dissolution treatment. What was cut into 0.4 mm was used. In addition, the porosity of the used urethane resin foam is 97.1%. The formula for calculating the porosity is as follows. Porosity (%) = (Urethane resin true specific gravity−bulk specific gravity (≈foam apparent density)) / urethane resin true specific gravity × 100

  In a state where the laminate is set on the lower mold for press molding, the laminate is pressed with the upper mold for press molding (flat plate shape) by applying a surface pressure of 5 MPa at 180 ° C. for 3 minutes, and compressed and heated. Then, the phenol resin was reaction-cured in the compressed state. At that time, the laminate was heated by a casting heater attached to the upper and lower press dies. Further, a 0.9 mm thick SUS spacer was interposed between the lower mold for press molding and the upper mold to adjust the distance between the lower mold and the upper mold, that is, the compression thickness of the laminate. Then, after lowering the press mold lower mold and upper mold at room temperature, the lower mold and upper mold are opened, fiber reinforcing material is laminated on both sides of the core material, and a porous sheet is formed on one side fiber reinforcing material As a result, a fiber-reinforced molded body in which the finished surface material was laminated and integrated was obtained. This fiber reinforced molded body was trimmed to 170 × 260 mm to obtain a fiber reinforced molded body of Example 1.

Example 2
A fiber-reinforced molded article of Example 2 was prepared in the same manner as in Example 1 except that the thickness of the porous sheet in Example 1 (thickness in an uncompressed state) was 0.6 mm.

Example 3
A fiber-reinforced molded article of Example 3 was prepared in the same manner as in Example 1 except that the thickness of the porous sheet in Example 1 (thickness in an uncompressed state) was 1.0 mm.
Example 4
A fiber-reinforced molded body of Example 4 was prepared in the same manner as in Example 1 except that the thickness of the porous sheet in Example 1 (thickness in an uncompressed state) was 2.0 mm.
Example 5
A fiber-reinforced molded body of Example 5 was prepared in the same manner as in Example 1 except that the thickness of the porous sheet in Example 1 (thickness in an uncompressed state) was 3.0 mm.

Example 6
Instead of the porous sheet in Example 1, a urethane resin foam from which the cell membrane was removed by dissolution treatment (product name: MF-80, bulk specific gravity 0.05, number of cells 80/25 mm, manufactured by Inoac Corporation) A fiber-reinforced molded body of Example 6 was prepared in the same manner as in Example 1 except that the porosity was 95.2% and the non-compressed thickness was 1.0 mm.
-Example 7
In place of the porous sheet in Example 1, a urethane resin foam from which the cell membrane was removed by dissolution treatment (manufactured by Inoac Corporation, product name: MF-10, bulk specific gravity 0.028, number of cells 10/25 mm) A fiber reinforced molded article of Example 7 was prepared in the same manner as in Example 1 except that the porosity was 97.3% and the non-compressed thickness was 1.0 mm.
Example 8
Instead of the porous sheet in Example 1, the urethane resin foam from which the cell membrane was removed by dissolution treatment (manufactured by Inoac Corporation, product name: MF-8, bulk specific gravity 0.027, number of cells 8/25 mm) A fiber reinforced molded article of Example 8 was prepared in the same manner as in Example 1 except that the porosity was 97.4% and the non-compressed thickness was 1.0 mm.
Example 9
In place of the porous sheet in Example 1, a urethane resin foam with a cell membrane that has not been subjected to cell membrane removal treatment (product name: SP-50, bulk specific gravity 0.031, number of cells, manufactured by Inoac Corporation) 50/25 mm), a porosity of 97.0%, and a non-compressed thickness of 1.0 mm were used, and a fiber-reinforced molded article of Example 9 was prepared in the same manner as in Example 1.

Comparative example 1
The fiber-reinforced molded body of Comparative Example 1 was prepared without the porous sheet on the surface in Example 1.
Comparative example 2
A fiber-reinforced molded article of Comparative Example 2 was prepared in the same manner as in Example 1 except that the thickness of the porous sheet on the surface in Example 1 (thickness in an uncompressed state) was 4.0 mm.
Comparative example 3
In place of the porous sheet in Example 1, a urethane resin foam from which the cell membrane was removed by dissolution treatment (product name: MF-100, bulk specific gravity 0.075, number of cells 100/25 mm, manufactured by Inoac Corporation) A fiber reinforced molded article of Comparative Example 3 was prepared in the same manner as in Example 1 except that the porosity was 92.8% and the non-compressed thickness was 1.0 mm.

  About each of the said Example and a comparative example, the total thickness and the bending elastic modulus (JIS K7074-1988 A method, fiber direction) before coating, and the unevenness | corrugation degree (surface roughness) of the surface material were measured. The degree of unevenness (surface roughness) was measured with respect to the surface of the surface material by using a surface roughness meter (manufactured by Tokyo Seimitsu, product name: Surfcom 113A), with a 10-point average roughness (RzJIS82) at a reference length of 20 mm. . RzJIS82 is the ten-point average roughness of the old standard JIS B0601: 1982. In the cross-sectional curve of the standard length, the average of the peak height from the highest peak to the fifth highest and the fifth from the deepest valley bottom to the fifth deepest. The average sum of valley depths. The measurement results are shown in Table 1.

  For each of the above Examples and Comparative Examples, the surface of the surface material (the surface of the fiber fabric in Comparative Example 1) is coated with a two-component curable urethane-based paint so as to have a film thickness of 20 μm by spray coating. Was applied to form a coating film, and the coating appearance, the degree of unevenness of the coating surface (surface roughness), and coating adhesion were examined. The appearance of the coating is the appearance of the coating film. When the coating film surface after drying is visually observed, ◎ indicates that the unevenness is not known at all, ○ indicates that the unevenness is slightly recognized, and X indicates that the unevenness is clearly understood. did. The degree of unevenness of the coating surface is the surface roughness of the coating film. Rz: 10 points are measured with respect to the coating film surface after drying using a surface roughness meter (manufactured by Tokyo Seimitsu, product name: Surfcom), and the average It was represented by the surface roughness (μm) of the value. The coating adhesion is the adhesion of the coating film. On the surface of the coating film after drying, 100 mm of grid-like cuts (cross cuts) are formed at intervals of 1 mm using a cutter, and the 100 mm portion where the cuts are formed. The cellophane tape having a width of 25 mm and a length of 75 mm was adhered to the film, and then the cellophane tape was peeled off, and the coating adhesion was expressed by the number of wrinkles (the number of adhesion) in which the coating film was not removed. The measurement results are shown in Table 1.

  In Examples 1 to 9 in which a porous sheet (surface material) was provided on the surface, the degree of unevenness before painting and the degree of unevenness after painting were small compared to Comparative Example 1 in which no porous sheet was provided on the surface. In addition, the coating appearance was good, the coating adhesion was good, and the coating film was difficult to peel off. In particular, when Example 1 and Comparative Example 1 that differ only in the presence or absence of a porous sheet are compared, Comparative Example 1 without a porous sheet is more uneven than before Example 1 and after coating than Example 1 having a porous sheet. Was larger than double, and the coating appearance and coating adhesion were significantly inferior to those of Example 1.

  Further, comparing Example 3 in which the cell membrane of the porous sheet was removed and Example 9 in which the cell membrane of the porous sheet was not removed, Example 3 in which the cell membrane was removed The degree of unevenness before and after coating was less than half that of Example 9 in which no is removed, and the coating appearance and adhesion were also better than Example 9.

  Further, Comparative Example 2, which is the same as Example 1, except that the thickness of the porous sheet (thickness in an uncompressed state) was changed from the thickness of 0.4 mm of Example 1 to 4.0 mm, was compared with Example 1. In addition, the bending elastic modulus was about half, the unevenness before and after coating was extremely large, and the coating appearance and adhesion were inferior to those of Example 1.

  Comparative Example 3 in which the number of cells in the porous sheet was 100/25 mm was the same as in Example 3 (number of cells 50/25 mm), Example 6 (number of cells 80/25 mm), except for the number of cells. Compared to Example 7 (number of cells 10/25 mm) and Example 8 (number of cells 8/25 mm), the unevenness before and after coating is about 2 to 4 times greater than the unevenness. It was also inferior to Examples 3, 6, 7 and 8 in coating appearance and coating adhesion.

  As described above, the product according to the present invention is thin, has high rigidity, has a good appearance when coated, and does not peel off the coating film. Is suitable. In the above embodiment, the surface material (porous sheet) is laminated only on the surface of the fiber reinforcing material on one surface of the core material, but the surface material on the surface of the fiber reinforcing material on both surfaces of the core material. (Porous sheet) may be laminated. Further, depending on the use of the fiber reinforced molded body, the fiber reinforcing material and the surface material may be provided only on one surface of the core material.

DESCRIPTION OF SYMBOLS 10 Fiber reinforced molded object 10A, 10B, 10C Laminated body 11 Core material 11A Core material member 11B Thermosetting resin 11C Impregnated or adhered core material 21 Fiber reinforcement 21A Textile fabric 21B Thermosetting resin 21C Impregnation or adhesion Finished fiber fabric 25 Surface material 25A Porous sheet 27 Paint film

Claims (7)

A fiber reinforced molded body in which a fiber reinforcing material is laminated on at least one surface of a core material, and a surface material is laminated on and integrated with the fiber reinforcing material,
The core material is made of synthetic resin,
The fiber reinforcing material consists of a fiber woven fabric impregnated with a thermosetting resin and cured,
The surface material is made of a porous sheet having open cells of 8 to 80 cells / 25 mm and impregnated with a thermosetting resin, and has a surface roughness of 30 μm or less. Reinforced molded body.   The fiber-reinforced molded body according to claim 1, wherein the porous sheet is made of a resin foam.   The fiber-reinforced molded body according to claim 2, wherein the resin foam is a urethane resin foam.   The fiber-reinforced molded body according to any one of claims 1 to 3, wherein the thermosetting resin is made of a phenol resin or an epoxy resin. The core material is composed of a resin foam having open cells impregnated with a thermosetting resin and cured,
The core material, the fiber reinforcing material, and the surface material are impregnated in the thermosetting resin impregnated in the resin foam having the open cells, the thermosetting resin impregnated in the fiber fabric, and the porous sheet. The fiber-reinforced molded body according to any one of claims 1 to 4, wherein the fiber-reinforced molded body is integrated by curing of the cured thermosetting resin.   The fiber-reinforced molded article according to any one of claims 1 to 5, wherein a coating film is provided on the surface of the surface material, and the surface roughness of the coating film is 25 µm or less. At least one surface of the synthetic resin core material is laminated with a fiber reinforcing material which is cured by impregnating a fiber fabric with a thermosetting resin, and the foam sheet having open cells is impregnated with the thermosetting resin and cured. In the method for producing a fiber-reinforced molded body in which a surface material is laminated on the fiber reinforcing material,
As the foam sheet having open cells, the number of cells is 8 to 80/25 mm, and the thickness is 0.4 to 3.0 mm.
Impregnating or adhering a thermosetting resin to one or both of the core member and the fiber fabric,
The fiber fabric and the foam sheet having the open cells are sequentially laminated on at least one surface of the core member,
The core member and the fiber formed from the core member by heating and compressing the foam member having the core member, the fiber fabric, and the open cells to cure the thermosetting resin. The fiber reinforcing material impregnated and cured with a thermosetting resin in a woven fabric and the surface material impregnated with the thermosetting resin and cured with the foam sheet having the open cells are integrated. A method for producing a fiber-reinforced molded article.

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