JP2009019202A - Molding material, preform and fiber-reinforced resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding material exhibiting excellent handleability, resin impregnability, shaping properties and mechanical properties, a preform and FRP. <P>SOLUTION: The multilayered molding material 1 is prepared by laminating and integrating two or more layers of sheets composed of a large number of reinforcing fiber threads 2 parallelly arranged, and satisfies the following requirements (i) to (iv): (i) a fabric 3, composed of a first thermoplastic resin constituting a matrix of a composite material between the sheets, is arranged; (ii) the laminates are integrated by a stitch yarn 4 composed of a second thermoplastic resin and/or by the fabric 3 composed of the first thermoplastic resin; (iii) the multilayered molding material comprises a sheet comprising a spun yarn constituted of a discontinuous fiber, having a fiber length La of 10-100 mm, of the reinforcing fiber threads constituting the laminates; and (iv) at least 50% of the reinforcing fiber threads constituting the laminates are composed of spun yarn comprising the discontinuous fiber, having a fiber length La of 10-100 mm, of the reinforcing fiber threads constituting the laminates. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molding material having excellent handling properties, resin impregnation properties, and formability, and in producing a fiber reinforced resin (hereinafter referred to as FRP) having excellent mechanical properties and quality. The present invention relates to a suitably used molding material, preform, and FRP comprising the same.

  Conventionally, FRP using carbon fiber or glass fiber as reinforced fiber is superior in specific strength and specific elastic modulus. Therefore, FRP is widely used for aircraft and general industries, such as sports equipment and leisure goods that have a large weight reduction effect. It is used.

  As a method of molding such FRP, a prepreg in which a reinforcing fiber base material is impregnated with a matrix resin in advance is used, this is set in a mold, covered with a bag film, heated and pressurized in an autoclave, and the thermosetting resin is cured. In general, there are widely used autoclave molding methods and vacuum injection molding methods in which a reinforced fiber base material in a dry state is set in a mold, and a liquid thermosetting resin is injected under a reduced pressure (vacuum state) in the mold Are known. However, in the autoclave molding method and the vacuum injection molding method, it is necessary to laminate the base materials, and it is necessary to cover with a bag film and reduce the pressure to a vacuum. In particular, in the vacuum injection molding, it is necessary to inject a thermosetting resin. Further, in these methods, the molding time (cycle time) per process including the above-described steps becomes too long, and it is difficult to adapt to, for example, automobile members having a large number of production.

  To solve this problem, as a means for omitting the lamination process when molding FRP, a multiaxial stitch base material in which reinforcing fiber layers in which reinforcing fiber yarns are oriented in multiple directions is laminated and integrated by stitch yarns is provided. Proposed. However, this technique has a drawback in that it is very difficult to form a single contour shape or a double contour shape because the reinforcing fiber layer is constrained by stitch yarns. In other words, when trying to place this multi-axis stitch base material in the mold, it cannot be shaped into the desired shape by stretching at the curved surface, or the material retains its exact shape as it tries to recover to its original shape. There was a problem that wrinkles occurred even if it could not be done or if it could be shaped.

  As means for improving this problem, it has been proposed to form a stitch yarn with a low melting point polymer (for example, Patent Document 1). However, in this method, since the stitch yarn is composed of a low melting point polymer, it is possible to improve the apparent formability by heating and melting the stitch yarn at the time of shaping, but the stitch yarn is completely When melted, there is a problem that the reinforcing fiber yarns are not restrained, the reinforcing fiber layers are separated, and the shape cannot be maintained and cannot be handled.

  In addition, it has been proposed to form a free end in the surface by making a cut in the prepreg to improve the shapeability (for example, Patent Document 2). However, this method has a problem that wrinkles easily occur unless the resin is impregnated with a resin such as a prepreg because the deformation behavior at the time of shaping differs between the cut and the periphery of the cut.

Furthermore, it has been proposed to improve the formability using a woven fabric made of spun yarn (for example, Patent Document 3). Although this fabric is a fabric with a low basis weight of 100 g / m ² or less using a spun yarn of fineness, the shapeability is excellent, but when the fabric weight is increased, the shapeability is reduced. There's a problem.

  Thus, a material excellent in formability has not been obtained not only in a multiaxial stitch base material but also in a reinforced fiber fabric, and the multiaxial base material obtained by such a conventional technique is in a double contour shape. If the followability is inferior and the follower is forced to follow the curved surface, the reinforcing fibers are scattered, the fiber meanders and the fiber density becomes dense, and not only the high mechanical properties can be exhibited when molded into FRP, but also the surface smoothness There was a problem that it was not possible to obtain an excellent molded product.

  On the other hand, as a means for omitting the resin injection / curing step, a molding material (for example, Patent Document 4) in which fibers made of a thermoplastic resin as a matrix are integrated in advance with reinforcing fiber yarns to form the multiaxial stitch base material. Etc.), and a molding material (for example, Patent Document 5) in which a film made of a thermoplastic resin that becomes a matrix after being melt-impregnated between layers of the multiaxial stitch base is proposed.

  In the method described in Patent Document 4, the resin impregnation property is inferior because the resin is made of thermoplastic resin fibers serving as a matrix in the reinforcing fiber layer of the multiaxial stitch base material. There is a problem that high pressure is required for impregnation. Further, when the reinforcing fiber is impregnated with the thermoplastic resin serving as a matrix, the air present at the location to be impregnated can be efficiently released to the outside of the system, that is, a path of air to the outside of the system can be formed. Importantly, because the fiber made of thermoplastic resin is pre-integrated with the reinforcing fiber, the path to the outside of the system is narrow and easily blocked during pressurization and heating. As a result, in the FRP There is a problem that it tends to remain as a void. Furthermore, since it is necessary to integrate the synthetic resin fiber with the reinforcing fiber in advance, there is a problem that the cost increases due to an increase in the number of steps.

  Further, in the method described in Patent Document 5, since each of the reinforcing fiber layers is thick and has a large basis weight, it is difficult to completely impregnate in the thickness direction after melting the thermoplastic resin film as a matrix. There was a problem.

  In addition, for the problem in the case of using the thermoplastic resin film, a molding material in a prepreg or semi-preg state in which a reinforcing fiber sheet and a nonwoven fabric of a thermoplastic resin are laminated and heated and pressurized has been proposed ( For example, Patent Document 6). However, if the reinforcing fiber is impregnated into the prepreg or semi-preg state over the entire surface of the molding material in the plane direction, there is a problem that the handling property and the shapeability of the molding material are significantly lowered.

That is, in the conventional techniques including Patent Documents 1 to 6, a molding material that has excellent handling properties, resin impregnation properties, and shapeability, and can obtain FRP excellent in mechanical properties and quality with high productivity. Preforms and FRPs composed of them have not been found and such techniques are craved.
JP 2002-227066 A JP-A 63-267523 JP-A-10-280246 Japanese Patent Application Laid-Open No. 2001-073241 JP 2004-346175 A JP 2003-165851 A

  Accordingly, the object of the present invention is to solve the above-mentioned problems of the prior art, and to obtain an FRP having excellent handling characteristics, resin impregnation properties and formability, and excellent mechanical properties and quality with high productivity. It is in providing a molding material, a preform, and FRP using them.

In order to achieve the above object, the present invention adopts the following configuration. That is,
(1) A multilayer molding material in which a plurality of layers of a sheet in which a large number of reinforcing fiber yarns are arranged in parallel is laminated to form a laminate, and the laminate is integrated. The molding material characterized by satisfying the requirements of (c) to (c).
(A) A textile body comprising as a component a first thermoplastic resin constituting a matrix of a composite material is disposed at least between the sheets,
(B) The laminated body is integrated by a stitch yarn having the second thermoplastic resin as a component and / or a textile body having the first thermoplastic resin as a component,
(C) including a sheet which is a spun yarn composed of discontinuous fibers having a finite length of 10 to 100 mm, and the fiber length La of the reinforcing fiber yarn constituting the laminated body,
(D) Spinning in which at least 50% or more of the reinforcing fiber yarns constituting the laminate are composed of discontinuous fibers having a finite length in which the fiber length La of the reinforcing fiber yarns constituting the laminate is 10 to 100 mm. It is a thread.
(2) Each of the sheets constituting the laminate is laminated in a multiaxial orientation so that the reinforcing fiber yarns intersect to constitute a laminate, and the number of axes to be oriented is n-axis, fiber length Molding according to (1) above, where n and N satisfy the relationship of the following formula, where N is the ratio in the molding material of spun yarn composed of discontinuous fibers of finite length with La of 10 to 100 mm material.
(100-100 / n) ≦ N
(3) The molding material according to (1) or (2), wherein the fineness of the spun yarn is 300 to 5,000 tex, and the yarn width W / yarn thickness T is 2 to 20.
(4) The molding material according to any one of (1) to (3), wherein the number of twists of the spun yarn is in the range of 200 to 5 turns / m.
(5) The molding material according to any one of (1) to (3), wherein the spun yarn is substantially untwisted and is covered with an auxiliary fiber yarn and then converged.
(6) The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy the relationship (Tm1-150) ≦ Tm2 ≦ (Tm1-20). The molding material according to any one of 5).
(7) The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy the relationship (Tm2-150) ≦ Tm1 ≦ (Tm2-20). (5) The molding material in any one of.
(8) The melting points Tm1 of the first thermoplastic resin and the melting points Tm2 of the second thermoplastic resin satisfy the relationship of (Tm2-20) <Tm1 <(Tm2 + 20) (1) to (5) ) The molding material according to any one of
(9) Any of (1) to (8), wherein the basis weight of the reinforcing fiber in the sheet is in the range of 50 to 350 g / m ² and the basis weight of the fabric body is in the range of 15 to 250 g / m ^2. Molding material according to crab.
(10) A preform characterized in that one or more of the molding materials according to any one of (1) to (9) are laminated and formed into a single contour shape or a double contour shape.
(11) The length Lc and the fiber length La in the cross section in the reinforcing fiber yarn direction of each sheet constituting the molding material are Lc> La at the portion formed into a single contour shape or a double contour shape. The preform according to (10) above.
(12) A fiber-reinforced resin formed using the molding material or preform according to any one of (1) to (11).

According to the molding material of the present invention, a laminated body is constituted by arranging a textile body comprising a thermoplastic resin as a matrix between sheets made of reinforcing fiber yarns, and the laminated body is stitched yarn and / or Since the first thermoplastic resin is used as a component, the body is integrated, so there is no need to laminate the base material or inject a matrix resin in the preform or FRP molding operation, thus simplifying the molding operation. It can be done quickly and reliably.
In addition, since the fabric body arranged between the layers of the laminate is melted, shear deformation is easily performed between the layers of the laminate, and the spun yarn is applied as the reinforcing fiber yarn, so that each sheet of the laminate is It becomes easy to progress and deform in the plane, and excellent formability can be expressed in the molding of a preform or FRP.

The molding material of the present invention is a multilayer molding material in which a plurality of layers of sheets in which a large number of reinforcing fiber yarns are aligned in parallel are laminated to form a laminate, and the laminate is integrated. The following requirements (a) to (d) are satisfied.
(A) A textile body comprising as a component a first thermoplastic resin constituting a matrix of a composite material is disposed at least between the sheets,
(B) The laminated body is integrated by a stitch yarn having the second thermoplastic resin as a component or a fabric body having the first thermoplastic resin as a component;
(C) including a sheet that is a spun yarn composed of discontinuous fibers having a finite length of 10 to 300 mm, and the fiber length La of the reinforcing fiber yarn constituting the laminated body;
(D) Spinning in which at least 50% or more of the reinforcing fiber yarns constituting the laminate are composed of finite length discontinuous fibers having a fiber length La of 10 to 300 mm of the reinforcing fiber yarns constituting the laminate. It is a thread.

  The sheet constituting the molding material of the present invention includes a group of reinforcing fiber yarns formed by aligning a large number of reinforcing fiber yarns in parallel. Such a sheet is not limited to one in which each of the reinforcing fiber yarn groups is bonded and bonded to each other and can be handled as a single sheet, and only a plurality of reinforcing fiber yarns are arranged in parallel. It may be an apparent sheet, or each of the reinforcing fiber yarn groups arranged in parallel or a part thereof may have a gap.

  Here, aligning in parallel means arranging adjacent reinforcing fiber yarns side by side so as not to substantially intersect or cross each other. More preferably, adjacent reinforcing fiber yarns are continuously arranged at a constant interval of 20 to 200% of the reinforcing fiber yarn width, or are arranged so as to overlap by a certain width within a range not exceeding the reinforcing fiber yarn width. That is. It should be noted that substantially not intersecting or crossing means that even if the reinforcing fiber yarns meander and overlap in the width direction, the width of the narrower one of the adjacent reinforcing fiber yarns is reduced. If it does not overlap, it is not included. Further, the term “constant” here means that the width and interval are within a range of ± 50% from the average value. More preferably, when two adjacent reinforcing fiber yarns are approximated to a straight line within a length range of 100 mm, the angle formed by the approximated straight line is arranged to be 5 ° or less, more preferably It is arranged so as to be 2 °. Note that approximating the yarn to a straight line means that a straight line is formed by connecting a starting point and an ending point of 100 mm.

  As a means for forming a sheet that satisfies such an aspect, for example, the reinforcing fiber yarns may be drawn directly from the bobbin around which the reinforcing fiber yarns are wound and arranged in parallel, or simultaneously from a plurality of bobbins. It may be arranged by pulling out and arranging, or a plurality of reinforcing fiber yarns that have been pre-aligned and processed into a tape shape or a sheet shape may be separately arranged. It may be formed by the same means, and each layer may be formed by each means.

  The laminate constituting the molding material of the present invention is formed by laminating a plurality of layers of the sheet, that is, at least two layers, and the number of layers and the lamination angle are not particularly limited. As a structure of such a laminated body, for example, [0 °] n, [0 ° / 90 °], [+ 45 ° / −45 °], [0 ° / ± 60 °], [−45 ° / 0 ° / + 45]. However, when emphasizing the formability, the biaxially oriented laminate in which the orientations of the reinforcing fiber yarns are orthogonal to each other (for example, [0 ° / 90 °], [+ 45 ° / −45 °]) is preferable, and in such a configuration, when the laminated body exhibits excellent shear deformation and it is desired to reduce the anisotropy of the obtained FRP, the reinforcing fiber yarns are oriented in multiple directions (for example, , [0 ° / + 45 ° / 90 ° / −45 ° /...]), It is possible to give the FRP pseudo-isotropic properties. Stacking in multiple layers can contribute to labor saving in the stacking process.

  Here, although the laminated body of this invention is classified into a unidirectional laminated body and a crossing laminated body, it defines as follows, respectively. The unidirectional laminate is a laminate in which the sheets constituting the laminate are laminated so that the reinforcing fiber directions are the same (for example, [0 °] n, [90 °] n, etc.) The angle formed by the reinforcing fiber direction of each sheet is within ± 5 °. The cross laminate is a laminate in which the sheets constituting the laminate are laminated so that the reinforcing fiber directions intersect (for example, [0 ° / 90 °], [+ 45 ° / −45 °]). , Etc.). In the present invention, that the reinforcing fiber directions intersect each other means that the angle formed by the reinforcing fiber directions of adjacent sheets is ± 5 ° or more, and preferably within a range of 30 ° to 60 °. Here, when the number of orientation directions of the reinforcing fiber layers included in the laminate is n, it is expressed as n-axis orientation. That is, the cross laminate is a laminate having biaxial orientation or more. Furthermore, isotropic lamination such as [−45 / 0 / + 45/90] and [0 / ± 60] is preferable, and more preferable is [−45 / 0 / + 45/90] s and [0 / ± 60] s. Symmetrical lamination. By setting it as this aspect, FRP can be made into a uniform physical property and generation | occurrence | production of the curvature by a thermal stress can be suppressed. In the symmetric lamination, the fiber directions are the same in the two layers at the center in the lamination thickness direction that are turned back, but the two layers in this case are exceptions to the above definition.

  With regard to (a) above, the resin body having the first thermoplastic resin constituting the matrix of the composite material at least as a component between the sheets is disposed, so that the resin impregnating property of the molding material and the first Shapeability can be expressed. Here, the “thermoplastic resin constituting the matrix of the composite material” refers to a thermoplastic resin that becomes a matrix after being molded into a composite material. When molding the molding material, in order to impregnate the reinforcing fiber yarn with the melt of the thermoplastic resin as the matrix, it is important to efficiently release the air present in the molding material out of the system. Therefore, it is important to form a path to the outside of the system. If such a path cannot be formed, air (void) remains in the obtained FRP, which causes the quality and mechanical properties of the FRP to deteriorate. In the above aspect (a), the gap between the single yarns of the reinforcing fiber yarns in the sheet and / or the sheet extending over the entire surface in the plane direction of the molding material is removed by disposing at least the textile body between the sheets. By adopting the route to, it is possible to avoid closing the route to the outside of the air system during molding. In other words, the present invention satisfies the above-mentioned aspect (a), so that it is possible to easily impregnate the thermoplastic resin melt as a matrix even at a low pressure, and to form FRP without voids.

  Moreover, said (a) brings the 1st shaping property to a molding material. The first formability is that, when the FRP is formed by heating the molding material, a space is formed between the layers by melting the fabric body arranged between the layers, and adjacent sheets are sheared between the layers. This means that it is easy to deform. Specifically, when the FRP is molded by heating the molding material, the fabric body arranged between the layers melts, so that the restraint due to stitches described later is relaxed, or even the stitch yarn is melted. The deformation resistance between the respective layers is reduced, and it can be easily deformed by applying a slight external force. That is, the first formability is a shear deformation between layers of the molding material and indicates the shapeability in the thickness direction of the molding material. By having the first formability, particularly in a single contour shape such as a cylinder or a U shape, the inner and outer peripheral length difference generated in the thickness direction of the molding material is absorbed by the shear deformation between layers, and the reinforcing fiber yarn It is possible to form a good-quality FRP along the curved surface portion by suppressing the occurrence of tension and wrinkles. This works more effectively as the thickness of the molding material increases. The single contour shape as used in the present invention refers to the kind of curved surface shape, and when the surface of the laminate is taken out as a quadric surface, assuming a tangential plane in contact with the quadric surface, the tangential plane and the A quadratic surface having a single tangent and a tangent to the quadratic surface (that is, a surface having a curvature change only in one axial direction within the surface: a surface called a developable surface in terms of differential geometry) Specifically, a conical shape, a cylindrical shape, or a part of them is applicable.

  In addition, if the textile body here can be handled as one sheet, the form will not be restrict | limited in particular, It selects from various forms, such as a nonwoven fabric, a film, a mat | matte, a mesh, a woven fabric, and a knitted fabric. be able to. Especially when it is in the form of a non-woven fabric, it is inexpensive as a material, has moderate deformability, has excellent needle permeability in the manufacturing process of molding material, has low anisotropy and has excellent handleability, and stitches This is preferable because the load on the needle can be reduced.

  Regarding (b) above, in the molding material of the present invention, the laminate is integrated by a stitch yarn comprising the second thermoplastic resin as a component and / or a textile body comprising the first thermoplastic resin as a component. Thus, excellent handling property of the molding material and excellent impregnation property when molding the FRP are brought about.

  A sheet in which a large number of reinforcing fiber yarns used in each layer of the molding material of the present invention are arranged in parallel has no woven-like structure formed. The components are easily separated. The function is performed by the textile body containing the first thermoplastic resin as a component and / or the stitch yarn containing the second thermoplastic resin as a component. This enables handling as a molding material and minimizes the effects of disturbances in handling such as misalignment, bending, and bending of reinforcing fiber yarns caused by external interference. it can.

  Moreover, when the molding material of this invention takes the aspect integrated with the said (b) stitch thread | yarn, the resin impregnation property excellent in shape | molding FRP is brought about. The resin impregnation property is different from that in the above (a) and is as described in detail below. Since the stitch yarn penetrates in the thickness direction of the laminate, a through-hole is formed in the thickness direction of the molding material, which functions as a resin flow path when the thermoplastic resin as a matrix is impregnated. Provides excellent resin impregnation. Such a through hole functions more effectively as the basis weight of reinforcing fibers per layer increases, that is, the longer the impregnation distance in the thickness direction, the more suitable this aspect.

  Further, in the case where the molding material of the present invention is laminated in multiple axes, the straightness of the reinforcing fiber yarn that is excellent when molding FRP by taking the form integrated by the stitch yarn in (b) above Bring sex. When the FRP is molded by heating and pressing the molding material, the orientation of the reinforcing fiber yarn in the molding material and the straightness are maintained even in the obtained FRP because the laminate is constrained by the stitch yarn. . The loop formed by the stitch yarn has the function of physically restricting the reinforcing fiber yarn in the molding material, so that the disturbance of the reinforcing fiber yarn induced by molding pressure or resin flow during FRP molding can be suppressed. it can.

  In the integration by the stitch yarn, it is preferable that the through holes are regularly arranged within a range of 4 to 25 rows / 25 mm in each of the longitudinal direction and the width direction of the molding material. More preferably, it is in the range of 5 to 13 rows / 25 mm in each direction. If the through hole is arranged within such a range, the stitch yarn restrains the reinforcing fiber yarn to maintain its orientation direction (angle) and straightness, and minimizes damage to the reinforcing fiber yarn. In particular, it is preferable because the uniform shapeability in molding into FRP can be expressed, and furthermore, the above-described resin impregnation properties can be combined and considered in a balanced manner. In addition, it is not necessary to arrange the through holes at the same interval in the longitudinal direction and the width direction. If you dislike shapeability, resin impregnation anisotropy, and non-uniformity when molding FRP, keep the same interval. It is preferable to arrange.

Moreover, it is preferable that the through hole has a density in the plane direction of the molding material in the range of 30,000 to 250,000 locations / m ² . More preferably, it is in the range of 60,000 to 200,000 locations / m ² , and more preferably in the range of 65,000 to 150,000 locations / m ² . When the through holes are less than 4 rows / 25 mm or less than 30,000 locations / m ² , the restraint of the reinforcing fiber yarn becomes loose, so that the handleability is inferior. Inducing bending or bending of reinforcing fiber yarns. In addition, the through-hole functions as a resin impregnation channel in the thickness direction of the molding material, and therefore the resin impregnation property may be inferior when the number thereof is reduced. On the other hand, if the through hole exceeds 25 rows / 25 mm or exceeds 250,000 locations / m ² , the resin impregnation property is excellent, but the probability that the reinforcing fiber yarn is damaged by the needle is increased. Since the amount of stitch yarn contained in the FRP increases, the mechanical properties are inferior, the effect of reducing the weight of the FRP is impaired, and the reinforcement of the reinforcing fiber yarn becomes too strong and the shapeability is inferior. There is a case.

Here, the density of the through-holes refers to a material obtained by proportionally converting the number of through-holes through which the stitch yarn penetrates in the thickness direction from a molding material cut into a square of 100 mm × 100 mm per 1 m ^2. It is easily obtained by counting the number of. The number of rows of through holes per 25 mm in the longitudinal direction or width direction of the molding material is a row in which through holes are regularly arranged in the longitudinal direction or width direction from the molding material cut into a square of 100 mm × 100 mm. Is represented to one digit after the decimal point. In order to determine whether or not the through holes are regularly arranged, the distance between the 25 through holes that are adjacent to each other in the direction of the molding material is obtained, and each distance is individually determined with respect to the average value. If the value is within ± 10%, it is judged as regular. Note that the distances between adjacent through holes do not have to be the same.

  With regard to the above (b), the molding material of the present invention may be integrated in either a textile body containing the first thermoplastic resin as a component or a stitch yarn containing the second thermoplastic resin as a component. From the viewpoint of mechanical properties and smoothness in the FRP, it is preferable that the fiber body is composed of the first thermoplastic resin as a component from the viewpoint that damage to the reinforcing fiber yarn can be minimized. From the viewpoints of material handling properties, form stability, and FRP moldability, it is preferable that they are integrated with stitch yarns containing the second thermoplastic resin as a component.

  As an embodiment in which the first thermoplastic resin is integrated from the fabric body as a component, the fabric body including the first thermoplastic resin component disposed between the sheets is heat-sealed or mechanically entangled. Although the mode of making it adhere | attach by a means is mentioned, From the viewpoint of the surface quality of FRP obtained and a mechanical characteristic, the former is preferable. The range of integration is not particularly limited. However, when handling is considered, it is preferable that the sheet is adhered over the entire surface, and as a minimum condition, the shape as a molding material can be maintained (in carrying) Extent to which the orientation of the reinforcing fiber yarn can be maintained). Examples of such integration means include a method in which a molding material containing a textile body is subjected to pressure heat treatment with a hot roller, a heating press, or the like, and a method using a hot roller that can be intermittently processed is preferable from the viewpoint of productivity. .

  Examples of an embodiment in which the second thermoplastic resin is integrated by the stitch yarn include warp knitting, weft knitting, tufting, and the like, and warp knitting is preferable from the viewpoints of both handleability and productivity.

  In addition, a molding material that is particularly excellent in shape stability when it is integrated by both the textile body having the first thermoplastic resin as a component and the stitch yarn having the second thermoplastic resin as a component. It can be. Specifically, this mode is a combination of the above-described means. For example, when needles are pierced in knitting, the sheet and the fabric body in the laminated body are mechanically bound by entanglement, and at the same time, the stitch yarns are combined. Examples thereof include a method of organizing, and a method of fusing the laminated body with a hot roller and then integrating with a stitch yarn. In particular, the former that can simplify the process is preferable from the viewpoint of productivity.

  About (c), the molding material of the present invention includes a sheet which is a spun yarn composed of discontinuous fibers having a finite length of 10 to 100 mm in the fiber length La of the reinforcing fiber yarn constituting the laminate. The 2nd shaping property in can be expressed. Here, the second formability means that when the reinforcing fiber yarn is a spun yarn, when the molding material is shaped into a predetermined shape, the single yarn constituting the reinforcing fiber yarn It is a mode in which the individual progresses and deforms in the plane direction of the sheet or is easily carried out by passing through each of them appropriately.

  Such progress deformation means that the reinforcing fiber yarn itself, that is, the single yarn constituting the spun yarn, is pulled or straightened in the reinforcing fiber yarn, so that the reinforcing fiber yarn itself is stretched and deformed. This corresponds to the deformation of the molding material due to this. Carbon fibers and glass fibers can be mentioned as reinforcing fibers suitably used for FRP, but these reinforcing fibers have a low elongation, so when trying to shape them into a single contour shape or a double contour shape, reinforcing fiber yarns Will be stretched and cannot follow the desired shape, or wrinkles will occur. If it is a single contour shape, it is possible to alleviate this problem due to the development of the first formability described above. However, when it becomes a double contour shape, it will be shaped only by the shapeability in the thickness direction of the molding material. Therefore, deformation of the molding material in the plane direction is required. Even if shear deformation is caused in the plane direction of the molding material, there is a limit to this, and the amount of deformation is limited as the orientation axis of the reinforcing fiber yarn increases, so that the effect cannot be expected in a multiaxially oriented material. . On the other hand, since the reinforcing fiber yarn is a spun yarn when the molding material takes the form (c), the reinforcing fiber yarn is stretched and deformed even when trying to form a double contour shape. Thus, there is no worry that the reinforcing fiber yarn is stretched, and even if it is multiaxially oriented, the reinforcing fiber yarn is stretched and deformed, so there is no restriction in the orientation direction of the reinforcing fiber yarn, and in the plane direction of the molding material A synergistic effect with shear deformation can be achieved.

  The double contour shape referred to in the present invention is a point on the quadric surface when the surface of the laminate is taken out as a quadric surface, and any plane passing through the point can be referred to. A curved surface shape including at least a portion where an intersection line passing through the point becomes a curved line among intersection lines of the plane and the quadric surface. Specifically, a saddle shape, a hemispherical shape, a flat plate having an uneven portion, and the like are applicable, but a flat plate without an uneven portion, a conical shape, and a cylindrical shape are not applicable.

  Here, the spun yarn refers to a bundle of discontinuous fibers, and the shape is not particularly limited as long as it can be handled as a yarn, and may include a twist, or substantially It may be a non-twisted one, and may be held in a yarn form by covering and binder, or a combination thereof. Such spun yarn may be spun from discontinuous fibers (for example, cotton spinning) or spun from continuous fibers (tow) (for example, check spinning, linear spinning). However, the latter is preferable in that the process is simple and equipment costs and processing costs can be reduced. Among the latter, spun yarn (check-cut spinning) manufactured by the check-spinning method provides spinning to the reinforcing fiber yarn made of continuous fibers and checks the continuous single fiber in the yarn. Therefore, from one of the reinforcing fiber yarns, a plurality of reinforcing fiber yarns can be drawn in parallel and spun in the same manner from tape-shaped or sheet-shaped in advance. That is, it can be obtained as a check thread, a check tape and a check sheet, and in any form, it can be put in the sheet forming means constituting the laminate. Especially, it is preferable to take the form of a check sheet from a viewpoint of processing cost.

  The above (c) includes spun yarns composed of discontinuous fibers having a finite length in which the fiber length La of the reinforcing fiber yarns constituting the laminate is 10 to 100 mm. More preferably, the spun yarn is composed of discontinuous fibers having a finite length within a range of 30 to 70 mm. By including a spun yarn composed of such a finite length of discontinuous fibers, it is possible to achieve both the handleability and the shapeability of the molding material.

  Within such a range, the discontinuous fiber has a finite length, that is, the fiber length La, so that both the handling property and the shapeability of the molding material can be improved. If the fiber length La of the discontinuous fiber is less than 10 mm, the fiber length is too short. Therefore, when trying to form a spun yarn, it is necessary to increase the number of twists and the amount of the binder, and as a result, it is difficult to express stretch deformation. Even if the spun yarn can be formed in a state that is not so, discontinuous fibers fall off from the molding material, or even if a slight force is applied, deformation is induced, so as a molding material It becomes difficult to handle.

  Regarding (d), at least 50% or more of the reinforcing fiber yarns constituting the laminate are composed of discontinuous fibers having a finite length in which the fiber length La of the reinforcing fiber yarns constituting the laminate is 10 to 100 mm. Spun yarn. When the proportion of the reinforcing fiber yarn is a spun yarn, the shapeability in the molding material can be effectively extracted.

  As described above, the shapeability of the molding material of the present invention is a synergistic effect between the shear deformation between the layers which is the first shapeability and the progress deformation within the layer which is the second shapeability, Regarding the shapeability in the in-plane direction, the contribution of the second shapeability is large.

  However, a molding material composed of continuous fibers does not have no formability in the plane. As an example, it is a bi-directional woven fabric, and when the woven fabric is stretched in the non-fiber direction, the phenomenon that the structure is deformed from a square to a rhombus. In this specification, this phenomenon is called in-plane shear deformation.

  Such in-plane shear deformation is a change in the shape of the components in the plane, and brings about shaping by absorbing strain by converging reinforcing fiber bundles, closing gaps, and densifying tissues. In addition, there is a limit to deformation, and the space is dense (there is no room for deformation in the plane). Theoretically, the reinforcing fiber bundles converge in a perfect circle and close It is in a state of being.

  On the other hand, in the case of a molding material composed of spun yarn, the limit point in the in-plane shear deformation can be raised from that of continuous fibers. As described above, the fiber bundle is limited to a state of being converged in a perfect circle, but this is a case of continuous fibers, that is, the number of single yarns in the fiber bundle cross section is absolute. However, in the case of a spun yarn, the individual yarns constituting the spun yarn can be pulled or straightened in the reinforcing fiber yarn, whereby the reinforcing fiber yarn itself can be stretched and deformed, that is, Since the number of single yarns in the fiber bundle cross section is variable, it can still be deformed even when the theoretical limit is reached. Thus, raising the limit of deformation is the essence of the above (d), and as a result of intensive studies, at least 50% or more of the reinforcing fiber yarns constituting the laminate are spun yarns. It has been found that the above effects can be fully expressed.

  Each of the sheets constituting the laminate is laminated in a multiaxial orientation so that the reinforcing fiber yarns intersect to constitute a laminate, the number of axes to be oriented is n-axis, and the fiber length La is 10 When the weight ratio in the molding material of the spun yarn composed of discontinuous fibers having a finite length of ˜100 mm is N%, it is preferable that n and N satisfy the relationship of the following formula.

(100-100 / n) ≦ N (1)
By satisfying the formula (1), it is possible to control the shapeability and mechanical properties of the molding material with a good balance. As specific modes satisfying the formula (1), there are the following two modes. The effects that can be expected in each aspect will be described in detail below, but may be properly used depending on the shape and design of the target molded body.

  As a 1st aspect which satisfy | fills this (1) type | formula, all the reinforcing fiber yarns which comprise a 90 degree sheet | seat among the molding materials in which the reinforcing fiber yarns were orientated (0 degree / 90 degrees) are fibers. The spun yarn is composed of discontinuous fibers having a finite length of 10 to 100 mm in length La. In such a case, when the weights per unit area of 0 ° and 90 ° are equal (total), N = 50, and the weight per unit area of 90 ° sheets composed of spun yarns (total of ) Is greater than the weight per unit area (total) of the 0 ° sheet composed of continuous fiber yarns, 50 <N.

  As for the molding material obtained from this, since only the 90 ° sheet is composed of the spun yarn, the second formability is also given only to the 90 ° sheet. If it is a shape that only requires a curvature, it can be shaped, and in the 0 ° direction, it can be expected to exhibit the same strength as a continuous fiber. This is the same even when the fiber orientation axis is increased, and can be obtained by applying the spun yarn to all the sheets except the sheet having a specific orientation in the laminate. That is, all the sheets except the sheet of specific orientation in the laminate are spun yarns composed of finite length discontinuous fibers having a fiber length La of 10 to 100 mm. Sex can be selectively imparted and the mechanical properties of FRP can be maximized.

  As a 2nd aspect which satisfy | fills the said (1) type | formula, in each of the sheet | seat of the molding material in which the reinforcing fiber yarn was orientated (0 degree / 90 degree), fiber length La is 10-100 mm in finite length. It includes spun yarn composed of discontinuous fibers. In this case, n is biaxial and N ≧ 50. Also in the second aspect, it is preferable that the weight ratio N of the reinforcing fiber yarn that is cut with a finite length of 10 to 100 mm satisfies the formula (1).

  In such a molding material, some of the spun yarn is contained in all the sheets constituting the laminate, and the second formability is somewhat exhibited in all the sheets. Alternatively, even if the effect of the second formability is not sufficient, the above-described in-plane shear deformation is exhibited, so that the formability as a molding material is sufficiently ensured. In addition, since the ratio of the remaining continuous fibers or the fiber length La of the discontinuous fibers constituting the spun yarn can be controlled for each sheet, it is possible to take a prescription that also takes into account the anisotropy of physical properties in FRP. it can. That is, the physical properties of the molding material can be made uniform and anisotropy can be imparted, but in particular, this is a preferred embodiment in view of the balance of all sheets of the molding material. Therefore, preferably, the weight ratio of the spun yarn composed of discontinuous fibers having a finite length of 10 to 100 mm in fiber length La is the same at N% or more for each sheet, and the molding material obtained therefrom is homogeneous. Excellent in properties.

  Hereinafter, the molding material of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic perspective view showing one embodiment of the molding material of the present invention.

  As shown in FIG. 1, the molding material 1 is composed of a plurality of layers of a sheet in which a large number of reinforcing fiber yarns are aligned in parallel, and is formed of a sheet in which the reinforcing fiber yarns 2 are aligned in parallel at 0 °. A first layer, a second layer composed of a sheet in which the reinforcing fiber yarns 2 are aligned in parallel at 90 °, a third layer composed of a sheet in which the reinforcing fiber yarns 2 are aligned in parallel at α °, and a reinforcing fiber A total of four layers are laminated with a fourth layer (outermost layer) made of sheets in which the yarns 2 are aligned in parallel with -α °, and a fabric body (nonwoven fabric) 3 is arranged between each layer and laminated. It forms a body and is integrated by stitch yarns 4 penetrating in the thickness direction of the laminate. All of the reinforcing fiber yarns 2 in the molding material 1 are spun yarns. The stitch yarn structure in FIG. 1 is an irregular 1/1 tricot knitting in which a chain knitting and a 1/1 tricot knitting are combined. However, a chain knitting or a 1/1 tricot knitting may be used. If it can penetrate and be integrated, a desired tissue can be obtained. As shown in FIG. 1, when the reinforcing fiber yarns are oriented at 0 ° in the first layer (outermost layer), a structure having stitch yarns in the direction intersecting with the longitudinal direction of the molding material such as tricot knitting. By doing, it is preferable because it can prevent the reinforcing fiber yarn from falling off the surface. Here, the reinforcing fiber yarn direction (0 ° direction) 5 in the first layer, the direction 6 in which the stitch yarn 4 extends, and the longitudinal direction 7 of the molding material are the same direction, and any direction below. Shall also accompany this.

  Here, it is preferable that the fineness of the spun yarn used for the molding material of the present invention is 300 to 5,000 tex, and the yarn width W / yarn thickness T is 2 to 20. In such an embodiment, the surface irregularity of the molding material and the FRP obtained therefrom can be reduced because it is flat despite the thick reinforcing fiber yarn.

  When the fineness of the spun yarn is less than 300 tex, the fineness is too small and a large number of reinforcing fiber yarns may be required. When the fineness of the spun yarn exceeds 5,000 tex, the fineness is too large and the yarn width of the reinforcing fiber yarn is reduced. It can be difficult to control. In addition, when the yarn width W / yarn thickness T of the spun yarn is less than 2, the cross-sectional shape of the spun yarn is close to a circle, so that the unevenness in the sheet becomes large. The unevenness may be transferred, and the surface unevenness may become very large in the molding material. On the other hand, when the yarn width W / yarn thickness T of the spun yarn exceeds 20, it becomes difficult to maintain the shape of the flat yarn, and yarn cracking may occur. From such a viewpoint, when the fineness of the spun yarn is 300 to 5,000 tex and the yarn width W / yarn thickness T is in the range of 2 to 20, an excellent quality molding material can be obtained. From the viewpoint of surface smoothness and design properties, an excellent effect is brought about.

  The yarn width W and the yarn thickness T are measured in a state in which the cross-sectional shape of the reinforcing fiber yarn is not changed from the molding material. The measurement method may be a contact type using a caliper, a micrometer, etc., but preferably the non-contact type measurement using a displacement sensor or the like because the cross-sectional shape of the thread is likely to change during measurement. It is. Here, regarding the yarn width W and the yarn thickness T, the minimum diameter in the cross section of the extracted yarn is the yarn thickness T, and the maximum diameter is the yarn width W.

  Moreover, as another preferable aspect in this invention, it is that the twist number of the said spun yarn exists in the range of 5-200 turns / m. When the number of twists is within such a range, it is possible to achieve both a minimum form retention as a spun yarn and a function of stretching deformation. If the number of twists is too small, it will be difficult to maintain the shape as a spun yarn, so the processability and handleability of the molding material will be inferior. If the length becomes long and as a result, the shapeability cannot be fully exhibited and the number of twists is too large, the spun yarn has excellent shape stability, but the resistance when the spun yarn is stretched and deformed increases, and the shape is At this time, excessive pressure is required, and as a result, the formability may be impaired. From this point of view, the number of twists of the spun yarn used in the present invention is preferably within a range of 5 to 200 turns / m, and if within this range, both the handleability and the formability of the molding material are impaired. Can coexist without any problems.

  Furthermore, as another preferred embodiment of the present invention, the spun yarn composed of discontinuous fibers is substantially untwisted and is covered and covered with auxiliary fiber yarns. Covering in an untwisted state, that is, since it is not twisted, it is possible to easily flatten the yarn, and if the covering yarn is a thermoplastic resin fiber, in the covering state By heat melting, the shape of the yarn can be maintained in a flat state. Here, when the covering yarn made of the second thermoplastic resin of the present invention is used as the covering yarn, it can be composed of the same resin as the thermoplastic resin used as the matrix, so that both are excellent in compatibility. In particular, excellent mechanical properties can be exhibited. Here, “substantially no twist” means less than 1 turn / m.

In the molding material of the present invention, the melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy the following relationships (e) to (g): In the molding of FRP and the obtained FRP, excellent effects are brought about respectively.
(E) The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin are (Tm1-150) ≦ Tm2 ≦ (Tm1-20).
(F) The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin are ((Tm2-150) ≦ Tm1 ≦ (Tm2-20).
(G) The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin are (Tm2-20) <Tm1 <(Tm2 + 20).
When the melting points of the first thermoplastic resin and the second thermoplastic resin are in the relationship (e), the stitch yarn can be melted first when molding the FRP. Before impregnation into the fiber yarn layer, the stitch yarn is restrained in the thickness direction of the molding material, so that it is particularly easy to shear between the layers. In the relationship of (e), the function of the stitch yarn is not lost at all, but the stitch yarn that has been melted first changes its form and remains in the thickness direction and the plane direction of the molding material. It is possible to prevent the yarns from cracking in the plane direction and to suppress the bending of the reinforcing fiber yarns from being significantly bent. Therefore, even when shaping into a complicated shape, it can be shaped while suppressing wrinkles generated in the molding material. That is, it can be said that the molding material satisfying the relationship (e) is a mode specialized for shear deformation between layers of the molding material. Since it has such a feature, a single contour shape (for example, a cylindrical shape, an arch) Shape). In the relationship of (e), when a plurality of molding materials are laminated, the stitch material composed of the second thermoplastic resin is partially melted without melting the textile body and the molding materials are integrated. Therefore, it can be said to be a preferred embodiment in the present invention.

  As a specific combination satisfying the relationship (e), for example, the first thermoplastic resin is polyamide 6 or polyamide 66, and the second thermoplastic resin is polyamide 11, polyamide 12 or copolymer polyamide ( For example, polyamide 6/66/12, polyamide 610/12, polyamide 6/66/610/12, polyamide 6/66/612/12, and the like, and the first thermoplastic resin is polyamide 66, The combination in which the second thermoplastic resin is polyamide 6, the first thermoplastic resin is polyester, the second thermoplastic resin is a copolymerized polyester, and the first thermoplastic resin is polyethylene or polypropylene A combination in which the second thermoplastic resin is a copolymerized polyolefin, and the first thermoplastic resin is polypropylene. , And the second thermoplastic resins are combinations is ethylene. In the case of the above combination, the first thermoplastic resin and the second thermoplastic resin are composed of resins having a similar molecular structure, so that both are excellent in compatibility and exhibit excellent mechanical properties in FRP. Can do.

  In addition, when the first thermoplastic resin is polyphenylene sulfide and the second thermoplastic resin is a combination of polyamide, the difference in melting point between the first thermoplastic resin and the second thermoplastic resin is increased. It has the advantage that it is particularly excellent in formability.

  When the melting points of the first thermoplastic resin and the second thermoplastic resin are in the relationship (f), when the FRP is molded by heating the molding material, the textile body that is the first thermoplastic resin is While the first thermoplastic resin is impregnated in the reinforcing fiber yarn layer in order to melt first, each layer constituted by the reinforcing fiber yarn is formed by the stitch yarn which is the second thermoplastic resin. Since it is restrained, the orientation of the reinforcing fiber yarn can be particularly restricted. Further, since the stitch yarn penetrates in the thickness direction of the molding material, the through hole becomes an impregnation flow path for the resin, and there is also an effect of remarkably improving the impregnation property of the melted first thermoplastic resin. . In addition, the improvement of the impregnation property by the through hole is achieved regardless of whether or not the stitch yarn is melted, and also in the relationship of the above (e) and the later (g) in which the stitch yarn is melted. Since the melted stitch yarn changes its form and exists in the through hole, the through hole remains and functions as an impregnation channel. In this embodiment (f) where the stitch yarn is not melted, the shape of the through-hole is completely maintained by the stitch yarn remaining as a thread, and the function as the impregnation channel is more efficiently performed. In this embodiment (f), such an effect is particularly greatly manifested.

  In addition, in relation to (f), the fabric body (nonwoven fabric) 12 is inserted as shown in FIGS. 3 and 4 in order to melt the fabric body first and impregnate each layer with a thermoplastic resin as a matrix. Further, the thickness between the layers is reduced, the constraint of the stitch yarn 13 is loosened, and the frictional resistance between the respective layers is reduced, so that the shear deformation is easily performed between the layers. For this reason, the generation of wrinkles is suppressed even in the formation of a curved surface, and the orientation of the reinforcing fiber yarn is maintained by the presence of the stitch yarn, so that a high-quality FRP that can exhibit excellent mechanical properties is obtained. be able to. That is, it can be said that the molding material satisfying the relationship (f) is an aspect in which both the ease of shear deformation between the layers of the molding material and the restraint of the reinforcing fiber yarn by the stitch yarn are compatible. Therefore, it is preferably shaped into a double contour shape (for example, a hat shape) having a relatively gentle curved surface or a large area and a thin shape. In this relationship (f), when the fabric body composed of the first thermoplastic resin is disposed on at least one of the outermost layers of the molding material, the stitch yarn is not melted when the plurality of molding materials are laminated. Since the outermost layer body is partially melted and the molding materials can be integrated (for example, a form of a preform), it can be said to be a preferable aspect in the present invention. FIG. 4 is a schematic view for easy understanding of the state where the stitch yarn is loosened. When the fabric (nonwoven fabric) is actually melted, the stitch yarn is in a loose state. Even if it exists, it is immersed in the thermoplastic resin used as a matrix.

  As a specific combination satisfying the relationship (f), for example, the first thermoplastic resin is polyamide 11, polyamide 12 or copolymer polyamide (for example, polyamide 6/66/12, polyamide 610/12, polyamide). 6/66/610/12, etc.), and the second thermoplastic resin is polyamide 6 or polyamide 66, or the first thermoplastic resin is polyamide 6, and the second thermoplastic resin is polyamide. 66, the first thermoplastic resin is a copolyester, the second thermoplastic resin is a polyester, the first thermoplastic resin is a copolyolefin, and the second thermoplastic resin is a copolyester. A combination that is polyethylene or polypropylene, the first thermoplastic resin is polyethylene, and the second thermoplastic resin is poly The combination and the like is propylene. In the case of the above combination, when a resin similar to the first thermoplastic resin and the second thermoplastic resin is used, the adhesiveness between the two is excellent, and thus excellent mechanical properties can be expressed. In addition, when the first thermoplastic resin is a polyolefin and the second thermoplastic resin is a combination of polyester, the difference in melting point between the first thermoplastic resin and the second thermoplastic resin can be increased. Since it can be easily impregnated, there is an advantage of excellent moldability.

  From another point of view, if the melting points of the first thermoplastic resin and the second thermoplastic resin are in the relationship (g), the stitch yarn and the fabric body are melted almost simultaneously when the FRP is formed. Can do. The molding material of this aspect has an intermediate characteristic between the above (e) and (f), and as a particularly excellent point, heating during molding can be performed in one step, and the molding cycle can be shortened. . Moreover, it can shape | mold so that most traces of a stitch thread | yarn may not be left by heating of 1 step, and FRP excellent in surface smoothness can be obtained. Furthermore, since the first thermoplastic resin and the second thermoplastic resin can be made of the same resin, they are excellent in compatibility and can exhibit particularly excellent mechanical properties in FRP.

  As described above, the molding material of the present invention may be arbitrarily selected in a mode that satisfies any one of the relationships (e) to (f) according to the desired FRP form.

  Here, melting | fusing point refers to the value measured by DSC (differential scanning calorimeter) based on JISK7121 (1987) at the temperature increase rate of 20 degrees C / min in the absolutely dry state. In the present invention, the glass transition temperature + 100 ° C. obtained by the above measuring method is simply regarded as the melting point for those that do not exhibit a melting point (for example, an amorphous polymer).

Here, the basis weight of the reinforcing fibers in each sheet constituting the molding material of the present invention is preferably in the range of 50 to 350 g / m ² .

When the basis weight of the reinforcing fiber is within such a range, an excellent surface product and formability are exhibited in the molding material. When the basis weight of the reinforcing fiber in each layer is less than 50 g / m ² , a gap (gap) is formed between adjacent reinforcing fiber yarns, resulting in inferior quality when FRP is used, and deterioration in mechanical properties. There are concerns such as. On the other hand, if the basis weight of the reinforcing fibers in each layer is larger than 350 g / m ² , a portion where adjacent reinforcing fiber yarns overlap with each other is generated. This may increase the shapeability and impregnation properties. Regarding the impregnation property, excessive pressure is required to melt and completely impregnate the sheet of thermoplastic resin in each sheet, and the excessive pressure induces bending of the reinforcing fiber yarn. There is a case.

Moreover, it is preferable that each fabric weight of the textile body arrange | positioned between the said sheets is the range of 15-250 g / m < ² >. More preferably, it is 35-150 g / m < ² >, More preferably, it is 40-100 g / m < ² >.

If the fabric weight is less than 15 g / m ² , the amount of the thermoplastic resin is relatively insufficient with respect to the amount of the reinforcing fiber yarn, so that it cannot be sufficiently impregnated, and the fabric body becomes too thin. Problems such as tearing or deformation in the manufacturing process of the molding material are likely to occur, and the handleability of the fabric body is significantly reduced. From the same viewpoint, it is more preferably 35 g / m ² or more, further preferably 40 g / m ² or more. In order to avoid this problem, if the basis weight of the reinforcing fiber in each sheet is lowered beyond the range of the present invention, a gap is formed between the reinforcing fiber yarns, so that not only the strength when FRP is reduced but also the quality. May get worse. On the other hand, if the basis weight of the textile body exceeds 250 g / m ² , the content of reinforcing fibers is relatively reduced, and sufficient strength cannot be expressed when FRP is used. In order to avoid this problem, if the basis weight of the reinforcing fiber of each sheet is increased beyond the scope of the present invention, the reinforcing fiber yarns overlap each other, resulting in unevenness on the surface, not only inferior formability and quality, When impregnating the resin, an excessive external pressure is required, and the reinforcing fiber yarn may be bent.

  In addition, the basis weight of the reinforcing fiber yarn and the fabric body of each sheet is cut out in accordance with JIS R7602 (1989) 5.5, the local material is released, the molding material is disassembled, and each sheet is disassembled. It is set as the value measured about the reinforcing fiber and fabric body.

  Examples of the reinforcing fiber yarn used in the present invention include carbon fibers, graphite fibers, glass fibers, and organic fibers such as aramid, paraphenylenebenzobisoxazole, polyvinyl alcohol, polyethylene, polyarylate and polyimide, These 1 type (s) or 2 or more types can be used together. Among these, carbon fibers are preferably used because they are excellent in specific strength and specific elastic modulus and effective in reducing the weight of the FRP molded product. As the carbon fiber, the tensile strength of the yarn is preferably 4 GPa or more and 7 GPa or less, more preferably 4.5 GPa or more and 6.5 GPa or less, and the tensile elastic modulus is 200 GPa or more and 500 GPa or less, particularly suitable for a structural material. . The tensile strength of the yarn can be determined according to a tensile test method specified in JIS R-7601 after impregnating a carbon fiber yarn with a resin having the following composition and curing at 130 ° C. for 35 minutes. The resin composition is alicyclic epoxy resin (3,4-epoxycyclohexylmethyl-3,4-epoxy-cyclohexyl-carboxylate): 100 parts by weight, boron trifluoride monoethylamine: 3 parts by weight, acetone: 4 weights Part. Further, the tensile elastic modulus of the yarn can be obtained from a slope of a load-elongation curve by performing a tensile test in the same manner as the above-described tensile strength measuring method.

  The reinforcing fiber yarn is preferably attached with 0.2 to 2.5% by weight of a sizing agent from the viewpoint of handleability and resistance to needle abrasion during knitting. Generation | occurrence | production of fluff can be suppressed because the sizing agent adheres in the said range.

The reinforcing fiber yarns may be either untwisted yarns or twisted yarns, but are preferably substantially untwisted (less than 1 turn / m) from the viewpoint of mechanical properties such as tensile strength and compressive strength. From this point of view, in the production of the molding material of the present invention, the reinforcing fiber yarn may be warped and untwisted to mix the untwisting twist, but the twisting and untwisting will not cause untwisting. The reinforcing fiber yarn is preferably present in the molding material in a substantially untwisted state (less than 1 turn / m). With this weft removal, not only a high-quality sheet can be easily obtained in the reinforcing fiber basis weight within the scope of the present invention, but also the reinforcing fiber volume ratio (Vf) and mechanical properties can be improved as FRP. . In particular, when the basis weight of the sheet is 190 g / m ² or less, a gap (gap) between the reinforcing fiber yarns is easily formed in the sheet, and the sheet quality may be inferior. The above effect is more markedly manifested when the fineness of the reinforcing fiber yarn is within the following range. The fineness of the reinforcing fiber yarn is preferably 500 to 7,000 tex, more preferably 1,000 to 2,000 tex. If the fineness is too small, the effect of the present invention may not be exhibited because there is almost no influence due to the mixing of the twist, the fiber yarn becomes expensive, and a large number of fine fiber yarns with fineness are used. Therefore, the multiaxial base material itself becomes expensive. On the other hand, when the fineness is too large, for example, when obtaining a molding material having a low basis weight of reinforced fiber yarns per layer of 100 g / m ² or less, the yarn width is likely to fluctuate with a slight force and is stable. It may be difficult to maintain the yarn width.

  The molding material of the present invention can exhibit its excellent shapeability to the maximum by forming one or more of the molding materials into a preform formed into at least a single contour shape or a double contour shape. it can. FIG. 2 is a schematic cross-sectional view of a preform obtained by shaping the molding material of the present invention into an arch shape.

  As shown in FIG. 2, the molding material 8 of the present invention is shaped into a mold having an arch shape (not shown), and the molding material 8 is shear-deformed in the thickness direction so that it is located on the surface of the mold. The difference between the inner and outer peripheral lengths from the inner peripheral portion to the outer peripheral portion is alleviated, and generation of wrinkles is suppressed. Further, when attention is paid to each sheet 9 constituting the molding material, the reinforcing fiber yarn (spun yarn) 10 is stretched and deformed in each sheet, thereby releasing the distortion in the plane direction of the molding material 8. And is shaped along the mold. That is, due to the mutual synergistic effect of the first shapeability and the second shapeability in the molding material, even in the single contour shape or the double contour shape, the wrinkles and reinforcing fiber yarns are not stretched. A preform along a desired shape can be obtained.

  In addition, in a portion where the molding material is shaped into a single contour shape or a double contour shape, the arc length Lc and the fiber length La in each cross section in the reinforcing fiber yarn direction of each sheet constituting the molding material are Lc>. La is preferred. Here, each cross section in the reinforcing fiber yarn direction of each sheet constituting the molding material is cut out along the direction in which the reinforcing fiber yarns are aligned in parallel in each sheet forming the molding material The length Lc of the arc is the length of a line segment in contact with the molding material in the shape of the cross section, and the fiber length La is a reinforcing fiber that is aligned in the same direction as the cross section. The fiber length of the yarn. In addition, since there are an infinite number of cross sections in the shape, it is only necessary to satisfy the above aspect for an arc that is within 1/10 of the length Lc of the largest arc in the shape to be shaped.

  In such an embodiment, since the reinforcing fiber yarn is cut at a distance shorter than at least the arc, the free end of the reinforcing fiber yarn is always disposed on the mold to be shaped. It is possible to develop the second formability in the molding material without stretching. That is, in this aspect, it is possible to express the shaping property of the molding material described above without being influenced by the shape to be shaped. For this reason, Lc> La. Since La is in the range of 10 to 300 mm as described above, the lower limit value is La = 10 mm, and when Lc <10 mm, there is a slight change in shape, which is caused by the free ends of the nearby reinforcing fiber yarns. Since it is relaxed, there is no particular problem even if it is outside the range of Lc> La.

  The FRP of the present invention is formed by using the above-mentioned molding material or preform, and is a matrix resin obtained by melting and solidifying at least the first thermoplastic resin constituting the fabric body. is there.

  If the molding material or preform of the present invention is integrated with the textile body to be the matrix in advance, the step of injecting the matrix resin like RTM can be omitted, so the molding cycle can be shortened and the FRP productivity can be shortened. Excellent. In addition, when the molding material or preform of the present invention is used, it can be shaped into a single contour shape or a double contour shape while suppressing the generation of wrinkles, and an FRP in which the disturbance of the orientation of the reinforcing fiber yarn is suppressed is molded. can do.

  In the case of using the above-mentioned (e) thermoplastic body and stitch yarn, such FRP is obtained by first melting the stitch yarn containing the second thermoplastic resin as a component and then the first heat. Since the textile body containing the plastic resin as a component is melted and solidified to form a matrix, the FRP has no trace of stitch yarn. And as above-mentioned, even if it is a complicated shape, it can shape | mold while suppressing wrinkles, As a result, it can be set as FRP excellent in surface smoothness and a mechanical characteristic. Further, when forming and forming a preform by laminating a plurality of molding materials, the molding materials can be integrated in advance, so that the molding cycle is short and the productivity is excellent.

  Further, in the case of using the fabric body and the stitch yarn having the thermoplastic resin component (F) as a component, the fabric body having the first thermoplastic resin component is melted and solidified to form a matrix. The stitch yarn containing the thermoplastic resin of 2 as an ingredient becomes an FRP that substantially maintains its form, and as described above, the disorder of the orientation of the reinforcing fiber yarn is suppressed by the stitch yarn that is not melted, The FRP can exhibit excellent mechanical properties.

  Furthermore, when the textile body and the stitch yarn containing the thermoplastic resin of the above aspect (g) are used, the textile body containing the first thermoplastic resin and the second thermoplastic resin are used as components. The stitch yarn and FRP are simultaneously melted and solidified to form a matrix. Thereby, as above-mentioned, a shaping | molding cycle can be shortened and it can be set as FRP excellent in surface smoothness and a mechanical characteristic.

  In the production of such FRP, means for heating and pressurizing the molding material is not particularly limited, but it is preferable to use an autoclave, a combination of an oven and atmospheric pressure, a press machine, etc. A press is more preferable because of its speed.

The following were used as raw materials in the examples and comparative examples.
<Reinforcing fiber yarn>
PAN-based carbon fiber yarn, 12,000 filaments, fineness 800 tex, tensile strength 4,900 MPa, tensile elastic modulus 240 GPa, 0 turns / m.
<Stitch yarn>
Stitch yarn A: Copolymerized polyamid (“Elder” (registered trademark), manufactured by Toray Industries, Inc.), 10 filaments, fineness 56 dtex, melting point 115 ° C.
Stitch yarn B: Polyamide 66, 10 filament, fineness 33 dtex, melting point 255 ° C.
<Textile body>
Nonwoven fabric A: Polyamide 6, basis weight 80 g / m ² , melting point 220 ° C.
Nonwoven fabric B: copolymerized polyamide (manufactured by Toray Industries, Inc., “Elder” (registered trademark)), basis weight 80 g / m ² , melting point 115 ° C.
Nonwoven fabric C: Polyamide 6, basis weight 33 g / m ² , melting point 220 ° C.
<Molding material>
Thereafter, a molding material having a width of 1.27 m was produced by the procedures (1) to (6).

First, the laminated body which has the nonwoven fabric A between each sheet | seat comprised with the reinforced fiber yarn and any outermost layer was formed.
(1) The nonwoven fabric A arranged in the outermost layer was continuously supplied so that the longitudinal directions of the nonwoven fabric A and the belt conveyor were parallel. The belt conveyor continues to move in the longitudinal direction (0 ° direction) at a constant speed of 1 m / min during the subsequent lamination of the reinforcing fiber yarn layer and the nonwoven fabric, and continuously to the adhesive means described later. It is to be transported.
(2) On the nonwoven fabric A, the reinforcing fiber yarns that have been weaved and unwound so as not to mix the untwisted strands are aligned in parallel to the longitudinal direction (0 ° direction) at −45 °, and A -45 ° sheet was formed by arranging so that the basis weight of the reinforcing fibers per layer was 150 g / m ² . The arrangement of the reinforcing fiber yarns of the −45 ° sheet was performed by a carriage device. The carriage device in this process reciprocates in the -45 ° direction, and is a device that arranges reinforcing fiber yarns on the belt conveyor during the forward movement (or backward movement), and the belt conveyor is longitudinal. The reinforcing fiber yarns are controlled so as to be adjacent to each other in parallel without being overlapped with each other in synchronization with the speed of conveyance in the direction.
(3) The second nonwoven fabric A is placed on the −45 ° sheet, and the reinforcing fiber yarns are parallel to the longitudinal direction at + 90 ° with respect to the longitudinal direction in the same manner as in the −45 ° sheet formation. And a + 90 ° sheet was formed so as to be 150 g / m ² .
(4) A third non-woven fabric A is placed on the + 90 ° sheet, and the reinforcing fiber yarns are parallel to the longitudinal direction at + 45 ° in the same manner as in the −45 ° sheet formation. And it arranged so that it might become 150 g / m < ² >, and the +45 degree sheet | seat was formed.
(5) The fourth nonwoven fabric A is arranged on the + 45 ° sheet layer, and the reinforcing fiber yarns are parallel to the longitudinal direction at 0 ° in the same manner as in the −45 ° sheet formation. And a 0 ° sheet was formed by arranging so as to be 150 g / m ² .
(6) The 5th nonwoven fabric A was arrange | positioned on the said 0 degree sheet | seat, and the laminated body was formed.
Subsequently, the laminate on the belt conveyor formed as described above was integrated by stitching with the stitch yarn A. In such stitches, the stitch yarn A was unwound by an unwinding device and knitted while allowing the needle to penetrate the laminate. The knitting structure of the stitch yarn is an irregular 1/1 tricot knitting that combines a chain knitting and a 1/1 tricot knitting, and the through holes by the stitch yarn are 8.3 rows / 25 mm in the longitudinal direction of the molding material, and the width direction (Wb). Regularly arranged to be 5 rows / 25 mm. The density of the through holes was 66,666 places / m ² . Nonwoven fabric A was excellent in needle penetrability, and the fibers of the nonwoven fabric were not entangled with the needle. The molding material integrated with the stitch yarn A was wound as a blank by a winding device.

(Example 1)
Of the molding material (blank) produced by the procedure of (1) to (6), the spun yarn A is used in 100% of the reinforcing fiber yarns constituting each of the −45 ° sheet, 90 ° sheet and + 45 ° sheet. Was used to obtain a molding material A. The spun yarn A (fineness: 800 tex) is obtained by twisting a discontinuous fiber obtained by cutting a reinforcing fiber yarn into a fiber length La = 50 mm into a yarn by twisting at a twist number = 100 turns / m. The flattening process was performed so that the thread width / thread thickness = 10.

  In the obtained molding material A, 75% of the reinforcing fiber yarns consisted of discontinuous fibers, and the handling property was retained by the twisting process, and the form as the spun yarn was retained, and was restrained by the stitch yarn. It was a level that could be handled sufficiently as a molding material.

  The obtained molding material A was placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape having a radius of curvature of 305 mm, and the preform was pressed. Obtained.

  The obtained preform was a good preform without the occurrence of wrinkles by releasing the in-plane distortion of the molding material by discontinuing discontinuous fibers constituting the spun yarn.

  Further, the obtained preform was placed again on the mold, and once heated to 150 ° C., the stitch yarn A was allowed to follow the mold while being melted, and pressed (pressed) at 25 MPa for 180 seconds. While being pressurized, the mold temperature was raised to 250 ° C. and held for 180 seconds, the mold temperature was cooled to 50 ° C., and then the pressure was released and demolded to obtain FRP.

  When the cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and the observation surface of the void is slightly seen near the outermost layer 96% of the resin was impregnated with resin. In addition, the occurrence of wrinkles was observed only when the fiber orientation was slightly disturbed, and since the flattening treatment was performed so that the yarn width / thickness ratio was 10, the surface smoothness was excellent. It was.

(Example 2)
Of the molding material (blank) produced by the procedures (1) to (6), the spun yarn B is used for 100% of the reinforcing fiber yarns constituting the −45 ° sheet, 90 ° sheet, and + 45 ° sheet. Thus, molding material B was obtained. In this spun yarn B, a discontinuous fiber obtained by cutting a reinforcing fiber yarn into a fiber length La = 50 mm is covered at a rate of 200 turns / m using a covering yarn similar to the stitch yarn A in a non-twisted state. After flattening so that width / yarn thickness = 10, the covering yarn was melt bonded to maintain the shape.

  In the obtained molding material B, 75% of the reinforcing fiber yarns are composed of discontinuous fibers, and the handling property is stably maintained as a spun yarn due to the binder effect of the covering yarn. Excellent handleability.

  The obtained molding material B was placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and then placed between the female molds of the same shape having a radius of curvature of 305 mm. The stitch yarn A and the covering yarn were allowed to follow the mold while being melted and pressed (pressed) at 25 MPa for 180 seconds. While being pressurized, the mold temperature was raised to 250 ° C. and held for 180 seconds, the mold temperature was cooled to 50 ° C., and then the pressure was released and demolded to obtain FRP.

  When the cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and the observation surface of the void is slightly seen near the outermost layer 96% of the resin was impregnated with resin. In this example, since the spun yarn was bonded with the covering yarn, it was FRP without going through the preform form. However, the melted yarn was made to follow the mold while melting the covering yarn. By forming the continuous fiber while passing through, a good FRP free from wrinkles was obtained with only a slight disturbance in fiber orientation. Further, since the flattening treatment was performed so that the yarn width / thickness ratio was 10, the surface smoothness was excellent.

(Example 3)
A molding material C was obtained with the same specifications as in Example 1 except that the stitch yarn A used was changed to the stitch yarn B.

  In the obtained molding material C, 75% of the reinforcing fiber yarns consisted of discontinuous fibers, and the handling property was retained by the twisting process, and the form as the spun yarn was retained, and was restrained by the stitch yarn. It was a level that could be handled sufficiently as a molding material.

  The obtained molding material C was placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape having a radius of curvature of 305 mm, and the preform was pressed. Obtained.

  The obtained preform was a good preform without the occurrence of wrinkles by releasing the in-plane distortion of the molding material by discontinuing discontinuous fibers constituting the spun yarn.

  Further, the obtained preform is placed again on the mold, and the nonwoven fabric A is allowed to follow the mold while being heated to 230 ° C., and is pressed (pressed) at 25 MPa for 240 seconds. After cooling the mold temperature to 50 ° C., the pressure was released and demolded to obtain FRP.

  The obtained FRP is excellent in resin impregnation property during molding because the stitch yarn remains, and the resin is impregnated even inside the reinforcing fiber yarn, and 99% of the observation surface is impregnated with the resin. It was. Further, since the fibers were restrained by the stitch yarn, the fiber orientation was not disturbed and no wrinkles were observed. Although the flattening process was performed so that the yarn width / thickness ratio was 10, the stitch yarn remained, and thus a slight unevenness was confirmed on the surface.

Example 4
Except that the nonwoven fabric A to be used was replaced with the nonwoven fabric B, a molding material D was obtained with the same specifications as in Example 1.

  In the obtained molding material D, 75% of the reinforcing fiber yarns are composed of discontinuous fibers, and the handling property was retained by the twisting process, and the shape as the spun yarn was retained, and was restrained by the stitch yarn. It was a level that could be handled sufficiently as a molding material.

  The obtained molding material D is placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape with a radius of curvature of 305 mm to press the preform. Obtained.

  The obtained preform was a good preform without the occurrence of wrinkles by releasing the in-plane distortion of the molding material by discontinuing discontinuous fibers constituting the spun yarn.

  Furthermore, the obtained preform is placed again on the mold, and while being heated to 150 ° C., the wrinkles generated while melting the nonwoven fabric B and the stitch yarn A are stretched to follow the mold and pressurized at 25 MPa for 180 seconds. (Pressing), the mold temperature was cooled to 50 ° C. while being pressurized, and then released and released from the mold to obtain FRP.

  In the obtained FRP, the resin was impregnated to the inside of the reinforcing fiber yarn, and although a void was slightly seen in the vicinity of the outermost layer, 96% of the observation surface was impregnated with the resin. In addition, scars of the stitch yarn were hardly left, but disorder of fiber orientation and wrinkles were hardly observed, and the surface quality was particularly excellent as compared with the FRPs of Examples 1 to 3.

(Example 5)
Among the procedures (1) to (6), a molding material I having 0 ° orientation was produced by the procedures (5) and (6). In addition, about said (5), the nonwoven fabric C is arrange | positioned, and it is the same method as -45 degree sheet | seat formation on it, and a reinforcing fiber thread is parallel to 0 degree with respect to a longitudinal direction, and 75 g / m. ² were formed to form a 0 ° sheet. After repeating this twice, through (6), a molding material I was produced in which two layers of 0 ° -oriented sheets were laminated and integrated. Further, in each of the 0 ° sheets constituting the laminate, spun yarn A was used for 75% of the reinforcing fiber yarns.

  In the obtained molding material I, 75% of the reinforcing fiber yarns consisted of discontinuous fibers, and the handling property was retained by the twisting process and retained as the spun yarn, and was restrained by the stitch yarn. It was a level that could be handled sufficiently as a molding material.

  The obtained molding material I was laminated in a configuration of [−45 ° / 90 ° / + 45 ° / 0 °] and placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter. To be pressed with a female die of the same shape having a curvature radius of 305 mm to obtain a preform.

The obtained preform was a good preform without the occurrence of wrinkles by releasing the in-plane distortion of the molding material by discontinuing discontinuous fibers constituting the spun yarn. Since the spun yarn is used in each orientation direction of the molding material, the formability is isotropically expressed and the molding material is individually laminated in each direction, so that shear deformation between layers is caused. It works effectively and has excellent shapeability.
Since 100% of the reinforcing fiber yarns were spun yarns, the shapeability was particularly excellent.

  Further, the obtained preform was placed again on the mold, and once heated to 150 ° C., the stitch yarn A was allowed to follow the mold while being melted, and pressed (pressed) at 25 MPa for 180 seconds. While being pressurized, the mold temperature was raised to 250 ° C. and held for 180 seconds, the mold temperature was cooled to 50 ° C., and then the pressure was released and demolded to obtain FRP.

  When the cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and the observation surface of the void is slightly seen near the outermost layer 96% of the resin was impregnated with resin. In addition, the occurrence of wrinkles was observed only when the fiber orientation was slightly disturbed, and since the flattening treatment was performed so that the yarn width / thickness ratio was 10, the surface smoothness was excellent. It was.

(Comparative Example 1)
The molding material (blank) obtained by the procedures (1) to (6) was used as the molding material E. In the molding material E, 100% of the reinforcing fiber yarns remained in a continuous state.

  The obtained molding material E was all of the reinforcing fiber yarns constituting it or was a continuous fiber, and was held by stitch yarns, so it was excellent in handling properties as a molding material.

  A preform and FRP were produced in the same manner as in Example 1 using the obtained molding material E.

  Since the obtained preform has all the reinforcing fiber yarns continuously, the reinforcing fiber yarns are stretched at the time of shaping and cannot be made to follow a hemisphere. As a result, sputum occurred frequently.

  Furthermore, when a cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and a void is slightly seen in the vicinity of the outermost layer. 96% of the observation surface was impregnated with resin. In addition, since the stitch yarn A and the nonwoven fabric A are melted, the degree of freedom of deformation is generated, so the wrinkles in the preform are somewhat relieved, but the surface irregularities and fiber orientation disturbance remain in the FRP, and the quality is improved. It was quite inferior.

(Comparative Example 2)
Among the molding materials (blanks) produced by the procedures (1) to (6), the spun yarn A is used for 50% of the reinforcing fiber yarns constituting the −45 ° sheet, the 90 ° sheet, and the + 45 ° sheet. Thus, molding material F was obtained. Such spun yarn A (fineness: 800 tex) is obtained by twisting a discontinuous fiber obtained by cutting a reinforcing fiber yarn into a fiber length La = 50 mm into a yarn by twisting at a twist number = 100 turns / m. The flattening process was performed so that the thread width / thread thickness = 10.

  In the obtained molding material F, 37.5% of the reinforcing fiber yarns are composed of discontinuous fibers, and the handling property is a level that can be stably handled as a molding material because many continuous fibers remain. It was.

  The obtained molding material E is placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape with a radius of curvature of 305 mm to press the preform. Obtained.

  In the obtained preform, although discontinuous fibers constituting the spun yarn were partially removed, a large amount of continuous fibers remained, so that all the distortion in the surface of the molding material could not be alleviated, and Comparative Example 1 Although it was better than that, there were frequent wrinkles.

  Further, the obtained preform was placed again on the mold, and once heated to 150 ° C., the stitch yarn A was allowed to follow the mold while being melted, and pressed (pressed) at 25 MPa for 180 seconds. While being pressurized, the mold temperature was raised to 250 ° C. and held for 180 seconds, the mold temperature was cooled to 50 ° C., and then the pressure was released and demolded to obtain FRP.

  Furthermore, when a cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and a void is slightly seen in the vicinity of the outermost layer. 96% of the observation surface was impregnated with resin. In addition, since the stitch yarn A and the nonwoven fabric A are melted, a degree of freedom of deformation is generated, so that the wrinkles in the preform are somewhat relieved, but the surface irregularities and fiber orientation disturbance remain in the FRP and are inferior in quality. It was a thing.

(Comparative Example 3)
Of the molding material (blank) produced by the procedures (1) to (6), the spun yarn C is used for 75% of the reinforcing fiber yarns constituting the −45 ° sheet, the 90 ° sheet, and the + 45 ° sheet. Thus, a molding material G was obtained. The spun yarn C (fineness: 800 tex) is obtained by twisting a discontinuous fiber obtained by cutting a reinforcing fiber yarn into a fiber length La = 300 mm into a yarn by twisting at a twist number = 100 turns / m. The flattening process was performed so that the thread width / thread thickness = 10.

  In the obtained molding material G, 75% of the reinforcing fiber yarns are composed of discontinuous fibers, and the handleability is stable because the length of the discontinuous fibers is long, and the spun yarn form is stably maintained. Excellent handling as a molding material.

  The obtained molding material G is placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape with a radius of curvature of 305 mm, and a preform is pressed. Obtained.

  Since the obtained preform has a long discontinuous fiber length, the resistance when the spun yarn passes through increases, and the reinforcing fiber yarns stretch in part and cannot follow the mold well. Habit occurred.

  Further, the obtained preform was placed again on the mold, and once heated to 150 ° C., the stitch yarn A was allowed to follow the mold while being melted, and pressed (pressed) at 25 MPa for 180 seconds. While being pressurized, the mold temperature was raised to 250 ° C. and held for 180 seconds, the mold temperature was cooled to 50 ° C., and then the pressure was released and demolded to obtain FRP.

  Furthermore, when a cross section cut out from the obtained FRP so as to have a width of 2 cm is observed with an optical microscope, the resin is impregnated into the inside of the reinforcing fiber yarn, and a void is slightly seen in the vicinity of the outermost layer. 96% of the observation surface was impregnated with resin. In addition, since the stitch yarn A and the nonwoven fabric A are melted, a degree of freedom of deformation is generated, so that the wrinkles in the preform are somewhat relieved, but the surface irregularities and fiber orientation disturbance remain in the FRP and are inferior in quality. It was a thing.

(Comparative Example 4)
Of the molding material (blank) produced by the procedures (1) to (6), the spun yarn D is used for 75% of the reinforcing fiber yarns constituting the −45 ° sheet, the 90 ° sheet, and the + 45 ° sheet. Thus, molding material H was obtained. The spun yarn D (fineness: 800 tex) is obtained by twisting a discontinuous fiber obtained by cutting a reinforcing fiber yarn into a fiber length La = 5 mm into a yarn by twisting at a twist number = 100 turns / m. The flattening process was performed so that the thread width / thread thickness = 10.

  In the obtained molding material H, 75% of the reinforcing fiber yarns are composed of discontinuous fibers, and the handleability is short because the fiber length of the discontinuous fibers is short. Even in the form of the material, the fibers dropped out.

  The obtained molding material H was placed on a hemispherical female mold having a radius of curvature of 300 mm at the maximum diameter, and pressed from above with a female mold of the same shape with a radius of curvature of 305 mm to press the preform. Obtained.

  Since the obtained preform had a short fiber length of discontinuous fibers, it was deformed even when placed on the mold, but once it was shaped beautifully, it was out of shape when taken out from the mold, The form as a preform could not be maintained.

  Table 1 shows the results of the above examples and comparative examples.

  As shown in Tables 1 and 2, among the reinforcing fiber yarns constituting the laminate in which the reinforcing fiber yarns are n-axis oriented, (100-100 / n)% or more, that is, in this example. About 75% or more, the fiber length La is composed of spun yarns made of discontinuous fibers having a finite length of 10 to 100 mm. It was confirmed that an excellent effect was exhibited. Among them, the embodiment of Example 2 is a preferable embodiment because it is excellent in both the handling and shaping properties of the molding material.

  Further, in the molding of FRP, excellent characteristics are shown in each of Examples 1, 3, and 4, and when pursuing the excellent mechanical properties of FRP, pursuing the excellent design characteristics of Example 3 and FRP In Example 4, and in consideration of these balances, it was Example 1.

  For example, in a structural member that requires mechanical characteristics in an automobile member, it may be Example 2 to Example 3, or a combination thereof. Examples 2 to 4 or a combination thereof. That is, it can be said that the combination of Example 2 and Examples 3 to 4 is an ideal aspect of the present invention.

  According to the molding material of the present invention, the handling property is excellent, and in the molding of FRP having a complicated shape, it is possible to suppress wrinkles and disorder of the orientation of the reinforcing fiber yarn. Therefore, a high-quality FRP can be obtained with high productivity. Such a molding material can be suitably used for a structural member of a transportation device such as an automobile, an aircraft, and a ship, a building member, and the like.

It is a schematic perspective view which shows one embodiment of the molding material of this invention. It is a schematic sectional drawing of the preform which shape | molded the molding material of this invention in the arch shape. It is a schematic sectional drawing which shows one embodiment of the molding material before the textile body (nonwoven fabric) in this invention fuse | melts. It is a schematic sectional drawing which shows one embodiment of the molding material of the state by which the textile body (nonwoven fabric) in this invention was fuse | melted.

Explanation of symbols

1, 8, 11: Molding material 2, 10: Reinforcing fiber yarn (spun yarn)
3, 12: Textile body (nonwoven fabric)
4, 13: Stitch yarn 5: Reinforcing fiber yarn direction (0 ° direction)
6: Direction in which the stitch yarn extends 7: Longitudinal direction of the molding material 9: Sheet constituting the molding material

Claims (12)

A plurality of layers of sheets in which a large number of reinforcing fiber yarns are arranged in parallel are laminated to form a laminate, and a multilayer molding material in which the laminate is integrated. C. A molding material characterized by satisfying the requirements of (c).
(A) A textile body comprising as a component a first thermoplastic resin constituting a matrix of a composite material is disposed at least between the sheets,
(B) The laminated body is integrated by a stitch yarn having the second thermoplastic resin as a component and / or a textile body having the first thermoplastic resin as a component,
(C) including a sheet which is a spun yarn composed of discontinuous fibers having a finite length of 10 to 100 mm, and the fiber length La of the reinforcing fiber yarn constituting the laminated body,
(D) Spinning in which at least 50% or more of the reinforcing fiber yarns constituting the laminate are composed of discontinuous fibers having a finite length in which the fiber length La of the reinforcing fiber yarns constituting the laminate is 10 to 100 mm. It is a thread. Each of the sheets constituting the laminate is laminated in a multiaxial orientation so that the reinforcing fiber yarns intersect to constitute a laminate, the number of axes to be oriented is n-axis, and the fiber length La is 10 The molding material according to claim 1, wherein n and N satisfy the relationship of the following formula, where N% is a ratio of spun yarn composed of discontinuous fibers having a finite length of -100 mm.
(100-100 / n) ≦ N The molding material according to claim 1 or 2, wherein the fineness of the spun yarn is 300 to 5,000 tex, and the yarn width W / yarn thickness T is 2 to 20. The molding material according to any one of claims 1 to 3, wherein the number of twists of the spun yarn is in the range of 200 to 5 turns / m. The molding material according to any one of claims 1 to 3, wherein the spun yarn is substantially untwisted and is covered and collected by an auxiliary fiber yarn. The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy a relationship of (Tm1-150) ≦ Tm2 ≦ (Tm1-20). The molding material as described. The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy a relationship of (Tm2-150) ≦ Tm1 ≦ (Tm2-20). The molding material as described in 2. The melting point Tm1 of the first thermoplastic resin and the melting point Tm2 of the second thermoplastic resin satisfy a relationship of (Tm2-20) <Tm1 <(Tm2 + 20). Molding material. In the sheet, in the range basis weight of the reinforcing fibers is 50 to 350 g / ^{m 2,} the molding material according to claim 1 having a basis weight of the帛体is in the range of 15~250g / ^{m 2} . A preform characterized in that one or more of the molding materials according to any one of claims 1 to 9 are laminated and formed into a single contour shape or a double contour shape. The length Lc and the fiber length La of the arc in each cross section in the reinforcing fiber yarn direction of each sheet constituting the molding material in a portion formed into a single contour shape or a double contour shape are Lc> La. The preform according to 10. A fiber-reinforced resin formed using the molding material or preform according to any one of claims 1 to 11.

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