JP2006152099A - Prepreg - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a prepreg having excellent mechanical characteristics, surely recognizable on forming and also becoming a forming material of an inexpensive composite material. <P>SOLUTION: This prepreg consisting of a reinforcing fiber and a matrix resin is characterized in that a marking is performed on the surface of the prepreg by using a dyestuff and/or pigment having ≥30 ΔE color difference in the colors of the marking with the surface of the prepreg, and the content of the dyestuff and/or pigment is ≤100 mg per 1 m<SP>2</SP>prepreg. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a prepreg suitable for a molding material for a composite material that is required to be lightweight.

  Composite material parts applied to golf shafts, aircraft parts, etc. are manufactured by arranging and laminating fabric-like, tape-like or tow-like prepregs on a forming jig in any fiber direction, and heating and curing. Yes. In this case, prepregs having different strengths, elastic moduli or basis weights of the reinforcing fibers, and further different weight ratios of the matrix resin may be used in combination. In addition, in order to meet specific objectives for expressing specific composite characteristics and requirements for handling properties, prepreg systems having different resin compositions and resin amounts may be used on the front and back sides of the prepreg.

However, when these prepregs are laminated, there is a possibility that materials and prepregs may be mixed up and down, and as a result, there is a problem that the laminated workability is affected and a composite material part having the desired strength cannot be obtained. It was.
Conventionally, a method for changing the color of a release paper or a plastic film serving as a prepreg carrier or displaying a product name has been proposed for these problems (see Patent Document 1). In addition, a method for forming a concavo-convex pattern using the release paper or plastic film has been proposed. However, since these are peeled off during the laminating operation, the identification function cannot be exhibited after being peeled off, and there is still a high possibility that the materials and the prepreg will be mistaken.
Also, as is well known, many adhesive films are themselves colored. In this way, it is possible to change the color tone of the entire prepreg to the original color tone by coloring the entire matrix resin, but there is a demand for efficient production of a small variety of products. In this business environment, production efficiency will be significantly impaired. In other words, when producing colored and non-colored varieties in a limited production line, it is necessary to clean the production machine in each process of the fiber reinforced prepreg with a large number of processes. It becomes.

On the other hand, a method of inserting a tracer yarn into a reinforcing fiber as a base material or a fabric using the same is known (see Patent Document 2, Patent Document 3 and Patent Document 4). Here, a method is shown in which inorganic fibers or organic fibers such as aramid fibers, glass fibers, and metal fibers are used as tracer yarns for carbon fibers that are reinforcing fibers. In addition, when these tracer yarns are used, a method of incorporating the tracer yarn in a fabric base material that uses the tracer yarn in advance, a method of supplying the tracer yarn simultaneously when manufacturing the prepreg, and manufacturing a prepreg are proposed.
Although these methods make it possible to identify the type and the front and back of the prepreg, the strength of the composite material may be impaired. For example, in the case of metal fibers, there is a problem that the strength of the composite material is reduced due to the occurrence of metal corrosion due to moisture absorption of the matrix resin. In addition, in the case of aramid fibers, there is a problem in that the strength of the composite material is reduced due to moisture absorption by itself, and when the molded body is manufactured by stacking the prepregs on which the tracer yarns are arranged, the positions of the tracer yarns in each layer may overlap. In many cases, the problem that the strength of the composite material of the part is lower than that of the other part is unavoidable. In addition, depending on the material used as a tracer, there is a problem that the cost increases.
Japanese Utility Model Publication No. 62-80616 Japanese Patent Laid-Open No. 9-85892 JP-A-10-195213 JP 2000-110046 A

  Accordingly, an object of the present invention is to provide a prepreg which is an inexpensive composite material for molding, which has excellent mechanical properties, can be surely identified during molding.

  In order to achieve the above object, the prepreg of the present invention is a prepreg composed of reinforcing fibers and a matrix resin, wherein the surface of the prepreg is marked.

According to a preferred embodiment of the present invention, the hue color difference ΔE between the marking and the prepreg surface is 30 or more, the marking is composed of a dye and / or a pigment, and the marking is per 1 m ² of the prepreg. The content is 100 mg or less.

  ADVANTAGE OF THE INVENTION According to this invention, the prepreg which is the raw material for composite materials which was excellent in the distinguishability while maintaining the outstanding mechanical characteristic can be obtained. As a result, it is possible to prevent the misalignment of the stacking order when using a combination of multiple types of prepreg, such as the direction and front and back of the prepreg for cutting that have been cut into a predetermined shape in advance, and a composite with the desired strength. Material parts can be obtained at low cost.

The prepreg of the present invention needs to be marked on the prepreg surface so that it can be easily identified. If the marking has a hue difference ΔE of 30 or more with the prepreg itself, it is easy to laminate the prepreg according to the shape of the target product (composite material part) without impairing workability from the color difference. The hue color difference ΔE is preferably 40 or more, more preferably 50 or more. If the hue color difference ΔE is less than 30, sufficient discrimination may not be obtained.

  The marking used in the prepreg of the present invention is not particularly limited as long as it has a hue color difference ΔE of 30 or more from the prepreg as described above, but is preferably a dye and / or a pigment from the viewpoint of convenience. The type of the dye and / or pigment is not particularly limited, and a known and commercially available one can be used. Commonly used pigments and dyes include titanium oxide and zinc oxide pigments for white, Bengala (iron oxide) pigments for red, and carbon black, iron oxide pigments and aniline black dyes for black. Etc.

  Further, as a marking method, a method using a stamp, an ink jet printer, an air brush, a spray, or the like can be selected as necessary. Among these, it is preferable to use an inkjet printer in terms of versatility, handleability, and ink consumption.

  The method for producing the prepreg of the present invention is not particularly limited, but may include a hot melt method in which a matrix resin is once formed into a film, or directly heated and melted and impregnated into a reinforcing fiber base, or a solvent method in which the resin is dissolved and impregnated in a solvent. It is possible to select a known method.

  Here, the method for producing the marked prepreg may be to produce a prepreg using a substrate that has been marked on the surface in advance, or after marking on the surface of the substrate, the resin is continuously impregnated and processed into a prepreg. May be manufactured. Alternatively, the outermost surface of the prepreg may be marked after the resin impregnation step. In addition, the obtained prepreg can be slit into an arbitrary width as required to obtain a product.

  The surface to be marked may be only one surface or both surfaces of the substrate or the prepreg, and can be selected according to requirements and purposes.

  The interval and arrangement of the markings can be arranged at an arbitrary interval or an arbitrary size with respect to the longitudinal direction or machine width direction during prepreg processing.

Further, the content of the dye and / or pigment (marking) to be used is preferably 100 mg / m ² or less, more preferably 80 mg / m ² per 1 m ² of the prepreg. When content exceeds 100 mg / m < ² >, intensity | strength etc. may fall.

  The marking may be character information such as product name, lot number, “Omote” and “Ura”, or any symbol, or information such as a barcode or any shape pattern depending on the purpose and purpose of identification. It may be.

1 and 2 are explanatory views illustrating the arrangement of markings in the embodiment of the present invention.
In FIG. 1 and FIG. 2, the code prepreg 1 is held on a release paper 2 and marked for identification by a marking 3. In FIG. 1, the example which printed the name of the used reinforcing fiber base material on the surface was shown in FIG. 2, and the example which performed the marking for identification using an airbrush was shown.

  Examples of the reinforcing fibers that serve as the base material of the prepreg of the present invention include carbon fibers and glass fibers, but organic fibers such as nylon fibers and aramid fibers, ceramic fibers such as boron fibers and silicon carbide fibers, etc. Can also be used, and these can be used in combination. These reinforcing fibers can be prepreg in a state in which they are aligned in one direction, and may be preliminarily woven, or may be in the form of a nonwoven fabric or mat, and the form is not limited.

  Examples of the matrix resin used in the present invention include, in addition to epoxy resins, unsaturated polyester resins, vinyl ester resins, phenol resins, bismaleimide resins, cyanate ester resins, polyphenylene sulfide resins, polyether sulfone resins, poly Examples include ether imide resins, polyether ether ketone resins, polyamide resins, polyimide resins, polycarbonate resins, and polypropylene resins. Regarding these matrix resins, resins suitable for the purpose can be selected as appropriate, but epoxy resins are particularly preferably used from the viewpoint of the mechanical properties of the resulting composite material and the handleability of the prepreg.

In addition, the reinforcing fiber basis weight (FAW) and the matrix resin content (Wr) of the prepreg in the present invention are not particularly limited and can be set according to the use and purpose of the prepreg product. Is preferably 10 to 1000 g / m ² , more preferably 30 to 700 g / m ² . In addition, Wr is preferably 10 to 60 wt%, more preferably 25 to 50 wt%, from the viewpoint of the handleability of the prepreg product and the mechanical properties of the composite molded body that is the final product.

  The prepreg of the present invention is suitably used for aircraft and automobile members, sports equipment such as golf shafts and tennis rackets.

  Hereinafter, the present invention will be specifically described based on examples. The measuring method of each characteristic in the present invention is as follows.

<Color difference ΔE>
Using a color computer SM-T manufactured by Suga Test Instruments Co., Ltd., using a light source conforming to JIS Z 8722 (2000), under the following conditions, the lightness index defined in JIS Z 8729 (1994): L, The a and b values, which are indicators of hue and saturation, were measured. Further, the color difference ΔE was determined according to the following equation from the L, a, b measurement values of the prepreg surface and the L ′, a ′, b ′ measurement values of the respective colors.

ΔE = {(L−L ′) ^ 2+ (aa ′) ^ 2+ (b−b) ^ 2} ^ 0.5
Light source Halogen lamp Optical conditions Reflection measurement: 8 degree illumination, diffused light reception 8 / d, measurement hole diameter 30 mm diameter
・ Receiver C light 2 degree field of view <interlaminar shear strength>
The prepreg was laminated and cured under predetermined conditions, and measured according to ASTM D2344.

<Ink content>
Marking was performed during prepreg manufacture, and the ink consumption per unit prepreg area was obtained by dividing the ink consumption weight by the area of the prepared prepreg.

<Distinguishability during laminating work>
The pattern was cut into a trapezoidal shape as shown in FIG. 3, and the workability when laminated 100 times using a prepreg to which a release paper and / or a cover film was not attached was relatively evaluated and classified as follows.
○: All can be laminated smoothly without losing both sides.
(Triangle | delta): The thing which hesitated front and back and mistakenly laminated were less than 10 times.
X: The thing which lost the front and back, and misstacked 10 times or more.

[Example 1]
Carbon fiber “Torayca” (registered trademark) T700S-12K (manufactured by Toray Industries, Inc., tensile strength 4900 MPa, tensile elastic modulus 233 GPa) is aligned in one direction so that the carbon fiber basis weight is 150 g / m ^2. It is sandwiched from above and below with a resin film having a basis weight of 32 g / m ² prepared in advance using epoxy preparation resin # 2500 manufactured by Toray Industries, Inc., and impregnated by a hot melt method at a processing temperature of 120 ° C. and a processing speed of 7 m / min. A prepreg having a resin content of 30 wt% and a machine width direction of about 1010 mm was continuously produced.

The marking is a carbon fiber species name used as shown in Table 1 on the surface of the prepreg subjected to the impregnation process, using an industrial inkjet printer 43S manufactured by Videojet Japan Co., Ltd. and white ink 16-2960 manufactured by the company. "T700S" was printed on one side of the prepreg with the arrangement and frequency shown in FIG. As shown in Table 1, the color difference ΔE between the ink used and the prepreg without printing was 65, and the amount of ink used was 32 mg per prepreg m ² . As a result of quality evaluation, it was confirmed that the prepreg had good interlaminar shear strength and good discriminability in the laminating operation.

[Comparative Example 1]
A prepreg was prepared in the same manner as in Example 1 except that no marking was performed. Although a good value was obtained for the interlaminar shear strength, there were many cases where the front and back sides were not known at the time of laminating work, and there was a problem in laminating workability, such as the need to correct erroneous lamination. The results are shown in Table 1.

[Example 2]
Carbon fiber “Torayca” (registered trademark) M30S-18K (manufactured by Toray Industries, Inc., tensile strength 5690 MPa, tensile elastic modulus 294 GPa) is aligned in one direction so that the carbon fiber basis weight is 150 g / m ^2. An epoxy preparation resin # 2500 manufactured by Toray Industries, Inc. was impregnated by a hot melt method to continuously produce a prepreg of about 1010 mm in the machine width direction. The marking was performed in the same manner as in Example 1, but “M30S” was printed according to the carbon fiber type name used. As shown in Table 1, the amount of the ink used was 30 mg per 1 m ² of the prepreg, and it was confirmed that the prepreg had good interlayer shear strength and good discrimination in the laminating operation.

[Example 3]
A prepreg was produced in the same manner as in Example 2 except that the ink used was red ink 16-2800 manufactured by VideoJet Japan Co., Ltd. As shown in Table 1, the color difference ΔE between the used ink and the prepreg without printing was 61, and the amount of the used ink was 30 mg per 1 m ² of the prepreg. As a result of quality confirmation, it was confirmed that the prepreg had good interlaminar shear strength and good discrimination in lamination work. The results are shown in Table 1.

[Example 4]
A prepreg was prepared in the same manner as in Example 2 except that the ink used was Green Ink 16-2950 manufactured by Videojet Japan. As shown in Table 1, the color difference ΔE between the used ink and the prepreg without printing was 36, and the amount of the used ink was 30 mg per 1 m ² of the prepreg. As a result of quality confirmation, satisfactory values of satisfactory interlaminar shear strength were obtained. However, although discriminability in the laminating operation was slightly inferior to that of the other examples, there was substantially no problem. The result was sufficient. The results are shown in Table 1.

[Example 5]
Carbon fiber "Torayca" (registered trademark) T300B-3K (Toray Industries Co., Ltd., tensile strength 3800MPa, tensile modulus 233GPa) carbon fiber basis weight using a plain weave cloth raw of 190 g / ^{m 2} width of about 1010mm with, This was impregnated with epoxy preparation resin # 2500 manufactured by Toray Industries, Inc. by a hot melt method to continuously produce prepregs. Marking was performed in the same manner as in Example 1. As shown in Table 1, the color difference ΔE between the ink and the prepreg was 65 as in Example 1, and the amount of ink used was 32 mg per 1 m ² of the prepreg. As a result of quality evaluation, it was confirmed that the prepreg had good interlaminar shear strength and good discriminability in the laminating operation. The results are shown in Table 1.

[Example 6]
Although the prepreg was produced by the same method as Example 5, marking was performed with the arrangement and size as shown in FIG. 2 using an airbrush. As shown in Table 1, the color difference ΔE between the ink and the prepreg was 65 as in Example 1, and the prepreg had good discrimination in the laminating operation. The amount of the ink used was 96 mg per 1 m ² of the prepreg, and a slight decrease in the interlaminar shear strength was observed, but it was in a range where there was no actual harm. The results are shown in Table 1.

FIG. 1 is a plan view for illustrating the arrangement of markings. FIG. 2 is a plan view for illustrating the arrangement of other markings. FIG. 3 is a perspective view illustrating a trapezoidal pattern cut in order to evaluate the distinctiveness during the stacking operation.

Explanation of symbols

1: Prepreg
2: Release paper
3: Marking

Claims (4)

  A prepreg comprising a reinforced fiber and a matrix resin, wherein the prepreg surface is marked.   The prepreg according to claim 1, wherein a hue color difference ΔE between the marking and the prepreg surface is 30 or more.   The prepreg according to claim 1 or 2, wherein the marking comprises a dye and / or a pigment. The prepreg according to claim 1, wherein the marking has a content of 100 mg or less per 1 m ² of the prepreg.

Images