JPH0455085B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention is applicable to the inner surface of the door, inner surface of the ceiling,
The present invention relates to a method for manufacturing reinforcing materials for thin plate structural members such as iron plates and aluminum plates for the inner surface of bonnets, the inner surface of trunk rooms, and aircraft and other equipment. [Prior art and its problems] The use of a prepreg sheet made of ultraviolet curable resin as a vibration damping reinforcing material for thin plate structural members was proposed in JP-A-56-153137, JP-A-59-1250, etc. However, simply adhering prepreg sheets is insufficient for reinforcement. Therefore, it is possible to provide ribs for reinforcing the prepreg sheet, but conventionally the prepreg is formed by wrinkles, but the shape of the wrinkles becomes irregular, which is not preferable. It has also been proposed to insert a filler to form ribs when adhering the prepreg, but this requires a specially shaped filler, making it expensive, making the structural member heavier by the weight of the filler, and making the process more complicated. The workability is poor. [Means for Solving the Problems] The present invention solves the above problems and eliminates the above drawbacks by forming recessed ribs on the prepreg sheet. That is, in the present invention, ribs are formed on a piece of prepreg sheet using a matrix, and only the rib portions are irradiated with ultraviolet rays to cure only the rib portions. Although a masking suppressing type is used to cure only the rib portions, other masks, screens for blocking ultraviolet rays, etc. may be used instead. [Function] In the present invention, the prepreg sheet is formed with recessed ribs, so when it is incorporated into an automobile manufacturing line, the prepreg sheet can be sent as is to the required thin plate structural member and cured with ultraviolet rays. In the present invention, the prepreg sheet does not necessarily have to be impregnated, but also includes sheet compounds containing chopped strands.
This chopped strand-containing sheet compound is made of, for example, 2 coated with an ultraviolet curable resin composition.
A sheet made by interposing chopped strands between two sheets of resin film (in this case, the chopped strands may be made into a mat shape), or chopped strands and ultraviolet curing type Any material such as a sheet formed by kneading a resin composition and extruding it onto a resin film may be used. In addition, the above-mentioned ultraviolet curable resin composition includes a compound having a photopolymerizable group in addition to the epoxy resin, such as an acryloyl group, a methacryloyl group, an acrylamide group, a maleic acid diester group, an allyl group, a vinyl ether group, a vinyl amino group, Examples include compounds having a glycidyl group, an acetylenically unsaturated group, and the like. [Example] The above-mentioned ultraviolet curable epoxy resin composition 1 as shown in the first diagram includes an epoxy resin 2, an epoxy resin 3,
Organic silicon compound 4 was mixed at 100°C, photocuring catalyst 5 was added thereto, and the mixture was mixed at 100°C. The materials and mixing ratio of the resins 2 and 3, compound 4, and catalyst 5 are as follows.・Resin 2: 12 parts by weight of Epicoat 828 (Yuka Ciel Epoxy Co., Ltd.) Bisphenol A
type epoxy resin) - Resin 3: Epicoat 1001 48 parts by weight ( General Electric Co., Ltd. (50% solution of triarylsulfonium salt in propylene carbonate) In order to make the prepreg sheet 6 from the ultraviolet curable epoxy resin composition 1, it was heated in an impregnating bath in a room free from ultraviolet rays as shown in the second figure. 10, and this impregnation tank 10 is heated by a heating device 11 to approx.
A base fabric 12 made of a material that transmits ultraviolet rays, such as pine, glass, or cloth, is fed into an impregnating tank 10 while being heated to 100°C, and then a release paper 13 is applied to the back side of the impregnated base fabric 12 as it is fed. It is made into a product by winding it into a coil. Examples of the material for the base fabric 12 include the following. Glass fibers (there are various processing forms; for example, surf-es mat as a single fiber mat, strand as a long fiber mat), organic fibers (synthetic fibers such as linear polyester, nonwoven fabrics of synthetic fibers), etc. are used. Next, in order to manufacture a vibration damping reinforcing material for a thin plate structural member, the prepreg sheet 6 shown in FIG. 3A is cut into a certain size by punching as shown in FIG. As shown in Figure 3, warm air 20
The ribs 6b as shown in FIG.
is formed using a hot press. The shape of the rib 6b may be any shape such as an x shape, a cross shape, a river shape, a mouth shape, etc. as shown in FIGS. Next, the piece 6a is attached to the rib 6b of the piece 6a as shown in FIG.
The other parts are covered with masking molds 23, 23, etc. so as not to be exposed to ultraviolet rays, and the ultraviolet rays 24 are irradiated from above only to the rib 6b part to harden only the rib 6b part, as shown in FIG. Then, they are removed from the matrix 22 and the masking press molds 23, 23, . . . and stacked with release papers 25, 25, . Next, in order to use the damping reinforcement material 6c, as shown in FIG.
A primer 28 made of an ultraviolet curable resin composition is placed on the surface to which the reinforcing material 6c is to be bonded.
Apply. Note that this primer 28 may be applied by screening, tracing, or the like. Further, if the damping reinforcing material 6c itself has adhesive properties, this primer 28 is not necessary. In addition, vibration damping reinforcement material 6c
The material itself may be preheated with hot air or the like to make it sticky. Thus, if the vibration damping reinforcing material 6c is placed on the thin iron plate 26 as shown in FIG. Hardens in a short time,
It is fixed integrally with the thin iron plate 26. Figure 4 shows an application example of the thin steel plate reinforced in this way.A shows the case where the present invention is applied to an automobile door, and B shows the case where the invention is applied to the same ceiling, both of which are used for vibration damping reinforcement on an automobile assembly line. The vibration damping reinforcing material 6c can be applied by placing the material 6c vertically or horizontally in contact with the thin iron plate 26 and irradiating it with ultraviolet light 29. Example Ultraviolet curable epoxy resin composition 1 Resin 2: 12 parts by weight of Epicote 828 (Yuka Ciel Epoxy Co., Ltd. Bisphenol A
type epoxy resin) ・Resin 3: Epicoat 100148 parts by weight (〃 〃) ・Compound 4: 2 parts by weight of KBM 202 (Shin-Etsu Chemical Co., Ltd., diphenyldimethoxysilane) ・Photocuring catalyst 5: 0.6 parts by weight of UVE-1014 (General Electric Co., Ltd. 50% propylene carbonate solution of triarylsulfonium salt) Base fabric 12 MC 450A (Chopped strand mats Nitto Boseki) Steel plate - Cold rolled steel plate specified in JIS G 3141
(150 x 50 x 0.3 mm) Prepreg thickness 1.0 mm Curing method: 40 mW/cm ² x 30 seconds, TB 3111 (ultraviolet curing epoxy, Three Bond Co., Ltd.) as a primer - Reinforcement method 1 Reinforcement with flat prepreg (No. Comparative example in Figure 5 A) 2 Reinforcement with one rib prepreg (Figure 5 B) (R = 3 mm) 3 Reinforcement with cross rib prepreg (Figure 5 C) (R = 3 mm) The above three methods are in accordance with JIS K 6911. Perform a bending test using the same method to determine the flexural modulus (Ef),
From this value, the bending stiffness (Gf) was determined and the degree of reinforcement was determined. Note that Ef and Gf at this time were calculated using the following formulas. Ef=LV ³ /4Wh ³・F/Y Gf=Ef・Wh ³ /12 * Here Ef: Flexural modulus (Kg/mm ² ) Lv: Distance between fulcrums (mm) W: Width of test piece (mm) h: 〃 Height (mm) F/Y: Slope/result of the straight line part of the load-deflection curve

〔effect〕

In the present invention, since the pre-preg sheet is formed with recessed ribs, the prepreg sheet can be sent as is when it is assembled into an automobile manufacturing line, which improves workability and eliminates the need for padding, which also reduces the weight of the structural member. It is something that never happens. Furthermore, when the above-mentioned ultraviolet curable resin composition is used, if the prepreg sheet is irradiated with ultraviolet rays, the prepreg sheet will harden in a short time and adhere to the thin plate structural member, resulting in good workability and low equipment costs, making it suitable for mass production. It is something. Furthermore, by making the prepreg sheet flexible, it can be easily and reliably adhered to a thin plate structural member of any shape.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the method for producing the ultraviolet curable resin composition in the present invention, Fig. 2 is an explanatory diagram of the method for producing the prepreg sheet, and Fig. 3 is a, b, c,
D, H, H, and G are explanatory diagrams of embodiments of the method of the present invention,
FIGS. 4A and 4B are explanatory views of applied examples of the present invention, FIG. 5A is a comparative example, and FIGS. 5B, C, D, H, and F are perspective views of embodiments of the present invention. 1... Ultraviolet curable resin composition, 6... Prepreg sheet, 6a... Piece of prepreg sheet, 6
b... Rib, 6c... Vibration damping reinforcing material for thin plate structural members, 22... Matrix, 24, 29... Ultraviolet rays.

Claims (1)

[Claims] 1. An uncured prepreg sheet is formed from an ultraviolet curable resin composition, and ribs are formed on a piece of this prepreg sheet using a matrix, and only the rib portions are irradiated with ultraviolet rays, and only the rib portions are cured. A method for producing a reinforcing material for a thin plate structural member, which is obtained by curing the material. 2. The method for producing a reinforcing material for a thin plate structural member according to claim 1, wherein the ultraviolet curable resin composition is an epoxy resin.