JPS59386B2 - Manufacturing method for deep drawing molded products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a deep-drawn product made of hard fiberboard.

Conventionally, fiberboards have been molded by heating and pressurizing, but this is limited to molding with slight deformation, and deep drawing molding is not possible.

There is also a method of heating and press-molding a fiber mat that is made into a fiberboard by heat-pressing, but when producing a drawn-molded product with flanges from a single mat, the base and tip of the molded product are Due to the relationship between the pressure applied and the fluidity of the fibers, there is a limit to the drawing process, which may cause cracks, wrinkles, etc. during molding.
It has been difficult to obtain satisfactory deep-drawn products.

As described above, the present invention uses a hard fiberboard and a fiber mat together, which are difficult to deep draw when used alone.The hard fiberboard is provided with a notch at the part where it is to be molded, and the interior of the notch is The peripheral surface is formed into an uneven surface, the peripheral edge of the notch is softened with water, a fiber mat containing a thermosetting resin is polymerized, and the mat is heat-press molded together with a hard fiberboard to form a flat plate. The flange part and the base of the molded part are made of hard fiberboard, the drawn part is made of matte, and the two are joined and integrated to form a deep drawn product.Deep drawing is extremely simple and easy. The purpose is to efficiently produce deep drawing molded products with fewer defective products.

To explain the method of the present invention in detail, a hard fiberboard manufactured by a conventional method is cut into predetermined shapes and dimensions, and a notch is provided in the center of the area to be deep drawn. Form the surface into an uneven surface.

This step is preferably performed by a punching method.

Note that it is preferable that the shape of the notch is similar to the shape of the aperture.

Next, add 40% moisture to the periphery of the notch in this hard fiberboard.
% or less to make the peripheral edge of the notch sufficiently soft.

The width of the periphery of the notch to absorb water is 1/3 to 1 of the drawing depth.
/2 is optimal.

Next, the shape of fibers containing a thermosetting resin that is made into a fiberboard with approximately the same thickness as the hard fiberboard by the press molding process in the next step is squeezed into the molded part of the hard fiberboard that has been softened by moisture.
A mat having the shape and size required for the depth is placed over the notch of the hard fiberboard and polymerized.

This mat is, for example, a mat mainly composed of wood pulp fibers consisting of 70% wood pulp fibers, 10% fibers with higher tensile strength than wood pulp fibers, and 20% thermosetting resin, or A mat mainly composed of fibers with high tensile strength and thermosetting resin, or single fibers with high tensile strength rather than wood pulp fibers made of these and wood pulp fibers is used.

The blending ratio of each fiber and thermosetting resin is appropriately selected depending on the shape, depth, etc. of the aperture.

Thermosetting resin requires a minimum of 2%.

Next, the hard fiberboard on which the above mat was placed was inserted between the female mold and the male mold of the press, and the temperature was 130 to 150°C and the pressure was 1.
0 to 30 kg/cIft, heat and pressure molding for 1 to 3 minutes, and a diaphragm formed from a fiberboard mat is placed at the base of the diaphragm formed at the periphery of the notch of the hard fiberboard. A deep-drawn molded product is manufactured in which the tip of the bottomed cylindrical shape is integrally joined.

As described above, the method of the present invention is to provide a notch in the part of the hard fiberboard that is difficult to draw and mold, soften it with water, and then add a thermosetting resin that is easy to draw and mold. The fiber mat is polymerized and heat-pressed,
The base of the molded part is formed using the softened notch edge of the hard fiberboard, which is easy to mold, and then the tip of the molded part, which is made of fiberboard mat, is joined and integrated by drawing molding. , fairly deep deep drawing molded products can be easily produced.

In addition, since the joint between the hard fiberboard and the mat is provided on the peripheral wall between the base and the tip of the molded part, the joint is more secure than when it is provided at the greatly curved base of the molded part.
Furthermore, the joint between the base and tip of the molded part is made of fibers, so the fibers become entangled.
Together with the adhesive action of the thermosetting resin contained in the mat, it is firmly joined, and the quality is denser and stronger than other parts.

Furthermore, when the part of the hard fiberboard to be molded is soaked in water to soften it, the notch is provided and the inner circumferential surface of the cutout is formed into an uneven surface, making it easy to soak in water.

In addition, the inner circumferential surface of the notch in the hard fiberboard, which will be the end surface for abutment and joining with the mat, is formed into an uneven surface. The fibers flow and fill into the concave part of the part surface, and the abutting joint ends of the hard fiberboard and mat are joined in an interlocking state, so that the molded base of the hard fiberboard and the bottom of the mat made of fiberboard are attached. A deep drawn product is obtained in which the cylindrical drawing tip is more firmly joined and integrated.

Example 1 (See Figures 1 to 4) At the same time, a hardboard 1 for molding with a predetermined shape and dimensions is punched out from a 2.5 m thick hardboard original plate. A notch 2 with a width of 5 m and a length of 3007 rrIn is formed in the part to be molded.

The hardboard 1 provided with the cutout portion 2 is immersed in hot water of 60° C. or higher for 1.5 minutes to contain about 25% water.

Next, 70% wood pulp fiber, 20% phenolic resin,
Hemp fiber 1 has stronger monofilament strength than wood pulp fiber
A mat 3 with a thickness of 15 m, a medium size of 170 m, and a length of 570 m made of 0.0% is placed on a hard board 1 soaked in water with a notch 2.
Cover and place.

Next, the hardboard 1 on which this mat was placed was placed in a drawing press and pressed for 1 minute and 30 seconds under press conditions of 2000C and 20ky/ctl to harden the molded base 5 formed of the hardboard. It has a rectangular drawing molded part 4 with a width of 100 m, a length of 4.0 m (h/vfl), and a depth of 100 m, as shown in Figs. A deep drawing molded product was manufactured.

In this draw molding section 4, the hardboard and the mat were joined by overlapping contact at the peripheral wall portion of the molding section, and the width of the overlapping contact section 7 was about 407 ML.

Embodiment 2 (See FIGS. 5 to 7) As in the previous example, a sawtooth with an uneven amount of 10 to 15 rrrIrL was formed on the molded part of a 2 mm thick hardboard 11 formed into a predetermined shape and size by punching. A notch 12 with a diameter of 140 m and a circumference of 140 m is formed.

This hardboard 11 is soaked in hot water at 80° C. for 1 minute to make it contain about 20% water.

Next, on this water-containing hardboard 11, 75% synthetic fiber,
A mat 13 made of 25% urea resin and having a thickness of 13 m and a diameter of 320 m is placed to cover the notch 12.

The hardboard 11 on which this mat is placed is placed in a drawing press and pressed for 1 minute at 170°C and 215kg/C1ft to form a molded base 15 made of hardboard and a hardened mat. The diameter 2001 shown in FIG.
A deep drawn product having a circular drawn part 14 with Mt and depth of 70 wIL was manufactured.

In this draw molding section 14, the hardboard and the mat were joined by overlapping contact at the peripheral wall portion of the molding section, and the width of the overlapping contact section 17 was about 2.5 m.

The molded products shown in the figures in both of the above embodiments are those in which the molded products were pressed from the birdboard side with a male mold when molding and pressing, but they may also be pressed with a male mold from the mat side.

[Brief explanation of drawings]

Fig. 1 is a plan view of the molding bird board according to the first embodiment, Fig. 2 is an enlarged vertical side view of the molding bird board with the same mat placed on it, and Fig. 3 is a longitudinal sectional front view of the molded product. 4
The figure is a partially cutaway side view of the same molded product, Figure 5 is a plan view of the molding bird board in the second embodiment, Figure 6 is an enlarged vertical sectional view of the molding bird board with the same mat placed on it, Figure 7 is a partially cutaway side view of the same molded product. 1.11... Bird board for molding, 2,12.
...Notch, 3, 13...Matt, 4
, 14... Drawing forming section, 5, 15...
Molded root portion, 6, 16... Molded tip portion, 7.
17...Polymerization contact part.

Claims (1)

[Claims] 1 A notch is provided in the part of the hard fiberboard to be molded, the inner peripheral surface of the notch is formed into an uneven surface, the peripheral edge of the notch is impregnated with water, and a thermosetting resin is applied to the hard fiberboard. A mat containing fibers is placed to cover the notch, and the hard fiberboard on which the mat is placed is heated and press-molded, and the fibers are placed at the base formed by the periphery of the notch in the hard fiberboard. A method for manufacturing a deep-drawn molded product, characterized in that a drawing-molded part is formed by joining and integrating the tip portions formed from plated mats.