JPH0317666B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is applicable to decorative materials, cushion materials, gas-liquid filtration or purification materials, fishery materials such as artificial seaweed attached to artificial fishing reefs, etc., and culverts for civil engineering works. This invention relates to synthetic resin three-dimensional net-like bodies used for drainage materials, etc., particularly those exhibiting a mold-like shape.

(Prior art) So-called mold-shaped moldings with tufted bodies attached around a core have conventionally been constructed mainly by knitting fibers, etc., and those made of synthetic resin are rarely seen. . This is because the structure to be molded from synthetic resin is complex and requires multiple steps, resulting in high costs. By the way, structures exhibiting a molded shape have been mainly used as decorative materials, but by utilizing their structural characteristics, they can also be widely used in industrial applications such as gas-liquid filtration and purification materials. However, as mentioned above, conventional products are mostly composed of knitted fibers, etc., so when used industrially, the core stitches in the center may become uneven or elongate due to the harsh environment. However, there were drawbacks in terms of strength, such as the possibility of cutting or the tufts growing densely around the core falling off. Therefore, there is a strong demand for a molded body that eliminates these drawbacks in terms of strength and can be manufactured at low cost.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to easily and inexpensively manufacture a molded three-dimensional network body using a synthetic resin.

(Means for Solving the Problems) A method for manufacturing a mold-like three-dimensional synthetic resin network of the present invention devised to achieve the above-mentioned object includes A heated melt of thermoplastic synthetic resin is extruded from a nozzle of a required diameter at the required speed, and filaments are spun downward and hang down, and the tips of the filaments in the center are pulled off at a speed higher than the falling speed. Maintaining a straight shape, the filaments at the periphery are irregularly wrinkled by pulling their ends at an appropriately slower speed than the falling speed, and become intertwined with each other to form fused filaments;
It is characterized in that the straight filament at the center and the irregularly crooked and intertwined filaments around it are simultaneously melted and bonded together during the falling process, and then cooled and solidified. It is.

(Example) FIG. 1 is a schematic diagram of the manufacturing process of an example of the present invention, and will be described below in light of the drawings.

1 is an extruder, the inside of which is filled with a heated melt of polypropylene. Nozzles 2, 2' are projected from the lower surface of the extruder 1, and the nozzles 2, 2' are arranged at the center and at a plurality of locations on the circumference surrounding the center. The nozzle 2 at the center has a somewhat larger diameter than the nozzle 2' at the periphery. The nozzles 2, 2' are replaceable, and a desired diameter can be selected and installed. Water tanks filled with cooling water 3 are placed below the nozzles 2, 2' at a required interval. Inside this cooling water 3, take-up rolls 4, 4' are arranged. The extruder 1 can freely set the extrusion speed from each nozzle 2, 2'. The tip of the filament 5 of the polypropylene melt extruded and spun from the central nozzle 2 is pulled off at a speed higher than the falling speed, and the polypropylene melt extruded and spun from the peripheral nozzle 2' is The filament 5' of each nozzle 2,
The extrusion speed and take-up speed of 2' are adjusted and set. That is, the falling speed of the filament 5' in the peripheral part is set to be somewhat higher than that of the filament 5 in the central part. As a result, the filament 5 at the center hangs straight, but the filament 5' at the periphery has to be wrinkled. Due to this wrinkling, the filaments 5' at the periphery are entangled with each other and melted and bonded to form a filament 6, which is also melted and bonded to the straight filament 5 serving as the core at the center. Thereafter, these are introduced into the cooling water 3, cooled and solidified, and the manufacturing process is completed. All that is left to do is to wind it up with a winding roll. FIG. 2 is a partial perspective view of the molded three-dimensional synthetic resin network body manufactured in this manner.

(Operation and Effect) According to the present invention, the filament at the center is taken at a speed higher than its falling speed, and the surrounding filaments are taken at a speed lower than the falling speed, that is, the extrusion speed of the filament at the center is By simply setting the extrusion speed of the filaments on the periphery to a moderately high speed, a mold-like shape can be created that has a straight filament in the center and irregular, wrinkled, intertwined filaments around it. It has the advantage of being able to easily and inexpensively manufacture a three-dimensional synthetic resin net-like body exhibiting the following in one continuous step. In addition, the fabricated mold-like three-dimensional synthetic resin network has a straight synthetic resin filament as its core, making it difficult to stretch and break, and since the surrounding filaments are fused to each other, it is difficult to peel off and its strength is significantly improved. In addition, the desired structure, such as the porosity of the fibers, can be easily obtained by appropriately selecting the nozzle diameter, extrusion speed, and take-up speed, and can be used for a wide range of purposes. There are some effects.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the manufacturing process of the embodiment of the present invention, Figure 2
The figure is a partial perspective view of a molded synthetic resin three-dimensional network body manufactured according to an embodiment of the present invention. 1... Extruder, 2, 2'... Nozzle, 3... Cooling water, 4, 4'... Take-up roll, 5, 5'... Line, 6... Fiber.

Claims (1)

[Claims] 1. A heated melt of thermoplastic synthetic resin is extruded at a required speed from nozzles of a required diameter arranged at multiple locations in the center and around the center, and the filaments are spun and suspended downward. The filament maintains its straight shape by pulling its tip at a speed higher than its falling speed, and the surrounding filaments are irregularly wrinkled and folded into each other by pulling their tips at an appropriately slower speed than the falling speed. The straight core filaments at the center and the irregularly crooked and intertwined filaments around them are simultaneously melted and bonded together during the falling process. A method for producing a mold-like three-dimensional synthetic resin network characterized by solidifying by cooling.