JPH0115619B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is made by molding a bulky nonwoven fabric obtained by mixing a resin component into a fiber component in an open state into an arbitrary irregular shape, and then cutting out the periphery of the molded product. More specifically, the present invention relates to a method for trimming the peripheral edge of a molded part, which shortens the process, reinforces the trim part, covers the trim part with a skin material, and makes it possible to make an acute cut.

Conventionally, thermosetting and/or thermoplastic resins have been added to discontinuous fiber material components such as animal and vegetable fibers such as fallen cotton and waste wool, synthetic resin fiber materials, and/or mineral fiber materials such as glass fibers. A fleece is formed by mixing the powders in appropriate proportions, and then moderate heating is applied to heat-fuse at least a portion of the resin component to a handleable state. Pressure-molded bodies are used, for example, as soundproofing materials for automobiles and buildings.

These molded bodies correspond to the desired shape of unevenness,
Using a mold consisting of an upper mold and a lower mold that can be heated to 150 to 280°C, the upper mold is lowered onto a raw bulky nonwoven fabric placed on the lower mold, e.g. 1 to 150 kg/cm ²
The molded product is compressed for about 1 to 10 minutes with a compression force of It had been trimmed.

However, depending on this cutting method, a phenomenon of interlayer delamination may be observed at the cut end, resulting in weakening of the strength of the edge of the molded product, or in the case of a laminated type with a skin material, the cut end may be covered with the skin material. In addition to poor appearance, peeling of the skin material may be observed.
Problems such as not being able to obtain sharp cuts and easy intrusion of water etc. occur through the cuts, which have extremely unfavorable effects on the performance and durability of the molded product. Furthermore, it required a separate mold and molding machine specifically for trimming, making the process complicated, and improvements were strongly desired in terms of economy and production efficiency.

In view of the current situation, the inventor of the present invention has made extensive studies and has found that the above-mentioned problems can be solved if the peripheral edge of the heated molded product is trimmed at the same time as the molding process, leading to the present invention. The purpose of the invention is to shorten the process, reinforce the trim part, cover the cut end of the trim with a skin material,
It is an object of the present invention to provide an economical and simple method for trimming the periphery of a bulky nonwoven fabric molded article, which enables sharp cuts and various properties such as watertightness of the cuts.

Therefore, the gist of the present invention is that when a molded article obtained by compression molding a bulky nonwoven fabric containing a thermosetting synthetic resin in a heated state is cut into a desired shape, the heated state of the bulky nonwoven fabric is At the same time as the thermosetting resin is melted and hardened during compression molding, the heated press cutting blade is applied to the heated molded body using a pressing cutting blade provided on at least one mold surface, and the thermosetting resin contained is The present invention resides in a method for cutting out a bulky nonwoven fabric molded article by curing a synthetic resin and reinforcing the trim portion while cutting out the mold.

The bulky nonwoven fabric that can be used in the present invention is mainly composed of a binder made of one or more of animal, vegetable, mineral, and synthetic resin discontinuous fiber materials and a thermosetting synthetic resin, and itself It can be obtained by a known method for producing bulky nonwoven fabrics,
Before thermoforming, the binder made of thermosetting synthetic resin is in an uncured state, and it can be made into a bulky nonwoven fabric by melting the thermosetting synthetic resin or by other means such as using a thermoplastic synthetic resin together. It is important to keep it in a condition where it can be handled.

The bulky nonwoven fabric in this state generally has a thickness of 8 to 50 m/m and an areal density of 400 to 4000.
It is preferably in the range g/m ² .

In the present invention, such a bulky nonwoven fabric may be heat-molded and used as it is, but when a bulky nonwoven fabric made of a flammable material is used, a flame-retardant or non-flammable thin nonwoven fabric is used. It is possible to heat-form the fabric after pasting it, or to heat-form it after applying a flame retardant, or to heat-form the bulky nonwoven fabric as it is and then apply a flame-retardant treatment agent or fluff prevention agent. There is no problem with applying a chemical agent or the like, and it may even be preferable in some cases. It is also effective to apply waterproofing.

The molding machine that can be used in the present invention may be one that is conventionally known, and consists of an upper mold and a lower mold corresponding to the desired shape, and generally the upper mold moves up and down and the molding machine is placed on the lower mold. A molded product having a desired shape may be obtained by compressing the bulky nonwoven fabric with a compression force of about 150 kg/cm ² or less for about 30 seconds to 10 minutes using an upper die lowered onto the original bulky nonwoven fabric. The temperature of the mold used at this time may be any mold that can be heated to a temperature range of approximately 150 to 280°C.

In the present invention, it is essential to provide a punching blade on the surface of the mold of the above-mentioned molding machine, and to perform trimming at the same time as molding. The push-cutting blades are provided corresponding to the outer periphery and internal punch-holes or simple notches (slits) of the desired molded body, and may be provided on either the upper mold or the lower mold. At the same time as molding, it is necessary to apply a heated push-cutting blade to the heated molded body for trimming, so the trimming part is heated more intensively by the pushing-cutting blade, and the thermosetting resin in that area is sufficiently melted and hardened. In addition to significantly increasing the strength, the cut ends are sufficiently impregnated or coated with the molten resin to effectively prevent liquid from entering through the trim cut ends.

In addition, when a bulky nonwoven fabric and a skin material or thermoplastic film are simultaneously molded and bonded, a push-cutting blade is provided in the mold on the side that contacts the skin material or thermoplastic film, and simultaneous trimming is performed according to the method of the present invention. In this case, the skin material or thermoplastic film wraps around the cut end and sufficiently covers the cut end, resulting in a molded product with an extremely good appearance, and prevents the problem of the skin material or thermoplastic film peeling off during long-term use. effective.

Furthermore, since the trimming method of the present invention performs trimming simultaneously with molding, it does not need any explanation that it directly leads to a reduction in process steps. Needless to say, there is no need for a conventional molding machine equipped with a mold exclusively for trimming, making it extremely economical.

The mold used in the present invention is provided with a press-cutting blade of a desired shape, and the press-cutting blade may be provided on either the upper mold or the lower mold. Preferably, it is the surface in contact with the skin material. It is preferable that the mold is provided in either the upper mold or the lower mold, and that the other mold is preferably made of a cast material that is softer than the material of the blade material, especially the surface that contacts the cutting edge of the push-cut blade. Prevents wear on the cutting edge and extends the service life of the mold. The push cutting blade may be provided embedded in the mold, or may be provided integrally when forming the mold. The angle of the cutting edge viewed from the cross-sectional shape of the push-cutting blade is preferably 0 degrees to 90 degrees. More preferably it is 5 degrees to 45 degrees. Further, the cross-sectional shape of the push-cutting blade may be chevron-shaped, and one side thereof may be at a substantially acute angle with respect to the mold surface.

In the simultaneous trim method of the present invention, compression force, mold temperature, molding time, etc. may be the same as conventional conditions.

Examples are given below to provide a more detailed understanding of the present invention. Naturally, the present invention is not limited to the following examples.

Example 30 parts by weight of recycled wool and 50 parts by weight of fallen cotton were opened and mixed to melting point
20 parts by weight of phenolic resin powder with a reaction temperature of 215°C was sprinkled and mixed at 180°C, formed into a fleece using a fleece forming machine, and passed through a heating furnace at 185°C to a thickness of 30 m/m.
A bulky nonwoven fabric with an areal density of 1150 g/m ² was obtained.

Next, from the bonnet mold, four approximately truncated pyramid-shaped overhangs with a height of 20 m/m excluding the thickness of the molded body were made to correspond to the substantially flat parts divided into four sections by the intersecting reinforcing members. and the thickness of the flat part is set to 3 m/m to correspond to the reinforcing member of the bonnet and the periphery of the molded body.
When molding is performed under heating conditions of 230℃, a blade material with a height of 3 m/m and a cross-sectional shape angle of approximately 45 degrees is provided on the mold surface of the upper mold to correspond to the flat area around the molded object. Using an upper mold, heat and pressure molding was carried out for about 1 minute at a compression force of about 5 kg/cm ² .

When the upper mold was raised, the trim part of the molded product was completely cut at an acute angle, and the thermosetting resin at the cut end was sufficiently melted and solidified, resulting in excellent strength and watertightness at the end of the molded product. It has become clear that molded products can be obtained efficiently and economically in one process.

Claims (1)

[Claims] 1. When molding a molded article obtained by compression molding a bulky nonwoven fabric containing a thermosetting synthetic resin in a heated state into a desired shape, the thermosetting resin is compressed during compression molding of the bulky nonwoven fabric in a heated state. At the same time as melting and curing, the heated press cutting blade provided on at least one mold surface is applied to the heated molded body to harden the thermosetting synthetic resin contained therein, thereby forming a trim part. A method for cutting out a bulky nonwoven fabric while reinforcing the molded article.