JP2006168018A - Mold for manufacturing imitation rush - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for manufacturing an imitation rush comprising a thermoplastic resin. <P>SOLUTION: The mold for manufacturing the imitation rush is constituted so as to continuously mold a plastic raw material comprising the thermoplastic resin and the main body thereof is divided into a plurality of parts in the flow direction of the raw material. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a mold for producing imitation rush made of a thermoplastic resin.

  Recently, imitation rushes that have an appearance similar to natural rushes have been used. This is because it has advantages such as few mites and recent occurrence, almost no fading, and water resistance.

  Of these, many are made of thermoplastic resin. This is because it is easy to manufacture, is inexpensive, and has a good appearance. There are various manufacturing methods, but in each method, a heated mold is finally passed to make the diameter constant, a groove or the like is formed on the surface, or a circular shape is performed.

  Such a mold is a known one, and is simply provided with a tapered through hole. Usually, the final outlet has a diameter slightly smaller than the final diameter of the rush. This is because it spreads and becomes thick immediately after leaving the mold.

However, this conventional mold has the following drawbacks.
First, most of the manufacturing methods for imitation rushes pass the raw material once molded into a rod shape or a film shape through such a mold in order to finally adjust the shape. Therefore, when the mold is heated to such an extent that the raw material melts, when a rod-like or cylindrical one is put in the mold, it melts and sticks at the first contact portion. If this happens, the mold will have to be cleaned without passing smoothly after that.

  To prevent this, at the start, the temperature of the mold is lowered below the melting temperature so that it does not melt even when touched, heated through a part of the raw material after protruding partly from the tip, and the temperature reaches the operating temperature. Is raised. Therefore, there is no problem if it is started up only once a day, but it is necessary to always cool the mold once when a raw material such as a rod is cut, or when the next place is stopped due to various causes. This is not only time consuming but also very wasteful in terms of energy.

  In order to reduce this waste of energy, it is also conceivable to make the mold small so that it can be heated immediately. However, if the mold is made smaller and the heat capacity is made smaller, the temperature is likely to change due to various disturbances, and it becomes difficult to keep the temperature constant. If the temperature is not constant, the appearance will inevitably deteriorate.

  In this imitation rush, an inorganic filler is often mixed as a component in terms of matting and the like. It is like sand and is very hard. Therefore, the mold is inevitably damaged. In order to reduce this, it is conceivable to apply a hard coat to the inside, but it is very difficult and expensive to carry out the inside of a cylinder having a very small inner diameter. Furthermore, it is very difficult to apply a process such as inserting a protrusion on the surface of the rush.

  In view of the current situation as described above, the inventor has completed the imitation rush production mold of the present invention as a result of earnest research, and the feature thereof is that a plastic raw material made of a thermoplastic resin is continuously produced. The main body is divided into a plurality of parts in the flow direction of the raw material.

  Here, polypropylene is suitable as the thermoplastic resin, but other polyolefins, polyamides, and the like may be used, or a plurality of them may be mixed. Various additives such as charcoal cal, rosin, talc and the like may be mixed in the thermoplastic resin. Naturally, since it is an imitation rush, a pigment is appropriately mixed in order to produce a color like a natural rush.

  The plastic raw material is an intermediate that has already been molded into a certain shape, and is introduced into the mold of the present invention. For example, a thermoplastic resin foam rod-like body, a thermoplastic resin tape spirally wound, a thermoplastic resin tape irregularly converged, and the like are not particularly limited.

  Molding such a raw material means determining the shape to some extent, defining the outer diameter, or forming a fusion coating on the surface.

  Among these, a method of irregularly converging the thermoplastic resin tape and forming a fusion film on the surface is preferable. The raw material tape may be manufactured in any way, but is preferably manufactured by inflation processing, and the cylindrical product is cut into a plurality of tapes. As the number to be cut, 2 to 4 sheets were suitable, and 4 sheets were particularly good in the experiment. The thickness of the tape is about 5 to 20 μm. In addition, at the time of inflation processing, it is preferable that the die is provided with protrusions and formed with a large number of irregularities. This is because the surface area of the tape-like body is increased to increase the gap when converged as described later. The stretching of the tape-like body may be about 2 to 7 times in the longitudinal direction.

  Randomly converge means that the tape-like body is not regularly folded or rolled up, but is randomly wrinkled to form an approximately cylindrical body having a tape-like body inside. This method is performed by heating a gap narrower than the tape-like body and passing between the gaps. This is because the surface is fused by heating because there is no shape-retaining property simply by passing it through.

  As for the degree of fusion, when the outer peripheral portion is completely melted and cooled, it becomes a single cylinder, which looks like a conventional PP groom. Also, if the degree of melting is low, it cannot be used because there is no shape retention as described above. Minimal fusion with shape-retaining properties, that is, a fused state in the form of dots, partial lines, or planes, so that air and moisture can pass through. Therefore, the term “fusion” here does not mean that the entire surface is fused, but the appearance is that many longitudinal wrinkles can be seen, and air and moisture can enter inside the wrinkles. State.

  In the mold of the present invention, the main body is divided into a plurality in the flow direction of the raw material. This is a feature of the present invention. If it is divided in the flow direction of the raw material, streaks due to the joints are attached to the product, which is unthinkable conventionally.

The present invention splits this into two or more. This is because it is judged that the streaks that can be formed in the longitudinal direction can be tolerated to some extent by the imitation rush.
Division is the simplest of two, but it may be more. Of course, the division here is to divide the molding part (the inner surface that contacts when the molding object passes), and not to divide only the outer side.

  As a mold, there may be a plurality of molding parts. It suffices if the plurality of molded portions are divided. Further, the divided shape may or may not be the same shape, and the divided shape may be the same shape or not the same shape. Usually, since it is used in close contact, it is preferable that it fits tightly with as little gap as possible.

  The shape of the molded part is free. It may be a simple right circular cylinder, a tapered shape, or a combination thereof. Also, the vicinity of the exit may be enlarged or chamfered. Furthermore, as described above, various hard coats may be applied. For example, superalloy is pasted, baked, and fitted. Further, a groove for providing a streak (protrusion) around the product may be provided, or the cross-sectional shape may be an ellipse other than a circle, a flower shape, a polygonal stripe or the like.

  This mold is provided with a heating device inside or outside thereof. The mold is divided in the heated state, and the raw material can be passed through in that state.

  Although the size of the mold according to the present invention is arbitrary, it is only for imitation rush production, and therefore there is a limitation on the size due to its use. For example, the diameter of the die that is the outlet of the mold is 0.5 to 1.5 mm. The main body is also usually about several centimeters to several tens of centimeters.

  The mold of the present invention is usually formed by passing a raw material, and the raw material passes only once through the mold. However, the same or slightly different molds or sizes may be arranged in series, and the mold that has left the first mold may be passed through another mold again and molded.

The present invention has the following great effects.
(1) Since the mold can be divided in the longitudinal direction, it is not necessary to insert a raw material tape or a rod-like body into a small hole in the first stage. This is a great effect when a new tape is inserted while the mold is heated. That is, when a tape is put into a heated narrow mold, it immediately melts and adheres and is difficult to pass.
(2) Since it is divided, internal machining is very easy.
(3) The entire manufacturing is easy and the cost is reduced.

  Hereinafter, the present invention will be described in more detail based on embodiments shown in the drawings.

  FIG. 1 is a front view showing an example of the mold 1 of the present invention. In this example, two molding parts 2 are provided. In the central lateral direction, the molded part is divided into two parts. Of course, how to divide and how many to divide is free. FIG. 2 is a plan view with the upper member 3 of FIG. 1 removed. The molding part 2 is divided and the inside is visible. This molded part is composed of an entrance side taper part 4, a straight part 5, and an exit side taper part 6. In this figure, the heating device is omitted.

  As can be seen from FIG. 1, the entry side taper portion 4 is provided with eight protrusions so that the surface is streaked. The length ratio of the entry side taper portion 4, the straight portion 5 and the exit side taper portion 6 is 5 to 80 for the straight portion 5 and 3 to 15 for the exit taper portion 6 when the entry taper portion 4 is 100. Is preferred. The diameter of the entrance side taper portion 4 is preferably 5 to 15 mm at the inlet, 0.8 to 3 mm at the final portion, and 0.8 to 3 mm at the straight portion 5, and the diameter of the outlet is 0.9 to 0.9 mm. 3.5 mm is preferred.

  Raw materials (plastic tape, rods, etc.) are introduced from the inlet 7, molded inside, and exit from the outlet 8. Of course, since plastic is molded, there is a part above its melting or softening temperature. If the raw material tape breaks during the manufacturing process, if the tape is put into such a narrow hole, it cannot be smoothly passed through unavoidably, so the tip portion may melt and stick to that portion. When this happens, the machine must be stopped and the inside cleaned. However, in the case of being divided into two as in this example, the raw material can be fitted in a state of being taken out from the outlet instead of being passed through the hole, so that the operation of passing through the hole is unnecessary.

Next, the manufacturing method of the imitation rush which uses this invention metal mold | die is demonstrated.
The imitation rush material is drawn from the storage roll, passes through the mold of the present invention, is molded and cut into a predetermined length by a cutter, and the imitation rush is completed. There is also a type in which weaving with a loom without cutting to a predetermined length and then cutting.
Various processes (heating, cooling such as simple cooling and annealing, cooling, etc.) may be performed between the mold and the cutting or loom.

  FIG. 3 is a perspective view showing the upper and lower members separated from each other. It turns out that the raw material can be fitted immediately.

It is a front view which shows one example of this invention metal mold | die. It is a partial top view of this invention metal mold | die. It is a perspective view which shows the place which divided | segmented this invention metal mold | die.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 This invention metal mold | die 2 Molding part 3 Upper member 4 Inlet side taper part 5 Straight part 6 Outlet side taper part 7 Inlet

Claims (2)

  A mold for producing imitation rushes, which is a mold for continuously molding a plastic raw material made of a thermoplastic resin, the main body being divided into a plurality of parts in the flow direction of the raw material.   The mold for producing imitation rush as claimed in claim 1, wherein the raw material passage portion is coated.

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