JPS583810B2 - Ishiyokunotatejimamoyououusuru - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a hollow molded product in which a vertical striped pattern of a different color is formed on the body part, but the vertical striped pattern of a different color is not formed on the mouth part.

Hollow molded products with a mouth smaller than the body made of synthetic resin are often used as containers for cosmetics, medicine, etc. However, if the entire container is the same color, it will become too simple and the container will not look good. Some containers have a unique vertical striped pattern around their outer periphery.

Conventionally, a method of manufacturing a hollow molded product having a unique vertical striped pattern using a blow molding method is known, but the vertical striped pattern of the hollow molded product obtained by the conventional manufacturing method is different from the blow molding, as shown in Figure 1. Vertical stripes were formed not only on the body of the product, but also on the mouth of the hollow molded product.

However, such a hollow molded product in which a continuous vertical striped pattern is formed on the mouth and body has the disadvantage that it is very unsightly.

In other words, from the viewpoint of decorative effect, the vertical striped pattern is formed only on the body, the vertical striped pattern is eliminated from the mouth, and the mouth is made of a single color with no pattern for a cleaner and better appearance. Body of molded product: There has been a need for a method for manufacturing a hollow molded product that has a vertical striped pattern on the body, but has no single-color vertical striped pattern on the mouth.

The present invention was made in view of the above circumstances, and its purpose is to ensure that a hollow molded product having a vertical striped pattern on the body part, but with a single color and no vertical striped pattern on the mouth part, is produced using a blow molding method. Another object of the present invention is to provide a method for manufacturing a hollow molded product having a unique vertical striped pattern that can be manufactured efficiently.

Details of the method for manufacturing a hollow molded product having a mouth smaller than the body of bottles and other objects according to the present invention, that is, a hollow molded product having a vertical striped pattern on the body but not on the mouth, as described above. Specifically, first, a parison is molded which has an outer diameter larger than the outer diameter of the mouth of the hollow molded product and smaller than the outer diameter of the body of the hollow molded product.

In other words, when split molds for blow molding are combined, the mold has an outer diameter larger than the inner diameter of the part where the mouth of the hollow molded product is formed, and at the same time, A parison is molded having an outer diameter smaller than the inner diameter of the mold in which the body of the hollow molded product is to be formed.

To explain this with reference to FIG. 2, if the outer diameter of the parison 1 is D, this D is larger than the diameter d of the hollow molded product mouth forming part 3 of the split mold 2, and The parison 1 is formed to have a diameter smaller than the diameter d' of the molded product body forming portion 4.

The mold 2 is formed with a fillet relief part 5 that is continuous with the hollow molded product mouth forming part 3. Therefore, when blow molding is performed by aligning the split molds and blowing air into the hollow molded product, the hollow molded product The parison part that will form the body is expanded by air and comes into close contact with the mold to form the body, while the parison part that will form the mouth of the hollow molded product is joined by the split mold. At this time, since the outer diameter of the parison is larger than the inner diameter of the mouth forming part of the mold, the excess synthetic resin escapes from the mold splitting part of the mold as paris to the relief part 5 of the mold, while forming the mouth of the hollow molded product. This will form a section.

Note that in order to form the parison as described above, you can either form the parison into the above shape as it is extruded with an extruder, or blow air into the hollow part of the parison that is still extruded with an extruder. A parison having the above-mentioned shape is then formed.

Furthermore, when molding the above-mentioned parison 1, this parison 1
A unique vertical striped pattern is formed along the axial direction on both sides of the outer periphery of the parison 10. This method of forming is a conventionally commonly used method. In a molten state, it is sequentially extruded from a ring-shaped channel along the axial direction of the ring-shaped channel, and at two opposing locations (shifted by 1800 degrees from each other) on the outer circumferential side of the ring-shaped channel. A material that provides two small channels, communicates these small channels with a ring-shaped channel, and forms a vertical striped pattern 7 from these small channels, that is, a molding material that forms the main body 6. When molding materials made of different colored synthetic resins are extruded in a molten state, and this material with a vertical striped pattern is fed into the material for the main body which is sequentially flowing through a ring-shaped channel, a cylinder is formed as shown in Figure 3. Two unique vertical striped patterns 7 are formed on both sides along the axial direction of the main body 6 which is extruded into a shape, and when the parison 1 having the vertical striped pattern is formed, is formed so that it is located at the mold part of the mold.

The molding material for the parison 1 may be any synthetic resin that can be blow molded, such as polyethylene, polypropylene, polycarbonate, nylon, cellulose acetate, etc., and if necessary, plasticizers, stabilizers, fillers, etc. Add coloring agent, etc.

Immediately after molding, the parison 1 formed as described above is set in a split mold 2 for blow molding, but at this time, the vertical striped pattern 7 of the parison 1 is placed at a position corresponding to the split part of the mold. In this state, the split mold 2 is joined.

Then, since the parison 1 has an outer diameter D larger than the outer diameter d of the mouth forming part 3 and smaller than the outer diameter d' of the body forming part 4, the opening of the parison 1 The outer casing part of the part corresponding to the body part forming part 3 bites into the mold split part, and the unique vertical striped pattern of this part is also discharged as a part to the relief part 5, and it is still in the body part forming part 4 of the parison 1. The corresponding part remains intact and is retained in the body-forming part 4 of the mold, while the lower part of the parison 1 is cut off by the mold and simultaneously closed to form the bottom.

In addition, to explain the above state using a drawing, parison 10
The vertical striped pattern 7a corresponding to the mouth part is discharged as parison, the vertical striped pattern 7b corresponding to the body part remains, and the lower part 8 of the parison 1 is cut off.

After joining the split molds, when blow molding is performed by blowing air in, the parison 1 expands with the air and is crimped to the inner surface of the mold to form a hollow molded product. A hollow molded product is obtained which has a vertical striped pattern of a different color, but has a single color with no pattern at the mouth and does not have a vertical striped pattern of a different color.

Fig. 5 shows this.A unique vertical striped pattern 7 is formed on the body part 9 of the hollow molded product, but a unique vertical striped pattern 7 is formed on the mouth part 10 of the hollow molded product. A vertical striped pattern 7a is formed in the burr 11.

Therefore, by removing the generated burrs 11 after blow molding, a hollow molded product can be obtained which has vertical stripes of a different color on the body of the hollow molded product and does not have vertical stripes of a different color on the mouth of the hollow molded product.

As described above, the hollow molded product obtained by the present invention has a unique vertical striped pattern on its body, but has a unique vertical striped pattern on its mouth. Compared to hollow molded products, which also have a unique vertical striped pattern on the mouth, they are cleaner and more beautiful.

Therefore, according to the present invention, hollow molded products such as bottles with excellent decorative effects and high commercial value that meet the tastes of consumers can be obtained.

In addition, since the vertical striped pattern corresponding to the mouth part only needs to be discharged as dust when joining the split molds, manufacturing is easy and efficient, and conventional equipment can be used with almost no changes, making it convenient. It is.

In addition, in the above example, a case was described in which two linear patterns were formed on each side as a unique vertical striped pattern, but this pattern may have one or more than two lines, and the pattern itself may be slightly inclined. There is no problem even if the vertical stripe pattern and the parting line of the mold are slightly misaligned.The point is that when the molds are put together, only the vertical stripe pattern at the mouth part is discharged as burr. Bye.

For example, if a hollow molded product is molded in the same manner as described above using four split molds made by dividing the mold into four parts at 90° each, the body of the hollow molded product will have positions shifted by 90° from each other. A hollow molded product is obtained that has a unique vertical striped pattern on the outside but has no vertical striped pattern on the mouth part.

[Brief explanation of drawings]

Fig. 1 is a front view of a hollow molded product molded by a conventional method, Fig. 2 is a cross-sectional view showing an embodiment of the extrusion-molded parison and split mold of the present invention, and Fig. 3 is a front view of a hollow molded product molded by the conventional method. FIG. 4 is a perspective view showing an embodiment of an extruded parison, FIG. 4 is a front view showing an embodiment of a blow molded product according to the present invention before the parison is removed, and FIG. FIG. 2 is a front view showing an example of a hollow molded product. 1...Parison, 2...Split mold, 3.
...Hollow molded product mouth forming part of split mold, 4...
・Hollow molded body part forming part of split mold, 5...
Flesh relief part, 6...Parison body, 7...
・Unique vertical striped pattern, 8...lower parison, 9・
...Body part of hollow molded product, 10... Mouth part of hollow molded product, 11...Flash.

Claims (1)

[Claims] 1. When manufacturing a hollow molded product by the blow molding method, a split mold is formed in which a mold split part as a relief part is placed at a symmetrical position corresponding to the mouth of the hollow molded product, The parison immediately before being set in this split mold is extruded so that it has an outer diameter larger than the outer diameter of the mouth of the hollow molded product and smaller than the outer diameter of the body of the molded product. The parison is formed to have a vertical striped pattern of a different color along the vertical stripes, and the parison is set in a split mold with the vertical striped pattern of the parison located at a position corresponding to the split part of the mold, and the split molds are joined. By letting only the part of the parison corresponding to the mouth of the hollow molded product flow into the mold splitting part and biting it in, the outer periphery of the parison containing a unique vertical striped pattern is discharged as paris in the gap of the mold splitting part. Then, the body and mouth of the hollow molded product are simultaneously molded by blow molding the parison in the mold, and a unique vertical striped pattern is formed on the body of the hollow molded product, and a uniquely colored vertical striped pattern is formed on the mouth of the hollow molded product. A method for producing a hollow molded product having a unique vertical striped pattern, characterized by avoiding the formation of a vertical striped pattern.