JPS63256411A - Preparation of hollow body having inter pattern - Google Patents

Abstract

PURPOSE:To make it possible to form an inner hollow pattern prepared by transferring an inner mold and to manufacture a hollow body having an inner pattern with complicated processes, by inserting an inner mold in an inner molding space of a mold, pouring and solidifying a molding material in the molding space in this state and thereafter dissolving the inner mold. CONSTITUTION:A gelatin solution is poured in a plaster mold being capable of splitting into right and left molds to prepare a golf ball-like inner mold 3. Then, the inner mold 3 is inserted in an space of a mold 1 for molding a cylinder being capable of splitting into a top and a bottom molds and therein hanged with a string. In this state, a transparent synthetic resin molding material is the in poured from a pouring hole 2 for a molding material and solidified. The mold 1 is opened to take out a cylindrical molded item and a dissolving hole 4 reaching the golf ball-like inner mold 3 is perforated. A small injection needle is inserted in this dissolving hole 4 and while gelatin is being dissolved by pouring hot water, dissolved gelatin is flowed out of a gap between the outer circumference of the injection needle and the dissolving hole 4 to form a golf ball-like hollow pattern space after the outflow. A resin is poured in the dissolving hole 4 only to bury the dissolving hole 4 to form a golf ball-like pattern space.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing hollow bodies with internal patterns used for decoration, display containers, etc.

[Conventional technology]

In the conventional method for manufacturing a molded body with a three-dimensional pattern inside, the only option was to embed the three-dimensional pattern itself into the molded body. In other words, it was not possible to obtain a product in which the pattern was formed by internal hollow spaces.

[Problem that the invention seeks to solve]

As described above, no method for producing a hollow body in which a pattern is formed in the internal hollow space has been developed so far, and there is a strong demand for the development of this method.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a hollow body with a pattern inside without going through complicated steps.

[Means for solving problems]

In order to achieve the above object, the method for manufacturing a hollow body with an internal pattern of the present invention is to place an internal mold formed of a soluble substance in an internal molding space of a mold at a predetermined distance from the inner wall surface of the internal molding space. In this state, the molding material is injected into the molding space inside the mold and solidified to form a molded body.Then, the internal mold inside the molded body is melted and the molded material is inserted into the molded body. The structure is such that a hollow space is formed from the melted remains of the mold.

That is, in the molding method using a mold, the present inventor
As a result of a series of studies to form patterns in the internal hollow space, we inserted an internal mold made of a soluble material into the internal molding space of the mold, and in that state, we filled the molding material into the molding space. After injecting and solidifying, when the inner mold is melted using a method appropriate for the material, the space formed along the shape of the inner mold at the melting mark creates an interior in which the external shape of the inner mold is faithfully transferred to the hollow wall surface. This invention was achieved by discovering that a hollow pattern is formed.

The soluble substances forming the internal mold of the present invention are generally classified into the following two types depending on the molding material for forming the hollow body injected into the internal molding space of the mold.

When plastic is used as the molding material for forming the hollow body, gelatin and gypsum (
CaSOa) etc. are used. Furthermore, when the molding material is inorganic such as glass, gypsum or the like is generally used.

Using such raw materials, a hollow body with an internal pattern can be manufactured, for example, as follows. That is, an internal mold with a desired pattern is formed in advance using a mold for forming an internal mold made of a soluble material, and when assembling the mold to be divided into two for forming a hollow body, the molding material injection hole, etc. Suspend through. Next, in this state, a molding material is injected into the mold through the injection hole and solidified. After solidification, a hole is made from the injection hole to reach the soluble substance inside, and the internal mold containing the soluble substance is removed by melting or the like using a method depending on the material, leaving a hollow pattern behind the removal. If this soluble substance is removed after the molding material has solidified into a molded body, there is no problem whether the molded body is removed before or after the molded body is removed from the mold.

A method for removing the above-mentioned internal mold made of a soluble material from a molded body by melting or the like will be explained. First, when gelatin is used as the soluble substance, boiling water is poured into a syringe fitted with a small-diameter injection needle, and a hole is made through the molding material injection hole to reach the soluble substance, and the boiling water is poured into the syringe. The dissolved gelatin solution flows back from the outer periphery of the needle and the solution is eluted.When gypsum is used as the soluble substance, there are two methods. First 120″C
When gypsum calcined by heating to the above temperature is used, the gypsum is melted in the same manner as the gelatin described above, replacing the hot water with a sodium thiosulfate (NazStO3) aqueous solution. Another method is to use at least one of ultrasonic waves and high frequency waves to finely crush gypsum, make a hole that reaches the soluble substance from the molding material injection hole, and take out the gypsum object from the hole. Next, the elution hole from which the soluble substance was taken out is filled by discharging a molding material of the same quality as the molding material from a syringe needle.

The internally patterned hollow bodies obtained in this way are usually
It is a transparent product, and the hollow pattern inside can be clearly seen through the transparent part, so it can be used for various decorations and displays.

〔Effect of the invention〕

According to the present invention, a hollow body with an internal pattern is manufactured as described above, and an internal pattern consisting of hollow spaces can be easily formed inside the molded body using a plastic molding material or the like. By changing the external shape and outer surface pattern of the internal mold made of a soluble material, these shapes can be faithfully transferred to the hollow wall surface of the hollow space, and a wide variety of internal hollow patterns can be formed. become. As an application thereof, by injecting a decorative solution into the internal hollow pattern, it is possible to provide products with rich decorative properties. Further, for example, when a soluble substance such as gelatin is used in the internal mold, it can be recycled after use, so it can be used repeatedly, and costs can be reduced.

Next, the present invention will be explained based on examples.

[Example 1] Using a golf ball, the periphery of the golf ball was hardened with plaster to create a left and right plaster mold for forming an internal mold, and a gelatin solution was sealed in this plaster mold to prepare a golf ball-shaped internal mold. Next, as shown in FIG. 1, the internal mold 3 was placed in the internal space of the cylinder-forming mold 1 which was divided into upper and lower halves and hung with a thread.

In this state, a transparent synthetic resin molding material was poured through the molding material injection hole 2 and allowed to solidify for several hours. Then,
The mold 1 was opened, the cylindrical body was taken out, and elution holes 4 reaching the golf ball-shaped inner mold 3 were bored as shown in FIG. Then, a small-diameter injection needle is inserted into the elution hole 4, and while boiling water is injected to dissolve the gelatin, the dissolved gelatin solution is poured out from the gap between the outer periphery of the injection needle and the elution hole 4, and a golf ball is placed in the flow trace. A hollow space (
pattern space) was formed. Next, the cylindrical body was placed on its side, and a plastic resin of the same quality as the molding material was poured into only the elution holes 4 using a small-diameter injection needle to fill the elution holes 4. In this way, a hollow body having a golf ball-shaped patterned space formed inside was obtained.

[Example 2] A spherical internal mold made of gypsum (CaSO4) was prepared. Next, the above internal mold was placed in the internal space of the cubic mold and suspended. Then, a transparent synthetic resin molding material was poured into the mold through the molding material injection hole of the mold and left for several hours to solidify.

Next, the transparent cubic molded body was taken out of the mold, and a relatively large diameter elution hole was bored so that it could function as a flower vase. A syringe needle was inserted into this elution hole, and sodium thiosulfate (CNazStOs') was injected to dissolve the gypsum. The dissolved gypsum solution was poured out through the elution hole. In this way, transparent containers such as a flower vase, a cosmetic container 2 and a food container as shown in FIG. 3 were obtained.

[Example 3] The internal mold with a golf ball pattern was replaced with a bolt pattern. Other than that, a hollow body for a display having a bolt pattern inside was obtained in the same manner as in Example 1. This is shown in FIG.

[Example 4] An internal mold was prepared in which a paint film was applied to the surface of a doll made of gelatin. Other than that, the same procedure as in Example 1 was carried out.
A hollow body for display with a Daruma pattern inside was obtained. At this time, the heat of the injection molding material transferred the paint film to the wall surface of the pattern space of the molded body, giving the impression that the Daruma doll was actually embedded. This is shown in FIG.

In addition, in the above explanation, a transparent hollow body is manufactured using a transparent molding material, but it is also possible to use an opaque molding material to enlarge the internal pattern space and use it, for example, as a space for filling reinforcing material. It's okay.

[Brief explanation of drawings]

Figure 1 is an illustration of an internal mold formed of a soluble substance in the internal molding space of the mold, Figure 2 is a diagram of elution hole formation in a cylindrical molded body, and Figures 3, 4, and 5 are It is an explanatory view of another example. 1... Mold 2... Molding material injection hole 3... Internal mold 4... Elution hole Figure 1 Figure 2 Figure 4 Figure 5

Claims (2)

[Claims] (1) Insert an internal mold formed of a soluble substance into the internal molding space of the mold while maintaining a predetermined distance from the inner wall surface of the internal molding space, and in this state, A hollow body with an internal pattern is formed by injecting a molding material into the molded body and solidifying it to form a molded body, and then melting the internal mold inside the molded body to form a hollow space formed by the melted trace of the internal mold inside the molded body. Manufacturing method. (2) A method for manufacturing a hollow body with an internal pattern according to claim 1, wherein the molding material is transparent.