JPS6112311A - Method for molding multicolor resin container - Google Patents

Abstract

PURPOSE:To easily mold a container having different colors by integral molding, by a method wherein a first synthetic resin is injected in a frame shaped cavity in such a state that a slide core is present at an advance position and, subsequently, a second synthetic resin is injected in at least one of a bottom plate cavity and a top plate cavity while a third synthetic resin is injected in the other cavity in such a state that the slide core is present at a retracted position. CONSTITUTION:After first and second slide cords 32, 33 are moved to advance positions, a first synthetic resin P1 is injected in a frame shaped cavity C1 from a first gate G1 and, subsequently, the slide cores 32, 33 are moved to retracted positions to inject a second synthetic resin P2, which is prepared by coloring the resin having compatibility with the first syntheric resin P1 with a different colorant, in a bottom plate cavity C2 from a second gate G2 and, in parallel to this, a second synthetic resin P3 having a color different from the colors of both first and second synthetic resins is injected in a top plate cavity C3 from a third gate G3 to mold a three-color synthetic resin container.

Description

Detailed Description of the Invention "Industrial Application Field" The present invention provides a container made of synthetic wood J1w, which has a container body, a lid, and a thin-walled hinge that integrally connects them. make it possible to do so. This invention relates to a method of molding a multicolored resin container.

``Prior Art'' For example, as shown in FIG. 5, there is a known synthetic resin container for storing cosmetics, etc., in which a container body 1 and a lid 2 are integrally connected by a thin hinge 3. It is being In this type of container, in order to give it a luxurious feel and a variety of colors, for example, the container body 1 and the lid 2 are molded from synthetic resins of different colors.

6 and 7 show a conventional example of the molding method, in which a container cavity 6, a lid cavity 7 and a hinge cavity 8 are formed between a cavity mold 4 and a core mold 5, and m7 As shown in the figure, slide pin 9
With the container cavity 6 and lid cavity 7 separated by This is a method of injecting a second synthetic resin P of a different color from the first synthetic resin from the second sprue 11, thereby obtaining a two-color synthetic resin container with the structure shown in Figure 5. .

``Problems to be Solved by the Invention'' However, with such conventional molding methods, due to the structure of the mold used, basically the molding of containers in two colors is the limit. It is impossible to integrally mold containers with more different colors, and therefore, there is a problem in that it is not possible to fully satisfy this type of container, which is important from a design standpoint. In addition, in this conventional mold, as a means for separating the container cavity 6 and the lid cavity 7, the boundary portion between the container cavity 6 and the hinge cavity 8 (the portion corresponding to the peripheral wall of the container body) is inserted into the cavity. Due to the structure in which the sliding pin 9 is moved forward and backward, there is a problem in that it may not be possible to move the sliding pin 9 forward and backward depending on the wall thickness and cross-sectional shape of the peripheral wall of the container to be molded. There was also.

Therefore, according to the present invention, containers having two or more different colors can be easily formed by integral molding, and this can be realized by extremely easy means from the viewpoint of the structure of the mold. Furthermore, the purpose is to provide a molding method that is not affected by the shape of the container to be molded.

[Means for Solving the Problem] In the present invention, at least one of the cavity mold and the core mold constituting the mold is provided with a sliding core that can freely move forward and backward into the cavity, and the sliding core is in an advanced position. A frame-shaped cavity is formed for molding the peripheral walls of each of the container body and the lid, and a thin hinge that integrally connects the lid to the container body so that the lid can be opened and closed. A molding apparatus in which a bottom plate cavity and a top plate cavity are respectively formed for molding the bottom plate part and the top plate part of the lid body, and a sprue is opened in each of the frame-shaped cavity, the bottom plate cavity, and the top plate cavity. First, the first synthetic resin is injected into the frame-shaped cavity at the forward position of the sliding core, and then, at the retracted position of the sliding core, the first synthetic resin is injected into at least one of the bottom plate cavity and the top plate cavity. The second synthetic resin,
A method was adopted in which a third synthetic resin was injected into the other to mold synthetic resin containers of at least two colors.

"Example" Fig. 3 shows the structure of a multicolored resin container obtained by the molding method according to the present invention.The container according to this illustrated example also basically consists of a container body 1, a lid body 2, and these. Although the structure has a thin hinge 3 that is integrally connected, the peripheral wall 1aS of the container body 1, the right side of the peripheral wall @211 of the lid body 2 and the thin hinge 3 are formed of the first synthetic resin P1,
In addition, the bottom plate portion Ib6 of the container body 1 is made of a second synthetic resin P,
further, the top plate portion 2b portion of the lid body 2 is formed of a third synthetic resin P, and these first
, the second and third synthetic resins P, , P, and P3 are
They are different from conventional containers in that they all have different colors, thereby forming three-colored resin containers.

Next, an example of a molding apparatus (mold) suitable for carrying out the method for molding this three-color resin container is shown in Figure 1 (and ()).
This will be explained with reference to 1). This 11th figure (ri and (1)
, 2o is a cavity type, and 30 is a core type. The core mold 3o has a base core 31 that is matched with the cavity mold 20.

A first sliding core 32 and a second sliding core 33 are provided on the base core 31 and are movable into the cavity.
It is composed of. Both sliding cores 32,
A frame-shaped cavity C3 is formed for forming the thin-walled hinge 3 as shown in FIG. 1(1), while both sliding cores 32 and 33 are formed as shown in FIG. When in the retracted position, there is a frame-shaped cavity C1 in this mold.
In addition to that.

Bottom plate cavity C for molding the above-mentioned bottom plate part 1b
1 and a top plate cavity C1 for molding the top plate part 2b are respectively formed. Further, the cavity mold 20 includes a first sprue G that opens into the frame-shaped cavity CI.

and a second sprue G opening into the bottom plate cavity C8.

and a third sprue G opening into the top plate cavity C1.

Each of these sprues G, , G, , G is connected to a respective injection machine (not shown) through its own runner.

In order to mold the container shown in FIG. 3 using the molding apparatus configured as described above, first, step 1. Second sliding core 32.3
3 in the forward position shown in Figure 2 (1), and
A synthetic resin P made of, for example, polypropylene resin colored in a desired color is injected into the frame-shaped cavity C1 from the first sprue G1, and then the sliding cores 32 and 33 are injected into the frame-shaped cavity C1.
From the second sprue G, after placing it in the retreating lid shown in Figure (1).

A second synthetic resin P, which is made by coloring the same or different resin that is compatible with the first synthetic resin P, in a different color is injected into the bottom plate cavity C8. 3 sprue G, and a third synthetic resin P having a different color from both the first and second synthetic resins into the top plate cavity C3.
After cooling the mold for a required period of time, the cavity mold is opened and the sliding core is moved forward to remove the mold, thereby molding the three-colored synthetic resin containers shown in FIG. 3.

Here, the second and third synthetic resins P,,P.

If synthetic resin of the same color is used for the bottom plate part 1b and the top plate part 2,
A container is molded in which b is the same color and has two different colors from the rest of the container.

According to this embodiment, the construction and operation thereof can form the three cavities necessary to obtain containers of three colors simply by sliding the sliding cores 32, 33 together into their forward and retracted positions. It is not unreasonable to do so, and therefore, even when molding a container, etc., in which the wall thickness and cross-sectional shape of the peripheral wall of the container to be molded vary widely, it is impossible to form a cavity that fully accommodates these changes. It can be achieved without any problem. Furthermore, when the first NI moving core 32 and the second sliding core 33 are configured separately as in the embodiment, by adjusting the respective retracted positions of both sliding cores.

There is an advantage that the thickness of the bottom plate part 1b and the top plate part 2b can be adjusted freely as required, and there is also an advantage that the sliding cores 32 and 33 can be used for ejecting molded products.

Fig. 4 (1) e (1) shows another embodiment of the molding equipment # (mold) used to carry out the molding method of the present invention. Even at 20,
Third and fourth sliding cores 22 and 23 are provided at positions facing the first and second sliding cores 32 and 33 of the core mold 30, respectively.
are provided respectively, and the third and fourth sliding cores 22, 2
3. The outer diameter of each of the 1st and 3rd. Second sliding core 32.
The molding apparatus differs from the molding apparatus of the embodiment shown in FIG. 1 and the second block in that the molding apparatus is configured to have a slightly smaller diameter than the outer diameter of each of the molding apparatuses 33 and 33.

If a molding apparatus having such a configuration is used, when forming the bottom plate cavity C1 and the top plate cavity C3, the first
．． The second sliding cores 32, 33 and the third. 4th sliding core 2
The first synthetic resin P is injected by sliding each of 2.23 in a direction that separates them from each other by half the wall thickness of the bottom plate part 1b and top plate part 2b of the corresponding container.

The cross-sectional shapes of the fused portions of the second and third synthetic resins p, , p, respectively, can be shaped so that their convexes and convexities engage with each other, as shown in FIG. 4 (II). There is an advantage that the strength of the fused portion can be improved.

In the embodiment, the first and second sliding cores are constructed separately, and the third sliding core is constructed separately. Although the fourth sliding core is also constructed separately, it goes without saying that these may be constructed integrally.

"Effects of the Invention" In the present invention, at least one of the cavity mold and the core mold constituting the mold is provided with a sliding core that can move forward and backward into the cavity, and in the forward position of the sliding core, the container body and A frame-shaped cavity is formed for forming each peripheral wall of the lid and a thin hinge that integrally connects the lid to the container body in an openable and closable manner. A bottom plate cavity and a top plate cavity for molding the top plate portion of the lid body are respectively formed, and a molding device RIT is used, which has a sprue opened in each of these cavities. First, the sliding core is moved forward. Injecting the first synthetic resin into the frame-shaped cavity at the position,
Next, in the position where the sliding core is retracted, a second
Since the method of molding synthetic resin containers of at least two colors by injecting a third synthetic resin onto the other synthetic resin, two
Containers with different colors can be easily formed by integral molding, and this can be achieved by extremely easy means due to the structure of the mold and moldability, and furthermore, the containers to be molded can be easily formed by integral molding. This method has an excellent effect in that it is possible to obtain a method for molding a good multicolored resin container that is not affected by the shape of the container.

[Brief explanation of drawings]

Figures 1 to 4 show embodiments of the present invention. Figure 1 (1) j (It) is a cross-sectional view of the molding device, Figure 2 (1) e (1) is a cross-sectional view for explaining the molding method, and Figure 3 is a molded container. A sectional view of FIG. 4 (1) t (1) is a sectional view showing other embodiments of the molding apparatus, FIGS. 5 to 7! FIG. 5 is a cross-sectional view of the container, and FIGS. 6 and 7 are cross-sectional views, respectively, showing a conventional molding method. 1... Container body, 1a... Bulky wall part, 1
b...Bottom plate part, 2...Lid body, 2a...
...Peripheral wall part, 2b...Top plate part, 3...
...Thin hinge %P1...First synthetic resin. P! ...Second synthetic resin, P, ...Third synthetic resin, 20...Cavity m% 22
...Third sliding core, 23...Fourth sliding core, 30...Core type, 31...Base core, 32... ...First sliding core, 33...
・・Second sliding core, CI・・・・Frame cavity%
C1... Bottom plate cavity s C1...
Top plate cavity. G1...First sprue, G! ...Second sprue, Gs...Third sprue. Figure 1 Figure 2 (Engineer) Figure 3 3 (P+)

Claims (1)

[Claims] (1.) A cavity for molding a container body, a lid, and a thin hinge that integrally connects them is formed in a mold, and a cavity mold and a core that constitute the mold are provided. At least one of the molds is provided with a sliding core that can move forward and backward into the cavity, and in the advanced position of the sliding core, a frame for molding the peripheral wall portions of each of the container body and the lid body and the thin hinge is provided. A shaped cavity is formed, and in the retracted position, a bottom plate cavity and a top plate cavity are respectively formed for forming the bottom plate part of the container body and the top plate part of the lid body. uses a molding device in which sprues are opened for each, and injects the first synthetic resin into the frame-shaped cavity at the forward position of the sliding core, and then injects the first synthetic resin into the bottom plate cavity at the retracted position of the sliding core. Molding of a multicolored resin container, characterized in that a second synthetic resin is injected into at least one of the interior and the top cavity, and a third synthetic resin is injected into the other to mold a synthetic resin container of at least two colors. Method. (2.) The first, second, and third synthetic resins are synthetic resins that have different colors and are compatible or fusible. The method for molding the described multicolored resin container. (3.) The sliding core includes a first sliding core that can move forward and backward into the container cavity, and a second sliding core that can slide into the lid cavity.
2. A method for molding a multicolor resin container according to claim 1, characterized in that said sliding cores are slidable together or separately from each other. (4.) The cavity type is provided with third and fourth sliding cores at positions facing the first and second sliding cores, respectively. The method for molding a multicolored resin container according to item 3.