JPS6139173B2 - - Google Patents

Description

Detailed Description of the Invention [Technical Field] The present invention provides a resin molded body with an exposed portion made of resin representing a plurality of characters, symbols, etc. in a different color from that of the resin molded body on the surface of the resin molded body. flush with the surface,
Or it relates to a multicolored resin molded body arranged to protrude from the surface of the resin molded body.

[Prior art] Until now, multiple characters,
A multicolored resin molded body is known in which a symbol or the like is projected and the projected portion is given a different color from the other portions.

Conventional multi-colored resin moldings have one exposed part that expresses characters, figures, etc. in a different color from the resin molding body, and one character, figure, etc. is independently formed in the resin molding body. Since it is embedded and only fixed to the resin molded body on the side and back surfaces of the thin exposed part, if the resin molded body is repeatedly bent during use, the exposed part and the resin molded body will be damaged. There was a problem in that the adhesion with the main body was broken and the exposed portion and the resin molded body were separated.

The present invention overcomes the above-mentioned problems, and even if the present invention has a large number of held members called exposed portions, the large number of held members can be inserted and fixed relatively easily and in a short time. It can be molded and produced with excellent workability and high productivity, and the produced resin molded products will not peel off from the exposed part and the resin molded body even after long-term use. The object of the present invention is to provide a multicolored resin molded article that does not separate.

[Means for Solving the Problems] That is, the multicolor resin molded article of the present invention has at least two exposed portions each having an exposed surface with one side in contact with the mold surface, and the exposed portions. It is composed of a first resin insert having a connecting part provided below the exposed surface to be connected, and a second resin main body that is insert-molded with the connecting part embedded, and the second resin body is embedded in the main body. The connecting portion and the insert are mechanically connected to the main body.

At the joint, the at least two joined resin held members are integrally molded by injection molding, compression molding, or the like. Note that the resin forming the held member may be either a thermoplastic resin or a thermosetting resin. It is undesirable for the joint portion to come out onto the mold surface where the member to be held is exposed during molding. Where possible, the joint is preferably embedded under a resin article of another color that is subsequently molded.

The method for molding the multicolored resin molded article of the present invention will be explained below.

As the mold used in the method for molding the multicolored resin molded article of the present invention, the same mold as conventional molds can be used. If it is necessary that the joint of the held member not be exposed on the back side of the molded multicolored resin, the mold surface forming the back side should have a pin that protrudes from the mold surface with a constant biasing force such as a spring. It is preferable to use molds. In this mold, the joint part of the held member is held in the center of the cavity with a pin, and in that state, resin of another color is filled,
The pin is pushed back into the mold by the molding pressure of the resin, the joint is securely held in the center of the cavity, and the pin is embedded in the resin after being injected into the cavity.
If the member to be held is made of the same type of thermoplastic resin as the resin of another color that will be injected later, the molten resin injected into the cavity may The joint of the holding member is heated, partially melts, and deforms with a small force. For this reason, it is preferable to use a mold that has a pin that holds the joint at the center of the cavity with the constant biasing force described above.

The first step of forming a mold for a multicolored resin molded body of the present invention is a step of fixing the member to be held integrally molded at the above-described joint portion to the above-described mold. In this process, the held member is integrated, so
There is no need to select one member to be held from a large number of members. For this reason, the first step is accomplished by a single operation of simply picking up the integrally held member, transporting it to the mold, and attaching it. Note that even when the individual members to be held are attached and fixed to the recesses of a plurality of molds, the individual members to be held are joined at the joint portion. Therefore, it becomes possible to integrally attach and fix the plurality of held members to the plurality of recesses.

The second step is a step of clamping the mold to which the member to be held is fixed, and filling and solidifying a resin having another color into the cavity. When the mold has a pin that presses the joint of the member to be held, the pin holds the joint in the center of the cavity with a constant biasing force by clamping the mold. In this state, molten resin of another color is injected into the cavity. Injection can be performed by injection molding or transfer molding. As the resin, thermoplastic resin, thermosetting resin, uncrosslinked rubber, etc. can be used. The resin injected into the cavity of the mold by injection pressure fills the cavity. At this time, the member to be held is partially embedded in the injected resin. Then, resins having other colors are solidified within the cavity by cooling solidification, crosslinking reaction, etc.

As a result, a multicolored resin molded article according to the present invention is molded. After this, the mold is opened and the multicolored resin molded body is taken out.

In this molding method, even when a large number of held members are exposed on the surface of the molded product,
Because each member to be held is connected at a joint,
This greatly facilitates the work when inserting the held member into each recess on the mold surface of the mold. moreover,
When the joint part of the held member is held in the center of the cavity by a pin that is biased with a constant biasing force while fixed to the mold, the joint part is exposed on the surface of the resulting molded product. Because this process does not require the use of plastic, it is possible to obtain multicolored resin molded products with high commercial value.

Examples will be described below.

First, a red-colored ethylene vinyl acetate copolymer resin was molded using the usual injection molding method to form a mold made of five letters T, U, R, B, and O, with a front view shown in Figure 1 and a cross section shown in Figure 2. The held member 1 was integrally injection molded. Each of the letters 11 to 15 constituting this held member 1 has a thickness of about 3 mm, a height of about 20 mm, and a width of about 25 mm, and each adjacent letter has a joint part 1.
6 was contacted. As shown in FIG. 2, each joint 16 is connected at each connecting portion on the back side of each character 11 to 15, and is a rod-shaped body having a thickness of 1 mm, a width of 1 mm, and an overlapping width of the connecting portions on the back side of 1 mm.

The mold used in this embodiment is a mold 2 for molding a mudguard for a passenger car, and FIG. 3 shows a partial sectional view of the mold with a member to be held inserted. The letters T, U, R, B, and O are formed as recesses 211 on the mold surface of one mold 21 of this mold 2. Pins 3 shown in FIG. 3 are formed on the mold surface of the other mold 22.
This pin 3 is made up of a round bar-shaped piston part 31 inserted into a cylindrical vertical hole 221 provided in the mold surface of the mold 22, and a spring 32 held between the bottom surface of the vertical hole 221 and the rear end surface of the piston part 21. It is configured. Each of the letters 11 to 15 of the member to be held 1 was inserted and fixed into each recess 211 of one mold 21 of this mold 2. Next, a J-shaped reinforcing metal serving as a mudguard reinforcement was inserted into this mold, and the mold was closed. When the mold is closed, the upper surface of the piston portion 31 of the pin 3 comes into contact with the back side of the joint portion 16 of the member to be held 1, and holds the joint portion 16 at the center of the cavity 2a. In this state, a black ethylene vinyl acetate copolymer resin made of the same resin as the member to be held 1 was injection molded to produce the mudguard shown in FIG. 4. This mudguard has T, U, R, B, red on the surface of the molded product.
O was exposed, and all other surfaces were molded from black resin. A cross section of this molded product is shown in FIG. The joint of the resin member to be held was partially melted and deformed by the heat during molding. However, the joint was not exposed on the surface of the mudguard.

[Effects of the Invention] In the multicolored resin molded article of the present invention, at least two exposed portions are connected by a connecting portion, and the connecting portion is embedded in the second resin body of the multicolored resin molded article. Therefore, even if the multicolored resin molded body encounters repeated bending and the adhesion of the exposed part eventually breaks down, the exposed part will still remain in the second resin body. This has the effect of ensuring that, even when producing the multicolored resin molded object, as in the past,
A large number of independent characters and symbols are made from resin to be held, and each one is selected according to the combination of characters, symbols, etc. that are to be expressed, and one by one is inserted into the recess of a predetermined mold and molded. There is also an effect that the work process of selecting the member to be held is unnecessary.

[Brief explanation of the drawing]

FIG. 1 shows a member to be held 1 used in an embodiment of the present invention.
Figure 2 is a front view of Figure 1.
The figure is a cross-sectional view of the main part of the mold 2 in which the held member 1 is fixed to the mold 2 and the mold is clamped, FIG. 4 is a perspective view of the molded product of this example, and FIG. - It is an arrow sectional view. DESCRIPTION OF SYMBOLS 1... Member to be held, 2... Molding die, 3... Pin, 16... Joint part.

Claims (1)

[Scope of Claims] 1. At least two exposed portions each having an exposed surface that is placed in contact with the mold surface, and a connecting portion provided below the exposed surface that connects the exposed portions. It is composed of a first resin insert and a second resin main body that is insert-molded with the connecting part embedded therein, and the connecting part embedded in the main body and the insert are mechanically attached to the main body. A multicolored resin molded body characterized by having a structure in which . 2. The multicolored resin molded article according to claim 1, wherein the exposed surface has a structure that protrudes from the surface of the main body.