JPS63251212A - Method for in-mold printing and molding - Google Patents

Abstract

PURPOSE:To prevent the surface of a molded item from the occurrence of wrinkles, by providing gas exhausting holes in a film when the film having a transfer image is inserted in a mold and the image is transferred on the surface of the molded item by pouring and molding a molten resin. CONSTITUTION:An image holding member 6 is prepared by fixing patterns 6b, 6c... to be transferred on a rolled resin film of continuous length. Holes 12a, 12b and 12c are perforated on a recessed part or a punched part 8d for inserting a different member on a molded item 8. This perforation is carried out at a proper time when the image holding member 6 is prepared or when the image holding member is inserted in the mold. After the film 6 is passed through between a fixed mold and a movable mold, and the image 6b on the film 6 is set at a specific position in a cavity, a molten resin is poured in the cavity from an injection cylinder and the image on the film is thereby transferred on the poured resin surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a molding method in which a holding member for holding a transferred image is inserted into a mold and the image is transferred to a molded article made of injected resin.

In particular, the present invention relates to a molding method including a method for removing gas such as gas or air existing between the holding member and the mold member.

[Prior art]

As mentioned above, in the molding method in which the image holding member is inserted into the cavity and the image of the image holding member is transferred onto the surface of the injected resin, the gas, air, etc. Exhaust air was being emitted from gaps.

[Problem of the invention and means for achieving the problem]

As shown in FIGS. 5A and 5B, an image holding film 6 holding a transferred image is fixed in the cavity 4 of a mold consisting of a fixed mold 1 and a moving mold 2, and is passed through a sprue 1a to an injection cylinder (not shown). The resin material is injected into the cavity from the film 6.
When the image on the film is transferred to the resin surface while pressing it against the inner surface of the mold, the air in the space surrounded by the sliding mold 2 and the film 6 shown in section B in Figure 5 is released to the outside through the parting lines P and L. Although it is exhausted,
Some of the air is not completely exhausted until the end of the resin injection, and the remaining air causes distortion in the film 6, resulting in wrinkles in the image on the film, and therefore wrinkles in the transferred image of the molded product. remains on the molded product.

The purpose of the present invention is to provide a molding method that does not cause wrinkles in the transferred image of a molded product, and also allows degassing in response to the pressure when the film holding the transferred image is pressed against the inner surface of the mold by a resin material. As it is done, the image on the transfer film will be accurately wrinkled and distorted.

We propose a molding method that can transfer images without causing sagging.

In order to achieve the above-mentioned problems, the present invention has been made as shown in FIG.
In this method, the above-mentioned problem is solved by providing a gas vent hole on the film 6 to vent the gas between the film 6 and the cavity surface 2a when the film material 6 is pressed against the cavity surface 2a of the sliding mold 2 by injection of resin material. This is what I did.

[Explanation of Examples]

FIG. 1 shows an image holding member 6 according to the present invention, and the image holding member 6 fixes images 6b, 6C, . . . to be transferred onto a roll-shaped resin film 6a having a long radius by printing or the like.

In Fig. 1, the images 6b, 6c, etc. are placed on the upper royal road for convenience of molding two pieces at the same time.

FIG. 2 shows a front view of a molded article 8 in which the image 6b is transferred to the molded article by the molding method according to the present invention.

The molded product 8 is a resin material with the image 6b on the film 6a transferred onto the lid member of a cassette box of an 8 mm video camera, and when it is molded without using the degassing described later, wrinkles appear in the IOA as shown in the figure. , IOB occurs. 8a A, B, C, and D on the molded product are, for example, the product name or trademark, 8b is the border of the design mark, 8
c is a transparent portion, and 8d is a recessed portion or punched portion for fitting a different member.

Figure 3 shows an example in which a gas vent hole is provided in the image holding member.
In this example, a hole 1 is formed in the above-mentioned recess or punched part 8d of the molded product 8.
Drill holes 2a, t2b, and 12c.

The perforation is performed at an appropriate time such as when the image holding member 6 is manufactured, when printing the image, or when inserting the image holding member into a mold.

4A, B, C, and D show the molding and transfer process, in which the film 6 is passed between the fixed mold and the melting mold when the mold can be opened, and the image 6b on the film 6 is placed in a predetermined position in the cavity. Set it so that it is in the correct position.

Thereafter, the mold is closed as shown in FIG.

When molten resin is injected into the cavity from an injection cylinder (not shown) through the sprue 1a, the film tube 6 is pressed toward the cavity surface 2a due to the amount of movement.

With this suppressed movement of the film, the gas between the film 6 and the cavity surface 28 escapes to the opposite side of the film 6 through the gas vent holes 12a, 12b, 12c and reaches the parting line, as shown in FIG. 4B. The gas is exhausted to the outside of the mold through the mold gap and the fitting gap of an ejector turbine (not shown). The film pressed by the resin due to the exhaust of gas is pressed against the cavity inner surface 2a by filling the cavity with molten resin without causing distortion (fourth
Figure C), at the same time the image on the film is transferred to the injected resin surface.

In the present invention, gas venting holes 12a + 12b
, l 2 c is a different part fitting part 8d of the molded product 8
hole 12 on the transfer image surface of film 6.
In a, 12b, and 12c, the presence of the chain type is obvious immediately after molding, but after a different member (not shown) as a cassette cover lid member is fixed to the recess or punched portion, the existence of the chain type becomes obvious.

[Effects] The present invention provides a film with a transferred image on the surface of the molded product by inserting the film with the transferred image into a mold and transferring the image to the surface of the molded product by injection molding of molten resin. It was possible to suppress the occurrence of wrinkles on the surface.

If the molded product has a notch 8e shown in Fig. 2 or a real part with a complicated shape, the tensile action of the resin injected into the film or the insertion of the mold member into the complex-shaped space, such as in the mold parts 1 and 3, may occur during molding. Due to the resin going around, the film was often distorted and wrinkled, and the wrinkles tended to become larger.However, according to the present invention, gas can be effectively vented from the complex-shaped space mentioned above, and wrinkles can be eliminated. We were able to suppress the outbreak.

[Brief explanation of drawings]

Figures 1 and 3 are a plan view of an image holding member printed with an image to be transferred used in the present invention, Figure 2 is a front view of a molded product, and Figures 4A, 4B, and 4C are FIG. 5A and FIG. 5B are explanatory diagrams of conventional image transfer. l...Fixed type available 2...Electric type available 2...aJ moving mold cavity surface 6...Image holding member (film) 6b/6c...Image to be transferred 8...Molded product 10A・IOB...wrinkles

Claims (2)

[Claims] (1) An image holding member holding a transferred image is inserted into the cavity of a mold consisting of a movable mold and a fixed mold, a gas venting hole is formed in the image holding member, and after the mold is closed, a molding resin material is injected. The image holding member is pressed against one of the mold members by the injected resin to transfer the transferred image of the image holding member onto the surface of the injected resin, and the gas between the image holding member and the mold is released through the gas vent hole. An in-mold printing molding method characterized by: (2) The molded product formed from the injected resin has a recess or a punched portion, and the gas vent hole is formed in an image holding member printed on the recess or the punched portion. The in-mold printing molding method according to item 1.