JPH07117077A - In-mold transfer molding method and forming retaining mold - Google Patents

Abstract

PURPOSE:To form a boss or a pin by adapting an in-mold transfer molding method and a forming retaining mold and to enable the in-mold transfer to a surface having sudden unevenness. CONSTITUTION:A hole 17 is preliminarily provided to a transfer material 16 corresponding to the recessed part 14 of a retaining mold forming the protruding part of an injection molded product and the periphery of this hole is sucked from the suction port 15 of the retaining mold during injection and continuously fixed to the wall surface of a cavity to perform injection molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-mold transfer molding method and a mold, and more particularly to an in-mold transfer molding method for forming a pattern, for example, a circuit pattern, on the surface of an injection-molded article having bosses and pins. Regarding formwork.

[0002]

2. Description of the Related Art Conventionally, the following methods have been known as an in-mold transfer molding method for forming a pattern or circuit pattern on the surface of an injection molded product. As shown in FIG. 4, this in-mold transfer molding method involves inserting a transfer film 6 having a pattern and a circuit pattern 5 formed on a base film 4 on a parting surface of a mold 3 made up of a male mold 1 and a female mold 2. (FIG. 4 (1)) In this state, the synthetic resin 8 is injected into the cavity 7 of the mold 3 and injection molding is performed (FIG. 4 (2)) to mold the molded product 9 (FIG. 4 (3)). )). According to such an in-mold transfer molding method, the pattern or circuit pattern on the transfer film is transferred to the surface of the injection-molded product at the same time as the injection, and the pattern or the like is drawn on the surface without undergoing the painting process. Injection molded articles can be obtained.

In order to improve the basic in-mold transfer forming method as described above and accurately perform transfer with a mold having a deep cavity, in a method of sucking a heated transfer film into a female mold and injecting the film. Japanese Patent Laid-Open No. 3-124416 has been proposed in order to prevent the mark of the suction port from being left on the surface of the formed product.

[0004]

In the in-mold transfer injection molding method as described above, the transfer material is deformed by pressing the transfer material against the wall surface forming the molding space by the heat and pressure of the injected resin. Meanwhile, the pattern or circuit pan pattern printed on the transfer material is transferred to the molded product. For this reason, as described above, when a boss or a pin is formed on a molded product and an image or the like is transferred onto a surface having a sharp unevenness, the transfer material may be deformed by a large amount and may be damaged. . The transfer material thus damaged is caught in the resin and cannot be continuously molded. Further, in Japanese Patent Laid-Open No. 3-124416 described as a conventional technique, a suction port is provided at a position other than the cavity molding surface, and the mark of the suction port is not formed on the molded product. Also by the method, damage to the transfer material cannot be avoided when bosses and pins are similarly formed on the molded product and in-mold transfer is performed to a surface having a sharp unevenness. Therefore, the present invention is
An object of the present invention is to provide an in-mold transfer molding method and a forming frame that enable in-mold transfer to a surface having a boss or a pin and having a sharp unevenness.

[0005]

In the present invention, the first means for solving the above-mentioned problems relates to an in-mold transfer molding method, and as shown in FIG. , Positioned and placed between a mold frame composed of a male mold and a female mold forming a cavity, sucking a transfer material along the wall surface of the cavity, and joining the two molds together to form a resin inside the cavity. In the in-mold transfer molding method in which injection molding is performed and painting is performed at the same time as molding, holes are preliminarily formed in the transfer material in correspondence with the concave portions of the mold frame that form the convex portions of the injection molded product, and the periphery of this hole is formed. Is sucked during injection and is continuously fixed to the wall surface of the cavity.

A second means of the present invention relates to an in-mold transfer molding frame, in which a transfer material on which a pattern is printed is formed of a male mold forming a cavity and a female mold. For in-mold transfer molding, where it is positioned and positioned between the molds, suctions the transfer material along the wall surface of the cavity, joins the two molds, injects resin into the cavity, and paints at the same time as molding. In the mold, a suction port for sucking the periphery of the hole provided in the transfer material during injection injection is provided around the recess of the mold that forms the convex portion of the injection molded product.

[0007]

According to the present invention, the transfer material is preliminarily provided with a hole corresponding to the concave portion of the mold forming the convex portion of the injection-molded product, and the periphery of the hole is sucked from the suction port of the mold during injection injection. Then, since the injection molding is carried out while being continuously fixed to the cavity wall surface, the transfer material can be continuously molded without being deformed or damaged by the convex portion such as the boss of the injection-molded product.

[0008]

Embodiments of the in-mold transfer molding method according to the present invention will be described below with reference to the drawings. 1 to 3 show one embodiment of an in-mold transfer molding method using an in-mold transfer molding frame according to the present invention. In this embodiment, the injection-molded product 23 has a pattern 21 formed on one surface as shown in FIG. 3, and a pin 2 is formed on the surface on which the pattern 21 is drawn.
3a is to be formed. The mold is composed of a male mold 11 and a female mold 12. In the male mold 11, a nest 13 having a shape forming portion 14 of a pin 23a is inserted, and a suction port 15 is formed by a gap between the two 11 and 13. The female die 12 has a cavity concave portion 19 facing the male die 11 and a resin injection port 20.

A pattern 21 is formed on the transfer material 16, and
A hole 17 is formed at a position corresponding to the molding portion 14. Then, in order to perform injection molding using this mold, as shown in FIG.
First, the transfer material 17 is pressed against the male die 11 by the transfer material clamp 18 so as to follow the convex shape of the male die 11, as shown in FIG.

Further, the transfer material 16 is sucked from the suction port 15 arranged around the hole of the transfer material 16 and fixed to the male mold.
Further, as shown in FIG. 2, after joining the male mold and the female mold,
Resin is injected from the resin injection port 20.

The resin filled in the cavity space presses the transfer material 16 against the male mold 11 due to the internal pressure thereof, but in the pin-shaped molding portion 14, the transfer material 16 has holes 17 formed therein, and the transfer material 16 has a hole. There is no.

Therefore, the transfer material 16 is prevented from being rapidly deformed by the resin. On the other hand, the resin tries to enter between the transfer material 16 and the male mold 11 through the hole 17 of the transfer material 16 by its internal pressure, but since the transfer material is sucked by the male mold 11 at the position of the suction port 15, a gap is generated. Is sealed and resin cannot enter.

Then, with the mold opened, as shown in FIG. 3, a pin 23a is formed and a molded product 23 having a design 21 drawn is formed.

[0014]

As described above, according to the in-mold transfer molding method and the forming mold of the present invention, the transfer material is preliminarily applied to the transfer material corresponding to the concave portions of the mold forming the convex portions of the injection molded product. A hole is provided, and the periphery of this hole is sucked from the suction port of the mold during injection injection, and is continuously fixed to the cavity wall surface for injection molding. When performing the inner transfer molding, it is possible to prevent damage due to abrupt deformation of the transfer material and to prevent the transfer material from being caught in the resin, and it is possible to perform continuous molding.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an in-mold transfer molding method and a forming mold according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of an in-mold transfer molding method and a forming mold according to the present invention.

FIG. 3 is a cross-sectional view showing a molded product molded by the embodiment of the in-mold transfer molding method and the molding frame shown in FIGS. 1 and 2.

FIG. 4 is a cross-sectional view showing a conventional in-mold transfer molding method and a forming mold.

[Explanation of symbols]

 11 Male type 12 Female type 15 Suction port 16 Transfer material 17 Hole 21 Design

Claims (2)

[Claims] 1. A transfer material on which a pattern is printed is positioned and arranged between a mold frame which is composed of a male mold and a female mold for forming a cavity, and the transfer material is sucked to be along the wall surface of the cavity. In the in-mold transfer molding method in which both molds are joined, resin is injected and injected into the cavity, and painting is performed at the same time as molding, corresponding to the concave portion of the mold frame that forms the convex portion of the injection molded product. An in-mold transfer molding method characterized in that a hole is provided in advance in the transfer material, and the periphery of the hole is sucked during injection and injection and is continuously fixed to the cavity wall surface. 2. A transfer material on which a pattern is printed is positioned and arranged between a mold frame including a male mold forming a cavity and a female mold forming a cavity, and the transfer material is sucked to be along a wall surface of the cavity. , In the mold for in-mold transfer molding, in which the two molds are joined, resin is injected and injected into the cavity, and painting is performed at the same time as molding, in the concave part of the mold that forms the convex part of the injection molded product. A mold for in-mold transfer molding, wherein a suction port for sucking the periphery of the hole formed in the transfer material during injection injection is provided in the periphery.