JP2010221515A - Mold for in-mold coating - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold for in-mold coating capable of ensuring a space through which a coating material for performing in-mold coating flows. <P>SOLUTION: The mold for in-mold coating includes an undercut-shaped recess 15 formed of a wall portion 15a provided in a mold opening direction and an inclined wall portion 15b provided to face the wall portion 15a at a predetermined angle α2 in a region corresponding to an end or a corner portion of a product. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an in-mold coating mold for performing an in-mold coating method.

2. Description of the Related Art Conventionally, it is a mold for taking a large number of pieces, and a runner is connected to each of a plurality of cavities, and a recess is formed on a surface other than a surface through which a covering material flows among surfaces forming the runner. A mold is known (see, for example, Patent Document 1). By forming such a recess, solidification of the molten resin in the recess is delayed, and the tensile force with respect to the resin molded product molded in the cavity can be suppressed. In addition, since the tensile force with respect to the resin molded product molded in the cavity is suppressed, the resin molded product standing surface portion molded at the standing surface portion of the cavity is not deformed due to condensation accompanying the molding.

JP 2006-289794 A

However, in the technique described in Patent Document 1, it is considered that there is an effect on the contraction in the longitudinal direction, but it cannot cope with the contraction (vertical direction) of the standing surface itself, and as a result, the corner of the resin molded product There is a problem that the portion is in close contact with the cavity and a filling failure of the covering material occurs.

  The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a mold that can secure a space for flowing a coating material for performing in-mold coating. It is intended to provide a mold for inner coating.

In order to solve the above-described problems, the present invention provides a mold for in-mold coating, which has a wall portion provided in the mold opening direction at a portion corresponding to an end portion or a corner portion of the product, and a predetermined angle while facing the wall portion. An undercut concave portion formed by an inclined wall portion provided to be provided is provided.

In addition, it is desirable that an angle α2 formed between the wall portion and the inclined wall portion is equal to or greater than an angle β2 formed between the wall portion and the product surface of the vertical wall (α2 ≧ β2).

ADVANTAGE OF THE INVENTION According to this invention, even if it is a complicated product shape, the shrinkage | contraction of a resin product can be directed to a desired direction, and the clearance gap which a coating material flows between a resin product and a cavity can be ensured. By ensuring the gap through which the covering material flows, the covering material can be filled, and a sufficient film thickness can be obtained on the surface of the resin product.

If the angle α2 is set to an appropriate angle, a gap through which the covering material flows can be reliably formed between the resin product and the cavity.

It is explanatory drawing of a resin product, (a) is a perspective view, (b) is the sectional view on the AA line of FIG. (A), (c) is sectional drawing of the state which gave the coating | covering material Outline illustration of the in-mold coating method Enlarged view of anchor Enlarged view of the main parts of resin products Action diagram It is explanatory drawing of the metal mold | die for in-mold | coating which concerns on this invention, (a) is sectional drawing, (b) is principal part expanded sectional drawing. Sectional drawing of the product molded with the in-mold coating mold according to the present invention

  Embodiments of the present invention will be described below with reference to the accompanying drawings. It is assumed that the resin product 1 to be applied with in-mold coating has a box shape and a concave shape at the center as shown in FIG. As shown in FIG. 1B, the resin product 1 from the cross section of the resin product 1 has an end 1a, a vertical wall 1b, a corner 1c, a horizontal wall 1d, a corner 1e, a vertical wall 1f, a corner. It has a portion 1g, a horizontal wall portion 1h, a corner portion 1i, a vertical wall portion 1j, a corner portion 1k, a horizontal wall portion 1l, a corner portion 1m, a vertical wall portion 1n, and an end portion 1o. And as shown in FIG.1 (c), the coating | coated material 3 is coated on the surface 2 of the resin product 1. As shown in FIG.

In order to carry out the in-mold coating for such a resin product 1, as shown in FIG. 2, a gap through which the covering material 3 flows between the surface 2 of the injection-molded resin product 1 and the cavity 4 is provided. 5 must be formed. Therefore, a substantially rectangular parallelepiped anchor portion 7 connected to the end portion 1a, the corner portion 1g, the corner portion 1i, and the end portion 1o of the resin product 1 in contact with the core 6 is formed on the core 6 side.

As shown in FIG. 3, the anchor portion 7 is surrounded by a wall portion 7a provided in the mold opening direction, an inclined wall portion 7b facing the wall portion 7a and having a predetermined angle α1, a bottom surface 7c, and the like. Molded. The anchor portion 7 is formed to have a larger bottom surface 7c than a surface 7d connected to the end portions 1a, 1o and the corner portions 1g, 1i, and has an undercut shape only on the inclined wall portion 7b side.

As shown in FIG. 4, the angle α1 formed by the wall portion 7a and the inclined wall portion 7b is equal to or greater than the angle β1 formed by the wall portion 7a and the product surface 2 of the vertical wall portion 1j (α1 ≧ β1). It is desirable. The same applies to the angle β1 formed between the wall portion 7a and the product surface 2 of the other vertical wall portions 1b, 1f, and 1n.

By providing the anchor portion 7 at the end portions 1a and 1o and the corner portions 1g and 1i of the resin product 1, the resin 10 can be restrained against contraction in the direction of arrow A as shown in FIG. Restraint force can also be obtained against deformation of the resin 10 due to shrinkage in the B direction.

Furthermore, since the anchor portion 7 has an undercut shape, the behavior of the resin 10 toward the cavity 4 when the resin 10 contracts can be suppressed, so that the gap 5 through which the covering material 3 flows can be secured. . In addition, the behavior of the resin 10 toward the cavity 4 can be suppressed by the inclined surface of the inclined wall portion 7b even at a site where there is contraction in the biaxial direction, and the gap 5 is secured.

In order to form such an anchor portion 7, the in-mold coating mold according to the present invention is formed on the end portions 1a, 1o or the corner portions 1g, 1i of the resin product 1, as shown in FIG. An undercut-shaped concave portion 15 formed by a wall portion 15a provided in the mold opening direction from the core 6 side and an inclined wall portion 15b provided to face the wall portion 15a and having a predetermined angle α2 is provided at a corresponding portion. The core 6 was provided.

The angle α2 formed by the wall 15a and the inclined wall 15b is equal to or greater than the angle β2 formed by the wall 15a and the product surface 2 of the vertical wall 1j as shown in FIG. 6B ( α2 ≧ β2) is desirable. The same applies to the angle β2 formed between the wall portion 15a and the product surface 2 of the other vertical wall portions 1b, 1f, and 1n.

The undercut anchor portion 7 is formed by the undercut recess 15. A gap 5 through which the covering material 3 flows is formed between the surface 2 of the injection-molded resin product 1 and the cavity 4 by the action of the anchor portion 7 described above. Further, the coating material 3 is supplied to the gap 5 and the surface 2 of the resin product 1 is coated with the coating material 3.

The resin product 1 whose surface 2 is coated with the covering material 3 is taken out from the mold, even if the undercut-shaped anchor portion 7 is formed as a part of the resin product 1, the wall portion 15a and the inclined wall portion 15b. By setting the formed angle α2 to an appropriate value, smooth operation is performed. And as shown in FIG. 7, the product which coated the coating | covering material 3 on the surface 2 of the resin product 1 is produced.

According to the present invention, an in-mold coating mold that can be filled with a coating material by ensuring a gap through which the coating material flows between the resin product and the cavity, and can obtain a sufficient film thickness on the surface of the resin product. Can be provided.

DESCRIPTION OF SYMBOLS 1 ... Resin product, 1a, 1o ... End part, 1b, 1f, 1j, 1n ... Vertical wall part, 1c, 1e, 1g, 1i, 1k, 1m ... Corner part, 1d, 1h, 1l ... Horizontal wall part, 2 ... Surface, 3 ... Covering material, 4 ... Cavity, 5 ... Gap, 6 ... Core, 7 ... Anchor part, 7a ... Wall part, 7b ... Inclined wall part, 10 ... Resin, 15 ... Recessed part, 15a ... Wall part, 15b ... Inclined wall.

Claims (2)

In the mold for in-mold coating, it is formed with a wall portion provided in the mold opening direction at a portion corresponding to the end portion or corner portion of the product and an inclined wall portion provided opposite to the wall portion and provided with a predetermined angle. A mold for in-mold coating, which is provided with an undercut concave portion. 2. The mold for in-mold coating according to claim 1, wherein an angle α2 formed between the wall portion and the inclined wall portion is equal to or greater than an angle β2 formed between the wall portion and a product surface of the vertical wall ( A mold for in-mold coating characterized by α2 ≧ β2).