JP2020185745A - Manufacturing method for resin molded products - Google Patents

Abstract

To provide a method for manufacturing a resin molded product that allows easy and accurate positioning of a decoration sheet and decoration of a curved surface when insert molding with a decoration sheet.SOLUTION: A method for manufacturing a resin molded product 10 for decorating one side of a resin molded product includes the step of preparing a decorated sheet 1 having a decorated film 2 and a protective film 3, the step of arranging the decorated sheet in a mold having a cavity 5 and a core 6, and arranging the decorated sheet in a sandwiching portion 22 in a concave portion 51 of the cavity, the step of combining the cavity with the core, inserting the convex portion 61 of the core into the concave portion and fixing the sandwiching portion of the decorated sheet between the concave portion and the convex portion, the step of injecting resin into the mold for insert molding, and the step of removing the resin molded product from the mold. The decorating of the surface of the resin molded product is performed by the decorating portion by peeling the protective film.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for producing a resin molded product that decorates one surface of the resin molded product by insert molding using a decorative sheet.

Two types of molding methods, in-mold molding and insert molding, are mainly used as a method of decorating a resin molded product at the same time by using a decorative film. In in-mold molding, a roll-shaped decorative film is sandwiched between molds, and resin is injected and injection-molded to transfer the resin to the surface of the molded product (see Patent Document 1). In in-mold molding, the decorative film protruding from the resin molded product becomes foil burrs, so a step of removing the foil burrs is required, and the roll-shaped decorative film is sandwiched between the molds, resulting in misalignment. There is a problem.

Insert molding is a method in which a decorative sheet cut into a predetermined shape is placed in a mold, and resin is injected into the mold to form the decorative sheet, thereby integrating the decorative sheet on the surface of the resin molded product. Yes (see Patent Document 2). Compared to in-mold molding, insert molding does not have the problem of foil burrs and is less likely to cause misalignment, but chips and dust generated when cutting the decorative sheet are generated. Adhesion, there is a problem that positioning is difficult if the shape of the decorative sheet is circular, there is also a problem that resin flows between the decorative sheet and the mold, or the decorative sheet shifts, especially on curved surfaces It was difficult to decorate.

Japanese Unexamined Patent Publication No. 2014-172196 Japanese Unexamined Patent Publication No. 2013-184294

The present invention makes it easy and accurate to position the decorative sheet when insert molding using the decorative sheet, prevents adhesion and damage of dust and the like to the surface of the decorative sheet during manufacturing, and further, resin. It is an object of the present invention to provide a method for manufacturing a resin molded product capable of decorating a curved surface of the resin molded product by preventing misalignment of the decorative sheet when the resin is injected.

The method for producing a resin molded product of the present invention is a method for producing a resin molded product that decorates one surface of a resin molded product by insert molding using a decorative sheet, and is a method for producing a decorative portion and the decorative portion. A decoration having a holding portion located around the above, and a notch forming a notch for separating the decoration portion and the holding portion, and a protective film attached to the decorative surface of the decoration film. The step of preparing the sheet, the decorative sheet is arranged in a mold having a cavity and a core, the cavity is provided with a recess, and a holding portion for holding the decorative sheet is provided in the recess. The decorative sheet is arranged in the holding portion so that the protective film is on the inside, and the core is provided with a convex portion to be inserted into the concave portion, and the convex portion is provided. Is provided with a molding portion for molding a resin molded product, the convex portion is inserted into the concave portion, and the holding portion of the decorative sheet is sandwiched between the holding portion of the cavity and the convex portion of the core. A step of injecting resin into the mold to insert-mold the resin molded product, and a step of taking out the resin molded product from the mold are included, and the protective film is peeled off to obtain the above-mentioned. It is characterized in that the surface of the resin molded product is decorated by the decoration portion.

The holding portion of the cavity is provided with a concave curved surface in a portion corresponding to the decorative portion, the surface of the resin molded product is formed into a convex curved surface, and the surface of the curved surface of the resin molded product is decorated. It is also possible to decorate by the part.

The planar shape of the decorative portion of the decorative sheet can be circular or oval.

Another method of manufacturing the resin molded product of the present invention is a method of manufacturing a resin molded product that decorates one surface of the resin molded product by insert molding using a decorative sheet, and the decorative portion and the decorative portion. A decorative film having a sandwiching portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and a protective film attached to the decorative surface of the decorative film. A step of preparing a decorative sheet having the above, a molding portion for arranging the decorative sheet in a mold having a core and a cavity, a recess is provided in the core, and a molding portion for molding the resin molded product in the recess. A holding portion for holding the decorative sheet is provided, and the step of arranging the decorative sheet in the holding portion so that the protective film is on the outside and the cavity being inserted into the recess. The convex portion is provided, and the convex portion is inserted into the concave portion, and the holding portion of the core and the convex portion of the cavity sandwich and fix the holding portion of the decorative sheet. A step of injecting resin into a mold to insert-mold a resin molded product and a step of taking out the resin molded product from the mold are included. By peeling off the protective film, the resin molding is performed by the decorative portion. The feature is that the surface of the product is decorated.

The core holding portion is provided with a concave curved surface at a portion corresponding to the decorative portion, the surface of the resin molded product is formed with a convex curved surface, and the surface of the curved surface of the resin molded product is the decorative portion. It is also possible to decorate with.

The planar shape of the decorative portion of the decorative sheet can be circular or oval.

The method for producing a resin molded product of the present invention is a method for producing a resin molded product that decorates one surface of a resin molded product by insert molding using a decorative sheet, and is a method for producing a decorative portion and the decorative portion. A decoration having a holding portion located around the above, and a notch forming a notch for separating the decoration portion and the holding portion, and a protective film attached to the decorative surface of the decoration film. The step of preparing the sheet, the decorative sheet is arranged in a mold having a cavity and a core, the cavity is provided with a recess, and a holding portion for holding the decorative sheet is provided in the recess. The decorative sheet is arranged in the holding portion so that the protective film is on the inside, and the core is provided with a convex portion to be inserted into the concave portion, and the convex portion is provided. Is provided with a molding portion for molding a resin molded product, the convex portion is inserted into the concave portion, and the holding portion of the decorative sheet is sandwiched between the holding portion of the cavity and the convex portion of the core. A step of injecting resin into the mold to insert-mold the resin molded product, and a step of taking out the resin molded product from the mold are included, and the protective film is peeled off to obtain the above-mentioned. Since the surface of the resin molded product is decorated by the decorative portion, the decorative sheet can be easily and accurately positioned, and the surface of the resin molded product can be easily and accurately positioned. In addition, it is possible to decorate the decorative sheet neatly without causing misalignment or wrinkles, and further, adhesion of chips and dust generated when the decorative sheet is cut to the surface of the decorative sheet and By reducing the damage and improving the yield, it becomes possible to reduce the manufacturing cost of the decorated resin molded product.

The holding portion of the cavity is provided with a concave curved surface in a portion corresponding to the decorative portion, the surface of the resin molded product is formed into a convex curved surface, and the surface of the curved surface of the resin molded product is decorated. By decorating the resin molded product by the portion, it is possible to decorate the surface of the resin molded product without causing misalignment or wrinkles.

Another form of manufacturing method of the resin molded product of the present invention is a method for manufacturing a resin molded product that decorates one surface of the resin molded product by insert molding using a decorative sheet, and is a method of manufacturing the resin molded product together with the decorative portion. A decorative film having a sandwiching portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and a protective film attached to the decorative surface of the decorative film. The step of preparing a decorative sheet having the above, the decorative sheet is placed in a mold having a core and a cavity, a recess is provided in the core, and a molding portion for molding the resin molded product in the recess and a molding portion. A holding portion for holding the decorative sheet is provided, and the step of arranging the decorative sheet in the holding portion so that the protective film is on the outside and the cavity being inserted into the recess. The convex portion is provided, and the convex portion is inserted into the concave portion, and the holding portion of the core and the convex portion of the cavity sandwich and fix the holding portion of the decorative sheet. A step of injecting resin into a mold to insert-mold a resin molded product and a step of taking out the resin molded product from the mold are included, and by peeling off the protective film, the resin molding is performed by the decorative portion. Since the surface of the product is decorated, the decorative sheet can be easily and accurately positioned, and the surface of the resin molded product is misaligned or misaligned. It is possible to decorate beautifully without causing wrinkles, and the yield is reduced by reducing the adhesion and damage of chips and dust generated when cutting the decorative sheet to the surface of the decorative sheet. By improving, it becomes possible to reduce the manufacturing cost of the decorated resin molded product.

The core holding portion is provided with a concave curved surface in a portion corresponding to the decorative portion, the surface of the resin molded product is formed into a convex curved surface, and the surface of the curved surface of the resin molded product is decorated. By decorating the resin molded product by the portion, it is possible to decorate the surface of the resin molded product without causing misalignment or wrinkles.

By making the plane shape of the decorative portion of the decorative sheet circular or elliptical, it is possible to prevent the decorative sheet from shifting and further facilitate the positioning of the decorative sheet.

It is a perspective view of the decorative sheet used in the manufacturing method of the resin molded article of 1st Embodiment of this invention. It is sectional drawing of the decorative sheet used in 1st Embodiment. It is a perspective view of the cavity used in 1st Embodiment. It is a perspective view of the core used in 1st Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 1st Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 1st Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 1st Embodiment. It is a perspective view before removing the decorative sheet from the resin molded article manufactured in 1st Embodiment. It is a perspective view after removing the decorative sheet from the resin molded article manufactured in 1st Embodiment. It is a perspective view of the core used in 2nd Embodiment. It is a perspective view of the cavity used in 2nd Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 2nd Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 2nd Embodiment. It is sectional drawing which shows the process of the manufacturing method of the resin molded article of 2nd Embodiment.

The method for producing the resin molded product of the present invention will be described in detail below with reference to the drawings. First, the method for producing the resin molded product according to the first embodiment of the present invention will be described, but the decorative sheet 1 used in the first embodiment will be described first. FIG. 1 is a perspective view of a decorative sheet 1 used in the method for producing a resin molded product according to the first embodiment of the present invention, and FIG. 2 is a sectional view. The method of manufacturing the resin molded product of the first embodiment will be described using a circular lid as the resin molded product 10, and a case where the surface of the lid is decorated will be described. The use, shape, and place to decorate the resin molded product are not particularly limited, and the present invention can be applied to resin molded products of various uses and shapes, and the surface to be decorated can be used. , If it is one side of a resin molded product, it is not limited to the surface.

The decorative sheet 1 used in the method for producing the resin molded product of the first embodiment is a sheet for decorating the surface of the lid, which is the resin molded product 10, and is decorated as shown in FIG. It is composed of a film 2 and a protective film 3. As shown in FIG. 1, the decorative film 2 is a circular decorative portion 21 that matches the decorative portion of the resin molded product 10, and a holding portion that is located around the decorative portion 21 and has a rectangular outline. It is composed of 22, and the decorative portion 21 and the sandwiching portion 22 are separated by an annular notch 23.

The decorative film 2 is a film having a decorative surface which is decorated by printing or the like on one surface, and it is sufficient that at least only the decorative portion 21 is decorated, and in some cases, the decorative film 2. The sandwiching portion 22 may also be decorated. The shape of the decorative portion 21 is not limited to a circular shape, and may be any shape that matches the decorative portion of the resin molded product 10, and may be an elliptical shape. can do. Further, the decoration method of the decoration portion 21 is not limited, and various conventional means can be used.

The notch 23 is a line obtained by cutting the decorative film 2 in accordance with the shape of the decorative portion of the resin molded product 10, and by providing the notch 23 in the decorative film 2, the resin is formed. After molding the molded product 10, the decorative sheet 1 can be easily removed from the resin molded product 10 with the decorative portion 21 left on the surface of the resin molded product 10.

One side of the protective film 3 is an adhesive surface, and the decorative film 2 is attached to the adhesive surface. The adhesive strength of the protective film 3 is such that the decorative film 2 can be held, the resin molded product 10 is molded, and then the decorative sheet 1 can be removed while the decorative portion 21 remains. As the protective film 3, a general adhesive film can be used. As the protective film 3, for example, a polyethylene-based film having an adhesive surface provided on one surface can be used, but the material is not particularly limited, and various films can be used, and transparent or translucent. , Or it may be opaque. If the surface of the resin molded product is not flat, the protective film 3 needs to be deformed during injection molding. In this case, it is preferable to use a material that is easily deformed.

By adhering the protective film 3 to the decorative surface of the decorative film 2, the decorative sheet 1 can protect the decorative surface until the molding of the resin molded product 10 is completed. It is possible to prevent problems such as dust adhering to the surface of the decorative film 2 and damage to the surface. It is possible to improve the yield due to defects in the decorative film that occur in the conventional manufacturing process, and it is possible to reduce the manufacturing cost.

Next, the mold used in the method for producing the resin molded product of the first embodiment will be described. The mold is composed of a cavity 5 and a core 6. As shown in FIG. 3, the cavity 5 is provided with a recess 51 for inserting and arranging the decorative sheet 1. Since the recess 51 is provided for inserting the decorative sheet 1 and arranging it at a predetermined position with respect to the cavity 5, it has the same planar shape as the decorative sheet 1. The recess 51 is provided with a holding portion 52 for holding the decorative sheet 1 and a decorative surface molding portion 53 for molding the decorative portion of the resin molded product 10. The decorative surface molding portion 53 has a circular planar shape, and is further formed on a concave curved surface in order to make the decorative portion of the resin molded product 10 a convex curved surface. The flat surface around the decorative surface forming portion 53 is the holding portion 52.

It is also possible to provide a suction groove in the portion of the holding portion 52 in order to securely hold the decorative sheet 1 when the decorative sheet 1 is inserted into the recess 51. The suction groove can be arranged in an annular shape so as to surround the decorative surface molding portion 53, for example, and the cavity 5 and the core 6 are sucked by the suction groove to suck the decorative sheet 1. It is possible to reliably hold the protective sheet 1 until it is combined.

As shown in FIG. 4, the core 6 has a convex portion 61 that is inserted into the concave portion 51 of the cavity 5 when the core 6 is combined with the cavity 5. The convex portion 61 has a shape of being fitted into the concave portion 51, and as shown in FIG. 4, a molding portion for molding the resin molded product 10 is formed on the surface of the tip of the convex portion 61. 62 is provided, and a flat holding portion 63 is provided around the opening of the molded portion 62. The shape of the opening of the molded portion 62 is a planar shape (circular in this embodiment) of the decorative portion of the resin molded product 10.

When the convex portion 61 of the core 6 is inserted into the concave portion 51 of the cavity 5 in order to combine the core 6 with the cavity 5, the holding portion 63 of the core 6 comes into contact with the holding portion 52 of the cavity 5. At that time, as shown in FIG. 6B, the decorative sheet 1 is placed at a predetermined position by sandwiching the portion of the holding portion 22 of the decorative sheet 1 between the holding portion 63 and the holding portion 52. Can be fixed.

The mold is provided with a gate for injecting a resin required for sheet insert molding, and various structures of the conventional mold are used for the conventional structure required for such injection molding. Therefore, it is not shown and detailed explanation is omitted. Various patterns can be formed on the mold by changing it to various shapes and structures according to the shape of the resin molded product 10 or by performing processing such as engraving.

The planar shape of the concave portion 51 of the cavity 5 and the convex portion 61 of the core 6 is rectangular in the present embodiment, but is not particularly limited and can be changed according to the shape of the resin molded product. is there. However, since positioning needs to be performed by inserting the decorative sheet 1 into the recess 51, the shape may be any shape as long as the decorative sheet 1 can be positioned, and it is not preferable to make it circular.

The shape of the decorative surface molding portion 53 at the tip of the concave portion 51 can be changed according to the shape of the surface of the decorative portion of the resin molded product 10, and only the concave curved surface as in the present embodiment is used. However, a convex curved surface or the like is also possible, and any shape may be used as long as the decorative sheet 1 can follow and deform during injection molding.

A method for producing a resin molded product according to the first embodiment of the present invention will be described. In the method for producing a resin molded product of the first embodiment, the resin molded product 10 which is a lid is insert-molded using the decorative sheet 1 and the mold, and the surface of the resin molded product 10 is decorated. It is a manufacturing method. The decorative sheet 1 decorated with a predetermined design as shown in FIG. 1 is prepared, and as shown in FIGS. 5A and 5B, the decoration sheet 1 is inserted into the recess 51 of the cavity 5 of the mold. The decorative sheet 1 is inserted, and the decorative sheet 1 is arranged on the surface of the holding portion 52 in the recess 51.

The decorative sheet 1 is inserted into the recess 51 with the protective film 3 on the inside and in contact with the holding portion 52 of the cavity 5. When the decorative sheet 1 is inserted into the recess 51 and arranged so as to come into contact with the holding portion 52, as shown in FIG. 5B, the decorative portion 21 of the decorative film 2 of the decorative sheet 1 becomes , Is arranged so as to overlap the decorative surface forming portion 53 of the cavity 5. At this time, since the planar shape of the concave portion 51 of the mold is the same as the planar shape of the decorative sheet 1, the orientation of the decorative sheet 1 is confirmed and the decorative sheet 1 is simply inserted into the concave portion 51. The decorative sheet 1 can be accurately arranged at a predetermined position, and the decorative portion 21 is in a state of accurately overlapping the decorative surface forming portion 53. At this time, if the suction groove is provided in the holding portion 52, it is possible to maintain the state in which the decorative sheet 1 is held more reliably.

After inserting the decorative sheet 1 into the recess 51, the core 6 is combined with the cavity 5 to assemble the mold, as shown in FIGS. 5 (c) and 6 (a). The convex portion 61 of 6 is inserted into the concave portion 51 of the cavity 5. When the convex portion 61 is inserted into the concave portion 51, as shown in FIG. 6A, the tip of the convex portion 61 comes into contact with the decorative film 2 of the decorative sheet 1 and the decorative sheet 1 The portion of the sandwiching portion 22 is sandwiched between the holding portion 52 of the cavity 5 and the holding portion 63 of the core 6, and the decorative sheet 1 is fixed.

At this time, the decorative surface forming portion 53 provided in the concave portion 51 of the cavity 5 passes through the protective film 3 of the decorative sheet 1 and the decorative portion 21 to form the forming portion 62 of the core 6. Although it is located so as to overlap the opening of the above, the decorative surface forming portion 53 has a concave curved surface, so that the decorative surface forming portion 53 and the decorative sheet 1 are as shown in the cross-sectional view of FIG. 6A. Are not in contact with each other, and a gap is formed between the decorative surface forming portion 53 and the protective film 3 of the decorative sheet 1. When the decorative surface forming portion 53 is flat, such a gap does not occur.

In this way, the cavity 5 and the core 6 are combined to assemble the mold, and the holding portion 22 of the decorative sheet 1 is sandwiched between the holding portion 52 of the cavity 5 and the holding portion 63 of the core 6. When the cavity 5 and the core 6 are fixed to each other in this state, the decorative sheet 1 is firmly fixed in a state of being accurately positioned at a predetermined position in the mold.

After fixing the decorative sheet 1 in the mold in this way, resin is injected into the molding portion 62 of the mold through a gate, and the resin molded product 10 is injection-molded. The resin injected from the gate into the mold is injected into the molding portion 62, and the decorative portion 21 of the decorative film 2 of the decorative sheet 1 is molded into the decorative surface molding portion 53 of the cavity 5. As shown in FIG. 6B, the decorative portion of the resin molded product 10 is molded.

At this time, since the decorative portion 21 is separated from the sandwiching portion 22 by the notch 23, only the decorative portion 21 of the decorative film 2 is the decorative portion of the resin molded product 10. With respect to the protective film 3 to which the decorative portion 21 is attached, the portion to which the decorative portion 21 is attached is elastically deformed. As described above, in the method for producing the resin molded product of the present invention, since the decorative portion 21 of the decorative film 2 is separated from the sandwiching portion 22 by the notch 23, the sandwiching portion 22 is fixed. Since only the decorative portion 21 can be deformed in this state, there is an effect that wrinkles and the like are less likely to occur on the decorative film 2 when the curved surface is decorated.

Further, in the method for producing a resin molded product of the present embodiment, the surface of the decorative portion 21 of the decorative film 2 is protected by the protective film 3, so that the decorative portion 21 can be formed during injection molding. It is possible to prevent the resin from wrapping around the surface, and it is possible to achieve the effect that the decorative surface of the resin molded product 10 can be beautifully finished. Further, since the decorative portion 21 is attached to the protective film 3, it is possible to prevent the decorative portion 21 from being pushed by the resin and moving to cause misalignment.

When the injection of the resin into the mold is completed and the molding of the resin molded product 10 is completed, the core 6 is removed from the cavity 5 to open the surface of the mold as shown in FIG. 7A. Then, as shown in FIG. 7B, the resin molded product 10 is taken out from the cavity 5. When the resin molded product 10 is taken out, as shown in FIG. 8, the decorative sheet 1 is in a state of being attached to the resin molded product 10.

When the decorative sheet 1 is removed from the resin molded product 10 in such a state, as shown in FIG. 9, the decorative portion 21 is integrally molded and added to the surface of the resin molded product 10. The resin molded product 10 in the decorated state is completed. As shown in FIG. 9, the decorative sheet 1 removed from the resin molded product 10 is in a state in which the decorative portion 21 has been removed.

When the decorative sheet 1 is removed, the decorative portion 21 is separated by the notch 23. Therefore, simply by pulling the decorative sheet 1 or pulling the resin molded product 10, the decorative portion 21 is pulled. The 21 can be easily removed from the resin molded product 10 while leaving the 21 on the surface of the resin molded product 10. Since the edge of the decorative portion 21 on the surface of the resin molded product 10 is in a state of being neatly cut, as compared with the conventional technique of cutting the decorative film after resin molding, the above The accuracy and aesthetics of the decorative portion of the resin molded product 10 are improved, and the step of cutting the decorative film after resin molding becomes unnecessary, which leads to a reduction in manufacturing cost.

The timing of removing the decorative sheet 1 from the resin molded product 10 does not have to be immediately after the resin molded product 10 is removed from the mold, and the resin molding is performed until the step of eliminating the decorative sheet 1. It is also possible to use the decorative sheet 1 as a protective sheet for protecting the decorative portion of the resin molded product 10 without removing the decorative sheet 1 from the product 10.

The method for producing a resin molded product of the present invention has an excellent effect that decoration can be performed more easily and accurately than before by using the decoration sheet 1 and the mold. Since the process after molding the resin molded product 10 is only to remove the decorative sheet 1, the conventional process of cutting the decorative sheet becomes unnecessary, and the protective film 3 makes it possible to perform before resin molding and the resin. By protecting the decorative portion 21 during molding, the yield is improved, which is an excellent effect that the manufacturing cost can be reduced.

Next, a method for producing the resin molded product of the second embodiment will be described. Since the decorative sheet 1 used in the second embodiment is the same as that in the first embodiment, the description of the decorative sheet 1 is omitted, and the method for manufacturing the resin molded product of the second embodiment is omitted. The mold used for is described. The mold is composed of a core 7 and a cavity 8. As shown in FIG. 10, the core 7 is provided with a recess 71 for inserting and arranging the decorative sheet 1, and a molding portion 72 for molding the resin molded product 10 in the recess 71. , And a holding portion 73 is provided.

Since the recess 71 is provided for inserting the decorative sheet 1 and arranging it at a predetermined position with respect to the core 7, it has the same planar shape as the decorative sheet 1. The opening of the molded portion 72 is located in the recess 71, and the shape of the opening is a planar shape (circular in the present embodiment) of the decorative portion of the resin molded product 10. In the recess 71, the holding portion 73 is provided around the opening. In order to reliably hold the decorative sheet 1 inserted into the recess 71, it is also possible to provide a suction groove in the portion of the holding portion 73. For example, by sucking the decorative sheet 1 by the suction grooves arranged in an annular shape so as to surround the opening of the molding portion 72, the protective sheet is surely used until the core 7 and the cavity 8 are combined. It becomes possible to hold 1.

As shown in FIG. 11, the cavity 8 has a convex portion 81 that is inserted into the concave portion 71 of the core 7 when the cavity 8 is combined with the core 7. The convex portion 81 has a shape of being fitted into the concave portion 71, and as shown in FIG. 11, a holding portion that abuts the holding portion 73 of the core 7 on the surface of the tip of the convex portion 81. A decorative surface molding portion 83 is formed which closes the openings of the molding portion 72 and the molding portion 72 and forms the decorative portion of the resin molded product 10. The decorative surface molding portion 83 has a circular planar shape, and is further formed on a concave curved surface in order to make the decorative portion of the resin molded product 10 a convex curved surface.

When the convex portion 81 of the cavity 8 is inserted into the concave portion 71 of the core 7 in order to combine the cavity 8 with the core 7, the holding portion 82 of the cavity 8 comes into contact with the holding portion 73 of the core 7. At that time, as shown in FIG. 13B, the decorative sheet 1 is held at a predetermined position by sandwiching the portion of the holding portion 22 of the decorative sheet 1 between the holding portion 82 and the holding portion 73. Can be fixed.

The mold is provided with a gate for injecting a resin required for sheet insert molding, and various structures of the conventional mold are used for the conventional structure required for such injection molding. Therefore, it is not shown and detailed description is omitted. The mold can be changed to various shapes and structures according to the shape of the resin molded product 10.

The planar shape of the concave portion 71 of the core 7 and the convex portion 81 of the cavity 8 is rectangular in the present embodiment, but is not particularly limited and can be changed according to the shape of the resin molded product. is there. However, since positioning needs to be performed by inserting the decorative sheet 1 into the recess 71, the shape may be any shape as long as the decorative sheet 1 can be positioned, and it is not preferable to make it circular.

The shape of the decorative surface molding portion 83 at the tip of the convex portion 81 can be changed according to the shape of the surface of the decorative portion of the resin molded product 10, and only the concave curved surface as in the present embodiment can be changed. However, a convex curved surface or the like is also possible, and it can be a curved shape within a range in which the decorative sheet 1 can follow and deform during injection molding, or another shape.

A method for producing a resin molded product according to a second embodiment of the present invention will be described. In the method for producing a resin molded product of the second embodiment, similarly to the first embodiment, the resin molded product 10 as a lid is insert-molded using the decorative sheet 1 and the mold, and the resin is formed. This is a manufacturing method for decorating the surface of the molded product 10. The decorative sheet 1 decorated with a predetermined design as shown in FIG. 1 is prepared, and as shown in FIGS. 12 (a) and 12 (b), the decorative sheet 1 is inserted into the recess 71 of the core 7 of the mold. The decorative sheet 1 is inserted, and the decorative sheet 1 is arranged on the surface of the holding portion 73 of the recess 71.

The decorative sheet 1 is inserted into the recess 71 so that the protective film 3 is on the outside and the decorative film 2 is in contact with the holding portion 73 of the core 7. When the decorative sheet 1 is inserted into the recess 71 and arranged, as shown in FIG. 12B, the decorative portion 21 of the decorative film 2 of the decorative sheet 1 is formed on the molded portion 72 of the core 7. Arranged so as to overlap the opening. At this time, since the planar shape of the concave portion 71 of the mold and the planar shape of the decorative sheet 1 are the same, it is only necessary to confirm the orientation of the decorative sheet 1 and insert it into the concave portion 71. The decorative sheet 1 can be accurately arranged at a predetermined position, and the decorative portion 21 is in a state of accurately overlapping the opening of the molded portion 72.

After inserting the decorative sheet 1 into the recess 71, the cavity 8 is combined with the core 7 to assemble the mold, as shown in FIGS. 12 (c) and 13 (a). The convex portion 81 of 8 is inserted into the concave portion 71 of the core 7. When the convex portion 81 is inserted into the concave portion 71, as shown in FIG. 13A, the tip of the convex portion 81 comes into contact with the protective film 3 of the decorative sheet 1 and sandwiches the decorative sheet 1. The portion of the portion 22 is sandwiched between the holding portion 73 of the core 7 and the holding portion 82 of the cavity 8, and the decorative sheet 1 is fixed.

At this time, the decorative surface molding portion 83 provided at the tip of the convex portion 81 opens the molding portion 72 of the core 7 via the decoration portion 21 of the decoration sheet 1 and the protective film 3. However, since the decorative surface forming portion 83 has a concave curved surface, as shown in the cross-sectional view of FIG. 13A, the decorative surface forming portion 83 is in contact with the decorative sheet 1. It is not in contact with each other, and a gap is formed between the decorative surface forming portion 83 and the protective film 3 of the decorative sheet 1. When the decorative surface forming portion 83 is flat, such a gap does not occur.

In this way, the core 7 and the cavity 8 are combined to assemble the mold, and the holding portion 22 of the decorative sheet 1 is sandwiched between the holding portion 73 of the core 7 and the holding portion 82 of the cavity 8. When the core 7 and the cavity 8 are fixed to each other in this state, the decorative sheet 1 is firmly fixed in a state of being accurately positioned at a predetermined position in the mold.

After fixing the decorative sheet 1 in the mold in this way, resin is injected into the molding portion 72 of the mold through a gate, and the resin molded product 10 is injection-molded. The resin injected from the gate into the mold is injected into the molding portion 72, and the decorative portion 21 of the decorative film 2 of the decorative sheet 1 is molded into the decorative surface molding portion 83 of the cavity 8. As shown in FIG. 13B, the decorative portion of the resin molded product 10 is molded.

At this time, the decorative portion 21 is separated from the sandwiching portion 22 by the notch 23, so that the method for producing a resin molded product of the present invention is the decorative film when a curved surface is decorated. It has the effect of preventing wrinkles from occurring in 2. Further, in the method for producing a resin molded product of the present invention, the decorative film 2 of the decorative sheet 1 is protected by the protective film 3, so that the resin is applied to the surface of the decorative portion 21 during injection molding. It has the effect of preventing the resin molded product 10 from wrapping around and finishing the decorative surface of the resin molded product 10 neatly, and further prevents the decorative portion 21 from being pushed by the resin and moving to cause misalignment. It has the effect of being able to do it.

When the injection of the resin into the mold is completed and the molding of the resin molded product 10 is completed, the cavity 8 is removed from the core 7 to open the surface of the mold as shown in FIG. 14A. Then, as shown in FIG. 14B, the resin molded product 10 is taken out from the recess 71 of the core 7. When the resin molded product 10 is taken out, as shown in FIG. 8, the decorative sheet 1 is in a state of being attached to the resin molded product 10.

After that, as in the first embodiment, when the decorative sheet 1 is removed from the resin molded product 10, the decorative portion 21 is integrally molded on the surface as shown in FIG. The resin molded product 10 in the decorated state is completed. As shown in FIG. 9, the decorative sheet 1 removed from the resin molded product 10 is in a state in which the decorative portion 21 has been removed.

When the decorative sheet 1 is removed, the protective film 3 and the decorative film 2 can be obtained by simply pulling the decorative sheet 1 or the resin molded product 10 by providing the notch 23. The sandwiching portion 22 can be easily and neatly removed from the resin molded product 10.

The timing for removing the decorative sheet 1 from the resin molded product 10 may be various timings such as immediately after the resin molded product 10 is removed from the mold, or a step in which the decorative sheet 1 becomes unnecessary. it can.

1 Decorative sheet 2 Decorative film 21 Decorative part 22 Holding part 23 Notch 3 Protective film 5,8 Cavity 51,71 Recessed part 52,73 Holding part 53,83 Decorative surface molded part 6,7 Core 61,81 Convex part 62,72 Molded part 63,82 Holding part 10,10'Resin molded product

Claims (6)

It is a method for manufacturing a resin molded product that decorates one surface of the resin molded product by insert molding using a decorative sheet.
A decorative film having a decorative portion and a holding portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and adhering to the decorative surface of the decorative film. The process of preparing a decorative sheet with a protective film
The decorative sheet is arranged in a mold having a cavity and a core, the cavity is provided with a recess, and a holding portion for holding the decorative sheet is provided in the recess, and the decorative sheet is provided. In the step of arranging the protective film on the holding portion so as to be inside.
The core is provided with a convex portion to be inserted into the concave portion, and the convex portion is provided with a molding portion for molding a resin molded product. The convex portion is inserted into the concave portion, and the convex portion is inserted. A step of sandwiching and fixing the holding portion of the decorative sheet between the holding portion of the cavity and the convex portion of the core, and
The process of injecting resin into the mold and insert molding the resin molded product,
Including the step of taking out the resin molded product from the mold.
A method for producing a resin molded product, characterized in that the surface of the resin molded product is decorated by the decorative portion by peeling off the protective film. The holding portion of the cavity is provided with a concave curved surface in a portion corresponding to the decorative portion, the surface of the resin molded product is formed into a convex curved surface, and the surface of the curved surface of the resin molded product is the decorative portion. The method for producing a resin molded product according to claim 1, wherein the resin molded product is decorated with. The method for producing a resin molded product according to claim 1 or 2, wherein the planar shape of the decorative portion of the decorative sheet is circular or elliptical. It is a method for manufacturing a resin molded product that decorates one surface of the resin molded product by insert molding using a decorative sheet.
A decorative film having a decorative portion and a holding portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and adhering to the decorative surface of the decorative film. The process of preparing a decorative sheet with a protective film
The decorative sheet is arranged in a mold having a core and a cavity, the core is provided with a recess, and a molding portion for molding the resin molded product and a holding portion for holding the decorative sheet are provided in the recess. The step of arranging the decorative sheet on the holding portion so that the protective film is on the outside.
The cavity is provided with a convex portion to be inserted into the concave portion, the convex portion is inserted into the concave portion, and the decorative sheet is sandwiched between the holding portion of the core and the convex portion of the cavity. The process of sandwiching and fixing the part and
The process of injecting resin into the mold and insert molding the resin molded product,
Including the step of taking out the resin molded product from the mold.
A method for producing a resin molded product, characterized in that the surface of the resin molded product is decorated by the decorative portion by peeling off the protective film. The core holding portion is provided with a concave curved surface at a portion corresponding to the decorative portion, the surface of the resin molded product is formed with a convex curved surface, and the surface of the curved surface of the resin molded product is the decorative portion. The method for producing a resin molded product according to claim 4, wherein the resin molded product is decorated with. The method for producing a resin molded product according to claim 4 or 5, wherein the planar shape of the decorative portion of the decorative sheet is circular or elliptical.