JP2020199743A - Method for manufacturing resin molded product - Google Patents

Abstract

To provide a method for manufacturing a resin molded product, which allows easy and accurate positioning of a decorative sheet and can decorate a curved surface when insert molding is performed by using the decorative sheet.SOLUTION: There is provided a method for manufacturing a resin molded product that decorates one side of the resin molded product, the method comprises steps of: preparing a decorative sheet 1 having a decorative film 2 and a protective film 3 and having a through hole 31 formed therein; inserting a positioning protrusion 52 of a cavity 5 of a mold into the through hole of the decorative sheet to arrange the decorative sheet; combining the cavity and a core 6, which is the step of inserting a positioning protrusion into a positioning hole 62 of the core to fix the decorative sheet by sandwiching a holding portion 22 between the cavity and the core; injecting a resin into the mold to perform an insert molding; and taking out a resin molded product from the mold, in which surface decoration of the resin molded product is performed using a decoration portion 21 by peeling off the protective film.SELECTED DRAWING: Figure 5

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, if the shape of the decorative sheet is circular, there is a problem that positioning is difficult, 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 decorative film having a sandwiching portion located around the above and having a notch formed to separate the decorative portion from the sandwiching portion, and a protective film attached to the decorative surface of the decorative film. A step of preparing a decorative sheet having a plurality of positioning through holes that penetrate the sandwiching portion and the protective film, and arranging the decorative sheet in a mold having a cavity and a core. A plurality of positioning protrusions are provided on the contact surface of the cavity with the core so that the protective film comes into contact with the cavity in order to arrange the decorative sheet in the cavity. In the step of inserting the positioning protrusion into the through hole and the contact surface of the core with the cavity, a molding portion for molding the resin molded product and a plurality of positioning in which the plurality of positioning protrusions are inserted. A step of inserting a positioning protrusion of the cavity into the positioning hole of the core and fixing the decorative sheet by sandwiching the holding portion between the surface of the cavity and the surface of the core. The step of injecting resin into the mold to insert-mold the resin molded product and the step of removing the resin molded product from the mold are included, and by peeling off the protective film, the decorative portion is used. It is characterized in that the surface of the resin molded product is decorated.

A concave curved surface is provided in a portion of the cavity 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 the decorative portion. It is also possible.

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

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 formed to separate the decorative portion from the sandwiching portion, and being adhered to the decorative surface of the decorative film. A step of preparing a decorative sheet having a protective film and having a plurality of positioning through holes penetrating the sandwiching portion and the protective film, and the decorative sheet having a cavity and a core. It is arranged in a mold, and a molding portion for molding the resin molded product and a plurality of positioning protrusions are provided on the contact surface of the core with the cavity, and the decorative sheet is arranged in the core. Therefore, in the step of inserting the positioning protrusion into the through hole so that the decorative film comes into contact with the core, and on the contact surface of the cavity with the core, a plurality of the positioning protrusions are formed. A plurality of positioning holes to be inserted are provided, and the positioning protrusion of the core is inserted into the positioning hole of the cavity, and the holding portion of the decorative sheet is formed between the surface of the cavity and the surface of the core. The protective film is peeled off, including a step of sandwiching and fixing the resin molded product, a step of injecting resin into the mold to insert-mold the resin molded product, and a step of removing the resin molded product from the mold. The surface of the resin molded product is decorated by the decoration portion.

A concave curved surface is provided in a portion of the cavity 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 the decorative portion. It is also possible to do.

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 decorative film having a sandwiching portion located around the above and having a notch formed to separate the decorative portion from the sandwiching portion, and a protective film attached to the decorative surface of the decorative film. A step of preparing a decorative sheet having a plurality of positioning through holes that penetrate the sandwiching portion and the protective film, and arranging the decorative sheet in a mold having a cavity and a core. A plurality of positioning protrusions are provided on the contact surface of the cavity with the core so that the protective film comes into contact with the cavity in order to arrange the decorative sheet in the cavity. In the step of inserting the positioning protrusion into the through hole and the contact surface of the core with the cavity, a molding portion for molding the resin molded product and a plurality of positioning in which the plurality of positioning protrusions are inserted. A step of inserting a positioning protrusion of the cavity into the positioning hole of the core and fixing the decorative sheet by sandwiching the holding portion between the surface of the cavity and the surface of the core. The step of injecting resin into the mold to insert-mold the resin molded product and the step of removing the resin molded product from the mold are included, and by peeling off the protective film, the decorative portion is used. Since the surface of the resin molded product is in a decorated state, the decorative sheet can be easily and accurately positioned, and the surface of the resin molded product is misaligned. Alternatively, it is possible to decorate the decorative sheet neatly without causing wrinkles, and further, the adhesion and damage of chips and dust generated when the decorative sheet is cut to the surface of the decorative sheet are reduced. By improving the yield, it becomes possible to reduce the manufacturing cost of the decorated resin molded product.

Another 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 the resin molded product by insert molding using a decorative sheet. A decorative film having a sandwiching portion located around the decorative portion and having a notch formed to separate the decorative portion from the sandwiching portion, and being adhered to the decorative surface of the decorative film. A step of preparing a decorative sheet having a protective film and having a plurality of positioning through holes penetrating the sandwiching portion and the protective film, and the decorative sheet having a cavity and a core. It is arranged in a mold, and a molding portion for molding the resin molded product and a plurality of positioning protrusions are provided on the contact surface of the core with the cavity, and the decorative sheet is arranged in the core. Therefore, in the step of inserting the positioning protrusion into the through hole so that the decorative film comes into contact with the core, and on the contact surface of the cavity with the core, a plurality of the positioning protrusions are formed. A plurality of positioning holes to be inserted are provided, and the positioning protrusion of the core is inserted into the positioning hole of the cavity, and the holding portion of the decorative sheet is formed between the surface of the cavity and the surface of the core. The protective film is peeled off by including a step of sandwiching and fixing the resin, a step of injecting resin into the mold to insert-mold the resin molded product, and a step of removing the resin molded product from the mold. 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 resin molded product can be positioned easily and accurately. It is possible to decorate the surface 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 damage and improving yield, it becomes possible to reduce the manufacturing cost of the decorated resin molded product.

A concave curved surface is provided in a portion of the cavity 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 the decorative portion. This makes it possible to decorate the surface of the resin molded product without causing misalignment or wrinkles.

Even when the plane shape of the decorative portion of the decorative sheet is 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 and 2nd Embodiment. It is a perspective view after removing the decorative sheet from the resin molded article manufactured in 1st and 2nd 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 for producing 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 sandwiching portion 22 of the decorative film 2 is provided with two through holes 24 so as to sandwich the decorative portion 21.

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 protective film 3 is provided with two through holes 31 at the positions of the through holes 24 of the decorative film 2, and as shown in FIG. 2, the through holes 24 and the through holes 31 add the protective film 3. Holes penetrating the decorative sheet 1 are formed at two places, and the decorative sheet 1 is positioned with respect to the mold using the through holes 24 and 31. In the present embodiment, the through holes 24 and 31 are each two, but since they are used for positioning, at least two may be used, and three or more may be used.

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. A general adhesive film can be used as the protective film 3. 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 positioned on a surface that comes into contact with the core 6 when combined with the core 6, a decorative surface molding portion 51 that forms a decorative portion of the resin molded product 10, and two positioning portions. A protrusion 52 is provided. In the present embodiment, the decorative surface molding portion 51 has a circular planar shape in accordance with the planar shape (circular in the present embodiment) of the decorative portion of the resin molded product 10, and further, the resin. In order to make the decorative portion of the molded product 10 a convex curved surface, it has a concave curved surface.

As shown in FIG. 3, the two positioning protrusions 52 are arranged so as to sandwich the decorative surface forming portion 51 on the contact surface of the cavity 5 with the core 6. The positioning protrusion 52 is provided for positioning the decorative sheet 1, and is inserted into the through holes 24 and 31 of the decorative sheet 1 as shown in FIG. 5 (b). Therefore, the two positioning protrusions 52 are arranged at the same intervals as the through holes 24 and 31, and the through holes 24 and 31 can be inserted. After being inserted into the through holes 24 and 31, the addition is performed. The size is set so that the decorative sheet 1 does not shift.

It is also possible to provide a suction groove on the surface of the cavity 5 in order to securely hold the decorative sheet 1 when the through holes 24 and 31 of the decorative sheet 1 are inserted into the positioning protrusion 52. The suction groove can be arranged in an annular shape so as to surround the decorative surface molding portion 51, 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 is provided with a molding portion 61 for molding the resin molded product 10 on the contact surface with the cavity 5. An opening of the molding portion 61 is located on the contact surface of the cavity 5 with the core 6, and the shape of the opening is circular according to the planar shape of the resin molded product 10. Further, the core 6 is provided with two positioning holes 62 on the contact surface with the cavity 5 so as to sandwich the opening as shown in FIG. The positioning hole 62 is arranged so as to correspond to the two positioning protrusions 52, and is shown in FIGS. 5 (c) and 6 (a) when the cavity 5 and the core 6 are combined. As described above, the positioning protrusion 52 is inserted into the positioning hole 62 in a state where the decorative sheet 1 is positioned.

When the two positioning protrusions 52 of the cavity 5 are inserted into the two positioning holes 62 of the core 6 in order to combine the core 6 and the cavity 5, the surface of the core 6 becomes the surface of the cavity 5. At this time, as shown in FIG. 6A, the decorative sheet is abutted by sandwiching the portion of the holding portion 22 of the decorative sheet 1 between the surface of the core 6 and the surface of the cavity 5. 1 can be fixed at a predetermined position.

The mold is provided with a gate for injecting the 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.

Further, the decorative surface molding portion 51 of the cavity 5, the molding portion 61 of the core 6 and the like can be appropriately changed according to the shape of the resin molded product 10. The number of through holes 24 and 31 of the decorative sheet 1, the positioning protrusions 52 of the cavity 5, and the positioning holes 62 of the core 6 may be at least two and three or more. It is also possible, and the position is not limited to this embodiment, and can be changed as appropriate.

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 positioning protrusion 52 of the cavity 5 of the mold is provided. The decorative sheet 1 is inserted into the through holes 24 and 31 of the decorative sheet 1 and the decorative sheet 1 is arranged on the surface of the cavity 5.

The decorative sheet 1 is arranged on the surface of the cavity 5 so that the protective film 3 is on the cavity 5 side. At this time, the decorative sheet 1 is held by the positioning protrusion 52. As shown in FIG. 5B, the decorative portion 21 of the decorative film 2 of the decorative sheet 1 accurately overlaps with the decorative surface forming portion 51 of the cavity 5 due to the positioning. It is arranged like this.

As described above, by providing the decorative sheet 1 with the two through holes 24 and 31 and providing the cavity 5 with the two positioning protrusions 52, the positioning protrusions 52 are inserted into the through holes 24 and 31. The decorative sheet 1 can be accurately arranged at a predetermined position by a simple operation of arranging the decorative sheet 1 in the cavity 5, and the decorative portion 21 is the decorative surface forming portion 51. It will be in a state where it exactly overlaps with. At this time, if the suction groove is provided on the surface of the cavity 5, the decorative sheet 1 can be more reliably held.

After arranging the decorative sheet 1 in the cavity 5, the core 6 and the cavity 5 are combined to assemble the mold, as shown in FIGS. 5 (c) and 6 (a). The positioning protrusion 52 of the cavity 5 is inserted into the positioning hole 62 of the core 6. When the positioning protrusion 52 is inserted into the positioning hole 62, as shown in FIG. 6A, the surface of the core 6 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 surface of the cavity 5 and the surface of the core 6, and the decorative sheet 1 is fixed.

At this time, the decorative surface molding portion 51 provided on the surface of the cavity 5 overlaps with the opening of the molding portion 61 of the core 6 via the decoration portion 21 of the decoration sheet 1 and the protective film 3. However, since the decorative surface forming portion 51 has a concave curved surface, it is in contact with the decorative sheet 1 as shown in the cross-sectional view of FIG. 6A. However, there is a gap between the decorative surface forming portion 51 and the protective film 3 of the decorative sheet 1. When the decorative surface forming portion 51 is flat, such a gap does not occur.

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

After the decorative sheet 1 is fixed in the mold in this way, the resin is injected into the molding portion 61 of the mold through a gate, and the resin molded product 10 is insert-molded. The resin injected from the gate into the mold is injected into the molding portion 61, and the decorative portion 21 of the decorative film 2 of the decorative sheet 1 is molded into the decorative surface molding portion 51 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 cavity 5 is positioned from the through holes 24 and 31 of the decorative sheet 1 as shown in FIG. 7A. While pulling out the protrusion 52, the core 6 is removed from the cavity 5 to open the surface of the mold, and then, as shown in FIG. 7B, the resin molded product 10 is taken out from the core 6. .. 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, the protective film 3 and the holding portion 22 of the decorative film 2 are removed, and as shown in FIG. 9, the surface is covered with the decorative sheet 1. The resin molded product 10 in a state in which the decorative portion 21 is integrally molded and decorated 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.

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, and further, the above-mentioned Since the process after molding the resin molded product 10 is simply to remove the decorative sheet 1, the protective film 3 protects the decorative portion 21 before and during resin molding to improve the yield. By doing so, it has 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 molding portion 71 for molding the resin molded product 10, and an opening of the molding portion 71 is located on a surface in contact with the cavity 8. The shape of the opening is the same as the flat shape (circular in the present embodiment) of the decorative portion of the resin molded product 10.

Further, the core 7 is provided with two positioning protrusions 72 on the contact surface with the cavity 8 so as to sandwich the opening as shown in FIG. The positioning protrusion 72 is provided for positioning the decorative sheet 1, and is inserted into the through holes 24 and 31 of the decorative sheet 1 as shown in FIG. 12 (b). Therefore, the two positioning protrusions 72 are arranged at the same intervals as the through holes 24 and 31, and the through holes 24 and 31 can be inserted. After being inserted into the through holes 24 and 31, the addition is performed. The size is set so that the decorative sheet 1 does not shift.

When the cavity 8 is combined with the core 7, the decorative surface molding portion 81 and two positioning holes 82 are provided on the contact surface with the core 7, as shown in FIG. As shown in FIG. 13A, the decorative surface forming portion 81 is provided at a position overlapping the opening of the forming portion 71 when the cavity 8 is combined with the core 7, and the forming portion 71 is provided. It has a surface shape for closing the opening of the resin molded product 10 and molding the decorative portion of the resin molded product 10. In the present embodiment, the decorative surface molding portion 81 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. ..

As shown in FIG. 11, the two positioning holes 82 are arranged so as to sandwich the decorative surface forming portion 81 on the contact surface of the cavity 8 with the core 7, and the two positioning holes 82 are positioned. Corresponding to the protrusion 72, when the core 7 and the cavity 8 are combined, the positioning protrusion 72 is the decorative sheet 1 as shown in FIGS. 12 (c) and 13 (a). Is inserted into the positioning hole 82 in a positioned state.

It is also possible to provide a suction groove on the surface of the core 7 in order to securely hold the decorative sheet 1 when the through holes 24 and 31 of the decorative sheet 1 are inserted into the positioning protrusion 72. The suction groove can be arranged in an annular shape so as to surround the molded portion 71, for example, until the core 7 and the cavity 8 are combined by sucking the decorative sheet 1 by the suction groove. During that time, the protective sheet 1 can be reliably held.

When the two positioning protrusions 72 of the core 7 are inserted into the positioning holes 82 of the cavity 8 in order to combine the cavity 8 and the core 7, the surface of the cavity 8 comes into contact with the surface of the core 7. At this time, as shown in FIG. 13A, the decorative sheet 1 is sandwiched between the surface of the cavity 8 and the surface of the core 7 by sandwiching the portion of the holding portion 22 of the decorative sheet 1. It can be fixed in a predetermined position.

The mold is provided with a gate for injecting a resin required for sheet insert molding, but is not shown and detailed description thereof is omitted. The mold can be changed to various shapes and structures according to the shape of the resin molded product 10. Further, the shape of the molded portion 71 of the core 7, the shape of the cavity 8, and the shape of the decorative surface molded portion 81 can be appropriately changed according to the shape of the resin molded product 10. The number of through holes 24 and 31 of the decorative sheet 1, the positioning protrusions 72 of the core 7, and the positioning holes 82 of the cavity 8 may be at least two and three or more. It is also possible, and the position is not limited to this embodiment, and can be changed as appropriate.

A method for producing a resin molded product according to a second embodiment of the present invention will be described. Similar to the first embodiment, the method for producing the resin molded product of the second embodiment is a manufacturing method in which the resin molded product 10 which is a lid is insert-molded and the surface of the resin molded product 10 is decorated. .. 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 positioning protrusion 72 of the core 7 of the mold is provided. The decorative sheet 1 is inserted into the through holes 24 and 31 of the decorative sheet 1 and the decorative sheet 1 is arranged on the surface of the core 7.

The decorative sheet 1 is arranged on the surface of the core 7 so that the decorative film 2 is on the core 7 side. At this time, the decorative sheet 1 is formed by the positioning protrusion 72. By being held and positioned, as shown in FIG. 12B, the decorative portion 21 of the decorative film 2 of the decorative sheet 1 exactly overlaps the opening of the molded portion 71 of the core 7. It is arranged like this.

In this way, by providing the decorative sheet 1 with two through holes 24 and 31 and providing the core 7 with two positioning protrusions 72, the positioning protrusions 72 are inserted into the through holes 24 and 31. In addition, the decorative sheet 1 can be accurately arranged at a predetermined position by a simple operation of arranging the decorative sheet 1 on the core 7, and the decorative portion 21 is formed on the molded portion 71. It can be exactly overlapped with the opening. At this time, if the suction groove is provided on the surface of the core 7, the decorative sheet 1 can be more reliably held.

After arranging the decorative sheet 1 in the core 7, the cavity 8 and the core 7 are combined to assemble the mold, as shown in FIGS. 12 (c) and 13 (a). The positioning protrusion 72 of the core 7 is inserted into the positioning hole 82 of the cavity 8. When the positioning protrusion 72 is inserted into the positioning hole 82, as shown in FIG. 13A, the surface of the cavity 8 comes into contact with the protective film 3 of the decorative sheet 1, and the decorative sheet 1 The portion of the sandwiching portion 22 is sandwiched between the surface of the core 7 and the surface of the cavity 8, and the decorative sheet 1 is fixed.

At this time, the decorative surface molding portion 81 provided on the surface of the cavity 8 overlaps with the opening of the molding portion 71 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 81 has a concave curved surface, it is in contact with the decorative sheet 1 as shown in the cross-sectional view of FIG. 13 (a). However, there is a gap between the decorative surface forming portion 81 and the protective film 3 of the decorative sheet 1. When the decorative surface forming portion 81 is flat, such a gap does not occur.

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

After the decorative sheet 1 is fixed in the mold in this way, resin is injected into the molding portion 71 of the mold through a gate, and the resin molded product 10 is insert-molded. The resin injected from the gate into the mold is injected into the molding portion 71, and the decorative portion 21 of the decorative film 2 of the decorative sheet 1 is molded into the decorative surface molding portion 81 of the cavity 8. As shown in FIG. 13B, the decorative portion of the resin molded product 10 is molded.

At this time, only the decorative portion 21 separated from the sandwiching portion 22 by the notch 23 is deformed according to the shape of the decorative portion of the resin molded product 10 by the injected resin, and at the same time, the protective film. In No. 3, since the portion to which the decorative portion 21 is attached is similarly deformed, even if the curved surface is decorated, wrinkles and the like are less likely to occur on the decorative film 2, and a beautiful finish is realized. It works.

Further, in the method for producing a resin molded product of the present invention, the surface of the decorative portion 21 of the decorative film 2 is adhered to the protective film 3, so that the surface of the decorative portion 21 is formed during injection molding. It has an excellent effect that the resin can be prevented from wrapping around the resin, and the decorative portion 21 can be prevented from being moved by the injected resin to cause a misalignment.

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 core 7 while removing the positioning protrusion 72 of the core 7 from the through holes 24 and 31 of the protective sheet 1. 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 when the decorative sheet 1 is no longer needed, the protective film 3 and the holding portion 22 of the decorative film 2 are removed. As shown in FIG. 9, the resin molded product 10 in a state in which the decorative portion 21 is integrally molded and decorated on the surface 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.

Since the decorative portion 21 is separated by the notch 23, the decorative portion 21 can be easily added by simply pulling the decorative sheet 1 while leaving the decorative portion 21 on the surface of the resin molded product 10. The decorative sheet 1 can be removed.

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. The decorative film 2 can be protected by the protective film 3 even before the decorative sheet 1 is used, and the decorative film 2 is protected by the protective film 3 even during resin molding. Further, since it is possible to protect the decorative portion 21 with the protective film 3 even after resin molding, the decorative portion 21 which is the decorative surface of the resin molded product 10 is protected throughout the entire process. It has an excellent effect of being able to do it.

1 Decorative sheet 2 Decorative film 21 Decorative part 22 Holding part 23 Notch 24 Through hole 3 Protective film 31 Through hole 5, 8 Cavity 51, 81 Decorative surface molding part 52, 72 Positioning protrusion 6, 7 Core 61, 71 Molded part 62, 82 Positioning hole 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 sandwiching portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and a decorative film of the decorative film. A step of preparing a decorative sheet having a protective film attached to a surface and having a plurality of through holes for positioning that penetrate the sandwiching portion and the protective film.
The decorative sheet is arranged in a mold having a cavity and a core, and a plurality of positioning protrusions are provided on the contact surface of the cavity with the core, and the decorative sheet is arranged in the cavity. Therefore, a step of inserting the positioning protrusion into the through hole so that the protective film comes into contact with the cavity, and
A molding portion for molding the resin molded product and a plurality of positioning holes into which the plurality of positioning protrusions are inserted are provided on the contact surface of the core with the cavity, and the positioning protrusions of the cavity are provided. Is inserted into the positioning hole of the core, and the sandwiching portion of the decorative sheet is sandwiched and fixed between the surface of the cavity and the surface of the core.
The process of injecting resin into the mold and insert molding the resin molded product,
Including the step of removing the resin molded product from the mold.
A method for producing a resin molded product, which comprises peeling off the protective film to decorate the surface of the resin molded product by the decorative portion. A concave curved surface is provided in a portion of the cavity 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 the decorative portion. The method for producing a resin molded product according to claim 1, wherein the resin molded product is produced. 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 sandwiching portion located around the decorative portion and having a notch for separating the decorative portion and the sandwiching portion, and a decorative film of the decorative film. A step of preparing a decorative sheet having a protective film attached to a surface and having a plurality of through holes for positioning that penetrate the sandwiching portion and the protective film.
The decorative sheet is arranged in a mold having a cavity and a core, and a molding portion for molding the resin molded product and a plurality of positioning protrusions are provided on the contact surface of the core with the cavity. In order to dispose the decorative sheet in the core, a step of inserting the positioning protrusion into the through hole so that the decorative film comes into contact with the core.
A plurality of positioning holes into which the plurality of positioning protrusions are inserted are provided on the contact surface of the cavity with the core, and the positioning protrusions of the core are inserted into the positioning holes of the cavity. A step of sandwiching and fixing the holding portion of the decorative sheet between the surface of the cavity and the surface of the core.
The process of injecting resin into the mold and insert molding the resin molded product,
Including the step of removing the resin molded product from the mold.
A method for producing a resin molded product, which comprises peeling off the protective film to decorate the surface of the resin molded product by the decorative portion. A concave curved surface is provided in a portion of the cavity 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 the decorative portion. The method for producing a resin molded product according to claim 4, wherein the resin molded product is manufactured. 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.