JP7779138B2 - Manufacturing method for insert molding - Google Patents

Description

This disclosure relates to a method for manufacturing an insert molded product and the insert molded product.

Conventionally, insert-molded products comprising a sheet material and a base resin layer formed on the back surface of the sheet material have been used, for example, as decorative parts. Deterioration of insert-molded products can cause problems, such as peeling of the sheet material from the base resin layer or, if the sheet material has a laminated structure, interfacial peeling between layers. Peeling often begins at the edge of the sheet material. For example, Patent Document 1 discloses a technology that prevents edge peeling by forming a fixing part made of molded resin to cover the edge of the insert film.

Japanese Patent Application Laid-Open No. 2018-94813

However, with the technology of Patent Document 1, the cavity shape for forming the fixing portion is not simple, and there are problems with the number of manufacturing steps and costs.

This disclosure therefore provides a simple configuration to more reliably prevent peeling of the sheet material at the edges of an insert-molded product, thereby improving the durability of the insert-molded product.

In order to solve the above problems, one embodiment of a manufacturing method of an insert molded product disclosed herein includes:
A method for manufacturing an insert-molded product including a sheet material and a base resin layer formed on a back surface of the sheet material,
an end processing step of continuously forming at least one of a concave-convex cutout portion and a plurality of openings in the end portion of the sheet material along the edge of the end portion;
a placement step of placing the sheet material in a mold;
an injection step of injecting a base resin, which is a raw material for the base resin layer, onto the back surface side of the sheet material,
the forming die has a step portion that is convex or concave toward the sheet material at a position facing at least one of the notch portion and the opening portion at an end of the sheet material when the sheet material is placed in the forming die,
a gap is formed between a part of an edge of the sheet material and the molding die by the step portion when the sheet material is placed in the molding die,
In the injection step, the base resin is injected into the gap through at least one of the notch and the opening ,
The above-mentioned mold is
a cavity mold in which the sheet material is placed;
a core mold that is closed with the cavity mold at their mating surfaces to form a cavity into which the base resin is injected,
the step portion is formed by an end portion of the mating surface of the core mold on the cavity side protruding toward the cavity side or receding in a direction away from the cavity side relative to an end portion of the mating surface of the cavity mold on the cavity side when the cavity mold and the core mold are closed together,
In the placing step, the sheet material is placed in the cavity mold so that the surface of the sheet material contacts the surface of the cavity mold and a part of the edge side of at least one of the notch portion and the opening portion protrudes from the end portion of the cavity mold toward the core mold.
It is characterized by:

In insert-molded products that include a sheet material and a base resin layer formed on the back surface of the sheet material, peeling of the sheet material is likely to occur at the edges of the sheet material. With this configuration, by wrapping the base resin around the gap, the portion of the edge of the sheet material that corresponds to the gap is covered on both the front and back surfaces by the base resin layer. This makes it possible to suppress peeling or the progression of peeling of the sheet material at the edges of the sheet material, improving the durability of the insert-molded product. In this specification, "peeling of the sheet material" refers to peeling of the sheet material from the base resin layer, and, if the sheet material has a laminated structure, peeling at the interface between the layers that make up the sheet material.

In this configuration , the molding die is
a cavity mold in which the sheet material is placed;
a core mold that is closed with the cavity mold at their mating surfaces to form a cavity into which the base resin is injected,
the step portion is formed by an end portion of the mating surface of the core mold on the cavity side protruding toward the cavity side or receding in a direction away from the cavity side relative to an end portion of the mating surface of the cavity mold on the cavity side when the cavity mold and the core mold are closed together,
In the placement process, the sheet material is placed in the cavity mold so that the surface of the sheet material contacts the surface of the cavity mold and a portion of the edge side of at least one of the notch and opening protrudes from the end of the cavity mold toward the core mold.

With this configuration, a step can be created by adjusting the relative position of the sheet-side edge on the mating surfaces of the cavity mold and core mold, thereby achieving a wraparound flow of the base resin with a simple configuration. This makes it possible to suppress peeling or the progression of peeling at the edge of the sheet material with a simple configuration.

Another aspect of the method for producing an insert molding product disclosed herein is
A method for manufacturing an insert-molded product including a sheet material and a base resin layer formed on a back surface of the sheet material,
an end processing step of continuously forming at least one of a concave-convex cutout portion and a plurality of openings in the end portion of the sheet material along the edge of the end portion;
a placement step of placing the sheet material in a mold;
an injection step of injecting a base resin, which is a raw material for the base resin layer, onto the back surface side of the sheet material,
the forming die has a step portion that is convex or concave toward the sheet material at a position facing at least one of the notch portion and the opening portion at an end of the sheet material when the sheet material is placed in the forming die,
a gap is formed between a part of an edge of the sheet material and the molding die by the step portion when the sheet material is placed in the molding die,
In the injection step, the base resin is injected into the gap through at least one of the notch and the opening,
In the end processing step, the concave-convex notch is formed.
It is characterized by:
In an insert-molded product having a sheet material and a base resin layer formed on the back surface of the sheet material, peeling of the sheet material is likely to occur at the edge of the sheet material. According to this configuration, by wrapping the base resin around the gap, the portion of the edge of the sheet material corresponding to the gap is covered by the base resin layer on both the front and back surfaces. This makes it possible to suppress peeling or the progression of peeling of the sheet material at the edge of the sheet material, and improve the durability of the insert-molded product.
Furthermore, the concave-convex cutouts are formed in the edge processing step. According to this configuration, the processing of the edge of the sheet material only requires the formation of the concave-convex cutouts, so that the wraparound of the base resin can be achieved with a simple configuration.
In the other aspect , the mold is
a cavity mold in which the sheet material is placed;
a core mold that is closed with the cavity mold at their mating surfaces to form a cavity into which the base resin is injected,
The step portion is preferably formed on at least one of the cavity mold and the core mold.

This configuration allows the base resin to flow around the mold cavity with a simple structure, simply by providing a step in at least one of the cavity mold and the core mold. This simple structure also makes it possible to prevent peeling or the progression of peeling at the edges of the sheet material.

In the above aspect, it is preferable that the uneven notch portion is formed in the end processing step.

With this configuration, the only processing required on the edge of the sheet material is to form concave and convex cutouts, allowing the base resin to flow around with a simple configuration.

Furthermore, it is preferable that the gap be formed continuously in correspondence with at least one of the notch and the opening.

Because the gaps are continuously formed in correspondence with at least one of the notches and openings, the base resin can be continuously introduced around the edge of the sheet material in the area where at least one of the notches and openings is provided. This effectively prevents peeling or the progression of peeling of the sheet material at the edge of the sheet material.

Furthermore, it is preferable that the end portion where at least one of the notch and the opening is provided extends from the center of the sheet material so as to bend toward the back surface of the sheet material.

The edges of the sheet material are bent toward the back surface of the sheet material, reducing the visibility of the areas covered by the base resin layer and preventing a loss of design appeal for the insert-molded product.

One aspect of the insert-molded product disclosed herein is an insert-molded product including a sheet material and a base resin layer formed on a back surface of the sheet material,
the end of the sheet material has at least one of a concave-convex cutout portion and a plurality of openings continuously formed along the edge of the end,
At least a part of the portion in the end portion where at least one of the notch portion and the opening portion is provided is characterized in that both the front and back surfaces of the sheet material are covered with the base resin layer.

At least a portion of the edge of the sheet material is covered on both the front and back surfaces with a base resin layer, effectively preventing peeling or the progression of peeling at the edge of the sheet material.

As described above, according to the present disclosure, a portion of the edge of the sheet material is covered on both the front and back surfaces with the base resin layer. This makes it possible to suppress peeling or the progression of peeling at the edge of the sheet material, thereby improving the durability of the insert-molded product.

1A and 1B are views showing an insert-molded product according to a first embodiment. 10A to 10C are diagrams showing modified shapes of the end portions of the sheet material. FIG. 2 is a flow diagram illustrating a method for manufacturing an insert-molded product according to the first embodiment. FIG. 10 is a diagram for explaining the procedure of a preparation process. 4A to 4C are diagrams for explaining a placement step, a mold closing step, and an injection step. FIG. 4 is a diagram for explaining the arrangement of the end portion of the sheet material. 7A and 7B are cross-sectional views taken along lines B1-B1 and B2-B2 in FIG. 6. 8A and 8B are diagrams for explaining the state after the base resin is injected and the flow of the base resin in FIG. 7; 7A and 7B are views illustrating a manufacturing method of an insert-molded product according to a second embodiment. 8 for explaining the state after the base resin is injected and the flow of the base resin in FIG. 9. FIG. FIG. 10 is a view equivalent to FIG. 1 showing an insert-molded product according to a second embodiment. 1 is a cross-sectional view showing a specific example of an insert molded product according to the present disclosure.

Embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The following description of the preferred embodiment is merely exemplary in nature and is in no way intended to limit the present disclosure, its applications, or its uses.

(Embodiment 1)
<Insert molding>
As shown in Fig. 1, an insert-molded product 100 according to this embodiment includes a sheet material 110 and a base resin layer 130 formed on the back surface of the sheet material 110. Fig. 1(a) is a perspective view of the insert-molded product 100, and Figs. 1(b) and 1(c) are cross-sectional views taken along lines A1-A1 and A2-A2 in Fig. 1(a), respectively.

The uses of the insert molded product 100 are not limited, but examples include interior and exterior vehicle parts, housings and decorative parts for electronic devices, home appliances, building materials, and furniture, and particularly parts that require high design quality.

<Sheet material>
There are no limitations on the material of the sheet material 110 as long as it is a sheet-shaped member. Specifically, the sheet material 110 may be, for example, a resin film, a woven fabric layer, a nonwoven fabric layer, a thin plate sheet, veneer, genuine leather, a thin metal sheet, etc. Furthermore, the sheet material 110 may have a layered structure in which multiple sheets made of a single type or multiple types of material are stacked on top of each other.

For example, the sheet material 110 may have a laminated structure including a resin layer with excellent weather resistance, light resistance, durability, etc., placed on the front side of the insert-molded product 100, a decorative layer laminated on the back side of the resin layer, and a fiber layer laminated on the back side of the decorative layer.

≪Base material resin layer≫
The base resin layer 130 can be made of a known base resin used in insert molding of sheet materials. While not intended to be limiting, specific examples of the base resin that can be used include acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), polycarbonate ABS (PC/ABS), glass fiber reinforced polycarbonate ABS (PC-ABS-GF), polycarbonate PBT (PC/PBT), polyamide (PA), and polypropylene (PP).

<Edge of sheet material>
As shown in FIG. 1, an end 111 of a sheet material 110 has a concave-convex cutout portion 112 formed continuously along an edge 111A of the end 111.

At least a portion of the portion of the end portion 111 where the cutout portion 112 is provided is covered by the base resin layer 130 on both the front surface 110A and the back surface 110B of the sheet material 110. More specifically, in this embodiment, the tip portion 112A of the cutout portion 112 is covered by the base resin layer 130. While the entire cutout portion 112 may be covered by the base resin layer 130 on both surfaces, in this embodiment, the front surface 110A of the base portion 112B of the cutout portion 112 is not covered by the base resin layer 130. In this way, it is sufficient that the both surfaces of at least a portion of the cutout portion 112 are covered by the base resin layer 130.

In this way, at least a portion of the surface 110A of the sheet material 110 at the end 111 of the sheet material 110 is covered by the base resin layer 130, so peeling of the sheet material 110 at the end 111 of the sheet material 110 can be effectively suppressed.

Although not intended to be limiting, the cutout portions 112 are preferably zigzag with a predetermined pitch P1. This facilitates processing of the end portions 111 in the sheet material 110 preparation step S1 (end processing step) described below. Although not intended to be limiting, the pitch P1 can be set to, for example, 1 mm or more and 10 mm or less in order to effectively prevent peeling of the sheet material 110 at the end portions 111. Furthermore, the width W1 of the cutout portions 112 is not particularly limited, but can be set to, for example, 1 mm or more and 10 mm or less, similar to the pitch P1.

The shape of the notch 112 is not limited to the above configuration. For example, as shown in Figure 2, the notch 112 may have a shape with a flat portion 112C at the tip 112A and/or base 112B, or, although not shown, may have a curved shape such as a wave shape.

Furthermore, the shape of the end portion 111 is not limited to the notch portion 112. Instead of or in combination with the notch portion 112, for example, multiple openings 114 may be formed continuously along the edge 111A. The shape of the openings 114 is not limited and may be circular as shown in FIG. 2, or may be polygonal, etc. The pitch P2 of the openings 114 can be set to the same as the pitch P1 of the notch portions 112, although this is not intended to be limiting. The diameter R1 of the openings 114 is not particularly limited and can be set appropriately depending on the pitch P2. The width W2 from the base end portion 114B of the openings 114 to the edge 111A can be set to the same as the width W1 of the notch portions 112, although this is not intended to be limiting.

As shown in FIG. 1, the end 111 having the cutout 112 preferably extends from the center 113 of the sheet material 110 so as to bend toward the back surface 110B of the sheet material 110. In other words, the end 111 and the center 113 are preferably connected by a bent portion 115. This reduces the visibility of the portion of the end 111 where both the front surface 110A and the back surface 110B are covered with the base resin layer 130, thereby preventing a decrease in the design of the insert-molded product 100.

<Method of manufacturing insert molding product>
An example of a method for manufacturing the insert molded product 100 according to this embodiment will be described.

As shown in Figure 3, the manufacturing method for the insert-molded product 100 includes a preparation process S1, a placement process S2, a mold closing process S3, an injection process S4, a cooling process S5, and a mold opening process S6.

≪Preparation process≫
The preparation step S1 is a step of preparing a sheet material 110.

Figure 4 shows an example of the procedure for the preparation step S1. First, a first precursor 105, which is the raw material for the sheet material 110, is prepared. If the first precursor 105 has a layered structure, raw material layers are prepared and layered to form the first precursor 105 for the sheet material 110 (layering step). Note that the layering step is an optional step and may be performed as needed. Furthermore, there are no limitations on the layering method, and any known method can be used.

As an example of the lamination process, if the sheet material 110 has a three-layer structure consisting of a resin layer, a decorative layer, and a fiber layer, the first precursor 105 can be obtained by laminating, for example, a resin film 101, which is the raw material for the resin layer, a decorative sheet 102, which is the raw material for the decorative layer, and a fiber sheet 103, which is the raw material for the fiber layer.

In particular, when the insert-molded product 100 is an interior or exterior vehicle part, conventionally, a decorative layer is applied to the molded base resin layer 130 by adhesive or other means, and then a primer coat, intermediate coat, and top coat are applied to improve the part's weather resistance, light resistance, durability, etc., to obtain the part. In contrast, in this method, the surface of the decorative layer is painted with a resin film 101, and a sheet material 110 with a three-layer structure consisting of a resin layer, a decorative layer, and a fiber layer is prepared in advance, and the base resin layer 130 is formed on this sheet material 110 by insert molding. Because this method does not require a painting step, it is advantageous over conventional methods because it simplifies the part manufacturing process and reduces manufacturing costs.

The resin film 101 is, for example, a single-layer or multi-layer film made of a transparent or translucent resin with a uniform thickness, and has excellent weather resistance, durability, etc., though this is not intended to be limiting. The resin material of the resin film 101 is, for example, an acrylic resin containing fluorine, though this is not intended to be limiting. The thickness of the resin film 101 is, for example, 0.05 mm to 3.0 mm, though this is not intended to be limiting.

The decorative sheet 102 may be, for example, a sheet of uniform thickness, and may be selected from, for example, veneer, genuine leather, thin-film metal sheet, polyvinyl chloride sheet, polyolefin sheet, urethane-coated paper, cork sheet, carbon sheet, etc. The thickness of the decorative sheet 102 is not limited, but may be, for example, 0.15 mm or more and 3.0 mm or less. The decorative sheet 102 may have a pattern, such as a grain pattern.

The fiber sheet 103 may be, for example, a cotton cloth or a resin cloth, although this is not intended to be limiting. The fiber sheet 103 may be a woven fabric or a nonwoven fabric. The thickness of the fiber sheet 103 is, for example, 0.15 mm or more and 3.0 mm or less, although this is not intended to be limiting.

Next, uneven notches 112 and/or openings 114 are continuously formed along the edge of the end of the first precursor 105 to obtain the second precursor 107 (end processing step). The method for forming the notches 112 and/or openings 114 is not limited, and known methods such as trimming and punching can be used.

It is preferable to form cutouts 112, which are easy to process, in the end portion 111, particularly zigzag cutouts 112 with a predetermined pitch P1. This makes it possible to prevent peeling of the end portion 111 of the sheet material 110 with a simple configuration.

Then, the second precursor 107 is shaped to obtain a sheet material 110 having the shape required for the insert-molded product 100 (shaping process). If the sheet material 110 has a bent portion 115, it is formed in the shaping process.

Note that the procedure for the preparation process S1 shown in Figure 4 describes an example in which the shaping process is performed after the end processing process, but the end processing process may be performed after the shaping process, or the shaping process and end processing process may be performed simultaneously. Furthermore, depending on the shape of the insert-molded product 100, the shaping process may not be necessary. In this case, the process can proceed to the next placement process S2 after the end processing process without performing the shaping process.

≪Placement process, mold closing process and injection process≫
Next, the placement step S2, mold closing step S3, and injection step S4 will be described with reference to FIGS.

Figure 5(a) shows an example of the placement process S2, and (b) shows an example of the mold closing process S3 and injection process S4.

As shown in Figure 5(a), in the placement step S2, the sheet material 110 is placed in the molding die 200.

Here, the molding die 200 comprises a cavity die 201 and a core die 203.

The sheet material 110 is placed in the cavity mold 201 so that the surface 110A of the sheet material 110 contacts the surface 201A of the cavity mold 201. The sheet material 110 placed in the cavity mold 201 is sucked by the suction device 231 through the suction passage 233 as needed. In this way, the sheet material 110 is restrained by the surface 201A of the cavity mold 201 (placement process S2). Note that if suction of the sheet material 110 by the suction device 231 is not necessary due to the shape of the insert-molded product 100, suction need not be performed.

As shown in Figures 6(a) and 7, the sheet material 110 is positioned so that the tip 112A (part of the edge) of the notch 112 formed in the end 111 protrudes from the end 201C of the cavity mold 201 toward the core mold 203. This allows the base resin 131, which is the raw material for the base resin layer 130, to flow around the surface 110A of the sheet material 110 at the notch 112, as described below.

Next, as shown in Figure 5(b), the cavity mold 201 and the core mold 203 are brought close together, and their mating surfaces, i.e., the mating surface 201B of the cavity mold 201 and the mating surface 203B of the core mold 203, are brought into contact and closed (mold closing step S3). Then, as shown in Figures 5, 7, and 8, the back surface of the sheet material 110, the surface 201A of the cavity mold 201, and the surface 203A of the core mold 203 form a cavity 205 into which the base resin 131 is injected.

At this time, as shown in Figure 7, the core mold 203 is configured so that the end 203C of its mating surface 203B on the cavity 205 side is positioned in a position that is set back in a direction away from the cavity 205 side relative to the end 201C of the mating surface 201B of the cavity mold 201 on the cavity 205 side. As a result, when the mold is closed, a step portion 207 is formed in the cavity 205 by the mating surface 201B of the cavity mold 201 and the mating surface 203B of the core mold 203.

As described above, the notch 112 of the sheet material 110 is positioned so that its tip 112A protrudes from the end 201C of the cavity mold 201 toward the core mold 203, and therefore the step 207 is a step that is recessed toward the sheet material 110 at a position opposite the notch 112.

As shown in the B1-B1 cross section of Figure 7, the step 207 forms a gap 208 between the notch 112 of the sheet material 110 and the core mold 203.

Next, as shown in FIG. 5(b), molten base resin 131 is injected into cavity 205 through introduction gate 204 (injection process). In this way, base resin layer 130 is formed on rear surface 110B of sheet material 110.

The manufacturing method for the insert-molded product 100 according to this embodiment is characterized in that when the base resin 131 is injected, it flows into the gap 208 formed by the cutout 112 and the step 207.

As shown in the B1-B1 and B2-B2 cross-sectional views of Figure 8, when the base resin 131 is injected, the pressure of the base resin 131, indicated by the arrows in the figure, presses most of the sheet material 110 against the surface 201A of the cavity mold 201. Meanwhile, due to the presence of the gap 208, it takes some time for the tip 112A of the cutout 112 to be pressed against the surface of the step 207. Then, as indicated by the arrow in the lower view of Figure 8, the base resin 131 flows into the gap 208 through the inlet 112D formed between the base end 112B of the cutout 112 and the end 201C of the cavity mold 201. As a result, the base resin can be introduced around the surface 110A side of the tip 112A of the cutout 112, as shown in the B1-B1 cross-sectional view of Figure 8.

With this configuration, by having the base resin 131 wrap around the gap 208, the tip 112A of the notch 112 is covered by the base resin layer 130 on both the front surface 110A and the back surface 110B. This prevents the sheet material 110 from peeling or the progression of peeling at the end 111 of the sheet material 110, improving the durability of the insert-molded product 100.

6(b), when the cutout 112 is closer to the cavity mold 201 than the end 201C of the cavity mold 201, i.e., when the entire surface 110A of the cutout 112 is in contact with the surface 201A of the cavity mold 201, the base resin 131 does not flow around. This is because the base resin 131 presses the entire surface 110A of the cutout 112 against the surface 201A of the cavity mold 201. Also, when the cutout 112 protrudes toward the core mold 203 than the end 201C of the cavity mold 201, i.e., when the entire surface 110A of the cutout 112 forms a gap 208, as shown in FIG. 6(c), the base resin 131 does not flow around. This is because the entire surface 110A of the cutout 112 is pressed against the surface of the step 207 by the base resin 131, since the inlet 112D is not formed. Therefore, it is important to position the sheet material 110 in the cavity mold 201 so that the tip 112A, which is part of the cutout 112, protrudes from the end 201C of the cavity mold 201 toward the core mold 203.

Also, as shown in Figure 2, even if the shape of the cutout portion 112 is changed and/or an opening portion 114 is provided, the position of the end portion 201C of the cavity mold 201 must be positioned at a position corresponding to the cutout portion 112 and/or opening portion 114.

In this configuration, the step portion 207 is formed by adjusting the relative positions of the end portion 201C of the cavity mold 201 and the end portion 203C of the core mold 203. This makes it possible to achieve wraparound of the base resin 131 around the cutout portion 112 with a simple configuration without requiring major design changes to the molding mold 200.

Furthermore, it is preferable that the step portion 207 is continuously formed at a position corresponding to the notch portion 112 and/or opening 114 of the sheet material 110. As a result, the gap portion 208 is continuously formed corresponding to the notch portion 112 and/or opening 114, so that the base resin 131 can be caused to flow continuously around the notch portion 112 and/or opening 114. In this way, peeling or the progression of peeling of the sheet material 110 at the edge portion 111 of the sheet material 110 can be effectively suppressed.

≪Cooling process and mold opening process≫
After the injection of the base resin 131 is completed, the base resin 131 is cooled, for example, from the injection temperature to the mold temperature at a constant cooling rate. The base resin 131 is then solidified to form the base resin layer 130 (cooling step S5). After the base resin 131 has solidified, the cavity mold 201 and the core mold 203 are opened, and the insert-molded product 100 is released (mold-opening step S6).

(Embodiment 2)
Other embodiments of the present disclosure will be described in detail below. In the description of these embodiments, the same parts as those in the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted.

In embodiment 1, the end 203C of the core mold 203 is configured to be positioned further back in the direction away from the cavity 205 than the end 201C of the cavity mold 201, but this configuration is not limited to this. The end 203C of the core mold 203 may also be configured to protrude further toward the cavity 205 than the end 201C of the cavity mold 201, as shown in FIG. 9 .

As a result, the step portion 207 becomes a step portion that is convex toward the sheet material 110 at a position opposite the cutout portion 112.

As shown in the B1-B1 cross section of Figure 9, the step 207 forms a gap 208 between the base end 112B of the notch 112 of the sheet material 110 and the cavity mold 201.

In this configuration, when the base resin 131 is injected, it flows through the inlet 112D into the gap 208 formed between the base end 112B of the cutout 112 and the cavity mold 201, as shown in Figure 10.

As a result, an insert-molded product 100 is obtained in which the surface 110A at the base end 112B of the cutout portion 112 is covered with the base resin layer 130, as shown in Figures 11(a) to 11(c).

In either configuration of Embodiments 1 or 2, if the wrap-around speed of the base resin 131 is sufficiently fast, the base resin 131 may wrap around a wider area or the entire surface 110A of the cutout portion 112. In this case, a wider area or the entire surface 110A of the cutout portion 112 will be covered by the base resin layer 130.

(Other embodiments)
In the configurations of the first and second embodiments, the step portion 207 is formed by adjusting the relative positions of the end portion 201C of the cavity mold 201 and the end portion 203C of the core mold 203, but this is not limited to this configuration. The step portion 207 may be formed on at least one of the cavity mold 201 and the core mold 203, preferably on the cavity mold 201 or the core mold 203. Specifically, for example, the step portion 207 may be provided around the end portion 201C of the cavity mold 201 or around the end portion 203C of the core mold 203. In this case, although not shown, the sheet material 110 may be positioned so that, when the mold is closed, the tip 112A (part of the edge side) of the notch 112 formed in the end 111 of the sheet material 110 and/or a part of the edge 111A side of the opening 114 protrudes from the end of the stepped portion 207 that contacts the sheet material 110 (this end corresponds to the end 201C in embodiment 1 and the end 203C in embodiment 2) toward the core mold 203. From the viewpoint of simplifying the configuration of the molding mold 200, the configurations of embodiments 1 and 2 are desirable.

Furthermore, the cutout portion 112 and/or opening 114 do not have to be provided over the entire end portion 111 of the sheet material 110.

Specifically, Figure 12 shows an example of an insert-molded product 100, an automotive interior part. The end 111 of this part, located at the top of Figure 12, has a cutout 112, and a portion of the surface 110A of the cutout 112 is covered with a base resin layer 130. On the other hand, the surface 110A of the end 111, located at the bottom of Figure 12, is in contact with a plated decorative part 401. Because the end 111 is pressed by the plated decorative part 401, there is little chance of it peeling off. Therefore, in areas where peeling is suppressed by the presence of other parts, for example, it is not necessary to provide the cutout 112 and/or opening 114.

This disclosure is extremely useful because it can more reliably suppress peeling of sheet material at the edges of insert-molded products with a simple configuration, thereby improving the durability of the insert-molded product.

100 Insert molded product 110 Sheet material 110A Surface 110B Back surface 111 End 111A Edge 112 Notch portion 112A Tip portion 112B Base end portion 112D Inlet 113 Central portion 114 Opening 115 Bent portion 130 Base resin layer 131 Base resin 200 Mold 201 Cavity mold 201A Surface 201B Mating surface 201C End 203 Core mold 203A Surface 203B Mating surface 203C End 205 Cavity 207 Step portion 208 Gap portion S1 Preparation process (end processing process)
S2 Placement process S4 Injection process

Claims (6)

A method for manufacturing an insert-molded product including a sheet material and a base resin layer formed on a back surface of the sheet material,
an end processing step of continuously forming at least one of a concave-convex cutout portion and a plurality of openings in the end portion of the sheet material along the edge of the end portion;
a placement step of placing the sheet material in a mold;
an injection step of injecting a base resin, which is a raw material for the base resin layer, onto the back surface side of the sheet material,
the forming die has a step portion that is convex or concave toward the sheet material at a position facing at least one of the notch portion and the opening portion at an end of the sheet material when the sheet material is placed in the forming die,
a gap is formed between a part of an edge of the sheet material and the molding die by the step portion when the sheet material is placed in the molding die,
In the injection step, the base resin is injected into the gap through at least one of the notch and the opening,
The above-mentioned mold is
a cavity mold in which the sheet material is placed;
a core mold that is closed with the cavity mold at their mating surfaces to form a cavity into which the base resin is injected,
the step portion is formed by an end portion of the mating surface of the core mold on the cavity side protruding toward the cavity side or receding in a direction away from the cavity side relative to an end portion of the mating surface of the cavity mold on the cavity side when the cavity mold and the core mold are closed together,
In the placing step, the sheet material is placed in the cavity mold so that the surface of the sheet material contacts the surface of the cavity mold and a part of the edge side of at least one of the notch portion and the opening portion protrudes from the end portion of the cavity mold toward the core mold.
A method for manufacturing an insert molded product characterized by the above-mentioned. A method for manufacturing an insert-molded product including a sheet material and a base resin layer formed on a back surface of the sheet material,
an end processing step of continuously forming at least one of a concave-convex cutout portion and a plurality of openings in the end portion of the sheet material along the edge of the end portion;
a placement step of placing the sheet material in a mold;
an injection step of injecting a base resin, which is a raw material for the base resin layer, onto the back surface side of the sheet material,
the forming die has a step portion that is convex or concave toward the sheet material at a position facing at least one of the notch portion and the opening portion at an end of the sheet material when the sheet material is placed in the forming die,
a gap is formed between a part of an edge of the sheet material and the molding die by the step portion when the sheet material is placed in the molding die,
In the injection step, the base resin is injected into the gap through at least one of the notch and the opening,
In the end processing step, the concave-convex notch is formed.
A method for manufacturing an insert molded product characterized by the above-mentioned. In claim 2 ,
The above-mentioned mold is
a cavity mold in which the sheet material is placed;
a core mold that is closed with the cavity mold at their mating surfaces to form a cavity into which the base resin is injected,
The method for manufacturing an insert-molded product is characterized in that the step portion is formed in at least one of the cavity mold and the core mold. In claim 1 ,
A method for manufacturing an insert-molded product, characterized in that the uneven notch portion is formed in the end processing step. In any one of claims 1 to 4,
A method for manufacturing an insert-molded product, wherein the gap is formed continuously in correspondence with at least one of the notch and the opening. In any one of claims 1 to 5,
A method for manufacturing an insert molded product, characterized in that the end portion where at least one of the cutout portion and the opening portion is provided extends so as to bend from the center of the sheet material to the back side of the sheet material.