Molding mold, method for manufacturing molding mold, and method for manufacturing molded product

Abstract

The invention provides a molding die, a method for manufacturing the molding die, and a method for manufacturing a molded article, wherein the possibility of clogging of micropores can be reduced. A molding die (1), which is formed from a steel material and has a surface section (11) that serves as a contact surface with a molded article, has formed therein micropores (12) that pass through the surface section (11) and serve as air flow paths, and has a plating layer (PL) that is applied to the surface section (11) and the inner walls (12a) of the micropores (12) by means of a rust-proof metal that prevents rust.

Description

Technical Field

[0001] The present invention relates to a molding die, a method for manufacturing the molding die, and a method for manufacturing a molded product. Background Art

[0002] In the past, molding dies for manufacturing various products are known. Among such molding dies, molding dies are also known in which fine through holes (micropores) are formed on the mold to serve as air circulation paths in order to be able to perform vacuum molding, etc., which attracts specific parts while molding. Molds with micropores can be made by an electroforming process. For example, in a nickel electroforming process, a conductive layer is formed on the surface of a mandrel, and a plurality of tiny non-conductive portions are provided on the surface of the conductive layer. By electroforming on the surface of the mandrel, a nickel electroformed shell with micropores formed on the mold can be obtained. The nickel electroformed shell constitutes the surface of the molding die.

[0003] However, it takes a lot of time, for example, more than one and a half months, to produce a nickel electroformed shell in the above nickel electroforming process. Therefore, a technique for producing a forming die having micropores by cutting steel has been proposed (see, for example, Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-81600 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, since the molding die described in Patent Document 1 is made by cutting steel, it may rust due to the type of resin used in product manufacturing, the humidity environment in which the die is placed, etc., and the rust may peel off and enter the micropores to cause clogging. Therefore, in order to prevent rust, it is considered to apply a rust inhibitor to the die, but the rust inhibitor itself is in a state of entering the micropores and sometimes becomes a cause of clogging. In addition, in addition to cutting steel, a die of steel with micropores can also be made by casting, but even in this case, the problem of rust will occur, so the problem of clogging will also occur.

[0009] The present invention has been made to solve such conventional problems, and an object of the present invention is to provide a molding die, a method for manufacturing the molding die, and a method for manufacturing a molded product, which can reduce the possibility of clogging of micropores.

[0010] Means of solving problems

[0011] In order to solve this problem, the molding die involved in the present invention is formed of steel and has a surface portion that serves as a contact surface with the molded product. The molding die is formed with micropores that penetrate through the surface portion to serve as air circulation paths, and has a coating applied to the surface portion and the inner walls of the micropores with a rust-proof metal that prevents rust.

[0012] In addition, the manufacturing method of the molding die involved in the present invention comprises: a first step of making a basic main body part from a steel material, wherein the basic main body part has a surface part that becomes a contact surface with the molded product; a second step of forming micropores, wherein the micropores become a through-state from the surface part of the basic main body part made in the first step and become a circulation path for air; and a third step of plating the surface part formed in the first step and the inner wall of the micropore formed in the second step with a rust-proof metal to prevent rust.

[0013] Furthermore, the method for producing a molded article according to the present invention produces a molded article using the above-described molding die.

[0014] Effects of the Invention

[0015] According to the present invention, it is possible to provide a molding die, a method for manufacturing a molding die, and a method for manufacturing a molded product, which can reduce the possibility of clogging of micropores. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a cross-sectional view showing the structure of the molding die according to the present embodiment.

[0017] Figure 2 Yes means Figure 1 An enlarged view of the periphery of the micropore is shown.

[0018] 3 is a process diagram showing a method for manufacturing a molding die according to the present embodiment, wherein FIG. 3( a ) shows a steel material processing step, FIG. 3( b ) shows an embossing step, and FIG. 3( c ) shows a micro-hole processing step.

[0019] Figure 4 It is a process diagram showing the method for manufacturing the forming die according to the present embodiment, and shows a modified example of the steel material processing process.

[0020] Explanation of symbols

[0021] 1 Molding mold

[0022] 10 upper mold

[0023] 10a Hollow part

[0024] 10b Back side

[0025] 11 Surface

[0026] 12 Micropores

[0027] 12a Inner wall

[0028] 20 Lower die

[0029] 21 Surface

[0030] FB basic body

[0031] PL coating DETAILED DESCRIPTION

[0032] Hereinafter, the present invention will be described according to preferred embodiments. In addition, the present invention is not limited to the embodiments shown below, and can be appropriately changed within the scope of not departing from the gist of the present invention. In addition, in the embodiments shown below, although there are places where the illustration and description of a part of the structure are omitted, the details of the omitted technology are of course applicable to the known or well-known technology within the scope that does not conflict with the content described below.

[0033] Figure 1 2 is a cross-sectional view showing the structure of the molding die according to the present embodiment. Figure 1 As shown, the molding die 1 involved in this embodiment is made of steel and has an upper mold 10 and a lower mold 20. In such a molding die 1, for example, an injection device not shown in the figure is connected, and a molded product with a shape corresponding to the space S is manufactured by injecting and filling the heated and molten resin into the space S clamped by the upper mold 10 and the lower mold 20. In addition, the molding die 1 is not limited to a mold for injection molding, and can also be a mold for closing a sheet, or a mold for closing a sheet after setting a molded core material and then evacuating the sheet, etc., and there is no particular limitation on the molding method. In addition, in this embodiment, the configuration relationship between the upper mold 10 and the lower mold 20 can also be reversed.

[0034] In such a molding die 1, the upper mold 10 is embossed on the surface 11. The surface 11 is a portion that becomes a contact surface with the molded product and is a portion that determines the outer shape of the molded product. By embossing the surface 11, fine patterns and the like are expressed in the molded product.

[0035] Furthermore, the upper mold 10 is formed to have a predetermined plate thickness, and the back side of the surface portion 11 forms a cavity portion 10a. Figure 1 In the embodiment, the hollow portion 10a is a complete hollow, but is not limited thereto and may be filled with aluminum grids, etc. In addition, the upper mold 10 may have a thickness sufficient to maintain the shape during molding, and in particular, a thickness sufficient to ensure that no deformation or the like occurs even if a plurality of micropores 12 described later are formed.

[0036] In addition, the upper mold 10 is formed with a plurality of micropores 12 that are in a through-state from the surface portion 11 and serve as a circulation path for air. The aperture of each micropore 12 is a size that does not affect the surface of the molded product. The plurality of micropores 12 are used, for example, to absorb the surface material when molding vehicle interior parts or to perform embossing transfer. In addition, the use of the plurality of micropores 12 is not particularly limited thereto, and for example, it can also be used for other purposes such as supplying compressed air, as long as it serves as a circulation path for air.

[0037] The lower mold 20 is paired with the upper mold 10. In the present embodiment, the back side of the surface portion 21 of the lower mold 20 does not become a hollow portion and does not have micropores. In addition, the lower mold 20 is not particularly limited to this, and may have a hollow portion or a hole.

[0038] Furthermore, in the present embodiment, the upper mold 10 and the lower mold 20 have a plating layer formed of a rust-proof metal. Here, the rust-proof metal refers to at least one of steel, nickel, chromium, zinc, gold, silver, rhodium, platinum and palladium or an alloy containing them, which has a rust-proof effect. In addition, the lower mold 20 may not be plated with a rust-proof metal and may not have a plating layer.

[0039] As described above, in the present embodiment, at least the surface portion 11 of the upper mold 10 is coated with the rust-proof metal plating. Figure 2 Yes means Figure 1 FIG. 1 is an enlarged view of the periphery of the micropore 12 shown in FIG. Figure 2 As shown, in the upper mold 10 , the plating layer PL is formed of a rust-proof metal not only on the surface portion 11 but also on the inner wall 12 a of the microhole 12 .

[0040] By performing the plating coating as described above, it is prevented that the inner wall 12 a of the micropore 12 is directly rusted and clogged, or that the rust on the surface portion 11 or 21 is peeled off and enters the micropore 12 and clogs.

[0041] Here, since the upper mold 10 has the cavity 10a, it is preferable that the back side 10b of the cavity 10a, which is the back side of the surface 11, also forms a plating layer PL of a rust-proof metal. This is because it prevents rust generated on the back side from peeling off and entering the micropores 12 to cause clogging.

[0042] Next, the manufacturing method of the molding die 1 involved in this embodiment is described. Fig. 3 is a process diagram showing the manufacturing method of the molding die 1 involved in this embodiment, Fig. 3 (a) shows the steel material processing step, Fig. 3 (b) shows the embossing process, and Fig. 3 (c) shows the micro-hole processing step. In addition, Fig. 3 shows the manufacturing method of the upper mold 10 in the molding die 1.

[0043] First, as shown in Fig. 3(a), a base body FB having a surface portion 11 corresponding to the shape of a molded product is manufactured (steel material processing step: first step). In the steel material processing step, for example, a steel material block is cut or cast to manufacture the base body FB.

[0044] Next, as shown in Fig. 3(b), the surface portion 11 of the base body portion FB is embossed (embossing process). In the embossing process, the surface portion 11 is embossed by etching, laser or NC machining (numerical control machining).

[0045] Furthermore, when NC processing is performed, the steel material processing step and the embossing step may be performed in the same step. This is because the manufacturing process can be simplified to one step.

[0046] After the embossing process, as shown in FIG. 3( c ), micropores 12 are formed from the surface portion 11 to be in a through state (micropore processing process: second process). In the micropore processing process, the micropores 12 are formed by discharge, drilling, laser or NC processing, etc. In addition, if the micropores 12 are in a through state in a form including the surface portion 11, they can be formed to be through from the surface portion 11, and can also be formed to be through from the back portion 10 b.

[0047] In addition, in the present embodiment, the micropore processing step is performed after the embossing processing step, but the order may be reversed. However, it is advantageous to perform the embossing processing step first in terms of manufacturing. This is because, for example, if the micropores 12 are formed first and then the embossing processing is performed, the inner wall of the micropores 12 is irradiated with a laser for forming the embossing, or an etching liquid enters the micropores 12, etc., thereby increasing the size of the micropores 12 and leaving traces of the micropores 12 on the molded product.

[0048] Next, the base body FB having the micropores 12 formed therein is plated with a rust-proof metal (coating step: the third step). In the coating step, for example, the base body FB is immersed in a plating tank, and a plating layer PL made of a rust-proof metal is formed on the entire surface area of ​​the base body FB (not only the surface part 11 but also the entire area of ​​the inner wall 12a of the micropores 12 and the cavity 10a) (see Figure 2 ). In addition, the plating layer PL formed by the rust-proof metal is not limited to the entire surface area of ​​the base body part FB, and can also be formed only on the surface part 11 and the inner wall 12a of the micropore 12, and can also be formed on the back side 10b which is the back side of the surface part 11. In addition, the plating layer PL is not limited to immersing the base body part FB in a plating tank, and can also be formed by, for example, vapor deposition.

[0049] Thus, according to the molding die 1 and the manufacturing method of the molding die 1 involved in the present embodiment, since the plating layer PL is formed on the surface portion 11 and the inner wall 12a of the micropore 12 which becomes a through state from the surface portion 11 and becomes a flow path of air, it is possible to suppress rusting of the surface portion 11 of the steel material and the inner wall 12a of the micropore 12 and suppress the occurrence of clogging caused by rust. In addition, it is not necessary to apply a rust inhibitor, and the occurrence of clogging caused by the rust inhibitor can also be suppressed. Therefore, it is possible to provide a molding die 1 and a manufacturing method of the molding die 1 that can reduce the possibility of clogging of the micropore 12.

[0050] In addition, when the base body FB having the hollow portion 10a is produced on the back side of the surface portion 11, the amount of steel used can be reduced for the hollow portion 10a on the back side that is not necessary during molding. Furthermore, since the back portion 10b is also plated with a rust-proof metal, the possibility of clogging due to rust generated on the back portion 10b of the hollow portion 10a can be reduced.

[0051] Furthermore, according to the present embodiment, since the steel material is processed, the electroforming process is not required, and the mold construction period can be shortened. In addition, the mold cost can be reduced along with the shortening of the mold construction period. Furthermore, in the case of manufacturing by cutting a steel block, the dimensional accuracy based on machining can be improved. In addition, by using steel, the shape can be easily maintained compared to the case of using a nickel electroforming shell. Furthermore, compared to the case of going through the electroforming process, a complex mold structure such as a sliding mold can also be realized.

[0052] In addition, as in the past, when the electroforming process is passed, the mold structure is formed by supporting the nickel electroforming shell with an aluminum grid or the like, but when steel is used, the thermal conductivity can be lower than that of the previous structure, and the mold can be difficult to cool. Therefore, when the mold is heated for use, the mold can be easily kept warm to suppress the generation of shock lines.

[0053] Furthermore, according to the manufacturing method of the molded product involved in this embodiment, since the above-mentioned molding die 1 is used, it is manufactured by the molding die 1 that reduces the possibility of clogging of the micropores 12, and can provide a molded product with improved quality by appropriately performing processes such as absorbing the surface material or performing embossing transfer.

[0054] As mentioned above, the present invention has been described based on the embodiments, but the present invention is not limited to the above-mentioned embodiments, and changes can be made within the scope not departing from the gist of the present invention, and known or well-known technologies can be combined if possible.

[0055] For example, in the above embodiment, the micropores 12 are formed only in the upper mold 10 and the inner walls 12a thereof are plated, but the present invention is not limited to the upper mold 10, and the micropores may be formed in the lower mold 20 and the inner walls may be plated. Furthermore, in the case of having a third or later mold other than the upper mold 10 and the lower mold 20, the surface portion of the third or later mold and the inner walls of the micropores may be plated.

[0056] In addition, in this embodiment, it is assumed that the forming die 1 is used for vacuum forming, but it is not particularly limited to vacuum forming. In addition, although the forming die 1 involved in this embodiment is embossed, it is not necessary to perform embossing.

[0057] Furthermore, although the example in which the base body portion FB is produced by cutting a steel block in the above-mentioned steel material processing step has been described, the present invention is not particularly limited thereto. Figure 4 FIG. 2 is a process diagram showing a method for manufacturing a forming die according to the present embodiment, showing a modified example of a steel material processing process. Figure 4 In the example shown, the base body portion FB is composed of a contact portion FB1 and a side portion FB2. The contact portion FB1 is a portion that contacts the molded product when the molded product is manufactured, and is a portion corresponding to the above-mentioned surface portion 11 and the back portion 10b. The side portion FB2 is a portion assembled to the contact portion FB1. Figure 4 In the modification shown, the contact part FB1 and the side part FB2 are manufactured separately, and then the two FB1 and FB2 are assembled. In this way, in the steel material processing step related to the modification, each part FB1 and FB2 can also be manufactured separately and then assembled.

Claims

1. A molding die, characterized in that: The molding die is formed of a steel material and has a surface portion that becomes a contact surface with the molded product. The molding die has micropores penetrating from the surface portion to serve as air flow paths, and has a plating layer formed on the surface portion and inner walls of the micropores with a rustproof metal for preventing rust.

2. A method for manufacturing a molding die, characterized in that: have: In a first step, a base body portion is made of a steel material, wherein the base body portion has a surface portion that becomes a contact surface with the molded product; A second step of forming micropores, wherein the micropores penetrate the surface portion of the base body portion produced in the first step and serve as air flow paths; as well as In the third step, the surface portion formed in the first step and the inner wall of the micropore formed in the second step are plated with a rust-proof metal for preventing rust.

3. The method for manufacturing a molding die according to claim 2, characterized in that: In the first step, the base body portion having a cavity portion on the back side of the surface portion is produced. In the third step, a back surface portion of the cavity portion, which is a back surface side of the surface portion, is plated with the rust-proof metal.

4. A method for manufacturing a molded product, characterized in that: A molded product is produced using the molding die according to claim 1.

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