JP2002307479A - Method for producing plastic molding with texture pattern and mold to be used in the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a texture pattern on the surface of a molding simultaneously with the molding of the entire molding. SOLUTION: A method includes a preheating process in which a skin material 1 sheet having a thermoplastic plastic layer on the surface side is heated at a prescribed temperature, a skin material setting process for molding the heated skin material 1 in a prescribed form in which the heated skin material 1 is set in a mold composed of a female mold 9 having a prescribed texture pattern mold 91 and an evacuation means 92, etc., so that the surface side of the skin material 1 is arranged on the female mold 9 side, a mold clamping process in which molds 9 and 8 are clamped with the skin material 1 set, an injection process in which while evacuation is done from the side of the female mold 9, a prescribed plastic material is injected on the back side of the skin material 1, and a mold opening process (E) in which after the evacuation process and the injection process, the molds 8 and 9 are opened to remove the molding with the texture pattern which is formed in a prescribed form.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a plastic molded article having a grain pattern and a mold used in the production method. In particular, a grain pattern is provided in advance on a part of the mold. The present invention also relates to a method for producing a plastic molded body having a grain pattern on the surface, wherein the above-mentioned grain pattern is formed simultaneously with the molding of the present plastic molded article by using such a mold.

[0002]

2. Description of the Related Art In a conventional method for producing a plastic molded article having a textured surface, a sheet-shaped member having a textured surface is prepared in advance on a surface layer of a skin material, and a back surface of such a skin material is For example, by installing a thermoplastic material using a predetermined molding means, such as injection molding means,
Thus, a plastic molded body having a predetermined form is formed.

[0003]

As described above, in the conventional method, a skin material having a grain pattern on its surface is prepared in advance, and such a skin material is placed in a mold and the back surface thereof is provided. A plastic molded body with a grain pattern is formed (manufactured) by injecting a predetermined plastic material into the side, and the overall efficiency (productivity) of the manufacturing process is largely divided into two processes. ) Is not good. In order to solve such a problem, a mold used in the molding process is prepared with a crimped pattern provided on its inner surface in advance, and by using such a mold, the skin material is An object of the present invention is to provide a method for producing a plastic molded body having a grain pattern, in which the formation of a grain pattern on a surface layer and the molding of a plastic molded body are performed simultaneously and together. Subject).

[0004]

Means for Solving the Problems In order to solve the above problems, the present invention takes the following measures. That is, in the invention according to claim 1, with respect to a method for producing a plastic molded body having a grain pattern on the surface, a sheet-like material having a foamed plastic material inside and having a thermoplastic plastic layer on the surface side is provided. A preheating step of heating the skin material to a predetermined temperature, and forming the skin material heated to a predetermined temperature in the preheating step into a predetermined form, and a predetermined grain pattern on the female mold side. And, in a mold having vacuum evacuation means, while installing so that the surface side of the preheated skin material comes to the female mold side, a mold clamping step of clamping the mold in such a state, In the state of being clamped in this manner, an injection step of injecting a predetermined plastic material into the back surface side of the skin material while performing vacuum evacuation from the female mold side, Was to so that.

[0005] By adopting such a process, in the present invention, the grain pattern present on the surface can be formed at the same time as the molding of the plastic molded article. The efficiency of the process can be improved. That is, at the time of injection (at the time of injection) of the plastic material forming the basis of the plastic molded body, the grain pattern provided on the inner surface side of the female mold is replaced with the thermoplastic plastic material forming the surface side of the skin material. The transfer is performed, and the step of forming the grain pattern is shortened. As a result, the entire manufacturing process of the present plastic molded body with a grain pattern is shortened, and the productivity is improved.

Next, the invention according to claim 2 will be described. This is also basically the same as the first aspect. That is, in the present invention, with respect to the method for producing a plastic molded article having a grain pattern according to claim 1, the skin material used in the production method has a sheet material made of an olefin-based elastomer on the surface side. In the middle, a foam made of a polypropylene foam material was provided, and further, a sheet material made of a polypropylene resin was provided on the back surface side. By using such a skin material, in the case of the present invention, a grain pattern is efficiently formed on the surface of the skin material in a vacuuming step performed simultaneously with the injection step. Therefore,
A plastic molded body having a grain pattern on such a surface is efficiently formed (manufactured), and the overall productivity is improved.

Next, the invention according to claim 3 will be described. This is also basically the same as the first aspect. That is, in the present invention, with respect to the method for producing a plastic molded article having a grain pattern according to claim 1, the skin material used in the production method has a sheet material made of an olefin-based elastomer on the surface side. In the middle, a foam made of a polyurethane foam material was provided, and further, a nonwoven fabric was provided on the back side. By using such a skin material, according to the present invention, the above-mentioned claim 1 is used.
Alternatively, as in the case of the second aspect, the formation of a grain pattern on the surface of the skin material can be performed efficiently, and the bonding (integration) of the injected plastic material and the skin material forming the base of the present plastic molded article. Is performed smoothly through the nonwoven fabric. As a result, the production efficiency of the entire plastic molded body is improved.

Next, the invention according to claim 4 will be described. A feature of the present invention resides in a mold used in a method of manufacturing a plastic molded body having a grain pattern. That is, in the present invention, with regard to the method for producing a plastic molded article with a grain pattern according to claims 1 to 3, the female mold of the mold used in the production method is formed of a predetermined cast steel. The grain pattern provided on the inner side of the female mold formed of the cast steel is formed by a predetermined etching means. By using such a mold, the formation of the grain pattern and the molding of the plastic molded body can be performed at the same time as in the case of the above-mentioned claim 1, and the productivity can be improved. become able to. In addition to this,
Further, according to the present invention, since the grain pattern (pattern) contributing to the formation of the grain pattern is formed by an etching means based on cast steel, a part of the form of the plastic molded body is formed. If something changes,
By removing a part of the female mold and newly applying etching means to the part, it is possible to easily cope with a design change or the like. Therefore, it is possible to respond promptly to a design change, a specification change, and the like, and it is possible to improve productivity.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. The present embodiment relates to a method for producing a plastic molded body having a grain pattern, and basically includes the following steps as shown in FIG. That is, a preheating step (A) in which a sheet-like skin material 1 having a foamed plastic material inside and a thermoplastic layer on its surface side is heated to a predetermined temperature, and the preheating step (A). The surface material 1 heated to a predetermined temperature is molded into a predetermined form, and a female pattern 9 having a predetermined grain pattern (pattern) 91 and a vacuum evacuation means 92 and an injection port 81 for injection are formed. A skin material setting step (B) of placing the preheated skin material 1 in a mold (see FIG. 4) including the male mold 8 so that the surface side thereof is on the female mold 9 side; A mold clamping step (C) for clamping the molds 9 and 8 in a state where the skin material 1 is set, and in the state where the molds are clamped in such a state, the skin is vacuumed from the female mold 9 side. Behind material 1 After performing an injection step (D) of injecting a predetermined plastic material through an injection port 81 provided in the male mold 8 on the side, and the above-described vacuuming step and injection step, the two molds 8 and 9 are molded. A mold opening step (E) of opening and taking out a molded body with a grain pattern formed in a predetermined form.

In the case of employing such a process, in the present embodiment, for example, as shown in FIG. 2, the surface material 1 is relatively easy to transfer a grain pattern as a material for forming the surface layer 11. Olefin-based elastomers (TPO) are used. A polypropylene foam material (PP foam) is used for forming the foam for the intermediate layer 12, and a material (plastic material) injected by injection molding is used for the back layer (back surface) 13. In view of the bonding property of polypropylene, a polypropylene (PP) sheet material is used. As another example of the skin material 1, as shown in FIG. 3, an olefin-based elastomer (TPO) is used for the surface layer 11 in the same manner as described above.
A polyurethane foam material is used for the mid layer 12, and further,
The back layer 13 may be made of a nonwoven fabric. In any case, plastic molding base 2
Since polypropylene (PP) with a low raw material cost is used as a material for forming
In consideration of the bonding property (weldability) with the material, for example, polypropylene (PP) or a nonwoven fabric is used.

Next, a specific example of a process for manufacturing a plastic molded body having a grain pattern using the skin material 1 having the above-described configuration will be described below. First, in the preheating step (A) shown in FIG.
Heat so that it is in the range of 70 ° C to 140 ° C. Then, in the next skin material setting step (B), the skin material 1 heated to have such a surface temperature is subjected to the female mold 9.
It is set (set) so that the surface layer 11 of the skin material 1 comes to the female die 9 side between the male die 8 and the male die 8. At this time, the molds 8 and 9 are heated so that the surface temperature has a value of about 25 ° C. to 50 ° C. As shown in FIG. 4, a grain pattern 91 having a predetermined form is formed on the inner surface of the female mold 9 by the etching means. The male die 8 is provided with an injection port 81 into which a predetermined thermoplastic material is injected at the time of injection molding.

[0012] Of the dies 8 and 9 used in the present embodiment, the female mold 9 is particularly one whose material is formed on the basis of cast steel and has a grain pattern provided on the inner surface thereof. Reference numeral 91 is formed by a predetermined etching means. by this,
In the case where the shape or the like of the present plastic molded article is partially changed, a predetermined portion of the molds 8 and 9 is cut off or a weld overlay is applied to the portion and formed in this manner. By newly applying an etching means to the surface portion, it becomes possible to respond promptly to the partial change. Generally, the pattern pattern in such a mold is formed by electroforming means. Therefore, there is a problem that the entire mold must be re-created even when a part of the shape is changed. In the case of the present embodiment, such a problem can be dealt with by partially modifying the mold by employing the above-described method.

The molds 8 and 9 in such a state are clamped in the next mold clamping step (C), and at the same time, a plurality of vacuum pumps are provided on the female mold 9 side. Through the evacuation means 92 comprising an opening hole for
The skin material 1 is sucked toward the female mold 9. At the same time, a material (thermoplastic material) forming the base 2 of the skin material 1 having the grain pattern is injected from the injection port 81 of the male mold 8 into the back surface side of the skin material 1. You. Thereby, the skin material 1 and the base 2 are integrated. At the same time, the inside of the female mold 9 is placed on the surface layer 11 provided on the surface of the skin material 1 by the suction force of the vacuum evacuation and the injection pressure of the plastic material injected from the male mold 8 side. The grain pattern 92 provided on the surface is transferred. In this way, a plastic molded body having a grain pattern on the surface is formed in the above series of steps. Further, the plastic molded body formed in this manner is taken out of both dies 8 and 9 in the next mold opening step (E). Thereby, the manufacturing process of the plastic molded body with the grain pattern is completed.

[0014]

According to the present invention, there is provided a method for producing a plastic molded article having a grain pattern on the surface, the sheet having a foamed plastic material inside and a thermoplastic layer on the surface side. A preheating step of heating the skin material to a predetermined temperature, and forming the skin material heated to a predetermined temperature in the preheating step into a predetermined form, and a predetermined grain pattern on the female mold side. And, in a mold having vacuum evacuation means, while installing so that the surface side of the preheated skin material comes to the female mold side,
In such a state, a mold clamping step of clamping the mold, and in such a clamped state, a predetermined plastic material is injected into the back side of the skin material while performing vacuum evacuation from the female mold side. Injection step, which comprises, the grain pattern provided on the surface layer can be formed simultaneously with the molding of the plastic molded body, and the efficiency of the manufacturing process of such a plastic molded body can be improved. You can now plan. That is, at the time of injection (at the time of injection) of the plastic material forming the base of the plastic molded body, the grain pattern provided on the inner surface side of the female mold is replaced with the thermoplastic plastic material forming the surface side of the skin material. As a result, the step of forming the grain pattern was shortened. As a result, the entire manufacturing process of the plastic molded body with the grain pattern is shortened, and the productivity is improved.

Further, in the present invention, with regard to a method for manufacturing a plastic molded body having a grain pattern, a female mold of a mold used in the manufacturing method is formed of a predetermined cast steel and formed of the cast steel. Since the grain pattern provided on the inner side of the female mold is formed by a predetermined etching means, if there is a change in the shape of the plastic molded body, a part of the female mold is cut off. Thus, by newly applying an etching means to the portion, it is possible to easily cope with a design change or the like. Therefore, it is possible to respond promptly to a design change, a specification change, and the like, and it is possible to improve productivity.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for producing a plastic molded body having a grain pattern according to the present invention.

FIG. 2 is a sectional view showing an embodiment of a skin material used in the present invention.

FIG. 3 is a cross-sectional view showing another embodiment of the skin material used in the present invention.

FIG. 4 is a sectional view showing a configuration of a mold used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Skin material 11 Surface layer 12 Intermediate layer 13 Back layer (back side) 2 Base 8 Male type 81 Inlet 9 Female type 91 Pattern pattern 92 Evacuation means

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (Reference) B29K 105: 04 B29K 105: 04 105: 08 105: 08 F term (Reference) 4F202 AA11 AA31 AA45 AB02 AD05 AD08 AD16 AF07 AG20 AJ03 AM28 CA11 CB01 CB13 CB20 CD24 CK11 4F206 AA11 AA31 AA45 AB02 AD05 AD08 AD16 AF07 AG20 AJ03 AM28 JA07 JB13 JB20 JF04 JF05 JL02 JN25 JN26 JQ81 4F209 AC03 AD17 AD20 AG03 AH26 PG05 PH06 PN07 P41

Claims (4)

[Claims] 1. A preheating step of heating a sheet-like skin material having a foamed plastic material inside and having a thermoplastic plastic layer on its surface side to a predetermined temperature, and a predetermined heating step in the preheating step. The surface material of the preheated skin material is formed in a mold having a predetermined grain pattern and vacuum evacuation means on the female mold side, in which the skin material heated to the temperature is molded into a predetermined form. While installing so as to come to the female mold side, a mold clamping step of clamping the mold in such a state, and in such a clamped state, while performing vacuum evacuation from the female mold side, An injection step of injecting a predetermined plastic material into the back side of the skin material, the method comprising the steps of: 2. The method for producing a plastic molded article having a grain pattern according to claim 1, wherein the surface material used in the production method has a sheet material made of an olefin-based elastomer on the surface side, and the intermediate material has an intermediate material. A foamed body made of a polypropylene foam material, and a sheet material made of a polypropylene resin on the back surface side. 3. The method for producing a plastic molded article having a grain pattern according to claim 1, wherein the surface material used in the production method has a sheet material made of an olefin-based elastomer on the surface side, and the intermediate material has an intermediate material. A foamed body made of a polyurethane foam material, and a non-woven fabric on the back surface side. 4. The method for producing a plastic molded body with a grain pattern according to claim 1, wherein a female mold of a mold used in the production method is formed of a predetermined cast steel. A mold used in a method of manufacturing a plastic molded body having a grain pattern, wherein a grain pattern provided on an inner surface side of a female mold formed of cast steel is formed by predetermined etching means.