JP3935622B2 - Blow molded product manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a molded product and a molded product, and is suitable for, for example, a synthetic resin molded product having a cured surface on the surface.
[0002]
[Prior art]
Conventionally, as a method for producing a synthetic resin molded product having a cured surface on its surface, a method of applying a coating agent to the surface of a molded product detached from a mold and curing the coating agent is known. Specifically, after a parison (molding material) made of a thermoplastic synthetic resin is blow-molded (molding process), a liquid coating agent is applied to the surface of the molded product released from the mold by spraying, dipping, or the like. The coating agent is cured by UV irradiation, heat drying or the like to form a cured surface.
Such a manufacturing method has an advantage that a cured surface can be formed on the surface even if the molded product has a complicated shape.
[0003]
[Problems to be solved by the invention]
However, since the above manufacturing method applies the coating agent to the molded product after the molding process is finished, it is manufactured from problems such as measures against adhesion of foreign matters in the transport process and measures against adhesion inside the molded product due to scattering of the coating agent, etc. The process was complicated, and it was difficult to make a series of production lines.
[0004]
Moreover, even if it manufactured with a series of production lines, since the process increased, the line became long and had the problem that the whole manufacturing system enlarged.
[0005]
Then, this invention makes it a subject to provide the manufacturing method of the molded article which can form the coating layer of a molded article in a shaping | molding process in view of the said problem.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention takes the following technical means.
That is, the method for manufacturing a molded product according to the present invention is a method for manufacturing a molded product by bringing the molding material 1 into contact with the mold surface 15 of the mold 13, and the coating agent 5 is applied to the mold surface 15 of the mold 13. After the surface is exposed, the molding material 1 is brought into contact with the mold surface 15 and the coating agent 5 is applied to the molding material 1.
[0007]
In the manufacturing method according to the present invention, the coating material 5 is applied to the molding material 1 when the molding material 1 is brought into contact with the mold surface 15 of the molding die 13 to perform molding. By allowing 5 to be dry-cured or the like, a molded product having a cured surface on the surface can be produced.
For this reason, after leaving | separating from the shaping | molding die 13, the process of apply | coating the coating agent 5 to a molded article is not necessarily required, and it has the advantage that a series of production lines can be simplified. Further, since the coating agent 5 is applied from the mold surface 15 of the mold 13, there is an advantage that the coating agent 5 can be reliably applied even to a complicated molded product.
[0008]
In the present invention, various methods can be employed for bringing the molding material 1 into contact with the mold surface 15 of the molding die 13. For example, a fluid such as air is press-fitted into the bottomed cylindrical molding material 1. A method of expanding the molding material 1 and bringing the molding material 1 into contact with the mold surface 15 can be employed.
[0009]
Furthermore, in the present invention, various methods can be used for exposing the coating agent 5 to the mold surface 15 of the mold 13. For example, the coating agent can be applied to the mold surface 15 of the mold 13 according to claim 3. A method of applying the coating agent 5 or a method of penetrating the coating agent 5 from the inside of the mold 13 into the mold surface 15 made of sintered metal as described in claim 6 can also be adopted.
[0010]
In the present invention, the material of the molding material 1 is not particularly limited, but is preferably a thermoplastic synthetic resin, more preferably a cyclic polyolefin resin, a polyolefin resin such as polyethylene or polypropylene, or a polyester resin such as polyethylene terephthalate.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
[0012]
The blow molding machine 11 according to the first embodiment includes a pair of molds 13 each having a mold surface 15 (mold surface) recessed in opposing surfaces, and the relative distance between the pair of molds 15 can be changed. The forming space 14 formed by both the mold surfaces 15 is opened and closed by contacting and separating the pair of molds 13. The mold 13 is formed with a recess 13a narrower than the mold surface 15, and the molds 13 are in contact with each other as shown in FIGS. 1 (b), 2 (a) and 2 (b). The outer surface of the mouth portion 1a of the bottomed cylindrical molding material 1 can be gripped by the concave portion 13a when contacting.
[0013]
The molding machine 11 is provided with a mouth fixture 19 capable of holding the mouth 1a of the parison 1 (molding material) from the inner surface side so as to be able to advance and retreat at a position corresponding to the recess 13a of the mold 13. Further, the mouth fixture 19 is provided with an air blowing port (not shown) so that air can be press-fitted into the held parison 1. An extension rod 21 that can be advanced and retracted to the bottom surface 15b of the mold surface 15 is housed inside the mouth fixture 19 and the extension rod 21 is fixed to the mouth as shown in FIG. The bottom portion 1b of the parison 1 held by the tool 19 and the concave portion 13a of the mold 13 is protruded so as to contact the bottom surface 15b of the mold surface 15.
[0014]
Further, as shown in FIG. 1 (a), the molding machine 11 has a spray 17 that sprays and applies the coating agent 5 on the mold surface 15 when the mold 13 is separated, and can advance and retreat to and from the opposing portion of the mold 13. In addition, the mold surface 17 is provided so as to be movable from the upper part to the lower part. In the present embodiment, a pair of sprays 17 is provided corresponding to each mold surface 15. In addition, as a coating agent, the katine hardening type alicyclic epoxy resin coating material containing a chaotic ultraviolet polymerization initiator and an alicyclic epoxy resin is employ | adopted.
[0015]
Next, a method for producing a molded product having a cured film on the outer surface using the molding machine 11 will be described.
[0016]
First, as shown in FIG. 1 (a), the molds 13 are separated from each other to open the molding space 14, and the spray 17 is made to enter, and the coating agent 5 is sprayed onto the mold surface 15 by the spray 17. Apply (application process). At this time, the pair of sprays 17 apply the coating agent 5 while moving the respective mold surfaces 15 from the upper part to the lower part (or from the lower part to the upper part). By this coating process, the coating agent 5 is exposed on the mold surface 15.
[0017]
Next, after the spray 17 is removed, the mouth fixture 19 holding the bottomed cylindrical parison 1 is inserted, and the molds 13 are brought into contact with each other as shown in FIG. The portion 14 is closed (blocking step).
Thereby, the parison 1 is held and fixed at the mouth 1a by the mouth fixture 19 and the recess 13a of the mold 13.
The parison 1 held by the mouth fixture 19 is made of a thermoplastic synthetic resin such as polyethylene terephthalate and has already been heated to a temperature suitable for stretching.
[0018]
As described above, the bottom portion 1b of the parison 1 fixed by the mouth portion 1a is stretched in the vertical direction by the protruding rod 21 as shown in FIG. 2 (a) and brought into contact with the bottom portion 13b of the mold surface 13, and then molded. A fluid such as air is pressed into the inside of the material 1 by the mouth fixture 19 to expand the parison 1 (stretched in the horizontal axis), and the outer surface of the molding material 1 is placed on the mold surface 15 as shown in FIG. (Molding process).
At this time, the coating agent 5 applied to the mold surface 15 in the application step is applied to the outer surface (contact surface) of the molding material 1.
[0019]
After cooling the blow molded product formed by biaxial stretching blow molding of the parison 1 as described above for a predetermined time, the mold 13 is opened to open the molding space 14, and the molded product is released. Then, the released molded product is transferred to a UV irradiator or a heat dryer (not shown) to cure the coating agent 5 on the outer surface of the molded product (curing step). Then, holding | maintenance of the mouth part fixing tool 19 is cancelled | released, and a series of manufacturing processes of a molded article are complete | finished.
[0020]
On the other hand, after detachment of the molded product, the spray 17 is made to enter the opened molding space 14 as shown in FIG. 1 (a) to start the coating process, and then the closing process, the molding process, and the curing process are sequentially performed. .
[0021]
A molded product having a hardened surface can be manufactured by the above-described processes, and a series of production lines is simple because a process of applying a coating agent to a molded article separated from a conventional mold is unnecessary. Have advantages.
[0022]
Further, since the coating agent 5 is applied from the mold surface 15 of the mold 13, there is an advantage that the coating agent 5 can be reliably applied to the molding material 1 even if the molded product has a complicated shape.
[0023]
In addition, since the spray 17 is provided corresponding to each mold surface 15 in the first embodiment, the application process can be speeded up. However, the application process may be performed by one spray 17, and three. It is also possible to use the above spray 17.
[0024]
Next, a second embodiment of the present invention will be described. First, the molding machine 11 in the second embodiment will be described with reference to FIG. In addition, description is abbreviate | omitted about the point which consists of the same structure as 1st embodiment.
[0025]
The blow molding machine 11 according to the second embodiment includes a pair of application members 18 each having an application surface 18 a whose shape corresponds to the mold surface 15 of the mold 13. The applicator member 18 is provided so as to be able to advance and retreat on the opposite side of the mold 13 in order to apply the coating agent 5 to the mold surface 15, and the application surface 18a is a material that can be impregnated with a liquid coating agent (for example, sponge). The coating agent 5 can be applied to the mold surface 15 by contacting the mold surface 15. Note that the molding machine 11 of the second embodiment does not have the spray 17 of the first embodiment.
[0026]
Next, a method for producing a molded product having a cured film on the outer surface using the molding machine 11 will be described.
[0027]
First, as shown in FIG. 3, the molds 13 are separated from each other to open the molding space 14, and the application member 18 is introduced into the interior, so that the application surface 18 a of the application member 18 is brought into contact with the mold surface 15. Then, the coating agent 5 is applied to the mold surface 15 (application process).
As a result, the coating agent 5 is exposed on the mold surface 15.
[0028]
Next, after the application member 18 is detached from the mold 13, similarly to the first embodiment described above, the closing process, the molding process, and the curing process are performed to release the holding of the mouth fixture 19, and the blow molded product The series of manufacturing processes is completed.
Also in the second embodiment, after the molded product is detached from the mold 13, the coating member 18 is entered into the opened molding space 14 to start the coating process, and thereafter the closing process, the molding process, and the curing process are sequentially performed. I do.
[0029]
Since a molded product having an oxidatively hardened surface can be produced by the above-described process, the advantage is that a series of production lines is simple as in the first embodiment, and the coating agent 5 is applied to the molding material 1. Has the advantage of being reliable.
[0030]
In addition, although what did not have the spray 17 in 2nd embodiment was demonstrated, it is also possible to perform an application | coating process with the spray 17 with the said application member 18. FIG.
[0031]
Next, a third embodiment of the present invention will be described. First, the molding machine 11 in the third embodiment will be described with reference to FIG. In addition, description is abbreviate | omitted about the point which consists of the same structure as 1st embodiment.
[0032]
In the molding machine 11 of the third embodiment, the mold surface 15 of the mold 13 is made of a sintered metal, and preferably an average hole of a breathable metal mold (trade name: Pocerax) manufactured by Shinto Kogyo Co., Ltd. Use diameter = 20 μm, porosity = 25%, density = 6.0-6.2 g / cm ³ .
A supply passage 12 for supplying the coating agent 5 to the mold surface 15 is formed in the mold 13. The supply passage 12 has a supply port 12a on the outer surface side of the mold 11 and a plurality of spouts 12b branched from the supply port 12a. In addition, the supply port 12a of the supply passage 12 is connected to a coating agent container (not shown) via a pump (not shown). The pump (coating agent supply means) is controlled so that the coating agent 5 penetrates and is constantly exposed to the mold surface 15.
Moreover, as a coating agent 5 suitable for infiltrating a sintered metal to be exposed on the mold surface 15, for example, a 50% weight ratio of phenylglycidyl ether as a diluent to a chaotic curable alicyclic epoxy resin paint is used. A mixture can be used, and other appropriate ones can be used.
In the third embodiment, the spray 17 of the first embodiment and the application member 18 of the second embodiment are not provided.
[0033]
Next, a method for producing a molded product having an oxide-cured film on the outer surface using the molding machine 11 will be described.
[0034]
First, in a state where the molds 13 are separated from each other and the molding space portion 14 is opened, the mouth fixture 19 holding the molding member 1 is inserted, and the molds 13 are brought into contact with each other as shown in FIG. Then, the molding space 14 is closed (clamping process).
Then, when the same molding process as in the first embodiment is performed, the coating agent 5 penetrating the sintered metal and exposed to the mold surface 15 is applied to the outer surface (contact surface) of the molding material 1. It becomes.
Hereinafter, similarly to the first embodiment, the curing process is performed, the holding of the mouth fixture 19 is released, and the series of manufacturing steps of the molded product is completed.
In the third embodiment, after removing the molded product from the mold 13, the mouth fixing tool 19 holding the molding material 1 before molding is inserted into the opened molding space portion 14 to start the closing process. Thereafter, a molding process and a curing process are sequentially performed.
[0035]
A molded product having an oxidatively hardened surface can be manufactured through the above-described processes, and a series of production lines are simple and the coating agent 5 is reliably applied to the molding material 1 as in the first and second embodiments. Has the advantage.
[0036]
Furthermore, since the coating agent 5 is infiltrated from the inside of the mold 13 and the coating agent 5 is exposed on the mold surface 15 of the mold 13, the coating process as in the first and second embodiments is not necessary. Has the advantage.
[0037]
In the third embodiment, the mold surface 15 is made of sintered metal. However, the entire mold 13 can be made of sintered metal.
[0038]
In any of the above-described embodiments, the description has been given of the case where the longitudinal axis of the parison 1 is stretched by the stretching rod 21 in the molding step, but the present invention is not limited to this, and various molding methods are adopted. can do.
[0039]
In addition, the bottomed cylindrical parison 1 has been described as an example, but the present invention is not limited to this, and various molding materials such as a bottomless cylindrical shape, a stack of two sheets, and the like. Can be adopted.
[0040]
【The invention's effect】
As described above, according to the present invention, it is possible to easily and surely manufacture a coated molded product.
[Brief description of the drawings]
1A and 1B are explanatory views of a molding machine according to a first embodiment of the present invention, where FIG. 1A is a cross-sectional view of a coating process, and FIG. 1B is a cross-sectional view of a closing process.
FIG. 2 is an explanatory view of a molding machine according to the same embodiment, in which (A) is a cross-sectional view of a state in which a molding material is vertically stretched with a stretching rod, and (B) is a diagram in which the outer surface of the molding material is brought into contact with a mold surface FIG.
FIG. 3 shows a cross-sectional view of a molding machine in a coating process in a second embodiment of the present invention.
FIG. 4 shows a cross-sectional view of a closing process in a third embodiment of the present invention.
[Explanation of symbols]
1 Molding material (Parison)
5 Coating Agent 11 Molding Machine 12 Supply Passage 13 Mold (Mold)
15 Mold surface (mold surface)
17 Spray 18 Application member

Claims (6)

In the method of manufacturing a blow molded article by bringing the molding material (1) into contact with the mold surface (15) of the mold (13) of the blow molding machine (11), the mold surface (15) of the mold (13). After the coating agent (5) is exposed, the molding material (1) is brought into contact with the mold surface (15) and the coating agent (5) is applied to the molding material (1). A method for producing a blow- molded product, wherein the coating agent (5) applied to the molding material (1) is cured after releasing the molded product from (13). The method for producing a blow- molded product according to claim 1, wherein the molded product is released after being cooled for a predetermined time, and then the coating agent (5) is cured. The blow molding according to claim 1 or 2, wherein the coating agent (5) is exposed to the mold surface (15) by applying the coating agent (5) to the mold surface (15) of the molding die (13). Product manufacturing method. The method for producing a blow- molded article according to claim 3, wherein the coating agent (5) is applied by spraying the coating agent (5) onto the mold surface (15) of the mold (13). The coating agent (5) is applied by bringing the coating member (18) having a contact surface along the mold surface shape of the mold (13) into contact with the mold surface (15) of the mold (13). The method for producing a blow molded product according to claim 3 to be performed. At least the mold surface (15) is infiltrated with the coating agent (5) from the inside of the mold (13) composed of sintered metal, and the coating agent (5) is applied to the mold surface (15) of the mold (13). The manufacturing method of the blow molded product of any one of Claims 1-5 to expose.

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