JPH05228991A - Adjusting device for temperature of preform - Google Patents

Abstract

PURPOSE:To avoid troubles in removing a preform even when the temperature of a temperature adjust means is raised, by providing a specific composite plating coat on the temperature adjust means at an area coming in contact with a cylindrical preform with a bottom for stretch blow molding, when the temperature of the preform is adjusted by being brought into contact with the temperature adjust means. CONSTITUTION:For a composite plating coat 40, a nickel coat in which fine particles of fluororesin are mixed with eutectoid dispersion is used. When temperature of a temperature adjusting pot 20 for adjusting temperature of a preform 10 is made to be a predetermined temperature by layering ring temperature adjusting blocks 22a-22e and air blows in the preform 10 so as to expand and bring into contact, the composite plating coat 40 is formed at least in the temperature adjusting block which sets the highest temperature. In the case that the contact is performed only on a part of the inner wall face of the temperature adjusting pot 20, the plating coat 40 is formed at its contact heating section. When heating is performed by inserting a temperature adjusting core into the preform 10, the plating coat 40 is formed on the temperature adjusting core.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature control device for controlling the temperature of a preform to an appropriate temperature for stretching before stretch blow molding.

[0002]

2. Description of the Related Art As molding of a synthetic resin bottle, a preform is injection-molded, and the temperature of the preform is adjusted to an appropriate stretching temperature.
A method of biaxially stretch-blow molding a preform on a vertical axis and a horizontal axis is widely known. Further, in order to secure a desired wall thickness distribution in the molded bottle, a method of forming a temperature difference in the longitudinal direction and / or the circumferential direction of the preform is adopted in the temperature control step of the preform. There is. This type of temperature control method is particularly adopted in a so-called one-stage type molding apparatus that continuously performs a preform injection molding step, a temperature control step, a biaxial stretch blow molding step, and a bottle removal step.

There are various methods for imparting a temperature distribution to the preform, but the most effective method is to provide a temperature control pot that comes into contact with the outer surface of the preform, and this temperature control pot is arranged in the longitudinal direction of the preform. It is known to be composed of a plurality of ring-shaped temperature control parts which are divided and form a temperature distribution in the vertical direction. In such a temperature control device, after arranging the preform in the temperature control pot, air is introduced into the preform to expand the preform in the radial direction and bring it into contact with the inner wall surface of the temperature control pot. If the ring-shaped temperature control section is further divided in the circumferential direction, the temperature distribution can be formed in the circumferential direction of the preform.

[0004]

As described above, in the method of controlling the temperature by bringing the outer surface of the preform into contact with the inner wall surface of the temperature control pot, the temperature control temperature is adjusted based on the characteristics of the molding resin material of the preform. There was a limit to the upper limit of. For example, in the case of polyethylene terephthalate (hereinafter abbreviated as PET), the upper limit of the temperature control temperature was about 110 ° C. When the temperature control temperature is higher than that, the preform comes into close contact with the inner wall surface of the temperature control pot, and it becomes difficult to separate the preform. That is, when the temperature control pot and the preform are relatively moved away from each other, the preform is stretched and deformed while being in close contact with the inner wall surface of the temperature control pot, or the outer surface of the preform is peeled off and the inner wall surface of the temperature control pot is separated. There was a bad effect that it adhered to.

The limitation of such controlled temperature is closely related to the stretching characteristics of the preform. For example, in the one-stage molding apparatus, the lower part of the neck of the preform is a portion that is originally difficult to be stretched because it is relatively thin, and it cannot be properly stretched unless a larger amount of heat is supplied compared to other regions. .. Therefore, in addition to contact heating with a temperature control pot, a method of inserting a heating member inside the preform in a non-contact manner and increasing the amount of heat supplied by radiant heat is adopted. However, in the case of a preform having a thick side wall, the thickness of the lower part of the neck also becomes large and the heat capacity is comparatively large, so that it is difficult to control the temperature to an appropriate stretching temperature. In this case, in order to extend the lower part of the neck to the same extent as that of the thicker side wall, the expected temperature control effect cannot be secured unless it is heated significantly. Such a problem can be solved if the upper limit of the temperature controlled temperature by contact heating can be further increased, and a device that can perform contact heating at a higher temperature controlled temperature without deformation or peeling of the preform is desired. Was there.

Therefore, an object of the present invention is to solve the above-mentioned problems, to control the temperature of a preform by contact heating at a higher temperature, and to remove the preform from the temperature control section. An object of the present invention is to provide a temperature control device that is free from deformation or peeling.

[0007]

The present invention provides a preform temperature control device having a temperature control means for contacting an outer surface or an inner surface of a bottomed cylindrical preform, wherein the temperature control means is in contact with the preform. In a region to be formed, a composite plating film layer having fine particles of fluororesin dispersed and co-deposited in a nickel film is provided.

Examples of the temperature control means for controlling the temperature by contacting the preform include a temperature control pot contacting the outer surface of the preform, or a temperature control core inserted in the preform and contacting the inner surface thereof. be able to. The temperature control pot is composed of a plurality of ring-shaped temperature control parts that are divided in the longitudinal direction of the preform and form a temperature distribution in the vertical direction. At least the highest temperature control part of the plurality of ring-shaped temperature control parts is formed. It is preferable to form the composite plating film layer on the inner wall surface of the ring-shaped temperature control part of the temperature. In case of temperature control core,
A composite plating layer may be formed on the surface of the temperature control core.

[0009]

According to the study by the present inventors, the deformation or peeling of the preform that occurs when the preform is separated from the contact heating part is more remarkable in the case where the contact heating part has a relatively high adhesiveness. We thought that it could be improved by making the heating part non-adhesive. It was confirmed that the composite plating film having the above-mentioned composition and structure is non-adhesive and is most suitable as the plating layer of the contact heating part.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

In the temperature control station shown in FIG. 1, a preform 10 made of, for example, PET resin is injection-molded.
Is a bottomed cylindrical body having an open neck portion 12, a relatively thin neck lower portion 14 therebelow, a side wall thicker than the neck lower portion 14 and having a substantially uniform thickness, and a bottom portion thinner than that. And part 16. This preform 10
Is held by the neck mold 18 and conveyed from the injection molding station in the previous step to the temperature control station.

The temperature control station has a preform 10
A temperature control pot 20 arranged around a region below the neck portion 12 and an air introduction rod 30 inserted and arranged in the neck portion 12 are arranged. The temperature control pot 20 is
A plurality of, for example, ring-shaped first to fifth temperature control blocks 22a to 22 divided into, for example, five stages in the vertical axis direction of the preform 10.
It is configured by stacking 2e. Each of the temperature control blocks 22a to 22e has a jacket 26 that circulates a temperature control medium such as hot water whose temperature is controlled in a predetermined manner. Instead of such a jacket, an electric resistance heating type heater can be adopted. Then, in the state shown in FIG. 1, by introducing air from the air introducing rod 30 into the preform 10, the preform 10 is expanded in the radial direction, and the outer surface of the preform 10 is heated to the first to fifth temperatures. The adjustment blocks 22a to 22e are brought into close contact with the inner wall surfaces. In this way, the first to the first temperature adjusted to the predetermined temperature for each zone
By the fifth temperature control blocks 22a to 22e, a desired temperature distribution is given to the preform 10 in the direction of the longitudinal axis thereof to control the temperature to an appropriate drawing temperature. In this embodiment, workability, cost,
The preform 10 has excellent heat transfer characteristics.
In view of the need to process the inner wall surface that comes into contact with the mirror surface,
The material of the temperature control block is Al.

Here, the neck lower portion 14 which has a relatively thin wall and has a low holding temperature after injection molding has a higher temperature control temperature, for example, 110 ° C. by supplying a larger amount of heat than the other regions.
It must be C or higher. Then, in this embodiment, the composite plating film layer 40 is formed on the inner wall surface of the first temperature control block 22a in which the highest temperature control temperature is set.

The composite plating film layer 40 is a nickel film in which fine particles of a fluororesin are dispersed and co-deposited. For example, Kaniflon (trade name) manufactured by Kanigen Japan Co., Ltd. can be mentioned. The composite plating film layer 40 having such a composition and structure has non-adhesiveness, weak adhesion to a resin material such as PET heated to a relatively high temperature, and good sliding. The composition of the composite plating layer 40 is preferably nickel (Ni) 80-9.
It is preferable to contain 0% by weight, 1 to 9% by weight of phosphorus (P) as a reducing agent, and 1 to 9% by weight of fluororesin (PTFE), and the particle size of the fluororesin is preferably 1 μm or less. More preferably, the content of nickel (Ni) is 83 to 86% by weight, phosphorus (P) is 7.5 to 10% by weight, and fluororesin (PTFE) is 6 to 8.5% by weight. Alternatively, it is preferable to contain 88 to 90% by weight of nickel (Ni), 8 to 9.5% by weight of phosphorus (P), and 1.5 to 3% by weight of fluororesin (PTFE). The latter is more excellent in abrasion resistance. When such a composite plated coating layer 40 is observed with a micrograph, Ni--
It is observed as a structure having a P matrix structure, in which the PTFE fine particles are dispersed almost uniformly.

The composite plating film layer 40 as described above has a first
It is formed on the inner wall surface of the temperature control block 22a with a thickness of 0.05 mm or less, for example, about 0.01 mm. Although the composite plating film layer 40 may be formed only on the inner wall surface of the first temperature control block 22a, it may be formed on the entire inner and outer surfaces of the first temperature control block 22a. It is possible to omit complicated steps such as.

More preferably, after forming the composite plating film layer 40, it may be heat-treated at a predetermined temperature. When the heat treatment is performed, the Ni-P matrix is made uniform, the structure becomes dense, and the hardness is improved. In fact, when the HV hardness was measured, the HV hardness after heat treatment was improved almost twice as compared with the hardness after plating. The heat treatment temperature is preferably 400 ° C. or lower, more preferably 300 ° C.
Can be done before and after. Since the heat treatment can be performed at such a relatively low temperature, when the temperature control block is made of an Al material, the heat treatment can be performed at a temperature much lower than its melting point. Therefore, thermal deformation of the temperature control block during heat treatment can be prevented. In addition, the composite plating film layer 40
The main composition of the is a Ni-P plated layer, and its thermal conductivity is almost the same as that of Al, which is the material of the temperature control block,
The temperature control efficiency of the preform does not decrease. Further, as in the present embodiment, the material of the temperature control block is Al,
When the composite plating film layer 40 is a Ni-P plating layer, the coefficient of thermal expansion of the base material of the mold and that of the plating layer are almost the same, and therefore the durability is also excellent. Moreover, the composite plating layer 40 is formed on the mirror-finished inner wall surface of the temperature control block.
Even if the above is formed, the surface accuracy of the coating layer 40 can be made substantially equal to the finishing accuracy of the inner wall surface.

As described above, in this embodiment, the first temperature control block 22a is set to a high temperature control temperature of, for example, 110 ° C. or higher, and the neck lower portion 14 that is difficult to stretch is heated by the direct heating method. .. At this time, the first temperature control block 22a, which has a high temperature control temperature, contacts the outer surface of the preform 10 via the non-adhesive composite plating film layer 40. Therefore, even if the preform 10 is driven to be detached from the temperature control pot, the preform 10 does not adhere to the composite plating film layer 40 serving as the inner wall surface of the first temperature control block 22a, and the preform 10 moves in the vertical axis direction. It was confirmed that it can be prevented from being stretched and deformed. Further, since the composite plating film layer 40 is non-adhesive, it was possible to solve the problem that the outer surface of the preform 10 was peeled off and adhered to the temperature control pot side. In this way, it is possible to raise the temperature control temperature in the area that is difficult to stretch as compared with the conventional method, so that the stretching characteristics of the relatively thin portion that was difficult to stretch in the past are improved, and the desired wall thickness distribution is ensured in the bottle as the final container. can do.

If the composite plating layer 40 is formed only on the first temperature control block 22a that controls the temperature of the lower neck portion 14 where peeling is particularly likely to occur, the temperature control device can be constructed without much cost increase. The invention is not limited to this, and the composite plating film layer 40 can be formed on another temperature control block as necessary. Further, the present invention is not limited to the one applied to the structure divided to form the temperature distribution in the vertical axis direction as in the above embodiment, and the one having the temperature zones divided in the circumferential direction, or You may apply to the temperature control pot which does not have such a zone division structure. Further, in the temperature control pot of the type in which only a part of the inner wall surface of the temperature control pot is brought into contact with the outer surface of the preform in terms of temperature distribution formation, the composite plating film layer 40 should be formed on the contact heating portion. You can

FIG. 2 shows an embodiment in which the present invention is applied to a temperature control device using a temperature control core.

In the figure, inside the preform 10, a temperature control core 50 having an outer shape that contacts the inner wall surface of the preform 10 is formed.
Are placed. A temperature control pot 54 for radiantly heating the preform 10 is arranged around the preform 10. The temperature control pot 54 may be zone-divided in the vertical axis direction to give a temperature distribution in the vertical axis direction. The temperature control core 50 has a jacket 52 for circulating a temperature control medium inside.
And heats the inner wall surface of the preform 10 directly. Then, the composite plating film layer 40 is formed on the surface of the temperature control core 50.

Also in this embodiment, the temperature control temperature by the temperature control core 50 can be set relatively high, and the temperature control core 50 is relatively moved in the longitudinal direction with respect to the preform 10 so as to be driven out. However, the preform 10 can be prevented from being deformed or peeled off.

The present invention is not limited to the above embodiment, but various modifications can be made within the scope of the present invention. Although the above-mentioned embodiment shows an example in which the present invention is applied to a temperature control station of a so-called one-stage molding apparatus, a so-called two-stage molding apparatus in which preform injection molding and biaxial stretch blow molding are performed in different stages. Can be similarly applied to. Here, in the two-stage system, the one in which the preform is radiantly heated by a sheath heater or the like is usually adopted, and the temperature of the preform that has been cooled is controlled while being conveyed. It is advisable to add the temperature control device according to the present invention to the subsequent stage of such a temperature control process section. In this case, even if the outer surface of the preform is heated by the temperature control step of the previous step and is in a state of easily adhering to another substance, it is brought into contact with the composite plating film layer 40 in the temperature control section of the subsequent stage. ,
No peeling will occur. Then, by adding such a temperature adjusting step, it becomes possible to impart a desired temperature distribution to the preform even with a two-stage molding apparatus. Further, the composition of the composite plating film layer 40 may be one in which fine particles of a fluororesin are dispersed and co-deposited in a nickel film, and instead of phosphorus (P) which acts as a reducing agent as in the above-mentioned embodiment. It is also possible to use other reducing agents.

[0023]

As described above, according to the present invention,
By forming a composite plating film in which fine particles of fluororesin are dispersed and co-deposited in nickel on the contact heating part, the plating film layer is non-adhesive. It is possible to prevent adverse effects such as deformation of the resin or peeling. For this reason, the upper limit of the temperature control temperature of the contact heating part can be set higher than in the past, the stretching characteristics of the region where it has been difficult to stretch in the past can be improved, and the quality of the blow-molded hollow body can be improved.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment in which the present invention is applied to a temperature control station having a contact heating type temperature control pot.

FIG. 2 is a schematic sectional view showing an embodiment in which the present invention is applied to a temperature control station having a direct heating type temperature control core.

[Explanation of symbols]

 10 Preform 12 Neck part 14 Neck lower part 16 Body part 18 Neck type 20 Temperature control pot 22a-22e Temperature control block 24,52 Jacket 30 Air introduction rod 40 Composite plating film layer 50 Temperature control core

Claims (3)

[Claims] 1. A preform temperature control device having a temperature control means for controlling the temperature by contacting an outer surface or an inner surface of a bottomed cylindrical preform, wherein the temperature control means is an area in contact with the preform. To
A temperature control device for a preform, comprising a composite plating film layer in which fine particles of fluororesin are dispersed and co-deposited in a nickel film. 2. The temperature control means according to claim 1, wherein the temperature control means is a temperature control pot that comes into contact with the outer surface of the preform, and the temperature control pot is divided in the longitudinal direction of the preform and is divided in the longitudinal direction. It is composed of a plurality of ring-shaped temperature control parts forming a temperature distribution, and the composite plating film layer is formed on at least the inner wall surface of the ring-shaped temperature control part having the highest temperature control temperature among the plurality of ring-shaped temperature control parts. A preform temperature control device characterized in that 3. The temperature control pot according to claim 1, wherein the temperature control pot is a temperature control core that is inserted into the preform and comes into contact with the inner surface thereof, and the composite plating film layer is formed on the surface of the temperature control core. A preform temperature control device characterized in that