JP2005088447A - Intermediate molded body for stretch blow molding and synthetic resin casing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intermediate molded body that prevents the occurrence of scratches that impair the fitting and sealing performance with the cap near the top surface of the stopper portion during transportation, and a synthetic resin casing molded using the intermediate molded body To do.
An intermediate molded body for a stretch blow molded body is an intermediate molded body for a stretch blow molding of a synthetic resin casing having a screw-type plug portion, and the plug portion is provided around a cylindrical wall and the periphery thereof. Including screw threads. The upper end of the cylindrical wall does not have a flat top surface portion, and its longitudinal section has an arcuate contour portion. According to this intermediate molded body, it is possible to prevent the occurrence of scratches at the upper end of the cylindrical wall during the transportation process and to provide a synthetic resin casing having no scratches on the plug portion.
[Selection] Figure 1

Description

  TECHNICAL FIELD The present invention relates to an intermediate molded body for stretch blow molding of a synthetic resin casing having a screw-type cap portion and a synthetic resin casing made by molding the intermediate molded body for stretch blow molding.

  The majority of synthetic resin enclosures sealed with caps have a threaded spigot part, and a synthetic resin liner material is used for this cap as a sealing fitting part with the enclosure spigot part. Aluminum caps are usually used. In this system, a flat part is provided on the top surface of the housing plug part in order to ensure sealing performance, and the flat part ensures adhesion with the liner material of the cap.

 Conventionally, the intermediate molded body, so-called preform molding and stretch blow molding are performed in the same factory, and it was a normal manufacturing process to transport the manufactured stretch blow molded product to the content filling factory. In recent market trends, there have been cases where production of intermediate molded bodies and stretch blow molding are performed by different companies mainly due to cost reasons. In such a case, it is necessary to transport the intermediate molded body from the company in charge of manufacturing the intermediate molded body to a company that manufactures the casing by using the intermediate molded body by stretch blow molding and fills the casing with the contents. Came to be transported in various packaging forms.

  However, it has been found that various kinds of scratches are generated between the intermediate molded bodies due to vibration during transportation. In particular, when the bottom of another intermediate molded body enters the opening of the intermediate molded body and is pressed firmly against the periphery of the opening, a large notch shape is formed at the edge corresponding to the boundary between the top surface of the stopper and the inner peripheral surface of the cylindrical wall. In the case where stretch blow molding is performed using the intermediate molded body in which such a scratch is generated, a casing having a plug portion whose fitting and sealing performance with the cap is impaired is obtained.

Conventionally, as shown in FIG. 7, on the outer periphery of the open end of the bottomed cylindrical intermediate formed body P, there are a bulging ring 22 composed of a conical surface 21a and a cylindrical surface 21b following the top surface 20, and a neck ring 23. Is used, and an intermediate molded body is used in which the upper end portion of the inner periphery of the open end portion is enlarged to form the enlarged diameter surface 24 and the stepped portion 25 (see Patent Document 1).
JP, 2002-347730, A However, the intermediate fabrication object given in this patent document 1 has prevented a crack to get to the inner peripheral surface of cut part 25, and prevented generating of the crack in the inner periphery of a top surface. It is not a thing. That is, this is because the inner cylinder of the inner plug fitting cylinder is damaged when the inner plug fitting cylinder is struck by the damage on the inner periphery of the mouth top of the casing formed by using the intermediate molded article. However, it does not prevent the occurrence of scratches to the extent that the fitting and sealing performance with the cap is impaired. As shown in FIG. 8, the intermediate molded body has, for example, 100 intermediate molded bodies P enclosed in a bag 9 having the same height as the intermediate molded body. The bags 9 are stacked and transported in the packing box 10, and the bottom of the intermediate molded body arranged above is pressed into the opening of the intermediate molded body arranged below through the cloth of the bag. It is the intermediate molding described in Patent Document 1 that when the packaged in a state is subjected to vibration during transportation or a strong load is applied to the intermediate molded body disposed below from the intermediate molded body disposed above, It cannot be prevented in products.

 An object of the present invention is to provide an intermediate molded body that prevents the occurrence of scratches that impair the fitting and sealing performance with the cap near the top surface of the cap portion during transportation, and a synthetic resin molding made using this intermediate molded body Is to provide a body.

  Invention of Claim 1 solves the subject regarding said intermediate molded object, It is an intermediate molded object for stretch blow molding of the synthetic resin casing which has a screw-type plug part, Comprising: Plug part Is an intermediate molding for stretch blow molding characterized in that it includes a cylindrical wall and a screw thread provided around the cylindrical wall, the upper end of the cylindrical wall does not have a flat top surface, and the longitudinal section has an arcuate contour. The body is the gist.

  In the intermediate molded body for stretch blow molding of the present invention, the upper end of the cylinder wall does not have a flat top surface portion, and the vertical cross section is formed in a shape having an arcuate contour portion, so intermediate molding in the transportation process The occurrence of scratches on the inside of the upper end of the plug part of the body is eliminated.

  In the present invention, the arcuate contour portion can be formed into a shape composed of two continuous arcs or a shape composed of two or more arcs connected to each other.

  Claim 4 solves the problem relating to the synthetic resin casing of the present invention. The stretch blow molding intermediate molded body according to claims 1 to 3 is attached to a blow molding die and stretch blow molded. The gist is a synthetic resin casing.

  Since the synthetic resin casing of the present invention is formed by attaching the intermediate molded body for stretch blow molding according to any one of claims 1 to 4 to a blow molding die and performing blow molding, Features no scratches.

  The intermediate molded body for stretch blow molding according to the present invention has an upper end of the cylindrical wall that does not have a flat top surface portion, and its longitudinal section is formed in a shape having an arcuate contour portion. The open end of the intermediate molded body is prevented from being damaged by impact, load, etc., and as a result, according to the stretch blow molded intermediate molded body of the present invention, the plug portion is scratched. It is possible to provide a synthetic resin casing without any problem.

  FIG. 1 is a partial sectional view of a cylindrical wall of an intermediate molded body for stretch blow molding according to a first embodiment of the intermediate molded body for stretch blow molding according to the present invention, and FIG. 2 is an intermediate molded body for stretch blow molding according to the present invention. It is a partial cross section figure of the cylinder wall of the intermediate molded object for stretch blow molding of 2nd Embodiment. FIG. 3 is a partial sectional view of a cylindrical wall of a conventional intermediate body for stretch blow molding. FIG. 4 is a cross-sectional view showing a part of a plug portion of a synthetic resin casing formed by using the stretch blow molding intermediate molded body shown in FIG. FIG. 5 is a cross-sectional view showing a part of a plug portion of a synthetic resin casing formed by using the stretch blow molding intermediate molded body shown in FIG. 6 is a cross-sectional view showing a state in which a cap is attached to the plug portion of the synthetic resin casing shown in FIG.

  The intermediate molded body for stretch blow molding is a bottomed cylindrical stretch blow molded intermediate molded body having a screw-type plug portion, and the open end portion that forms the housing opening of the intermediate molded body is a cylinder. Including the wall 1 and the screw thread 2 provided on the outer periphery thereof, the cylindrical wall upper end 3 does not have a flat top surface portion, and its longitudinal section has an arcuate contour portion. FIG. 1 shows a first embodiment of an intermediate molded body, in which a longitudinal cross section of an upper end 3 of a cylindrical wall is an arc having a radius R1 (an arc positioned outside the cylindrical wall 1) and an arc having a radius R2 continuous thereto (cylindrical wall) 1 has an arcuate contour portion formed of an arc located on the inner side of 1. Here, R1 = R2 or R2> R1. The entire open end portion forming the housing opening having the above-described structure is whitened by thermal crystallization.

  FIG. 2 shows a second embodiment of the intermediate molded body, and the longitudinal cross section of the upper end 3 of the cylindrical wall has two arcs of radius R2 (arcs located outside and inside the cylindrical wall 1) and the two arcs described above. Three circular arcs of radius R3 located between them have arc-shaped contours that are continuous with each other. The entire open end that forms the casing opening having the above-described structure is whitened by thermal crystallization in the same manner as the intermediate molded body shown in FIG.

  As a molding material for the intermediate molded body, polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, or the like can be applied.

  As shown in FIGS. 1 and 2, by increasing the radius of the arc located on the inner peripheral side of the upper end 3 of the cylinder wall, an impact and a load are applied to the inner side of the cylinder wall 1 during the transportation process of the intermediate molded body. It is possible to prevent the open end from being damaged. In addition, since the outer peripheral side of the cylindrical wall upper end 3 is also formed in a circular arc shape, the occurrence of scratches on the outer peripheral side of the cylindrical wall upper end 3 due to the collision between the intermediate molded bodies can be prevented.

  FIG. 3 shows a conventional intermediate molded body. This intermediate molded body has a flat top surface 5 at the upper end 3 of the cylindrical wall. Further, although a curved surface is formed between the top surface 5 and the circumferential surface of the cylindrical wall 1, the arc radii R1 and R2 are not large.

  FIG. 4 shows a part of the plug portion of the synthetic resin casing formed by using the stretch blow molding intermediate molded body shown in FIG. FIG. 5 shows a part of a plug portion of a synthetic resin casing formed by using the stretch blow molding intermediate molded body shown in FIG. The plug portion of the synthetic resin casing includes a cylindrical wall 11 and a screw thread 12 provided outside thereof, the cylindrical wall upper end 13 does not have a flat top surface portion, and the longitudinal section thereof has an arcuate contour portion. Have 4 shows a part of the plug portion of the synthetic resin casing formed by using the intermediate molded body shown in FIG. 1, and the vertical cross section of the upper end 13 of the cylindrical wall is an arc having a radius R1 (the outer side of the cylindrical wall 11). And an arcuate contour composed of an arc having a radius R2 continuous to the arc (an arc located inside the cylindrical wall 11). Here, R1 = R2 or R2> R1.

  FIG. 5 shows a part of a plug portion of a synthetic resin casing formed by using the intermediate molded body shown in FIG. 2, and the vertical cross section of the upper end 13 of the cylinder wall is an arc having two radii R2 (the cylinder wall 11). Arcs located on the outside and inside of the arc) and three arcs having a radius R3 located between the two arcs described above have arcuate contours that are continuous with each other. The entire open end portion forming the housing opening having the above-described structure is whitened by thermal crystallization.

  The synthetic resin casing of the present invention is formed by blow molding using an intermediate molded body made of polyethylene terephthalate, polyethylene, polypropylene, polycarbonate, etc., and particularly polyethylene terephthalate is made of water vapor, oxygen, odor, ultraviolet rays, etc. It is suitable because it is excellent in anti-permeability. Alternatively, an in-mold label forming label may be attached to the blow mold, the in-mold label forming may be performed, and the housing having the in-mold label on the outside of the housing.

  FIG. 6 shows a state in which a cap is attached to the plug portion of the synthetic resin casing shown in FIG. As shown in this figure, the outer ring 6 of the cap 5 is in contact with a circular arc located outside the upper end 13 of the cylindrical wall or a portion of the cylindrical wall 11 continuing to the circular arc, and the contact ring 7 is near the top of the upper end 13 of the cylindrical wall. The inner ring 8 is in contact with an arc located inside the upper end 13 of the cylinder wall or in contact with the cylinder wall continuous with the arc, whereby the plug portion is sealed. Since the synthetic resin casing of the present invention has no flaws on the top surface of the cap portion, the fitting and sealing performance with the cap is good.

  Next, the present invention will be specifically described with reference to examples and comparative examples.

  As shown in FIG. 1, the open end that forms the housing opening includes a cylindrical wall 1 and a screw thread 2 provided on the outer periphery thereof, and the cylindrical wall upper end 3 does not have a flat top surface, The vertical cross section has an arcuate contour, and the vertical cross section of the upper end 3 of the cylindrical wall is an arc having a radius R1 (an arc positioned outside the cylindrical wall 1) and an arc having a radius R2 continuous thereto (inside the cylindrical wall 1). A bottomed cylindrical intermediate molded body having an arcuate contour portion made of a circular arc located at R1 = 1.0 mm and R2 = 1.0 mm was manufactured by injection-molding polyethylene terephthalate resin.

  100 pieces of each of the produced intermediate molded bodies sealed in a bag having the same height are placed in a packing box in a stacked state and transported after sealing, and the impact on the top of the mouth of the intermediate molded body, The presence or absence of scratches due to load or the like and the number of intermediate molded bodies with scratches were examined. As a result, it was found that there were no scratched intermediate molded bodies.

  As shown in FIG. 2, the open end that forms the housing opening includes a cylindrical wall 1 and a screw thread 2 provided on the outer periphery thereof, and the cylindrical wall upper end 3 does not have a flat top surface portion. The vertical cross section has an arcuate contour, and the vertical cross section of the cylindrical wall upper end 3 is located between two circular arcs having a radius R2 (arcs positioned outside and inside the cylindrical wall 11) and the two circular arcs. A bottomed cylindrical intermediate molded body having an arcuate contour in which three arcs of radius R3 are continuous with each other and R2 = 0.8 mm and R3 = 3.0 mm was molded by an injection molding method.

  The molded intermediate molded body sealed in 100 bags in the same height is put in a packing box in a stacked state and transported after sealing, the impact on the top of the mouth of the intermediate molded body, The presence or absence of scratches due to load or the like and the number of intermediate molded bodies with scratches were examined. As a result, it was found that there was no scratched intermediate molded body.

[Comparative example]
Example 1 with respect to the conventional intermediate molded body (R1 = 0.5 mm, R2 = 0.5 mm, the length of the flat surface between both arcs along the radial direction of the cylindrical wall = 1.0 mm) shown in FIG. The same transportation test as in No. 2 was performed, and the presence or absence of scratches due to impact, load, etc. on the top of the mouth of the intermediate molded body and the number of scratched intermediate molded bodies were examined. As a result, it was found that there were as many as 18/100 intermediate molded bodies with scratches.

  The intermediate molded body for stretch blow molding according to the present invention has an upper end of the cylindrical wall that does not have a flat top surface portion, and its longitudinal section is formed in a shape having an arcuate contour portion. The open end of the intermediate molded body is prevented from being damaged by impact, load, etc., and as a result, according to the stretch blow molded intermediate molded body of the present invention, the plug portion is scratched. Therefore, the present invention can be applied to various uses such as a packaging housing and a beverage packaging housing.

It is a fragmentary sectional view of 1st Embodiment of the intermediate molded object for stretch blow molding of this invention. It is a fragmentary sectional view of 2nd Embodiment of the intermediate molded object for stretch blow molding of this invention. It is a conventional intermediate molded body for stretch blow molding. It is a fragmentary sectional view which shows a part of plug part of the synthetic resin casing formed using the intermediate molded body for stretch blow molding of the first embodiment of the intermediate molded body for stretch blow molding of the present invention. It is a fragmentary sectional view which shows a part of spout part of the synthetic resin casing which uses the intermediate | middle molded object for stretch blow molding of 2nd Embodiment of the intermediate molded object for stretch blow molding of this invention. It is sectional drawing which shows the state which attached the cap to the longitudinal cross-section of the synthetic resin casing of this invention. It is a side view of an example of the conventional intermediate molded object. It is the schematic which shows the packing state of an intermediate molded object.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cylindrical wall of intermediate molded body 2 Screw thread of intermediate molded body 3 Upper end of cylindrical wall of intermediate molded body R1, R2, R3 Arc radius 4 Top surface of conventional intermediate molded body 5 Cap 6 Outer ring 7 Contact ring 8 Inner ring P Intermediate molded body 9 Bag 10 Packing box 11 Cylindrical wall of plug portion of synthetic resin casing 12 Screw thread of synthetic resin casing 13 Upper end of cylindrical wall 20 Top surface of intermediate molded body 21a Conical surface 21b Cylindrical surface 22 Enlarged ring 23 Neck ring 24 Expanded surface 25 Step

Claims (4)

  An intermediate molded body for stretch blow molding of a synthetic resin casing having a screw-type plug part, the plug part including a cylindrical wall and a screw thread provided around the cylindrical wall, and the upper end of the cylindrical wall is a flat ceiling An intermediate molded body for stretch blow molding, which has no surface portion and has a longitudinal cross section having an arcuate contour portion.   The intermediate molded body for stretch blow molding according to claim 1, wherein the arcuate contour portion is composed of two continuous arcs.   The intermediate molded body for stretch blow molding according to claim 1, wherein the arcuate contour portion is composed of two or more arcs that are continuous with each other. A synthetic resin casing made by stretching the blow-molded intermediate molded body according to any one of claims 1 to 3 on a blow-molding mold and stretching and molding.