PREFORM

Abstract

A preform for use in molding a bottle by blow molding includes a tubular sprout portion and a bottomed tubular preform body. The preform has a weight ranging from 82 to 90 g. The maximum wall thickness of the preform body ranges from 4.5 to 5.0 mm. The preform has a total length ranging from 165 to 175 mm.

Claims

1. A preform for use in molding a bottle by blow molding, comprising: a tubular sprout portion and a bottomed tubular preform body; wherein the preform has a weight ranging from 82 to 90 g; the maximum wall thickness of the preform body ranges from 4.5 to 5.0 mm; and the preform has a total length ranging from 165 to 175 mm.

2. The preform of claim 1, wherein: a joint portion of the preform body to the spout portion comprises a tapered portion whose wall thickness progressively increases as it extends away from the spout portion; and the tapered portion has a straight outer circumferential face and a tapered inner circumferential face.

3. The preform of claim 2, wherein the tapered portion has length ranging from 4 to 12 mm.

4. The preform of claim 1, wherein the preform is configured to be used for molding a bottle in which a ratio of a length of a body portion relative to the total length of the bottle ranges from 0.30 to 0.50.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG. 1 is a section view of a preform,

[0019] FIG. 2 is a front view showing an example of a bottle molded from a preform relating to an embodiment, and

[0020] FIG. 3 is a view illustrating blow molding steps.

EMBODIMENT

[0021] Next, an embodiment of a preform relating to this disclosure will be explained with reference to the accompanying drawings. A preform 1 relating to the instant embodiment is for use in molding a bottle 2 exemplified by one shown in FIG. 2 by the blow molding technique. The preform 1 as a whole presents a test-tube like shape and is made mainly of a thermosetting resin such as polyethylene, polypropylene, polyethyleneterephthalate, etc.

[0022] Moreover, as shown in FIG. 3, a bottle 2 having a desired shape can be obtained from this preform 1 by carrying out a series of blow molding steps. Namely, the preform 1 is heated to an appropriate temperature by a heater 3 (FIG. 3 (a)), this hot preform 1 is set in a mold 4 (FIG. 3 (b)). Then, the preform 1 is stretched in the vertical direction by a stretching rod 5 (FIG. 3 (c)), then, an amount of high-pressure air is blown into the preform 1 to blow it out into the shape of the bottle 2 (FIG. 3 (d)) and the bottle 2 after being cooled is removed (FIG. 3 (e)).

[0023] In the case where the bottle 2 to be molded has a large capacity, it becomes necessary to blow the preform 1 correspondingly larger. Thus, the weight of the preform 1 needs to be increased correspondingly by e.g. increasing the wall thickness of the preform 1. However, increased weight results in increase in the wall thickness, which in turn leads to necessity of a longer time for heating the preform 1 to an appropriate temperature. To cope with this, the preform 1 relating to the instant embodiment is configured such that the preform 1 can be heated in an efficient manner even when the bottle 2 to be molded has a large capacity. Therefore, with using a standard blow molding device, it is still possible to carry out the above-described series of blow molding steps and the contents filling step in conjunction and synchronism with each other, thus making simplification of the plant operation possible. Next, the preform 1 relating to the instant embodiment will be explained specifically.

[0024] The preform 1 relating to the instant embodiment includes a tubular spout portion 11 and a bottomed tubular preform body 12. The preform 1 is configured such that its weight ranges from 82 to 90 g, the maximum wall thickness of the preform body 12 ranges from 4.5 to 5.0 mm, and the total length ranges from 165 to 175 mm. With the above balance setting among the weight, the wall thickness and the total length, even when the bottle to be molded has a large capacity, it is still possible to heat the preform in an efficient manner.

[0025] Specifically, the preform 1 can be heated efficiently to the inner side thereof with using a standard blow molding device capable of heating the preform 1 to from 95 to 120 C.

[0026] The joint portion of the preform body 12 to the spout portion 11 is constituted of a tapered portion 13 whose wall thickness progressively increases as it extends away from the spout portion 11. In the tapered portion 13, its outer circumferential face is formed straight and its inner circumferential face is tapered. With this arrangement of forming the outer circumferential face of the joint portion of the preform body 12 to the spout portion 11 straight and forming its inner circumferential face tapered, the portion which is to form a neck portion 22 and a shoulder portion (continuous from the neck portion 22 and has a diameter that progressively increases toward the lower side) 23 can be lightened easily, so that the total weight of the preform 1 can be suppressed correspondingly. As a result, the wall thickness can be suppressed, which in turn makes it possible to heat the preform even more efficiently.

[0027] Further, the length of the tapered portion 13 is set to range from 4 to 12 mm. With this setting of the length of the tapered portion 13 from 4 to 12 mm, the portion which is to form the neck portion 22 and the shoulder portion 23 after the molding of the bottle 2 can be lightened even more easily.

[0028] In addition, with the preform 1 having the above-described balance setting of the weight, the wall thickness and the total length, it is possible to suitably form the bottle 2 having a shape similar to a glass bottle to be used for filling a beverage, e.g. hard liquor such as whisky, wine, etc., therein, such as the one shown in FIG. 2. More particularly, such bottle having a relatively long neck portion continuous from the spout portion (denoted with numeral 21 in the bottle shown in FIG. 2) can be suitably molded which has e.g. an approximately straight body type or a tubular neck portion (denoted with numeral 22 in the case of the bottle shown in FIG. 2) having a diameter progressively increased toward the lower side and the height-wise length of this neck portion is substantially equal to or longer than the height-wise length of the shoulder portion (denoted with numeral 23 in the bottle shown in FIG. 2).

[0029] Further, as for some preferred conditions of the bottle to be molded by the preform 1 of the instant embodiment, its capacity ranges from 1.5 to 4.0 liters and more preferably from 1.5 to 3.0 liters, and especially preferably ranges at 1.75-0.10 liters. Further, the ratio of the length of the body portion (denoted with numeral 24 in the bottle shown in FIG. 2) relative to the total length of the bottle ranges preferably from 0.30 to 0.50, more preferably from 0.30 to 0.45 and especially preferably from 0.33 to 0.41. Further, the total length of the bottle ranges preferably from 300 to 400 millimeters.

[0030] Incidentally, the shape of the preform 1 of the instant embodiment, the shape/capacity of the resin bottle molded by the preform 1 are not particularly limited. Further, the liquid to be charged and filled in the resin-made bottle is not particularly limited. As some non-limiting examples thereof, drinking water, carbonated beverage, tea, juice, coffee, cocoa, soft drink, alcoholic drink, milk-based drink, or liquid food such as soup, and liquid condiment such as Worcester sauce, soy sauce can be cited.

INDUSTRIAL APPLICABILITY

[0031] The present disclosure can be applicable to a preform for use in molding a bottle to be filled with e.g. a liquid.

DESCRIPTION OF SIGNS

[0032] 1: preform [0033] 11: spout portion [0034] 12: preform body [0035] 13: tapered portion [0036] 2: bottle