JP2009286457A - Stretch blow molded container and its molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for stretch blow molding capable of intentionally forming a thin wall part at a predetermined position part of a bottom wall of a bottle-shaped container, and to provide a spouting container capable of using up a content liquid to the end without worry about the attitude or the like of the container. <P>SOLUTION: On a preform in which a thickness deviation part with a relatively thick wall or thin wall condition is formed at a predetermined position part of a bottom wall, by utilizing a difference of cooling or heating speed in a temperature adjusting step of adjusting the temperature to a suitable temperature for an injection molding step or stretch blowing step, a high temperature spot is formed in the thickness deviation part. By utilizing a deviated stretch property of this high temperature spot, the high temperature spot is stretched and deformed into a relatively thin wall. Thereby, the thickness of the bottom wall of the bottle-shaped container is convergently thinned toward the predetermined position part, and the inner face of the bottom wall is molded so as to be inclined downward convergently. An accumulating spot into which the content liquid remaining near the inner face of the bottom wall flows and accumulates convergently is formed in the vicinity of this predetermined position part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bottle-type stretch blow-molded container having a relatively thick bottom wall, and a method for molding the same, which is used by assembling a pouring pump having a suction pipe for sucking the liquid content downward. About.

For example, Patent Document 1 discloses a small bottle-shaped container made of polyethylene terephthalate (hereinafter referred to as PET) resin by stretch blow molding, which is used with a pouring pump for pouring the content liquid into the mouth tube portion. The idea concerning is described.
FIG. 10 shows a typical example of a small bottle-type container by this type of conventional stretch blow molding. The container 101 has a cylindrical body portion 103, and a pumping pump 21 for pouring the liquid content is attached to the mouth tube portion, and a suction pipe 23 is connected to the bottom wall of the bottom portion 104 from the lower end of the pump. 105 extends near the inner surface.

Here, what is characteristic of this type of small container is that the bottom wall 105 is thick, and the container is grounded at the peripheral edge of the bottom wall 105 to ensure the self-supporting property of the container. According to the law, the thickness of the central portion of the bottom wall 105 is increased, and the thickness is diverged from the central portion toward the peripheral portion.
For this reason, the liquid Lq remains on the periphery of the bottom wall 105 immediately before the content liquid Lq is used up.
Japanese Utility Model Publication No. 3-29416

  However, in this type of pouring container, when pouring, the tip of the pouring nozzle 21 is tilted so that the tip of the pouring nozzle 21 is directed obliquely downward from the upright position, and the content liquid is used up as much as possible. The suction pipe 23 must be adjusted and used so that the tip of the suction pipe 23 is at the peripheral edge of the bottom wall 105 and in the same direction as the direction of the pouring nozzle 22. Difficult, inevitably much liquid cannot be used up and remains.

  In the stretch blow molding of a bottle-type container, the present invention intentionally forms a thin-walled portion at a predetermined position on the bottom wall, and uses this thin-walled portion to fix the position of the tip of the suction pipe. A bottle type that is intended to form an accumulation spot that can be effectively accumulated, so that the user can use up the content liquid almost completely without worrying about the direction of the dispensing nozzle. The purpose is to provide a container.

Here, the stretch blow molding method of the present invention will be described first, and then the stretch blow molded container of the present invention that can be molded by this molding method will be described.
Among the means for solving the problems of the present invention, the main method relating to the stretch blow molding method of a synthetic resin bottle-shaped container is:
A test tube in which a wall thickness is formed on the bottom wall at a predetermined position on the bottom wall so that the wall thickness is thicker or thinner than the wall thickness of the bottom wall excluding the predetermined position. Injection molding the preform,
By utilizing the difference in cooling or heating rate in the temperature adjustment process for adjusting the injection molding process or the preform to a temperature suitable for the stretch blow process, depending on the uneven thickness state of the uneven thickness part, Compared to the temperature of the part of the wall excluding this uneven thickness part, a high temperature spot that is partially hot is formed,
Next, in the stretch blow step, the high temperature spot is stretched and deformed to a relatively thin wall using the uneven stretch property of the hot spot on the bottom wall,
By extending and deforming the high temperature spot, the thickness of the bottom wall of the bottle-shaped container is reduced in a convergent shape toward the predetermined position portion, so that the inner surface of the bottom wall is converged downward toward the predetermined position portion. Inclined and molded
In the vicinity of the predetermined position portion, an accumulation spot in which the content liquid remaining in the vicinity of the inner surface of the bottom wall flows and accumulates in a convergent shape is formed.
It is said.

The basic idea of the stretch blow molding method is to intentionally form an uneven thickness portion that is a relatively thick or thin portion on the bottom wall of the preform to be used,
By utilizing the difference in cooling or heating rate in the temperature adjustment process for adjusting the injection molding process or preform to a temperature suitable for the stretch blow process, due to the uneven thickness state of the uneven thickness part, A high-temperature spot that is partially hot compared to the temperature of the portion excluding this uneven thickness portion is formed, and the partial stretchability of this high-temperature spot, that is, partially stretched to a higher magnification than other portions. It is said that the predetermined position portion of the bottom wall of the bottle-shaped container to be molded is thinned by utilizing the above properties.

  And the thickness of the bottom part of the bottle-shaped container to be formed by stretch blow molding a preform having a high temperature spot formed by utilizing the difference in cooling or heating speed by the uneven thickness part at a predetermined position part of the bottom wall Can be thinned in a converging shape toward a predetermined position on the bottom wall, and the inner surface of the bottom wall is inclined downward in a converging shape toward the predetermined position as the converging-shaped thinning occurs. It is possible to form an accumulation spot in which the liquid content remaining near the inner surface of the bottom wall flows and accumulates in a convergent shape near the predetermined position.

Another method of the present invention is the above main method,
The molding method is based on the hot parison method, and the uneven thickness portion of the bottom wall of the preform is injection-molded to a relatively thick wall, and the difference in cooling rate in the injection mold due to the uneven thickness state of this uneven thickness portion is determined. It is said that a high temperature spot is formed in the uneven thickness portion.

Here, there are two methods of stretch blow molding, the so-called cold parison method and hot parison method.
Among them, the hot parison method is also called a one-stage method, in which an injection-molded preform is taken out without being sufficiently cooled and stretch blow-molded using the retained heat, and the preform taken out from the mold is temperature-controlled. It is adjusted to a temperature suitable for stretch blow molding in the pot.

  Here, in the cooling process in the injection mold, the cooling rate of the thick uneven portion is slowed down, and a hot spot is formed in the uneven portion, particularly in the central portion in the thickness direction. Is to take out the preform that has been injection-molded as described above without sufficiently cooling, and to perform stretch-blow molding using the retained heat. In the stretch-blow process, it is formed in the injection mold as described above. The high temperature spot can be stretched and deformed to a relatively thin wall.

Still another method of the present invention is the above main method,
The molding method is the cold parison method,
The preform thickness of the bottom wall of the preform is injection molded to a relatively thin wall, and the preform taken out with the injection mold is temporarily stored at room temperature.
The temperature adjustment process shall be adjusted to a temperature suitable for the stretch blow process by heating the preform with a heating device,
When adjusting the temperature by the heating, a high-temperature spot is formed in the uneven thickness part by utilizing the difference in the heating rate due to the thickness.
It is said.

The cold parison method is also called a two-stage method, and after cooling an injection-molded preform, it is temporarily stocked and heated again using a heating means such as an infrared heater to adjust it to a temperature suitable for stretch blow molding and stretching. A blow molding method,
In the uneven thickness part formed thinly, a heating rate is quick, and a high temperature spot can be formed in an uneven thickness part using the difference in a heating rate with the part except an uneven thickness part.

  According to still another method of the present invention, a predetermined position portion of the bottom wall of the preform is set as a predetermined center angle position portion of a peripheral portion of the bottom wall, and a predetermined position portion of the bottom wall of the container is set as a position of the bottom wall of the container. This is a method for forming an accumulation spot at a predetermined central angular position portion of the peripheral portion of the bottom wall of the bottle-shaped container.

  Still another method of the present invention is the above-described method, wherein the vertical band-shaped vertical wall thickness portion in which the wall thickness is thick or thin in the vertical direction from the body portion to the bottom portion of the preform at a predetermined center angle position is provided. And forming the uneven thickness portion at a predetermined center angle position portion of the peripheral edge portion of the bottom wall by the vertical uneven thickness portion, and thus forming the vertical uneven thickness portion to form the peripheral edge of the bottom wall. An uneven thickness part can also be formed in the predetermined center angle position part of a part.

  According to still another method of the present invention, the predetermined position portion of the bottom wall of the preform is the central portion of the bottom wall, and the predetermined position portion of the bottom wall of the container is the central portion of the bottom wall of the container. This is a method for forming an accumulation spot at the center of the bottom wall of a bottle-type container.

  Next, the stretch blow molded container of the present invention will be described. These stretch blow molded containers can be molded by the above-described stretch blow molded method of the present invention.

Of the means for solving the problems of the present invention, the main configuration relating to a bottle-shaped stretch blow molded container made of synthetic resin is:
The thickness of the bottom wall of the bottom portion is formed in such a manner that the inner surface of the bottom wall is inclined downward in a convergent shape toward the predetermined position portion by thinning the wall thickness toward the predetermined position portion of the bottom wall. ,
In the vicinity of the predetermined position portion, an accumulation spot in which the content liquid remaining in the vicinity of the inner surface of the bottom wall flows and accumulates in a convergent shape is formed.
It is said.

  As the wall thickness of the bottom is reduced toward the predetermined position of the bottom wall in a convergent manner, the inner surface of the bottom wall is inclined downward toward the predetermined position so as to converge near the predetermined position. In addition, it is possible to form an accumulation spot where the content liquid remaining in the vicinity of the inner surface of the bottom wall flows and accumulates in a convergent shape. In other words, the content liquid remaining in the vicinity of the inner surface of the bottom wall flows along the inclined surface formed in a convergent shape on the inner surface of the bottom wall and is accumulated in the accumulation spot.

  And this predetermined position part is the part which became concavely low on the upper surface of the bottom wall, and the tip position of this suction pipe is stabilized by holding the tip of the suction pipe of the pumping pump in this part. And can be held.

  Another configuration of the present invention is that, in the main configuration described above, the predetermined position portion is a predetermined center angle position portion of the peripheral portion of the bottom wall.

In the above configuration, the accumulation spot is formed in the vicinity of the predetermined center angle position portion of the peripheral portion of the bottom wall.
Here, when the dispensing pump is attached to the mouth tube portion and used as a dispensing container, the tip of the suction pipe is further locked to the collecting spot so that the direction of the collecting spot coincides with the direction of the dispensing nozzle. When the container is used in an inclined position with the tip of the nozzle directed obliquely downward during the pouring operation, the residual liquid naturally accumulates in this accumulation spot. Therefore, the user can use up the content liquid almost to the end without any particular concern.

  Still another configuration of the present invention is that, in the above main configuration, the predetermined position portion is the central portion of the bottom wall.

In the above configuration, the accumulation spot is formed near the center of the bottom wall.
The bottom wall of the bottle-type container by the conventional stretch blow molding method shown in FIG. 10 has a thickened central portion, and has a shape diverging from the central portion toward the peripheral portion. According to the molding method of the invention, the shape can be reduced to a convergent shape from the peripheral part to the central part, as in the above configuration.

  And when attaching the pump to the mouth tube part and using it as a dispensing container, the tip of the suction pipe is held in a locking shape at the collecting spot formed in this central part, and the accumulated residual liquid is It can be used up to the end efficiently.

  Still another configuration of the present invention is that when a dispensing pump in which a suction pipe for sucking up the content liquid is attached to the mouth tube portion is assembled and used as a dispensing container, As described above, the direction of the dispensing nozzle and the direction of arrangement of the collecting spot can be matched in advance, and the tip of the suction pipe can be held in a locked state on this collecting spot, especially with special adjustment by the user Thus, it is possible to provide a pouring container that can use up the content liquid almost completely without being carried out.

Since the present invention has the above-described method and configuration, the following effects can be obtained.
In the main method according to the stretch blow molding of the present invention,
By intentionally forming an uneven thickness part that is a relatively thick or thin part on the bottom wall of the preform to be used, the injection molding process or preform according to the uneven thickness state of the uneven thickness part is used as a stretch blow process. Using the difference in cooling or heating rate in the temperature adjustment process to adjust to a suitable temperature, the high temperature that is partially higher than the temperature of the portion of the bottom wall excluding this uneven thickness portion in the uneven thickness portion A spot is formed, and the predetermined position portion of the bottom wall of the bottle-shaped container to be molded is formed by utilizing the partial stretchability of this high-temperature spot, that is, the property of being partially stretched at a higher magnification than other portions. Can be thinned.

In what has the main composition concerning the stretch blow container of the present invention,
As the wall thickness of the bottom is reduced toward the predetermined position of the bottom wall in a convergent manner, the inner surface of the bottom wall is inclined downward toward the predetermined position so as to converge near the predetermined position. In addition, it is possible to form an accumulation spot where the content liquid remaining in the vicinity of the inner surface of the bottom wall flows and accumulates in a convergent shape.

  And this accumulation spot is a concavely lowered portion on the upper surface of the bottom wall, and by holding the tip of the suction pipe of the pouring pump used by being attached to the mouth tube portion in this shape, The tip position of the suction pipe can be held stably, and the direction of the pumping nozzle of the pumping pump and the position of the accumulation spot can be matched in advance. The liquid content can be used up.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below along the examples with reference to the drawings.
1 to 3 illustrate a first embodiment of the stretch blow molded container of the present invention. FIG. 1 is a partially longitudinal side view, FIG. 2 is a bottom view, and FIG. 3 is a perspective view near the bottom. .
In FIG. 3, hatching is added to represent the thickness distribution of the bottom wall 5 or the inclined form of the inner surface of the bottom wall 5.
This container 1 is a small bottle-type container made of PET resin by stretch blow molding, and has a mouth tube part 2, a cylindrical body part 3, and a bottom part 4.

The average thickness of the bottom wall 5 of the bottom part 4 is relatively thick, about 6 mm.
This embodiment is an example in which the predetermined position portion 6 is a predetermined center angle position portion 6a of the peripheral edge of the bottom wall 5, and the bottom wall 5 is thinned in a convergent shape toward the predetermined center angle position portion 6a. (Refer to FIGS. 1 and 3), the inner surface (upper surface) of the bottom wall 5 is inclined obliquely downward toward the central angular position portion 6a due to this thinning, and in the vicinity of the central angular position portion 6a. Then, the content liquid Lq remaining in the vicinity of the inner surface of the bottom 5 flows and accumulates along this inclined surface (see the arrow indicated by the two-dot chain line in FIG. 3), and an accumulation spot 7 is formed.

  Here, as shown by a two-dot chain line in FIG. 1, when the dispensing pump 21 is attached to the mouth tube portion 2 of the container 1 and used as a dispensing container, when the content liquid is filled, that is, the product If the direction of the dispensing nozzle 22 and the arrangement direction of the accumulation spot 7 are matched in advance in the shipping state, and the tip of the suction pipe 23 is held in the accumulation spot 7 in a locked state, it is in use. Further, the tip position of the suction pipe 23 is not shifted.

  For this reason, when a small amount of the content liquid Lq remains in the vicinity of the inner surface of the bottom portion 5, it remains even if the container 1 is held in an upright position or the pouring nozzle 22 is held in an inclined position inclined downward. Since the content liquid Lq is naturally collected in a fluidized state at the accumulation spot 7 along the slope of the bottom wall 5 that converges in a convergent manner, the content liquid is poured out almost completely to the end without any particular concern. be able to.

Next, a stretch blow molding method for forming an inclined surface inclined in a convergent shape toward the container 1 of the first embodiment, particularly the central angular position portion 6a of the bottom wall 5, will be described.
The container 1 of this example is based on the hot parison method. First, in the injection molding process, the test tubular preform 11 shown in FIG. 5 is molded, and then the preform 11 is heated from the injection mold. 9 and inserted in the temperature control pot 31 shown in the schematic explanatory diagram of FIG. 9 while maintaining this temperature, and the preform 11 is heated in the temperature control pot 31 to a temperature suitable for the next stretch blow step. Next, stretch blow molding is performed to the size of the container 1 represented by a two-dot chain line in FIG. 5 with a stretch blow molding machine.

  The preform 11 in FIG. 5 shows a first example of a preform used for the stretch blow molding of the present invention. This preform 11 is formed on the bottom wall 15 of the bottom 14 as shown in FIG. In the predetermined center angle position portion 16a of the peripheral portion, which is the predetermined position portion 16, the uneven thickness portion 17 is formed by thickening inward.

Here, in the cooling process in the injection mold, the cooling rate of the thickened uneven portion 17 becomes slow, and as shown schematically by the cross hatch in FIG. The high temperature spot 18 can be formed in the central portion in the thickness direction.
In the hot parison method, the preform 11 that has been injection-molded as described above is taken out in a high temperature state that is not sufficiently cooled, and stretch blow molding is performed using the retained heat. However, this high temperature spot 18 can be sufficiently left.

  When the preform 11 in which the high temperature spot 18 is formed in the vicinity of the predetermined center angle position portion 16a of the peripheral portion of the bottom wall 15 is stretch blow molded in this way, the partial stretchability of the high temperature spot 18, that is, other portions On the other hand, utilizing the property of being partially stretched at a high magnification, the portion where the high-temperature spot 18 is partially stretched is formed into the integrated spot 7 of the container 1 of the first embodiment, which is shown in FIGS. As shown, a container 1 having an unconventional type of bottom wall 5 shape can be formed.

  Here, in the example of the schematic explanatory diagram of FIG. 9, the temperature adjustment pot 31 is divided into three blocks 33 with a heat insulating material interposed therebetween, so that the temperature control can be performed. Then, it can be divided and divided into several blocks 33 in this way. In the apparatus of FIG. 9, a temperature adjustment core 32 is disposed so as to be able to descend from above, and the temperature can be adjusted also from the inside of the preform 11.

  Next, FIGS. 6 and 7 show a second example and a third example of the preform used for the stretch blow molding of the present invention, respectively, and the bottom wall is the same as the preform 11 of the first example of FIG. 15 is formed in the vicinity of a predetermined center angle position 16a of the peripheral edge portion 15 of the bottle, and an accumulation spot 7 is formed in a predetermined central angle position portion of the peripheral edge portion of the bottom wall 5 as shown in FIG. This is prepared for molding a stretch blow molded container.

The preform 11 shown in FIG. 6 is a thin-walled uneven portion 17 having a relatively thin wall thickness at a predetermined center angle position 16 a of the peripheral edge of the bottom wall 15.
In the preform 11 having such a thin uneven portion 17 formed, the preform 11 is heated by an infrared heater or the like by a cold parison method and adjusted to a temperature suitable for stretch blow molding. The high-temperature spot 18 can be formed by utilizing the fact that the heating rate at the thin-walled uneven thickness portion 17 is large as compared with FIG.

Since the temperature of the preform can be adjusted by heating according to the hot parison method, the hot parison method is applied to the preform 11 having the thin wall uneven portion 17 as shown in FIG. It is also possible to form.

The preform 11 of FIG. 7 forms a vertical band-shaped vertical uneven portion 19 having a wall thickness in the vertical direction extending from the body portion 13 to the bottom portion 14 of the preform 11 at a predetermined center angle position, A thick wall thickness portion 17 is formed at a predetermined center angle position portion of the peripheral edge portion of the bottom wall 15 by the vertical wall thickness portion 19.
Like the preform 11 of FIG. 5, this preform 11 is formed with a thick-walled uneven portion 17 at a predetermined center angle position portion of the peripheral portion of the bottom wall 15, and a cooling rate in the injection mold. The high temperature spot 18 can be formed using the difference.

  The preform 11 shown in FIG. 7 has a vertical band-shaped vertical wall thickness portion 19 having a thick wall thickness in the vertical direction, and a thick wall thickness portion 17 is formed on the peripheral edge of the bottom wall 15. In contrast, the preform 11 is formed with a longitudinal strip-shaped longitudinally-thickened portion in which the wall thickness is thinned in the longitudinal direction in the preform 11, and a thin-walled unevenly-thickened portion is formed at the peripheral portion of the bottom wall 15. In this case, similarly to the parison 11 of FIG. 6, the high temperature spot 18 can be formed in the temperature adjustment process by heating by the cold parison method or the hot parison method.

Next, FIG. 4 illustrates a second embodiment of the stretch blow molded container of the present invention. This embodiment is an example in which the predetermined position portion 6 is a central portion 6c of the bottom wall 5, and the thickness of the bottom wall 5 is reduced in a convergent shape from the peripheral edge of the bottom wall 5 toward the central portion 6c. The inner surface of the bottom wall 5 is inclined downward in a convergent shape so that the content liquid Lq remaining in the vicinity of the inner surface of the bottom wall 5 is accumulated in the accumulation spot 7 formed in the central portion 6c.
Here, as shown in FIG. 4, if the tip of the suction pipe 23 is disposed so as to substantially touch the lowest part of the inner surface of the bottom wall 5, this tip position can be stably held. Can do.

  A preform 11 in FIG. 8 shows a fourth example of a preform used in the stretch blow molding of the present invention, and this preform 11 is a predetermined position portion 16 of the bottom wall 15 as shown in FIG. The central portion 16c is thickened in both the inner and outer directions to form the uneven thickness portion 17, and the high temperature spot 18 is formed by utilizing the difference in the cooling rate in the injection mold. be able to.

  Then, the preform 11 in which the high temperature spot 18 is formed in the central portion 16c of the bottom wall 15 as described above is stretch blow molded so that the portion where the high temperature spot 18 is partially stretched is the second embodiment (see FIG. 4). 4), and the container 1 having the shape of the bottom wall 5 which is unconventional and thins in a converging shape from the peripheral part toward the central part 6c as shown in FIG. can do.

  The preform 11 in FIG. 8 is formed by forming a thick-walled uneven portion 17 at the center portion 16c of the bottom wall 15. Conversely, a preform having a thin-walled uneven portion 17 formed at the center portion 16c. 11 can be prepared. In this case, the high temperature spot 18 can be formed in the central portion 16c in the temperature adjustment process by heating by the cold parison method or the hot parison method.

As mentioned above, although embodiment of this invention was described along the Example, the aspect of this invention is not limited to these Examples.
A feature of the stretch blow molding method of the present invention is that a thin or thick uneven part is intentionally formed on the bottom wall of the preform, and the cooling process and temperature in the injection mold are made using this uneven part. A high temperature spot is formed in the adjustment process, and the uneven stretchability of this high temperature spot is used. Within such a basic technical range, the shape of the uneven thickness part and the cooling process in the injection mold The temperature adjustment step by the hot parison method and the cold parison method can be performed in various combinations.
Moreover, although the container of the said Example had a cylindrical trunk | drum, it can also be set as an ellipse, an ellipse, a rectangle, and a polygonal cylindrical bottle type container.

  As described above, the bottle-type container by stretch blow molding of the present invention realizes an accumulation spot that has an unprecedented bottom wall shape. The content liquid can be used up to the end without being particularly conscious of the direction and the like, and it is expected to be widely used in the field of dispensing containers for cosmetics and the like.

It is a partial vertical side view of 1st Example of the stretch blow molding container of this invention. It is a bottom view of the container of FIG. It is a perspective view of the bottom part vicinity of the container of FIG. It is a partial vertical side view of 2nd Example of the stretch blow molding container of this invention. (A) which shows the 1st example of the preform used for the stretch blow molding of this invention is a partial vertical side view, (b) is a bottom view. (A) which shows the 2nd example of the preform used for the stretch blow molding of this invention is a partial vertical side view, (b) is a bottom view. (A) which shows the 3rd example of the preform used for the stretch blow molding of this invention is a partial vertical side view, (b) is a bottom view. (A) which shows the 4th example of the preform used for the stretch blow molding of this invention is a partial vertical side view, (b) is a bottom view. It is a schematic explanatory drawing of the temperature control pot used for a hot parison method. It is a partial vertical side view which shows the prior art example of an extending | stretching blow molding container, and shows the state which attached the extraction pump to the nozzle part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; Container 2; Mouth part 3; Body 4; Bottom 5; Bottom wall 6; Predetermined position part 6a; Predetermined center angle position part 6c; Central part 7; Accumulated spot 11; Preform 12; Portion 14; bottom 15; bottom wall 16; predetermined position portion 16a; predetermined center angle position portion 16c; central portion 17; wall thickness portion 18; high temperature spot 19; vertical wall thickness portion 21; ; Suction pipe 31; Temperature control pot 32; Temperature control core 33; Block 101; Container 103; Body part 104; Bottom part 105; Bottom wall Lq; Liquid

Claims (10)

In a stretch blow molding method for a synthetic resin bottle-shaped container, the wall thickness is added to a predetermined position portion (16) of the bottom wall (15) of the bottom portion (14), and the predetermined position portion of the bottom wall (15) ( A test tubular preform (11) formed with an uneven thickness portion (17) that is thick or thin compared to the thickness of the portion excluding (16) is injection-molded, and the uneven thickness portion (17 ) In the injection molding process or the temperature adjustment process in which the preform (11) is adjusted to a temperature suitable for the stretch blow process, by utilizing the difference in cooling or heating rate, the uneven thickness portion (17 ) In the bottom wall (15) is formed a high temperature spot (18) that is partially higher than the temperature of the portion excluding the uneven thickness portion (17), then, in the stretch blow step, The high temperature spot (18) is stretched and deformed to a relatively thin wall by utilizing the partial stretchability of the high temperature spot (18) of the bottom wall (15), and the high temperature spot (18) is stretched and deformed. The thickness of the bottom wall (5) of the bottle-shaped container (1) is reduced toward the predetermined position portion (6) in a convergent shape, thereby the bottom wall (5) toward the predetermined position portion (6). The inner surface of the bottom of the bottom wall (5) in the vicinity of the predetermined position portion (6) is formed and the content liquid (Lq) remaining in the vicinity of the inner surface of the bottom wall (5) is collected and collected in a convergent shape. 7) forming method. The molding method is based on the hot parison method, the uneven thickness portion (17) of the bottom wall (15) of the preform (11) is injection-molded to be relatively thick, and the uneven thickness portion (17) depends on the uneven thickness state. The molding method according to claim 1, wherein the hot spot (18) is formed in the uneven thickness portion (17) by utilizing a difference in cooling rate in the injection mold. The molding method is the cold parison method, the uneven thickness part (17) of the bottom wall (15) of the preform (11) is injection molded to a relatively thin wall, and the preform once taken out by the injection mold is once at room temperature. The temperature adjustment process shall be adjusted to a temperature suitable for the stretch blow process by heating the preform (11) with a heating device, and the heating rate due to the wall thickness during the temperature adjustment by the heating The molding method according to claim 1, wherein a high-temperature spot (18) is formed in the uneven thickness portion (17) using the difference between the two. A predetermined position portion (16) of the bottom wall (15) of the preform (11) is defined as a predetermined center angle position portion (16a) of the peripheral edge of the bottom wall (15), and the bottom wall (5) of the container (1) The molding method according to claim 1, 2 or 3, wherein the predetermined position portion (6) is a predetermined center angle position portion (6a) of the peripheral edge of the bottom wall (5). A vertical band-shaped vertical wall thickness portion (19) in which the wall thickness is thick or thin in the vertical direction from the body portion to the bottom portion of the preform (11) at a predetermined center angle position is formed. The molding method according to claim 4, wherein the uneven thickness portion (17) is formed at the predetermined central angular position portion (16a) of the peripheral edge portion of the bottom wall (15) by the portion (19). A predetermined position portion (16) of the bottom wall (15) of the preform (11) is a central portion (16c) of the bottom wall (15), and a predetermined position portion (6) of the bottom wall (5) of the container (1) (6). The molding method according to claim 1, 2 or 3, wherein the center portion (6c) of the bottom wall (5) is the center portion (6c). A bottle-shaped container made of synthetic resin by a stretch blow molding method, wherein the thickness of the bottom wall (5) of the bottom (4) is converged toward a predetermined position portion (6) of the bottom wall (5). By reducing the thickness, the inner surface of the bottom wall (5) is inclined in a convergent manner toward the predetermined position portion (6), and the bottom wall (5) is formed in the vicinity of the predetermined position portion (6). A stretch blow molded container characterized in that an accumulation spot (7) is formed in which the content liquid (Lq) remaining in the vicinity of the inner surface of the glass fluidly collects in a convergent shape. The stretch blow molded container according to claim 7, wherein the predetermined position portion (6) is a predetermined center angle position (6a) portion of the peripheral portion of the bottom wall (5). The stretch blow molded container according to claim 7, wherein the predetermined position portion (6) is a central portion (6c) of the bottom wall (5). A pumping pump (21) having a suction pipe (23) extended to suck up the liquid content downward is assembled to the mouth tube (2) and used as a pumping container. The stretch blow molded container according to 7, 8 or 9.

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