JPH0662157B2 - Bottle body made of saturated polyester resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a saturated polyester resin biaxially stretch blow molded bottle.

[Prior Art] Saturated polyester resin biaxially stretched blow molded bottles have many advantages such as excellent gas barrier properties, glass-like transparency, toughness that does not break even when dropped, and hygiene.

However, when this saturated polyester resin biaxially stretched blow molded bottle body is molded into a normal glass bottle shape, the bottle bottom portion is molded without being stretched. And since the bottom part is not stretched, the mechanical strength is inferior, it is likely to be deformed by the load of internal pressure, and when it is filled with high temperature contents, it causes deformation due to heat shrinkage, and also causes a capacity change. A bottle having the above problem is formed.

Various inventions relating to the bottom structure have been made to solve this drawback.

As one of them, as shown in FIGS. 9 to 12, there is a central recessed portion (20) surrounded by a protruding annular heel portion (22) at the bottom, and the radial direction of the heel portion (22). The inner edge is moved to the recessed part (20),
A plurality of ribs (24) protruding outward so as to interrupt the outer surface of (20) are arranged symmetrically around the central axis of the bottle and the longitudinal direction of each rib (24) is oriented in the radial direction. Has been invented by a distributed bottom structure (Japanese Patent Publication No. 57-57330).
No.).

In this bottom structure, adjacent ribs are separated from each other by a part of the wall of the recess. Also, the lateral edge between the rib and the outer surface of the recessed portion is shaped to smoothly transition to the adjacent portion of the bottom structure.

[Problems to be solved by the invention]

However, in the above-mentioned known invention, the recessed portion is left unstretched and the heat resistance is not sufficient. Therefore, for example, when the contents such as juice are heated and filled by a counter pressure type filling machine, after filling, the contents are cooled to room temperature, the volume contraction of the contents causes a pressure reduction, and the shape of the bottom of the bottle may be deformed. is there.

Therefore, a problem to be solved by the present invention is to provide a bottle body made of a saturated polyester resin which has resistance to internal pressure deformation, heat deformation resistance and reduced pressure absorption.

[Means for solving problems]

The saturated polyester resin bottle of the present invention is a saturated polyester resin biaxially stretched blow molding bottle, which has an annular bottom heel portion (1) in contact with the floor surface, and the bottle is radially inward of the bottom heel portion. It has an annular flat panel portion that is raised toward the inside of the body and that is substantially parallel to the floor surface, and further has a recessed portion toward the inside of the bottle on the inside in the radial direction, and the main part of the surface of the recessed portion is A plurality of quadrangular pyramids are connected concentrically in the circumferential direction in a plurality of rows, and are formed in a concavo-convex surface shape that undulates along the upper surface of the quadrangular pyramid aggregate.

Thus, in the present invention, "biaxially stretched blow molded bottle made of saturated polyester resin"
Is a hollow molding bottle obtained by forming a bottomed parison by injection molding using polyethylene terephthalate, and then blow molding the obtained bottomed parison, or while maintaining the shape after molding the hollow molding bottle. It means a hollow molding bottle obtained by heat-treating polyethylene terephthalate at a temperature not lower than the glass transition point and not higher than the melting point temperature. Further, the “saturated polyester resin biaxially molded bottle” of the present invention is not limited to a single-layer hollow molded bottle, but may be a multilayer hollow molded bottle.

Examples of the multi-layer hollow molding bottle to which the present invention can be applied include polyarylate, polycarbonate, polybutylene terephthalate, polyester-polycarbonate copolymer, polyacetal, nylon, etc., and polyethylene terephthalate / polyarylate / polyethylene terephthalate by injection molding. Polyethylene terephthalate / polycarbonate / polyethylene terephthalate, polyethylene terephthalate / polybutylene terephthalate / polyethylene terephthalate, polyethylene terephthalate / polyester / polycarbonate copolymer / polyethylene terephthalate, polyethylene terephthalate / polyacetal / polyethylene terephthalate, polyethylene terephthalate / nylon /
A hollow molding bottle formed by forming a three-layered bottomed parison such as polyethylene terephthalate and then blow molding the bottomed parison, or a glass of polyethylene terephthalate while maintaining the shape after molding the hollow molding bottle. An example is a hollow molding bottle which is heat-treated at a temperature not lower than the transition point and not higher than the melting point temperature.

Next, in the present specification, the term "quadrangular pyramid" means not only a square pyramid having a perfect base, but also a rhombus, a trapezoid,
Or, it means that it also includes irregularly shaped quadrangular pyramids such as parallelograms.

In the present invention, the main part of the surface of the recessed portion is formed into an uneven surface shape that undulates along the upper surface of the quadrangular pyramid aggregate, but the uneven surface shape of a plurality of triangular pyramids that continuously form the recessed area other than the main part It may be formed in.

[Work]

In the present invention, the surface of the recessed portion is formed into an uneven surface shape which is undulated along the upper surface of the quadrangular pyramid aggregate, whereby the recessed portion is stretched at a relatively high degree of stretching.

Further, the ridges which are undulated and connected so as to form a triangular mesh function as a beam.

When the internal pressure of the bottle is vertically applied to the recessed portion, the sloped region of the recessed portion corresponding to the surface of each quadrangular pyramid is pressed vertically. As a result, in the ridge region of the recessed portion corresponding to each ridge or connection portion of the quadrangular pyramid assembly, the directions opposite to each other from the recessed portion inclined surface regions corresponding to both quadrangular pyramids adjacent through the twill or the connection portion are provided. The horizontal force of is loaded. That is, the recessed portion surface regions corresponding to the respective quadrangular pyramids are in a state of mutually supporting each other, and a function of resisting a high internal pressure can be exerted.

Next, in the present invention, the flat panel portion is provided to the heel portion via the slant wall portion, and when the internal pressure of the bottle body is reduced, a deformation similar to a hinge is caused, and the bottle body is formed. It has the function of relaxing the applied pressure.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 and 2 show a first embodiment of a bottle of saturated polyester resin according to the present invention.

FIG. 1 is a plan view of the bottom of a bottle according to the first embodiment of the present invention, FIG. 2 shows the end face cut along the line OA shown in FIG. 1 on the left side, and the line OB shown in FIG. 1 on the right side. It is a figure which shows the cut | disconnected end surface.

The bottle body of the present invention has an annular bottom heel portion (1) which is grounded on the floor surface.
A flat panel portion (2) that is substantially flat with an annular floor surface that is raised toward the inside of the bottle through a slant wall portion is provided on the inner side in the radial direction of the bottom heel portion. Furthermore, the recessed part (3) facing the inside of the bottle is located radially inward of the flat panel part (2).
Is provided. Incidentally, (4) shows a central portion of a plane connected to the recessed portion (3), and (5) shows a spherical convex portion directed to the outside provided at the center of the bottom portion.

The surface of the recessed portion (3) has a plurality of triangular planes undulating along the upper surface of a quadrangular pyramid aggregate in which a plurality of quadrangular pyramids each having a rhombus shape or a rhombus-like shape continuous in a concentric manner in the circumferential direction It is formed in a continuous uneven surface shape.

That is, the quadrangular pyramid surface (upper surface of the quadrangular pyramid) A ₁ , A ₂ , A ₃ , ... is arranged in a ring shape so as to be connected to each other at the corner, and further, the quadrangular pyramid surface A ₁ B ₁ is located between A ₂ , B ₂ is located between A ₂ and A ₃ , and so on, and so on.
B ₁ , B ₂ ... Are arranged in a ring so that Bn (n ≧ 3) is located between An and An + 1.

Due to this concave-convex curved surface structure of the recessed portion (3), the bottom surface area is greatly expanded compared to a simple recessed curved surface.In the biaxial stretch blow molding process, this structure of the bottom recessed portion (3) is ,
This has the effect of promoting the stretching of this portion and giving the stretching effect.
In addition, since the vertices a _{1 to} a ₈ and b _{1 to} b _{8 of the} quadrangular pyramid protrude inside the bottle, the internal pressure deformation resistance and the heat deformation resistance are significantly improved.

The flat panel surface (2) has a function of relieving the pressure applied to the bottle by causing a deformation similar to a hinge when the inside of the bottle is decompressed. This function works effectively when filling bottles at high temperature with a counter pressure type filling machine.

That is, when a counter pressure of +0.2 to 0.8 kg / cm ² is applied, the flat panel part is displaced downward and installed on the bottom surface to increase the internal volume of a certain amount, and after filling, the counter pressure is increased. When removed, the original volume can be blocked to reduce the internal volume and consequently the headspace. Further, after the kip sealing and cooling, the flat panel portion is displaced upward with respect to the pressure reduction due to the volume reduction of the content fluid, and as a result, the internal volume moderates the pressure reduction.

3 and 4 show a second embodiment.

FIG. 3 is a plan view of the bottom of the bottle according to the second embodiment of the present invention, FIG. 4 shows the end face cut along the line OA shown in FIG. 3 on the left side, and the line OB shown in FIG. 3 on the right side. It is a figure which shows the cross section which shows the cut | disconnected end surface.

This embodiment is different from the first embodiment in that each quadrangular pyramid surface is smaller than that in the first embodiment, and four circular pyramidal surface annular arrays are concentrically formed in four rows. Also, the recessed part
(3) is formed by a concavo-convex bent surface formed by connecting only triangular planes. Further, quadrangular pyramid vertex _{a 1 ~a 8, b 1 ~b} 8, c 1 ~
All of c ₈ and d _{1 to} d ₈ are located so as to project toward the inside of the bottle.

Further, FIGS. 5 and 6 show a third embodiment.

FIG. 5 is a plan view of the bottom of a bottle according to a third embodiment of the present invention, FIG. 6 shows the end face cut along the line OA shown in FIG. 5 on the left side, and the line OB shown in FIG. 5 on the right side. It is a figure which shows the cut | disconnected end surface.

This embodiment is different from the first and second embodiments in that the surface of the concave portion (3) has a concave-convex shape along the upper surface of a quadrangular pyramid continuous body in which quadrangular pyramids having a trapezoidal bottom surface are connected. Has been formed. An annular array of quadrangular pyramid surfaces A _{1 to} A ₈ having a trapezoidal bottom surface and an annular array of quadrangular pyramid surfaces B _{1 to} B ₈ are formed by connecting concavo-convex bent planes.

Further, FIGS. 7 and 8 show a fourth embodiment.

FIG. 7 is a plan view of the bottom of the bottle according to the fourth embodiment of the present invention, FIG. 8 shows the end face cut along the line OA shown in FIG. 7 on the left side, and the line OB shown in FIG. 7 on the right side. It is a figure which shows the cut | disconnected end surface.

In this embodiment, the concave surface (3) is a circular array of quadrangular pyramidal surfaces A _{1 to} A _8, a circular array of quadrangular pyramidal surfaces B _{1 to} B ₈ , and a circular array of irregular triangular pyramidal surfaces C _{1 to} C ₈ . Consists of concavo-convex curved surfaces formed by connecting triangular flat surfaces, which are concentrically formed.

〔The invention's effect〕

The bottle of the present invention described above is the Japanese Patent Publication No. 57-5733.
0, etc., unlike the bottle body having a plurality of ribs extending from the inside of the bottom recessed portion toward the heel, the recessed portion continuously connects the quadrangular pyramids in the circumferential direction. Since the sharp triangular bent surface is formed, the internal pressure deformation resistance and the heat deformation resistance can be remarkably improved. Furthermore, since the quadrangular pyramid vertices are located inside the bottle and project inward, the quadrangular pyramid vertices are sharply formed in the stretching process, and many sharp quadrangular pyramid surfaces alternate. By virtue of this, the heat-deformation resistance of the bottom recess is significantly improved.

Further, by providing the flat panel portion, it has a function of reducing pressure and pressure suitable for hot fill.

[Brief description of drawings]

1 to 8 show an embodiment of the present invention, and FIG. 1 is a plan view of a bottom portion of a bottle body according to the first embodiment of the present invention.
The left side shows the end face cut along the line OA shown in the first figure, the right side shows the end face cut along the line OB shown in the first figure, and FIG. 3 shows the bottle according to the second embodiment of the present invention. 4 is a plan view of the bottom, and FIG. 4 shows the end face cut on the OA line on the left side in FIG.
The right side is a view showing the end face cut along the OB line shown in the third drawing, the fifth drawing
The figure is a plan view of the bottom of a bottle according to a third embodiment of the present invention,
FIG. 6 shows the end surface cut along the OA line shown in FIG. 5 on the left side, and the end surface cut along the OB line shown in FIG. 5 on the right side.
FIG. 7 is a plan view of the bottom of a bottle according to a fourth embodiment of the present invention, FIG. 8 shows an end face obtained by cutting the left side with OA line shown in FIG. 7, and the right side with OB line shown in FIG. The figure which shows the cut | disconnected end surface, FIG. 9 is a side view which shows the bottle-shaped container described in Japanese Patent Publication No.57-57330, FIG. 10 is the enlarged plan view of the bottom part of the bottle of FIG. 9, and FIG. Is an enlarged crushing sectional view taken along line 3-3 of FIG. 9, and FIG. 12 is an enlarged crushing sectional view of the bottle shown in FIG. 1 taken along line 4-4 of FIG.

Claims (1)

[Claims] 1. A biaxially stretched blow-molded bottle body made of saturated polyester resin, which has an annular bottom heel portion in contact with the floor surface, and an annular ring which is raised radially inward of the bottom heel portion toward the inside of the bottle body. Has a flat panel portion substantially parallel to the floor surface, and further has a recessed portion facing inward of the bottle inside the radial direction, and the main portion of the surface of the recessed portion is a plurality of quadrangular pyramids concentric in the circumferential direction. A bottle body made of a saturated polyester resin, characterized in that the bottle body is formed in a concavo-convex shape that is undulated along the upper surface of a quadrangular pyramid aggregate that is continuous in a row.