BLOW MOLDED BOTTLE WITH UNFRAMED FLEX PANELS

BOUTEILLE MOULEE PAR EXTRUSION-SOUFFLAGE COMPORTANT DES PAROIS FLEXIBLES A BORDURES NON RENFORCEES

English Abstract

A hot-fillable, slender, blow-molded plastic bottle (10, 110, 210)
for use in containing hot-filled beverages. The bottle (10, 110, 210) has
a sidewall (16, 116, 216) with various interactive zones of function. For
example, some of the zones are primarily responsible for accommodating
vacuum absorption, while other zones are primarily intended to rigidify
the container (10, 110, 210) such as by providing post strength to improve
container top loading capability. Although each zone may have a primary
function, each zone also aids adjacent zones in providing their functions.
Thus, the entire sidewall (16, 116, 216), and not merely selected locations,
reacts to the forces generated by the hot-fill process on the container (10,
110, 210).

French Abstract

La présente invention concerne une bouteille (10, 110, 210) en plastique moulée par extrusion-soufflage, non bombée, remplissable à chaud utilisée pur contenir des boissons remplies à chaud. Cette bouteille (10, 110, 210) présente une paroi latérale (16, 116, 216) comportant des zones de fonction interactives variées. Par exemple, quelques zones ont pour fonction essentiellement d'amortir les différences de dépression, alors que d'autres sont essentiellement prévues pour rigidifier le récipient (10, 110, 210), en lui conférant par exemple un effet de pilier lui permettant de résister à l'effondrement vertical. Bien que chaque zone puisse présenter une fonction primaire, chaque zone aide les zones adjacentes à remplir leurs fonctions. Ainsi, la totalité de la paroi (16, 116, 216), et pas seulement des endroits sélectionnés, réagissent aux forces produites par le processus de remplissage à chaud du récipient (10, 110, 210).

Claims

Claims:
1. A blow-molded plastic bottle (10, 110, 210) having a dome (12, 112, 212)
with an upstanding finish (18, 118, 218), a base (14, 114, 214), and a
substantially
tubular sidewall (16, 116, 216) between the base (14, 114, 214) and the dome
(12,112, 212), said sidewall (16, 116, 216) comprising:
an alternating pattern of a plurality of circumferentially-spaced vertically-
elongate columns (24, 124, 224) and a plurality of circumferentially-
spaced substantially smooth-surfaced panels (22, 122, 222);
each of said columns (24, 124, 224), as formed, being outwardly convex in
horizontal cross section and each of said panels (22, 122, 222), as
formed, being inwardly concave in horizontal cross section with each
of said panels (22, 122, 222) extending laterally between and
connecting directly to an adjacent pair of said columns (24, 124, 224);
and
each of said columns (24, 124, 224), as formed, being outwardly convex in
vertical cross section and each of said panels (22, 122, 222), as
formed, being inwardly concave in vertical cross section with each of
said columns (24, 124, 224) and panels (22, 122, 222) having opposite
ends merging directly into adjacent portions of the bottle (10, 110,
210).
2. A blow-molded plastic bottle (10, 110, 210) according to claim 1, wherein
each of said panels (22, 122, 222) flexes outwardly during hot-filling and
inwardly in
response to a reduction in internal volume when the bottle (10, 110, 210) is
capped
and permitted to cool; and wherein said inward deflection of said panels (22,
122,
222) increases the horizontal cross-sectional convexity of each of said
columns (24,
124, 224), whereby said increased horizontal cross-sectional convexity
structurally
enhances bottle strength.


3. A blow-molded plastic bottle (10, 110, 210) according to claim 2, wherein
each of said as-formed outwardly convex vertical cross-sections of each column
(24,
124, 224) straightens in response to the reduction in internal volume when the
bottle
(10, 110, 210) is hot-filled, capped and permitted to cool; and wherein said
vertical
straightening structurally enhances the strength of the bottle (10, 110, 210).

4. A blow-molded plastic bottle (10, 110) according to claim 3, further
comprising a plurality of vertically-aligned finger alignment protrusions
(32,132)
formed integrally on each of said columns (24, 124).

5. A blow-molded plastic bottle (10, 110) according to claim 4, wherein said
sidewall (16, 116) has a number of said panels (22, 122) in a range of two
through
ten and an equal number of said columns (24, 124).

6. A blow-molded plastic bottle (10, 110) according to claim 5, wherein said
sidewall (16, 116) has five of said panels (22, 122) and five of said columns
(24, 124)
affording side-by-side packing with like bottles (10, 110) in a minimum of
space with
said columns (24, 124) of one bottle (10, 110) interdigitating with said
panels (22,
122) of adjacent bottles (10, 110).

7. A slender blow-molded plastic bottle (10, 110, 210) comprising:
an upper portion with a dome (112, 112, 212) having an upstanding
finish (18, 118, 218) capable of being sealed with a closure;
a lower portion having a base (14, 114, 214); and
a generally tubular intermediate sidewall portion (16, 116, 216)
between said upper and lower portions, said sidewall portion
(16, 116, 216) being formed with a plurality of
circumferentially-spaced vertically-elongate columns (24, 124,
224) in an alternating pattern with a plurality of

11





circumferentially-spaced substantially smooth-surfaced panels (22, 122,
222);
each of said columns (24, 124, 224), as formed, being outwardly convex in
horizontal cross section and each of said panels (22, 122, 222), as
formed, being inwardly concave in horizontal cross section such that
each of said panels (22, 122, 222) extends laterally between and
connects directly to an adjacent pair of said columns (24, 124, 224);
each of said columns (24, 124, 224), as formed, being outwardly convex in
vertical cross section and each of said panels (22, 122, 222), as
formed, being inwardly concave in vertical cross section such that each
of said columns (24, 124, 224) and panels (22, 122, 222) has opposite
ends which merge directly into adjacent portions of the bottle (10, 110,
210);
each of said panels (22, 122, 222) flexing outwardly to expand the
volume of the bottle (10, 110, 210) during hot-filling and each
of said panels (22, 122, 222) flexing inwardly in response to a
reduction in internal volume after the bottle (10, 110, 210) is
capped and permitted to cool; and
said inward deflection of said panels (22, 122, 222) functioning to
increase the horizontal cross-sectional convexity of each of said
columns (24, 124, 224) and of decreasing the vertical cross-
section convexity of each of said columns (24, 124, 224).
8. A slender blow-molded plastic bottle (10, 110) according to claim 7,
further comprising a plurality of vertically-aligned finger alignment
protrusions (32,
132) formed integrally on each of said columns (24, 124) to define
therebetween
finger grip locations and to structurally reinforce said columns (24, 124) at
desired
locations.
12



9. A slender blow-molded plastic bottle (10, 110) according to claim 7,
wherein each of said panels (22, 122) has a vertical center line and a pair of
lateral
side edges, and each of said columns (24, 124) has a vertical center line and
a pair of
lateral side edges; wherein, in the as-formed condition of the bottle (10,
110), each of
said panels (22, 122) at said panel center line extends radially inward a pre-
determined
distance relative to said panel side edges and each of said columns (24, 124)
at said
column center line extends radially outward a pre-determined distance relative
to said
column side edges; wherein said column and panel side edges lie on a
cylindrical
datum plane (D); and wherein said pre-determined distances of said panels and
columns are substantially equal.
10. A slender blow molded plastic bottle (10, 110) according to claim 9,
wherein said pre-determined distances of said panels (22, 122) and said
columns (24,
124) are in the range of about 1 to about 4 mm.
11. A slender blow-molded plastic bottle (10) according to claim 7, wherein
each of said columns (24) has a substantially rectangular periphery.
12. A slender blow molded plastic bottle (110) according to claim 7, wherein
each of said columns (124) has an hourglass-shaped configuration with a
minimum
peripheral extent at about a vertical median of the sidewall (116).
13. A slender blow-molded plastic bottle (10, 110) according to claim 7,
wherein each of said panels (22, 122) and each of said columns (24, 124) has
upper
peripheral edges positioned in an end-to-end array having a substantially
circular
horizontal cross-sectional shape; and wherein each of said panels (22, 122)
and each
of said columns (24, 124) have lower peripheral edges positioned in an end-to-
end
array having a substantially circular horizontal cross-sectional shape.
13



14. A slender blow-molded plastic bottle (10, 110) according to claim 13,
wherein said sidewall portion (16, 116) has two to ten of said panels (22,
122) and an
equal number of said columns (24, 124).
15. A blow-molded slender plastic bottle (10, 110) comprising:
a dome (12, 112) having an upper portion with an upstanding sealable
finish (18, 118) and a lower portion with a circumferential
groove providing a waist (20);
a base (14, 114); and
a tubular sidewall (16, 116) between said dome (12, 112) and said base
(14, 114), said sidewall (16, 116) being formed with a plurality
of circumferentially-spaced vertically-elongate columns (24,
124) disposed in an alternating pattern with a plurality of
circumferentially-spaced substantially smooth-surfaced panels
(22, 122);
each of said columns (24, 124), as formed, being outwardly convex in
horizontal cross section and each of said panels (22, 122), as
formed, being inwardly concave in horizontal cross section
such that each of said panels (22, 122) extends laterally
between and merges directly with an adjacent pair of said
columns (24, 124);
each of said columns (24, 124), as formed, being outwardly convex in
vertical cross section and each of said panels (22, 122), as
formed, being inwardly concave in vertical cross section such
that each of said columns (24, 124) and panels (22, 122) has
opposite ends which merge directly into said dome (12, 112)
and base (14, 114) of the bottle (10, 110);
14



each of said panels (22, 122) flexing outwardly to expand the volume
of the bottle (10, 110) during hot-filling and each of said panels
(22, 122) flexing inwardly in response to a reduction in internal
volume when the bottle (10, 110) is capped and permitted to
cool; and
said inward deflection of said panels (22, 122) increasing the horizontal
cross-sectional convexity and decreasing the vertical cross-
sectional convexity of each of said columns (24, 124) for
structurally enhancing bottle top loading strength.
16. A blow-molded slender plastic bottle (10, 110) according to claim 15,
further comprising a plurality of vertically-aligned outwardly protruding
finger
alignment protrusions (32, 132) formed integrally on each of said columns (24,
124)
to define finger grip locations and to structurally modify the strength of
said columns
(24, 124) at desired locations.
17. A blow-molded slender plastic bottle (10, 110) according to claim 15,
wherein each of said panels (22, 122) has a central portion with a periphery,
and each
of said columns (24, 124) has a central portion with a periphery; wherein, in
the as-
formed condition of the bottle (10, 110), each of said panels (22, 122) at
said central
portion extends radially inward a pre-determined distance relative to said
panel
periphery and each of said columns (24, 124) at said column central portion
extends
radially outward a pre-determined distance relative to said column periphery;
and
wherein said pre-determined distances of said panels (22, 122) and columns
(24, 124)
are substantially equal.
18. A blow-molded slender plastic bottle (10, 110) according to claim 15,
having a slenderness ratio of about 3.3:1.




19. A blow-molded slender plastic bottle (10, 110) according to claim 15,
having upper and lower bumpers (16a, 16b, 116a, 116b) above and below said
sidewall (16, 116), and wherein said columns (24, 124), in said bottle as-
formed
condition, lie within a cylindrical plane (P) tangent to said bumpers (16a,
16b, 116a,
116b).
20. A blow-molded slender plastic bottle (10, 110) according to claim 19,
having a cylindrical datum plane (D) coaxial with said first-mentioned
cylindrical plane
(P) and located inwardly thereof, said cylindrical datum plane (D) at said
sidewall
vertical median defining a reference with respect to which said columns (24,
124) and
said panels (22, 122) flex.
16

Description

CA 02370320 2001-11-06
WO 00/68095 PCT/US00/12625
BLOW MOLDED BOTTLE WITH UNFRAMED FLEX PANELS
Field of the Invention
The present invention relates to a slender bottle which integrates aesthetic
and
functional features without clearly segregating such features from one
another. More
particularly, the present invention relates to a slender blow-molded plastic
bottle
which is useful in packaging a hot-filled beverage.
Background of the Invention
In the packaging of beverages, especially juice, blow-molded plastic
containers
made from, for instance, PET, are used in the so-called "hot-fill" process in
which
containers are filled with a beverage at an elevated temperature. The hot-
filled
containers are promptly sealed and are permitted to cool resulting in internal
pressure
and temperature changes that reduce the volume of the sealed container.
It is known to provide hot-fillable containers with a series of well-defined,
spaced-apart vacuum flex panels to compensate for the internal volume
reduction.
The vacuum flex panels provide a suffcient amount of flexure without adversely
IS af~'ecting the structural integrity and aesthetic appearance of the hot-
filled container.
The adjacent portions of the container, such as the so-called lands, or
columns, which
are located between, above, and below the flex panels, are intended to resist
any
deformations which would otherwise be caused by hot-fill processing. Wall
thickness
variations, or geometric structures, such as ribs, projections and the like,
can be
utilized to prevent unwanted distortion. Generally, the typical hot-fillable
container
structure is provided with certain pre-defined areas which flex to accommodate
volumetric changes and certain other pre-defined areas which remain unchanged.
An example of a hot-fillable container having a plurality of flex-panels is
illustrated in U.S. Design Patent No. D.366,4I6 which is owned by the assignee
of the
present application. The hot-fill bottle has well-defined flex panels which
are
distinctly visually apparent prior to filling and which accommodate vacuum
induced
distortions after filling, capping and cooling. The container also has other
geometric
structures which are completely segregated from the flex panels, which are
distinctly



CA 02370320 2001-11-06
WO 00/68095 PCT/US00/12625
visually apparent prior to filling, and which resist structural change caused
by volume
reduction. Typically, all of these structures are framed about their entire
peripheries
and are completely separated from the bottle's aesthetic features which are
usually
limited to the dome of the container. For example, flex panels are often
indented from
adjacent vertically disposed lands and from circumferential upper and lower
label
mount regions. Conventionally, the indented panels merge into the adjacent
lands via
various stepped-shaped walls, grooves, projections or like structures.
Other examples of container sidewalls having flexible panels are disclosed in
U.S. Patent No. 4,749,092 issued to Sugiura et al.; U.S. Patent No. 3,923,178
issued
to Welker III; U.S. Patent No. 4,497,855 issued to Agrawal et al.; U.S. Patent
No.
5,740,934 issued to Brady; and U.S. Patent No. 5,704,504 issued to Bueno. The
Sugiura, Welker and Agrawal patents disclose inwardly deflecting vacuum flex
panels
which are located between substantially planar lands; the Bueno patent
discloses
inwardly deflecting panels which are located between spiral-shaped grooves;
and the
Brady patent discloses outwardly deflecting panels which intersect at
vertically
disposed corners.
Although various ones of the above referenced containers may function
satisfactorily for their intended purposes, there is a need for a hot-fillable
blow molded
bottle which integrates functional and aesthetic components in such a manner
as to
provide a package having enhanced visual interest. Such a package is
particularly
desirable in single-serve sizes wherein slenderness and single-handed
gripability are
desirable features.
Objects of the Invention
With the foregoing in mind, a primary object of the present invention is to
provide a hot-fillable bottle which integrates vacuum absorption, structural
reinforcement, and other functional features with aesthetic and ergonomic
properties
by providing various interactive functional zones in the container structure.
2



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Another object of the present invention is to provide a bottle having a
plurality
of alternating non-framed flex panels and non-framed lands, or columns, which
laterally merge together directly and which are jointly reactive to hot-fill
process
forces acting thereon.
A further object is to provide a blow-molded, plastic, slender bottle having a
grip structure which both enhances the structural integrity of the container
and the
visual appearance of the container.
Summary of the Invention
More specifically, the present invention provides a blow-molded plastic
container having a neck with an upstanding threaded finish, a close-ended
base, and a
tubular sidewall located between the base and the neck. The sidewall includes,
in an
alternating pattern, a plurality of circumferentially-spaced, vertically-
elongate columns
and a plurality of circumferentially-spaced substantially smooth-surfaced
panels. Each
of the columns, as formed, is outwardly convex in horizontal cross section,
and each
of the panels, as formed, is inwardly concave in horizontal cross section such
that each
of the panels extends laterally between and directly connects to an adjacent
pair of the
columns. In addition, each of the columns, as formed, is outwardly convex in
vertical
cross-section, and each of the panels, as formed, is inwardly concave in
vertical cross
section such that each of the columns and panels have opposite ends which
merge
directly into adjacent portions of the container.
Functionally, each of the panels flexes outwardly to expand the volume of the
container during hot-filling, and each of the panels flexes inwardly in
response to a
reduction in internal volume when the container is capped and permitted to
cool. The
inward deflection of the panels interactively increases the horizontal cross-
sectional
convexity of each column and decreases the vertical cross-sectional convexity
of each
column. The vertical straightening of each column and the lateral pinching of
each
column combine to structurally strengthen the container.
The aforedescribed structure is particularly suited for slender, single-serve
size
bottles.
3



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In a preferred embodiment, a plurality of vertically-aligned finger alignment
projections are formed integrally on each of the columns to define finger grip
locations, to structurally reinforce the columns, and to provide points of
visual
interest.
Brief Description of the Drawings
The foregoing and other objects, features and advantages of the present
invention should become apparent from the following description when taken in
conjunction with the accompanying drawings, in which:
FIG. I is an elevational view of a container embodying the present invention;
FIG. 2 is a vertical cross-sectional view taken along line 2--2 of the
container
illustrated in FIG. 1;
FIG. 3 is a horizontal cross-sectional view taken along line 3--3 of the
container illustrated in FIG. 1;
FIG. 4 is a horizontal cross-sectional view taken along line 4--4 of the
container illustrated in FIG. 1;
FIG. 5 is an elevational view of a second embodiment of a container according
to the present invention;
FIG. 6 is a vertical cross-sectional view taken along line 6--6 of the
container
illustrated in FIG. 5;
FIG. 7 is a horizontal cross-sectional view taken along line 7--7 of the
container illustrated in FIG. 5;
FIG. 8 is a horizontal cross-sectional view taken along line 8--8 of the
container illustrated in FIG. 5;
FIG. 9 is a horizontal cross-sectional view taken along line 9--9 of the
container illustrated in FIG. 5;
FIG. 10 is an elevational view of a third embodiment of a container according
to the present invention; and
FIG. 1 1 is an elevational view of the container illustrated in FIG. 10
rotated
30° about a vertical axis extending centrally through the container.
4



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Detailed Description of the Preferred Embodiments
One embodiment of a slender bottle, or container, 10 according to the present
invention is illustrated in FIG. 1. The container 10 has a dome 12, a close
ended base
14 and a sidewall 16 located between the dome and base. An upper portion of
the
dome 12 includes an upstanding threaded finish 18 to which a closure, such as
a cap,
(not shown) can be attached. A lower portion of the dome 12 includes a
circumferential groove, or waist, 20 which provides hoop strength to the
bottle to
resist ovalization distortion which may otherwise result due to hot-filling
and to stiffen
the transition between the lower portion of the dome and the sidewall.
Optionally, a
label can be mounted on the dome 12 between the finish 18 and the groove 20.
Certain novel aspects of the illustrated preferred embodiment are located in
the
sidewall 16 which is inset between an upper bumper 16a and a lower bumper 16b
and
lies entirely within an imaginary cylindrical plane "P" tangent to the outer
surface of
both. Functionally, the sidewall 16 is capable of expanding when the bottle is
filled
and is capable of accommodating vacuum absorption when the hot-filled bottle
is
capped and permitted to cool. In addition, the sidewall 16 is provided with
structure
which enhances grip-ability of the container 10 and the aesthetic visual
appearance of
the container 10.
The sidewall 16 is provided with various interactive zones of function. For
example, some of the zones are primarily responsible for accommodating vacuum
absorption, while other zones are primarily intended to rigidify the container
such as
by providing post strength to improve container top loading capability.
Although
each zone may have a primary function, each zone also aids adjacent zones in
providing their functions. Thus, the entire sidewall 16, and not merely
selected
locations, reacts to the forces generated by the hot-fill process on the
container 10.
To this end, a plurality of unframed and substantially smooth-surfaced flex
panels 22 are provided on the sidewall 16 in an alternating pattern with a
plurality of
vertically elongate columns 24. The panels 22 provide zones of expansion and
vacuum absorption, and the columns 24 provide structural reinforcement zones.
Both
the panels 22 and the columns 24 react to the forces created by hot-fill
processing.
5



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In the "as-formed" condition, ie. after blow-molding but before hot-filling,
and
in the absence of any internal or external applied forces, the panels 22 are
slightly
inwardly concave. This is best illustrated in the vertical cross-section of
the right hand
side of FIG. 2, and in the horizontal cross sections illustrated in FIGs. 3
and 4. The
deepest inset portion 26 of each panel 22 is located at the intersection of
its vertical
centerline 28 and its horizontal centerline 30. In the embodiment illustrated
in FIGs.
I-4, each panel 22 is substantially rectangular and is not surrounded by any
framing
structure such as a stepped wall portion. Rather, all the peripheral edges of
each
panel 22 merge directly into the adjacent portions of the container as will be
discussed.
In the as-formed condition, the columns 24 are slightly outwardly convex.
This is best illustrated in the vertical cross-section of the left hand side
of FIG. 2, and
in the horizontal cross sections illustrated in FIGS. 3 and 4. Each column 24
is
substantially rectangular and is not surrounded by any distinct framing
structure, such
as a stepped wall. Rather, each column 24 merges smoothly and directly into
the
adjacent portions of the container. For example, the lateral edges of each
panel 22
merge directly into the side edges of an adjacent pair of columns 24. The
juncture of
the panels 22 and columns 24 are not delineated by other structure; rather,
they
smoothly transition directly into one another. As best illustrated in FIGS. 1
and 2, the
upper and lower edges of the panels 22 and the columns 24 also merge directly
into
the upper and lower bumpers 16_a and 16b, respectively.
Preferably, the deepest inset portion 26 of each panel 22 is inset into the
container 10 an equal pre-determined distance to the most outwardly projecting
portion of each column. For example, if each panel 22 is inset approximately 2
mm
from an imaginary container datum plane "D" as-formed, then each column
projects 2
mm from the container datum plane "D" as-formed. The "container datum plane
'D"'
is defined as an imaginary cylindrical plane about which the panels bow
inwardly and
about which the columns bow outwardly. See the dashed line "D" in FIG 4.
In another embodiment, which provides certain additional structural and
functional advantages over the first-described embodiment, is illustrated in
FIGS. 5-9.
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The container 1 10 includes a base I 14, a sidewall 1 16 and a dome 112 having
a finish
118. In this embodiment, each column, such as the column 124, has an hourglass-

shape in vertical elevation, with its narrowest region located at the vertical
median of
the sidewall 116 as determined by section line 7--7. From there, the column
flares
outwardly in both upward and downward directions. Each panel 122 between
adjacent columns 124 is complementary and has its widest portion at the
sidewall
median and narrows therefrom in both upward and downward directions. Both the
columns and the panels merge smoothly outwardly with the upper and lower
bumpers
116a and 1 16b_, respectively.
In this embodiment, each of the finger grip protrusions 132, as discussed
below, is of equal size, shape and radial extent providing better grip-ability
without
sacrificing flexural performance.
When the containers 10, 1 10 are hot-filled with a beverage, each panel 22,
122
initially deflects outwardly slightly, as best shown for container 110
exaggerated in
dot-dash line in FIG. 6, to increase the volume of the containers 10, 110.
After the
containers 10 and 1 10 are hot-filled, capped and permitted to cool, each
panel 22, 122
deflects inwardly to effectively reduce the volume of each container 10 and
110, as
best illustrated greatly exaggerated for container 110 by the dashed lines in
FIGS. 6
and 7-9.
Each of the columns 24, 124 also reacts to the forces created in the hot-
filled,
capped and cooled containers 10 and 1 10. In horizontal cross-section, the
convexity
of each column 24, 124 increases due to the lateral pinching of the inwardly
deflecting
adjacent panels 22, 122. In vertical cross-section, each column 24, 124
straightens.
The combination of the lateral pinching and the vertical straightening creates
more
column structure as more vacuum develops in the container. The increase in
column
structure increases the post strength provided by the columns 24, 124 and
provides
the filled and capped containers 10 and 1 10 with increased top loading
capability. The
intended altered shape of the columns 24, 124 also aids in resisting unwanted
container distortion and provides enhanced visual aesthetic interest in the
container.
Note the deflection relative to the container datum plane "D" in FIG. 7.
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Preferably, each column 24, 124 is provided with a plurality of vertically
aligned protrusions 32, 132 on about one inch centers. In vertical elevation,
the
protrusions are defined by laterally undulating lines of inflection 34, 134
and radially
undulating surfaces 36, 136. The outward extent of the radially-undulating
surfaces
S 36 may vary in radial extent, from maximum at the top to minimum at the
bottom,
such as illustrated in FIG. 1, or may be of equal extent such as illustrated
in the
embodiment of FIG. 5. The outward protrusions 32, 132 define therebetween
valleys
38, 138 affording finger placement locations to improve gripability of the
container.
The pattern of protrusions 32, 132 also provides visual interest and
structurally
reinforces the columns 24, 124 at certain desired locations while affording
the desired
flexure at certain other desired locations.
The present invention is particularly suited for use in slender bottles, ie.
bottles
having a predetermined slenderness ratio. Slenderness ratio as used herein is
the
length of the bottle 10, of FIG. 1, measured axially from the upper edge 18_a
of the
finish 18 to the bottom of the standing ring 14a of the base 14 divided by the
mean
diameter of the sidewall 16, or body portion, located between the bottom of
the dome
12 and the base 14. In the illustrated bottle 10, the slenderness ratio is
3.3:1. The
bottle 10 is drawn to full scale. In has an overall length of about 22.9 cm (9
inches)
and a 0.7 liter (24 ounce) filled capacity.
By way of example, and not by way of limitation, each bottle, such as the
bottle 10, may be designed to contain between about a 0.2 liters (about 8
ounces) to
about 1.9 liters (about 64 ounces) of a beverage. The sidewall 16 may include
any
number of panels 22, 122 and columns 24, 124, such as in a range of two
through ten.
The deepest inset portion 26 of each panel in the as-formed condition of the
container
relative to the container datum plane "D" is about I to about 4 mm. The
circumferential groove 20 in the dome 12 is approximately 6 to 7 mm in depth
and
approximately 4 to 5 mm in height. The filled and capped containers 10 are
capable
of being packed and shipped in an efficient amount of space because the panels
22 of
one container's sidewall interdigitate with the columns 24 of the adjacent
containers
to minimize packing volume.
8



CA 02370320 2001-11-06
WO 00/68095 PCT/US00/12625
A third embodiment of the present invention is provided by container 210 as
illustrated in FIGs. 10 and 11. The hot-fillable plastic container 210 has a
dome 212
with a finish 218, a lower sidewall 216 adjacent a base 214, and a
substantially
cylindrical intermediate sidewall 234 to which a label (not shown) can be
secured.
The lower sidewall 216 includes six vertically- elongate unframed flex panels
222 in
an alternating array with six vertically-elongate columns 224 which, when hot-
filled,
function similar to the unframed flex panels and columns as disclosed above
for
containers 10 and 1 10.
Thus, the present invention provides a hot-fillable container which integrates
various functional and aesthetic features without clearly segregating the
features.
Unframed panels and columns interact to provide vacuum absorption functions
and
structural reinforcement functions. As more vacuum develops in the container,
greater structural functions develop in the container sidewall to provide a
container
which is functional, structurally strong and visually aesthetic.
Various modifications to the container are contemplated. For instance, such
modifications may include the use of an odd or an even number of panels,
vacuum
absorption and structural zones located in the dome of the container, and
finger grips
provided by indentations instead of protrusions.
While preferred embodiments of containers having a sidewall with unframed
flex panels have been described, various modifications, alterations, and
changes may
be made without departing from the spirit and scope of the present invention
as
defined in the appended claims.
9

Representative Drawing