U.S. patent application number 12/508757 was filed with the patent office on 2011-01-27 for hot-fillable and retortable plastic container.
This patent application is currently assigned to GRAHAM PACKAGING COMPANY, L.P.. Invention is credited to David A. Brooks, John P. Dinkel, Benton A. Lewis, Jeffrey Snyder, Christie Tyler.
Application Number | 20110017753 12/508757 |
Document ID | / |
Family ID | 42990119 |
Filed Date | 2011-01-27 |
United States Patent
Application |
20110017753 |
Kind Code |
A1 |
Lewis; Benton A. ; et
al. |
January 27, 2011 |
Hot-fillable and Retortable Plastic Container
Abstract
A container made of plastic material, such as PET, that is
adapted to be hot-fillable, retortable and/or pasteurizable. The
container is shaped and formed to appear aesthetically like a
metallic can used typically for storing the types of food found
within the container. The container may have hoops located in the
body portion of the container and have a top portion adapted for
receiving a double-seam can end.
Inventors: |
Lewis; Benton A.;
(Manchester, PA) ; Dinkel; John P.; (York, PA)
; Tyler; Christie; (York, PA) ; Snyder;
Jeffrey; (Dallastown, PA) ; Brooks; David A.;
(Harrisburg, PA) |
Correspondence
Address: |
KNOBLE, YOSHIDA & DUNLEAVY
EIGHT PENN CENTER, SUITE 1350, 1628 JOHN F KENNEDY BLVD
PHILADELPHIA
PA
19103
US
|
Assignee: |
GRAHAM PACKAGING COMPANY,
L.P.
York
PA
|
Family ID: |
42990119 |
Appl. No.: |
12/508757 |
Filed: |
July 24, 2009 |
Current U.S.
Class: |
220/669 |
Current CPC
Class: |
B29C 49/04 20130101;
B65D 1/165 20130101 |
Class at
Publication: |
220/669 |
International
Class: |
B65D 6/02 20060101
B65D006/02 |
Claims
1. A plastic container comprising: a body portion constructed of a
plastic material and comprising a hoop; a base portion located
below the body portion; and a top portion located above the body
portion, wherein the top portion comprises a double seam
structure.
2. The plastic container of claim 1, wherein the body portion
further comprises a plurality of hoops.
3. The plastic container of claim 2, wherein the body portion
comprises three hoops.
4. The plastic container of claim 1, wherein the double seam
structure comprises an upper seam structure and a lower seam
structure, wherein the distance from the central axis of the
container to the upper seam structure is different than the
distance from the central axis of the container to the lower seam
structure.
5. The plastic container of claim 4, wherein the distance from the
central axis of the container to the upper seam structure is
greater than the distance from the central axis of the container to
the lower seam structure.
6. The plastic container of claim 1, wherein the top portion
further comprises an angled edge, which is angled with respect to
the horizontal between 5.degree. to 20.degree..
7. A The plastic container of claim 1, further comprising a double
seam container closure.
8. The plastic container of claim 1, wherein the body portion is
adapted for at least one of hot-filling, a retort process and a
pasteurization process.
9. The plastic container of claim 1, wherein the plastic material
is PET.
10. A plastic container comprising: a body portion constructed of a
plastic material; a base portion located below the body portion; a
top portion located above the body portion; and wherein the body
portion comprises a plurality of hoops.
11. The plastic container of claim 10, wherein the body portion
comprises three hoops.
12. The plastic container of claim 10, wherein the top portion
comprises a double seam structure.
13. The plastic container of claim 12, wherein the double seam
structure comprises an upper seam structure and a lower seam
structure, wherein the distance from the central axis of the
container to the upper seam structure is different than the
distance from the central axis of the container to the lower seam
structure.
14. The plastic container of claim 13, wherein the distance from
the central axis of the container to the upper seam structure is
greater than the distance fiom the central axis of the container to
the lower seam structure.
15. The plastic container of claim 10, wherein the top portion
further comprises an angled edge, which is angled with respect to
the horizontal between 5.degree. to 20.degree..
16. The plastic container of claim 10, further comprising a double
seam container closure.
17. The plastic container of claim 1, wherein the body portion is
adapted for at least one of hot-filling, a retort process and a
pasteurization process.
18. The plastic container of claim 1, wherein the plastic material
is PET.
19. A plastic container comprising: a top portion adapted for
accommodating a closure used with double seam structures; a body
portion adapted for at least one of hot-filling, a retort process
and a pasteurization process, wherein the body portion is located
below the top portion and further wherein the body portion
comprises; a shoulder portion; a first body segment located below
the shoulder portion; a first hoop located below the first body
segment; a second body segment located below the first hoop; a
second hoop located below the second body segment; wherein a height
of the first body segment taken from the shoulder portion to the
first hoop is greater than the height of the second body segment
taken from the first hoop to the second hoop; and a base located
below the body portion.
20. The plastic container of claim 19, further comprising a double
seam container closure.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention is directed to the field of containers
used with food products. In particular the field of the invention
is directed to hot-fillable, retortable and/or pasterurizable
plastic containers.
[0003] 2. Description of the Related Technology
[0004] Plastic blow-molded containers, particularly those molded of
PET, have been utilized in hot-fill applications where the
container is filled with a liquid product heated to a temperature
in excess of 180.degree. F. (82.degree. C.), capped immediately
after filling, and allowed to cool to ambient temperatures. Plastic
blow-molded containers have also been utilized in pasteurization
and retort processes, where a filled and sealed container is
subjected to thermal processing and is then cooled to ambient
temperatures.
[0005] Pasteurization and retort methods are frequently used for
sterilizing solid or semi-solid food products, e.g., pickles and
sauerkraut. The products may be packed into the container along
with a liquid at a temperature less than 82.degree. C. (180.degree.
F.) and then sealed and capped, or the product may be placed in the
container that is then filled with liquid, which may have been
previously heated, and the entire contents of the sealed and capped
container are subsequently heated to a higher temperature. As used
herein, "high-temperature" pasteurization and retort are
sterilization processes in which the product is exposed to
temperatures greater than about 80.degree. C.
[0006] Pasteurization and retort differ from hot-fill processing by
including heating the filled container to a specified temperature,
typically greater than 93.degree. C. (200.degree. F.), until the
contents of the filled container reach a specified temperature, for
example 80.degree. C. (175.degree. F.), for a predetermined length
of time. That is, the external temperature of the hot-filled
container may be greater than 93.degree. C. so that the internal
temperature of a solid or semi-solid product reaches approximately
80.degree. C. Retort processes may also involve applying
overpressure to the container.
[0007] Plastic containers have replaced or provided an alternative
to glass containers for many applications. However, few food
products that must be processed using pasteurization or retort are
available in plastic containers. The rigors of such processing
present significant challenges for the use of plastic containers,
including containers designed for use in hot-fill processing. For
example, during a retort process, when a plastic container is
subjected to relatively high temperatures and pressures, the
plastic container's shape will distort. Upon cooling, the plastic
container generally retains this distorted shape or at least fails
to return to its pre-retort shape. Accordingly, there remains a
need to provide plastic containers that can withstand the rigors of
pasteurization and retort processing in order to take advantage of
the cost savings that can be realized through manufacture and
recycling. The lighter weight of plastic containers as compared to
glass can also advantageously reduce shipping costs.
[0008] Much like glass containers, the usage of metal containers
instead of plastic containers has many disadvantages. Metal
containers may be more expensive to produce and the metal
containers may ultimately weigh more during shipping. Furthermore,
metal containers may dent or be damaged during shipping. Therefore,
the usage of plastic in place of metal would also provide a benefit
for producers of food products that typically use metal
containers.
[0009] While using plastic containers is advantageous in the long
run. The difficulty in producing such a container that also retains
the look and shape of a container that has traditionally held the
type of contents to be stored has proven difficult to achieve.
Therefore there is a need in the field to produce a container that
is able to capture the aesthetic and traditional look of a standard
metal container, such as aluminum cans, while being able to utilize
the benefits of plastic.
SUMMARY OF THE INVENTION
[0010] An object of the present invention is a plastic container
having a double seam structure.
[0011] Another object of the present invention is a plastic
container having hoops located in the body portion.
[0012] Still yet another object of the present invention is a
container having the appearance of a metallic can.
[0013] Another object of the present invention is a container
adapted for hot-filling, a retort process and/or
pasteurization.
[0014] An aspect of the present invention may be a plastic
container comprising: a body portion constructed of a plastic
material and comprising a hoop; a base portion located below the
body portion; and a top portion located above the body portion,
wherein the top portion comprises a double seam structure.
[0015] Yet another aspect of the present invention may be a plastic
container comprising: a body portion constructed of a plastic
material; a base portion located below the body portion; a top
portion located above the body portion; and wherein the body
portion comprises a plurality of hoops.
[0016] Still yet another aspect of the present invention may be a
plastic container comprising: a top portion adapted for
accommodating a closure used with double seam structures; a body
portion located below the top portion, wherein the body portion
comprises; a shoulder portion; a first body segment located below
the shoulder portion; a first hoop located below the first body
segment; a second body segment located below the first hoop; a
second hoop located below the second body segment, wherein a height
of the first body segment taken from the shoulder portion to the
first hoop is greater than the height of the second body segment
taken from the first hoop to the second hoop; and a base located
below the body portion.
[0017] These and various other advantages and features of novelty
that characterize the invention are pointed out with particularity
in the claims annexed hereto and forming a part hereof However, for
a better understanding of the invention, its advantages, and the
objects obtained by its use, reference should be made to the
drawings which form a further part hereof, and to the accompanying
descriptive matter, in which there is illustrated and described a
preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an isometric view of a container, in accordance
with an embodiment of the present invention.
[0019] FIG. 2 is a front view of the container.
[0020] FIG. 3 is expanded view of a section of the container shown
in FIG. 2.
[0021] FIG. 4 is a cross-sectional view of the container taken
along line 4-4 shown in FIG. 2.
[0022] FIG. 5 is a bottom view of the container shown in FIG. 1
[0023] FIG. 6 it a top down view of a double seam container
closure.
[0024] FIG. 7 is a cross-sectional view of the double seam
container closure taken along line 7-7 shown in FIG. 6.
[0025] FIG. 8 is a flow chart showing the steps in the process of
hot-filling, undergoing a retort process and/or pasteurizing the
container.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0026] Referring to the drawings, wherein like reference numerals
designate corresponding structure throughout the views, and now
referring in particular to FIGS. 1 and 2 showing an isometric and
front view of the container 10.
[0027] The container 10 may be a one-piece construction and may be
prepared from a monolayer plastic material, such as a polyamide,
for example, nylon; a polyolefin such as polyethylene, for example,
low density polyethylene (LDPE), high density polyethylene (HDPE),
polypropylene, a polyester, for example, polyethylene terephthalate
(PET), polyethylene naphtalate (PEN), or others, which may also
include additives to vary the physical or chemical properties of
the material. For example, some plastic resins may be modified to
improve the oxygen permeability. Alternatively, the container may
be prepared from a multilayer plastic material. The layers may be
any plastic material, including virgin, recycled and reground
material. The layers may include plastics or other materials with
additives to improve physical properties of the container. In
addition to the above-mentioned materials, other materials often
used in multilayer plastic containers may be used including, for
example, ethylvinyl alcohol (EVOH) and tie layers or binders to
hold together materials that are subject to delamination when used
in adjacent layers. A coating may be applied over the monolayer or
multilayer material to introduce oxygen barrier properties. In an
exemplary embodiment, the present container is prepared from
PET.
[0028] The container 10 is constructed to withstand the rigors of
hot-fill processing, a retort process and/or pasteurization. The
container 10 may be made by conventional blow molding processes
including, for example, extrusion blow molding, stretch blow
molding and injection blow molding. These molding processes are
discussed briefly below.
[0029] In extrusion blow molding, a molten tube of thermoplastic
material, or plastic parison, is extruded between a pair of open
blow mold halves. The blow mold halves close about the parison and
cooperate to provide a cavity into which the parison is blown to
form the container 10. As so formed, container 10 may include extra
material, or flash, at the region where the molds come together. A
moil may be intentionally present above the top portion of the
container.
[0030] After the mold halves open, the container 10 drops out and
is then sent to a trimmer or cutter where any flash of moil
attached to the container 10 is removed. The finished container 10
may have a visible ridge (not shown) formed where the two mold
halves used to form the container came together. This ridge is
often referred to as the parting line.
[0031] With stretch blow molding a preformed parison, or pre-form,
is prepared from a thermoplastic material, typically by an
injection molding process. The pre-form typically includes an
opened end, which becomes part of the closure of the container 10.
The pre-form is positioned between two open blow mold halves. The
blow mold halves close about the pre-form and cooperate to provide
a cavity into which the pre-form is blown to form the container 10.
After molding, the mold halves open to release the container
10.
[0032] With injection blow molding, a thermoplastic material may be
extruded through a rod into an injection mold in order to form a
parison. The parison is then positioned between two open blow mold
halves. The blow mold halves close about the parison and cooperate
to provide a cavity into which the parison may be blown to form the
container 10. After molding, the mold halves open to release the
container 10.
[0033] As discussed above, the plastic blow-molded containers,
particularly those molded of PET, are utilized in hot-fill
applications, retort processes and/or pasteurization. Hot-filling
involves filling the container 10 with a liquid product heated to a
temperature in excess of 180.degree. F. (i.e., 82.degree. C.),
capped immediately after filling, and then allowed to cool to
ambient temperatures. Pasteurization and retort differ from
hot-fill processing by including heating the filled container to a
specified temperature, typically greater than 93.degree. C.
(200.degree. F.), until the contents of the filled container reach
a specified temperature, for example 80.degree. C. (175.degree.
F.), for a predetermined length of time. That is, the external
temperature of the hot-filled container may be greater than
93.degree. C. so that the internal temperature of a solid or
semi-solid product reaches approximately 80.degree. C. Retort
processes may also involve applying overpressure to the
container
[0034] In the construction of containers it is important to keep
the container's top load and hot-fill, retort and pasteurization
performance characteristics strong. The structural integrity of the
container must be maintained after the hot-fill, pasteurization
and/or retort process. Furthermore, consideration must be made for
preventing bulging of the container 10 that can occur with some
containers. When a container 10 is said to be adapted for a
hot-fill process, retort process and/or pasteurization process, it
is meant that the container 10 is designed and structured so as to
withstand the heating and/or over pressuring that are involved in
these processes without undergoing significant structural
deformation.
[0035] Referring to FIGS. 1-5, a cylindrical shaped container 10 is
shown that is similar in appearance to a traditional can. Referring
to FIG. 1, the container 10 has a plurality of hoops 17(a)-17(c)
and a top portion 25, which is a double seam structure adapted to
receive a double seam container closure, also known as a can end.
The container 10 may be used, for example, metal can
replacement.
[0036] The container 10 has a top portion 25 that forms a double
seam structure, which is shown in more detail in FIG. 2. A central
axis A runs through the center of the container 10. The top portion
25 has an opening 16 through which contents are placed. The top
portion 25 also comprises the upper seam structure 19 and the lower
seam structure 18 that forms the double seam structure. The upper
seam structure 19 and the lower seam structure 18 together have a
height H1 that is adapted for receipt of a double seam container
closure. The height H1 is taken from the opening 16 to the top of
the bumper portion 13. In the embodiment shown in FIGS. 1-5 the
upper seam structure 19 and the lower seam structure 18 are
circular in shape.
[0037] Located below the lower seam structure 18 is the bumper
portion 13 comprising a shoulder portion 27 that merges into the
body portion 30 of the container 10. The shoulder portion 27
provides a smooth transition between the bumper 13 and the body
portion 30. The height H2 of the bumper portion 13 may be less than
the height H1 of the top portion 25, however it should be
understood that the height H2 of the bumper portion 13 may vary
depending on the aesthetic design of the container 10. In the
embodiment shown in FIGS. 1-5, the bumper portion 13 is circular in
shape. The bumper portion 13 is adapted to contact the machinery
used to grip the containers 10 used during the line processes, the
bumper portion 13 cooperates with base portion 12 in order to
accomplish this task. The bumper portion 13 also provides
protection for the label placed on the container 10.
[0038] Body portion 30 comprises a plurality of body segments
14(a), 14(b), 15(a), 15(b) and hoops 17(a)-17(c). The body segments
14(a), 14(b), 15(a) and 15(c), shown in FIGS. 1-4 are circular in
shape. Interspersed between the body segments 14(a), 14(b), 15(a)
and 15(c) are hoops 17(a)-17(c).
[0039] The container 10 shown in FIGS. 1 and 2 has a first body
segment 15(a) having a height H3, which is taken from the bottom of
the shoulder portion 27 to the top of the hoop 17(a). Located below
the first body segment 15(a) is the hoop 17(a). Located below the
hoop 17(a) is a second body segment 14(a) that has a height H4
which is the distance between the hoops 17(a) and 17(b) that are
above and below the second body segment 14(a), and is measured from
hoop 17(a) above the second body segment 14(a) to the hoop 17(b)
below the second body segment 14(a). In the embodiment shown in
FIG. 1, the height H3 is greater than the height H4. Located below
the second body segment 14(a) is another body segment 14(b) that
has a height H5 that is substantially the same as the height H4 and
is the distance between the hoop 17(b) to the hoop 17(c). Below the
body segment 14(b) is the hoop 17(c). The body segment 15(b) is
located above the shoulder portion 29 and has a height H6 which is
taken from the hoop 17(c) to the top of the shoulder portion 29.
The height H6 of the body segment 15(b) is substantially the same
as the height H3 of body segment 15(a).
[0040] In the embodiment shown in FIGS. 1-5 there are three hoops
17(a)-17(c) shown, however there may be more or less hoops 17 used
in alternative embodiments depending upon the size of the finished
container 10. It should be understood that the number and types of
body segments may vary depending on the aesthetic requirements of
the container 10. For example, more hoops 17 may be present in the
body portion 30 and therefore there may be more body segments
having the heights of body segments 14(a) and 14(b). Preferably the
heights of the body segments, such as body segments 15(a) and 15(b)
that merge with the shoulder portions 27, 29 are greater than the
heights of the body segments that lie within the central portion of
the body portion 30.
[0041] The hoops 17 further assist in accommodating the stresses
that the container 10 may undergo due to hot-filling, retort
processes and/or pasteurization processes, such as internal
negative pressure. They also assist in preventing buckling,
ovalization and reduction of structural integrity that may be a
result of these processes. While the hoops 17 shown are circular in
shape, it should be understood that other shapes are permissible,
however they may not provide as much structural support for the
container 10 during a hot-fill process, a retort process and/or a
pasteurization process.
[0042] Still referring to FIGS. 1 and 2, located below the body
portion 30 is the base portion 12, which comprises the shoulder
portion 29 and the bottom portion 20. The shoulder portion 29
smoothly merges the base portion 12 into the body portion 30. The
base portion 12 cooperates with the bumper portion 13 in providing
contact points for the machinery used to grip the containers 10
used during the line processes.
[0043] Now turning to FIG. 3, wherein a close up view of the top
portion 25 is shown. Upper seam portion 19 is located above lower
seam portion 18. Merge segment 11 smoothly merges the upper seam
portion 19 into the lower seam portion 18. Between the opening 16
of the container 10 and the upper seam portion 19 is the angled
edge 22. The angled edge 22 is angled with respect to the
horizontal H, which is perpendicular to the central axis A. In the
embodiment shown in FIG. 3 the range of the angle .theta. may be
between 5-20.degree. and more preferably between 10-18.degree., and
still more preferably approximately 14-16.degree.. The angled edge
22 is adapted to receive and facilitate securing a double seam
container closure 40, shown in FIG. 5, which is typically used in
the construction of metal cans. During the placement of the double
seam container closure 40 the angled edge 22 is folded over.
[0044] FIG. 4 shows a cross-sectional view of the container 10
shown in FIG. 2. Illustrated in FIG. 4 are the distances of the
interior surfaces of the container 10 from the central axis A and
in a cylindrical shaped container 10, the distances represented by
the L1-L12 represent the radii at these locations.
[0045] The length L1 is taken from the central axis A to the angled
edge 22. The closure that is placed on the container 10 is
typically of greater length than the length L1. The length L2 is
taken from the central axis A to the interior wall of the upper
seam portion 19. The length L2 is typically less than the length
L1. The length L3 is taken from the central axis A to the interior
wall of the lower seam portion 18 and is typically less than the
length L2.
[0046] The length L4 is taken from the central axis A to the
interior wall of the bumper portion 13. The length L4 is similar to
the length L12. The length L12 is taken from the central axis A to
the interior wall of the base 12. The lengths L4 and L12 are
typically greater than any other lengths of the container 10. These
provide the furthest distances from the central axis A so to
provide contact points on the fill line.
[0047] The lengths L5, L7, L9 and L11 of are taken from the central
axis A to the respective sides of body segments 15(a), 14(a), 14(b)
and 15(b) respectively. The lengths L5, L7, L9 and L11 are all
substantially equal to each other and provide a uniform distance
from the central axis A so as to provide a level surface to enable
the placement of a label.
[0048] The lengths L6, L8 and L10 are taken from the central axis A
to the respective sides of hoops 17(a)-17(c). The lengths L6, L8
and L10 are less than lengths L5, L7, L9 and L11. Additionally the
lengths L6, L8 and L10 may substantially be the same length as L3
of the lower seam portion 18. The similarity in lengths between L6,
L8 and L10 and L3 assist in providing additional strength to the
overall structure of the container 10.
[0049] Referring to FIG. 5, a bottom portion 20 of the container 10
is shown. The bottom portion 20 illustrates the cylindrical nature
of the container 10.
[0050] FIG. 6 is a top down view of the double seam container
closure 40. The double seam container closure 40 is secured to the
container 10 through the usage of the double seam structure,
comprising the upper seam portion 19 and lower seam portion 18,
shown in FIGS. 1-4 The container closure 40 may be made of metal,
such as steel or aluminum. It may be possible to construct the
container closure of a plastic material, provided the closure 40
can withstand the rigors of a hot-fill process, a retort process
and/or a pasteurization process.
[0051] FIG. 7 is a cross-sectional view of the double seam
container closure 40 taken along line 7-7. Additionally shown in
FIG. 7 are the closure tabs 42 which are used to engage the double
seam structure on the container 40.
[0052] FIG. 8 is a flow chart showing the steps in the process of
hot-filling, undergoing a retort process and/or pasteurizing the
container 10. In step 102, the container 10 is provided. In step
104 the container 10 is gripped at the bumper portion 13 and base
portion 12. In step 106, the container 10 undergoes hot-filling, a
retort process and/or a pasteurization process of the contents of
the container 10. It is to be understood that when a retort process
is performed and/or a pasteurization process is performed the
container 10 is first filled with the contents. In step 108, a
double seam container closure 40 is placed on the double seam
structure located at the top portion 25 of the container 10.
[0053] It is to be understood, however, that even though numerous
characteristics and advantages of the present invention have been
set forth in the foregoing description, together with details of
the structure and function of the invention, the disclosure is
illustrative only, and changes may be made in detail, especially in
matters of shape, size and arrangement of parts within the
principles of the invention to the full extent indicated by the
broad general meaning of the terms in which the appended claims are
expressed.
* * * * *