Note: Descriptions are shown in the official language in which they were submitted.
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L.~lINATED PAPERBOARD CONTAINER WITH
ABSORPTION RESISTA~CE MEANS, A~D
BLANK FOR CONSTRUCTING SAME
05 Technlcal Field
This invention relates generally to paperboard
containers and, more particularly to a laminated wall
construction for same, including oil, sreas , and solvent
resistant barriers or layers.
lS Background Art
Various industries have found that central packaging
for distant markets is a beneficial approach in their
business activity and can assist them in developing
strong market bases. With the increased emphasis on
volume producing and marketing, manv centers of
population in reference to a produc. market base may
extend across international bou~daries. Thus, out of
both necessity and convenience, situations have developed
where essential produ~tion marketing areas extend across
vast market areas. Hence, longer shelf life for
difficult to contain liquids, such as edible oils and
motor oil products, is needed so that producers and
suppliers can provide uniform top quality merchandise
throughout their areas of distribution~
It is well known to include a layer of aluminum
foil, which generally serves as a means of preventing
oxygen and ultra violet light rays from penetrating
through the walls of a paperboard container. ~owever,
when the product being packaged is an edible oil or other
oil product, additional precautions must be taken to
assure a total resistance to penetration or staining
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through the wall of the paperboard container to the
outside surface over a long shelf life.
Disclosure of the Invention
05
Accordingly, a general ob~ect of the invention is to
provide an improved, economical paperboard container
which is capable of improving the shelf life of oils.
Another object of the invention is to provide a
container having an improved wall construction of
suitable oil and grease resistant barriers or layers
which are compatible with one another insofar as bonding
and sealing are concerned.
A further object of the invention is to provide a
paperboard container for retaining edible oils and other
type oils, wherein the wall construction includes a
suitable combination of layers of thermoplastic material,
such as polyethylene, iono~ers, such as surlyns, and
aluminum foil, in conjunction with bleached or
unbleached, and suitably treated paperboard material, so
as to bond to one another, seal properly after filling,
and be resistant to staining on the outside .hereof over
an extended shelf life.
These and other objects and advantages of the
invention will be apparent when reference is made to the
following description and accompanying drawings, wherein:
Brief Description of Drawings
Figure 1 is a layout view of the inside surface of a
container blank body, to which the present invention
could be adapted;
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Figure 2 is a flat side seamed blank made from the
container blanX shown in Figure 1, and showing the
outside surface thereof;
05 Figure 3 is a perspective view of a container
fabricated from the blan~s shown in Figures 1 and 2;
Figure 4 is a fragmentary cross-sectional view
through a side panel taken on line 4-4 of Fisure 3, and
looking in the direction of the arrows; and
Figure 5 is a figure similar to Figure 4, showing an
alternate embodiment of the invention.
Best Mode of Caxrying Out the Invention
Referring now to the drawings in greater detail,
Figure 1 illustrates the inside surface of a container
blank 10. The container blank 10 is separated into three
general groups by staggered score lines 12 and 14. The
group above staggered score line 12 is referred to as top
closure group 16. The group between staggered score
lines 12 and 14 are referred to as body group 18. The
group below staggered score line 14 is referred to ~s
bottom closure group 20. The container blank 10 is
defined on its sides by side edges 22 and 24 and is
separated vertically by a series of score lines 26, 28,
30 and 32. The score lines 26, 28, 30 and 32 divide the
group body 18 into side wall panels 34, 36, 38 and 40 and
side seam flap 42.
The top closure group 16 is mounted on the upper end
of body group 18. Triangular end panels 44 and 46 are
mounted to upper ends of the side wall panels 34 and 38,
respectively. The triangular end panel 44 l~as a pair ol
adjacent fold-bac~ panels 48 and 50 mounted on i~s upper
sides and the triangular end panel 46 has a pair ~f
fold-back end panels 52 and 54 ~ounted on its upper
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sides. A pair of inner rib panels 56 and 58 are mounted
adjacent the fold-back panels 48 and 50, respectively. A
pair of inner rib panels 60 and 62 are mounted adjacent
the fold-back panels 52 and 54, respectively.
05
A pair of roof panels 64 and 66 are mounted to the
body group 18 at the upper end of the wide wall panels 36
and 40, respectively. A pair of outer sealing rib panels
68 and 70 are mounted at the upper end of the roof panels
64 and 66, respectively. ~ top edge member 72 defines
the upper free end of top closure group 16. A complete
description of the top closure group 16 is not necessary
to understand the principles of the present invention.
However, reference is made to U.S. Patent 3,270,940 which
issued September 6, 1966 for a complete description of a
top closure group similar to top closure group 16.
The bottom closure group 20 is mounted on the lower
end of body group 18. A tuck-in flap 74 and a tuck-out
flap 76 are mounted at the lower ends of the side wall
panels 34 and 38, respectively, along the staggered score
line 14.
A first minor flap 78 and second minor flap 80 are
mount~d at the bottom of the side wall panels 36 and ~0,
respectively, along the staggered score line 14. A pair
of fold-back panels 82 and 84 connect the first minor
flap 78 to the tuck-in flap 74 and the tuck-out flap 76,
respectively. The second minor flap 80 is connected to
the tuck-out flap 76 and the side seam flap 42 by
fold-back panels 86 and 88, respectively.
A bottom edge member 90 defines the free end of the
bottom closure group 20. The bottom edge member 90 is
substantially defined by three sections at the bottom
edge of the tuck-in flap 74. These three sections or
portions are defined by a cam edge 92, a straight ed~e 9
and a cam edge 96. The bottom edge member 90 is defined
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as an edge portion 98 along the free edge of fold-back
panels 82 and 84. The tuck-out panel 76 has its bottom
edge member 90 defined by a free edge portion which is
substantiaily an extension of the score line 28, a
05 straight edge 100 and a diagonal edge 102. The free edge
portion of the fold-back panels 86 and 88 is defined by
an edge portion 104. The side seam flap 42 has its
portion of ~he bottom edge member 90 defined by a
diagonal edge 106.
When the container blank 10 is being prepared for
assembly as a container it will be side seamed by having
the roof panel 66, the side wall panel 40 and the second
minor flap 80 and its associated fold-back panels 86 and
88 along with the side seam flap 42 folded about the
score line 30 moving their inside surfaces into contact
with the inside surfaces of the triangular end panel 46,
the side wall panel 38 and the tuck-out flap 76 and the
side seam flap 42's inside surface extending past the
score line 28.
The triangular end panel 44, the side wall panel 34
and the tuck-in flap 74 will be rotated about the score
line 26 so their inside surfaces will move toward ~he
inside surface of the roof panel 64, the side wall panel
36 and the first minor flap 78 and the fold-back panels
82 and 84. The side edge 22 will then be substantially
aligned with the score line 32 and its associated ~dge
portion will be aligned with and in contact with the
outside surface of the side seam flap 42. The outside
surface of side seam flap 42 is secured to the inside
surface of the various panel and flap members being
positioned along the side edge 22. This can be
accomplished in many ways. One of the preferred methods
is heat sealing which will establish a surface bond
~, between the above stated members. The container blan~ 10
can then be opened into tubular form as illustra~ed in
Figure 3 as a tubular container member 108.
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In normal production operations the bottom closure
group 20 will be closed and sealed, the contents will be
passed into the tubular container member 108 and then the
top closure group 16 will be closed, as illustrated in
05 Figure 3.
The forming of the side seam blank and the closlng
of the top closure group is covered in detail in the
above mentioned U.S. Patent 3,270,940. The diagonal edge
106 and the diagonal edge 102 are provided so that when
the container is constructed there will not be an extra
layer of paper as the tuck-out flap 76 will not extend
over the side seam flap 42 when the bottom closure group
20 is in constructed form. This is covered in detail in
U.S. Patent Nos. 3,120,335 and 4,341,340.
Referring now to Figure 4, wherein a cross-sectional
view of the wall of the container wall is represented, an
arrow I identifies the inside surface of the container
108, and an arrow O identifies the cutside surface of the
container 108. The identification of the progressive
layers from the inside to the outside is as follows. A
uniform layer 110 is the inside coating, which consists
of a suitable thermoplastic material, such as a low
density polyethylene. A layer 112 consists of a selected
sodium ionomer type surlyn. Such surlyn is selected for
its oil resistant quality. The next layer 114 is the
paperboard material which is the main ma'erial of the
container 108 body. A layer 116 consists of a suitable
adhesive means, such as a zinc ionomer type surlyn, and
serves to bind a layer 118 of aluminum foil to the
outside surface of the paperboard layer 114. The
aluminum foil layer 118 serves not only as an attractive
outer appearance, but also as a barrier means to prevent
the transfer therethrough of any stains from oils,
greases and solvents. This layer may, if desired,
consist of a matalized polyester, in lieu of aluminum
foil. Next is another adhesive layer 120 which may be a
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zinc ionomer type surlyn. Finally, a layer 122 of low
density polyethylene, like the inside layer 110, forms a
uniform outside coating or barrier.
05 Figure 4 is not drawn to scale, and the following
are examples of ranges of suitable weights per square
meter of the material of the respective layers which
could be used in a practical embodiment of a container in
accordance to the invention: layer 110 = 20 to 35 grams
(.00085"-.00142"), layer 112 = 30 io 40 grams
(.00125"-.00167"), layer 114 = 250 to 550 gram~
(.0123"-.0254"), layer 116 = 10 to 15 gra;ns
(.00042"-.00063"), layer 118 = 16 to 25 grams
(.00024"-.00037"), layer 120 = 12 to 17 grams
(.00050"-.00075"), and layer 122 = 12 to 17 grams
(.00050"-.00075"). A specific combination which has been
found to be satisfa~tory for a quart or liter size
container consists of an inside polyethylene layer 110 of
25 grams per square meter, a sodium ionomer type surlyn
layer 112 of 40 grams per square meter, a paperboard
layer 114 of 320 grams per square meter, an intermediate
zinc ionomer type surlyn layer 116 of 15 grams per square
meter, an aluminum foil layer 118 of 25 grams per square
meter, another zinc ionomer type surlyn layer 12Q of 15
grams per square meter, and an outside polyethylene layer
122 of 15 grams per square meter, for a total weight of
455 grams per square meter. For a half pint or 250
milli-liter size container, the layer 110 is preferably
20 grams per square meter, and the layer 114 is 250 grams
per square meter; for a pint or 500 milli-liter size, 20
for layer 110 and 275 for layer 114; for a one half
gallon or 2 liter size, 30 for layer 110 and 475 for
layer 114; and for a gallon or 4 liter size, 35 for iayer
110 and 540 for layer 114.
For some oil product applications it may be
sufficient to omit the aluminum foil layer 118 and the
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adjacent adhesive layers 116 and 120 wi.hout encounterin~
staining on the outside surface.
Additionally, in some applications it may be
05 satisfactory to omit only the zinc ionomer type surlvn
layer 120 (Figure 5), and vary the thicknesses of some or
all the remaining layers. One such arrangement of
layers, as viewed from inside to outside of a container
wall, which tests have shown to be satisfactory, includes
the following weights per square meter: an inside layer
110 of low density polyethylene on the order of 16 grams,
a selected sodium ionomer type surlyn layer 112 on the
order of 50 grams, a paperboard layer 114 ranging between
250-500 grams, depending upon container size,
fluorochemically treated as described below, an
intermediate zinc ionomer type surlyn layer 116 on the
order of 19 grams, an aluminum foil layer 118 of between
16 and 25 grams, and an outside layer 122 of low density
polyethylene on the order of 14 grams. Depending upon
container size, it may be preferable to use layers 110,
112, 116 and 122 varying within the following respective
ranges of weights in grams per square meter: 15-35;
35-60; 10-20; and 12-17.
While the sodium ionomer surlyn and aluminum foil
layers serve to resist penetration and staining by the
confined oil, additionally, the paperboard itself is
treated as described below to assure a high commercial
quality oil container.
For containers o the type describ~d above, the
paperboard consists or paperboard made from virgin pulps,
with such board being either bleached sulphate, or
natural, i.e., unbleached, sulphate, the term sulphate
also being known as "Kraft". When used to contain edible
oils or other oil products, such paperboard may b~
~ treated with fluorochemical paper sizing, such as "2Onyl
RP", a commercially available product of E.I. du Pont de
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Nemours and Company, or "Scotchban", a commercially
available product of Commercial Chemicals Division of 3M
Company, in order to have resistance not only at its
inner cut edges but at all cracks or pinholes to
05 penetration by such oil products. Along with treatment
in this manner, it may be beneficial for the inner cut
edges to be "skived" or folded over in some one of
several known manners, such as that shown and described
in U.S. Patent No. 4,254,693, resulting in a carton edge
structure, as shown in U.S. Patent No. 4,239,150.
Industrial ApPlicability
It should be apparent that the invention provides an
improved paperboard package for carrying oils, greases,
and solvents.
It should also be apparent that the respective
layers of materials described above may be varied in
thickness independently of the other layers to suit
particular liquid packaging applications.
While but two general embodiments of the invention
have been described, other modifications thereof are
possible.
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