Note: Descriptions are shown in the official language in which they were submitted.
SPECIFICATION
Brief Description of the Prior Art
. Patch top container and methods of making the same are
. well known in the patented prior art, as evidenced, for example,
by the patents to Asmus et al Nos. 3,501,045 and 3,734,044, and
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Johnson et al l~o. 3,892,351, and the ~3estphal et al Patent No.
3,961,566 (which is assigned to the same assignee as the instant
invention).
In these prior patents, the end of a container (which is
normally of the composite type including layers of paperboard,
rOil, synthetic plastic material or the like) is closed by a
relatively thin patch top member (normally formed from aluminum
foil or the like). T~e patch top member is bonded to the con-
tainer end ~for e~ample, by a heat sealable membrane, a hot melt
adhesive, an ethylene vinyl acetate adhesive, or the like) to
afford an hermetically sealed container. A reusable synthetic
plastic overcap is then provided for protecting and maintaining
in place the patch top member. As is conventional in the art,
pull tab means are provided on the patch top members so that
~hen the plastic overcap is removed to expose the patch top, the
pull tab portion of the patch top member may be manually grasped
by the user to remove the patch top from, and thereby open, the
container. The patch top member is then discarded, and the
packaged contents may be removed from the container. If desired,
the container may be reclosed by the reapplication of the
plastic overcap to the container.
SVI~MARY OF THE INYENTION
_ .
In general terms, the present invention provides
composite container closure means that are initially in a bonded
condition to afford an hermetically sealed closure for the
container, and which~are subsequently operable to afford means
for reclosing the container. In one embodiment, the synthetic
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;~ stic overcap member is dilectly bonded to tihe container end,
an~ is also removably connected with the container for the
reapplication thereto. In a second embodiJnent, a patch top
member is bonded to the plastic overcap for simultaneous removal
therewith. In this manner, the possibility of undesirab]e
litter normally produced by the removal of the patch top member
is eliminated, and since the patch top member is always protected
and/or supported by the overcap member, it may be formed of a
thinner gauge aluminum foil, ~hereby the cost Or the resulting
O container is reduced. Furthermore, the necessity of providing
pull tab me2ns on the patch top member and the manufacturing and
assemb]ing considerations resulting therefrom are eliminated.
In a primary aspect of the present invention a ~-`
method and closure means for a container is provided, including
.5 a synthetic plastic overcap member extending transversely across
the reversely curled open end Or a composite container, means
bonding the overcap member in hermetically sealed relation to
the curled end, and means releasably connecting the overcap
member with the body member, whereby when the overcap member is
.0 rernoved from the body member end, the hermetically sealed bond
is automatically broken and access ~s afforded to the interior
of the container, whereupon the overcap member may be reapplied
to close the container end. In a first embodiment, the synthetic
plastic overcap member is directly bonded to the curled container
?5 end, said overcap member being provided with means for removably
connecting the overcap with the container. In a second embodi-
ment, the overcap is bonded to the container end by means of a
patch top member which is bonded between the overcap and the
container, respectivelY, said patch top being connected wi~th
the overcap member for the simultaneous removal from the con-
tainer therewith.
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According to anotheraspect ol the invention, a~ improved
patch top container is provided including a patch top member
seated across the open end of a container, a plastic overcap
mounted on the contalner end in protective relationship above
the patch top member, first adhesive means bonding the patch
top member in hermetically sealed relation to the container
end, and second adhesive means bonding ~he patch top member
to the overcap member, the second adhesive means having a greater
bonding strength than the first adhesive means, whereby the patch
) top member will be automatically removed from the container
simultaneously with the plastic overcap member.
In accordance with a more specificfeature of the invention,
the plastic overcap of either embodiment includes a central por-
tion which extends slightly into the container end, and an
intermediate portion containing an annular groove or recess which
has a configuration which conforms generally to the inner
circumferential surface of the container end. In the patch top
embodiment, the patch top me~nber has a transverse central portion
which is axially displaced from the extremity Or the container
end, and an annular peripheral portion which is pressed in con-
forming relation against the inner circumferential surface of
the reversely curled portion of the container end.
In accordance with a further feature of the invention, the
container is Or the composite container type including a fibrous
body wall layer and at least one impervious liner layer, the end
of the container being reversely outwardly curled to define a
curled end portion. The plastic overcap member fur~her includes
an annular flange portion that extends concentrically about the
container end portion, said flange portion carrying on its inner
O surface locking means which engage the container curled portion
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to retain the o~ercap on the container, and also to ~ias the
overcap intermediate portion in a direction causing conforming
en~agement of the patch top peripheral annular portio~ with the
inner end surface of the container.
_ A further object of the invention is to provide a patch
top container assembly of the type described above including
tfimper-proof means for resisting the removal of the plastic
overcap member ~rom the container; more particularly, a con-
ventional s~rink tape member is shrunk-fit about the outer .
circumference of the end portion of the container across the
juncture between the free end of the flange portion of the plasti
overcap and the adjacent outer surface of the container.
Accor~ing to another f~ef the invention, a metho~ for
forming a patch top container is provided which includes the
steps of removably connecting an overcap member to the reversely
curled end of a composite container, and bonding the overcap
member to the container end to define an hermetic seal, whereby
upon removal of the overcap, the seal is automatically broken,
and the overcap may then be reapplied to the container. Accord-
ing to an embodiment of the ~nvention, a patch top member is
arranged between the container and overcap member, the patch
top member being bonded to the container by a first adhesive
material affording a relatively weak bond, and to the overcap
member by a second adhesive material affording a relatively
strong bond, whereby ~hen the overcap member is removed, the
bond afforded by the first adhesive material is broken, and the
patch top member is removed from the container simultaneously wit
the overcap member. In either embod~iment, a synthetic plastic
tape may be shrunk-fit about the ~unction between the f~ange
portion of the overcap member and the outer surface o~ the
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container, thereby to resist unintentional removal of the
overcap member.
BRIE~ DE-SCRIPTION OF ~HE F~GURES
Other objects and advantages of the invention will become
apparent from a study of the following specification when viewed
; in the light of the accompanying drawing, in which:
Fig. 1 is a detailed side elevational view of a
composite container provided with the patch top closure
means of the present invention;
Figs. 2 and 3 are side elevational and top plan views
of the synthetic plastic overcap member of the embodi-
; ment of Fig. l;
Fig.-4 is a detailed sectional view taken along line '
4-4 of Fig. 2;
Fig. 5 is a detailed sectional view of a modification of
the invention of Fig. l;
Fig. 6 is a detailed sectional view of a second modi-
fication Or the invention of Fig. 1;
Fig. 7 is a detailed sectional view of a second embodi-
ment of the invention; and
Fig. 8 is a detailed sectional view of a modification
of the invention of Fig. 7.
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DETAILED DESCRIPTION
Referring now more particularly to Fig. l, the container
assembly includes a tubular composite body wall 2 having a fibrous
body wall 2a to the inner and outer surfaces of which are bonded
impervious inner and outer liner layers 2b and 2c, respectively,
which are normally formed from relatively thin gauge aluminum
foil. The open end of the container body wall is reversely
curled to define the curled end portion 2d. Seated across the
open end of the container body wall 2 is a patch top member 4
which is of a uniform disk-shaped configuration (i.e., without the
pull-tab means normally provided on such patch top closure members) .
The patch top member normally includes a layer 4a of aluminum
foil the inner and outer surfaces of which are coated with first
and second layers of adhesive means 4b and 4c, respectively.
Mounted in protective relation upon the end of the con-
tainer 2 above the patch top member 4 is an overcap member 6
which is preferably formed of a synthetic plastic material. The
plastic overcap member 6 includes a central portion 6a which
extends slightly within the container body wall 2, an intermediate
portion 6b which contains a concave recess 8 for receiving the
curled end portion 2d of the container, and a flange portion 6c
that extends concentrically about the container end. As shown
in Fig. l, the central portion 6a of the plastic overcap causes
displacement of the central portion 4d of the patch top member
axially within the container. The inner wall surface of the
recess of the intermediate portion 6b of the plastic overcap con-
forms generally with and is spaced from the configuration of the
reversely curled end portion of the container body 2. Thus, the
annular peripheral portion 4e of the patch top is caused to conform
with the inner circumferential end portion of the container 2 by
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the curved wall portion of the recess 8 contained in the inter-
mediate portion of the plastic overcap. Furthermore, in order to
maintain the plastic overcap on the container, the flange portion
6c of the overcap member is provided on its inner surface with an
annular locking rib 6d which extends in snap-fit relation beneath
the lower extremity of the container curled end portion 2d.
Preferably the cavity or recess 8 is so dimensioned that the lock-
ing of the rib 6d beneath the curled portion 2d causes the applica-
tion of a biasing force in the direction indicated by the arrow F,
which biasing force causes the peripheral annular portion 4e of the
patch top member 4 to be maintained in conforming engagement with ,
the corresponding surface on the container end.
In accordance with the present invention, the second
adhesive layer 4c for bonding the paich top 4 to the overcap 6 is
stronger than the first adhesive layer 4b which adhesively bonds
in an hermetically sealed manner the patch top member 4 to the
container 2. Thus, the second adhesive layer 4c is selected
which has a relatively high bonding strength, as for example, a
heat-sealable layer of polyethylene, or the like. The first
adhesive layer 4b is selected having a relatively low bonding
strength, as, for example, a peelable hot melt adhesive, a layer
of ethylene vinyl acetate, or a suitable pressure-sensitive
adhesive layer. Although the first adhesive layer 4b has been
illustrated as extending continuously across the inner surface of
the patch top member, if desired it could be provided only adjacent
the annular peripheral portion 4e of the patch top. In either
case, the first adhesive layer provides an hermetiG seal for the
container for the container contents.
In order to assist in ~e removal of the plastic overcap,
there is provided a pull tab portion 6e which extends downwardly
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from the flange portion 6c longitudinally of the container, said
pull tab portion containing an opening 6f. In order to resist
removal of the plastic overcap from the container, tamper-proof
means in the form of a shrink-fit tape 10 are provided, said tape
being wound circumferentially about the container across the
junction between the flange portion 6c of the overcap and the body
wall 2 of the container, said shrink-fit tape including a pull tab
portion 10a for the removal thereof from the container. The
shrink-fit tape is conventional in the art (as evidenced, by the
Minnesota Mining & Manufacturing shrink-fit tape No. Y6887).
Referring to Figs. 2-4, it will be seen that the synthetic plastic
overcap member 6 -- which is preferably formed from low density
polyethylene or the like -- is of flexible unitary molded con-
struction. If desired, the upper surfacec~ the plastic overcap
member may be provided with radially extending reinforcing ribs 6g.
It will be apparent from Fig. 4 that the recess 8 eontained in the
intermediate portion 6b of the plastie overcap 6 has a configuratic n
to conform with that of the curled end portion 2d of the container
body 2.
l
1,
OPERATION
In operation, to open the container package of Fig. 1, the
pull tab portion 10a of the shrink-fit tape 10 is pulled to remove
the tape from the eontainer package, whereupon the tab portion 6e
of the plastie overcap is lifted to pull the overcap member 6
upwardly from the eontainer. During this removal of the plastie
overcap member, the weaker adhesive bond 4b between the patch top
4 and the conforming portion of the inner circumferential surface
of the eontainer end portion 2d is broken, so that the patch top 4
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is removed from the container 2 simultaneously with the removal
of the plastic overcap member 6. The contents may then be
removed from the container 2. In the event it should be desired
to reclose the container, the plastic overcap member 6 -- with
the patch top member 4 secured thereto -- is reapplied to the
container 2 in the illustrated position with the locking rib 6b
again extending in snap-fit relation beneath the curled container
end portion 2d.
It is possible, of course, to further prevent litter by
forming the removable shrink-fit tape lO from a suitable bio-
degradable material, as is known in the art.
Referring now to the alternate embodiment of Fig. 5, it
will be seen that the shrink-fit tape lO' may extend at its upper
extremity lOa' upon the upper marginal portion of the plastic
overcap member 6, thereby to more positively secure the overcap
member to the composite body wall 2.
In accordance with the method of the present invention,
the end portion of the composite containeris reversely outwardly
curled in a conventional manner (for example, as illustrated in
the Ellerbrock Patent No. 3,882,763). The patch top member 4
having the adhesive layers 4b and 4c thereon is preferably
introduced into the plastic overcap (for example, during the
punching operation by which the patch top member is formed from
an aluminum foil sheet, as disclosed in the aforementioned
Westphal et al Patent No. 3,961,566), and to ~e end of the
container with the locking shoulder 6d extending in snap-fit
relation beneath the lower extremity of the container reverse
curl 2d. Thus, the central portion 4d of the patch top is dis-
placed axially within the container and the peripheral annular
portion 4e of the patch top is caused to conform with the inner
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circumferential surface of the curled end portion 2d of the
container body member 2. The end of the container is then heated
(for example, by conventional ultrasonic, induction or dielectric
heating techni~ues) to effect bonding of the patch top member to
the container and to the overcap member by the heat-responsive
layers 4b and 4c, respectively. Thus, in the case where the second
adhesive layer 4d comprises a layer of conventional hot melt
material arranged at least on the peripheral annular portion of
the patch top, the layer is softened by the application of heat
to effect a bond between the patch top member and the container
which is weaker than the bond between the patch top and the plastic
overcap member. The shrink-fit tape 10 is then wound upon the
container, and the container is passed through a separate oven
to effect shrinking of the tape in tight engagement across the
juncture between the lower edge of the flange portion 6c and the
outer surface of the container body. The overcap member is thus
connected against inadvertent displacement relative to the con-
tainer.
Of course, various means may be provided for applying the
first and second layers of adhesive. For example, the second
layer of adhesive 4d could be coated on the inner circumferential
surface of the reversely curled portion 2d prior to the mounting
of the patch top 4 upon the open end of the container. Further-
more, it might be desirable to bond the patch top member 4 to the
plastic overcap member 6 prior to the assembly of the plastic
overcap 6 upon the curled end portion 2d of the container 2.
Finally, as shown in Fig. 5, the central portions of the
overcap and patch top members 6 and 4', respectively, may be
flat and horizontal, the patch top member extending in contiguous
engagement across the upper extremity of the reversely curled
container end.
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In the modification of Fig. 7, the patch top member is
omitted, the synthetic plastic overcap member 106 (of low density
polyethylene, for example) being bonded directly to the reversely
curled end portion of the body member 102 (for example, by con-
ventional ultrasonic or dielectric techniques). In this embodi-
ment, the central portion 106a of the plastic overcap member
extends axially slightly within the container end, and in the
embodiment of Fig. 8, the inner surface of the plastic overcap
member is flat and horizontal and extends in contiguous engagement
across the upper extremity of the reversely curled container end.
In both embodiments, the snap-fit locking shoulders 106d and 106d'
serve to bias theinner surface of the overcap member against the
upper extremity of the container during the bonding operation.
In the embodiments of Figs. 7 and 8 (as in the embodiments
f Figs 1-6), the hermetic seal is automatically broken during
the removal o~ the plastic overcap, the overcap then being
suitable for reapplication to the container.
Whlle in accordance with the provisions of the Patent
Statutes, the preferred forms and embodiments of the invention
have been illustrated and described, it will be apparent to those
skilled in the art that various improvements and modifications
may be made in the described apparatus without deviating from the
inventive concepts set forth above.
