Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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1 Stand-Up Bag
Description
5 The present invention relates to a stand-up bag made of a
heat-sealable or weldable plastic sheet material and
adapted to contain liquid and/or pasty products, said
stand-up bag being provided with a dispensing opening and
comprising two substantially rectangular flat sidewall-
10 forming sheet elements sealed to one another along theirlongitudinal margins, a foldable bottom element acting as
a support bottom and adapted to lie between said sidewalls
being interposed between the lower transverse edges, and a
foldable sheet element acting as a top wall and adapted to
lie between said sidewalls being interposed between said
sidewalls adjacent the upper ends thereof.
Stand-up bags made of plastic sheet material are specific-
ally known as disposable beverage packages. Packages of
this type usually terminate in a pointed end and have a
20 f~lling volume of o.2 litres. The sheet material employed
for these beverage packages is provided with a thin
aluminum sheet layer serving amongst other purposes to
stabilize the package. The bottom side is provided with a
support bottom surface permitting the bag to be placed on
25a support after having been opened, without the danger of
- the bag's contents spilling from the dispensing opening or
of the bag toppling over. In beverage packages of this type
the dispensing opening may for instance be determined by a
pierceable weakened wall portion capable of being pierced
30by a drinking straw terminating in a pointed end.
Aside from beverages, sheet bags are also used for filling
them with other liquid or pasty products, for instance
liquid detergents. Sheet bags of this type are especially
used as refill packages.
35In order to impart increased stability to such stand-up bags
comprising a lower bottom wall interposed between the side-
walls, and preferably composed of two wall elements welded
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1 to one another, an additional top wall element is provided
in an arrangement similar to that of the bottom wall.
The basic advantage of such sheet bags can be seen in the
fact that they can be folded extremely flat in their empty
5 state so as to require little space. Particularly stand-up
bags of a greater volume, for instance a volume of up to
two litres, are practically never used for containing
products to be dispensed in individual portions, because
afetr opening the bag, as by cutting off an upper corner
10 portion, it is not ensured that the bag retains sufficient
stability to remain standing when air enters its interior
and the contents have been partially dispensed.
It is an object of the invention to provide a stand-up bag
which is capable of retaining sufficient stability after
its contents have been partially dispensed, and of being
readily handled and conveyed, which can be manufactured in
a simple manner and requires little storage space in its
unfilled state.
20 This object is attained according to the invention by the
provision that the dispensing opening is defined by a
closeable dispenser spout provided at one of its ends with
a flange by means of which it is secured to a top portion
of one of the sidewalls. The closeable dispenser spout
25 permits the contents of the stand-up bag to be dispensed in
- individual portions. The dispenser spout is located at an
upper portion of the sidewalls, so that the stand-up bag
can be placed on its bottom wall in a standing position
without its contents spilling from the opened dispenser
30 spout. To this purpose it is essential that the stand-up
bag has a stable shape, which is ensured by the provision
of the stand-up bag with an additional top wall element
substantially similar to the bottom wall element. The flange
provided at one end of the dispenser spout permits the
35 latter to be sealingly inserted or welded to a sidewall of
the stand-up bag. The flange is preferably in contact with
and sealed to the inner side of the sidewall, with the
dispenser spout projecting through an opening formed in the
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sidewall. The flange should have a width of between 4 mm
and 8 mm, so tha-t a sufficiently large sealing surface is
provided for sealingly bond the flange to the sidewall.
The thickness of the flange should be no more than 2 mm,
so that the wall thickness of the stand-up back is not
unnecessarily increased, particularly with a view to the
space-saving storage of the empty bag in its folded state.
For permitting it to be closed, the dispenser spout should
be provided, preferably at its outer end, with exterior
threads permitting a closure cap to be threaded thereonto.
This construction permits the stand-up bag to be hermetic-
ally closed to thereby prevent any leakage even of highly
fluid contents. As an alternative, the dispenser spout
may be provided with ~uick-stop closure means comprising
for instance radial projections or undercut portions
formed on the outer surface of the dispenser spout and
adapted to have a protective cap clamped thereonto. A
protective cap of this kind can be clamped onto the
dispenser spout and removed therefrom by overcoming a
slight resistance.
In order to permit the interior volume of the stand-up
bag to be used as fully as possible, the dispenser spout
is preferably spaced by no more than 10 mm from the weld
seam formed between the sidewall and the top wall, and
located at a central position between the two weld seams
inter-connecting the two sidewalls.
For the purpose of mass production i-t may be advantageous
to maintain a stock of different types of dispensing
spouts, for instance ones having different diameters at
their ends, which are then sealingly fitted to an aperture
punched in the respective side wall. In order to permit
sidewalls with punched openings of preferably circular
shape and the same diameter to be employed in combination
with different dispenser spouts, the base portion of each
dispenser spout adjacent the flange should be provided
with an auxiliary flange portion having a diameter
corresponding to that of the punched sidewall openings.
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l For facilitating the handling of the stand-up bag, it is
provided with grip openings formed in sidewall extensions
projecting above the top wall. These grip openings, which
may in a preferred simple embodiment for instance be formed
5 by punched slits, are readily accessible at their location
above the top wall. The grip openings may be formed in a
particularly simple manner by punching the sidewalls of' the
bag in its folded state at congruent positions, so that
they are located diametrally opposite one another in the
lO filled state of the bag. For ensuring the uniform distrib-
ution in the sidewalls of traction forces at the location
of the grip openings, the latter may extend substantially
parallel to the weld seam between the sidewalls and the
top wall.
l5 The stand-up bag is composed of pre-cut heat-sealable flat
elements preferably of a twin-layer compound sheet material.
Excellent results are achieved when the layer facing towards
the interior is a polyethylene sheet, and the layer forming
the outer skin, a polyester sheet. The employ of a poly-
20 ethylene sheet in the form of a coextrusion sheet - i.e.
a multiple-layer sheet material - offfers the advantage
that the layer forming the interior wall of the stand-up
bag can be adapted to various requirements in accordance
with the intended use of the stand-up bag. The side of the
25 sheet material to be sealed may thus for instance be formed
of a particularly readily sealable material; a coextrusion
sheet material of this kind also offers the possibility of
achieving an increased stiffness or stability by proper
selection of its composition. The thickness o~ the outwards
30 facing polyester sheet is at least 10 ,um, and preferably
12 ym, while the inwards facing polyethylene sheet or
coextrusion sheet should have a thickness of 80 ym to 200 ym,
preferably a thickness of 100 ,um to 150 ~m. In order to
permit the stand-up bag to be filled with solvent-contain-
36 ing or migration-sensitive products, a thin aluminum sheet
acting as a barrier layer may be enclosed between layers
of' the sheet material, preferably adjacent the inwards
facing layer. This aluminum sheet should have a thickness
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l of between ~ ,um and 12 ,um, depending on the size of the
stand-up bag. An aluminum layer of this kind is effective
for instance to prevent the leakage of solvents through
the walls of the bag or, in the case of migration-sensitive
5 products, the infiltration of oxygen into the bag and thus
into the product.
For achieving optirnum stability or standing ability of the
bag, the latter is advantageously designed so as to assume
a substantially cylindrical shape in its filled state. To
10 this purpose the two sidewalls are cut to a rectangular
shape and sealed to one another along their longitudinal
margins. In this embodiment the bottom wall element and
the top wall element are formed as substantially circular
cuttings. The bottom and top wall elements are welded to
15 the sidewalls of the collapsed or folded bag along respect-
ive semicircular weld seams. As an alternative to the rect-
angular shape of the sidewalls or the cylindrical shape of
the filled bag~ respectively, The sidewalls may be slightly
convergent towards the top wall element, resulting in a
20 frusto-conical configuration of the filled stand-up bag.
An embodiment of the invention shall now be described in
more detail by way of example with reference to the
accompanying drawings, wherein:
2sfig. 1 shows a perspective view of a filled stand-up bag,
fig. 2 shows the stand-up bag of fig. 1 in its empty and
folded state, in a sectional view taken along the
line II-II in fig. 3,
fig. 3 shows a top plan view of the stand-up bag of fig. 1
in its empty and folded state,
fig. 4 shows a sectional view of the dispensing opening
taken along the line IV-IV inlfig. 3, and
fig. 5 shows a sectional view of the plastic sheet material
used for making the stand-up bag.
As shown in figs. 1 and 3, the illustrated stand-up bag has
two sidewalls 1 heat-sealed to one another at their
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1 vertically extending longitudinal margins 2 by respective
sealing or weld seams 3. Interposed between sidewalls 1
along their lower transverse margins 4 is a bottom wall
element 5 acting as a stand-up support bottom and formed
5 as a circular or elliptical cutting as clearly apparent
from the bottom weld seam 6 depicted in figs. 1 and 3.
Bottom wall element 5 and sidewalls 1 are welded to each
other in surface contact over the entire area between
bottom weld seam 6 and lower transverse margins 4, so
10 that the thus obtained twin-layer plastic sheet acts as a
reinforced wall of the lower portion of the bag.
In the filled state of the bag bottom wall element 5
assumes a sagging shape, at least at its central portion,
so that it rests on a support surface on which the stand-up
15 bag is placed. The sagg~ng portion of bottom wall element 5
cooperates with the reinforced lower transverse edges 4 to
impart excellent standing ability to the stand-up bag. One
of the two sidewalls is provided with a dispenser spout 7
at its upper portion.
All of the cuttings used for making the stand-up bag
consist of a twin-layer plastic sheet material of the type
depicted in cross-section in fig. 5. The outwards facing
sheet 8 acting as the outer skin is a polyester sheet hav-
ing a thickness of 12 ,um, while the sheet 10 facing towards
_ the interior 9 of the stand-up bag and acting as the inner
skin is a polyethylene sheet formed as a coextrusion sheet.
A coextrusion sheet of this kind has a multiple-layer
construction which may be varied during the extrusion
process for adaptation to specific requirements in accord-
ance with its intended use. Sheet 10 has a thickness of
150 ~um, the sheet thicknesses stated above being applicable
in the case of a stand-up bag having a capacity of about
1 to 1.5 litres, or a maximum capacity of 2 litres.
Enclosed between sheet 8 acting as the outer skin and
35 sheet 10 acting as the inner skin is a thin aluminum sheet
10' acting as a barrier layer and having a thickness of
between 8 ,um and 12 ~m, depending on the size of the
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l stand-up bag. An aluminum layer of this kind is effective
for instance to prevent the leakage of solvents through
the walls of the bag or, in the case of migration-sensitive
products, the infiltration of oxygen ~nto the bag and
5 thus into the product.
The stand-up bag has substantially cylindrical outer con-
tours in its filled state thanks to the provision of a
top wall element 11 of a shape corresponding to that of
bottom wall element 5 and welded to upper portions of
lO sidewalls 1. By contrast to weld seam 6 of bottom wall 5,
the weld seam 12 of top wall element 11 extends along a
circular-arcuate path with its open side facing downwards,
i.e. it is formed as a mirror image of weld seam 6 of
bottom wall 5. Bottom wall element 5 and top wall element
15 11 are each formed with a folding seam 13 extending between
weld seams 3 of sidewalls 1 as illustrated in fig. 3.
The dispensing opening of the bag defined by dispenser
spout 7 is located adjacent folding seam 13 of top wall 11.
Dispenser spout 7 has its base end provided with a flange
14 by means of which it is sealingly secured to the inner
side of the inwards facing sheet 10. Dispenser spout 7
projects from sidewall 1 of the stand-up bag by about 15 mm
to 20 mm and is closed by a closure cap 15 provided with
screw threads 16. Closure cap 15 may be provided wlth a
_ sealing gasket 17 inserted therein. As indicated in fig. 4,
flange 14 has a width 18 of about 5 mm, and a thickness 19
of about 1.5 mm. The rim of flange 14 is spaced from top
wall weld seam 12 by about 5 mm to 10 mm and located at a
central position between weld seasm 3 of sidewalls 1 inter-
connected at thelr longltudlnal marglns 2.
Sidewalls 1 are extended upwards beyond top wall 11, the
thus extended portions of the sidewalls being of sufficient
length for punchign grip openings 20 therein. In the folded
35state of the stand-up bag illustrated in fig. 3, the grip
openings 20 in the two sidewalls 1 are superimposed at
congruent positions, so that they can be formed in a single
punching operation. By contrast to the grip openings 20
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1 of the stand-up bag shown in fig. 3, in which embodiment
the sheet portions separated by the slit-shaped openings
are pushed aside when the stand-up bag is to be carried,
the grip openings may also be provided in the shape of
5 horizontally extending elongate openings. The grip openings
20 are of an arcuate shape approximately corresponding to
that of top wall weld seam 12. The upper portion of the
stand-up bag between top wall weld seam 12 and the upper
transverse margin 21 may likewise be formed as a twin-layer
10 sheet construction formed by the upper extensions of
sidewalls 1 and upwards folded sections of the cutting
used for forming top wall 11, resulting in a reinforced
structure of the wall portions in which grip openings 20
are located. These reinforced upper wall portions may for
15 instance be provided with an additional perforation 22
permitting the stand-up bag to be suspended from a peg
or the like.