Note: Descriptions are shown in the official language in which they were submitted.
CA 02437936 2003-08-12
Pre-cut sheet and box produced therefrom, in particular for
cigarettes
Description
The present invention relates to a pre-cut sheet and also
boxes produced therefrom, as used in particular as
packaging for cigarettes.
Cigarettes are usually marketed either in soft-pack packs
or in hard-pack packs, for example in flip-top boxes or
hinge-lid boxes, but also in so-called rigid-soft packs
without flip tops. In the case of hard-pack packs it is
also known to round off corners and edges in order to
protect the pockets of the consumer. Thus for example DE 29
40 797 A1 describes for this purpose a cigarette box among
others of hinge-lid type in which all corners and edges are
rounded off. However this German unexamined patent
application does not disclose how this box can be produced.
In EP 0 764 595 A1, a cigarette box of hinge-lid type is
described, the four horizontal main edges of which are
chamfered or rounded off. To produce these edges,
corresponding pre-cut sheets are also shown. This European
publication furthermore contains a reference to US 2 523
251 (lines 51 to 54 in column 4 of EP 0 764 595 A1) and
thus also the combination of the rounded-off or chamfered
horizontal edges of EP 0 764 595 A1 and the chamfered
longitudinal edges of US 2 523 251. Again however there is
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no indication of how this special version is to be
produced.
In fact, the production of a box, in particular a cigarette
flip-top box in which all corners and the longitudinal
edges and horizontal main edges are rounded off or
chamfered, from a single pre-cut sheet is problematic.
The problem of the present invention is therefore to
provide a pre-cut sheet which is simple to produce for the
production of a box, in particular a cigarette box in which
all longitudinal edges and the horizontal main edges and
also the corners are rounded off or chamfered to the
greatest extent possible.
The solution to this problem is a pre-cut sheet made from
foldable material for forming a cuboidal box which is
closed at least on 5 sides, two main surface fields lying
diametrically opposite each other in the cuboidal box to be
formed and a base field connecting them being arranged in
rectilinear succession in the pre-cut sheet and the sides
which, in the cuboidal box to be formed, lie against the
two main surface fields lying diametrically opposite each
other and against the base field connecting these, being
formed by side-surface fields which project laterally from
the two main surface fields, and edges of the two main
surface fields lying diametrically opposite each other in
the cuboidal box to be formed being formed by fold areas,
characterized in that
- two fold areas meet each other at (preferably the
bottom) corners of the two main surface fields lying
~
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diametrically opposite each other in the cuboidal box to be
formed and
- of two fold areas which meet each other (preferably
essentially at right angles) the one is delimited by a
circle arc segment of approx. 45° to 90°, preferably 65°
to
80°, and the other by an S-curve, the S-curve conforming to
the circle arc segment to the corner of the main surface
fields and
- each of the fold areas is preferably formed by two or
more neighbouring, essentially parallel fold lines.
Preferred is a pre-cut sheet as defined above with a first
main surface field with a left- and right-hand first side-
surface field,
- a base field joining up with the top edge of the first
surface field and a second main surface field with a left-
and right-hand second side-surface field joining up with
the top edge of the base field,
- the pre-cut sheet having horizontal and vertical fold
areas, namely a first and second horizontal fold area
between the first main surface field and the base field as
well as between the base field and the second main surface
field and first to fourth vertical fold areas between the
left-hand first side-surface field and the first main
surface field, the first main surface field and the right-
hand first side-surface field, the left-hand second side-
surface field and the second main surface field as well as
between the second main surface field and the right-hand
second side-surface field,
- the first horizontal fold area meeting the first and
second vertical fold areas at the top corners of the first
main surface field and
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- the second horizontal fold area meeting the third and
fourth vertical fold areas at the bottom corners of the
second main surface field.
The pre-cut sheet described above can be produced easily by
appropriate modification of existing machines for the
production of pre-cut sheets. By customary folding and
gluing, a hard-pack pack results therefrom which consists
only of a box part into which a cigarette group wrapped in
an inner liner can be inserted. Usually the box size is
dimensioned such that the cigarette group sits tightly in
the box and projects somewhat at the top, open end of the
box in order to make it possible for the consumer to open
the box and to remove the cigarettes.
As a rule however, in addition to the box part the box will
also have a lid part so that a customary hinge-lid box
results.
In order to obtain this customary hinge-lid box, the pre-
cut sheet described above has additional fields, namely,
joining up with the second main surface field a third main
surface field with a left- and right-hand third side-
surface field, a top side field joining up with the top
edge of the third main surface field and a fourth main
surface field with a left- and right-hand side-surface
field joining up with the top edge of the top side field,
and
- the pre-cut sheet having further horizontal and
vertical fold areas, namely a third and fourth horizontal
fold area between the third main surface field and the top
side field as well as between the top side field and the
CA 02437936 2003-08-12
fourth main surface field and fifth to eighth vertical fold
areas between the left-hand third side-surface field and
the third main surface field, the third main surface field
and the right-hand third side-surface field, the left-hand
5 fourth side-surface field and the fourth main surface field
as well as between the fourth main surface field and the
right-hand fourth side-surface field,
- the third horizontal fold area meeting the fifth and
sixth vertical fold areas at the top corners of the third
main surface field and
- the fourth horizontal fold area meeting the seventh
and eighth vertical fold areas at the bottom corners of the
fourth main surface field.
Advantageously, the pre-cut sheet, in addition to the
fields described, also has supplementary left- and right-
hand second side-surface field end tabs on the bottom edges
of the left- and right-hand second side-surface fields, and
also left-hand and right-hand third side-surface field end
tabs on the top edges of the left- and right-hand third
side-surface fields. These side-surface field end tabs
serve to strengthen the base and the lid of the finished
box.
There is preferably located on the top edge of the fourth
main surface field a strengthening field which, during the
production of the box, is glued to the inside of the fourth
main surface field and likewise serves to strengthen.
The customary materials for hinge-lid boxes can be used as
foldable material, e.g. paper or cardboard, optionally
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coated, and also plastic, plastic film or plastic laminate,
preferably shortgrain paper or shortgrain cardboard.
The fold lines can be either grooves or preferably scoring
lines and preferably extend over the whole length and
breadth of the box.
To produce grooves the relevant points of the pre-cut sheet
are indented by a grooving unit. On the opposite side there
is a groove channel into which the material of the pre-cut
sheet can be pressed. In the case of parallel-running
grooves, a corrugated cross-section results according to
the described process. This process is described for
example in US 2 523 251 and the result shown in Fig. 2
thereof. When the thus-worked pre-cut sheet is folded up,
the round (in the case of several grooves) or chamfered (in
the case of two grooves) edges of the pack then
automatically form along the grooves.
A disadvantage of this is however that, due to the inherent
rigidity and the elastic restoring forces of the pack
material, the gluing for producing the cigarette pack is
not unproblematic. This is usually carried out on
overlapping areas of the pre-cut sheet which form the side
walls of the box. As a result of the rounded-off or
chamfered edges, these overlapping areas are clearly
reduced compared with a normal e.g. hinge-lid box with the
result that only a limited amount of glue can be applied.
As a result therefore, the machine production is slowed
down, as it is necessary to wait longer until the
relatively small amount of glue has dried well as the box
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would otherwise reopen as a result of the elastic restoring
forces of the material.
This is particularly pronounced when shortgrain cardboard
or paper is used for the production of the e.g. hinge-lid
box. In the case of paper or cardboard production, the
product-forming material is placed on a fast-moving belt.
This has the effect that the long fibres in the material
preferably orient themselves in longitudinal direction.
Depending on whether the pre-cut sheet is later cut along
or across the finished material web, the long fibres in the
pre-cut sheet are arranged across the longitudinal axis of
the pre-cut sheet (shortgrain) or along the longitudinal
axis of the pre-cut sheet (longgrain). The result of the
orientation of the fibres across the longitudinal direction
of the shortgrain pre-cut sheet is a good flexibility about
the transverse axis, but a poor flexibility about the
longitudinal axis. The elastic restoring forces for the
lateral gluing are therefore stronger than with longgrain
pre-cut sheets in which, due to the transposed position of
the long fibres in the material, the conditions are exactly
the opposite. On the other hand however, shortgrain pre-cut
sheets are preferably used for flip-top boxes, as they
clearly favour the stability of the lid (no crooked
closures, no easy tearing-off of the lid), the rigidity of
the pack as a result of a higher stability in the
transverse direction and the flat position of the pack,
i.e. as small a curvature of the pack as possible, compared
with the use of longgrain materials.
By using scoring lines instead of grooves, the elastic
restoring forces are surprisingly clearly reduced with the
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result that shortgrain materials can be used problem-free
and swiftly to produce the boxes without problems arising
with the gluing of the box because of the smaller available
surface.
To produce scoring lines, the thickness of the material
forming the pack is reduced using a scoring knife. For this
purpose, the pre-cut sheet is placed on a flat support and
worked with a scoring knife with the result that, in
addition to a compression, material can also be removed.
Depending on the shape of the scoring knife, for example a
v- or u-shaped cross-section is formed. As the support does
not have channels at points opposite the scoring knife, as
with the process for producing grooves, but rather a flat
surface, a reduction in thickness results and not, as with
the grooves, a deformation without a reduction in
thickness.
The extent of the reduction in thickness depends on the
material used and on the fold area affected. Scoring lines
of vertical fold areas are formed by a 10-80%, preferably
30-70%, quite particularly preferably 40-60% and for
example approx. 50% reduction in the thickness of the paper
or cardboard, scoring lines of horizontal fold areas by a
10-50%, preferably 20-40% and for example approx. 30%
reduction in the thickness of the paper or cardboard.
Scoring lines are also preferred for a second reason for
the pre-cut sheets according to the invention. They have
the advantage that, when they are located on the inside of
the finished pack, the outside appears fully intact and
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unworked and therefore offers the consumer a better optical
appearance, which is not possible when grooves are used.
The extent and the type of rounding can be fixed by the
number of fold lines and their distance from one another. 6
to 8, in particular 7, fold lines per fold area which are
located at a distance of approx. 1 mm from one another are
preferred. Upon folding, a box with round edges results;
the radius of the rounding then approximately corresponds
to that of a cigarette customary in the trade. 2 fold lines
per fold area which are located at a distance of 6 to 8 mm,
in particular approximately 7 mm, from each other are also
preferred. Upon folding a box with chamfered (or bevelled)
edges then results.
For a uniform optical appearance of the box it is further
preferred that all fold areas have the same number of fold
lines.
For the meeting of the vertical and horizontal fold areas
it is preferred that the end of the circle arc segment and
the end of the S-curve run at right angles from each other
and lie parallel to the edges of the main surface fields as
in this way a problem-free transition between the different
fold areas is possible.
The circle arc segment and the S-curve are preferably not
connected to each other, or connected only at the corner
point of the main surface fields. Although it is also
possible in principle for there to be an at least partial
connection between circle arc segment and S-curve, upon
folding-up to form the box, creasings and irregularities
CA 02437936 2003-08-12
then occur in the transition area between the two different
fold areas.
It is furthermore preferred that at least one fold area is
5 delimited either by a circle arc segment or an S-curve,
just as it is preferred that in all fold areas which meet
at their two ends essentially at a right angle to other
fold areas, both ends of these fold areas are delimited
either by the circle arc segment or the S-curve. Finally it
10 is also preferred that all fold areas lying parallel to
each other are in each case delimited either by a circle
arc segment or an S-curve. In all three cases this leads to
a better optical impression.
The pre-cut sheets are produced in known manner, i.e. the
pre-cut sheets are taken off from widths of pre-cut sheet
material which are stored on rolls and printed, preferably
as shortgrain pre-cut sheets. This is usually followed by a
step in which the pre-cut sheets are worked by a scoring
knife or grooving unit in the described manner and at the
same time punched and/or cut and optionally embossed. By
customary folding and gluing at the side surfaces, the
finished for example cigarette box is then obtained by
machine, which usually contains a cigarette group wrapped
in an inner liner. A customary collar part is normally also
inserted into hinge-lid boxes according to the invention,
which, in the opened box, protrudes slightly from the
inside of the box front wall and has a recess which makes
it possible to grasp the cigarettes located in the box.
The invention will be explained in the following using an
embodiment. There are shown in:
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Figure 1 a pre-cut sheet according to the invention for
the production of a hinge-lid cigarette box and
Figure 2 a view of detail Y of Fig. 1.
A first main surface field 20 is to be seen which
corresponds in the finished box to the front wall of the
box part of the box, with its adjacent side-surface fields
22 and 24. A first and second vertical fold area 90 and 91,
which are formed here by 7 scoring lines 100 and which have
a quadrant on their top end, are located between the left-
hand first side-surface field 22 and the first main surface
field 20 and also the first main surface field 20 and the
right-hand first side-surface field 24.
The base field 30, followed by the second main surface
field 40, joins above with the first main surface field 20.
The first horizontal fold area 80 is located between the
first main surface field 20 and the base field 30, the
second horizontal fold area 82 between the base field 30
and the second main surface field 40. These two horizontal
fold areas 80 and 82 are also formed by 7 scoring lines 100
each of which displays an S-shaped line at both its ends.
The second main surface field 40 which corresponds in the
finished box to the back of the box part is flanked by the
left-hand second side-surface field 42 with the left-hand
side-surface field end tab 46 located thereon and the
right-hand second side-surface field 44 with the right-hand
second side-surface field end tab 48 located thereon. A
third and fourth vertical fold area 92 and 93 lie in
between.
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The third main surface field 50, to which the lid rear wall
corresponds in the finished box, joins up with the second
main surface field 40. The main surface fields 40 and 50
are separated by the fold line 12 about which the lid in
the finished box can be swivelled. The fifth vertical fold
area 94 and the sixth vertical fold area 95 are located
between the third main surface field 50 and the left-hand
third side-surface field 52 with the left-hand third side-
surface field end tab 56 located thereon on one side and
the right-hand third side-surface field 54 with the right-
hand third side-surface field end tab 58 located thereon on
the other side. The vertical fold areas 92 and 93 and also
94 and 95 are separated from each other by indents which
can extend up to the fold line 12 or even further.
The lid field 60 follows on from the top side of the third
main surface field 50 which is followed for its part by the
fourth main surface field 70. The third horizontal fold
area 84 is located between the third main surface field 50
and lid field 60 and the fourth horizontal fold area 86
between lid field 60 and the third main surface field 70,
these again, like all the other fold areas, being formed by
7 scoring lines.
The left-hand fourth side-surface field 72, the right-hand
fourth side-surface field 74 with the seventh and eighth
vertical fold areas 96 and 97 located in between and also
the strengthening field 72 group around the fourth main
surface field 70. This strengthening field 72 had only four
scoring lines 100 on account of its somewhat smaller
dimensions.
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The vertical and horizontal fold areas meet at the corners
of the main surface fields, thus e.g. the vertical fold
areas 90 and 91 meet the horizontal fold area 80 at the top
corners 21 and 23 of the main surface field. The vertical
fold areas end in the version of Figure 1 in a quarter arc
which passes smoothly on one side into the top edge of the
respective neighbouring side-surface field and smoothly on
the other side into the outer edge of the respective main
surface field. The horizontal fold areas end in S-curves
which pass smoothly into the outer edges on one side of the
respective neighbouring main surface field and on the other
side of the neighbouring base field or top side field.
In addition to the scoring lines 100 of the various fold
areas, further fold lines are to be seen, thus the fold
line 12 between the second 40 and the third 50 main surface
field, the fold lines 77 in the strengthening field 72, and
the fold lines 55 and 45 about which the side-surface field
end tabs can be swivelled.
To produce the cigarette box, firstly the side-surface
fields 42 and 44 can be folded upwards by 90° and the side-
surface field end tabs 46 and 48 located thereon then
folded inwards, likewise by 90°. The bottom part of the
pre-cut sheet 10 is then folded upwards by 90° with the
base field 30 and the first main surface field 20, as a
result of which the side-surface field end tabs 46 and 48
come into contact with the base field 30 and are glued. If
the first main surface field 20 is folded further (by 90°),
the side-surface fields 22, 42 and 24, 44 come to lie on
top of one another and can be glued, with the result that
the bottom part of the box, the box part, is finished. The
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top part, the lid part, of the box is produced in similar
manner, i.e. the side-surface field end tabs 56 and 58 are
glued to the top side field 60. The strengthening field 72
is glued inwardly onto the fourth main surface field 70 and
thereupon the side-surface fields 52, 72 and 54, 74 glued
together. The scoring lines 100 are therefore located on
the inside of the finished box and are not visible to the
consumer from the outside.
The hinge-lid box obtained by the folding described has
rounded-off longitudinal edges. The four horizontal main
edges are also rounded off. As a result of the meeting of
circle arc segment and S-curve at the ends of the fold
areas, a smooth transition between the fold areas results
and all 8 corners of the box are rounded off in this way.
The meeting of circle arc segment and S-curve is
represented enlarged in the detail view of Figure 2. Each
of the vertical fold areas 91 and 93 ends in a circle arc
segment of approx. 60 to 70°, the horizontal fold areas 80
and 82 in an S-curve. Circle arc segments and S-curve lie
adjacent to one another without being connected to one
another and meet at the corner points 23 and 43.
