[0001] The present invention relates to a container of corrugated sheet material for foodstuffs,
in particular cakes and similar confectionery products, of the type comprising a bottom
wall and a side wall manufactured separately of said bottom wall, wherein said side
and bottom walls are made integral with each other and adapted to form a cavity having
an opening facing upwardly in the normal use condition of the container itself.
[0002] It is known that containers of corrugated paper material for foodstuffs, in particular
confectionery products of great sizes such as cakes, panettones and the like, are
usually made of two parts, ie. a bottom wall and a side wall integral with each other
at their edge regions where they are glued together. These walls form a cavity having
an opening facing upwardly in the normal use condition of the container itself, which
is adapted to house the dough during the baking step, and the finished product when
baking is over.
[0003] In particular, the side wall is defined by a single portion of corrugated paper material,
suitably shaped and closed to form a ring by overlapping and gluing of the end flaps
in order to obtain a truncated-cone conformation, so that the container slightly flares
to promote its superposition on other containers thereby forming stacked packs of
reduced bulkiness.
[0004] While the containers of known type briefly described above are widely spread, they
however have some drawbacks and operating limits.
[0005] In fact, first of all, they tend to become irregularly deformed during cooking due
to stresses to which they are submitted by the dough housed therein which has a tendency
to expand and exert an important pressure against the inner face of the side wall.
Said wall does not possess an even mechanical strength along all its annular extension
because, at the overlapping region between the end flaps glued together, a section
of greater stiffness is created that, by contrast, tends to cause deformation of the
regions adjacent thereto, with a decrease in their bending.
[0006] Practically, said region of greater stiffness, under the action of the swelling dough,
moves outwardly above all close to the opening contour of the container cavity far
away from the bottom wall that exerts its stiffening action on the side wall only
close to the band strictly in its proximity. The confectionery product therefore does
not take an even shape but, when cooking is over, close to the overlapped end flaps
of the container side wall it exhibits a bulging or swollen region with respect to
the theoretical contour line that said container should impart to it.
[0007] In addition, in the known art, the upper edge of the container is a sharp edge that
may sometimes cut or penetrate and is therefore dangerous during handling of the container
itself.
[0008] Finally, if the paper material consists of coupling of two or more layers, partial
separations between these layers may occur, and therefore frayed regions may appear
at the upper edge of the container where emerging of the cutting and trimming lines
of the different layers may cause the latter to open out.
[0009] Under this situation the technical task underlying the present invention is to devise
a container of corrugated paper material for foodstuffs capable of substantially obviating
the mentioned drawbacks.
[0010] Within the scope of this technical task it is an important aim of the invention to
devise a container of corrugated paper material capable of keeping its original shape
unchanged, by efficiently counteracting the expansion stresses developing during baking
of the dough housed therein.
[0011] Another important aim of the invention is to devise a container of corrugated paper
material provided with a rounded edge, which is not therefore sharp at its opening.
[0012] A further aim of the invention is to devise a container of corrugated paper material
that, where formed of two or more layers, is not subject to possible fraying at the
edge of its opening, as a result of separation between the layers themselves.
[0013] A still further aim of the invention is to provide a container the shape of which
is adapted to enable folding and bending actions thereon, as well as greater resistance
to deformations.
[0014] A further important aim of the invention is to make the upper edge of the food container
stronger by providing it with greater structural stiffness and reducing the risks
of breaking of its side wall due to tearing.
[0015] The technical task mentioned and the aims specified are substantially achieved by
a container of paper material for foodstuffs, in particular cakes and similar confectionery
products, which is characterized in that said side wall at the opening contour has
a border band overturned preferably outwardly of said cavity and delimited by an annular
fold of the sheet material defining said contour of the cavity opening.
[0016] Description of a preferred but not exclusive embodiment of a container of corrugated
paper material for foodstuffs in accordance with the invention is given hereinafter
by way of non-limiting example, with reference to the accompanying drawings, in which:
- Fig. 1 is a perspective view of the container in accordance with the invention;
- Fig. 2 is a partial cross-sectional view in a vertical plane and to an enlarged scale
of the container shown in Fig. 1;
- Fig. 3 is an enlarged detail of the container in Fig. 1; and
- Fig. 4 is a plan view of a side wall before bending and subsequent engagement with
the bottom wall.
[0017] With reference to the drawings, the container in accordance with the invention is
generally identified by reference numeral 1.
[0018] It comprises a bottom wall 2 and a side wall 3 separated from each other and each
defined by a shaped portion of corrugated sheet material, said walls being made mutually
integral by gluing at a peripheral region 2a of the former and a bent edge region
3a of the latter.
[0019] In particular, during the container production step a first portion intended to define
the bottom wall 2 is provided to be cut from a substantially flat support of corrugated
paper material (as shown in Fig. 4, for example).
[0020] For instance, a first and widespread typology of paper containers for confectionery
products involves use of a bottom wall of circular shape, as shown in Fig. 1. At all
events, depending on requirements, different container shapes adapted to the type
of cake to be prepared may be provided.
[0021] Also cut for each container is a second flat portion which is separated from the
preceding one and will be used to constitute the container side wall 3. This second
portion will preferably consist of a strip of sheet material to be suitably bent so
that its edge region 3a will be ready for gluing to the peripheral region 2a of the
bottom wall 2; this portion will then be closed to form a ring around the bottom wall.
[0022] It should be noted that the container consists of at least two separate portions
(a base and a side wall). This enables a side wall 3 made up of the desired amount
of material to be obtained. In other words, when the container has been completed
the side wall 3 will not have material in excess, swellings, folds or corrugations
in addition to those already present in the strip designed to define it and the container
thus obtained will therefore be much stiffer and stronger than the paper containers
made through subsequent bendings starting from a single sheet. Still for the purpose
of avoiding possible swellings, folds or corrugations, the bent edge region 3a will
be defined by a plurality of tabs 11 separated by a cut 12. During the engagement
step with the bottom, these tabs 11 partly overlap one another thereby avoiding deformations
due to excess material at this region.
[0023] As can be also viewed from Fig. 4, a weakening line 13 intended to facilitate bending
of the side wall 3 is also present; therefore the side wall 3 in an assembled condition
will have a portion 3a parallel to bottom 2 and a portion substantially perpendicular
to the latter or at most slightly flared outwardly of cavity 4.
[0024] Also identified in Fig. 4 is an ideal folding line 14 around which the upper edge
of the side wall 3 will be overturned. This overturning operation can take place by
overturning of the border band 6 either when the side wall 2 is in a flat condition
(Fig. 4), or before assembling with the bottom wall 2 and also possibly simultaneously
with dampening of the folding region; alternatively folding will follow assembling
after dampening of the region itself.
[0025] As shown in the figures, the side wall 3 is closed to form a ring by overlapping
and gluing of the end flaps 3b that therefore will constitute a section of greater
stiffness than all the remaining part of the side wall 3 itself.
[0026] Practically, the side wall 3 and bottom wall 2 form a cavity 4 having an opening
facing upwardly in the normal use condition of the container.
[0027] In an original manner, the side wall 3 at the contour of opening 5 has a border band
6 overturned outwardly of cavity 4 and delimited by an annular fold 7 of the paper
material defining said contour of opening 5.
[0028] Advantageously, the paper material of the side wall 3 comprises at least one face
crossed by corrugations 8 having a major extension direction which is not oriented
vertically as in common containers. In particular corrugations 8 have an inclination
to the horizontal (or bottom plane 3) of an angle a not greater than ± 45°, more preferably
this inclination will be in a range included between ± 10° and ± 15° and most preferably
the major extension direction will be oriented substantially parallel to the bottom
wall 2 and therefore also to the annular fold 7 delimiting the border band 6. The
annular fold 7 is practically executed mainly at the grooves of corrugations 8 disposed
at the contour of opening 5 so that achievement of said annular fold is facilitated
due to the greater flexibility offered by the paper material at said grooves.
[0029] In order to obtain extension in the desired direction, the strip that will define
the side wall will be suitably cut from the corrugated material so as to follow the
rib course.
[0030] Obviously, should the container have a slightly flared side wall 3, the corrugation
extension in the finished product will be slightly inclined and this deviation from
the horizontal will be more apparent at the region where the strip edges are jointed
together on the side wall because at this point the two inclinations are in opposition
to each other.
[0031] At all events, in these containers too the overall corrugation course will be substantially
horizontal so as to promote the folding operations at the border band 6.
[0032] It will-be recognized that orientation of the paper material corrugations in a direction
substantially parallel to the bottom wall not only efficiently counteracts the tendential
increase in the container flaring due to expansion of the dough during baking (because
it brings to formation of a plurality of stiff annular ribs), but it also enables
breaking of the paper material to be avoided, which on the contrary would occur if
said corrugations were disposed transversely of the bottom wall, i.e. in a substantially
vertical direction in the normal use condition of the container. In fact, in the last-mentioned
case, the annular fold 7 would cross the corrugation ridges at right angles where
the material elasticity is obviously to a minimum degree and therefore cracking and
tearing formations are very likely to occur.
[0033] From a manufacturing point of view it is to be noted that preferably the corrugated
paper material consists of a smooth sheet 9 adapted to come into direct contact with
the foodstuff and facing the inside of cavity 4, and a corrugated sheet 10 that obviously
will define the outer surface of the container. In this way the annular fold 7 forms
a rounded edge covered with the smooth sheet 9. Clearly, both sheets 9, 10 are adapted
to withstand the baking temperatures required for the different types of foods.
[0034] As it is also shown in Fig. 2, the border band 6 has an extension surface disposed
parallel to the side wall 3, so that penetration of the border corrugations into the
grooves present in the side wall 3 and due to the corrugations themselves is possible
at least partly.
[0035] The invention achieves important advantages.
[0036] First of all the border band 6 and annular fold 7 delimiting it constitute a perimetric
collar greatly stiffening the upper part of the side wall 3 and reducing to a minimum
the structural discontinuity effect caused by the presence, along the annular extension
of the side wall itself, of the region of greater thickness wherein the end flaps
3b overlap one another and come into engagement. The container in accordance with
the invention therefore does not tend to become deformed during baking of the foodstuff
contained therein and said foodstuff, when cooking is over, is shaped evenly without
protuberances or irregular swellings.
[0037] In addition, the opening contour of the container is formed of the annular fold of
the paper material and is therefore of rounded conformation, without sharp edges.
[0038] Finally, should the paper material be formed of two or more sheets coupled to each
other, the cutting and trimming lines of said sheets are disposed at the end of the
border portion folded back outwardly and downwardly and not at the opening contour
of the container; possible partial separations or fraying between the sheets therefore
would stop at the annular fold delimiting said border portion and could not go on
in the cavity of the container itself.
1. A container of corrugated sheet material for foodstuffs, in particular cakes and similar
confectionery products, of the type comprising a bottom wall (2) and a side wall (3)
manufactured separately of said bottom wall (2), said side and bottom walls (2 and
3) being made integral with each other and adapted to form a cavity (4) having an
opening (5) facing upwardly in the normal use condition of the container itself, characterized
in that said side wall (3) at the contour of said opening (5) has a border band (6)
overturned preferably outwardly of said cavity (4) and delimited by an annular fold
(7) of the sheet material defining said opening contour of the cavity (4).
2. A container as claimed in claim 1, characterized in that said corrugated sheet material
on said side wall (3) comprises at least one face crossed by corrugations (8) having
a major extension direction oriented with an inclination to the bottom wall (2) of
an angle (α) smaller than ± 45°, preferably not exceeding ± 10-15° and more preferably
oriented substantially parallel to said bottom wall (2) and to said annular fold (7)
delimiting the border band (6).
3. A container as claimed in claim 2, characterized in that said annular fold (7) delimiting
said border band (6) mainly extends at the corrugation (8) grooves of the sheet material
disposed at said contour of the cavity opening (5).
4. A container as claimed in claim 1, characterized in that said corrugated sheet material
is formed by coupling of at least one smooth sheet (9) and one corrugated sheet (10),
preferably arranged to withstand baking temperatures.
5. A container as claimed in claim 4, characterized in that said corrugated sheet (10)
defines the outer surface of said cavity (4) and in that said annular fold (7) forms
a rounded edge covered with said smooth sheet (9).
6. A container as claimed in claim 1, characterized in that said border band (6) has
an extension surface disposed parallel to said side wall (3).
7. A container as claimed in claim 1, characterized in that said corrugated sheet material
is paper material adapted to enable food holding and baking.
8. A container as claimed in claim 1, characterized in that the side wall (3) has a bent
edge region (3a) linked, preferably glued, to a periphery (2a) of the bottom wall
(2).
9. A container as claimed in claim 8, characterized in that said bent edge region (3a)
has a predetermined number of tabs (11) separated from each other by cuts (12) and
arranged to at least partly overlap one another under assembling conditions of the
side wall (3) with the bottom wall (2) .
10. A process for manufacturing containers for foodstuffs, in particular cakes and similar
confectionery products, comprising the following steps:
- setting a corrugated sheet material of a substantially flat extension,
- cutting a first portion from said material so as to define a bottom wall (2) of
the container,
- cutting a second portion from said material so as to define a side wall (3) of the
container separated from said bottom wall (2),
- mutually and integrally associating the bottom wall (2) and side wall (3) so as
to form a cavity (4) having an opening (5) turned upwardly in the normal use condition
of the container itself, characterized in that it further comprises a step of folding
a border band (6) preferably outwardly of said cavity (4), the border band (6) being
delimited by an annular fold (7) of the sheet material defining said opening contour
of the cavity (4).
11. A process as claimed in claim 10, characterized in that said step of folding the border
band takes place either before the step of associating the bottom wall (2) with the
side wall (3) or after the association step upon dampening of this border band (6).