Container of corrugated sheet material for foodstuff, in particular cakes

Abstract: There is disclosed a container of corrugated sheet material for foodstuffs, in particular cakes and similar confectionery products of big sizes, comprising a bottom wall (2) and a side wall (3) integral with each other and adapted to form a cavity (4), the side wall (3) having an outwardly-overturned border band (6) at the opening contour of the cavity (4).

Description: 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. 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. The preamble of claims 1 and 9 is based on this prior art. 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. It is also known from document US 5775577 a disposable insulated container with microflute structure. In particular the container is adapted to contain hot liquids and comprises a corrugated sheet material which extends substantially circumferentially around the side wall of the inner container and which is covered by a second outer sheet laminate of thin flexible paper material presenting substantially smooth outer surface for engagement by the hand of a user of the container. The container according to US patent has a bottom wall and a side wall manufactured separately of said bottom wall; said side and bottom walls are made integral with each other and form a cavity having an opening facing upwardly in the normal use condition of the container itself. At the contour of said opening, the side wall has a border band overturned outwardly of said cavity and delimited by an annular fold of the sheet material defining said opening contour of the cavity. It is also known from document US 5839653 a container for holding hot beverages having an insulating wall of corrugated paper. The container comprises a bottom wall and a side wall manufactured separately of said bottom wall; the side and bottom walls are made integral with each other and are adapted to form a cavity having an opening facing upwardly in the normal use condition of the container itself; at the contour of the opening, the side wall has a border band overturned outwardly of said cavity and delimited by an annular fold of the sheet material defining said opening contour of the cavity. While the containers of known type briefly described above are widely spread, they however have some drawbacks and operating limits. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. With reference to the drawings, the container in accordance with the invention is generally identified by reference numeral 1. 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. 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). 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. 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. 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. 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. 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. 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. 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. 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. 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 α 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. 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. 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. 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. 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. 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. 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. The invention achieves important advantages. 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. 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. 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.

Claims: A container of corrugated sheet material for baking 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 end 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, said corrugated sheet material being paper material adapted to enable food holding and baking, 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), said corrugated sheet (10) defining the outer surface of said cavity (4), said outer surface being 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°. A container as claimed in claim 1, characterized in that said corrugations (8) have a major extension direction oriented with an inclination to the bottom wall (2) of an angle (α) smaller 10-15° and preferably oriented substantially parallel to said bottom wall (2) and to said annular fold (7) delimiting the border band (6). 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). 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. 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). 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). 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). A container as claimed in claim 7, 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). A process for manufacturing containers for baking foodstuffs, in particular cakes and similar confectionery products, of the type according to claim 1 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 the corrugated sheet defines the outer surface of the cavity, the corrugations (8) have a major extension direction oriented with an inclination to the bottom wall (2) of an angle (α) smaller than 45°, and by a further 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). A process as claimed in claim 9, 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).

Inventors: ANGHILERI GIANMARIO, ANGHILERI, GIANMARIO
Applicants: NOVACART SPA
Application year: 2000
Main classification: B65D3
IPC codes: B65D3, B65D85