WO2007029272A1

WO2007029272A1 - Bag for collecting organic waste or foodstuffs

Info

Publication number: WO2007029272A1
Application number: PCT/IT2005/000510
Authority: WO
Inventors: Damiano Chinello
Original assignee: Aspic S.R.L.
Priority date: 2005-09-07
Filing date: 2005-09-07
Publication date: 2007-03-15
Also published as: EP1931572B1; PL1931572T3; EP1931572A1; ES2618327T3; SI1931572T1

Abstract

The present invention concerns a bag (1) for collecting waste or fresh foodstuffs with a bottom flap (3) inside it which can be folded down from a non operative position, in which the bottom flap is substantially situated vertically, into an operative position, in which the bottom flap is substantially situated horizontally, parallel to the lower base (4) of the bag (1), to increase its resistance.

Description

"BAG FOR COLLECTING ORGANIC WASTE OR FOODSTUFFS"

FIELD OF THE INVENTION

The present invention concerns α bag for collecting organic waste or foodstuffs, in particular it concerns a highly biodegradable bag for collecting compostable waste. BACKGROUND OF THE INVENTION

In many Countries the regulations on collection and disposal of waste provides the organic portion to be isolated in order to be subjected to further disposal processes that reduce their impact on the environment or make it possible recycling it or usage in different technical fields. For example the organic fracYion of urban waste collected separately or organic residue from farming and industrial activities are subjected to a so-called "composting" process. Composting may be defined as the process through which the natural decomposition, to which any organic substance is subject by the effect of the microbic flora normally present in the environment, is controlled, accelerated and optimised. In other words composting is an aerobic process of biological decomposition of organic substances which takes place in controlled conditions and allows a biologically stable product called "compost" to be obtained. The compost obtained from separately collected (or preselected) urban organic waste contains an amount of humus, microbic flora and fertilising elements such as to allow its use for agronomic uses, for example as fertilizer in plant nurseries and for crops in general. Compost may also be obtained from waste that is not separately collected (not preselected), suitably treated, to be used in sectors other than agriculture, for example as filling material for environmental recovery, or for the daily covering of landfill sites. In order to obtain a high quality compost [stable and having high fertilising characteristics), it is necessary for the bag or bag used for collecting the organic waste to be biodegradable too, and to favour the natural process of decomposition of the waste. Among the containers traditionally used for waste collection are bags made of plastic polymers. One of the materials most used for the purpose is polyethylene. Disadvantageously, though resistant, plastic bags are not biodegradable and their disposal is difficult and expensive. In other words, bags of this type are highly polluting for the environment. Moreover, bags made of plastic material are not transpiring, that is they are not permeable to air, and so they hinder the circulation of oxygen towards the waste that they contain, which tends to rot rapidly with the consequent formation of unpleasant smells. For these reasons, plastic bags are not suitable for the collection of compostable organic waste.

In the field of the separate collection of compostable organic waste, bags and bags obtained from biodegradable raw materials, for example from corn starch, have recently provided on the market. Traditional containers of this type are widely used in the home for the collection of organic waste, for example kitchen scraps, leaves or other vegetal material, etc. Like compostable waste, com starch is subject to natural decomposition and so it does not pollute the environment. Disadvantageously, the permeability of this type of bags/bags to air is low. For this reason the amount of air which, in conditions of normal bag use, interacts with the waste that it contains is minimum and the waste is often subject to rapid decomposition (rotting) which produces unpleasant smells. This inconvenient aspect has important implications also for the quality of the compost obtained from the collected waste. In fact, too rapid a decomposition of the waste in the bag can have a negative influence on the phases of the composting process after the collection of the waste, and it may lead to the formation of a poor quality compost. Another problem associated with the production and use of this type of bags and bags lies in the fact that the corn starch polymer (or the biodegradable material used alternatively) is usually hot-extruded with synthetic polymers which increase its mechanical characteristics but which are not biodegradable. In fact, normally corn starch polymer, as such (that is considered individually), does not allow containers or bags to be made that are sufficiently resistant for use in the collection of organic waste, which may even have quite a high specific weight. So the starch is usually bonded with plastic polymers having suitable mechanical properties, for example polyethylene, which are not subject to natural decomposition and which, once released in the environment, are configured as polluting substances. Moreover, corn starch is degradable in contact with the liquids released by organic waste and, therefore, the traditional bags made with this material may be subject to breakage if the waste contains considerable water quantities (for example, consider fruit). For some time the need has been felt to have organic waste containers that are completely biodegradable, highly transpiring and, at the same time, resistant. A further type of containers traditionally used for the collection of organic waste is bags/bags made of paper, for example of the type obtained from a blank suitably folded and glued. The bags/bags made of paper material are usually available in folded configuration, that is they are sold flattened, and the user opens the bag or bag into an erect configuration to use it. Advantageously the bags and bags made of paper material, for example paper or cardboard, have a considerable transpiring capacity and favour the passage of air towards the waste that they contain in considerably greater quantities than in bags made of plastic, or with com starch-based polymers. This characteristic allows the triggering of a gradual process of oxidation of the waste and therefore favours the controlled decomposition of the waste without it jotting in a short time. For these reasons the final compost obtained when collecting the waste in paper bags is of high quality. Moreover the high permeability to air of paper bags minimises the formation of unpleasant smells, a phenomenon which is easily encountered in the use of containers made of plastic or corn starch- based polymers. A not negligible problem presented by paper bags is their poor mechanical strength in the presence of liquids. In fact the liquids released by the waste collected in these bags are rapidly absorbed by the paper material, which weakens and tends to collapse. In these cases it is difficult to maintain the integrity of the bags during handling. Paper bags are generally made from blanks suitably folded and glued. The liquids released by the waste contained in a paper bag often act as solvents for the glue, that is they weaken the point where the bag is glued, which may fail, with consequent breakage of the bag. Paper bags or bags are often used as shoppers, that is for carrying fresh food from supermarkets and food shops. Disadvantageous^, bags made of paper, cardboard or similar paper material, do not guarantee holding if the food they contain has a heavy weight. The aim of the present invention is to provide a container in the form of a bag or bag for collecting organic waste, in particular for collecting compostable organic waste, or for holding foodstuffs, which simply and effectively overcomes the drawbacks of the traditional bags/bags, being at the same time cheap and easy to use. A further aim of the present invention is to provide a bag for collecting organic waste, in particular for collecting compostable organic waste, or for holding foodstuffs, which is biodegradable, resistant and highly permeable to air.

A further aim of the present invention is to provide a bag for collecting compostable organic waste, in particular for the selective collection of said waste, which favours the correct activation of the respective composting process.

Yet another aim of the present invention is to provide a bag for the selective collection of compostable organic waste which is resistant to the liquids released by the same waste.

Another aim of the present invention is to provide a bag for the selective collection of compostable organic waste which minimises the formation of unpleasant smells due to the decomposition process of the waste that it contains. SUMMARY OF THE INVENTION

These and other aims are achieved by the present invention which concerns a bag for collecting waste or holding foodstuffs according to claim 1. The term "bottom flap" is used to identify any element having a shape suitable to overlap at least in part the lower base, or bottom, of the bag. Preferably the bottom flap has a flat shape, for example it may be a suitably shaped sheet.

Advantageously the bag according to the present invention is provided on the inside with a bottom flap that may be turned from a non operative position, in which the bottom flap is substantially vertical and parallel to the side walls of the bag in an erect configuration (bag open), to be brought into an operative position, in which the bottom flap is substantially laid horizontal, parallel to the lower base of the bag, so as to increase its resistance. The bottom flap may be folded down by the user into operative position in such a way that it at least partly overlaps the lower base of the bag itself, forming a kind of double bottom for the bag. In this way it is possible to increase the resistance of the base (bottom) of the bag and of the bag in general. In other words, thanks to the presence of the bottom flap on the base of the bag it is possible to increase the weight of the content with respect to that normally contemplated for traditional bags/bags. The bottom flap may be simply inserted inside the bag, for example during its production, or it may be positioned on the inside of the bag and anchored to the same to prevent it coming out or to prevent undesired movements inside the bag. Preferably the bottom flap is inserted in the bag and is anchored to the same by means of one or more spots of glue on a side wall. The fixture is of a removable type, that is it must be possible to separate the bottom flap easily from the inside surface of the bag in order to fold it down onto the bottom. The bag according to the present invention is made of paper or cardboard. Preferably the bag is made of recycled paper, having for example a weight of 80g/m². The bag is made of a material that is at least partly transpiring, that is at least partly permeable to air, so as to favour the aeration of the waste collected in the bag or the aeration of the foodstuffs carried in it. Paper and cardboard may be suitable materials for the purpose. Permeability to air allows the activation of the oxidation processes necessary for the waste composting process and contributes to slowing down the natural fermentation/ripening of fresh foodstuffs. Preferably the bag itself is biodegradable, that is the paper or cardboard with which the bag is made is highly biodegradable. The bag material may be chosen in such a way as to be compostable in a normal composting cycle of collected waste. In other words the bag material is preferable compostable in a time corresponding to the definitive decomposition of the organic waste that it contains. Since the bag is at least partly transpiring, any waste that it contains is not subject to rapid rotting as is found when using bags made of com starch or plastic bags. On the contrary the aeration of the waste activates slower oxidation and decomposition processes than those provided by the above-mentioned traditional bags. Consequently the bag according to the present invention makes it possible to minimise the formation of unpleasant smells.

The bottom flap may be made of different materials depending on the final use of the bag.

If the bag is to used as a shopper for carrying fresh foodstuffs, the bottom flap may be made of cardboard, having for example a thickness of 0.5 mm, that is sufficiently thick to bear heavy foods in cooperation with the lower base of the bag.

If the bag is intended for collecting waste, especially compostable organic waste (typically collected separately from other waste at home), the bottom flap is made of an absorbent material. For example the bottom flap is made of paper or card having a weight between 150 and 180 g/m². Alternatively the bottom flap may be made of a spongy material. This characteristic is particularly advantageous, since this type of waste usually releases liquids which would wet the surfaces of the bag, weakening the same. In particular the function of the bottom flap is to prevent, or at least limit, the contact between the liquids released by the waste and the adhesive substance usually used to glue together the blanks with which paper bags are usually made. Thanks to the absorbent capacity of the bottom flap, the lower surfaces of the bag and the gluing points on the lower base of the bag, that is the spots of glue used to form the bottom of the bag from a blank, are protected against the dissolving effect of the liquids. In comparison with traditional paper bags/bags, the resistance to liquids is maximised. Preferably the bottom flap, as well as being absorbent, is also biodegradable, more preferably compostable. This means that the whole bag may be completely biodegradable. The formation of unpleasant smells is further limited by the fact that the liquids released by the waste are at least partly absorbed by the bottom flap. The bag according to the present invention may be applied in various sectors related to the collection of food and/or waste. The bag may therefore be realised with variable dimensions, that is with capacities suited to the different uses, for example with capacities between 8 litres and 120 litres. Moreover the bag may have bottoms of a different type, that is the lower base of the bag may have different configurations depending on the final use for which the bag is intended. For example the bag may have a "flat" bottom, a "square" bottom or a "crossed" bottom. The bag according to the present invention boasts a series of advantages with respect to traditional bags/bags. In fact if allows a greater supply of air to the material that it contains in comparison with that supplied by plastic or com starch bags, with evident advantages as regards the reduction of unpleasant smells. Moreover the bag according to the present invention has greater resistance than traditional paper bags, both as regards the weight of the material contained in the bag and the presence of liquids. These characteristics allow the bag according to the invention to be used efficaciously for holding foodstuffs and, above all, for collecting organic waste. In particular, since the bag and the bottom flap inside it may be made of compostable material, the bag is suitable for the selective collection of urban organic waste, such as is collected in the home, in restaurants, in markets, etc.

The bag according to the present invention allows high quality compost to be obtained. It is a known fact that the best compost is obtained from vegetal organic waste, which decomposes rapidly, giving origin to a humus rich in fertilising elements. The bag according to the invention is made of paper material, so it is rich in vegetal fibres. In particular the paper or cardboard is rich in lignin. The presence of these vegetal fibres, and particularly of lignin, allows the optimisation of the quality of the compost that can be obtained using the bag. BRIEF DESCRIPTION OF THE DRAWINGS

Further aspects and advantages of the present invention will be made clearer by the following description, provided as an illustrative but not limiting example, with reference to the enclosed schematic drawings in which: figure 1 is a perspective view of a bag according to the present invention in a first configuration; figure 1 A is a side view of the bag shown in figure 1 ; - figure I B is a perspective view of a bag according to the present invention in a second configuration; figure 2 is a plan view of a first blank for the production of a bag according to the present invention; figure 3 is a plan view of a second blank for the production of a bag according to the present invention; figure 4 is a plan view of a third blank for the production of a bag according to the present invention; figure 5 is a plan view of a fourth blank for the production of a bag according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

With reference to figure 1 , α bag 1 according to the present invention is illustrated. The bag 1 has a capacity of about 8 litres and it is intended for the separate collection of compostable waste. The bag 1 is of the type with an open mouth and it is preformed from a blank (shown in figure 2). In general the bag 1 may have different capacities, that is it may be made with capacities of 10 litres, 50 litres, 100 litres, 120 litres, etc., depending on the different uses for which the bag, or bag, is intended. For example the bag 1 according to the present invention may be made with a capacity of 120 litres for collecting waste in supermarkets, in fresh food stores, in animal breeding establishments, in greenhouses, etc.

The bag 1 comprises a body 2, made up of a plurality of side walls A-F and of a lower base 4, and a bottom flap 3 housed inside it. The number, dimensions and arrangement of the side walls depend on the type of blank used for making the bag 1. Figure 2 illustrates a possible embodiment of a blank suitable for the purpose, in which the vertical creasing lines 5 identify the side walls A-F of the bag 1 . The bag 1 is therefore obtained from a suitably creased blank, folded and glued according to a technique known in the field of the production of bags and bags. The bag 1 is initially formed in a flattened configuration, that is it is folded, as shown in figure IA. The user can open the bag 1 , that is bring it into an erect configuration for use. The bag 1 shown in figure 1 is in an open or erect configuration, that is the bag has been substantially brought to its maximum dimensions by folding it along the vertical creasing lines 5 (or prefolding lines). The bag 1 is made of paper material, for example cardboard or paper suitable for foodstuffs. Preferably the bag 1 is made of recycled paper, with a low content of heavy metals, having a weight between 50 and 100 g/m². More preferably the bag 1 is made of recycled paper having a weight of about 80 g/m² and which is biodegradable in a composting cycle. This characteristic is particularly useful if the bag 1 is used for collecting compostable waste. In fact, in a single cycle composting of both the bag 1 and of the waste that it contains is obtained, with evident positive effects as regards the care of the environment. A normal composting cycle begins with the natural oxidation of the organic waste in the bag 1 and ends with the formation of the compost, a biologically stable product rich in humus, microbic flora and fertilising elements. The initial phase of the cycle fakes place during the collection of the waste by the user, while the subsequent phases and the final one are usually carried out in special sites run by the waste disposal companies in accordance with the national laws. In order to favour the exchange of air towards the content of the bag 1 , whether it is waste or fresh foodstuffs such as, for example, fruit and vegetables, the paper material chosen to make the bag 1 is at least partly permeable to air, that is at least in part transpiring. This characteristic allows the activation of the waste oxidation process or the activation of a minimum aeration of the foodstuffs, with evident advantages as regards their conservation. The bag 1 according to the present invention can therefore be advantageously used both for collecting waste and for holding foodstuffs. On the contrary, the traditional plastic (polyethylene) bags and those made of corn starch are not transpiring or they have low permeability to air, and consequently favour the rotting of the waste and the formation of unpleasant smells.

The presence of the bottom flap 3 allows the problems found in using traditional paper bags to be overcome. The bottom flap 3 is on element having a shape such as to overlap at least in part the lower base 4 of the bag 1 in order to increase its mechanical resistance and protect any gluing points of the blank 2 on the base 4. In figure 1 the blank 3 is a substantially flat element rectangular in shape. The bottom flap 3 is inserted in the folded, flattened bag 1. So the bottom flap 3 is initially situated in an intermediate position between the walls A and D of the bag 1 , parallel to them, as shown in figure 1 A. In general the bottom flap may be simply lnserfed in the bag 1 , without there being any particular ties to the body 2 of the bag, or it may be fastened to at least part of the internal surface of the bag 1. In figures 1 and IA it is possible to see that the bottom flap 3 partly overlaps the wall D. In particular in the shown embodiment the bottom flap 3 is attached in a non permanent way to the wall D of the bag 1 , specifically it is glued to the internal lower surface of this wall. In figure 2 the reference number 6 indicates the line along which the flap 3 is glued to the wall D. The bond thus obtained allows the bottom flap 3 to be secured in a stable position, avoiding it from moving about inside the bag ] or coming out of the bag. It is important for the bond between the bottom flap 3 and the inside surface of the bag to be easily detached by the user when preparing the bag 1 for use. In fact the bottom flap 3 has the characteristic that it can be folded down onto the bottom 4 of the bag 1 to assume an "operative" position substantially parallel to the bottom 4 of the open bag 1. In other words, once the user has opened the bag 1 , bringing it info the erect configuration shown in figure 1 , the bottom flap 3 may be easily turned in the direction indicated by the arrows R, breaking the gluing spots, to overlap the lower base (bottom) 4. For this reason the gluing of the bottom flap 3 must be such as to allow an easy separation of the surfaces without running the risk of damaging the bottom flap 3 or the bag 1.

It will be clear to the skilled in the field that the anchoring of the bottom flap 3 to the internal surface of the bag 1 may be realised in different ways, equivalent to gluing, for example by stitching or tongues.

Once it has been folded down onto the bottom 4 of the open bag 1 , the bottom flap 3 is configured as a double bottom for the same bag. Figure 1 B shows the bag 1 with the bottom flap 3 folded down to form a kind of double bottom. It is clear that the bottom flap 3 allows for increasing of the mechanical resistance of the bag 1 , avoiding the mentioned limits that paper bags/bags show as concerns the weight of the goods that they contain. So, in general, the bag 1 according to the present invention has the advantage of permitting to hold a heavier load than is possible with traditional paper bags/bags of the same type.

In general the bottom flap 3 may be made of different materials depending on the applications for which the bag is intended. For example, if the bag I is used as a shopping bag, the bottom flap 3 may be made of cardboard with a large thickness (1 or 2 mm) or of plastic. If the bag 1 is used for collecϊing coniposfable organic waste the bottom flap 3 is made of biodegradable material. In the example shown in figures 1-2 the bag 1 is used for collecting compostable organic waste, such as that collected separately in homes in the towns where the respective disposal service is provided. For this application the bottom flap 3 is made of a materia) which, as well as increasing the resistance of the lower base 4, is also absorbent. This characteristic is particularly advantageous because organic waste usually releases liquids which are easily absorbed by the bag 1 , with its consequent deterioration. The bottom flap 3 absorbs at least part of the liquids released by the waste, therefore minimising the absorption by the bag 1 with evident positive effects as concerns the resistance and duration of the same bag 1 . In other words, being in the operative position shown in figure 1 B (horizontal and at least partly overlapping the bottom 4), the bottom flap 3 has the dual function of cooperating with the lower base 4 to support the content of the bag 1 and absorb any liquids released inside the bag 1. In this way it is possible to protect the gluing points (indicated schematically with X in figure 2) used to form the lower base 4. Normally, in fact the glues used for making paper bags are soluble in the water present in the liquids released by the waste. This problem has strongly limited the diffusion of paper bags in the field of collecting organic waste. The absorption of the liquids by the bottom flap 3 also confπbυfes fo minimising the formation of unpleasant smells during the time the waste remains inside the bag.

An absorbent and, at the same time, compostable material suitable for making the bottom flap 3 is paper (or cardboard], for example of the same type mentioned above as regards the bag 1. In the case of the bottom flap 3, in order to increase its resistance, the weight of the paper may be heavier than that used for the bag 1 , for example about 150-180 g/m².

Figures 1 , I A, I B and 2 show the bag 1 with a flat bottom 4. In other words the lower base 4 of the bag shown is of the type known in the field with the name "flat bottom". It will be clear to the technician in the field that the bag 1 may also be realised with other types of bottom, depending on the final use of the bag. Figures 3-5 schematically show different blanks 2 for the production of the bag 1 , which differ in the part intended to form the lower base 4. In particular the blank 2 in figure 3 is similar to the blank shown in figure 2, but it differs from it in the different shaping of the bottom line 7 which has a greater number of "steps". In this way it is possible to increase the gluable surface and maximise the resistance of the bottom 4. Figure 4 shows a portion of a blank 2 for the formation of a bag 1 having a "square bottom". The reference number 8 indicates the creasing lines for forming the bottom. Figure 5 refers to a portion of a blank 2 for forming a bag 1 with a "crossed bottom". In this case too the reference number 8 indicates the creasing lines for the bottom. In general, the bag may present different shapes and it is not limited to only the types of bottom mentioned.

The bag 1 according to the present invention is simple to make, since if can be obtained from the blank 2 according to known techniques, and inexpensive, since the bottom flap 3 can be realised with minimum costs. The problems that may be encountered in using traditional containers are easily overcome. In fact the bag 1 is permeable to air, resistant to the weight of the content, resistant to any liquids released on the bottom 4 and it is biodegradable. In the collection of compostable organic waste, the permeability to air of the bag 1 allows for the activation of the normal oxidation processes, minimising the risks of rapid rotting of the waste, and therefore allows minimisation of the formation of unpleasant smells generated by the rapid decomposition of the organic material. The compost that can be obtained from the waste collected using the bag 1 is therefore a high quality compost. Thanks to the presence of the bottom flap 3, the bag 1 offers a greater resistance to the weight of the content than is found in traditional paper bags. Moreover, the absorbent capacity of the bottom flap 3 minimises the risks of breakage of the bag 1 due to the action of the liquids released by the waste and at the same time if reduces the formation of unpleasant smells developed by those liquids.

The paper or cardboard used to form the bag 1 contain lignin, a natural fibre which is particularly efficacious for obtaining a high quality compost.

The bag 1 may be made of highly biodegradable, if not completely biodegradable, materials, unlike bags made of corn starch. In fact the presence of the bottom flap 3 allows bags 1 to obtained which are sufficiently resistant for the collection of organic waste without it being necessary to add plastic materials to increase their resistance.

For the reasons listed above the bag 1 is particularly suitable both for collecting organic waste and for holding fresh foodstuffs. However its use is not limited to these sectors, for example the bag could be used in general commercial fields, in the plant nursery sector, etc.

Claims

1. Bag for collecting waste or fresh foodstuffs of the type with a lower base and side walls, erectable from a blank of paper material, folded and glued, characterised in that it comprises at its inside a bottom flap that may be moved between a non operative position, in which said bottom flap is substantially situated parallel to said side walls, and an operative position, in which said bottom flap is substantially parallel to said lower base, when said bag is in an erect configuration.

2. Bag according to claim 1 , characterised in that said bottom flap in said operative position at least partly overlaps said lower base to act as an element that supports the content of the bag.

3. Bag according to either one of the previous claims, characterised in that said bottom flap is fastened in a removable way to at least one part of the bag.

4. Bag according to claim 3, characterised in that said bottom flap is at least partly glued to a side wall of the bag.

5. Bag according to claim 3 or claim A₁ characterised in that said bottom flap can be turned onto said lower base of the bag, from the non operative position.

6. Bag according to any one of the previous claims from 1 to 5, characterised in that said lower base of the bag is of the type chosen among flat bottom, square bottom and crossed bottom.

7. Bag according to any one of the previous claims from 1 to 6, characterised in that said bottom flap is made of absorbent material.

8. Bag according to any one of the previous claims from 1 to 7, characterised in that said bottom flap and the bag itself are biodegradable and compostable.

9. Bag according to any one of the previous claims, characterised in that said bottom flap is made of paper material.

10. Bag according to any one of the previous claims, characterised in that said bottom flap and the bag itself are made, at least partly, of recycled paper. i l. Bag according to any one of the previous claims, characterised in that it is made of a material at least partly permeable to air. 12. Use of the bag according to any one of the previous claims for the collection of compostable waste. 13. Use of the bag according to any one of the previous claims as a container for fresh foodstuffs.