FR2959495A1 - Film for plastic bag e.g. biodegradable bag, to protect products from moisture, has inner layer comprising welding biopolymer that is fabricated from potato flour or starch, and adhesive layer formed between outer layer and inner layer - Google Patents

Abstract

The film (1) has an inner layer (2) comprising a welding biopolymer that is fabricated from potato flour or starch. The welding biopolymer is obtained from starch of maize, soy, rice, sorghum or yam. An adhesive layer (4) is formed between printable outer layer (3) and the inner layer. The outer layer includes paper and a printable non-welding biopolymer e.g. cellulose diacetate or triacetate. The outer layer is made of printable non-welding biopolymer. A biopolymer barrier layer is made of metallized cellophane.

Description

B09 / 4978 EN AxC / GBO Simplified joint stock company called: GASCOGNE SACK Film for biodegradable and / or compostable bag, and corresponding bag Invention of: Georges LOUPIT Film for biodegradable and / or compostable bag, and corresponding bag

The present invention relates to waterproof bag films that are biodegradable and / or compostable. It is known to use plastic bags consisting of an assembly of several folds or layers, and comprising at least one non-biodegradable plastic layer, for example a polyethylene layer. Such films may be composed for example of two or three plies: an outer layer of paper, a plastic layer, and optionally an inner layer of paper. The function of the paper layer or layers is to give the bag its mechanical strength, and to provide a printing medium, while the plastic layer serves to protect the contents of the bag from moisture. The bag may be shaped in a variety of ways to provide stability or desired capacity, and may also include a closure, such as a zipper or zipper type closure.

However, such bags do not meet the biodegradability and / or composting criteria, in particular because of the presence of the plastic layer, and must therefore pass through burial or incineration type dies during their destruction. An object of the present invention is therefore to provide a film for manufacturing bags, both to protect products from moisture, and to be biodegradable and / or compostable. For this purpose, in one embodiment, there is provided a film for a plastic bag, in particular for a biodegradable or compostable bag, comprising an inner layer comprising a solderable biopolymer, wherein the solderable biopolymer is made from potato starch. or from starch, for example corn, soya, rice, sorghum or yam. The replacement of the polyethylene layer with a layer of solderable biopolymer made from potato starch or from starch makes it possible to obtain a film that maintains sealing properties, while being biodegradable and / or compostable. . In particular, the film is free of non-biodegradable or non-compostable plastic layer.

According to standard NF EN 13432, a material is considered as biodegradable if, when it is placed for a period of not more than 6 months, in a soil, fresh water or salt water, at least 90% the starting mass of the material is degraded, that is to say if the biodegradation residues represent a maximum of 10% of the starting mass, and if the biodegradation residues do not have an ecotoxic effect on the middle. In addition, according to standard NF EN 13432, a material is considered compostable if, when it is placed for a duration of not more than 12 weeks in an industrial composter (in windrow or heap), at least 90% of the starting mass of the material is degraded, that is to say if the residues represent at most 10% of the starting mass, if the residues have a size less than 2mm, if the material does not have a negative effect on the composting process and if the residues do not have an ecotoxic effect on the compost.

Advantageously, the film comprises a printable outer layer, and at least a portion of the outer face of the outer layer is printed with a water ink. According to one embodiment, the film may also comprise an adhesive layer between the outer layer and the inner layer. The film may thus consist of: an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soya, rice, sorghum or yam a printable outer layer, an adhesive layer between the inner layer and the outer layer, and optionally ink with water on at least a part of said outer layer, and a means of closing.

According to one embodiment, the outer layer comprises cellulosic fibers, for example paper, a printable non-sealing biopolymer such as cellulose di- or tri-acetate, for example, or any other printable or non-printable non-sealing biopolymer.

Thus, the film may consist of: an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soya, rice, sorghum or yam, - a printable outer layer of cellulosic fibers, for example paper, cellulose di- or triacetate, - an adhesive layer between the inner layer and the outer layer, - and optionally ink to the water on at least a portion of said outer layer, and a closure means.

Advantageously, when the outer layer is printable non-welding biopolymer, the film may also comprise, between the inner layer and the outer layer, one or more additional layers of cellulosic fibers, in particular paper, and optionally one or more adhesive layers for attaching the additional layer or layers of cellulosic fibers together. Thus, the film may consist of: an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soya, rice, sorghum or yarn, - a layer of paper, - a first adhesive layer between the inner layer and the paper layer, - a printable non-sealing biopolymer outer layer, - a second adhesive layer between the paper and the outer layer, and optionally water ink on at least a portion of said outer layer, and a closure means.

In particular, an adhesive layer is associated with each additional layer of paper. The film may for example comprise three additional layers of paper. Thus, the film may consist of an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soybean, rice, sorghum or yam. a first layer of paper, a first adhesive layer between the inner layer and the first layer of paper, a second layer of paper, a second adhesive layer between the first layer and the first layer of paper. second layer of paper, - a third layer of paper, - a third adhesive layer between the second layer and the third layer of paper, - optionally a printable non-sealing biopolymer outer layer and a fourth layer adhesive between the third paper layer and the outer layer, and optionally water ink on at least a portion of said outer layer, and a closure means. According to one embodiment, the film also comprises, between the outer layer or the layer of paper, and the inner layer, a layer of barrier biopolymer, for example metallic cellophane or other barrier bioplastic. An adhesive layer may be associated with the barrier biopolymer layer. Thus, the film may consist of: an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soya, rice, sorghum or yam, - a barrier biopolymer layer, - a first adhesive layer between the inner layer and the barrier biopolymer layer, - a non-sealing printable biopolymer outer layer, - a second adhesive layer between the barrier biopolymer layer and the outer layer, and optionally water ink on at least a portion of said outer layer, and a closure means. Likewise, the film may consist of: an inner layer comprising a solderable biopolymer made from potato starch or from starch, for example corn, soya, rice, sorghum or yam, - a barrier biopolymer layer, - a first adhesive layer between the inner layer and the barrier biopolymer layer, - a paper layer, - a second adhesive layer between the biopolymer layer barrier and the paper layer, optionally a non-sealing printable biopolymer outer layer and a third adhesive layer between the paper layer and the outer layer, and optionally water ink on at least one part of said outer layer, and a closure means. The invention also relates to a plastic bag, in particular biodegradable and / or compostable, comprising a film as described above.

The bag may also include a closure means, zip type or zipper type. To form the bag, the films described above comprise an inner layer of welding biopolymer: thus, it is possible to give the bag the desired shape by welding between them different parts of the inner layer of the film. It is also possible to weld between them the inner layers of several films constituting the bag. The outer surface is formed of a printable layer, to allow the mention of marks, information, etc..

The barrier layer allows, when present, to limit or even eliminate the passage of the bag by electromagnetic radiation, especially light, but especially by gases and moisture, in order to avoid the degradation of certain products. .

Finally, the various additional layers of paper make it possible to increase the rigidity of the bag, in particular in order to adapt it to the type of product and the quantity of product intended to be kept in the bag. The invention will be better understood in the study of eight particular embodiments, taken as non-limiting examples and illustrated by the accompanying drawings, in which: - Figures 1 to 8 schematically show films according to the invention; and FIGS. 9 to 11 schematically represent bags according to the invention. In Figure 1, there is shown a first embodiment of a film 1 according to the invention. In this embodiment, the film 1 comprises an inner layer 2 of solderable biopolymer made from potato starch or from starch, for example corn, an outer layer 3 of printable non-sealing biopolymer, and an adhesive layer 4 between the inner layer 2 and the outer layer 3. FIG. 2 illustrates a second embodiment in which the elements identical to the first embodiment are referenced by the same numbers. In the second embodiment, the film 20 comprises an inner layer 2, a printable outer layer 3, a barrier layer 5, an adhesive layer 4 between the barrier layer 5 and the outer layer 3, and an adhesive layer 6 between the layer inside 2 and the barrier layer 5.

FIG. 3 illustrates a third embodiment in which elements identical to the previous embodiments are referenced by the same numbers. In the third embodiment, the film 30 comprises an inner layer 2, an outer layer 7 made of paper, and an adhesive layer 8 between the inner layer 2 and the paper layer 7. Figure 4 illustrates a fourth embodiment in which elements identical to the previous embodiments are referenced by the same numbers. In the fourth embodiment, the film 40 comprises an inner layer 2, a paper layer 7, an adhesive layer 8 between the inner layer 2 and the paper layer 7, an outer layer 3 of printable biopolymer, and an adhesive layer 4 illustrates a fifth embodiment in which elements identical to the preceding embodiments are referenced by the same numbers. In the fifth embodiment, the film 50 comprises an inner layer 2, an outer layer 7 made of paper, a barrier layer 5, an adhesive layer 8 between the barrier layer 5 and the paper layer 7, and an adhesive layer 6 between the inner layer 2 and the barrier layer 5. FIG. 6 illustrates a sixth embodiment in which the elements identical to the previous embodiments are referenced by the same numbers. In the sixth embodiment, the film 60 comprises an inner layer 2, a paper layer 7, a barrier layer 5, an adhesive layer 8 between the barrier layer 5 and the paper layer 7, an adhesive layer 6 between the layer 2 and the barrier layer 5, an outer layer 3 of printable biopolymer, and an adhesive layer 4 between the paper layer 7 and the outer layer 3. FIG. 7 illustrates a seventh embodiment in which elements identical to the embodiments precedents are referenced by the same numbers. In the seventh embodiment, the film 70 comprises an inner layer 2, a paper layer 7, an adhesive layer 8 between the inner layer 2 and the paper layer 7, a paper layer 9, an adhesive layer 11 between the paper layer 7 and the paper layer 9, an outer paper layer 12, and an adhesive layer 13 between the paper layer 9 and the paper layer 12. Fig. 8 illustrates an eighth embodiment in which like elements the previous embodiments are referenced by the same numbers. In the eighth embodiment, the film 80 comprises an inner layer 2, a paper layer 7, an adhesive layer 8 between the inner layer 2 and the paper layer 7, a paper layer 9, an adhesive layer 11 between the paper layer 7 and the paper layer 9, a paper layer 12, an adhesive layer 13 between the paper layer 9 and the paper layer 12, a printable biopolymer outer layer 3, and an adhesive layer 4 between the layer paper 12 and the outer layer 3. Figure 9 illustrates a first example of bag 90, called "square", consisting of a film according to one of the eight embodiments described above. The film is folded on itself so as to have four planes whose edges are welded together, forming a cavity fillable by different products. A first plane is formed by the front face 14 of the bag, which is parallel to a rear face 15. Between the two faces 14, 15, there are two bellows 16, 17 whose width is smaller than that of the front and rear faces. The bottom 18 consists of parts of the four faces 14, 15, 16, 17 folded and welded so that when filling the bag, it takes the form of a rectangular parallelepiped whose top is open. The shape of the opening is also parallelepipedal in the case of the bag 90. Finally, a closure means (not shown) can then be mounted at the top opening, for example a zip or a zipper.

FIG. 10 illustrates another example of bag 100, called "single layer" or "single lip", the opening of which is composed of only two thicknesses. The bag 100 is similar to the bag 90 but in which the bellows 19 are cut at a distance from the opening of the bag, the front 14 and rear 15 of the bag being wound together. A closure means (not shown) such as a zip or zipper can be inserted before the front and back faces are wound. FIG. 11 illustrates another example of bag 110, called "three welds without bellows", similar to case 90 but in which the bellows have been removed. The front 14 and rear 15 of the bag are welded to each other along the edges and at the bottom. The bag can be closed after filling by welding the front and rear faces at the top opening. Thus, the films described above allow the manufacture of different types of bags, having the property of being biodegradable or compostable. However, the invention is not limited to the bags described above, but also applies to other types of bags, such as bags known as "pinch", "SOS (self opening and standing)", or "open mouth" And more generally to any type of bag formed from a film whose inner surface is welded on itself to give the shape of the bag, and whose outer surface makes it possible to print indications thereon.

Claims (12)

REVENDICATIONS1. Plastic bag film, especially for a biodegradable or compostable bag, comprising an inner layer (2) comprising a solderable biopolymer, characterized in that the solderable biopolymer is made from potato starch or from starch. The film of claim 1 wherein the solderable biopolymer is made from corn starch, soybean, rice, sorghum or yam. 3. The film of claim 1 or 2 further comprising an outer layer, preferably printable, and optionally an adhesive layer between the outer layer and the inner layer. The film of claim 3 wherein the outer layer comprises paper, printable non-sealing biopolymer, for example, cellulose di- or tri-acetate, or a non-printable non-sealing biopolymer. 5. Film according to claim 4 wherein the outer layer (3) is printable non-sealing biopolymer, the film also comprising, between the inner layer and the outer layer, one or more additional layers of paper. The film of claim 5 wherein an adhesive layer is associated with each additional layer of paper. The film of claim 5 or 6 comprising an additional layer of paper. 8. The film of claim 5 or 6 comprising three additional layers of paper (7, 9, 12). 9. Film according to one of claims 3 to 4 further comprising, between the outer layer and the inner layer, a layer of barrier biopolymer (5), for example metallophane cellophane. The film of claim 7 further comprising, between the paper layer and the inner layer, a barrier biopolymer layer. 11. Film according to claims 9 or 10 wherein an adhesive layer is associated with the barrier biopolymer layer. 12. Plastic bag, in particular biodegradable and / or compostable, comprising a film according to one of claims 1 to 11.