Bagged food pad

Abstract

The invention relates to a bagged food mat for use in a food tray to absorb and entrap liquids, comprising an absorbent core (11) enclosed in a bag (10, 12) formed by a first bag layer (10) and a second bag layer (12) connected by a bond (13), wherein the absorbent core (11) comprises two layers (11A, 11B) comprising a cellulose-based support layer (11B) having a grammage between 12-50 g / m 2 , and wherein the first and second bag layers (10, 12) have a grammage between 10-70 g / m 2 , preferably 12-50 g / m 2 , and wherein the tensile wet strength of at least the first bag layer (10), preferably both layers (10, 12), is between 5-50% of the tensile dry strength of the at least first bag layer (10).

Description

Technical Field

[0001] This invention relates to a pouch-type food pad, for example, used in food trays to absorb and trap liquids, comprising an absorbent core encapsulated within a bag formed by a first bag layer and a second bag layer connected by a joint. All materials constituting the pouch-type food pad are natural and cellulose-based, fully recyclable in paper recycling cycles, and compostable. Background Technology

[0002] Food trays with highly absorbent pads are commonly used to improve the shelf life and freshness of various foods, such as meat, poultry, fish, and fruit, by absorbing excess liquid through the pads. Many different types of food pads exist, such as monolithic laminated food pads and pouch food pads. The advantage of pouch food pads is that they eliminate the risk of absorbent material adhering to the food. This is achieved by using a permeable material in the pouch, which comprises a first layer and a second layer bonded together around an absorbent core. The layer in contact with the food is permeable and also resistant to moisture / liquid, thus eliminating any part of the pad from adhering to the food. In most cases, a superabsorbent polymer (SAP) or superabsorbent fiber (SAF), usually combined with an adhesive, is used as the main material for such pouch food pads, such as absorbent laminates known from US-A-2019275781. The use of food pads has been widely accepted in the market.

[0003] However, it is still desirable that food storage can be carried out using more environmentally friendly materials, preferably renewable, recyclable and compostable materials, US-A-2019275781.

[0004] A bag-type food mat is known from DE-U-202010014178, aiming to provide an environmentally friendly alternative, comprising an absorbent core in the form of a highly absorbent airlaid material free of SAP / SAF, and wherein the bag includes a breathable, biodegradable film, wherein PLA is proposed for use in both the core and the bag film. However, since PLA is not naturally biodegradable and recycling systems for PLA are absent in most areas, this bag-type food mat does not align with ambitious goals regarding sustainability. The mixing of bioplastics with oil-based plastics and the contamination of these plastics' recycling systems is also a common problem. Therefore, from this perspective, other alternatives are also needed.

[0005] The choice of product materials is clearly an important aspect of recyclability. However, contamination (such as contamination from contact with food) is also an aspect that can pose difficulties to the recycling process. Summary of the Invention

[0006] The object of this invention is to provide a paper-based bag-type food mat that is easy to recycle in the paper flow and also meets high requirements regarding shelf life and the appearance of food freshness, which is achieved by the bag-type food mat according to the independent claims.

[0007] Furthermore, the combination of materials used in the food mats according to the invention enables effective facilitation of recycling, which is achieved through the selection of materials, the design of their combination, and the selection of their structure, for example, by providing the ability to effectively clean the mats before delivery to the recycling process.

[0008] It has been found that a cost-effective and sustainable solution can also be provided by using the bag-type food pad according to the invention.

[0009] Preferred embodiments of the present invention have the characteristic of providing good rinsing ability, for example, by using water.

[0010] Furthermore, the material used in the layers 10 and 12 of the bag 10 of the food pad 1, at least on one "contact side," preferably both sides, should preferably have sufficient wet strength to remain intact when removed from the food without leaving any residue. Another advantage is that the side not in contact with the food remains intact when removed from the tray or carrier, for example, if separation is required. Tests show that 10-30 g / m 2 Tea bag paper (bleached and unbleached), 15-60g / m³ 2 The preferred filter paper is 20-40 g / m². 2 and 10-50g / m 2 Kraft paper (bleached and unbleached) meets this desired property.

[0011] Furthermore, under humid conditions, the lamination strength of the joint 13 of the bag 10 of the food pad 1 is preferably sufficient to allow food to be removed without delamination. More preferably, for example, the lamination strength should also be sufficient to allow the pad to be rinsed and squeezed with water without causing the joint to delaminate, so as to facilitate the recycling process. Tests (using test pieces with a joint length of 25 mm) show that, under humid conditions, the lamination strength of the joint 13 is preferably at least 0.4 N / 25 mm, more preferably 0.5 N / 25 mm.

[0012] However, the materials 10, 12, and 11 of the food mat 1 should preferably not be too wet-strong to facilitate decomposition in later stages of the recycling process. Tests show that, under wet conditions, the lamination strength of the bond 13 should preferably be less than 5 N / 25 mm, more preferably less than 3 N / 25 mm.

[0013] Furthermore, preferably, the bag layers 10 and 12 (i.e., the surface materials) are sufficiently permeable to liquid to facilitate rinsing, preferably in water, to achieve the desired rinsing level. Tests show that, preferably, at least one of the layer materials 10 and 12 should have a concentration of 10-30 g / m³. 2 Tea bag paper or 15-60g / m 2 The filter paper, one layer of which can be 10-50g / m 2 The kraft paper, more preferably, has two layers of material 10 and 12 with a strength of 10-30 g / m². 2 Tea bag paper and / or 15-60g / m 2 Filter paper. Tests on tea bag paper suggest that unbleached paper may offer better rinsing power than bleached paper.

[0014] Specific tests show that all of the above materials / combinations have good rinsing results, that is, at least 75% of the absorbent material can be rinsed away, and even up to 90% or more in the preferred range mentioned above.

[0015] Furthermore, verification tests on recyclability were conducted according to European standard EN 13430, which demonstrated that all the aforementioned bag layer materials are suitable for recycling, for example, decomposing well after 15 minutes. All tested materials also exhibited favorable scrap rates, preferably below 15%.

[0016] According to another aspect of the invention:

[0017] - The tensile strength of the at least first bag layer (10) is measured under wet conditions in a tensile strength tester under wet conditions, and the tensile strength is between 0.5 N / 50 mm and 4 N / 50 mm, preferably 0.8-2 N / 50 mm.

[0018] - The absorbent core (11) includes a high-absorbency layer (11A), which comprises 15-100% mechanical pulp, preferably CTMP, with a basis weight of 50-1300 g / m³. 2 This can optimize absorption and / or processing and / or cost, wherein preferably, the thickness (TA) of the high absorption layer (11A) is at least twice the thickness (TB) of the support layer (11B);

[0019] - The density of the absorber core (11) is 50-300 g / dm³. 3 More preferably 80-225g / dm 3 This can optimize absorption and / or processing and / or cost;

[0020] - The entire food mat (1) and preferably also includes a food tray with the food mat, made of recyclable natural fiber material, which optimizes use and recycling. Attached Figure Description

[0021] The invention will be described in more detail below with reference to the accompanying drawings, in which:

[0022] Figure 1 A food tray containing a bag-type food pad is shown, and

[0023] Figure 2 A schematic perspective view of a bag-type food pad according to the present invention is shown. Detailed Implementation

[0024] exist Figure 1 The image shows a food tray 2 of a known type, used as an exemplary application of the food mat 1 according to the invention. A bag-type food mat 1 according to the invention is placed at the bottom inside the food tray 2. Clearly, any kind of food tray (and other devices for achieving similar purposes) can be used with the food mat 1. However, special advantages, at least in relation to recycling, can be obtained by using a food tray made of recyclable materials such as cellulose.

[0025] exist Figure 2 The image shows a pouch-type food mat 1 according to the invention, having a first pouch layer 10, a second pouch layer 12, and a core 11. The first and second pouch layers 10 and 12 are connected at their edges by a joint 13, which is preferably continuous. It is foreseeable that one side of the mat can be folded, i.e., one side of the pouch 10 and 12 is thus formed in a folded form.

[0026] Within the space formed by bags 10, 12, and 13, a core 11 of highly absorbent material is placed. The highly absorbent material 11 is a material free of any significant amounts of superabsorbent polymer (SAP), superabsorbent fiber (SAF), or PLA. The core 11 also does not contain any significant amounts of binding material. Instead, the core 11 comprises high-yield natural fibers, preferably containing at least 15%, more preferably 100%, of high-yield natural recyclable fibers. The core is preferably produced by an air-laid method, or by an air-laid method or a method providing similar properties in a previous step, as described in WO99 / 33420A1, for example. Another possible method to avoid the use of any adhesives or thermal bonds can be found in EP0833977B1.

[0027] Core 11 includes a high-absorbency layer 11A comprising a chemical or mechanical pulp. Preferably, the high-absorbency layer 11A comprises 15-100%, more preferably 55-100%, and most preferably 75-100% mechanical pulp. The most preferred mechanical pulp is CTMP. The basis weight of the high-absorbency layer 11A is 50-1300 g / m³. 2 Between 100-1200 g / m³ is preferred. 2 Between 200-800 g / m³, more preferably between 200-800 g / m³ 2Between 12-50 g / m². The basis weight of the cellulose-based support layer 11B is between 12-50 g / m². 2 Between 15-25g / m 2 .

[0028] Core 11 can be produced, for example, by compressing it to a thickness between 1 and 15 mm between rollers arranged in a suitable manner. This produces a density of 50-300 g / dm³. 3 Or more preferably 80-225g / dm 3 The core.

[0029] The thickness TA of the high-absorption layer 11A is preferably significantly greater than the thickness TB of the support layer 11B, at least twice the thickness TB of the support layer 11B. Preferably, TA > 5TB, more preferably, TA > 8TB.

[0030] Bag materials 10 and 12 are materials that do not contain any significant amount (preferably none) of superabsorbent polymer (SAP) or superabsorbent fiber (SAF) or PLA, and contain at least 80%, more preferably 100%, of paper-recyclable raw material fibers, i.e., cellulose or equivalent natural fibers or bag materials derived from natural fibers. Examples of such natural raw materials are preferably cellulose fibers primarily combined with less than 50% hemp fiber and / or banana fiber.

[0031] The weight of bag material 10 and 12 is between 10-70 g / m³. 2 The optimal value is between 15-50 g / m³. 2 Between. The first layer 10 of bag 1 is for direct contact with food (such as meat, fish, etc.).

[0032] The second layer 12, which is not intended for direct contact with food, can be made of the same material as the first layer 10. However, it can be made of a different material than the first layer 10 and still achieve the basic function of the invention. However, in a preferred embodiment, the entire pouch-type food pad should be made of virgin, recyclable paper fibers, from a variety of raw materials such as kraft paper, filter paper, cellophane, tea bag paper, and tissue paper.

[0033] One or two of layers 10 and 12 can be perforated to ensure high liquid permeability.

[0034] If the material is not perforated, it is advantageous to choose a material / combination with sufficient permeability to promote absorption and good flushing performance.

[0035] The material used in the first layer 10, and preferably also in the second layer 12, should have a certain wet strength to avoid material decomposition on food surfaces. The tensile strength of a 50mm wide strip of material is measured under wet conditions in a tensile strength tester, and the tensile strength should be between 0.5 N / 50mm and 4 N / 50mm, preferably between 0.8 N / 50mm and 2 N / 50mm. This corresponds to 5-50% of the tensile strength of the material itself under dry conditions. Preferably, materials in which the tensile strength under wet conditions is between 10-30% of the tensile strength under dry conditions are used. The lower limit of the tensile strength range is based on the material strength under the intended use conditions, while the upper limit is to maximize yield during the recycling process.

[0036] The joint 13 is designed such that its strength is sufficient under both wet (during use) and dry (before use) conditions, and this strength can be varied according to specific needs / expectations. Layers 10 and 12 can be bonded together with one or two continuous layers of hot melt adhesive. The tensile strength of the bond under wet conditions should be at least 10-30% of the tensile strength of the bond under dry conditions. Preferably, the tensile strength is balanced in such a way that it matches (at a similar level) the strength of layers 10 and 12 under wet conditions. This joint strength can be measured on a 25 mm strip of material using a tensile strength tester.

[0037] In some applications, the strength of the joint can exceed the strength of layers 10 and 12 under wet conditions, resulting in material breakage of the bag material rather than decomposition of any of the layers 10 and 12.

[0038] Because this invention enables environmentally friendly, all-paper, recyclable, and compostable food packaging, it offers surprising advantages compared to existing food packaging technologies. Tests have shown that using the bag-type food pad 1 according to the invention in food trays 2 used for storing meat can meet high demands.

[0039] Furthermore, the verification of recyclability is conducted in the following order according to European Standard EN 13430:

[0040] 1. Pulping is performed under so-called neutral conditions (standard ISO 5263-1) (pulping time 15 minutes, concentration 3%, pulping temperature 40 degrees Celsius, no added chemicals).

[0041] 2. Visually observe the color of the fiber suspension and water.

[0042] 3. Remove unwanted materials (TAPPIANSI T275 sp-18).

[0043] Somerville installation.

[0044] 4. Optional cleaning. It was not used because it was unnecessary.

[0045] 5. Appearance of the manufactured handmade paper pieces (Standard NF EN ISO 5269-2)

[0046] All tested materials and combinations of materials showed a scrap rate of less than 15%, which is very favorable and consistent with newspaper materials.

[0047] It will be apparent to those skilled in the art that the above are merely examples of the use of the inventive food mat according to the present invention. For example, there are various applications in which the food mat according to the present invention can achieve similar beneficial functions together with a food tray.

Claims

1. A bagged food pad for use in a food tray to absorb and contain liquids, comprising an absorbent core enclosed in a bag, the bag being formed from a first bag layer and a second bag layer connected by a bond, characterised in that, The entire food mat is made of natural virgin fibre material that is easy to recycle, the absorbent core comprises two layers, the two layers comprising a cellulose-based support layer with a grammage between 12-50 g / m 2 and a high-absorbent layer of chemical or mechanical pulp, and wherein the first and second bag layers have a grammage between 10-70 g / m 2 and wherein the tensile wet strength of the first bag layer is between 5% and 50% of the tensile dry strength of the first bag layer, wherein the lamination strength of the joint under wet conditions is at least 0.4 N / 25 mm and less than 5 N / 25 mm, and wherein the first and second bag layers are permeable.

2. The pouch food mat of claim 1, wherein The first and second bag layers have a grammage of 12-50 g / m 2 .

3. The pouch food mat of claim 1, wherein, The tensile wet strength of the first bag layer is between 10% and 30% of the tensile dry strength of the first bag layer.

4. The pouch food mat of claim 1, wherein, The tensile wet strength of both layers is between 5% and 50% of the tensile dry strength of the first bag layer.

5. The pouch food mat of claim 1, wherein, The tensile wet strength of both layers is between 10% and 30% of the tensile dry strength of the first bag layer.

6. The pouch food mat according to any one of the preceding claims, characterized in that, The tensile strength of the first bag layer is between 0.5 N / 50 mm and 4 N / 50 mm, measured on a 50 mm wide strip of material in a tensile strength tester under wet conditions.

7. The pouch food mat of claim 6, wherein, The tensile strength of the first bag layer is between 0.8 N / 50 mm and 2 N / 50 mm, measured on a 50 mm wide strip of material in a tensile strength tester under wet conditions.

8. The pouch food mat according to any one of claims 1 to 5, characterized in that, The high absorption layer comprises 15-100% of mechanical pulp, with a grammage of 50-1300 g / m 2 between.

9. The pouch food mat of claim 8, wherein, The high absorbent layer comprises 55-100% mechanical pulp.

10. The pouch food mat of claim 9, wherein, The high absorbent layer comprises 75-100% mechanical pulp.

11. The pouch food pad of claim 10, wherein, The mechanical pulp is CTMP.

12. The pouch food mat of claim 8, wherein, The high absorption layer has a grammage between 100 and 1200 g / m 2 .

13. The pouch food mat of claim 12, wherein, The high absorption layer has a grammage of 200-800 g / m 2 .

14. The pouch food mat of claim 3, wherein, The thickness of the high absorbent layer is at least twice the thickness of the support layer.

15. The pouch food pad of claim 14, wherein, The thickness of the high absorbent layer is more than five times the thickness of the support layer.

16. The pouch food pad of claim 15, wherein, The thickness of the high absorbent layer is more than eight times the thickness of the support layer.

17. The pouch food mat according to any one of claims 1 to 5, characterized in that, The support layer has a grammage between 15 and 25 g / m 2 .

18. The pouch food mat according to any one of claims 1 to 5, characterized in that, The density of the absorbent core is 50-300 g / dm 3 .

19. The pouch food mat of claim 18, wherein, The density of the absorbent core is 80-225 g / dm 3 .

20. The pouch food mat according to any one of claims 1 to 5, characterized in that, The material of at least one of the bag layers is a tea bag paper having a grammage of 10-30 g / m 2 2.

21. The pouch food mat according to any one of claims 1 to 5, characterized in that, The material of at least one of the bag layers is a filter paper having a grammage of 20-50 g / m 2 .

22. The pouch food pad of claim 20, wherein One bag ply is a kraft paper having a basis weight of 10-50 g / m 2 .

23. The pouch food mat of claim 21, wherein, One bag ply is a kraft paper having a basis weight of 10-50 g / m 2 .

24. The pouch food mat of claim 20, wherein, The material of the two bag layers is tea bag paper having a grammage of 10-30 g / m 2 2.

25. The pouch food pad of claim 21, wherein, The material of the two bag layers is filter paper having a grammage of 20-50 g / m 2 2.

26. The pouch food mat according to any one of claims 1 to 5, wherein, The bond has a laminate strength under wet conditions of at least 0.5 N / 25 mm and less than 3 N / 25 mm.

27. The pouch food mat according to any one of claims 1 to 5, wherein, The level of waste of the recycled food pad is below 30%.

28. The pouch food mat of claim 27, wherein, The level of waste of the recycled food pad is below 25%.

29. The pouch food mat of claim 28, wherein, The level of waste of the recycled food pad is below 20%.

30. The pouch food mat according to any one of claims 1 to 5, wherein, The material density of the material of at least one of the bag-in-bag layers is less than 0.8 kg / dm 3 .

31. The pouch food mat of claim 30, wherein, The material density of the material of both bag layers of the bag-in-bag layer is less than 0.8 kg / dm 3 .

32. The pouch food mat of claim 27, wherein, The material density of the material of at least one of the bag-in-bag layers is less than 0.65 kg / dm 3 .

33. The pouch food mat of claim 32, wherein, The material density of the material of at least one of the bag-in-bag layers is less than 0.5 kg / dm 3 .

34. Food tray comprising a bagged food mat according to any one of claims 1 to 33, characterized in that, The food tray is made of a raw material that is recyclable.

35. The food tray of claim 34, wherein, The food tray is made of cellulose.

36. The food tray of claim 34, wherein The food tray is made of equivalent natural fibers.

37. The food tray of claim 34, wherein The food tray is made of a bag material derived from natural fibers. The food tray is made of a bag material derived from natural fibers.

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