MXPA03005457A - Absorbent pad for food products. - Google Patents

Abstract

An absorbent pad to be used in food products packages. Said pad effectively absorbs juices or liquids from food, and is characterized in that it comprises an upper and a lower plastic layers; an intermediate layer and optionally a fabric or absorbent paper layer. The intermediate absorbent layer is formed by an absorbent material and absorbent fibers, which are homogeneously distributed along the same. At least one of the plastic layers is perforated so as to allow the liquid to flow towards the absorbent layer; the said perforations are conical-shaped in order to avoid the liquid to be absorbed by the food again. The pad may include a seal at the periphery thereof, or the upper and lower plastic layers may be joined therebetween but only by their two opposite ends. The disclosure embodies a plurality of protruding channels, which are crosslinked therebetween; the said channels along with the superabsorbent fibers facilitate the liquid distribution all over the absorbent layer.

Description

ABSORBENT PAD FOR FOOD PRODUCTS FIELD OF THE INVENTION The present invention relates to an absorbent pad designed for use in trays and packages of food products such as chicken, fish and meat, the pad incorporates superabsorbent fibers to provide a better absorption of juices or liquids emanated by the product, improving its appearance and its shelf life.

BACKGROUND OF THE INVENTION Some food products such as fish, livestock meat and poultry are distributed for sale in individual trays, where the product is usually covered with a transparent plastic layer. Said layer protects the food from the outside and allows the consuming public to see its content. While this type of packaging protects the product from external contamination, there is "a risk of internal contamination by the presence of juices or liquids emanating from the product, which favor the growth of microorganisms." In addition, juices or liquids inside the package create an unpleasant or unattractive impression for the consumer.

In order to solve or minimize the above mentioned problems it is very common to use absorbent pads, which are placed between the support tray and the product, to absorb the liquids or juices emanated. However, most absorbent pads alone are not able to fully absorb the juices or liquids and these remain in contact with the product, favoring its deterioration. As a result of the foregoing, U.S. Patent No. 3,026,209 proposes to incorporate a plastic film or layer on the top of the pad. Juices or liquids penetrate the pad at the bottom and the side edges of the pad, while the top layer of plastic prevents the return of liquids to the food. Although the plastic layer forms a barrier between the product and the liquids, it is inevitable that a part of the liquid remains in contact with the food, favoring the development of microorganisms. Other more recent pads include the use of an absorbent pad with two layers of plastic, upper and lower, which form a peripheral seal and where one of the layers is perforated, so that the liquid penetrates, either below or above. of the pad. For example, U.S. Patent Nos. 4,275,811; 4,321,997; 4,382,507 and 4,410,578 propose to perforate preferably the lower layer. Unfortunately, a disadvantage of these pads is that liquids or juices are generally trapped between the upper non-perforated layer and the product, favoring the deterioration of the food. In other cases it is proposed to include holes in the upper layer or even in both layers, however, when the pad is pressed, the juice or liquid leaves the pad towards the product. It has been found that one way to overcome the aforementioned drawbacks is to incorporate granules of a superabsorbent material into the pad to increase the liquid retention capacity. In this regard, U.S. Patent Nos. 4,960,621; 5,022,945 and 5,055,332 refer to an absorbent pad and a method for its manufacture. The pad has upper and lower plastic layers, wherein at least one of the plastic layers is perforated. The superabsorbent granules improve the absorption capacity of the pad, so that the absorbed liquid is retained even when pressure is applied to the pad. In order to distribute the superabsorbent granules homogeneously within the pad, these patents propose to use the spaces formed between a plurality of absorbent fibers of the pad and to fix the particles in a network of cellulose fibers and thermoplastic fibers, said network formed by a thermoagglutination process. Although pads with superabsorbent granules present important advantages, it is necessary to use the thermoplastic fibers to retain the granules. Still retained, the granules can be detached from the fiber web, for example, during transport, storage and handling of the pads, causing the eventual accumulation of granules at the corners or at the ends of the structure. In addition, the granules can block the orifices of the upper and / or lower layers of the pad and can even leave it, contaminating the food. Another disadvantage is that, during the manufacture of the pads, a part of the superabsorbent granules can accumulate somewhere in the meshes or in other parts of the equipment used in the process, deteriorating their operation. To overcome the aforementioned drawbacks, the present invention proposes to incorporate, instead of granules, superabsorbent fibers of acrylic acid polymer, acrylate polymer, isocyanate polymer or carboxymethyl cellulose in a pad, wherein the pad includes top and bottom layers of plastic and where at least one of these layers is perforated. Unlike granules, fibers can be more easily retained within the structure, without the need to use other synthetic fibers.

By being retained efficiently, it is unlikely that the fibers will exit through the holes in the upper and / or lower layers of the pad. The superabsorbent fibers allow to distribute the liquids in a more efficient way, because they serve as conductors of liquid and the absorbent material is better used than using granules. They also increase the speed of absorption with which, in conditions of display of trays, the retention is greater and faster. On the other hand, with the granules, the absorption of liquids is punctual, causing the saturation of liquid in a localized area of the absorbent layer. In addition, even when the food packaging is placed for sale in a slightly inclined form, the fibers allow the liquid to be distributed throughout the thickness and surface of the pad, thanks to the fact that they communicate with each other. The pad of the present invention also has channels throughout the absorbent body, which generate a plurality of cells formed in relief. The channels act in conjunction with the superabsorbent fibers to distribute the liquid efficiently. These channels, which are achieved by pressure and heat, form areas of high density. Absorbent material and superabsorbent fibers. The fibers intertwine with each other and with the absorbent material form highways that feed the cells. In addition, the communication between one cell and another to distribute the liquid is better than when using granules, thanks to the absorption surface offered by the fibers.

OBJECTIVES: 1. Provide an absorbent pad for food products such as beef and poultry meat, fish, cheese and the like, which allows absorbing liquids emanating from the product. 2. Provide an absorbent pad for food products, including superabsorbent fibers to absorb and retain liquids efficiently. 3. Provide an absorbent pad for food products, where the superabsorbent material is evenly distributed throughout the pad. 4. Provide a pad as described above, which allows to absorb liquids regardless of whether the pad is inclined during the display of the product on the shelf. 5. Provide a pad as described above, whose absorbent components are retained efficiently in the structure to prevent contamination of the food. 6. Provide a pad as described above, including an engraving or relief on the absorbent body that helps distribute liquids throughout the structure. These and other more specific objectives will be apparent and disclosed later during the detailed description of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the nature and objectives of the present invention, reference is made to the following detailed description in conjunction with the accompanying drawings, wherein: Figure 1 is an exploded view of the components or layers that form the absorbent pad of the present invention. Figure 2 shows a perspective view of the preferred embodiment of absorbent pad, assembled and ready for use. Figure 3 constitutes a cross-sectional side view of the pad, taken from a cut on line X-X of the pad of Figure 2, showing the layers of the absorbent pad. Figure 4 is a perspective view of the pad with a food product placed thereon, to constitute the preferred use proposed in the present invention.

Figures 5a shows a perspective view of a first alternative embodiment for absorbent pad of the present invention. Figure 5b shows a cross-sectional side view of the pad of figure 5a, taken from line X-X. Figure 6a shows a perspective view of a second alternative embodiment for absorbent pad of the present invention. Figure 6b shows a cross-sectional side view of the pad of figure 6a, taken from line X-X.

DETAILED DESCRIPTION OF THE INVENTION The absorbent pad for food products of the present invention is identified in the figures with the number (10). As seen in Figure 1, the pad (10) is formed by two thin layers of plastic, upper (20) and lower (21), as well as an intermediate absorbent layer (30) of greater thickness and a layer of fabric or paper (31) that is not woven or incorporated into the intermediate layer (30), but s £ is adjacent. It should be mentioned that the fabric or paper layer (31) may be absent from the pad without departing from the scope of the present invention. At least one of the two layers of plastic (20) and (21) has a plurality of holes (28) evenly distributed throughout its surface. Figure 2 shows' the absorbent pad (10) of the preferred embodiment, already assembled and ready for use. On the other hand, figure 3 presents a cross-sectional cut of the pad (10), showing the upper (20), lower (21), intermediate (30) layers and the paper or fabric layer (31), superposed . The function of the plastic layers (20) and (21) consists mainly in forming a barrier between the food and the absorbent layer (30), preventing the return of the liquids to the food, as well as physically retaining the intermediate absorbent layer. (30) and the fabric or paper layer (31). In turn, the absorbent layer (30) has the function of absorbing and retaining the juices or liquids emanating from the food product. To retain the intermediate absorbent layer (30) to the paper or fabric layer (31) in the middle of the plastic layers (20) and (21), a seal can be formed at least between two opposite lateral edges of said layers. of plastic, or else, this seal may be absent. This will be explained in more detail below. As shown in Figure 2, in the preferred embodiment, the plastic layers (20) and (21) are joined by means of pressure, heat or adhesive means along all their side edges to form a peripheral seal. However, depending on the use that is given to the pad (10), a seal can also be formed using only two opposite lateral ends of the plastic layers. Even this seal may be absent in the pad, in which case the coupling of the layers is performed by means of ultrasound or adhesives. The possible embodiments for the pad of the present invention will be described later. The intermediate absorbent layer (30) is formed by absorbent materials, which are selected, among others, from cotton fibers and their derivatives, cellulose fibers and their derivatives, as well as polyurethanes (sponges). Also included is a plurality of superabsorbent fibers arranged in a homogeneous manner throughout the layer (30), which intertwine with each other and are retained by the other absorbent materials mentioned above. Adjacent to the intermediate layer (30) is the fabric or paper layer (31). The latter, preferably, is also adjacent to the perforated plastic layer (21). The superabsorbent fibers are capable of absorbing and retaining juices or liquids emanating from the food product within the intermediate absorbent layer (30). The material constituting the superabsorbent fibers may be, for example, an acrylic acid polymer, acrylate polymer, isocyanate polymer or carboxymethyl cellulose, the former being the preferred material.

It has been found that an absorbent layer containing 70 to 100% cellulose or other absorbent material and 0 to 30% superabsorbent fiber allows to absorb liquids effectively. Preferably, ranges from 2 to 30% of superabsorbent material and the remainder formed by absorbent material can be handled, however, the preferred percentage composition consists of 10% superabsorbent fiber and 90% absorbent material. As seen in Figure 1, the intermediate layer (30) has a plurality of channels (42) that intersect, formed in relief by pressure and by heat in the absorbent body, said channels form zones of high density of absorbent material and superabsorbent fibers. The channels (42) define a plurality of cells (44), whose thickness is greater than that of the channels (42). The channels (42) facilitate the distribution of the liquid over the entire surface of the absorbent layer (30), since they form zones of high density of absorbent material and superabsorbent fibers. These fibers intertwine with each other and form absorbent material to form highways that feed the cells (44). In addition, thanks to the presence of superabsorbent fibers, the communication between cell and cell to distribute the liquid is very efficient. The upper (20) and lower (21) plastic layers are made of polyethylene, as it is a water-impermeable material, although other polymers such as polypropylenes, PVC, polystyrenes and non-woven polymers can be used. In the preferred embodiment of the present invention, only the lower layer (21) is perforated; the non-perforated layer (20) is adhered by its inner face preferably to the fabric or paper layer (31). It should be noted that, if the fabric or paper layer (31) is absent from the pad, the perforated layer (21) is attached directly to the absorbent intermediate layer (30). The perforations (28) of the lower layer (21) have a cone-like shape, the tip of which is directed towards the paper or fabric layer (31) and / or towards the intermediate layer (30) of the pad (see figure). 3) . The conical shape of the perforations (28) favors the passage of liquids or juices that are released from the food into the interior of the pad, where they are retained by the absorbent layer (30). At the same time, this conical shape substantially prevents the liquid from returning to the food. Preferably, the absorbent pad (10) has the same shape as the bottom of the tray or plate on which the food is placed and the dimensions of the pad are equal to or less than those of the bottom of the tray. For example, in the preferred embodiment, the pad has a rectangular shape, so that it can be placed at the bottom of the tray (25) that will house the food product (29) (see Figure 4).

The pad (10) of the present invention can be used in trays and packages of food products such as chicken, fish and meat. As mentioned above, there are other embodiments for the pad (10) of the present invention, which are shown in Figures 5a, 5b and 6a and 6b, Figure 5a shows a perspective view of an alternative pad mode Absorbent, wherein the two layers of plastic (20) and (21) have holes (28) and are joined at their edges to form a peripheral seal.

Figure 5b shows a cross section of the pad of figure 5a. Figure 6a shows a perspective view of another alternative embodiment of absorbent pad, wherein only one of the plastic layers (20) and (21) is perforated and wherein the two plastic layers are joined by two opposite edges. Figure 6b shows a cross section of the absorbent pad of Figure 6a.

Claims (20)

1. CLAIMS: 1. An absorbent pad for use in trays and packages of food products such as chicken, fish and meat, including: two layers of plastic, upper and lower, wherein at least one of the two plastic layers has a plurality of holes or perforations distributed evenly over its entire surface; an intermediate absorbent layer disposed between the upper and lower plastic layers, said layer having a greater thickness than the upper and lower plastic layers; and a layer of fabric or paper that is not woven or incorporated into the intermediate layer, but adjacent to the latter, wherein: the intermediate layer is formed by absorbent materials and a plurality of superabsorbent fibers, the superabsorbent fibers are arranged in homogenously in the whole layer, they intertwine with each other and are retained by the absorbent material, the superabsorbent fibers are able to absorb and retain juices or liquids emanating from the food product within the intermediate absorbent layer; the plastic layers physically retain the intermediate absorbent layer, either by means of a seal formed at least between two opposite lateral edges of said plastic layers or by using ultrasound or adhesive means; the plastic layers form a barrier between the food and the intermediate layer and prevent the return of liquids to the food. The absorbent pad of claim 1, wherein the upper and lower plastic layers are joined to each other, by two opposite side edges, by pressure, heat or adhesive means. The absorbent pad of claim 1, wherein the upper and lower plastic layers are joined together at all their side edges to form a peripheral seal, by pressure, heat or adhesive means. The absorbent pad of claim 1, wherein the absorbent materials of the intermediate layer are selected from: cotton fibers and their derivatives, cellulose fibers and their derivatives, as well as polyurethanes (sponges). The absorbent pad of claim 1, wherein the material constituting the superabsorbent fibers is selected from: acrylic acid polymer, acrylate polymer, isocyanate polymer and carboxymethyl cellulose. 6. The absorbent pad of claim 5, wherein the superabsorbent material forming the fiber is an acrylic acid polymer. The absorbent pad of claim 1, wherein the intermediate absorbent layer contains from 70 to 100% cellulose or other absorbent material and from 0 to 30% superabsorbent fiber. 8. The absorbent pad of claim 7, wherein the intermediate absorbent layer contains 2 to 30% superabsorbent fiber and the remainder is formed by absorbent material. The absorbent pad of claim 8, wherein the intermediate absorbent layer contains 10% superabsorbent fiber and 90% absorbent material. 10. The. The absorbent pad of claim 1, wherein the intermediate layer has a plurality of intersecting channels, formed by pressure and by heat, forming areas of high density of absorbent material and superabsorbent fibers and defining a plurality of cells of greater thickness than the channels. The absorbent pad of claim 10, wherein the channels in conjunction with the superabsorbent fibers and the absorbent material form highways that allow communication between cell and cell to feed all the cells, facilitating the distribution of the liquid throughout the layer intermediate absorbent. The absorbent pad of claim 1, wherein the material forming the upper and lower layers is a plastic material that is selected from: polyethylene, polypropylenes, PVC, polystyrenes and nonwoven polymers. The absorbent pad of claim 12, wherein the upper and lower plastic layers are made of polyethylene. 14. The absorbent pad of claim 3, wherein only one layer has perforations, the fabric or paper layer is adjacent to the perforated plastic layer and the non-perforated layer is adhered on its inner side to the absorbent intermediate layer. 15. The absorbent pad of claim 1, wherein the absorbent pad has the same shape as the bottom of the tray on which the food is placed and where the dimensions of the pad are equal to or slightly less than the bottom. of the tray. 16. The absorbent pad of claim 15, wherein the pad has a rectangular shape. 17. The absorbent pad of claim 1, wherein the pad is placed at the bottom of a tray for food product. 18. The absorbent pad of claim 3, wherein the two layers of plastic have perforations. 19. The absorbent pad of claim 2, wherein only one of the plastic layers is perforated, the fabric or paper layer is adjacent to the perforated plastic layer and the non-perforated layer is adhered to its inner face. to the absorbent intermediate layer. 20. The absorbent pad according to claims 14, 18, 19, 20, wherein the perforations have a cone-like shape, the tip of which is directed towards the intermediate layer of the pad. 25. The absorbent pad according to claims 14 and 19, wherein the perforated layer is the lower layer.