Absorbent food pad, its use and method for producing absorbent food pad

Abstract

An absorbent food pad, which comprises a monolayer of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres, and both surfaces of the monolayer of the nonwoven are treated with polysaccharide derivative. Further, the food pad comprises a layer of acrylate dispersion on both surfaces of the polysaccharide derivative treated monolayer of nonwoven.

Description

[0001] ABSORBENT FOOD PAD, ITS USE AND METHOD FOR PRODUCING

[0002] ABSORBENT FOOD PAD

[0003] Field of the invention

[0004] The present invention relates to an adsorbent food pad and its use. The invention relates also to a method for producing nonwoven absorbent food pad. of the invention

[0005] Absorbent food pads are commonly used in food packaging for improving on storage life and freshness of different food products, such as meat, poultry, fish and fruits. These products naturally contain liquids and occasionally these liquids will drain from the product with time. When such food products are packaged, these liquids may collect within the package. Absorbent food pad is a functional part of food packaging that is used to absorb superfluous liquid within the package.

[0006] Conventionally the food pads are laminated type food pads which are made of nonwoven material with polyethylene (PE) lamination in both sides of the nonwoven material. The aim of the PE film layers is to keep a surface of the food pad dry. However, solutions for food pads that are replacing PE- lamination are needed for sustainable transformation in food packaging industry.

[0007] Summary of the Invention

[0008] It is an object of the present invention is to provide a novel kind of absorbent food pad made of nonwoven material without polyethylene (PE) film outer layers.

[0009] An object of the present invention is to provide an absorbent food pad for use within a food package, such as in a food tray to absorb and withhold superfluous liquid. In order to achieve among others the objects presented above, the invention is characterized by what is presented in the characterizing parts of the enclosed independent claims.

[0010] Some preferred embodiments of the invention will be described in the other claims.

[0011] The embodiments and advantages mentioned in this text relate, where applicable, both to the absorbent food pad, the method as well as to the uses according to the invention, even though it is not always specifically mentioned.

[0012] Typical absorbent food pad according to the present invention comprises

[0013] - a monolayer of nonwoven, preferably a monolayer of airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres, and both surfaces of the monolayer of the nonwoven are treated with polysaccharide derivative, and

[0014] - a layer of acrylate dispersion applied on both surfaces of the polysaccharide derivative treated monolayer of nonwoven.

[0015] Typical method according to the present invention for producing nonwoven absorbent food pad comprises at least the following steps

[0016] - obtaining a monolayer web of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres,

[0017] - pre-treating the nonwoven monolayer web by applying polysaccharide derivative on both surfaces of the nonwoven monolayer web, and

[0018] - applying an aqueous acrylate dispersion on both surfaces of the pre-treated nonwoven monolayer web.

[0019] According to an embodiment of the present invention, an absorbent food pad is produced by the method according to the present invention.

[0020] Typically, an absorbent food pad according to the present invention is used as an absorbent material in a package, such as in a sealed food package or food tray. Food pad according to the present invention absorbs and withholds superfluous liquid within the package and thus helps to keep the food products fresh and improves the storage life of them.

[0021] The present invention is based on a simple method for producing food pad from nonwoven material without the PE film outer layers laminated in the surfaces of the nonwoven material. It has been observed that a monolayer of cellulose-based nonwoven, especially a monolayer of airlaid nonwoven with the multilayered structure of the binders according to the present invention provides a food pad with a rapid absorption rate of the liquids to the food pad and also good capability to withhold superfluous liquid in the food pad. In the present invention the binders, i.e. a polysaccharide derivative and an aqueous acrylate dispersion are applied on the back and top side of the nonwoven monolayer to provide the needed moisture and liquid management properties. Further, it has been observed that good strength properties are obtained by the surface treatments according to the present invention. The pre-treatment with polysaccharide derivate makes the surface of the fluffy and thick nonwoven smoother and thereby enabling application of a layer of an aqueous acrylate dispersion on the nonwoven surface so that the achieved layer is enough to manage moisture and also a delamination of the acrylate layer is prevented. Further, the binders used in the food pad according to the present invention are food contact approved and either fully or partially biobased or originated from renewable carbon sources. The present invention simplifies the production process and eliminates the need for plastic film layers, but however the present invention provides food pads comparable performance to PE-laminated commercial absorbent food pads.

[0022] Figure 1 illustrates a cross-section of an absorbent food pad according to an embodiment of the present invention.

[0023] Detailed description of the invention

[0024] According to the present invention, a food pad comprises a monolayer of nonwoven, preferably a monolayer of airlaid nonwoven. The monolayer refers to a single layer of nonwoven, preferably a single layer of airlaid nonwoven. In the present context, the term “nonwoven material” is understood as an engineered fibrous assembly, primarily planar, which has been given a designed level of structural integrity, i.e. a measurable level of tensile strength, and excluding materials obtained by weaving, knitting or paper making. The cellulose-based fibres, and optional other fibres, are engineered to a level of structural integrity primarily by physical and / or chemical means other than hydrogen bonding between the fibres. The term airlaid nonwoven refers to a manufacturing technology for producing a nonwoven web from short fibres. Typically, the airlaid nonwovens are produced from fluff pulp comprising softwood fibres, but also other natural and synthetic fibres can be used. The process is also referred to as short fibre airlaid technology. The airlaid process yields a nonwoven web that has loose, thick and soft construction. Hence, airlaid nonwoven provides good absorption properties for food pads.

[0025] According to the present invention, a monolayer of nonwoven, preferably a monolayer of airlaid nonwoven comprises at least 70 weight-% of cellulose- based fibres, calculated as dry from the total weight of the fibres. In an embodiment of the present invention a monolayer of nonwoven, preferably a monolayer of airlaid nonwoven comprises at least 80 weight-% of cellulose- based fibres, preferably 90 weight-% of cellulose-based fibres and more preferably 100 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres. According to one preferable embodiment the nonwoven material, such as airlaid nonwoven, consists of cellulose-based fibres. The cellulose-based fibres may comprise or be selected from natural cellulose fibres, man-made cellulosic fibres, i.e. man-made fibres of cellulosic origin, and any mixture thereof. According to an embodiment of the present invention natural cellulose-based fibres may be selected from wood fibres, such as softwood or hardwood fibres; seed hair fibres, such as cotton, kapok or milkweed fibres; leaf fibres, such as sisal, abaca or pineapple fibres; bast fibres, such as flax, hemp, jute or kenaf fibres; and any combinations thereof. The natural cellulose fibres may also comprise cellulosic fibres of microbiological origin. The natural cellulose-based fibres may have a fibre length in a range of 0.5 - 3.5 mm, preferably 1 - 3 mm.

[0026] The man-made cellulosic fibres may comprise regenerated cellulosic fibres, such as viscose fibres, lyocell fibres, modal fibres, acetate fibres, triacetate fibres, cupro fibres or any combinations thereof. The man-made cellulosic fibres may be or comprise Infinna™ fibres, loncell™ fibres, Spinnova™ fibres. The man-made cellulosic fibres are preferably staple fibres. The manmade cellulosic fibres may have a fibre length in a range of 3 - 15 mm, preferably 5 - 13 mm, more preferably 5 - 12 mm.

[0027] The cellulose-based fibres, both natural cellulose fibres and man-made cellulosic fibres may comprise virgin fibres or recycled fibres or a mixture of virgin fibres and recycled fibres.

[0028] In addition to the cellulose-based fibres, the monolayer may comprise other natural or synthetic fibres.

[0029] According to one embodiment of the invention, the nonwoven may comprise 70 - 100 weight-%, preferably 80 - 100 weight-%, more preferably 90 - 100 weight-% or 100%, calculated as dry, of natural cellulose fibres. In a preferred embodiment of the present invention natural cellulose-based fibres are softwood fibres. In an embodiment of the invention nonwoven is made of fluff pulp comprising softwood fibres. According to an embodiment of the present invention, a food pad comprises a monolayer structure where the nonwoven monolayer is made of 100 weight-% fluff pulp. Fluff pulp is commonly made of pulp comprising softwood fibres. Softwood pulp can be obtained from sulphate or sulphite pulping. The fluff pulp is hammer milled into individualized fibres, which are then air conveyed to a moving belt or forming wire to be formed into nonwoven. Natural cellulose fibres make the nonwoven material more sustainable and easier to deposit after the use. Furthermore, the natural cellulose fibres absorb moisture and water, and may thus provide the nonwoven material with advantageous absorption characteristics.

[0030] According to an embodiment of the present invention the nonwoven monolayer, preferably a monolayer of airlaid nonwoven has a basis weight of 100 - 200 g / m2, preferably 150 - 180 g / m2or 150 - 170 g / m2.

[0031] In a method according to the present invention, a dry monolayer of nonwoven web, preferably a dry monolayer of airlaid nonwoven web is firstly pretreated by applying a polysaccharide derivative on both surfaces of the nonwoven monolayer web for obtaining the pre-treated nonwoven monolayer web. Hence, a food pad according to the present invention comprises a monolayer of nonwoven, preferably airlaid nonwoven and both surfaces of the monolayer of the nonwoven are treated with polysaccharide derivative. According to the present invention, the pretreatment with a polysaccharide derivative smooths the surface of the thick and fluffy nonwoven, and also delamination and linting of the further acrylate layer is significantly reduced by applying a polysaccharide derivate on both surfaces of the nonwoven. Polysaccharide derivatives are also renewable and possibly even biodegradable materials, and their use can significantly reduce the environmental impact of produced food pad.

[0032] In an embodiment of the present invention polysaccharide derivative comprises alkyl celluloses, hydroxyalkyl alkyl celluloses, hydroxyalkyl celluloses, and any of their mixtures. Especially the polysaccharide derivative may be selected from C1-C4 alkyl celluloses, C1-C4 hydroxyalkyl celluloses, and any mixtures thereof. For example, the polysaccharide derivative may be selected from a group consisting of methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl cellulose, (hydroxyethyl)methyl cellulose, and (hydroxypropyl)methyl cellulose and any mixtures thereof. According to a preferred embodiment of the present invention polysaccharide derivative comprises or consisting of hydroxyethyl cellulose (HEC).

[0033] In an embodiment of the present invention the polysaccharide derivative has a number average molecular weight Mn in a range of 50 000 - 400 000 g / mol, preferably 70 000 - 120 000 g / mol, more preferably 80 000 - 100 000 g / mol.

[0034] Polysaccharide derivative is applied on the surfaces of the dry monolayer of nonwoven as an aqueous solution. In an embodiment of the present invention the polysaccharide derivative is applied on the surfaces of the nonwoven in an amount of 0.1 - 10 weight-%, preferably 0.5 - 5 weight-% or 0.5 - 2 weight-%, calculated from the dry weight of the fibres in the nonwoven web. It has been observed that a low addition of polysaccharide derivative is enough to lightly bond the further acrylate layer to the nonwoven core to prevent its delamination. After the pre-treatment with the polysaccharide derivative, an aqueous acrylate dispersion is applied on both surfaces of the pre-treated nonwoven monolayer web. Hence, a food pad according to the present invention comprises a layer of acrylate polymer on both surfaces of the polysaccharide derivative treated monolayer of nonwoven. Nonwoven monolayer web is preferably dried after the pretreatment with the polysaccharide derivate, wherein an aqueous acrylate dispersion is applied on a dry pretreated monolayer of nonwoven.

[0035] An aqueous acrylate dispersion according to the present invention is an aqueous acrylate polymer dispersion that is obtainable by a radical polymerisation, preferably by a free radical polymerisation, of one or more feeds of vinyl monomers. The vinyl monomers comprise at least one alkyl (meth)acrylate. The polymer dispersion may be obtained by radical polymerisation of one type of alkyl (meth)acrylate. Alternatively, the polymer dispersion may be obtained by a radical polymerisation of several, such as two, three or more, different vinyl monomers, of which at least one is alkyl (meth)acrylate. Preferably the polymer dispersion is obtained by a radical polymerisation of feed(s) of two or three different vinyl monomers of which at least one is alkyl (meth)acrylate. The different vinyl monomers may be fed as separate feeds, or one feed of vinyl monomers may comprise a mixture of two, three or more different vinyl monomers.

[0036] The vinyl monomers may comprise or consist of alkyl (meth)acrylates, which can be selected from as C1-C18 alkyl (meth)acrylates, preferably C1-C12 alkyl (meth)acrylates, more preferably C1-C4 alkyl (meth)acrylates, and any of their mixtures. Vinyl monomers may be selected from methyl acrylate; methyl methacrylate; ethyl acrylate; ethyl methacrylate; n-propyl or iso-propyl acrylate and corresponding propyl methacrylates; n-butyl, iso-butyl, tert-butyl or 2-butyl acrylate and the corresponding butyl methacrylates; n-pentyl or neopentyl acrylate and the corresponding pentyl methacrylates; 2-hexyl or 2- ethylhexyl acrylate and corresponding methacrylates; n-octyl or isooctyl acrylate and corresponding methacrylates; decyl acrylate; decyl methacrylate; dodecyl acrylate; dodecyl methacrylate; lauryl acrylate; lauryl methacrylate; stearyl acrylate; stearyl methacrylate. Preferably vinyl monomers may be selected from C1-C4-alkyl acrylates, C1-C4-alkyl methacrylates or any of their mixtures, e.g. n-butyl, iso-butyl, tert-butyl or 2- butyl acrylate and the corresponding butyl methacrylates; methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate or propyl methacrylate. It is possible that the vinyl monomers may comprise or consists of a mixture of at least two isomeric butyl acrylates, e.g. a mixture of n-butyl acrylate and methyl methacrylate or a mixture of n-butyl acrylate and tert-butyl acrylate.

[0037] According to an embodiment of the present invention the polymer dispersion is obtained by radical polymerisation of at least one feed of vinyl monomers, which comprise alkyl (meth)acrylates as listed above, in absence of styrene and substituted styrene monomers. The polymer dispersion according to the present invention is thus obtained without a monomer selected from styrene, substituted styrenes, such as a-methylstyrene, vinyltoluene, ethylvinyltoluene, chloromethylstyrene, and any of their mixtures. The obtained polymer dispersion is thus free of structural units originating from monomers selected from styrene, substituted styrenes, such as a- methylstyrene, vinyltoluene, ethylvinyltoluene, chloromethylstyrene, and any of their mixtures.

[0038] Typical aqueous acrylate dispersion according to the present invention comprises polymer particles dispersed in an aqueous continuous phase. The polymer dispersion may comprise polymer particles, which have a particle size D50 < 800 nm. The particle size D50 for the polymer particles of the dispersion may be, for example, in a range of 50 - 800 nm. Preferably 60 - 500 nm, more preferably 80 - 350 nm. Particle sizes are measured by using Zetasizer Nano ZS, Malvern. In the present context the particle size D50 refers to the value for 50th percentile of a volume-based distribution.

[0039] According to an embodiment of the invention, an acrylate polymer may have at least one glass transition temperature Tg in a range from -25 °C to +80 °C, more preferably from -20 °C to +40 °C, and even more preferably from -14 °C to +20 °C. The acrylate polymer may be also without clear glass transition temperature. The glass transition temperatures are measured from freeze dried samples using a differential scanning calorimeter Mettler Toledo DSC 3+. Dry solids content of an aqueous acrylate polymer dispersion applied on the surfaces of the pretreated monolayer of nonwoven material may be in the range of 5 - 50 weight-% of an acrylate polymer, calculated from the total weight of the aqueous dispersion. In an embodiment of the present invention the aqueous acrylate dispersion is applied on the surface of the pretreated nonwoven in an amount of 2 - 40 weight-%, preferably 10 - 40 weight-% or 10 - 35 weight-%, calculated from the dry weight of the pretreated nonwoven web.

[0040] In an embodiment of the present invention, a food pad comprises

[0041] - a monolayer of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres, and both surfaces of the monolayer of the nonwoven are treated with polysaccharide derivative, wherein the polysaccharide derivative is applied on the surface of the nonwoven in an amount of 0.1 - 10 weight-%, preferably 0.5 - 5 weight-% or 0.5 - 2 weight-%, calculated from the dry weight of the fibres in the nonwoven web, and

[0042] - a layer of acrylate dispersion applied on both surfaces of the polysaccharide derivative treated monolayer of nonwoven, wherein the aqueous acrylate dispersion is applied on the surface of the pretreated non-woven in an amount of 2 - 40 weight-%, preferably 10 - 40 weight-% or 10 - 35 weight-%, calculated from the dry weight of the pretreated nonwoven web.

[0043] A method according to an embodiment of the present invention for producing nonwoven adsorbent food pad comprises at least the following steps

[0044] - obtaining a monolayer web of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres,

[0045] - pre-treating the nonwoven monolayer web by applying polysaccharide derivative on both surfaces of the nonwoven monolayer web in an amount of 0.1 - 10 weight-%, preferably 0.5 - 5 weight-% or 0.5 - 2 weight-%, calculated from the dry weight of the fibres in the nonwoven web, and

[0046] - applying an aqueous acrylate dispersion on both surfaces of the pretreated nonwoven monolayer web, in an amount of 2 - 40 weight-%, preferably 10 - 40 weight-% or 10 - 35 weight-%, calculated from the dry weight of the pretreated nonwoven web. According to an embodiment of the present invention a polysaccharide derivative solution and an aqueous acrylate dispersion may be applied on the surfaces of the nonwoven web by any suitable application method. According to one embodiment of the invention they may be applied to by spraying, surface sizing, coating or by bath immersion. The application method may be chosen, for example, on basis of desired application amount or available operational equipment. In a preferred embodiment according to the present invention, a polysaccharide derivative solution and an aqueous acrylate dispersion are sprayed on the surfaces of the nonwoven web. According to a preferred embodiment of the present invention, a polysaccharide derivative solution is sprayed on both surfaces of the nonwoven web for obtaining the pretreated nonwoven web, and then the aqueous acrylate dispersion is sprayed on the top and the bottom of the pretreated nonwoven web, preferably on the surfaces of the pretreated nonwoven web which is dried after the pretreatment.

[0047] In an embodiment according to the present invention, a method may further comprise calendering the monolayer web of nonwoven prior to the pretreating by a polysaccharide derivative. Calendering smooths the surface of the nonwoven prior to the application of the polysaccharide derivative.

[0048] According to an embodiment of the present invention the nonwoven monolayer web is dried after applying aqueous acrylate dispersion on the web, e.g. at an elevated temperature.

[0049] After coating with the binders, food pads can be cut from the nonwoven web at the desired size.

[0050] Figure 1 shows a cross-section of the multilayered absorbent food pad according to an embodiment of the present invention. Food pad 1 comprises a monolayer of nonwoven 2. A polysaccharide derivative 3a, 3b, preferably a polysaccharide derivative comprising hydroxy ethylcellulose (HEC) is applied on both surfaces of the nonwoven monolayer 2 for forming polysaccharide derivate layers on both surfaces of the nonwoven monolayer 2. Polysaccharide derivative may exist, to some extent, throughout the nonwoven web, wherein it may not form a uniform layer of the polysaccharide derivative to the surface of the nonwoven monolayer, as illustrated in Figure 1. A layer of acrylate coating 4a, 4b is applied on both surface of the polysaccharide derivative treated nonwoven.

[0051] Some embodiments of the invention are described in the following nonlimiting examples.

[0052] EXPERIMENTAL

[0053] Preparation of Chemistries

[0054] Hydroxyethyl cellulose, HEC (Sigma Aldrich) was used as 0.38 weight-% solution, prepared by measuring cold deionized water into a beaker with a magnetic stirrer and gradually sprinkling the hydroxyethyl cellulose into a vortex under mixing for 1 .5 hours.

[0055] An aqueous acrylate dispersion was used as a binder. Aqueous acrylate dispersion according to the present invention was dispersion of poly(meth)acrylate comprising 2-ethylhexyl acrylate and methyl methacrylate having Tg +16 °C.

[0056] Manufacture of Nonwoven Material

[0057] An air-laid nonwoven material web was manufactured by using pilot airlaying unit (Dan-Web, Denmark) equipment and commercial fluff pulp (Golden isles fluff pulp, GP Cellulose), average fibre length of2 mm. The air-laid nonwoven material web was calendered at 70 °C, speed 1 m / min, gap 0.00 mm, for reduced loftiness and delamination. The grammage of the nonwoven web was 160 g / m2.

[0058] The hydroxyethyl cellulose solution was applied first to the formed nonwoven as 1 weight-% of dry fibre in nonwoven with a gravity feed hand spray gun, which was connected to an air line with pressure at 0.5 bar. The nonwoven web was sprayed on both sides and dried in an oven at 120 °C for 8 min after each spray. The aqueous acrylate dispersion used as a binder was applied in desired amount with the above-mentioned hand spray gun and dried in an oven. The nonwoven material web was sprayed with the binder on both sides and dried in the oven at 105 °C for 3 min after each spray.

[0059] The chemistry compositions and applied amounts are given in Table 1. Reference material was a commercial PE covered food pad. PE film layer was approximately 33 pm thick and approximately 20 g / m2. The thick of the whole reference material was 0.88 mm.

[0060] Testing of Nonwoven Material

[0061] Nonwoven materials, prepared above, were conditioned in 23 °C, 50 % relative humidity for 20 minutes before testing.

[0062] The following properties were tested from the samples of nonwoven material by using Nonwovens Standard Procedures (NWSP):

[0063] - Dry tensile strength: EDANA - NWSP 1104R0 (20), five parallel measurements.

[0064] - Liquid absorptive capacity (LAC): EDANA - NWSP 0101 R0 (20), five parallel measurements.

[0065] Strikethrough and rewet tests are typically used in hygiene products, and they were adapted for this application. Strikethrough test assesses the speed at which material absorbs liquids, measures the time it takes for liquid to penetrate through the fabric. A shorter time implies a better result, showing that material facilitates rapid absorption and distribution of liquids. A Gester Strikethrough tester was used for measuring strikethrough. The testing procedure for strikethrough was adapted from the nonwoven standard procedure NWSP 070.3.R1 (19). The main modification was using 6 mL of saline solution instead of 5mL.

[0066] Rewet test evaluates the non-woven absorbent food pad’s capacity to retain liquid without releasing it back onto its surface. It measures the amount of liquid released at the surface of the material after placing a weight on the food pad. A low rewet value is desired as it prevents accumulation of liquids and growth of bacteria. The rewet test was adapted from the nonwoven standard procedures NWSP 070.9. R1 (15) and NWSP 080.10.R2(2O), where the rewet part of the test was carried out immediately after the strikethrough test.

[0067] Results of Produced Nonwoven Material

[0068] Table 2. Characteristics of manufactured nonwoven materials.

[0069] Based on the test results, it was found out that the pre-treatment of the nonwoven surfaces with polysaccharide derivative, such as hydroxyethyl cellulose (HEC) was required to prevent linting and delamination of the acrylate binder layer. In sample 4 it was seen that 20 % add-on of the acrylate dispersion in combination with the pre-treatment produced a nonwoven food pad product that had the best strikethrough and rewet, and a second-best LAC of the test series. The sample also exhibited good dry tensile results, which made it comparable to the commercial reference product with PE-lamination. The present invention thus provides an alternative way to produce food pads from nonwoven materials, without compromising its performance properties.

Claims

Claims1 . An absorbent food pad, characterized in that it comprises- a monolayer of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres, and both surfaces of the monolayer of the nonwoven are treated with polysaccharide derivative, and- a layer of acrylate dispersion applied on both surfaces of the polysaccharide derivative treated monolayer of nonwoven.

2. The absorbent food pad according to claim 1 , characterized in that the nonwoven comprises at least 80 weight-% of cellulose-based fibres, preferably 90 weight-% of cellulose-based fibres and more preferably 100 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres.

3. The absorbent food pad according to claim 1 or 2, characterized in that cellulose-based fibres comprise natural cellulose fibres, man-made cellulosic fibres, and any mixture thereof.

4. The absorbent food pad according to any one of the preceding claims, characterized in that the nonwoven, preferably airlaid nonwoven has a basis weight of 100 - 200 g / m2, preferably 150 - 180 g / m2or 150 - 170 g / m2.

5. The absorbent food pad according to any one of the preceding claims, characterized in that the polysaccharide derivative comprises alkyl celluloses, hydroxyalkyl alkyl celluloses, hydroxyalkyl celluloses, and any of their mixtures.

6. The absorbent food pad according to claim 5, characterized in that the polysaccharide derivative is selected from a group consisting of methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl cellulose, (hydroxyethyl)methyl cellulose, and (hydroxypropyl)methyl cellulose and any mixtures thereof, preferably hydroxyethyl cellulose.

7. The absorbent food pad according to any one of the preceding claims, characterized in that the polysaccharide derivative has a number average molecular weight Mn in a range of 50 000 - 400 000 g / mol, preferably 70 000- 120 000 g / mol, more preferably 80 000 - 100 000 g / mol.

8. The absorbent food pad according to any one of the preceding claims, characterized in that the aqueous acrylate dispersion is obtained by a radical polymerisation of one or more feeds of vinyl monomers, wherein the vinyl monomers comprise at least one alkyl (meth)acrylate.

9. Method for producing nonwoven absorbent food pad,- obtaining a monolayer web of nonwoven, preferably airlaid nonwoven comprising at least 70 weight-% of cellulose-based fibres, calculated as dry from the total weight of the fibres,- pre-treating the nonwoven monolayer web by applying polysaccharide derivative on both surfaces of the nonwoven monolayer web, and- applying an aqueous acrylate dispersion on both surfaces of the pretreated nonwoven monolayer web.

10. The method according to claim 9, characterized in that the polysaccharide derivative comprises alkyl celluloses, hydroxyalkyl alkyl celluloses, hydroxyalkyl celluloses, and any of their mixtures.

11. The method according to claim 9 or 10, characterized in that the polysaccharide derivative is selected from a group consisting of methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl cellulose, (hydroxyethyl)methyl cellulose, and (hydroxypropyl)methyl cellulose and any mixtures thereof, preferably hydroxyethyl cellulose.

12. The method according to any one of the preceding claims 9-11 , characterized in that the polysaccharide derivative is applied on the surface of the nonwoven web in an amount of 0.1 - 10 weight-%, preferably 0.5 - 5 weight-% or 0.5 - 2 weight-%, calculated from the dry weight of the fibres in the nonwoven web.

13. The method according to any one of the preceding claims 9-12, characterized in that the monolayer web of nonwoven is calandered prior to the pre-treating with polysaccharide derivative.

14. The method according to any one of the preceding claims 9-13, characterized in that the aqueous acrylate dispersion is applied on the surface of the pretreated nonwoven web in an amount of 2 - 40 weight-%, preferably 10 - 40 weight-% or 10 - 35 weight-%, calculated from the dry weight of the pretreated nonwoven web.

15. Use of absorbent food pad according to any of the preceding claims 1-8 as an absorbent material in a package.

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