Antimicrobial nonwoven product

Abstract

The invention relates to an antimicrobial nonwoven fabric product comprising or consisting of cellulose functionalized with silver and ruthenium as well as regenerated fibers.

Description

[0001] The present invention relates to a novel antimicrobial nonwoven fabric product, a method for its production, and the use of the antimicrobial nonwoven fabric product for antimicrobial cleaning.

[0002] Several antimicrobial textile products are already known from the prior art. For example, DE 10 2006 056977 B3 describes a bacteriostatic effect achieved through the use of a textile microbicidal reservoir. This reservoir is formed from fibers consisting of a solid composite of ion-exchange particles loaded with silver ions and a cellulose matrix. However, a disadvantage is that the silver ions are washable out over time, and consequently, the desired effect is lost.

[0003] The process of imparting antimicrobial properties to cellulose fibers by coating them with biocidal silver nanoparticles is described, for example, in US 8,367,089 B2. However, this method also suffers from the problem of the active ingredient leaching out over time, leading to a loss of antimicrobial properties.

[0004] A process for producing an antimicrobial fiber material that prevents the leaching of active ingredients and maintains antimicrobial efficacy even after numerous washes is disclosed in EP 4 187 004 A1. This patent describes so-called "hygiene fibers" comprising a cellulose fiber material and metallic silver and metallic ruthenium as active ingredient components. The silver and ruthenium are in electrical contact and, due to their different electrochemical potentials, form a galvanic cell. The redox reactions occurring at the electrodes of this galvanic cell generate oxygen radicals that are toxic to microorganisms. Furthermore, the microorganisms are also destroyed oxidatively by the release of electrons to the silver semiconductor.

[0005] This fiber material is produced by mixing cellulose pulp with at least one solvent and water. The cellulose or cellulose derivatives contained in the cellulose are dissolved in the pulp to create a spinning solution. Metallic silver and metallic ruthenium are added to the pulp, the spinning solution, or the solvent. After obtaining the spinning solution, it is extruded through spinnerets, and the cellulose or cellulose derivatives are then regenerated to produce modified cellulose and / or cellulose derivative fibers, also known as AgXX fibers. The active ingredients, silver and ruthenium, are completely embedded in the fibers and / or at least partially surrounded by them. Nonwovens can be produced from the modified fibers obtained in this way using standard textile fabrication processes.

[0006] A disadvantage of nonwovens containing antimicrobial fibers produced in this way is the very high energy consumption and associated high manufacturing costs. The production of the fibers modified with the active ingredient is already very complex, and this is followed by an equally complex process of bonding them into a nonwoven fabric, which is usually multi-layered and then requires further bonding with additional layers in a subsequent process step.

[0007] Furthermore, cloths made of CAC (carded / airlaid / carded) material are known from the prior art. CAC material is a composite material consisting of two carded viscose outer layers and a cellulose middle layer, bonded together by water jet bonding. The CAC material known from the prior art has a basis weight of up to 80 g / m². 2and is known for uses that do not require high tear resistance or high storage capacity for impregnating agents, for example for baby cleaning and care, makeup removal or personal hygiene products.

[0008] JP 2020-20075 A describes a wet wipe containing cellulose fibers that have a metal component selected from silver, gold, platinum, palladium, copper and zinc.

[0009] JP 2004-323980 A describes a sweat-absorbing element intended to have antibacterial properties and minimize unpleasant odors. The sweat-absorbing element comprises a water-absorbing layer made of a metal-containing fiber with antibacterial properties. The metal is preferably copper, zinc, or silver. Object of the invention

[0010] The object of the present invention is to provide an alternative antimicrobial nonwoven product and a method for its production which overcome the aforementioned disadvantages known from the prior art and are characterized in particular by the fact that the nonwoven product can be produced in a process-economical manner. General description of the invention

[0011] The invention solves this problem with the features of the claims and in particular with an antimicrobial nonwoven fabric product comprising or consisting of cellulose functionalized with silver and ruthenium as well as regenerated fibers.

[0012] The term "pulp" refers to a cellulose pulp containing loose cellulose fibers.

[0013] "Silver and ruthenium functionalized pulp" refers to pulp in which the fibers contained therein are modified with silver and ruthenium, i.e., in which silver and ruthenium are chemically or physically bonded to the cellulose fibers.

[0014] Within the scope of the present invention, it has been found that it is not necessary to first solidify silver- and ruthenium-functionalized cellulose into a nonwoven fabric before combining it with one or more other nonwovens, particularly those containing regenerated fibers, by a suitable process to form a multilayer nonwoven fabric product. Instead, it is possible to directly mix the loose cellulose fibers of the functionalized cellulose with regenerated fibers, in particular to mix them homogeneously, and to solidify this mixture directly into a nonwoven fabric by hydroentanglement. In this way, the cellulose is embedded between the regenerated fibers in the resulting nonwoven fabric. Preferably, the weight fraction of the silver- and ruthenium-functionalized cellulose is 1.0–85.0 wt.-%, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of regenerated fibers is preferably 15.0 - 99.0 wt.%, based on the total weight of the antimicrobial nonwoven product.

[0015] Alternatively, it is also possible to arrange the cellulose functionalized with silver and ruthenium in a first layer and to bond this layer to a second layer, preferably a nonwoven fabric made of bonded regenerated fibers, by means of water jet bonding. In this embodiment, the antimicrobial nonwoven fabric product according to the invention has a first layer with or made of cellulose functionalized with silver and ruthenium, and a second layer bonded to this first layer, which comprises or consists of regenerated fibers.

[0016] The term "regenerated fibers" refers to fibers produced from naturally occurring, renewable raw materials through chemical processes. Preferred regenerated fibers contained in the second layer are viscose fibers, lyocell fibers, and / or cotton fibers. In particular, the regenerated fibers are carded; that is, the second layer preferably consists of carded viscose, carded lyocell, and / or carded cotton.

[0017] In one embodiment, the antimicrobial nonwoven product according to the invention consists of two interconnected layers, namely the first layer, which comprises or consists of cellulose functionalized with silver and ruthenium, and the second layer, which comprises or consists of regenerated fibers, wherein both layers are preferably interconnected by water jet bonding. In this embodiment, the weight fraction of the first layer is preferably 1.0–85.0 wt.%, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of the second layer is preferably 15.0–99.0 wt.%, based on the total weight of the antimicrobial nonwoven product.

[0018] According to a further embodiment, the antimicrobial nonwoven fabric product according to the invention comprises three layers, namely a first layer comprising or consisting of cellulose functionalized with silver and ruthenium, a second layer comprising or consisting of regenerated fibers, and a third layer, which optionally consists of the same material as the second layer, i.e., preferably also of carded viscose, carded lyocell, and / or carded cotton, wherein the three layers are preferably bonded together by water jet bonding. The third layer is arranged on the side of the first layer facing away from the second layer, so that the first layer with the cellulose functionalized with silver and ruthenium is sandwiched between the second and third layers.

[0019] In the aforementioned embodiment, in which the second and third layers consist of the same material, and this material is carded viscose, the antimicrobial nonwoven fabric product according to the invention is structurally similar to the CAC material already known from the prior art. This is a three-layer material in which an airlaid cellulose layer is arranged between two carded viscose outer layers. However, instead of the middle airlaid cellulose layer, the nonwoven fabric product according to the invention has cellulose functionalized with silver and ruthenium. It was surprisingly found that the antimicrobial effect of this functionalized cellulose is maintained even in multi-layered nonwoven fabric products, even when the layer containing the active ingredient is surrounded on both sides by other material.However, even when the functionalized cellulose is distributed between the regenerated fibers, the antimicrobial effect of the functionalized cellulose is retained.

[0020] In the three-layer embodiment of the antimicrobial nonwoven product according to the invention, in which the second and third layers comprise or consist of regenerated fibers, the weight fraction of the first layer is preferably 1.0 - 85.0 wt. %, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of the second and third layers is preferably 7.5 - 49.5 wt. %, each based on the total weight of the antimicrobial nonwoven product.

[0021] In an alternative three-layer embodiment, the antimicrobial nonwoven fabric product according to the invention comprises three layers: a first layer comprising or consisting of cellulose functionalized with silver and ruthenium, a second layer comprising or consisting of regenerated fibers, and a third layer comprising or consisting of thermally bonded plastic fibers, wherein the plastic fibers are thermoplastic plastic fibers preferably selected from the group consisting of polypropylene fibers, polyethylene terephthalate fibers, polylactic acid fibers, polybutylene succinate fibers, polyhydroxyalkanoate fibers, and mixtures thereof. In this embodiment, the third layer is in particular a spunbond layer, i.e., a nonwoven fabric made of plastic fibers spun from polymer melts passing through nozzles and drawn by means of cold air and / or mechanically.Furthermore, in this embodiment, the weight fraction of the first layer is preferably 1.0 - 85.0 wt. %, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of the second and third layers is preferably 7.5 - 49.5 wt. %, each based on the total weight of the antimicrobial nonwoven product.

[0022] The antimicrobial nonwoven product according to the invention is preferably a dry nonwoven product, but one that is suitable for absorbing an impregnating agent, e.g., water. This impregnating agent is preferably applied to the nonwoven product by the user before use, or the nonwoven product is impregnated with it. Alternatively, the antimicrobial nonwoven product according to the invention can already be pre-impregnated with an impregnating agent and packaged, so that the user only needs to remove it from the packaging and can use it directly.

[0023] Regardless of whether the nonwoven fabric product according to the invention is already pre-impregnated with an impregnating agent or is only impregnated with an impregnating agent by the user, the impregnating agent optionally contains, in addition to water, at least one compound with antimicrobial properties, oil, preservative, surfactant, emulsifier, skin-conditioning ingredient, moisturizing ingredient and any combination thereof.

[0024] Regardless of the number and composition of the layers of the nonwoven fabric product according to the invention, the layers of which it consists are preferably solidified or bonded together by water jet bonding and without binders.

[0025] Optionally, the antimicrobial nonwoven product according to the invention can have or be connected to fastening means, e.g., straps, buttons, hooks, a zipper, or, in particular, a hook-and-loop fastener, wherein the antimicrobial nonwoven product can be attached to a wiping device by means of the aforementioned fastening means. Alternatively, the antimicrobial nonwoven product according to the invention can not itself have these fastening means, but rather engage with them, for example, by attaching a hook-and-loop fastener arranged on a wiping device to the antimicrobial nonwoven product, or by engaging a hook or button arranged on a wiping device in an eyelet arranged on the antimicrobial nonwoven product.

[0026] The invention further relates to a method for producing an antimicrobial nonwoven fabric product, comprising the consolidation of cellulose functionalized with silver and ruthenium as well as of regenerated fibers by means of water jet consolidation.

[0027] Preferably, the weight fraction of the provided functionalized cellulose is 1.0 - 85.0 wt.%, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of the provided regenerated fibers is preferably 15.0 - 99.0 wt.%, based on the total weight of the antimicrobial nonwoven product.

[0028] To produce a multilayer antimicrobial nonwoven fabric product, the inventive method according to one embodiment comprises providing a first layer containing the cellulose functionalized with silver and ruthenium, providing a second layer containing the regenerated fibers, and optionally providing a third layer made of the same or different material as the second layer, wherein the layers are joined by means of water jet bonding, and wherein optionally the third layer is joined to the first layer on the side of the first layer facing away from the second layer.

[0029] The third layer provided in the inventive process optionally consists of the same material as the second layer and preferably of carded viscose, carded lyocell and / or carded cotton. Since the third layer is arranged on the side of the first layer facing away from the second layer, the first layer, containing the cellulose functionalized with silver and ruthenium, is sandwiched between the second and third layers.

[0030] Preferably, the weight fraction of the first layer provided in the inventive process for the production of a three-layer nonwoven product is 1.0 - 85.0 wt.%, based on the total weight of the antimicrobial nonwoven product, and the weight fraction of the provided second and third layers is preferably 7.5 - 49.5 wt.%, each based on the total weight of the antimicrobial nonwoven product.

[0031] In one embodiment of the method according to the invention, thermally bonded plastic fibers are provided as a third layer, wherein the plastic fibers are thermoplastic plastic fibers, preferably selected from the group consisting of polypropylene fibers, polyethylene terephthalate fibers, polylactic acid fibers, polybutylene succinate fibers, polyhydroxyalkanoate fibers and mixtures thereof.

[0032] Preferably, to produce a three-layer nonwoven fabric product, a first layer containing the functionalized and unconsolidated cellulose, a second layer containing pre-consolidated, in particular carded, regenerated fibers, and a third layer containing either also pre-consolidated, in particular carded, regenerated fibers or thermally bonded plastic fibers are arranged on top of each other, such that the first layer is located between the second and the third layer.

[0033] In the context of the present invention, “solidified” or “pre-solidified” means that the fibers contained in the layer are not loose, but are already bonded together by a treatment or process.

[0034] In the process according to the invention, for the production of a nonwoven fabric product that does not comprise several layers, the regenerated fibers, which are preferably in a homogeneous mixture with the cellulose functionalized with silver and ruthenium, are fed to a device for generating water jets and solidified by means of water jet bonding.

[0035] Similarly, to produce a multi-layered nonwoven fabric product, the layers arranged on top of each other are fed into a device for generating water jets, in which the layers are joined together by water jet bonding.

[0036] In the aforementioned embodiment, since the first layer, comprising the functionalized cellulose, is bonded to the at least one, and preferably two, adjacent layer(s) by water jet bonding to form the antimicrobial nonwoven product, an additional intermediate layer in which the functionalized cellulose is first pre-bonded is avoided. As a result, the production of a multi-layered antimicrobial nonwoven product requires less energy than a process in which the functionalized cellulose is first pre-bonded by a suitable method and then bonded to the adjacent layer(s), making the process according to the invention more resource-efficient and cost-effective.Surprisingly, it was also found that the antimicrobial effect of a nonwoven fabric product produced by a method according to the invention is comparable to the effect of a pre-solidified fiber material containing the functionalized fibers.

[0037] Accordingly, the present invention also relates to the use of an antimicrobial nonwoven fabric product according to the invention for antimicrobial cleaning, for example of living and / or non-living surfaces.

[0038] The features of the invention disclosed in the foregoing description and in the claims can be essential for the realization of the invention in its various embodiments, both individually and in any combination.

Claims

[1] Antimicrobial nonwoven wipe product, characterized by that this includes or consists of cellulose functionalized with silver and ruthenium as well as regenerated fibers. [2] Antimicrobial nonwoven wipe product according to claim 1, characterized by , that the cellulose functionalized with silver and ruthenium is contained in a first layer which is connected to a second layer which comprises or consists of the regenerated fibers. [3] Antimicrobial nonwoven wipe product according to claim 2, characterized by a third layer connected to the first layer, wherein the third layer is arranged on the side of the first layer facing away from the second layer and optionally consists of the same material as the second layer. [4] Antimicrobial nonwoven product according to any one of the preceding claims, characterized by that it is solidified by water jet compaction and without the use of binders. [5] Antimicrobial nonwoven wipe product according to claim 1, characterized by , that the cellulose functionalized with silver and ruthenium and the regenerated fibers are mixed together, so that the cellulose is distributed between the regenerated fibers. [6] Antimicrobial nonwoven product according to claim 3 or 4, characterized by , that the third layer is not made of the same material as the second layer, but comprises or consists of thermally bonded plastic fibers, wherein the plastic fibers are thermoplastic plastic fibers, preferably selected from the group consisting of polypropylene fibers, polyethylene terephthalate fibers, polylactic acid fibers, polybutylene succinate fibers, polyhydroxyalkanoate fibers and mixtures thereof. [7] Antimicrobial nonwoven product according to any one of the preceding claims, characterized by, that the weight fraction of the cellulose functionalized with silver and ruthenium is 1.0 - 85.0 wt.%, based on the total weight of the antimicrobial nonwoven product. [8] Method for producing an antimicrobial nonwoven fabric product comprising the consolidation of cellulose functionalized with silver and ruthenium and of regenerated fibers by water jet consolidation. [9] Method according to claim 8, characterized byProviding a first layer containing the cellulose functionalized with silver and ruthenium, providing a second layer containing the regenerated fibers, and optionally providing a third layer consisting of the same or different material as the second layer, wherein the layers are joined by water jet bonding, and wherein optionally the third layer is joined to the first layer on the side of the first layer facing away from the second layer. [10] Use of an antimicrobial nonwoven wipe product according to any one of claims 1 to 7 for antimicrobial cleaning.