Wet wipe for surface disinfection
Patent Information
- Application Number
- EP2023786189
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-10-18
- Filing Date
- 2023-09-27
- Publication Date
- 2025-08-27
AI Technical Summary
Existing disposable wet wipes for surface disinfection face challenges such as high environmental impact due to non-biodegradable materials, ineffective antimicrobial agents, and reduced effectiveness when used with biodegradable nonwovens, which fail to achieve virucidal activity against adenovirus within the required time.
A disposable wet wipe featuring a biodegradable nonwoven fabric with fibers longer than 5 mm, soaked with an impregnating agent containing 35-80% C1-C4 alcohol, an amino alcohol, a surfactant, and water, maintaining a pH between 8 and 12, and free of phosphonates, which stabilizes the alkaline pH and achieves rapid virucidal activity against adenovirus.
The solution provides high environmental compatibility and excellent virucidal efficacy against adenovirus within 3 minutes, exceeding the DIN EN 14476 requirements, even at low impregnation levels, while maintaining stability and effectiveness with biodegradable nonwovens.
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Abstract
Description
[0001] Wet wipes for surface disinfection
[0002] It is well known that germs of all kinds thrive on surfaces, especially in warm and / or humid environments. Therefore, regular cleaning and / or disinfection of these surfaces is essential in both public and private areas to thoroughly remove dirt and germs and ensure the cleanliness of the respective surface. This is of course particularly important in places such as schools, swimming pools, restaurants and cultural institutions where large numbers of people regularly gather, as well as in places such as hospitals and doctor's offices where sick people and those with weakened immune systems are found. But regular and effective cleaning of surfaces is also necessary in private areas, especially in bathrooms and kitchens, to effectively remove germs and prevent their spread.
[0003] To clean or disinfect surfaces, a cleaning agent or disinfectant is often applied to a nonwoven fabric, which is then used for cleaning. The nonwoven fabric is then washed after cleaning. This needs improvement in several respects. Firstly, it is possible that the nonwoven fabric is forgotten to be washed thoroughly and instead is simply rinsed under running water, which allows germs to remain on the surface and spread. Even if the fabric is not washed immediately, the germs on the surface of the nonwoven fabric spread if it is stored in the washing machine until the next wash cycle is started. In this way, the nonwoven fabric actually intended for cleaning actually represents a risk of spread contamination or a source of contamination.
[0004] This problem is addressed in the prior art by providing disposable wet wipes intended for cleaning or disinfecting surfaces and therefore pre-soaked with an antimicrobial impregnating agent. A disadvantage of such disposable wipes is their high environmental impact, since the nonwoven fabric impregnated with an impregnating agent in most conventional disposable wipes is not biodegradable but a plastic nonwoven, for example, made of PET.
[0005] In the case of biodegradable nonwovens impregnated with an impregnating agent for the production of disposable wipes, it was observed that the originally alkaline pH of the impregnating agent is shifted to the acidic range upon application of the impregnating agent to the nonwoven, thereby causing a significant loss of the impregnating agent's effectiveness. This is apparently due to residues from the manufacturing process in the biodegradable nonwovens, which are produced, for example, using sulfuric acid.
[0006] A state-of-the-art product without a synthetic fleece, whose impregnating agent has a pH value of 3-3.6, is known, for example, under the trade name "mikrozid® universal wipes green line." However, this product does not achieve the required effectiveness against adenovirus according to DIN EN 14476 after less than 5 minutes, but only achieves the corresponding effectiveness after 15 minutes.
[0007] AU 2003259326 B2 describes an aqueous cleaning and disinfection solution for hard surfaces with a pH of 1.0-3.0, an ethanol content of 0.1-10 wt.%, and an acid as well as an anionic and a non-ionic surfactant. This product also fails to achieve the required effectiveness against adenovirus according to DIN EN 14476 after less than 5 minutes.
[0008] Furthermore, EP 2 898 775 B1 discloses applying an alcoholic impregnating agent containing 45-65 wt.% alcohol and phosphonates to a nonwoven fabric, which may also be biodegradable. Phosphonates are known to be difficult to degrade and can also be ecotoxic. Furthermore, they leave undesirable residues on the treated surfaces.
[0009] DE 10 2020 134 229 A1 describes cleaning wipes impregnated with dishwashing detergent, which may contain a nonwoven textile material with fibers from natural sources such as viscose and cellulose. The impregnating agent can optionally be phosphonate-free and also contain a disinfectant. However, the impregnated wipe is not suitable for surface disinfection because the alcohol content of the impregnating agent is only 10% by weight maximum. Furthermore, the impregnating agent has a high viscosity, typical of dishwashing detergents, and is therefore also unsuitable for surface disinfection.
[0010] Object of the invention
[0011] It is the object of the present invention to provide an alternative disposable wet wipe for surface disinfection which overcomes the aforementioned disadvantages known from the prior art and is characterized in particular by high environmental compatibility and by excellent virucidal properties of the impregnating agent it contains.
[0012] General description of the invention
[0013] The invention solves this problem with the features of the claims and in particular with a disposable wet wipe for surface disinfection, which comprises a biodegradable nonwoven fabric made of fibers with a fiber length > 5 mm, which is impregnated with an impregnating agent containing 35-80 wt.% alcohol, wherein the alcohol is a C1-C4 alcohol or a mixture of C1-C4 alcohols, and wherein the impregnating agent further contains an amino alcohol, a surfactant and water and has a pH in the range of pH 8 to pH 12.
[0014] The impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated is preferably phosphonate-free and preferably also contains no other phosphorus compounds. For the purposes of the present invention, a wet wipe is understood to mean a disposable wet wipe comprising a nonwoven fabric impregnated with an impregnating agent. The terms "wet wipe" and "disposable wet wipe" are used synonymously in the present disclosure.
[0015] It was surprisingly found that the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated can stabilize an alkaline pH even when applied to a biodegradable nonwoven fabric made of fibers with a fiber length of > 5 mm, in particular fibers with a fiber length of > 8 mm, e.g., a nonwoven fabric made of viscose and / or lyocell. This is remarkable because impregnating agents on biodegradable nonwoven fabrics generally tend to shift the pH into the acidic range.
[0016] The fact that stabilization of an alkaline pH value is possible with the wet wipe according to the invention is attributed to the fact that the impregnating agent contained in the wet wipe according to the invention contains an amino alcohol, which has a stabilizing effect on the pH value and apparently has a synergistic effect with the biodegradable nonwoven fabric made of fibers with a fiber length > 5 mm.
[0017] The amino alcohol contained in the impregnating agent is preferably an amino alcohol selected from the group consisting of monoethanolamine, aminomethyl propanol (AMP, 2-amino-2-methylpropanol), monoisopropanolamine (MIPA, 1-aminopropan-2-ol), tetrahydroxypropylethylenediamine, and combinations thereof. Further preferably, the total proportion of one or more of the aforementioned amino alcohols in the impregnating agent is 0.02-5.0 wt.%, more preferably 0.04-3.5 wt.%, even more preferably 0.06-2.0 wt.%, and most preferably 0.08-0.5 wt.%.
[0018] The impregnating agent has a pH value in the range of 8 to 12 both before application to the nonwoven fabric and after application to the nonwoven fabric, i.e., in the wet wipe according to the invention, in which it impregnates the nonwoven fabric made of viscose and / or lyocell. The pH value of the impregnating agent is preferably in the range of 8.5 to 11 and particularly preferably in the range of 9 to 10.
[0019] In addition to the amino alcohol, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated optionally contains one or more organic acids as pH-regulating ingredients, for example citric acid, e.g., in the form of the monohydrate. Organic acids can be present in the impregnating agent at 0.02-5.0 wt%, more preferably at 0.04-3.5 wt%, even more preferably at 0.06-2.0 wt%, and most preferably at 0.08-0.5 wt%.
[0020] According to the invention, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated contains 35-80 wt.% alcohol, wherein the alcohol is a C1-C4 alcohol, i.e., an alcohol with 1 to 4 carbon atoms, or a mixture of C1-C4 alcohols. The alcohol is preferably selected from the group consisting of methanol, ethanol, propanol, isopropanol, butanol, isobutanol, and mixtures thereof.
[0021] The proportion of alcohol in the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated is preferably 40-60 wt% and particularly preferably 45-55 wt%.
[0022] Furthermore, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated contains at least one surfactant, which can in particular be a C8-C10 alkyl polyglycoside. The surfactant is preferably present in the impregnating agent in an amount of 0.05-5.0 wt.%, more preferably in an amount of 0.2-3.5 wt.%, even more preferably in an amount of 0.35-2.0 wt.%, and most preferably in an amount of 0.5-1.0 wt.%.
[0023] In addition, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated also contains water.
[0024] According to a preferred embodiment, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated contains alcohol, which is preferably ethanol, a surfactant, an amino alcohol, which is preferably monoethanolamine, aminomethyl propanol, monoisopropanolamine and / or tetrahydroxypropylethylenediamine, and water or consists of these components.
[0025] Optionally, however, the impregnating agent may also contain other ingredients found in conventional impregnating agents, in particular oil, preservatives, emulsifiers, skin care ingredients, moisturizing ingredients and any combination thereof.
[0026] The nonwoven fabric contained in the wet wipe according to the invention is a biodegradable nonwoven fabric made of fibers with a fiber length > 5 mm, in particular a biodegradable nonwoven fabric made of fibers with a fiber length > 8 mm and particularly preferably a biodegradable nonwoven fabric made of viscose and / or lyocell.
[0027] In the context of the present disclosure, “biodegradable” means that the nonwoven fabric comprising the wet wipe according to the invention decomposes into its elemental components in the environment or is decomposed into these components by microorganisms, the time required for this being irrelevant.
[0028] Preferably, the impregnating agent with which the nonwoven fabric in the wet wipe according to the invention is impregnated has a virucidal effect according to DIN EN 14476. According to this standard, the impregnating agent must be effective against the adenovirus within less than 5 minutes, with the effectiveness being expressed in a reduction of the germ load by more than 4 log levels.
[0029] The impregnating agent according to the invention preferably achieves the aforementioned effectiveness after only 3 minutes, which is extremely remarkable, since the effectiveness of wet wipes containing a biodegradable nonwoven impregnated with an impregnating agent against adenovirus has not been achieved in the prior art. Rather, wet wipes based on biodegradable nonwovens known from the prior art showed a general decrease in the effectiveness of the impregnating agents when applied to the nonwoven.
[0030] During experiments leading to the present invention, it was also observed that the effectiveness of the impregnating agent decreased when biodegradable nonwovens that did not consist of fibers with a fiber length of > 5 mm were used. Furthermore, it was observed that impregnating agents that did not contain amino alcohol did not exhibit the desired effectiveness against the adenovirus, even when used on a nonwoven made of fibers with a fiber length of > 5 mm. Therefore, it is assumed that the combination of an impregnating agent containing alcohol and amino alcohol and a biodegradable nonwoven made of fibers with a fiber length of > 5 mm produces a synergistic effect in the form of pronounced virucidal effectiveness.
[0031] It is considered particularly noteworthy that the virucidal effectiveness of the impregnating agent contained in the wet wipe according to the invention is already evident at comparatively low levels of impregnation. In a preferred embodiment, the nonwoven fabric is therefore impregnated with a maximum impregnation quantity of only 4.0 g of impregnating agent per gram of nonwoven fabric.
[0032] The invention also relates to a method for producing a wet wipe, comprising applying an impregnating agent to a nonwoven fabric, wherein the impregnating agent is a preferably phosphonate-free impregnating agent containing 35-80 wt.% alcohol, which is a C1-C4 alcohol or a mixture of C1-C4 alcohols, and further contains an amino alcohol, a surfactant and water and has a pH in the range of pH 8 to pH 12, and wherein the nonwoven fabric is a biodegradable nonwoven fabric consisting of fibers with a fiber length > 5 mm.
[0033] The wet wipe produced in the process according to the invention has the properties disclosed above with reference to the wet wipe according to the invention as such, which is why the previous description of the wet wipe can also be used to characterize the process in more detail.This means in particular that the amino alcohol contained in the impregnating agent that is applied to the nonwoven fabric is preferably selected from the group comprising or consisting of monoethanolamine, aminomethyl propanol, monoisopropanolamine, tetrahydroxypropylethylenediamine and combinations thereof; the proportion of amino alcohol in the impregnating agent that is applied to the nonwoven fabric is preferably 0.02-5.0 wt%; the proportion of surfactant in the impregnating agent that is applied to the nonwoven fabric is preferably 0.05-5.0 wt%; the impregnating agent that is applied to the nonwoven fabric optionally contains an organic acid; the biodegradable nonwoven fabric to which the impregnating agent is applied is preferably a nonwoven fabric made of viscose and / or lyocell; the impregnating agent is preferably applied to the nonwoven fabric in an impregnating amount of max. 4.0 g of impregnating agent per gram of nonwoven fabric.Furthermore, the invention also relates to the use of a wet wipe according to the invention for disinfecting surfaces, which surfaces can optionally also be animated. However, the use as a surface disinfectant is more preferred.
[0034] Detailed description of the invention
[0035] The invention will now be described in more detail using an embodiment.
[0036] Example 1: Production of wet wipes according to the invention and not according to the invention and
[0037] Comparison of their properties
[0038] To compare the virucidal efficacy of different wet wipes, four different impregnating agents were initially prepared. The composition of the impregnating agents is shown in Table 1 below.
[0039] Table 1 : Composition of impregnating agents 1 to 4
[0040] The impregnating agent 1 is an impregnating agent according to the invention with a pH of 10.0, which contains 45 wt.% ethanol, 0.5 wt.% surfactant, 0.125 wt.% monoethanolamine and the remaining portion water.
[0041] Impregnating agent 2 is a non-inventive impregnating agent with a pH of 10.6, containing 45 wt% ethanol, 0.5 wt% surfactant, and water. It was prepared to investigate the influence of the amino alcohol.
[0042] Impregnating agent 3 is a non-inventive impregnating agent with a pH of 13.1, containing 47.25 wt.% ethanol, 0.5 wt.% surfactant, 0.25 wt.% NaOH, and water. This was prepared to investigate the influence of the missing amino alcohol compared to another pH stabilizer (NaOH). Impregnating agent 4 is a non-inventive impregnating agent with a pH of 9.9, containing 47.25 wt.% ethanol, 0.5 wt.% surfactant, 0.25 wt.% Na2CO3, and water. This was prepared to investigate the influence of the missing amino alcohol compared to another pH stabilizer (Na2CO3).
[0043] For the effectiveness tests, the impregnating agents were applied to three different nonwovens, the composition of which is given in Table 2 below.
[0044] Table 2: Composition of nonwovens 1 to 3
[0045] Nonwoven fabric 1 is made of 100% PET, with a basis weight of 48 g / m 2 . This is therefore not a nonwoven fabric according to the invention, but a non-biodegradable comparison nonwoven fabric.
[0046] Nonwoven fabric 2 is made of 100% Lyocell, with a basis weight of 48 g / m 2 . This is therefore a nonwoven fabric according to the invention.
[0047] Nonwoven fabric 3 consists of 60% viscose and 40% cellulose pulp and also has a basis weight of 48 g / m 2 This is not a nonwoven fabric according to the invention, but rather a biodegradable comparison nonwoven fabric, since cellulose pulp does not contain fibers with a fiber length > 5 mm.
[0048] In separate experiments, each of the impregnating agents 1 to 4 was applied to each of the nonwovens 1 to 3. Approximately 4 weeks after production, the pH value of the impregnating agent and the efficacy against adenovirus were determined according to DIN EN 14476 after a 3-minute exposure time of the wipes obtained in this way.
[0049] Some of the experiments were also conducted with different degrees of impregnation, for example, to demonstrate that a non-inventive combination of nonwoven fabric and impregnating agent does not exhibit the desired virucidal efficacy even at a high degree of impregnation, or to demonstrate that a nonwoven fabric and impregnating agent combination according to the invention exhibits excellent virucidal efficacy even at a low degree of impregnation. In some cases, the so-called wetness gradient index was also determined, which indicates the sagging behavior of the impregnating liquid in a stack of impregnated wipe products, for example, containing 60 or 100 wet wipes stacked on top of one another.To determine the wetness gradient index, after a storage period of one week, the top 5-10 wet wipes of a pack and the bottom 5-10 wet wipes (each the same number) of a pack were removed and weighed, whereby the wetness gradient index is the quotient of the respective masses of the lower and upper wet wipes.
[0050] An overview of the results achieved for selected nonwoven / impregnant combinations is shown in Table 3 below.
[0051] Table 3: Results of selected nonwoven / impregnant combinations
[0052] The results in Table 3 clearly show that only the first two combinations (impregnant 2 + nonwoven fabric 1 and impregnant 1 + nonwoven fabric 2) achieve the reduction in microbial load by more than 4 logs required by DIN EN 14476 after a three-minute exposure time, demonstrating effectiveness against adenovirus. This involves the impregnant according to the invention containing amino alcohol in combination with a lyocell nonwoven fabric (consisting of fibers with a fiber length of > 5 mm), as well as a non-inventive combination consisting of an impregnant without amino alcohol and a non-biodegradable PET nonwoven fabric. The disadvantage of the latter combination is that it is not biodegradable.Furthermore, the log-step reduction is not as great as with the inventive combination, even though the inventive combination used a significantly lower degree of impregnation of only 3.3 g of impregnating agent per gram of nonwoven fabric compared to an impregnation level of 5.5 g of impregnating agent per gram of nonwoven fabric in the non-inventive combination. Another advantage of the inventive combination is that the wetness gradient index in a stack of 100 wipes assumes the same value as in the non-inventive combination in a stack of only 60 wipes. This is because PET nonwoven fabric is very hydrophobic, and the liquid therefore sags so much that packaging with more than 60 wipes is impractical.
[0053] For the third combination listed in Table 3, it is clear that after 3 minutes, it does not achieve the required log reduction of more than 4 logs, and the pH drops significantly. Since the only difference from the second combination according to the invention is the absence of the amino alcohol in the impregnating agent, it is evident that this is essential for the effectiveness of the impregnating agent and the stabilization of the pH.
[0054] The fourth combination listed in Table 3 clearly shows that not every biodegradable nonwoven fabric exhibits the desired virucidal activity when combined with the amino alcohol-containing impregnating agent according to the invention. A nonwoven fabric containing 60% viscose and 40% cellulose pulp was tested. Although the pH was stabilized in the alkaline range, only a log reduction of 2.5 was achieved after 3 minutes, which is insufficient for efficacy against adenovirus.
[0055] The combinations listed in fifth and sixth place in Table 3 show that even two non-inventive comparison combinations on biodegradable nonwoven fabric and impregnating agents containing pH stabilizers other than an amino alcohol cannot achieve the desired virucidal effect.
[0056] Consequently, only the combination according to the invention of a biodegradable nonwoven fabric made of fibers with a fiber length > 5 mm with an alcoholic impregnation agent having an alkaline pH and containing amino alcohol as a pH stabilizer has excellent virucidal activity against adenovirus, even at low impregnation levels.
[0057] The features of the invention disclosed in the above description, in the examples and in the claims may be essential both individually and in any combination for the realization of the invention in its various embodiments.
Claims
Claims 1. A wet wipe for surface disinfection, comprising a biodegradable nonwoven fabric consisting of fibers with a fiber length > 5 mm and impregnated with a phosphonate-free impregnating agent containing 35-80 wt.% alcohol, wherein the alcohol is a C1-C4 alcohol or a mixture of C1-C4 alcohols, and wherein the impregnating agent further contains an amino alcohol, a surfactant and water and has a pH in the range of pH 8 to pH 12.
2. Wet wipe for surface disinfection according to claim 1, characterized in that the amino alcohol contained in the impregnating agent is selected from the group comprising or consisting of monoethanolamine, aminomethyl propanol, monoisopropanolamine, tetrahydroxypropylethylenediamine and combinations thereof.
3. Wet wipe for surface disinfection according to claim 1 or claim 2, characterized in that the impregnating agent has a virucidal effect according to DIN EN 14476.
4. Wet wipe for surface disinfection according to one of the preceding claims, characterized in that the proportion of amino alcohol in the impregnating agent is 0.02-5.0 wt.%.
5. Wet wipe for surface disinfection according to one of the preceding claims, characterized in that the proportion of surfactant in the impregnating agent is 0.05-5.0 wt.%.
6. Wet wipe for surface disinfection according to one of the preceding claims, characterized in that the biodegradable nonwoven fabric consists of viscose and / or lyocell.
7. Wet wipe for surface disinfection according to one of the preceding claims, characterized by an impregnation quantity of max. 4.0 g of impregnating agent per gram of nonwoven fabric. A method for producing a wet wipe according to any one of claims 1 to 7, comprising applying an impregnating agent to a nonwoven fabric, wherein the impregnating agent is a phosphonate-free impregnating agent containing 35-80% by weight of alcohol which is a C1-C4 alcohol or a mixture of C1-C4 alcohols, and further containing an amino alcohol, a surfactant and water and having a pH in the range Range from pH 8 to pH 12, and wherein the nonwoven fabric is a biodegradable nonwoven fabric made of fibers with a fiber length > 5 mm. The method according to claim 8, characterized in that the impregnating agent is applied to the nonwoven fabric in an amount of 4.0 g of impregnating agent per gram of the nonwoven fabric. Use of a wet wipe according to any one of claims 1 to 7 for disinfecting surfaces.