EP3322791B1 - Cleaning tablet for carafes - Google Patents

Description

The field of the present invention is that of cleaning products for the inside of carafes, in particular wine decanters, for removing wine residues and limescale stains.

The cleaning of the inside of carafes in general and of wine decanters in particular represents a challenge in gastronomy and household, especially the more intricate these vessels are designed (e.g. by providing a narrow, longer neck). The cleaning result achieved with conventional cleaning methods (e.g. using a brush) is usually unsatisfactory - at least after a reasonable amount of work - often not all areas of the inside are accessible for such cleaning methods.

A particular problem is the avoidance of lime residues (lime haze, lime streaks, lime stains) on the inside of the carafe, which are usually extremely visible due to the mostly fine cut and the sometimes high crystal glass quality of the carafes and can leave an unsightly impression. The clearly visible residues of wine, especially red wine, are usually difficult to remove.

It should also be noted that conventional cleaning methods (e.g. using a brush) are sometimes abrasive and, after repeated use over a long period of time, cause the carafe to become cloudy, which can also leave an unaesthetic impression. Thorough cleaning that can be achieved with a reasonable amount of work can also be essential for reasons of hygiene and taste, especially in gastronomy.

Various methods and products are known in the prior art which deal with the problems described at the outset.

For example, "cleaning pearls" (eg made of metal) for carafes, in particular for wine decanters, are sold, which are intended to remove impurities on the inside of the carafe by mechanical action when the carafe is agitated. The cleaning is sometimes not successful, there are bottlenecks inaccessible to the cleaning beads due to their size and repeated use over a long period of time can scratch the inside of the carafe. In addition, the handling of the cleaning beads is rather complex.

Comparatively complicated devices for cleaning carafes are also known:
The EP 1 891 871 A2 relates to a device for polishing or cleaning or drying an inside of a vessel used for containing liquids, in paragraph [0001] of the document a carafe is mentioned as a possible vessel.

The US 2014/0283877 A1 also discloses a device for cleaning vessels, in particular wine decanters (cf. paragraph [0024] of the document).

The large number of home remedies, discussions, advice and the like on the Internet shows that the state of the art has not yet solved the problem of cleaning the inside of carafes to the satisfaction of the household or gastronomy.

It is therefore an object of the present invention to provide an easy-to-handle product or method for cleaning the inside of carafes, in particular wine decanters. In particular, the removal of wine or lime residues should be made easier. Furthermore, the formation of limescale residues from the cleaning itself should be avoided as far as possible. Ultimately, the formation of scratches, clouding and/or discoloration on the inside should also be curbed or prevented over a longer period of time as a result of repeated use of the present invention, in comparison to methods or products for cleaning known in the prior art.

Therefore the present invention provides a cleaning tablet. The detergent tablet according to the present invention comprises bicarbonate, citric acid, surfactant, bleach, bleach activator and complexing agent, wherein the complexing agent is methylglycine diacetic acid (MGDA) or a salt thereof. The combined mass fraction of bicarbonate and citric acid in the cleaning tablet according to the invention is 30%-70%, and the molar ratio between bicarbonate and citric acid is between 1:1 and 4:1

It has surprisingly turned out that with the cleaning tablet according to the invention - in contrast to products and processes in the prior art - no stronger mechanical action on the inside of the carafe (e.g. by brushing) for satisfactory cleaning (e.g. of limescale or red wine residues ) is necessary. The prior art does not know such cleaning tablets for carafes; probably because it was previously assumed that in any case stronger mechanical action on the inside (e.g. by brushing or "cleaning pearls") is necessary for satisfactory cleaning. Among other things, the high mass fraction according to the invention of hydrogen carbonate and citric acid in the cleaning tablet (e.g. compared to "dishwasher tabs") in the molar ratio according to the invention causes the formation of gas bubbles of carbon dioxide when the cleaning tablet dissolves. As was surprisingly discovered in the course of the present invention, the rising of these gas bubbles ("bubbling") in the carafe usually represents a sufficient mechanical action for satisfactory cleaning to remove residues from the inside (especially lime or limescale deposits). Wine residues, especially red wine residues), especially in combination with other components of the cleaning tablet according to the invention. Unlike, for example, brushes or "cleaning pearls", the relatively small gas bubbles can also reach areas of the inside of the carafe that are otherwise difficult to reach.

In the course of the present invention, it has also surprisingly been found that the relatively large amount of water softener (citrate) reproduced in situ - by the reaction of hydrogen carbonate and citric acid when dissolving the tablet - has a positive effect on the removal of limescale stains or on the Avoiding the formation of new limescale has, especially in conjunction with other components of the cleaning tablet according to the invention.

Furthermore, the mass fraction of hydrogen carbonate and citric acid, as provided in the invention, in the intended molar ratio means that tablet disintegrants in the cleaning tablet can be dispensed with.

Although is through the EP 0 334 060 A2 a cleaning tablet for dentures is known, which can contain 10-30% by weight of sodium bicarbonate and 5-20% by weight of citric acid or citrate salts and other similarly acting organic acids or their salts (p. 6 of the document). however, there is no specific disclosure of a cleaning tablet with the mass fraction of bicarbonate and citric acid provided according to the invention in the molar ratio provided according to the invention. The denture cleaning tablet disclosed in the specific exemplary embodiment of the document contains only 20% by weight sodium bicarbonate (ie actually only about 14.5% by weight bicarbonate) and 7% by weight sodium citrate (not citric acid). In addition, the provision of a flavoring substance typical of denture cleaning tablets (0.5% by weight of peppermint powder) in the exemplary embodiment of the document makes it clear that the denture cleaning tablets are unsuitable for use according to the present invention, because flavoring substances typical of denture cleaning tablets in particular (also in traces) affect the sense of taste when enjoying the water or, to a greater extent, the wine from the carafe.

The US 2014/0000658 A1 relates to a composition for cleaning and its use. This composition includes an oxidizing agent, sodium carbonate or sodium bicarbonate, a weak acid, and combinations of certain detergents. According to the document, the composition does not contain an additional complexing agent such as MGDA, for example, nor does the document deal with cleaning the inside of carafes, in particular wine decanters. These are not even mentioned in the document.

The U.S. Patent No. 6,914,368 relates to a tablet dishwashing product having at least two layers comprising, inter alia, a bleaching agent, a bleach activator and a silver/copper corrosion inhibitor. A cleaning tablet with the mass fraction of hydrogen carbonate and citric acid provided according to the invention in the molar ratio provided according to the invention is not disclosed therein. In addition, the document does not deal with the cleaning of the inside of carafes, especially wine decanters.

The DE 199 26 376 A1 relates to shelf-stable effervescent tablets, containing organic acids and carbonates or hydrogen carbonates. It neither discloses a cleaning tablet with the mass fraction of hydrogen carbonate and citric acid provided according to the invention in the molar ratio provided according to the invention, nor does the document attempt to solve the task of cleaning carafes, in particular wine decanters.

The U.S. 2006/0252666 A1 , the WO 03/089560 A2 and that U.S. Patent No. 5,384,062 relate to further cleaning compositions or further cleaning tablets which may contain citric acid, carbonate or bicarbonate. However, these documents neither anticipate nor lead to the present invention.

As a rule, the cleaning tablet is used as follows: The carafe is pre-filled with warm tap water and the cleaning tablet is placed in the carafe to dissolve. The dissolved cleaning tablet is allowed to act on the inside of the carafe for 10 to 20 minutes (or even overnight), after which the carafe is rinsed out several times with tap water until no more foam is visible. Since the capacity of the citrate formed in situ for the complexing of limescale depends on the temperature, a water temperature of 40°C-50°C is recommended at the beginning of the cleaning - the use of much hotter water is usually to be avoided.

The combined mass fraction of bicarbonate and citric acid in the cleaning tablet according to the invention is preferably at least 32%, more preferably at least 34%, even more preferably at least 36%. Furthermore, the combined mass fraction of hydrogen carbonate and citric acid in the cleaning tablet according to the invention is preferably at most 65%, more preferably at most 60%, even more preferably at most 55%, in particular at most 50%. The bicarbonate is preferably present as sodium bicarbonate or potassium bicarbonate, in particular potassium bicarbonate, in the cleaning tablet according to the present invention. The citric acid is preferably present in an anhydrous form in the cleaning tablet according to the invention. In addition, citrate (e.g. trisodium citrate as a complexing agent) and/or carbonate (e.g. sodium carbonate) can also be used in the cleaning tablet. be included.

In a preferred embodiment of the present invention, the molar ratio between bicarbonate and citric acid in the cleaning tablet is between 1.5:1 and 3.75:1, preferably between 2:1 and 3.5:1, more preferably between 2.5: 1 and 3.25:1, more preferably between 2.75:1 and 3.125:1, especially substantially at 3:1 as this corresponds to the stoichiometry of the reaction of bicarbonate with citric acid when dissolving the detergent tablet.

In a particularly preferred embodiment of the present invention, the pH when the cleaning tablet is dissolved in water is between 6.5 and 8.5, in particular between 7 and 8 or even between 7.25 and 7.75. When the cleaning tablet is dissolved in water, the pH is very particularly preferably above 6.5 and below 7.5, preferably above 6.6 and below 7.4, more preferably above 6.7 and below 7.3. even more preferably above 6.8 and below 7.2, especially above 6.9 and below 7.1. In order to determine the pH value according to the invention, the cleaning tablet (e.g. with a mass of 10 grams) can be introduced into a volume of 100 ml, 250 ml, 500 ml or 1000 ml of water, for example. The pH of the solution can then be measured using a commercially available pH meter.

In comparison to commercially available "dishwasher tabs" (pH 10-11) or, for example, also the denture cleaning tablet in the exemplary embodiment already mentioned EP 0 334 060 A2 (pH 9), the pH of the cleaning tablet according to the invention after dissolution is therefore more in the neutral than in the alkaline range. Although this may reduce the cleaning effect on grease residues, which are not part of the usual dirt on carafes anyway, it is much gentler on the inside of the carafe, especially if it is made of glass. A more alkaline pH promotes "glass corrosion"; with repeated use of more alkaline cleaning tablets over a longer period of time, clouding or streaking of the sometimes very valuable carafe would have to be expected. Thus, in this embodiment of the invention, the cleaning tablet is particularly suitable for use in cleaning the inside of a carafe.

Particularly well suited as surfactants in the invention Cleaning tablets are low-foaming surfactants. Therefore, in a preferred embodiment, the surfactant of the cleaning tablet according to the invention is selected from the group of low-foaming anionic, nonionic and zwitterionic surfactants and mixtures thereof. The anionic surfactants are preferably selected from the group of branched C ₆ -C ₁₂ -alkyl sulfates and their mixtures. The nonionic surfactants are preferably alkoxylated fatty alcohols, in particular ethoxylated and/or propoxylated fatty alcohols, and mixtures thereof. The zwitterionic surfactants preferably come from the group consisting of the C ₆ -C ₁₂ -alkyliminopropionates, C ₆ -C ₁₂ -alkylamidopropyl betaines and mixtures thereof. Surfactants selected from the group consisting of isooctyl sulfates, isooctyl sulfosuccinates, alkoxylated fatty alcohols, capryliminopropionates, caprylamidopropyl betaines and mixtures thereof are particularly preferred. The surfactants are very particularly preferably selected from the group of alkoxylated fatty alcohols, preferably ethoxylated and/or propoxylated C ₁₂ -C ₁₄ fatty alcohols and mixtures thereof, such as ^MARLOX® MO 154 (manufacturer: Sasol Ltd., South Africa). The mass fraction of the surfactants in the cleaning tablet according to the invention is preferably 0.5% to 5%, in particular 1%-3%.

In the context of the present invention, bleach systems (i.e. bleach and bleach activator) give particularly good results when they are designed for low temperature use (at a temperature up to 50°C, in particular between 40°C-50°C). Therefore, in a further preferred embodiment of the present invention, the bleach activator and bleaching agent of the cleaning tablet are suitable for use at a temperature between 40°C-50°C. Preferably the bleach system is a percarbonate/tetraacetylethylenediamine (TAED) system or a percarbonate/4-decanoyloxybenzoic acid (DOPA) system or a similar system.

The complexing agent in the cleaning tablet of the present invention is MGDA (or a salt thereof). In a highly preferred embodiment, the cleaning tablet according to the invention contains, as a complexing agent, optionally, inter alia, methylglycine diacetic acid or a salt thereof, and phosphonate, e.g. hydroxyethylidene-1,1-diphosphonic acid.

According to a further preferred embodiment of the present invention, the cleaning tablet is free from enzymes, perfumes (flavorings) and/or polycarboxylates. Enzymes are used in commercially available cleaning agents to remove heavy soiling (e.g. residues from pasta, eggs, milk). These are usually not necessary for the cleaning of carafes, and residues of the enzymes after cleaning can, for example, impair the taste quality of a wine. Flavorings can also negatively affect the taste quality of water or wine. Polycarboxylates (used as builders in commercially available cleaning agents), in turn, can form deposits on glass that are visible to the naked eye, which is also undesirable in accordance with the invention.

The cleaning tablet according to the invention is water-soluble because residues on the inside of the carafe, which are visible at least to the naked eye, are undesirable after cleaning. In a preferred embodiment of the present invention, the cleaning tablet dissolves in a period of at least 10 seconds, preferably at least 20 seconds, more preferably at least 30 seconds, even more preferably at least 1 minute, in particular at least 2 minutes and at most 30 minutes, preferably at most 20 minutes , more preferably at most 15 minutes, even more preferably at most 10 minutes, in particular at most 5 minutes in water at a temperature of 30° C. at normal pressure.

In a further preferred embodiment of the present invention, the cleaning tablet releases at least 0.1 g, preferably at least 0.25 g, more preferably at least 0.5 g, even more preferably at least 1 g, in particular at least 1 5g or even at least 1.8g of carbon dioxide gas released.

In a further preferred embodiment of the present invention, the cleaning tablet has one or more breaking notches in order, for example, to enable the cleaning tablet to be crushed for use in very narrow-necked carafes.

The cleaning tablet according to the invention can also comprise tabletting aids and/or a tablet disintegrant.

If necessary, the person skilled in the art can provide further ingredients for the tablet according to the invention.

In a further aspect, the present invention provides for the use of the cleaning tablet for cleaning the inside of a carafe, preferably made of glass, in particular crystal glass. Preferably the carafe is a wine decanter.

In a preferred embodiment, the use according to the invention is characterized in that wine residues, in particular red wine residues, and/or lime residues are removed from the inside of the carafe to a significant extent.

In a further preferred embodiment, the use according to the invention is characterized in that the formation of deposits, in particular lime residues, on the inside of the carafe after use is essentially prevented.

During the use according to the invention, the carafe can be additionally agitated during the dissolving of the cleaning agent and/or after the dissolving of the cleaning agent in order to accelerate the cleaning if necessary.

1. A) Einbringen der erfindungsgemäßen Reinigungstablette in die Karaffe; und
2. B) Einbringen von einer wässrigen Flüssigkeit, insbesondere von Wasser, in die Karaffe zum Lösen der Reinigungstablette; und
3. C) Aussetzen der Innenseite der Karaffe der sich lösenden Reinigungstablette; und vorzugsweise
4. D) Aussetzen der Innenseite der Karaffe der Reinigungstablettenlösung für zumindest 1 Minute, bevorzugt für zumindest 10 Minuten, mehr bevorzugt für zumindest 20 Minuten, noch mehr bevorzugt für zumindest 1 Stunde, insbesondere für zumindest 4 Stunden.

In a further aspect, the present description relates to a method comprising the following steps:

1. A) introducing the cleaning tablet according to the invention into the carafe; and
2. B) introducing an aqueous liquid, in particular water, into the carafe to dissolve the cleaning tablet; and
3. C) exposing the inside of the carafe to the dissolving cleaning tablet; and preferably
4. D) exposing the inside of the carafe to the cleaning tablet solution for at least 1 minute, preferably at least 10 minutes, more preferably at least 20 minutes, even more preferably at least 1 hour, especially at least 4 hours.

The same preferred embodiments apply to this method as set out above for the use according to the invention and vice versa.

The cleaning tablet according to the invention is particularly suitable for cleaning carafes, in particular wine decanters—preferably made of glass, in particular of (high-quality) crystal glass. In general, however, the cleaning tablet of the present invention is also suitable for the gentle cleaning (eg for removing lime stains) of other narrow-necked and/or tortuous vessels which are designed in particular to contain water. This can include: vases, (sports) drinking bottles, thermos flasks and CAMELBAK ^® drinking bags (manufacturer: CamelBak Products, LLC; USA).

The present invention is illustrated by the following example to which it is of course not limited.

Example

The following ingredients were compressed into a cleaning tablet with a mass of 10 grams: Designation mass fraction Class potassium bicarbonate 29.0% bicarbonate Citric Acid (anhydrous) 20.0% citric acid Methylglycine diacetic acid trisodium salt 20.0% complexing agent Sodium percarbonate 10.0% bleach Trisodium citrate (anhydrous) 8.0% citrate Hydroxyethylidene -1,1-diphosphonic acid 1.0% complexing agent (phosphonate) ^Marlox® MO 154 2.0% surfactant Polyethylene Glycol 4000 5.0% tabletting aids polyvinylpyrrolidine K15 1.0% tablet disintegrant Tetraacetyl ethylenediamine (TAED) 4303 2.0% bleach activator sodium 2.0% carbonate total 100.0%

The mass fraction of hydrogen carbonate (approximately 61% of the mass fraction of potassium hydrogen carbonate specified above, calculated from the molar mass of hydrogen carbonate or potassium hydrogen carbonate) in this cleaning tablet is around 18%. Together with the citric acid it contains, this results in a combined mass fraction of hydrogen carbonate and citric acid of around 38% in this cleaning tablet. Expressed in amounts of substance, this cleaning tablet has a mass of 10 grams around 29 mmol bicarbonate and around 10 mmol citric acid. The molar ratio between hydrogen carbonate and citric acid in this cleaning tablet is therefore about 3:1.

A wine decanter soiled with red wine residue ( Model Eve from Riedel Glas Austria, volume 1.4L, item no. 1950/09 ) was filled with tap water (temperature: 40°C, water hardness: 15 dH°). The cleaning tablet was then placed in the wine decanter and dissolved in the tap water within 2.5 minutes with strong formation of carbon dioxide bubbles. After 20 minutes at room temperature, the wine decanter was emptied and rinsed three times with tap water (temperature: 10°C, water hardness: 15 dH°). Red wine residues were no longer detectable with the naked eye, and no limescale spots were visible to the naked eye.

Claims (7)

1. Cleaning tablet, characterised in that it comprises bicarbonate, citric acid, surfactant, bleaching agent, bleach activator and a further complexing agent,

   the combined mass fraction of bicarbonate and citric acid in the cleaning tablet being 30% - 70%, and the molar ratio between bicarbonate and citric acid in the cleaning tablet being between 1:1 and 4:1, preferably between 2:1 and 3.5:1, in particular substantially 3:1,

   the further complexing agent being methylglycinediacetic acid, or a salt thereof.
2. Cleaning tablet according to claim 1, characterised in that the pH when the cleaning tablet is dissolved in water is between 6.5 and 8.5, in particular between 7 and 8.
3. Cleaning tablet according to claim 1 or 2, characterised in that the surfactant is a low-foaming surfactant selected from the group of anionic, non-ionic and zwitterionic surfactants and mixtures thereof.
4. Cleaning tablet according to any of claims 1 to 3, characterised in that bleach activator and bleaching agent are designed for low-temperature use.
5. Cleaning tablet according to any of claims 1 to 4, characterised in that the cleaning tablet comprises phosphonate as an additional complexing agent.
6. Cleaning tablet according to any of claims 1 to 5, characterised in that it is free of enzymes, polycarboxylates, and/or perfumes.
7. Use of the cleaning tablet according to any of claims 1 to 6 for cleaning the inside of a decanter, in particular a wine decanter, preferably to remove limescale residues and/or wine residues.