EP2924101A1 - Cleaning agent and method for cleaning dishes - Google Patents

Abstract

The invention relates to a detergent for machine cleaning of dishes. According to the invention it has the following features: a. it contains at least one chelating agent selected from the group consisting of aminopolycarboxylic acids, b. it contains at least one polymeric dispersing assistant and / or at least one aminopolyphosphonic acid, c. the pH is 8 to 12, preferably 8 to 11, more preferably 9 to 11, d. the detergent is enzyme-free, e. the detergent is bleach-free. The invention enables a gentle cleaning of dishes without the use of environmentally harmful agents.

Description

The invention relates to a detergent for machine cleaning of dishes, the use of such a detergent for cleaning dishes and a method for machine cleaning of dishes.

When cleaning crockery so-called commercial dishwashers are used in particular in the commercial sector and in the catering, in which the crockery is cleaned in a relatively short time and is therefore available for reuse. Frequently, such commercial dishwashers are designed as machines with automatic tableware transport, for example as belt washers or box conveyor dishwashers. In the wash tanks of such a dishwasher, cleaning liquor is circulated and rinsed on the dishes and this is covered with it.

The usually short in the commercial sector cleaning period with frequent contamination by difficult to remove impurities such as tea or coffee residues, starch or protein residues usually requires the use of relatively aggressive cleaning agents that are, for example, strongly alkaline, or bleach and / or Contain enzymes. EP 0 578 666 B1 discloses, for example, an enzymatic cleaner.

The invention has for its object to provide a cleaning agent and a method of the type mentioned above, which allow a gentle and effective cleaning of dishes.

1. a. es enthält wenigstens einen Chelatbildner ausgewählt aus der Gruppe bestehend aus Aminopolycarbonsäuren,
2. b. es enthält wenigstens ein polymeres Dispergierhilfsmittel und/oder wenigstens eine Aminopolyphosphonsäure,
3. c. der pH-Wert beträgt 8 bis 12, vorzugsweise 8 bis 11, weiter vorzugsweise 9 bis 11.
4. d. das Reinigungsmittel ist enzymfrei,
5. e. das Reinigungsmittel ist bleichmittelfrei.

This object is achieved by a detergent for machine cleaning of dishes, characterized by the following features:

1. a. it contains at least one chelating agent selected from the group consisting of aminopolycarboxylic acids,
2. b. it contains at least one polymeric dispersing assistant and / or at least one aminopolyphosphonic acid,
3. c. the pH is 8 to 12, preferably 8 to 11, more preferably 9 to 11.
4. d. the detergent is enzyme-free,
5. e. the detergent is bleach-free.

First, some terms used in the invention are explained.

The cleaning agent according to the invention is designed and suitable for the automatic cleaning of dishes. This machine cleaning is usually done in a dishwasher. A dishwasher automatically cleans dishes after startup without manual intervention. The term crockery refers to all in the kitchen area used or usable articles accessible to such automatic cleaning, including trays, gastronorm containers and the like. In the context of the invention, the term dishes additionally includes other objects which are accessible to machine cleaning similar to dishes. By way of example, suitable industrial parts may be mentioned here.

A dishwasher has at least one wash tank. Detergent liquor can be circulated in such a wash tank and rinsed several times over the dishes located in the wash tank. The dishwasher may be designed as a single-tank machine into which the dishes are inserted and remains stationary during the rinsing process. It is preferably a machine with automatic dish transport (for example, a belt or box transport machine) in the harness at intervals or preferably is driven continuously through the dishwasher during the cleaning process. Such a machine can also be designed as a single-tank machine or preferably as a multi-tank machine with at least two washing tanks.

Chelating agents are chemical compounds that form chelate complexes with metal ions. Aminopolycarboxylic acids and aminopolyphosphonic acids are chelating agents known to the person skilled in the art. In the context of the present application, a general term is used for acids, the term encompasses according to the invention the salts of the corresponding acids. In the mildly alkaline cleaning agent according to the invention, the acids will generally be in the form of their salts, they can be used from the outset in the form of salts. Polymeric dispersing aids help to disperse detached soil particles in the solution and thus to keep them in suspension and prevent redeposition on the surface of the cleaned dishes.

As a rule, the cleaning agent according to the invention will initially be present as a sales form in a preferably liquid formulated concentrate, which is diluted with water to form a ready-to-use diluted cleaning solution or cleaning agent liquor. The claimed range of pH can already be present in the concentrate, alternatively it can be present in the ready-to-use diluted cleaner liquor. It is preferably present in the concentrate as well as after its dilution to a ready-to-use detergent solution.

The cleaning agent according to the invention is enzyme-free and bleach-free. In the context of the invention, free of ingredients means that these corresponding ingredients are not added to the cleaning agent in a targeted manner and thus are not contained therein or at most are normally contained as industrial scale impurities.

Bleaching agents are defined in Ullmann's Encyclopedia of Industrial Chemistry, 6th Edition, Vol. 5, p. 411ff , According to the invention, the cleaning agent is preferably in particular free of reactive chlorine compounds with bleaching action.

The invention has recognized that the inventive combination of features makes it possible to provide a cleaning agent which is highly effective, in particular, in commercial dishwashing, which is mildly alkaline and thus less aggressive and can dispense with potentially environmentally harmful ingredients. The invention The chelating agents used (aminopolycarboxylic acids and aminopolyphosphonic acids) are environmentally compatible in comparison with chelating agents customary in the prior art, such as, for example, EDTA or NTA.

According to the invention can be dispensed with high alkalinity, it is also not necessary to use enzymes.

It is particularly surprising that the combination according to the invention can remove conventional impurities such as starch, tea and coffee residues within the scope of conventional commercial dishwashing even without high and thus aggressive alkalinity, without enzymes and without bleaching agents in the commercial kitchen sector. In the prior art, no detergent is known that can provide a corresponding cleaning performance waiving the said ingredients.

The invention makes it possible to provide a cleaning agent which meets the criteria for the EU Ecolabel in accordance with Regulation (EC) No. 66/2010 and the Commission decision of 14 November 2012 laying down the ecological criteria for the award of the EU Ecolabel for industrial and institutional machine dishwashing detergents (2012/720 / EU) and still provide the required cleaning performance.

Surprisingly, it has thus been found that the combination according to the invention provides a cleaning agent which enables effective machine cleaning of dishes, in particular in the commercial sector, without ingredients considered essential in the prior art. Especially The cleaning agent according to the invention preferably contains both aminopolycarboxylic acids and aminopolyphosphonic acids as well as polymeric dispersing aids.

• Tensiden,
• Phosphaten,
• Bioziden,
• Farbstoffen,
• EDTA.

The cleaning agent according to the invention is preferably free from one or more of the following ingredients:

• surfactants,
• phosphates,
• biocides,
• dyes,
• EDTA.

Preferably, the cleaning agent is free of several of these ingredients, more preferably it does not contain any of the ingredients mentioned.

The term surfactants refers to surfactants as defined in Ullmann's Encyclopedia of Industrial Chemistry, 6th Edition, Vol. 35, p. 293ff in the section "Surfactants".

Phosphates are salts and esters of phosphoric acid including their condensates or polymers.

Biocides are active substances and preparations which contain one or more active substances, in the form in which they reach the user, and which are intended to destroy, deter, render harmless, prevent damage by them chemically or biologically or to combat it in another way (Article 2 of Directive 98/8 / EC of the European Union Parliament and of the Council of 16 February 1998 concerning the placing of biocidal products on the market).

Dyes are colorants acc. DIN 55943, in particular soluble dyes.

The aminopolycarboxylic acids and / or aminopolyphosphonic acids may preferably be tridentate or tetradentate according to the invention.

Among the aminopolycarboxylic acids, MGDA (methylglycine-N, N-diacetic acid) and / or GLDA (glutamic acid-N, N-diacetic acid) are preferred, particularly preferably both are present in the cleaning agent according to the invention. NTA as an impurity in the MGDA and GLDA used is preferably not present or at most in concentrations of less than 1% by weight in the raw material used and less than 0.1% by weight in the cleaning agent according to the invention.

The cleaning agent according to the invention preferably fulfills the criteria for the EU Ecolabel according to Regulation (EC) No. 66/2010 and the Commission's decision of 14 November 2012 establishing the ecological criteria for the award of the EU Ecolabel for industrial industrial dishwashing detergents and institutional area (2012/720 / EU).

• EDTA,
• reaktive Chlorverbindungen,
• NTA als Verunreinigung in MGDA und GLDA (Grenzwerte s.o.),
• Gesamtgehalt an Phosphor (Kriterium 3(g)).

In particular, criterion 3 of the abovementioned decision (prohibited or restricted substances or mixtures) is preferred. The following substances mentioned in this criterion 3, which may not be included or only within prescribed limits, are particularly emphasized, since it was problematic in the prior art to use a the machine cleaning suitable detergent without producing these substances:

• EDTA,
• reactive chlorine compounds,
• NTA as impurity in MGDA and GLDA (limit values see above),
• Total phosphorus content (criterion 3 (g)).

The total content of phosphates and other phosphorus compounds shall not exceed the following limit values, measured in grams of phosphorus per liter of water, at the maximum intended dosage of the detergent according to the invention: Soft water (0-6 ° dH): 0.15 g / l Medium hard water (7-13 ° dH): 0.30 g / l Hard water (> 14 ° dH): 0.50 g / l

The aminopolyphosphonic acids preferably comprise ATMP (amino-tris (methylenephosphonic acid) or salts thereof.

A preferred polymeric dispersing aid comprises polyacrylic acids and / or polymethacrylic acids, or salts thereof. These molar masses preferably have between 2,000 and 20,000, more preferably 4,000 and 15,000, more preferably 6,000 and 10,000.

The cleaning agent preferably additionally contains a corrosion inhibitor. It may be a substance that binds or complexes iron ions and thus inhibits corrosion. Preferred is a phosphonocarboxylic acid, more preferred is PBTC (2-phosphonobutane-1,2,4-tricarboxylic acid). Here too, salts may optionally be used or are preferred.

According to a further variant of the invention, the cleaning agent preferably contains an alkali source, preferably an alkali metal hydroxide, more preferably KOH. The pH may be adjusted as desired, more preferably in the range of 9-11 and about 10, respectively.

1. a. Aminopolycarbonsäuren 3 bis 15, vorzugsweise 5 bis 10,
2. b. polymere Dispergierhilfsmittel 1 bis 5, vorzugsweise 2 bis 4,
3. c. Polyphosphonsäuren 0,5 bis 3, vorzugsweise 1,5 bis 2,5,
4. d. Korrosionsinhibitor 0,5 bis 3, vorzugsweise 1 bis 2,

e. Alkaliquelle, berechnet als KOH, 0,3 bis 2, vorzugsweise 0,5 bis 1,5.The cleaning agent according to the invention has an active ingredient combination in which the ingredients described are preferably present in a certain weight ratio to each other. The relative proportions by weight of the ingredients, if any, may be as described below. "If present" means in optional or optional ingredients that the range of shares described only applies if the corresponding ingredient is actually included in the particular embodiment of the invention.

1. a. Aminopolycarboxylic acids 3 to 15, preferably 5 to 10,
2. b. polymeric dispersing aids 1 to 5, preferably 2 to 4,
3. c. Polyphosphonic acids 0.5 to 3, preferably 1.5 to 2.5,
4. d. Corrosion inhibitor 0.5 to 3, preferably 1 to 2,

e. Alkali source, calculated as KOH, 0.3 to 2, preferably 0.5 to 1.5.

Calculated as KOH means that the proportion by weight of the alkali source used is converted by its hydroxy groups into the equivalent amount of KOH.

1. a. Aminopolycarbonsäuren 3 bis 15, vorzugsweise 5 bis 10 Gew.-%,
2. b. polymere Dispergierhilfsmittel 1 bis 5, vorzugsweise 2 bis 4 Gew.-%,
3. c. Polyphosphonsäuren 0,5 bis 3, vorzugsweise 1,5 bis 2,5 Gew.-%,
4. d. Korrosionsinhibitor 0,5 bis 3, vorzugsweise 1 bis 2 Gew.-%,
5. e. Alkaliquelle, berechnet als KOH, 0,3 bis 2, vorzugsweise 0,5 bis 1,5 Gew.-%.

The salable form of the cleaning agent according to the invention may preferably be formulated as a liquid and more preferably as a concentrate, which is diluted with water at or immediately before use. According to the invention, it is preferred that such a concentrate contains the respective ingredients, if present, in the absolute parts by weight listed below:

1. a. Aminopolycarboxylic acids 3 to 15, preferably 5 to 10,% by weight,
2. b. polymeric dispersing agents 1 to 5, preferably 2 to 4 wt .-%,
3. c. Polyphosphonic acids 0.5 to 3, preferably 1.5 to 2.5 wt .-%,
4. d. Corrosion inhibitor 0.5 to 3, preferably 1 to 2 wt .-%,
5. e. Alkali source, calculated as KOH, 0.3 to 2, preferably 0.5 to 1.5 wt .-%.

Such a concentrate can be diluted with water to a cleaner solution or cleaner fleet. It can be used in this detergent liquor in a concentration of 0.1 to 2 wt .-%, preferably 0.1 to 1 wt .-%, more preferably 0.2 to 0.5 wt .-% are used.

In the detergent liquor used, the absolute concentrations of the respective ingredients, if present, are thus preferably in a range which is smaller by a factor of 50-1,000, more preferably 100-1,000, further preferably 200-500, than the preferred absolute weight proportions of the one described above concentrate. The absolute weights to be calculated therefrom in the cleaning liquor used are expressly likewise the subject matter of the disclosure of the present patent application.

The invention also relates to the use of a cleaning agent according to the invention for cleaning dishes, in particular for removing contaminants selected from the group consisting of coffee and tar residues and starch and protein residues of dishes.

1. a. optional Vorspülen,
2. b. Reinigen mit einem erfindungsgemäßen Reiniger,
3. c. Klarspülen.

Likewise provided by the invention is a method for the automated cleaning of dishes, with the steps:

1. a. optional pre-wash,
2. b. Cleaning with a cleaner according to the invention,
3. c. Rinse.

The optional pre-rinsing and rinsing are carried out in a manner familiar to the person skilled in the art and require no further explanation here. The rinsing may be followed by further steps such as drying.

In the context of the method according to the invention, the cleaning in step b. over a period of 10 seconds to 10 minutes, more preferably 2 to 6 minutes.

The cleaning may preferably take place at a temperature of 20 to 80 ° C, preferably 30 to 70 ° C, more preferably 50 to 70 ° C. The described preferred time period and preferred temperature range are independently of each other subject matter and parameters of the present invention.

The cleaning preferably takes place in step b. with an aqueous dilution of a concentrate described above and exemplified in the following examples. This concentrate is preferably used in a concentration of 0.1 to 2 wt .-%, more preferably 0.1 to 1 wt .-%, more preferably 0.2 to 0.5 wt .-%.

Embodiments of the invention will be described below.

example 1

A recipe for a detergent according to the invention is as follows: Proportion [% by weight] Active ingredient [% by weight] PAS 8000 N, 45% 5.00 2.25 ATMP, 5% Na, 40% 5.00 2.00 MGDA, 3 Na, 40% 9.00 3.60 GLDA, 4 Na, 47% 9.00 4.23 PBTC, 50% 3.00 1.5 KOH, 45% 2.10 0.95 Water, demineralized 66,90

The recipe ingredients are mixed and stirred for 15 min at room temperature until a clear solution is formed. The concentrate obtained has a pH of 10.

Example 2

• neodisher® BioClean (enzymatischer Reiniger Fa. Dr. Weigert)
• neodisher® Alka 240 (stark ätzalkalischer Reiniger Fa. Dr. Weigert)
• neodisher® Alka 440 (stark ätzalkalischer Reiniger Fa. Dr. Weigert, zusätzlich enthaltend Natriumchlorit)

In this example, the cleaning performance of the formulation according to Example 1 is compared with enzymatic and strong alkaline detergents of the prior art. The following cleaning agents were used as comparison (not according to the invention):

• neodisher® BioClean (enzymatic cleaner Fa. Dr. Weigert)
• neodisher® Alka 240 (strongly caustic-alkaline cleaner, Dr. Weigert)
• neodisher® Alka 440 (strongly caustic-alkaline cleaner from Dr. Weigert, additionally containing sodium chlorite)

In a total of four comparative experiments, the detergent of Example 1 was tested in three different commercial dishwashing machines in comparison with the three prior art detergents mentioned. In each case identical cleaning concentrations of the cleaning agents and identical cleaning conditions (process conditions) were used and each identically polluted partial batches of contaminated dishes (contaminated with starch, protein, coffee and tar residues) cleaned. The cleaning results were evaluated by visual inspection, the differences in cleaning with the cleaning agent according to the invention are shown in the table below in the column "Result". It can be seen that the cleaning agent according to the invention achieves an improved cleaning performance despite the omission of alkalinity and enzymes, bleaches and the like. comparison cleaning dishwasher dosage Temperature in the wash tank contact time Result neodisher BioClean Hobart band Dishwasher 3 g / l 64 ° C 2 min Better removal of coffee and tar residues. Equal good removal of starch and protein. Lower dirt deposit in the machine tank neodisher BioClean Miele G 7760 3 g / l 55 ° C 2 min Better removal of coffee and tar residues. Equal good removal of starch and protein. Lower dirt deposit in the machine tank neodisher Alka 240 Hobart band Dishwasher 2.1 g / l 62 ° C 130 sec Equally good for removal of coffee, tea, starch and protein neodisher Alka 440 Winterhalter STR 1 tank machine 2.5 g / l 64 ° C 3 min Better removal of starch, coffee and tea. Equally good protein removal. Striking was the "shiny" dishes

Claims (15)

Cleaning preparations for machine cleaning of dishes, characterized by the following features: a. it contains at least one chelating agent selected from the group consisting of aminopolycarboxylic acids, b. it contains at least one polymeric dispersing assistant and / or at least one aminopolyphosphonic acid, c. the pH is 8 to 12, preferably 8 to 11, more preferably 9 to 11, d. the detergent is enzyme-free, e. the detergent is bleach-free. Detergent according to claim 1, characterized in that it is free of one or more of the following ingredients: - surfactants, - phosphates, - biocides, - dyes, - EDTA. Cleaning agent according to claim 1 or 2, characterized in that the aminopolycarboxylic acids and / or Aminopolyphosphonsäuren are tridentate or tetradentate. Detergent according to claim 3, characterized in that the aminopolycarboxylic acids comprise MGDA and / or GLDA. Detergent according to claim 3 or 4, characterized in that the aminopolyphosphonic acids comprise ATMP. Cleaning agent according to one of claims 1 to 5, characterized in that the polymeric dispersing aid comprises polyacrylic acids and / or polymethacrylic acids. Cleaning agent according to claim 6, characterized in that the polyacrylic acids and / or polymethacrylic acids have molecular weights of between 2,000 and 20,000, preferably 4,000 and 15,000, more preferably 6,000 and 10,000. Detergent according to one of claims 1 to 7, characterized in that it additionally contains a corrosion inhibitor, preferably a phosphonocarboxylic acid, more preferably PBTC. Cleaning agent according to one of claims 1 to 8, characterized in that it contains an alkali source, preferably an alkali hydroxide, more preferably KOH. Detergent according to one of claims 1 to 9, characterized in that it formulated as a liquid is. Detergent according to Claim 10, characterized in that it is formulated as a concentrate and in that the proportions by weight of the ingredients, if present, are as follows: a. Aminopolycarboxylic acids 3 to 15, preferably 5 to 10,% by weight, b. polymeric dispersing agents 1 to 5, preferably 2 to 4 wt .-%, c. Polyphosphonic acids 0.5 to 3, preferably 1 to 2 wt .-%, d. Corrosion inhibitor 0.5 to 3, preferably 1 to 2 wt .-%, e. Alkali source, calculated as KOH, 0.3 to 2, preferably 0.5 to 1.5 wt .-%. Use of a cleaning agent according to any one of claims 1 to 11 for the cleaning of dishes, in particular for the removal of soils selected from the group consisting of coffee and tar residues and starch and protein residues of dishes. Method for machine cleaning of dishes, with the steps: a. optional pre-wash, b. Cleaning with a cleaner according to one of claims 1 to 11, c. Rinse. A method according to claim 13, characterized in that the cleaning in step b. over a period of 10 seconds to 10 minutes, preferably 2 to 6 minutes, at a temperature of 20 to 80 ° C, preferably 30 to 70 ° C, more preferably 50 to 70 ° C takes place. A method according to claim 13 or 14, characterized in that the cleaning in step b. with an aqueous dilution of a concentrate according to claim 11 and this concentrate in a concentration of 0.1 to 2 wt .-%, preferably 0.1 to 1 wt .-%, more preferably 0.2 to 0.5 wt. -% is used.