EP1349912B1 - Use of low foam percarboxlic acid based products containing surfactants for cip-desinfection - Google Patents

Abstract

The use of an agent containing surfactant components chosen from sulfonic acids or sulfonates, alkylamine oxides, ethercarboxylic acids, and alkylether sulfates, in total amounts of 0.01 to 1 wt. %, preferably 0.05 to 0.5 wt. %, with respect to the entire agent, and also one or more percarboxylic acids chosen from a) those peracids or salts of peracids with general formula (I) R<SUP>2</SUP>-O<SUB>2</SUB>C-(CH<SUB>2</SUB>)<SUB>x</SUB>-CO<SUB>3</SUB>H in which R<SUP>2 </SUP>is hydrogen or an alkyl group with 1 to 4 carbon atoms and x is a number from 1 to 4, and/or b) phthalimido-percarboxylic acids (II), in which the percarboxylic acid segment contains 1 to 18 carbon atoms, and/or c) compounds of the formula (III) R<SUP>1</SUP>-CO<SUP>3</SUP>H in which R<SUP>1 </SUP>is an is an alkyl or alkenyl group with 1 to 18 carbon atoms, for disinfection purposes in CIP processes.

Description

The present invention relates to the use of low-foaming, surfactant-containing Percarboxylic acid agent for CIP disinfection.

The use of halogen-releasing substances, halocarboxylic acids such as Monobromoacetic acid, oxidative compounds such as chlorine dioxide, peracetic acid, Active chlorine, as well as other antimicrobial substances such as isothiazolinones for cleaning and / or disinfection of hard surfaces is known.

Furthermore, in K. H. Wallhäusser "Sterilization, Disinfection and Preservation Practice", 5th ed. (1995) and from H. P. Fiedler "Encyclopedia of excipients for Pharmacy, Cosmetics and Adjacent Areas ", 3rd ed. (1989) numerous antimicrobial effective means such as a. also oxidative agents, organic acids, phenyl compounds or guanidines and numerous other compounds.

Depending on the chosen formulation, for example when combined with foaming Surfactants, it may be that such agents in the cleaning solution the Promote formation of foam, which, for example, in some of the applications the food manufacturing industry but also in the pharmaceutical or cosmetic industry etc. is not desired.

In particular, in the CIP cleaning process, there is a need for means in which Use the foam behavior does not interfere and at the same time a particularly good wetting the surface to be treated is achieved.

Accordingly, the object of the present invention was to simple To seek means in their use in disinfection in the CIP process a very good disinfection result is achieved and at the same time the wetting properties be positively influenced, without one for the CIP process disturbing foam behavior would be observed.

Before discussing the solution of the problem in the following, it is necessary to explain what the present invention means by CIP methods. CIP is a common abbreviation in the professional world and stands for Cleaning in place.
Under CIP, the skilled artisan understands that hard surfaces of objects, containers, tanks, such as milk or fermentation tanks in breweries usually automatically by locally stored cleaning and / or disinfecting agent via installed on site or in the object to be cleaned devices and devices, such as lines, pumps, nozzles, containers, spray heads, are treated.

Accordingly, CIP purification, as understood by those skilled in the art, is Cleaning and / or disinfecting hard surfaces in a specific Procedure, the CIP procedure. Due to the turbulent movement of the cleaning and the disinfectant solution by pumping, spraying and other operations are agents and solutions that tend to foam, for the CIP process completely unsuitable.

For this reason, in practice, the use of funds that are strong foaming surfactants, such as sulfonic acids or sulfonates, alkylamine oxides, ether carboxylic acids, Contain alkyl ether sulfates, in connection with CIP process basically omitted.

On the other hand, especially in the CIP process, the wetting properties the funds used are essential. This is how germ problems occur CIP disinfection often occurs when, however, sufficiently effective Disinfectants are used, but these due to poor wetting do not get to the surface to be disinfected or not sufficient stick to this surface for a long time. This can have various reasons. On the one hand, it may be that the input and output used for the CIP process Devices are poorly matched or these from others Reasons do not work as desired. Examples are that spray nozzles clogged or the spray pressure generated by the pump is too low or that Means due to misplanned items available to the Spray jet in the way and lead to so-called spray shadow, not on the surface to be disinfected arrives.

In this connection, it should be mentioned that such problems always occur in practice stand up again and the optimally adjusted CIP system rather the exception is. In addition, because of the plant surfaces, which consist of the most diverse Materials such as stainless steel, copper, brass, polyethylene, Polypropylene, polyvinyl chloride, polyacrylate, polycarbonate and sealing materials such as EPDM (ethylene diamine), NBR (nitrile copper), silicone, Viton, Teflon, etc., a sufficiently long uniform full surface wetting the material surfaces is difficult to realize.

Further difficulties with wetting are caused by the CIP process Complexity of the construction of large-scale production plants to manufacture various foods in the dairy industry, cheese industry, ice-cream production, Beverage industry, meat industry and confectionery industry, which is why structurally conditioned areas are present that are difficult to achieve with the means. Complete wetting with the necessary application concentration - while maintaining a minimum contact time - with selected disinfectants is for safely killing all harmful microorganisms in the previously purified Installations absolutely necessary.

Another disadvantage of common aqueous disinfectant solutions for CIP processes is also that they due to their poor wetting properties are unable to penetrate into microscopically small gaps, surfaces, Scratches and imperfect corners and edges of stainless steel equipment areas to get rid of harmful microorganisms completely.

On the other hand, it is known that surfactant surfactants are capable of this Balance disadvantage. But it is also known that many surfactants due to their strong net effect a very strong foaming behavior under application conditions demonstrate. Foaming disinfectant solutions can be Do not use in the area of CIP systems for disinfection of closed circuits. Strong foaming would be the technical function of these plants and lead to unwanted malfunctions. Therefore waived the expert in particular when using percarboxylic acid-containing agents in CIP process on surfactant components.

Surfactants which work low foams in the CIP range are, for example, substances such as fatty alcohol ethoxylates and propoxylates. These substance classes prohibit in the application, as they are beyond the mechanism of the cloud point only at elevated (> 30 ° C) temperatures low in foam. Since the according to present invention to be considered percarboxylic acids, preferably cold (5 ° C to 30 ° C), the mechanism of these surfactants can not be used. Other tested surfactants, which are good even in the cold Low foaming, have the disadvantage that they are due to the strong oxidizing power of Disinfectants (percarboxylic acid) are destroyed, or that they themselves destroy the disinfectant. Contrary to the prejudices of the professional world were nevertheless within the scope of the present invention experiments for CIP disinfection carried out with oxidation-stable foaming surfactants. It turned out that these are already capable of an extremely low concentration range, the surface tension of the application solution of the used To disinfect disinfectant so that a complete wetting hard-to-wet polymer materials and rubber seals such as Scratches and cracks on metal surfaces is ensured.

a) den Persäuren oder Salzen von Persäuren mit der allgemeinen Formel I R²-O₂C-(CH₂)_x-CO₃H worin R² Wasserstoff oder eine Alkylgruppe von 1 bis 4
Kohlenstoffatomen und x eine Zahl von 1 bis 4 ist, und/oder

b) den Phthalimido-Percarbonsäuren (II), worin der Percarbonsäure-Anteil 1 bis 18 Kohlenstoffatome enthält, und/oder

c) den Verbindungen der Formel III R¹- CO₃H    worin R¹ eine Alkyl- oder Alkenylgruppe mit 1 bis 18 Kohlenstoffatomen ist, zur Desinfektion im CIP-Verfahren.

The present invention accordingly provides the use of an agent containing surfactant components selected from sulfonic acids or sulfonates, alkylamine oxides, ether carboxylic acids and alkyl ether sulfates in a total amount of 0.01 to 1 wt .-%, preferably 0.05 to 0.5 wt .-%, based on the total agent, and one or more percarboxylic acids selected from

a) the peracids or salts of peracids having the general formula I. R ^{2 is} -O ₂ C- (CH ₂ ) _x -CO ₃ H wherein R ^{2 is} hydrogen or an alkyl group of 1 to 4
Carbon atoms and x is a number from 1 to 4, and / or

b) the phthalimido-percarboxylic acids (II), wherein the percarboxylic acid portion contains 1 to 18 carbon atoms, and / or

c) the compounds of the formula III R ¹ - CO ₃ H wherein R ^{1 is} an alkyl or alkenyl group having 1 to 18 carbon atoms, for disinfection in the CIP process.

Preferably, the agent to be used according to the invention contains sulfonic acids or sulfonates which are selected from xylene, octyl, naphthyl and alkylbenzenesulfonic acids or sulfonates, in which case the alkyl group contains between 6 and 16 carbon atoms.
It is very particularly preferred that the surfactants used in the agent to be used according to the invention are alkylbenzenesulfonic acids or sulfonates and / or ethercarboxylic acids.
When alkylamine oxides are contained as preferred components in the agent to be used in the present invention, these are preferably selected from the trialkylamine oxides having an alkyl group containing 8 to 20 carbon atoms and two alkyl groups having a smaller number of carbon atoms in the alkyl chain, the two shorter alkyl groups being the same or different it being most particularly preferred that the selected amine oxide (s) include tallow fatty bis (2-hydroxyethyl) amine oxide, oleyl bis (2-hydroxyethyl) amine oxide, coconut bis (2-hydroxyethyl -) - amine oxide, tetradecyldimethyl-amine oxide and / or alkyldimethyl-amine oxide having 12 to 18 carbon atoms in the alkyl chain are.

a) als Persäuren gemäß der allgemeinen Formel I Persäuren enthalten sind, in denen R² Wasserstoff oder eine Methylgruppe ist, und/oder

b) als Persäuren Phthalimido-Persäuren enthalten sind, in denen der Percarbonsäure-Anteil 1 bis 8 Kohlenstoffatome enthält, und/oder

c) als Persäuren gemäß der allgemeinen Formel III Persäuren mit einer Alkyloder Alkenylgruppe mit 1 bis 12 Kohlenstoffatomen enthalten sind.

Dabei ist es besonders bevorzugt, daß in dem erfindungsgemäß zu verwendenden Mittel als Persäuren eine oder mehrere Verbindungen ausgewählt aus Peressigsäure, Perpropionsäure, Peroctansäure, Phthalimidoperhexansäure, Phthalimidoperoctansäure, Persuccinsäure, Persuccinsäuremonomethylester, Perglutar-säure, Perglutarsäuremonomethyl-ester, Peradipinsäure, Peradipin-säuremonomethylester, Perbemsteinsäure, Perbernsteinsäuremonomethylester, enthalten sind.
In einer weiteren bevorzugten Ausführungsform wird das erfindungsgemäß zu verwendende Mittel vor der Anwendung im CIP-Verfahren zu einer Desinfektionslösung verdünnt, die bezogen auf die gesamte Desinfektionslösung 0,05 ppm bis 100 ppm, besonders bevorzugt 0,5 ppm bis 50 ppm der genannten Tenside enthält.
Ebenfalls bevorzugt ist es, daß das erfindungsgemäß zu verwendende Mittel vor der Anwendung im CIP-Verfahren zu einer Desinfektionslösung verdünnt wird, die bezogen auf die gesamte Desinfektionslösung 10 ppm bis 2000 ppm, vorzugsweise 50 ppm bis 1000 ppm der genannten Percarbonsäuren enthält.Preferably, in the agent to be used according to the invention, the one or more mentioned percarboxylic acids make up a total of 1 to 40% by weight, particularly preferably 2.5 to 15% by weight, based on the total agent. It is also preferred that

a) as peracids according to the general formula I peracids are contained, in which R ^{2 is} hydrogen or a methyl group, and / or

b) as peracids phthalimido peracids are contained, in which the percarboxylic acid portion contains 1 to 8 carbon atoms, and / or

c) peracids according to the general formula III containing peracids having an alkyl or alkenyl group having 1 to 12 carbon atoms.

It is particularly preferred that one or more compounds selected from peracetic acid, perpropionic acid, peroctanoic acid, phthalimidoperoic acid, phthalimidoperoctanoic acid, persuccinic acid, monomethacrylate, perglutaric acid, perglutaric acid monomethyl ester, peradipic acid, peradipic acid monomethyl ester, Perbemsteinsäure in the present invention to be used as peracids , Perbernsteinsäuremonomethylester included.
In a further preferred embodiment, the agent to be used according to the invention is diluted prior to use in the CIP process to a disinfecting solution containing based on the total disinfectant solution 0.05 ppm to 100 ppm, more preferably 0.5 ppm to 50 ppm of said surfactants ,
It is likewise preferred that the agent to be used according to the invention is diluted before use in the CIP process to a disinfecting solution containing 10 ppm to 2000 ppm, preferably 50 ppm to 1000 ppm of said percarboxylic acids based on the total disinfectant solution.

Preferably, the agents to be used according to the invention or their diluted solutions for CIP disinfection in the food, pharmaceutical or cosmetics industry.

a) in einem früheren Schritt die Anlage bei Bedarf durch alkalische und/oder saure Mittel gereinigt wird, danach

b) gegebenenfalls die Oberflächen der Anlage mit Wasser abgespült werden, und anschließend

c) ein erfindungsgemäß zu verwendendes Mittel oder dessen erfindungsgemäß erhältliche mit Wasser verdünnte Lösung manuell oder in einem automatischen System in der Anlage umgepumpt, und/oder versprüht wird, wobei die Einsatztemperaturen zwischen 0 und 50 °C, vorzugsweise zwischen 0 und 30 °C und die Umpump- bzw. Sprühzeiten zwischen 1 und 120 Minuten, vorzugsweise zwischen 5 und 60 Minuten liegen und die Anlage gewünschtenfalls nach erfolgter Behandlung mit Wasser von Trinkwasserqualität gespült wird.

Another object of the present invention is a method for cleaning and / or disinfecting plants, in which

a) in an earlier step, the plant is cleaned if necessary by alkaline and / or acidic means, thereafter

b) if necessary, the surfaces of the system are rinsed with water, and then

c) an agent to be used according to the invention or its water-dilute solution obtainable in accordance with the invention is pumped and / or sprayed manually or in an automatic system, the temperatures of use being between 0 and 50 ° C, preferably between 0 and 30 ° C and the pumping or spraying times are between 1 and 120 minutes, preferably between 5 and 60 minutes and, if desired, the plant is rinsed with drinking water quality after the treatment has been carried out.

Preferably, the agents to be used according to the invention contain additional Components with complexing properties.

Suitable phosphonic acids are, for example, 1-hydroxyethane-1,1-diphosphonic acid, diethylenetriaminepentamethylenephosphonic acid or ethylenediamine tetramethylenephosphonic acid and, in each case, their alkali metal salts.
Preferred application forms of the agents to be used according to the invention are aqueous solutions, gel, emulsion or paste.

Examples

In a first series of experiments, the antimicrobial effect was surfactant as well corresponding surfactant-free peracetic acid disinfecting solutions Saccharomyces cerivisiae var. Diastaticus examined.

To prepare the peracetic acid disinfecting solutions, the agents V1 and E1 with water to a concentration of 0.5% by weight and 1% by weight, respectively adjusted to the entire solution.

Said comparison means V1 and the agent E1 to be used according to the invention are contained in Table 1. It should be noted that the preparation of E1 and V1 was carried out so that in the agent to be used in both cases about 4.5 wt .-% peracetic acid, based on the total agent, were present. Means for microbiological examination (composition in% by weight) raw material E1 V1 acetic acid 20 20 hydrogen peroxide 28 28 hydroxyethane 0.6 0.6 sulfuric acid 1 1 Ether carboxylic acid surfactant 0.35 0 Alkylbenzenesulfonic acid (C10-C13) 0.4 0 Balance to 100% by weight: water

The results in the quantitative suspension test can be seen from Table 2. Results on the fungicidal effectiveness at 20 ° C after different reaction times by specifying the reduction factors (RF) medium Concentration (% by weight) Saccharomyces cerevisiae DSM 70487 (K 5034) inoculum 6.4x10 ⁷ per mL RF (1 minute) RF (5 minutes) E1 0.5 2.12 > 3.52 1 > 3.74 > 3.52 V1 0.5 1.4 > 3.52 1 2.09 > 3.52

From the tabulated results it can be seen that the surfactant-containing 1% peracetic acid disinfectant solutions E1 reached the full effect much faster, namely within 1 minute, while the surfactant-free 1% peracetic acid disinfectant solution after 1 minute only a reduction factor of 2, 09 reached.
As a result, even very small amounts of surfactant are sufficient to achieve a significant improvement in antimicrobial efficacy.

In a second series of experiments, the foam behavior of 0.5 wt .-% or 1.0 wt .-% containing peracetic acid disinfectant solutions of E1 and V1 im Standard foam test investigated.

1. Apparatur

• Zylindrischer Körper mit Temperiermantel, verbunden mit einem Thermostat
• Mess-Skala (0 cm bis 30 cm)
• Kreiselpumpe
• Thermostat (-10°C bis 110°C)

2. Reagenzien

• Prüflösung
• Testverschmutzung (10 gew.-%ige Malzextrakt-Würze)
• destilliertes Wasser (0 Grad Deutsche Härte (0°dH))

3. Durchführung/Arbeitsablauf

Here, a method for determining the foam behavior of cleaning and disinfecting agents in the CIP circuit was chosen. In this method, foam is generated by means of a recirculation process and recorded metrologically.
In particular, several points have to be considered or prepared for carrying out the method:

1st apparatus

• Cylindrical body with tempering jacket, connected to a thermostat
• Measuring scale (0 cm to 30 cm)
• rotary pump
• Thermostat (-10 ° C to 110 ° C)

2. Reagents

• Test solution
• Test contamination (10% by weight malt extract seasoning)
• distilled water (0 degrees German hardness (0 ° dH))

3. Implementation / Workflow

3.1. Testing a pure application solution

2000 g of 0.5% strength by weight and 1.0% strength by weight peracetic acid disinfectant solutions of E1 and V1 are prepared.
The foam test apparatus is rinsed with 500 mL of the respective solution (circulated for 5 minutes).
The apparatus is then filled with the solution up to a height of 2.5 cm (measuring scale) and brought to a test temperature of 5 ° C.
Thereafter, the solution is circulated at a flow rate of 115 L / h. The resulting foam is read after 10 minutes of circulation on the measuring scale (foam height in cm).
After switching off the pump, the foam decay rate is determined based on the foam height after 1, 3 and 5 minutes.

3.2. Testing the solution under contamination

• Addition to 500 mL solution: 100 mL test soil Testing as in 3.1. specified.
• Add another 100 mL of test soil after the test.
  Repeated test according to 3.1.

The results with the tested 0.5% by weight and 1.0% by weight, respectively, containing peracetic acid disinfecting solutions of E1 and V1 are shown in Table 3. Foam height in mL in the standard foam test at 5 ° C without and with addition of test contamination medium Concentration (% by weight) Foam height at different levels of test contamination (T1) 0 mL T1 100 mL T1 200 mL T1 E1 0.5 0 1 5 1 0 2 8th V1 0.5 0 1 3 1 0 1 5

From the tabulated results it can be seen that when limited to the mentioned surfactant levels in E1, the CIP process not by unwanted Foam is impaired.

In a further series of experiments, the wetting behavior was 0.1% by weight, Containing 0.5 wt .-% and 1.0 wt .-% peracetic acid disinfecting solutions examined by E1 and V1.

For this purpose, the correspondingly diluted solutions of E1 or V1 were prepared in 250 ml beakers.
Subsequently, previously degreased stainless steel sheets were immersed in these solutions. In the next step, the sheets were removed from the solutions with tweezers. The remaining solution is allowed to drain for 10 seconds. Thereafter, the extent of surface wetting was visually estimated.
It was found that at all three concentrations of E1, the degreased stainless steel sheets were wetted to about 95%.

On the other hand, those treated with different concentrations of V1 showed degreased stainless steel sheets in all cases a wetting of only about 10%.

It can be seen that even at very low surfactant concentrations in E1 comprehensible advantages with regard to wetting against tensi-free agents available.

Claims (10)

1. Use of an agent, said agent including surfactant components selected from sulfonic acids or sulfonates, alkylamine oxides, ether carboxylic acids and alkylether sulfates in an amount totaling 0.01 to 1 wt.-%, preferably 0.05 to 0.5 wt.-%, relative to the overall agent, as well as one or more percarboxylic acids selected from

   a) peracids or salts of peracids having the general formula I R²-O₂C-(CH₂)_x-CO₃H    wherein R² is hydrogen or an alkyl group having 1 to 4 carbon atoms, and x is a number of from 1 to 4, and/or

   b) phthalimido-percarboxylic acids (II), in which the percarboxylic acid portion includes 1 to 18 carbon atoms, and/or

   c) compounds of formula III R¹-CO₃H    wherein R¹ is an alkyl or alkenyl group with 1 to 18 carbon atoms, for disinfection in a CIP process.
2. The use according to claim 1, characterized in that the above-mentioned agents include sulfonic acids or sulfonates selected from xylene-, octyl-, naphthyl- and alkylbenzenesulfonic acids or -sulfonates, the alkyl group in the latter case including between 6 and 16 carbon atoms.
3. The use according to any of claims 1 or 2, characterized in that the agent to be used includes alkylbenzenesulfonic acids or -sulfonates and/or ether carboxylic acids as surfactants.
4. The use according to one or more of claims 1 to 3, characterized in that said one or more percarboxylic acids represent 1 to 40 wt.-%, preferably 2.5 to 15 wt.-%, relative to the overall agent.
5. The use according to one of claims 1 to 4, characterized in that

   a) peracids wherein R² is hydrogen or a methyl group are included as peracids according to general formula I, and/or

   b) phthalimido-peracids wherein the percarboxylic acid portion includes 1 to 8 carbon atoms are included as peracids, and/or

   c) peracids having an alkyl or alkenyl group with 1 to 12 carbon atoms are included as peracids according to general formula III.
6. The use according to claim 5, characterized in that one or more compounds selected from peracetic acid, perpropionic acid, peroctanoic acid, phthalimidoperhexanoic acid, phthalimidoperoctanoic acid, persuccinic acid, persuccinic acid monomethyl ester, perglutaric acid, perglutaric acid monomethyl ester, peradipic acid, peradipic acid monomethyl ester are included as peracids.
7. The use according to one or more of claims 1 to 6, characterized in that the agent is diluted to form a disinfecting solution prior to use in a CIP process, which solution, relative to the overall disinfecting solution, includes 0.05 ppm to 100 ppm, more preferably 0.5 ppm to 50 ppm of the above-mentioned surfactants.
8. The use according to one or more of claims 1 to 7, characterized in that the agent is diluted to form a disinfecting solution prior to use in a CIP process, which solution, relative to the overall disinfecting solution, includes 10 ppm to 2000 ppm, preferably 50 ppm to 1000 ppm of the above-mentioned percarboxylic acids.
9. Use of an agent to be used according to any of claims 1 to 6 or of a solution diluted according to any of claims 7 or 8 for CIP disinfection in the food, pharmaceutical or cosmetic industry.
10. A method of cleaning and/or disinfecting installations, wherein

    a) if required, the installation is cleaned in a foregoing step using alkaline and/or acidic agents, followed by

    b) optional rinsing of the installation surfaces with water, and subsequently

    c) circulating and/or spraying in the installation, by hand or in an automatic system, an agent to be used according to any of claims 1 to 6 or a solution diluted according to any of claims 7 or 8, the temperatures of use being between 0 and 50°C, preferably between 0 and 30°C, the circulating and/or spraying periods ranging between 1 and 120 minutes, preferably between 5 and 60 minutes, and rinsing the installation after completed treatment, using water of potable water quality.