EP1349912A1

EP1349912A1 - Use of low foam percarboxlic acid based products containing surfactants for cip-desinfection

Info

Publication number: EP1349912A1
Application number: EP01271432A
Authority: EP
Inventors: Siegfried Bragulla
Original assignee: Ecolab Inc
Current assignee: Ecolab Inc
Priority date: 2000-12-21
Filing date: 2001-12-12
Publication date: 2003-10-08
Anticipated expiration: 2021-12-12
Also published as: US20040029755A1; EP1349912B1; DE50105496D1; DE10064372A1; WO2002050233A1; ATE290062T1; US7226898B2

Abstract

The invention relates to the use of a product containing surfactant components, selected from sulfonic acids or sulfonates, alkyl aminoxides, ether carboxylic acids and alkyl ether sulfates in a quantity amounting to 0.01 1 wt. %, preferably 0.05 - 0.5wt. % in relation to the total product. According to the invention, the product contains one or more percarboxylic acids selected from a) peracids or the salts of peracids having general formula (I) R<2>-O2C-(CH2)X CO3H, wherein R represents hydrogen or an alkyl group with 1 - 4 carbon atoms and x is a number between 1 - 4, and/or b) phthalimido-percarboxyl acids (II), wherein the proportion of percarboxyl acid corresponds to 1 - 18 carbon atoms, and/or c) compounds of formula (III) R<1>-CO3H, wherein R<1> is an alkyl or an alkenyl group containing 1 - 18 carbon atoms. The inventive product is used for disinfection purposes according to the CIP method.

Description

"Use of low-foam, surfactant-containing percarboxylic acid agents for CIP

Disinfection"

The present invention relates to the use of low-foam, surfactant-containing percarboxylic acid agents for CIP disinfection.

The use of halogen-releasing substances, halogen carboxylic acids such as monobromacetic acid, oxidative compounds such as chlorine dioxide, peracetic acid, active chlorine and other antimicrobial substances such as isothiazolinones for cleaning and / or disinfecting hard surfaces is known.

Furthermore, in KH Wallhäusser "Practice of Sterilization, Disinfection and Preservation", 5th ed. (1995) and from HP Fiedler "Lexicon of auxiliaries for pharmacy, cosmetics and related areas", 3rd ed. (1989) there are numerous antimicrobial effective means such as u. a. oxidative agents, organic acids, phenyl compounds or guanidines and numerous other compounds are also mentioned.

Depending on the formulation chosen, for example in combination with foaming surfactants, it may be that such active ingredients in the cleaning solution promote the formation of foam, which is not desirable, for example, in some of the fields of application of the food-producing industry, but also in the pharmaceutical or cosmetic industry, etc. ,

In particular in the CIP cleaning process, there is a need for agents which, when used, do not disturb the foaming behavior and at the same time achieve particularly good wetting of the surfaces to be treated.

Accordingly, the problem addressed by the present invention was to look for simple means which, when used in disinfection using the ClP method, would achieve a very good disinfection result and, at the same time, wetting properties are positively influenced, without a foaming behavior which would be objectionable for the ClP process being observed.

Before the solution to the problem is discussed below, it must be explained what the present invention understands by the ClP method. CIP is an abbreviation commonly used in the professional world and stands for cleaning in place. The person skilled in the art understands by CIP that hard surfaces of objects, containers, tanks, such as milk or fermentation tanks in breweries, usually automatically by means of cleaning agents and / or disinfectants stored on site, via devices and devices installed on or in the object to be cleaned, such as pipes, pumps, nozzles, containers, spray heads, are treated.

Accordingly, the CIP cleaning, as the person skilled in the art understands, is the cleaning and / or disinfection of hard surfaces in a specific process, the ClP process. Due to the turbulent movement of the cleaning and disinfecting solution by pumping, spraying and other processes, agents and solutions that tend to foam are completely unsuitable for the ClP process.

For this reason, the use of agents which contain strongly foaming surfactants, such as sulfonic acids or sulfonates, alkylamine oxides, ether carboxylic acids, alkyl ether sulfates, is generally not used in connection with the ClP process.

On the other hand, the wetting properties of the agents used are particularly important in the ClP process. Germ problems in CIP disinfection processes often occur when sufficiently effective disinfectants are used, but because of poor wetting they do not reach the surface to be disinfected or do not adhere to this surface for a sufficiently long time. This can have various reasons. On the one hand, it is possible that the devices and devices used for the ClP process are poorly matched to one another, or these are from others Reasons do not work as desired. Examples are that spray nozzles are clogged or the spray pressure generated by the pump is too low or the agent does not reach the surface to be disinfected due to objects which are present due to incorrect planning and which stand in the way of the spray jet and lead to so-called spray shadows.

In this context it should be mentioned that such problems occur again and again in practice and the optimally set CIP system is rather the exception. In addition, due to the system surfaces, which are made from a wide variety of materials such as stainless steel, copper, brass, polyethylene, polypropylene, polyvinyl chloride, polyacrylate, polycarbonate and sealing materials such as EPDM (ethylenediamine), NBR (nitrile budadiene), silicone, Viton, Teflon etc. exist, it is difficult to achieve a sufficiently long, uniform full coverage of the material surfaces.

In the ClP process, the complexity of the design of large-scale production plants for the production of a wide variety of foods in the dairy, cheese, ice cream, beverage, meat and confectionery industries poses further difficulties with regard to wetting, which is why there are areas that can hardly be reached with the agent due to the design. A complete wetting with the necessary application concentration - with observance of a minimum contact time - with selected disinfectants is absolutely necessary for the safe killing of all harmful microorganisms in the previously cleaned plants.

Another disadvantage of common aqueous disinfectant solutions for ClP processes is also that, because of their poor wetting properties, they are unable to get into microscopic gaps, surfaces, scratches and inadequate corners and edges of plant areas made of stainless steel, in order here as well to completely destroy harmful microorganisms. On the other hand, it is known that surface-active surfactants are able to compensate for this disadvantage. However, it is also known that many surfactants show very strong foaming behavior under application conditions due to their strong wetting action. Foaming disinfectant solutions cannot be used in the area of CIP systems for disinfecting closed circuits. Heavy foam formation would impair the technical function of these systems and lead to unwanted malfunctions. For this reason, the person skilled in the art, especially when using percarboxylic acid-containing agents in the ClP process, dispenses with surfactant components.

Surfactants that work with little foam in the CIP area are, for example, substances such as fatty alcohol ethoxylates and propoxylates. These substance classes are forbidden in use because they only become low-foaming at elevated (> 30 ° C) temperatures via the mechanism of the cloud point. Since the percarboxylic acids to be considered according to the present invention are preferably used cold (5 ° C. to 30 ° C.), the mechanism of these surfactants cannot be used. Other tested surfactants, which are already low-foaming even in the cold, have the disadvantage that they are destroyed by the strong oxidizing power of the disinfectant (percarboxylic acid) or that they destroy the disinfectant themselves. Contrary to the prejudices of the experts, attempts were nevertheless made in the context of the present invention for CIP disinfection with oxidation-stable foaming surfactants. It was shown that even in an extremely low concentration range they are capable of reducing the surface tension of the application solution of the disinfectant used in such a way that complete wetting of difficult-to-wet polymer materials and rubber seals as well as scratches and gaps on metal surfaces is ensured.

The present invention accordingly relates to the use of an agent comprising 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% by weight, preferably 0.05 to 0.5% by weight .-%, loading drew on the entire agent, and one or more percarboxylic acids selected from a) the peracids or salts of peracids with the general formula IR ² -O ₂ C- (CH ₂ ) _x -C0 ₃ H (I) wherein R ^{2 is} hydrogen or a Alkyl group of 1 to 4 carbon atoms and x is a number of 1 to 4, and / or b) the phthalimido-percarboxylic acids (II), in which the percarboxylic acid content contains 1 to 18 carbon atoms, and / or c) the compounds of the formula III

R - C0 ₃ H (III), wherein R ^{1 is} an alkyl or alkenyl group with 1 to 18 carbon atoms, for disinfection in the ClP process.

The agent to be used according to the invention preferably contains sulfonic acids or sulfonates selected from xylene, octyl, naphthyl and alkylbenzenesulfonic acids or sulfonates, in the latter case the alkyl group containing between 6 and 16 carbon atoms.

It is very particularly preferred that the agent to be used according to the invention contains alkylbenzenesulfonic acids or sulfonates and / or ether carboxylic acids as surfactants.

If alkylamine oxides are present as preferred components in the agent to be used according to the invention, these are preferably selected from the trialkylamine oxides with an alkyl group containing 8 to 20 carbon atoms and two alkyl groups with a smaller number of carbon atoms in the alkyl chain, the two shorter alkyl groups being the same or different can be, it being very particularly preferred that the amine oxide (s) selected is tallow fat bis (2-hydroxyethyl) amine oxide, oley bis (2-hydroxyethyl) amine oxide, coconut bis (2-hydroxyethyl) -) - Amine oxide, tetradecyldimethylamine oxide and / or alkyldimethylamine oxide which has 12 to 18 carbon atoms in the alkyl chain. In the agent to be used according to the invention, the one or more percarboxylic acids mentioned preferably 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) peracids according to the general formula I are contained, in which R ^{2 is} hydrogen or a methyl group, and / or b) phthalimido peracids are included as peracids, in which the percarboxylic acid content is 1 contains up to 8 carbon atoms, and / or c) peracids according to the general formula III contain peracids with an alkyl or alkenyl group with 1 to 12 carbon atoms.

It is particularly preferred that in the agent to be used according to the invention one or more compounds selected as peracids from peracetic acid, perpropionic acid, peroctanoic acid, phthalimidoperhexanoic acid, phthalimidoperoctanoic acid, persuccinic acid, persuccinic acid monomethyl ester, perglutaric acid, perglutaric acid monomonic acid acid, peradipino acid - Methyl ester, succinic acid, monosuccinic acid monomethyl ester are included.

In a further preferred embodiment, the agent to be used according to the invention is diluted before use in the ClP process to a disinfectant solution which, based on the total disinfectant solution, contains 0.05 ppm to 100 ppm, particularly preferably 0.5 ppm to 50 ppm, of the surfactants mentioned ,

It is also preferred that the agent to be used according to the invention is diluted before use in the ClP process to a disinfectant solution which contains 10 ppm to 2000 ppm, preferably 50 ppm to 1000 ppm, of the percarboxylic acids mentioned, based on the total disinfectant solution.

The agents to be used according to the invention or their diluted solutions for CIP disinfection are preferably used in the food, pharmaceutical or cosmetics industry. Another object of the present invention is a method for cleaning and / or disinfecting systems, in which a) in an earlier step the system is cleaned if necessary by alkaline and / or acidic agents, then b) optionally the surfaces of the system with water are rinsed off, and then c) an agent to be used according to the invention or its solution which is obtainable according to the invention and diluted with water is pumped around in the system manually or in an automatic system, and / or sprayed, the operating temperatures 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 system is rinsed with water of drinking water quality after the treatment.

The agents to be used according to the invention preferably contain additional components with complex-forming properties.

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

Examples

In a first test series, the antimicrobial effect of surfactant-containing and corresponding surfactant-free peracetic acid disinfectant solutions against Saccharomyces cerivisiae var. Diastaticus was investigated.

To prepare the peracetic acid disinfectant solutions, agents V1 and E1 were adjusted with water to a concentration of 0.5% by weight and 1% by weight, based on the total solution.

The comparison means V1 mentioned and the agent E1 to be used according to the invention are contained in Table 1. It should be noted that the production of E1 and V1 was carried out in such a way that the agent to be used in both cases had about 4.5% by weight of peracetic acid, based on the total agent.

Table 1: Means for microbiological analysis (composition in% by weight)

The results in the quantitative suspension test can be found in Table 2. Table 2:

Results on fungicidal activity at 20 ° C after different exposure times by specifying the reduction factors (RF)

It can be seen from the tabulated results that the surfactant-containing 1% peracetic acid disinfectant solution E1 achieved its full effect much faster, namely within 1 minute, while the surfactant-free 1% peracetic acid disinfectant solution only achieved a reduction factor of 2 after 1 minute. 09 reached.

As a result, very small amounts of surfactant are sufficient to achieve a significant improvement in the antimicrobial activity.

In a second test series, the foam behavior of peracetic acid disinfectant solutions of E1 and V1 containing 0.5% by weight and 1.0% by weight was examined in a standard foam test.

A method was chosen to determine the foaming behavior of cleaning and disinfectants in the CIP cycle. In this method, foam is generated by means of a pumping process and recorded by measurement. In particular, several points must be observed or prepared for the implementation of the method: 1. Apparatus

• Cylindrical body with temperature jacket, connected to a thermostat

• Measuring scale (0 cm to 30 cm)

• centrifugal pump

• Thermostat (-10 ° C to 110 ° C)

2. Reagents

• Test solution

• test soiling (10% by weight malt extract wort)

• distilled water (0 degrees German hardness (0 ° dH))

3. Execution / workflow

3.1. Testing a pure application solution

2000 g of 0.5% by weight and 1.0% by weight peracetic acid disinfectant solutions of E1 and V1 are produced.

The foam test apparatus is rinsed with 500 mL of the respective solution (circulate for 5 minutes).

The apparatus is then filled to a height of 2.5 cm (measuring scale) with the solution and brought to a test temperature of 5 ° C. The solution is then circulated at a flow rate of 115L / h. The resulting foam is read off on the measuring scale after 10 minutes of circulation (foam height in cm). After the pump is switched off, the foam disintegration rate is determined based on the foam height after 1, 3 and 5 minutes.

3.2. Examination of the solution under contamination

Addition to 500 mL solution: 100 mL test dirt. Check as in 3.1. specified.

• Add a further 100 mL test dirt after the test. Repeated test according to 3.1. The results with the tested peracetic acid disinfectant solutions of E1 and V1 containing 0.5% by weight and 1.0% by weight are shown in Table 3.

Table 3: Foam height in mL in the standard foam test at 5 ° C without and with the addition of test soiling

It can be seen from the tabulated results that, when limited to the amounts of surfactant mentioned in E1, the ClP process is not adversely affected by undesired foam generation.

In a further test series, the wetting behavior of peracetic acid disinfectant solutions of E1 and V1 containing 0.1% by weight, 0.5% by weight or 1.0% by weight was investigated.

For this, the correspondingly diluted solutions of E1 and V1 were prepared in 250 mL beakers.

Subsequently, degreased stainless steel sheets were immersed in these solutions. In the next step, the sheets were removed from the solutions using tweezers. The remaining solution is allowed to drain for 10 seconds. The extent of surface wetting was then assessed visually. It was found that at all three concentrations of E1 the degreased stainless steel sheets were wetted to about 95%. On the other hand, the degreased stainless steel sheets treated with different concentrations of V1 showed a wetting of only about 10% in all cases.

From this it can be seen that even at very low surfactant concentrations in E1 there are clear advantages with regard to wetting compared to surfactant-free agents.

Claims

Patent claims

1. 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% by weight, preferably 0.05 to 0.5% by weight on the entire agent, and one or more percarboxylic acids selected from a) the peracids or salts of peracids with the general formula I.

R ² -0 ₂ C- (CH ₂ ) _x -CO ₃ H (I) wherein R ^{2 is} hydrogen or an alkyl group of 1 to 4 carbon atoms and x is a number of 1 to 4, and / or b) the phthalimido-percarboxylic acids (II), in which the percarboxylic acid component contains 1 to 18 carbon atoms, and / or c) the compounds of the formula III

R ¹ - CO ₃ H (III) wherein R ^{1 is} an alkyl or alkenyl group with 1 to 18 carbon atoms, for disinfection in the ClP process.

2. Use according to claim 1, characterized in that the said agents contain sulfonic acids or sulfonates which are selected from xylene, octyl, naphthyl and alkylbenzenesulfonic acids or sulfonates, the alkyl group in the latter case containing between 6 and 16 carbon atoms.

3. Use according to one of claims 1 or 2, characterized in that alkylbenzenesulfonic acids or sulfonates and / or ether carboxylic acids are contained in the agent to be used as surfactants.

4. Use according to one or more of claims 1 to 3, characterized in that the one or more percarboxylic acids make up a total of 1 to 40 wt .-%, preferably 2.5 to 15 wt .-%, based on the total agent.

5. Use according to one of claims 1 to 4, characterized in that a) peracids according to the general formula I are included, in which R ^{2 is} hydrogen or a methyl group, and / or b) phthalimido-peracids are contained as peracids , in which the percarboxylic acid component contains 1 to 8 carbon atoms, and / or c) peracids according to the general formula III contain peracids with an alkyl or alkenyl group with 1 to 12 carbon atoms.

6. Use according to claim 5, characterized in that the peracids are one or more compounds selected from peracetic acid, perpropionic acid, peroctanoic acid, phthalimidoperhexanoic acid, phthalimidoper-octanoic acid, persuccinic acid, persuccinic acid monomethyl ester, perglutaric acid, perglutaric acid methyl ester, peradipic acid, peradipic acid, peradipic acid , Succinic acid, monosuccinic acid monomethyl ester, are included.

7. Use according to any one of claims 1 to 6, characterized in that the agent is diluted to a disinfectant solution prior to use in the ClP process, which based on the total disinfectant solution 0.05 ppm to 100 ppm, preferably 0.5 ppm to Contains 50 ppm of the surfactants mentioned.

8. Use according to one of claims 1 to 7, characterized in that the agent is diluted before use in the ClP process to a disinfectant solution, which is 10 ppm to 2000 ppm, preferably 50 ppm to 1000 ppm, based on the total disinfectant solution Contains percarboxylic acids.

9. Use of agents to be used according to one of claims 1 to 6 or the solution diluted according to one of claims 7 or 8 for CIP disinfection in the food, pharmaceutical or cosmetics industry.

0. A method for cleaning and / or disinfecting systems, in which a) in an earlier step the system is cleaned if necessary by alkaline and / or acidic agents, thereafter b) if necessary, the surfaces of the system are rinsed with water, and then c ) an agent to be used in accordance with one of claims 1 to 6 or the solution diluted in accordance with one of claims 7 or 8 is pumped around and / or sprayed in the system manually or in an automatic system, the operating temperatures being between 0 and 50 ° C, preferably between 0 and 30 ° C and the pumping or spraying times between 1 and 120 minutes, preferably between 5 and 60 minutes and the system is rinsed with water of drinking water quality if desired after treatment.