EP2886635B1 - Disinfectant - Google Patents

Description

The invention relates to a disinfectant containing peracetic acid, a kit for producing such a disinfectant, the use of such a disinfectant for disinfecting surfaces, preferably plastic surfaces, and a method for disinfecting plastic containers using the disinfectant.

Drinks are often bottled in plastic bottles. In particular, microbiologically sensitive drinks, such as fruit juices, which are CO2-free or poor, require a so-called cold aseptic filling to ensure a long shelf life, possibly even without cooling. There is a sterilization of product (e.g., fruit juice), container (bottle) and caps, and a combination of the three components under germ-free conditions.

In plastic bottles, especially PET bottles, a common form of sterilization is the so-called wet sterilization using peracetic acid. The inner and outer surfaces of the bottles are sprayed with an aqueous solution of peracetic acid, optionally with steam as the carrier medium.

For effective disinfection, complete wetting of the surfaces is important so a wetting agent is added to the disinfecting solution.

WO 2011/005270 A1 discloses a disinfecting composition containing peracetic acid, a surfactant (phosphate ester) and a water-soluble polymer. WO 2006/076334 A1 discloses as microbiocidal agent a composition of surfactants, peroxides, and polymers containing PVP or PVA. DE 10 2010 038 340 A1 discloses cleaners containing surfactants, peroxy compounds and polymers.

The present invention is based on the object to provide a disinfectant of the type mentioned, which has good wetting properties and is unproblematic usable in the food industry.

This object is achieved by the features of the independent claims. Advantageous embodiments of the invention are disclosed in the dependent claims.

The invention is based on the surprising finding that a peracetic acid-containing disinfectant comprising as wetting agent at least one polymer having cationic dissociable groups or a combination of cationic and anionic dissociable groups, on the one hand causes good wetting of hydrophobic plastic surfaces with the disinfectant of the invention and on the other hand does not contain any ingredients that are questionable in terms of food law or that may require declaration. The polymers defined above as wetting agents cause complete wetting even very hydrophobic surfaces, for example of PET bottles and thus a complete disinfection by the action of peracetic acid on the entire surface. The disinfectant according to the invention can be rinsed without any problems and is largely residue-free and contains no ingredients which, as minimum residues possibly remaining in the bottle, are food-grade questionable.

In the context of the invention, the term disinfectant refers to the actual application solution which is brought into contact with the surfaces to be disinfected. As a rule, such a disinfectant is prepared in situ from at least two components, of which the first component contains peracetic acid and the second component contains a corresponding polymer. The preparation of the disinfectant shortly before use can be done by mixing and usually diluting the components with water prior to spraying on the surfaces, where appropriate, the mixing can be done on the surfaces themselves by separate spraying of the two components. A kit of at least two components described for the production of a disinfectant according to the invention is thus likewise an object of the invention.

Surfactants are used as wetting agents in the prior art. The disinfectant according to the invention surprisingly also causes good wetting without any surfactants. The disinfectants according to the invention are surfactant-free. Surfactants are compounds which lower the interfacial tension, ie amphiphilic compounds having at least one hydrophobic and one hydrophilic moiety. In the context of the invention, the term surfactants denotes the group consisting of anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants and block copolymers (especially from ethylene oxide and propylene oxide units). For an explanation of these classes of surfactants, reference is made by way of example Römpp Chemielexikon, 10th edition, Georg Thieme Verlag, keyword "surfactants ".

The disinfectant according to the invention contains as wetting agent at least one polymer which has cationic dissociable groups or a combination of cationic and anionic dissociable groups. As polymers are called macromolecular compounds constructed from low molecular weight monomer units. For example, reference is made Römpp Chemielexikon, 10th edition, Georg Thieme Verlag, keyword "polymers ".

Ionically dissociable groups dissociate in sufficiently polar solvents (eg, water) to ions and counterions. Accordingly, the at least one polymer in the ready-to-use diluted disinfectant in aqueous solution is at least partially in ionic form. In the context of the invention it is sufficient if the at least one polymer has cationic dissociable groups. Preferably, however, the at least one polymer is an ampholytic polymer, i. it has both cationic and anionic dissociable groups.

Preferably, the at least one polymer may comprise at least one monomer unit having at least one cationic dissociable group and / or at least one monomer unit having at least one anionic dissociable group. The at least one polymer may contain at least one monomer unit having at least one carboxyl function.

Preferably, the at least one polymer has an average molecular weight greater than 10,000, preferably greater than 50,000, more preferably greater than 100,000, and / or less than 1,000,000, preferably less than 500,000. Advantageously, the at least one polymer is an acrylate or methacrylate based copolymer. It is preferred that the copolymer comprises as monomer units and / or N-isopropylacrylamide and / or 2-acrylamido-2-methyl-1-propanesulfonic acid.

Cationic and ampholytic polymers, as used in the context of the invention, are known in the art. For example, reference is made to the EP 1 767 554 A1 which discloses an acrylate or methacrylate based ampholytic polymer comprising as monomer units N-isopropylacrylamide and optionally 2-acrylamido-2-methyl-1-propanesulfonic acid. Corresponding polymers are commercially available.

The disinfectant of the invention may contain more than one polymer having cationic dissociable groups or a combination of cationic and anionic dissociable groups. Preferably, the disinfectant contains two polymers with cationic dissociable groups or a combination of cationic and anionic dissociable groups.

It is advantageous if the disinfectant additionally contains at least one polycarboxylate, preferably a polyacrylate, particularly preferably a copolymer of acrylic acid with 2,5-furandione. The list of possible ingredients is not exhaustive. In particular, the disinfectant is usually water, preferably fully desalted water, as a solvent.

Advantageously, the disinfectant at a temperature of 20 ° C, a surface tension> 50 mN / m, preferably> 60 mN / m (measured by the DeNoüy ring-tearing method).

The disinfectant according to the invention preferably contains peracetic acid in a concentration of 1,000 to 5,000 ppm, more preferably 1,500 to 3,500 ppm. These concentration ranges are preferred for effective surface disinfection.

The content of the wetting agent is preferably 0.02-0.5 wt%, more preferably 0.05-0.3 wt%.

The disinfectant according to the invention may contain further ingredients. For example, it may contain at least one acid for adjusting the pH and / or as a complexing agent. The at least one acid may be an organic acid, preferably an α-hydroxy carboxylic acid such as citric acid, tartaric acid, malic acid, lactic acid, etc. Citric acid is particularly preferred. In the context of the invention, the acid can also be used as an indicator to check the complete rinsing of the disinfectant according to the invention. When using citric acid, for example, its remaining residual content can be determined enzymatically in a known manner.

The disinfectant according to the invention is preferably prepared immediately before use, preferably from a kit which is a further subject of the invention. The kit according to the invention is used for producing a disinfectant according to the invention and contains at least two components. According to the invention, a first component comprises peracetic acid and a second component contains a polymer, which has cationic dissociable groups or a combination of cationic and anionic dissociable groups. The optional further ingredients described above in the context of the disinfectant are preferably included in the second component (wetting agent).

The second component (wetting agent or wetting agent concentrate) preferably has a proportion of polymers with cationic dissociable groups or a combination of cationic and anionic dissociable groups of at least 0.001% by weight, preferably at least 0.01% by weight, more preferably at least 0 , 1 wt .-%, more preferably at least 1 wt .-%, more preferably at least 2 wt .-%, particularly preferably at least 3 wt .-%, and / or at most 40 wt .-%, preferably at most 30 wt. %, more preferably at most 20 wt .-%, more preferably at most 10 wt .-%, particularly preferably at most 5 wt .-% to.

Preferably, this second component contains at least one of the above-described acids, such as, for example, citric acid, preferably 0.5 to 30% by weight of acid. Particularly preferred are 5 to 20 wt .-% acid.

The invention further relates to the use of a disinfectant or kit according to the invention for the disinfection of surfaces, preferably plastic surfaces. Even without the addition of surfactants, complete wetting of hydrophobic plastic surfaces and correspondingly complete surface disinfection takes place.

Another object of the invention is a method for disinfecting plastic containers, in particular plastic bottles. Preferred plastics are PET, PE and polycarbonates. According to the invention, the surfaces of the bottles to be disinfected (outer surfaces and in particular inner surfaces) are brought into contact with a disinfectant according to the invention. This can be done by spraying, optionally spraying using an auxiliary medium such as steam. In the context of the invention, it is likewise possible to spray the components of a kit according to the invention separately (optionally diluted with water) so that the disinfectant according to the invention is formed in situ on the surfaces to be disinfected. Alternatively, and usually preferred, a prior mixing of the components takes place.

The method according to the invention can preferably be used in connection with the cold-sterile filling of beverages, in particular CO2-free or low-energy beverages such as, for example, fruit juices. Preferably, the process can be used at temperatures of 30-60 ° C, more preferably 35-45 ° C.

Embodiments of the invention are described below with reference to the examples.

example 1

The disinfectant according to the invention is preferably produced from a 2-component system or kit. Peracetic acid is contained in the first component and the wetting agent according to the invention in the second component. Peracetic acid component (PES component):
Commercially available aqueous peracetic acid solutions can be used here. In the exemplary embodiments, this is commercially available from Fa. Weigert available concentrate neoseptal® PE 15 used, which contains acetic acid and hydrogen peroxide in aqueous solution, so that an equilibrium with an effective concentration of peracetic acid of about 15 wt .-% sets.

Wetting agent component (NM component invention):

Three wetting agent components according to the invention are prepared according to the following recipes. All percentages in the examples are wt% unless otherwise specified. In the examples below, the wetting agent component according to Example 1.1 is used, unless stated otherwise, and designated as NMK 1. Example 1.1 Amount used (in%) CAS-No. 1-propanaminium, N, N, N-trimethyl-3 - [(2-methyl-1-oxo-2-propenyl) amino] -, chloride, polymer with ethyl 2-propenoate and sodium 2-propenoate 2.6 192003-74-0 2-propenoic acid, polymer with 2,5-furandione, sodium salt 0.4 52255-49-9 citric acid 10 5949-29-1 water ad. 100 Example 1.2 1-propanaminium, N, N, N-trimethyl-3 - ((2-methyl-1-oxo-2-propen-1-yl) amino) -, chloride, polymer with N- (1-methylethyl) -2- propenamides, 2-methyl-2 - ((1-oxo-2-propen-1-yl) amino) -1-propanesulfonic acid and 2-propenoic acid, sodium salt 5.2 880345-00-6 Aziridines, polymer with 2- (chloromethyl) oxiranes and oxiranes, N- (2-carboxyethyl) derivs. 0.4 845752-17-2 citric acid 10 5949-29-1 water ad. 100 Example 1.3 1-propanaminium, N, N, N-trimethyl-3 - [(2-methyl-1-oxo-2-propenyl) amino] -, chloride, polymer with ethyl 2-propenoate and sodium 2-propenoate 5.5 192003-74-0 citric acid 10 5949-29-1 water ad. 100

Wetting agent component (NM component comparative example):

In the comparative examples, as wetting agent component of the prior art doscan® CAF from the company Dr. med. Weigert used. It is a surfactant-containing wetting agent that contains small amounts of QAV (quaternary ammonium compounds). The essential ingredients are fatty alcohol polyglycol ethers and dioctylmethylammonium chloride. Hereinafter, it will be referred to as NMK V.

Example 2

• Beispiel 2.1: 0,08 Gew.-% NMK 1
• Vergleichsbeispiel 2.2: 0,08 Gew.-% NMK V
• Vergleichsbeispiel 2.3: Kein Netzmittel

In this example, the influence of the wetting agent component on the stability of peracetic acid in aqueous solution is examined. Aqueous solutions of the PES component are prepared which have a measured starting concentration of peracetic acid of 1589 ppm. In addition, these solutions contain the following wetting agents:

• Example 2.1: 0.08 wt .-% NMK 1
• Comparative Example 2.2: 0.08 wt .-% NMK V
• Comparative Example 2.3: No wetting agent

The solutions are stirred in a beaker at 40 ° C with a magnetic stirrer. After 8 and 30 h, the concentration of peracetic acid is determined. The concentration data in Table 1 are given in ppm. Table 1 Time Ex. 2.1 Vglbspl. 2.2 Vglbspl. 2.3 0 h 1589 1589 1589 8 h 1587 1600 1598 30 h 1387 1455 1568

It can be seen that, in the absence of a wetting agent, virtually no degradation of the peracetic acid takes place, while both the wetting agent according to the invention and the comparative example of the prior art lead to a slight degradation, which is approximately equal within the measurement inaccuracies.

Example 3

• Beispiel 3.1: 0,1 Gew.-% NMK 1
• Vergleichsbeispiel 3.2: 0,1 Gew.-% NMK V
• Vergleichsbeispiel 3.3: Kein Netzmittel

In this example, the flushability is checked. In Hamburg city water solutions of 1.5 wt .-% PES component are prepared, which contain as wetting agents:

• Example 3.1: 0.1% by weight NMK 1
• Comparative Example 3.2: 0.1% by weight NMK V
• Comparative Example 3.3: No wetting agent

The inner walls of a 1 l PET bottle are wetted with the solutions, the solutions are allowed to drain. The wetting pattern of Example 3.1 and Comparative Example 3.2 shows a frothy full-coverage film that barely ruptures. In Comparative Example 3.3 show individual adherent drops without film formation, ie a poor wetting of the surface.

The wetted bottles were then rinsed 4 times in succession with 30 ml deionized water each. The solution used for rinsing was collected (Lsg 1 to 4) and the surface tension was determined (Table 2, data in [mN / m]). The deionized water used has a surface tension of 72 mN / m. Table 2 Lsg 1 Lsg 2 Lsg 3 Lsg 4 Ex. 3.1 60 63 65 68 Vglbspl. 3.2 44 50 57 60 Vglbspl.3.3 72 72 72 72

It can be seen that a disinfectant according to the invention can be rinsed out significantly better than the comparative example which contains surfactants. According to the invention, already after a single rinse, a surface tension has already been reached, for which four-fold rinsing is required in the comparative example with surfactants. In the case of the solution without wetting agent, which is likewise used for comparison, no lowering of the surface tension takes place from the outset.

Example 4

In this example, the solutions of Example 2 are tested for their disinfecting effect. The inner surfaces of a 1 l PET bottle are fogged with 10 μl of a germ suspension (containing a calculated germ number of 106) of the reference germ B. atrophaeus. This is followed by a conventional disinfection in a cold aseptic filling plant and a subsequent determination of the germ count reduction. This amounts to (in log stages) in Example 2.1 and Comparative Example 2.2 each 6.3, in Comparative Example 2.3 (without wetting agent) only 3.3. It can be seen that the wetting agent used according to the invention leads to just as good complete wetting of the surfaces as the prior art, without the need for surfactants.

Claims (15)

1. Disinfectant comprising peracetic acid, characterized in that the disinfectant is surfactant-free and comprises as a wetting agent at least one polymer which has cationic dissociable groups or a combination of cationic and anionic dissociable groups.
2. Disinfectant according to Claim 1, characterized in that the at least one polymer has anionic and cationic dissociable groups.
3. Disinfectant according to either of Claims 1 and 2, characterized in that the at least one polymer comprises at least one monomer unit having at least one cationic dissociable group and/or comprises at least one monomer unit having at least one anionic dissociable group.
4. Disinfectant according to Claim 3, characterized in that the at least one polymer comprises at least one monomer unit having at least one carboxyl function.
5. Disinfectant according to any of Claims 1 to 4, characterized in that the at least one polymer is an acrylate-based or methacrylate-based copolymer.
6. Disinfectant according to Claim 5, characterized in that the copolymer comprises as monomer units at least N-isopropylacrylamide and/or 2-acrylamido-2-methyl-1-propanesulfonic acid.
7. Disinfectant according to any of Claims 1 to 6, characterized in that the at least one polymer has an average molecular weight of greater than 10,000, preferably of greater than 50,000, more preferably of greater than 100,000, and/or of less than 1,000,000, preferably of less than 500,000.
8. Disinfectant according to any of Claims 1 to 7, characterized in that it comprises peracetic acid in a concentration of 1000 to 5000 ppm, preferably 1500 to 3500 ppm.
9. Disinfectant according to any of Claims 1 to 8, characterized in that it comprises at least one acid, the at least one acid preferably being an organic acid, more preferably a food acid, very preferably citric acid.
10. Kit for preparing a disinfectant according to any of Claims 1 to 9, the kit comprising at least two components, characterized in that a first component comprises peracetic acid and a second component comprises a polymer which has cationic dissociable groups or a combination of cationic and anionic dissociable groups.
11. Kit according to Claim 10, characterized in that in the second component the fraction of polymers having cationic dissociable groups or a combination of cationic and anionic dissociable groups is at least 0.001 wt%, preferably at least 0.01 wt%, more preferably at least 0.1 wt%, more preferably at least 1 wt%, more preferably at least 2 wt%, very preferably at least 3 wt%, and/or not more than 40 wt%, preferably not more than 30 wt%, more preferably not more than 20 wt%, more preferably not more than 10 wt%, very preferably not more than 5 wt%.
12. Kit according to Claim 10 or 11, characterized in that the second component comprises at least one acid, the at least one acid being preferably an organic acid, more preferably a food acid, very preferably citric acid, the acid content being preferably 0.5 to 30 wt%, more preferably 5 to 20 wt%.
13. Use of a disinfectant according to any of Claims 1 to 9 or of a kit according to any of Claims 10 to 12 for disinfecting surfaces, preferably surfaces of plastic.
14. Method for disinfecting plastic containers, more particularly plastic bottles, characterized in that the bottle surfaces to be disinfected are contacted with a disinfectant according to any of Claims 1 to 9 or with the components of a kit according to any of Claims 10 to 12.
15. Method according to Claim 14, characterized in that the disinfection takes place at a temperature of 30 to 60°C, preferably 35 to 45°C.