BIOCIDAL AGENT

Description

Technical field

[0001] The invention relates to construction chemical products containing a biocidal agent. Furthermore, the invention relates to a method for the production and / or preservation of a construction chemical product. The construction chemical products according to the invention are adhesives. State of the art

[0002] Water-based construction chemicals, such as paints, adhesives, sealants, primers, leveling compounds, fillers, or plasters, can provide a breeding ground for microorganisms like bacteria, yeasts, and fungi. Without special preservation measures, these products can exhibit high microbial counts just a few days after production. To ensure that these products meet hygienic requirements and maintain their shelf life, biocides are typically added to reduce microbial growth.

[0003] Biocides used include those based on isothiazolinone. Specific examples are benzisothiazolinone (BIT), methylisothiazolinone (MIT), and the combination of chloroisothiazolinone with methylisothiazolinone (CIT / MIT).

[0004] WO 2015 / 028414 (Lanxess Deutschland GmbH) describes, for example, biocidal products containing at least one isothiazolinone from the group consisting of 1,2-benzisothiazolin-3-one (BIT) and 2-methyl-4-isothiazolin-3-one (MIT), as well as at least one N-alkyl guanidinium salt. They may also contain 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) and optionally other biocidal substances.

[0005] However, a disadvantage of this solution is that isothiazolinone-based biocides are usually allergenic, and products preserved with such biocides must be labelled with a corresponding GHS label depending on the concentration of the biocides (e.g., EUH statement 208 or, in the case of higher biocide concentrations, H317 statement + exclamation mark).

[0006] Another way to prevent microbial growth, which is used, for example, in water-based interior paints, is to formulate the products to have a high pH value in the range of 11 to 11.4. This creates a hostile environment for all types of microorganisms.

[0007] However, this approach is not suitable for all construction chemical products. For example, adhesives and sealants containing polymers based on acrylic esters (e.g., butyl acrylates, ethylhexyl acrylates) cannot be formulated at such high pH values ​​without technical disadvantages. This is because the ester groups in the polymers hydrolyze under strongly alkaline conditions, drastically reducing their storage stability.

[0008] Therefore, there is still a need for improved solutions that do not have the aforementioned disadvantages, or have them to a lesser extent. Description of the invention

[0009] The object of the invention is therefore to provide a construction chemical product containing a flexibly applicable biocidal agent which is as harmless as possible to humans and the environment and also enables long-term preservation of the construction chemical product.

[0010] It was surprisingly found that the problem can be solved by a construction chemical product containing a biocidal agent according to claim 1. The core of the invention is therefore a construction chemical product containing a biocidal agent comprising bronopol and a pyrithione salt, and additionally containing a compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

[0011] It has been shown that the biocidal agent contained in the construction chemical product according to the invention exhibits a broad spectrum of activity against bacteria, yeasts, and fungi. Furthermore, in the concentration ranges required for the preservation of construction chemical products, the two active ingredients, bronopol and pyrithione salts, are not classified as allergens. Accordingly, construction chemical products can be manufactured that are far less harmful to humans and the environment and do not require any of the otherwise standard hazard labeling.

[0012] This is particularly beneficial for people with isothiazolinone allergies.

[0013] Nevertheless, the biocidal agent in the inventive construction chemical product enables effective and long-term preservation of construction chemical products at moderate pH values ​​of 6–9. Depending on the product, storage stability of up to 12 months or more can be achieved.

[0014] Without being bound to the theory, it is assumed that the bronopol and the pyrithione salt work together functionally, thus achieving high effectiveness and a broad spectrum of activity against a wide variety of microorganisms.

[0015] Furthermore, the biocidal agent can be combined with conventional (allergenic) biocides, such as those found in commercially available aqueous polymer dispersions. This allows the total biocide content to be increased without increasing the proportion of allergenic substances, or the allergenic biocide content to be kept below the relevant limits.

[0016] The biocidal agents are also suitable for preserving various construction chemical products and can therefore be used flexibly.

[0017] Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of dependent claims. Method for implementing the invention

[0018] A first aspect of the present invention relates to a construction chemical product comprising a biocidal agent comprising bronopol and a pyrithione salt and additionally comprising a compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, wherein the construction chemical product is an adhesive, in particular a flooring adhesive, comprising an aqueous polymer dispersion and additionally fillers, with a polymer dispersion content of 35-55 wt.%, and a filler content, in particular sand and / or calcium carbonate, of 25-50 wt.%, wherein all content is based on the total weight of the adhesive.

[0019] Bronopol is a solid at room temperature and is also known as 2-bromo-2-nitro-1,3-propanediol. Pyrithione salts are salts of pyrithione, a solid at room temperature known as pyridine-2-thiol-1-oxide. The pyrithione salt is, in particular, sodium pyrithione and / or zinc pyrithione; sodium pyrithione is especially preferred.

[0020] The weight ratio of bronopol to pyrithione salt is preferably in the range of 30:70 - 70:30, particularly 40:60 - 60:40, and especially 50:50. This ensures optimal efficacy against a wide variety of microorganisms.

[0021] The biocidal agent may also contain at least one representative from the group consisting of surfactants, wetting agents, emulsifiers, dispersants, stabilizers, adhesion promoters, thickeners, spreading agents, organic solvents, water, solid carrier substances, perfumes, dyes and / or pH regulators.

[0022] Advantageously, the biocidal agent in the construction chemical product according to the invention is free of isothiazolinone-based biocides. Specifically, the biocidal agent is free of 1,2-benzisothiazolin-3-one (BIT), 2-methyl-4-isothiazolin-3-one (MIT), and / or 5-chloro-2-methyl-4-isothiazolin-3-one (CIT). In particular, the biocidal agent according to the invention contains none of these three substances.

[0023] Furthermore, the biocide contains an additional compound that degrades 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), particularly cysteine. The use of such a compound can partially or completely degrade any 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) present in a formulation component of the construction chemical product. This allows for the production of construction chemical products that are free of problematic 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) or have an unproblematic content.

[0024] The compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, has a proportion of 1-10 wt.%, in particular 2-5 wt.%, in relation to the content of bronopol and pyrithione salt combined.

[0025] The sum of the weight fractions of bronopol, the pyrithione salt, and the additional compound present which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) is, based on the total weight of the biocidal agent, in particular 5–100 wt.%. Specifically, the fraction is at least 25 wt.%, preferably at least 50 wt.%, and in particular at least 90 wt.%.

[0026] The biocidal agent can either be added by dosing the individual active ingredients to the construction chemical product to be protected, whereby the concentration ratio can be individually adjusted depending on the requirements of the preservation problem to be solved, or a finished biocidal agent containing several or all of the individual active ingredients can be added.

[0027] In particular, the biocidal product is a single-component product. All components of the biocidal product are contained in a single component and / or a single container. This simplifies handling, as the concentration ratios of the individual components are fixed.

[0028] In a particularly advantageous embodiment, the biocidal agent is a two-component agent, wherein preferably the bronopol and the pyrithione salt are in a first component and the compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, is in the second component.

[0029] According to another advantageous embodiment, the biocidal agent is a two- or multi-component agent, with the bronopol preferably being present in a first component and the pyrithione salt in a second component. Furthermore, the compound that degrades 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, is present in a separate third component. Multi-component agents offer particularly flexible application and can be optimally adapted to specific requirements.

[0030] The construction chemical product according to the invention is an adhesive. In particular, it is a flooring adhesive, a tile adhesive, a mounting adhesive, or a wood adhesive.

[0031] The construction chemical product is a water-based product, or a product that contains a proportion of water before processing.

[0032] The construction chemical product contains an aqueous polymer dispersion. The effect of the biocidal agent is particularly pronounced in construction chemical products based on polymer dispersions.

[0033] The aqueous polymer dispersion is, in particular, a dispersion of homo- and / or copolymers of ethylene, propylene, butylene, isoprene, butadiene, acrylic acid, methacrylic acid, acrylates, methacrylates, vinyl esters, vinyl acetate, and / or styrene. Particularly suitable polymers are butadiene / styrene copolymers, acrylic acid / styrene copolymers, methacrylic acid / styrene copolymers, ethylene / vinyl acetate copolymers, vinyl acetate / (meth)acrylic alkyl ester copolymers, styrene / (meth)acrylic alkyl ester copolymers, and / or (meth)acrylic alkyl ester copolymers.

[0034] According to the invention, the proportion of aqueous polymer dispersion, based on the total weight of the construction chemical product, is 35–55 wt.%. The mass fraction of the polymer in the polymer dispersion, based on the weight of the polymer dispersion, is preferably 25–70 wt.%, and more particularly 40–65 wt.%. Furthermore, the construction chemical product contains fillers, in particular sand and / or calcium carbonate, wherein, based on the total weight of the construction chemical product, the proportion of the fillers is in the range of 25–50 wt.%.

[0035] Fillers can be selected from materials such as sand, calcium carbonate, magnesium oxide, zinc oxide, chalk, talc, carbon black, and / or barium sulfate. Sand and / or calcium carbonate are particularly preferred.

[0036] In particular, the fillers have a particle size in the range of < 300 µm, preferably < 200 µm. This is especially the case when the construction chemical product is a flooring adhesive. The particle size refers to the D50 value, and the particle size is determined, in particular, as described in the standard ISO 13320:2020.

[0037] The construction chemical product contains both an aqueous polymer dispersion and fillers.

[0038] The construction chemical product is: An adhesive, in particular a flooring adhesive, comprising a polymer dispersion content of 35-55 wt.%, and a filler content, in particular sand and / or calcium carbonate, of 25-50 wt.%; wherein all proportions are based on the total weight of the adhesive; preferably the particle sizes are < 200 µm.

[0039] In particular, the construction chemical product contains 0.005–0.1 wt%, especially 0.015–0.05 wt%, and specifically 0.02–0.04 wt%, of bronopol, as well as 0.005–0.1 wt%, especially 0.015–0.05 wt%, and specifically 0.02–0.04 wt%, of the pyrithione salt. This can be achieved by adding the appropriate amount of the biocidal agent.

[0040] The weight ratio of bronopol to pyrithione salt is preferably in the range of 30:70 - 70:30, in particular 40:60 - 60:40, and specifically 50:50.

[0041] The pyrithione salt is in particular sodium pyrithione and / or zinc pyrithione, especially preferably sodium pyrithione.

[0042] According to a preferred embodiment, the construction chemical product is free of isothiazolinone-based biocides. Specifically, the construction chemical product is free of 1,2-benzisothiazolin-3-one (BIT), 2-methyl-4-isothiazolin-3-one (MIT), and / or 5-chloro-2-methyl-4-isothiazolin-3-one (CIT). In particular, the construction chemical product contains none of these three substances.

[0043] Specifically, the construction chemical product additionally contains 0.0005 - 0.01 wt.%, in particular 0.001 - 0.005 wt.%, specifically 0.001 - 0.003 wt.%, of a compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, and / or the reaction product of this compound and 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

[0044] According to another preferred embodiment, the construction chemical product contains at most 0.00015 wt% 1,2-benzisothiazolin-3-one (BIT) and / or 2-methyl-4-isothiazolin-3-one (MIT) and the construction chemical product is free of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

[0045] The pH value of the construction chemical product is preferably in the range of 6-9.

[0046] The construction chemical product may, if necessary, include further components selected, for example, from the group consisting of organic solvents, water, drying agents, thickeners, plasticizers, dispersants, wetting agents, tackifiers, phenolic resins, hydrocarbon resins, natural resins and their derivatives, rubbers, pigments, dyes, pH regulators and / or oxidation inhibitors.

[0047] Another aspect of the present invention relates to a process for the production and / or preservation of a construction chemical product, in particular a construction chemical product as described above, wherein bronopol and a pyrithione salt are added before, during and / or after production, and further comprising the step of adding a compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, wherein the compound is added in an amount which makes it possible to decompose all of the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in one or more of the components of the construction chemical product.

[0048] In the process, preferably 0.005 - 0.1 wt.%, in particular 0.015 - 0.05 wt.%, specifically 0.02 - 0.04 wt.%, of the bronopol and 0.005 - 0.1 wt.%, in particular 0.015 - 0.05 wt.%, specifically 0.02 - 0.04 wt.%, of the pyrithione salt are added.

[0049] In the manufacture and / or preservation of the construction chemical product, the bronopol and the pyrithione salt are mixed with an aqueous polymer dispersion and optionally fillers. The aqueous polymer dispersion and the fillers are those described above in connection with the construction chemical product according to the invention. The aforementioned proportions are preferably used.

[0050] Furthermore, the processes include the step of adding a compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine. The proportions are selected specifically as described above in connection with the biocidal agent and the construction chemical product according to the invention. This ensures that any 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) present in the formulation components used can be decomposed.

[0051] The compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) is added in an amount sufficient to decompose all 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in one or more of the formulation components of the construction chemical product, so that the manufactured or preserved construction chemical product is free of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

[0052] Different approaches to the production of a construction chemical product are described below.

[0053] In a first particularly advantageous process for the production of construction chemical products, only formulation components free of isothiazolinone-based biocides are used, in particular free of 1,2-benzisothiazolin-3-one (BIT), 2-methyl-4-isothiazolin-3-one (MIT), and / or 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), wherein the biocide used according to the invention, comprising bronopol and a pyrithione salt, is added before, during, and after the mixing of the components. This results in preserved construction chemical products free of isothiazolinone-based biocides.

[0054] In a second particularly advantageous process for the production of construction chemical products, formulation components containing 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) are used, wherein a biocidal agent according to the invention comprising bronopol and a pyrithione salt containing a compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) is added before, during and after the mixing of the formulation components. If the compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, is added in an amount that makes it possible to decompose all the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in one or more of the formulation components of the construction chemical product, a construction chemical product will be obtained that is free of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

[0055] This second process thus allows the use of raw materials that are protected with problematic biocides, but are completely decomposed during the process.

[0056] In a third particularly advantageous process for the production of construction chemical products, formulation components are used which, in addition to 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), additionally contain 1,2-benzisothiazolin-3-one (BIT) and / or 2-methyl-4-isothiazolin-3-one (MIT), wherein, before, during and after the mixing of the components, a biocidal agent according to the invention comprising bronopol and a pyrithione salt containing a compound which decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) is added. The compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) is added in an amount that makes it possible to decompose all 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in one or more of the formulation components of the construction chemical product, so that a construction chemical product is obtained that is free of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).Preferably, the total content of 1,2-benzisothiazolin-3-one (BIT) and / or 2-methyl-4-isothiazolin-3-one (MIT) is less than 0.00015 wt.%, based on the total weight of the construction chemical product.

[0057] This third process thus allows the use of raw materials that are protected with several problematic biocides, but are partially decomposed during the process, so that the content of problematic biocides is reduced to an unproblematic level.

[0058] The inventive process comprises in each case the step of adding a compound that decomposes 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular the addition of cysteine, wherein the compound is added in an amount that makes it possible to decompose all of the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in one or more of the components of the construction chemical product.

[0059] The biocidal agent is used in particular to reduce infestation with Pseudomonas aeruginosa, Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Pluralibacter gergoviae, Aspergillus brasiliensis, Penicillium expansum, Trichoderma viride and / or Candida albicans.

[0060] The construction chemical product is a water-based product, or a product that contains a proportion of water before processing.

[0061] This is an adhesive. Specifically, it is a flooring adhesive, a tile adhesive, a construction adhesive, or a wood adhesive. Examples

[0062] The following are exemplary embodiments intended to further illustrate the described invention. Of course, the invention is not limited to these described embodiments.

[0063] Table 1 shows the compositions of three construction chemical adhesive formulations. Examples V1 and V2 are comparative examples not in accordance with the invention. Example B1 is an example in accordance with the invention.

[0064] The adhesive formulations were prepared by mixing the components in a mixer. All formulation components are commercially available products.

[0065] Subsequently, the adhesive formulations were infected three times under identical conditions with a standard solution containing a mixture of various microorganisms, and the microbial count was determined after 6 days. The standard solution contained a mixture of Pseudomonas aeruginosa, Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Pluralibacter gergoviae, Aspergillus brasiliensis, Penicillium expansum, Trichoderma viride, and Candida albicans. Table 1 component V1 V2 B1 Polymer dispersion 1)< 38 38 38 Calcium carbonate 2)< 25 25 12 Calcium carbonate 3)< 12 12 12 Triethylene glycol esters of rosin 18 18 18 BIT 4)< - 0.03 - CIT / MIT 5)< - 0.0008 - Cysteine 0.002 - 0.002 Bronopol - - 0.03 Sodium pyrithione - - 0.03 Water 3.90 3.87 3.84 Process chemicals 6)< 3.1 3.1 3.1 Content of microorganisms 7)< > 10 7< 0 0 1) Vinyl acetate / ethylene copolymer in water (60 wt% solids content; preserved with 14 ppm CIT / MIT) 2) D50 = 35 µm 3) D50 = 10 µm 4) 1,2-Benzisothiazolin-3-one 5) Mixture of 3 parts by weight of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) and 1 part by weight of 2-methyl-4-isothiazolin-3-one (MIT) 6) Thickener, defoamer, pH regulator 7) Microorganisms per gram after 6 days

[0066] The polymer dispersion used for the examples was, as indicated in Table 1, protected by the manufacturer with 14 ppm CIT / MIT. In experiment V1, however, the addition of cysteine ​​completely decomposed the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT). The concentration of the remaining 2-methyl-4-isothiazolin-3-one (MIT) was too low to achieve effective preservation. Consequently, a high number of microorganisms (> 10⁷) was observed.

[0067] In experiment V2, cysteine ​​was omitted. Instead, an additional biocide (a CIT / MIT mixture) was added. This resulted in good preservation, as evidenced by the absence of detectable microorganisms. However, experiment V2 yielded an adhesive formulation containing a relatively high proportion of allergenic isothiazolinone-based biocides.

[0068] In Example B1, the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) contained in the polymer dispersion was completely decomposed due to the addition of cysteine, as in Experiment V1. However, effective preservation was achieved due to the addition of the biocidal agent according to the invention (bronopol and sodium pyrithione in equal parts by weight). As in Experiment V2, no microorganisms could be detected in this case either. Furthermore, the adhesive obtained in this way was free of 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), and the 2-methyl-4-isothiazolin-3-one (MIT) content was below 1.5 ppm, which is unproblematic.

[0069] However, the above examples are to be understood as illustrative examples only.

Claims

1. Construction-chemical product containing a biocidal agent comprising bronopol and a pyrithione salt and additionally containing a compound that breaks down 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, wherein the construction-chemical product is an adhesive, in particular a floor covering adhesive, containing an aqueous polymer dispersion and in addition fillers, having a proportion of polymer dispersion of 35-55% by weight, and a proportion of fillers, in particular sand and / or calcium carbonate, of 25-50% by weight; all proportions being based on the total weight of the adhesive.

2. Construction-chemical product according to Claim 1, wherein the mass fraction of the polymer in the polymer dispersion, based on the weight of the polymer dispersion, is 25-70% by weight, in particular 40-65% by weight.

3. Construction-chemical product according to either of Claims 1 or 2, wherein the proportion of bronopol is 0.005-0.1% by weight, in particular 0.015-0.05% by weight, especially 0.02-0.04% by weight, and the proportion of the pyrithione salt is 0.005-0.1% by weight, in particular 0.015-0.05% by weight, especially 0.02-0.04% by weight.

4. Construction-chemical product according to any of Claims 1-3, containing 0.0005-0.01% by weight, in particular 0.001-0.005% by weight, especially 0.001-0.003% by weight, of the compound that breaks down 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, and / or containing a reaction product of said compound with 5-chloro-2-methyl-4-isothiazolin-3-one (CIT).

5. Construction-chemical product according to any of Claims 1-4, wherein the pH of the product is in the range of 6-9.

6. Method for the production and / or preservation of a construction-chemical product according to any of Claims 1-5, comprising the step of adding bronopol and a pyrithione salt before, during and / or after production of the construction-chemical product and additionally comprising the step of adding a compound that breaks down 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), in particular cysteine, wherein the compound is added in an amount that makes it possible to break down all the 5-chloro-2-methyl-4-isothiazolin-3-one (CIT) present in one or more of the constituents of the construction-chemical product.

7. Method according to Claim 6, wherein 0.005-0.1% by weight, in particular 0.015-0.05% by weight, especially 0.02-0.04% by weight, of the bronopol and 0.005-0.1% by weight, in particular 0.015-0.05% by weight, especially 0.02-0.04% by weight, of the pyrithione salt are added.