Water-based industrial products stabilized against microbial contamination

Abstract

The present invention relates to an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries, and pigment preparations, characterized in that the industrial product contains (a) 0.03% to 1.4% by weight of guanidine and / or at least one salt of guanidine, where said percentage by weight is based on the guanidine content of the entire aqueous industrial product, and has a pH in the range of 7.5 to 12.0. The present invention also relates to a method for stabilizing an aqueous industrial product against microbial contamination, comprising: (a) providing an aqueous industrial product; (b) mixing 0.03% to 1.4% by weight of at least one salt of guanidine with the aqueous industrial product; and (c) optionally adjusting the pH so that the stabilized aqueous industrial product has a pH in the range of 7.5 to 12.0. The present invention also relates to a method for producing an aqueous industrial product.

Description

[Technical Field]

[0001] The present invention relates to an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries, and pigment preparations, characterized in that the industrial product contains (a) 0.03% to 1.4% by weight of guanidine and / or at least one salt of guanidine, said percentage by weight being relative to the guanidine content of the entire aqueous industrial product, and has a pH in the range of 7.5 to 12.0. The present invention also relates to a method for stabilizing an aqueous industrial product against microbial infestation, comprising the following method steps: (a) providing an aqueous industrial product, (b) mixing 0.03% to 1.4% by weight of at least one salt of guanidine with the aqueous industrial product, and (c) optionally adjusting the pH so that the stabilized aqueous industrial product has a pH in the range of 7.5 to 12.0. The present invention also relates to a method for producing an aqueous industrial product. [Background technology]

[0002] Industrial products, especially water-based industrial products such as paints, varnishes, glazes, primers and emulsions, are usually produced using natural or biodegradable raw materials. These raw materials and the water used as a solvent are often contaminated with microorganisms such as bacteria, yeasts and fungi. If these products are produced without preservatives, they may have high microbial counts even one day after production.

[0003] To ensure that hygiene requirements are met by these products and, where appropriate, also by the components used in their production, and thus that the shelf life of the industrial product is guaranteed, so-called biocides are usually added to the product or directly to the components.

[0004] One class of biocides used in the preservation of aqueous coating compositions such as paints, primers, varnishes, or glazes, or their components, is called 3-isothiazolin-3-ones. This class of substances includes highly active compounds as antimicrobials, sometimes with different action profiles. To reduce the amount of biocide used, synergistic combinations of different 3-isothiazolin-3-ones are often used. For example, WO 99 / 08530 proposes the use of methylisothiazolin-3-one and 1,2-benzisothiazolin-3-one in combination.

[0005] A further class of biocides is alkylguanidinium salts, also known as polyguanidinium salts. It is known, for example from "Directory of microbicides for the protection of materials", Springer 2005, pp. 726-731, that medium- and long-chain guanidines, as well as biguanidines, such as cocopropylenediamine-1,5-bisguanidinium acetate, bis(guanidinooctyl)amine triacetate, poly(hexamethylenebiguanidine) hydrochloride, di(4'-chlorophenyldiguanido)hexane, chlorhexidine digluconate, and chlorhexidine diacetate, possess antibacterial activity.

[0006] It is also known to use such medium- and long-chain guanidine compounds in combination with other antibacterial and / or fungicidal active substances. Known examples include 3-iodo-2-propynyl butylcarbamate or a combination with formaldehyde-releasing agents. For example, European Patent Application Publication No. 0891710 teaches the combined use of dodecylguanidine hydrochloride and IPBC. However, the use of dodecylguanidine salts for preserving coating compositions and polymer dispersions has proven problematic; for example, incompatibility in the form of coagulum can be observed when these salts are added.

[0007] In some cases, the use of conventional biocides or preservatives is not even considered, as they are often subject to legal restrictions.

[0008] Thus, suggestions have been made to create shelf-stable aqueous coating compositions of the type contemplated herein by raising their pH to a level that effectively prevents the spread of microorganisms without the inclusion of conventional preservatives, the target pH being at least 10, since lower pH values ​​do not prevent the spread of microorganisms with sufficient certainty.

[0009] For example, in the prior art, eg according to EP 1 297 079, the pH is increased by adding water glass.

[0010] Alternatively, DE 10 2014 013 455 and WO 2017 / 144694 disclose the use of siliconates as pH-increasing additives.

[0011] However, a drawback of the above-described preservation methods is that they require special care in handling due to the relatively high pH required for preservation. Also, there has been an increasing observation in recent years of infestations of these coating compositions with alkaliphilic bacteria, microorganisms that can survive and grow under alkaline conditions.

[0012] Despite the numerous known combinations of active ingredients or measures employed so far, increasing regulatory constraints in particular are causing an increasing demand for products stabilized against microbial infestation, preferably excluding or requiring only a reduced content of conventional preservatives or biocides, such as isothiazolinones, bronopol and pyrithione. Summary of the Invention

[0013] The object is to provide an aqueous industrial product stabilized against the infestation of microorganisms, selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations, (a) 0.03% to 1.4% by weight, preferably 0.07% to 1.2% by weight, more preferably 0.1% to 1.0% by weight of guanidine and / or at least one salt of guanidine, said proportion by weight being relative to the guanidine content of the entire aqueous technical product, This is achieved by an aqueous industrial product, characterized in that the industrial product has a pH in the range of 7.5 to 12.0, preferably 8 to 11.5, and more preferably 8.5 to 11.

[0014] Due to their composition, the aqueous industrial products of the present invention stabilized against microbial infestation require significantly lower levels, and in some cases even none, of the preservatives typically present in such products for in-can storage. Nevertheless, due to the surprisingly effective interaction of guanidine or guanidine salts and the corresponding pH in the range of 7.5 to 12.0, these products are characterized by excellent resistance to microbial infestation, especially during storage. As a result, the above-identified industrial products are significantly improved in terms of environmental compatibility and also possess all known properties in terms of good and safe processing characteristics. Furthermore, the products of the present invention are particularly protected against the infestation of compatible alkaliphilic microorganisms, especially alkaliphilic bacteria and neutrophilic to weakly alkaliphilic bacteria. As a result, the formulations can be less alkaline, which is advantageous in terms of safe processing.

[0015] In a preferred embodiment of the present invention, the aqueous industrial product is essentially free, and preferably completely free, of preservatives selected from the group consisting of 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 1,2-benzisothiazolin-3-one, N-butyl-1,2-benzisothiazolin-3-one, N-methyl-1,2-benzisothiazolin-3-one, octylisothiazolinone, dichlorooctylisothiazolinone, dithiobisbenzmethylamide, formaldehyde and formaldehyde-releasing substances, quaternary ammonium compounds, bronopol, dibromonitrilopropionamide, dibromodicyanobutane, iodopropynyl butylcarbamate, thiabendazole, sodium pyrithione, zinc pyrithione, o-phenylphenol, and combinations thereof.

[0016] By "essentially free" in this context is meant that the entire industrial product contains a total amount of less than 10 ppm, preferably less than 5 ppm, and more preferably less than 1 ppm, based on the entire product.

[0017] For the purposes of this invention, water-based industrial products generally refer to water-containing industrial products selected from the group consisting of paints, e.g., interior paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment formulations, which contain component (a) and have a pH within the ranges set forth in the claims.

[0018] The water-based industrial products according to the invention include the following industrial products: coating compositions, such as paints, pigments, primers, varnishes and glazes; polymer dispersions based on polyacrylate, polystyrene-acrylate, styrene-butadiene or polyvinyl acetate, - pigment preparations, color pastes and tinting pastes, and raw materials, such as slurries or pastes of inorganic or organic color pigments, for example iron oxide pigments and carbon black pigments, or slurries or pastes of inorganic or synthetic fillers and pigments, for example kaolin, calcium carbonate, calcium silicate hydrate, calcium aluminate sulfate, titanium dioxide, gypsum, bentonite, magnesium silicate, smectite or talc; Includes:

[0019] More preferably, the water-based industrial product of the present invention is a paint, primer, varnish, or glaze. The paint may be an interior paint or an exterior paint. The primer may similarly be an exterior primer, or may otherwise be for interior use. The primer may similarly be an exterior sealing or spackling compound, or may otherwise be for interior use.

[0020] In the context of the present invention, the unit "% by weight" in each case relates to the total aqueous technical product.

[0021] By "at least one salt of guanidine" in the context of the present invention is meant that the aqueous technical product contains one, two, three, four, five or six salts of guanidine, i.e. also mixtures thereof.

[0022] The aqueous industrial product of the present invention contains, as component (a), guanidine and / or at least one salt of guanidine in an amount ranging from 0.03% to 1.4% by weight, particularly to achieve stabilization against microbial infestation during storage, where the weight percentage relates to the guanidine content of the entire industrial product. The amount of component (a) required for stabilization in each case can be determined by a person skilled in the art with the aid of familiar methods for the respective product. Aqueous industrial products stabilized against microbial infestation have improved stability against microbial infestation and are therefore less prone to microbial infestation compared to unstabilized aqueous industrial products, i.e., products that do not contain guanidine or guanidine salts or contain too little guanidine or guanidine salts. In the context of the present invention, it has been found that an amount of guanidine of 1.5% by weight or less, preferably 1.2% by weight or less, and more preferably 1% by weight or less, is sufficient to ensure stabilization of the product against microbial infestation. From a practical, especially economic, standpoint, the use of guanidine in amounts higher than, for example, 1.4% by weight is undesirable for stabilization.

[0023] The aqueous industrial product is characterized in that component (a) is present in the aqueous industrial product in an amount ranging from 0.03% to 1.4% by weight, preferably in an amount ranging from 0.07% to 1.2% by weight, more preferably in an amount ranging from 0.1% to 1.0% by weight, wherein said proportion by weight is determined by the formula shown below in the total aqueous industrial product: [ka] The determination of the guanidine content is therefore based solely on the content of guanidine without any counterion in the presence of a guanidine salt.

[0024] The guanidine salts that may be present in the aqueous industrial product are preferably at least one guanidine salt selected from the group consisting of guanidine hydrochloride, guanidine carbonate, guanidine nitrate, guanidine sulfate, guanidine thiocyanate, guanidine phosphate, guanidine hydrogencarbonate, guanidine formate, guanidine acetate, guanidine silicate and / or guanidine citrate, where by at least one guanidine salt it is meant that one, two, three, four, five or even more guanidine salts may be present.

[0025] In the context of the present invention, salts of guanidine are those of the general formula shown below: [ka] (wherein n is 1, 2 or 3; and the counter ion X n- is, for example, chloride, carbonate, nitrate, sulfate, thiocyanate, phosphate, bicarbonate, formate, acetate or citrate) is an unsubstituted guanidine or guanidinium salt of

[0026] In a preferred embodiment of the invention, the aqueous industrial product contains guanidine hydrochloride and / or guanidine carbonate as component (a), and in a particularly preferred embodiment of the invention, the aqueous industrial product contains guanidine carbonate as component (a).

[0027] The pH of aqueous industrial products is generally in the range of pH 7.5 to 12. In a preferred embodiment of the present invention, the aqueous industrial product is characterized by having a pH in the range of 8 to 11.5, preferably in the range of 8.5 to 11. Adjusting the pH to a value in the range of 8.5 to 11 results in industrial products, such as coating compositions, that are more gentle on the skin and therefore have further improved properties. This results in lower requirements, especially regarding the handling of the products of the present invention.

[0028] The pH can be adjusted to within the ranges claimed using means well known to those skilled in the art.

[0029] This can be achieved, for example, by using guanidine carbonate as a guanidine salt. The pH can also be adjusted to the claimed range by adding alkaline substances, also called alkalizing agents. Such compounds for adjusting the pH are known to those skilled in the art; the amount of each used can vary over a wide range and can be ascertained by those skilled in the art with the aid of familiar methods. Examples of alkalizing agents are: guanidine carbonate, alkali metal hydroxides, such as lithium hydroxide, sodium hydroxide and / or potassium hydroxide; alkaline earth metal hydroxides, such as magnesium hydroxide, calcium hydroxide and / or barium hydroxide, ammonium hydroxide, xonotlite and / or ettringite (Ca6[Al(OH)6]2(SO4×26H2O)), Water glasses, such as sodium, lithium and potassium water glasses, or mixtures thereof; Siliconates, such as alkali metal alkyl siliconates or alkaline earth metal alkyl siliconates, in particular those of the general formula R—Si(OH)2OM A or [R-Si(OH)2O]2M E (M in the formula A is an alkali metal, e.g., lithium, sodium, potassium, and M Eis an alkaline earth metal, for example magnesium or calcium, and R is an alkyl group, for example methyl, ethyl, n-propyl, i-propyl, n-butyl or i-butyl, buffer systems, for example based on at least one phosphate or polyphosphate, preferably KPO or NaPO, and at least one alkali metal hydroxide, preferably lithium hydroxide, sodium hydroxide and / or potassium hydroxide; alkali metal and / or alkaline earth carbonates and / or hydrogen carbonates, ammonia and ammonium compounds, Amines, amino compounds and amino alcohols is.

[0030] In a preferred embodiment of the invention, the pH is adjusted to the claimed ranges using guanidine carbonate.

[0031] In the context of the present invention, by aqueous industrial products is meant that the products have a water content that makes them susceptible to the infestation of microorganisms.

[0032] For the purposes of the present invention, a water-based industrial product refers to a product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries, and pigment preparations, particularly water-based paints, varnishes, glazes, or primers, having a water content of at least 10% by weight, preferably at least 15% by weight, and more preferably at least 20% by weight. The paint may be a paint for indoor use or a paint for outdoor use. The primer may similarly be a primer for outdoor use, otherwise for indoor use. Naturally, in the context of the present invention, the primer may also be a spackling compound for outdoor use, otherwise for indoor use. As already outlined in the introduction, such water-based industrial products are typically produced using natural or biodegradable raw materials. These raw materials and the water used as a solvent are often contaminated with microorganisms such as bacteria, yeasts, and fungi. The water content of the water-based industrial product can vary over a wide range, preferably ranging from 10% to 90% by weight, based on the total water-based industrial product.

[0033] As already mentioned in the introduction of this specification, there have been proposals to provide storage-stable aqueous coating compositions of the type in question, such as paints and primers, with a low, preferably zero, content of conventional preservatives by increasing their pH to effectively prevent the spread of microorganisms, with a target pH of at least 10. For example, in the prior art, the pH is increased by adding water glass, for example, according to EP 1 297 079. Alternatively, DE 10 2014 013 455 and WO 2017 / 144694 disclose the use of siliconates as pH-increasing additives.

[0034] However, a drawback of these approaches to solutions is that the high pH values ​​required for coating compositions require special care in their handling. Moreover, in recent years, there has been an increasing observation of infestations by alkaliphilic bacteria in these coating compositions. Therefore, there has been a need for products, such as paints and primers, that are stabilized against microbial infestation, requiring a reduced content of conventional preservatives, preferably excluding conventional preservatives or biocides, such as isothiazolinones, pyrithiones, and formaldehyde.

[0035] This further object is to provide a coating selected from paints and primers, (a) 0.03% to 1.4% by weight, preferably 0.07% to 1.2% by weight, more preferably 0.1% to 1.0% by weight of guanidine and / or at least one salt of guanidine, said proportion by weight being related to the guanidine content of the entire aqueous technical product, (b) 1.0% to 85% by weight of pigments and / or fillers; (c) 1% to 30% by weight, calculated on solids, of a polymer dispersion; and (d) Water in proportions up to 100% by weight Including, This is achieved by an aqueous industrial product stabilized against the spread of microorganisms, characterized in that the industrial product has a pH in the range of pH 7.5 to 12.0, preferably in the range of pH 8.5 to pH 11.5, or is adjusted to a pH in the range of pH 7.5 to 12.0, preferably in the range of pH 8.5 to pH 11.5.

[0036] Surprisingly, in connection with this embodiment of the present invention, it has been found that the presence of guanidine or a salt thereof in an aqueous industrial paint or primer having a pH in the range of 7.5 to 12.0, preferably 8.5 to 11.5, provides a product that is significantly less susceptible to microbial infestation than those known from the prior art. Due to their composition, the paints or primers of the present invention in this embodiment require significantly lower levels of preservatives in the form of so-called biocides that are typically present in coating compositions such as emulsion paints and primers for in-can storage, and in preferred embodiments of the present invention, do not require any such preservatives at all, yet still have excellent storage stability. However, for outdoor use, additional biocides, such as algicides and fungicides, may be added to the paint or primer as needed to protect the film.

[0037] In this preferred embodiment of the invention, the industrial product, which is a paint or primer, is essentially free, preferably completely free, of preservatives selected from the group consisting of 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 1,2-benzisothiazolin-3-one, N-butyl-1,2-benzisothiazolin-3-one, N-methyl-1,2-benzisothiazolin-3-one, octylisothiazolinone, dichlorooctylisothiazolinone, dithiobisbenzmethylamide, formaldehyde and formaldehyde-releasing substances, quaternary ammonium compounds, bronopol, dibromonitrilopropionamide, dibromodicyanobutane, iodopropynyl butylcarbamate, thiabendazole, sodium pyrithione, zinc pyrithione, o-phenylphenol, and combinations thereof.

[0038] By "essentially free" in this context is meant that the water-based industrial product as a whole contains a total amount of less than 10 ppm, preferably less than 5 ppm, and more preferably less than 1 ppm, based on the total water-based industrial product.

[0039] The salts of guanidine that may be present in the water-based industrial product, which may be a paint or primer, are generally at least one guanidine salt selected from the group consisting of guanidine hydrochloride, guanidine carbonate, guanidine nitrate, guanidine sulfate, guanidine thiocyanate, guanidine phosphate, guanidine bicarbonate, guanidine formate, guanidine acetate, and / or guanidine citrate, where by at least one guanidine salt it is meant that one, two, three, four, five, or even more guanidine salts may be present.

[0040] In a preferred embodiment of the invention, the water-based industrial product, which is a paint or primer, contains guanidine hydrochloride and / or guanidine carbonate as component (a), and in a particularly preferred embodiment of the invention, the water-based industrial product contains guanidine carbonate as component (a).

[0041] The pH of the aqueous industrial product in this embodiment is generally in the range of pH 7.5 to 12. In a preferred embodiment of the invention, the aqueous industrial product is characterized by having a pH in the range of pH 8.5 to 11.5. Adjusting the pH to a value in the range of pH 8.5 to 11.5 provides a paint or primer that is more skin-friendly and therefore a product with further improved properties, which is particularly advantageous with regard to its safe processing.

[0042] Water-based industrial products, such as paints or primers, generally contain 1.0% to 85% by weight of pigments and / or fillers as component (b). In a preferred embodiment of the present invention, the coating composition contains 1% to 25% by weight of pigments and / or 5% to 50% by weight of fillers.

[0043] The pigments used can be the usual pigment admixtures for emulsion paints, such as titanium dioxide, iron oxide, chromium oxide, cobalt blue, phthalocyanine pigments, spinel pigments, and nickel and chromium titanates.

[0044] The fillers present in the composition are preferably silicates, carbonates, fluorspar, sulfates and oxides.

[0045] As component (c), aqueous industrial products, such as paints or primers, generally contain 1% to 30% by weight of polymer dispersion, in each case calculated as the solids content of the polymer dispersion, preferably 2% to 20% by weight, more preferably 3% to 12% by weight. Any polymer dispersion known per se from the prior art in the field of coating or paint systems can be used in the polymer dispersion present in the coating composition. The properties of the dispersion, and therefore also of the finished product produced therefrom, are primarily determined by the respective polymer. The polymer is made up of various building blocks called monomers, which can also be combined with one another depending on the desired property profile. Suitable monomers are, for example, vinyl carboxylates having 3 to 20 carbon atoms, N-vinylpyrrolidone, vinyl aromatics, vinyl halides, ethylenically unsaturated carboxylic acids, their esters, amides, or anhydrides, nanohybrid dispersions, water glass, silicone resin emulsions, aqueous polyurethane dispersions, styrene-acrylates, α-olefins and / or 1,3-dienes in the form of aqueous polymer dispersions or water-redispersible polymer powders. Particular preference is given to the use of ethylenically unsaturated carboxylic acids, especially acrylic and methacrylic acid, and also to the use of ethylenically unsaturated carboxylic acid esters, especially acrylic and methacrylic acid esters having 1 to 12 carbon atoms in the alcohol group. The alcohol group of the esters may consist of a linear or branched alkyl chain, cycloaliphatic or aromatic, and may further be modified with hydroxyl groups, halogen atoms or epoxy groups. Particular preference is given to the use of styrene and styrene derivatives.

[0046] As component (d), water-based industrial products, such as paints or primers, contain up to 100% water, which can vary over a wide range and is generally at least 10% by weight, preferably at least 15% by weight, more preferably at least 20% by weight.

[0047] The water-based industrial product, be it a paint or a primer, may also contain additional additives such as dispersants, thickeners, stabilizers, defoamers and / or hydrophobizing agents.

[0048] The present invention also relates to the use of the water-based industrial products of the invention, which are paints or primers, for indoor and outdoor use, which have been found to be particularly suitable for indoor use due to the absence of conventional in-can preservatives.

[0049] The present invention further relates to a method for producing the aqueous industrial product of the present invention, which comprises mixing the ingredients defined above.

[0050] The present invention further provides a method for stabilizing an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations against microbial infestation, comprising the following method steps: (a) providing a water-based industrial product; (b) mixing at least one salt of guanidine with the industrial product; and (c) optionally adjusting the pH wherein the stabilized aqueous technical product has a pH in the range of 7.5 to 12.0, preferably 8 to 11.5, more preferably 8.5 to 11, and further characterized in that the amount of guanidine salt(s) is in the range of 0.03% to 1.4% by weight, preferably in the range of 0.07% to 1.2% by weight, more preferably in the range of 0.1% to 1.0% by weight, wherein said percentage by weight relates to the guanidine content of the entire aqueous technical product.

[0051] Advantageously, the method of the present invention is characterized in that it can be used to produce aqueous industrial products that are stabilized against microbial infestation and, due to their composition, require significantly lower levels of preservatives, or in some cases no preservatives at all, that are typically present in aqueous industrial products, such as emulsion paints for in-can storage. Nevertheless, due to the surprisingly effective interaction of at least one guanidine salt or guanidine obtained therefrom and the corresponding pH in the range of 7.5 to 12.0, these aqueous industrial products are characterized by excellent resistance to microbial infestation, especially during storage. As a result, the products are significantly improved in terms of their environmental compatibility.

[0052] In step (a) of the method of the present invention, an aqueous industrial product to be stabilized against microbial infestation is provided, the product being selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations. By stabilized against microbial infestation in the context of the present invention, it is meant that in the unstabilized state, the product is prone to microbial infestation and therefore spoilage, especially during storage.

[0053] The aqueous industrial product prepared in step (a) is mixed with at least one salt of guanidine in step (b). The amount of guanidine salt required for stabilization can be determined by a person skilled in the art according to the respective product using familiar methods. Aqueous industrial products stabilized against microbial infestation have improved stability against microbial infestation compared to unstabilized aqueous industrial products, i.e., products that do not contain guanidine salt or guanidine or contain too little guanidine salt or guanidine, and therefore are less likely to be infested with microorganisms.

[0054] The amount of guanidine salt(s) used in process step (b) may vary over a range depending on the product provided, and is in the range of 0.03% to 1.4% by weight, preferably in the range of 0.07% to 1.2% by weight, more preferably in the range of 0.1% to 1.0% by weight, whereby said percentages by weight are based on the guanidine content in the entire aqueous product, not including any counterions.

[0055] In a preferred embodiment of the invention, guanidine hydrochloride and / or guanidine carbonate, in a particularly preferred embodiment of the invention, guanidine carbonate is used in process step (b).

[0056] In process step (c) of the process for stabilizing an aqueous technical product, the pH is optionally adjusted so that the aqueous technical product has a pH in the range of pH 7.5 to 12.0, preferably in the range of pH 8 to 11.5, more preferably in the range of pH 8.5 to 11. By "optionally" here, it is meant that no adjustment is necessary if, after process step (b), as a result of the composition of the product or otherwise as a result of the guanidine salt used, the pH is already in the range of pH 7.5 to 12.0, preferably in the range of pH 8 to 11.5, more preferably in the range of pH 8.5 to 11.

[0057] The present invention further provides a method for producing an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations stabilized against microbial infestation, comprising the following method steps: (a) providing a water-based industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries, and pigment formulations; (b) mixing at least one salt of guanidine with the aqueous industrial product such that the amount of guanidine salt is in the range of 0.03% by weight to 1.4% by weight based on the guanidine content of the entire aqueous industrial product; and (c) optionally adjusting the pH wherein the aqueous industrial product produced has a pH in the range of 7.5 to 12.0, preferably in the range of 8 to 11.5, and more preferably in the range of 8.5 to 11.

[0058] Advantageously, the process of the present invention is characterized in that it can be used to produce aqueous industrial products that are stabilized against microbial infestation and, due to their composition, require significantly lower levels of preservatives, or even no preservatives at all, that are typically present in these products for in-can storage. Nevertheless, due to the surprisingly effective interaction of the at least one guanidine salt and the corresponding pH in the range of 7.5 to 12.0, the industrial products are characterized by excellent resistance to microbial infestation, especially during storage.

[0059] In step (a) of the process of the present invention, an aqueous industrial product to be stabilized against microbial infestation is provided, the product being selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations. By stabilized against microbial infestation in the context of the present invention, it is meant that in the unstabilized state, the product is prone to microbial infestation and therefore spoilage, especially during storage.

[0060] The aqueous industrial product prepared in step (a) is mixed with at least one salt of guanidine in step (b). The amount of guanidine salt required for stabilization can be determined by those skilled in the art according to the respective product using familiar methods. Products stabilized against microbial infestation have improved stability against microbial infestation compared to unstabilized compositions, i.e., compositions that do not contain unsubstituted guanidine salts or contain too little guanidine salt, and are therefore less likely to be infested by microorganisms.

[0061] The amount of guanidine salt(s) used in process step (b) can vary over a wide range depending on the product provided and is in the range of 0.03% to 1.4% by weight, preferably in the range of 0.07% to 1.2% by weight, more preferably in the range of 0.1% to 1.0% by weight, said percentages by weight being based on the guanidine content of the entire aqueous technical product, not including any counterions.

[0062] In a preferred embodiment of the invention, guanidine hydrochloride and / or guanidine carbonate is used in process step (b), and in a particularly preferred embodiment of the invention, guanidine carbonate is used.

[0063] In process step (c) of the process for producing an aqueous industrial product, the pH is optionally adjusted so that the product produced has a pH in the range of pH 7.5 to 12.0, preferably in the range of pH 8 to 11.5, more preferably in the range of pH 8.5 to 11. By "optionally" here, it is meant that no adjustment is necessary if, as a result of the product composition or otherwise as a result of the guanidine salt used, the pH is already in the range of pH 7.5 to 12.0, preferably in the range of pH 8 to 11.5, more preferably in the range of pH 8.5 to 11, after process step (b).

[0064] The present invention further relates to the use of guanidine and / or at least one salt of guanidine in an amount ranging from 0.033% to 2.0% by weight, preferably from 0.07% to 1.7% by weight, more preferably from 0.1% to 1.4% by weight, for stabilizing an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries, and pigment preparations having a pH ranging from 7.5 to 12.0, preferably from 8 to 11.5, and more preferably from 8.5 to 11, said weight percentage being relative to the guanidine content, not including any counterions, of the entire aqueous industrial product against microbial infestation. Advantageously, the use of guanidine or at least one guanidine salt as defined above in aqueous industrial products according to the present invention makes it possible to dispense with conventional preservatives typically present in such products for in-can storage. As a result, the product is significantly improved in terms of its environmental compatibility. The claimed aqueous industrial product also has all the known properties for good and safe processing characteristics. Furthermore, the product of the invention is particularly protected against infestation by adapted alkaliphilic microorganisms and against neutrophilic to weakly alkaliphilic microorganisms.

[0065] In a preferred embodiment, the present invention relates to a coating composition selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment formulations, (a) 0.03% to 1.4% by weight, preferably 0.07% to 1.2% by weight, more preferably 0.1% to 1.0% by weight of guanidine and / or at least one salt of guanidine, said proportion by weight being related to the guanidine content of the entire aqueous technical product, (b) 0.001% to 0.01% by weight, preferably 0.001% to 0.005% by weight, of 5-chloro-2-methylisothiazolin-3-one (CMIT), and (c) Water in proportions up to 100% by weight The present invention relates to an aqueous industrial product comprising the above-mentioned compound, characterized in that the aqueous industrial product has a pH in the range of 9.0 to 11.0 or is adjusted to a pH in the range of 9.0 to 11.

[0066] The advantages of this embodiment of the present invention are primarily that 5-chloro-2-methylisothiazolin-3-one is present in the industrial product as a so-called instant-kill biocide, thereby rapidly and effectively killing bacteria present in the coating composition. This effectively and quickly inactivates microorganisms, such as bacteria, yeast, and fungi, present from the manufacturing process. Furthermore, because the alkaline pH of the aqueous industrial product causes gradual decomposition of 5-chloro-2-methyl-4-isothiazolone, 5-chloro-2-methyl-4-isothiazolone is present only in relatively low concentrations, if any, even after several days, and therefore is not expected to pose a significant problem for end users. Because the aqueous industrial product, having a pH in the range of pH 9 to pH 11, further contains at least one guanidine salt, the product is further effectively stabilized against potential subsequent microbial postcontamination during transportation and storage.

[0067] In a preferred embodiment of the present invention, the aqueous industrial product is characterized in that 5-chloro-2-methyl-4-isothiazolone (CMIT) has a 2-methyl-4-isothiazolin-3-one content in the range of 0% to 2% by weight, based on the total proportion of 5-chloro-2-methyl-4-isothiazolin-3-one.

[0068] This embodiment of the invention makes it possible in an advantageous manner to obtain products stabilized against microbial infestation with highly effective 5-chloro-2-methyl-4-isothiazolin-3-one, which are particularly suitable for individuals who are highly sensitized to 5-chloro-2-methylisothiazolin-3-one or 2-methylisothiazolin-3-one after production and storage. [Example]

[0069] The following examples serve to further illustrate the present invention:

[0070] To demonstrate the stabilization of the claimed aqueous industrial products by the surprising interaction of the alkaline pH range and guanidinium ions with respect to microbial infestation, various emulsion paints with different pH values ​​and calcium carbonate slurries as components were mixed with various amounts of guanidine salts and their stability against microbial infestation was tested:

[0071] The paints and their components tested were as follows: Paint 1: A laboratory-prepared emulsion paint for interior use (pigment volume concentration 77%) with a pH of 7.8 based on a vinyl acetate-ethylene binder and without the addition of any other commonly used preservatives. Paint 2: A laboratory-prepared emulsion paint for interior use (pigment volume concentration 77%) with a pH of 8.4 based on a styrene-acrylate binder and without the addition of any other commonly used preservatives. Paint 3: A commercially available so-called preservative-free alkaline emulsion paint for interior use with a pH of 11.3 (Alpinaweiss Das Original, solvent- and preservative-free).

[0072] Calcium Carbonate Slurry: A preservative-free calcium carbonate slurry with 78% solids and pH 9.2.

[0073] procedure: Paints 1-3 were mixed and homogenized with various concentrations of the guanidinium salt to be tested.

[0074] The resulting batches of paint prepared in this way were repeatedly inoculated with a mixture of different wild-type bacterial strains of practical relevance for contamination: these bacteria had previously been isolated from a commercial emulsion paint containing conventional preservatives that was indeed contaminated with microorganisms (bacterial mixture 1, Pseudomonas genus), and from a commercial alkaline emulsion paint that was so-called preservative-free and was indeed contaminated with microorganisms (bacterial mixture 2, alkaliphilic bacteria of the genera Nesterenkonia and Alkalibacterium).

[0075] The calcium carbonate slurry was stored at 60°C for 3 days for heat sterilization prior to the addition of guanidinium salts. The treated slurry was then mixed and homogenized with various concentrations of guanidinium salts. The prepared slurry was repeatedly inoculated with relevant bacterial strains (bacterial mixture 3).

[0076] Bacteria mixture 1: Pseudomonas spp. (Pseudomonas oleovorans group)DSM 33933 Pseudomonas aeruginosa DSM 33935 Pseudomonas oleovorans DSM 33936 Pseudomonas putida DSM 33937 Pseudomonas aeruginosa DSM 33938

[0077] Bacteria mixture 2: Nesterenkonia sp. DSM 108520 Nesterenkonia sp. DSM 108521 Alkalibacterium pelagium DSM 108522 Nesterenkonia massiliensis DSM 110679 Nesterenkonia sp. DSM 108519

[0078] Bacterial mixture 3: Alcaligenes faecalis NCIMB 13145 Aeromonas hydrophila DSM 6173 Escherichia coli DSM 13631 Burkholderia cepacia DSM 9241 Staphylococcus aureus DSM 799 Pseudomonas aeruginosa DSM 50071 Pseudomonas putida DSM 13624

[0079] The inoculum was added to each sample as a fresh cell suspension in saline (0.9% NaCl) at 2% (v / w) for each inoculum. The cell number of the added inoculum was 10 5 / ml, and 10 in Examples 2 to 5 9 / ml, and 10 in Example 6 6 The total cell counts were 1 / ml, with equal portions of each individual bacterial strain. Cell suspensions were prepared by growing individual bacteria in liquid culture on a shaker at 30°C for 24 hours. The medium used to grow bacteria from bacterial mixture 1 was Mueller-Hinton liquid medium. Bacteria from bacterial mixture 2 were grown in Mueller-Hinton liquid medium previously adjusted to pH 9.5-9.7 with an alkaline buffer solution. After growth, each liquid culture was centrifuged, and the cells were resuspended in saline. To adjust the mixture to the desired cell number, the individual bacterial suspensions were diluted accordingly, if necessary, before combining with saline. The cell number of each inoculum was determined by chamber counting.

[0080] In Example 1, the sample contained 10 cells. 5A single inoculation of a 2% v / w bacterial suspension (Bacteria Mixture 1) was performed, and growth was monitored over 28 days by determining the number of viable bacteria per gram of paint (colony-forming units, CFU / g). CFU / g was determined each time by taking an aliquot (1 g) from the previously homogenized sample, serially diluting it 10-fold in saline (0.9% NaCl), streaking it on tryptone soy agar, and subsequently incubating the agar plates at 30°C for 48 hours.

[0081] In Examples 2 to 6, the so-called repeated stress test using bacteria was carried out using 10 cells. 9 This was done by repeatedly inoculating the samples at specific time intervals with a bacterial suspension containing 1 / ml (2% v / w) of 1% sucrose and monitoring the bacterial evolution by a semi-quantitative evaluation method. After each inoculation, the samples were incubated at 30°C for 6 days (bacterial mixtures 1 and 3) or 7 and 14 days (bacterial mixture 2). After these periods, the bacterial spread was evaluated semi-quantitatively in each case. For this purpose, aliquots were taken from each sample after homogenization using a sterile plastic inoculation loop (10 μl) and uniformly streaked onto agar plates (bacterial mixtures 1 and 3 on tryptone soy agar, and bacterial mixture 2 on DSMZ 31 alkaline nutrient agar). The streaked agar plates were then incubated at 30°C for 48 hours (bacterial mixtures 1 and 3) or 5 to 7 days (bacterial mixture 2). After incubation, the bacterial colonies grown on the agar plates were visually evaluated and quantified according to the following scheme:

[0082] TIFF2026505250000003.tif80149 A total of three inoculation cycles were performed in each repeated stress test.

[0083] The results are shown in Tables 1-6:

[0084] Example 1 / Table 1: [Table 1]

[0085] As can be inferred from the experimental results shown in Table 1, the addition of even 0.05% by weight of guanidine carbonate to paints having a pH of 8.5 or higher causes a clear stabilization of the paint(s) against microbial infestation.

[0086] Example 2 / Table 2: [Table 2]

[0087] As can be seen from the experimental results shown in Table 2, the addition of 0.25% by weight of guanidine hydrochloride to paint 1 having a pH of 8.5 or even 0.25% by weight of guanidine hydrochloride to paint 2 having a pH of 9.0 causes a clear stabilization of the paint(s) against microbial infestation.

[0088] Example 3 / Table 3: [Table 3] TIFF2026505250000007.tif157149

[0089] The experimental results shown in Table 3 clearly show that in the case of paint 1, the addition of 0.8% by weight of guanidine hydrochloride at a pH of 7.5 and the addition of 0.15% by weight of guanidine carbonate at a pH of 9.4 caused a clear stabilization of the paint(s) against microbial infestation. In the case of paint 2, the addition of 0.8% by weight of guanidine hydrochloride at a pH of 7.6 and the addition of 0.175% by weight of guanidine carbonate at a pH of 9.1 caused a clear stabilization of the paint against microbial infestation.

[0090] Example 4 / Table 4: [Table 4]

[0091] The experimental results shown in Table 4 demonstrate that the addition of even 0.1 wt. % guanidine carbonate to paint 1, which has a pH of 9.1 or higher, or to paint 2, which has a pH of 8.9 or higher, causes a clear stabilization of the paint(s) against microbial infestation.

[0092] Example 5 / Table 5: [Table 5]

[0093] The experimental results shown in Table 5 show that for a paint with a pH of 11.2, the addition of 0.1% by weight of guanidine carbonate already causes a clear stabilization of the paint against microbial infestation.

[0094] Example 6 / Table 6 [Table 6]

[0095] The experimental results shown in Table 6 show that for a slurry with a pH of 9.4, the addition of 0.075% by weight of guanidine carbonate already causes a clear stabilization of the slurry against microbial infestation.

Claims

1. A water-based industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment formulations, (a) 0.03% to 1.4% by weight of guanidine and / or at least one salt of guanidine, said percentage by weight being relative to the guanidine content of the entire aqueous technical product; Including, An industrial product characterized by having a pH in the range of 7.5 to 12.

0.

2. 2. The industrial product according to claim 1, characterized in that component (a) is present in the industrial product in the range of 0.07% by weight to 1.2% by weight, said percentage by weight being related to the guanidine content of the entire aqueous industrial product.

3. 3. An industrial product according to claim 1 or 2, characterized in that the at least one guanidine salt is guanidine hydrochloride and / or guanidine carbonate.

4. 4. An industrial product according to any one of claims 1 to 3, characterized in that component (a) is present in the range of 0.1% by weight to 1.0% by weight, said percentage by weight being related to the guanidine content of the entire aqueous industrial product.

5. none.

6. An industrial product according to any one of claims 1 to 4, characterized in that it has a water content ranging from 10% to 90% by weight.

7. The industrial product according to any one of claims 1 to 4, selected from paints and primers, (a) 0.03% to 1.4% by weight of guanidine and / or at least one salt of guanidine, said percentage by weight being related to the guanidine content of the entire aqueous technical product; (b) 1.0% to 85% by weight of pigments and / or fillers; (c) 1% to 30% by weight, calculated on solids, of a polymer dispersion; and (d) Water in proportions up to 100% by weight Contains An industrial product characterized by having a pH in the range of 7.5 to 12.0 or adjusted to a pH in the range of 7.5 to 12.

0.

8. The industrial product according to any one of claims 1 to 7, (a) 0.03% to 1.4% by weight of guanidine and / or at least one salt of guanidine, said percentage by weight being related to the guanidine content of the entire aqueous technical product; (b) 0.001% to 0.01% by weight of 5-chloro-2-methylisothiazolin-3-one (CMIT), and (c) Water in proportions up to 100% by weight Contains An industrial product characterized by having a pH in the range of 9.0 to 11.0 or being adjusted to a pH in the range of 9.0 to 11.

9. 9. The industrial product of claim 8, wherein the 5-chloro-2-methyl-4-isothiazolone (CMIT) has a 2-methyl-4-isothiazolin-3-one content ranging from 0% to 2% by weight, based on the total amount of 5-chloro-2-methyl-4-isothiazolin-3-one.

10. 10. The industrial product according to any one of claims 1 to 9, characterized in that it contains one or more preservatives selected from the group consisting of 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 1,2-benzisothiazolin-3-one, N-butyl-1,2-benzisothiazolin-3-one, N-methyl-1,2-benzisothiazolin-3-one, octylisothiazolinone, dichlorooctylisothiazolinone, dithiobisbenzmethylamide, formaldehyde and formaldehyde-releasing substances, quaternary ammonium compounds, bronopol, dibromonitrilopropionamide, dibromodicyanobutane, iodopropynyl butylcarbamate, thiabendazole, sodium pyrithione, zinc pyrithione, and o-phenylphenol in a total amount of less than 10 ppm based on the product.

11. 1. A method for stabilizing an aqueous industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations against microbial infestation, comprising the following method steps: (a) providing a water-based industrial product; (b) mixing at least one salt of guanidine with an aqueous technical product; and (c) optionally adjusting the pH Including, 1. A method wherein the stabilized aqueous industrial product has a pH in the range of pH 7.5 to 12.0, and further characterized in that the amount of guanidine salt(s) is in the range of 0.03% to 1.4% by weight, said percentage by weight being relative to the guanidine content of the entire aqueous industrial product.

12. 12. The method according to claim 11, characterized in that the at least one guanidine salt is guanidine hydrochloride and / or guanidine carbonate.

13. 1. A method for producing a water-based industrial product selected from the group consisting of paints, primers, varnishes, glazes, polymer emulsions, slurries and pigment preparations, comprising the following method steps: (a) providing a water-based industrial product; (b) mixing at least one salt of guanidine with the aqueous industrial product such that the amount of guanidine salt is in the range of 0.03% to 1.4% by weight based on the guanidine content of the entire aqueous industrial product; and (c) optionally adjusting the pH Including, A method characterized in that the aqueous industrial product produced has a pH in the range of pH 7.5 to 12.0.

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