DK1283822T3

DK1283822T3 - Fenolat-containing formulation low freezing point

Info

Publication number: DK1283822T3
Application number: DK01943291.3T
Authority: DK
Inventors: Patrick Schwarzentruber; Matthias Buri
Original assignee: Omya Int Ag
Priority date: 2000-05-12
Filing date: 2001-04-26
Publication date: 2014-03-17
Also published as: DE10027588A1; PT1283822E; ES2458492T3; DE10027588B4; TWI297005B

Description

The present invention relates to an aqueous liquid phenolate-containing formulation with a solidification point of less than or equal to minus 10°C, a method for the preparation thereof, an aqueous suspension or dispersion containing said formulation as well as different industrial applications of said formulation.

Formulations of phenolate derivatives have deficiencies, in particular with respect to their use as preservatives in the technical field, such as in highly concentrated pigment slurries. Salts of phenol, of alkyl- and aryl-substituted phenols, of halogenated phenols as well as of cresols and halogenated cresols are known as fungicidal and bactericidal agents in the protective and curative fields. The majority of formulations of said phenolates are water-soluble alkali salt formulations which are too alkaline for the later intended use; hence, they either have a negative effect on the product to be protected, have a freezing point of 0°C or just below 0°C, tend to crystallize at low temperatures and in high concentrations especially upon seeding with seed crystals, or contain large amounts of organic solvents or large amounts of excess alkali.

In particular, sodium o-phenylphenolate and potassium o-phenylphenolate are known as fungicidal agents for wood and also as preservatives for pigment slurries. Sodium o-phenylphenolate and potassium o-phenylphenolate are available in powder form. Furthermore, sodium o-phenylphenolate is commercially available in the form of a 25% by wt. sodium hydroxide solution and in the form of a 35-38% by wt. emulsion wherein large amounts of emulsifying agents are used for the stabilization thereof. Potassium o-phenylphenolate is commercially available in the form of a 35-39% by wt. potassium hydroxide solution containing 38% by wt. of potassium o-phenylphenolate and 6-10% by wt. caustic potash in water.

Recently, DE 198 59 136.5 has described partially neutralized forms of o-phenylphenol/alkali o-phenylphenolate in water and large amounts of organic solvents such as glycols and aromatic alcohols. DE 42 022 051 A1 also describes highly concentrated liquid forms of various phenol derivatives. Flowever, these are not present in the neutralized form, have melting points of more than +15°C and are water insoluble.

It is difficult to handle sodium o-phenylphenolate in powder form in large amounts. Liquid formulations are clearly preferred.

The transport and storage costs of 25% by wt. aqueous sodium o-phenylphenolate are high. It is impossible to achieve higher concentrations since its solubility is too low. Also in concentrations of only 25% the product tends to crystallize at room temperature. Spontaneous crystallization occurs at temperatures below 0°C. Potassium o- phenylphenolate in concentrations of 35-39% by wt. which contains a high excess of potassium hydroxide is extremely caustic and has a pH of much more than 12. To prevent crystallization at minus 10°C, potassium hydroxide should be present in up to 30% excess. Upon addition to an aqueous pigment slurry with a high solid content, particularly at solid concentrations of > 50 vol. %, this high pH as well as the high ion concentration result in the formation of agglomerates in the pigment slurry as well as in an altered pH of the final product.

If insufficiently sheared during admixing, the partially neutralized phenolates described in DE 198 59 136.5, dissolved in water and glycols, tend to form agglomerates, show separation of the aqueous pigment slurry and the partially neutralized phenolate solution and flotation thereof on the surface of the slurry. Therefore, no optimal preservation is obtained in this case, and the result may be deposits of phenolates in the ducts. In addition, the high proportion of organic solvents in the range of 20-90% by wt. is not desirable for some applications.

The use of emulsified sodium o-phenylphenolate in pigment slurries with a high solid content bears a risk because the emulsifying agent destabilizes the pigment dispersion and tends to form foams. Furthermore, most of the aqueous salt solutions and aqueous emulsions of o-phenylphenol have freezing points at or just below 0°C. Only potassium o-phenylphenolate containing KOH in a high excess has a freezing point of minus 15°C. However, this compound bears the risk of altering the pigment slurry properties such as agglomerate formation and raising of the pH. During the winter in Northern Europe, e.g. in Norway, and in North America and Canada, it is impossible to transport aqueous liquids with solidification points around the freezing point without risking the freezing thereof if no heating is installed in the transport container. The same problem applies to storage. Moreover, it is economically as well as ecologically unreasonable and unaccepted by the industry to transport solutions in such low concentrations over long distances. GB 804 257 describes phenolates and crystallization inhibitors. However, the maximum solubility of sodium pentachlorophenate (NaPCP) in 10% aqueous ethanol is only 27.3% by wt.

It is an object of the present invention to provide a liquid formulation of phenolates with a freezing/ solidification point of less than or equal to -10°C, wherein the solvent system thereof contains a major proportion of water.

According to the present invention, this object has been solved by the liquid aqueous phenolates-containing formulation characterized in more detail in claim 1 which has a solidification point of less than or equal to -10°C. The formulation described herein is comprised of the following components: a) 50-80% by wt. of one or more phenolates; b) 0.1-10% by wt. of at least one crystallization inhibitor selected from one or more aliphatic glycol compound(s), such as ethylene glycol, monopropylene glycol and/or diethylene glycol, and/or benzyl alcohol, 2-phenylethane-l-ol, 3-phenylpropane-l-ol and/or l-phenylpropane-2-ol.; and where the balance with respect to 100% by wt. is comprised of alkali in an excess of 0.03-0.15 mol/mol and water.

The preferred embodiments of the present invention are evident from the dependent claims and the alternative independent claims as well as from the following specification.

The formulation according to the present invention is characterized by containing phenolates in a concentrated form of 50-80% by wt. based on the total formulation. Phenolates means salts of phenols which dissolve in water accompanied by an alkaline reaction. Phenols is an umbrella term for aromatic hydroxy compounds wherein the hydroxy groups are directly bound to the benzene nucleus. Examples of phenols are phenol itself and phenols containing one or more aliphatic and/or aromatic substituents. Examples for these are o-phenylphenol, cresols and resorcinols. In the present formulation, the phenols and their derivatives are present in their completely neutralized form as salts, i.e. in the form of phenolates.

Furthermore, the formulation according to the present invention preferably has a phenolate content, calculated as the corresponding phenol or phenol derivative of more than 40% by wt. The phenolate solution, preferably o-phenylphenolate, is neutralized to 103-115 mol %, based on the phenolate, preferably by means of alkali hydroxides. This means that 1.03-1.15 mols of alkaline substance, preferably alkali hydroxide, per mol of phenolate are added to the phenolate solution. It is particularly preferred to use 105 mol % of KOH, based on the phenolate content, for neutralization.

The phenolates employed according to the present invention exhibit microbicidal effects and therefore act as preservatives. Due to these properties, the formulations according to the present invention may be employed both for preventative and curative protection.

Preferred phenolates are phenolates with one ore more aliphatic and/or aromatic substituents. Examples of such derivatives which may be used according to the present invention are o-phenylphenolate, halogenated phenolates, cresol salts, salts of halogenated cresols and salts of resorcinols or mixtures thereof. Examples of cresol salts are salts of halogenated cresols, in particular salts of chlorinated cresols, salts of o-, m-, and p-cresol, salts of isopropyl o-cresol, salts of 4-isopropyl m-cresol. An example ofa useful resorcinol salt is a salt of 4-n-hexyl resorcinol.

The phenolates are present in amounts of 50-80% by wt. wherein it should be understood that all ranges between 50 and 80% by wt. are also covered by the present invention.

Preferred ranges are 50-75% by wt., 55-75% by wt., 55-70% by wt., 60-70% by wt., 60-65% by wt., 62-67% by wt. and, above all, 65% by wt., each based on the total formulation.

In a preferred embodiment of the present invention, the phenolate solution has been neutralized by alkali hydroxides so that the phenolates are preferably present as the potassium salt, potassium and sodium salt and/or potassium and lithium salt. Particular preferred, the phenolates are present as the potassium salt.

The solvent system for the phenolates preferably contains an excess of 0.03-0.15 mols of alkali hydroxides. Preferably, 1.03-1.15, further preferred 1.05-1.10 mols, of alkali hydroxides per mol of phenolate are used for neutralization. The degree of neutralization with alkali hydroxide, preferably potassium hydroxide, is 102-115 mol %, preferably 103-107 mol % and particularly preferred 105 mol %, based on the phenolate.

Important for the success of the present invention has been the surprising and unforeseeable activity of low amounts of alcohols as crystallization inhibitors.

As crystallization inhibitors, organic water-soluble substances are used, preferably alcohols, in amounts of 0.1-10% or mixtures thereof, e.g. in amounts of 1 to 5% by wt.

As crystallization inhibitors, one or more aliphatic glycol compound(s) are preferably used, such as ethylene glycol, monopropylene glycol and/or diethylene glycol, and/or one or more aliphatic alcohol(s) such as methanol, ethanol, η-, iso-propanol, isomers of butanol, such as 1-butanol, and/or of pentanol, and/or one or more aromatic alcohol(s) such as benzyl alcohol, 2-phenylethane-l-ol, 3-phenylpropane-l-ol and/or l-phenylpropane-2-ol.

Crystallization inhibitors are present in an amount of 0.1-10% by wt, based on the total formulation. Preferred amounts are 0.5-5.0% by wt, further preferred 1-3% by wt., based on the total formulation, wherein it should be understood that all ranges between 1 and 10% by weight may also be used.

Examples of aromatic alcohols which may be preferably used are: benzyl alcohol and/or 2-phenylethane-l-ol and/or 3-phenylpropane-l-ol and/or 1- phenylpropane.

Examples of monovalent aliphatic alcohols which may be preferably used are: methanol, ethanol, propanols, butanols, pentanols.

Examples of aliphatic glycols which may be preferably used are: ethylene glycol, propylene glycol, butanediols, pentanediols.

The phenolate content of the formulation according to the present invention preferably is more than 40% by wt., calculated as the corresponding phenol or phenol derivative. Phenolate solutions wherein o-phenylphenolate is especially preferred, are neutralized to 103-115 mol %, based on the phenolate, preferably with alkali hydroxides, in particular with KOH. In a preferred embodiment, 105 mol % of KOH, based on the phenolate content, are employed for neutralization.

Besides phenolates and crystallization inhibitors, which comprise a proportion of 50.1-90% by wt., the formulation according to the present invention also contains 10-49.9% by wt. of water as well as optionally other constituents such as other microbicidal agents and/or substances promoting microbicidal agents.

The formulation according to the present invention is an aqueous formulation wherein the solvent system comprising a proportion of 20-50% by wt. of the formulation contains 90-99% by wt. of water. Crystallization inhibitors are components of the solvent system and are present in an amount of 0.1-10% by wt., based on the solvent system. However, within these limits it is also possible to replace a proportion of water and/or crystallization inhibitor by other components, for example by other microbicidal agents and substances promoting microbicidal agents. The following microbicidal agents are particularly preferred: amines, primary and/or secondary and/or tertiary and/or quaternary amines and/or diamines, preferably primary and/or secondary and/or tertiary and/or quaternary fatty amines and/or diamines, wherein one or more substituents on the nitrogen have a chain length of 10 to 20 carbons, preferably 10 to 18 carbons. Examples are dodecylamine, didodecylamine, didodecylmethylamine, didodecylbenzylmethylammonium chloride, or the substances dicocomethylbenzylammonium chloride, N-tallow-l,3-diaminopropane. The primary and/or secondary and/or tertiary fatty amines and/or the amines may also be present in the form of salts. As neutralization agents for the primary and/or secondary and/or tertiary amines and/or diamines, mineral acids and/or organic acids may be used, wherein formic acid and/or acetic acid are preferably employed. Another example of a microbicidal agent is tributyltin benzoate. Examples of substances promoting microbicidal agents such as chelating agents, preferably nitrilotriacetic acid, ethylenediaminetetraacetic acid (EDTA), diethylene triamine pentaacetic acid (DTPA) and the alkali salts thereof as well as optionally one or more oxidation stabilizers such as 2-phosphono-l,2,4-butanetricarboxylic acid, preferably in amounts of 0.05-1.0% by wt.

In a formulation containing phenolate in an amount of 60-70% by wt.,crystallization inhibitors are preferably present in an amount of 1-3% by wt., based on the total formulation.

The phenolates contained in the formulation have microbicidal effects and therefore act as preservatives. Due to these properties, they may be used both for protective and for curative applications. The advantage of the formulation is that phenolates show no spontaneous or gradual crystallization or, at any rate, that crystallization thereof is so slow that it does not have an adverse effect.

The formulations according to the present invention have crystallization points or freezing points of at least -10°C even upon addition of seed crystals. Preferred embodiments of the formulations have crystallization or freezing points of -15°C or even -20°C.

Thus, the formulation is also characterized by containing: a) 50-80% by wt. of at least one phenolate; and b) 20-50% by wt. of a solvent system comprising 90-99.9% by wt. water and 0.Ι-ΙΟ.0% by wt. of at least one crystallization inhibitor; wherein a proportion of 1.0-4.9% by wt. of said formulation may be replaced by other microbicidal agents and/or other components.

Hence, important for the success of the present invention has been the surprising and unforeseeable effect of low amounts of alcohols, employed in an amount of 0.1-10% by wt., based on the total formulation, which unexpectedly act as crystallization inhibitors in said formulation.

In another embodiment of the present invention, the formulation contains other substances with microbicidal effects, for example compounds with bactericidal and/or fungicidal effects.

Preferably, the formulation according to the present invention contains no emulsifiers, anionic, cationic, non-ionic surfactants or wetting agents, such as lauryl sulfate, nonyl phenols, ethoxylates, fatty amines, since these components may destabilize the suspensions or dispersions of minerals, fillers, pigments and natural or synthetic organic binders and the mixtures thereof, promote foaming and/or lead to depositions.

The formulations according to the present invention contain as organic solvent components besides the phenolate preferably at most 1-10% by wt., further preferred 1-5% by wt., also preferred 1-3% by wt. of organic solvent components. Here, organic solvent components refer to the crystallization inhibitor including any further optionally contained components, such as microbicidal agents and/or substances promoting the microbicidal agents.

The preparation of the formulation according to the present invention may be performed by those skilled in the art using their expertise without any additional creativity required.. For example, for the preparation of the formulation according to the present invention, water, a neutralizing agent and a crystallization inhibitor, as well as optionally other substances, are charged into a vessel and the phenol dissolved by agitation and optionally by heating.

Principally, there are no special requirements with respect to the order of addition. However, a temporary incompatibility may occur leading to a temporary precipitation of substances. Therefore, water and the neutralizing agent are preferably added first, the phenol compounds dissolved therein, followed by the addition of the crystallization inhibitor.

Surprisingly and unexpectedly, it turned out that phenolate solutions which have been completely neutralized, preferably neutralized to 103-115 mol % with alkali hydroxide, and solutions of phenolates or of salts of phenol and the derivatives thereof, e.g. o-phenylphenolate, or salts of cresol to which 0.1-10% by wt. alcohols, based on the total formulation, have been added as crystallization inhibitor showed no crystallization even at a high solid content of more than 50% by wt. of phenolates and at very low temperatures of, for instance, -20°C even if seed crystals such as solid o-phenylphenol were added several times, the solutions were stable for months, and the brownish discoloration was less intense than for example that which is well-known from conventional aqueous solutions of alkali salts of o-phenylphenol, and the freezing point is optimal for the problem to be solved. Surprisingly, the same formulations of phenolates at phenolate concentrations of,say,only 40% by wt. are not stable against crystallization at -20°C and show spontaneous solidification.

It is also obvious from the accompanying Examples, that the formulation according to the present invention is preferably employed as a preservative, particularly preferred for the preservation of aqueous suspensions or dispersions of minerals, fillers, pigments, and natural or synthetic organic binders and the mixtures thereof. Using the formulation according to the present invention, suspensions or dispersions with a solid content of more than 40% by wt., preferably more than 60% by wt., and further preferred more than 70% by wt. may also be treated at temperatures of < -10°C without crystallization of the phenolates. Furthermore, the formulation may be employed in the preservation of cooling lubricants, preferably in the metal industry. The aqueous suspensions or dispersions of minerals, fillers and/or pigments containing the formulation according to the present invention are preferably employed in the fields of paper-making, paper coating, as well as aqueous lacquers and paints. The formulation is suitable for protective as well as curative use.

Furthermore, the aqueous suspension or dispersion may further contain one or more synthetic and/or natural organic binders, preferably styrene butadiene latices and/or styrene acrylate latices, starch and/or carboxymethylcellulose which are protected from microbial attack and/or spoilage.

As minerals and/or fillers and/or pigments, the aqueous suspension or dispersion preferably contains compounds containing elements of the second and/or third main group and/or the fourth main group and/or the fourth side group of the periodic table of elements, particularly calcium and/or silicon and/or aluminium and/or titanium and/or barium, and/or organic pigments.

Preferably, the aqueous suspension or dispersion contains minerals and/or fillers and/or pigments containing kaolin and/or aluminium hydroxide and/or titanium dioxide and/or barium sulfate and/or polystyrene hollow spheres and/or formaldehyde resins and/or calcium carbonate, particularly natural calcium carbonates and/or precipitated calcium carbonates and/or marble and/or lime and/or dolomite and/or dolomite-containing calcium carbonates.

Thus, the present invention also relates to aqueous suspensions or dispersions of minerals and/or fillers and/or pigments and/or natural or synthetic organic binders and/or cooling lubricants containing the formulation according to the present invention. The proportion of the formulation in the aqueous suspension or dispersion is preferably 100 g of the formulation/ton of good to be preserved to 2500 g of the formulation/ton of good to be preserved.

The present invention also relates to the use of the formulation according to the present invention as a preservative in an aqueous suspension or dispersion of minerals and/or fillers and/or pigments and/or natural or synthetic organic binders and/or cooling lubricants

In a preferred embodiment of the present invention, the formulation according to the present invention is employed as a preservative in metal industry, paper-making, paper coating, as well as in aqueous lacquers and paints.

In a further preferred embodiment of the present invention, the formulation according to the present invention is employed as a preservative and/or mordant in wood industry and/or forestry.

Furthermore, the present invention also relates to the method for the preparation of the formulation according to the present invention, i.e. a method for the preparation of a phenolate-containing formulation wherein water and a neutralizing agent are added first, phenol compounds dissolved therein, followed by the addition of the crystallization inhibitor. A preferred embodiment of the method is placing the crystallization inhibitor together with water and a neutralizing agent in a vessel, followed by dissolution of the phenol compounds therein.

Another preferred embodiment of the method is keeping the temperature during dissolution between 5-80°C, preferably 40-60°C.

The invention is explained in more detail below using the Examples, also in comparison with the prior art. However, the invention is not intended to be limited to these exemplary embodiments.

General remarks with respect to the Examples 1.) Germ counts

The germ count was determined according to the method "Bestimmung von aeroben mesophilen Keimen", Schweizerisches Lebensmittelbuch, chapter 56, section 7.01, edition of 1985, revised version of 1988. for the most part, the bacterial strains detected were from the family of pseudomonads (predominantly Pseudomonas aeruginosa), but grampositive germs and fungi were also present. 2. ) Measurement of the viscosity of the mineral and/or filler and/or pigment suspension

The measurement of viscosity was performed on a Brookfield viscosimeter type PVF-100 at 100 rpm. The following spindles were used for the individual measurements:

Spindle RV2 40 - 320 mPas RV3 320 - 800 mPas RV4 800 - 1600 mPas RV5 1600 - 3200 mPas RV6 3200 - 8000 mPas

The measurement was carried out in a low 400-mL beaker.

The temperature during the measurement was 20°C. The measurement was performed after stirring for 1 minute.

Prior to the actual measurements, all samples were stirred intensively for 2 minutes (5000 rpm, stirring disc diameter 50 mm).

This type of viscosity measurement was used in all of the following examples. 3. ) Fineness of the mineral and/or filler and/or pigment suspension

The fineness characteristics of the suspensions prepared according to the present invention were determined by sedimentation analysis in a gravity field using a SEDIGRAPH 5100 device by Micromeritics company, U.S.A.

The measurement of the cation-stabilized suspensions was carried out in distilled water. Dispersion of the samples was performed by means of high-speed stirrer and sonication.

Measurements on the powders were performed in a 0.1% solution of Na4P207.

The particle distribution measured was depicted on a x-y recorder as the cumulative undersize frequency curve (see for instance Belger, P., Schweizerische Vereinigung der Lack- und Farbenchemiker, XVII. FATIPEC-Kongress, Lugano, 23-28 September 1984), the x-axis representing the particle diameter of a corresponding spherical cross section and the y-axis representing the share of particles in % by weight. 4.) Preparation of the phenolate solutions

The appropriate amount of demineralized water was charged into a vessel, and the calculated amount of alkali was dissolved therein. The amount of alkali was calculated so that neutralization of the phenol to 105 mol % with potassium hydroxide was achieved, except in prior art Examples 2 and 3 where 135 mol% of potassium hydroxide was used. Subsequently, the phenol or its derivative was added in an amount corresponding to the required actives content of the solution in (% by wt.) and dissolved under agitation and heating to 50°C.

In the Examples according to the present invention, 1-10% by wt. of crystallization inhibitor was added depending on the experimental series.

No crystallization inhibitor was added in the Examples according to the prior art.

Afterwards, the solutions were stored in a freezer for at least 24 h and visually inspected for crystallization, 50-100 mg of the appropriate dry phenolate or phenol derivative were added as seed crystals, and the solutions were again inspected for crystallization at -20°C.

Prior Art Examples

Example 1, prior art

Test solution 30% by wt. OPP corresponding to 39% by wt. OPPK: 300.0 g o-phenylphenol

103.5 g KOH 596.5 g water

Test solution 50% by wt. OPP corresponding to 66.5% by wt. OPPK: 500.0 g o-phenylphenol

173.0 g KOH 327.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, the o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C.

Results:

A solution of 30% by wt. and 50% by wt., respectively, of o-phenylphenol corresponding to 39% by wt. and 66.5% by wt., respectively, of potassium o-phenylphenolate neutralized with 1.05 mols KOH per mol o-phenylphenol in distilled water partly crystallizes spontaneously and partly after storing it for 3 days at -20°C.

Upon addition of 50 mg o-phenylphenol (OPP crystals) as seed crystals, the solution spontaneously crystallizes at -20°C forming a solid mass.

In this form, the solution is unsuitable for use.

Crystallization of the solution at -20°C can only be prevented by adding a high excess of KOH.

Example 2, prior art

Test solution 20% by wt. OPP corresponding to 25% by wt. OPPNa: 200.0 g o-phenylphenol

49.4 g NaOH 750.6 g water

Water was charged into a vessel, NaOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the NaOH solution under agitation on a magnetic stirrer at 50°C.

Results:

A solution of 20% by wt. of o-phenylphenol corresponding to 24.7% by wt. sodium o-phenylphenolate neutralized with 1.05 mols NaOH per mol o-phenylphenol in distilled water showsspontaneous crystallization; the freezing point is only minus 7°C.

In this form, the solution is unsuitable for use.

Example 3, prior art

Test solution 30% by wt. OPP, corresponding to 39% by wt. OPPK: 300.0 g o-phenylphenol

133.4 g KOH corresponding to 1.35 mols KOH/mol OPP 566.6 g water

Water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C.

Result:

An aqueous slurry of kaolin from Georgia, USA, having a solid content of 72.8 % by wt. and such a grain size distribution that 94 % by wt. of the particles had a diameter of below 2 pm (as measured by Sedigraph 5100, Micromeritics, USA) dispersed with 0.35 % by wt. of sodium polyacrylate and having a pH of 7.4 was added with 300 g/t of slurry, based on 100% OPP of the above commercial 39% by wt. solution or 66.5% by wt. potassium o-phenylphenolate solution (corresponding to 300 ppm 100% OPP). A blank of the kaolin slurry was prepared in the same manner, yet without the preservative.

Results:

In the blank without the commercial potassium o-phenylphenolate, a germ count of 105/g was measured after 48 hrs.

In the sample containing 300 ppm, based on 100% OPP, of commercial potassium o-phenylphenolate, a germ count of < 100/g was measured after 48 hrs.

Upon addition of 300 ppm, based on 100% OPP, of the 39% by wt. commercial potassium o-phenylphenolate solution, the viscosity of the kaolin slurry with a high solid content dispersed with sodium polyacrylate increased immediately as well as during a storage period of 1 week.

In this case, there is a risk of not being able to unload the slurry after a several-week shipment in large quantities by ship, rail or truck. However, in order to keep the slurry sterile, it is required to use 300 ppm, based on 100% OPP, added in the form of potassium o-phenylphenolate. It is impossible to preserve the slurry without adversely affecting the other properties of the slurry.

Example 4, prior art

An aqueous slurry of calcium carbonate from natural marble obtained from Norway having a solids content of 77.8 % by wt. and such a grain size distribution that 90 % by wt. of the particles had a diameter of below 2 pm (as measured by Sedigraph 5100, Micromeritics, USA) was preserved by 250 g/t of slurry, based on 100% OPP in the form of a commercial 39% by wt. solution of potassium o-phenylphenolate as in Example 2 added drop-wise under stirring within 1 minutes. A blank of the calcium carbonate slurry was prepared in the same manner, but without preservatives.

Results:

The oversize products of the blank without commercial potassium o-phenylphenolate were 25 ppm using a screen with a mesh size of 45 pm.

The oversize products of the sample with 250 ppm, based on 100% OPP, added as the commercial potassium o-phenylphenolate were 160 ppm on a screen having a mesh size of 45 pm.

In the blank without commercial potassium o-phenylphenolate, a germ count of 105/g was measured after 48 hrs.

In the sample with 250 ppm/t, based on 100% OPP, added as the commercial potassium o-phenylphenolate, a germ count of < 100/g was measured after 48 hrs.

The viscosity of the calcium carbonate slurry having a high solid content which had been dispersed with sodium polyacrylate has not substantially increased during a storage period of 1 week. However, it was clearly visible that the oversize products of the 45 pm screen were unacceptably increased. The high concentration of salt resulted in agglomerate formation in the highly concentrated slurry. The pH of the slurry was adversely altered into the more alkaline range. A pH of more than 10 in the coating used in paper industry leads to rheology problems. Furthermore, the increase in oversize products of this product inevitably leads to scratches in the paper coat as well as to dust formation during printing.

To protect the slurry from spoilage by microorganisms, it is required to add 250 ppm, based on 100% OPP, in the form of the commercial potassium o-phenylphenolate of Example 2.

It is impossible to preserve the slurry without adversely affecting the other properties of the slurry.

Example 5, prior art

Test solution 30% by wt. + 3% monopropylene glycol: 300.0 g o-phenylphenol

103.5 g KOH 30.0 g monopropylene glycol 596.5 g water

Test solution 30% by wt. + 5% monopropylene glycol: 300.0 g o-phenylphenol

103.5 g KOH 50.0 g monopropylene glycol 546.5 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

A solution of 30% by wt. of o-phenylphenol neutralized with 1.05 mols KOH per mol o-phenylphenol corresponding to 39% by wt. potassium o-phenylphenolate in distilled water shows spontaneous crystallization at -20°C if OPP is added as seed crystals despite the addition of 3-5% monopropylene glycol.

Examples according to the present invention

Example 6

Test solution 50% by wt. + 1% monopropylene glycol: 500.0 g o-phenylphenol

173.0 g KOH 10.0 g monopropylene glycol 317.0 g water

Test solution 50% by wt. + 3% monopropylene glycol: 500.0 g o-phenylphenol

173.0 g KOH 30.0 g monopropylene glycol 297.0 g water

Test solution 50% by wt. + 5% monopropylene glycol: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g monopropylene glycol 277.0 g water

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol.

Example 7 (Comparative examples)

Test solution 50% by wt. + 1% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 10.0 g 1-butanol 317.0 g water

Test solution 50% by wt. + 3% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 30.0 g 1-butanol 297.0 g water

Test solution 50% by wt. + 5% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g 1-butanol 277.0 g water

Test solution 50% by wt. + 10% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 100.0 g 1-butanol 227.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, 1-butanol was added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of 1-butanol.

Example 8

Test solution 50% by wt. + 1% benzyl alcohol: 500.0 g o-phenylphenol

173.0 g KOH 10.0 g benzyl alcohol 317.0 g water

Test solution 50% by wt. + 3% benzyl alcohol: 500.0 g o-phenylphenol

173.0 g KOH 30.0 g benzyl alcohol 297.0 g water

Test solution 50% by wt. + 5% benzyl alcohol: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g benzyl alcohol 277.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, benzyl alcohol was added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of benzyl alcohol.

Example 9 (Comparative example)

Test solution 50% by wt. + 1% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 10.0 g 1-butanol 317.0 g water

An aqueous slurry of kaolin from Georgia, USA, having a solid content of 72.8 % by wt. and such a grain size distribution that 94 % by wt. of the particles had a diameter of below 2 pm (as measured by Sedigraph 5100, Micromeritics, USA) dispersed with 0.35 % by wt. of sodium polyacrylate and having a pH of 7.4 was added with 300 g/t of slurry, based on 100% OPP, added in the form of the above 66.5% by wt. potassium o-phenylphenolate solution. A blank of the kaolin slurry was prepared in the same manner, but without the preservative.

Results:

In the blank without potassium o-phenylphenolate, a germ count of 105/g was measured after 48 hrs.

In the sample with 300 ppm/t slurry, based on 100% OPP, added as potassium o-phenylphenolate, a germ count of < 100/g was measured after 48 hrs.

Upon the addition of 300 ppm each, based on 100% OPP, of the potassium o-phenylphenolate solution according to the present invention, the viscosity of the kaolin slurry having a high solid content dispersed with sodium polyacrylate increased only slightly. In this case, there is no risk that it may be impossible to unload the slurry after several-week shipment in large quantities by ship, rail or truck. 300 ppm, based on 100% OPP, of potassium o-phenylphenolate according to the present invention are sufficient to keep the slurry sterile. It is possible to preserve the slurry without adversely affecting the other properties of the slurry.

Example 10 (Comparative example)

Test solution 50% by wt. + 1% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 10.0 g 1-butanol 317.0 g water

An aqueous slurry of calcium carbonate from natural marble obtained from Norway having a solid content of 77.8 % by wt. and such a grain size distribution that 90 % by wt. of the particles had a diameter of below 2 pm (as measured by Sedigraph 5100, Micromeritics, USA) was preserved by 250 g/t of slurry, based on 100% OPP, of the 66.5% by wt. potassium o-phenylphenolate according to the present invention added drop-wise under stirring within 1 min. A blank of the calcium carbonate slurry was prepared in the same manner but without the preservative.

Results:

The oversize products of the blank without potassium o-phenylphenolate were 28 ppm using a screen with a mesh size of 45 pm.

The oversize products of the sample with 250 ppm, based on 100% OPP, added as the 66.5% by wt. potassium o-phenylphenolate solution according to the present invention were 38 ppm on a screen having a mesh size of 45 pm.

In the sample with 250 ppm/t of slurry, based on 100% OPP, added as potassium o-phenylphenolate according to the present invention, a germ count of < 100/g was measured after 48 hrs.

The viscosity of the calcium carbonate slurry having a high solid content which had been dispersed with sodium polyacrylate did not increase during a storage period of 1 week. The value was within the variation of the method. The oversize products of the 45 pm screen increased only minimally, which is also within the variation of the method. The lower concentration of salt in the solution according to the present invention did not result in a considerable agglomerate formation in the highly concentrated slurry. The pH of the slurry was not substantially altered into the alkaline range. Slurry preserved with the formulations according to the present invention is suitable for the paper-making industry.

To protect the slurry from spoilage by microorganisms, it is necessary to add 250 ppm, based on 100% OPP, added in the form of potassium o-phenylphenolate. By using the formulation according to the present invention, it is possible to preserve the slurry without negatively affecting the other properties of the slurry.

Example 11

Test solution 50% by wt., calculated as o-phenylphenol, + 3% monopropylene glycol:

500.0 g o-phenylphenol 86.5 g KOH 60.3 g NaOH 30.0 g monopropylene glycol 323.2 g water

In each case, water was charged into a vessel, KOH and NaOH were added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH/NaOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

A solution of 50% by wt. o-phenylphenol neutralized with 0.525 mols of KOH and 0.525 mols of NaOH per mol o-phenylphenol corresponding to about 64% by wt. potassium/sodium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol.

Example 12 (Comparative example)

Test solution 50% by wt., calculated as p-phenylphenol, + 3% 1-butanol: 500.0 g o-phenylphenol

173.0 g KOH 30.0 g 1-butanol 297.0 g water

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at minus 15°C even upon the addition of different types of seed crystals if the crystallization inhibitor according to the present invention is added in the form of 3% by wt. 1-butanol.

Example 13

Test solution 40% by wt. + 10% each of different crystallization inhibitors:

400.0 g o-phenylphenol 138.4 g KOH 100.0 g monopropylene glycol or 1-butanol or benzyl alcohol 361.6 g water

In each case, water was charged into a vessel, KOH were added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, the crystallization inhibitor was added.

Results:

A solution of 40% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 53% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -10°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol or 1-butanol or benzyl alcohol.

Example 14

Test solution 50% by wt. + 5% monopropylene glycol:

500.0 g phenol 312.8 g KOH 50.0 g monopropylene glycol 137.2 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, phenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

Example 15

Test solution 50% by wt. + 5% monopropylene glycol: 500.0 g o-cresol

272.2 g KOH 50.0 g monopropylene glycol 177.8 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-cresol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

Example 16

Test solution 50% by wt. + 5% monopropylene glycol + 0.2% oxidation inhibitor: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g monopropylene glycol 2.0 g 2-phosphono-l,2,4-butanetricarboxylic acid 275.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol and the oxidation stabilizer were added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol. The properties of the formulation are not adversely affected by the oxidation stabilizer.

Example 17

Test solution 50% by wt. + 5% monopropylene glycol + 0.05% chelating agent: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g monopropylene glycol 0.5 g ethylenediaminetetraacetic acid - disodium salt (EDTA) 276.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol and the chelating agent were added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -20°C even upon the addition of OPPas seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol. The properties of the formulation are not adversely affected by the chelating agent.

Example 18

Test solution 50% by wt. + 5% monopropylene glycol + 1% of a substance promoting the biocidal effect: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g monopropylene glycol 10.0 g peptone 267.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol and the substance promoting the biocidal effect were added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -15°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol. The properties of the formulation are not adversely affected by the peptone.

Example 19

Test solution 50% by wt. + 7% monopropylene glycol + 3% of another substance with a biocidal effect: 500.0 g o-phenylphenol

173.0 g KOH 70.0 g monopropylene glycol 50.0 g N-tallow-l,3-diaminopropane 207.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol and the additional substance with a biocidal effect were added.

Results:

A solution of 50% by wt. of o-phenylphenol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 66.5% by wt. potassium o-phenylphenolate in distilled water shows no crystallization at -15°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol. The properties of the formulation are not adversely affected by the additional biocide.

Example 20

Test solution 50% by wt. + 3% monopropylene glycol + 500.0 g trichlorophenol

150.0 g KOH 30.0 g monopropylene glycol 320.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, trichlorophenol was added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

A solution of 50% by wt. of trichlorophenol neutralized with 1.05 mols of KOH per mol trichlorophenol corresponding to 60% by wt. potassium trichlorophenolate in distilled water shows no crystallization at -15°C even upon the addition of OPP as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol.

Example 21

Test solution 50% by wt. + 5% monopropylene glycol + 5% of an additional substance with a biocidal effect: 500.0 g o-phenylphenol

173.0 g KOH 50.0 g monopropylene glycol 50.0 g sodium salicylate 227.0 g water

In each case, water was charged into a vessel, KOH was added and dissolved under agitation on a magnetic stirrer within 5 min. Afterwards, o-phenylphenol and the additional substance with biocidal effect were added and dissolved in the KOH solution under agitation on a magnetic stirrer at 50°C. Finally, monopropylene glycol was added.

Results:

Example 22

Test solution 50% by wt. + 5% monopropylene glycol:

500.0 g o-cresol 174.9 g KOH 50.0 g monopropylene glycol 275.1 g water

Results:

A solution of 50% by wt. of o-cresol neutralized with 1.05 mols of KOH per mol o-phenylphenol corresponding to 61.6% by wt. o-cresol potassium salt in distilled water shows no crystallization at -15°C even upon the addition of o-cresol as seed crystals if the crystallization inhibitor according to the present invention is added in the form of monopropylene glycol.

Claims

1. An aqueous, fenolat-containing liquid formulation having a solidification point of less than or equal to -10 ° C, characterized in that the formulation contains the following components: a) 50-80 weight percent of one or more fenolater; b) 0.1-10 weight percent of at least one crystallization inhibitor selected from one or more aliphatic glycol compounds such as ethylene glycol, monopropylene glycol and / or diethylene glycol, and / or benzyl alcohol, 2-phenylethane-l-ol, 3-phenyl-propan-l-ol and / or l-phenyl-propan-2-ol; and the difference for each 100 weight percent, of an excess of alkali to 0.03 to 0.15 mol / mol, and water.

2. The formulation of claim 1, characterized in that it contains, as fenolaterne, salts of phenols and / or fenolater containing one or more aliphatic and / or aromatic substituents.

3. The formulation of claim 1 or 2, characterized in that it contains, as fenolaterne, o-phenylfenolater and / or halogenated fenolater and / or kresolsalte and / or salts of halogenated cresols and / or resorcinolsalte.

4. A formulation according to any one of claims 1 to 3, characterized in that it contains fenolaterne in an amount of 50-75 weight percent, preferably 55-70 percent by weight, and further preferably 60-70 or 62-67 weight percent.

5. A formulation according to any one of the preceding claims, characterized in that it contains krystalliseringsinhibitorerne in an amount of 0.5-5 percent by weight, preferably 1-3 percent by weight.

6. A formulation according to any one of the preceding claims, characterized in that the added microbiocidal agent which contains, organometallic compounds and / or quaternary ammonium compounds, and / or complexing agent as a microbiocidal agent-supporting substance and / or antioxidants (oxidationsstabiliseringsmidler).

7. A formulation according to any one of the preceding claims, characterized in that said microbicidal agent contains dicocomethylbenzylammoniumklorid and / or tributyltinbenzoat and / or N-tallow-l, 3-diaminopropane.

8. A formulation according to any one of the preceding claims, characterized in that it contains the complexing agent NTA and / or EDTA and / or DTPA, and / or 2-phosphono-l, 2,4-butanetricarboxylic acid as antioxidant, each preferably in a quantity of 0.05-1 weight percent based on the formulation.

9. A formulation according to any one of the preceding claims, characterized in that the formulation contains: a) 50-80 weight percent of at least one fenolat; and b) 20-50 weight percent of the solvent system comprising 90-99 weight percent water and from 0.1 to 10.0 weight percent of at least one crystallization inhibitor; wherein a portion of from 1.0 to 4.9 weight percent of the formulation may be replaced by additional microbicidal agents and / or compounds which promote these agents.

10. A formulation according to any one of the preceding claims, characterized in that the fenolaterne is present in the form of the potassium salt or the potassium and sodium salts and / or potassium and litiumsaltene.

11. A formulation according to any one of the preceding claims, characterized in that from 1.03 to 1.15, preferably 1.05 to 1.10 moles of alkali per mole of fenolat have been used for neutralization.

12. A formulation according to any one of the preceding claims, characterized in that the krystalliseringsinhibitorerne is present in an amount of 1-3 percent by weight in a formulation which contains 60-70 percent by weight of fenolat.

13. An aqueous suspension or dispersion of minerals and / or fillers and / or pigments and / or natural or synthetic organic binders and / or cooling lubricants containing a formulation according to any one of the preceding claims.

14. Suspension or dispersion according to claim 13, characterized in that the formulation is present in an amount of 100 g / t to 2500 g / ton of suspension or dispersion.

15. Use of a formulation according to any one of the preceding claims as a preservative in an aqueous suspension or dispersion of minerals and / or fillers and / or pigments and / or natural or synthetic organic binders and / or cooling lubricants.

16. Use according to claim 15, characterized in that the preservative used in the metal industry, in paper making, paper coating, in aqueous lacquers and in paints.

17. Use of a formulation according to one or more of claims 15 and 16, as a preservative, characterized in that the formulation is used as a preservative and / or a mordant in the timber industry and / or in forestry.

18. A process for the preparation ofa fenolat-containing formulation according to any one of the preceding claims, characterized in that water and a neutralizing agent is placed in a vessel, and that fenolforbindelserne dissolved therein, and then crystallization inhibitor is added.

19. A method according to claim 18, characterized in that the crystallization inhibitor is placed together with the water and the neutralizing agent in a vessel, and then fenolforbindelsen dissolved therein.

20. The method of claim 18 or 19, characterized in that the temperature during dissolution is 5-80 ° C, preferably 40-60 ° C.