DE102010031094A1 - Use of esterquats and/or amidoquats as additives in coolants for processing glass, silicon or carbides - Google Patents

Abstract

Use of esterquats and/or amidoquats as additives in coolants for processing glass, silicon or carbides, is claimed. Independent claims are also included for: (1) a concentrate comprising at least one compound (I) or (II) or their mixtures, which is used as a coolant during the processing of glass, silicon or carbides; (2) a coolant comprising the above concentrate (0.005-less than 5 wt.%) in water, and further additives, where the sum of weights of all components is 100 wt.%; and (3) processing glass-, carbide-, or silicon surfaces, comprising using the above coolant.

Description

The invention relates to surfactants, in particular cationic surfactants for use in cooling lubricants for glass processing.

Under glass is a solid at room temperature melt of silica (SiO ₂ ), calcium oxide (CaO), sodium oxide (Na ₂ O) containing optionally some larger amounts of boron trioxide (B ₂ O ₃ ), alumina (Al ₂ O ₃ ), lead oxide (PbO), magnesium oxide (MgO), barium oxide (BaO), potassium oxd (K ₂ O) and other additives understood (Source: Römpp Online Version 3.6 ( http://www.roempp.com )). In most cases, the glass is in the amorphous, non-crystalline state. However, there are also crystalline substances which are referred to by the expert as glass. An example is the quartz glass, which consists of pure SiO ₂ Furthermore, silicon in (poly) crystalline morphology with a surface of SiO ₂ and selected carbides such as silicon carbide (SiC) are among the substances considered here. Organic glasses, such as acrylic glass are not the subject of the present invention.

For the processing of such materials the use of a cooling lubricant is absolutely necessary. Examples of such machining processes are (separation) grinding, milling or drilling. The task of the cooling lubricant is to reduce the friction between two surfaces which are in relative movement with respect to one another and to dissipate the resulting frictional heat. Furthermore, the Abschliff should be removed. The wear of the tools should be kept as low as possible, this should be achieved by low friction between the tool and material to be machined. The corrosion of the tools should be prevented. Such a cooling lubricant is also referred to in the context of this invention as a functional fluid.

For reasons of environmental protection, aqueous media are nowadays used almost exclusively for processing glass. Apart from water, such coolants contain emulsified oil as the basic component and polyhydric alcohols, such as, for example, ethylene glycol, 1,2-propylene glycol or glycerol. In addition, various alkanolamines, anionic and nonionic surfactants are used. Examples of such cooling lubricants can be found in the publications US 3,453,784 and US 3,715,312 , Such coolants are not dissimilar in structure to the aqueous coolants developed for metal working. The effect of such coolants is due in part to the fact that the surfactants adsorb to the interface at metal. This boundary layer reduces the energy required for machining and provides the necessary lubrication.

The adsorption of ionic surfactants at interfaces is due to the Coulomb interaction between the charged head group of the surfactant and the charge at the interface. In this context, the pH of the cooling lubricant plays a crucial role. Metallic surfaces such as steel and aluminum are usually positively charged to high pH levels. The isoelectric point, ie, the pH at which the total charge on the surface is zero, is, for example, at pH 10 for aluminum. At values below pH 10, the resulting charge on the aluminum surface is positive. Negatively charged, anionic surfactants therefore have the ability to adsorb at the interface and form an interface. For example, the effect of anionic surfactants as corrosion inhibitors in metalworking is based on this adsorption. For glass, however, the isoelectric point is at very low pH. For example, silica (amorphous SiO ₂ ) has its isoelectric point between pH 1 and 2 ( Source: Colloidal Silica: Fundamentals and Applications, Surface Science Series Vo. 131; HE Bergna, WO Roberts (Eds.), Taylor & Francis 2006, p. 273 ). Above this isoelectric point, the resulting charge is negative. Anionic surfactants therefore experience a repulsive interaction and are unable to form a protective layer. In contrast, the cationic surfactants.

The argument can be repeated in principle for other materials. As soon as the pH of the cooling lubricant is above the isoelectric point of the material, adsorption of cationic surfactants is possible in principle. This is the case for silicon, the surface of which is covered by a silicon oxide layer which prevents further oxidation of the silicon. This is also the case for carbides such as silicon carbide whose isoelectric point is at pH 2.3 ( Source: W. Li, P. Chen, M. Gu, Y. Jin: Effect of TMAH on rheological behavior of SiC aqueous suspension, Journal of the European Ceramic Society 2004, Vol. 24, pp. 3679-3684 ).

Cationic surfactants also adsorb on organic materials such as cotton. For example, the use of cationic surfactants as fabric softeners is based on this adsorption. This adsorption is also made possible by the pH-dependent surface charge of bleached cellulose.

wobei R einen Kohlenwasserstoffrest mit 12 bis 18 C-Atomen, und X vorzugsweise ein Methosulfatanion ist.In glass processing, the use of cationic surfactants in coolants is the state of the art DD 257,270 Describe winds, glatzel and walnut Aqueous cooling and rinsing medium for the grinding and cutting process of glass. The medium is characterized by the use of cationic surfactants having the following structure,

wherein R is a hydrocarbon radical having 12 to 18 carbon atoms, and X is preferably a Methosulfatanion.

In Scripture DD 262,016 Wind, Glatzel and Nussbaum describe an aqueous cooling and rinsing medium for the grinding and cutting process of glass. The medium is characterized by the use of quaternized, ethoxylated or propoxylated fatty amines having 12 to 22 carbon atoms in the hydrocarbon radical.

wobei R einen Kohlenwasserstoffrest mit 12 bis 18 C-Atomen ist, in Kombination mit sogenannten Sulfamidocarbonsäuren.In Scripture DD 293,365 Wind, Glatzel, Landbeck and Nussbaum describe an aqueous cooling and rinsing medium for the grinding and cutting-off process of glass. The medium is characterized by the use of cationic surfactants having the following structure,

wherein R is a hydrocarbon radical having 12 to 18 carbon atoms, in combination with so-called sulfamidocarboxylic acids.

wobei R einen Kohlenwasserstoffrest mit 10 bis 20 C-Atomen ist, oder folgender Struktur,

wobei R ebenfalls ein Kohlenwasserstoffrest mit 10 bis 20 C-Atomen ist. Der Einsatz von kationischen Tensiden allerdings dient lediglich der erleichterten Reinigung der Werkstücke nach der Bearbeitung. Ein Hinweis darauf, dass der Einsatz von kationischen Tensiden den Bearbeitungsprozess an sich erleichtert, kann der Schrift EP 0 164 053 nicht entnommen werden.In Scripture EP 0 164 053 Frieser and Jainschig describe an aqueous cooling and rinsing medium for the processing of glass. The medium is characterized by the use of cationic surfactants having either the following structure,

wherein R is a hydrocarbon radical having 10 to 20 carbon atoms, or the following structure,

wherein R is also a hydrocarbon radical having 10 to 20 carbon atoms. However, the use of cationic surfactants merely serves to facilitate the cleaning of the workpieces after processing. An indication that the use of cationic surfactants facilitates the processing process itself, the font EP 0 164 053 not be removed.

On Pp 49-58 of Tribology Series 36: Lubrication at the Frontier (Eds .: D. Dowson, M. Priest, CM Taylor, P. Ehret TH C: Childs, G. Dalmaz, Y. Berthier, L. Flamand, J.-M. Georges, AA Lubrecht Elsevier 1999) " Describe Adams, Briscoe, Gorman, Hollway and Johnson the lubrication of glass-glass contacts by mixtures of cationic surfactants and fatty alcohol. The authors describe a strong increase in the friction energy for alkyl chains with less than 14 C atoms. An indication that the use of these mixtures of cationic surfactants and fatty alcohol facilitates the lubrication of contacts between glass and other materials - which is essential for the machining process because the tools are not made of glass - can not be found in this document. An indication that these mixtures of cationic surfactants and fatty alcohol can be used in the processing of glass, can also not be found in this document.

In Scripture EP 1 726 635 describe Hoetzel, Habeck and Perathoner a method for separating glass and suitable cutting fluid, in which a generated on the glass scratch is wetted with an aqueous solution containing quaternary ammonium compounds with a hydroxyl ion as counterion. This method is intended to reduce the force necessary to separate the glass. In particular, this method should be advantageous if a laser beam is used for shaving. Evidence that the use of quaternary ammonium compounds with a hydroxyl ion as Gegenion other processing steps, as well as (separation) grinding, grinding or drilling easier can not be found in this document. In addition, the use of highly corrosive by the hydroxyl ions liquids during glass processing, both for safety reasons and for corrosion protection reasons are not recommended.

Further examples of cationic surfactants are primary, secondary or tertiary amines and their Salts. In the neutral or acidic pH range, the amine group is present as a positively charged ammonium group and could therefore adsorb to glass. For coolants whose pH is in the neutral or acidic range, the use of such primary, secondary or tertiary amines is an alternative to the previously described quaternized ammonium compounds. However, coolants are generally rendered alkaline by the addition of alkanolamines, such as monoethanolamine or triethanolamine. The addition of alkanolamine serves to both inhibit corrosion and inhibit bacterial growth.

In the context of increasing environmental awareness, however, the previously mentioned types of cationic surfactants have come increasingly under criticism in recent years because of their tendency to adsorb to biological tissues and sometimes high residence times in the environment. Therefore, novel cationic surfactants have been developed, which are characterized by an improved biodegradability. An example of this are the so-called ester quats, which are described inter alia by Kruger, Bolterdorf and Overkempe (in: Surfactant Science Series, Vol. 114: Novel Surfactants, Krister Holmberg (Ed.), Marcel Dekker, New York, 2003, p. 115 ev ). Ester quats are characterized by an easily cleavable ester linkage between positively charged headgroup and apolar alkyl chain, which explains the improved biodegradability. Another example is the so-called amido quats, in which the ester bond has been replaced by an amide bond.

Esterquats and amidoquats have been used mainly for the treatment of textiles. A reference to the fact that esterquats and amidoquats are used in the processing of glass can not be taken from the document mentioned in the penultimate paragraph or other documents.

The object of the present invention was therefore to provide alternative cationic surfactants as additives in cooling lubricants for glass processing, which preferably do not have one or more of the disadvantages of the cationic surfactants known in the prior art and are biodegradable.

Surprisingly, it has now been found that esterquats and amidoquats are outstandingly suitable as additives in cooling lubricants for glass processing.

The present invention therefore relates to the use of esterquats and / or amidoquats as an additive in cooling lubricants for the treatment of glass, silicon or carbides.

wobei
R¹ und R² gleich oder verschieden eine Methyl-, Ethyl-, Propyl-, Isopropyl oder (C₂H₄-O)_n-H Gruppe ist mit n ≤ 10,
R³ und R⁴ gleich oder verschieden eine (CH₂)_n oder (C₂H₄-O)_n Gruppe ist mit n ≤ 5,
R⁵ und R⁶ gleich oder verschieden ein gesättigter oder ungesättigter, linearer oder verzweigter Kohlenwasserstoffrest mit 5 bis 30 Kohlenstoffatomen ist, und
X^– ein organisches oder anorganisches Anion ist, bevorzugt ein einwertiges organisches oder anorganisches Anion,
Y NH oder O, bevorzugt NH ist,
mit der Maßgabe, dass X kein Hydroxylion ist
bei der Bearbeitung von Glas, Silicium oder Carbiden.Another object of the present invention is the use of additives in the form of esterquats and / or amido quats of the general formula (I) or (II),

in which
R ¹ and R ^{2 are} identical or different and denote a methyl, ethyl, propyl, isopropyl or (C ₂ H ₄ -O) _n -H group with n ≦ 10,
R ³ and R ^4, equal or different, are a (CH ₂ ) _n or (C ₂ H ₄ -O) _n group with n ≤ 5,
R ⁵ and R ^6, identically or differently, are a saturated or unsaturated, linear or branched hydrocarbon radical having 5 to 30 carbon atoms, and
X ^{- is} an organic or inorganic anion, preferably a monovalent organic or inorganic anion,
Y is NH or O, preferably NH,
with the proviso that X is not a hydroxyl ion
when working on glass, silicon or carbides.

The additives according to the invention can be used alone or in mixtures with one another.

The present invention likewise relates to the use of the additives according to the invention in cooling lubricants which come into contact with surfaces such as glass, carbides such as silicon carbide SiC, tungsten carbide WC or magnesium carbide MgC or the oxidized surface of silicon.

Often the additives of the formula I and II are mixtures of compounds in which the radicals R ⁵ and R ^{6 are} different saturated and / or unsaturated, branched and / or are linear alkyl radicals having 6 to 24 carbon atoms. Particularly preferred are the mixtures of compounds in which R ⁵ and R ^{6 are} saturated and / or unsaturated, branched or linear alkyl radicals having a mode (major proportion) of distribution of the number of carbon atoms in radicals R ⁵ and R ⁶ of 8 to 22, preferably from 10 to 20, and preferably from 12 to 18. Particularly preferred are the mixtures of compounds in which the radicals R ⁵ and R ^{6 are} different saturated or unsaturated linear alkyl radicals having 6 to 24 carbon atoms, wherein the molar ratio of the alkyl radicals is dependent on the fatty acid source used. Particular preference is given to fatty acids based on natural tallow fat, hardened tallow fat, palm fat, coconut fat, tall oil, rapeseed oil and / or castor oil. It is also possible to use mixtures of these fatty acids.

Preferred radicals R ⁵ and R ⁶ are identical or different oleic, behenic, stearic, palmitic or isostearic acid radicals in the preparation of the inventive additives of the formula I and II.

The additives of the formula I and II according to the invention preferably have an organic or inorganic anion X ^- , preferably a monovalent anion, with the premise that X ^{- must} not be a hydroxyl ion. Preferably, the additives of the invention are compounds of formula I or II, in which X ^- is a halide, formate, acetate, methosulfate or Ethosulfation is preferred as the halide ion is chloride. However, the anion is preferably an organic anion, particularly preferably the anion is not a halide, if the substances to be processed or the processing means themselves are susceptible to corrosion.

The additives of the invention may be as a concentrate solid or waxy in their consistency, but can be dissolved in water or dispersed or emulsified. In particular, polyhydric alcohols may be used for emulsification or dissolution.

The functional fluids for the surface treatment according to the invention may be composed differently. They can be present as a concentrate or as a ready-to-use mixture. From the concentrate, the ready-to-use functional liquid can be obtained simply by adding the desired amount of water. The functional fluid as a cooling lubricant may be a homogeneous solution or else a suspension or dispersion of the surfactant according to the invention.

Aside from water, such coolants contain emulsified oil as the basic component and polyhydric alcohols such as ethylene glycol, 1,2-propylene glycol or glycerol. In addition, various alkanolamines, anionic and nonionic surfactants are used. By adding polyhydric alcohols, the surfactant of the invention can be solubilized and kept in solution upon dilution to the use concentration.

Preferred functional fluids, in particular ready-to-use functional fluids in the form of the cooling lubricant, comprise water and 0.005 to <5% by weight, preferably 0.25 to 1% by weight, of the additives according to the invention and may optionally contain further additives. The sum of the constituents of the functional fluid adds up to 100% by weight in each case. The pH of the ready-to-use solutions or emulsions of the functional fluids according to the invention should generally be higher than the isoelectric point of the material to be processed. Therefore, the pH at room temperature is between 3 and 11, preferably 6 to 10.5 and especially 7 to 10.

Further objects of the invention emerge from the claims, the disclosure content of which is fully the subject of the description of this invention. The surfactants for glass processing according to the invention are described below by way of example, without the invention being restricted to these exemplary embodiments. Given below, ranges, general formulas, or classes of compounds are intended to encompass not only the corresponding regions or groups of compounds explicitly mentioned, but also all sub-regions and sub-groups of compounds obtained by removing individual values (ranges) or compounds can be. If documents are cited in the context of the present description, their contents are intended to form part of the disclosure content of the present invention. Be in the context of the present invention, compounds such. Example, the surfactants of the invention described, which may have several units repeatedly, they may be randomly distributed (statistical oligomer) or ordered (block oligomer) occur in these compounds. Information on the number of units in such compounds is to be understood as an average, averaged over all corresponding compounds. Percentages (%) are by weight unless otherwise specified.

The invention is based on the 1 to 5 explained in more detail, without which the invention should be limited thereto.

In the following examples, the present invention is described by way of example, without the invention, the scope of which is apparent from the entire description and the Claims, to those mentioned in the examples. Embodiments should be limited.

Examples:

Tribological measurements:

The Stribeck curve represents the coefficient of friction between 2 sliding surfaces as a function of speed at a given pressure. At high speeds, one generally speaks of hydrodynamic lubrication. The sliding parts are separated by a liquid layer. The hydrodynamic pressure is then at least as great as the external pressure. The coefficient of friction in this area is essentially dependent on the viscosity of the lubricant. With decreasing speed, the hydrodynamic pressure is no longer sufficient to separate the moving parts. It comes to partial contact (mixed friction area), or in the worst case to complete contact of the surfaces. The result is mechanical wear. In the Stribeck curve this is indicated by strongly increasing friction coefficients. The additive according to the invention reacts with the glass surface and evidently forms adsorption layers. These adsorption layers reduce the friction of the contacting surfaces and thus increase the life of expensive tools such as drills or grinding tools. Furthermore, the frictional heat is reduced, which leads to an increase in quality of the products and also increases the life of the tools.

Stribeck curves were measured using a MTM tribometer from PCS Instruments (London, United Kingdom). A standard 3/4 "steel ball made of AISI 52100 steel was used. Also used was a 46 mm pane of borosilicate float glass. The test fluid is added to the test reservoir of the MTM until the ball and disc are completely covered with liquid. The steel ball is now pressed with a defined force on the glass. The rotational speed of disc and ball are independent. While measuring a Stribeck curve, the mean velocity becomes v = (v _disc + v _ball ) / 2 varies systematically, the sliding-roll ratio remains unchanged. The sliding-roll ratio (GRV) or slide-roll ratio (SRR) is defined as follows,

For all measurements shown here, the sliding-roll ratio was 50%. The mean velocity was logarithmically varied between 5 and 2500 mm / s. The steel ball was pressed onto the glass plate with a force of 5N. The measuring cell was kept at 33 ° C during the measurement. The same Stribeck turn is run ten times in a row, five times each with increasing speed and five times with decreasing speed. However, if the friction coefficient exceeds a critical value, the measurement is automatically canceled.

The surfaces of the glass plate and steel ball were extensively cleaned with a cleaning agent (Pril) before each measurement. Subsequently, the glass plate and steel ball were successively rinsed with water and isopropanol and dried with compressed air. Finally, glass plate and steel ball were flamed by means of a gas flame to remove any remaining organic contaminants.

The cationic surfactants employed are commercially available from Evonik Goldschmidt GmbH as Varisoft ^® 300 (cetyltrimethylammonium chloride, not of the invention), Rewoquat ^® W325PG (poly (oxy-1,2-ethanediyl), α- [2- [methylbis [2- ( 1-oxoisooctadecyl) amino] ethyl] ammonia] ethyl] -ω-hydroxy-, methyl sulfate, according to the invention), Rewoquat ^® WE18 (triethanolamine N-methyldistearat, chloride, according to the invention) and Varisoft ^® PATC (Palmamidopropyltrimethylammonium chloride, according to the invention). The solutions were heated to 60 ° C and then stirred on a magnetic stirrer. The concentration of the cationic surfactant was 0.25% by weight, based on the active content of the particular surfactant.

Example 1:

The Stribeck curve of steel on glass immersed in pure water is in 1 The friction coefficient reaches very high values up to about 1. After the second Stribeck curve, the measurement was aborted due to excessive friction values.

Example 2 (not according to the invention):

The Stribeck curve of steel on glass in a 0.25% by weight aqueous solution of cetyltrimethylammonium chloride is in 2 A total of 3 curves were measured until the crash. The friction values are considerably lower compared to pure water. So it comes to deposition of the surfactant on the glass surface and formation of a protective layer On the other hand, the values increase with each measurement, which indicates increasing damage and surface roughness.

Example 3 (according to the invention):

The Stribeck curve of steel on glass in a 0.25 wt .-% aqueous solution of Rewoquat ^® W325PG is in 3 displayed All 10 curves were measured without interrupting the measurement. The friction values are significantly lower compared to pure water and the 0.25 wt .-% solution of cetyltrimethylammonium chloride again. The friction values do not increase with each measurement, but remain constant or even decrease within the measurement error. This indicates a structural reorganization at the interface, but not damage. After the measurement, the steel ball is intact.

Example 4 (according to the invention):

The Stribeck curve of steel on glass in a 0.25 wt .-% aqueous solution of Rewoquat ^® WE18 is in 4 shown. All 10 curves were measured without stopping the measurement. The friction values are even lower compared to pure water, the 0.25% solution of cetyltrimethylammonium chloride and even the 0.25% solution of Rewoquat W325PG. The friction values do not increase with each measurement, but remain constant or even decrease within the measurement error. This indicates a structural reorganization at the interface, but not damage. After the measurement, however, the steel ball started running strongly. This is probably related to the high concentration of chloride ions that are highly corrosive.

Example 5 (according to the invention):

The Stribeck curve of steel on glass in a 0.25 wt .-% aqueous solution of Varisoft ^® PATC is in 5 displayed All 10 curves were measured without interrupting the measurement. The friction values are significantly lower compared to pure water and the 0.25 wt .-% solution of cetyltrimethylammonium chloride. The friction values remain constant within the measuring error or increase only slightly. This indicates a structural reorganization at the interface, but not damage. After the measurement, however, the steel ball started running strongly. This is probably related to the high concentration of chloride ions that are highly corrosive.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 3,453,784 [0004]
• US 3715312 [0004]
• DD 257270 [0008]
• DD 262016 [0009]
• DD 293365 [0010]
• EP 0164053 [0011, 0011]
• EP 1726635 [0013]

Cited non-patent literature

• http://www.roempp.com [0002]
• Source: Colloidal Silica: Fundamentals and Applications, Surface Science Series Vo. 131; HE Bergna, WO Roberts (Eds.), Taylor & Francis 2006, p. 273 [0005]
• Source: W. Li, P. Chen, M. Gu, Y. Jin: Effect of TMAH on rheological behavior of SiC aqueous suspension, Journal of the European Ceramic Society 2004, Vol. 24, pp. 3679-3684 [0006]
• Pp 49-58 of Tribology Series 36: Lubrication at the Frontier (Eds .: D. Dowson, M. Priest, CM Taylor, P. Ehret TH C: Childs, G. Dalmaz, Y. Berthier, L. Flamand, J.-M. Georges, AA Lubrecht Elsevier 1999) " [0012]
• Surfactant Science Series, Vol. 114: Novel Surfactants, Krister Holmberg (Ed.), Marcel Dekker, New York, 2003, p. 115 ev [0015]

Claims (12)

Use of esterquats and / or amidoquats as an additive in cooling lubricants for the treatment of glass, silicon or carbides. Use according to claim 1, characterized in that compounds of the general formula (I) or (II) are used as additives,

wherein R ¹ and R ^{2 are the} same or different and are a methyl, ethyl, propyl, isopropyl or (C ₂ H ₄ -O) _n -H group where n ≤ 10, R ³ and R ^{4 are the} same or different (CH ₂ ) _n or (C ₂ H ₄ -O) _n group with n ≤ 5, R ⁵ and R ^{6 is the} same or different and is a saturated or unsaturated, linear or branched hydrocarbon radical having 5 to 30 carbon atoms, and X ^{- is} an organic or is inorganic anion, and Y is NH or O, with the proviso that X is not a hydroxyl ion. Use according to claim 2, characterized in that the additives of the formula I and II are mixtures of compounds in which the radicals R ⁵ and R ^{6 are} different saturated and / or unsaturated, branched and / or linear alkyl radicals having 6 to 24 carbon atoms. Use according to Claim 2 or 3, characterized in that the additives of the formula (I) or (II) have identical or different oleic, behenic, stearic, palmitic or isostearic acid radicals as R ⁵ and / or R ⁶ . Use according to at least one of claims 2 to 4, characterized in that the additives of the formula (I) or (II) have a monovalent anion X ^- . Use according to at least one of Claims 5, characterized in that the additives of the formula (I) or (II) have no halide as anion X ^- . Use according to at least one of claims 2 to 4, characterized in that the additives of the formula (I) or (II) methosulfate, ethosulfate, formate or acetate as anion X ^- have. Use according to at least one of claims 2 to 7, characterized in that Y = NH. Use according to at least one of claims 2 to 8, characterized in that the carbides are selected from the group of tungsten carbide, silicon carbide and magnesium carbide. Concentrate containing at least one compound of the formula (I) or (II) or mixtures thereof for use as a cooling lubricant in the treatment of glass, silicon or carbides. Cooling lubricant containing 0.005 wt .-% to <5 wt .-% of the concentrate according to claim 9 in water and other additives, wherein the sum of all components added to 100 wt .-%. Process for the treatment of glass, carbide or silicon surfaces, characterized in that the machining takes place using a cooling lubricant according to at least one of claims 10 or 11.

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