DE202009018507U1 - Low Viscosity to High Viscosity Water Based Lubricant Composition - Google Patents

Abstract

Single-phase, low-viscosity to high-viscosity adjusted water-based lubricant composition having an average water content of> 80 wt .-%, characterized in that the lubricant composition is mineral oil-free and contains at least one polymeric lubricant which is water-soluble in the temperature range between 10 ° C and 90 ° C.

Description

The invention relates to the field of tribology, especially the structure and uses of lubricants mainly for metal cutting and high performance grinding, especially for carbide machining and takes priority German patent application 10 2008 011 781.1 of 28 February 2008.

The DIN 51502 and especially the DIN 51385 generally define lubricants and especially cooling lubricants for metalworking:
Lubricant: A liquid, plastic-solid, solid or gaseous medium which has the task of reducing friction and wear when sliding or rolling contact between two points, lines or surfaces moving together. To DIN 51502 The lubricants are divided into different groups that can be differentiated.

Lubricants in the narrower sense of the present invention are understood in particular as meaning substances or substance mixtures which bring about a reduction in the friction of the base fluid (here: water) which, in order to improve the tribological load capacity, increases the surface pressure by at least 10 N / mm ² , an increase in the specific surface pressure by at least 1,000 N / cm ² and / or an increase in the load by at least 1,000 N good load. These properties can be determined by methods known to the person skilled in the art, for example with Brugger wear test stand, Reichert friction wear balance and shell four-ball apparatus (VKA).

Coolant: According to this classification, coolants are listed as oils. The DIN 51385 defines those substances as cooling lubricants, which are used for cooling and lubricating during cutting and partly during the forming of materials, in particular of metals.

In the group of coolants are the so-called. Water-miscible cooling lubricants (called concentrates), which are mixed with water before use and the group of so-called. Non-water-miscible cooling lubricants, which are used undiluted described.

The non-water-miscible cooling lubricants are predominantly made from mineral oils or ester oils, have a species-specific, for use as a lubricant for metalworking specific viscosity, which is usually between V ₄₀ ≤ 3 and 1000 mm ² / s at 40 ° C. Water-miscible cooling lubricants are in the aqueous dilution according to the application a true solution or emulsion with the outer phase of water. These aqueous dilutions have viscosities which, depending on the concentration of the concentrate in water, have viscosities of 0 <V ₄₀ ≦ 3 mm ² / s at 40 ° ° C.

The metalworking is in the DIN 8580 (Separation) subdivided among other things in the procedures:

• Cutting

According to the current state of the art, fluids having an application viscosity of V ₄₀ > 3 mm ² / s are used for metal cutting based on non-water-miscible base fluids such as mineral oil and esters or water-mixed cooling lubricants having an application viscosity of V ₄₀ <3 mm ² / s at 40 ° C.

Due to the thermodynamic data of these fluids, the technically useful cooling effect is limited to the use of low-viscosity liquids.

Grinding belongs to the 3rd subgroup of manufacturing processes (separation) DIN 8580 to the group of cutting with geometrically indefinite cutting edge ( DIN 8589 T0 ):
Urformen
reshape
Cutting: including grinding with a rotating tool
Put
coating
Change material properties

This manufacturing method is always used when high surface quality of the workpiece is required or other processing methods are not suitable due to the nature of the material. Typical examples of this are the manufacture of tools and gears for gearbox construction.

Almost exclusively, it is reduced by using coolants DIN 51385 The main tasks are the cooling of the process, the lubrication of the friction partners and the removal of the chips.

The prior art has hitherto allowed for the machining of metals and their alloys only the use of aqueous, very good cooling low-viscosity coolants or non-aqueous, medium to high viscosity, low cooling cooling lubricants.

Examples describing the state of the art

example 1

In the course of manufacturing gear wheels for gearbox production, finishing processes such as honing using mineral oil-based cooling lubricants with a viscosity of V _{40 are} approx. 10 mm ² / s at 40 ° C to the previous production chain. The early addition of the honing tools, the elaborate cleaning of the gears and the temperature development during the process mean high production costs in addition to the enormous costs for the removal of oil vapor and mist, the installation of fire and explosion protection measures and the associated insurance costs.

Example 2

High-quality solid carbide tools are mainly produced by grinding with diamond or CBN grinding tools. The use of mineral oil- or ester-based non-water-miscible cooling lubricants describes the state of the art. As a measure of the performance of this tribological concept, the time-wasting volume Q'w (mm ³ / mms) can be considered. For the manufacturing process described above, Q'w of 3-7 mm ³ / mms have been stably realized in manufacturing up to now.

The current knowledge using the basic state of the art reveals the following rule for cutting metalworking: Machining processes which predominantly impose high demands on the coolability of the lubricant are preferably realized with water-mixed cooling lubricants, while machining processes which predominantly impose high requirements on the lubricity of the lubricant Lubricating set, preferably be controlled with viscosity adjusted non-water-miscible cooling lubricants.

Thus, there is no possibility in the course of machining metalworking operations to combine the cooling ability of water with the viscosity-requiring lubricity of non-water-miscible base fluids.

Current knowledge using the basic state of the art reveals the following principle for grinding: Since very high temperatures can occur during this machining process (up to about 1000 ° C.), the lubricant's cooling capacity is extremely demanding, and thus preferably water-mixed cooling lubricants used, whose main disadvantage is to be seen in the usually too low lubricity. This fundamental contradiction between cooling and lubrication is attempted in accordance with the state of the art in that it is preferably ground with low-viscous water-immiscible cooling lubricants.

There is thus no possibility for grinding processes to combine the cooling ability of water with the viscosity-necessary lubricity of non-water-miscible base fluids.

The aim of the invention is to provide lubricants for metalworking available that uses stabilized viscosity by the cooling effect of water to improve thermally demanding machining operations with water-miscible lubricants.

To achieve this object, the invention according to claim 1 proposes a single-phase, low-viscosity to high-viscosity adjusted water-based lubricant composition having an average water content of> 80%, containing polymers. This composition is mineral oil-free and contains a polymeric lubricant that is water-soluble in the temperature range from 10 ° C to 90 ° C.

These polymers are preferably conventional thickeners, which were previously used according to the prior art only for adjusting the desired viscosity of a lubricant composition. However, it was previously unknown that these thickeners themselves have lubricant properties, d. H. that these thickeners are lubricants in the context of the invention. It follows that the lubricant compositions according to the invention respond to the necessary use of other lubricants, i. H. other lubricants than the mentioned thickeners can get along. The thickening agents may thus be the only lubricants in the lubricant composition according to the invention.

The invention makes it possible for the first time to machine high-performance tools with water-based lubricants such that significantly higher performance data (up to about 30%) can be realized. Surprisingly, the liquids according to the invention already show a significantly better tribological performance than mineral oil and water even without any addition of performance-improving additives. An exemplary comparison is given in Table 1.

Mineral oil, as the commonly used base liquid of non-water-miscible cooling lubricants, represents the reference point for the development of the novel base liquid according to the invention. Tribological test systems such. B. Reichert friction wear scale, Brugger wear test bench and shell four-ball apparatus, allow differentiation in terms of tribological properties.

Advantageous developments and preferred uses of the lubricant composition according to the invention are the subject matter of corresponding additional or subordinate claims.

The use of lubricants is decisively influenced by his abilities, u. a. to minimize the occupational health burden of the users, to exclude the risk potential through fire and explosion and to offer the least negative impact on the environment.

Mineral oil or ester-based lubricants inevitably contaminate the workplace with lubricant vapors and subject the workpieces and the environment to dangerous oil carryover. Cooling lubricants have as hazardous substances an air limit, which is determined as a sum value from portions of the vapor and the aerosol. As a lead substance hydrocarbons are determined here.

Although the tribological activity of the fluids according to the invention has been demonstrated, surprisingly, even with extreme turbulence in practical use (eg grinding), they show no tendency to atomise and form safety-relevant slippery coverings in the machine environment. There is no risk of fire or explosion due to the composition according to the invention. Due to the complete lack of mineral oil, the air limit value for cooling lubricants (10 mg / m ³ vapor and aerosol) is complied with.

For operational practice, these features mean significant cost savings, since neither special exhaust nor fire protection systems are needed.

Water-mixed coolants are susceptible to microbial attack by bacteria, fungi and yeasts. In order to achieve an economically useful service life, therefore, significant amounts of biocides (bactericides and fungicides) must be added, which u as an important side effect. a. cause allergic reactions in humans.

Thus, another object was to develop a water-based lubricant that should have as far as possible without biocides extensive bioresistance and thus in practice does not lead to odor nuisance by microbial infestation ("Monday odor").

Surprisingly, it was found that the liquids according to the invention have an extraordinary biological stability and are capable of long useful life even without the addition of biocides, without a serious change in the properties such. B. the viscosity is clear.

In aqueous systems, which are in contact with metallic surfaces, an essential task is, despite the high water content of the working fluid, which protects against corrosion To fix ingredients on the metal surface so that adequate corrosion protection is ensured. The liquids according to the invention, to which water-soluble corrosion protection components have been added, form a surface-covering film on the workpiece surface, which surprisingly offers protection against corrosion and can nevertheless easily be washed off again.

Liquids have a substance-specific viscosity, which can be changed by application of special additives; these mainly include polymers ( Ullmanns Enzyklopädie der technischen Chemie; Römps Lexikon der Chemie and Dieter Klamann "Lubricants and Related Products", Production, Properties, Application; Verlag Chemie, Weinheim, 1982; P. 84 ff ).

As is known, these polymers, which are also referred to as viscosity index (VI) improvers, have very effective action in non-water-miscible liquids, such as, for example, polymers. As mineral oils and ester oils.

When using water as a polar liquid, however, water-soluble polymers such. As cellulose derivatives, sugars, sugar derivatives, polyvinylpyrrolidone compounds successfully used.

Viscous aqueous fluids are particularly useful as coolants, if further requirements are also met, such as corrosion protection against iron, aluminum and non-ferrous metals and their alloys, tribological effectiveness in contact between the tool and workpiece, stability against microbial colonization, high rinsing and Mesh effect for the removal of abrasion and chips from the cutting zone and fulfillment of all requirements in accordance with European Chemicals Law.

By the introduction of polymers into water according to the invention, viscosities of 2-46 mm ² / s (40 ° C.) are obtained, which determine the setting of the lubricant-typical ISO viscosity classes ISO 3448 or DIN 51 519 (ISO classes from 2 to 46), as shown in Table 2.

Depending on the mixing ratios used and the choice of suitable additives, all customary ISO viscosity classes can be produced with the mixtures according to the invention. Surprisingly, the completely water-soluble polymer blends have high shear stability and stability in water and can be prepared independently of the temperature.

The addition according to the invention of anti-corrosive, lubrication, wear protection additives and wetting agents and solubilizers assures the viscous water solution of all properties which are necessary for use in metalworking.

• a) natürliche Polymere wie z. B. Polysaccharide des neutralen Scleroglucan-Typs mit Molgewichten von ca. 10⁵ Dalton (beispielsweise Biovis); anionische Polysaccharide mit Molgewichten größer 10⁶ Dalton vom Xanthan-Typ (beispielsweise NovoXan);
• b) chemisch modifizierte Polymere auf Basis von Carboxymethylcellulosen, z. B. Natrium-Carboxymethylcellulose mit Viskositäten von 10–40.000 mP·s als 2%-ige Lösung in Wasser (z. B. Walocel-Typen CRT) polyanionische Cellulose mit Viskositäten von 25–5000 mP·s als 2%-ige Lösung in Wasser (z. B. Antisol FL-Typen); weiterhin Cellulose-Typen mit unterschiedlichen Substituenten wie DTKHV oder aH 75 (Handelsbezeichnungen);
• c) synthetische Polymere wie der kationische Polyelektrolyt mit mittlerer Ladungsdichte (z. B. Zetag 7563 der Ciba-Geigy) und neutrale Polyvinylpyrrolidontypen mit Molgewichten von ca. 10⁵–10⁶ Dalton.

The polymers (thickeners) for adjusting the viscosity of the water, which can be used according to the invention are, for. B .:

• a) natural polymers such. B. polysaccharides of the neutral scleroglucan type with molecular weights of about 10 ⁵ daltons (for example Biovis); anionic polysaccharides having molecular weights greater than 10 ⁶ daltons of the xanthan type (for example NovoXan);
• b) chemically modified polymers based on carboxymethylcelluloses, z. B. Sodium carboxymethyl cellulose having viscosities of 10-40,000 mP · s as a 2% solution in water (eg Walocel grades CRT) polyanionic cellulose having viscosities of 25-5,000 mP · s as a 2% solution in Water (eg Antisol FL types); also cellulose types with different substituents such as DTKHV or aH 75 (trade names);
• c) synthetic polymers such as the cationic polyelectrolyte with medium charge density (eg Zetag 7563 from Ciba-Geigy) and neutral polyvinylpyrrolidone types with molecular weights of about 10 ⁵ -10 ⁶ daltons.

Particularly preferred is the use of thickeners (polymers) which have good solubility in water. Particularly preferred are those polymers which are soluble in both cold and warm or hot water. Within the meaning of the invention, solubility is understood to mean the following: The entry of the polymer into deionized water results in a clear, transparent, homogeneous mixture with proportionally increasing viscosity, which remains constant over time. This solubility is given in particular at about 10 ° C and 90 ° C.

In one embodiment of the invention, thickeners are used which have a solubility of at least 5% by weight of the thickening agent in water at any temperature, preferably also at 10 ° C and 90 ° C and allow a viscosity of the lubricant composition of up to 1,000 mm ² / s, if they are used as the sole lubricant component in the composition according to the invention.

In a particularly preferred embodiment of the invention, salts of modified celluloses are used. On the one hand, these are biologically stable and, on the other hand, are very soluble in water. They are therefore also easy to process. Examples of possible modified celluloses are carboxymethylcelluloses or heteroglucan structures. Particular preference is given to salts of carboxymethylcelluloses, for example the sodium salt of carboxymethylcellulose.

• a) Wasserlöslichkeit bei Temperaturen von ca. 10–90°C.
• b) Hohe Wirksamkeit des Verdickungsvermögens, d. h. geringe Einsatzmengen für die zu erreichende Viskosität.
• c) Schmierfähigkeit in Wasser in Brugger-, Reichert- und VKA-Prüfverfahren (s. oben).
• d) Hohe mikrobielle Stabilität.

The amount of possible polymeric compounds which are suitable for changing the viscosity of the water is very large. The following criteria should preferably be fulfilled:

• a) water solubility at temperatures of about 10-90 ° C.
• b) High effectiveness of the thickening power, ie small amounts used for the viscosity to be achieved.
• c) lubricity in water in Brugger, Reichert and VKA test methods (see above).
• d) High microbial stability.

Preferably, in addition to the criterion a) at least one further criterion is met.

The requirements for the physical, tribological and ecotoxicological properties of the suitable thickeners lead to the following preferred property profile: The thickener should be organic polymer having a temperature-independent solubility of at least 50 g / 1000 g of water resulting in a viscosity of at least 1000 mm ² / s (40 ° C), and a tribological improvement of the load carrying capacity of the composition according to Brugger, Reichert and VKA of at least 10%, at least 20% or preferably at least 30% compared to mineral oil-based lubricant compositions (see, for example, Table 1) and a biological Degradability after the Guideline "OECD Guidline for testing of chemicals no. 301 ' of at most 5% after 28 days.

Taking into account this preferred property profile, it is possible according to the invention to use compounds of the following group for the preparation of the composition according to the invention: natural polysaccharides of the xanthan and scleroglucan type and of the carboxymethylcellulose derivatives, in particular their salts (for example sodium salt).

The additional amounts of the water-soluble polymers used according to the invention for adjusting the viscosity of water are preferably in the range from 0.2 to 5% by weight of the aqueous phase.

To formulate the usable metal working fluid according to the invention, it may be necessary to add additional components and additives. It is noteworthy, however, that the lubricant composition according to the invention is single-phase, i. H. all compounds contained therein are water-soluble. This also applies to the functional (ie chemically non-inert) additives, d. H. These are also water-soluble. However, it is not excluded that chemically inert additives such as pigments are included in the composition.

Thus, in particular the following further components can be added to the composition according to the invention:

Corrosion protection additives up to 5%:

• Reaction products of fatty acids with at least C8 chain length with alkanolamines such as monoethanolamine, triethanolamine, diglycolamine, isobutanolamines or hydroxides such as potassium hydroxide, sodium hydroxide

Lubricity improver up to 3%:

• Water soluble ester compounds and polymeric ethylene oxide (EO) or ethylene oxide / polypropylene oxide (EO / PO) based glycol compounds

High pressure additives up to 3%:

• These are water-soluble phosphoric acid partial esters, neutralized sulfurized fatty acids and esters.

Wear protection additives up to 3%:

• Water-soluble phosphoric acid derivatives, in particular neutralized phosphoric acid partial ester derivatives

Wetting agents and emulsifiers up to 5%:

• Fatty alcohol ethoxylates with at least 5 moles EO (ethylene oxide) and ethanol ethers

Heavy metal inhibitors up to 1%:

• based on water-soluble triazole and thiadiazole derivatives

As particularly preferred heterocyclic nitrogen compounds having a particularly strong inhibitory effect z. B. 1 H-benzotriazole, 5-methylbenzotriazole, 5-carboxybenzotriazole, benzothiazole, 2-alkylbenzothiazole 2-mercaptobenzothiazole, 2-Mercaptobenzothiazolsuccinsaure be set. Further preferred heterocyclic nitrogen compounds are benzimidazole, 2-alkylbenzimidazole, 2- (5-aminopentyl) benzimidazole, benzoxazole and 2-mercaptobenzoxazole. Heterocycles with alkyl side groups reduce the water solubility and thus improve the long-term effect of the corrosion inhibitor.

The composition according to the invention usually has at least one corrosion inhibitor in addition to the thickener as lubricant component (preferably as sole lubricant component). If the composition is also to be used in particular for hard metal processing, it should possibly also have at least one heavy metal inhibitor.

Additives to improve biological stability up to 0.5%:

• Formaldehyde-releasing compounds, especially hexahydrotriazine compounds, methyl bisoxazolidine compounds; Heterocycles, in particular benzisothiazolinone compounds, sodium pyrithione and isothiazolone compounds

Defoamer up to 1%:

• Modified siloxanes or silicic acid derivatives

In the context of the present invention, at least one polyhydric alcohol may additionally be provided as a further lubricant component, which is preferably selected from the groups of polyalcohols and carbohydrates, particularly preferably from alkanediols and alkanetriols, particularly preferably glycerol and the polyethers derived therefrom, as well as glucose, arabinose , Ribulose, fructose and the derived oligo- and / or polysaccharides and their esters and ethers. The amount of the polyalcohol based on the composition may be at least 10%, preferably at least 20%, at least 30% or at least 40% or more.

The thickeners (polymer), in particular the celluloses such as carboxymethylcelluloses (in particular sodium carboxymethylcellulose) for the preparation of the compositions according to the invention, can advantageously be used in aqueous form. Most preferably, the carboxymethylcellulose, especially the sodium carboxymethylcellulose, in the form of an aqueous solution or suspension, which can be removed directly from the modification or production of the polymer - and not a dried powder of cellulose - is used for the preparation of the composition ,

When using the lubricant composition according to the invention of non-dried modified natural polymer, it is found that the viscosity of the ready-mixed lubricant composition, if necessary after addition of the additives, changes significantly less over the course of several days than is the case when a dry powder has been processed. It is thus preferred that the polymer, after its modification, is used directly in the production of lubricant without it having previously undergone drying.

Particularly advantageously, the solutions used are taken directly from the production process of thickening agents, in particular modified natural products and processed within a few days to form a lubricant composition. The resulting fast and more homogeneous adjustment of the viscosity also enables more stable processing properties to be achieved. By using a liquid polymer, a more viscous lubricant composition can thus be achieved.

Preferably, a certain residual water content should not be exceeded in the polymer after the modification in order to achieve the improved processing properties of the polymer-water mixture. More preferably, the water content of the modified polymer after the modification should not be lowered below 5%.

In another embodiment of the invention, although the thickener can be used as a dry powder. But then, for example, it should be allowed to swell up to 24 hours in advance in order to achieve the improved processing properties of the polymer-water mixture. This also mixtures can be achieved, which after their production over a longer period, d. H. have viscosity-stable properties over several days.

The improved viscosity stability of the compositions can minimize tool wear or improve workmanship.

example 1

The production of a cooling lubricant of the ISO viscosity class 5 with the viscosity 5 mm ² / s at 40 ° C takes place by way of example:
In 97% water 1.2% alkalizing agent, z. As alkanolamine or alkali metal hydroxide with 0.7% corrosion protection acids and clear

Reaction stirred (about 1 hour). Wetting agents, solubilizers, heavy metal inhibitors are then added, and the reaction mixture is adjusted to the desired viscosity by addition of 0.6% polymer (eg Antisol FL 30).

The result is a clear, viscous solution with an average viscosity of 5.0 mm ² / s at 40 ° C and a pH of 9.0-9.3.

Example 2

The production of a cooling lubricant of the ISO viscosity class 10 with the viscosity 10 mm ² / s at 40 ° C takes place by way of example:
In 96.5% water, 1.2% alkalizing agent, z. B. alkanolamine or alkali metal hydroxide with 0.7% corrosion protection acids and stirred until clear reaction (about 1 hour). Thereafter, wetting agents, solubilizers, heavy metal inhibitors are added and the reaction mixture by adding 0.75% polymer, z. B. Antisol FL 100 adjusted to the desired viscosity.

The result is a clear, viscous solution with an average viscosity of 10.0 mm ² / s at 40 ° C and a pH of 9.0-9.3.

Example 3

The production of a cooling lubricant of the ISO viscosity class 46 with the viscosity 46 mm ² / s at 40 ° C is exemplified:
In 93% water, 2.4% alkalizing agent is mixed with 1.4% anticorrosive acids and stirred until clear reaction (about 1 hour). Thereafter, wetting agents, solubilizers, heavy metal inhibitors are added and the reaction mixture by addition of 1.45% polymer z. B. Walocel CRT 1000 adjusted to the desired viscosity.

The result is a clear, viscous solution with an average viscosity of 46.0 mm ² / s at 40 ° C and a pH of 9.0-9.3.

The novel water-based, viscous cooling lubricants according to the invention provide significantly higher performance in high-performance grinding applications compared to both conventional non-water-miscible cooling lubricants and conventional water-mixed cooling lubricants and for the first time allow to realize time-removal volumes Q'w (mm ³ / mms) of ≥ 12.

This means doubling the productivity in the production of tools solely by using the water-based lubricant according to the invention.

An example is the production of solid carbide tools z. B. by grooving; Comparative criteria are the Q'w (mm ³ / mms), the number of grooves to dressing the grinding wheel and the wear of the grinding wheel. In this case, values were obtained, which are listed in Table 3.

The novel polymeric lubricant achieves values that could previously not be achieved with conventional non-water-miscible or water-mixed cooling lubricants.

The invention is not limited to the examples described, but in many cases variable throughout the disclosure. Table 1 Tribological test system water Mineral oil (ISO viscosity class) * Liquid of the Invention (ISO Viscosity Class) ** 10 22 46 10 22 46 Brugger: surface pressure (N / mm ² ) 20.7 22.1 24.6 20.0 35.5 30.6 32.2 Reichert: Specific surface pressure (N / cm ² ) 690 723 771 748 1990 2040 2250 Shell Four-Ball Apparatus: Good Load (N) <1,000 <1,000 <1,000 <1,000 1800 1800 1800 () * ISO viscosity classification for industrial liquid lubricants acc. to DIN 51 519
() ** Inventive liquids from Chapter 2, Example 1, 2, 3 Table 2 Viscosities (mm ² / s) at 40 ° C ISO viscosity grades minimum maximum 2 1.98 2.42 3 2.88 3.52 5 4.14 5.06 7 6.12 7.48 10 9.00 11.0 15 13.5 16.5 22 19.8 24.2 32 28.8 35.2 46 41.4 50.6 Table 3 Conventional with non-water-miscible cooling lubricant Inventive polymeric cooling lubricant ISO-VG class 7 7 7.3 mm ² / s 6.2 mm ² / s Structure of the lubricant: - Base fluid about 90% mineral oil about 94% water about 0.7% polymer - Performance additives about 5% ester about 2% Schwefeladditv about 0.2% phosphorus additive - Other additives approx. 2% phosphorus additive approx. 1% anticorrosive additive defoamer approx. 3% anti-corrosive additive approx. 2% solubilizer approx. 0.1% antifoam Number of grooves 16 40 Wear (mm) 0.08 0.08 Q'w (mm ³ / mms) 3-7 15

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

• DE 102008011781 [0001]

Cited non-patent literature

• DIN 51502 [0002]
• DIN 51385 [0002]
• DIN 51502 [0002]
• DIN 51385 [0004]
• DIN 8580 [0007]
• DIN 8580 [0010]
• DIN 8589 T0 [0010]
• DIN 51385 [0012]
• Ullmanns Enzyklopädie der technischen Chemie; Römps Lexikon der Chemie and Dieter Klamann "Lubricants and Related Products", Production, Properties, Application; Verlag Chemie, Weinheim, 1982; P. 84 ff. [0034]
• ISO 3448 [0038]
• DIN 51 519 [0038]
• Guideline "OECD Guidline for testing of chemicals no. 301 " [0047]
• DIN 51 519 [0072]

Claims (20)

Single-phase, low-viscosity to high-viscosity adjusted water-based lubricant composition having an average water content of> 80 wt .-%, characterized in that the lubricant composition is mineral oil-free and contains at least one polymeric lubricant which is water-soluble in the temperature range between 10 ° C and 90 ° C. Lubricant composition according to claim 1, characterized in that the composition contains at least one corrosion inhibitor and at least one heavy metal inhibitor. Lubricant composition according to one of claims 1 or 2, characterized in that the lubricant composition contains a salt of a modified cellulose as a single polymeric lubricant. Lubricant composition according to one of the preceding claims, characterized in that it contains water-soluble polymers in the range from 0.2 to 15% by weight of the aqueous phase. Lubricant composition according to one of the preceding claims, characterized in that up to 5 wt .-% corrosion inhibiting additives are contained, in particular based on neutralized carboxylic acids having at least C8 chain length preferably with alkanolamines such as monoethanolamine, triethanolamine, diglycolamine, isobutanolamine, or hydroxides such as potassium hydroxide, Sodium hydroxide, each alone or in combination. Lubricant composition according to one of the preceding claims, characterized in that water-soluble lubricity improvers are contained up to 3 wt .-%, in particular water-soluble ester compounds and / or polymeric ethylene oxide or ethylene oxide / polypropylene oxide-based glycol compounds. Lubricant composition according to one of the preceding claims, characterized in that water-soluble high-pressure additives are up to 3 wt .-%, in particular water-soluble phosphoric acid partial esters, neutralized sulfurized fatty acids and / or esters. Lubricant composition according to one of the preceding claims, characterized in that water-soluble wear protection additives are contained up to 3 wt .-%, in particular phosphoric acid derivatives, primarily neutralized Phosphorsäurepartialesterderivate. Lubricant composition according to one of the preceding claims, characterized in that wetting agents and / or emulsifiers up to 5 wt .-% are included, in particular fatty alcohol ethoxylates with at least 5 moles of ethylene oxide and ethanol ether. Lubricant composition according to one of the preceding claims, characterized in that heavy metal inhibitors are up to 1 wt .-%, in particular those based on water-soluble triazole and / or thiadiazole derivatives, wherein the grinding of hard metal materials, the triggering of heavy metal ions is prevented. Lubricant composition according to one of the preceding claims, characterized in that additives for improving the biological stability up to 0.5 wt .-% are contained, in particular formaldehyde-releasing compounds, especially Hexahydrotriazinverbindungen, Methylbisoxazolidinverbindungen, and / or heterocycles, especially Benzisothiazolinon compounds, Sodium pyrithione and / or isothiazolone compounds. Lubricant composition according to one of the preceding claims, characterized in that defoamers up to 1 wt .-% are included, in particular modified siloxanes and / or silicic acid derivatives. Lubricant composition according to one of the preceding claims 1 to 13, characterized in that their lubricity in Brugger wear protection tests specific surface pressures ≥ 30 N / mm ² and in Reichert wear protection tests values ≥ 2000 N / cm ² . Lubricant composition according to one of the preceding claims, characterized in that its kinematic viscosity covers a range of about 2 to 1000 mm ² / s at 40 ° C. Lubricant composition according to one of the preceding claims, characterized in that the additional component is a polyhydric alcohol. A lubricant composition according to 15, characterized in that the polyhydric alcohol is selected from the groups of polyalcohols and carbohydrates, more preferably from alkanediols and alkanetriols, more preferably glycerol and the polyethers derived therefrom, as well as glucose, arabinose, ribulose, fructose and the oligo derived therefrom and / or polysaccharides and their esters and ethers. Lubricant composition according to one of Claims 1 to 16, characterized in that it is non-combustible in the range of up to 300 ° C. Use of a lubricant composition according to any one of claims 1 to 17 as a water-based cutting fluid for machining metal. Use of a lubricant composition according to any one of claims 1 to 18 as a hydraulic, gear and / or drilling fluid. Use of a lubricant composition according to any one of claims 1 to 19 as water-based, viscous cooling lubricants for the high-performance grinding of carbide tools and gears.