ES2902836T3 - Lubricating grease compositions - Google Patents

Abstract

Composition of lubricating grease, comprising a) 50 - 96% by weight of at least one fluorinated oil with a viscosity of 500 to 1500 mm2/s at 40 °C, which is selected from perfluorinated polyalkylether oils, perfluorinated silicone oils and their mixtures; b) 0.9 - 20% by weight of boron nitride and c) 3 - 25% by weight of at least one binder, the binder being organically modified bentonite or a mixture of organically modified bentonite with at least one other binder selected from alkali metal phosphates, aluminum phosphates, alkali metal silicates, alkaline earth metal silicates, aluminum silicates, alkaline earth metal carbonates, silicon dioxide, titanium dioxide, aluminum oxide and mixtures thereof, the other binder being contained in a amount of 0.1 to 50% by weight, based on the amount of organically modified bentonite.

Description

DESCRIPTION

Lubricating grease compositions

The present invention relates to lubricating grease compositions which are particularly suitable as high temperature lubricating greases and are used for lubrication in oven systems, dryers, dishwashers, electric motors or fans.

Lubricating greases generally contain a thickening medium that is dissolved or dispersed in a base oil, and dispersing media are often used for a better and more stable distribution of the thickening medium. The thickening medium is used to adjust the desired consistency, using a plurality of organic and inorganic compounds.

Mineral oils and synthetic oils are used as base oil. Perfluorinated polyalkyl ether (PFPE) is often used, i.e. synthetic fluorinated oils with good lubricating properties that are chemically non-reactive, stable at high temperatures and therefore non-toxic (see for example: "Synthetics, Mineral Oils and Bio -Based Lubricants", Leslie R. Rudnick Ed., Taylor & Francis, CRC Press, 2006). Thus, document WO 97/47710 describes compositions of lubricating greases containing as base oil a mixture of a hydrocarbon oil and a hydrocarbon oil. of perfluorinated polyalkyl ether (PFPE) and a thickening medium based on a diurea compound.The composition may also contain polytetrafluoroethylene (PTFE) and usual additives.

Document EP 657524 describes lubricating grease compositions containing a mineral oil and/or a synthetic oil with a hydrogenated base, a perfluorinated polyalkylether oil and PTFE as thickening medium.

DE 102004021 812 A1 describes a lubricating grease containing a base oil, a thickening medium, in particular a polyurea, and an inorganic material, such as silicon dioxide, distributed in the lubricating grease.

WO 2008/154997 A1 describes a lubricating grease containing a base oil, an ionic liquid, a thickening medium and an additive. The ionic liquid is intended to increase the service life and lubricating effect of the lubricant and serve to adjust the viscosity and electrical conductivity.

In the high temperature range (from 200 °C to more than 600 °C), many of the known lubricants, such as polyfluorinated compounds, reach the limits of the load-bearing capacity of the material and, therefore, despite their properties. Outstanding sliding and lubrication characteristics cannot be used in the high temperature range. Document WO 2013/037456 describes high-temperature greases containing a fluorine-free base oil, a thickening medium, which can be PTFE, additives and possibly another fluorine-free oil component.

EP 1589291 A1 discloses an oven removal guide having rolling bodies that are arranged in a cage of rolling bodies. The rolling element cage and the rolling elements have a lubricating layer which comprises a solid lubricant, for example graphite, molybdenum sulphide, tungsten disulphide or boron nitride, and which is applied and baked in the form of a lacquer.

WO 2010/046456 A1 describes a stripper guide for a baking oven, in which the raceways of the stripper guide are lubricated with boron nitride and/or a polysiloxane-containing lubricant. Document EP 648832 A1 describes lubricating grease compositions containing a fluorinated polymeric oil, boron nitride and optionally solid fluorinated polymers. Lubricating grease compositions must possess good lubricating properties even under severe operating conditions.

US 2008/0167208 describes lubricating grease compositions containing a perfluoropolyether oil with a kinematic viscosity of 50-1500 mm 2 /s at 40°C, optionally a thickening medium, as well as other customary additives. The lubricating grease compositions can be used in contact with graphite or molybdenum disulfide at high temperatures.

Lubricating greases containing PTFE form toxic vapors at high temperatures and are also washed out relatively quickly with water during cleaning processes. On the other hand, PTFE-free lubricating greases have the drawback that they are washed out with water even more quickly than PTFE-containing lubricating greases. Therefore, the present invention aims to provide lubricating grease compositions with improved water washability. Furthermore, the lubricating grease compositions should exhibit improved thermal stability and produce longer lubrication life at high temperatures.

This object is achieved by a lubricating grease composition comprising at least one high viscosity fluorinated oil, hexagonal boron nitride and a binding medium.

Therefore, the present invention relates to a lubricating grease composition comprising:

(a) 50 - 96% by weight of at least one fluorinated oil with a viscosity of 500 to 1500 mm ² /s, preferably 500 to 1100 mm ² /s, at 40 °C, which is selected from perfluorinated polyalkylether oils , perfluorinated silicone oils and their mixtures;

(b) 0.9 - 20% by weight of boron nitride and

(c) 3-25% by weight of at least one binding medium, the binding medium being organically modified bentonite or a mixture of organically modified bentonite with at least one other binding medium selected from among alkali metal phosphates, aluminum phosphates, silicates alkali metals, alkaline earth metal silicates, aluminum silicates, alkaline earth metal carbonates, silicon dioxide, titanium dioxide, aluminum oxide and mixtures thereof, the other binding medium being contained in an amount of 0.1 to 50% in weight, referred to the amount of organically modified bentonite.

The kinematic viscosity is measured with the Anton Paar SVM 300 viscometer at a temperature of 40 °C.

Component (a) is selected from perfluorinated polyalkylether oils or perfluorinated silicone oils and mixtures thereof.

Suitable perfluorinated polyalkyl ether oils are described, for example, in WO 97/47710 or EP 657 524.

According to one embodiment, the perfluorinated polyalkylether oils correspond to the formula:

A ¹ -[OCF ² ] ^a -[OC ² F ⁴ ] ^b -[OC ³ F ⁶ ] ^c -[OC ⁴ F ^e ] ^d -[OCF ² CF(CF ³ )] ^e -[OCF(CF ³ ) CF ² ] ^f - A ²

where

A ¹ is -CF ³ , -C ² F ⁵ or -C ³ F ⁷ ;

A ² is -OCF ³ , -OC ² F ⁵ or -OC ³ F ⁷ ;

a, b, c, d, e and f are statistically distributed and are 0 or an integer from 1 to 200, although they cannot all be 0 at the same time.

According to another embodiment, e/a and f/a are in the range from 20 to 50 and b/a in the range from 0.5 to 2.

According to another embodiment, c and d are 0. Preferably the perfluorinated polyalkylether is composed of the following units:

-[OCF ² CF(CF ³ )] ^e or

-[OCF ² ] ^a -[OC ² F ⁴ ] ^b o

-[OCF ² ] ^to -[OCF ² CF(CF ³ )] ^e

where e/a is in the range 20 to 50 and b/a is in the range 0.5 to 2.

According to another embodiment, the perfluorinated polyalkyl ether oils correspond to the formula:

CF ³ -[OCF(CF ³ )CF ² ] ^f -[OCF ² ] ^a -[OCF ² CF(CF ³ )] ^e - OCF3

where a, e, and f are statistically distributed and are either 0 or an integer from 1 to 200, although they cannot all be 0 at the same time, and e/a and f/a are in the range 20 to 50.

According to another embodiment, the perfluorinated polyalkyl ether oils correspond to the formula:

TO-[AB] ^z -[A-B'] ^z' -AT' (I)

where:

- A = -(X) ^a -O-A'-(X') ^b -A' representing a perfluoropolyether chain, comprising one or more repeating units selected from (CF ² O), (CF ² CF ² O ), (CF ² CF ² CF ² O) and (CF ² CF ² CF ² CF ² O) and possibly units (CF(CF ³ )O), (CF(CF ³ )CF ² O), (CF ² CF (CF ³ )O);

X and X' are the same or different from each other and represent -CF ² -, -CF ² CF ² - or optionally -CF(CF ³ )-;

a and b are equal to or different from each other and are integers with a value of 0 or 1, with the proviso that in the case of block A attached to the final group TO-, the index a is 1 and in the case of block A attached to the final group T', the index b is -B is a block of units derived from one or more olefins of formula (la), of which at least one is homopolymerizable by free radicals

-[(CR ¹ R ² -CR ³ R ⁴ MCR ⁵ R ⁶ - CR7R8)j']- (Ia)

where

j is an integer from 1 to 5,

j' is an integer from 0 to 4, provided that (j+j') is greater than 2 and less than 5;

R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are the same or different from each other and are chosen from halogen; H; perhaloC ¹ -C ⁶ alkyl, where the halogen is F and/or Cl; C ¹ -C ⁶ alkyl optionally containing heteroatoms; and C ¹ -C ⁶ oxyperfluoroalkyl;

z is an integer greater than or equal to 2;

z' is 0 or an integer;

wherein z and z' have a value such that the number average molecular weight of the polymer of formula (I) is in the range of 500-500,000;

B' is a block derived from one or more olefins of formula (Ia), but where at least one of the substituents R ¹ to R ⁸ is different than in block B, where (j j') is greater than or equal to 2 and less than 5;

the end groups T and T' are the same or different from each other and are perfluoroalkyl groups with 1 to 3 carbon atoms, a fluorine atom being able to be replaced by a chlorine or hydrogen atom; or non-fluorinated C ¹ -C ⁶ alkyl groups.

These polyether oils are described in EP 2089 443.

In one embodiment, component (a) may additionally comprise a non-fluorinated oil, in particular a mineral oil. The non-fluorinated oil is generally contained in an amount of 0.1 to 40% by weight, in particular 0.5 to 30% by weight, based on the amount of fluorinated oil.

The lubricating grease composition further comprises boron nitride, in particular hexagonal boron nitride. In one embodiment, the lubricating grease composition comprises hexagonal boron nitride. According to another embodiment, the boron nitride has a BET surface area in the range of 10 to 20 m ² /g, determined according to ISO 9277:2010. According to another embodiment, the boron nitride has a mean particle size D50 of 1 to 10 pm, in particular 2 to 6 pm, determined by laser diffractometry (Malvern Mastersizer 3000). A suitable boron nitride is available, for example, under the trade name ^Boronid® from ESK Ceramics GmbH & Co. KG, Germany.

The lubricating grease composition further comprises a binder. The binder generally has a mean particle size D50 in the range of 1 to 10 pm, preferably 2 to 8 pm, as determined by laser diffractometry.

According to the invention, the binding medium is organically modified bentonite or a mixture of organically modified bentonite with at least one other binding medium which is selected from alkali metal phosphates, aluminum phosphates, alkali metal silicates, alkaline earth metal silicates, aluminum silicates , alkaline earth metal carbonates, silicon dioxide, titanium dioxide, aluminum oxide and mixtures thereof. The additional binder is contained in an amount of 0.1 to 50% by weight, in particular 0.5 to 40% by weight, based on the amount of organically modified bentonite.

Organically modified fumed silica is preferable as silicon dioxide, and organically modified fumed titanium dioxide is preferable as titanium dioxide. Modified fumed silica and modified fumed titanium dioxide are products that have been surface-treated with an organosilane, in particular an alkylsilane. Corresponding products, such as Aerosil R 912, Aerosil 812, Aerosil 805, Aerosil R 202, Aeroxide ^® TiO ² T 805, Aeroxide ^® TiO ² NKT 90, VP NKT 65 are commercially available, for example from Evonik Industries AG, Germany, or Wacker Chemie AG, Germany.

Bentonite is a mixture of different clay minerals with the most important component being montmorillonite (60% to 80%). Other minerals that accompany it are quartz, mica, feldspar, pyrite or calcite. The term "bentonite" includes all naturally occurring versions as well as modified bentonites. Bentonite is commercially available in the form of different commercial products. In the context of the present invention, organically modified, in particular hydrophobically modified, bentonite is used, for example the commercial product BARAGEL(R) from Elementis Specialties Inc., USA.

The hydrophobically organically modified bentonite can be obtained, for example, by reacting natural or purified bentonite with quaternary ammonium compounds in the sense of an exchange reaction. cationic, in which for example the alkaline cations are exchanged for quaternary ammonium compounds. Quaternary ammonium compounds suitable for this reaction are, for example, those of the general formula R1R2R3R4N+ X-, where X is an equivalent of an anion, for example sulfate, hydrogen sulfate, alkyl sulfate, aryl sulfate, alkyl sulfonate, aryl sulfonate, halide, phosphate, carbonate, alkyl phosphate, alkyl carbonate, nitrate, alkoxide, hydroxide, tetrafluoroborate or perchlorate, especially halide, and R1, R2, R3 or R4 may be the same or different and may be C1- ^{C20 alkyl} . For example, R 1 and R 2 may be the same or different, they are C ¹ -C ⁴ alkyl, and R ³ and R ⁴ , the same or different, are C ¹² -C ²⁰ alkyl. In particular, quaternary ammonium salts can be used in which X is halide, in particular chloride, R1 and R2 methyl and ^R3 and ^R4 , the same or different, are ^C16 - ^C18 alkyl. The BARAGEL© commercial product is bentonite, modified with Me ² N(C ¹⁶ -C ¹⁸ alkyl) ² Cl.

If bentonite is used as the binding medium, in a preferred embodiment the lubricating grease composition additionally comprises water in an amount of 0.01 to 1% by weight, in particular 0.05 to 0.2% by weight with reference to the total mass of the composition. The water acts in this case as an activating agent for the bentonite, in particular to activate the dispersing and thickening properties of the bentonite.

According to another embodiment, the lubricating grease composition according to the invention may contain at least one additive, in particular an additive that is customary in the field of lubricating grease compositions. Preferably the additive is selected from antioxidants, for example functionalized perfluoropolyalkyl ether, as described in EP 1 354 932 A1 and US 5,550,277; wear protection additives, for example functionalized perfluoropolyalkylether, as described for example in WO 2016/020232; corrosion protection means, for example sodium sebacate, functionalized perfluoropolyalkylether, as described in US 5,550,277; dyes, eg azo dyes and solid lubricants, eg molybdenum disulphide, tungsten disulphide, tin sulphide.

In one embodiment, the lubricating grease composition is essentially free of PTFE.

libre de líquido iónico. In another embodiment, the lubricating grease composition is essentially

free ionic liquid.

libre de grafito. In another embodiment, the lubricating grease composition is essentially

graphite free.

"Essentially free" means that the lubricating grease composition contains less than 0.5% by weight of PTFE, less than 0.5% by weight of ionic liquid or less than 0.5% by weight of graphite, in particular in each case 0% by weight of these components, with reference to the total mass of the composition.

The manufacture of the lubricating grease composition according to the invention generally occurs by mixing the components under high shear force, for example using a rotor-stator mixer, followed eventually by homogenization, for example using a roller mill.

Surprisingly, it has been shown that the lubricating grease compositions according to the invention have a number of advantageous properties compared to known lubricating greases:

- very good compatibility of all components,

- better adhesion to metal surfaces

- longer service life at high operating temperature,

- lower washability with water; this results in the possibility of repeated machine cleaning of lubricated metal parts, for example pull-out rails of cooking ovens in dishwashers, without impairing the function of the metal parts

- no formation of possibly toxic decomposition products when heated above 100 °C

- better properties at high temperatures

- additional lubricating effect due to the oil component compared to products in powder form.

The lubricating grease compositions according to the invention are suitable for lubrication in the temperature range from -30°C to 700°C, in particular from 20 to 300°C. Therefore, they can be used in many areas. They can be used for the lubrication of sliding guides and roller wheels in furnace systems or roller and slide bearings in dryers, electric motors or fans, for the lubrication of tools, especially tools for plastic injection molding, machines and installations , especially for the food and feed industry. Examples of applications are the lubrication of: roller and sliding bearings, sliding guides, valves, joints, slides, column guides, ejectors and other sliding surfaces, such as in circular conveyor installations, painting lines, calenders, ovens, fans, switches, stretch film installations, extraction installations, textile machines, wood pressing systems, pumps, dryers, motors, tire moulds, construction machines, electrical engineering and the automobile industry, elastomer and plastic engineering , as well as applications in the corrugated cardboard industry, paper industry and steel industry and machines and installations, for example in the food and feed industry.

The lubricating grease composition according to the invention is preferably used for the lubrication of sliding guides and rollers in furnace systems or roller and sliding bearings in dryers, electric motors or fans. The use of the lubricating grease compositions according to the invention for the lubrication of kiln draw rails is especially preferred.

The use of the lubricating grease composition is carried out by applying it to the parts to be lubricated in an amount suitable for lubrication. The lubricating grease composition according to the invention is preferably applied in the form of a paste. This form of application allows a very precise selection and coating of the application surfaces. The lubricating grease composition can be applied in a simple manner without the lubricating grease composition being able to flow or drip, for example at the ends of the paths of the oven extraction rails.

An optional post-treatment after application of the lubricating grease composition by vibratory finishing allows for better distribution and adhesion of the lubricating grease eg on a metal substrate.

The lubricating grease composition is preferably thixotropic, ie the viscosity is reduced by mechanical influence and the original viscosity is restored again after the shearing stress has ended. As a result, the pastes can be spread relatively easily over the surface of, for example, oven draw rails under pressure load without dripping.

The following examples explain the invention without limiting it.

Example 1:

Two perfluorinated polyether oils (68% by weight of PFPE 1 oil, 500 cSt at 40 °C from DuPont, USA and 10% by weight of PFPE 2 oil, 1005 cSt at 40 °C) were placed in a mixing vessel. C from DuPont, USA) and heated at 100 °C for 15 min with stirring. BARAGEL® (14.9% by weight, hydrophobically organically modified bentonite from Elementis Specialties Inc., USA) was then added to the mixing vessel, heating was turned off, and the resulting mixture was stirred for five minutes. minutes. 0.1% by weight of water was then added and the mixture was stirred for 30 minutes. After cooling to room temperature, boron nitride (5% by weight Boronid®, ESK Ceramics GmbH & Co. KG, Germany) and a corrosion protection medium (2% by weight, Irgacor ®, BASF SE, Germany) and the resulting mixture was stirred for 30 minutes. The resulting lubricating grease was homogenized with a roller mill. The % by weight data refer in each case to the total weight of the lubricating grease.

Test program and results

The lubricating grease composition made according to example 1 was first subjected to a VKA test (four-ball apparatus, ASTM D1831/DIN 51350-4). A VKA welding load of 4800 N and a VKA wear of 0.9 mm at 150 kg/1 min of load were determined.

The thermal stability at 300 °C was also determined for the lubricating grease composition manufactured according to Example 1. The evaporation rate over time was used as a measure of thermal stability:

Hours: 0 24 72 140

Evaporation rate [%]: 0 14 26 41

In addition, it was determined for the composition of lubricating grease manufactured according to example 1:

- corrosion of steel (Emcor) in distilled water (ISO 11007): grade 1/1

- the viscosity of the base oil at 40 °C (DIN 51562): 575 mm2/s and

- NLGI consistency class (DIN 51818): NLGI 1

Washability tests

Washability tests were carried out for the lubricating grease composition made according to Example 1 and three comparative samples (Comparative Example 1, Comparative Example 2, Comparative Example 3). To do this, the different samples were applied on oven extraction rails and were subjected to the following cycle. The oven draw rails were exposed to a temperature of 250°C in an oven for 4 hours; the rails were then removed from the oven and treated with a commercially available dishwashing detergent in a dishwasher at 70°C for 2 hours; After the wash cycle, the rails were removed from the dishwasher and dried at 105°C for 1 hour. (3 cycles were done for each sample, so the rails were in the oven for a total of 12 hours and in the dishwasher for 6 hours). Composition of the comparative examples (% by weight referred to the total weight of the composition):

Comparative example 1:

74.75% PFPE (perfluorinated polyether; 500 mm2/s)

5% PTFE (polytetrafluoroethylene)

0.25% average corrosion protection

Comparative example 2:

81% PFPE (500mm2/s)

10% PFPE (1005mm2/s)

% PTFE

2% SiO2

2% average corrosion protection

Comparative example 3:

10% PFPE (1005mm2/s)

83% PFPE (500mm2/s)

5% boron nitride

1% graphite

1% WS ² (tungsten sulphide)

The following results were obtained:

Example 1: weight loss after the third wash: < 50%; the rail can be easily moved. Comparative example 1: weight loss after the third wash: 75%

Comparative example 2: weight loss after the third wash: 50%

Comparative example 3: weight loss after the third wash: 60%

Comparative Example 2 containing PTFE develops toxic vaporous decomposition products and is therefore not suitable for use in baking ovens, despite good washing results.

Resistance tests

Endurance tests were carried out for the lubricating grease composition made according to Example 1 and two comparative samples (Comparative Examples 4 and 5). To do this, the different samples were placed on oven extraction rails and the extraction rails were mounted on side racks. The grids were then installed in a baking oven. A test load was positioned in the center of a tray in the oven. The loaded tray was inserted and extracted using a pneumatic cylinder. The rails were subjected to an endurance test with 24,000 cycles. After every 6,000 cycles, the moving force and descent of the rails were tested, and the rails were likewise subjected to a dishwasher after every 6,000 cycles. After a total of 24,000 cycles, the rails were disassembled and examined. The test was performed with the following parameters and according to the following schematic process

Composition of the comparative examples (% by weight with reference to the total weight of the composition):

Comparative Example 4: For Comparative Example 2, see above.

Comparative example 5:

90.5% PFPE (500mm2/s)

6% Boron Nitride

3.25% SiO2

0.25% corrosion protection medium

The following results were obtained:

Example 1: The sample passed the test (5 washes, good rolling properties up to 18,000 cycles, continuing up to 24,000 cycles, slightly worse rolling properties).

Example The sample passed the test (5 washes, good rolling properties up to 18,000 cycles, comparative 4: continuing up to 24,000 rolling properties worse). However, the composition develops toxic decomposition products at temperatures above 250°C.

Example Sample failed test (failed after 12000 cycles, balls stuck due to comparative 5: lack of grease).

Claims (16)

1. Composition of lubricating grease, comprising a) 50 - 96% by weight of at least one fluorinated oil with a viscosity of 500 to 1500 mm2/s at 40 °C, which is selected from perfluorinated polyalkylether oils, perfluorinated silicone oils and their mixtures; b) 0.9 - 20% by weight of boron nitride and c) 3-25% by weight of at least one binder, the binder being organically modified bentonite or a mixture of organically modified bentonite with at least one other binder selected from among alkali metal phosphates, aluminum phosphates, alkali metal silicates, alkaline earth metal silicates, aluminum silicates, alkaline earth metal carbonates, silicon dioxide, titanium dioxide, aluminum oxide and mixtures thereof, the other binder being present in an amount of 0.1 to 50% by weight, based on the amount of organically modified bentonite. 2. Lubricating grease composition according to claim 1, in which the fluorinated oil has a viscosity of 500 to 1100 mm2/s at 40°C. 3. Lubricating grease composition according to one of the preceding claims, in which the fluorinated oil is selected from perfluorinated polyalkylether oils and mixtures thereof. Lubricating grease composition according to one of the preceding claims, in which the boron nitride is hexagonal boron nitride, in particular hexagonal boron nitride. 5. Lubricating grease composition according to one of the preceding claims, containing less than 0.5% by weight of polytetrafluoroethylene based on the total mass of the composition. Lubricating grease composition according to one of the preceding claims, containing less than 0.5% by weight of an ionic liquid, based on the total mass of the composition. Lubricating grease composition according to one of the preceding claims, containing less than 0.5% by weight of graphite, based on the total mass of the composition. 8. Lubricating grease composition according to one of the preceding claims, further comprising at least one non-fluorinated oil. 9. Lubricating grease composition according to one of the preceding claims, additionally comprising 0.01 to 1% by weight of water, based on the total weight of the composition. 10. Lubricating grease composition according to one of the preceding claims, further comprising at least one additive that is preferably selected from antioxidants, means for improving the viscosity index, means for lowering the pour point, wear protection additives, means of protection against corrosion, means of protection against rust, dyes and solid lubricants. 11. Lubricating grease composition according to claim 10, comprising 0.05-5% by weight of at least one additive. Use of a lubricating grease composition according to one of Claims 1 to 11 for lubrication in the temperature range from -30°C to 700°C, in particular from 100°C to 310°C. 13. Use of a lubricating grease composition according to one of claims 1 to 11 for the lubrication of sliding guides and rolling wheels in furnace systems or roller and sliding bearings in dryers, electric motors or fans, for the lubrication of tools, in particular tools for plastic injection moulding, machines and installations, in particular for the food and feed industry. 14. Lubrication method in which a lubricating grease composition according to one of claims 1 to 11 is applied to the parts to be lubricated. Lubrication method according to claim 14, in which the lubricating grease composition is applied in the temperature range from -30°C to 700°C, in particular from 100°C to 310°C. 16. Lubrication method according to claim 14 or 15 for the lubrication of sliding guides and rolling wheels in furnace systems or roller and sliding bearings in dryers, electric motors or fans, for the lubrication of tools, in particular tools for plastic injection molding, machines and installations, in particular for the food and feed industry.