DE102009031342A1 - Use of a lubricating oil comprising a microencapsulated lubricant additive, as engine oil, which is useful in internal combustion engine, or as gear oil, where a lubricant additive concentration is maintained in lubricating oil - Google Patents

Abstract

Use of a lubricating oil comprising at least one microencapsulated lubricant additive (2), as engine oil or gear oil, where a lubricant additive concentration is maintained in the lubricating oil, and the lubricant additive is released from microcapsules by at least one release mechanism comprising: (a) destruction of the microcapsules by shear; (b) thermal destruction of the microcapsules; or (c) release of the lubricant additive from the microcapsules by diffusion, is claimed. Independent claims are also included for: (1) use of at least one microencapsulated lubricant additive in a lubricating oil for a motor vehicle with an internal combustion engine, where the lubricant additive of the microcapsule is released by a release mechanism (a, b, c) during the operation of the motor vehicle, and the lubricant additive concentration in the lubricating oil is maintained to readily reduce the friction, abrasion, corrosion, oxidation, surface tension or the viscosity and/or to readily increase the flock- and/or stock temperature of the lubricating oil; and (2) an internal combustion engine with an engine oil, where the engine oil comprises the microencapsulated lubricant additive.

Description

The The invention relates to a use of lubricating oils with microencapsulated lubricant additives and use of microencapsulated lubricant additives in lubricating oils for motor vehicles with internal combustion engine. Furthermore, the invention relates to an internal combustion engine with microencapsulated Lubricating oil containing lubricant additives.

From the WO 2007/024590 A1 For example, there is known a method of lubricating a mechanical device that includes a release system for additives for the controlled release of the additives from an additive gel in a functional fluid to both better store and handle the functional fluids and to improve the post-dosing of the additives.

The DE 10 2005 061 195 A1 discloses a variable heat capacity coolant for internal combustion engines that includes a phase change material that may be microencapsulated that allows for improved thermal management of internal combustion engines.

In the DE 10 2006 058 224 A1 A method of reducing a coefficient of friction by providing an amount of an oil-soluble nanospherical component derived from a photocurable poly (2-cinnamoyloxyalkyl acrylate) core and a diblock acrylate copolymer corona in a lubricant composition is described. Thus, the coefficient of friction of the lubricant composition is significantly improved, so that the wear can be reduced when using lubricant compositions with relatively low viscosity.

outgoing From this prior art, it is desirable to use refined lubricating oil with lubricant additives, a refresh of the gradually depleted of additives lubricating oil provides without an additional dispensing system for Post-dosing of fresh additive is required and the subsequent dosing thus automatically during operation. Further should the total amount of additive needed be reduced, which also reduces the amount of ashing products formed can be, so that the lubricating oil quality over can be kept constant for a longer period, and thus an emission and consumption reduction of the lubricating oil or an extension of the oil change intervals can be achieved.

These Task is on the one hand by using a lubricating oil with microencapsulated lubricant additives with the characteristics of Claim 1 and by the use of microencapsulated lubricant additives in a lubricating oil for a motor vehicle with an internal combustion engine solved with the features of claim 12.

The Task of creating an internal combustion engine with an engine oil, which contains microencapsulated lubricants, is replaced by the Internal combustion engine with the features of claim 19 solved.

further developments the respective inventions are in the subclaims executed.

A first embodiment of the invention relates to the Use of a lubricating oil containing an engine oil or may be a transmission oil, and one or more lubricant additives contains contained in microcapsules. A lubricant additive concentration, respectively a required content of lubricant additive in the oil, the one for optimum oil quality is required while doing while running obtained by the lubricant additives by different Release mechanisms are released from the microcapsules can, whereby this release automatically during operation. The in the production of the lubricating oil allow added micro-encapsulated lubricant additives over automatic replenishment by the release mechanisms a reduction of the total additive amount, and consequently also the ashing products resulting from the additives.

The Release mechanisms enable a targeted release the lubricant additives, each by reaching a corresponding load value during operation of the engine or transmission the additive either by thermal or mechanical destruction the microcapsules, as a result of the heating of the oil or by occurring shear forces, or by diffusion of the Lubricant additive released by the microcapsule walls becomes.

While the operation of the engine and transmission is continuously additive consumed, so that on the one hand incineration products can arise, on the other hand changed the fluidity of the lubricating oil becomes. As a result, the viscosity increases and as a result more shear forces occur in the oil circuit, as soon as a temperature increase in the lubricating oil by the increased Friction occurs. The oil temperature, which is the thermal Release mechanism influences, thus directing the aging state of the lubricating oil, as well as the shear forces influencing viscosity, also due to oil aging increases.

In another embodiment, they may be necessary to destroy the microcapsule walls Shearing forces may also be provided by an emergency run of the transmission or the engine.

Around now to set the place and / or the time at which the different Release mechanisms take place, on the one hand, a condition the microcapsules are changed, which affect the Take release mechanisms, such as a microcapsule wall thickness, a microcapsule wall density, material of the microcapsule wall and size and shape of the microcapsules. The additive properties affecting the diffusion through the microcapsule wall are the molecular size and polarity of the lubricant additive and a concentration gradient between the inside of the microcapsule and the surrounding lubricating oil. The aforementioned features of microcapsules, such as wall thickness, wall density and wall material, also affect the rate of diffusion.

A another embodiment of the invention refers to the use of microencapsulated lubricant additives in a lubricating oil for a motor vehicle having an internal combustion engine, the microencapsulated lubricant additives being antioxidants, High-pressure additives, wear protection additives, friction reducers and / or an organic pH stabilizer. The lubricant additive is removed from the microcapsule during vehicle operation the lubricating oil by one of the above-mentioned release mechanisms released, leaving the lubricant additive concentration in the lubricating oil is maintained, which is responsible for a reduction of friction, Wear, corrosion, oxidation, surface tension and viscosity and an increase in flocculation and / or temperature of the lubricating oil.

After all an embodiment relates to an internal combustion engine, with an engine oil containing microencapsulated lubricant additives, is lubricated. The in an oil circuit of the internal combustion engine occurring shear forces, temperatures and / or lubricant additive concentrations in the engine oil thereby release the lubricant additives from the microcapsules, the lubricant additives being antioxidants, High pressure / wear additives, friction reducers and / or organic pH stabilizers include. The microencapsulated lubricant additive itself can be present in liquid form as a lubricating fluid, However, it may also be dissolved in an oil lubricant additive or lubricant additive dispersed in an oil.

Of the organic pH stabilizer can preferably be an organic, residue-free be a combustible base.

The Material of the microcapsule wall may consist of a polymer which oil insoluble and stable up to a temperature of at least 130 ° C. Preferably, such a microcapsule wall material may be a melamine resin be.

One substantial proportion of one or more of the lubricant additives is in microencapsulated form in the lubricating oil, so that a reduced amount of additive for one over one longer lasting oil quality can be provided without replenishment, as the "replenishment" automatically by the release of the additives from the microcapsules during operation. The efficiency of the additives can be on this Way be increased. Likewise, this can extend the oil change intervals be achieved.

The Microcapsules are in a weight concentration of 0.5 to 10%, based on the total weight of the capsules, in the lubricating oil.

A mean particle size of the microcapsules may be at 100 nm to 10 microns, preferably have the microcapsules a mean particle size of 0.5 microns up to 5 μm. The lubricant additive-containing microcapsules can in particular a round or spherical Have shape.

The Lubricating oil containing the lubricant additive-containing microcapsules may include an engine oil for an internal combustion engine or a transmission oil, wherein the lubricating oil a Base oil selected from one of Groups 1 to 5 is and a mineral oil, a synthetic or a semi-synthetic oil can be.

These and further advantages are provided by the following description further clarified with reference to the accompanying figures. Of the Reference to the figures in the description is to facilitate Understanding of the subject. Objects or Parts of objects that are essentially the same or similar may be provided with the same reference numerals. The figures are merely a schematic representation of an embodiment the invention.

there demonstrate:

1 perspective view of the crankshaft and piston of an engine with schematically shown release of fresh additive,

2a -D schematically different release mechanisms.

The inventive use of a lubricating oil containing microencapsulated lubricant additives and the use of microencapsule Lubricating additives in a lubricating oil for an internal combustion engine engine refer to microencapsulated lubricant additives contained in a lubricating oil, which may be an engine oil or a transmission oil.

Typical lubricant additives used in microencapsulated form in the invention and which are normally used at an additive concentration of 1 to 99% by weight in a suitable solvent such as a hydrocarbon oil, e.g. Dissolved and / or dispersed, include viscosity improvers, friction modifiers, detergents, cloud point improvers, pour point improvers, demulsifiers (separation aids), flow improvers, antistatic agents, dispersants such as polyalkylene succinimide dispersants (described in U.S. Pat US-A-5,851,965 . 5,853,434 and 5,729,729 ), Antioxidants, foam suppressants, corrosion / rust inhibitors, high pressure / antiwear agents, sealer swelling agents, lubricating aids, antifoggants and mixtures thereof. Several of these components are known to those skilled in the art and are used in conventional amounts with the additives and compositions described herein.

Antioxidants or oxidation inhibitors prolong the quality of the lubricating oil by suppressing the formation of oxidation products such as sludge and paint-like deposits and thus an increase in the viscosity. Common antioxidants include generally hindered phenols, sulfurized hindered phenols, alkaline earth metal salts of alkylphenol thioesters with C5-C12 alkyl side chains, sulfurized alkylphenols, metal salts of sulfurized or unsulfurized alkylphenols, e.g. Calcium nonylphenol sulfide, ashless oil-soluble phenates and sulfurized phenates, phosphosulfurized or sulfurized hydrocarbons, phosphoric esters, metal thiocarbamates and oil-soluble copper compounds as in US-A-4,867,890 as well as hindered phenols and diarylamines, alkylated phenothiazines, sulfurized compounds and ashless dialkyldithiocarbamates.

anti oxidations may be alkyl-substituted phenols such as 2,6-di-tert-butyl-4-methylphenol, or Phenate sulfides, phosphosulfurized terpenes, sulfurized esters, aromatic Amines, diphenylamines, alkylated diphenylamines and hindered phenols, bis-nonylated Diphenylamine, nonyl-diphenylamine, octyl-diphenylamine, bis-octylated Diphenylamine, bis-decylated diphenylamine, decyl-diphenylamine as well Mixtures thereof.

exemplary hindered phenols include, but are not limited to 2,6-di-tert-butylphenol, 4-methyl-2,6-di-tert-butylphenol, 4-ethyl-2,6-di-tert-butylphenol, 4-propyl-2,6-di-tert-butylphenol, 4-butyl-2,6-di-tert-butylphenol, 4-pentyl-2-6-di-tert-butylphenol, 4-hexyl-2,6-di-tert-butylphenol, 4-heptyl-2,6-di-tert-butylphenol, 4- (2-ethylhexyl) -2,6-di-tert-butylphenol, 4-octyl-2,6-di-tert-butylphenol, 4-nonyl-2,6-di-tert-butylphenol, 4-decyl-2,6-di-tert-butylphenol, 4-undecyl-2,6-di-tert-butylphenol, 4-dodecyl-2,6-di-tert-butylphenol, 4-tridecyl-2,6-di-tert-butylphenol, 4-tetradecyl-2,6-di-tert-butylphenol.

Methylene bridged hindered phenols include, but are not limited to, 4,4-methylene-bis (6-tert-butyl-o-cresol), 4,4-methylene-bis (2-tert-amyl) o-cresol), 2,2-methylenebis (4-methyl-6-tert-butylphenol), 4,4-methylenebis (2,6-di-tert-butylphenol) and mixtures thereof, as in of the US Publication 2004/0266630 described.

usual EP (high pressure) / wear reducers include sulfur or Chlorosulfur EP additives, an EP additive based on a chlorinated hydrocarbon or a phosphorus-EP additive or mixtures thereof. examples for such EP additives are amine salts of phosphoric acid, chlorinated wax, organic sulfides and polysulfides, such as benzyl disulfide, bis (chlorobenzyl) disulfide, Dibutyl tetrasulfide, sulfurized walrat oil, sulfurized Methyl esters of oleic acid sulphurised alkylphenol, sulfurized dipentene, sulfurized terpene, and sulfurized Diels-Alder adducts; Phosphosulfurierte hydrocarbons, such as the reaction product of phosphorus sulphide with turpentine or methyloleate, phosphorus esters, such as the dihydrocarbon and trihydrocarbon phosphate, d. h., dibutyl phosphate, Diheptyl phosphate, dicyclohexyl phosphate, pentylphenyl phosphate; Dipentylphenyl phosphate, tridecyl phosphate, distearyl phosphate and Polypropylene substituted phenol phosphate, metal thiocarbamates, such as zinc dioctyldithiocarbamate and barium heptylphenol diazide, such as zinc dicyclohexyl phosphorodithioate and the zinc salts of a phosphorodithio-acid combination; also mixtures thereof can be used.

Wear additives / extreme pressure additives For example, an amine salt of a phosphoric ester acid, dialkyl dithiophosphoric acid ester and salts thereof; Phosphites and phosphorus-containing carboxyl esters, Ethers and amides and mixtures thereof.

A common friction modifier may be a phosphate ester or a salt, but also a phosphite, for example an ester or salt of a monohydrocabyl, dihydrocarbyl or a trihydrocarbyl phosphate, or the corresponding phosphite, where each hydrocarbyl group is saturated. Each hydrocarbyl group contains between 8 and 30 carbon atoms. Further, hydrocarbyl groups may be alkyl groups. Examples of hydrocarbyl groups include tridecyl, tetradecyl, pen tadecyl, hexadecyl, heptadecyl, octadecyl groups and mixtures thereof.

Farther For example, a friction modifier may be a fatty imidazoline, the fatty substituent containing about 8 to 30 carbon atoms. The substituent can unsaturated, but is preferably saturated. A fatty imidazoline can be obtained by reaction of a fatty carboxylic acid be prepared with a polyalkylenepolyamine.

In the DE 10 2006 058 224 A1 discloses the use of a sulfur- and phosphorus-free organomolybdenum compound as an additional friction modifier by reacting a sulfur and phosphorus-free molybdenum source (e.g., molybdenum trioxide, ammonium molybdate, sodium molybdate and potassium molybdate) with an amino (e.g., monoamines, diamines or polyamines) and / or alcohol groups (for example monosubstituted alcohols, diols or bis-alcohols or polyalcohols) containing organic compound can be prepared. The preparation of sulfur- and phosphorus-free organomolybdenum groups can be carried out by reacting certain basic nitrogen compounds with a molybdenum source, as in US-A-4,259,195 and 4,261,843 described; Alternatively, sulfur- and phosphorus-free organomolybdenum groups can be prepared by reacting a hydrocarbyl-substituted hydroxyalkylated amine with a molybdenum source, as in US Pat US-A-4,164,473 described.

Another possibility is to react a phenol-aldehyde condensation product, a monoalkylated alkylenediamine and a molybdenum source, as in US-A-4,266,945 described. Finally, sulfur and phosphorus-free organomolybdenum groups include compounds made by reacting a fatty oil, diethanolamine, and a molybdenum source, as in US Pat US-A-4,889,647 and compounds prepared by reacting a fatty oil or a fatty acid with 2- (2-aminoethyl) aminoethanol and a molybdenum source, as described in U.S. Patent Nos. 5,496,074; US-A-5,137,647 described. Further, by reacting a secondary amine with a molybdenum source, such compounds can be prepared as in US-A-4,692,256 described. Reacting a diol, a diamino or aminoalcohol compound with a molybdenum source, as in US-A-5,412,130 and reacting a fatty oil, a monoalkylated alkylenediamine and a Mo-lybdänquelle, as in US-A-6,509,303 and reacting a fatty acid, a monoalkylated alkylenediamine and glycerides with a molybdenum source, as described in U.S. Pat US-A-6,528,463 also enables the preparation of a sulfur and phosphorus-free organomolybdenum-containing compound.

usual Rust inhibitors may be selected from a group comprising nonionic Polyoxyalkylenepolyols and their esters, polyoxyalkylenphenols and anionic Alkyl sulfonic acids are selected.

A demulsifier may be used in a small amount which does not exceed 0.1% by weight of the active ingredient and is preferably 0.001 to 0.05% by weight. In the EP 0 333 522 there is described a preferred demulsifier formed by reacting an alkylene oxide with an adduct of a bis-epoxide and a polyhydric alcohol.

Pour point improvers are well known and are used to improve fluidity of the lubricating oil at low temperatures by sinking the stick temperature used. Typical pour point additives include C8-C18 dialkyl fumarate / vinyl acetate copolymers, polyalkyl methacrylates and the same.

When Foam damper is a variety of compounds in question for example, of the polysiloxane type, such as silicone oil or polydimethylsiloxane.

The advantageous maintenance of the lubricant concentration in the lubricating oil according to the invention takes place by means of various release mechanisms, which in 2a . 2 B . 2c and 2d are clarified.

In 2a indicate the two block arrows a in the oil circuit existing shear forces, so that from the present in the lubricating oil microcapsules 1 lubricant additive 2 is released as on the right side of 2a you can see. This happens as soon as the shear forces in the oil circuit increase due to an increase in viscosity, so that fresh additive is only "replenished" if necessary, so that a lower additive concentration than in the prior art (up to 30% by weight of additives in the lubricating oil) can be achieved, which also decreases the amount of ashing products, which in turn increases the oil change intervals in which the lubricating oil has optimal properties.

2 B represents a runflat condition of engine or transmission which also releases lubricant additive 2 from the microcapsules 1 causes. During an emergency state, the bearing operation is maintained even at deficient lubrication at least for a while The encapsulation of the additives thus also allows a combination of incompatible additives, it can be encapsulated in a microcapsule high-pressure / wear protection additives, which provide improved protection of motor vehicle bearings. Other capsules may include antioxidants that are the ge reduce the total amount of additive required for a motor vehicle. In a commercial vehicle, the antioxidant microcapsules may prolong oil change intervals.

Overall, the use of microcapsules with lubricant additives enables a reduction in emissions and fuel consumption of the internal combustion engines in that the improved oil quality enables a smoother running of the moving engine or transmission parts. The thermal release mechanism is in 2c represented by the increased heat supply is indicated by the serpentine arrows b. The thermal release takes place when the oil temperature rises due to increased friction as a result of the depletion of additive, so that here at specific points of increased oil temperature or at the time of increased oil temperature additive is released.

2d shows on the right side the release of the lubricant additive 2 by diffusion from the capsule interior 4 through the capsule wall 3 in the lubricating oil 5 ,

The Diffusion is due both to the nature of the microcapsules, namely the wall thickness, the wall density or the Wall material, as well as by properties of the lubricant additive itself, such as its molecular size and polarity. The Diffusion rate is also determined by the Lubricant concentration gradient determined between the inside of the microcapsule and the surrounding lubricating oil is present, so that the diffusion occurs amplified when the lubricating oil is depleted of additive. The release mechanisms the destruction by shear forces respectively of thermal destruction are determined by the microcapsule wall thickness, density and material determined. Furthermore, this plays the size and shape of the microcapsules matter. The mean particle size the microcapsules can be between 100 nm and 10 μm, but preferably between 0.5 .mu.m and 5 .mu.m. The microcapsules are preferably round.

The lubricating oil, which is made from a base oil by adding the microencapsulated lubricant additives, also serves to lubricate an internal combustion engine, its crankshaft 10 and pistons 11 in 1 are shown. The release of the lubricant additive 2 from the microcapsules takes place directly to places that are exposed to increased loads.

Of the Total content of in the production of lubricating oil in The base oil added microcapsules may be added 0.5 to 10 wt .-%, based on the total weight of the capsule, are.

The Base oil can be a mineral oil, a synthetic one or semi-synthetic oil, and from groups 1 to 5, which are known in the art, wherein Group 1 has a composition of less than 90% saturated Hydrocarbons with a sulfur content of more than 0,03% m and a viscosity index of 80 to 120. group 2 denotes oils with more than 90% saturated Hydrocarbons having a sulfur content of less than 0.03% m and a Viscosity index from 80 to 120 while group 3 a composition corresponding to a group 2 and sulfur content contains but a viscosity index of over 120 having. Group 4 designates polyalphaolefins and group 5 all other base oil components, for example esters.

The oil-insoluble Microcapsule wall material is preferably up to a temperature stable from about 130 ° C, allowing thermal release by Decomposition of the microcapsule wall providing polymer when exceeded this 130 ° C takes place. Such a polymer may be Be melamine resin.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - WO 2007/024590 A1 [0002]
• - DE 102005061195 A1 [0003]
• - DE 102006058224 A1 [0004, 0036]
• US 5851965 A [0027]
• US 5853434 [0027]
• US 5729729 [0027]
• - US 4867890 A [0028]
• US 2004/0266630 [0031]
• US Pat. No. 4,259,195 A [0036]
• - US 4261843 [0036]
• - US 4164473 A [0036]
• US 4266945A [0037]
• - US 4889647 A [0037]
• - US 5137647 A [0037]
• US 4692256 A [0037]
• - US 5412130 A [0037]
• - US 6509303 A [0037]
• - US 6528463 A [0037]
• EP 0333522 [0039]

Claims (25)

Use of a lubricating oil containing at least one microencapsulated lubricant additive, wherein the lubricating oil is an engine oil or a transmission oil, characterized in that a lubricant additive concentration in the lubricating oil is maintained by adding the lubricant additive from the microcapsules ( 1 by at least one release mechanism from the group comprising: destruction of the microcapsules ( 1 ) by shearing (a), - thermal destruction (b) of the microcapsules ( 1 ), - release of the lubricant additive by diffusion (c) from the microcapsules ( 1 ) is released. Use according to claim 1, characterized in that an emergency run of the transmission or of the engine shears the destruction of the microcapsules ( 1 ). Use according to claim 1 or 2, characterized in that a place and / or a time for the execution of the release mechanism - by a predetermined nature of the microcapsules ( 1 ) which is at least one microcapsule wall thickness, a microcapsule wall density, a microcapsule wall material and / or a size of the microcapsules, and / or predetermined by a predetermined property of the lubricant additive comprising a lubricant additive molecular size, a lubricant additive polarity, a lubricant additive concentration gradient. Use according to at least one of the claims 1 to 3, characterized in that the lubricant additive at least an antioxidant, a high pressure additive, a wear protection additive, a friction reducer, and / or an organic pH stabilizer, in particular an organic base. Use according to at least one of the claims 1 to 4, characterized in that the lubricant additive a Lubricating fluid, a lubricant additive dissolved in an oil or lubricant additive dispersed in an oil. Use according to claim 4 or 5, characterized that the organic pH stabilizer is an organic, residue-free is combustible base. Use according to at least one of the claims 3 to 6, characterized in that the microcapsule wall material an oil-insoluble, up to a temperature of at least 130 ° C stable polymer, in particular a melamine resin is. Use according to at least one of claims 1 to 7, characterized in that the microcapsules ( 1 ) in the lubricating oil a weight fraction of 3 to 10 wt .-%, based on the total weight of the microcapsules ( 1 ), exhibit. Use according to at least one of claims 1 to 8, characterized in that the microcapsules ( 1 ) have an average particle size in the range of 100 nm to 10 .mu.m, in particular in the range of 0.5 .mu.m to 5 .mu.m Use according to at least one of claims 1 to 9, characterized in that the microcapsules ( 1 ) are spherical. Use according to at least one of the claims 1 to 10, characterized in that the lubricating oil a Base oil comprising the base oil groups 1 to 5 is selected and that is a mineral oil, a synthetic or semi-synthetic oil or a mixture the above. Use of at least one microencapsulated lubricant additive in a lubricating oil for a motor vehicle with internal combustion engine, characterized in that the microencapsulated lubricant additive is selected from a group comprising an antioxidant, a high pressure additive, a wear protection additive, a friction reducer, and / or an organic pH Stabilizer, in particular an organic base, and that the lubricant additive from the microcapsule ( 1 ) is released during operation of the motor vehicle by a release mechanism (a, b, c), wherein a lubricant additive concentration in the lubricating oil is maintained to reduce friction, wear, corrosion, oxidation, surface tension, or viscosity , and / or to provide an increase in flock and / or stick temperature of the lubricating oil. Use according to claim 12, characterized that the lubricant additive is a lubricating fluid, an in an oil dissolved lubricant additive or in an oil dispersed lubricant additive. Use according to claim 12 or 13, characterized that the organic pH stabilizer is an organic, residue-free is combustible base. Use according to at least one of claims 12 to 14, characterized in that a microcapsule wall material is an oil-insoluble, up to a temperature of at least 130 ° C stable polymer, in particular a melamine resin. Use according to at least one of claims 12 to 15, characterized in that the microcapsules ( 1 ) in the lubricating oil, a weight fraction of 0.5 to 10 wt .-%, based on the total weight of the microcapsules ( 1 ), exhibit. Use according to at least one of claims 12 to 16, characterized in that the microcapsules ( 1 ) have an average particle size in the range of 100 nm to 10 .mu.m, in particular in the range of 0.5 .mu.m to 5 .mu.m. Use according to at least one of claims 12 to 17, characterized in that the microcapsules ( 1 ) are spherical. Internal combustion engine with an engine oil, characterized in that the engine oil contains microencapsulated lubricant additives, which by at least one release mechanism from the group comprising: - Destruction of the microcapsules ( 1 ) by shearing (a), - thermal destruction (b) of the microcapsules ( 1 ), - release of the lubricant additive by diffusion (c) from the microcapsules ( 1 ), are releasable. Internal combustion engine according to claim 19, characterized that the lubricant additive is a lubricating fluid, an in an oil dissolved lubricant additive or in an oil dispersed lubricant additive. Internal combustion engine according to claim 19 or 20, characterized characterized in that the organic pH stabilizer is an organic, Residue-free combustible base is. Internal combustion engine according to at least one of the claims 19 to 21, characterized in that a microcapsule wall material an oil-insoluble, up to a temperature of at least 130 ° C stable polymer, in particular a melamine resin is. Internal combustion engine according to at least one of claims 19 to 22, characterized in that the microcapsules ( 1 ) in the lubricating oil in the range of 0.5 to 10 wt .-%, based on the total weight of the microcapsules ( 1 ), exhibit. Internal combustion engine according to at least one of claims 19 to 23, characterized in that the microcapsules ( 1 ) have an average particle size in the range of 100 nm to 10 .mu.m, in particular in the range of 0.5 .mu.m to 5 .mu.m Internal combustion engine according to at least one of claims 19 to 24, characterized in that the microcapsules ( 1 ) are spherical.

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