JP5759685B2 - Lubricating oil composition - Google Patents

Description

  The present invention relates to a lubricating oil composition.

As a carbon material, ones derived from petroleum resources are still used today. However, the problem of resource depletion is becoming a reality, and new carbon materials different from those derived from petroleum resources are being demanded. One of these is the movement to use natural plant-derived oils and fats as essential oils.
For example, vegetable oils and fats represented by soybean oil, tung oil, palm oil and the like can be obtained by obtaining a crude oil by squeezing, extracting or the like of a plant and purifying it by distillation or the like. These vegetable fats and oils are triglycerides of saturated or unsaturated fatty acids, and are used in various fields such as cooking, fuel, medicine, and lubricating oil. In addition, an attempt to obtain a lubricating base oil having excellent low-temperature fluidity, oxidation stability, and lubricity by the transesterification method using the above-described vegetable oil as a raw material has been disclosed (see Patent Document 1).

In addition, plant-derived essential oil contains alcohol, aldehyde, ketone, ester, phenol, hydrocarbon, and the like as components. Hydrocarbons include terpenes and sesquiterpenes. As terpenes, allocymene, oscene, myrcene, dihydromyrcene and the like are known as chain terpenes, and α-pinene, β-pinene, limonene, camphene, α-ferrandrene, terpinene, terpinolene, 3-carene as cyclic terpenes. Etc. are known. Terpenes are often used in fragrances, etc., but are hydrocarbons having the molecular formula of C ₁₀ H ₁₆ and have high hydrolysis stability and volume resistivity, but have low viscosity, flash point, etc. Not suitable for. On the other hand, as sesquiterpenes, chain sesquiterpenes such as farnesene are known, and as cyclic sesquiterpenes, cedrene, β-caryophyllene, kazinene, valencene, tyuopsen, guaien and the like are known. These are hydrocarbons having a molecular formula of C ₁₅ H ₂₄ , have high hydrolytic stability and high volume resistivity, and have moderate viscosity and flash point, so that they can be used as a low viscosity lubricant base material. .

JP-A-10-53780

  Since the vegetable oils and fats described above are esters, they are susceptible to hydrolysis and are also polar substances, so they have a low volume resistivity and cannot be used in fields that require insulation. Furthermore, many vegetable oils and fats have unsaturated fatty acids and have low oxidation stability. Furthermore, although vegetable oils and fats have a high viscosity index, their pour points are as high as -5 ° C to room temperature, so they cannot be used in low temperature environments. Even if this point uses the transesterification method like patent document 1, a situation does not change. In addition, sesquiterpenes as plant-derived essential oils have a problem of low oxidative stability because they have unsaturated bonds even if they are hydrocarbons.

  An object of the present invention is to provide a lubricating oil composition having a low pour point, a high viscosity index, high oxidation stability, high hydrolysis resistance, and high volume resistivity.

  The present inventors have long hydrophorene (a kind of cyclic sesquiterpene hydrocarbon) contained in essential oils obtained from cypress, pine, etc., which has high hydrolysis stability and high volume resistivity, and further has appropriate viscosity and flash point. Therefore, it was found that it can be used as a low viscosity lubricant base material. Furthermore, since the olefin part of longifolene has a terminal olefin structure having a bulky substituent, the oxidation stability is also high. The present invention has been completed based on these findings.

That is, the present invention provides the following lubricating oil composition.
(1) A lubricating oil composition comprising longifolene , wherein the longifolene is obtained by refining at least one of pine essential oil and cypress essential oil , -A lubricating oil composition comprising caryophyllene, wherein the content of β-caryophyllene is 5% by mass or less, and the amount of the longifolene is 60% by mass or more based on the total amount of the composition .
(2) In the lubricating oil composition according to (1) above, the longifolene is (1S, 3aR, 4S, 8aS) -4,8,8-trimethyl-9-methylene-decahydro-1,4-methano. A lubricating oil composition characterized by being azulene (3) In the lubricating oil composition according to the above (1) or (2), at least one of mineral oil and synthetic oil is used as a base oil A lubricating oil composition.
(4) In the lubricating oil composition according to the above (3), the synthetic oil is a low molecular weight polybutene, a low molecular weight polypropylene, an α-olefin oligomer having 8 to 14 carbon atoms or a hydride thereof, a polyol ester, A lubricating oil composition comprising at least one of a dibasic acid ester, an aromatic polycarboxylic acid ester, a phosphoric acid ester, an alkylbenzene, an alkylnaphthalene, a silicone oil, and a fluorine-based oil.
(5) In the lubricating oil composition according to any one of (1) to (4) above,
A lubricating oil comprising at least one of an antioxidant, an oily agent, an extreme pressure agent, a cleaning dispersant, a viscosity index improver, a rust inhibitor, a metal deactivator and an antifoaming agent. Composition.
(6) In the lubricating oil composition according to any one of (1) to (5) above, the composition may be an internal combustion engine, a fluid coupling, a slide bearing, a rolling bearing, an oil-impregnated bearing, a fluid bearing, Compressor, chain, gear, hydraulic, watch parts, hard disk, refrigerator, cutting, rolling, drawing, rolling, forging, heat treatment, heat medium, coolant, coolant, cleaning, shock absorber, rust prevention, brake, and A lubricating oil composition characterized by being used in any of sealing devices.

  Since the lubricating oil composition of the present invention comprises longifolene, it has a low pour point, a high viscosity index, high oxidation stability, high hydrolysis resistance and high volume resistivity.

2 is a GC chart of sample oil in Example 1. FIG. 4 is a GC chart of sample oil in Example 2.

  The lubricating oil composition of the present invention is characterized by containing longifolene. That is, the present invention is a lubricating oil containing longifolene. Here, longifolene is (1S, 3aR, 4S, 8aS) -4,8,8-trimethyl-9-methylene-decahydro-1,4-methanoazulene, specifically a compound having the following structure It is.

Longifolene is contained in essential oils of pine and cypress, and high purity Longifolene can be easily obtained by refining. Longifolene after refining can be used as a lubricating oil as it is, but can also be used as a base oil for lubricating oil. When longifolene is used as a base oil, a lubricating oil composition having a low pour point, a high viscosity index, high oxidation stability, high hydrolysis resistance and high volume resistivity can be obtained. Moreover, since longifolene itself has an appropriate viscosity, it is excellent in lubricity.
The lubricating oil composition of the present invention may contain a base oil other than the above longifolene. However, in order to exert the effect as the lubricating oil composition of the present invention, the amount of Longifolene in the composition is preferably 60% by mass or more, more preferably 70% by mass or more, and 80% by mass. More preferably, it is even more preferably 90% by mass or more.

Other base oils can be appropriately selected from, for example, mineral oil and synthetic oil.
Examples of mineral oils include distillate oils obtained by atmospheric distillation of paraffinic crude oil, intermediate crude oil or naphthenic crude oil, or by distilling atmospheric distillation residue oil under reduced pressure. Examples include refined oils obtained by refining, specifically solvent refined oils, hydrogenated refined oils, dewaxed oils, and clay-treated oils.
Synthetic oils include, for example, low molecular weight polybutene, low molecular weight polypropylene, α-olefin oligomers having 8 to 14 carbon atoms and hydrides thereof, polyol esters (for example, trimethylolpropane fatty acid ester, pentaerythritol Fatty acid esters), dibasic acid esters, aromatic polycarboxylic acid esters (for example, trimellitic acid esters, pyromellitic acid esters, etc.), ester compounds such as phosphoric acid esters, alkylaromatic compounds such as alkylbenzene and alkylnaphthalene, Examples thereof include silicone oil and fluorine-based oil (for example, fluorocarbon, perfluoropolyether, etc.).
These base oils can be used singly or in combination of two or more.

  On the other hand, longifolene obtained from essential oils of pine and cypress contains β-caryophyllene as an impurity. β-caryophyllene is (1R, 4E, 9S) -4,11,11-trimethyl-8-methylene-bicyclo [72.0] undec-4-ene, which is a compound having the following structure: .

  If β-caryophyllene is present in the lubricating oil composition, it may inhibit oxidation stability and may also adversely affect the viscosity index. Therefore, the content of β-caryophyllene is preferably 5% by mass or less, more preferably 3% by mass or less, based on the total amount of the composition.

  The lubricating oil composition of the present invention can be used for various applications by blending predetermined additives. Examples of the additive include an antioxidant, an oily agent, an extreme pressure agent, a cleaning dispersant, a viscosity index improver, a rust inhibitor, a metal deactivator, and an antifoaming agent. These can be used individually by 1 type or in combination of 2 or more types.

  As the antioxidant, amine-based antioxidants, phenol-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants that are used in conventional hydrocarbon-based lubricating oils can be used. These antioxidants can be used singly or in combination of two or more. Examples of the amine antioxidant include monoalkyl diphenylamine compounds such as monooctyl diphenylamine and monononyl diphenylamine, 4,4′-dibutyldiphenylamine, 4,4′-dipentyldiphenylamine, 4,4′-dihexyldiphenylamine, 4 , 4′-diheptyldiphenylamine, 4,4′-dioctyldiphenylamine, dialkyldiphenylamine compounds such as 4,4′-dinonyldiphenylamine, polyalkyl such as tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldiphenylamine, tetranonyldiphenylamine Diphenylamine compounds, α-naphthylamine, phenyl-α-naphthylamine, butylphenyl-α-naphthylamine, pentylphenyl α- naphthylamine, hexylphenyl -α- naphthylamine, heptylphenyl -α- naphthylamine, octylphenyl -α- naphthylamine, and naphthylamine-based compounds such as nonylphenyl -α- naphthylamine.

Examples of the phenolic antioxidant include monophenolic compounds such as 2,6-di-tert-butyl-4-methylphenol and 2,6-di-tert-butyl-4-ethylphenol, 4,4 ′ Examples include diphenolic compounds such as -methylenebis (2,6-di-tert-butylphenol) and 2,2'-methylenebis (4-ethyl-6-tert-butylphenol).
Examples of the sulfur-based antioxidant include 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol, phosphorus pentasulfide and Examples thereof include thioterpene compounds such as a reaction product with pinene, and dialkylthiodipropionates such as dilauryl thiodipropionate and distearyl thiodipropionate.
Examples of phosphorus antioxidants include triphenyl phosphite, diethyl [3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] phosphonate, and the like.
The blending amount of these antioxidants is usually 0.01% by mass or more and 10% by mass or less, preferably 0.03% by mass or more and 5% by mass or less, based on the total amount of the composition.

  Examples of the oily agent include fatty alcohols, fatty acid compounds such as fatty acids and fatty acid metal salts, ester compounds such as polyol esters, sorbitan esters, and glycerides, and amine compounds such as aliphatic amines. The blending amount of these oil-based agents is usually 0.1% by mass or more and 30% by mass or less, and preferably 0.5% by mass or more and 10% by mass or less based on the total amount of the lubricating oil from the viewpoint of the blending effect.

Examples of the extreme pressure agent include a sulfur-based extreme pressure agent, a phosphorus-based extreme pressure agent, an extreme pressure agent containing sulfur and a metal, and an extreme pressure agent containing phosphorus and a metal. These extreme pressure agents can be used singly or in combination of two or more. Any extreme pressure agent may be used as long as it contains at least one of a sulfur atom and a phosphorus atom in the molecule and can exhibit load resistance and wear resistance. Examples of extreme pressure agents containing sulfur in the molecule include sulfurized fats and oils, sulfurized fatty acids, sulfurized esters, sulfurized olefins, dihydrocarbyl polysulfides, thiadiazole compounds, alkylthiocarbamoyl compounds, triazine compounds, thioterpene compounds, dialkylthiodipropionate compounds, etc. Can be mentioned.
As extreme pressure agents containing sulfur, phosphorus and metals, zinc dialkylthiocarbamate (Zn-DTC), molybdenum dialkylthiocarbamate (Mo-DTC), lead dialkylthiocarbamate, tin dialkylthiocarbamate, dialkyldithiophosphate Examples include zinc (Zn-DTP), molybdenum dialkyldithiophosphate (Mo-DTP), sodium sulfonate, calcium sulfonate, and the like. Typical examples of extreme pressure agents containing phosphorus in the molecule are phosphate esters such as tricresyl phosphate and amine salts thereof. The blending amount of these extreme pressure agents is usually 0.01% by mass or more and 30% by mass or less, more preferably 0.01% by mass or more and 10% by mass or more based on the total amount of the composition from the viewpoint of blending effect and economy. It is as follows.

Examples of the cleaning dispersant include metal sulfonate, metal salicylate, metal finate, and succinimide. The blending amount of these detergent dispersants is usually 0.1% by mass or more and 30% by mass or less, and preferably 0.5% by mass or more and 10% by mass or less based on the total amount of the composition from the viewpoint of the blending effect.
As the viscosity index improver, for example, polymethacrylate, dispersed polymethacrylate, olefin copolymer (for example, ethylene-propylene copolymer), dispersed olefin copolymer, styrene copolymer (for example, Styrene-diene hydrogenated copolymer, etc.). The blending amount of these viscosity index improvers is usually 0.5% by mass or more and 35% by mass or less, and preferably 1% by mass or more and 15% by mass or less based on the total amount of the composition from the viewpoint of the blending effect.

Examples of the rust inhibitor include metal sulfonates, succinic acid esters, alkylamines and alkanolamines such as monoisopropanolamine. The blending amount of these rust preventives is usually 0.01% by mass or more and 10% by mass or less, and preferably 0.05% by mass or more and 5% by mass or less based on the total amount of the composition from the viewpoint of the blending effect.
Examples of the metal deactivator include benzotriazole and thiadiazole. The preferred compounding amount of these metal deactivators is usually 0.01% by mass or more and 10% by mass or less, preferably 0.01% by mass or more and 1% by mass or less, based on the total amount of the composition from the viewpoint of blending effect. It is.
Examples of the antifoaming agent include methyl silicone oil, fluorosilicone oil, and polyacrylate. The blending amount of these antifoaming agents is usually 0.0005% by mass or more and 0.01% by mass or less based on the total amount of the composition from the viewpoint of the blending effect.

  The lubricating oil composition of the present invention includes an internal combustion engine, a fluid coupling, a slide bearing, a rolling bearing, an oil bearing, a fluid bearing, a compression device, a chain, a gear, a hydraulic pressure, a timepiece component, a hard disk, a refrigerator, cutting, rolling, and drawing. It can be used for various applications such as rolling, forging, heat treatment, heat medium, coolant, coolant, cleaning, shock absorber, rust prevention, brake, and sealing device.

  EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by these examples. Specifically, as shown below, each sample oil was prepared and subjected to various evaluations.

[Example 1]
80% pure Longifolene (manufactured by Honghe Fine Chemical Co., Ltd.) was precision distilled through a 40 mmφ, 120 cm column packed with packing material, and (1S, 3aR, 4S, 8aS) -4,8,8-trimethyl having a purity of 90% by mass. -9-methylenedecahydro-1,4-methanoazulene (boiling point 145-149 ° C./30 mmHg fraction) was obtained in a yield of 70%. This fraction was used as sample oil. This fraction contained 2.9% by mass of β-caryophyllene. For reference, the measurement result by GC (gas chromatograph) is shown in FIG.

[Example 2]
Longifolene (manufactured by Yasuhara Chemical Co., Ltd.) having a purity of 60% by mass was used as the sample oil. This contained 14.4% by mass of β-caryophyllene. For reference, the measurement result by GC is shown in FIG.

[Comparative Example 1]
Vegetable oil (commercial soybean oil) was used as sample oil.

[Method for measuring properties of sample oil]
Various properties of each sample oil described above were measured by the following methods. The results are shown in Table 1.
(1) Kinematic viscosity Kinematic viscosity at 40 ° C and 100 ° C was measured according to JIS K 2283.
(2) Viscosity index It was measured according to JIS K 2283.
(3) Density at 15 ° C. Measured according to JIS K 2249.
(4) Pour point Measured according to JISK 2269.
(5) Volume resistivity It measured based on JISC2101.
(6) RBOT life 0.5 mass% of 2,6-di-tert-butyl-4-methylphenol was added to each sample oil described above. For these sample oils, the time (minutes) to reach the end point of the pressure drop was measured according to JISK 2514.

〔Evaluation results〕
It turns out that the sample oil of an Example has a low pour point compared with the sample oil (soybean oil) of a comparative example, and its low-temperature fluidity | liquidity is favorable. Moreover, since the sample oil of an Example is a hydrocarbon compound and is not an ester compound like a comparative example, it can be understood that hydrolysis resistance is also good.
It can be understood that the sample oil of Example 1 having a low β-caryophyllene content has a long RBOT remaining time, good oxidation stability, and a long life when used as a lubricating oil. Moreover, since the sample oil of Example 1 with a low β-caryophyllene content has a high volume resistivity, it is suitable for applications that require insulation. Furthermore, since the sample oil of Example 1 having a low β-caryophyllene content has a high viscosity index, it can be understood that the change in viscosity due to temperature is small and suitable as a lubricating oil. And it can be understood that the sample oil of Example 1 having a low β-caryophyllene content has very good oxidation stability and has a very long life as a lubricating oil.

Claims (6)

A lubricating oil composition comprising longifolene,
The longifolene is obtained by refining at least one of pine essential oil and hinoki essential oil,
The composition contains β-caryophyllene, and the content of β-caryophyllene is 5% by mass or less,
A lubricating oil composition, wherein the amount of the longifolene is 60% by mass or more based on the total amount of the composition . The lubricating oil composition according to claim 1, wherein
A lubricating oil composition wherein the longifolene is (1S, 3aR, 4S, 8aS) -4,8,8-trimethyl-9-methylene-decahydro-1,4-methanoazulene The lubricating oil composition according to claim 1 or 2,
A lubricating oil composition comprising a mineral oil or a synthetic oil as a base oil. In the lubricating oil composition according to claim 3,
The synthetic oil is low molecular weight polybutene, low molecular weight polypropylene, an α-olefin oligomer having 8 to 14 carbon atoms or a hydride thereof, polyol ester, dibasic acid ester, aromatic polycarboxylic acid ester, phosphoric acid ester, alkylbenzene. A lubricating oil composition characterized by being at least one of alkyl naphthalene, silicone oil, and fluorine-based oil. In the lubricating oil composition according to any one of claims 1 to 4,
A lubricating oil comprising at least one of an antioxidant, an oily agent, an extreme pressure agent, a cleaning dispersant, a viscosity index improver, a rust inhibitor, a metal deactivator and an antifoaming agent. Composition. In the lubricating oil composition according to any one of claims 1 to 5,
The composition is an internal combustion engine, fluid coupling, slide bearing, rolling bearing, oil-impregnated bearing, fluid bearing, compression device, chain, gear, hydraulic, watch part, hard disk, refrigerator, cutting, rolling, drawing, drawing, rolling, A lubricating oil composition characterized by being used in any of forging, heat treatment, heat medium, coolant, coolant, cleaning, shock absorber, rust prevention, brake, and sealing device.

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