JPH08209160A - Lubricant composition - Google Patents

Abstract

PURPOSE: To obtain a lubricant compsn. which has fundamental characteristics, such as lubricity, hydrolysis resistance, heat resistance, and low-temp. flowability, in a good balance and is low in cost and practicable. CONSTITUTION: This compsn. comprises 95-20wt.% synthetic hydrocarbon lubricant comprising an α-olefin oligomer (PAO) and an ethylene-α-olefin cooligomer and 5-80wt.% ester. The ester is selected from among an ester (b1) obtd. by reacting castor oil with a fatty acid or a condensed fatty acid, an ester (b2) obtd. by reacting a castor oil fatty acid with a fatty acid or a condensed fatty acid, an ester (b3) obtd. by reacting the ester b1 or the ester b2 with an alcohol, and an ester (b4) obtd. by at least partly replacing castor oil or castor oil fatty acid of the ester b1, ester b2 or ester b3 with a hydrogenated castor oil or a hydrogenated castor oil fatty acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a practical lubricating composition having a well-balanced basic required characteristics such as lubricity, hydrolysis resistance, heat resistance, and low temperature fluidity, and in particular, lubricating oil for automobiles. , A lubricating oil suitable for aircraft lubricating oil, marine lubricating oil, industrial lubricating oil, grease base oil or plastic working oil.

[0002]

2. Description of the Related Art Conventionally, mineral oils, which are paraffinic or naphtheneic hydrocarbons, have been mainly used as lubricating oils, but recently, various synthetic lubricating oils have been widely used in order to cope with severe operating conditions. It is being adopted.

Typical synthetic lubricating oils are (1) hydrocarbon type such as α-olefin oligomer (PAO) and polybutene, (2) ester type such as diester, hindered (polyol) ester and phosphoric acid ester, (3) ether type such as polyalkylene glycol, polyphenyl ether, alkyl polyphenyl ether, etc., (4) silicone type,
(5) Halocarbon type, etc. (See, for example, pages 33 to 34 of "Lubrication Economy, May 1989", pages 49 to 55 of "Lubrication Economy, April 1991").

Among these synthetic lubricating oils, those suitable for use as automotive lubricating oils, aircraft lubricating oils, marine lubricating oils, industrial lubricating oils, grease base oils, and plastic working oils are α-olefins. It is said to be a mixture of an oligomer or polybutene with a synthetic ester such as a dibasic acid ester or a hindered alcohol ester.

The present invention relates to rolling oil (which does not require low temperature fluidity), which is not the object of the present invention.
JP-A-50-146556 discloses that 1 mol of castor oil or its alkylene oxide adduct, and 4 to 4 carbon atoms.
Rolling oil for steel sheet is shown which has as its main component an esterification of 0.5 to 3 mol of 24 fatty acids. There is also a description that this esterified product can be used as a mixture with animal and vegetable oils and fats and mineral oils. The fatty acids having 4 to 24 carbon atoms mentioned here include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid,
Linolenic acid, maleic acid, adipic acid, azelaic acid,
It is sebacin. In the examples, 1 mol of castor oil and 3 stearic acid are referred to as an esterification product of castor oil.
1 mol of castor oil (Example 1), 3 mol of castor oil and 3 mol of oleic acid (Example 2), 1 mol of castor oil and less than 3 mol of myristic acid (Example 3) I have been given.

The present invention also relates to a rolling oil (which does not require low-temperature fluidity) which is not the object of the present invention. In JP-A-56-14591, a reaction between a castor oil-based compound and a polyfunctional compound is described. A metal rolling oil for rolling under high pressure using the compound obtained by the above is shown, and its example is obtained by further reacting 1 mol of sebacic acid with a reaction product of 1 mol of castor oil and 1 mol of stearic acid. Polyester (Example 1), a polyester obtained by further reacting 1 mol of azelaic acid with a reaction product of 1 mol of castor oil and 2 mol of stearic acid, 1 mol of castor oil and 2 mol of stearic acid. A reaction product with 0.5 mol of dimer acid (Example 3) and the like are mentioned.

[0007]

Among the lubricating oils having low temperature fluidity, conventionally used mineral oils and synthetic lubricating oils have the following problems. That is, although mineral oil has an advantage of being inexpensive, it has a drawback that heat resistance and oxidation resistance are insufficient. Hydrocarbon-based synthetic lubricating oils are less susceptible to chemical reactions, but have the problems of relatively high friction coefficient, insufficient load resistance and oiliness, and insufficient lubricity. Ester-based synthetic lubricating oils have good lubricity, but have a problem of poor hydrolysis resistance. Many ether-based synthetic lubricating oils are expensive, lack compatibility with mineral oil, and are water-absorbing, and thus easily generate rust.
Silicone-based and halocarbon-based synthetic lubricating oils have extremely high baking limit loads, but are extremely expensive, and therefore have severe restrictions on their use.

Lubricants in which a synthetic ester such as a dibasic acid ester or a hindered alcohol ester is mixed with an α-olefin oligomer or polybutene are currently used as an automobile lubricating oil, an aircraft lubricating oil, a marine lubricating oil, an industrial lubricant. It can be said that it is relatively preferable for use as a lubricating oil, grease base oil, and plastic working oil, but it is not yet satisfactory in terms of lubricity, heat resistance, and hydrolysis resistance. , There is room for further improvement.

Since the rolling oil for steel plates disclosed in JP-A-50-146556 is literally intended as a rolling oil for steel plates, low temperature fluidity is not taken into consideration, and the rolling oil is used as it is for the above-mentioned lubrication. Even when trying to convert it to oil (automobile lubricating oil, aircraft lubricating oil, marine lubricating oil, industrial lubricating oil, grease base oil, plastic working oil), it is often not suitable for these applications. Furthermore, even if the esterified product of the invention of the same publication is mixed with the animal and vegetable oils and fats or mineral oils referred to in the publication, it gives unsatisfactory results in terms of oxidative stability etc. to the above-mentioned applications such as automobile lubricating oils. .

The metal rolling oil for high-pressure rolling described in JP-A-56-14591 is also not intended for low-temperature fluidity because it is also intended for rolling oil, and the compounds described in the publication are not considered. Even if it is intended to be used for the above-mentioned automobile lubricating oils and the like, since it is reacted with a bifunctional fatty acid, the hydrolysis resistance is remarkably inferior, resulting in a very unsatisfactory result.

Against this background, the present invention has well-balanced basic required properties such as lubricity, hydrolysis resistance, heat resistance and low temperature fluidity, and is a cost-effective and practical lubricant. Composition, especially automotive lubricating oil,
An object of the present invention is to provide a lubricating composition suitable for an aircraft lubricating oil, a marine lubricating oil, an industrial lubricating oil, a grease base oil or a plastic working oil.

[0012]

The lubricating composition of the present invention is a synthetic hydrocarbon lubricant comprising an α-olefin oligomer or an ethylene-α-olefin cooligomer.
(A), an ester of castor oil and a fatty acid or condensed fatty acid (b1), an ester of castor oil fatty acid and a fatty acid or condensed fatty acid (b2), these esters (b1), (b2) further reacted with alcohol Ester (b3) and the above-mentioned esters (b1), (b2), and (b3) at least part of castor oil or castor oil fatty acid is replaced with hydrogenated castor oil or hydrogenated castor oil fatty acid b4) in a weight ratio of at least one ester (B) selected from the group consisting of 9
It is composed of a composition of 5: 5 to 20:80.

The present invention will be described in detail below.

As the synthetic hydrocarbon type lubricant (A), α-
Olefin oligomers or ethylene-α-olefin cooligomers or mixtures thereof are used. The former α-olefin oligomer is generally called PAO, and is produced, for example, by polymerizing ethylene to obtain a polymer in the oligomer region (for example, about 8 to 30 carbon atoms). The latter ethylene-α-olefin cooligomer is commercially available, for example, from Mitsui Petrochemical Co., Ltd. under the trade name of "Lucant".

As the ester (B), at least one compound selected from the following groups is preferably used. Castor oil is less than 3 in the molecule (more accurately
It is a triglyceride containing 2.7) ricinoleic acid (that is, castor oil fatty acid) as a constituent fatty acid, and ricinoleic acid (that is, castor oil fatty acid) has a double bond between the 9th and 10th carbon atoms among 18 carbon atoms. And a fatty acid having an OH group at the 12th carbon atom.

Ester of castor oil and fatty acid or condensed fatty acid (b1), ester of castor oil fatty acid and fatty acid or condensed fatty acid (b2), further reaction of these esters (b1) and (b2) with alcohol Ester (b3), ・ Ester of the above-mentioned ester (b1), (b2), (b3) having a structure in which a part of castor oil or castor oil fatty acid is replaced with hydrogenated castor oil or hydrogenated castor oil fatty acid (b4).

As the fatty acid in (b1), caprylic acid, capric acid, octylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, montanic acid, oleic acid, ricinoleic acid (castor oil fatty acid), 1
Fatty acids having 8 or more carbon atoms such as 2-hydroxystearic acid (hydrogenated castor oil fatty acid) (especially iodine value 1
The fatty acid may be 10 or less, and may have a branched structure like isostearic acid. In addition, fatty acids derived from natural products containing these fatty acids may be used.

Examples of the condensed fatty acids in (b1) include condensed fatty acids obtained by reacting castor oil fatty acids with each other or with castor oil fatty acids and other fatty acids having no OH group. The degree of condensation is appropriately about dimer to hexamer.

In addition, if the amount is a nominal amount that does not impair the gist of the present invention, a fatty acid having a carbon number of 7 or less, a divalent fatty acid, or a high degree of unsaturation (iodine number) together with the above fatty acid or condensed fatty acid. (Higher) fatty acid can also be used in combination.

The number of constituent fatty acid units per 1 mol of castor oil in the ester in (b1) is from 1 to 10 mol, in particular
It is preferably 1.5 to 7 mol. When the ratio of the constituent fatty acid units is too small, the compatibility with the synthetic hydrocarbon lubricant (A) becomes insufficient, while when the ratio is too large, there is a manufacturing problem in terms of reactivity and the viscosity is high. Has a tendency to get too high. When reacting 1 mol of castor oil with about 3 mol or more of fatty acid, at least a part of the fatty acid needs to be a condensable oxy fatty acid (castor oil fatty acid or hydrogenated castor oil fatty acid).

As the fatty acid or condensed fatty acid in (b2), those mentioned as the fatty acid or condensed fatty acid in (b1) can be used.

The alcohol in (b3) is monovalent,
Dihydric, trihydric, and tetrahydric alcohols are used, in particular trimethylolpropane, pentaerythritol, dipentaerythritol, neopentyl glycol, trimethylolethane, 2-ethylhexanol, isobutanol, sec-butanol, t- Those belonging to hindered alcohols or branched alcohols such as butanol, benzyl alcohol and alcohols by the Guerbet reaction are preferable.

As the ester (B), the above-mentioned ester (b
An ester (b4) having a structure in which at least a part of castor oil or castor oil fatty acid among 1), (b2), and (b3) is replaced with hydrogenated castor oil or hydrogenated castor oil fatty acid can be similarly used. However, it is required to have low temperature fluidity suitable for the intended use.

Esterification can be obtained by reacting each component under heating. This reaction may be carried out without a catalyst, or an acid catalyst (paratoluenesulfonic acid, sulfuric acid, hydrochloric acid,
It may be carried out in the presence of a general esterification catalyst such as phosphoric acid), a titanium-based catalyst, boron trifluoride, zinc chloride or sodium methylate.

The esterification reaction is usually carried out in an inert gas atmosphere. In the reaction, it is often preferable to add an appropriate amount of a refluxing solvent such as xylene and to remove water produced as a by-product from the system by azeotropic distillation. Reaction temperature is 150-250
C., especially 160 to 230.degree. C. in many cases. In some cases, the reaction may be performed under reduced pressure. Since it is not preferable that fatty acids and alcohol remain as unreacted substances,
If unreacted fatty acid or alcohol remains at the end of the reaction, it is desirable to remove the unreacted fatty acid or alcohol out of the system by means such as vacuum distillation.

It is particularly desirable that the above ester (B) has a hydroxyl value of 80 or less and an iodine value of 70 or less. When the hydroxyl value exceeds 80, the blending with the synthetic hydrocarbon lubricant (A) is limited, and it becomes difficult to obtain the desired property balance as a lubricant. On the other hand, when the iodine value exceeds 70, the oxidation stability becomes insufficient, and the lubricant is not suitable.

Synthetic hydrocarbon lubricant (A) and ester (B)
The blending ratio with is 95: 5 to 20:80, preferably 90:10 to 25:75 by weight. If the ratio of synthetic hydrocarbon lubricant (A) is too small, hydrolysis resistance and low temperature fluidity become problems, and synthetic hydrocarbon lubricant
If the proportion of (A) is too large, lubricity (especially pressure-resistant lubricity)
Will run out.

The composition comprising the above hydrocarbon-based lubricant (A) and ester (B) includes antioxidants, surfactants, oiliness improvers, extreme pressure agents, emulsifiers, rust inhibitors, etc. Lubricating materials such as mineral oils, animal and vegetable oils, esterified oils, polybutene or hydrogenated products thereof, and alkylbenzenes can be added as long as they can be blended with auxiliary agents or additives and do not impair the gist of the present invention. It can also be blended.

The lubricating composition of the present invention is a lubricating oil for automobiles (gasoline engine oil, diesel engine oil, two-cycle engine oil, LPG engine oil, rotary engine oil, automobile gear oil, automatic transmission oil, shock absorber oil). , Power steering oil, etc.), aircraft lubricating oil (aviation engine oil, aviation hydraulic oil, aviation gear oil, aviation instrument oil, etc.), marine lubricating oil (marine diesel engine oil, etc.), industrial lubricating oil (turbine Oil, industrial gear oil, hydraulic oil, compressor oil, bearing oil, sliding surface oil, etc., grease base oil (general grease base oil, rolling bearing grease base oil, vehicle chassis grease base oil, wheel bearing grease) It is particularly useful as a base oil, a grease base oil for concentrated lubrication, a high load grease base oil, etc.) and a plastic working oil (for can making, bending, etc.).

[0030]

The lubricating composition of the present invention has well-balanced basic required properties such as lubricity, hydrolysis resistance, heat resistance, and low temperature fluidity, and is advantageous in terms of cost. Automotive lubricating oil, aircraft lubricating oil, marine lubricating oil,
It has practicality as a lubricating composition for use in industrial lubricating oils, grease base oils, or plastic working oils.

[0031]

EXAMPLES The present invention will be further described with reference to examples.

<Synthetic Hydrocarbon Lubricant (A)> As the synthetic hydrocarbon lubricant (A), the following were prepared.

(A-1) α-olefin oligomer having a molecular weight of 568 (“Mobile SHF6 manufactured by Mobil Oil Co., Ltd.
1 ”, kinematic viscosity (JIS K 2283): 28.8 cSt / 40 ° C, viscosity index (J
IS K 2283): 136, pour point (JIS K 2269): -55 ° C or lower).

(A-2) Ethylene-α-olefin cooligomer (“Lucant HC manufactured by Mitsui Petrochemical Co., Ltd.
-10 ", kinematic viscosity (JIS K 2283): 60cSt / 40 ℃, viscosity index
(JIS K 2283): 150, pour point (JIS K 2269): -52.5
° C).

<Ester (B)> The following were synthesized as the esters (B) and (B '). (B) is an ester for Examples, and (B ') is an ester for Comparative Examples.

(B-1) A caster oil 93 was added to a reactor equipped with a stirrer, a thermometer, a nitrogen inlet tube, and a reflux condenser with a water test tube.
0 g (1 mol), capric acid 344 g (2 mol), xylene 70 ml and paratoluenesulfonic acid as catalyst
1.2 g was charged, and the reaction was carried out for 10 hours at 170 to 220 ° C. under a nitrogen stream while removing by-produced water under reflux of xylene. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C. to obtain an esterification reaction product having a hydroxyl value of 25.5 and an iodine value of 65.7.

(B-2) In a reactor, 930 g (1 mol) of castor oil, 344 g (2 mol) of capric acid, 2 stearic acids
84 g (1 mol), xylene 80 ml and paratoluenesulfonic acid 1.5 g were charged, and 170 to 22 under a nitrogen stream.
The reaction was carried out at 0 ° C. for 10 hours while removing water by-produced under xylene reflux to the outside of the system. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C. to obtain an esterification reaction product having a hydroxyl value of 3.5 and an iodine value of 53.1.

(B-3) Hydrogenated castor oil fatty acid 600 g (2 mol), capric acid 172 g (1 mol) and xylene 5
Charge 0 ml into the reactor and under a nitrogen stream at 200-220 ° C.
And react for 8 hours at an acid value of 79 corresponding to the fatty acid trimer.
To obtain a cap-type condensed fatty acid.

Then, 930 g (1 mol) of castor oil, 344 g (2 mol) of capric acid and 2.0 g of paratoluenesulfonic acid were charged into a reactor, and 180 to 2 were added under a nitrogen stream.
The reaction was carried out at 20 ° C for 10 hours. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C, and the hydroxyl value was 2.2 and iodine value was 4
An esterification reaction product of 0.7 was obtained.

(B-4) 750 g (2.5 mol) of castor oil fatty acid, 1500 g (5 mol) of hydrogenated castor oil fatty acid and 130 ml of xylene were charged into a reactor, and the mixture was stirred under a nitrogen stream at 20
Reaction was carried out at 0 to 220 ° C. for 8 hours to obtain a condensed fatty acid having an acid value of 60 corresponding to a fatty acid trimer.

Then, the reactor was charged with 837 g (0.9 mol) of castor oil, 93 g (0.1 mol) of hydrogenated castor oil and 3.0 g of paratoluenesulfonic acid, and the mixture was heated to 180-
The reaction was carried out at 220 ° C for 10 hours. After the reaction, temperature 170 ℃
Xylene was recovered under reduced pressure to obtain a hydroxyl value of 39.5 and an iodine value of
An esterification reaction product of 48.5 was obtained.

(B-5) Hydrogenated castor oil fatty acid 1800 g (6
Mol), 516 g of capric acid (3 mol), xylene 13
Charge 0 ml into the reactor and under a nitrogen stream at 200-220 ° C.
And reacted for 8 hours to obtain a cap type condensed fatty acid having an acid value of 65.0 corresponding to a fatty acid trimer.

Then, trimethylolpropane 1 was added to the reactor.
34 g (1 mol) and paratoluene sulfonic acid 2.2 g
Was charged and reacted at 180 to 220 ° C. for 10 hours under a nitrogen stream. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C. to obtain an oily esterified product having a hydroxyl value of 9.5 and an iodine value of 3.0.

(B-6) Castor oil fatty acid 300 g (1 mol), lauric acid 200 g (1 mol), xylene 40 ml
Was charged into a reactor, and under a nitrogen stream at 200 to 220 ° C., 6
After reacting for a time, a cap type condensed fatty acid having an acid value of 117.0 corresponding to a fatty acid dimer was obtained.

Then 111 g of isobutanol was added to the reactor.
(1.5 mol) and 1.2 g of paratoluenesulfonic acid were charged and reacted at 110 to 120 ° C. for 5 hours under a nitrogen stream. After the reaction, excess isobutanol was recovered under reduced pressure at a temperature of 120 ° C. to obtain an oily esterified product having a hydroxyl value of 0.8 and an iodine value of 67.3.

(B-7) Hydrogenated castor oil fatty acid 600 g (2 mol), capric acid 172 g (1 mol), xylene 50 ml
Was charged into a reactor, and the temperature was 8 at 200 to 220 ° C. under a nitrogen stream.
After reacting for a time, a cap type condensed fatty acid having an acid value of 79 corresponding to a fatty acid trimer was obtained.

Then, 130 g (1 mol) of 2-ethylhexyl alcohol and paratoluenesulfonic acid were added to the reactor.
Charge 0.9g, 10 at 180-220 ℃ under nitrogen stream
Allowed to react for hours. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C. to obtain an oily esterified product having a hydroxyl value of 15.0 and an iodine value of 2.0.

In the (B'-1) reactor, 516 g of capric acid (3
Mol), trimethylolpropane 134 g (1 mol),
50 ml of xylene and 0.6 g of para-toluenesulfonic acid were charged and reacted at 180 to 220 ° C. for 10 hours under a nitrogen stream. After the reaction, xylene was recovered under reduced pressure at a temperature of 170 ° C. to obtain an oily esterified product having a hydroxyl value of 10.0 and an iodine value of 0.2.

In the (B'-2) reactor, 202 g of sebacic acid (1
Mol), 325 g of 2-ethylhexyl alcohol (2.5
Mol) and 0.5 g of paratoluenesulfonic acid,
The reaction was carried out at 180 to 220 ° C. for 10 hours under a nitrogen stream.
After the reaction, excess 2-ethylhexyl alcohol was recovered under reduced pressure at a temperature of 200 ° C. to obtain a hydroxyl value of 1.5 and an iodine value of 0.3.
An oily esterified product of

<Preparation and Evaluation of Lubricant Composition> The above-mentioned synthetic hydrocarbon lubricant (A) is mixed with the esters (B) and (B ′) to prepare a lubricant composition, and the lubricant is prepared. The various properties were measured. The conditions and results are shown in Table 1. Regarding the fluidity at 0 ° C., since it is liquid at 0 ° C. in any case, the description in Table 1 is omitted.

[0051]

[Table 1] (A) and (B), (B ') Evaporation loss Hydrolysis Dynamic friction coefficient Load capacity and weight ratio (%) Rate (%) Number (kg / cm ² ) Example 1 (A-1) :( B-1) = 1: 1 0.27 50.3 0.11 6.0 Example 2 (A-1) :( B-1) = 3: 1 0.29 31.5 0.10 6.5 Example 3 (A-1) :( B-2) = 1 : 1 0.35 29.8 0.10 6.5 Example 4 (A-1) :( B-3) = 1: 3 0.66 27.7 0.11 4.5 Example 5 (A-1) :( B-4) = 2: 1 0.27 27.3 0.11 7.5 Example 6 (A-1) :( B-5) = 1: 1 0.32 9.9 0.10 7.0 Example 7 (A-1) :( B-6) = 1: 1 0.84 42.7 0.12 5.5 Example 8 (A- 1) :( B-7) = 1: 1 0.90 27.3 0.11 6.0 Example 9 (A-2) :( B-1) = 1: 1 0.39 46.0 0.11 4.5 Example 10 (A-2) :( B- 5) = 1: 1 0.76 18.6 0.11 5.5 Comparative Example 1 (A-1) :( B'-1) = 1: 1 1.51 82.8 0.12 4.0 Comparative Example 2 (A-1) :( B'-2) = 1 : 1 3.66 94.3 0.15 4.0 Comparative Example 3 (A-2) :( B'-1) = 1: 1 1.65 82.4 0.12 4.0 Control Example 1 (A-1) Single 3.57 0 0.22 3.0 Control Example 2 (A-2) Single 0.01 0 0.15 3.5

<Measurement Method> In Table 1, evaporation loss, hydrolysis rate, dynamic friction coefficient, and load bearing capacity are measured as follows.

[0053]Evaporation loss When 10g of lubricant was heated at 170 ° C for 24 hours
Weight loss (%) was measured. Hydrolysis resistance Collect 0.5g of sample into a 100cc Erlenmeyer flask and use 1 / 10N-
Add 25 ml of NaOH in ethanol and add 1 at 60 ° C.
After heating for a period of time, the decomposition rate (%) with respect to the saponification value was measured.
The smaller the decomposition rate, the better the hydrolysis resistance.Dynamic friction coefficient It measured at 25 degreeC using the Soda pendulum friction tester.Load capacity Using a Soda type four-ball friction tester, at 25 ° C, 200 rpm
It was measured in the case.

<Discussion> It can be seen from Table 1 that the lubricating compositions of the Examples have well-balanced basic required properties such as lubricity, hydrolysis resistance, heat resistance and low temperature fluidity. On the other hand, it can be seen that the lubricating compositions of Comparative Examples have insufficient heat resistance (large evaporation loss), poor hydrolysis resistance, and slightly low load bearing capacity. In the case of α-olefin oligomer, the synthetic hydrocarbon lubricant (A) alone has insufficient heat resistance (large evaporation loss), large dynamic friction coefficient, and insufficient load-bearing capacity. In the case of olefin cooligomers, the coefficient of dynamic friction is rather large,
The load-carrying capacity is also insufficient, and in any case, it cannot be said that the lubricating composition has the basic required properties in a well-balanced manner.

[0055]

EFFECTS OF THE INVENTION The lubricating composition of the present invention has well-balanced basic required characteristics such as lubricity, hydrolysis resistance, heat resistance, and low temperature fluidity, and is advantageous in terms of cost. In addition, it has practicality as a lubricating composition for use in automobile lubricating oil, aircraft lubricating oil, marine lubricating oil, industrial lubricating oil, grease base oil or plastic working oil.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location C10N 30:02 30:08 40:02 40:04 40:06 40:08 40:24 Z 40: 25 40:26 40:28 50:10

Claims (3)

[Claims] 1. A synthetic hydrocarbon lubricant (A) comprising an α-olefin oligomer or an ethylene-α-olefin cooligomer, an ester (b1) of castor oil and a fatty acid or a condensed fatty acid, a castor oil fatty acid and a fatty acid or Castor oil or ester of condensed fatty acid (b2), ester (b3) obtained by further reacting these ester (b1), (b2) with alcohol and the above-mentioned ester (b1), (b2), (b3) or 95: 5 by weight ratio with at least one ester (B) selected from the group consisting of hydrogenated castor oil or an ester (b4) having a structure in which at least part of castor oil fatty acid is replaced with hydrogenated castor oil or hydrogenated castor oil fatty acid A lubricious composition comprising a composition of 20:80. 2. The lubricating composition according to claim 1, wherein the ester (B) has a hydroxyl value of 80 or less and an iodine value of 70 or less. 3. The lubricating composition according to claim 1, which is used as an automobile lubricating oil, an aircraft lubricating oil, a marine lubricating oil, an industrial lubricating oil, a grease base oil or a plastic working oil.