JPH1135964A - Composition for lubricant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubricant blended with a highly abrasion-resistant preservative which does not generate a sludge even if the oil is contaminated with a lubricant oil having another preservative and also dose not reduce the extreme pressure property even if the preservative is blended with a lubricant oil containing an extreme pressure agent although the extreme pressure property of some lubricant oils having a extreme pressure agent is reduced when a preservative is blended to the lubricant oils. SOLUTION: A base oil contains, as the essential components, 0.01-5.0 wt.% of an acidic phosphoric acid ester mixture of formula I, (R1 O)2 -PO(OH) and formula II, R1 O-PO(OH)2 and 0.1-2.0 mol per a mol of the added acidic phosphoric acid ester of an amine of formula III, R2 NH(CH2 )n NH2 and/or formula IV, R3 N(CH3 )2 . In the formulae, R1 stands for a 12-22C branched saturated hydrocarbon group, R2 and R3 each stands for an 8-22C linear saturated hydrocarbon group or a linear unsaturated hydrocarbon group. Two R1 s may be the same and may be different from each other. The suffix (n) stands for an integer of 1-6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic oil, a compressor oil, a gear oil, an industrial machine oil, a bearing oil, which has a lubricating property and a rust preventive property and is excellent in stability against mixing of different kinds of oils. The present invention relates to a lubricating oil composition that can be widely used as a lubricating oil for general industrial machines such as turbine oil.

[0002]

2. Description of the Related Art Lubricating oils for industrial machinery, such as hydraulic fluids, compressor oils, gear oils, industrial machine oils, bearing oils, turbine oils, etc., are required to have excellent rust prevention and lubricity such as extreme pressure resistance and wear resistance. However, various types of dedicated lubricating oils containing various additives are used in view of the type of machine used and the variety of use conditions. However, depending on the type of additive, lubricating properties may be reduced, or when lubricating oils with different compositions are mixed with each other, the additives may react with each other and generate sludge insoluble in the lubricating oil, resulting in malfunction of equipment. Or clogging of the filter may occur.

In general, overbased alkaline earth metal salts such as salicylates, sulfonates, phenates, and soaps, carboxylic acids, partial esters of polycarboxylic acids, and amine salts of acidic phosphoric esters are widely used as rust preventives for lubricating oils. in use. When lubricating oils containing these different types of rust preventive agents are mixed with each other, the additives react with each other and generate precipitates, causing malfunctions in equipment, clogging of filters, or the original lubricating oil. Often, the lubricating performance of the steel is significantly reduced. For example, machine tool oils and automotive lubricating oils containing a hydraulic fluid containing a polycarboxylic acid partial ester or acidic phosphate ester as a rust preventive, and an overbased metal sulfonate as a rust preventive or detergent. When the oil is mixed, a metal compound insoluble in the hydraulic oil is generated, and the filter of the hydraulic device is clogged, or the operation of the hydraulic valve is malfunctioned, so that the normal operation of the hydraulic device cannot be performed. Also, when a carboxylic acid or a partial ester of a polycarboxylic acid is added as a rust inhibitor to a lubricating oil containing an extreme pressure agent, the extreme pressure property may be reduced.

[0004]

SUMMARY OF THE INVENTION The present invention does not generate sludge even if a lubricating oil having a different type of rust inhibitor is mixed in, and a rust inhibitor is added to a lubricating oil containing an extreme pressure agent. Extreme pressure may be reduced when a carboxylic acid or a partial ester of a polycarboxylic acid is blended, but the present invention does not cause a decrease in extreme pressure in such a case,
It is an object of the present invention to provide a lubricating oil having good wear resistance and extreme pressure.

[0005]

Means for Solving the Problems Conventionally, acidic phosphate esters have been used as extreme pressure agents and rust preventives in lubricating oils for industrial machinery, and as mixed esters of di and mono.
The present inventors have found that by using an acidic phosphate ester having a specific structure and an amine having a specific structure as the acidic phosphate ester, a lubricating oil that has solved the above-mentioned problems can be obtained. The present invention was able to be reached.

The acidic phosphoric acid ester having the above specific structure is a mixture of a dialkyl acid phosphoric acid ester represented by the following formula (1) and a monoalkyl acid phosphoric acid ester represented by the following formula (2). Further, the amine having the specific structure is an amine represented by the following formulas (3) and (4).

[0007]

Embedded image (R ₁ O) ₂ —PO (OH) (1) R ₁ O—PO (OH) ₂ (2) R ₂ NH (CH ₂ ) nNH ₂ (3) R ₃ N (CH ₃ ) ₂ (4) [In the formula, R ₁ represents a branched saturated hydrocarbon group having 12 to 22 carbon atoms, and R ₂ and R ₃ represent a straight-chain saturated hydrocarbon group having 8 to 22 carbon atoms or a linear unsaturated hydrocarbon group. Represents a hydrocarbon group. The two R _{1 's} may be the same or different. n
Represents a positive number of 1 to 6. ]

In the mixed acidic phosphate ester used in the prior art, the reaction of the overbased alkaline earth metal salt with the rust inhibitor produces an alkaline earth metal phosphate insoluble in lubricating oil. The acidic phosphoric acid ester of the formulas (1) and (2) is obtained by converting the formula (3) and / or the formula (4)
By using in combination with an amine, sludge precipitation can be suppressed even when foreign oil containing an alkaline earth metal salt is mixed. In order for the present invention to achieve the intended object, the acidic phosphoric acid alkyl ester of the above formulas (1) and (2) has a branched structure having 12 or more carbon atoms, The amine to be combined with the alkyl ester must be the amine of the formula (3) and / or the formula (4), and other amines do not exhibit the effect of controlling sludge at the time of mixing different kinds of oils.

The lubricating property is improved as the number of carbon atoms in the alkyl of the acidic phosphate ester represented by the above formulas (1) and (2) is smaller. Conversely, if the number of carbon atoms is too large, the lubricity is impaired. Therefore, an alkyl group having preferably 12 to 22 carbon atoms, more preferably an alkyl group having 12 to 18 carbon atoms. In addition, the ratio of the acidic phosphoric acid ester of the above formulas (1) and (2) is usually such that the molar concentration of the monoester of the above formula (2) is 70
% Or less, and if it exceeds 70 mol%, the compatibility with alkaline earth metal salts is poor. The total amount of the acidic phosphoric acid esters of the above formulas (1) and (2) is 0.01 to 5.0% by weight, preferably 0.02 to 1.0% by weight. If the amount of the acidic phosphoric acid ester is too small, the required rust prevention and lubricity cannot be obtained, while if it is too large, the corrosion resistance and hydrolysis stability of the lubricating oil are impaired. The compounding amount of the amine of the formula (3) and / or the formula (4) is
1/10 to 2.0 mol, especially 1/4 to 2.0 mol, based on the total mol number of the acidic phosphoric acid ester of the above formulas (1) and (2).
1.0 mole is preferred. When the compounding amount of the amine of the formula (3) and / or the formula (4) is less than 1/10, there is no rust preventive property and no sludge suppression effect at the time of intrusion of the alkaline earth metal salt rust preventive agent. If it exceeds 0.0 mol, the lubricating effect of the acidic phosphoric acid esters of the above formulas (1) and (2) tends to be impaired, or the thermal oxidation stability of the lubricating oil tends to be reduced.

The base oil used in the present invention includes, for example, mineral oil, vegetable oil, synthetic ester or synthetic hydrocarbon base oil.

The lubricating oil of the present invention has the above formulas (1) and (2)
In addition to the acid phosphate ester of formula (3) and / or the amine of formula (4), an antiwear agent, an extreme pressure agent, a friction reducing agent, a metal deactivator, an antioxidant, a pour point depressant , A viscosity index improver, an adhesion improver, a dispersant, an antifoaming agent and the like may be appropriately compounded.

The lubricating oil of the present invention has extreme pressure properties and rust prevention properties, and is excellent in stability against mixing of different types of oils, hydraulic oil, compressor oil, gear oil, machine tool oil, bearing oil, turbine. It is useful as a lubricating oil composition for industrial machines such as oil.

[0013]

The present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples.

Comparative Examples 1 to 8 and Examples 1 to 6 Highly refined mineral oil having a kinematic viscosity at 40 ° C. of 31 cSt was used as a base oil, and the components shown in Table 1 were added, and no rust inhibitor was added. A basic lubricating oil composition was prepared. Comparative Examples 1 to 8 shown in Tables 2 to 3 were used as rust inhibitors in this basic lubricating oil composition.
And the components of Examples 1 to 6 shown in Table 4 were added to prepare test oils of Examples and Comparative Examples having a viscosity of 40 to 33 cSt at 40 ° C.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

[Table 3]

[0018]

[Table 4]

The performance of the test oil used in the present invention was evaluated by the following test methods. <Rust prevention test> According to the lubrication oil rust prevention test method specified in JIS K2510, 30 ml for 300 ml of lubricating oil
The rust prevention performance was evaluated when distilled water was added and when 30 ml of artificial seawater was added. <Shell 4-ball abrasion test> A test was performed for 30 minutes at a load of 40 kgf, a rotation speed of 1800 rpm, and an oil temperature of 75 ° C., and the wear scar diameter of the fixed ball after the test was measured.

<Filter clogging test> In order to investigate the tendency to cause troubles due to precipitation of insoluble matter due to mutual reaction between additives of the lubricating oil when a different type of lubricating oil is mixed into the lubricating oil, thereby clogging the filter of the machine. Then, lubricating oils A and B having different additive compositions were mixed in the same amount with the test oil, and 0.1% by weight of water was added to the mixed oil and stirred to reproduce the actual use situation. Sealed at 70 ° C 7
After standing for 2 hours, the mixed oil was 660 mmHg at room temperature using a 1.2 micrometer membrane filter.
The time (seconds) required to filter 300 ml of the mixed oil under a differential pressure of 3 was measured. The composition of the lubricating oil A and the lubricating oil B mixed as the different oils in the test oil is as shown below.
Was mixed with a partial ester of alkenyl succinic acid (Lubrizol 859, manufactured by Lubrizol), and lubricating oil B was mixed with overbased calcium sulfonate (Metal cleaning agent, Oroa 247E, manufactured by Olonite) as a rust preventive. One used.

<Composition of Lubricating Oil A (Non-Zinc Abrasion-Resistant Hydraulic Fluid)> Leophos 65 1.0% by weight (triaryl phosphate-based antiwear agent manufactured by Ajinomoto Co.) Ethyl 4701 1.0% by weight (manufactured by Ethyl Corporation) Phenol antioxidant) Lubrizol 859 0.1% by weight (Polyvalent carboxylic acid partial ester-based rust inhibitor manufactured by Lubrizol) PAM141 0.5% by weight (Polymethacrylate-based pour point depressant manufactured by Shell Japan) Aditin RC4901 0.05% by weight (Triazole corrosion inhibitor manufactured by Rhein-Kemi Co.) Hydrorefined paraffinic base oil (32 cSt 40 ° C.) 97.35% by weight <Lubricant B (engine oil and hydraulic oil for construction machinery) )> Oroa 267 1.5% by weight (Zinc dialkyldithiophosphate-based antiwear agent manufactured by Oronite) Oroa 247E 4 0.0% by weight (Calcium sulfonate-based rust preventive / cleaning agent manufactured by Olonite) Oroa 373 3.0% by weight (succinimide-based dispersant manufactured by Olonite) TLA347 6.0% by weight (OCP viscosity manufactured by Texaco) Index improver) Solvent refined paraffinic base oil (30 cSt 40 ° C.) 85.5% by weight

Commercially available acidic phosphoric acid esters and amines used for preparing the sample oils of the above Comparative Examples and Examples were (1) Sapho Chemical Co., Phoslex-A10,
(2) Sakai Chemical Co., Phoslex-A13, (3) Sakai Chemical Co., Phoslex-A18D, (4) Rohm and Hass Co., Primen-81R, (5) Kao Co.,
Diamine-RRT, (6) Hoslex-, manufactured by Sakai Chemical Co.
A180L, (7) Famine DM86 manufactured by Kao Corporation was used.

[0023]

[Table 5]

[0024]

[Table 6]

[0025]

[Table 7] From Tables 5 and 6, the acidic phosphate ester having a straight-chain hydrocarbon group or a branched hydrocarbon group having 10 or less carbon atoms has an amine represented by the formula (3) and / or (4). Table 7 shows that even when lubricating oil B containing an alkaline earth metal salt-based rust inhibitor is mixed, clogging of the filter may occur even when combined with And a specific acidic phosphoric acid ester of the formula (1) and the formula (2) having a hydrocarbon group having 12 or more carbon atoms and an amine of the formula (3) and / or the formula (4) It can be seen that the corrosiveness, lubricity, rust prevention, and filter clogging when different types of oils are mixed are remarkably and simultaneously improved by the combined use.

[0026]

According to the present invention, even when lubricating oils having different compositions are mixed, additives react with each other to generate sludge insoluble in the lubricating oil, thereby causing malfunction of equipment and clogging of filters. There is provided a lubricating oil which has no lubrication and can be widely used for general industrial machines having good lubricity.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI C10N 30:06 30:12 40:02 40:06 40:08

Claims (1)

[Claims] 1. An acid phosphate mixture represented by the following general formulas (1) and (2): 0.01 to 5.0% by weight;
The amine of the following general formula (3) and / or the following general formula (4) is added to the molar number of the acidic phosphoric acid ester added in 1 /
An industrial lubricating oil composition comprising 10 to 2.0 mol as an essential component in a base oil. Embedded image (R ₁ O) ₂ —PO (OH) (1) R ₁ O—PO (OH) ₂ (2) R ₂ NH (CH ₂ ) nNH ₂ (3) R ₃ N (CH ₃ ) ₂ (4) [In the formula, R ₁ represents a branched saturated hydrocarbon group having 12 to 22 carbon atoms, and R ₂ and R ₃ represent a straight-chain saturated hydrocarbon group having 8 to 22 carbon atoms or a linear unsaturated hydrocarbon group. Represents a hydrocarbon group. The two R _{1 's} may be the same or different. n
Represents a positive number of 1 to 6. ]