JP2000169870A - Amino acid derivative type lubricant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lubricant that has high safety, excellent lubricity and is suitable in the field of metal working by using a specific N-acylated methionine. SOLUTION: This amino acid derivative type lubricant comprises an N- acylated methionine represented by the formula (R is a residual group after removing carboxyl group from fatty acid; M is H, a metal atom, ammonium), typically N-lauroylmethionine. The amount of this lubricant to be used is 0.01-20 wt.%, preferably 0.1-10 wt.%, based on the whole amount of lubricant. In the case of a water-based lubricant oil, this composition is diluted with water usually five-ten times. In a preferred embodiment, a friction releaser, an antioxidant, a rust-preventive agent and the like are added to this lubricant oil composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an amino acid derivative type lubricant which can be suitably used in the field of metal working and the like.

[0002]

2. Description of the Related Art In recent years, interest in global environmental protection and human body safety has been increasing, and products that are "friendly to humans and the earth" are attracting attention. Also in the field of lubricants, there is a demand for a highly safe product that has little effect on the human body and a highly biodegradable product that has little impact on the environment. In particular, water-based lubricating oils are widely used for applications that may come into contact with the human body, such as cutting and grinding metal working oils, rolling oils, and hydraulic oils, and therefore demands for safety are increasing. For example, chlorinated compounds such as chlorinated paraffins, which have been conventionally used as extreme pressure additives, are extremely excellent in lubricity and extreme pressure properties, but cause rust and are restricted in use due to dioxin problems. Is coming. Sulfur-based compounds are also excellent in lubricity and extreme pressure properties, but many have unique odors, and thus have many problems in lubrication applications that may come into contact with the human body.

[0003] On the other hand, as a lubricant free of such a problem, polyalkylene glycol can be cited, which is superior in safety as compared with the above-mentioned chlorinated compounds and sulfur-based compounds, but has a high lubricity. Inferior. Fatty acid soaps have high safety and good lubricity, but have the problem that they react with other metal ions to form water-insoluble metal soaps and form sludge.

[0004]

As a raw material for a highly safe lubricant, there is an amino acid. Amino acids are structural units of proteins and are important substances for constituting living tissues. Amino acid derivative-type lubricants using such amino acids as raw materials are expected to have high safety.
Conventionally known amino acid derivative type lubricants include the following. For example, Japanese Patent Application Laid-Open No. 55-90592
Japanese Patent Application Publication No. JP-A-2003-133125 discloses a lubricating oil additive comprising a magnesium salt of an α-amino acid N-carboxylate such as glycine and a method for producing the same. JP-A-61-241396
In this publication, a lubricant comprising an N-acylated basic amino acid such as N-lauroyl lysine, N-stearoyl lysine, N-lauroyl ornithine is disclosed. JP-A-10-195471 discloses a water-soluble processing oil comprising a salt of N-acylated leucine, N-acylated alanine, N-acylated aspartic acid, N-acylated glutamic acid, N-acylated lysine and the like. Have been.

[0005] However, these amino acid derivative-type lubricants are naturally high in safety but insufficient in lubricity and extreme pressure. Accordingly, an object of the present invention is to provide an amino acid derivative-type lubricant having high safety and excellent lubricity.

[0006]

That is, the present invention provides the following general formula (1):

[0007]

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(In the formula, R represents a residue obtained by removing a carboxyl group from a fatty acid, and M represents a hydrogen atom, a metal atom or ammonium.) A lubricant comprising an N-acylated methionine represented by the formula:

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the general formula (1), R represents a residue obtained by removing a carboxyl group from a fatty acid. R is preferably a residue obtained by removing a carboxyl group from a fatty acid having 8 to 24 carbon atoms, and the fatty acid may be either saturated or unsaturated, and may be linear or branched. If the carbon number of R is too small, lubricity is low and an odor may be generated. If the carbon number is too large, the solubility in water is reduced.

As fatty acids, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, erucic acid, linoleic acid, linolenic acid,
Examples include arachiic acid, gadrenic acid, behenic acid, erucic acid, lignoceric acid, seracoleic acid, cerotic acid, montanic acid, mericinic acid, celloplastic acid and the like.
Further, mixed fatty acids derived from natural fats and oils containing these fatty acids may be used. As natural oils and fats, for example, linseed oil, eno oil, deer oil, olive oil, cocoa butter, kapok oil, white mustard oil, sesame oil, rice bran oil, safflower oil,
Vegetable oils such as shea nut oil, cinnamon oil, soybean oil, teaseed oil, camellia oil, corn oil, rapeseed oil, palm oil, palm kernel oil, castor oil, sunflower oil, cottonseed oil, coconut oil, tree wax, peanut oil, etc. Horse fat, beef tallow, beef tallow, beef tallow, lard,
Animal fats and oils such as goat fat, sheep fat, milk fat, fish oil, and whale oil. When a mixed fatty acid is used, R represents the average value of the number of carbon atoms.

M represents a hydrogen atom, a metal atom or ammonium. Examples of the metal atom include lithium, sodium, alkali metal atoms such as potassium and the like, and examples of ammonium include ammonia, methylamine,
Dimethylamine, ethylamine, diethylamine, (iso) propylamine, di (iso) propylamine, monoethanolamine, N-methylmonoethanolamine,
N-ethyl monoethanolamine, diethanolamine, triethanolamine, monopropanolamine,
Dipropanolamine, tripropanolamine, 2-
Amino-2-methyl-1-propanol, 2-amino-
2-methyl-1,3-propanediol, aminoethylethanolamine, N, N, N ′, N′-tetrakis (hydroxyethyl) ethylenediamine, N, N,
Ammonium such as N ', N'-tetrakis (2-hydroxypropyl) ethylenediamine is exemplified, and an alkali metal atom or ammonium of an alkanolamine is most preferred.

The N-acylated methionine represented by the general formula (1) can be obtained by subjecting a fatty acid chloride and methionine to an acylation reaction in the presence of an alkali catalyst.
As the fatty acid chloride, the chlorides of the above-mentioned fatty acids can be used. In addition, R of the general formula (1) is determined by the kind of the fatty acid chloride used in the acylation reaction.

The temperature at which the acylation reaction is carried out is not particularly limited. However, if the reaction is carried out at a too low temperature, the reaction rate is low and the reaction is not efficient. Preferably,
It is more preferably performed at 10 to 90 ° C, and 20 to 80 ° C
Most preferably, The time for performing the acylation reaction is not particularly limited, but is preferably 10 minutes to 12 hours, more preferably 20 minutes to 8 hours, and still more preferably 30 minutes to
It takes about 6 hours. In addition, in the acylation reaction, it is preferable to adjust the pH in the reaction system to be alkaline with an alkali to promote the reaction and to add the reaction system to the reaction system. Examples of the alkali include sodium hydroxide and potassium hydroxide.

In the acylation, when a solvent is used, the reaction proceeds rapidly. As the solvent, for example, methanol, ethanol, 1-propanol, 2-propanol, butanol, ethylene glycol, diethylene glycol, dipropylene glycol, methoxyethanol, ethoxyethanol, butoxyethanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethyl ether, diethyl ether, Ethyl methyl ether, water and the like can be mentioned.

When producing the N-acylated methionine of the present invention, for the purpose of purification, treatment with an adsorbent, vacuum degassing,
It is preferable to perform steam distillation, washing with acidic water, methanol, or the like. The lubricant of the present invention can be used as an oily lubricating oil by being blended with a lubricating base oil, but since it is water-soluble, it is used as an aqueous lubricating oil by being added to a water-based composition. Is preferred.

The oil-based lubricating oil or aqueous lubricating oil of the present invention includes:
Depending on the purpose or use, for example, mineral oil, synthetic oil, other lubricants such as fats and oils, oily agents such as fatty acids, friction modifiers,
Can be used in combination with extreme pressure agents, antioxidants, detergents, dispersants, viscosity index improvers, defoamers, rust inhibitors, pour point depressants, emulsifiers, surfactants, rust inhibitors, preservatives, etc. it can. Oil-based lubricating oil is a lubricating base oil composed of mineral oil, synthetic oil or fats and oils,
It comprises the lubricant of the present invention and, if necessary, the above-mentioned various additives. The amount of the lubricant of the present invention is preferably 0.01 to 20% by weight, more preferably 0 to 20% by weight based on the total amount of the composition. 0.1 to 10% by weight. The aqueous lubricating oil is composed of water as a base component, the lubricant of the present invention, and the various additives described above as necessary.The blending amount of the lubricant of the present invention is preferably based on the total amount of the composition. It is 0.01 to 30% by weight, more preferably 0.1 to 20% by weight. In the case of an aqueous lubricating oil, such an undiluted solution is usually 5 to 10
Dilute about 0 times before use.

Mineral oils are those which are separated, distilled and refined from natural crude oils, and include paraffinic and naphthenic oils, or those obtained by hydrotreating or solvent-purifying them. These include mineral oils called so-called spindle oils, machine oils, turbine oils, and cylinder oils. Synthetic oil is a chemically synthesized lubricating oil, and includes poly-α-olefin, polyisobutylene (polybutene), diester, polyol ester,
Examples include phosphate esters, silicate esters, polyalkylene glycols, polyphenyl ethers, silicones, fluorinated compounds, alkylbenzenes, and the like.

Examples of fats and oils include linseed oil, eno oil,
Oitichika oil, olive oil, cocoa butter, kapok oil, white mustard oil, sesame oil, rice bran oil, safflower oil, shea nut oil, cinnamon oil, soybean oil, teaseed oil, camellia oil, corn oil, rapeseed oil, palm oil, palm Kernel oil, castor oil, sunflower oil, cottonseed oil, coconut oil, wood wax, vegetable oils such as peanut oil, horse fat, tallow, beef tallow, beef tallow, lard, goat tallow,
Animal fats and oils such as sheep fat, milk fat, fish oil and whale oil, and hydrides thereof.

As the oily agent, capric acid, caproic acid,
Fatty acids such as pelargonic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, linoleic acid, linolenic acid; dimer acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid , Carboxylic acids such as sebacic acid and dodecane diacid; lauryl alcohol, myristyl alcohol,
Alcohols such as palmityl alcohol, stearyl alcohol and oleyl alcohol; amines such as laurylamine, myristylamine, palmitylamine, stearylamine and oleylamine; amides such as laurylamide, myristylamide, palmitylamide, stearylamide and oleylamide Is mentioned.

Examples of the friction modifier include capric acid (mono, di, tri) glyceride and caproic acid (mono, di, tri).
Di, tri) glyceride, caprylic acid (mono, di, tri)
Glyceride, lauric acid (mono, di, tri) glyceride, myristic acid (mono, di, tri) glyceride, palmitic acid (mono, di, tri) glyceride, stearic acid (mono, di, tri) glyceride, oleic acid (mono) ,
Esters such as di, tri) glyceride; metal salts such as sulfurized oxymolybdenum dialkyl dithiocarbamate, sulfurized oxymolybdenum dialkyl dithiophosphate, zinc dialkyl dithiophosphate, zinc dialkyl dithiocarbamate, polyol ethers, polyethers and the like.

Examples of extreme pressure agents include sulfurized olefins,
Sulfurized paraffin, Sulfurized polyolefin, Sulfurized lard, Sulfurized fish oil, Sulfurized whale oil, Sulfurized soybean oil, Sulfurized pinene oil, Sulfurized phenol, Sulfurized alkylphenol, Sulfurized fatty acid, Dialkyl polysulfide, Dibenzyl disulfide, Diphenyl disulfide, Polyphenylene sulfide, Alkyl mercaptan, Alkylsulfone Acid, dithiocarbamate, 1,3,4-thiadiazole derivative,
Sulfur compounds such as thiuram disulfide; butyl (thio, dithio) phosphate, hexyl (thio, dithio)
Phosphate, octyl (thio, dithio) phosphate, 2-ethylhexyl (thio, dithio) phosphate, nonyl (thio, dithio) phosphate, decyl (thio, dithio) phosphate, lauryl (thio, dithio)
Phosphate, myristyl (thio, dithio) phosphate, palmityl (thio, dithio) phosphate, stearyl (thio, dithio) phosphate, oleyl (thio,
(Thio, dithio) phosphate compounds such as dithio) phosphate, phenyl (thio, dithio) phosphate, and cresyl (thio, dithio) phosphate.

As the antioxidant, for example, 2,6-di-
tert.-butylphenol, 2,6-di-tert.
-Butyl-p-cresol, 2,6-di-tert.-
Butyl-4-ethylphenol, 2,4-dimethyl-6
-Tert.-butylphenol, 4,4'-methylenebis (2,6-di-tert.-butylphenol),
4,4'-bis (2,6-di-tert.-butylphenol), 2,2'-methylenebis (4-methyl-6-
tert.-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert.-butylphenol), 4,4′-butylidenebis (3-methyl-6-t)
ert.-butylphenol), 2,2′-methylenebis (4-methyl-6-cyclohexylphenol),
2,6-bis (2'-hydroxy-3'-tert.-
Butyl-5'-methylbenzyl) 4-methylphenol, 3-tert.-butyl-4-hydroxyanisole, 2-tert.-butyl-4-hydroxyanisole, 4,4'-thiobis (3-methyl-6- tert.
-Butylphenol), 4,4'-thiobis (2-methyl-6-tert.-butylphenol), 2,2'-
Thiobis (4-methyl-6-tert.-butylphenol), 2,6-di-tert. -Butyl-α-dimethylamino-p-cresol, 2,6-di-tert. ―
Butyl-4 (N, N'-dimethylaminomethylphenol), bis (3,5-di-tert.-butyl-4-hydroxybenzyl) sulfide, tris ｛(3,5-
J-tert. -Butyl-4-hydroxyphenyl) propionyl-oxyethyl diisocyanurate, tris (3,5-di-tert.-butyl-4-hydroxyphenyl) isocyanurate, 1,3,5-tris (3 ′, 5′- Di-tert.-butyl-butyl-4-
Hydroxybenzoyl) isocyanurate, bis 2-
Methyl-4- (3-n-alkylthiopropionyloxy) -5-tert. -Butylphenyl disulfide, 1,3,5-tris (4-di-tert.-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, tetraphthaloyl-di (2,6-dimethyl-4) -Tert.-butyl-3-hydroxybenzyl sulfide), 6- (4-hydroxy-3,5-di-t)
ert. -Butylanilino) -2,4-bis (octylthio) -1,3,5-triazine, 2,2-thio- ｛diethyl-bis-3- (3,5-di-tert.-butyl-4-hydroxyphenyl )｝ Propionate, N,
N'-hexamethylenebis (3,5-di-tert.-
Butyl-4-hydroxy-hydrocinamide), 3,5-
J-tert. -Butyl-4-hydroxy-benzyl-
Phenolic antioxidants such as phosphoric diester, bis (3-methyl-4-hydroxy-5-tert.-butylbenzyl) sulfide;

1-naphthylamine, phenyl-1-naphthylamine, p-octylphenyl-1-naphthylamine, p-nonylphenyl-1-naphthylamine, p-dodecylphenyl-1-naphthylamine, phenyl-2-
Naphthylamine-based antioxidants such as naphthylamine;
N'-diisopropyl-p-phenylenediamine, N,
N'-diisobutyl-p-phenylenediamine, N,
N'-diphenyl-p-phenylenediamine, N, N '
-Di-β-naphthyl-p-phenylenediamine, N-phenyl-N'-isopropyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, N-1,3-dimethylbutyl-N Phenylenediamine antioxidants such as' -phenyl-p-phenylenediamine, dioctyl-p-phenylenediamine, phenylhexyl-p-phenylenediamine, phenyloctyl-p-phenylenediamine; dipyridylamine, diphenylamine, p, p'- Di-n-butyldiphenylamine, p, p'-di-tert. -Butyldiphenylamine, p, p'-di-tert. -Pentyldiphenylamine, p, p'-dinonyldiphenylamine, p, p'-didecyldiphenylamine, p, p'-
Diphenylamine antioxidants such as didodecyldiphenylamine, p, p'-distyryldiphenylamine, p, p'-dimethoxydiphenylamine, 4,4'-bis (4-α, α-dimethylbenzoyl) diphenylamine and p-isopropoxydiphenylamine Agents and the like.

Examples of the detergent or rust inhibitor include calcium sulfonate, calcium phenate, calcium salicylate, magnesium sulfonate, magnesium phenate, magnesium salicylate, barium sulfonate, barium phenate, and barium salicylate. Examples of the dispersant include polyalkenyl succinimide, polyalkenyl succinimide boride, benzylamine and the like. Examples of the viscosity index improver include poly (meth) acrylate, polyisobutylene, polystyrene, ethylene-propylene copolymer, styrene-isobutylene copolymer and the like.

Examples of the surfactant include polyethylene glycol, polyethylene glycol monoalkyl (aryl) ether, polyethylene glycol dialkyl (aryl) ether, polyoxyethylene polyoxypropylene copolymer, polyol ester, polyether polyol, alkanolamide, Examples thereof include alkylbenzene sulfonic acid and petroleum sulfonate. These surfactants may also act as an oil agent or an emulsifier.

The lubricant of the present invention can be used by being added to lubricating oils for various uses. For example, industrial lubrication oil, turbine oil, machine oil, bearing oil, compressor oil, hydraulic oil, hydraulic oil,
Internal combustion engine oil, refrigerator oil, gear oil, automatic transmission oil (AT
F), continuous variable continuously variable transmission oil (CVT oil), transaxle fluid, metalworking oil, and the like. It can be used by adding to various greases such as sliding bearings, rolling bearings, gears, universal joints, torque limiters, automotive constant velocity joints (CVJs), ball joints, wheel bearings, constant velocity gears, and transmission gears. .

[0027]

The present invention will be described more specifically with reference to the following examples. In the following examples, parts and percentages are by weight unless otherwise specified. (Example 1) First, the physical properties of the lubricant itself of the present invention were evaluated.

<Water solubility> 1% of each of the present invention products 1 to 3 or comparative products 1 to 3 shown in Table 1 is dissolved in ion-exchanged water,
After leaving for 1 hour at each temperature shown in Table 1, the appearance was visually observed. ：: transparent ×: turbid <Lubricity> 1% of each of the present invention products 1 to 3 or comparative products 1 to 3 shown in Table 1 was dissolved in ion-exchanged water by 1%, and using a shell-type high-speed four-ball testing machine. , Load 490N, rotation speed 1,500
The friction coefficient and the wear scar diameter were measured under the conditions of rpm and a test time of 60 seconds. Table 1 shows the results of these evaluations.

[0029]

[Table 1]

(Example 2) Next, the product 1 of the present invention shown in Table 1
Using the lubricants of Nos. 1 to 3 or Comparative Products 1 to 3, stock solutions of aqueous lubricating oils having the following formulations were prepared, and their performances were evaluated.

[0031]

<Appearance> The appearance of the aqueous lubricating oil stock solution was visually observed. Also, the appearance of the stock solution after standing in a low-temperature bath at 0 ° C. for one week was visually observed. <Cutting test> Precision automatic lathe, high speed steel bite SKH-
Using 4A, a steel material was cut. The above stock solution was diluted 20 times with water and used as a processing oil.
C was cut. The cutting speed is 30m / min.
Evaluation was made based on tool life and surface roughness. The tool life was determined by the time until the cutting tool became worn or the cutting became impossible due to wear, and the surface roughness was visually observed for the presence or absence of scratches on the surface of the cut surface. ：: No scratch on surface ×: Fine scratches These evaluation results are shown in Table 2.

[0033]

[Table 2]

[0034]

The effect of the present invention is to provide an amino acid derivative type lubricant having high safety and excellent lubricity.

Claims (1)

[Claims] 1. The following general formula (1): (In the formula, R represents a residue obtained by removing a carboxyl group from a fatty acid, and M represents a hydrogen atom, a metal atom or ammonium.) A lubricant comprising an N-acylated methionine represented by the following formula: