WO2008038571A1 - Hydraulic oil composition - Google Patents

Abstract

A hydraulic oil composition obtained by blending a base oil having a sulfur content of less than 0.03% by mass, a content of saturates of 90% by mass or above, a viscosity index of 80 or above and an absolute viscosity at 40°C of 1 to 1000mPa s with (A) 1 to 20% by mass of a polymethacrylate-type viscosity index improver having a weight-average molecular weight of 10,000 to 50,000, (B) 0.005 to 5% by mass of an acid amide, (C) 0.005 to 5% by mass of (c-1) a specific hydrogenphosphate ester and/or (c-2) a specific hydrogenphosphite ester and (D) 0.005 to 5% by mass of at least one member selected from among polyhydric alcohol esters, alkanolamines, olefin sulfides, and thiocarbamates. The hydraulic oil composition exerts satisfactory and well-balanced properties essential to hydraulic oil which include energy saving, heat stability (sludge resistance), prevention of wear and scuffing, water shedding, and friction reduction in sliding parts.

Description

 Specification

 Hydraulic fluid composition

 Technical field

 [0001] The present invention relates to a hydraulic fluid composition, more specifically, good energy saving, thermal stability (sludge resistance), wear resistance, seizure resistance (scuffing resistance), water separation and sliding parts The present invention relates to a hydraulic fluid composition that is suitable for use in the hydraulic machine field, machine tool field, industrial machine field, and the like.

 Background art

 [0002] Hydraulic fluid is a power transmission fluid used for power transmission, force control, buffering, etc. of hydraulic systems such as hydraulic equipment and devices, and also serves as a lubrication function for sliding parts. Inside, there are sliding parts such as metal metal and metal rubber (resin) on pumps, control valves and hydraulic cylinders. The hydraulic fluid used in such a hydraulic circuit is required to have good friction characteristics such as wear resistance, seizure resistance, and friction reduction at these sliding portions.

 In recent years, hydraulic operation systems have become more sophisticated, and there are cases where the flow rate and direction of the hydraulic system are controlled by spool valves, etc., and servo valves are installed for high-speed and precise control. There are many. The performance of such a spool valve or servo valve is greatly reduced if sludge is generated in the hydraulic fluid, so that the hydraulic fluid used has excellent friction characteristics and generates sludge. There is a strong demand for hydraulic fluids that have excellent sludge resistance that can be suppressed.

 Furthermore, from the standpoint of energy saving, it has become necessary to improve the performance of hydraulic fluids by reducing the resistance at the sliding part and reducing the loss energy and suppressing the oil temperature rise.

Conventionally, zinc dithiophosphate (ZnDTP) has been widely used as an antiwear agent for hydraulic fluids. However, ZnDTP causes sludge generation and cannot be used for a long period of time when blended with hydraulic fluid. Also, the wear prevention effect of using ZnDTP is The force S due to the formation of a hard coating such as iron phosphate on the surface, and the formation of the coating increases the friction coefficient of the sliding part, which may not be preferable from the viewpoint of energy saving.

 Therefore, hydraulic fluids using so-called non-zinc-based anti-wear agents that do not use ZnDTP have been studied.

 For example, hydraulic fluids containing aromatic phosphate esters, phosphites and their amine salts, thiophosphates, β-dithiophosphorylated propionic acid compounds, etc. as antiwear agents instead of ZnDTP have been proposed ( For example, Patent Documents 12 and 3)

 However, these hydraulic fluids do not satisfy the friction characteristics such as sludge resistance (sludge suppression) and wear resistance! /. There is still room for improvement as a hydraulic fluid that can be

[0004] Further, instead of ZnDTP, a composition using a combination of an antioxidant, a phosphorus-based and / or sulfur-based compound, N-oleylsarcosine, and the like (see, for example, Patent Document 4), phosphorus A composition (for example, see Patent Document 5) containing a combination of a contained carboxylic acid compound and a dispersion-type viscosity index improver is disclosed.

 However, even these hydraulic fluids cannot be said to have sufficient friction properties such as sludge resistance (sludge suppression) and wear resistance.

 Therefore, it is required for hydraulic fluids, such as energy saving, thermal stability (sludge resistance), wear resistance, seizure resistance (scuffing resistance), water separation and sliding friction reduction. However, the current situation is that we cannot find anything that satisfies the balance.

Patent Document 1: Japanese Patent Laid-Open No. 10-67993

 Patent Document 2: JP-A-11 217577

 Patent Document 3: Japanese Patent Laid-Open No. 2002-265971

 Patent Document 4: Japanese Patent Laid-Open No. 2002-129180

 Patent Document 5: Japanese Unexamined Patent Publication No. 2005-307203

Disclosure of the invention Problems to be solved by the invention

[0006] Under such circumstances, the present invention requires energy saving, thermal stability (sludge resistance), wear resistance, seizure resistance (scuffing resistance), water required for hydraulic fluids. It is an object of the present invention to provide a hydraulic fluid composition that satisfies a good balance between separability and sliding portion friction reduction.

 Means for solving the problem

[0007] As a result of intensive studies to develop a hydraulic fluid composition that satisfies the required performance of hydraulic fluid in a well-balanced manner, the present inventors have determined that the molecular weight of the base oil having a specific property is specific. By blending the polymetatalylate viscosity index improver, the acid amide compound, the specific phosphate ester compound, etc., and the specific lubricity improver in a certain ratio at a predetermined ratio, the purpose is achieved. I found that it can be achieved. The present invention has been completed based on such knowledge.

 That is, the present invention

 [0008] [1] Sulfur content of less than 0.03 mass%, saturation content of 90 mass% or more, viscosity index of 80 or more and an absolute viscosity at 40 ° C of 1 to; a base oil having the property of lOOOmPa's;

 (A) 1 to 20% by mass of a polymetatalylate viscosity index improver having a weight average molecular weight of 10,000 to 50,000

 (B) acid amide compound 0.005-5 mass%

 (C) (c 1) General formula (II 1)

[0009] [Chemical 1]

(In the formula, R ¹ represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ² represents a hydrocarbon group having 1 to 18 carbon atoms.)

 An acidic phosphate compound represented by the formula: and / or (c 2) the general formula (式 — 2)

[0010] [Chemical 2]

(In the formula, R ³ represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ⁴ represents a hydrocarbon group having 1 to 18 carbon atoms.)

 An acidic phosphite compound represented by the formula 0.005 to 5% by mass,

 (D) a hydraulic fluid composition comprising 0.005 to 5% by mass of at least one selected from polyhydric alcohol esters, alkanolamines, olefin sulfides, and thiocarbamate compounds; and

 [2] Furthermore, (E) an amine salt of an acidic phosphate compound and a general formula (IV)

[0011] [Chemical 3]

R ⁷ — 0 ヽ

R ⁸ -0— P = 0 "姻

R ⁹ — 0

(Wherein R ^{7 to} R ⁹ each independently represent a hydrocarbon group having 1 to 18 carbon atoms.) At least one selected from a phosphate triester compound represented by the formula 0.005 to 5 mass % Of the hydraulic fluid composition according to the above [1],

 Is to provide.

 The invention's effect

 [0012] According to the present invention, good energy saving, thermal stability (sludge resistance), wear resistance, seizure resistance (scuffing resistance), water separation, friction reduction of sliding parts, etc. It is possible to provide a hydraulic fluid composition that is suitably used in the fields of hydraulic machinery, machine tools, industrial machinery, and the like.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0013] The hydraulic fluid composition of the present invention comprises a base oil, (A) a polymetatalate-based viscosity index improver, (B) an acid amide compound, and (C) (c 1) an acidic phosphate compound. And / or (c 2) a composition comprising an acidic phosphite compound and (D) a lubricity improver. The base oil used in the hydraulic fluid composition of the present invention has a sulfur content of less than 0.03 mass%, a saturation content of 90 mass% or more, a viscosity index of 80 or more, and an absolute viscosity at 40 ° C of 1 to; It needs to be 100 OmPa · s.

 If the sulfur content of the base oil is 0.03 mass% or more, or if the saturation content is less than 90 mass%, the oxidation stability is poor and the acid value rises and sludge is generated and The corrosiveness to be increased becomes large, and the effect of the present invention is not sufficiently exhibited. The sulfur content is preferably 0.02% by mass or less, more preferably 0.01% by mass or less. Further, the saturated content is preferably 95% by mass or more, more preferably

It is 98 mass% or more.

 The sulfur content is a value measured according to JIS K 2541, and the saturated content is a value measured according to ASTM D 2007.

 Furthermore, if the base oil has a viscosity index of less than 80, the viscosity at high temperatures may be low and the lubrication performance may be reduced.On the other hand, the viscosity may be high at low temperatures, resulting in poor suction of the pump. is there. From the viewpoint of widening the usable temperature range from low temperature to high temperature, the viscosity index is preferably 100 or more, more preferably 120 or more.

 The viscosity index is a value measured according to “Petroleum product kinematic viscosity test method” defined in JIS K 2283.

 If the base oil has an absolute viscosity less than mPa's at 40 ° C, the lubrication performance is inferior, abnormal wear or seizure may occur, and there is a high risk of fire. On the other hand, if it exceeds lOOOmPa's, the viscous resistance at low temperatures increases, which makes it difficult to suck into the pump and may cause malfunction of the machine. From the viewpoint of friction characteristics, fire hazard and viscous resistance at low temperatures, the absolute viscosity at 40 ° C is preferably 3 to 500 mPa's, and 5 to 300 mPa's is more preferable 10 to 150 mPa's Is more preferable.

As the base oil, any of mineral oil and synthetic oil can be used as long as it has the above properties. There are no particular restrictions on the type of mineral oil or synthetic oil, etc. Examples of mineral oils include paraffin-based mineral oils, intermediate-based mineral oils, or naphthenic groups obtained by ordinary refining methods such as solvent refining and hydrogenation refining. Mineral oil and the like. Synthetic oils include, for example, polybutene, polyolefin [α-olefin (co) polymer], various esters (for example, polyol ester, dibasic acid ester, phosphoric acid ester, etc.), various ethers (for example, Polyphenyl ether, etc.), as well as isomers of slack and GTL WAX.

 In the present invention, the mineral oil may be used singly or in combination of two or more as the base oil. One of the above synthetic oils may be used, or two or more may be used in combination. Further, one or more mineral oils and one or more synthetic oils may be used in combination.

[0015] The (A) polymetatalylate viscosity index improver in the hydraulic fluid composition of the present invention has a weight average molecular weight in the range of 10,000 to 50,000, and as such Can include, for example, polymetatalates and dispersed polymetatalates. If the weight average molecular weight is less than 10,000, the viscosity index improvement effect may not be sufficiently exhibited.If it exceeds 50,000, the polymer will be cut during use and the viscosity index improvement effect will not be exhibited! /, There is a case. Preferable! /, The weight average molecular weight is 20,000 to 40,000.

 The weight average molecular weight is a value in terms of polystyrene measured by gel permeation chromatography (GPC) method.

 In the present invention, when a dispersed polymetatalylate is used, there is no particular limitation, but for example, a force S can be cited to list a copolymer of metatalylate and a nitrogen-containing monomer having an ethylenically unsaturated bond. .

 Examples of the nitrogen-containing monomer having an ethylenically unsaturated bond include dimethylaminomethyl methacrylate, jetylaminomethyl methacrylate, dimethylaminoethyl methacrylate, jetylaminoethyl methacrylate, 2-methyl-5 —Burpyridine, morpholinomethyl metatalylate, morpholinoethyl metatalylate, N-bulylpyrrolidone, and mixtures thereof.

 [0016] The copolymerization ratio of the metatalylate and the nitrogen-containing monomer having an ethylenically unsaturated bond is preferably 80: 20-95: 5 by mass ratio! /.

In the hydraulic fluid composition of the present invention, the component (A) polymetatalylate viscosity index improver may be used alone or in combination of two or more. The blending amount is selected in the range of !! to 20% by mass based on the total amount of the composition. The formulation When the amount is less than 1% by mass, the effect of improving the viscosity index is not sufficiently exerted. On the other hand, when the amount exceeds 20% by mass, no improvement in the effect is recognized for the amount.

 The amount of component (A) is preferably 1 to 15% by mass, more preferably 2 to 10% by mass.

 [0017] The acid amide compound (B) in the hydraulic fluid composition of the present invention is preferably a condensation reaction product of a fatty acid and a polyalkylene polyamine. For example, a fatty acid having 8 to 24 carbon atoms. Acid and the following general formula (I)

 H N (CH CH NH) H (I)

 (In the formula, n represents a number having an average value of 2 to 6.)

 The condensation reaction product with the polyethylene polyamine represented by these is mentioned.

 [0018] The fatty acids having 8 to 24 carbon atoms include linear or branched saturated and unsaturated fatty acids, for example, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, hexadecane. Acid, octadecanoic acid (stearic acid), hydroxyoctadecanoic acid, icosanoic acid, helicosanoic acid, docosanoic acid, tricosanoic acid, tetracosanoic acid, otathenic acid, decenoic acid, dodecenoic acid, tetradecenoic acid, hexadecenoic acid, octadecenoic acid (Oleic acid), linear saturated and unsaturated fatty acids such as nonadecenoic acid, icosenoic acid, hencosenoic acid, docosenoic acid, tricosenoic acid and tetracosenoic acid, and branched fatty acids corresponding thereto.

 Among these, isostearic acid which is a branched fatty acid having a total carbon number of 18 is preferable.

On the other hand, specific examples of the polyethylene polyamine represented by the general formula (I) include, for example, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexaethyleneheptamine. Etc.

[0020] The acid amide compound (B) used in the hydraulic fluid composition of the present invention is preferably a reaction product using the above fatty acid and polyalkylene polyamine as reaction raw materials. This reaction product may be a condensation reaction of a fatty acid and a polyalkylene polyamine by a known method. For example, the reaction is performed at a reaction temperature of 100 to 150 ° C. and a reaction time of 1 to 5 hours. In this case, it is preferable that the ratio of the fatty acid and the polyalkylene polyamine, which is a raw material for the reaction, is a slight excess of an arbitrary force. In the present invention, these acid amide compounds as the component (B) may be used alone or in combination of two or more. The blending amount of the component (B) is in the range of 0.005 to 5% by mass, preferably 0.0;! To 5% by mass based on the total amount of the composition. / ₀ , more preferably 0.02 to 3% by mass.

 In the hydraulic fluid composition of the present invention, among the components (C), the acidic phosphate ester compound (c 1) is represented by the general formula (式 -1)

[0022] [Chemical 4]

[0023] A compound represented by:

In the general formula (Π-1), R ¹ is a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ² is a hydrocarbon group having 1 to 18 carbon atoms. The hydrocarbon group having 1 to 18 carbon atoms includes an alkyl group having 1 to 18 carbon atoms, an alkyl group having 2 to carbon atoms, an alkenyl group having 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, and 7 to 7 carbon atoms. And 18 aralkyl groups. Examples of the alkyl group and alkenyl group may be linear, branched, or cyclic. Examples thereof include a methylol group, an ethyl group, an n propyl group, an isopropyl group, an n butyl group, an isobutyl group, s ec butyl group, tert butyl group, various pentyl groups, various hexyl groups, various octynole groups, various decyl groups, various dodecyl groups, various tetradecyl groups, various hexadecyl groups, various octadecyl groups, cyclopentyl group, cyclohexyl Group, aryl group, propenyl group, various butur groups, various hexenyl groups, various octatur groups, various decenyl groups, various dodecenyl groups, various tetradecenyl groups, various hexadecenyl groups, various octadecenyl groups, cyclopentyl groups, Examples include a cyclohexenyl group.

 Examples of the aryl group having 6 to 18 carbon atoms include phenyl group, tolyl group, xylyl group, and naphthyl group, and examples of the aralkyl group having 7 to 18 carbon atoms include benzyl group, phenethyl group, Examples thereof include naphthylmethyl group, methylbenzyl group, methylphenethyl group, and methylnaphthylmethyl group.

The total carbon number of R ¹ and R ² is preferably in the range of 3 to 36. Therefore, R ¹ and R ² are It is preferable to select an appropriate group so that the total number of carbon atoms is in the range of 3 to 36.

[0024] The acidic phosphate compound of the general formula (式 -1) is an acidic phosphate monoester or an acidic phosphate diester.

 Examples of acidic phosphoric acid mono- and diesters include mono (di) n propyl acid phosphate, mono (di) n butyl acid phosphate, mono (di) -2-ethylhexyla

And mono (di) palmityl acid phosphate, mono (di) stearyl acid phosphate, mono (di) oleyl acid phosphate, and the like.

[0025] Among the components (C), the acidic phosphite compound of (c 2) has the general formula (Π-2)

[0026] [Chemical 5]

R ³ ― 0

 NO-P-OH "-(11-2)

It is a compound represented by R ⁴ — 0.

R ³ in the general formula (Π—2) is the same as R ¹ in the general formula (Π— 1), and R ⁴ in the general formula (II 2) is the same as R ² in the general formula (Π— 1). It is. In addition, the total carbon number of R ³ and R ⁴ is the same as that of the acidic phosphate compound in the general formula (式 -1).

 Examples of the acidic phosphite compound of the general formula (Π-2) include mono (di) 2-ethylhexyl hydrogen phosphite, mono (di) decyl hydrogen phosphite, mono (di) dodecyl. Hydrogen phosphite (mono (di) lauryl hydrogen phosphate), mono (di) -octadecyl hydrogen phosphite (mono (di) -stearyl hydrogen phosphite), mono (di) 9-octadece Nil hydrogen phosphite (mono (di) 1-year-old reino renoid rhodium phosphite), mono (di) phenol rehydrogen phosphite, and the like.

[0027] In the present invention, as the component (C), the acidic phosphoric acid ester compound (c-1) may be used alone or in combination of two or more. In addition, the acid (c 2) 1 type of phosphite compound may be used, or 2 or more types may be used in combination! In addition, one or more acidic phosphoric acid ester compounds of (c 1) and one or more acidic phosphorous acid ester compounds of (c 2) may be used in combination! /. The blending amount of the component (C) is 0.005 to 5% by mass, preferably 0.0;! To 3% by mass, more preferably 0.02 to 2% by mass, based on the total amount of the composition. It is. Further, in relation to the blending amount of the component (B), it is preferable to blend so that the mass specific force of (B) / (C) is 0.;! ~ 4.0. · It is more preferable to blend so that it becomes zero. If the mass ratio of (B) / (C) is 0 .;! ~ 4.0, there is an effect of preventing chattering (stick-slip) phenomenon between rubber and resin (resin).

[0028] In the hydraulic fluid composition of the present invention, at least one selected from polyhydric alcohol partial esters, alkanolamines, olefins, and dithiocarbamate compounds as the lubricity improver of component (D). A seed is used.

 In the polyhydric alcohol partial ester of component (D), the polyhydric alcohol used as a raw material is not particularly limited, but aliphatic polyols are preferred, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene. Dihydric alcohols such as glyconole, trimethylene glycol, tetramethylene glycol, neopentyl glycol, trihydric alcohols such as glycerin, trimethylolethane, trimethylolpropane, diglycerin, triglycerin, pentaurisritorone, dipentaerythritol Examples include tetrahydric or higher polyhydric alcohols such as Nore, Mannit, and Sorbit.

 The number of ester bonds in the partial ester is not particularly limited as long as at least one hydroxyl group remains. The hydrocarbyl group constituting the ester bond is preferably an alkyl group or alkenyl group having 6 to 20 carbon atoms, such as various hexyl groups, octyl groups, decyl groups, dodecyl groups, tetradecyl groups, hexadecyl groups, Examples thereof include an otadecyl group, a hexenyl group, an otatur group, a decenyl group, a dodecenyl group, a tetradecenyl group, a hexadecenyl group, and an octadecenyl group.

[0029] Specific examples of the partial ester of the polyhydric alcohol include neopentyl glycol monolaurate, neopentinoreglycolole monomyristate, neopentinoreglycolenoremonono noremitate, neopentinoreglycolole monostearate, neopenty Noreglycol noremonoi stearate, trimethylolpropane mono or dilaurate, trimethylolpropane Non- or dimyristate, trimethylolpropane mono or dipalmitate, trimethylol propane pan mono or distearate, trimethylolpropane mono or diisostearate, glycerin mono or dilaurate, glycerin mono or distearate, glycerin mono or diisostearate, etc. The power S can be, but is not limited to these. The (D) component polyhydric alcohol partial ester may be used singly or in combination of two or more.

[0030] Examples of the olefin fin as the lubricity improver of the component (D) include, for example, the general formula (III)

R ⁵ — S— R ⁶ (III)

(In the formula, R ⁵ represents an alkenyl group having 3 to 20 carbon atoms, R ⁶ represents an alkyl group or alkenyl group having 3 to 20 carbon atoms, and a represents an integer of !! to 8)

 The compound represented by these can be mentioned. This compound is obtained by reacting olefins having 3 to 20 carbon atoms or dimers or tetramers thereof with a sulfurizing agent such as sulfur or sulfur chloride, and propylene, isobutene, diisobutene or the like is preferable as the olefin. In the present invention, the (D) component olefin sulfide may be used alone or in combination of two or more! /.

[0031] Examples of the alkanolamine in the lubricity improver of the component (D) include stearinole monoethanolamine, decyl monoethanolamine, hexyl monopropanolamine, benzyl monoethanolamine, Phenyl monoethanolamine, tolyl monopropanolamine, dioleyl monoethanolamine, dilauryl monopropanolamine, dioctyl monoethanolamine, dihexyl monopropanolamine, dibutinore monopropanolamine, oleyl Diethanolamine, stearyl dipropanolamine, lauryl diethanolamine, octyl dipropanolamine, butyl ethanolamine, benzyl diethanolamine, phenyl diethanolamine, tolyl dipropanolamine Emissions, xylyl 'diethanol § Min, it may be mentioned triethanolamine Tano Honoré amines, disubstituted amines, and trisubstituted amines having a carbon number of 4-60 such as tripropanolamine Amin. These alkanolamines may be used alone or in combination of two or more.

[0032] As the Tiocarno Vite compound in the lubricity improver of the component (D), Preferred examples thereof include mite and methylene bistridecyl dithiocarnoite. These tiocarnoite compounds may be used alone or in combination of two or more.

[0033] In the hydraulic fluid composition of the present invention, a polyhydric alcohol partial ester, an alkanolamine, an olefin sulfide, and a thiocarnoite compound may be used as the lubricity improver of the component (D). Alternatively, two or more kinds may be used in appropriate combination. Further, the blending amount of the component (D) is selected in the range of 0.005 to 5% by mass based on the total amount of the composition. If the blending amount is less than 0.005% by mass, the friction at the sliding part of the hydraulic pump is reduced, the friction between the rubber material and the metal in the actuator installed in the hydraulic system is reduced, and the wear resistance is improved. Such effects are difficult to fully demonstrate. On the other hand, if it exceeds 5% by mass, sludge is generated more often, and water separability deteriorates. The (D) preferred amount of lubricant propensity above as the component is 0.0;! ~ 5 mass _^0/0, more preferably 0.03 to 3 mass _^0/0, more preferably 0.05 to 2 mass ⁰ / ₀ .

 [0034] In the hydraulic fluid composition of the present invention, if necessary, (E) at least 1 selected from an amine salt of an acidic phosphate ester and a phosphate triester compound as a lubricity improver. Seeds can be blended. Thereby, the effect of the lubricity improver may be further enhanced.

 [0035] As the amine salt of the acidic phosphate ester, the amine salt of the acidic phosphate ester represented by the general formula (用 い る -1) can be used. As the amine compound constituting the amine salt, mono-substituted amine, di-substituted amine and tri-substituted amine having 4 to 60 carbon atoms can be used.

Examples of mono-substituted amines include butylamine, pentylamine, hexylamine, cyclohexylamine, octylamine, laurylamine, stearylamine, oleylamine, benzylamine, and examples of disubstituted amines include dibutylamine, dipentylamine. , Dihexylamine, dicyclohexylamine, dioctylamine, dilaurylamine, distearylamine, dioleylamine, dibenzylamine and the like. Examples of tri-substituted amines are tributylamine, tripentylamine, trihexylamine. Examples include luamine, tricyclohexylamine, trioctylamine, trilaurinoleamine, tristearylamine, trioleylamine, and tribenzylamine. In addition alkanolamines such as stearyl 'monoethanolamine, decyl monoethanolamine, hexyl' monopropanolamine, benzyl 'monoethanolamine, phenyl' monoethanolamine, tolyl 'monopropanolamine, dioleyl' Monoethanolamine, dilauryl 'monopropanolamine, dioctyl' monoethanolamine, dihexyl 'monopropanolamine, dibutyl' monopropanolamine, oleyl * diethanolamine, stearyl 'dipropanolamine, lauryl' Diethanolamine, Octyl'dipropanolamine, Butyl'diethanolamine, Benzyl'diethanolamine, Phenylol-diethanolamine, Tolyl'Dipropanolamine, Xylyl'diethanolamine, Tri Tanoruamin, and the like tripropanolamine § Min.

 These amin compounds may be used alone or in combination of two or more.

 [0036] Examples of the phosphoric triester compound include those represented by the general formula (IV):

[0037] [Chemical 6]

[0038] [wherein, R ⁷ to R ⁹ are the same as R ² in the general formula ([pi). ]

A compound represented by the formula: triaryl phosphate, trialkyl phosphate, trianolalkyl phosphate, triaryl alkyl phosphate, trialkenyl phosphate, etc., for example, triphenyl phosphate, tricresyl phosphate, benzino Resifeninorephosphate, ethinoresifenenorephosphate, tributinorephosphate, ethinoresibutinorephosphate, cresinoresifeninorephosphate, dicresinorefeninophosphate, ethylphenyldiphenyl phosphate, di (ethylphenyl) ) Phenyl phosphate, propino leveno resifen eno ole phosphate, di (prop ino phenino ole) pheneno phosphite, trietino refeno enophosphate, tri Propinorefeninorephosphate, Butinolefeninoresifeninorephosphate, Di (butinolefeninore) feninorephosphate, Tribinore Pheninorephosphate, trihexinorephosphate, tri (2-ethinorehexinole) phosphide 卜, 卜 ridino lesenophosphine 卜, 卜 ラ ク リ 卜 卜 ミ リExamples include normytyl phosphate, tristearyl phosphate, and trioleyl phosphate.

[0039] As the lubricity improver of (E) that can be blended as necessary in the present invention, one or more of the amine salts of acidic phosphates may be used, or two or more of them may be used in combination. Good. Further, one kind of the above phosphoric acid triester compound may be used, or two or more kinds may be used in combination. Furthermore, one or more amine salts of acidic phosphate esters and one or more phosphate ester compounds may be used in combination. The amount of the component (E) is usually selected in the range of 0.005 to 5 wt% of the total amount of the composition, more preferably, 0.0;! ~ 5 mass _^0/0, more preferably, from 0.02 to 2 mass ^_0/0.

 [0040] In the hydraulic fluid of the present invention, a cleaning dispersant may be further blended as necessary.

 As the detergent / dispersant, an ashless detergent / dispersant and / or a metal detergent can be used.

 Here, examples of the ashless detergent dispersant include succinimides, boron-containing succinic acid imides, benzylamines, and boron-containing benzylamines.

 Examples of metal detergents include neutral, basic or overbased metal sulfonates, metal phenates, metal salicylates, metal phosphonates, and the like. These ashless detergents and metallic detergents may be used singly or in combination of two or more. The detergent-dispersant is usually about 0.01 to about!% By mass based on the total amount of the composition.

[0041] The hydraulic fluid composition of the present invention includes an antioxidant, a fungicide, a metal deactivator, a pour point depressant, an antifoam, as desired, as long as the object of the present invention is not impaired. It is possible to combine agents and demulsifiers.

 As an antioxidant, phenolic antioxidants and amine amines are preferably used.

The phenolic antioxidant is not particularly limited, and any of the known phenolic antioxidants conventionally used as antioxidants for lubricating oils may be appropriately selected. It can be selected and used. Examples of the phenolic antioxidants include 2,6 ditertbutyl-4-methylphenol; 2,6 ditertbutyl-4-ethylphenol; 2,4,6 tritertbutylbutylphenol; 2,6ditertbutyl-4-hydroxymethyl 2, 6 Di tert butyl phenol; 2, 4 Di tert 6- tert butyl phenol; 2, 6 Di tert butyl -4-phenol (N, N dimethylaminomethyl) phenol; 2, 6 Di tert amino le 4 Methyl phenol; n Octadecyl 3 1 (4-hydroxy-1,3,5-di-tert-butylphenyl) monocyclic phenols such as propionate, 4, 4, -methylenebis (2,6-ditert-butylphenol); 4, 4, 1-isopyridenebis (2 , 6 Di-tert-butylphenol); 2, 2, 1-methylenebis (4 methylolene 6-tert-butylphenol); 4, 4'-bis (2, 6 1 tert butyl phenol); 4, 4 'bis (2 methyl-6- tert butyl phenol); 2, 2, methylene bis (4-ethyl 6- tert butyl phenol); 4, 4, butylidene bis (3-methyl-6- tert butyl phenol) ); 2, 2, thiobis (4-methyl-6-tert butylphenol); 4,4'-thiobis (3-methyl-6-tert butylphenol) and the like. Among these, monocyclic phenols are preferable from the viewpoint of effects.

Yes

As the amine-based antioxidant, there is no particular limitation, and it is possible to appropriately select and use any known amine-based antioxidant conventionally used as an antioxidant for lubricating oils. Examples of the amine-based antioxidant include diphenylamine-based compounds, specifically diphenylamine and monooctyldiphenylamine; monononyldiphenylamine; 4, 4 ′ dibutyldiphenylamine; 'Dihexyldiphenylamine; 4, 4'Dioctyldiphenylamine;4,4'-Dinonyldiphenylamine;Tetrabutyldiphenylamine;Tetrahexyldiphenylamine; Tetraoctyl Diphenylamine: an alkylated diphenylamine having an alkyl group having 3 to 20 carbon atoms such as tetranonyldiphenylamine and the like, and naphthylamine-type compounds such as α-naphthylamine; phenyl a naphthylamine, and butylphenol Nilu α naphthylamine; hexyl fe Nilu α naphthylamine; Amin; Noyurufeniru a Nafuchiruamin alkyl substituted phenylene Lou α Nafuchinore having 3 to 20 carbon atoms, such as Amamine etc. are mentioned. Of these, diphenylamines are better than naphthylamines

From the viewpoint of 1S effect, an alkylated diphenylenoamine having an alkyl group having 3 to 20 carbon atoms, particularly 4,4′-di (C to C alkyl) diphenylamine, is particularly preferable.

 3 20

 [0043] In the present invention, the phenolic antioxidant may be used singly or in combination of two or more. In addition, one kind of the amine antioxidant may be used, or two or more kinds may be used in combination. Further, one or more phenolic antioxidants and one or more amine antioxidants may be used in combination.

 In the present invention, the blending amount of the antioxidant is usually from 0.05 to 2.0% by mass, preferably from 0. to ~, based on the total amount of the composition, from the viewpoint of oxidation stability and other physical properties. 1% by mass.

 [0044] Examples of the antifungal agent include metal sulfonates and succinates.

 The blending amount of these antifungal agents is usually about 0.0 ;! to 5% by mass, preferably 0.03 to;% by mass, based on the total amount of the composition from the viewpoints of blending effects and other physical properties. It is.

 Examples of the metal deactivator include benzotriazole and thiadiazole. The preferred compounding amount of these metal deactivators is usually about 0.005 to 1% by mass, preferably 0.007 to 0.5%, based on the total amount of the composition, from the viewpoint of the blending effect and other physical properties. % By mass.

 As a pour point depressant, it is possible to use polymetatalylate having a weight average molecular weight of about 50,000 to 150,000. From the viewpoints of blending effect and other physical properties, the blending amount of the pour point depressant is usually from 0.;! To 5 mass%, preferably from 0.2 to 2 mass%, based on the total amount of the composition.

[0045] As the antifoaming agent, the antifoaming property is effectively exhibited by adding this polymeric silicone antifoaming agent, which is preferably a polymeric silicone antifoaming agent.

 Examples of the high molecular silicone antifoaming agent include organopolysiloxane, and fluorine-containing organopolysiloxane such as trifluoropropylmethyl silicone oil is particularly preferable. This high molecular weight silicone-based antifoaming agent is preferably added in an amount of about 0.0001 to 0.5% by mass based on the total amount of the composition from the viewpoint of the defoaming effect and economical efficiency. It is more preferable to add 3% by mass.

Examples of the demulsifier include conventionally known ones such as a sulfate ester salt of castor oil and petroleum sulfate. Anionic surfactants such as phonates, cationic surfactants such as quaternary ammonium salts and imidazoline types, and condensation products of ethylene oxide and propylene oxide. And specific examples thereof include polyoxyalkylene polyglycol and its dicarboxylic acid ester, and an alkylene oxide adduct of an alkylphenol-formaldehyde polycondensate.

 [0046] As described above, the present invention includes a specific base oil, the components (A) to (D), and these components.

 (E) A hydraulic fluid composition comprising a component, usually a specific base oil, components (A) to (D), and a hydraulic fluid composition containing these components and component (E) is there.

 [0047] The hydraulic fluid composition of the present invention has good energy saving and thermal stability (sludge resistance).

Has wear resistance, anti-scuffing resistance, water separation, and sliding friction reduction

. Therefore, it is preferably used as a hydraulic fluid for use in hydraulic equipment such as injection molding machines, machine tools, construction machinery, and steelmaking facilities, but for other hydraulic equipment such as industrial robots and hydraulic equipment such as hydraulic elevators. Good performance as an oil. Example

 [0048] Next, the present invention will be described in more detail with reference to examples. The present invention is not limited to these examples.

 Various characteristics were determined according to the following methods.

 (1) Base oil properties

 'Sulfur content: Measured according to JIS K 2541.

 • Saturation: Measured according to ASTM D 2007.

 • Absolute viscosity at 40 ° C: Calculated from 40 ° C kinematic viscosity and density measured according to JIS K 2283.

 • Viscosity index: Measured according to JIS K 2283.

[0049] (2) Performance of hydraulic fluid composition

 (I) High-pressure vane pump test

Construct hydraulic circuit using "TOKIMEC SQP2-12" as a vane pump, operate at oil temperature 60 ° C, rotation speed: 1200rpm, pressure: 17.5MPa, consumption during steady operation Measure power (kW) and mechanical efficiency. (Mouth) Thermal stability test

 In accordance with the “Lubricant Thermal Stability Method” specified in JIS K 2540, after conducting a thermal stability test for 7 days in a 150 ° C air thermostat, the sample oil after the test is filtered through a filter, Measure the amount of sludge.

(C) Seizure resistance by FZG gear test

 ASTM D 5182—91 ί compliant, 90. The test is displayed at 15 ° C, 15 minutes at C, and at the stage where the rolling load is generated.

(2) Water separation

 In accordance with JIS 2525, conduct a water separability test at a temperature of 54 ° C, and measure the time required to reach an emulsified layer strength of ¾ mL [demulsibility] (min).

(E) Friction coefficient

 Using a powdered reciprocating friction tester, measure the friction coefficient under the following conditions. Oil: 2 o C

 Load: 19. 6N

 Sliding distance: 40mm

 Sliding speed: 60mm / min

 Number of slides: 5 round trips

 Friction material: Upper rubber material (U 801, manufactured by NOK)

 Lower chrome plated steel plate (50 × 100 × 1 mm, manufactured by Test Piece Co., Ltd.) The types of each component used for preparing the hydraulic fluid composition are as follows.

 (1) Base oil-1: Paraffinic hydrotreated mineral oil corresponding to API classification Group III, sulfur content 0.01 mass% or less, saturation content 99 mass%, viscosity index 121, absolute viscosity at 40 ° C 29.2 ImPa 's

 (2) Base oil 2: Hydrotreated paraffinic mineral oil, sulfur content of 0.01 mass% or less, saturated content of 98 mass%, viscosity index of 118, absolute viscosity at 40 ° C 34 · 96mPa-s

 (3) Viscosity index improver: Polymetatalylate with a weight average molecular weight of 37,000

 (4) Acid amide compound: Condensate of isostearic acid and tetraethylenepentamine

(5) Acid phosphate ester 1: oleyl acid phosphate (6) Acid phosphate ester 2: Di (2 ethylhexyl) phosphate

 (7) Acid phosphite 1: oleyl hydrogen phosphite

 (8) Alkanolamine: N alkyldiethanolamine

 (9) Fatty acid glyceride: oleic acid glyceride (mono-form 60 mass%, di-form 20 mass%, tri-form 20 mass%)

 (10) Olefin sulfide: Butene sulfide

 (11) Chiokaba Mate: Methylenebis (Dibutino Resizi talent-Bamate)

 (12) Acid phosphate ester amine salt: Mono (di) methyl acid phosphate dodecylamine salt

 (13) Phosphate triester: tricresyl phosphate

 (14) Antioxidants: 2, 6 G tert butyl -4-methylphenol

 (15) Antifungal agent: Alkenyl succinic acid polyhydric alcohol ester

 (16) Metal deactivator: Benzotriazole deactivator

 (17) Demulsifier: Polyoxyethylene polyoxypropylene glycol

 (18) Antifoaming agent: Polymetatalylate antifoaming agent

[0051] Examples;! To 4 and Comparative Example 1

 Each hydraulic fluid composition having the composition shown in Table 1 was prepared, and the performance of each was evaluated. The results are shown in Table 1.

 In Comparative Example 1, a Zn-based commercial oil (hydraulic hydraulic oil) having a viscosity index of 108 was used.

[0052] [Table 1]

Table 1

[0053] From Table 1, it can be seen that:

 As a result of the high-pressure vane pump test, Examples 1 to 4 are both excellent in power consumption and mechanical efficiency. As a result of the FZG test, Examples 1 to 4 all satisfy ISO standard 10 stages or more. As a result of thermal stability, in Examples 1 to 4, the amount of sludge deposited is much smaller than that of the Zn-based commercial oil in Comparative Example 1. As a result of the water separability test, it was confirmed that Examples 1 to 4 could maintain good water separability. As a result of the pound test, all of Examples 1 to 4 were able to reduce the friction coefficient with respect to the rubber material.

 Industrial applicability

[0054] The hydraulic fluid composition of the present invention has good energy saving, thermal stability (sludge resistance), wear resistance, seizure resistance (scuffing resistance), water separation, and friction reduction of sliding parts. Suitable for the hydraulic machinery field, machine tool field, industrial machinery field, etc.

Claims

The scope of the claims  [1] Sulfur content of less than 0.03 mass%, saturation content of 90 mass% or more, viscosity index of 80 or more, and absolute viscosity at 40 ° C 1 to; a base oil having the property of lOOOOmPa's;  (A) 1 to 20% by mass of a polymetatalylate viscosity index improver having a weight average molecular weight of 10,000 to 50,000  (B) acid amide compound 0.005-5 mass%  (C) (c 1) General formula (II 1) [Chemical 1

(In the formula, R ¹ represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ² represents a hydrocarbon group having 1 to 18 carbon atoms.)  An acidic phosphate compound represented by the formula: and / or (c 2) the general formula (式 — 2) [Chemical 2]

(In the formula, R ³ represents a hydrogen atom or a hydrocarbon group having 1 to 18 carbon atoms, and R ⁴ represents a hydrocarbon group having 1 to 18 carbon atoms.)  An acidic phosphite compound represented by the formula 0.005 to 5% by mass  (D) A hydraulic fluid composition comprising 0.005 to 5% by mass of at least one selected from a polyhydric alcohol ester, an alkanolamine, an olefin sulfide and a thiocarbamate compound.  [2] Furthermore, (E) an amine salt of an acidic phosphate compound and a general formula (IV) [Chemical 3]

(Wherein R ^{7 to} R ⁹ each independently represents a hydrocarbon group having 1 to 18 carbon atoms.) At least one selected from the phosphoric triester compounds represented by: The hydraulic fluid composition according to claim 1, which is formulated.