JPH0113520B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel water-formed hydraulic fluid. More specifically, the present invention relates to an emulsion type water-molded hydraulic fluid containing mineral oil or the like as a lubricating component. Flame-retardant hydraulic fluids conventionally used in hydraulic equipment in places where there is a risk of fire include phosphate ester, fatty acid ester, water-glycol, and emulsion oils. Among these, water-based hydraulic fluids are attracting the most attention due to their fire resistance.
New hydraulic fluids containing large amounts of water are being considered from the viewpoint of resource conservation and environmental conservation. In other words, conventional water-molded hydraulic fluids, with the exception of some solution-type hydraulic fluids, have a water content of around 40%, but high water content hydraulic fluids (HWBF) with a water content of 80% or more A search is being made. There are two types of high-water content hydraulic fluids: solution type and emulsion type, but in both cases, because of the high water content, there are problems with liquid stability, foaming properties, rust prevention, etc. Become. For example, in the case of an emulsion-type hydraulic fluid, there is a method of emulsifying water-insoluble lubricant components such as mineral oil with an emulsifier, as in the case of conventional emulsion-type hydraulic fluids, but if a large amount of water is present, it is extremely difficult to keep the fluid stable. It is difficult and tends to cause liquid separation, and when the liquid separates, it rapidly loses lubricity and causes filter clogging. Furthermore, since a surfactant is used as an emulsifier, bubbles are likely to form, causing cavitation. In order to suppress this foaming property, various antifoaming agents have been studied, but in reality, there are almost no antifoaming agents that maintain their effectiveness. The inventors of the present invention have conducted various studies to improve the above drawbacks, and have found that an ether containing 1 to 10 moles of ethylene oxide (EO) of petroleum sulfonate and mono- and/or diglyceride, which uses mineral oil and fatty acid soap as lubricating ingredients, has been developed. By using an ester-type surfactant as an emulsifier, we have completed a water-molded hydraulic fluid that has excellent emulsion-type stability, lubricity, and rust prevention properties, and has low foaming properties. That is, the water-molded hydraulic fluid of the present invention contains 1 to 9% mineral oil.
(wt%, same below), petroleum sulfonate 0.1~
2%, 0.1-2% ether ester type surfactant which is 1-10 mole adduct of mono- and/or diglyceride ethylene oxide (EO), and 0.1-2% fatty acid soap. It is a working fluid. For ease of transportation, the water-formed hydraulic fluid of the present invention contains 50 to 90% mineral oil, 5 to 20% petroleum sulfonate, and 1 to 10 mole ethylene oxide (EO) adduct of mono- and/or diglyceride as a stock solution. It is preferable to prepare a composition containing 5 to 20% of a certain ether ester type surfactant, 5 to 20% of fatty acid soap, and 1 to 20% of water, and dilute it 10 to 50 times before use. This stock solution is self-emulsifying in water and is O/W.
Forms an emulsion, quickly emulsifies and disperses it, and provides a water-molded hydraulic fluid with excellent stability, lubricity and rust prevention, and low foaming properties. The mineral oil contained in the water-molded hydraulic fluid of the present invention functions as a lubricant component of the hydraulic fluid, and is contained in the hydraulic fluid at a rate of about 1 to 9%, and in the undiluted solution is preferably 50 to 90%, preferably 65 to 85%.
% contained. Preferred mineral oils include those commercially available as lubricating oils, and more preferably JIS spindle oil No. 1 or spindle oil No. 2. In the present invention, petroleum sulfonate contained in the water-molded hydraulic fluid mainly functions as an emulsifier for mineral oil, and also functions as a rust preventive agent. The ether ester type surfactant, which is an adduct of 1 to 10 moles of ethylene oxide (EO) to mono- and/or diglyceride, contained in the water-molded hydraulic fluid stock solution in the present invention mainly functions as an emulsifier for mineral oil. The ether ester type surfactant is an adduct of mono- and/or diglyceride with 1 to 10 moles of ethylene oxide (EO). The fatty acid soap contained in the water-molded hydraulic fluid stock solution of the present invention mainly functions as a lubricant component, as well as functions as an antifoaming agent, emulsifier, and rust preventive. The fatty acid is preferably a fatty acid having 14 to 18 carbon atoms, more preferably an unsaturated fatty acid having 16 to 18 carbon atoms. Also,
Examples of alkalis that neutralize fatty acids include alkali metals and amines, which are used alone or as mixed salts. The water contained in the water-forming hydraulic fluid stock solution in the present invention should preferably be 1 to 20% of the stock solution.Water gives fluidity and uniformity to the stock solution, and if the amount is outside this range, the stock solution may separate or become a paste. It becomes like this. Furthermore, if necessary, it also functions as a dissolved component of extreme pressure additives, PH adjusters, antioxidants, metal ion sequestering agents, and the like. It can be added at this stock solution stage. General amines and alkali metal hydroxides are used as PH adjusters, mercaptobenzothiazole, benzotriazole, etc. are used as antioxidants, and aminocarbons such as ethylenediaminetetraacetic acid are used as sequestering agents. Examples of extreme pressure agents include acids and metal salts thereof, and phosphorus compounds and sulfur compounds. When using the working fluid stock solution of the present invention diluted 10 to 50 times with water, the diluted working fluid is O/
W emulsion becomes a high water content emulsion type working fluid (HWBF) with lubricity, safety, and rust prevention properties, but in order to further improve these properties, thickeners, pour point depressants, PH regulators, antioxidants, sequestering agents, oiliness improvers, and extreme pressure additives can be added. Thickeners include polyoxyalkylene glycol compounds, pour point depressants include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, etc., and pH adjusters include amines,
Alkali metal hydroxides etc.; antioxidants such as mercaptobenzothiazole and benzotriazole; metal ion sequestrants such as aminocarboxylic acids and their metal salts such as ethylenediaminetetraacetic acid;
Oiliness improvers include carboxylic acid esters, alkali metal salts, amine salts, etc.; extreme pressure additives include phosphorus compounds, sulfur compounds, etc. As is clear from the above description, the water-formed hydraulic fluid obtained by diluting the water-formed hydraulic fluid stock solution is particularly useful for high water content hydraulic fluids (HWBF) containing a large amount of water. EXAMPLES Next, the present invention will be explained in more detail with reference to Examples, but the present invention should not be limited thereto. Preparation of water-molded hydraulic fluid stock solution A: 70 g of spindle oil No. 1 (Nisseki Products), 10 g of petroleum sulfonate (Sulhole #400, Matsumura Oil Products), ether ester type surfactant (addition of 4 moles of EO of a mixture of tallow monoglyceride and diglyceride) (per OH)
) 10g, sodium oleic acid soap 5
g, distilled water, 3 g, and 2 g of a rust preventive agent, metal ion sequestering agent, and antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as the water-molded hydraulic fluid stock solution A used in the present invention. B Spindle oil No. 2 (Nisseki products) 75g, petroleum sulfonate (Sulhole #400) 7g,
Ether ester type surfactant (mixture of tallow monoglyceride and diglyceride)
10 g of EO3 mole adduct (per OH), 5 g of oleic acid triethanolamine soap,
1 g of distilled water, 2 g of a rust preventive agent, a sequestering agent, and an antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is used as the working fluid stock solution B used in the present invention.C Spindle oil No. 2 60g, petroleum sulfonate (Sulhole #400) 5g, ether ester type surfactant (addition of 3 moles of EO of a mixture of beef tallow monoglyceride and diglyceride (per OH) 17 g of EO4 mole adduct (per OH) of a mixture of beef tallow monoglyceride and diglyceride (50%), 10 g of sodium triethanolamine salt of oleic acid (Na:TEOA=1:1), 6 g of distilled water,
2 g of a rust preventive agent, a sequestering agent, and an antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is the working fluid stock solution C used in the present invention. D. Spindle oil No. 2 75 g, petroleum sulfonate (sulfol #400) 10 g, oleic acid sodium salt 10 g, distilled water 3 g, rust preventive,
Mix 2g of metal ion sequestering agent and antioxidant compound to make 100g of brown liquid water-molded hydraulic fluid stock solution.
I got it. This is referred to as comparative water-forming hydraulic fluid stock solution D. E Spindle oil No. 2 75g, ether ester type surfactant (addition of 3 moles of EO of a mixture of beef tallow monoglyceride and diglyceride (OH
15 g of EO4 mole adduct (per OH) of a mixture of 50% beef tallow monoglyceride and diglyceride (50%), 10 g of triethanolamine salt of oleic acid, 3 g of distilled water,
2 g of a rust preventive agent, a sequestering agent, and an antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as comparative water-forming hydraulic fluid stock solution E. F Spindle oil No. 2 70g, petroleum sulfonate (Sulhole #400) 15g, ether ester type surfactant (EO4 mole adduct (per OH) of a mixture of tallow monoglyceride and diglyceride) 10g, distilled water 3g, rust inhibitor, metal Ion sequestering agent, antioxidant mixture 2
Mix g to obtain a brown liquid water-forming hydraulic fluid stock solution.
Obtained 100g. Compare this with water molding operation stock F
shall be. G Spindle oil No. 1 70g, petroleum sulfonate (Sulhole #400) 10g, ether ester type surfactant of 2 mole adduct of coconut oil monoglyceride EO 10g, sodium oleic acid soap 5g, distilled water 3g, rust inhibitor, metal ion sequestration and 2 g of the antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as the hydraulic fluid G used in the present invention. H Spindle oil No. 1 70g, petroleum sulfonate (Sulfol #400) 10g, ether ester type surfactant of 3 mole adduct of coconut oil diglyceride EO 10g, sodium oleic acid soap 5g, distilled water 3g, rust inhibitor, metal ion sequestration and 2 g of the antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as the hydraulic fluid H used in the present invention. I Spindle oil No. 1 70g, petroleum sulfonate (sulfol #400) 10g, ether ester type surfactant of 12 mole tallow monoglyceride EO adduct 10g, sodium oleic acid soap 5g, distilled water 3g, rust preventive, sequestering agent , and 2 g of the antioxidant mixture were mixed to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as comparative water-forming hydraulic fluid stock solution I. J Spindle oil No. 1 70g, petroleum sulfonate (sulfol #400) 10g, tallow monoglyceride (without EO addition) surfactant 10
g, 5 g of sodium oleic acid soap, 3 g of distilled water, and 2 g of a rust preventive agent, sequestering agent, and antioxidant mixture to obtain 100 g of a brown liquid water-forming hydraulic fluid stock solution. This is referred to as comparative water-forming hydraulic fluid stock solution J. Evaluation of physical properties of water-formed hydraulic fluid stock solutions (1) A safety test was conducted on the water-formed hydraulic fluid stock solutions A to C used in the present invention prepared in (1) and the comparative water-formed hydraulic fluid stock solutions D to F. Table the results.
Shown in 1.

[Table] As is clear from Table 1, the working fluid stock solutions A to C according to the present invention are superior in stability under each condition compared to the comparative working fluid stock solutions D to F. Evaluation of physical properties of water-formed hydraulic fluid stock solutions (2) The physical properties of each of the 5% aqueous solutions of water-formed hydraulic fluid stock solutions A to C according to the present invention and comparative water-formed hydraulic fluids D to F prepared in step (2) were evaluated. The results are shown in Table-2. Stability was determined by standing at room temperature and 50°C for one month and observing the state of liquid separation. The foaming property is
Pour 25ml of the aqueous solution into a 100ml graduated cylinder,
The mixture was shaken vigorously by hand up and down 50 times, and after being left to stand, the volume of foam was measured. In Table 2, the foam capacity of 90ml or more indicates that the foam has reached the top of the cylinder. The friction coefficient was measured using a pendulum tester. Rust prevention tests are performed on steel plates, aluminum plates, and copper plates.
The number of days until rusting was investigated in a 50℃ constant temperature bath.

【table】

[Table] As is clear from Table 2, the 2% aqueous solutions A to C of the water-molded hydraulic fluid stock solution according to the present invention have lower foaming properties, oil lubricity, and lower oil lubricity than the 2% aqueous solutions D to F of the comparative water-molded hydraulic fluid stock solution. It can be seen that it is excellent in both stability and rust prevention. Performance evaluation of 2% aqueous solution of water-formed hydraulic fluid stock solution 2% aqueous solutions A to C of water-formed hydraulic fluid stock solution according to the present invention, 2% aqueous solutions D and E of water-formed hydraulic fluid stock solution according to the present invention, and oleic acid as a comparative sample. A 2% aqueous solution of triethanolamine salt was subjected to a wear resistance test using a Schell four-ball tester and a vane pump. Ciel 4 ball test
The test was carried out at 1500 rpm and 20 Kg/cm ² for 15 minutes, and the wear marks were measured. In addition, the vane pump test used a Bitkers Vane Pump V-105C, and the discharge pressure
50Kg/cm ² , shaft rotation speed 1200rpm, liquid temperature 40℃
The vehicle was operated for 50 hours and the amount of wear on the vane and cam ring was measured. The results are shown in Table-3.

【table】

[Table] As is clear from Table 3, the working fluid of the present invention
B and C have superior wear resistance compared to comparative hydraulic fluids D, E, and F.

Claims (1)

[Claims] 1 Ether ester type surfactant which is an ethylene oxide (EO) 1 to 10 mole adduct of mineral oil 1 to 9% (weight %, same below), petroleum sulfonate 0.1 to 2%, and mono- and/or diglyceride.
A water-molded hydraulic fluid containing 0.1-2% and 0.1-2% fatty acid soap.