Emulsifier composition and lubricant composition

Abstract

Provided is an emulsifier composition containing: (A) a polyoxyalkylene alkyl ether represented by formula (1); (B) one or more sorbitan mono-fatty acid esters selected from the group consisting of sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monooleate; and (C) one or more polyhydric alcohols selected from the group consisting of 1,2-alkanediols having 6-18 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6-8 carbon atoms. In formula (1), R1 represents an alkyl group having 10-18 carbon atoms, and the average values of n and m independently represent a number of 0-10. Provided that, at least one of n and m is not 0.

Description

Emulsifier composition and lubricant composition

[0001] The present invention relates to an emulsifier composition having emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions.

[0002] BACKGROUND ART In lubricating oils and fuel oils used in internal combustion engines, ships, aircraft, external combustion engines, etc., and processing oils and hydraulic oils used in metal processing and industrial machinery, etc., a technique of blending emulsifiers is used to exhibit emulsifying properties when mixed with water during use, and to prevent thickening when water is mixed in during use.

[0003] For example, Patent Document 1 describes a polymer compound made from the reaction of succinic acid or anhydride with a polyalkylene glycol, which can be used in a relatively small amount to achieve a stable emulsion over a wide temperature range and is suitable as an emulsifier for lubricating oil. Patent Document 2 describes a metalworking fluid concentrate containing a specific base oil containing decarboxylated rosin acid, a specific emulsifier, and optional additives as a metalworking fluid containing a bio-based lubricant with improved emulsion stability. Patent Document 3 describes a cold rolling oil composition containing a specific base oil and a nonionic surfactant, which can produce an emulsion with excellent emulsion stability and lubricity without being affected by temperature changes in the emulsion, even under harsh conditions where large amounts of wear powder are generated and mixed in.

[0004] Furthermore, Patent Document 4 describes a low-temperature stable lubricant composition containing a base oil of lubricating viscosity, a specific polymeric surfactant, and water and / or fuel contaminants as a polymeric surfactant and lubricant containing such surfactant to provide improved emulsion and flow properties at low temperatures. Patent Document 5 also discloses a naphtha-free emulsifier containing a specific fatty acid diethanolamide, a fatty acid, and an alcohol ethoxylate as a composition suitable for use as an emulsifier or scavenger to provide a stable nanoemulsion and at the same time provide a diesel fuel composition with good lubricity. Patent Document 6 also describes a method for powering a diesel engine with a fuel emulsifier, comprising a step of preparing the fuel emulsifier by emulsifying fuel and water in the presence of an emulsifier package containing a specific branched surfactant.

[0005] Japanese Patent Application Laid-Open No. 2019-122954 Japanese Patent Application Laid-Open No. 2022-098481 Japanese Patent Application Laid-Open No. 2021-038277 Japanese Patent Application Laid-Open No. 2022-032914 Special Publication No. 2022-524017 Special Publication No. 2023-547501

[0006] However, these techniques have the problem that it is difficult to form and maintain stable emulsions under various formulation conditions and circumstances. Specifically, it is not possible to easily form and maintain both stable oil-in-water emulsions and stable water-in-oil emulsions at room temperature, and there is a problem that the use environment, etc. is limited.

[0007] Therefore, an object of the present invention is to provide an emulsifier composition having emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions.

[0008] The present inventors conducted extensive research to solve the above-mentioned problems and discovered that an emulsifier composition containing three specific components has the emulsifying power to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, thereby completing the present invention. That is, the present invention relates to an emulsifier composition containing a polyoxyalkylene alkyl ether (A) represented by the following general formula (1), one or more sorbitan monofatty acid esters (B) selected from the group consisting of sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monooleate, and one or more polyhydric alcohols (C) selected from the group consisting of 1,2-alkanediols having 6 to 18 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms:

[0009]

[0010] (In the formula, R 1 represents an alkyl group having 10 to 18 carbon atoms, and the average values ​​of n and m each independently represent a number from 0 to 10. However, at least one of n and m is not 0. The arrangement of each structural unit may be in a block form or a random form.

[0011] According to the present invention, it is possible to provide an emulsifier composition having emulsifying power that enables easy formation and maintenance of both stable oil-in-water emulsions and stable water-in-oil emulsions.

[0012] The polyoxyalkylene alkyl ether (A) used in the present invention is a polyoxyalkylene alkyl ether represented by the following general formula (1).

[0013]

[0014] In general formula (1), R 1represents an alkyl group having 10 to 18 carbon atoms. Examples of such groups include linear alkyl groups such as decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups, and branched alkyl groups such as isodecyl, isoundecyl, isododecyl, isotridecyl, isotetradecyl, isopentadecyl, isohexadecyl, isoheptadecyl, and isooctadecyl groups. Among these, from the viewpoint of providing an emulsifier composition with excellent emulsifying power capable of easily forming and maintaining both stable oil-in-water emulsions and water-in-oil emulsions, R 1 is preferably an alkyl group having 10 to 14 carbon atoms, more preferably a linear alkyl group having 10 to 14 carbon atoms, even more preferably a linear alkyl group having 12 to 14 carbon atoms, and particularly preferably a dodecyl group or a tetradecyl group.

[0015] In general formula (1), the average values ​​of n and m each independently represent a number from 0 to 10. However, at least one of n and m is not 0. Examples of such combinations of n and m include a case where n is 0 and the average value of m is 1 to 10, a case where n is 1 to 10 and m is 0, and a case where n is 1 to 10 and m is 1 to 10. In general formula (1), when neither n nor m is 0, the arrangement of the structural units (i.e., oxyethylene units and oxypropylene units) may be block or random. In the present invention, from the viewpoint of achieving excellent emulsifying power in the resulting emulsifier composition, which can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, it is preferred that the average value of n is 1 to 10 and the average value of m is 1 to 10, more preferably that the average value of n is 2 to 8 and the average value of m is 1 to 6, and even more preferably that the average value of n is 3 to 7 and the average value of m is 2 to 5. Furthermore, when the average value of n is 1 to 10, the value of n is not particularly limited as long as the average value is 1 to 10, and can be adjusted appropriately depending on the purpose; however, from the viewpoint of particularly excellent emulsifying power that enables the resulting emulsifier composition to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the value of n is preferably in the range of 1 to 15, more preferably 1 to 10. Furthermore, when the average value of m is 1 to 10, the value of m is not particularly limited as long as the average value is 1 to 10, and can be adjusted appropriately depending on the purpose; however, from the viewpoint of particularly excellent emulsifying power that enables the resulting emulsifier composition to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the value of m is preferably in the range of 1 to 15, more preferably 1 to 10. Furthermore, when the average value of n is 2 to 8, the value of n is not particularly limited as long as the average value is 2 to 8, and can be adjusted appropriately depending on the purpose. However, from the viewpoint of the obtained emulsifier composition having particularly excellent emulsifying power that enables it to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the value of n is preferably in the range of 1 to 10, and more preferably 2 to 8.Furthermore, when the average value of n is 3 to 7, the value of n is not particularly limited as long as the average value is 3 to 7, and can be adjusted appropriately depending on the purpose; however, from the viewpoint of particularly excellent emulsifying power that enables the resulting emulsifier composition to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the value of n is preferably in the range of 2 to 8, more preferably 3 to 7. Furthermore, when the average value of m is 1 to 6, the value of m is not particularly limited as long as the average value is 1 to 6, and can be adjusted appropriately depending on the purpose; however, from the viewpoint of particularly excellent emulsifying power that enables the resulting emulsifier composition to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the value of m is preferably in the range of 0 to 7, more preferably 1 to 6. Furthermore, when the average value of m is 2 to 5, the value of m is not particularly limited as long as the average value is 2 to 5, and can be adjusted appropriately depending on the purpose, but from the viewpoint of providing an emulsifier composition having particularly excellent emulsifying power capable of easily forming and maintaining both stable oil-in-water emulsions and water-in-oil emulsions, the value of m is preferably in the range of 1 to 6, more preferably 2 to 5. In the present invention, the values ​​of n and m and the average values ​​of n and m are each determined from structural analysis using NMR and number average molecular weight measurement calculated in terms of polystyrene using GPC.

[0016] The HLB value of the polyoxyalkylene alkyl ether (A) used in the present invention is not particularly limited and can be adjusted appropriately depending on the purpose, but from the viewpoint of excellent emulsifying power that allows the resulting emulsifier composition to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the HLB value of the polyoxyalkylene alkyl ether (A) is preferably 3.0 to 16.0, more preferably 7.0 to 14.0, even more preferably 8.0 to 12.0, and even more preferably 9.0 to 11.0. In the present invention, when two or more polyoxyalkylene alkyl ethers represented by general formula (1) are used as the polyoxyalkylene alkyl ether (A), the HLB value of the polyoxyalkylene alkyl ether (A) refers to the HLB value of the mixture thereof. In the present invention, the HLB value of the polyoxyalkylene alkyl ether (A) is a value measured in accordance with "20.3.1 Measurement of HLB value by emulsification method" described in "Handbook - Cosmetics and Pharmaceutical Raw Materials - Revised Edition (Nikko Chemicals Co., Ltd.)."

[0017] In the present invention, by containing the specific polyoxyalkylene alkyl ether (A) represented by general formula (1), it is possible to obtain an emulsifier composition that has emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions when combined with a sorbitan monofatty acid ester (B) and a polyhydric alcohol (C) described below.

[0018] The polyoxyalkylene alkyl ether (A) used in the present invention is a polyoxyalkylene alkyl ether (A) represented by the general formula (1) R 1 The polyoxyalkylene alkyl ether (A) may be a polyoxyalkylene alkyl ether having two or more different groups, i.e., a polyoxyalkylene alkyl ether (A) having two or more groups, 1 is an alkyl group having 10 to 17 carbon atoms, and R 1In this case, from the viewpoint of the obtained emulsifier composition being particularly excellent in emulsifying power, which allows both stable oil-in-water emulsions and water-in-oil emulsions to be easily formed and maintained, it is more preferable to use a mixture containing polyoxyalkylene alkyl ether 1 and polyoxyalkylene alkyl ether 2 in a molar ratio of 1:10 to 10:1, and it is even more preferable to use a mixture containing polyoxyalkylene alkyl ether 1 and polyoxyalkylene alkyl ether 2 in a molar ratio of 1:1 to 5:1. Among these, in the present invention, from the viewpoint of the obtained emulsifier composition being particularly excellent in emulsifying power, which allows both stable oil-in-water emulsions and water-in-oil emulsions to be easily formed and maintained, it is preferable to use a mixture containing polyoxyalkylene alkyl ether 1 and polyoxyalkylene alkyl ether 2 in a molar ratio of 1:1 to 5:1. 1 is a dodecyl group, and R in general formula (1) 1 It is preferable to use a mixture of polyoxyalkylene alkyl ether in which R in general formula (1) is a tetradecyl group. 1 is a dodecyl group, and R in general formula (1) 1 It is more preferable to use a mixture containing a polyoxyalkylene alkyl ether in which R is a tetradecyl group in a molar ratio of 1:10 to 10:1, and 1 is a dodecyl group, and R in general formula (1) 1 It is even more preferable to use a mixture containing a polyoxyalkylene alkyl ether in which the alkyl group is a tetradecyl group in a molar ratio of 1:1 to 5:1.

[0019] The sorbitan monofatty acid ester (B) used in the present invention is one or more sorbitan monofatty acid esters selected from the group consisting of sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monooleate. In the present invention, by containing such a specific sorbitan monofatty acid ester (B), it is possible to obtain an emulsifier composition having emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions when combined with the polyoxyalkylene alkyl ether (A) and a polyhydric alcohol (C) described below.

[0020] In the present invention, from the viewpoint that the resulting emulsifier composition has excellent emulsifying power capable of easily forming and maintaining both stable oil-in-water emulsions and water-in-oil emulsions, it is preferable to use, as the sorbitan monofatty acid ester (B), one or more sorbitan monofatty acid esters selected from the group consisting of sorbitan monolaurate, sorbitan monostearate, and sorbitan monooleate, and it is more preferable to use sorbitan monooleate.

[0021] The polyhydric alcohol (C) used in the present invention is one or more polyhydric alcohols selected from the group consisting of 1,2-alkanediols having 6 to 18 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms. Among these, examples of 1,2-alkanediols having 6 to 18 carbon atoms include 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol, 1,2-nonanediol, 1,2-decanediol, 1,2-undecanediol, 1,2-dodecanediol, 1,2-tridecanediol, 1,2-tetradecanediol, 1,2-pentadecanediol, 1,2-hexadecanediol, 1,2-heptadecanediol, and 1,2-octadecanediol. Furthermore, examples of monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms include hexyl glyceryl ether, heptyl glyceryl ether, octyl glyceryl ether, 2-ethylhexyl glyceryl ether, cyclohexyl glyceryl ether, etc. In the present invention, by containing such a polyhydric alcohol (C), it is possible to obtain an emulsifier composition that has emulsifying power that enables it to easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions when combined with the polyoxyalkylene alkyl ether (A) and the sorbitan monofatty acid ester (B).

[0022] In the present invention, from the viewpoint that the resulting emulsifier composition has excellent emulsifying power capable of easily forming and maintaining both stable oil-in-water emulsions and water-in-oil emulsions, it is preferred to use, as the polyhydric alcohol (C), one or more polyhydric alcohols selected from the group consisting of 1,2-alkanediols having 6 to 10 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms, and it is also preferred to use 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol, 1, It is more preferable to use one or more selected from the group consisting of 2-nonanediol, 1,2-decanediol, hexyl glyceryl ether, octyl glyceryl ether, 2-ethylhexyl glyceryl ether, and cyclohexyl glyceryl ether, and it is even more preferable to use one or more selected from the group consisting of 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, 2-ethylhexyl glyceryl ether, and cyclohexyl glyceryl ether.

[0023] The emulsifier composition of the present invention is an emulsifier composition containing the above-mentioned polyoxyalkylene alkyl ether (A), sorbitan monofatty acid ester (B), and polyhydric alcohol (C). The contents of the polyoxyalkylene alkyl ether (A), sorbitan monofatty acid ester (B), and polyhydric alcohol (C) in the emulsifier composition of the present invention are not particularly limited and can be appropriately adjusted depending on the purpose. In the present invention, from the viewpoint of achieving excellent emulsifying power capable of easily forming and maintaining both stable oil-in-water emulsions and water-in-oil emulsions, the content of the polyoxyalkylene alkyl ether (A) is preferably 10 to 60% by mass, the content of the sorbitan mono-fatty acid ester (B) is 30 to 80% by mass, and the content of the polyhydric alcohol (C) is preferably 1 to 30% by mass, more preferably the content of the polyoxyalkylene alkyl ether (A) is 20 to 50% by mass, the content of the sorbitan mono-fatty acid ester (B) is 40 to 70% by mass, and the content of the polyhydric alcohol (C) is 2 to 25% by mass, and even more preferably the content of the polyoxyalkylene alkyl ether (A) is 30 to 45% by mass, the content of the sorbitan mono-fatty acid ester (B) is 45 to 60% by mass, and the content of the polyhydric alcohol (C) is 3 to 20% by mass, relative to the total amount of the emulsifier composition. The emulsifier composition of the present invention contains the polyoxyalkylene alkyl ether (A), the sorbitan monofatty acid ester (B), and the polyhydric alcohol (C) in such content ratios, and thus can easily form and maintain both oil-in-water emulsions and water-in-oil emulsions, such as an oil-in-water emulsion in which the oil to water content ratio in the emulsion is 10:90 by mass, and a water-in-oil emulsion in which the oil to water content ratio in the emulsion is 90:10 by mass.

[0024] Furthermore, the content ratio of the polyoxyalkylene alkyl ether (A) to the sorbitan monofatty acid ester (B) in the emulsifier composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose. However, from the viewpoint of achieving superior emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the content ratio of the polyoxyalkylene alkyl ether (A) to the sorbitan monofatty acid ester (B) in the emulsifier composition is preferably 15:85 to 67:33, more preferably 25:75 to 55:45, and even more preferably 33:67 to 50:50, by mass.

[0025] Furthermore, the content ratio of the polyoxyalkylene alkyl ether (A) to the polyhydric alcohol (C) in the emulsifier composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose. However, from the viewpoint of achieving superior emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the content ratio of the polyoxyalkylene alkyl ether (A) to the polyhydric alcohol (C) in the emulsifier composition is preferably 30:80 to 98:2, more preferably 45:55 to 95:5, and even more preferably 60:40 to 90:10, by mass.

[0026] Furthermore, the content ratio of the sorbitan monofatty acid ester (B) to the polyhydric alcohol (C) in the emulsifier composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose. However, from the viewpoint of achieving superior emulsifying power that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the content ratio of the sorbitan monofatty acid ester (B) to the polyhydric alcohol (C) in the emulsifier composition is preferably 50:50 to 98:2, more preferably 65:35 to 96:4, and even more preferably 70:30 to 95:5, by mass.

[0027] The emulsifier composition of the present invention may consist only of the polyoxyalkylene alkyl ether (A), sorbitan monofatty acid ester (B), and polyhydric alcohol (C) described above, or may contain other compounds within a range that does not impair the effects of the present invention. However, from the viewpoint of making it easier to obtain the effects of the present invention, it is preferable that the emulsifier composition of the present invention consists only of the polyoxyalkylene alkyl ether (A), sorbitan monofatty acid ester (B), and polyhydric alcohol (C).

[0028] The emulsifier composition of the present invention preferably has a transparent appearance from the viewpoint of ease of handling during use, etc. The emulsifier composition of the present invention can have a transparent appearance by, for example, containing the polyoxyalkylene alkyl ether (A), the sorbitan monofatty acid ester (B), and the polyhydric alcohol (C) in the above-mentioned ratios.

[0029] The use of the emulsifier composition of the present invention is not particularly limited as long as it is a known use for which an emulsifier is used, but from the viewpoint of the effects of the present invention, it is preferably used as an emulsifier for lubricating oil, fuel oil, processing oil, or hydraulic oil, more preferably used as an emulsifier for lubricating oil or fuel oil, and even more preferably used as an emulsifier for lubricating oil.

[0030] The lubricant composition of the present invention is a lubricant composition containing the above-mentioned emulsifier composition and a base oil (D). In the present invention, by containing such an emulsifier composition, it is possible to obtain a lubricant composition that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions. The base oil that can be used in the lubricant composition of the present invention is not particularly limited and can be appropriately selected from mineral base oils, chemically synthesized base oils, animal and vegetable base oils, and mixed base oils thereof, depending on the purpose and conditions of use. Furthermore, only one of these can be used, or two or more can be used.

[0031] Examples of mineral base oils include paraffinic mineral oils, naphthenic mineral oils, aromatic mineral oils, and the like, as well as distillate oils obtained by atmospheric distillation of these oils, distillate oils obtained by vacuum distillation of residual oils from atmospheric distillation, and refined oils obtained by refining these oils in accordance with conventional methods, specifically solvent refined oils, hydrogenated refined oils, dewaxed oils, and clay-treated oils.

[0032] Examples of chemically synthesized base oils include poly-α-olefins, polyisobutylene (polybutene), monoesters, diesters, polyol esters, silicate esters, polyalkylene glycols, polyphenyl ethers, silicones, fluorinated compounds, alkylbenzenes, and GTL base oils. Among these, poly-α-olefins, polyisobutylene (polybutene), diesters, and polyol esters can be widely used. Examples of poly-α-olefins include polymers or oligomers of 1-hexene, 1-octene, 1-nonene, 1-decene, 1-dodecene, and 1-tetradecene, as well as hydrogenated versions of these. Examples of diesters include diesters of dibasic acids such as glutaric acid, adipic acid, azelaic acid, sebacic acid, and dodecanedioic acid with alcohols such as 2-ethylhexanol, octanol, decanol, dodecanol, and tridecanol. Examples of polyol esters include esters of polyols such as neopentyl glycol, trimethylolethane, trimethylolpropane, pentaerythritol, dipentaerythritol, and tripentaerythritol with fatty acids such as caproic acid, caprylic acid, lauric acid, capric acid, myristic acid, palmitic acid, stearic acid, and oleic acid.

[0033] Examples of animal and vegetable base oils include vegetable oils such as castor oil, olive oil, cacao butter, sesame oil, rice bran oil, safflower oil, soybean oil, camellia oil, corn oil, rapeseed oil, palm oil, palm kernel oil, sunflower oil, cottonseed oil, and coconut oil, and animal oils such as beef tallow, lard, milk fat, fish oil, and whale oil.

[0034] The content of base oil (D) in the lubricant composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose, but from the viewpoint of obtaining a lubricant composition that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, it is preferably 70 to 99.9 mass %, more preferably 75 to 99.5 mass %, even more preferably 80 to 99 mass %, and particularly preferably 85 to 95 mass % based on the total amount of the lubricant composition. The viscosity of the base oil (D) used in the lubricant composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose, but from the viewpoint of the effects of the present invention, it is preferable that the kinematic viscosity at 100°C is 0.1 to 1000 mm 2 / s, and 1.0 to 800 mm 2 / s is more preferable, and 1.2 to 600 mm 2 In the present invention, the kinematic viscosity at 100°C of the base oil (D) is a value obtained by measurement according to the method described in JIS K 2283.

[0035] The content of the emulsifier composition in the lubricant composition of the present invention is not particularly limited and can be adjusted appropriately depending on the purpose. However, from the viewpoint of obtaining a lubricant composition that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions, the content of the emulsifier composition in the lubricant composition is preferably 0.1 to 30 mass %, more preferably 0.5 to 25 mass %, even more preferably 1.0 to 20 mass %, and particularly preferably 5.0 to 15 mass %, relative to the total amount of the lubricant composition.

[0036] The lubricant composition of the present invention preferably has a transparent appearance from the viewpoint of ease of handling during use, etc. The lubricant composition of the present invention can have a transparent appearance by, for example, containing the above-mentioned emulsifier composition and base oil in the above-mentioned ratio.

[0037] The lubricant composition of the present invention may contain water during storage, use, etc. When the lubricant composition of the present invention contains water, the content thereof is not particularly limited and can be adjusted appropriately depending on the purpose, but may contain, for example, 0.1 to 99.9 mass% of the total amount of the lubricant composition. In this case, from the viewpoint of enabling the lubricant composition to form and maintain a stable emulsion, the water content is preferably 1.0 to 99.0 mass%, more preferably 5.0 to 95 mass%, and even more preferably 10 to 90 mass%, of the total amount of the lubricant composition.

[0038] The use of the lubricant composition of the present invention is not particularly limited as long as it is a known use for a lubricant. However, from the viewpoint of the effects of the present invention, it is preferably used as a lubricant for lubricating oil, fuel oil, processing oil, or hydraulic oil, more preferably used as a lubricant for lubricating oil or fuel oil, and even more preferably used as a lubricant for lubricating oil.

[0039] When the lubricant composition of the present invention is used as a lubricant for lubricating oils, from the viewpoint of the effects of the present invention, it is preferable that the base oil (D) of the lubricant composition or lubricating oil composition contains at least one mineral base oil or chemical synthetic base oil, and more preferably contains a paraffinic highly refined mineral oil, a poly-α-olefin-based or a GTL-based chemical synthetic base oil. In this case, it is preferable that the paraffinic highly refined mineral oil, the poly-α-olefin-based or the GTL-based chemical synthetic base oil is contained in a total amount of 50 mass% or more of the total amount of base oil, and even more preferably 90 mass% or more. When the lubricant composition of the present invention is used as a lubricant for lubricating oils, the content of the base oil (D) in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the purpose, but it is preferably 20 to 98 mass% relative to the total amount of the lubricating oil composition. In this case, the viscosity of the base oil (D) is not particularly limited, but from the viewpoint of the various properties of the lubricating oil composition, it is preferable that the kinematic viscosity at 100 ° C is 0.8 to 16.0 mm 2 / s, and 1.0 to 12.0 mm 2 / s is more preferable, and 1.2 to 10.0 mm 2In the present invention, the kinematic viscosity at 100°C is a value obtained by measurement according to the method described in JIS K 2283.

[0040] When the lubricant composition of the present invention is used as a lubricant for lubricating oils, known additives may be further blended as appropriate depending on the intended use, and the lubricant composition may be used as such, as long as the effects of the present invention are not impaired. For example, friction and wear modifiers, metal-based detergents, antioxidants, extreme pressure agents, ashless dispersants, oiliness improvers, rust inhibitors, viscosity index improvers, metal deactivators, antifoaming agents, solid lubricants, etc. may be blended.

[0041] Examples of friction and wear modifiers include organic molybdenum compounds such as molybdenum dithiocarbamate, molybdenum dithiophosphate, molybdenum long-chain amine salts and molybdenum alkenyl succinimide complexes, and phosphorus compounds such as organic phosphines, organic phosphine oxides, organic phosphinites, organic phosphonites, organic phosphinates, organic phosphites, organic phosphonates, organic phosphates and organic phosphoramidates. When the lubricating oil composition contains a friction and wear modifier, the content of the friction and wear modifier in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but for example, it is preferably contained in an amount of 0.05 to 10 mass%, more preferably 0.10 to 5.0 mass%, based on the total amount of the lubricating oil composition.

[0042] Examples of metallic detergents include alkaline earth metal sulfonates, alkaline earth metal phenates, alkaline earth metal salicylates, and alkaline earth metal phosphonates, and examples of alkaline earth metals include magnesium, calcium, and barium. Among these, from the viewpoint of further enhancing the effects of the present invention, it is preferable to use at least one metallic detergent selected from the group consisting of calcium-based detergents and magnesium-based detergents, and it is more preferable to use one or more calcium-based detergents and one or more magnesium-based detergents. When the lubricating oil composition contains a metallic detergent, the content of the metallic detergent in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but for example, the total content of calcium atoms and magnesium atoms is preferably 0.05 to 0.50 mass%, more preferably 0.10 to 0.40 mass%, based on the total amount of the lubricating oil composition.

[0043] Examples of antioxidants include amine-based antioxidants, phenol-based antioxidants, phenothiazine-based antioxidants, thioether-based antioxidants, and phosphite-based antioxidants, and among these, it is preferable to use at least one antioxidant selected from the group consisting of phenol-based antioxidants and amine-based antioxidants. When the lubricating oil composition contains an antioxidant, the content of the antioxidant in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be, for example, 0.01 to 10 mass% based on the total amount of the lubricating oil composition.

[0044] Examples of extreme pressure agents include sulfur-based extreme pressure agents such as sulfurized fats and oils, sulfurized mineral oils, organic mono- or polysulfides, sulfides of polyolefins, 1,3,4-thiadiazole derivatives, thiuram disulfides, and dithiocarbamic acid esters, and thiophosphate-based extreme pressure agents such as organic trithiophosphites and organic thiophosphates. When the lubricating oil composition contains an extreme pressure agent, the content of the extreme pressure agent in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 10 mass% based on the total amount of the lubricating oil composition.

[0045] Examples of ashless dispersants include alkenyl succinimides, alkenyl succinic anhydrides, alkenyl succinic acid esters, alkyl methacrylate polymers, high molecular weight amides and polyamides, polyesters, polyvinyl polystearates, Mannich base dispersants, polystearamides, and modified products thereof modified with boric acid, etc. When the lubricating oil composition contains an ashless dispersant, the content of the ashless dispersant in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 10 mass % relative to the total amount of the lubricating oil composition.

[0046] Examples of oiliness improvers include fatty acids, fats and oils and hydrogenated or partially saponified products thereof, epoxidized esters, polycondensates of hydroxystearic acid or esters of such polycondensates with fatty acids, higher alcohols, higher amides, glycerides, glycerin monofatty acid esters, polyglycerin esters, polyglycerin ethers, and adducts of the above compounds with α-olefin oxides. When the lubricating oil composition contains an oiliness improver, the content of the oiliness improver in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 30 mass% based on the total amount of the lubricating oil composition.

[0047] Examples of rust inhibitors include oxidized paraffin wax calcium salt, oxidized paraffin wax magnesium salt, tallow fatty acid alkali metal salt, alkaline earth metal salt or amine salt, alkenylsuccinic acid or alkenylsuccinic acid half ester (the molecular weight of the alkenyl group is about 100 to 300), sorbitan monoester, pentaerythritol monoester, glycerin monoester, nonylphenol ethoxylate, lanolin fatty acid ester, lanolin fatty acid calcium salt, etc. When the lubricating oil composition contains a rust inhibitor, the content of the rust inhibitor in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 20 mass % based on the total amount of the lubricating oil composition.

[0048] Examples of viscosity index improvers include poly(C1-18) alkyl methacrylate, (C1-18) alkyl acrylate / (C1-18) alkyl methacrylate copolymer, diethylaminoethyl methacrylate / (C1-18) alkyl methacrylate copolymer, ethylene / (C1-18) alkyl methacrylate copolymer, polyisobutylene, polyalkylstyrene, ethylene / propylene copolymer, styrene / maleic acid ester copolymer, styrene / maleic acid amide copolymer, styrene / butadiene hydrogenated copolymer, styrene / isoprene hydrogenated copolymer, etc., and the average molecular weight may be about 10,000 to 1,500,000. When the lubricating oil composition contains a viscosity index improver, the content of the viscosity index improver in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 20 mass% based on the total amount of the lubricating oil composition.

[0049] Examples of metal deactivators include N,N'-salicylidene-1,2-propanediamine, alizarin, tetraalkylthiuram disulfide, benzotriazole, benzimidazole, 2-alkyldithiobenzimidazole, 2-alkyldithiobenzothiazole, 2-(N,N-dialkylthiocarbamoyl)benzothiazole, 2,5-bis(alkyldithio)-1,3,4-thiadiazole, 2,5-bis(N,N-dialkylthiocarbamoyl)-1,3,4-thiadiazole, etc. When the lubricating oil composition contains a metal deactivator, the content of the metal deactivator in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.1 to 10 mass% based on the total amount of the lubricating oil composition.

[0050] Examples of antifoaming agents include polydimethyl silicone, trifluoropropylmethyl silicone, colloidal silica, polyalkyl acrylate, polyalkyl methacrylate, alcohol ethoxy / propoxylate, fatty acid ethoxy / propoxylate, etc. When the lubricating oil composition contains an antifoaming agent, the content of the antifoaming agent in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 10 mass % relative to the total amount of the lubricating oil composition.

[0051] Examples of solid lubricants include graphite, molybdenum disulfide, polytetrafluoroethylene, alkaline earth metal salts of fatty acids, mica, cadmium dichloride, cadmium diiodide, calcium fluoride, lead iodide, lead oxide, titanium carbide, titanium nitride, aluminum silicate, antimony oxide, cerium fluoride, polyethylene, diamond powder, silicon nitride, boron nitride fluorocarbon, melamine isocyanurate, etc. When the lubricating oil composition contains a solid lubricant, the content of the solid lubricant in the lubricating oil composition is not particularly limited and can be adjusted appropriately depending on the intended use, etc., but can be contained in an amount of, for example, 0.01 to 5 mass% based on the total amount of the lubricating oil composition.

[0052] When the lubricant composition of the present invention is used as a lubricant for lubricating oils, from the viewpoint of obtaining a lubricant composition that can further reduce oil-water interfacial tension, it is preferable that the composition further contains a glycerin monofatty acid ester (E) composed of an ester of a fatty acid having 12 to 20 carbon atoms and glycerin. In this case, examples of the fatty acid having 12 to 20 carbon atoms include lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, and oleic acid, and one or more of these may be used. In the present invention, from the viewpoint of obtaining a lubricant composition that can further reduce oil-water interfacial tension, it is preferable to use, as the glycerin monofatty acid ester (E), a glycerin monofatty acid ester composed of an ester of a fatty acid having 14 to 20 carbon atoms and glycerin, more preferably a glycerin monofatty acid ester composed of an ester of a fatty acid having 16 to 20 carbon atoms and glycerin, and even more preferably a glycerin monofatty acid ester composed of an ester of oleic acid and glycerin (glycerin monooleate). When the lubricant composition of the present invention contains the glycerin monofatty acid ester (E), the oil-water interfacial tension can be further reduced, which is expected to result in a further improvement in emulsion stability, such as a finer and more uniform emulsion particle size upon emulsification.

[0053] When the lubricant composition of the present invention contains a glycerol monofatty acid ester (E), the content of the glycerol monofatty acid ester (E) in the lubricant composition is not particularly limited and can be adjusted appropriately depending on the purpose. However, from the viewpoint of providing a lubricant composition that can easily form and maintain both stable oil-in-water emulsions and water-in-oil emulsions and further reducing the oil-water interfacial tension, the content of the glycerol monofatty acid ester (E) is preferably 0.01 to 20 mass %, more preferably 0.1 to 10 mass %, even more preferably 0.2 to 5 mass %, and particularly preferably 0.5 to 3 mass %, relative to the total amount of the lubricant composition.

[0054] When the lubricant composition of the present invention is used as a lubricant for lubricating oils, the viscosity of the lubricant composition is not particularly limited and can be adjusted appropriately depending on the intended use and properties. From the viewpoint of the effects of the present invention, however, it is preferable that the kinematic viscosity at 100°C is 4.0 to 16.0 mm2 / s, and 5.0 to 12.0 mm 2 / s is more preferable, and 6.0 to 10.0 mm 2 In the present invention, the kinematic viscosity at 100°C is a value obtained by measurement according to the method described in JIS K 2283.

[0055] When the lubricant composition of the present invention is used as a lubricant for lubricating oils, the manner of use of the lubricant composition is not particularly limited, and it can be used, for example, as a lubricant for internal combustion engines (for example, gasoline engines, diesel engines, hybrid engines, etc. of automobiles, motorcycles, etc.), industrial lubricant (for example, gear oil, turbine oil, oil film bearing oil, lubricant for refrigerators, vacuum pump oil, lubricant for compression, multi-purpose lubricant, etc.), etc. Among these, it is preferably used as a lubricant composition for internal combustion engines such as gasoline engines, diesel engines, hybrid engines, etc., because the effects of the present invention can be easily obtained.

[0056] The present disclosure includes the following aspects.

[0057] [1] An emulsifier composition containing (A) a polyoxyalkylene alkyl ether represented by general formula (1), (B) one or more sorbitan monofatty acid esters selected from the group consisting of sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monooleate, and (C) one or more polyhydric alcohols selected from the group consisting of 1,2-alkanediols having 6 to 18 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms.

[0058] [2] The emulsifier composition according to [1], wherein the content of the polyoxyalkylene alkyl ether (A) is 10 to 60 mass%, the content of the sorbitan monofatty acid ester (B) is 30 to 80 mass%, and the content of the polyhydric alcohol (C) is 1 to 30 mass%, based on the total amount of the emulsifier composition.

[0059] [3] The polyoxyalkylene alkyl ether (A) is a compound represented by the general formula (1), wherein R1 is an alkyl group having 12 to 14 carbon atoms, and the average values ​​of n and m are each independently a number from 1 to 10.

[0060] [4] The emulsifier composition according to any one of [1] to [3], wherein the polyhydric alcohol (C) is one or more polyhydric alcohols selected from the group consisting of 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, 2-ethylhexyl glyceryl ether, and cyclohexyl glyceryl ether.

[0061] [5] A lubricant composition comprising the emulsifier composition according to any one of [1] to [4] and a base oil (D).

[0062] [6] The lubricant composition according to [5], wherein the base oil (D) is a mineral base oil.

[0063] [7] The lubricant composition according to [5] or [6], further comprising a glycerin mono-fatty acid ester (E) consisting of an ester of a fatty acid having 12 to 20 carbon atoms and glycerin.

[0064] The present invention will be described in more detail below with reference to examples. In the following examples, percentages are by mass unless otherwise specified. The components used in the examples and comparative examples are shown below.

[0065] <Polyoxyalkylene alkyl ether (A)> A-1: ​​In general formula (1), R 1 is a dodecyl group or a tetradecyl group (molar ratio of dodecyl group:tetradecyl group=4:1), the average value of n is 5.8, the average value of m is 2.7, and the HLB value is 10. A-2: Polyoxyalkylene alkyl ether A-2: Polyoxyalkylene alkyl ether A-2 in which, in general formula (1), R 1 A-3: Polyoxyalkylene alkyl ether in which, in general formula (1), R is a dodecyl group, the average value of n is 3, m is 0, and the HLB value is 8. 1 A-4: Polyoxyalkylene alkyl ether in which, in general formula (1), R is an isotridecyl group, the average value of n is 4, the average value of m is 2, and the HLB value is less than 7. 1is a dodecyl group or a tetradecyl group (molar ratio of dodecyl groups:tetradecyl groups = 4:1), the average value of n is 6.5, m is 0, and the HLB value is 12. <Sorbitan mono fatty acid ester (B)> B-1: sorbitan monooleate <Polyhydric alcohol (C)> C-1: 1,2-hexanediol C-2: 1,2-octanediol C-3: 1,2-decanediol C-4: 2-ethylhexyl glyceryl ether C-5: cyclohexyl glyceryl ether <Base oil (D)> D-1: paraffinic group I mineral oil (kinematic viscosity at 100°C = 8.8 mm 2 / s) <Glycerin mono fatty acid ester (E)> E-1: Glycerin monooleate

[0066] [Preparation of emulsifier compositions] Emulsifier compositions 1 to 11 were prepared by mixing the components as shown in Tables 1 and 2 below. Of these, emulsifier compositions 1 to 5 are emulsifier compositions serving as examples according to the present invention, and emulsifier compositions 6 to 11 are emulsifier compositions serving as comparative examples. In Tables 1 and 2, % represents % by mass.

[0067] [Evaluation of Transparency of Emulsifier Compositions] The appearance of each of emulsifier compositions 1 to 11 was checked immediately after production, and the transparency was evaluated based on the following criteria. The evaluation results are shown in Tables 1 and 2.

[0068] Evaluation criteria for transparency of emulsifier composition: ○: transparent ×: opaque due to turbidity or precipitation

[0069]

[0070]

[0071] [Production of Lubricant Composition 1] Using the prepared emulsifier composition and base oil, lubricant compositions of Examples 6 to 10 and Comparative Examples 7 to 13 were produced, as shown in the following Tables 3 and 4. In Tables 3 and 4, % represents mass %.

[0072] [Evaluation of Transparency of Lubricant Compositions] The appearance of each lubricant composition was checked immediately after production, and the transparency was evaluated based on the following criteria. The evaluation results for each lubricant composition are shown in Tables 3 and 4.

[0073] Evaluation criteria for transparency of lubricant composition: ○: transparent ×: opaque due to turbidity or sedimentation

[0074] [Evaluation of O / W emulsifying power] Oil-in-water (O / W) emulsions were prepared by adding 90 ml of distilled water to 10 ml of each lubricant composition at room temperature while stirring under a room temperature (25°C) environment. The appearance was then observed after standing at room temperature for 24 hours, and the O / W emulsifying power was evaluated based on the following criteria. The evaluation results for each lubricant composition are shown in Tables 3 and 4. In this evaluation, an evaluation result of ○ indicates that the composition has the emulsifying power to form and maintain a stable oil-in-water emulsion. This evaluation result of ○ indicates that the emulsifier composition can be used for lubricants to be mixed with water, and that the emulsifier composition can be used continuously without separation even when a large amount of water is mixed into the lubricant during use.

[0075] Evaluation criteria for O / W emulsifying power: ○: No separation occurred and the O / W emulsion state was maintained. ×: Separation or turbidity occurred.

[0076] [Evaluation of W / O emulsifying power] Water-in-oil (W / O) emulsions were prepared by adding 10 ml of distilled water to 90 ml of each lubricant composition at room temperature while stirring under a room temperature (25°C) environment. The appearance was then observed after standing at room temperature for 24 hours, and the W / O emulsifying power was evaluated based on the following criteria. The evaluation results for each lubricant composition are shown in Tables 3 and 4. In this evaluation, an evaluation result of ○ indicates that the composition has the emulsifying power to form and maintain a stable water-in-oil emulsion. This evaluation result of ○ indicates that the emulsifier composition can be used continuously without separation, even if a small amount of water is mixed into the lubricant when used as a lubricant.

[0077] Evaluation criteria for W / O emulsifying ability: ○: No separation occurred and the W / O emulsion state was maintained. ×: Separation or turbidity occurred.

[0078]

[0079]

[0080] As described above, it can be seen that the emulsifier composition of the present invention can prepare a lubricant composition that can easily form and maintain, even at room temperature, an oil-in-water emulsion in which the oil to water ratio in the emulsion is 10:90 by mass, or a water-in-oil emulsion in which the oil to water ratio in the emulsion is 90:10 by mass. On the other hand, it can be seen that an emulsifier composition that does not contain at least one of the polyoxyalkylene alkyl ether (A), the sorbitan monofatty acid ester (B), and the polyhydric alcohol (C) cannot form or maintain either or both of an oil-in-water emulsion and a water-in-oil emulsion.

[0081] [Production of Lubricant Composition 2] Using the prepared emulsifier composition, base oil, and glycerin mono-fatty acid ester, the lubricant composition of Example 11 was produced as shown in Table 5. Also, using the base oil and glycerin mono-fatty acid ester, the lubricant composition of Comparative Example 14 was produced as shown in Table 5. In Table 5, % represents % by mass.

[0082] The transparency, O / W emulsifying power, and W / O emulsifying power of the lubricant compositions produced in Example 11 and Comparative Example 14 were evaluated using the same methods and criteria as those described above in [Evaluation of Transparency of Lubricant Composition], [Evaluation of O / W Emulsifying Power], and [Evaluation of W / O Emulsifying Power]. The evaluation results are shown in Table 5.

[0083] [Measurement of Oil-Water Interfacial Tension] The oil-water interfacial tension was measured for each of the lubricant compositions produced in Example 11 and Comparative Example 14. Specifically, 20 g of water was poured into the measurement vessel of a surface tensiometer (DY-500 manufactured by Kyowa Interface Science Co., Ltd.), and then 80 g of the produced lubricant composition was slowly poured therein so that the lower layer was a water layer and the upper layer was an oil layer (lubricant composition layer). After allowing to stand for 24 hours, the interfacial tension at the interface between the water layer and the oil layer was measured using the Whilhelmy method. The results of each measurement are shown in Table 5. Note that the interfacial tension at the interface between the water layer and the oil layer (base oil layer) measured by the same method, except that base oil D-1 was poured in place of the lubricant composition, was 5.54 mN / m, and the interfacial tension at the interface between the water layer and the oil layer (lubricant composition layer) measured by the same method, except that the lubricant composition produced in Example 7 was poured in was 4.66 mN / m.

[0084]

[0085] From the above results, it can be seen that the lubricant composition of the present invention can significantly reduce the oil-water interfacial tension by further containing a glycerin monofatty acid ester (E) consisting of an ester of a fatty acid having 12 to 20 carbon atoms and glycerin. Since the lubricant composition of Example 11 can significantly reduce the oil-water interfacial tension, further improvement in emulsion stability can be expected, such as the emulsion particle size becoming finer and more uniform during emulsification.

Claims

1. An emulsifier composition containing a polyoxyalkylene alkyl ether (A) represented by the following general formula (1), one or more sorbitan mono-fatty acid esters (B) selected from the group consisting of sorbitan monolaurate, sorbitan monomyristate, sorbitan monopalmitate, sorbitan monostearate, and sorbitan monooleate, and one or more polyhydric alcohols (C) selected from the group consisting of 1,2-alkanediols having 6 to 18 carbon atoms and monoalkyl glyceryl ethers having a hydrocarbon group having 6 to 8 carbon atoms. (In the formula, R 1 represents an alkyl group having 10 to 18 carbon atoms, and the average values of n and m each independently represent a number from 0 to 10. However, at least one of n and m is not 0. The sequence of each structural unit may be block-like or random.) 2. The emulsifier composition according to claim 1, wherein the content of the polyoxyalkylene alkyl ether (A) is 10 to 60% by mass, the content of the sorbitan mono-fatty acid ester (B) is 30 to 80% by mass, and the content of the polyhydric alcohol (C) is 1 to 30% by mass, based on the total amount of the emulsifier composition.

3. In the polyoxyalkylene alkyl ether (A), in the general formula (1), R 1 is an alkyl group having 12 to 14 carbon atoms, and the average values of n and m are each independently a number from 1 to 10, and the emulsifier composition according to claim 1, which is a polyoxyalkylene alkyl ether.

4. The emulsifier composition according to claim 1, wherein the polyhydric alcohol (C) is one or more polyhydric alcohols selected from the group consisting of 1,2 - hexanediol, 1,2 - octanediol, 1,2 - decanediol, 2 - ethylhexyl glyceryl ether, and cyclohexyl glyceryl ether.

5. A lubricant composition comprising the emulsifier composition according to any one of claims 1 to 4 and a base oil (D).

6. The lubricant composition according to claim 5, wherein the base oil (D) is a mineral base oil.

7. The lubricant composition according to claim 5, further comprising a glycerin mono-fatty acid ester (E) composed of an ester of a fatty acid having 12 to 20 carbon atoms and glycerin.

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