Patent Application
20240344157
The present invention relates to a heat treating oil composition.
Metal materials, such as a steel material, may be subjected to heat treatments, such as quenching, tempering, annealing, and normalizing, for the purpose of improving the properties thereof. In these heat treatments, quenching is a treatment of immersing a heated metal material into a cooling medium to transform into the prescribed quenched structure. The metal material becomes significantly hard through the quenching, and the mechanical strength thereof is enhanced.
A heat treating oil composition has been widely used as the cooling medium for quenching. The heat treating oil composition is demanded to have a capability as a cooling medium, and also a capability of retaining the surface glossiness of the metal material before quenching even after the quenching, from the standpoint of enhancing the market value of the metal material after quenching. Accordingly, the heat treating oil composition is demanded to have a capability of improving the brightness of a metal material after quenching.
As the heat treating oil composition, for example, a heat treating oil composition using a base oil having a total sulfur content regulated to 3 to 1,000 ppm by blending at least one kind of sulfur and a sulfur compound in at least one kind of a mineral oil and a synthetic oil having a sulfur content of 300 ppm or less, and the like have been proposed (see, for example, PTL 1).
However, as a result of the earnest investigations by the present inventors, it has been found that a part of the sulfur compounds exemplified in PTL 1 (for example, diphenyl disulfide) is inferior in the effect of improving the brightness of a metal material after quenching.
From the standpoint of enabling the use of a wide range of various sulfur compounds, it is considered that the establishment of the formulation of a heat treating oil composition capable of improving the brightness is desirable even with the use of a sulfur compound that is inferior in the effect of improving the brightness of a metal material after quenching.
Furthermore, the heat treating oil composition is also demanded to have excellent oxidation stability, assuming the contact and the like with air in the use thereof in an open oil tank.
Under the circumstances, a problem to be solved by the present invention is to provide a heat treating oil composition that can improve the brightness of a metal material after a heat treatment, such as quenching, even with the use of a sulfur compound that is inferior in the effect of improving the brightness, and is excellent in oxidation stability.
The present invention provides the following items [1] to [3].
[1] A heat treating oil composition containing:
in which
[2] A method of using a heat treating oil composition, including using the heat treating oil composition according to the item [1] as a quenching oil or a tempering oil.
[3] A method for producing a heat treating oil composition, including a step of mixing one or more kinds of a base oil (A) selected from the group consisting of a mineral oil (A1), a synthetic oil (A2), and a vegetable oil (A3), a sulfur compound (B), and a carboxylic acid-based compound (C),
in which
The present invention can provide a heat treating oil composition that can improve the brightness of a metal material after a heat treatment, such as quenching, even with the use of a sulfur compound that is inferior in the effect of improving the brightness, and is excellent in oxidation stability.
In the description herein, the lower limit values and the upper limit values described in a stepwise manner for the preferred numerical ranges (such as the range of the content or the like) each may be independently combined. For example, from the description “preferably 10 to 90, and more preferably 30 to 60”, a range of “10 to 60” may be derived from the “preferred lower limit value (10)” and the “more preferred upper limit value (60)”.
In the description herein, the numerical range “lower limit value to upper limit value” means the lower limit value or more and the upper limit value or less unless otherwise indicated.
In the description herein, the numerical values in the examples can be used as the upper limit value or the lower limit value.
In the description herein, the “kinematic viscosity at 40° C.” may be referred simply to as a “40° C. kinematic viscosity”.
The heat treating oil composition of the present embodiment contains one or more kinds of a base oil (A) selected from the group consisting of a mineral oil (A1), a synthetic oil (A2) and a vegetable oil (A3), a sulfur compound (B), and a carboxylic acid-based compound (C).
The sulfur compound (B) contains one or more kinds selected from the group consisting of a sulfide compound (B1) represented by the following general formula (b1), a sulfide compound (B2) represented by the following general formula (b2), a sulfide compound (B3) represented by the following general formula (b3), and a sulfide compound (B4) represented by the following general formula (b4).
The carboxylic acid-based compound (C) is one or more kinds selected from the group consisting of a compound having at least one carboxy group, and an anhydride thereof
In the general formula (b1), Ar11 represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group, and R11 represents a substituted or unsubstituted hydrocarbon group (X1), in which the hydrocarbon group (X1) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms.
In the general formula (b2), Ar12 represents an arylene group having 6 to 15 carbon atoms having at least a hydroxy group, and R12 and R13 each independently represent a substituted or unsubstituted hydrocarbon group (X2), in which the hydrocarbon group (X2) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms.
In the general formula (b3), Ar13 represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group, and Ar14 represents a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
In the general formula (b4), Ar15 and Ar16 each independently represent a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
The present inventors have made earnest investigations for solving the problem. As a result, it has been found that the problem can be solved by the combination use of the sulfur compound (B) that is inferior in the effect of improving the brightness of a metal material after a heat treatment, such as quenching, and the carboxylic acid-based compound (C).
According to the investigations by the present inventors, the effect of improving the brightness cannot be observed even through only the carboxylic acid-based compound (C) is blended in the base oil (A). It is estimated therefrom that the combination use of the sulfur compound (B) and the carboxylic acid-based compound (C) generates a certain kind of interaction between the compounds, which derives the effect of improving the brightness of the sulfur compound (B), resulting in the achievement of the effects of the present invention.
The heat treating oil composition of the present embodiment may be constituted only by the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C), and may contain an additional component other than the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C), in such a range that does not impair the effects of the present invention.
In the present embodiment, the total content of the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C) is preferably 75% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, further preferably 85% by mass to 100% by mass, still further preferably 90% by mass to 100% by mass, and still more further preferably 95% by mass to 100% by mass, based on the total amount of the heat treating oil composition.
The components constituting the heat treating oil composition of the present invention will be described in detail below.
The heat treating oil composition of the present embodiment contains a base oil (A).
The base oil (A) is one or more kinds selected from the group consisting of a mineral oil (A1), a synthetic oil (A2), and a vegetable oil (A3).
The mineral oil (A1), the synthetic oil (A2), and the vegetable oil (A3) will be described in detail below.
The mineral oil (A1) used may be a mineral oil that has been generally used in a heat treating oil composition, with no particular limitation.
Specific examples of the mineral oil (A1) include an atmospheric residual oil obtained by subjecting a crude oil, such as a paraffin base crude oil, an intermediate base crude oil, and a naphthene base crude oil, to atmospheric distillation; a distillate oil obtained by subjecting the atmospheric residual oil to distillation under reduced pressure; a mineral oil obtained by subjecting the distillate oil to one or more treatments of solvent deasphalting, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydro-refining, and the like; and a wax isomerization mineral oil.
The mineral oil (A1) is preferably a highly refined mineral oil having a reduced sulfur content obtained by performing a refining treatment including at least one kind of hydrocracking and hydro-refining.
The sulfur content of the highly refined mineral oil is preferably less than 10 ppm by mass, more preferably less than 5 ppm by mass, and further preferably less than 3 ppm by mass, based on the total amount of the highly refined mineral oil.
The mineral oil (A1) may also be a bright stock having a small sulfur content.
In the description herein, the “bright stock” means a high viscosity mineral oil (40° C. kinematic viscosity: approximately 350 mm2/s to 550 mm2/s) obtained in such a manner that an atmospheric residual oil obtained by subjecting a crude oil, such as a paraffin base crude oil, an intermediate base crude oil, and a naphthene base crude oil, to atmospheric distillation is subjected to distillation under reduced pressure to provide a distillate oil, the distillate oil is then subjected to deasphalting to provide a deasphalted oil, and the deasphalted oil is subjected to one or more kinds of a refining treatment selected from solvent refining, hydro-refining, and the like.
The bright stock having a small sulfur content is preferably a hydro-refined product, and preferably has a sulfur content of less than 10 ppm by mass, more preferably less than 5 ppm by mass, and further preferably less than 3 ppm by mass, based on the total amount of the bright stock.
The bright stock having a small sulfur content is preferably one classified into the Group II in the base oil category of American Petroleum Institute (API).
One kind of the mineral oil (A1) may be used alone, or two or more kinds thereof may be used in combination.
The synthetic oil (A2) used may be a synthetic oil that has been generally used in a heat treating oil composition, with no particular limitation.
Specific examples of the synthetic oil (A2) include a poly-α-olefin compound, a polyphenyl ether, an alkylbenzene, an alkylnaphthalene, a polyphenyl-based hydrocarbon, an ester oil (for example, a fatty acid ester of a polyhydric alcohol, such as neopentyl glycol, trimethylolpropane, and pentaerythritol), a glycol-based synthetic oil, and a GTL base oil obtained by isomerizing wax produced from natural gas by the Fischer-Tropsch process or the like (GTL wax (gas-to-liquids wax)).
Among these, a GTL base oil is preferred.
One kind of the synthetic oil (A2) may be used alone, or two or more kinds thereof may be used in combination.
The vegetable oil (A3) used may be a vegetable oil that has been generally used in a heat treating oil composition, with no particular limitation.
Specific examples of the vegetable oil (A3) include a linseed oil, a safflower oil, a sunflower oil, a soybean oil, a corn oil, a cotton seed oil, a sesame seed oil, an olive oil, a castor oil, a peanut oil, a coconut palm oil, a palm kernel oil, a palm oil, a coconut oil, a canola oil, and a rice bran oil.
One kind of the vegetable oil (A3) may be used alone, or two or more kinds thereof may be used in combination.
In the present embodiment, it suffices that the base oil (A) is one or more kinds selected from the group consisting of the mineral oil (A1), the synthetic oil (A2), and the vegetable oil (A3), and is preferably one or more kinds selected from the group consisting of the mineral oil (A1) and the synthetic oil (A2).
The base oil (A) preferably contains the mineral oil (A1). In the case where the base oil (A) contains the mineral oil (A1), the content of the mineral oil (A1) is preferably 20% by mass to 100% by mass, more preferably 30% by mass to 100% by mass, further preferably 40% by mass to 100% by mass, still further preferably 50% by mass to 100% by mass, still more further preferably 60% by mass to 100% by mass, even further preferably 70% by mass to 100% by mass, even still further preferably 80% by mass to 100% by mass, and even still more further preferably 90% by mass to 100% by mass, based on the total amount of the base oil (A).
The 40° C. kinematic viscosity of the base oil (A) used in the present embodiment is preferably 5 mm2/s to 600 mm2/s, more preferably 6 mm2/s to 570 mm2/s, further preferably 7 mm2/s to 540 mm2/s, still further preferably 8 mm2/s to 520 mm2/s, and still more further preferably 9 mm2/s to 500 mm2/s.
In the case where the 40° C. kinematic viscosity of the base oil (A) is 5 mm2/s or more, a heat treating oil composition with suppressed oil smoke can be readily obtained. In the case where the 40° C. kinematic viscosity of the base oil (A) is 600 mm2/s or less, a heat treating oil composition having a good cooling capability can be readily obtained.
In the description herein, the 40° C. kinematic viscosity is a value that is measured according to JIS K2283:2000.
The heat treating oil composition of the present embodiment preferably contains multiple kinds of base oils different in 40° C. kinematic viscosity mixed with each other in consideration of the facilitation of regulation of the 40° C. kinematic viscosity of the base oil (A).
In the heat treating oil composition of the present embodiment, the content of the base oil (A) is preferably 80.0% by mass or more, more preferably 82.0% by mass or more, and further preferably 83.0% by mass or more, and is preferably 98.99% by mass or less, based on the total amount of the heat treating oil composition.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the content thereof is preferably 80.0% by mass to 98.99% by mass, more preferably 82.00% by mass to 98.99% by mass, and further preferably 83.0% by mass to 98.99% by mass.
The heat treating oil composition of the present embodiment contains the sulfur compound (B).
The sulfur compound (B) is inferior in the effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) can improve the brightness of a metal material after a heat treatment, such as quenching.
In the present embodiment, the sulfur compound (B) contains one or more kinds selected from the group consisting of the sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4).
In the present embodiment, the sulfur compound (B) may be formed only of one or more kinds selected from the group consisting of the sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4), and may contain an additional sulfur compound other than the sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4) in such a range that does not impair the effects of the present invention.
In the present embodiment, the one or more kinds selected from the group consisting of the sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4) encompasses the following embodiments.
In the present embodiment, the content of one or more kinds selected from the group consisting of the sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4) is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, and still further preferably 95% by mass to 100% by mass, based on the total amount of the sulfur compound (B).
The sulfide compound (B1), the sulfide compound (B2), the sulfide compound (B3), and the sulfide compound (B4) will be described in detail below.
The sulfide compound (B1) is a compound represented by the following general formula (b1).
In the general formula (b1), Ar11 represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group.
A structure having a sulfur atom and an aryl group bonded via a methylene group, as in the compound represented by the general formula (b1), tends to have an inferior effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) can improve the brightness of a metal material after a heat treatment, such as quenching.
In the case where the number of carbon atoms of the aryl group exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
In the general formula (b1), examples of the aryl group having 6 to 15 carbon atoms constituting Ar11 include a phenyl group, a biphenylyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, and an anthryl group.
The expression “having 6 to 15 carbon atoms” in the “aryl group having 6 to 15 carbon atoms” means “6 to 15 ring carbon atoms”.
The number of carbon atoms of the aryl group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
In the general formula (b1), the aryl group having 6 to 15 carbon atoms constituting Ar11 has at least one or more hydroxy groups. In the case where the aryl group does not have a hydroxy group, there is a concern that the oxidation stability of the heat treating oil composition is insufficient.
The aryl group may further have a substituent other than a hydroxy group, or may not have a substituent other than a hydroxy group.
Examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, an amide group, a benzamide group, a carboxy group, a residual group obtained by removing one hydrogen atom from a hydroxy group of a dicarboxylic acid, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
The number of the hydroxy group of the aryl group may be one, or multiple hydroxy groups may exist, and the number thereof is preferably one.
In the case where the aryl group has a substituent other than a hydroxy group, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
In the general formula (b1), R11 represents a substituted or unsubstituted hydrocarbon group (X1).
In the case where the hydrocarbon group (X1) has a substituent, examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, an amide group, a benzamide group, a carboxy group, a residual group obtained by removing one hydrogen atom from a hydroxy group of a dicarboxylic acid, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
In the case where the hydrocarbon group (X1) has a substituent, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
In the general formula (b1), the hydrocarbon group (X1) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms. The number of carbon atoms of the hydrocarbon group (X1) does not include the number of carbon atoms of the substituent that the hydrocarbon group (X1) may have.
In the case where the number of carbon atoms of the group that can be selected as the hydrocarbon group (X1) exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
Examples of the alkyl group having 1 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, a tetradecyl group, and a pentadecyl group.
The alkyl group may be linear or branched.
Examples of the alkenyl group having 2 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include an ethenyl group, a propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, an octenyl group, a nonenyl group, a decenyl group, an undecenyl group, a dodecenyl group, a tridecenyl group, a tetradecenyl group, and a pentadecenyl group.
The alkenyl group may be linear or branched.
Examples of the cycloalkyl group having 3 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cycloheptyl group.
The expression “having 3 to 15 carbon atoms” in the “cycloalkyl group having 3 to 15 carbon atoms” means “3 to 15 ring carbon atoms”.
The number of carbon atoms of the cycloalkyl group is preferably 5 to 10, and more preferably 5 to 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
Examples of the cycloalkenyl group having 3 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group.
The expression “having 3 to 15 carbon atoms” in the “cycloalkenyl group having 3 to 15 carbon atoms” means “3 to 15 ring carbon atoms”.
The number of carbon atoms of the cycloalkenyl group is preferably 5 to 10, and more preferably 5 to 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
Examples of the cycloalkylalkyl group having 4 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a cyclopropylmethyl group, a cyclopropylethyl group, a cyclopropylpropyl group, a cyclopropylbutyl group, a cyclobutylmethyl group, a cyclopentylmethyl group, a cyclopentylethyl group, a cyclopentylpropyl group, a cyclohexylmethyl group, a cyclohexylethyl group, and a cyclohexylpropyl group.
The cycloalkylalkyl group is a group represented by the following general formula (c1), and is a group including an alkyl group, one hydrogen atom of which is substituted by a cycloalkyl group.
In the general formula (c1), the circle represents a cycloalkyl group, R31 represents an alkylene group, and the wavy line represents a bonding site to the carbon atom in the general formula (b1).
The expression “having 4 to 15 carbon atoms” in the “cycloalkylalkyl group having 4 to 15 carbon atoms” means the total number of carbon atoms of the number of ring carbon atoms of the cycloalkyl group and the number of carbon atoms of the alkylene group (R31).
The number of carbon atoms (i.e., the number of ring carbon atoms) of the cycloalkyl group constituting the cycloalkylalkyl group is preferably 5 to 10, and more preferably 5 to 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
The number of carbon atoms of the alkylene group constituting the cycloalkylalkyl group is preferably 1 to 6, more preferably 1 to 4, and further preferably 1 to 2, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
Examples of the cycloalkenylalkyl group having 4 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a cyclopropenylmethyl group, a cyclopropenylethyl group, a cyclopropenylpropyl group, a cyclopropenylbutyl group, a cyclobutenylmethyl group, a cyclopentenylmethyl group, a cyclopentenylethyl group, a cyclopentenylpropyl group, a cyclohexenylmethyl group, a cyclohexenylethyl group, and a cyclohexenylpropyl group.
The cycloalkenylalkyl group is a group represented by the following general formula (c2), and is a group including an alkyl group, one hydrogen atom of which is substituted by a cycloalkenyl group.
In the general formula (c2), the circle represents a cycloalkenyl group, R32 represents an alkylene group, and the wavy line represents a bonding site to the carbon atom in the general formula (b1).
The expression “having 4 to 15 carbon atoms” in the “cycloalkenylalkyl group having 4 to 15 carbon atoms” means the total number of carbon atoms of the number of ring carbon atoms of the cycloalkenyl group and the number of carbon atoms of the alkylene group (R32).
The number of carbon atoms (i.e., the number of ring carbon atoms) of the cycloalkenyl group constituting the cycloalkenylalkyl group is preferably 5 to 10, and more preferably 5 to 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
The number of carbon atoms of the alkylene group constituting the cycloalkenylalkyl group is preferably 1 to 6, more preferably 1 to 4, and further preferably 1 to 2, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
Examples of the aryl group having 6 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a phenyl group, a biphenylyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, and an anthryl group.
The expression “having 6 to 15 carbon atoms” in the “aryl group having 6 to 15 carbon atoms” means “6 to 15 ring carbon atoms”.
The number of carbon atoms of the aryl group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
Examples of the arylalkyl group having 7 to 15 carbon atoms that can be selected as the hydrocarbon group (X1) include a phenylmethyl group, a phenylethyl group, a phenylpropyl group, a biphenylylmethyl group, a biphenylylethyl group, a biphenylylpropyl group, a naphthylmethyl group, a naphthylethyl group, a naphthylpropyl group, a phenanthrylmethyl group, a fluorenylmethyl group, a fluorenylethyl group, and an anthrylmethyl group.
The arylalkyl group is a group represented by the following general formula (c3), and is a group including an alkyl group, one hydrogen atom of which is substituted by an aryl group.
In the general formula (c3), the double circle represents an aryl group, R33 represents an alkylene group, and the wavy line represents a bonding site to the carbon atom in the general formula (b1).
The expression “having 7 to 15 carbon atoms” in the “arylalkyl group having 7 to 15 carbon atoms” means the total number of carbon atoms of the number of ring carbon atoms of the aryl group and the number of carbon atoms of the alkylene group (R33)
The number of carbon atoms (i.e., the number of ring carbon atoms) of the aryl group constituting the arylalkyl group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
The number of carbon atoms of the alkylene group constituting the arylalkyl group is preferably 1 to 6, more preferably 1 to 4, and further preferably 1 to 2, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
The hydrocarbon group (X1) is preferably an aryl group having 6 to 15 carbon atoms having at least a hydroxy group. Specifically, the sulfide compound (B1) preferably contains a compound represented by the following general formula (b1-1). The compound represented by the general formula (b1-1) can readily improve the brightness by the combination with the carboxylic acid-based compound (C).
From this standpoint, the content of the compound represented by the general formula (b1-1) is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, and still further preferably 95% by mass to 100% by mass, based on the total amount of the sulfide compound (B1).
In the general formula (b1-1), R15 and R16 each independently represent an alkyl group having 1 to 10 carbon atoms.
The alkyl group is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms, from the standpoint of further facilitating the enhancement of the oxidation stability of the heat treating oil composition. The number of carbon atoms of the branched alkyl group is preferably 4 to 8, more preferably 4 to 6, and further preferably 4.
In the general formula (b1-1), m1 represents an integer of 0 to 4. m1 preferably represents 1 to 3, and more preferably 2.
In the case where m1 represents 2 or more, multiple groups represented by R15 may be the same as or different from each other.
In the general formula (b1-1), m2 represents an integer of 0 to 4. m2 preferably represents 1 to 3, and more preferably 2.
In the case where m2 represents 2 or more, multiple groups represented by R16 may be the same as or different from each other.
In the general formula (b1-1), the hydroxy group is preferably positioned at the 4-position of the phenyl group. m1 and m2 each preferably represent 2, and two groups represented by R15 and two groups represented by R16 each are preferably positioned at the 3-position and the 5-position of the phenyl group, respectively. The two groups represented by R15 and the two groups represented by R16 each are preferably a branched alkyl group having 3 to 10 carbon atoms.
The number of carbon atoms of the branched alkyl group is preferably 4 to 8, more preferably 4 to 6, and further preferably 4.
Specific examples of the sulfide compound (B1) include bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide and 2-ethylthiomethylphenol. Among these, bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide is preferred.
One kind of the sulfide compound (B1) may be used alone, or two or more kinds thereof may be used in combination.
The sulfide compound (B2) is a compound represented by the following general formula (b2).
In the general formula (b2), Ar12 represents an arylene group having 6 to 15 carbon atoms having at least a hydroxy group.
A structure having a sulfur atom and an arylene group bonded via a methylene group, as in the compound represented by the general formula (b2), tends to have an inferior effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) can improve the brightness of a metal material after a heat treatment, such as quenching.
In the case where the number of carbon atoms of the arylene group exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
In the general formula (b2), examples of the arylene group having 6 to 15 carbon atoms constituting Ar12 include a phenylene group, a biphenyldiyl group, a naphthylene group, a phenanthrylene group, a fluorenylene group, and an anthrylene group.
The expression “having 6 to 15 carbon atoms” in the “arylene group having 6 to 15 carbon atoms” means “6 to 15 ring carbon atoms”.
The number of carbon atoms of the arylene group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
In the general formula (b2), the arylene group having 6 to 15 carbon atoms constituting Ar12 has at least one or more hydroxy groups. In the case where the arylene group does not have a hydroxy group, there is a concern that the oxidation stability of the heat treating oil composition is insufficient.
The arylene group may further have a substituent other than a hydroxy group, or may not have a substituent other than a hydroxy group.
Examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, a carboxy group, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 1 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
The number of the hydroxy group of the arylene group may be one, or multiple hydroxy groups may exist, and the number thereof is preferably one.
In the case where the arylene group has a substituent other than a hydroxy group, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
In the general formula (b2), R12 and R13 each independently represent a substituted or unsubstituted hydrocarbon group (X2).
In the case where the hydrocarbon group (X2) has a substituent, examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, a carboxy group, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
In the case where the hydrocarbon group (X2) has a substituent, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
In the general formula (b2), the hydrocarbon group (X2) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms. The number of carbon atoms of the hydrocarbon group (X2) does not include the number of carbon atoms of the substituent that the hydrocarbon group (X2) may have.
In the case where the number of carbon atoms of the group that can be selected as the hydrocarbon group (X2) exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
Examples of the alkyl group having 1 to 15 carbon atoms, the alkenyl group having 1 to 15 carbon atoms, the cycloalkyl group having 3 to 15 carbon atoms, the cycloalkenyl group having 3 to 15 carbon atoms, the cycloalkylalkyl group having 4 to 15 carbon atoms, the cycloalkenylalkyl group having 4 to 15 carbon atoms, the aryl group having 6 to 15 carbon atoms, and the arylalkyl group having 7 to 15 carbon atoms that can be selected as the hydrocarbon group (X2) include the alkyl group having 1 to 15 carbon atoms, the alkenyl group having 1 to 15 carbon atoms, the cycloalkyl group having 3 to 15 carbon atoms, the cycloalkenyl group having 3 to 15 carbon atoms, the cycloalkylalkyl group having 4 to 15 carbon atoms, the cycloalkenylalkyl group having 4 to 15 carbon atoms, the aryl group having 6 to 15 carbon atoms, and the arylalkyl group having 7 to 15 carbon atoms having been exemplified as the hydrocarbon group (X1) above. The preferred ranges of the groups are also the same as in the hydrocarbon group (X1) above.
The sulfide compound (B2) preferably contains a compound represented by the following general formula (b2-1). The compound represented by the general formula (b2-1) can readily improve the brightness by the combination with the carboxylic acid-based compound (C).
From this standpoint, the content of the compound represented by the general formula (b2-1) is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, and still further preferably 95% by mass to 100% by mass, based on the total amount of the sulfide compound (B2).
In the general formula (b2-1), R17 each independently represents a linear or branched alkyl group having 1 to 10 carbon atoms.
The alkyl group is preferably a linear or branched alkyl group having 1 to 6 carbon atoms, and more preferably a linear alkyl group having 1 to 3 carbon atoms, from the standpoint of further facilitating the enhancement of the oxidation stability of the heat treating oil composition.
In the general formula (b2-1), m3 represents an integer of 0 to 3. m3 preferably represents 1 to 2, and more preferably 1.
In the case where m3 represents 2 or more, multiple groups represented by R15 may be the same as or different from each other.
In the general formula (b2-1), R12 and R13 each independently represent a substituted or unsubstituted hydrocarbon group (X2). Examples of the hydrocarbon group (X2) include the same groups as exemplified in the description for the general formula (b2), in which an unsubstituted hydrocarbon group (X2) is preferred, and an unsubstituted alkyl group having 1 to 15 carbon atoms is more preferred.
The number of carbon atoms of the alkyl group is preferably 6 to 15, and more preferably 6 to 14.
The alkyl group may be linear, or may be branched, and is preferably linear.
In the general formula (b2-1), the hydroxy group is preferably positioned at the 1-position of the phenylene group. m3 preferably represents 1, and the group represented by R17 is preferably positioned at the 2-position of the phenylene group. R17 preferably represents a linear alkyl group having 1 to 3 carbon atoms.
Specific examples of the sulfide compound (B2) include 2-methyl-4,6-bis[(n-dodecylthio)methyl]phenol and 2-methyl-4,6-bis[(n-octylthio)methyl]phenol.
One kind of the sulfide compound (B2) may be used alone, or two or more kinds thereof may be used in combination.
The sulfide compound (B3) is a compound represented by the following general formula (b3).
In the general formula (b3), Ar13 represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group, and Ar14 represents a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
A structure having a sulfur atom and an aryl group directly bonded to each other and two sulfur atoms bonded via one carbon atom, as in the compound represented by the general formula (b3), tends to have an inferior effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) can improve the brightness of a metal material after a heat treatment, such as quenching.
In the case where the number of carbon atoms of the aryl group exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
In the general formula (b3), examples of the group represented by Ar13 include the same groups as in Ar11 described in the general formula (b1), and the preferred ranges thereof are also the same as in Ar11.
In the general formula (b3), examples of the aryl group having 6 to 15 carbon atoms constituting Ar14 include a phenyl group, a biphenylyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, and an anthryl group.
The expression “having 6 to 15 carbon atoms” in the “aryl group having 6 to 15 carbon atoms” means “6 to 15 ring carbon atoms”.
The number of carbon atoms of the aryl group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
In the case where the aryl group has a substituent, examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, an amide group, a benzamide group, a carboxy group, a residual group obtained by removing one hydrogen atom from a hydroxy group of a dicarboxylic acid, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
In the case where the aryl group has a substituent, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
The sulfide compound (B3) preferably contains a compound represented by the following general formula (b3-1). The compound represented by the general formula (b3-1) can readily improve the brightness by the combination with the carboxylic acid-based compound (C).
From this standpoint, the content of the compound represented by the general formula (b3-1) is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, further preferably 90% by mass to 100% by mass, and still further preferably 95% by mass to 100% by mass, based on the total amount of the sulfide compound (B3).
In the general formula (b3-1), R18 and R19 each independently represents an alkyl group having 1 to 10 carbon atoms.
The alkyl group is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms, from the standpoint of further facilitating the enhancement of the oxidation stability of the heat treating oil composition. The number of carbon atoms of the branched alkyl group is preferably 4 to 8, more preferably 4 to 6, and further preferably 4.
In the general formula (b3-1), m4 represents an integer of 0 to 4. m4 preferably represents 1 to 3, and more preferably 2.
In the case where m4 represents 2 or more, multiple groups represented by R18 may be the same as or different from each other.
In the general formula (b3-1), m5 represents an integer of 0 to 4. m5 preferably represents 1 to 3, and more preferably 2.
In the case where m5 represents 2 or more, multiple groups represented by R19 may be the same as or different from each other.
In the general formula (b3-1), the hydroxy group is preferably positioned at the 4-position of the phenyl group. m4 and m5 each are preferably 2, and two groups represented by R18 and two groups represented by R19 each are preferably positioned at the 3-position and the 5-position of the phenyl group, respectively. The two groups represented by R18 and the two groups represented by R19 each are preferably a branched alkyl group having 3 to 10 carbon atoms.
The number of carbon atoms of the branched alkyl group is preferably 4 to 8, more preferably 4 to 6, and further preferably 4.
Specific examples of the sulfide compound (B3) include 4,4′-[propan-2,2-diylbis(sulfandiyl)]bis[2,6-bis(1,1-dimethylethyl)phenol] (probucol) and 4-[4-[2-(4-hydroxy-3,5-di-tert-butylphenyl)sulfanylpropan-2-ylsulfanyl]-2,6-di-tert-butylphenoxy]-4-oxo-butanoic acid (succinobucol). Among these, 4,4′-[propan-2,2-diylbis(sulfandiyl)]bis[2,6-bis(1,1-dimethylethyl)phenol] (probucol) is preferred.
One kind of the sulfide compound (B3) may be used alone, or two or more kinds thereof may be used in combination.
The sulfide compound (B4) is a compound represented by the following general formula (b4).
Ar15—S—S—Ar16 (b4)
In the general formula (b4), Ar15 and Ar16 each independently represent a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
A structure having a sulfur atom and an aryl group directly bonded to each other and two sulfur atoms directly bonded to each other, as in the compound represented by the general formula (b4), tends to have an inferior effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) can improve the brightness of a metal material after a heat treatment, such as quenching.
In the case where the number of carbon atoms of the aryl group exceeds 15, the brightness of a metal material after a heat treatment, such as quenching, cannot be improved in some cases even by combining with the carboxylic acid-based compound (C).
In the general formula (b4), examples of the aryl group having 6 to 15 carbon atoms constituting Ar15 and Ar16 include a phenyl group, a biphenylyl group, a naphthyl group, a phenanthryl group, a fluorenyl group, and an anthryl group.
The expression “having 6 to 15 carbon atoms” in the “aryl group having 6 to 15 carbon atoms” means “6 to 15 ring carbon atoms”.
The number of carbon atoms of the aryl group is preferably 6 to 10, and more preferably 6, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
In the case where the aryl group has a substituent, examples of the substituent include a monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, an amino group, a nitro group, an amide group, a benzamide group, a carboxy group, a residual group obtained by removing one hydrogen atom from a hydroxy group of a dicarboxylic acid, and a halogen atom.
The monovalent aliphatic hydrocarbon group having 1 to 10 carbon atoms is preferably a linear or branched alkyl group having 3 to 10 carbon atoms, and more preferably a branched alkyl group having 3 to 10 carbon atoms.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, in which a chlorine atom is preferred.
In the case where the aryl group has a substituent, the number of the substituent may be one, or multiple substituents may exist. In the case where multiple substituents exist, the substituents may be the same as or different from each other.
In the general formula (b4), Ar15 and Ar16 each independently preferably represent an unsubstituted aryl group having 6 to 15 carbon atoms or an aryl group having 6 to 15 carbon atoms having at least one or more hydroxy groups, more preferably an unsubstituted aryl group having 6 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms having at least one or more hydroxy groups, further preferably an unsubstituted aryl group having 6 carbon atoms or an aryl group having 6 carbon atoms having at least one or more hydroxy groups, and still further preferably an unsubstituted aryl group having 6 carbon atoms.
Specific examples of the sulfide compound (B4) include diphenyl disulfide, di-p-tolyl disulfide, 4,4′-dithiodianiline, 2,2′-dithiodianiline, 2,2′-dithiobenzoic acid, bis(2-benzamidophenyl)disulfide, and bis(4-hydroxyphenyl)disulfide. Among these, diphenyl disulfide is preferred.
One kind of the sulfide compound (B4) may be used alone, or two or more kinds thereof may be used in combination.
In the heat treating oil composition of the present embodiment, the sulfur compound (B) preferably contains one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1), the sulfide compound (B2) represented by the general formula (b2), and the sulfide compound (B3) represented by the general formula (b3), and more preferably contains one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1) and the sulfide compound (B2) represented by the general formula (b2), from the standpoint of further facilitating the enhancement of the oxidation stability, and the standpoint of further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C).
In the present embodiment, the one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1), the sulfide compound (B2) represented by the general formula (b2), and the sulfide compound (B3) represented by the general formula (b3) encompasses the following embodiments.
Only sulfide compound (B1) represented by the general formula (b1)
Only sulfide compound (B2) represented by the general formula (b2)
Only sulfide compound (B3) represented by the general formula (b3)
Combination of sulfide compound (B1) represented by the general formula (b1) and sulfide compound (B2) represented by the general formula (b2)
Combination of sulfide compound (B1) represented by the general formula (b1) and sulfide compound (B3) represented by the general formula (b3)
Combination of sulfide compound (B2) represented by the general formula (b2) and sulfide compound (B3) represented by the general formula (b3)
Combination of sulfide compound (B1) represented by the general formula (b1), sulfide compound (B2) represented by the general formula (b2), and sulfide compound (B3) represented by the general formula (b3)
In the present embodiment, the one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1) and the sulfide compound (B2) represented by the general formula (b2) encompasses the following embodiments.
Only sulfide compound (B1) represented by the general formula (b1)
Only sulfide compound (B2) represented by the general formula (b2)
Combination of sulfide compound (B1) represented by the general formula (b1) and sulfide compound (B2) represented by the general formula (b2)
The sulfur compound (B) more preferably contains one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1-1), the sulfide compound (B2) represented by the general formula (b2-1), and the sulfide compound (B3) represented by the general formula (b3-1) from the standpoint of still further facilitating the enhancement of the oxidation stability, and the standpoint of still further facilitating the achievement of the effects obtained by the combination with the carboxylic acid-based compound (C). In particular, the sulfur compound (B) more preferably contains one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1-1) and the sulfide compound (B2) represented by the general formula (b2-1) from the standpoint of further enhancing the oxidation stability.
In the present embodiment, the one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1-1), the sulfide compound (B2) represented by the general formula (b2-1), and the sulfide compound (B3) represented by the general formula (b3-1) encompasses the following embodiments.
Only sulfide compound (B1) represented by the general formula (b1-1)
Only sulfide compound (B2) represented by the general formula (b2-1)
Only sulfide compound (B3) represented by the general formula (b3-1)
Combination of sulfide compound (B1) represented by the general formula (b1-1) and sulfide compound (B2) represented by the general formula (b2-1)
Combination of sulfide compound (B1) represented by the general formula (b1-1) and sulfide compound (B3) represented by the general formula (b3-1)
Combination of sulfide compound (B2) represented by the general formula (b2-1) and sulfide compound (B3) represented by the general formula (b3-1)
Combination of sulfide compound (B2) represented by the general formula (b2-1) and sulfide compound (B3) represented by the general formula (b3-1)
Combination of sulfide compound (B1) represented by the general formula (b1-1), sulfide compound (B2) represented by the general formula (b2-1), and sulfide compound (B3) represented by the general formula (b3-1)
In the present embodiment, the one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1-1) and the sulfide compound (B2) represented by the general formula (b2-1) encompasses the following embodiments.
Only sulfide compound (B1) represented by the general formula (b1-1)
Only sulfide compound (B2) represented by the general formula (b2-1)
Combination of sulfide compound (B1) represented by the general formula (b1-1) and sulfide compound (B2) represented by the general formula (b2-1)
In the heat treating oil composition of the present embodiment, the content of the sulfur compound (B) is preferably 0.01% by mass or more, more preferably 0.02% by mass, and further preferably 0.05% by mass or more, from the standpoint of further facilitating the achievement of the effects of the present invention, and is preferably 2.0% by mass or less, more preferably 1.0% by mass or less, and further preferably 0.5% by mass or less, from the standpoint of facilitating the suppression of the formation of sludge and the decrease in lifetime of the heat treating oil composition caused by an excessive amount of the sulfur compound used, all based on the total amount of the heat treating oil composition.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the content thereof is preferably 0.01% by mass to 2.0% by mass, more preferably 0.02% by mass to 1.0% by mass, and further preferably 0.05% by mass to 0.5% by mass.
In the heat treating oil composition of the present embodiment, the molecular weight of the sulfur compound (B) is preferably 100 or more, more preferably 150 or more, and further preferably 180 or more, and is preferably 1,500 or less, more preferably 1,200 or less, and further preferably 1,000 or less, from the standpoint of further facilitating the achievement of the effects of the present invention.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the molecular weight thereof is preferably 100 to 1,500, more preferably 150 to 1,200, and further preferably 180 to 1,000.
The heat treating oil composition of the present embodiment contains a carboxylic acid-based compound (C).
As described above, the sulfur compound (B) is inferior in the effect of improving the brightness of a metal material after a heat treatment, such as quenching. However, the combination use thereof with the carboxylic acid-based compound (C) generates interaction between the sulfur compound (B) and the carboxylic acid-based compound (C), and thereby can improve the brightness of a metal material after a heat treatment, such as quenching.
The carboxylic acid-based compound (C) is one or more kinds selected from the group consisting of a compound having at least one carboxy group, and an anhydride thereof.
The compound having at least one carboxy group may be a monobasic carboxylic acid, or may be a dibasic or higher polybasic carboxylic acid. A partial ester of a polybasic carboxylic acid that is partially esterified may also be used.
Among these, the compound having at least one carboxy group is preferably a dibasic or higher polybasic carboxylic acid, and more preferably a dibasic carboxylic acid, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the sulfur compound (B).
Accordingly, the carboxylic acid-based compound (C) is preferably one or more kinds selected from the group consisting of a dibasic carboxylic acid and an anhydride thereof. Among these, a dibasic carboxylic acid is preferred.
One kind of the carboxylic acid-based compound (C) may be used alone, or two or more kinds thereof may be used in combination.
Examples of the preferred carboxylic acid-based compound (C) include one or more kinds selected from a dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid, and an anhydride thereof. Among these, one or more kinds selected from a dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid, is preferred, and an alkenylsuccinic acid is more preferred, from the standpoint of further facilitating the achievement of the effects obtained by the combination with the sulfur compound (B).
The number of carbon atoms of the alkyl group of the alkylsuccinic acid and the alkenyl group of the alkenylsuccinic acid is preferably 10 to 20.
The 40° C. kinematic viscosity of the dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid (preferably an alkenylsuccinic acid) that is preferably used as the carboxylic acid-based compound (C) is preferably 10 mm2/s or more, more preferably 15 mm2/s or more, and further preferably 20 mm2/s or more, and is preferably 50 mm2/s or less, more preferably 40 mm2/s or less, and further preferably 30 mm2/s or less.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the 40° C. kinematic viscosity thereof is preferably 10 mm2/s to 50 mm2/s, more preferably 15 mm2/s to 40 mm2/s, and further preferably 20 mm2/s to 30 mm2/s.
In the description herein, the 40° C. kinematic viscosity of the dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid (preferably an alkenylsuccinic acid) is a value that is measured according to JIS K2283:2000.
The acid number of the dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid (preferably an alkenylsuccinic acid) that is preferably used as the carboxylic acid-based compound (C) is preferably 50 mgKOH/g or more, more preferably 100 mgKOH/g or more, and further preferably 150 mgKOH/g or more, and is preferably 400 mgKOH/g or less, more preferably 300 mgKOH/g or less, and further preferably 250 mgKOH/g or less.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the acid number thereof is preferably 50 mgKOH/g to 400 mgKOH/g, more preferably 100 mgKOH/g to 300 mgKOH/g, and further preferably 150 mgKOH/g to 250 mgKOH/g.
In the description herein, the acid number of the dibasic carboxylic acid, such as an alkylsuccinic acid and an alkenylsuccinic acid (preferably an alkenylsuccinic acid) is a value that is measured by the indicator titration method according to JIS K2501:2003, Sec. 5.
In the heat treating oil composition of the present embodiment, the content of the carboxylic acid-based compound (C) is preferably 0.1% by mass or more, more preferably 0.15% by mass, and further preferably 0.2% by mass or more, and is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and further preferably 2.0% by mass or less, based on the total amount of the heat treating oil composition, from the standpoint of further facilitating the achievement of the effects of the present invention.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the content thereof is preferably 0.1% by mass to 5.0% by mass, more preferably 0.15% by mass to 3.0% by mass, and further preferably 0.2% by mass to 2.0% by mass.
In the heat treating oil composition of the present embodiment, the content ratio [(B)/(C)] of the sulfur compound (B) and the carboxylic acid-based compound (C) in terms of mass ratio is preferably 0.002 or more, more preferably 0.02 or more, and further preferably 0.1 or more, and is preferably 0.8 or less, more preferably 0.5 or less, and further preferably 0.3 or less, from the standpoint of further facilitating the achievement of the effects of the present invention.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the content ratio is preferably 0.002 to 0.8, more preferably 0.02 to 0.5, and further preferably 0.1 to 0.3.
The heat treating oil composition of the present embodiment can be prepared by mixing the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C), and additives that have been ordinarily used in heat treating oil compositions may be further blended therein depending on necessity. Examples of the additives include a vapor blanket collapse agent, a brightness improver, a coolability improver, and an antioxidant.
One kind of the additives may be used alone, or two or more kinds thereof may be used in combination.
Examples of the vapor blanket collapse agent include an ethylene-α-olefin copolymer (in which the α-olefin has 3 to 20 carbon atoms), such as an ethylene-propylene copolymer; a hydrogenated product of the ethylene-α-olefin copolymer; a polymer of an α-olefin having 5 to 20 carbon atoms, such as 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, and 1-octadecene; a hydrogenated product of the polymer of an α-olefin; a polymer of an olefin having 3 or 4 carbon atoms, such as polypropylene, polybutene, and polyisobutylene; a hydrogenated product of the polymer of the olefin; a polymer compound, such as a polymethacrylate, a polymethacrylate, a polystyrene, and a petroleum resin; and asphalt.
One kind of the vapor blanket collapse agent may be used alone, or two or more kinds thereof may be used in combination.
The number average molecular weight (Mn) of the vapor blanket collapse agent is generally preferably 800 to 100,000. The number average molecular weight (Mn) of the vapor blanket collapse agent is a value that is measured by gel permeation chromatography (GPC) in terms of polystyrene.
The content of the vapor blanket collapse agent is preferably 0.5% by mass to 18% by mass, more preferably 1.0% by mass to 16% by mass, and further preferably 2.0% by mass to 15% by mass, based on the total amount of the heat treating oil composition.
Examples of the brightness improver include fat and oil; a full ester of an alkylsuccinic acid, an alkylsuccinic acid imide, and derivatives thereof; a full ester of an alkenylsuccinic acid, an alkenylsuccinic acid imide, and derivatives thereof; and a substituted hydroxy aromatic carboxylate ester (full ester) and a derivative thereof.
One kind of the brightness improver may be used alone, or two or more kinds thereof may be used in combination.
The content of the brightness improver is preferably 0.1% by mass to 5.0% by mass, more preferably 0.3% by mass to 3.0% by mass, further preferably 0.4% by mass to 2.0% by mass, based on the total amount of the heat treating oil composition.
Examples of the coolability improver include a metal-based detergent, such as a metal sulfonate, a metal salicylate, and a metal phenate.
Examples of the metal constituting the metal-based detergent include an alkali metal, such as sodium and potassium, and an alkaline earth metal, such as magnesium, calcium, and barium.
Examples of the coolability improver also include an imide-based dispersant, such as a boron-containing alkenylsuccinic acid imide compound, and an amide compound of a monobasic or dibasic carboxylic acid, such as a fatty acid and succinic acid.
One kind of the coolability improver may be used alone, or two or more kinds thereof may be used in combination.
The content of the coolability improver is preferably small from the standpoint of further facilitating the achievement of the effects of the present invention. Specifically, the content of the coolability improver is preferably less than 0.20% by mass, more preferably less than 0.10% by mass, further preferably less than 0.01% by mass, and still further preferably less than 0.001% by mass, based on the total amount of the heat treating oil composition, and it is still more further preferred that the coolability improver is not contained.
Examples of the antioxidant include a phenol-based antioxidant and an amine-based antioxidant.
Examples of the phenol-based antioxidant include a monocyclic phenol compound, such as 2,6-di-tert-butyl-p-cresol, 2,6-di-tert-butyl-4-ethylphenol, 2,4,6-tri-tert-butylphenol, 2,6-di-tert-butyl-4-hydroxymethylphenol, 2,6-di-tert-butylphenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butyl-4-(N,N-dimethylaminomethyl)phenol, 2,6-di-tert-amyl-4-methylphenol, and n-octadecyl-3-(4-hydroxy-3,5-di-tert-butylphenyl) propionate; and a polycyclic phenol compound, such as 4,4′-methylenebis(2,6-di-tert-butylphenol), 4,4′-isopropylidenebis(2,6-di-tert-butylphenol), 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 4,4′-bis(2,6-di-tert-butylphenol), 4,4′-bis(2-methyl-6-tert-butylphenol), 2,2′-methylenebis(4-ethyl-6-tert-butylphenol), and 4,4′-butylidenebis(3-methyl-6-tert-butylphenol).
Examples of the amine-based antioxidant include a diphenylamine-based antioxidant and a naphthylamine-based antioxidant.
Examples of the diphenylamine-based antioxidant include an alkylated diphenylamine having an alkyl group having 3 to 20 carbon atoms, and specific examples thereof include diphenylamine, monooctyldiphenylamine, monononyldiphenylamine, 4,4′-dibutyldiphenylamine, 4,4′-dihexyldiphenylamine, 4,4′-dioctyldiphenylamine, 4,4′-dinonyldiphenylamine, tetrabutyldiphenylamine, tetrahexyldiphenylamine, tetraoctyldiphenylamine, and tetranonyldiphenylamine.
Examples of the naphthylamine-based antioxidant include a phenyl-α-naphthylamine substituted by an alkyl group having 3 to 20 carbon atoms, and specific examples thereof include α-naphthylamine, phenyl-α-naphthylamine, butylphenyl-α-naphthylamine, hexylphenyl-α-naphthylamine, octylphenyl-α-naphthylamine, and nonylphenyl-α-naphthylamine.
One kind of the antioxidant may be used alone, or two or more kinds thereof may be used in combination.
The content of the antioxidant is preferably 0.01% by mass to 5.0% by mass, more preferably 0.02% by mass to 3.0% by mass, and further preferably 0.05% by mass to 2.0% by mass, based on the total amount of the oil composition.
The sulfur content of the heat treating oil composition of the present embodiment is preferably 10 ppm by mass or more, more preferably 20 ppm by mass or more, and further preferably 25 ppm by mass or more, and is preferably 10,000 ppm by mass or less, more preferably 7,000 ppm by mass or less, further preferably 5,000 ppm by mass or less, and still further preferably 3,000 ppm by mass or less, based on the total amount of the heat treating oil composition.
The upper limit values and the lower limit values of these numerical ranges may be optionally combined. Specifically, the content thereof is preferably 10 ppm by mass to 10,000 ppm by mass, more preferably 20 ppm by mass to 7,000 ppm by mass, further preferably 25 ppm by mass to 5,000 ppm by mass, and still further preferably 25 ppm by mass to 3,000 ppm by mass.
In the description herein, the content of sulfur in the heat treating oil composition means a value that is measured according to the ultraviolet fluorescence method of JIS K2541-6:2013 for values in the ppm by mass order, and means a value that is measured according to the wavelength dispersion fluorescent X-ray method of JIS K2541-7:2013 for values in the percent by mass order.
The phosphorus amount, the molybdenum amount, and the zinc amount of the heat treating oil composition of the present embodiment each independently are preferably less than 0.01% by mass, and more preferably less than 0.001% by mass, based on the total amount of the heat treatingu oil composition, and it is further preferred that phosphorus, molybdenum, and zinc are not contained.
In the description herein, the phosphorus amount, the molybdenum amount, and the zinc amount of the heat treating oil composition can be measured according to JPI-5S-38-03.
The 40° C. kinematic viscosity of the heat treating oil composition of the present embodiment is set corresponding to the target oil temperature in a heat treatment, such as quenching.
A heat treating oil composition is classified into a cold oil used at a low oil temperature, a hot oil used at a high oil temperature, and a semi-hot oil used at an oil temperature therebetween. The cold oil is classified into Type 1 of JIS K2242:2012, and the semi-hot oil and the hot oil are classified into Type 2 of JIS K2242:2012.
In the case where the heat oil composition of the present embodiment is used as a cold oil, the 40° C. kinematic viscosity thereof is preferably 5 mm2/s or more and less than 40 mm2/s.
In the case where the heat treating oil composition of the present embodiment is used as a semi-hot oil or a hot oil, the 40° C. kinematic viscosity thereof is more preferably 40 mm2/s or more and 500 mm2/s or less.
In the description herein, the 40° C. kinematic viscosity of the heat treating oil composition means a value that is measured according to JIS K2283:2000.
The method of producing the heat treating oil composition of the present embodiment is not particularly limited.
For example, the method of producing a heat treating oil composition of the present embodiment includes a step of mixing one or more kinds of a base oil (A) selected from the group consisting of a mineral oil (A1), a synthetic oil (A2), and a vegetable oil (A3), a sulfur compound (B), and a carboxylic acid-based compound (C).
The sulfur compound (B) contains one or more kinds selected from the group consisting of a sulfide compound (B1) represented by the following general formula (b1), a sulfide compound (B2) represented by the following general formula (b2), a sulfide compound (B3) represented by the following general formula (b3), and a sulfide compound (B4) represented by the following general formula (b4).
The carboxylic acid-based compound (C) is one or more kinds selected from the group consisting of a compound having at least one carboxy group, and an anhydride thereof
In the general formula (b1), Ar11 each independently represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group, and R11 represents a substituted or unsubstituted hydrocarbon group (X1), in which the hydrocarbon group (X1) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms.
In the general formula (b2), Ar12 represents an arylene group having 6 to 15 carbon atoms having at least a hydroxy group, and R12 and R13 each independently represent a substituted or unsubstituted hydrocarbon group (X2), in which the hydrocarbon group (X2) is an alkyl group having 1 to 15 carbon atoms, an alkenyl group having 1 to 15 carbon atoms, a cycloalkyl group having 3 to 15 carbon atoms, a cycloalkenyl group having 3 to 15 carbon atoms, a cycloalkylalkyl group having 4 to 15 carbon atoms, a cycloalkenylalkyl group having 4 to 15 carbon atoms, an aryl group having 6 to 15 carbon atoms, or an arylalkyl group having 7 to 15 carbon atoms.
In the general formula (b3), Ar13 represents an aryl group having 6 to 15 carbon atoms having at least a hydroxy group, and Ar14 represents a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
In the general formula (b4), Ar15 and Ar16 each independently represent a substituted or unsubstituted aryl group having 6 to 15 carbon atoms.
The method of mixing the components is not particularly limited, and examples thereof include a step of blending the sulfur compound (B) and the carboxylic acid-based compound (C) with the base oil (A). The sulfur compound (B) and the carboxylic acid-based compound (C) may be simultaneously blended with the base oil (A), and may be separately blended therewith. In the case where the heat treating oil composition further contains an additional component (the additives described above) other than the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C), the additional component may be blended simultaneously with the sulfur compound (B) and the carboxylic acid-based compound (C) with the base oil (A), and may be blended separately therefrom. The components each may be blended in the form of a solution (dispersion) by adding a diluent oil or the like. After blending the components, the components are preferably agitated by a known method for dispersing uniformly.
The preferred embodiments of the base oil (A), the sulfur compound (B), and the carboxylic acid-based compound (C) have been described above.
The heat treating oil composition of the present embodiment can be used in a heat treatment, such as quenching, of a metal material, and thereby the brightness of the metal material after the heat treatment, such as quenching, can be improved. For example, the heat treating oil composition can be favorably used as a heat treating oil composition in performing a heat treatment, such as quenching, of various alloy steels, such as a carbon steel, a nickel-manganese steel, a chromium-molybdenum steel, and a manganese steel.
The heat treating oil composition of the present embodiment is also excellent in oxidation stability.
Accordingly, the heat treating oil composition of the present embodiment is preferably used as a heat treatment oil for quenching or the like of a metal material (preferably a quenching oil or a tempering oil). Furthermore, the present embodiment also relates to a method of using a heat treating oil composition, including using the heat treating oil composition of the present embodiment as a heat treatment oil for quenching or the like of a metal material (preferably a quenching oil or a tempering oil). The oil temperature of the heat treating oil composition in the case where the heat treatment is quenching is preferably set to 40° C. to 280° C., more preferably 50° C. to 200° C., and further preferably 60° C. to 150° C. In the case where the heat treatment is tempering, the oil temperature may be further increased, and the upper limit thereof may be, for example, 300° C. The heating temperature of the metal material may be 800° C. or more and 900° C. or less, and may be more than 900° C. and 1,100° C. or less.
The present invention provides embodiments of the following items [1] to [11].
[1] A heat treating oil composition containing:
in which
[2] The heat treating oil composition according to the item [1], in which in the general formula (b1), the hydrocarbon group (X1) is an aryl group having 6 to 15 carbon atoms having at least a hydroxy group.
[3] The heat treating oil composition according to the item [1] or [2], in which the sulfur compound (B) contains one or more kinds selected from the group consisting of the sulfide compound (B1) represented by the general formula (b1), the sulfide compound (B2) represented by the general formula (b2), and the sulfide compound (B3) represented by the general formula (b3).
[4] The heat treating oil composition according to any one of the items [1] to [3], in which the heat treating oil composition has a sulfur content of 10 ppm by mass to 10,000 ppm by mass based on the total amount of the heat treating oil composition.
[5] The heat treating oil composition according to any one of the items [1] to [4], in which the heat treating oil composition has a content of the sulfur compound (B) of 0.01% by mass to 2.0% by mass based on the total amount of the heat treating oil composition.
[6] The heat treating oil composition according to any one of the items [1] to [5], in which the heat treating oil composition has a content of the carboxylic acid-based compound (C) of 0.1% by mass to 5.0% by mass based on the total amount of the heat treating oil composition.
[7] The heat treating oil composition according to any one of the items [1] to [6], in which the heat treating oil composition has a content ratio [(B)/(C)] of the sulfur compound (B) and the carboxylic acid-based compound (C) in terms of mass ratio of 0.002 to 0.8.
[8] The heat treating oil composition according to any one of the items [1] to [7], in which the heat treating oil composition further contains one or more kinds selected from the group consisting of a vapor blanket collapse agent, an antioxidant, a brightness improver, and a coolability improver.
[9] The heat treating oil composition according to any one of the items [1] to [8], in which the heat treating oil composition is used as a quenching oil or a tempering oil.
[10] A method of using a heat treating oil composition, including using the heat treating oil composition according to any one of the items [1] to [9] as a quenching oil or a tempering oil.
[11] A method for producing a heat treating oil composition, including a step of mixing one or more kinds of a base oil (A) selected from the group consisting of a mineral oil (A1), a synthetic oil (A2) and a vegetable oil (A3), a sulfur compound (B), and a carboxylic acid-based compound (C),
in which
The present invention will be described specifically with reference to examples below, but the present invention is not limited to the following examples.
The base oils (A) and the carboxylic acid-based compounds (C) used in Examples and Comparative Examples and the heat treating oil compositions prepared in Examples and Comparative Examples were measured for the 40° C. kinematic viscosity according to JIS K2283:2000.
The base oils (A) used in Examples and Comparative Examples and the heat treating oil compositions prepared in Examples and Comparative Examples were measured for the sulfur content according to the ultraviolet fluorescence method of JIS K2541-6:2013.
The raw materials used for preparing the heat treating oil compositions of Examples 1 to 8 and Comparative Examples 1 to 9 are shown below.
High viscosity mineral oil classified into Group II of API Category (corresponding to the bright stock having a small sulfur content), sulfur amount: less than 3 ppm by mass, 40° C. kinematic viscosity: 396.7 mm2/s Mineral oil (A1)-2:
Mineral oil classified into Group II of API Category, sulfur amount: less than 3 ppm by mass, 40° C. kinematic viscosity: 7.573 mm2/s Mineral oil (A1)-3:
Mineral oil classified into Group III of API Category, sulfur amount: less than 3 ppm by mass, 40° C. kinematic viscosity: 20.57 mm2/s
Mineral oil classified into Group II of API Category, sulfur amount: less than 3 ppm by mass, 40° C. kinematic viscosity: 31.49 mm2/s
Bis(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide (molecular weight: 470.75) Compound represented by the following chemical formula (b1-1-1)
The compound represented by the chemical formula (b1-1-1) is a compound represented by the general formula (b1-1), in which m1 and m2 represent 2, two groups represented by R15 and two groups represented by R16 all are tert-butyl groups, the hydroxy group is positioned at the 4-position of the phenyl group, and the tert-butyl groups are positioned at the 3-position and the 5-position of the phenyl group.
2-Methyl-4,6-bis[(dodecylthio)methyl]phenol (molecular weight: 536.96)
Compound represented by the following chemical formula (b2-1-1)
The compound represented by the chemical formula (b2-1-1) is a compound represented by the general formula (b2-1), in which m3 represents 1, R17 represents a methyl group, the hydroxy group is positioned at the 1-position of the phenyl group, and the methyl group is positioned at the 2-position of the phenyl group.
Probucol (4,4′-[propan-2,2-diylbis(sulfandiyl)]bis[2,6-bis(1,1-dimethylethyl)phenol], molecular weight: 516.84)
Compound represented by the following chemical formula (b3-1-1)
The compound represented by the chemical formula (b3-1-1) is a compound represented by the general formula (b3-1), in which m4 and m5 represent 2, two groups represented by R18 and two groups represented by R19 all are tert-butyl groups, the hydroxy group is positioned at the 4-position of the phenyl group, and the tert-butyl groups are positioned at the 3-position and the 5-position of the phenyl group.
Diphenyl disulfide (molecular weight: 218.33)
Compound represented by the following chemical formula (b4-1-1)
The compound represented by the chemical formula (b4-1-1) is a compound represented by the general formula (b4), in which Ar15 and Ar16 each represent an unsubstituted phenyl group.
Thiophene compound represented by the following chemical formula (b′)
The acid number is a value that is measured by the indicator titration method according to JIS K2501:2003, Sec. 5.
The base number of calcium sulfonate is a value that is measured by the potentiometric titration method (base number perchloric acid method) according to JIS K2501:2003, Sec. 9.
The raw materials were sufficiently mixed in the blending amounts (% by mass) shown in Tables 1 and 2, so as to prepare the heat treating oil compositions of Examples 1 to 8 and Comparative Examples 1 to 9.
The brightness of the steel material after quenching was evaluated with reference to “Influence of Oxygen in Heat Treating Oils Tank on Brightness (Idemitsu Tribo Review, No. 31, pp. 1963-1966, published on September 30, Heisei 20 (2008))”.
Specifically, a dumbbell specimen of S45C Steel (diameter: 16 mm, length: 30 mm, hardness HRC: 16) and a cylindrical specimen of SUJ2 Steel (diameter: 10 mm, length: 30 mm, hardness HRC: 15) were combined to prepare a test piece. In more detail, the dumbbell specimen of S45C Steel and the cylindrical specimen of SUJ2 Steel were banded by tying with a SUS 303 wire at the center (see
The “S45C Steel” is a carbon steel described in JIS G4051. The “SUJ2 Steel” is a high carbon chromium bearing steel described in JIS G4805. The “SUS 303 wire” is a stainless steel wire described in JIS G4309.
A quenching test was performed in such a manner that the test piece was heated in a furnace having a mixed gas atmosphere of nitrogen and hydrogen, and then the test piece was quenched by placing in the heat treating oil composition.
The conditions of the quenching test were the following two conditions.
The test piece after quenching was evaluated for brightness focusing on the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” based on the following standard. The brightness of the test piece was comprehensively evaluated by the following standard based on the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site”.
An appearance sample having been colored as prescribed was produced, and the color of the quenching test piece was evaluated by visually comparing therewith. The extent of coloration of the appearance sample is shown by the following numerals.
The edge of the test piece (see
The contact site of the test piece (i.e., the contact site of the dumbbell steel specimen and the cylindrical steel specimen, see
The comprehensive evaluation was performed by using the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” based on the following standard.
Evaluation S: The sum of the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” was 0.
Evaluation A: The sum of the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” was 1.
Evaluation B: The sum of the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” was 2.
Evaluation C: The sum of the evaluation results of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” was 3 or more.
In the case where the evaluation result of any one of the “coloration degree”, the “coloration at edge”, and the “coloration at contact site” was 2 or more, the evaluation was designated as C.
The heat treating oil composition of the evaluation S is significantly excellent in brightness. The heat treating oil composition of the evaluation A is excellent in brightness. The heat treating oil composition of the evaluation B is slightly inferior in brightness. The heat treating oil composition of the evaluation C is inferior in brightness.
The heat treating oil composition was subjected to oxidative degradation in the following manner with reference to JIS K2242:2012, “6.3 Stability Test Method”.
400 mL of the heat treating oil was charged in a container having a capacity of 730 mL (45 mm in diameter×500 mm in length) with no catalyst charged therein, and subjected to oxidative degradation at a temperature of 170° C. and an air flow rate of 10 L/hour for 24 hours.
The heat treating oil composition that was not subjected to oxidative degradation (which may be hereinafter referred to as a “new oil”) and the heat treating oil composition after subjecting to the oxidative degradation were measured for the 40° C. kinematic viscosity, and the increment rate of the 40° C. kinematic viscosity after the oxidative degradation (i.e., the increment rate of 40° C. kinematic viscosity from the new oil) was calculated according to the following expression.
(Increment rate of 40° C. kinematic viscosity from new oil)=[(40° C. kinematic viscosity of oil after oxidative degradation)−(40° C. kinematic viscosity of new oil)]/(40° C. kinematic viscosity of new oil)
A larger increment rate of 40° C. kinematic viscosity from the new oil means that the oxidative degradation of the heat treating oil composition more likely proceeds, and in other words, means that the heat treating oil composition has lower oxidation stability. In contrast, a smaller increment rate of 40° C. kinematic viscosity from the new oil means that the oxidative degradation of the heat treating oil composition less likely proceeds, and in other words, means that the heat treating oil composition has higher oxidation stability.
Table 1 shows the results of the evaluation of the brightness for the heat treating oil compositions of Examples 1 to 4 and Comparative Examples 1 to 7.
Table 2 shows the results of the measurement of the 40° C. kinematic viscosity for the heat treating oil compositions of Examples 5 to 8 and Comparative Examples 8 and 9. Table 2 shows the results of the new oils and the results of the oil after subjecting to the 24-hour oxidative degradation test for the heat treating oil compositions.
In Tables 1 and 2, “>” means “less than”.
The following matters are understood from Table 1.
It is understood from the results shown by Examples 1 to 4 that the combination use of the carboxylic acid-based compound (C) with the sulfide compound (B1), (B2), (B3), or (B4) can provide the heat treating oil composition that is excellent in brightness of the test piece after quenching.
On the other hand, it is understood that the use of the carboxylic acid-based compound (C) alone as in Comparative Example 2 and the use of the sulfide compound (B1), (B2), (B3), or (B4) alone as in Comparative Examples 3 to 6 provide the heat treating oil composition that is inferior in brightness of the test piece after quenching.
It is also understood that Comparative Example 7 using calcium sulfonate instead of the carboxylic acid-based compound (C) provides the heat treating oil composition that is inferior in brightness of the test piece after quenching.
The following matters are understood from Table 2.
It is understood from the results shown by Examples 5 to 8 that the combination use of the carboxylic acid-based compound (C) with the sulfide compound (B1), (B2), (B3), or (B4) can provide the heat treating oil composition that is excellent in brightness of the test piece after quenching, and furthermore can prevent the oxidative degradation of the heat treating oil composition from proceeding, so as to enhance the oxidation stability of the heat treating oil composition.
On the other hand, it is understood that the use of the thiophene compound as the sulfur compound in combination with the carboxylic acid-based compound (C) as in Comparative Example 9 can provide excellent brightness of the test piece after quenching, but the oxidative degradation of the heat treating oil composition tends to proceed to fail to provide sufficient oxidation stability of the heat treating oil composition.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-126020 | Jul 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/029228 | 7/29/2022 | WO |
