JPS6123238B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel lubricating oil for cold rolling of metal materials, and its purpose is to prevent the occurrence of poor lubricating activity and surface cleanliness during rolling of metal materials, and to improve lubricating activity and emulsion stability. It is an object of the present invention to provide a lubricating oil which has excellent properties and is free from the risk of generating oil stain even if the cleaning step is omitted and subsequent annealing is performed. In recent years, in cold rolling, there has been a tendency to use mill-clean rolling oil for the purpose of omitting the cleaning process. The important characteristics required of this mill-clean rolling oil are (i) the ability to obtain beautiful surface quality without staining the plate surface due to carbon components in the rolling oil during annealing (annealing stain resistance or mill-clean resistance); and (ii) good lubricity during rolling, and no seizure phenomenon called heat streak or vibration phenomenon called chattering (referred to as lubricity). In order to improve the annealing stain resistance (mill cleanliness) in (i), the addition of fatty acids, oils and organic polymer compounds that tend to cause residual carbon during annealing to the rolling oil is reduced as much as possible. Currently, rolling oils are used whose main components are compounds with structures that easily volatilize or decompose, such as mineral oils and synthetic esters. However, such rolling oil has poor adsorption to the material and weak ability to form an oil film within the roll contact arc, resulting in essentially poor lubricity. In order to improve the lubricity of (ii), oils, fatty acids, etc., as typified by beef tallow-based rolling oil, must be used extensively, which, contrary to the above, results in poor burnout resistance. Mill-clean rolling oil, which aims to eliminate the cleaning process, requires these two contradictory properties, so the mill-clean rolling oil that is currently in practical use has a relatively thick finished plate thickness.
Sheet gauge materials with less stringent rolling conditions (e.g.
It is only applied to plates with a thickness of approximately 0.8 mm or more. In addition, when using rolling oil for a long period of time, the rolling oil emulsion during circulation deteriorates over time and its lubricating properties deteriorate, and fines and iron powder from rolls and rolled materials, deteriorated rolling oil and There is also the problem that the mill cleanliness of the rolling oil is deteriorated due to contamination with rolling mill bearing oil and the like and an increase in iron soap in the oil. Therefore, the present inventor conducted intensive research to overcome the drawbacks of conventional cold rolling oils and provide a lubricating oil for cold rolling that meets the requirements (i) and (ii) above.
Predetermined amounts of monoesters obtained from aliphatic carboxylic acids and aliphatic alcohols, dimer acids and/or
or in combination with a predetermined amount of polymeric acid as a base oil,
A composition that is made by adding a predetermined amount of esterified 1/2 or more of the terminal hydroxyl groups of the ethylene oxide adduct of a specific polyhydric alcohol with an aliphatic carboxylic acid is a composition that does not generate oil stains and is resistant to annealing stains. It has excellent oil (milk cleanliness) properties, has excellent lubricity without any particular reduction in lubricity, and also exhibits good emulsion stability over a long period of time when recycled in an emulsified state, and has excellent heat resistance. They discovered that it has oxidative stability and completed the first invention. That is, the first invention comprises (1) 40 to 95% by weight of monoesters of aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms, and (2) 16 carbon atoms.
0.5 to 20% by weight of at least one type of dimer acid or polymer acid of ~20 higher aliphatic unsaturated acids is used as a base oil, and (3) ethylene is added to the active hydrogen atom of a polyhydric alcohol having 2 to 6 hydroxyl groups. Oxide is 3
2 to 40% by weight of a compound having a structure in which 20 moles or more of the terminal hydroxyl groups of the adduct are esterified with an aliphatic carboxylic acid having 8 to 18 carbon atoms.
The present invention provides a blended lubricating oil for cold rolling. Monoesters used as the base oil component in the present invention include monoesters of aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms, such as methyl stearate, methyl behenate, butyl stearate, Octyl stearate, lauryl stearate, methyl oleate, octyl oleate, decyl oleate, lauryl oleate, methyl palmitate, butyl palmitate, methyl ester of beef tallow fatty acid, octyl ester of beef tallow fatty acid, lauryl ester of beef tallow fatty acid , methyl ester of palm oil fatty acid, octyl ester of palm oil fatty acid, octyl ester of coconut oil fatty acid, lauryl ester of coconut oil fatty acid, and the like. These esters have mill-clean properties superior to mineral oils that are normally used as base oils for mill-clean rolling oils, and also superior lubricity to mineral oils. If the number of carbon atoms in the aliphatic carboxylic acid used in the ester is greater than 22 and the number of carbon atoms in the aliphatic alcohol is greater than 12, the amount of oil stain generated will increase, and the number of carbon atoms in the aliphatic carboxylic acid is smaller than 12. In this case, the lubricity decreases. These esters are used in an amount of 40 to 95% by weight (hereinafter simply referred to as %) in the total composition. If this exceeds 95%, the blending ratio of dimer acid or polymeric acid, etc. will decrease, resulting in a decrease in lubricity, and if it is less than 40%, the contribution rate as a low oil stain ester in the base oil will decrease.
This is not preferable since it is difficult to achieve its effect. In the present invention, it is necessary to add dimer acid and/or polymer acid to the above-mentioned monoesters to form a base oil, and by blending these, the lubricity is equivalent to or better than that of ordinary beef tallow rolling oil. Even if rolling oil remains on the surface of the steel plate after rolling, it has the property of not producing any oil stains during subsequent annealing, so it prevents the deterioration of lubricity and actively improves lubricity. It was even possible to improve it. Dimer and polymer acids have 16 to 20 carbon atoms
Dimer acids or polymer acids such as higher aliphatic monoenoic acids or dienoic acids, such as dimer acids and polymer acids such as zomarinic acid, oleic acid, linoleic acid, and gadolenic acid. These dimer and polymer acids are present in the total composition from 0.5 to 20
Used in a range of %. If it exceeds this range, oil stain will occur significantly, and if it is less than this range, lubricity will decrease, both of which are undesirable. Furthermore, it is necessary to blend the compound (3) into the lubricating oil for cold rolling of the present invention, and by blending this, the rolling oil can be reused stably over a long period of time, and the rolling oil emulsion can be used. Mill cleanliness will not be adversely affected due to deterioration over time and changes in lubrication properties, fine particles of iron powder from rolls or rolling materials, or even mixing into rolling oil such as bearing oil. Characteristics can be given. Here, various known polyhydric alcohols can be used, and examples thereof include ethylene glycol, 1,4-butanediol, glycerin, pentaerythritol, and sorbitol. The number of added moles of ethylene oxide is 3
-20 mol is preferable, and if it is less than 3 mol, the HLB (hydrophilicity-oleophilicity balance) will be small, the dispersibility in water will be poor, and the oil stain after annealing of the rolling oil attached to the steel plate will be reduced. The amount generated increases. Also, when the number of added moles is greater than 20,
HLB becomes large, and the stability of emulsification or dispersion in water is too good, resulting in less oil adhering to the steel plate during rolling, poor lubricity, and poor thermal stability and rolling oil composition. Solubility deteriorates. As the aliphatic carboxylic acid having 8 to 18 carbon atoms, both natural products and synthetic products can be used, and it is necessary that 1/2 or more of the terminal hydroxyl groups are esterified with the carboxylic acid. . When the esterification rate is lower than 1/2, the lubricity, thermal stability, and solubility in the rolling oil composition decrease, which is not preferable. It is preferable that the compound (3) be blended in an amount of 2 to 40% in the total composition; otherwise, it will be difficult to maintain the stability of the rolling oil emulsion over a long period of time, and if it exceeds 40%, Scum generated during circulation of rolling oil, fine iron powder from rolls and rolling materials, and dirt from bearing oil are stably incorporated into the rolling oil emulsion, which is undesirable since it adversely affects mill cleanliness. Although the object of the present invention is fully achieved by the first invention in which the above (1) to (3) are blended, if a predetermined amount of oil or fat is further blended into the base oil of the first invention, ,
In addition to the characteristics of the first invention, we have discovered that the lubricity can be further improved, or that the amount of expensive dimer acid and polymer acid can be reduced while maintaining the same level of lubricity. Completed the invention. That is, the second invention consists of (1) 40 to 90% by weight of monoesters of aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms; (2) 16 carbon atoms;
0.5 to 10% by weight of at least one dimer acid or polymeric acid of ~20 higher aliphatic unsaturated acids; and (4)
5 to 40% by weight of fats and oils is used as a base oil, and to this (3) 3 to 20 moles of ethylene oxide is added to the active hydrogen atom of a polyhydric alcohol having 2 to 6 hydroxyl groups, and an aliphatic compound having 8 to 18 carbon atoms is added. The present invention provides a lubricating oil for cold rolling containing 2 to 25% by weight of a compound having a structure in which 1/2 or more of the terminal hydroxyl groups of the adduct are esterified with carboxylic acid. In the second invention, the fats and oils (4) to be blended with the base oil include natural animal and vegetable fats and oils such as beef tallow, lard, palm oil, castor oil, and soybean oil, which may be used alone or in combination of two or more. Used as a mixture. These oils and fats usually contain impurities and mixed contaminants, including SNP, which promotes the generation of oil stains, so in the case of crude oils and fats, those that have been purified by centrifugal desludging and white clay treatment are recommended. It is preferable to use These oils and fats are 5 in the total composition.
It is blended so that it is ~40%. If it exceeds 40%, oil stain will occur significantly, and if it is less than 5%, the lubricity will deteriorate, which is not preferable. Other components (1) to (3) in the second invention are all the same as those in the first invention, and their blending amounts are:
Preferably, the monoesters (1) are in the range of 40 to 90%, the dimer acids and/or polymer acids in (2) are in the range of 0.5 to 10%, and the compounds in (3) are in the range of 2 to 25%. , outside this range, problems as described in the first invention occur. In addition to the above-mentioned essential components, the lubricating oil for cold rolling of the present invention may contain various known additives, such as oiliness improvers, extreme pressure additives, rust preventives, antioxidants, etc., as necessary. can do. The lubricating oil for cold rolling of the present invention can be produced, for example, by heating and mixing monoesters, dimer acids or polymer acids, and fats and oils in a predetermined proportion to 50 to 60°C, and adding the compound (3) above to this mixture. In addition, an antioxidant, an oiliness improver, and other various additives are added as required, and the mixture is uniformly mixed. The lubricating oil for cold rolling of the present invention as described above has performance equivalent to or better than conventionally commercially available tallow-based rolling oils in terms of lubricity, and has better mill cleanliness than conventionally commercially available mineral oil-based rolling oils. It is equivalent to oil, has excellent emulsified state stability after long-term use, and can also perform mill-clean rolling on thin materials, which was previously only possible for thick to medium-weight materials. It has the following advantages. Next, the features of the lubricating oil for cold rolling of the present invention will be explained using examples. Example 1 Lubricating oil (i) First invention No. 1 Methyl tallow fatty acid 92 (wt%) Ester Polymerized acid (3) 2 Emulsifier (1) 4 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure Additive No. 2 Methyl 80 ester of beef tallow fatty acid Polymerized acid (5) 10 Emulsifier (2) 8 Phenolic oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No. 3 60 Methyl ester of palm oil fatty acid Polymerized acid ( 1) 18 Emulsifier (3) 20 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No. 4 Methyl stearate 50 Polymerization acid (4) 20 Emulsifier (4) 28 Phenol oxidation 1 Inhibitor Phosphate ester System 1 Extreme pressure additive (ii) Second invention No. 5 Butyl stearate 61 Beef tallow (2) 30 Polymerized acid (1) 2 Emulsifier (1) 5 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure Additive No. 6 Octyl palmitate 52 Palm oil (1) 20 Polymerized acid (2) 4 Emulsifier (2) 3 Phenolic oxidation 1 Inhibitor No.7 68 Lauryl ester of coconut oil fatty acid Tallow (1) 5 Polymerized acid ( 3) 5 Emulsifier (3) 20 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No. 8 Methyl of beef tallow fatty acid 74 Ester Castor oil 5 Polymerized acid (4) 10 Emulsifier (4) 10 Phenol oxidation 1 Prevention Agent No. 9 Palm oil fatty acid 74 ethyl ester Pork fat 20 Polymerized acid (5) 2 Emulsifier (5) 2 Phenolic oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No.10 Methylpehenate 81 Soybean oil 10 Polymerized acid (3) 4 Emulsifier (6) 5 No.11 Octyl oleate 55.5 Palm oil (2) 40 Polymerized acid (2) 0.5 Emulsifier (7) 3 Phenolic oxidation 1 Inhibitor No.12 Lauryl myristate 62 Beef tallow (2) 30 Polymerized acid (1) 3 Emulsifier (8) 5 No.13 Methyl stearate 66 Castor oil 5 Polymerized acid (1) 3 Emulsifier (4) 25 Phenolic oxidation 1 Inhibitor (ii) Comparative product No.1 Palm oil fatty acid 96 Methyl ester Polymerizing acid (2) 1 Emulsifier (1) 1 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No. 3 Methyl of tallow fatty acid 34 Ester Polymerizing acid (3) 41 Emulsifier (9) 23 Phenol Oxidation system 1 Inhibitor Phosphate ester type 1 Extreme pressure additive No. 4 Beef tallow (2) 94 Polymerized acid (1) 2 Emulsifier (1) 2 Phenol oxidation 1 Inhibitor Phosphate ester type 1 Extreme pressure additive No. 5 Butyl stearate 61 Beef tallow (2) 30 Beef tallow fatty acid 2 Emulsifier (10) 5 Phenol oxidation 1 Inhibitor Phosphate ester 1 Extreme pressure additive No. 6 Commercial beef tallow rolling oil No. 7 Commercial mineral oil Milclean Rolling oil (Note) Polymerizing acid (1): Polymer acid of oleic acid (dimer acid: Polymer acid higher than trimer acid =
8:2) Polymerization acid (2): Polymer acid of tall oil fatty acid (dimer acid: polymer acid higher than trimer acid = 75:25) Polymerization acid (3): Polymer acid of soybean oil fatty acid (dimer acid: higher than trimer acid) Polymer acid (4): Polymer acid of zomarinic acid, oleic acid, and gadolenic acid (equal ratio of the three components) (dimer acid: polymer acid higher than trimer acid = 9:1) Polymerization acid (5): Heavy acid of oleic acid and linoleic acid (blending ratio oleic acid/linoleic acid = 2/1 weight) (dimer acid: polymerization acid higher than trimer acid = 5:5) Beef tallow (1): Crude beef tallow (saponification value: 197, iodine value: 42) Beef tallow (2): Crude beef tallow is centrifugally desludged and then purified by clay treatment (saponification value: 197, iodine value: 42)
198, iodine value 41) Palm oil (1): Crude palm is centrifugally desludged (saponification value 199, iodine value 45) Palm oil (2): Crude palm is centrifugally desludged, then treated with clay, Alkali-refined (Saponification value 201, Iodine value 45) Castor oil: Saponification value 180, Iodine value 85 Soybean oil: Saponification value 192, Iodine value 121 Pork fat: After centrifuging the crude pork fat and removing the sludge, white clay Processed and purified (saponification value 198,
Iodine value: 51) Emulsifier (1): A structure in which 20 moles of ethylene oxide is added to sorbitol, and three of the six terminal hydroxyl groups of the adduct are esterified with oleic acid Emulsifier (2): Addition of 20 moles of ethylene oxide to sorbitol Emulsifier (3): 10 moles of ethylene oxide is added to pentaerythritol, and all the terminal hydroxyl groups of the adduct are esterified with lauric acid. Emulsifier (4): One with a structure in which 6 moles of ethylene oxide is added to trimethylolethane and two of the three terminal hydroxyl groups of the adduct are esterified with lauric acid. (5): A structure in which 20 moles of ethylene oxide is added to trimethylolpropane, and all the terminal hydroxyl groups of the adduct are esterified with stearic acid.Emulsifier (6): 5 moles of ethylene oxide is added to glycerin, A structure in which two of the three terminal hydroxyl groups of the adduct are esterified with beef fatty acid Emulsifier (7): Glycerin with ethylene oxide
By adding 15 moles and lauric acid,
Emulsifier (8): A structure in which all the terminal hydroxyl groups of polyethylene glycol with a molecular weight of 400 are esterified with oleic acid Emulsifier (9): Ethylene in trimethylolpropane A structure in which 2 moles of oxide is added and one of the three terminal hydroxyl groups of the adduct is esterified with lauric acid Emulsifier (10): Nonionic surfactant...polyoxyethylene (n) nonyl fluoride Enyl ether (average number of added moles n = 7) 2 Test items and test methods (1) Lubricating performance Using a Timken tester, concentration 5%, temperature
A lubricating oil emulsion at 50°C was prepared in advance in a tank and supplied in circulation. The evaluation was carried out by selecting three load levels that approximately corresponded to the rolling pressure during rolling, and investigating the seizure limit rotation speed and friction torque for each. The evaluation was expressed as a ratio of the number of rotations at the limit of seizure, with 1 being the worst. (2) 0.5g/ on the surface of a steel plate sample of appropriate size.
Apply ² m of lubricating oil and stack 40
After pressurizing and adhering to Kg/cm ² , in an air atmosphere.
Leave it at 120℃ for 15 hours, and then add (N ₂ +5%
_H2 ) After annealing at 700°C for 2 hours in an annealing furnace surrounded by a mixed gas, the beauty of the steel plate surface was visually evaluated. Beauty is evaluated on a 5-point scale, with 5 being the worst.
And so. (3) Long-term circulation stability of emulsion A lubricating oil emulsion with a concentration of 5 ^wt % and a temperature of 50°C is prepared in advance in a tank, and then continuously transferred to an iron roll heated to 150°C with a pressure of 2.5 kg/cm ² by a gear pump. After 48 hours of circulating injection, the oil content of the emulsion after removing the oil content floating in the upper layer was extracted and weighed, and the reduction rate with respect to the initial amount of oil charged was determined. In addition, the emulsion stability index was also measured over time.
For ESI, 500 ml of the emulsion collected from the middle layer of the tank was allowed to stand for 10 minutes, and then the ratio of the oil content in the upper layer 100 ml to the oil content in the lower layer 100 ml was calculated. 3 Results Table 1 shows a comparison of lubrication performance, Table 2 shows a comparison of annealing stain resistance, and Table 3 shows the long-term circulation stability of the emulsion.

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Claims (1)

[Scope of Claims] 1 (1) Monoesters of aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms 40
~95% by weight and (2) 0.5 to 20% by weight of at least one type of dimer acid or polymeric acid of higher aliphatic unsaturated acid having 16 to 20 carbon atoms, and (3) 2 to 6 hydroxyl groups as a base oil. A compound having a structure in which 3 to 20 moles of ethylene oxide is added to the active hydrogen atom of a polyhydric alcohol, and 1/2 or more of the terminal hydroxyl groups of the adduct are esterified with an aliphatic carboxylic acid having 8 to 18 carbon atoms. A lubricating oil for cold rolling of metal materials, characterized by containing 2 to 40% by weight of. 2 (1) Monoesters of aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms 40
~95% by weight, and (2) 0.5 to 10% by weight of at least one type of higher aliphatic unsaturated acid dimer acid or polymeric acid having 16 to 20 carbon atoms, and (4) 5 to 40% by weight of oils and fats.
is used as a base oil, 3 to 20 moles of ethylene oxide is added to the active hydrogen atom of (3) a polyhydric alcohol having 2 to 6 hydroxyl groups, and the adduct is added with an aliphatic carboxylic acid having 8 to 18 carbon atoms. 2 to 25 compounds with a structure in which 1/2 or more of the terminal hydroxyl groups are esterified
A lubricating oil for cold rolling of metal materials characterized by containing % by weight.