JP3096289B2 - Water-dispersed steel sheet cold rolling oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention requires that excellent rolling lubricity, sheet surface quality, and resistance to mill contamination are required, and that high-speed rolling improves productivity and eliminates the danger of fire due to accumulated scum. Suitable for use in the target cold rolling mill,
The present invention relates to a water-dispersed cold-rolling oil for a water-dispersed steel sheet.

[0002]

2. Description of the Related Art Cold rolling oil for steel sheets mainly comprises natural oils such as beef tallow and palm oil as lubricating components, and lubricating components such as oiliness improvers and extreme pressure additives, rust preventives, and oxidizing agents. An aqueous emulsion prepared by mixing an inhibitor and the like, further adding an emulsifier and a dispersant, and then mixing with water has been used. In recent years, from the viewpoint of effective utilization of existing production facilities, it has been a major issue for steel makers to improve productivity by achieving high-speed rolling. Although it varies depending on the production line, for example, in a rolling line using a circulation system, it is generally required to perform high-speed rolling of an average rolling speed of a steel sheet of 1700 m / min or more for a soft material and 1500 m / min or more for a hard material. However, conventional cold-rolling oils mainly composed of natural fats and oils are low-cost, but have a large amount of scum, insufficient circulation stability, and insufficient lubricity in high-speed rolling. There were many problems such as that. In addition, when a conventional rolling oil using a solid fat such as beef tallow is used, scum around the mill is often accumulated, which not only deteriorates the working environment but also causes a fire accident. For this reason, rolling using rolling oil that does not use solid fat has been a long-standing problem.

[0003] In this regard, various rolling oils that can be rolled at high speed using liquid base oils that do not solidify at room temperature, particularly synthetic esters, have been proposed. For example, JP-A-6-108079 and JP-A-6-3223 disclose a so-called hindered ester which is an ester of a polyhydric alcohol and a fatty acid.
JP-A-6-2797, which discloses a rolling oil described in JP-A-85-85, and a mixture of a hindered ester and a complex ester.
Rolling oils described in JP-A-78-No. However, these materials cannot be said to have sufficient high-speed rolling properties, and the required performances such as reducing the accumulation of scum around the mill have not yet reached a satisfactory level.

In general, it is well known that lubricating properties are improved by increasing the base oil viscosity of rolling oil (Yasumoto Yamamoto et al., "Plasticity and Processing", 37-422 (1996), 265). However, conventional emulsified rolling oils using surfactants such as nonionic surfactants tend to cause slips and decrease in circulating stability, and conversely reduce productivity. That is the current situation. In this regard, as a rolling oil composition having excellent circulation stability, a rolling oil composition described in JP-B No. 62-14599 is known, but it is not necessarily sufficient for solving the problems of further high-speed rolling and sedimentation scum. Was not. In Japanese Patent Publication No. 3-4600, a milk phosphorus type rolling oil using a synthetic ester and a polymer dispersant is also disclosed. There is no description.

[0005]

SUMMARY OF THE INVENTION The object of the present invention can be achieved by the conventional rolling oil without the problems of an increase in oil cost and a decrease in long-term circulation stability when cold rolling various types of steel sheets. To provide an inexpensive recirculating water-dispersed water-dispersed steel sheet cold-rolling oil that is capable of improving productivity by high-speed rolling that was not available, and is excellent in scum deposition resistance, slip resistance, seizure resistance, etc. It is in.

[0006]

Under such circumstances, the present inventors have conducted intensive studies and have found that (a) mineral oils and / or monoesters, (b) oils and fats, and (c) specific oils and fats. Use of a lubricant for cold rolling oil for water-dispersed steel sheets, which contains a complex ester and exhibits a predetermined kinematic viscosity and pour point, as a rolling oil component, reduces the accumulation of scum around the mill and causes a fire hazard. The present inventors have found that high-speed rolling can be performed without causing poor lubrication such as chattering and heat scratching while avoiding problems such as deterioration of the quality, aesthetic appearance and workability, and lowering the oil price. In addition, the present inventors further added (d) a phosphorus-based extreme pressure agent and / or
Alternatively, the use of a sulfur-based extreme pressure agent together has led to the finding that rolling at even higher speeds becomes possible.

That is, the present invention relates to (a) one or more mineral oils and one or more selected from the group consisting of monoesters obtained from aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms. From 5% by weight to less than 40% by weight, (b)
An ester obtained from 5 to 70% by weight of fats and oils, and (c) one or more selected from the group consisting of dimer acids and polymer acids of higher aliphatic unsaturated acids having 16 to 20 carbon atoms, and polyols. A kinematic viscosity containing 20 to 90% by weight of a complex ester having a weight average molecular weight of 750 to 20000, wherein the remaining carboxyl group or hydroxyl group is esterified by a monohydric alcohol or monovalent fatty acid having 12 to 22 carbon atoms. Is 60mm ² /
a lubricating oil having a s (40 ° C) or more and a pour point of 10 ° C or less,
A rolling oil containing at least one water-soluble dispersant, wherein the water-soluble dispersant is a vinyl monomer containing at least one basic nitrogen atom or a cationic nitrogen atom, or a salt thereof or a fourth monomer. A homopolymer or copolymer of at least one monomer selected from the group consisting of a quaternary ammonium salt and a vinyl monomer or a salt thereof containing no basic nitrogen atom or cationic nitrogen atom. A polymer selected from the group consisting of a water-soluble cationic polymer compound and a water-soluble zwitterionic polymer compound having a weight average molecular weight in the range of 1,000 to 100,000, and rolling. Provided is a water-dispersed steel sheet cold rolling oil having an oil surface tension of 40 mN / m (25 ° C., Du Nouy tensiometer) or more.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION As described above, the lubricating oil used in the present invention is obtained from (a) mineral oil, an aliphatic carboxylic acid having 12 to 22 carbon atoms and an aliphatic alcohol having 1 to 12 carbon atoms. One or more selected from the group consisting of
(B) 5 to 70% by weight of fats and oils,
And (c) an ester obtained from at least one selected from the group consisting of dimer acids and polymer acids of higher aliphatic unsaturated acids having 16 to 20 carbon atoms, and polyols, and a residual carboxyl group or hydroxyl group. Are esterified with a monohydric alcohol or monovalent fatty acid having 12 to 22 carbon atoms, and complex esters 20 to 90 having a weight average molecular weight of 750 to 20,000.
% By weight.

The mineral oils of component (a) include, for example, paraffinic mineral oils such as spindle oil, turbine oil, cylinder oil and neutral oil, naphthenic mineral oils such as machine oil, and aroma mineral oils. . These mineral oils contribute to scum solubility and have an effect of improving the cleanliness around the mill. From the viewpoint of heat resistance and lubricity, a paraffinic mineral oil is more preferable. The viscosity of the mineral oil is more preferably 30 mm ² / s (40 ° C.) or less from the viewpoint of the effect of improving the cleanability around the mill.

The above monoester has 12 to 22 carbon atoms.
Which is obtained from a higher fatty acid and an aliphatic monohydric alcohol having 1 to 12 carbon atoms, for example, methyl stearate, butyl stearate, octyl stearate, lauryl stearate, methyl oleate, isodecyl oleate, butyl palmiate Tate, methyl behenate, methyl ester of tallow fatty acid, butyl ester of palm oil fatty acid, 2-ethylhexyl ester of coco oil fatty acid, lauryl ester of palm oil fatty acid and the like can be mentioned as typical examples. These monoesters contribute to scum solubility like mineral oils and have an effect of improving the cleanability around the mill, but from the viewpoint of scum solubility, monoesters are more preferable. When the carbon number of the aliphatic carboxylic acid used for the monoester is 22 and the carbon number of the aliphatic alcohol is larger than 12, the scum solubility tends to decrease,
When the number of carbon atoms of the aliphatic carboxylic acid is smaller than 12, lubricity decreases. The carbon number of the aliphatic carboxylic acid is preferably 12 to 20, and the carbon number of the aliphatic alcohol is preferably 4 to 10.

The mineral oils or monoesters of the component (a) may be used alone or in combination of two or more. The amount of the lubricating oil is 5 to 40% by weight of the lubricating oil, more preferably 10 to 30% by weight. It is a preferable addition amount from the viewpoint.

The fats and oils as the component (b) include animal and vegetable fats and oils such as beef tallow, tallow olein, lard, safflower oil, rapeseed oil, castor oil, palm oil, refined palm oil, palm olein, and coconut oil. Examples can be given. The fats and oils of the component (b) have an effect of lowering the oil price while substantially maintaining lubricity. Further, when the melting point of the fats and oils is lower than or equal to room temperature, it also has an effect of improving the cleanability around the mill. When the melting point is 10 ° C. or less, this effect is particularly significant. These oils and fats may be used alone or in combination of two or more. Further, the amount of the lubricating oil is 5 to 70% by weight, preferably 5 to 40% by weight of the lubricating oil. This is a preferable range from the viewpoint of reduction of oil price and lubricity.

The component (c) is an ester obtained from at least one selected from the group consisting of dimer acids and polymer acids of higher aliphatic unsaturated acids having 16 to 20 carbon atoms, and polyols. Carboxyl group or hydroxyl group has 12 carbon atoms
~ 22 are complex esters esterified with monohydric alcohols or monovalent fatty acids. The complex ester referred to in the present invention is a complex obtained by partially leaving a carboxyl group or a hydroxyl group in the above complex ester, and further linked by an ester bond with a polyol, a monohydric alcohol or a monohydric fatty acid, a dimer acid, or a polymer acid. It contains esters. If many hydroxyl groups remain in the composite ester, it is not preferable from the viewpoint of lubrication performance. The hydroxyl value of the composite ester is preferably 25 or less, more preferably 15 or less, and particularly preferably 10 or less. The acid value of the composite ester is
If it is too high, the thermal stability and the emulsion stability will be reduced, so that it is usually preferred to be 10 or less.

The dimer acid and polymer acid used herein are dimer acid and polymer acid of higher aliphatic monoenoic acid or dienoic acid having 16 to 20 carbon atoms, for example, somaric acid, oleic acid, linoleic acid, gadolinic acid, tall acid, and tall acid. The dimer and polymer acids of oil fatty acids are mentioned. Preferred are dimer acids and polymer acids of higher fatty acid monoenoic acid or dienoic acid having 18 carbon atoms.

Examples of polyols include propylene glycol, ethylene glycol, dipropylene glycol, diethylene glycol, neopentyl glycol, butanediol, pentanediol, polyoxyethylene glycol, polyoxypropylene glycol,
Examples include trimethylolpropane, pentaerythritol, glycerin, and polyols further added with alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide. Preferred are propylene glycol, ethylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol and the like.

The monohydric alcohol having 12 to 22 carbon atoms includes
For example, lauryl alcohol, myristyl alcohol, palmityl alcohol, stearyl alcohol, behenyl alcohol, oleyl alcohol and the like can be mentioned. Examples of the monovalent fatty acid having 12 to 22 carbon atoms include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, oleic acid, erucic acid, tallow fatty acid, palm oil fatty acid, and coconut oil fatty acid. . Preferred are monohydric alcohols having 16 to 20 carbon atoms and monovalent fatty acids having 16 to 20 carbon atoms, and particularly preferred are palmityl alcohol, stearyl alcohol, oleyl alcohol, palmitic acid, stearic acid, oleic acid, tallow fatty acid, Palm oil fatty acids, coconut oil fatty acids and the like.

The complex ester of component (c) has a greater number of ester groups and a higher kinematic viscosity than fats and oils such as beef tallow, which has been conventionally used as a lubricating component, and therefore has a remarkable lubricating effect. The molecular weight of the complex esters is from 750 to 20,000, more preferably from 750 to 7,500. If the molecular weight is less than 750, lubricity tends to be inferior to oils and fats, and
If it is more than 20000, the solubility in lubricating components will decrease,
In addition, since the viscosity tends to be high, a problem may occur in handling. The molecular weight mentioned here is a weight average molecular weight and is measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

The complex ester of the component (c) may be one kind, or two or more kinds may be used in combination. Further, the amount of addition is used in the range of 20 to 90% by weight of the lubricating component. If the amount is less than 20% by weight, the effect of improving lubricity cannot be expected much. From the viewpoint of the balance between lubricity and oil price, 30 to 60% by weight is more preferable. However, even if it exceeds 60% by weight, 2500m in the future
/ Min for high-speed rolling.

The lubricating oil used in the present invention has a kinematic viscosity of 60 mm ² /
s (40 ° C) or more, and the pour point is 10 ° C or less. When the kinematic viscosity is less than 60 mm ² / s (40 ° C.), the difference in lubricity from the conventional tallow-based rolling oil becomes small. Preferably 65mm ² / s (40 ℃) or higher, more preferably 70mm ² / s (40
° C) or higher. Also, if the pour point is higher than 10 ° C,
In winter, the fluidity deteriorates and the scum accumulation resistance tends to decrease.

As described above, the composition contains the components (a) to (c),
When a cold rolling oil for water-dispersed steel sheet showing a predetermined kinematic viscosity and pour point is used, high-speed rolling can be performed without occurrence of slip or chattering, and scum around the mill can be formed. This reduces sedimentation and avoids the dangers of fire, poor aesthetics and poor workability, while avoiding an increase in oil prices. The achieved rolling speed is 1700-2800 m / min for soft materials, preferably 1750-28
00 m / min, more preferably 1800 to 2800 m / min. For hard materials this is between 1500 and 2500 m / min, preferably 15
50 to 2500 m / min.

In the present invention, one or more components selected from the group consisting of a phosphorus-based extreme pressure agent and a sulfur-based extreme pressure agent as the component (d) can be further contained in the above lubricating component. Examples of the phosphorus-based extreme pressure agent include trioctyl phosphate, tricresyl phosphate, trioleyl phosphate, dioctyl acid phosphate, dilauryl acid phosphate, tributyl phosphite, trioleyl phosphite, ditridecyl acid phosphite, and dioleyl acid phosphite. Phyto and aromatic amine salts of mono-2-ethylhexyl acid phosphate. Examples of the sulfur-based extreme pressure agent include sulfurized lard, sulfurized fats and oils such as sulfurized tallow and sulfurized vegetable oil esters, sulfurized olefins, activated and inactivated sulfurized mineral oils, dibenzyl disulfide, di-tert-butyl disulfide, and zinc, respectively. -Dialkyldithiophosphate and the like.

The addition of the phosphorus-based extreme pressure agent and the sulfur-based extreme pressure agent as the component (d) contributes to seizure resistance and has the effect of further improving the rolling speed. These phosphorus-based extreme pressure agents and sulfur-based extreme pressure agents may be used alone or in combination of two or more. Also, the amount of addition is 0.5 to
Used in the range of 5% by weight. The lubricating property is improved as the amount of addition increases, but if it exceeds 5% by weight, the oil price tends to increase, but the improvement in seizure resistance against the increase decreases. From the balance between the oil price and the effect of improving lubricity, the range of 1.0 to 3% by weight is more practical and preferable.

When the component (d) is contained, the accumulation of scum around the mill is reduced without causing slipping or chattering, and the danger of fire, deterioration of appearance and deterioration of workability are avoided. It is possible to perform high-speed rolling.

Lubricating oil used in the present invention (lubricating oil for rolling)
Is used as a water-dispersed rolling oil by dispersing a lubricating component in water using a water-soluble dispersant. In addition, lubricating oil for rolling oil refers to oil (lubricant) only,
Generally, it is marketed in this form. Rolling oil refers to a dispersion of such lubricating oil for rolling oil in water. Generally, cold rolling is supplied to the processing section in the form of this rolling oil. It is sometimes called a rolling oil emulsion or a coolant. Further, the lubricating oil referred to herein refers to a lubricating oil for rolling oil containing a water-soluble dispersant that forms a form in which lubricating oil is dispersed in water when mixed with water.

The water-soluble dispersant may be contained in the lubricating oil or may be supplied separately from the lubricating oil and mixed with the lubricating oil and water to form an emulsion. Usually, (a) ~
To the lubricating component composed of the component (c), if necessary, the component (d), an oiliness improver, an extreme pressure additive, an antioxidant, etc. described below are added to form a lubricating oil, and then a dispersant is added to water Disperse. The mixing ratio at this time is not particularly limited,
Usually, it is preferable that the concentration of the lubricating oil in the water-dispersed rolling oil is 1 to 20%. If it is less than 1%, a sufficient effect as a rolling oil cannot be expected, and if it exceeds 20%, it becomes difficult to obtain an effect corresponding to the increase.

As the water-soluble dispersant, known dispersants can be used.
Used in the range of weight percent. It is preferably from 0.5 to 5% by weight, particularly preferably from 0.5 to 3% by weight. Such water-soluble dispersants include, for example, the following-, namely, a homopolymer of a vinyl monomer containing at least one basic nitrogen atom or a cationic nitrogen atom or a salt thereof or a quaternary ammonium salt, or A vinyl monomer containing at least one basic nitrogen atom or cationic nitrogen atom or a salt or quaternary ammonium salt thereof, and containing no basic nitrogen atom or cationic nitrogen atom Copolymers of vinyl monomers or salts thereof, salts of ethyleneimine ring-opening polymers or quaternary ammonium salts, polycondensates of aliphatic dicarboxylic acids with polyethylene polyamines or dipolyoxyethylene alkylamines Salt or quaternary ammonium salt, dihaloalkane-polyalkylenepolyamine polymer, epihalohydrin-amine polycondensate A polymer selected from the group consisting of salts or starch or cellulose or their cationic modified product of chitosan, its average molecular weight of 10
It is possible to use one having as a main component one or more dispersant components selected from the group consisting of a water-soluble cationic polymer compound and a water-soluble zwitterionic polymer compound in the range of 100 to 10000000. it can. Such a water-soluble cationic polymer compound and a water-soluble zwitterionic polymer compound must contain a basic nitrogen atom or a cationic nitrogen atom. It may contain groups such as amides and esters, examples of which include:

(1) Vinyl monomers containing at least one basic nitrogen atom or cationic nitrogen atom represented by the following general formulas (I) to (V) (hereinafter referred to as "nitrogen-containing vinyl Or quaternary ammonium salts, or copolymers of two or more of these.

[0028]

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Wherein A is —O— or —NH—, n ₁
Represents an integer of 1 to 3, R ₁ represents H or CH ₃ , and R ₂ and R ₃ represent H, CH ₃ or C ₂ H ₅ ]

[0030]

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[0031]

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[0032]

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[0033]

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Specific examples of these monomers include dimethylaminoethyl acrylate, diethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl acrylamide, diethylaminopropyl acrylamide, dimethylaminopropyl methacrylamide of the formula (I) , Diethylaminopropyl methacrylamide and the like;
Dimethylaminomethylethylene, diethylaminomethylethylene, dimethylaminomethylpropene of the formula (II),
Diethylaminomethylpropene, etc .: vinylpyridine of formula (III), etc .: vinylpiperidine of formula (IV), vinyl-N
-Methylpiperidine and the like; vinylbenzylamine of the formula (V), vinyl-N, N-dimethylbenzylamine and the like.

Among the homopolymers or copolymers of these monomers, those having an average molecular weight of 1,000 to 100,000 are used.

(2) One or more of the nitrogen-containing vinyl monomers represented by the above general formulas (I) to (V) or salts or quaternary ammonium salts thereof, and α, β-non Saturated carboxylic acid or its salt or its derivative, sulfonic acid group-containing vinyl compound or its salt, acrylonitrile, vinylpyrrolidone and a basic nitrogen atom and a cationic nitrogen atom selected from the group consisting of aliphatic olefins having 2 to 20 carbon atoms A copolymer with one or two or more vinyl-based monomers not containing (hereinafter, abbreviated as "vinyl-based monomer").

Examples of the vinyl monomer include vinyl pyrrolidone, acrylonitrile; acrylic acid, methacrylic acid, maleic acid or alkali metal salts, ammonium salts, amide compounds or esterified products of these acids; vinyl sulfonic acid, Examples thereof include rilsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, p-styrenesulfonic acid, and alkali metal salts or ammonium salts of these acids. Then, among the copolymers of the nitrogen-containing vinyl monomer and the vinyl monomer, those having an average molecular weight of 1,000 to 100,000,000 are used.

(3) A salt of a ring-opening polymer of ethyleneimine or a quaternary ammonium salt.

Specifically, there can be mentioned those having a repeating unit represented by the following general formula (VI) and having an average molecular weight of 1,000 to 100,000,000.

[0040]

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Wherein n ₂ is an integer of 1 to 5, and n ₃ is 0 to 5
(4) A salt or a quaternary ammonium salt of a polycondensate of an aliphatic dicarboxylic acid and a polyethylene polyamine or a dipolyoxyethylene alkylamine. Specifically, the repeating unit is a polycondensate with a polyethylene polyamine represented by the general formula (VII) and a polycondensate with a dipolyoxyethylene alkylamine represented by the general formula (VIII) and has a molecular weight of 1000 to 100,000,000.

[0042]

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Wherein R ₄ is a dimer acid residue or an alkylene group having 1 to 10 carbon atoms, R ′ is —CH ₂ CH ₂ —, and n ₄ is an integer of 2 to 7.

[0044]

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Wherein R ₄ is the same as in formula (VII). R ₅ represents an alkyl group having 1 to 8 carbon atoms, R ₆ represents H or CH ₃ , and n ₅ and n _{6 each} represent an integer of 1 to 10.] Examples of the aliphatic dicarboxylic acid include dimer acid and adipic acid. As a polyethylene polyamine,
Diethylenetriamine, triethylenetetramine and the like can be used.

(5) Dihaloalkane-polyalkylene polyamine polycondensate.

Specifically, 1,2-dichloroethane,
A polycondensate which is a quaternary ammonium salt of a dihaloalkane such as 1,2-dibromoethane or 1,3-dichloropropane and a polyalkylene polyamine having two or more tertiary amino groups in a molecule; And those having an average molecular weight of 1,000 to 100,000,000.

The above polyalkylene polyamine includes
These include:

[0049]

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(6) Epihalohydrin-amine polycondensate.

Specifically, the repeating unit has the following general formula (IX)
And an average molecular weight of 1,000 to 100,000,000.

[0052]

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Wherein R _{7 to} R ₉ are CH ₃ or C ₂ H ₅ , X ⁻
Represents a halogen ion.] (7) Chitosan salt or cationically modified starch or cellulose.

The above polymers (1) to (6) more preferably have an average molecular weight of 10,000 to 100,000.

Further, as an anion as a counter ion for forming a salt of a nitrogen-containing vinyl monomer or a quaternary ammonium salt which gives a water-soluble cationic polymer compound or a water-soluble zwitterionic polymer compound, sulfuric acid is used. Ion, nitrate ion, chloride ion, glycolate ion, acetate ion,
Phosphate ions and the like, among which organic or inorganic phosphate ions having an acidic phosphate group, or borate ions are preferred from the viewpoint of lubricity or rust prevention, but also hinder the application of other counter ions. Not something.

These water-soluble cationic or zwitterionic polymer compounds can be used alone or in admixture of two or more, and as described above, 0.1 to 10% based on the total amount of the rolling oil composition. % By weight.

The mechanism of action of the water-soluble cationic polymer compound and the water-soluble zwitterionic polymer compound of the above (1) to (7) has not been completely elucidated, but is considered to be roughly as follows. . That is, the water-soluble cationic or zwitterionic polymer compound completely dissolved in the aqueous layer adsorbs the lubricating oil component particles that have been micronized in response to mechanical shearing force before coalescence begins, The polymer compound turns the oil particles into large particles by a kind of coagulation,
Furthermore, the large particles are stably dispersed in water by the three-dimensional and electrically protective colloidal action of the polymer compound.

More preferred water-soluble dispersants include:
Vinyl monomers containing one or more basic nitrogen atoms or cationic nitrogen atoms or their salts or quaternary ammonium salts, and vinyl monomers containing no basic nitrogen atoms or cationic nitrogen atoms Or a polymer selected from the group consisting of homopolymers or copolymers of one or more monomers selected from the group consisting of salts thereof, and having a weight average molecular weight of 1000
It is at least one selected from the group consisting of a water-soluble cationic polymer compound and a water-soluble zwitterionic polymer compound in the range of from 1 to 1,000,000. More specifically, the compound of the above (1) or (2) is exemplified.

The use of the cold-rolling oil for water-dispersed steel sheets of the present invention makes it possible to roll steel sheets at a speed of 1700 m / min or more for soft materials and 1500 m / min for hard materials. The high-speed rolling according to the present invention can be achieved by a cold rolling oil for water-dispersed steel sheets. That is, in the emulsified rolling oil in which only the lubricating oil is emulsified with a nonionic surfactant or the like, the oil unevenly adheres to the steel sheet, causing slip and chattering,
Sufficient high-speed rolling cannot be performed. By using the above-mentioned dispersant to form a water-dispersion type, the base oil can be uniformly wet and spread over the processed part for the first time, so that high-speed rolling can be performed without occurrence of slip, chatter, etc. It is.

The rolling oil of the present invention has a surface tension of 40 mN /
m (25 ° C., Du Nouy tensiometer) or more. A lubricating oil emulsion containing a surfactant as a main emulsifier has a low surface tension, exhibits lipophilicity, and therefore has poor wettability to rolling rolls and poor cooling performance. On the other hand, an emulsion of a lubricating oil containing a water-soluble dispersant as a main emulsifier as described above has a high surface tension and exhibits hydrophilicity. Such an emulsion is excellent in emulsification stability, has good wettability to rolling rolls, and also has excellent cooling properties, and is suitable for high-speed rolling. In particular, when the surface tension is 40 mN / m or more, the above characteristics are excellent. 45 to 70 mN / m is more preferred.

The cold-rolling oil for a water-dispersed steel sheet of the present invention includes:
In addition to the above components, if necessary, various known additives such as other lubricants, oiliness improvers, rust inhibitors, antioxidants, and emulsifiers can be added.

As other lubricants, hindered esters composed of polyhydric alcohols and fatty acids are used. As oiliness improvers, for example, fatty acids such as oleic acid, tallow fatty acid, palm oil fatty acid, and polymer acid of tall oil fatty acid are used. These can be added up to about 10% by weight in the lubricating oil for cold-rolling oil of the water-dispersed steel sheet of the present invention.

As the rust inhibitor, for example, alkenyl succinic acid and its derivatives, fatty acids such as oleic acid, esters such as sorbitan monooleate, and other amines can be used. These are used in the lubricating oil used in the present invention. It can be added up to about 2% by weight.

As the antioxidant, for example, 2,4
Phenolic compounds such as -di-tert-butyl p-cresol and tetrakis [methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane; and aromatics such as phenyl α-naphthylamine and phenothiazine. Group amines and the like can be used, and these can be added to the lubricating oil used in the present invention up to about 5% by weight.

Examples of the emulsifier include anionic surfactants such as triethanolamine oleate and sodium petroleum sulfonate, and nonionic surfactants such as polyoxyethylene nonylphenyl ether and polyoxyethylene sorbitan triolate. An agent or the like can be used in a range that does not affect the lubricating performance.

In the high-speed rolling method using the rolling oil of the present invention, when the steel sheet is rolled to a thickness of 1.5 mm or less in a cold rolling mill, the above-mentioned components (a) to (c) are contained. By using a lubricating oil having a kinematic viscosity of 60 mm ² / s (40 ° C.) or more and a pour point of 10 ° C. or less, and preferably a high-pressure viscosity of 140 mPa · s or more determined by the following formula (1): High speed rolling is possible at a speed of 1700 m / min or more for soft materials and 1500 m / min for hard materials.

The high-speed rolling method using the rolling oil of the present invention is suitable for rolling a steel sheet to a thickness of 1.5 mm or less, more preferably 0.5 mm or less. In cold rolling of steel sheets, the productivity has been a problem due to the reduction in thickness.However, especially when the thickness is 0.5 mm or less, the temperature rise of the sheet due to processing heat is large, and heat scratches occur frequently. Therefore, the rolling speed cannot be increased with the conventional tallow-based cold rolling oil, and the productivity is reduced. In order to ensure the same productivity, it is necessary to increase the rolling speed by an amount corresponding to the reduction in the sheet thickness, but the rolling speed has to be reduced with the conventional oil. Due to the future increase in steel sheet tension and advances in thin-wall thickness processing technology, it is expected that the thickness will become increasingly thinner.However, in order to maintain and increase productivity, increase the rolling speed at thicknesses of 0.5 mm or less. It is very important that

In this high-speed rolling method, the high-pressure viscosity is preferably 140 mPa · s or more. The high-pressure viscosity here is obtained by the following equation (1). η = η ₀ · exp (α · P) (1) (where, in the formula (1), η represents the high-pressure viscosity (unit: mPa · s) of the lubricating oil at 130 ° C. and 300 MPa, and η ₀ is 130 ℃,
Represents the normal pressure viscosity (unit: mPa · s) of the lubricating oil at 0.1 MPa, P represents the pressure applied to the lubricating oil at 300 MPa, and α represents the pressure viscosity coefficient of the lubricating oil (unit: kPa ⁻¹ × 10 ⁵ ) ). Further, α is obtained by Expression (2). α = (0.1657 + 0.2332 · Logη ₀ ) · m ₀ (2) (where, in the formula (2), m ₀ is a temperature viscosity coefficient (unit:
K ^-1 ) and is obtained from the viscosity measurement results of the lubricating oil at two temperatures at normal pressure using the following ASTM-Walther equation. _{Log (Log (η m +0.7)} ) = - m q · LogT + n ... ASTM Walter formula (However, eta _m each viscosity of the lubricating oil at a temperature 2 levels (mm ²
/ s), T represents temperature (K), and n is a constant)).

As the cooling and lubricant in the cold rolling of the steel sheet, an emulsion in which the lubricating oil used in the present invention is dispersed in water is used. The emulsion is broken from the O / W emulsion at the inlet high-pressure section of the rolling section, introduced into the processing section by oil alone, and water is eliminated and hardly introduced into the processing section. The main factors that determine the rolling lubricity are the amount of oil introduced into the processing area and the boundary friction coefficient. Among them, the boundary friction coefficient (the degree to which a strong adsorption film is formed on the metal surface) is determined by the lubricating oil composition. Is under high temperature and high pressure at the entrance of rolling process (usually 100 ~ 150 ℃, 100 ~ 700MPa)
Determined by the viscosity of the lubricating oil. When the viscosity is appropriate and the amount of oil introduced into the processing section increases, the contact ratio between the steel sheet and the rolling roll decreases, and the occurrence of heat scratch can be suppressed. In the high-speed rolling method using the rolling oil of the present invention, the lubricating oil has a high-pressure viscosity of 140 mP at 300 ° C. and 300 MPa.
a · s or more, but the amount of oil introduced into the processing section obtained in this case is larger than that of the conventional tallow-based cold rolling oil,
High-speed rolling of 1,700 m / min or more and 1500 m / min or more with hard materials is possible. When the high-pressure viscosity of the lubricating oil is 170 to 300 mPa · s, high-speed rolling becomes possible, which is more preferable. For further high-speed rolling in the future, it is particularly preferable that the high-pressure viscosity of the lubricating oil is 200 to 300 mPa · s.

As an example of the procedure for calculating the high-pressure viscosity η, first, the kinematic viscosities of the lubricating oil at 40 ° C. and 100 ° C. are measured. Measurement result A
When input to the STM-Walther equation, a simultaneous equation of two variables is established, and m ₀ and n are derived. Next, the kinematic viscosity η at 130 ° C
_{When 0} is calculated by the ASTM-Walther equation, and the equation (2) is input together with m ₀ , the pressure viscosity coefficient α is calculated. Finally (1)
The viscosity η at 130 ° C. and 300 MPa according to the formula, η ₀ previously calculated,
It is calculated by inputting α and 300 MPa.

[0071]

The water-dispersed rolling oil obtained by using the lubricating oil for rolling oil according to the present invention is characterized in that the dispersed particles of the lubricating oil have an appropriate particle size,
Since the uniform emulsification and dispersibility and the particle size distribution can be kept stable for a long period of time, even when used by circulating through a cold rolling mill, good initial rolling lubricity can be maintained for a long period of time. In addition, when the processed part is at a high temperature, such as during high-speed rolling, the conventional emulsified rolling oil using a high-viscosity base oil causes the oil to adhere unevenly and cause slip and chattering. By doing so, the base oil uniformly wets and spreads over the processed portion, so that there is no occurrence of slip or the like due to the high-viscosity base oil. In addition, the use of a base oil having a high viscosity and a high seizure resistance suppresses an increase in temperature due to frictional heat between the roll and the steel plate interface, so that seizure does not occur even during high-speed rolling. Furthermore, since the pour point is 10 ° C. or less, there is almost no decrease in the scum deposition resistance even in winter. In addition, the base oil has a high viscosity and the amount of oil spread can be reduced by using a high seizure-resistant base oil. There is also.

Further, in the high-speed rolling method using the rolling oil of the present invention, the lubricating oil has good rolling lubricity as described above, and at the same time, satisfies a predetermined high-pressure viscosity to maintain a good amount of oil introduced into the working part. 17 can be made of soft material
The steel sheet can be rolled to a thickness of 1.5 mm or less at a speed higher than the conventional speed of at least 00 m / min and at least 1500 m / min for hard materials.

[0073]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

[0074] After mixing the Examples 1 6 and Comparative Examples 1 to 8 Table 1 and various rolling oil compositions shown in Table 2 (the present invention Example 1 to 6 and Comparative Examples 1 to 8), pressurized at 60 to 90 ° C. While warming, the mixture was uniformly dissolved by stirring with a DC stirrer. Next, after mixing oil and tap water so as to have the oil concentration described in each test condition described below, the mixture was heated and stirred with a homomixer to prepare an emulsion. About the obtained emulsion, by the test examples shown below, lubricity,
The degreasing property, scum accumulation resistance, grain size stability, and high-speed rolling property were evaluated. The results are shown in Tables 1 and 2.

Test Example 1 (Rolling test) For each of the prepared rolling oils, a two-high rolling mill (200 mmφ × 2
(100mm width, SUJ-2, Hs = 90), a strip single pass rolling test was conducted under the following conditions, and the rolling load (tonf / m) when the rolling reduction was 40%
Was evaluated for lubricity. If the rolling load is lower than 95% of the conventional commercial lubricating oil for tallow cold rolling oil, the lubricity is good. Moreover, the degreasing property was evaluated based on the water wetted area ratio (%) of the rolled steel sheet degreased under the following conditions. The degreasing property is good if the water wetted area ratio is 80% or more.

(Rolling conditions) Rolled material: Mild steel (SPCC-B, 30 mm width x 700 mm length x 2 mm)
Thickness, Ra = 0.02μm) Roll roughness: Polished in the rolling direction with abrasive paper, Ra = 0.3
Adjust to 0.40.4 μm (Rz = 2.8 to 3.2 μm).

Sheet temperature: 100 ° C. Rolling speed: 400 m / min Reduction rate: 40% Number of rolls: 2 Rolling oil concentration: 3 vol.% Rolling oil temperature: 60 ° C. Stirring conditions: M type homomixer 9000 rpm Spray amount: 2 liters / minute, 1 kgf / cm ² (degreasing conditions) Degreasing solution: 2% sodium hydroxide solution + 0.1% polyoxyethylene nonylphenyl ether (HLB = 12.4) + 0.1% sodium gluconate solution Degreasing method: immersion → electrolysis → brush → Rinse Immersion condition: 80 ° C, 1 second Electrolytic condition: 80 ° C, 5A / dm ² , 1 second Brush condition: 500rpm reverse direction, 1 time Rinse condition: 50 ° C hot water spray (1 liter / min × 3)
Seconds) Test Example 2 (Continuous rolling test) Using the above-mentioned two-high rolling mill,
A coil tension three-pass rolling test was performed under the following conditions, and the scum accumulation resistance was evaluated based on the amount of accumulated scum (g). If the amount of deposited scum is less than 50% of the conventional commercially available lubricating oil for tallow cold rolling oil, the scum deposited resistance is good. The particle size of the emulsion before and after the test was measured with a Coulter counter, and the absolute value (μ) of the change in the average particle size (volume distribution) was measured.
The particle size stability was evaluated from m). If the absolute value of the variation is 2 μm or less, the particle size stability is good.

(Rolling conditions) Rolled material: Mild steel (SPCC-D, 50 mm width x 100 mm length x 1 mm)
Thickness, Ra = 0.5μm) Roll roughness: Adjust to Ra = 1.5μm Plate temperature: normal temperature Rolling speed: 10m / min Rolling tension: 7kgf / mm ² Reduction ratio: 25% for each pass (total reduction ratio 58%) Rolling oil concentration: 3 vol.% Liquid condition: 60 ° C, 10 liter Stirring condition: M type homomixer 9000 rpm Spray rate: 1 liter / min, 1 kgf / cm ² , 1 nozzle each at the top and bottom of the nozzle Atmospheric temperature: 20 ° C Test example 3 (High-speed rolling test) The prepared rolling oil was subjected to high-speed rolling of a thin plate under the following conditions, and the high-speed rolling property was evaluated by a maximum rolling speed (m / min) at which heat scratch and slip did not occur. The evaluation used was high-speed rollability 1 and the evaluation using a hard material was high-speed rollability 2). The maximum rolling speed for high-speed rolling 1 is 1700 m / min or more, or the maximum rolling speed for high-speed rolling 2 is
If it is 1500 m / min or more, the high-speed rolling property is good.

(Rolling conditions) Rolling mill: One-way type two-high rolling mill (530 mmφ × 120 mm width,
Special forged steel, Hs = 90) Rolled material: Soft material (SPCC-B, C = 0.08% by weight, 30mm width × 700mm length × 2.0mm thickness, Ra = 0.02μm) Hard material (C = 0.12)
Weight%, 30mm width x 700mm length x 2.0mm thickness, Ra = 0.3μm) Roll roughness: Ra = 0.3μm Plate temperature: 100 ° C Rolling speed: 500-2000m / min Reduction ratio: 35% Rolling oil concentration: 4 vol.% Liquid Conditions: 60 ° C., 20 liters Stirring conditions: M-type homomixer 9000 rpm Spray rate: 1 liter / min, 1 kgf / cm ²

[0080]

[Table 1]

[0081]

[Table 2]

In Tables 1 and 2, the mineral oils, monoesters, fats and oils, composite esters, dispersants and other additives of the rolling oil component mean the following.

Mineral oil A: paraffinic mineral oil (10 mm ² / s (40 ° C.)) Mineral oil B: paraffinic mineral oil (28 mm ² / s (40 mm)
C)) Monoester A: 2-ethylhexyl stearate Monoester B: isodecyl stearate.

Oil A: refined palm oil (iodine value 65, melting point 8 ° C.) Oil B: safflower oil (iodine value 70, melting point 0)
℃) Oil and fat C… Tallow olein (iodine value 60, melting point 20)
° C).

Complex ester A: Polymer acid of oleic acid (dimer acid: polymer acid of trimer acid or higher = 60: 40)
(Weight ratio)) / diethylene glycol / oleyl alcohol = 2/1/2 (molar ratio) (acid value: 8, hydroxyl value: 6, weight average molecular weight: 1800) Complex ester B: Polymer acid of tall oil fatty acid (dimer) Acid: polymer acid equal to or greater than trimer acid = 75: 25 (weight ratio)) / pentaerythritol / oleic acid = 1/2/6
Ester obtained from (molar ratio) (acid value 4, hydroxyl value 8, weight average molecular weight 3000) Complex ester C: Polymer acid of tall oil fatty acid (dimer acid: polymer acid of trimer acid or higher = 90: 10 (weight ratio)) ) / Trimethylolpropane / palm oil fatty acid = 1 /
Esters obtained from 2/4 (molar ratio) (acid value 3, hydroxyl value 6, weight average molecular weight 1900).

Extreme pressure agent A: Trioleyl phosphate Extreme pressure agent B: Aromatic amine salt of mono-2-ethylhexyl acid phosphate Extreme pressure agent C: Sulfurized lard (active type, S% = 10.5)
%).

Other A: Oiliness improver (palm oil fatty acid) Other B: Rust inhibitor (hexadecenyl succinic acid) Other C: Antioxidant (phenyl-α-naphthylamine) Other D: Emulsifier (polyoxyethylene nonyl) Phenyl ether, HLB = 12.4) Other E: ester obtained from trimethylolpropane / oleic acid / stearic acid = 14.4 / 60.0 / 25.6 (weight ratio) (acid value: 5) Other F: pentaerythritol / oleic acid / stearic acid = Ester obtained from 14.4 / 60.0 / 25.6 (weight ratio) (acid value 5) Other G pentaerythritol / (isostearic acid: oleic acid: linoleic acid = 70: 28: 2 (weight ratio)) = 1/3 (mol) Ester obtained from (ratio) Other H ... sebacic acid / pentaerythritol / (isostearic acid: oleic acid: lino) Le acid = 70:
Esters obtained from 28: 2 (weight ratio)) = 1/2/4 (molar ratio) Others I ... 2 ethylhexyl alcohol / (stearic acid: oleic acid = 1: 1 (weight ratio)) = 1/1
Ester obtained from (molar ratio) Others J: Polymeric acid of tall oil fatty acid (dimeric acid: polymeric acid of trimeric acid or more = 7: 3 (weight ratio)).

Dispersant A: neutralized glycolic acid of dimethylaminoethyl acrylate / dodecyl methacrylate / sodium methacrylate = 3/1/1 (molar ratio)
(Weight average molecular weight = 100,000) Dispersant B ... glycolic acid neutralized homopolymer of dimethylaminopropyl acrylamide (weight average molecular weight = 300,000) Dispersant C ... in phosphoric acid of dimethylaminoethyl methacrylate Copolymer of hydrate / sodium acrylate = 6/1 (molar ratio) (weight average molecular weight = 600,000) Dispersant D: caprylic acid neutralized product of homopolymer of diethylaminoethyl methacrylate (weight average molecular weight =
30,000) Lubricating oil for commercial tallow rolling oil ... tallow / emulsifier = 98% by weight /
2% by weight Further, the method for measuring the weight average molecular weight of the complex ester and the dispersant is as follows.

1) Complex esters (the results of GPC molecular weight analysis are displayed as they are) (Conditions) Column: HS6K (silica gel) x 2 Column temperature: (40 ° C) Eluent: THF (tetrahydrofuran) Detection Instrument: RI (refractometer)-Injection amount: 3 wt% THF solution, 20 microliter-Liquid flow rate: 1.0 ml / min-Molecular weight standard: polystyrene 2) Dispersants (GPC molecular weight analysis after hydrolysis, (Condition)-Column: G2000SW (silica gel) x 2-Column temperature: (40 ° C)-Eluent: 0.1N sodium chloride solution / acetonitrile = 70/30 (weight)・ Detector: RI (refractometer) ・ Injection volume: 1% by weight eluent, 20 microliter ・ Liquid flow rate: 0.4 ml / min ・ Molecular weight standard: polystyrene sulfone Sodium.

As is clear from the results shown in Tables 1 and 2, the rolling oil of the present invention is superior in all performances as compared with the comparative product. In comparison with the commercially available tallow-based cold rolling oil of Comparative Product 1, it is excellent in lubricity, scum accumulation resistance, particle size stability, and high-speed rolling property. In addition, by containing a predetermined complex ester and having a predetermined high-pressure viscosity, a soft material
Rolling at a high speed of 1700 m / min or more and a hard material of 1500 m / min or more is possible. Particularly in the case of the illustrated embodiment, extremely good high-speed rolling of 1800 m / min or more for a soft material and 1550 m / min or more for a hard material is possible.

[0091]

The cold-rolled oil of the water-dispersed steel sheet according to the present invention comprises:
(C) Since the composite esters have better lubricity than conventional lubricating oils for beef tallow rolling oil, and because there is no slip due to an increase in particle size during long-term use, productivity is improved by high-speed rolling. Can be achieved. In particular, when this composite ester is contained and has a predetermined high-pressure viscosity, when the steel sheet is rolled to a thickness of 1.5 mm or less in a cold rolling mill, the soft material is 1,700 m / min or more, and the hard material is 1,500 m / min.
High speed rolling can be performed at a speed of more than one minute. (A)
The scum accumulation around the mill is reduced by the components, and it is possible to improve the danger of fire, deterioration of aesthetic appearance, and deterioration of workability. Further, by containing the component (b), the cost is lower than that of the conventional synthetic ester-based lubricating oil for cold rolling oil without deteriorating the cleaning property, and the operation with the conventional synthetic ester-based lubricating oil for cold rolling oil is performed. It is possible to avoid an increase in cost. In addition, the reduction in the concentration of lubricating oil for rolling oil and the improvement in oil consumption per unit due to the occurrence of scum, etc., make it possible to produce steel plates at lower cost and higher efficiency compared to the conventional operation using tallow-based rolling oil. Has excellent effects.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI C10M 107: 30) C10N 20:00 20:02 20:04 30:04 40:24 (72) Inventor Takehiko Ichimoto 1334 Minato, Wakayama-shi, Wakayama Kao Corporation Research Laboratory (72) Inventor Kenichi Miyamoto 1334 Minato 1334 Minato, Wakayama City, Wakayama Prefecture Kao Corporation Research Laboratory (56) References JP-A-5-98283 (JP, A) JP-A-5-43888 (JP, A) JP-A-3-192197 (JP, A) JP-A-1-139694 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C10M 173/00 C10M 101/02-101/04 C10M 105/34 C10M 105/42

Claims (3)

(57) [Claims] (1) 5% by weight of (a) mineral oil and one or more selected from the group consisting of monoesters obtained from aliphatic carboxylic acids having 12 to 22 carbon atoms and aliphatic alcohols having 1 to 12 carbon atoms. % To less than 40% by weight, (b) 5 to 70% by weight of fats and oils, and (c) one or more selected from the group consisting of dimer acids and polymer acids of higher aliphatic unsaturated acids having 16 to 20 carbon atoms. And an ester obtained from a polyol, and the remaining carboxyl group or hydroxyl group is an ester having 12 to 22 carbon atoms.
Complex esters having a weight average molecular weight of 750 to 20,000, which are esterified with a polyhydric alcohol or a monohydric fatty acid, 20 to
A lubricating oil containing 90% by weight and having a kinematic viscosity of 60 mm ² / s (40 ° C.) or more and a pour point of 10 ° C. or less, and a water-soluble dispersant
A water-soluble dispersant, wherein the water-soluble dispersant is a vinyl monomer containing at least one basic nitrogen atom or a cationic nitrogen atom or a salt or quaternary ammonium salt thereof; Selected from the group consisting of homopolymers or copolymers of one or more monomers selected from the group consisting of vinyl monomers containing no cationic nitrogen atoms or cationic nitrogen atoms or salts thereof And its weight average molecular weight is 1000
At least one member selected from the group consisting of a water-soluble cationic polymer compound and a water-soluble zwitterionic polymer compound having a surface tension of 40 mN / m.
(25 ° C, Du Nouy's tensiometer) or higher, water-dispersed steel sheet cold rolling oil. 2. The lubricating oil (b) has a melting point of 10
The cold-rolled oil for water-dispersed steel sheets according to claim 1, wherein the temperature is not higher than 0 ° C. 3. The lubricating oil further comprises at least one member selected from the group consisting of (d) a phosphorus-based extreme pressure agent and a sulfur-based extreme pressure agent.
The water-dispersed cold-rolled steel sheet oil according to claim 1, wherein the cold-rolling oil comprises water by weight.