JP2001240884A - Cold rolling oil for stainless steel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold rolling oil for stainless steel, hardly causing seizing, a heat scratch or the like under a high draft, and further, hardly causing uneven brightness even if the rolling speed is increased under a low draft. SOLUTION: This cold rolling oil for stainless steel contains a diester represented by the formula (1): R1-O-CO(CH2)nCO-O-R2 (1) (wherein, R1 and R2 are mutually the same or different group of a 3-5C hydrocarbon group; and n is a number of 4-8).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a cold rolling oil for stainless steel.

[0002]

2. Description of the Related Art There are various types of stainless steel produced by cold rolling, and the properties required for them are also various. For example, in spring material stainless steel, in addition to the performance required for general stainless steel, such as elongation, tensile strength, and proof stress, specific bendability and hardness are important as properties.

[0003] In cold rolling of stainless steel, usually, the rolling speed is increased in order to increase the productivity, and the rolling reduction is increased, so that the rolling is performed. On the other hand, in the production of certain types of rolled stainless steel, such as spring stainless steel, it is necessary to perform rolling under special conditions in order to satisfy properties required for products after rolling. Specifically, for example, it may be necessary to perform rolling at a low draft in a part of the rolling process.

[0004] Under such a low rolling reduction, there is no problem such as seizure, but the contact ratio between the material and the work roll in the contact arc is reduced, so that the roll coating becomes uneven in the width direction of the work roll. Easier to do. The coating unevenness causes uneven gloss on the plate surface after rolling by the transfer. The occurrence of such gloss unevenness is a major problem for stainless steel requiring high quality surface properties.
Conventionally, in order to reduce gloss unevenness in rolling at such a low rolling reduction, the rolling speed is slowed to increase the contact ratio even slightly, but slowing the rolling speed reduces productivity. It has the great disadvantage of lowering it.

[0005] As a method for preventing the occurrence of gloss unevenness other than slowing down the rolling speed, there are conceivable methods such as lowering the viscosity of the rolling oil and lowering the amount of the oil agent added. However, when any of these methods is employed, there is a high possibility that heat scratches will occur in any pass under severe rolling conditions, and it is difficult to employ these methods in practice.

Accordingly, there is a need for a development of a rolling oil which does not cause seizure or heat scratch at a high reduction rate, and does not cause uneven gloss even when the rolling speed is increased at a low reduction rate.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide cold rolling for stainless steel which does not cause seizure or heat scratch at high pressure reduction and does not cause uneven gloss even when the rolling speed is increased at low reduction. To provide oil.

[0008]

According to the present invention, the following formula is provided.
(I)

[0009]

Embedded image

(Wherein R ¹ and R ² are the same or different and represent a hydrocarbon group having 3 to 5 carbon atoms, and n represents a number of 4 to 8) for stainless steel containing a diester represented by the following formula: Cold rolling oil is provided.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The cold rolling oil for stainless steel of the present invention contains a diester represented by the above formula (I).

In the above formula (I), R ¹ and R ² are the same or different groups and are a hydrocarbon group having 3 to 5 carbon atoms. R ¹ ,
By setting the carbon number of R ² to 3 or more, it is possible to give a cold rolling oil for stainless steel having a high heat scratch occurrence limit, and by setting the carbon number to 5 or less, it is difficult to generate gloss unevenness on the plate surface after rolling. Cold rolling oil can be given. In the formula (I), n represents a number of 4 to 8. When n is larger than 8, uneven gloss is generated. On the other hand, if n is smaller than 4, image sticking is likely to occur under conditions of high rolling reduction. Of these, the availability of raw materials,
From the viewpoint of price and price, n = 4 and 6 are particularly preferable.

As R ¹ and R ² of the diester in the cold rolling oil for stainless steel of the present invention, an alkyl group, an alkenyl group and the like can be used, and among them, an alkyl group is preferable. As the alkyl group, a linear or branched one can be used, and a mixture of a linear and branched one can be used, but a branched one is preferred. Specific examples of R ¹ and R ² include a linear or branched propyl group, a linear or branched butyl group, and a linear or branched pentyl group.

Although the content of the diester in the cold rolling oil for stainless steel of the present invention is not particularly limited, good effects are obtained with respect to image sticking and heat scratching, and it is difficult to generate uneven gloss on the plate surface after rolling. In terms of that, usually 1% by mass or more and 99% by mass or less, preferably 2% by mass
To 75% by mass, more preferably 3% to 60% by mass.

The diester represented by the formula (I) is a straight-chain saturated dicarboxylic acid having 6 to 10 carbon atoms (adipic acid, pimelic acid, corucic acid, azelaic acid, sebacic acid) or a derivative thereof. And an alcohol having 3 to 5 carbon atoms can be obtained by any method such as esterification.

The cold rolling oil for stainless steel of the present invention preferably contains an alcohol in addition to the specific diester. By containing alcohol, seizure,
Not only a better effect on heat scratch can be obtained, but also the surface gloss can be further improved.

The alcohol is not particularly limited, but is preferably an alcohol having 12 to 18 carbon atoms from the viewpoints of fluidity and solubility in rolling oil in winter, heat resistance, and working environment. It is preferred to include. Specific examples include various types of saturated alcohols or unsaturated alcohols, and both saturated alcohols and unsaturated alcohols can be used favorably.
It is preferable to use a straight-chain alcohol and a branched alcohol in combination from the viewpoint of workability such as odor and heat scratch resistance. The proportion occupied by linear chains is usually from 40 to 90% by mass, preferably from 35 to 90% by mass, and preferably from 40 to 90% by mass, based on the total amount of alcohol having 12 to 18 carbon atoms.
80% by mass, more preferably 50% by mass to 70% by mass
It is. Specific examples of the saturated alcohol include, for example, linear or branched dodecanol, linear or branched tridecanol, linear or branched tetradecanol,
Examples thereof include linear or branched pentadecanol, linear or branched hexadecanol, and mixtures thereof.

Examples of the unsaturated alcohol include linear or branched decenol, linear or branched undecenol, linear or branched dodecenol, linear or branched tridecenol, linear or branched tridecenol, and linear or branched tridecenol. Examples include branched tetradecenol, linear or branched pentadecenol, linear or branched hexadecenol, linear or branched heptadecenol, linear or branched octadecenol, and the like.

When the rolling oil of the present invention contains alcohol, the content ratio of the alcohol is not particularly limited. However, from the viewpoint of heat scratch prevention performance and surface gloss, the rolling oil generally contains 1% by mass or more and 20% by mass or less, preferably 1% by mass or less. 2 to 15% by mass, more preferably 3 to 12% by mass
% By mass or less.

The cold rolling oil for stainless steel of the present invention may contain a base oil in addition to the specific diester and alcohol.

The viscosity of the base oil is not particularly limited.
Generally, the kinematic viscosity at 40 ° C. is 1 to ²⁰ mm ² /
s is preferred, and those in the range of ^{2 to} 15 mm ² / s are more preferred.

The naphthene content of the base oil is not particularly limited, but is preferably at least 10%, preferably at least 15%, more preferably at least 20%. Further, it is desirable that the content be 80% or less, preferably 70% or less, and more preferably 65% or less.

The paraffin content of the base oil is not particularly limited, but is preferably at least 10%, preferably at least 15%, more preferably at least 20%. Further, it is desirable that the content be 90% or less, preferably 85% or less, and more preferably 80% or less.

In the present invention, the ratios of naphthene and paraffin are determined based on the molecular ionic strength obtained by mass spectrometry using FI ionization (using a glass reservoir). Hereinafter, the measurement method will be specifically described. An adsorption tube for elution chromatography having a diameter of 18 mm and a length of 980 mm is filled with 120 g of silica gel (grade 923, manufactured by Fuji Devison Chemical Co., Ltd.) activated at about 175 ° C. for 3 hours and dried for 3 hours. Inject 75 ml of n-pentane and pre-wet the silica gel. About 2 g of a sample is precisely weighed, diluted with an equal volume of n-pentane, and the obtained sample solution is injected. When the liquid surface of the sample solution reaches the upper end of the silica gel, n-pentane 140 m is used to separate saturated hydrocarbon components.
and collect the eluate from the lower end of the adsorption tube. The solvent is distilled off from the eluate by a rotary evaporator to obtain a saturated hydrocarbon component. The type analysis of the saturated hydrocarbon component obtained in the above is performed by a mass spectrometer. As an ionization method in mass spectrometry, FI ionization using a glass reservoir is used, and a mass spectrometer is JMS-AX505 manufactured by JEOL Ltd.
Use H.

The measurement conditions are shown below.

Acceleration voltage: 3.0 kV Cathode voltage: -5 to -6 kV Resolution: about 500 Emitter: carbon Emitter current: 5 mA Measurement range: mass number 35 to 700 Sub Oven temperature: 300 ° C. Separator temperature: 300 ° C. Main Oven temperature : 350 ° C. Sample injection amount: 1 μl of molecular ions obtained by mass spectrometry, paraffins (C _n H _{2n + 2} ) were obtained from their mass numbers after isotope correction.
And naphthenes _{(C n H 2n, C n} H 2n-2, C n H 2n-4 ···)
The two types are classified and arranged, the fraction of each ionic strength is determined, and the content of each type with respect to the entire saturated hydrocarbon component is determined. Next, based on the content of the saturated hydrocarbon component obtained in the above, the respective contents of the paraffin component and the naphthene component with respect to the entire sample are determined.

The details of the data processing by the type analysis method of the FI method mass spectrometry are described in “Nisseki Review” Vol.
No. 135-142, especially "2.2.3 Data processing"
Section.

The aromatic content of the base oil is not particularly limited, but is preferably 25% by volume or less, preferably 20% by volume or less, and more preferably 15% by volume or less. Here, the aromatic component means a value which represents a value measured by applying the fluorescent indicator adsorption method of JIS K 2536 "Petroleum products-hydrocarbon type test method".

As the base oil, mineral oil, fat, synthetic oil, or a mixture of two or more thereof can be used.

As the mineral oil, solvent is removed from a lubricating oil fraction obtained by atmospheric distillation and vacuum distillation of crude oil,
Solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrorefining, sulfuric acid washing, paraffin-based or naphthenic-based obtained by appropriately combining two or more purification means such as clay treatment Mineral oils can be mentioned.

Examples of the fats and oils include beef tallow, lard, soybean oil, rapeseed oil, rice bran oil, coconut oil, palm oil, palm kernel oil, and hydrogenated products thereof.

As the synthetic oil, for example, poly-α-
Olefin (ethylene-propylene copolymer, polybutene,
1-octene oligomer, 1-decene oligomer, and hydrides thereof), alkylbenzene, alkylnaphthalene, monoester (butyl stearate, octyl laurate), diester (ditridecyl glutarate, di-2-
Ethylhexyl adipate, diisodecyl adipate, ditridecyl adipate, di-2-ethylhexyl sepacate, polyester (such as trimellitate), polyol ester (trimethylolpropane caprylate, trimethylolpropaneperargonate, pentaerythritol-2-ethyl) Hexanoate, pentaerythritol pelargonate, etc.), polyoxyalkylene glycol, polyphenyl ether, dialkyl diphenyl ether, phosphate ester (such as tricresyl phosphate), fluorine-containing compound (perfluoropolyether, fluorinated polyolefin, etc.), Examples include silicone oil.

The cold-rolling oil for stainless steel of the present invention may contain, in addition to the specific diester, alcohol and base oil, other additives for further improving the excellent effects.

The other additives may include extreme pressure additives, antioxidants, rust inhibitors, defoamers, mist inhibitors, fatty acids, metal deactivators, viscosity index improvers, and the like. . Moreover, you may further contain other esters other than the said specific diester.

Examples of the extreme pressure additives include phosphorus compounds such as tricresyl phosphate, and organometallic compounds such as zinc dialkyldithiophosphate.

Examples of the antioxidant include a phenolic compound such as 2,6-di-tert-butyl-P-cresol (DBPC), an aromatic amine such as phenyl-α-naphthylamine, and an organic metal such as zinc dialkyldithiophosphate. Compounds can be exemplified.

Examples of the rust inhibitor include salts of fatty acids such as oleic acid, sulfonates such as dinonylnaphthalenesulfonate, partial esters of polyhydric alcohols such as sorbitan monooleate, amines and derivatives thereof, phosphates and the like. Examples thereof include derivatives thereof.

Examples of the defoaming agent include silicon-based ones.

Examples of the mist preventive include copolymers of ethylene and propylene.

The fatty acids include monobasic acids and polybasic acids.

As the above-mentioned monobasic acid, a fatty acid having 6 to 24 carbon atoms can be usually used, and it may be linear or branched, and may be saturated or unsaturated.
Specifically, for example, linear or branched hexanoic acid, linear or branched octanoic acid, linear or branched nonanoic acid, linear or branched decanoic acid, linear or branched Branched undecanoic acid, linear or branched dodecanoic acid, linear or branched tridecanoic acid, linear or branched tetradecanoic acid, linear or branched pentadecanoic acid, linear or Branched hexadecanoic acid, linear or branched octadecanoic acid, linear or branched hydroxyoctadecanoic acid, linear or branched nonadecanoic acid, linear or branched eicosanoic acid, linear Or saturated fatty acids such as branched heneicosanoic acid, linear or branched docosanoic acid, linear or branched tricosanoic acid, linear or branched tetracosanoic acid, linear or branched Branched hexenoic acid, linear or branched heptenic acid, linear or branched octenoic acid, linear or branched nonenic acid, linear or branched decenoic acid, linear or Branched undecenoic acid, linear or branched dodecenoic acid, linear or branched tridecenoic acid, linear or branched tetradecenoic acid, linear or branched pentadecenoic acid, linear or Branched hexadecenoic acid,
Linear or branched octadecenoic acid, linear or branched hydroxyoctadecenoic acid, linear or branched nonadecenoic acid, linear or branched eicosenoic acid, linear or branched heneicosene Acid, linear or branched docosenoic acid, linear or branched tricosenoic acid,
Examples include unsaturated fatty acids such as linear or branched tetracosenoic acids and mixtures thereof. Among them, especially saturated fatty acids having 8 to 20 carbon atoms, or 8 to 2 carbon atoms
Preference is given to zero unsaturated fatty acids, and mixtures thereof.

Examples of the polybasic acids include dibasic acids having 2 to 16 carbon atoms and trimellitic acid. 2 to 1 carbon atoms
The dibasic acid 6 may be linear or branched, and may be saturated or unsaturated. Specifically, for example, ethanedioic acid, propanedioic acid, linear or branched butanedioic acid, linear or branched pentanedioic acid, linear or branched hexanedioic acid, linear Or a branched or octane diacid, a straight or branched nonanedioic acid, a straight or branched decandioic acid, a straight or branched undecandioic acid, a straight or branched dodecane diacid Acid, linear or branched tridecandioic acid, linear or branched tetradecandioic acid, linear or branched heptadecandioic acid, linear or branched hexadecandioic acid, linear Or branched hexenedioic acid, linear or branched octenedioic acid, linear or branched nonenedioic acid, linear or branched decenedioic acid, linear or branched undecenedioic acid Acid, linear or branched dodecenedioic acid, straight Examples include linear or branched tridecene diacids, linear or branched tetradecene diacids, linear or branched heptadecenedioic acids, linear or branched hexadecene diacids, and mixtures thereof.

Examples of the metal deactivator include benzotriazole, organic sulfonates, phosphates, and olefin phosphorus sulfide.

Examples of the viscosity index depressant include polymethacrylate, polyisobutene, ethylene propylene copolymer and the like.

The other ester is a monoester.
(Butyl stearate, octyl laurate), diester
(Ditridecyl glutarate, di-2-ethylhexyl adipate, diisodecyl adipate, ditritesyl adipate, di-2-ethylhexyl sepacate, etc.), polyester
(Such as trimellitate).

The content of the other additives is usually not more than 20% by mass, preferably not more than 15% by mass in the total amount of the rolling oil.
% Is desirable.

The physical properties of the cold rolling oil for stainless steel of the present invention are not particularly limited.
Those having a range of 5 mm ² / s are preferable, and 3 to 12 m
Those in the range of m ² / s are more preferred. Such a desired viscosity can be easily obtained by appropriately adjusting the type, blending ratio and the like of the base oil.

The cold rolling oil for stainless steel of the present invention can be used for rolling at various rolling reductions. Specifically, it can be used for rolling at a middle / high pressure reduction rate of more than 30% and can be preferably used for rolling at a low reduction rate of 30% or less. Here, rolling with a rolling reduction of 30% or less refers to rolling in which the rolling reduction is 30% or less in all or a part of the rolling process. The cold rolling oil for stainless steel of the present invention is less likely to cause seizure, heat scratch, and uneven gloss even under such conditions. The cold-rolled oil for stainless steel of the present invention can be used for rolling various stainless rolled materials to produce rolled stainless steel. In particular, it can be preferably used as a stainless steel rolling material which requires rolling at a low rolling reduction. The stainless steel means a general stainless steel used without being limited to a spring material, and specifically, austenitic, martensitic, ferritic and other stainless materials, particularly SUS304, SUS420, SUS
430 or the like can be used as a rolling material for rolling. In the present invention, spring material stainless steel is JI
It is specified by SG4313 “Stainless steel strip for spring material”, and can be obtained by rolling a stainless steel such as SUS304 or SUS420 as a rolling material so as to satisfy a predetermined property.

[0049]

Since the cold rolling oil for stainless steel of the present invention contains a specific diester, it does not cause seizure or heat scratch at high pressure reduction, and uneven gloss even when the rolling speed is increased at low reduction. In the cold rolling of stainless steel in which the rolling reduction is varied without causing the reduction, it is possible to achieve both improvement in productivity and high quality of the rolled product.

[0050]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0051]

Examples 1 to 20 and Comparative Examples 1 to 6 Using the following rolled material and sample oil, a test for unevenness in gloss of the sample oil and a test for generating a heat scratch were performed under the following conditions.

As the rolling material, JIS SUS304 material (thickness 0.65 mm, width 100 mm) or JIS SUS420 material (thickness 0.65 mm, width 100 mm) was used.

The sample oil used had the following composition. All percentages of the composition are mass%. 1: 20% diisobutyl adipate, residual mineral oil 2: 20% diisopropyl adipate, residual mineral oil 3: 20% dipentyl corcolate residual mineral oil 4: 20% diisobutyl sebacate residual mineral oil 5: 35% diisobutyl adipate residual mineral oil 6: adipate Diisobutyl acid 50% remaining Mineral oil 7: Diisobutyl adipate 20%, n-dodecyl alcohol 6%, 2-methyl-1-undecyl alcohol 4% remaining
Mineral oil 8: 35% of diisobutyl adipate, 6% of n-dodecyl alcohol, 4% of 2-methyl-1-undecyl alcohol remaining
Mineral oil 9: Diisobutyl adipate 50%, n-dodecyl alcohol 6%, 2-methyl-1-undecyl alcohol 4% remaining
Mineral oil 10: Diisobutyl adipate 20%, n-dodecyl alcohol 3%, 2-methyl-1-undecyl alcohol 2% residual mineral oil 11: diisononyl adipate 20%, residual mineral oil 12: dindecyl adipate 20%, residual mineral oil 13: adipin Dimethyl acid 20%, residual mineral oil The mineral oil has a kinematic viscosity of 32 mm ² / sec at 40 ° C.
Base oil A (paraffin content: 64% by mass, naphthene content: 29% by mass, aromatic content: 7% by volume) and base oil B having a kinematic viscosity at 40 ° C. of 2.8 mm ² / sec. Mass%, naphthene content 28% by mass, aromatic content 7% by volume)
Were used in the proportions shown in Table 1 below, and the kinematic viscosity of each sample oil was adjusted to be 7.0 mm ² / sec (40 ° C.). In the table,% CP,% CN and% CA are paraffin content% by mass, naphthene content% by mass and aromatic content% by mass, respectively.
Represents

[0054]

[Table 1]

Using a work roll with a test diameter of 51 mm for gloss unevenness , a rolling speed of 150 m /
min, rolled 3 rolls of rolled material of 350m length at 13% reduction and 9 points in the width direction of the surface gloss value 20m before the third rolling end point (1cm interval from plate edge) It was measured and its standard deviation was determined. Heat scratch generation test Using a work roll with a diameter of 51 mm, rolling speed 75 m / min
Then, the rolling reduction was gradually increased from 10%, and the rolling reduction at which heat scratch began to occur was examined. The heat scratch was confirmed by observing the surface of the plate using an optical microscope (400 times) for those that could not be visually judged.

Tables 2 to 4 show the rolling materials and sample oils used in each of the examples and comparative examples, and the test results.

[0057]

[Table 2]

[0058]

[Table 3]

[0059]

[Table 4]

* "3" is SUS304, "4" is SUS
420 are shown. **: Standard deviation of gloss value at 9 points ***: Reduction rate at which heat scratch occurred% As described above, in the cold rolling oil for stainless steel of the present invention (Examples 1 to 20), the reduction rate was 20%. In the uneven gloss test, the uneven gloss did not almost completely occur, and the heat scratch generation test also showed good results, and a high heat scratch limit was obtained.

On the other hand, in the test results (Comparative Examples 1 to 6) in which the diester used is out of the range specified in the present invention, the uneven gloss and the limit of heat scratch occurrence are remarkably inferior to those of the examples. I was

Claims (3)

[Claims] 1. A compound represented by the following formula (I): (Wherein R ¹ and R ² are the same or different groups and each have 3 to 5 carbon atoms)
And n represents a number of 4 to 8. Cold rolled oil for stainless steel containing the diester represented by). 2. A spring material for rolling stainless steel.
The cold rolling oil for stainless steel described. 3. The cold rolling oil for stainless steel according to claim 1, which is used for rolling at a rolling reduction of 30% or less.