DE112009004308T5 - Lubricating oil for use in hot rolling oil and process for producing hot rolled sheet - Google Patents

Abstract

A lubricating oil for use in hot rolling oil for aluminum sheet includes: (a) a mineral oil with a kinematic viscosity of 80 mm2 / second or less at 40 ° C; (b) 1 to 14% by mass of a fatty acid having 10 to 22 carbon atoms; (c) 5 to 15% by mass of an oil and fat and / or a synthetic ester; (d) 5 to 10% by mass of a high pressure phosphorus agent; (e) 0.1 to 1% by mass of a polyoxyethylene alkylamine; and 0.1 to 10 mass% of an organic acid salt of a copolymer composed of a (meth) acrylic acid salt, (meth) acrylamide and at least one amine monomer, and the mass ratio of component (c) to component (d) (component (c) / Component (d)) is 1 / 0.6 to 1/1. The lubricating oil for use in hot rolling oil for aluminum sheet of the invention provides a high level of rolling lubricity, iron corrosion protection in a hot rolling step, and a rolled aluminum sheet with high surface quality of the sheet can be obtained.

Description

TECHNICAL AREA

The invention relates to a lubricating oil for use in hot rolling oil for aluminum sheet. The invention also relates to a hot rolling oil produced with the lubricating oil for use in hot rolling oil. The invention also relates to a method for producing a hot-rolled aluminum sheet with the hot rolling oil. For example, in the method of producing a hot-rolled sheet, the hot-rolling oil is used in a rough-rolling process in which band-rolling is performed. The term "aluminum sheet" from "for aluminum sheet", which refers to use in an embodiment of the invention, is intended to include "sheet of pure aluminum and / or sheet of aluminum alloy".

BACKGROUND OF THE TECHNIQUE

In general, an aluminum sheet is produced by a method of hot rolling a billet that has undergone melting, casting, planing, and homogenizing into a sheet, then optionally performing cold rolling, annealing, and conditioning steps on the sheet (such as a step of longitudinally splitting the sheet Sheet to a width of a suitable product size and a smooth flatness forming step) and optionally performing a surface treatment process. Among the manufacturing steps, the hot rolling step is the most important for the quality of the aluminum sheet product. The hot rolling step is carried out by using a method including performing rough rolling with a reverse type hot rolling mill and then performing finish rolling with a tandem type finish rolling mill, or a method of performing both roughing and finishing rolling with a single one Roll mill for both roughing and finish rolling includes performed.

When an aluminum sheet is hot rolled, aluminum is transferred from the surface of the sheet to be rolled to the surface of the rolling mill roll and deposited thereon to form a roll coating. Since the sheet being rolled is in contact with the roll coating, the surface quality of the rolled sheet depends on the properties of the roll coating. Surface defects formed on a plate during hot rolling also affect the surface quality after cold rolling, which also means that roll coating properties during hot rolling are very important. Roll coating properties vary with different rolling conditions (such as sheet metal, sheet temperature, sheet surface roughness, roll temperature, roll surface roughness, roll reduction, rolling speed and brush roll process conditions) and hot rolling oil. Therefore, the selection of hot rolling oil is indispensable for regulating the roll coating.

Hot rolling oil is used in the form of an emulsion because hot rolling requires sufficient roll cooling performance. Properties required of aluminum sheet hot rolling oil include rolling smoothness, roll coating properties, sheet surface quality, emulsion stability, iron corrosion protection, etc. Conventionally, conventional aluminum sheet hot rolling oil is used in the form of an emulsion prepared by mixing mineral oil as a lubricating base oil with a lubricity improver such as a fatty acid, natural oil and fat or a fatty acid ester, and other additives such as an extreme pressure agent, a corrosion inhibitor and an antioxidant, and emulsifying the mixture generally with an anionic surfactant.

Unfortunately, in conventional hot rolling oil for aluminum sheet produced with an emulsifier, rolling smoothness and emulsion stability tend to cancel each other out, and it is impossible to obtain a satisfactory level of both performances. In particular, as the rolling smoothness increases, the emulsion stability decreases, so that the stability of rolling smoothness also decreases over time, causing a problem with the stability of the aluminum sheet surface quality. On the other hand, as the emulsion stability increases, rolling smoothness can not be sufficiently obtained, so that various defects are formed on aluminum sheet surfaces.

In order to ensure such mutually incompatible properties, including rolling smoothness, emulsion stability and sheet surface quality, at the same time, a hot rolling oil composition including a combination of a specific lubricating oil component and a specific water-soluble cationic polymer compound (Patent Document 1) is proposed. It will also be a hot rolling oil proposed in which a specific lubricating oil component is used in combination with an anionic surfactant and a nonionic surfactant (Patent Document 2).

DOCUMENTS OF THE STATE OF THE ART

Patent documents

• Patent Document 1: JP No. 2869850
• Patent Document 2: JP No. 2990021

DISCLOSURE OF THE INVENTION

Problems to be solved by the invention

In recent years, rolled aluminum products of high quality and low cost have been demanded, and therefore there is a demand for hot rolling oil which makes it possible to obtain more stable rolling lubricity and sheet surface quality. For example, a study has been made on methods for producing mainly 3xxx aluminum alloy based materials for beverage can bodies or the like, or 1xxx pure aluminum for printing plates or the like omitting box-annealing annealing and a manufacturing method in which the aluminum structure , which regulates the formability of aluminum sheet products or the appearance characteristics of aluminum sheet products after the surface treatment is optimized by a hot rolling method in place of an annealing method so that the quality characteristics can also be improved, is gradually becoming the main method. An adequate structure should be formed in the hot rolling process so that an adequate structure can be formed in the final products. For this purpose, the hot rolling conditions become hard because high reduction techniques or high elongation rate techniques or the like are required as compared with conventional techniques, and therefore likely surface anomalies such as seizure tend to occur due to insufficient lubricity. Therefore, the hot rolling oil to be used is required to have higher lubricity than conventional oils. If the lubricity of the hot rolling oil can be improved, a reduction in the number of pre-hot rolling passes or an increase in productivity by increasing the rolling speed can be expected even when using high-Mg-content aluminum alloy sheets (5xxx aluminum alloys such as 5182 aluminum alloy for beverage can lids), which have a high resistance to deformation and therefore make it conventionally difficult to reduce the number of pre-hot rolling passes due to insufficient lubricity. On the other hand, when the aluminum material to be rough-rolled has low deformation resistance, care should be taken that the gripping performance is not deteriorated, particularly that the performance in gripping a pure aluminum sheet whose friction coefficient during rolling is low is not deteriorated. Therefore, it is also required that hot rolling oil for aluminum sheet satisfies these mutually incompatible requirements.

According to Patent Document 1, the amount of a fatty acid which is one of the lubricating oil components and serves as a lubricity improving agent can be increased. However, when the content of the fatty acid in the hot rolling oil composition increases to 15 mass% or more, there will occur a problem in which the fatty acid has a considerably high degree of corrosiveness, and there will be another problem in which a metal soap which is a material of high viscosity, as the rolling progresses, so that the area around the rolling mill is contaminated with the metal soap.

Patent Document 2 proposes a technique for improving rolling smoothness with no deterioration in iron corrosion protection in which hot rolling oil having improved rolling lubricity is produced by using a relatively large amount of natural oil and fat and / or a synthetic ester, so that the content of a Fatty acid can be limited. However, in a rough rolling process in which strip rolling is performed, an increase in rolling lubricity may lead to reductions in gripping performance and operational performance. In addition, the proposed technique does not improve the surface quality of aluminum alloy sheets.

An object of the invention is to provide a lubricating oil for use in hot rolling oil for aluminum sheet, which provides a high level of rolling lubricity, iron corrosion protection and gripping performance, and makes it possible to obtain a rolled aluminum sheet with high surface quality of the sheet. even under hard hot rolling conditions where the reduction and / or strain rate is set high compared to conventional methods.

Another object of the invention is to provide a hot rolling oil produced with the lubricating oil for use in hot rolling oil. Another object of the invention is to provide a method for producing a hot rolled aluminum sheet with the hot rolling oil.

Means of solving the problems

• (a) ein Mineralöl mit einer kinematischen Viskosität von 80 mm²/Sekunde oder weniger bei 40°C;
• (b) 1 bis 14 Masse-% einer Fettsäure mit 10 bis 22 Kohlenstoffatomen;
• (c) 5 bis 15 Masse-% eines Öls und Fetts und/oder eines synthetischen Esters;
• (d) 5 bis 10 Masse-% eines phosphorhaltigen Hochdruckmittels;
• (e) 0,1 bis 1 Masse-% eines Polyoxyethylenalkylamins; und
• (f) 0,1 bis 10 Masse-% eines organischen Säuresalzes eines aus einem (Meth)acrylsäuresalz, (Meth)acrylamid und mindestens einem Aminmonomer zusammengesetzten Copolymers, dargestellt durch Formel (1):

[Formel 2]

wobei R¹ ein Wasserstoffatom oder eine Methylgruppe bedeutet, R² und R³ die gleichen oder verschiedene Alkylreste mit 1 bis 3 Kohlenstoffatomen bedeuten, A -NH- bedeutet und m eine ganze Zahl von 1 bis 3 bedeutet, wobei
das organische Säuresalz des Copolymers ein Gewichtsmittel des Molekulargewichts von 10.000 bis 1.000.000 aufweist,
eine zur Bildung des organischen Säuresalzes des Copolymers verwendete organische Säure durch Formel (2) dargestellt ist: R⁴COOH,
wobei R⁴ einen Alkylrest mit 1 bis 5 Kohlenstoffatomen, einen Hydroxyalkylrest mit 1 bis 5 Kohlenstoffatomen, einen Carboxyalkylrest mit einer Alkyleinheit mit 1 bis 5 Kohlenstoffatomen oder eine Carboxylgruppe bedeutet, und
das Massenverhältnis der Komponente (c) zur Komponente (d) (Komponente (c)/Komponente (d)) 1/0,6 bis 1/1 beträgt.In particular, the invention is directed to a lubricating oil for use in hot rolling oil for aluminum sheet, which includes:

• (a) a mineral oil having a kinematic viscosity of 80 mm ² / second or less at 40 ° C;
• (b) 1 to 14% by mass of a fatty acid having 10 to 22 carbon atoms;
• (c) 5 to 15% by weight of an oil and fat and / or a synthetic ester;
• (d) 5 to 10% by weight of a high pressure phosphorus-containing agent;
• (e) 0.1 to 1% by weight of a polyoxyethylene alkylamine; and
• (f) 0.1 to 10 mass% of an organic acid salt of a copolymer composed of a (meth) acrylic acid salt, (meth) acrylamide and at least one amine monomer represented by formula (1):

[Formula 2]

wherein R ^{1 is} a hydrogen atom or a methyl group, R ² and R ^{3 are} the same or different alkyl radicals having 1 to 3 carbon atoms, A is -NH- and m is an integer from 1 to 3, wherein
the organic acid salt of the copolymer has a weight average molecular weight of 10,000 to 1,000,000,
an organic acid used to form the organic acid salt of the copolymer represented by formula (2): R ⁴ COOH,
wherein R ^{4 is} an alkyl group having 1 to 5 carbon atoms, a hydroxyalkyl group having 1 to 5 carbon atoms, a carboxyalkyl group having an alkyl group having 1 to 5 carbon atoms or a carboxyl group, and
the mass ratio of the component (c) to the component (d) (component (c) / component (d)) is 1 / 0.6 to 1/1.

The invention is also directed to an aluminum sheet hot rolling oil including the above lubricating oil for use in hot rolling oil and water.

The invention also aims at a method for producing a hot rolled sheet including a step of hot rolling an aluminum sheet in the presence of the above aluminum sheet hot rolling oil.

Effects of the invention

In a hot rolling step of a production method of an aluminum sheet, particularly a roughing step in which strip rolling is performed, the hot rolling oil provided with the lubricating oil for use in hot rolling oil for aluminum sheet of the invention (hereinafter referred to as "the lubricating oil for use in hot rolling oil of the invention") Providing a high level of rolling lubricity and iron corrosion protection, it maintains the gripping performance and makes it possible to obtain a rolled aluminum sheet with high surface quality of the sheet, even under hard Hot rolling conditions where the reduction and / or strain rate is set high compared to conventional methods.

The hot rolling oil composition disclosed in Patent Document 1 also contains components equal to those of the lubricating oil for use in hot rolling oil of the invention. However, the hot rolling oil composition disclosed in Patent Document 1 does not fully meet the demands for the recent demand for high quality and low cost products under hard hot rolling conditions where the reduction and / or strain rate for the production of high quality and low quality products Cost is set high, although it can to some extent ensure both rolling smoothness and surface quality of the sheet under conventional aluminum sheet hot rolling conditions. In general, the amount of an oil and fat or a synthetic ester can be increased, so that the rolling lubricity can be improved. However, as the amount of the oil and fat or the synthetic ester is increased, the friction coefficient decreases, and in particular, the performance in gripping a pure aluminum sheet deteriorates. The high-pressure phosphorus-containing agent can not increase the surface quality of the sheet with no increase in rolling lubricity, but the high-pressure phosphorus-containing agent is expensive and therefore can not be used in a large amount. The fatty acid is effective for rolling smoothness and surface quality of the sheet, but it deteriorates the iron corrosion protection when used in a large amount. Thus, the content of each component in the lubricating oil is limited for use in hot rolling oil. The lubricating oil for use in hot rolling oil of the invention contains components similar to those of the hot rolling oil composition disclosed in Patent Document 1. In the lubricating oil for use in hot rolling oil of the invention, however, the content of the oil and fat or the synthetic ester and the content of the phosphorus-containing extreme pressure agent or the like are not increased, whereas the content of the oil and fat or the synthetic ester is regulated it is equal to or slightly higher than the content of the phosphorus-containing high pressure agent, so that the lubricating oil for use in hot rolling oil of the invention ensures both rolling smoothness and surface quality of the sheet, and also a satisfactory level of iron corrosion protection and gripping performance even under hard hot rolling conditions where Reduction and / or the strain rate for the production of aluminum sheets with high-level features that have been demanded in recent years, set high.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

In the lubricating oil for use in hot rolling oil of the invention, the mineral oil as the component (a) is typically a spindle oil, a machine oil, a turbine oil, a cylinder oil, a neutral oil or the like. In terms of heat resistance and rolling lubricity, these mineral oils are more preferably paraffinic mineral oils. The mineral oil to be used has a viscosity of 80 mm ² / second or less at 40 ° C. If the viscosity exceeds 80 mm ² / second, the surface quality of the sheet may decrease. Component (a) is a base oil of the lubricating oil for use in hot rolling oil of the invention. The component (a) to be used may be a single oil or a combination of two or more oils. Although the content of the component (a) in the entirety of the lubricating oil for use in hot rolling oil is 88.8 mass% or less, it is preferably 51 to 88.8 mass%, more preferably 60 to 85 mass%, even more preferably 65 to 80% by mass in view of rolling lubricity, iron corrosion protection, surface quality of the sheet or gripping performance.

The fatty acid having 10 to 22 carbon atoms as the component (b) may be capric, lauric, stearic, isostearic, oleic, erucic, palm oil or the like. From the viewpoint of rolling smoothness, emulsion stability, iron corrosion protection or surface quality of the sheet, the fatty acid preferably has 10 to 20 carbon atoms, more preferably 13 to 20 carbon atoms, more preferably the fatty acid is 13 to 20 carbon unsaturated or branched fatty acid. The component (b) functions as a lubricity improving agent which may be a single fatty acid or a combination of two or more fatty acids. With respect to emulsion stability, oleic acid and isostearic acid are preferable, and oleic acid is more preferable since they are liquid at room temperature and unpredictable. The content of the component (b) in the entirety of the lubricating oil for use in hot rolling oil of the invention is 1 to 14% by mass, preferably 2 to 12% by mass, more preferably 4 to 10% by mass. Regulating the content of the component (b) in the above range is preferred in view of rolling smoothness, emulsion stability, iron corrosion protection or surface quality of the sheet.

An oil and fat and / or a synthetic ester is used as the component (c). The oil and fat is a naturally occurring ester and the synthetic ester is an artificially produced ester. Examples of the oil and fat include animal and vegetable oils and fats such as whale oil, beef tallow, lard, rapeseed oil, castor oil, palm oil and coconut oil. The synthetic ester may be a synthetic ester (1) derived from a fatty acid and a monohydric or polyhydric alcohol. The fatty acid may be a fatty acid of 10 to 22 carbon atoms, examples of which include those listed for component (b) and fatty acids derived from the oils and fats. The monohydric alcohol may be a monohydric fatty alcohol having 1 to 22 carbon atoms. In view of the surface quality of the sheet, a fatty alcohol having 1 to 15 carbon atoms is preferable and becomes More preferred is fatty alcohol of 1 to 8 carbon atoms. Examples of the polyhydric alcohol include ethylene glycol, trimethylolpropane, pentaerythritol and glycerin. The synthetic ester (1) is preferably a fatty acid monoester, examples of which include methyl caprate, butyl stearate, laurate oleate, 2-ethylhexyl erucate, pentaerythritol monooleate, and glycerol monooleate. The synthetic ester may also be a synthetic ester (2) derived from a fatty alcohol and a monobasic or polybasic acid. The fatty alcohol may be a fatty alcohol having the same number of carbon atoms as the fatty acid having 10 to 22 carbon atoms. In view of the surface quality of the sheet, a fatty alcohol having 10 to 20 carbon atoms is preferable, and a fatty alcohol having 12 to 18 carbon atoms is more preferable. Examples of the polybasic acid include phthalic acid, trimellitic acid, adipic acid and sebacic acid. Examples of the synthetic ester (2) include dilauryl phthalate, tri-2-ethylhexyl trimellitate, diisodecyl adipate and dioleyl sebacate. The component (c) to be used may be a single ester or a combination of two or more esters. With respect to the surface quality of the sheet, the component (c) is preferably the synthetic ester, more preferably the synthetic ester (1), still more preferably a fatty acid monoester, still more preferably butyl stearate. The component (c) functions as an agent for improving the lubricity and the content of the component (c) in the entirety of the lubricating oil for use in hot rolling oil of the invention is preferably 5 to 15 mass%, more preferably 6 to 15 mass%. , Regulating the content of the component (c) in the above range is preferred in view of rolling smoothness, surface quality of the sheet or gripping performance.

High pressure agent provides rolling smoothness without reducing the coefficient of friction during rolling. Examples of the high pressure phosphorus-containing component (d) include alkyl or alkenyl phosphates or alkyl or alkenyl phosphites. In view of the rolling lubricity and surface quality of the sheet, the phosphorus-containing extreme pressure agent is preferably an alkyl or alkenyl phosphate or an alkyl or alkenyl phosphite. The alkyl or alkenyl group of the phosphate or phosphite may have 4 to 18 carbon atoms, and examples of the phosphate and the phosphite include dibutyl phosphate, monooctyl phosphate, trioleyl phosphate, tricresyl phosphate, tributyl phosphite, diisooctyl phosphite, trioleyl phosphite and triisooctyl phosphite. With regard to the surface quality of the sheet, the number of carbon atoms is preferably 4 to 15, more preferably 4 to 8. The phosphate or phosphite may be a monoester, diester or triester. With regard to iron corrosion protection, an alkyl or alkenyl acid phosphate or an alkyl or alkenyl acid phosphite which is a triester is preferred. The component (d) to be used may be a single agent or a combination of two or more agents. The content of the component (d) in the entirety of the lubricating oil for use in hot rolling oil of the invention is preferably 5 to 10 mass%, more preferably 6 to 10 mass%, even more preferably 8 to 10 mass%. Regulating the content of the component (d) in the above range is preferable in view of rolling smoothness or surface quality of the sheet.

Component (c) and component (d) are used in a mass ratio component (c) / component (d) of 1 / 0.6 to 1/1. The mass ratio is preferably 1 / 0.7 to 1/1, more preferably 1 / 0.8 to 1/1. Regulating the ratio of the component (c) to the component (d) in the above range is preferable in terms of surface quality of the sheet and gripping performance.

The polyoxyethylene alkylamine as the component (e) may be a compound represented by formula (3): R ⁵ -NH- (EO) _n -H or formula (4): H- (EO) _n1 -NR ⁶ - (EO) _n2 -H is shown, wherein R ⁵ and R ⁶ are each an alkyl radical having 10 to 18 carbon atoms, preferably an alkyl radical having 10 to 16 carbon atoms, more preferably an alkyl group having 12 to 14 carbon atoms in terms of emulsion stability and iron corrosion protection mean EO a Oxyethylenrest n, n1, and n2 each represents an average addition mol number of EO, n is preferably 2 to 10, more preferably 2 to 8, still more preferably 2 to 5 in view of emulsion stability and iron corrosion protection, n1 and n2 are each 1 or more and n1 + n2 is preferably 2 to 10, more preferably 2 to 8, even more preferably 2 to 5 in view of emulsion stability and iron corrosion protection. Component (e) acts as a corrosion inhibitor. The component (e) to be used may be a single compound or a combination of two or more compounds. With regard to emulsion stability and iron corrosion protection, component (e) is preferably polyoxyethylene laurylamine. The content of the component (e) in the entirety of the lubricating oil for use in hot rolling oil of the invention is 0.1 to 1 mass%, preferably 0.2 to 1 mass%, more preferably 0.4 to 1 mass%. Regulating the content of the component (e) in the above range is preferred in view of emulsion stability or iron corrosion protection. With regard to emulsion stability and iron corrosion protection, component (e) preferably has an HLB of 6 to 13, more preferably 10 to 13.

The organic acid salt of the copolymer as the component (f) is an organic salt composed of a copolymer of an amine monomer represented by formula (1), (meth) acrylamide and a (meth) acrylic acid salt. The term "(meth) acrylamide" refers to acrylamide and / or methacrylamide and the term "(meth) acrylic acid salt" refers to acrylic acid salt and / or methacrylic acid salt. In the specification, "(meth)" has the same meaning as mentioned above. In the copolymer of the amine monomer represented by formula (1), (meth) acrylamide and the (meth) acrylic acid salt, the molar ratio (amine monomer: (meth) acrylamide: (meth) acrylic acid salt) is preferably 50-90: 0.1 -20: 10-50, more preferably 59-90: 1-10: 10-30, even more preferably 69-90: 1-5: 10-25 in terms of emulsion stability.

Examples of the amine monomer represented by formula (1) include dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide and diethylaminomethyl (meth) acrylamide. Among the examples, dimethylaminopropylmethacrylamide and diethylaminopropylacrylamide are preferred in view of emulsion stability.

Examples of the (meth) acrylic acid salt include (meth) acrylic acid alkali metal salt, such as sodium salt of (meth) acrylic acid and potassium salt of (meth) acrylic acid, and (meth) acrylic acid organic amine salt, such as monoethanolamine salt of (meth) acrylic acid, diethanolamine salt of (meth) acrylic acid and triethanolamine salt of (meth) acrylic acid.

The organic acid used to form the organic acid salt of the copolymer as the component (f) includes a compound represented by formula (2): R ⁴ COOH, which provides R ⁴ COO ^- , whereby an organic acid salt having the amino group of Amine monomer, which is represented by formula (1) is formed. Examples of R ⁴ in the formula include an alkyl group having 1 to 5 carbon atoms, a hydroxyalkyl group having 1 to 5 carbon atoms, a carboxyalkyl group having an alkyl group having 1 to 5 carbon atoms, and a carboxyl group. With respect to emulsion stability, R ^{4 is} preferably a methyl group or a hydroxyalkyl group having 1 to 5 carbon atoms. Examples of R ⁴ COO ^- include the acetate, propionate, Butyration, Valeration, Caproation, Glycolation, Lactation, Hydroacrylation, oxalate ion, Malonation, succinate, Glutaration and Adipation. Among them, acetate ion, glycolation, lactation and hydroacrylation are preferred, and acetate ionization and glycolation are more preferable in view of emulsion stability.

The organic acid salt of the copolymer as the component (f) preferably has a weight average molecular weight in the range of 10,000 to 1,000,000, more preferably in the range of 30,000 to 300,000. If it has a weight average molecular weight in the above range, the organic acid salt provides good emulsion stability and has good handleability. The weight-average molecular weight can be determined by a method, adding 10 ml of 0.5 M sodium hydroxide to 1 g of the organic acid salt of the copolymer, allowing the mixture to stand at 95 ° C for 2 hours to conduct hydrolysis, then measuring the Molecular weight by GPC (gel permeation chromatography) and calculating the molecular weight before hydrolysis on the basis of the result. More specifically, the GPC conditions are as follows:
Column: α-M × 2 (manufactured by TOSOH CORPORATION)
Column temperature: 40 ° C
Eluent: 0.15 M sodium sulfate, 1% aqueous acetic acid solution
Detector: RI (differential refractometer)
Injection volume: 0.5% (w / v) aqueous eluent solution, 100 μl
Flow rate: 1.0 ml / min
Molecular Weight Standard: Pullulan (manufactured by SHODEX Inc.) (four standards of 788,000, 194,000, 46,700 and 5,900)

For example, the organic acid salt of the copolymer as the component (f) can be obtained by neutralizing the produced copolymer with the organic acid of the formula (2) or by previously treating the amine monomer represented by the formula (1) with the organic acid of the formula (2) is neutralized in the preparation of the copolymer.

The component (f) to be used may be a single salt or a combination of two or more salts. The content of the component (f) in the entirety of the lubricating oil for use in hot rolling oil of the invention is 0.1 to 10% by mass, preferably 0.4 to 5% by mass, more preferably 0.6 to 3% by mass. Regulating the content of the component (f) in the above range is preferable in view of rolling smoothness or surface quality of the sheet.

In addition to the above components, the lubricating oil for use in hot rolling oil of the invention may further contain, if necessary, known additives such as a corrosion inhibitor, an antioxidant and an emulsifier for improving the initial emulsifiability.

Examples of the anticorrosion agent that can be used include alkenyl succinate and derivatives thereof, fatty acids such as oleic acid, esters such as sorbitan monooleate, and other amines. The content of the anticorrosion agent in the entirety of the lubricating oil for use in hot rolling oil of the invention is preferably 0.2 to 2% by mass, more preferably 0.5 to 1.5% by mass.

Examples of the antioxidant that can be used include phenolic compounds such as 2,4-di-tert-butyl-p-cresol, and aromatic amines such as phenyl-α-naphthylamine. The antioxidant is preferably added in an amount of 0.2 to 5% by mass, more preferably 0.5 to 1.5% by mass, based on the total mass of the lubricating oil for use in hot rolling oil of the invention.

Examples of the emulsifier which can be used include anionic surfactants such as triethanolamine salt of oleic acid and sodium petroleum sulfonate, and nonionic surfactants such as polyoxyethylene lauryl ether. The content of the emulsifier is preferably 2% by mass or less, more preferably 1% by mass or less, based on the total mass of the lubricating oil for use in hot rolling oil of the invention.

The lubricating oil for use in hot rolling oil of the invention is diluted with water when it is used to produce a hot rolling oil. The water dilution is a hot rolling oil emulsion (O / W type emulsion) containing the lubricating oil dispersed in water for use in hot rolling oil of the invention. The dilution rate with water to produce the dilution of water is not limited. In general, the concentration of the lubricating oil for use in hot rolling oil of the invention in the water dilution is preferably 1 to 30% by mass, more preferably 2 to 15% by mass. In the hot rolling oil emulsion, the emulsion particles preferably have a volume average particle size of 1 to 20 μm, more preferably 5 to 15 μm from the viewpoint of rolling smoothness and emulsion stability.

The hot rolling oil of the invention is intended to be used in the method of rolling an aluminum sheet with a hot rolling mill in a method of producing a hot rolled sheet. The rolling process can be carried out using conventional methods (see, for example "Keikinzoku no Kenkyu to Gijutsu no Ayumi" (History of Light Metal Research and Technology), published November 30, 1991 by The Japan Institute of Light Metals) for which examples include a rough rolling process in which strip rolling is performed and a finish rolling process in which coil rolling is performed. A commonly used system for supplying rolling oil (see, for example, "Keikinzoku no Kenkyu to Gijutsu no Ayumi" (History of Light Metal Research and Technology), published on November 30, 1991 by The Japan Institute of Light Metals) can be used in a feeding method of the hot rolling oil of the invention are used in the hot rolling process, and examples of such a process include methods of applying an emulsion of the hot rolling oil to a roller mill roll with a spray or the like. More specifically, the method of the invention for producing a hot rolled sheet includes the step of hot rolling an aluminum sheet in the presence of the aluminum sheet hot rolling oil of the invention. The method described above may be used to feed the aluminum sheet hot rolling oil of the invention to the hot rolling step.

EXAMPLES

Examples 1 to 8 and Comparative Examples 1 to 6

Hot rolling oils (O / W type emulsions) having a concentration of 2% by mass were prepared under the conditions described below using water and various lubricating oils for use in hot rolling oil having the compositions listed in Table 1 for hot rolling oils. The hot rolling oil of Comparative Example 3 corresponds to the blend No. 3 in Examples according to the invention disclosed in Patent Document 1.

(Conditions for the production of hot rolling oil emulsions)

• Fluid temperature: 60 ° C
• Mixer: M-type homomixer (manufactured by PRIMIX Corporation)
• Number of revolutions: 8,000 rpm

(Conditions for measuring the volume average particle size of hot rolling oil emulsion particles)

• Measuring instrument: Coulter Counter Multisizer (manufactured by Beckman Coulter, Inc.)
• Measuring temperature: 25 ° C
• Dilution Conditions: 30 μl was taken from each of the produced hot rolling oils and diluted to 100 ml with a dilution solution for blood (manufactured by Wako Pure Chemical Industries, Ltd.) when the volume average particle size was measured.

The hot rolling oils were subjected to the test examples described below in which lubricity was evaluated in rolling an aluminum alloy sheet, surface quality of the sheet, iron corrosion protection and gripping performance.

<Test Example 1>

Using each of the produced hot rolling oils, a single-pass strip rolling process (200 mmφ × 200 mm width, SUJ-2, Hs = 60) was carried out under the following conditions. The hot rolling oil emulsion was fed into the hot rolling process by spraying on the roller cooling roll.

(Rolling conditions)

• Material to be rolled: Aluminum alloy material (A5182, 40 mm wide × 700 mm long × 3.3 mm thick)
• Roll roughness: Polishing was carried out in the rolling direction with abrasive paper so that the roughness in the sheet width direction could be set to Ra = 0.3-0.4 μm (Rz = 3.5-4.0 μm).
• Sheet temperature: 510 ° C
• Rolling speed: 40 m / min
• Roll reduction: 45% (average for four pieces)
• Pre-rolling: A pure aluminum material (A1100, 40 mm wide × 700 mm long × 3.5 mm thick) was previously rolled at a rolling reduction of 70%.

(Conditions for the supply of hot rolling oil emulsion)

• Spray rate: 2 L / minute × one for each of the upper and lower parts, 200 kPa

<Rolling smoothness (rolling test)>

The rolling load at a rolling reduction of 45% was used to evaluate rolling smoothness. The test was conducted four times using each hot rolling oil, and the average was used as an index for rolling lubricity. When the rolling load is 430 MPa or less, the rolling lubricity is good. The results are shown in Table 1. The rolling load indicates the surface pressure, which is: the average of the loads measured with a load cell in the twin-rolling mill during rolling; and the contact area calculated from the sheet thicknesses before and after rolling is calculated.

<Gripping performance (rolling test)>

The coefficient of friction during pre-rolling was used to evaluate the "gripping performance" of a pure aluminum sheet. The test was performed four times using each hot rolling oil and the mean was used as an index of gripping performance. When the friction coefficient is 0.16 or more, the gripping performance is good. The results are shown in Table 1.

The coefficient of friction was determined by a method of performing a rolling process using a work roll having projecting marks, measuring the transferred marking gap (the distance between the marks) on the rolled material (the surface of the rolled sheet), calculating a forward slip from the distance Li between specific protruding marks on the rolling mill roll and calculating the friction coefficient from the following formulas. μ = 0.5 × [(h1-h2) / R2] ^0.5 / {1 - 2 × [(1-r) × δ / r] ^0.5 }, where μ represents the coefficient of friction, h1 the sheet thickness (mm) before rolling, h2 the sheet thickness (mm) after rolling, R2 the smoothed roll diameter (mm), r the rolling reduction and δ the forward slip. R2 = R × {1 + 16 × (1-v ² ) × P / [π × E × b × (h1-h ² )]}, where R represents the roll diameter, v the Poisson's constant, P the rolling load, E the Young's modulus and b the sheet width. r = (h1-h2) / h1 δ = (L1-L2) / L1, where L1 represents the distance (mm) between the protrusions (marks) on the roller cooling roll and L2 represents the distance (mm) between the marks transferred to the rolled sheet.

According to one embodiment of the invention, the test was carried out using the following specific values: h1 = 3.5 mm, r = 0.7, R = 100 mm, b = 40 mm.

Since the roller is made of iron, v and E are 0.3 and 20,000, respectively, which are values specific to iron.

<Test Example 2: Surface quality of sheet (alumite test)>

The rolled sheet obtained in Test Example 1 was subjected to alumite treatment under the conditions shown below, and the surface of the rolled sheet after the alumite treatment was measured for whiteness, when the surface quality of the sheet was evaluated. The test was conducted four times using each hot rolling oil, and the average was used as an index for the surface quality of the sheet. When the below-mentioned whiteness degree is judged to be 4 or more, the surface quality of the sheet is good. The results are shown in Table 1.

(Test Conditions)

• Treatment Solution: An aqueous 15% (w / v) sulfuric acid solution
• Treatment temperature: 20 ° C
• Current density: 2 A / dm ²
• Duration of treatment: 20 minutes
• Purification Procedure: Immersion in tap water flowing at 2 L / minute for 10 minutes was followed by washing with demineralized water.

(Measurement Conditions)

• Measuring equipment: spectroscopic colorimeter SE-2000 (manufactured by NIPPON DENSHOKU INDUSTRIES CO., LTD.)
• Measurement item: Whiteness WB

Evaluation procedure (in the case of A5182)

The evaluation was carried out according to the following criteria. The higher the degree of whiteness WB, the better the surface quality of the sheet.
5: The whiteness degree WB is 34 or more.
4: The whiteness degree WB is 30 to less than 34.
3: The whiteness degree WB is 24 to less than 30.
2: The whiteness degree WB is 20 to less than 24.
1: The degree of whiteness WB is less than 20.

<Test Example 3 (Iron corrosion protection)>

Each produced hot rolling oil was subjected to a corrosion test under the following conditions, and the corrosion rate (mg / ^m2 · day) was used to evaluate the iron corrosion protection. The test was conducted four times using each hot rolling oil, and the average was used as an index for iron corrosion protection. When the corrosion rate is 200 mg / m ² · day or less, the iron corrosion protection is good. The results are shown in Table 1. The corrosion rate was determined by a method including measuring the mass of the test piece with a precision balance before and after the test, and calculating the corrosion rate from the reduction in the mass and area of the test piece.

(Test Conditions)

• Test piece: SS-400 sheet (3 mm thick × 50 mm × 50 mm)
• Pretreatment: The test piece was polished with # 240 polishing paper and then degreased with a solvent.
• Immersion Process: The test piece was completely immersed in each hot rolling oil while stirring with an M-type homomixer at 6,000 rpm.
• Test temperature: 60 ° C
• Test duration: 3 days.

In Table 1, the mineral oils, fatty acids, oils and fats, esters, extreme pressure agents, corrosion inhibitors, organic salts of copolymers and other additives have the meanings listed below.
Mineral Oil A: paraffinic mineral oil (having a kinematic viscosity of 30 mm ² / second at 40 ° C) (Super Oil K32, manufactured by Nippon Oil Corporation)
Mineral Oil B: Naphthene-based mineral oil (having a kinematic viscosity of 30 mm ² / second at 40 ° C) (Diana Fresia N-28, manufactured by Idemitsu Kosan Co., Ltd.)
Fatty acid A: oleic acid (LUNAC OP, manufactured by Kao Corporation)
Oil and fat A: palm oil (RPO ACE, manufactured by UEDA OILS AND FATS MFG CO., LTD.)
Oil and Fat B: Lard (reagent made by Kishida Chemical Co., Ltd.)
Ester A: butyl stearate (EXCEPARL BS, manufactured by Kao Corporation)
Ester B: dilauryl phthalate (VINYCIZER 124, manufactured by Kao Corporation)
Ester C: trimethylolpropane coconut oil fatty acid triester (ADDLUBE E-124, manufactured by Kao Corporation)
High pressure agent A: tricresyl phosphate (DURAD TCP, manufactured by AJINOMOTO CO., INC.)
High pressure agent B: triisooctyl phosphite (JP-308E, manufactured by Johoku Chemical Co., Ltd.)
Corrosion Inhibitor A: Polyoxyethylene laurylamine (5 times average EO addition, HLB = 10.4) (AMIET 105, manufactured by Kao Corporation)
Organic Acid Salt of Copolymer A: A product of neutralization of a copolymer of dimethylaminopropylacrylamide / acrylamide / sodium salt of acrylic acid (80/5/15) with acetic acid (having a weight average molecular weight of 100,000 synthesized in the laboratory at a reaction temperature of 50 ° C using a polymerization initiator and monomers manufactured by Wako Pure Chemical Industries, Ltd.)
Organic acid salt of copolymer B: A product of neutralization of a copolymer of dimethylaminopropylmethacrylamide / acrylamide / sodium salt of acrylic acid (84/1/15) with glycolic acid (having a weight average molecular weight of 50,000 synthesized in the laboratory at a reaction temperature of 50 ° C using a polymerization initiator and monomers manufactured by Wako Pure Chemical Industries, Ltd.)
Additive A: Rust inhibitor (hexadecenylsuccinate) (L-ASA, made by Kao Corporation)
Additive B: antioxidant (2,6-di-tert-butyl-p-cresol) (YOSHINOX BHT, manufactured by API Corporation)
Additive C: polyoxyethylene lauryl ether (average molar EO addition of 7 moles, HLB = 12.1) (EMULGEN 707, manufactured by Kao Corporation)
Additive D: triethanolamine (reagent manufactured by Wako Pure Chemical Industries, Ltd.)
Additive E: coconut oil reduced alcohol (KALCOL 2455, manufactured by Kao Corporation)

Table 1 shows that hot rolling oil emulsions prepared using lubricating oils for use in hot rolling oil of the invention have a satisfactory level of lubricity, surface quality of the sheet and iron corrosion protection when rolling aluminum alloy sheets and a satisfactory level of sheet gripping performance of pure aluminum and that comparative products which do not satisfy the features of the invention have a problem with at least one of the performances. Therefore, the lubricating oil for use in hot rolling oil of the invention is also effective for lubricity, surface quality of the sheet, and iron corrosion protection in rolling pure aluminum sheets and effective in gripping aluminum alloy sheets.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2869850 [0006]
• JP 2990021 [0006]

Cited non-patent literature

• "Keikinzoku no Kenkyu to Gijutsu no Ayumi" (History of Light Metals Research and Technology), published November 30, 1991 by The Japan Institute of Light Metals) [0035]

Claims (4)

A lubricating oil for use in hot rolling oil for aluminum sheet, comprising: (a) a mineral oil having a kinematic viscosity of 80 mm ² / second or less at 40 ° C; (b) 1 to 14% by mass of a fatty acid having 10 to 22 carbon atoms; (c) 5 to 15% by weight of an oil and fat and / or a synthetic ester; (d) 5 to 10% by weight of a high pressure phosphorus-containing agent; (e) 0.1 to 1% by weight of a polyoxyethylene alkylamine; and (f) 0.1 to 10% by mass of an organic acid salt of a copolymer composed of a (meth) acrylic acid salt, (meth) acrylamide and at least one amine monomer represented by formula (1): [Formula 1]

wherein R ^{1 represents} a hydrogen atom or a methyl group, R ² and R ³ denote the same or different alkyl radicals having 1 to 3 carbon atoms, A is -NH- and m is an integer of 1 to 3, wherein the organic acid salt of the copolymer Weight average molecular weight of 10,000 to 1,000,000, an organic acid used to form the organic acid salt of the copolymer represented by formula (2): R ⁴ COOH, wherein R ^{4 is} an alkyl group having 1 to 5 carbon atoms, a hydroxyalkyl group having 1 to 5 represents carbon atoms, a carboxyalkyl radical having one alkyl moiety of 1 to 5 carbon atoms or a carboxyl group, and the mass ratio of component (c) to component (d) (component (c) / component (d)) 1 / 0.6 to 1 / 1 amounts to. The lubricating oil for use in hot rolling oil for aluminum sheet according to claim 1, wherein the component (c) is butyl stearate. An aluminum sheet hot rolling oil comprising the lubricating oil for use in hot rolling oil according to claim 1 or 2 and water. A method for producing a hot rolled sheet, comprising a step of hot rolling an aluminum sheet in the presence of the aluminum sheet hot rolling oil according to claim 3.