JPH0598284A - Water-dispersible cold rolling oil for aluminum and its feeding - Google Patents

Abstract

PURPOSE:To obtain the title oil excelling in lubricating properties and not causing the formation of oil stains after rolling by adding a specified oleaginous material to a base oil comprising polypropylene, polyisobutylene or polybutene. CONSTITUTION:The title oil is prepared by adding 5-20wt.% at least one oleaginous material selected from among an alkoxyalkyl ester, a neopentyl glycol derivative, a glycerol derivative, a trimethylolpropane derivative, a higher alcohol derivative and a hydroxylated mono- or di-carboxylic ester to a base oil comprising least one member selected from among polypropylene, polyisobutylene and polybutene each of which has a molecular weight of 200-330. According to a method for feeding the above rolling oil, a used rolling oil emulsion can be subjected the oil/water separation at high efficiency and can be freed from a fine powder of abrasion by precision filtration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling oil for rolling aluminum and aluminum alloys (hereinafter simply referred to as "aluminum"), which is superior in lubricity to a non-aqueous rolling oil, and moreover, when the rolled sheet material is annealed. The present invention relates to a water-soluble cold rolling oil that does not generate oil stain and a method for supplying the same.

[0002]

2. Description of the Related Art Conventionally, non-aqueous rolling oil has been used for cold rolling of aluminum. This rolling oil is a refined mineral oil having a viscosity of 3 to 4 cst at 40 ° C. as a base oil, and lauryl alcohol as an oiliness agent mixed therein.

This is excellent in that a plate with good gloss can be obtained, but since the cooling capacity is lower than that of the water-based rolling oil, the temperature of the roll or plate is remarkably increased in the rolling under high speed and high pressure, and the plate It has drawbacks that shape control becomes difficult and there is a risk of fire.

Therefore, in order to solve the above-mentioned drawbacks, a water-soluble rolling oil and its use technology have been developed, and a lubricant containing mineral oil and an alkoxyalkyl ester in 90 to 98 wt% of water (JP-A-62-172095). ), HLB3-5 in 60-95wt% water
Lubricant containing mineral emulsifier, mineral oil, carboxylic acid, etc. (JP-A-60-248797), lubricant containing 85-90 wt% water containing mineral oil, fatty acid glycol ester, polyisobutylene, etc. (JP-A-50-67304). ) Etc. have been proposed.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention JP-A-62-172095
According to the invention, the main component of the lubricant composition is mineral oil, and for cold rolling, light mineral oil of 3 to 5 cst at 40 ° C. is desirable.

Certainly, aluminum is rolled with a lubricant using mineral oil having a viscosity of 5 cst or more at 40 ° C., and the rolled material is
When annealed at a temperature of 330 ° C or lower, the combustion residue of the lubricant remains on the surface of the material and causes oil stain.

Therefore, it is necessary to use a mineral oil having a viscosity of 5 cst or less at 40 ° C., but in that case, the lubricity is remarkably poor as compared with a non-aqueous lubricant using a mineral oil having the same viscosity, and the characteristic of being water-soluble is lost. Will end up.

That is, the lubricant of the invention of JP-A-62-172095 has a drawback in that the lubricity is remarkably poor as compared with a non-aqueous lubricant having the same viscosity level.

JP-A-60-248797 discloses that a lubricant containing a fatty acid having a C number of 12 to 18 and a sorbitan ester is used as a W / O or W / O / W emulsion for rolling lubrication of aluminum. Although fatty acids and sorbitan esters of several 12 to 18 have a water stain preventing effect, they are widely known to promote the generation of oil stains, and are therefore not suitable as aluminum rolling oil additives.

[0010] Further, in JP-A-50-67304, since substances having a large molecular weight are generally used, there is a concern that oil stain may be generated. Particularly, phosphate ester salts are used for rust prevention (water stain prevention). Has a large effect, but promotes the generation of oil stain, and is not suitable as an additive for aluminum cold rolling oil.

Polyisobutylene is used as a thickener, but it has a large molecular weight of 350 to 800, which may cause oil stain.

Therefore, an object of the present invention is to provide a water-dispersible cold rolling oil which is superior in lubricity to a non-aqueous rolling oil and does not cause oil stain when the rolled sheet material is annealed, and a supply method thereof. It is a thing.

[0013]

The gist of the present invention is to determine the molecular weight.
200-330 polypropylene, polyisobutylene and polybutene base oil 80-95 wt% consisting of at least one or more one or more of the following (a) ~ (f) one or more oily agent 5-20 wt% The first invention is a water-dispersible cold rolling oil for aluminum, and (a) an alkoxyalkyl ester represented by the general formula R ₂ COO (C _m H _2m O) _n R _{1 is used} , where m = an integer of 2 to 4 n = An integer of 1 to 3 R ₂ = an alkyl group having a C number of 9 to 21 R ₁ = an alkyl group having a C number of 1 to 6 (b) a neopentyl glycol derivative represented by the following general formula (b-1) a general formula ( _{CH 3) 2 C (CH 2} OCOR 3) CH 2 O
H (b-2) the formula _{(CH 3) 2 C [CH} 2 O (C m H 2m O) n C
OR ₄ ] ₂ where m = an integer of 2 to 4 n = 1 to an integer of ₃ R ₃ and R ₄ = alkyl group having a C number of 1 to 9 (c) Glycerin derivative represented by the following general formula Here, m = 2 to 4 integer n = 1 to 3 integer R ₅ , R ₆ , R ₇ , R ₈ , R ₉ = C number of 1 to 9 alkyl group (d) Tris represented by the following general formula. trimethylolpropane derivatives (d-1) the formula _{C 2 H 5 C (CH 2} OCOR 10) 2 CH 2 O
H (d-2) the general formula _{C 2 H 5 C [CH 2} O (C m H 2m O) n CO
R ₁₁ ] ₃ where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₀ and R ₁₁ = an alkyl group having a C number of 1 to 9 (e) a higher alcohol derivative represented by the following general formula R ₁₂ O (C _m H _2m O) _n H where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₂ = alkyl group having a C number of 10 to 22 (f) Oxymono represented by the following general formula or Dicarboxylic acid ester (f-1) Lactic acid ester represented by the general formula CH ₃ CH (OH) COOR ₁₃ (f-2) Salicylic acid ester represented by the general formula C ₆ H ₄ (OH) COOR ₁₄ (f-3 ) A gallic acid ester represented by the general formula C ₆ H ₂ (OH) ₃ COOR ₁₅ (f-4) A malic acid ester represented by the general formula C ₂ H ₃ (OH) (COOR ₁₆ ) ₂ (f-5 ) general formula _{C 2 H 2 (OH) 2} (COOR 17) R 13 tartrates here represented by _{2, R 14, R 15,} R 16, R 17 = C number 1-18 alkyl group, and The second invention is a cold rolling oil for aluminum in which the rolling oil is an aqueous emulsion having a concentration of 5 to 20%, and the rolling oil is press-fitted into water immediately before the rolling roll is introduced, and the concentration is 3 to 20%. The mixture of the rolling oil and water that has been subjected to the process of supplying the mixture to the rolling roll from the nozzle through a static mixer and the rolling lubrication, if necessary, is separated into oil and water by a centrifugal separator or a fiber membrane separator. A third invention is a method for supplying a cold rolling oil for aluminum, which comprises a step and a step of separately filtering the oil and the separated rolling oil and water and reusing them.

Next, each constituent material used in the first and second inventions of the present invention will be described.

Polypropylene, Polyisobutylene and Polybutene Aluminum As base oils for cold rolling oils, these substances preferably have a molecular weight of 200 to 330. Substances with a molecular weight of less than 200 have too low a viscosity and lack lubricity. Molecular weight 3
It cannot be used with substances exceeding 30 because oil stain is generated.

It is preferable that these oligomers are not hydrogenated, but they may be hydrogenated.

Alkoxyalkyl Esters (a) Esters of this type function as excellent oiliness agents and have weak self-emulsifying properties and are therefore suitable as additives for water-dispersible cold rolling oils.

If the addition amount is less than 5 wt%, the lubricity is insufficient,
If it exceeds 20 wt%, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the ester represented by the formula (a) include 2-methoxyethyl caprate, 2-butoxyethyl caprate, 2-hexyloxyethyl caprate, 2-methoxyethyl palmitate, 2-butoxyethyl palmitate. , 2-hexyloxyethyl palmitate,
2-Methoxyethyl behenate, 2-butoxyethyl behenate, 2-hexyloxyethyl behenate, 2- (2-methoxyethoxy) ethyl caprate, 2-caprate
(2 butoxyethoxy) ethyl, 2- (2 hexyloxyethoxy) ethyl caprate, 2- (2 palmitate
Methoxyethoxy) ethyl, 2- (2butoxyethoxy) ethyl palmitate, 2- (2hexyloxyethoxy) ethyl palmitate, 2- (2methoxyethoxy) ethyl behenate, 2- (2butoxyethoxy) behenate
Ethyl, 2- (2 hexyloxyethoxy) ethyl behenate and the like can be mentioned.

The hydrocarbon groups of the acid and alcohol of these esters may be straight chain hydrocarbons or side chain hydrocarbons.

In the above general formula, the C numbers of R ₁ and R ₂ are
If it is smaller than the above lower limit, the lubricity deteriorates,
When it exceeds the upper limit, oil stain occurs. If both m and n are larger than the upper limits, oil stain occurs.

Neopentyl glycol derivative (b) These compounds represented by the general formulas (b-1) and (b-2) function as excellent oiliness agents. In particular, the compound represented by the general formula (b-2) also has a self-emulsifying property and is therefore suitable as an additive for a water-dispersible cold rolling oil.

If the addition amount is less than 5 wt%, the lubricity is insufficient,
If it exceeds 20% by weight, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the ester represented by the general formula (b-1) or (b-2) include neopentyl glycol monoacetic acid ester, neopentyl glycol monocaproic acid ester,
Neopentyl glycol monocapric acid ester, neopentyl glycol ethylene oxide 2 mol adduct diacetate, neopentyl glycol ethylene oxide 2 mol adduct dicaproic acid ester, neopentyl glycol ethylene oxide 2 mol adduct Dicapric acid ester, neopentyl glycol ethylene oxide 4 mol adduct diacetic acid ester, neopentyl glyco-
Diethylene glycol 4 mol adduct dicaproic acid ester, neopentylglycol ethylene oxide 4 mol adduct dicapric acid ester and the like can be mentioned.

The hydrocarbon group of the acid of these esters may be a straight chain hydrocarbon or a hydrocarbon having a side chain.

When the C numbers of R ₃ and R ₄ are larger than the upper limits, oil stain occurs. If both m and n are larger than the upper limits, oil stain occurs.

Glycerin Derivative (c) These compounds represented by the general formulas (c-1) and (c-2) function as excellent oiliness agents. In particular, the compound represented by the general formula (c-2) also has a self-emulsifying property and is therefore suitable as an additive for a water-dispersible cold rolling oil.

If the addition amount is less than 5 wt%, the lubricity is insufficient,
If it exceeds 20 wt%, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the ester represented by the general formulas (c-1) and (c-2) include glycerin diacetate ester, glycerin dicaproate ester, glycerin dicaprate ester, glycerin ethylene oxide 3 mol adduct triacetate. Ester, glycerin ethylene oxide 3 mol adduct tricaproic acid ester, glycerine ethylene oxide 3 mol adduct tricapric acid ester, glycerine ethylene oxide 6 mol adduct triacetic acid ester, glycerin ethylene oxide 6 mol adduct tricaproic acid ester, glycerin ethylene oxide 6 A molar adduct tricapric acid ester, etc. are mentioned.

The acid hydrocarbon group of these esters may be either a straight chain hydrocarbon or a side chain hydrocarbon.

When the C number of R _{5 to} R ₉ is larger than the upper limit, oil stain occurs. If both m and n are larger than the upper limits, oil stain occurs.

Trimethylolpropane Derivative (d) These compounds represented by the general formulas (d-1) and (d-2) function as excellent oiliness agents. In particular, the compound represented by the general formula (d-2) also has a self-emulsifying property and is therefore suitable as an additive for a water-dispersible cold rolling oil.

If the addition amount is less than 5 wt%, the lubricity is insufficient,
If it exceeds 20 wt%, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the ester represented by the general formulas (d-1) and (d-2) include trimethylolpropane diacetic acid ester, trimethylolpropane dicaproic acid ester, trimethylolpropane dicapric acid ester and trimethylol- Rupropane ethylene oxide 3 mol adduct triacetate, trimethylol Propane ethylene oxide 3 mol adduct tricaproate, trimethylol
L-propane ethylene oxide 3 mol adduct tricapric acid ester, trimethylol propane ethylene oxide 6 mol adduct triacetate ester, trimethylol propane ethylene oxide 6 mol adduct tricaproic acid ester, trimethylol propane ethylene oxide 6 mol adduct Tricapric acid ester, etc. are mentioned.

The hydrocarbon group of the acid of these esters may be either a straight chain hydrocarbon or a side chain hydrocarbon.

When the C number of R ₁₀ and R ₁₁ is larger than the upper limit, oil stain occurs. If both m and n are larger than the upper limits, oil stain occurs.

Higher alcohol derivative (e) Since these compounds represented by the general formula (e) function as an excellent oiliness agent and also have self-emulsifying property, they are suitable as an additive for a water-dispersible cold rolling oil. Is.

If the addition amount is less than 5 wt%, the lubricity is insufficient,
If it exceeds 20 wt%, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the compound represented by the general formula (e) include ethylene glycol mono-n-decyl ether, ethylene glycol mono-n-cetyl ether, ethylene glycol mono-n-behenyl ether, and diethylene glycol. -N-decyl ether, diethylene glycol-n-cetyl ether, diethylene glycol-n-behenyl ether, and the like.

The hydrocarbon groups of these alcohols may be straight chain hydrocarbons or side chain hydrocarbons.

If the C number of R ₁₂ is smaller than the lower limit, lubricity is insufficient, and if it is larger than the upper limit, oil stain occurs. If both m and n are larger than the upper limits, oil stain occurs.

Oxymono or dicarboxylic acid ester (f) These compounds represented by the general formulas (f-1) to (f-5) function as an excellent oiliness agent. If the addition amount is less than 5 wt%, the lubricity is insufficient, and if it exceeds 20 wt%, oil stain is generated when the rolled sheet is annealed, which is not preferable.

Examples of the esters represented by the general formulas (f-1) to (f-5) include dimethyl malate, ditridecyl malate, distearyl malate and the like.

The hydrocarbon groups of the alcohols of these esters may be straight chain hydrocarbons or side chain hydrocarbons.

When the C number of R _{13 to} R ₁₇ is larger than the upper limit, oil stain occurs.

Antioxidant, Antiseptic, Antirust Agent In the rolling oil of the present invention, a small amount of antioxidant, antiseptic agent, antirust agent, etc. may be added, if necessary.

Next, each step of the second invention will be described.

The rolling oil supply method of the present invention is carried out by the apparatus schematically shown in FIG.

Formation of Emulsion (Mixing of Water and Oil) Generally, an emulsion is formed by stirring water and oil in a tank, but the rolling oil of the present invention does not use an emulsifier actively. , An emulsion cannot be formed by such a method.

A method devised therefor is a method of forming an emulsion by using a mixer as shown in FIG. 1 to press oil into water being pumped.

In this case, the pressure of the pumped water is ² Kgf / cm ²
As described above, the pressure of the oil to be injected can be obtained by increasing the pressure of water by ² Kgf / cm ² or more.

When the water-dispersible cold rolling oil for aluminum according to claim 1 is made into a 3 to 20% emulsion by such a method, the emulsion average particle size is 3 to 30 μm.
m was an emulsified state suitable for rolling lubrication.

When it is desired to form an emulsion having a slightly small particle size, it is effective to insert a static mixer after mixing water and oil.

Oil-Water Separation Step It is preferable to use a mixture of diatomaceous earth and activated clay as a filtration aid in order to remove fine abrasion powder in an oil filtration equipment described later, for which the water content in the oil is used. 200ppm
The following oil-water separation step is required.

As a means for oil / water separation, a centrifuge or a fiber membrane separator is preferable because it is efficient and the water content in the oil after oil / water separation is 200 ppm or less.

Any centrifugal separator may be used as long as it can obtain a centrifugal effect of 100 to 4000 G.

Further, the fiber membrane separator has a fiber pore size of 1 to 50 μm.
It is preferable to use m. Filtration process Since the separated oil contains fine abrasion powder, precision filtration is performed using diatomaceous earth and activated clay as a filtration aid.

Since the separated water contains a small amount of oil and a relatively large metal powder, filtration with diatomaceous earth as a filtration aid or filtration with a paper filter may be performed.

[0059]

【Example】

Example 1 JIS 50 having a plate thickness of 1.2 mm, a width of 70 mm and a length of 450 mm as a material to be rolled
A rolling load was measured when a 52 aluminum alloy sheet material was rolled by a rolling machine having a roll diameter of 155 mm at a rolling speed of 35 m / min and a rolling reduction of 60%.

The emulsion subjected to rolling lubrication has a water pressure of 3 Kgf.
/ cm ² , hydraulic pressure 8 Kgf / cm ² , and total flow rate 4 l / mim.

The used emulsion was separated into oil and water by a centrifuge (centrifugal effect 1000 G), but the separation was instantaneous and the water content in the separated oil was 200 ppm.

Next, the separated oil was filtered using a mixture of diatomaceous earth and activated clay as a filter aid to remove abrasion powder (Al powder) generated during rolling and then reused.

The invention examples Nos. 1 to 61 all had a rolling load of 20.
It was less than Ton-f, and no oil stain was observed during annealing.

However, Comparative Examples No. 62, 64, 66, 68, 8
1,85,87 have low molecular weight of oligomer, small C number of acid or alcohol, small amount of ester addition, or low emulsion concentration, resulting in insufficient lubricity and rolling load of 23 It became as big as ~ 25 Ton-f.

Comparative Examples No. 63, 65, 67, 69 to 80, 82 to 8
4,86,88 have good lubricity, but have high molecular weight of oligomer, C of ester acid or alcohol.
The occurrence of oil stain was observed because of the large number, the large number of moles of alkylene oxide added, the large amount of ester added, or the high emulsion concentration.

[0066]

[Table 1]

[0067]

[Table 2]

[0068]

[Table 3]

[0069]

[Table 4]

Example 2 An oil-water separation and filtration experiment was carried out on a No. 5 rolling oil-containing emulsion that was rolled under the conditions shown in Example 1.

Oil-water separation was carried out using a centrifuge and a fiber membrane separator, and filtration was carried out using diatomaceous earth + activated clay as a filter aid.

Table 2 As shown in Invention Examples No. 1 to 10, centrifugal force
It was shown that 100% oil-water separation was possible in a short time for both 100-4000 G centrifugation and fiber membrane separation with a pore size of 1-50 μm, and the water content in the oil after separation was 200 ppm or less.

The separated oil contained 100 to 120 ppm of abrasion powder, but could be reduced to 10 ppm or less by filtration.

[0074]

[Table 5]

[0075]

As described above, the rolling oil of the present invention is superior in lubricity to the non-aqueous rolling oil, and therefore can be rolled at high speed under high pressure and does not cause oil stain on the material to be rolled. Is. Further, the oil supply method of the present invention using this rolling oil can separate the used rolling oil emulsion with high efficiency oil and water, and can also finely filter fine abrasion powder.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a mixer for forming an emulsion by mixing rolling oil and water used in the present invention.

FIG. 2 is an explanatory view of a rolling oil supply device for carrying out the rolling oil supply method of the present invention.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location C10M 129: 16 129: 74 129: 76) C10N 20:04 30:00 A 8217-4H Z 8217-4H 30: 06 40:24 A 8217-4H 70:00 (72) Inventor Hideo Ito 5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industry Co., Ltd. (72) Inventor Masami Sumitomo Nukata, Yamatokoriyama City, Nara Prefecture 1021 Kitabemachi Daito Kagaku Kogyo Co., Ltd., Nara Production Technology Office, Technical Research Laboratory (72) Inventor Kazuo Yamaguchi 1021 Sumatabe Kitamachi, Yamato-gun, Nara Daiba Kagaku Kogyo Co., Ltd.

Claims (3)

[Claims] 1. To 80 to 95 wt% of a base oil comprising at least one of polypropylene having a molecular weight of 200 to 330, polyisobutylene and polybutene is added 5 to 20 wt% of one or more of the oiliness agents shown in (a) to (f) below. A water-dispersible cold rolling oil for aluminum, characterized in that (a) Alkoxyalkyl ester represented by the general formula R ₂ COO (C _m H _2m O) _n R ₁ where m = 2 to 4 integer n = 1 to 3 integer R ₂ = C number 9 to 21 Alkyl group R ₁ = alkyl group having 1 to 6 C numbers (b) Neopentyl glycol derivative represented by the following general formula (b-1) General formula (CH ₃ ) ₂ C (CH ₂ OCOR ₃ ) CH ₂ O
H (b-2) the formula _{(CH 3) 2 C [CH} 2 O (C m H 2m O) n C
OR ₄ ] ₂ where m = an integer of 2 to 4 n = 1 to an integer of ₃ R ₃ and R ₄ = alkyl group having a C number of 1 to 9 (c) Glycerin derivative represented by the following general formula Here, m = 2 to 4 integer n = 1 to 3 integer R ₅ , R ₆ , R ₇ , R ₈ , R ₉ = C number of 1 to 9 alkyl group (d) Tris represented by the following general formula. trimethylolpropane derivatives (d-1) the formula _{C 2 H 5 C (CH 2} OCOR 10) 2 CH 2 O
H (d-2) the general formula _{C 2 H 5 C [CH 2} O (C m H 2m O) n CO
R ₁₁ ] ₃ where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₀ and R ₁₁ = an alkyl group having a C number of 1 to 9 (e) a higher alcohol derivative represented by the following general formula R ₁₂ O (C _m H _2m O) _n H where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₂ = alkyl group having a C number of 10 to 22 (f) Oxymono represented by the following general formula or Dicarboxylic acid ester (f-1) Lactic acid ester represented by the general formula CH ₃ CH (OH) COOR ₁₃ (f-2) Salicylic acid ester represented by the general formula C ₆ H ₄ (OH) COOR ₁₄ (f-3 ) A gallic acid ester represented by the general formula C ₆ H ₂ (OH) ₃ COOR ₁₅ (f-4) A malic acid ester represented by the general formula C ₂ H ₃ (OH) (COOR ₁₆ ) ₂ (f-5 ) general formula _{C 2 H 2 (OH) 2} (COOR 17) R 13 tartrates here represented by _{2, R 14, R 15,} R 16, the alkyl group of R ₁₇ = C number from 1 to 18 2. One or more 5 to 20 wt% of an oiliness agent shown in the following (a) to (f) is added to 80 to 95 wt% of a base oil consisting of at least one or more of polypropylene having a molecular weight of 200 to 330, polyisobutylene and polybutene. A cold rolling oil for aluminum and aluminum alloys, characterized in that the resulting rolling oil is an aqueous emulsion having a concentration of 5 to 20%. (a) Alkoxyalkyl ester represented by the general formula R ₂ COO (C _m H _2m O) _n R ₁ where m = 2 to 4 integer n = 1 to 3 integer R ₂ = C number 9 to 21 Alkyl group R ₁ = alkyl group having 1 to 6 C numbers (b) Neopentyl glycol derivative represented by the following general formula (b-1) General formula (CH ₃ ) ₂ C (CH ₂ OCOR ₃ ) CH ₂ O
H (b-2) the formula _{(CH 3) 2 C [CH} 2 O (C m H 2m O) n C
OR ₄ ] ₂ where m = an integer of 2 to 4 n = 1 to an integer of ₃ R ₃ and R ₄ = alkyl group having a C number of 1 to 9 (c) Glycerin derivative represented by the following general formula Here, m = 2 to 4 integer n = 1 to 3 integer R ₅ , R ₆ , R ₇ , R ₈ , R ₉ = C number of 1 to 9 alkyl group (d) Tris represented by the following general formula. trimethylolpropane derivatives (d-1) the formula _{C 2 H 5 C (CH 2} OCOR 10) 2 CH 2 O
H (d-2) the general formula _{C 2 H 5 C [CH 2} O (C m H 2m O) n CO
R ₁₁ ] ₃ where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₀ and R ₁₁ = an alkyl group having a C number of 1 to 9 (e) a higher alcohol derivative represented by the following general formula R ₁₂ O (C _m H _2m O) _n H where m = an integer of 2 to 4 n = 1 to an integer of 3 R ₁₂ = alkyl group having a C number of 10 to 22 (f) Oxymono represented by the following general formula or Dicarboxylic acid ester (f-1) Lactic acid ester represented by the general formula CH ₃ CH (OH) COOR ₁₃ (f-2) Salicylic acid ester represented by the general formula C ₆ H ₄ (OH) COOR ₁₄ (f-3 ) A gallic acid ester represented by the general formula C ₆ H ₂ (OH) ₃ COOR ₁₅ (f-4) A malic acid ester represented by the general formula C ₂ H ₃ (OH) (COOR ₁₆ ) ₂ (f-5 ) general formula _{C 2 H 2 (OH) 2} (COOR 17) R 13 tartrates here represented by _{2, R 14, R 15,} R 16, the alkyl group of R ₁₇ = C number from 1 to 18 3. The water-dispersible cold-rolling oil for aluminum according to claim 1 is press-fitted into water immediately before the rolling roll is introduced, and the concentration is reduced.
From the centrifugal separator or the fiber membrane separator, the mixture of rolling oil and water, which is mixed to 3 to 20%, and if necessary, is supplied to the rolling roll from the nozzle through a static mixer and rolling lubrication A method of supplying cold-rolling oil for aluminum, comprising the steps of separating the oil and water, and filtering the oil and the separated rolling oil and water separately and reusing them.