JP2843506B2 - Mold lubricating oil for continuous casting of aluminum and continuous casting method of aluminum using the lubricating oil - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold lubricating oil for continuous casting of aluminum (including an aluminum alloy, the same applies hereinafter) and a method of continuously casting aluminum using the lubricating oil.

[0002]

2. Description of the Related Art Conventionally, in continuous casting of aluminum, castor oil has been used as a mold lubricating oil. Castor oil has excellent lubricity when the molten aluminum is fed into contact with the mold, but mixes with the cooling water to form a stable emulsion. Emulsions containing castor oil have a high BOD (biochemical oxygen demand) load, and to remove castor oil from this emulsion,
It requires large-scale processing equipment for performing coagulation flotation processing, biological processing, and the like. For this reason, development of a lubricating oil having good lubricity and excellent oil-water separation properties has been demanded.

[0003]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in a lubricating oil for continuous casting of aluminum, and has an excellent lubricating property between a molten aluminum and a mold. Is difficult to be emulsified in a state of being mixed with water, and even after emulsification, the oil-water separation property is excellent, so that the load of the BOD in the cooling water can be easily reduced, and the lubricating oil for continuous casting An object of the present invention is to provide an aluminum continuous casting method using the same.

[0004]

According to the present invention, there is provided a mold lubricating oil for continuous casting of aluminum according to the present invention, which comprises a high-viscosity mineral oil having a kinematic viscosity of 300 to 2000 cSt at a temperature of 40.degree. The following (a),
Esters of the polyols shown in (b) and (c),
It is a feature of the present invention that 10 to 40% of at least one oily agent selected from the polyacrylic acid ester shown in (d) and the polymethacrylic acid ester shown in (e) is added. (A) Monoesters or diesters of neopentyl glycol represented by the following general formula (Chemical Formula 6) (wherein the C number of the esterified fatty acid is 10 to 20).

[0005]

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(B) A monoester, diester or triester of trimethylolpropane represented by the following general formula (Chemical Formula 7) (wherein the C number of the esterified fatty acid is 10 to 20).

[0007]

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(C) Monoesters, diesters, triesters or tetraesters of pentaerythritol represented by the following general formula (Chemical Formula 8), wherein the C number of the fatty acid to be esterified is 10-20.

[0009]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 9), wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt. ester.

[0011]

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(E) Polymethacrylic acid represented by the following general formula (Chemical Formula 10), wherein the C number of the alcohol to be esterified is 1 to 3, and the kinematic viscosity at 40 ° C. is 20,000 to 100,000 cSt. ester.

[0013]

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The continuous casting method of aluminum according to the present invention is characterized in that aluminum or aluminum alloy is continuously cast by continuously supplying the lubricating oil between the molten aluminum and the mold wall surface.

The significance and the reasons for the addition of the base oil and the various oily agents in the mold lubricating oil for continuous casting of aluminum according to the present invention will be described. Is higher and easier to separate from the cooling water,
The separation can be performed by a simple processing device, and the BOD load can be reduced.

In continuous casting of aluminum, it is necessary to form a uniform and sufficient lubricating oil film on the inner surface of the mold in order to maintain excellent lubricity at a high temperature portion between the surface of the molten aluminum and the inner wall surface of the mold. Therefore, as the mineral oil, it is preferable to use a high-viscosity mineral oil having a kinematic viscosity of 300 to 2000 cSt (centistokes) at a temperature of 40 ° C., and it is more preferable to use a mineral oil having a kinematic viscosity of 400 to 700 cSt. . If it is less than 300 cSt, it is difficult to obtain sufficient lubricity, and if the kinematic viscosity exceeds 2,000 cSt, it becomes difficult to supply the lubricating oil to the mold.

The preferred content of mineral oil is 60 to 90% by weight.
If it is less than 60%, the mold lubricity is low and the oil-water separation property is poor. When the content of the mineral oil is more than 90%, the oil-water separation property is good, but the viscosity of the lubricating oil is high, so that it is difficult to supply the lubricating oil to the mold.

Mineral oils serving as base oils include esters of polyols (polyhydric alcohols), preferably monoesters or diesters of neopentyl glycol (dihydric alcohol), monoesters and diesters of trimethylolpropane (trihydric alcohol). Alternatively, at least one selected from triesters, pentaerythritol (tetrahydric alcohol) monoesters, diesters, triesters or tetraesters, polyacrylic acid esters, and polymethacrylic acid esters is added as an oil agent. .

The ester of polyol is a compound having excellent heat stability and oxidation stability. When added to mineral oil,
Improves lubricity at high temperatures. Generally, the larger the valence of the polyol and the larger the number of the esters, the more excellent the lubricity, and the above-mentioned polyol ester is preferably used. Further, the greater the C number of the fatty acid to be esterified, the better the lubricity. However, in consideration of ease of handling, it is preferable to use a fatty acid having a C number of 10 to 20,
It is more preferable to use a compound having a C number of 14 or more from the viewpoint of lubricity and a C number of 18 or less from the viewpoint of compatibility with mineral oil.

It is desirable that all the OH groups of the polyol are esterified from the viewpoint of oil-water separation. Therefore, among the polyol esters, it is desirable to use diester for neopentyl glycol (dihydric alcohol), tryester for trimethylolpropane (trihydric alcohol), and tetraester for pentaerythritol (tetrahydric alcohol).

Esters of polyacrylic acid coexist with mineral oil to improve lubricating performance at high temperatures. Also, by increasing the molecular weight, the viscosity of the lubricating oil can be increased. In consideration of handleability and the like, an alcohol to be esterified having a C number of 1 to 3 and a kinematic viscosity of 20,000 to 100,000 cSt at 40 ° C. in consideration of compatibility with mineral oil is preferably used.

The ester of polymethacrylic acid, like the ester of polyacrylic acid, has lubricity at high temperatures and can increase the viscosity of lubricating oil by increasing the molecular weight. From the viewpoint of flexibility, the C number of the alcohol to be esterified with methacrylic acid is 1 to 3, and the kinematic viscosity at 40 ° C is 20000 to 1000 in consideration of compatibility with mineral oil.
Those of 00 cSt are preferably used.

The amount of the oil agent selected from the esters of polyols, esters of polyacrylic acid and esters of polymethacrylic acid is preferably in the range of 10 to 40% with respect to the mineral oil, and when it is less than 10%, the boundary lubricity is low. Insufficiently reduces mold lubricity, and if added over 40%,
The content of the mineral oil is reduced, and the mold lubricity is reduced and the oil-water separation property is also deteriorated.

The most preferred embodiments of the mold lubricating oil for continuous casting according to the present invention are as follows. 1.4
At a temperature of 0 ° C., 60-90% of a high-viscosity mineral oil having a kinematic viscosity of 300-2000 cSt,
And 10 to 40% of at least one oily agent selected from the esters of polyols shown in (c), the esters of polyacrylic acid shown in (d), and the esters of polymethacrylic acid shown in (e). This is a feature of the present invention. (A) Neopentyl glycol monoesters or diesters represented by the following general formula (Formula 11) (wherein the C number of the esterified fatty acid is 14 to 18).

[0025]

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(B) Monoesters, diesters or triesters of trimethylolpropane represented by the following general formula (Chemical Formula 12) (wherein the C number of the esterified fatty acid is 14 to 18).

[0027]

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(C) Monoesters, diesters, triesters or tetraesters of pentaerythritol represented by the following general formula (Chemical Formula 13) (wherein the C number of the esterified fatty acid is 14 to 18).

[0029]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 14) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0031]

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(E) Polymethacrylic acid represented by the following general formula (Chemical Formula 15) (where the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0033]

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2. 300 to 200 at a temperature of 40 ° C.
To 60-90% of a high viscosity mineral oil having a kinematic viscosity of 0 cSt,
At least one oily agent selected from the esters of polyols shown in the following (a), (b) and (c), the esters of polyacrylic acid shown in (d), and the esters of polymethacrylic acid shown in (e): A feature of the present invention is that 10 to 40% is added. (A) A diester of neopentyl glycol represented by the following general formula (Formula 16) (wherein the C number of the esterified fatty acid is 10 to 20).

[0035]

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(B) Triesters of trimethylolpropane represented by the following general formula (Formula 17) (wherein the number of C of the esterified fatty acid is 10 to 20).

[0037]

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(C) A tetraester of pentaerythritol represented by the following general formula (Chemical Formula 18) (wherein the C number of the esterified fatty acid is 10 to 20).

[0039]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 19) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0041]

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(E) Polymethacrylic acid represented by the following general formula (Chemical Formula 20), wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt. ester.

[0043]

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3. 300 to 200 at a temperature of 40 ° C.
To 60-90% of a high viscosity mineral oil having a kinematic viscosity of 0 cSt,
At least one oily agent selected from the following esters of polyols (a), (b) and (c), polyacrylates of (d) and polymethacrylic esters of (e) A feature of the present invention is that it is added by up to 40%. (A) A diester of neopentyl glycol represented by the following general formula (Formula 21) (wherein the C number of the esterified fatty acid is 14 to 18).

[0045]

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(B) Triesters of trimethylolpropane represented by the following general formula (Formula 22) (wherein the C number of the esterified fatty acid is 14 to 18).

[0047]

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(C) A tetraester of pentaerythritol represented by the following general formula (Formula 23), wherein the C number of the esterified fatty acid is 14 to 18.

[0049]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 24) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0051]

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(E) Polymethacrylic acid represented by the following general formula (Chemical Formula 25), wherein the C number of the esterified alcohol is 1 to 3 and the kinematic viscosity at 40 ° C. is 20,000 to 100,000 cSt. ester.

[0053]

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4. 400 to 700 at a temperature of 40 ° C.
60-90% of a high-viscosity mineral oil having a kinematic viscosity of cSt is added to a polyol ester shown in the following (a), (b) and (c), a polyacrylic acid ester shown in (d) and a polyester shown in (e). The invention is characterized in that at least one oil agent selected from esters of methacrylic acid is added in an amount of 10 to 40%. (A) Neopentyl glycol monoesters or diesters represented by the following general formula (Chemical Formula 26) (wherein the C number of the esterified fatty acid is 10 to 20).

[0055]

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(B) Monoesters, diesters or triesters of trimethylolpropane represented by the following general formula (Chemical Formula 27), wherein the fatty acid to be esterified has a C number of 10 to 20.

[0057]

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(C) Monoesters, diesters, triesters or tetraesters of pentaerythritol represented by the following general formula (Chemical Formula 28) (wherein the C number of the esterified fatty acid is 10 to 20).

[0059]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 29) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0061]

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(E) Polymethacrylic acid represented by the following general formula (Chemical Formula 30) (where the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0063]

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5. 400 to 700 at a temperature of 40 ° C.
60 to 90% of a high viscosity mineral oil having a kinematic viscosity of cSt is added to a polyol ester shown in the following (a), (b) and (c), an acid ester of a polyacryl shown in (d) and a polyester shown in (e). The invention is characterized in that at least one oil agent selected from esters of methacrylic acid is added in an amount of 10 to 40%. (A) A diester of neopentyl glycol represented by the following general formula (Formula 31) (wherein the C number of the esterified fatty acid is 10 to 20).

[0065]

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(B) Trimethylolpropane triester represented by the following general formula (Formula 32) (wherein the number of C of the esterified fatty acid is 10 to 20).

[0067]

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(C) A tetraester of pentaerythritol represented by the following general formula (Formula 33) (wherein the C number of the esterified fatty acid is 10 to 20).

[0069]

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(D) Polyacrylic acid represented by the following general formula (Formula 34) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0071]

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(E) Polymethacrylic acid represented by the following general formula (Formula 35) (where the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0073]

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6. 400 to 700 at a temperature of 40 ° C.
60-90% of a high-viscosity mineral oil having a kinematic viscosity of cSt is added to a polyol ester shown in the following (a), (b) and (c), a polyacrylic acid ester shown in (d) and a polyester shown in (e). The invention is characterized in that at least one oil agent selected from esters of methacrylic acid is added in an amount of 10 to 40%. (A) Monoesters or diesters of neopentyl glycol represented by the following general formula (Formula 36) (wherein the C number of the esterified fatty acid is 14 to 18).

[0075]

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(B) Monoesters, diesters or triesters of trimethylolpropane represented by the following general formula (Formula 37), wherein the C number of the esterified fatty acid is 14 to 18.

[0077]

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(C) Monoesters, diesters, triesters or tetraesters of pentaerythritol represented by the following general formula (Formula 38) (wherein the C number of the esterified fatty acid is 14 to 18).

[0079]

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(D) Polyacrylic acid represented by the following general formula (Chemical Formula 39) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0081]

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(E) Polymethacrylic acid represented by the following general formula (Formula 40), wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt. ester.

[0083]

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7. 400 to 700 at a temperature of 40 ° C.
60-90% of a high-viscosity mineral oil having a kinematic viscosity of cSt is added to a polyol ester shown in the following (a), (b) and (c), a polyacrylic acid ester shown in (d) and a polyester shown in (e). The invention is characterized in that at least one oil agent selected from esters of methacrylic acid is added in an amount of 10 to 40%. (A) A diester of neopentyl glycol represented by the following general formula (Formula 41) (wherein the C number of the esterified fatty acid is 14 to 18).

[0085]

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(B) Triesters of trimethylolpropane represented by the following general formula (Formula 42) (wherein the C number of the esterified fatty acid is 14 to 18).

[0087]

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(C) A tetraester of pentaerythritol represented by the following general formula (Formula 43) (wherein the C number of the esterified fatty acid is 14 to 18).

[0089]

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(D) Polyacrylic acid represented by the following general formula (Formula 44) (where the C number of the esterified alcohol is 1 to 3 and the kinematic viscosity at 40 ° C. is 20,000 to 100,000 cSt) ester.

[0091]

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(E) Polymethacrylic acid represented by the following general formula (Formula 45) (wherein the C number of the alcohol to be esterified is 1-3 and the kinematic viscosity at 40 ° C. is 20,000-100,000 cSt) ester.

[0093]

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[0094]

In the present invention, a mineral oil having a specific kinematic viscosity is used as a base oil, and an oil agent selected from esters of a specific polyol, esters of polyacrylic acid and esters of polymethacrylic acid is added to the base oil. By the interaction of, excellent mold lubricity at high temperature, excellent supply to the mold,
A mold lubricating oil having good properties of oil-water separation can be obtained.

[0095]

Hereinafter, examples of the present invention will be described in comparison with comparative examples. Example 1 As shown in FIG. 1, a continuous casting system including a continuous casting mold 1, a casting pit 3 in which a cast aluminum ingot 2 descends, and cooling water drops, and a cooling tower 4 for cooling water is used. Then, the lubricating oil shown in Table 1 was supplied to the inner wall of the mold 1 to continuously cast an aluminum alloy (A5182 alloy) melt M. The lubricity of the lubricating oil to the mold, the mold lubricity and the oil-water separation were evaluated. As casting conditions, industrially used conditions were applied.

The supply of lubricating oil to the mold is measured by measuring the amount of lubricating oil supplied and comparing the results with each other, setting the limit level at 8 that does not hinder industrial production to 8, and calculating the relative score based on this standard. The evaluation was made by attaching. The mold lubricity was evaluated by observing the surface of the cast aluminum ingot, and the degree of the defect was relatively evaluated based on the same standard as that for supplying the lubricating oil to the mold. The oil-water separation property was determined by collecting an emulsion composed of lubricating oil and cooling water that fell into the casting pit in FIG. 1 into a measuring cylinder, allowed to stand for 60 minutes, and measuring the oil content of the water tank after separation. The relative evaluation was based on Table 2 shows the evaluation results.

[0097]

[Table 1]

[0098]

[Table 2]

As shown in Table 2, in continuous casting of aluminum using the mold lubricant according to the present invention,
Excellent mold supply, mold lubricity, oil-water separation,
In each case, a rating of 8 or more was shown. The operation was carried out for 7 days using the continuous casting system shown in FIG. 1. The supply to the mold and the lubricity of the mold were maintained at practically acceptable levels, and the oil-water separation property was also good.

Comparative Example 1 As in Example 1, using the continuous casting system shown in FIG. 1 and supplying the mold lubricating oil shown in Table 3, the same casting test as in Example 1 was performed. In the same manner, the supply to the mold, the mold lubricity, and the oil-water separation property were evaluated.
Table 4 shows the evaluation results. In Table 3, those outside the conditions of the present invention are underlined.

[0101]

[Table 3]

[0102]

[Table 4]

As shown in Table 4, in test No. 1, the supply property to the mold was extremely good, but the viscosity of the lubricating oil also decreased due to the low viscosity of the mineral oil, and the The film thickness becomes thin and mold lubricity deteriorates. In Test No. 2, the viscosity of the lubricating oil was reduced due to the small amount of mineral oil, and the film thickness of the lubricating oil on the mold surface was reduced, resulting in reduced mold lubricity.
Also, the oil-water separation property is poor because the amount of mineral oil is small. Test N
In o.3, the supply to the mold was extremely good, but the lubricating oil in the mold decreased because the C number of the fatty acid in the polyol ester was small. Is also high, and the supply to the mold is not good.

In Test No. 5, since the fatty acid C in the polyol ester had a large C number, the compatibility with mineral oil was reduced, and the supply to the mold and the mold lubricity became poor. In Test Nos. 6 and 10, the viscosity of the lubricating oil also increased due to the high viscosity of the polyacrylate, and the compatibility with the mineral oil decreased. Therefore, the supply property to the mold and the mold lubricity are inferior. In Test No. 7, the viscosity of the lubricating oil also decreased due to the low viscosity of the polymethacrylic acid ester, and the thickness of the lubricating oil on the mold surface was reduced, resulting in poor mold lubricity. Test No.8
However, since the amount of the polyacrylic acid ester is large, the viscosity of the lubricating oil is increased, and the compatibility with the mineral oil is reduced. As a result, the supply to the mold and the lubricity of the mold are deteriorated.

In Test No. 9, the viscosity of the lubricating oil also decreased due to the low viscosity of the polyacrylic ester, and the lubricating oil film thickness on the mold surface became thin, resulting in inferior mold lubricity. In Test No. 11, the viscosity of the lubricating oil was increased due to the high viscosity of the polymethacrylate, and the compatibility with the mineral oil was reduced. As a result, the supply to the mold and the lubricity of the mold were inferior. In test No. 12, oil-water separation was not good because castor oil was used as the lubricating oil.

[0106]

As described above, according to the present invention, aluminum having excellent mold lubricating properties, good supply to the mold, hardly emulsifying when mixed with cooling water, and excellent oil-water separation properties. Provided is a mold lubricating oil for continuous casting. By applying the lubricating oil, the oil-water separation can reduce the BOD load in the cooling water, and the emulsion composed of the lubricating oil and the cooling water without using a large-scale treatment facility. Continuous casting of aluminum that enables the removal of lubricating oil from the steel.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an outline of an aluminum continuous casting system.

[Explanation of symbols]

 Reference Signs List 1 mold 2 aluminum ingot 3 casting pit 4 cooling tower M aluminum melt

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // C10N 20:02 40:20 (72) Inventor Toshihiko Uehara 5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industries, Ltd. ( 72) Inventor Eiichi Kashima 5-11-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industries, Ltd. (72) Inventor Koji Nagae 5-1-1-3 Shimbashi, Minato-ku, Tokyo Sumitomo Light Metal Industries, Ltd. (56) References JP-A-2-228393 (JP, A) JP-A-2-248497 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C10M 169/04 B22D 11 / 07 C10M 101/02 C10M 129/74 C10M 145/14 C10N 20:02 C10N 40:20 C10M 105/38 C10M 107/28

Claims (2)

(57) [Claims] 1. 300-2000 at a temperature of 40 ° C.
60-90% (wt%, the same applies hereinafter) of a high-viscosity mineral oil having a kinematic viscosity of cSt, a polyol ester shown in the following (a) to (c), a polyacrylic acid ester shown in the following (d) and e) at least one oily agent selected from the esters of polymethacrylic acid shown in
A mold lubricating oil for continuous casting of aluminum, characterized by being added. (A) Neopentyl glycol monoester or diester represented by the following general formula (Chemical Formula 1) However, the C number of the fatty acid to be esterified is 10-20. (B) Trimethylolpropane monoester, diester or triester represented by the following general formula (Chemical Formula 2) However, the C number of the fatty acid to be esterified is 10-20. (C) Monoester, diester, triester or tetraester of pentaerythritol represented by the following general formula (Chemical Formula 3) However, the C number of the fatty acid to be esterified is 10-20. (D) Polyacrylic acid ester represented by the following general formula (Formula 4) However, the C number of the alcohol to be esterified is 1 to 3,
Kinematic viscosity at 40 ° C is 20,000 to 100,000 cS
t. (E) Polymethacrylic acid ester represented by the following general formula (Formula 5) However, the C number of the alcohol to be esterified is 1 to 3,
Kinematic viscosity at 40 ° C is 20,000 to 100,000 cS
t. 2. A continuous casting method of aluminum, wherein the lubricating oil according to claim 1 is continuously supplied to an inner wall surface of a continuous casting mold to continuously cast aluminum or an aluminum alloy.