JPH0312118B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention provides high lubricity, high mill cleanliness rolling oil,
That is, it relates to a cold rolling oil for steel sheets that has excellent lubricity and annealing properties. (Conventional technology) The cold rolling oil used for thin steel sheets can be based on animal or vegetable oils (beef tallow, lard, soybean oil, rapeseed oil, palm oil, coconut oil, etc.) or mineral oil as the base oil. It is broadly divided into those that do. In recent years, high-speed rolling, high-reduction rolling, and mill-clean rolling have been trending toward energy conservation and improved production efficiency. Rolling oils that use animal or vegetable oils as base oils are suitable for high-load, high-speed rolling, but if the oil deposits on a cold-rolled steel plate are directly annealed without degreasing, the steel plate will be damaged during the annealing process. Causes surface stains. In other words, it has excellent lubricity but is unsuitable for mill cleanliness. On the other hand, when cold rolling is performed using a rolling oil based on mineral oil, no surface stains occur even when the cold thin steel sheet is directly annealed, and the mill cleanliness is excellent. However, it lacks high load and high speed rolling properties. Generally, rolling oils based on mineral oils are made using animal/vegetable oils, fatty acids (cabric acid, lauric acid, myristic acid, stearic acid, oleic acid, linolenic acid, etc.) or oil chemistry '73 to improve rolling lubricity.・Esters (synthetic esters such as monoesters, diesters, polyol esters, etc. whose alcohol component is trimethylolpropane, pentaerythritol, 2-ethylhexyl alcohol, etc.) as listed on pages 695 to 706 of the November issue, etc. Oiliness improvers are added and used, but the amounts added are adjusted within a narrow range to the minimum necessary in order to maintain mill cleanliness. As mentioned above, various studies have been conducted on cold rolling oils that can simultaneously satisfy high lubricity and high mill cleanliness (for example, JP-A No. 56-135600, JP-A No. 59-Sho.
80498) Currently, there is no one that is suitable for both. (Problems to be solved by the invention) The present invention is a cold rolling oil for steel that contributes to improving production efficiency through energy saving and process saving, and is stable against heat and mechanical shear generated under high speed and high pressure. It is also stable against chemical reactions such as oxidation, decomposition, and polymerization. In addition, the rolling oil is easily volatilized during the annealing process without producing thermal decomposition residues, and has both steel sheet surface cleanliness (mill cleanliness) and high lubricity. (Means and effects for solving the problems) The present invention provides high lubricity and high mill cleanliness in cold rolled steel parts whose main component is synthetic ester, which is a reaction product of amino alcohol and fatty acid. This makes it possible to effectively roll thin steel sheets and annealing cold rolled steel sheets without degreasing them. The synthetic esters referred to in the present invention are molecularly designed and synthesized for such purposes. In recent years, synthetic esters have been used as rolling oil additives or as base oils, but few of the synthetic esters used in cold rolling oils have been synthesized for this purpose, and are used in engine oils and hydraulic oils. Alternatively, it is often selected from existing synthetic esters used as other lubricants, and it is not possible to fully satisfy both high lubricity and high mill cleanliness. The synthetic ester of the present invention is used for cold rolling oil.
That is, it has the characteristics of both high lubricity and high mill cleanliness, and has the following molecular design. That is, the general formula (However, _R1 : an alkyl group having 1 or more carbon atoms, an alkenyl group, a phenyl group, a cyclohexyl group, X:
H or CH ₃ , n = integer of 1 to 3) Any of the indicated amino alcohols and carbon number 6
This cold rolling oil for steel sheets is characterized by containing at least one of the above esterification products with fatty acids. The nitrogen-containing esterified product can be obtained by the esterification reaction of a tertiary amine such as triethanolamine, tripropanolamine, alkyldiethanolamine, dialkylethanolamine, etc. with an amino alcohol and a fatty acid. Fatty acids include hexanoic acid, octanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, montanic acid, palmitoleic acid, oleic acid, erucic acid, ricinoleic acid, and hydroxystearin. Acid, linoleic acid, linolenic acid, isooctylic acid,
Straight chain and side chain saturated and unsaturated natural and synthetic fatty acids having 6 or more carbon atoms such as isodecanoic acid, isolauric acid, isomyristic acid, isopalmitic acid, isostearic acid, and isoaracic acid can be used. The reason why the fatty acids are limited to those having 6 or more carbon atoms is because fatty acid esterification products having less than 6 carbon atoms have a small degree of improvement in lubricity when cold rolling a steel plate. On the other hand, although the upper limit of the number of carbon atoms in fatty acids is not regulated,
Generally, carbon atoms having 30 or less carbon atoms are preferred as they are industrially inexpensive and available. On the other hand, R ₁ in general formulas (2) and (3) is methyl, ethyl,
Alkyl and alkenyl groups having 1 or more carbon atoms such as propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, hexadecyl, octadecyl, phenyl and cyclohexyl groups can be used. There is no upper limit to the number of carbon atoms in alkyl and alkenyl groups, but it is preferably 30 or less, similar to fatty acids. Further, in the general formulas (1), (2), and (3), the number of n in ethylene oxide and propylene oxide is preferably 1 to 3. If n is 4 or more, the degree of improvement in lubricity during cold rolling of a steel sheet, which is one of the objects of the present invention, is not improved to a large extent, and it is also unfavorable for annealing properties. Although the molar ratio of each amino alcohol of general formulas (1), (2), and (3) to the fatty acid is not particularly limited, it is suitable for use as a cold rolling oil for steel sheets with higher lubrication and higher milling properties. Ester in which 50% or more of the hydroxyl groups in one molecule of the trivalent amino alcohol of general formula (1) or the divalent amino alcohol of formula (2) are esterified with a fatty acid having 6 or more carbon atoms in order to achieve cleanliness. Chemical compounds are preferred. When the synthetic ester of the present invention is used as a rolling oil, the synthetic ester alone can also be used as the rolling oil. It can also be used in combination with other base oils, such as mineral oils and animal/vegetable oils.
It is also possible to add an emulsifier to these and use them as an emulsion liquid. In addition, it can also be used in combination with emulsifiers, fatty acids, antioxidants, and corrosion inhibitors that are commonly used as additives in mineral oils, animal/vegetable oils, or practical rolling oils that are generally used as base oils. When the synthetic ester compound of the present invention is used in combination with other base oils etc., the effect is observed when it is added in an amount of 1% by weight or more, but the content should be 5% by weight or more, preferably 20% by weight or more. The characteristics become stable. Furthermore, synthetic esters which are reaction products of amino alcohols and fatty acids represented by general formulas (1), (2) and (3) of the present invention can also be used in combination. The nitrogen-containing esterification product of the present invention can be synthesized by a conventional method without a catalyst or in the presence of a catalyst, but the synthesis method is not particularly limited. An example of the synthesis method will be shown below. Synthesis example Triethanolamine was placed in a 4-necked flask equipped with a stirrer, thermometer, nitrogen gas blowing tube, and water separator.
298g (2 mol), coconut oil fatty acid 125g (5.8 mol)
, add 5% of the charged amount under non-catalytic conditions using xylene as a refluxing solvent, stir well, and mix the mixture.
The reaction was carried out at 160-230°C until the calculated amount of water was distilled off. The required time was 8 hours. After the reaction was completed, xylene was distilled off under reduced pressure, and the mixture was decolorized and filtered using activated clay to obtain a yellow liquid. Yield 1402
g, and the acid value was 1.2. Hereinafter, synthetic esters were produced in the same manner. The properties of the obtained synthetic ester compounds are shown in Tables 1 to 3. (Example) When mineral oil or palm oil, which is used as the base oil of practical rolling oil, is blended with emulsifiers, fatty acids, antioxidants, etc., which are commonly used as additives, and synthetic ester, which is the rolling oil of the present invention, The lubricity and annealing properties of the resulting rolling oil composition were evaluated. Emulsion rolling is performed using a two-high roll rolling mill, rolling material (SPCC) 1.2 x 20 x 200 mm with an oil concentration of 3%,
The rolling lubricity was evaluated by measuring the rolling load at a rolling reduction of 40% at a bath temperature of 50°C. As for annealing properties, tens of steel plates rolled with the sample emulsion liquid were stacked together, fixed with a narrow steel strip, and annealed in a small annealing furnace. The heating conditions during annealing were HNX gas (H ₂ :5
%) In an atmosphere of 120m ³ /min, the temperature increase rate is 10℃/min.
The mixture was heated to 600°C (minimum), held at 600°C for 1 hour, and then allowed to cool. Thereafter, a cellophane tape was attached to the surface of the steel plate, and the surface deposits were collected and attached to white paper to visually determine the degree of contamination, and the cleanliness of the steel plate surface was evaluated. The test results are summarized in Table 4, and the symbols in the table are the same as in Tables 1 to 3.

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[Table] (Effects of the invention) The nitrogen-containing synthetic ester compound obtained from the reaction of the fatty acid and amino alcohol of the present invention is intended to be used as a rolling lubricant for steel plates, and its molecular design has been carried out taking into consideration the necessary conditions for this purpose. Unlike existing synthetic esters that are used as cold rolling oil or as additives, it is possible to improve rolling lubricity for steel sheets, compared to when conventional palm oil is used as a base oil. In comparison, it brings about energy and resource saving effects such as reduced power costs. In addition, it has excellent annealing properties, making it possible to omit the usual electrolytic degreasing and reducing equipment costs.

Claims (1)

[Claims] 1. General formula (However, R ₁ : Alkyl group having 1 or more carbon atoms, alkenyl group, phenyl group, cyclohexyl group, X: H
or CH ₃ , n = an integer of 1 to 3) Contains at least one esterification product of an amino alcohol represented by general formula (1), (2) or (3) and a fatty acid having 6 or more carbon atoms. Cold rolling oil for steel plates. 2. Claim 1, wherein the esterified product is one in which 50% or more of the hydroxyl groups in one molecule of the amino alcohol of general formula (1) or (2) are esterified with a fatty acid having 6 or more carbon atoms. cold rolling oil for steel plates.