JPS6026680A - Composition for metal cleaning agent - Google Patents

Abstract

PURPOSE:To provide a compsn. for a metal cleaning agent for a steel plate having excellent performance by using a specific nonionic surface active agent or anionic surface active agent as an essential component and incorporating a carboxylic acid acid and the salt thereof, a 5-membered ring compd. and a quinoline deriv. having a hydroxyl group therein. CONSTITUTION:A compsn. for a cleaning agent having the compsn. which contains 1-40wt% a nonionic surface active agent having 3-18 HLB such as polyoxy ethylene alkyl ether and an anionic surface active agent such as alkyl aryl sulfonate or the like as an essential component, 1-50wt% the carboxylic acid expressed by the formula (L) or the salt thereof, 0.01-5wt% a 5-membered ring compd. having one N atom and one S atom or three N atoms such as benzotriazole and 0.01-5wt% a quinoline deriv. having a hydroxyl group such as oxyquinoline or the like is used as a compsn. for a cleaning agent for a steel plate whic is used in the final stand of a tandem mill and does not corrode the metal in contact therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal cleaning composition, and more particularly to a metal cleaning composition for use in a tandem mill, which is used in the last stand of a tandem mill to clean the metal of a steel plate without corroding the metal it comes in contact with. The present invention relates to a cleaning composition.

Metals are subject to corrosion when they come into contact with water, and particularly when the water they come into contact with is acidic or contains dissociated ions such as salt, the corrosion is particularly severe, causing steel sheet manufacturers to suffer great losses. Particularly in the process of cleaning metals, if the cleaning solution is alkaline, no major corrosion will occur, but if the cleaning solution is neutral, various dissociated ions in the cleaning solution will cause damage to the various components that make up the equipment. Corrosion of metals such as iron, steel, copper, and brass becomes a problem.

Various efforts have been made to prevent such corrosion. For example, benzotriazole, methylbenzotriazole, ethylbenzotriazole, benzothiazole, 2-mercaptobenzothiazole are copper rust inhibitors,
Oxyquinoline and its salts were developed as inhibitors in the pickling process of copper sheet production and are widely known. Even if highly corrosive metal cleaning agents are used alone or in combination, the effect of preventing metal corrosion is not sufficient.This is because the anticorrosive agent forms a film on the metal surface and adheres to it, but the Corrosion is likely to be accelerated by forming a localized anode, leading to pitting corrosion.Furthermore, when used in metal cleaning agents, corrosion inhibitors are It must not only be effective, but must not reduce the cleaning effect of the cleaning agent, must not cause oil stains or oil burns on the product, must not have any negative effects during the annealing process, and must not cause environmental pollution. There should be no problems.

The inventors of the present invention have conducted intensive studies to solve these problems, and have found that they can achieve the desired purpose by using a specific carboxylic acid (salt) together with a surfactant and an anticorrosive agent. This discovery led to the completion of the present invention.

That is, the present invention uses f(LB of 3 to 180, a nonionic surfactant and/or anionic surfactant as essential components, and the following general formula % formula % (wherein, X is N-H or N-(Of( , C00M or CH-C00M, R represents a saturated or unsaturated aliphatic hydrocarbon group having 4 to 18 carbon atoms, a phenyl group or a tolyl group, m8 and n represent an integer of 1 to 3,
M represents a cation); a 5-membered ring compound having one nitrogen atom and one sulfur atom or having three nitrogen atoms; and/or a quinoline derivative having a hydroxyl group. The present invention provides a metal cleaning composition containing the following.

According to the metal cleaning composition of the present invention, oil adhering to a steel plate can be thoroughly washed away, and it does not cause oil stains or oil burns, and does not affect the annealing process (and does not cause rust). In addition, pitting corrosion may be caused.Although the reason why the present invention exhibits such excellent effects is not clear, it is possible to use the specific carboxylic acid (salt) according to the present invention in combination with an anticorrosive agent. It is thought that the two act synergistically and dramatically improve corrosion resistance.The reason for this is that the anticorrosive agent is evenly distributed on the metal surface in the cleaning agent together with the carboxylic acid (salt). The thin film spreads over the surface of the metal, and the exposed part of the metal surface becomes non-existent. Therefore, incomplete parts of the film do not locally form an anode. It is also considered that pitting corrosion does not occur in an aqueous solution containing dissociated ions.

The carboxylic acid or its salt used in the present invention is as shown in the above general formula, but the cation M constituting the carboxylic acid salt is preferably:
It is an ion of an alkali metal, an aliphatic amine having 1 to 4 carbon atoms, ammonia, or an alkanolamine having 2 to 10 carbon atoms. Specific examples of M include methylamine,
Ethylamine, propylamine, butylamine, ethyleneamine, diethylenetriamine, ammonia, monoethanolamine, jetanolamine, triethanolamine, potassium, sodium and Nippon Nyukazai's amino alcohol 2, amino alcohol 2M, amino alcohol 2P, amino alcohol Examples include EA, amino alcohol MDA, and the like. Specific examples of the aliphatic hydrocarbon group in the general formula of the above carboxylic acid include linear or branched groups such as butyl, amyl, hexyl, octyl, decyl, lauryl, palmitel, myristyl, stearyl, and oleyl. Can be mentioned. Further, the following are typical examples of this carvone.

n-C+2H2a-CHCH2-COOI”Ja0ON
a The amount of the carboxylic acid (salt) used in the invention is 1 to 50% in the metal cleaning composition, preferably the amount of the 5-membered ring compound used and the quinoline derivative having a hydroxyl group. It is 1 to 50 times the amount.

In the present invention, examples of the five-membered ring compound having one yaron atom and one sulfur atom or having three nitrogen atoms include compounds having a thiazole ring and compounds having a triazole ring. Examples include benzotriazole, methylbenzotriazole, ethylbenzotriazole, benzothiazole, and 2-mercaptobenzothiazole. ,
Preferably it is 0.05 to 2% by weight.

In the present invention, examples of quinoline derivatives having a hydroxyl group include oxyquinoline, oxyquinoline sulfonic acid, and salts thereof. Examples of acids required for neutralization include known pyroic acids and organic acids such as sulfuric acid, nitric acid, hydrochloric acid, citric acid, phosphoric acid, acetic acid, oxalic acid, maleic acid, and p-toluenesulfonic acid. The amount of the quinoline derivative having a hydroxyl group used is 0.01 to 5% by weight, preferably 0.05 to 2% by weight in the metal cleaning composition.

The nonionic surfactant used in the metal cleaning agent of the present invention may be of any type as long as it has an HLB of 3 to 18, such as polyoxyethylene alkyl ether,
Polyoxyethylene alkylaryl ether, nrubitan fatty acid ester, fatty acid mono- and di-esters, etc. can be used, but preferred are the following general formulas (% formula %) (wherein R is a saturated ester having 6 to 18 carbon atoms) Or an aromatic group having an unsaturated aliphatic hydrocarbon group or a hydrocarbon group having 1 to 12 carbon atoms as a substituent.

n represents an integer of 1 to 50, preferably an integer of 3 to 30. ) and has an HLB of 3 to 18. Specific examples of these include polyoxyethylene hexyl ether, polyoxyethylene octyl ether, polyoxyethylene decyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl-f) L, polyoxyethylene myrist Ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene tolyl ether, polyoxyethylene xylenyl ether, holoxyethylene octylphenyl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene decyl phenyl ether, poly Examples include oxyethylene dodecylphenyl ether.

Regarding the number of moles of oxyethylene added to these compounds, as mentioned above, the HLB is limited within the range of 3 to 18, so for example, for polyoxyethylene lauryl ether, if the number of moles added is 50, the HLB is 18. .6
Therefore, it is excluded from the present invention. In the present invention, the amount of nonionic surfactant added to the metal cleaning composition is preferably 1 to 40%, more preferably 3 to 30%.
．． ii.

The anionic surfactants used in the present invention include alkylaryl sulfonates, alkanesulfonates, alkenesulfonates, sulfosuccinates, α-
Examples include sulfo fatty acid ester salts, fatty acid salts, alkyl sulfate ester salts, α-olefin sulfonic acid esters, polyoxyethylene alkyl x -f sulfate ester salts, polyoxyethylene alkylaryl sulfate ester salts, and the preferred ones are: It is expressed by the following formula.

R, -803 -18 saturated or unsaturated aliphatic hydrocarbon group, and X represents a cation) Specific examples of the aliphatic hydrocarbon group represented by R1 in the formula include hexyl, octyl, decyl, lauryl, myristyl, palmitel, and stearyl. Examples of aliphatic hydrocarbon groups include hexyl, octyl, decyl, lauryl, myristyl, palmityl, stearyl, etc.Anionic surfactants include The amount incorporated in the metal cleaning composition is preferably 1 to 40% by weight, more preferably 3 to 30% by weight.

Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited by these Examples.

The drug +1+ metal cleaning active ingredient used in the examples was prepared into the following composition and used.

Dotecyl alcohol ethylene oxide 9 mole adduct 2
0chi, sodium dodecyl alcohol sulfate 20
%, p-toluenesulfonic acid triethanolamine salt 2
0%, water 40ch.

A cleaning solution was prepared by diluting the above composition 100 times with water.

(2) The anticorrosive composition contains compound (5), compound (B) and (
C) was appropriately blended as shown in Table 1, 2% of a 9 mole adduct of dotecyl alcohol ethylene oxide was added as a solubilizer, and the mixture was balanced with water.

A test solution was prepared by adding 1.0% of the anticorrosive composition to the cleaning solution.

(3) The following chemicals were used as anticorrosive ingredients. The symbols are those shown in the examples.

0 compound (5) 0 compound (B) Methylbenzotriazole song) 2-Mercaptobenzothiazole 6V) 0 compound (C
) 8-oxyquinoline p-)luenesulfonate level) 87oxyquinoline 5-sulfonic acid sulfate level 0 (4) The test metal pieces used were commercially available copper pieces and the steel pieces used 5PCC-B material. . Size is 60 x 80 x 0.5 x m
It is.

Example 1 (Corrosion protection test method) 1! Adjust the cleaning solution to a bead strength of The test piece is suspended and immersed in the cleaning solution, stirred at 40 Orpm with a propeller-like stirrer, and kept at a temperature of 55°C for 5 hours. Corrosion resistance was evaluated by measuring weight loss after immersion. Since the weight after immersion is affected by the weight of the coating, it is necessary to measure it after removing the coating formed by the solvent.

Table 1 shows the evaluation results of the corrosion protection test.

(Results of Examples) Comparison of Comparison Nos. i and 2 shows that neutral cleaning agents are more corrosive to copper and steel than neutral water, but this may be due to the effects of local battery formation in ionized weirs, etc. Conceivable.

When Compound C) was used alone, the amount of corrosion of copper was reduced by 40 to 50 inches compared to Comparative Example 1 using only the detergent (hereinafter, the amount of corrosion reduction is expressed as a percentage of Comparative Example 1).Exp.

Al~4), in the case of compound (B) alone, it decreases to a factor of 20 (A5, 6). When compound (4) and (B) are used together, 1
A7,8), compounds (4) and (C)
When used in combination, it decreases to a factor of 50 (A9.10), but in addition, in this case, the surface of the steel specimen becomes very beautiful.

From this example, it can be seen that the effect of this anticorrosive composition is remarkable.The amount of corrosion on steel is 20% (A5°6) when compound (C) is used alone (A5°6), and 50% (A5°6) when compound (C) is used alone. Therefore, although the amount of corrosion is considerably reduced, pitting corrosion may be observed, and in such cases, using the tested specimen, adding a new cleaning solution to A and then conducting a corrosion protection test will reduce the amount of corrosion in the same way. When compounds (A) and (B) are used in combination, the amount of corrosion is reduced to 10 cm (A9-12), and interestingly, no pitting corrosion is observed on the steel piece, and in this case, the corrosion protection test is continued. As time passes, the amount of corrosion per unit time becomes smaller.
This is thought to be due to the effect of enabling uniform spreading of B) and (C) and assisting the formation of an adsorbed film with very few missing parts.

Graves 13 to 20 show cases in which compounds (A), (13+, and (C)) are used in combination, but the corrosion resistance against copper and steel is 10%, and there is no pitting corrosion against steel. However, the anticorrosive composition of the present invention has a very remarkable anticorrosion WJ.
It can be seen that it shows g. The present anticorrosive composition is characterized in that it does not reduce the cleaning properties of metal cleaning agents. Compound (5
) The amount of corrosion on copper and steel alone is 80% compared to the comparative example.
It is.

Below margin

Claims (1)

[Claims] 1. A nonionic surfactant and/or anionic surfactant having an HLB of 3 to 18 are essential components, and the following general formula % formula % (wherein, X is N-14 or N CH2+-FVCOOM
or CH-COOM, R represents a saturated or unsaturated aliphatic hydrocarbon group having 4 to 18 carbon atoms, a phenyl group or a tolyl group, m and n represent an integer of 1 to 3, and M represents a cation. carboxylic acid or its salt represented by ); a 5-membered ring compound having one nitrogen atom and one sulfur atom or having three nitrogen atoms;
Or) Does it contain a quinoline derivative with a hydroxyl group? Characteristic metal cleaning composition. Claim 1, wherein the 2.5-membered ring compound is one or more selected from the group consisting of benzotriazole, methylbenzoazole, ethylbenzotriazole, benzothiazole, and 2-mercaptobenzothiazole. Metal cleaning composition. 3. M is an alkali metal, an aliphatic amine having 1 to 4 carbon atoms,
The metal cleaning composition according to claim 1 or 2, which is an ion of ammonia or alkanolamine.