JPS6316468B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a water-soluble tempering liquid for cold-rolled steel sheets, and more particularly to a novel tempering liquid that is not likely to be carcinogenic. Generally, soft mineral oil or a water-soluble tempering liquid is used when cold-rolled steel sheets that have undergone an annealing process are temper-rolled. The purpose of use of these temper rolling fluids is to prevent rust immediately before the temper rolling process and the subsequent rust prevention treatment process.
and cleaning of carbon generated during the annealing process or iron powder generated during temper rolling. Soft mineral oil has a low coefficient of friction, which not only makes it difficult to transfer onto the surface of a steel plate using a dull roll, but also has drawbacks such as poor cleanability. On the other hand, water-soluble conditioning liquids have improved the above-mentioned drawbacks, but have other problems. That is, conventional water-soluble conditioning fluids are mainly composed of _NaNO2 and alkanolamines, or are mixed with organic anticorrosion additives such as para-nitrobenzoic acid, para-aminobenzoic acid, long-chain fatty acids, and surfactants. Because NaNO ₂ reacts with alkanolamines, the resulting nitroso compound may be carcinogenic, so denitrification has been desired. An object of the present invention is to provide a water-soluble conditioning liquid that has excellent performance required as a conditioning liquid and is harmless to the human body. The present inventors have completed the present invention as a result of research on denitrification of water-soluble conditioning liquids, and the gist of the invention is to use benzoic acid nitro group-substituted compounds and/or benzoic acid amino group substituted compounds. Cold rolling characterized by containing a substituted compound, an alkyl group substituted compound of benzoic acid having 10 or less carbon atoms, a primary amine, an aliphatic carboxylic acid having 10 or less carbon atoms, and a surfactant. Found in water-soluble tempering fluid for steel plates. The nitro group-substituted compounds of benzoic acid used in the present invention include ortho-, meta-, and para-nitrobenzoic acids, and the amino-group-substituted compounds of benzoic acid include ortho-, meta-, and para-aminobenzoic acids. Examples of the group-substituted compound include tertiary butylbenzoic acid, peptylbenzoic acid, paranonylbenzoic acid, paraoctylbenzoic acid, and parapropylbenzoic acid. As the primary organic amine, for example, ethylamine, monoisopropanolamine, monoethanolamine, octylamine, pentylamine, hexylamine, etc. can be used. Examples of aliphatic carboxylic acids having 10 or less carbon atoms include acrylic acid, 2-ethylhexanoic acid, caprylic acid, sebacic acid, maleic acid, cyclohexylcarboxylic acid, glutaric acid, and adipic acid. Furthermore, as the surfactant, any of nonionic surfactants, anionic surfactants, cationic surfactants, or amphoteric surfactants can be used, such as sodium alkylbenzene sulfonate, alkyl ester acids, alkylphenol-based or higher alcohol-based surfactants. Polyoxyethylene ether, a sulfuric ester salt of an ether type nonionic surfactant, or a sulfonic acid salt thereof is used. An antirust effect is produced by the combined use of a compound substituted with a nitro group or an amino group in benzoic acid, a compound substituted with an alkyl group having 10 or less carbon atoms in benzoic acid, and a primary amine. When a primary organic amine is added in an amount equal to or more than the same mole relative to the above substituted compound of benzoic acid, a water-soluble amine salt of the benzoic acid substituted compound is formed, and this salt has a good antirust effect. Even if the primary organic amine is added in excess of the above-mentioned equimolar amount, it will not have any harmful effect because the primary organic amine itself has a rust-preventing effect. Note that the number of carbon atoms in the substituted alkyl group of benzoic acid is 11.
If it is more than that, the coefficient of friction becomes excessive, which is inappropriate. The aliphatic carboxylic acid having 10 or less carbon atoms further increases the rust-preventing effect when used in combination with the benzoic acid-substituted compound and the primary organic amine, and the addition of this aliphatic carboxylic acid further enhances the anti-corrosion effect of the present invention. The liquid is
It was able to exhibit the same anti-corrosion effect as conventional tempering liquids whose main components are NaNO ₂ and alkanolamine. In addition, aliphatic carboxylic acids have a carbon number of
Anything over 11 has an excessive friction coefficient and is inappropriate. The amount of aliphatic carboxylic acid added is the total amount of the benzoic acid substituted compound and primary organic amine from 1 to 50.
The amount is adjusted in the range of 0.1 to 10 parts by weight, taking into account the rolling conditions of the temper rolling process, etc. If the amount of aliphatic carboxylic acid added is too small, the antirust ability will be insufficient, and if it is too large, the coefficient of friction will be excessive, so the above range is appropriate. The surfactant has a cleaning effect, and its type and amount are adjusted depending on the conditions of the temper rolling process. Usually the amount added is less than 5%. Next, examples will be given to demonstrate the excellent effects of the present invention, but the present invention is not limited thereto. Example An example of the present invention having the configuration shown in Table 1 and a conventional conditioning stock solution containing NaNO ₂ (comparative example) were diluted with water to make a water-soluble conditioning solution with a concentration of 10% by weight, Using rolling mill 4Hi, rolling speed 1000mpm,
SPCC material with a thickness of 1.2 mm and a width of 917 mm was temper-rolled at a rolling reduction of 1.2%, and 100 mm x 100 mm specimens were taken to evaluate rust prevention, paint adhesion, compatibility with rust prevention oil, and In addition to measuring degreasing properties, detergency and friction coefficient were also measured. The measurement was carried out using the method described below. Rust resistance: 10 specimens in contact, atmospheric condition 35
The rusted area ratio was observed after being left for 56 hours at ℃ x 70% RH. Paint adhesion: Apply paint #505 to the specimen and heat at 160℃
After drying for 20 minutes, the cross-cut without peeling was measured using a checkerboard peel test. Compatibility with rust preventive oil: Apply rust preventive oil to the specimen,
Tighten with a load of Kg/cm ² or more, 50℃ x R.
The discoloration of the rust preventive oil was observed after it was left standing in a constant temperature and humidity chamber at 95% H. for 30 days. Degreasing property: Dip the specimen in the conditioning solution for 5 seconds, drain it, and pack it in kraft paper after contact.
After standing in a constant temperature and humidity chamber at ℃ x 90% RH for 7 days, it was washed under the following conditions and its water wettability was observed. Cleaning conditions: Cleaning liquid: Clear water, Pressure: 1Kg/cm ² , Temperature: Room temperature, Time: 30 seconds, Nozzle: Full jet type Cleaning performance: 100% tempering liquid in a 30mm diameter stopper cylinder
ml, 1 g of carbon black was added thereto, and after shaking up and down 30 times, the mixture was left standing in a constant temperature bath at 25±1° C., and the dispersion status was observed after 1 hour. Friction coefficient: Lubrication test The friction coefficient was measured using a Soda pendulum type oil tester. The above measurement results are shown in Table 1.

【table】

[Table] The example does not contain NaNO ₂ and has a non-carcinogenic composition, and compared to the conventional water-soluble conditioning solution (comparative example),
It has been clearly recognized that it has excellent rust prevention and degreasing properties, the same or better paint adhesion, and the same excellent performance in terms of compatibility with rust preventive oil, cleanability, and coefficient of friction. It greatly contributes to practical use as a water-soluble tempering liquid for inter-rolled steel sheets.

Claims (1)

[Claims] 1 Benzoic acid nitro-substituted compound and/or benzoic acid amino-substituted compound, benzoic acid substituted compound with alkyl group having 10 or less carbon atoms, primary organic amine, and aliphatic carboxylic acid having 10 or less carbon atoms and a surfactant.