JP2009057464A - Detergent composition for batch-annealed steel strip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detergent composition for a batch-annealed steel strip for improving detergency and reducing the degree of adhesion of a batch-annealed steel strip in a manufacturing process of the steel strip including a cleaning process and a batch annealing process. <P>SOLUTION: The detergent composition for the batch-annealed steel strip contains 0.1-26 wt.% silicate (a), 0.15-15 wt.% specific ampholytic surfactant (b), one or more kinds of nonionic surfactants (c) selected among alkylene oxide adducts of 4-24C alcohol, one or more compounds (d) selected among specific carboxylate compounds shown by general formulas (d1) to (d2), and water. The total amount of the components (b) and (c), and a weight ratio of the component (b) to the component (c) are each within a specific range. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cleaning composition for batch-type annealed steel strip and a steel strip manufacturing method having a cleaning step using the composition.

  The steel strip needs to be cleaned of dirt such as rolling oil, hydraulic oil, iron powder, and iron soap generated and adhered during rolling, and then subjected to annealing for imparting workability. Here, annealing is annealing or annealing, and refers to the process of heating to a suitable temperature once, holding it there, and then gradually cooling (Chemical Dictionary 1 volume P208 (Showa 56)), iron or steel. The purpose is to soften the crystal, to adjust the crystal structure or to remove internal stress.

  The annealing methods include batch annealing and continuous annealing. Among these, the batch annealing has a problem of adhesion or seizure of a steel strip, which contributes to a decrease in yield.

  In order to prevent such adhesion, it is known that silicon deposited on the surface of the steel strip is effective when electrolytic cleaning (electrolytic cleaning) is performed using a cleaning agent containing sodium silicate. At that time, the surface state (roughness) of the steel strip surface is one of the factors affecting the silicon adhesion amount.

Patent Document 1 discloses a concentrated alkaline cleaning agent with a specific concentration that is used for the removal of dirt such as oily substances adhering to the metal surface and dirt such as metal powder in the previous stage of an annealing process or the like. ing. Patent Document 2 discloses a metal detergent composition containing an alkali base, a surfactant, and a compound selected from a specific group. Further, Patent Document 3 discloses a detergent composition for hard surfaces such as alkali agents, specific nonionic surfactants, and metals containing amphoteric surfactants.
Japanese Patent Application Laid-Open No. 11-181587 JP-A-60-121284 JP 2006-219552 A

  Patent Document 1 relates to a suspension-type cleaning agent using an alkali agent at a high concentration, and it is difficult to say that it discloses a technique in a mode suitable as a cleaning agent having an adhesion reduction effect for annealing. Moreover, it has been found that when an alkali agent is used in the range as actually disclosed in the examples of Patent Document 1, the composition is extremely solidified and cannot be practically used. Therefore, in patent document 1, what has sufficient stability of a washing | cleaning agent, and was excellent in the washability and the adhesiveness reduction effect of the steel strip after batch type annealing cannot be obtained. On the other hand, with respect to Patent Document 2, further improvement is desired for the cleaning property and the effect of reducing the adhesion of the steel strip after batch annealing. In Patent Document 3, there is no mention of the problem of achieving both the cleanability of the steel strip before annealing and the effect of reducing the adhesion of the steel strip after batch annealing.

  An object of the present invention is to provide a cleaning composition for a batch-type annealed steel strip, which can reduce the degree of adhesion of the steel strip after the batch-type annealing and the high cleanability in the steel strip production process including the cleaning step and the batch-type annealing. It is providing the steel strip manufacturing method which has the washing | cleaning process which uses a composition.

  The present invention relates to silicate (a) [hereinafter referred to as component (a)] 0.1 to 26% by weight, one or more amphoteric surface actives selected from compounds represented by the following general formulas (b1) to (b3). Agent (b) [hereinafter referred to as component (b)] 0.15 to 15% by weight, one or more nonionic surfactants selected from alkylene oxide adducts of alcohols having 4 to 24 carbon atoms (c) [hereinafter, Component (c)], one or more compounds (d) selected from the compounds represented by the following general formulas (d1) to (d2) [hereinafter referred to as component (d)], and batch-type annealing containing water A steel strip cleaning composition, wherein the total content of component (b) and component (c) is 0.16 to 18% by weight, and the weight ratio of component (b) and component (c) (b ) / (C) is 100/1 to 100/150 for batch annealing steel strip Compositions relating [hereinafter sometimes referred to as concentrate-based Composition.

(In the formula, R ¹ represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 20 carbon atoms, and R ² and R ³ each represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 3 carbon atoms.)

(In the formula, R ⁴ represents an alkyl group or an alkenyl group having 1 to 30 carbon atoms.)

(In the formula, R ⁵ represents an alkyl group or alkenyl group having 1 to 20 carbon atoms.)

^{_{-X- R 1d (CH 2) m}} COOM 1 (d1)
R ^2d -COOM ² (d2)
[Wherein, R ^1d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 4 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and X represents a group> NH, > N (CH ₂ ) _n COOM ¹ or> CHCOOM ¹ R ^2d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 3 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. M ¹ and M ² each represent a hydrogen atom, an alkali metal, an aliphatic ammonium group having 1 to 4 carbon atoms, an ammonium group or an alkanol ammonium group, and m and n each represent an integer of 1 to 3. ]

  The present invention also relates to one or more amphoteric surfactants (b) 0 selected from silicates (a) 0.1 to 4.5% by weight and compounds represented by the following general formulas (b1) to (b3). .15 to 1.3 wt% [hereinafter referred to as component (b)], one or more nonionic surfactants selected from alkylene oxide adducts of alcohols having 4 to 24 carbon atoms [hereinafter referred to as component (c) )], And a batch-type annealed steel strip cleaning composition containing water, wherein the total content of component (b) and component (c) is 0.16 to 1.5% by weight, and Cleaning composition for batch-type annealed steel strip having a weight ratio (b) / (c) of component (b) and component (c) of 100/1 to 100/150 [hereinafter sometimes referred to as a dilute composition] ] Concerning.

  Moreover, this invention is a steel strip manufacturing method which has a batch type annealing process after an electrolytic cleaning process, Comprising: Steel strip manufacture which uses the cleaning composition for batch type annealing steel strips of the said invention in an electrolytic cleaning process Regarding the method.

  According to the present invention, in a manufacturing process of a steel strip including a cleaning process and batch-type annealing, a cleaning composition for a batch-type annealed steel strip that can reduce high cleaning properties and adhesion of the steel strip after batch-type annealing, and the concerned The steel strip manufacturing method which has the washing | cleaning process using a composition can be provided. In addition, such high cleaning properties and the effect of reducing the adhesion of the steel strip after batch annealing are not impaired even after storage, and even when stored in the state of a concentrated composition, the effect of the present invention Is maintained.

  The cleaning composition for batch-type annealed steel strips according to the present invention is a composition containing a combination of silicate and a specific amphoteric surfactant. It has been completed by utilizing the fact that it has both excellent and excellent compatibility in reducing the adhesion of the steel strip.

  The present invention is mainly a concentrated composition that is excellent in storage stability and is distributed and stored in a high concentration composition and is used by diluting at the time of use, and a dilute composition that is prepared mainly at the site of use and used as it is. It provides things.

[Component (a)]
Silicic acid includes orthosilicic acid (H ₄ SiO ₄ ), metasilicic acid (H ₂ SiO ₃ ), mesodisilicic acid (H ₂ Si ₂ O ₅ ), mesotrisilicic acid (H ₄ Si ₃ O ₈ ), mesotetrasilicic acid ( H ₆ Si ₄ O ₁₁ ) and the like, and the component (a) of the present invention is a salt such as a sodium salt or potassium salt of these silicic acids. Generally, nM ₂ O · mSiO ₂ (n and m are integers, M Is a compound represented by the general formula: As the component (a), orthosilicic acid, metasilicic acid, alkali metal salts of sesquisilicic acid, especially sodium salt and potassium salt, sodium salt and potassium salt of orthosilicic acid, and sodium salt of orthosilicic acid are more preferable. Further, as the component (a), 1 No. of sodium silicate _{(Na 2 O · 2SiO · aq} ), 2 No. of sodium silicate _{(2Na 2 O · 5SiO · aq} ), 3 No. of sodium silicate _{(Na 2 O · 3SiO · aq} ) Sodium silicate which can be obtained as (JIS K 1408), in particular, No. 2 sodium silicate is also suitable. Of these silicates, No. 2 sodium silicate is most preferred.

  The content of the component (a) is a concentrated system in the cleaning composition for batch-type annealed steel strips of the present invention from the viewpoint of reducing the adhesion of the steel strip after batch-type annealing and one-component transparency during concentration. In the composition, it is 0.1 to 26% by weight, preferably 0.3 to 24% by weight, and more preferably 0.5 to 20% by weight. Moreover, in a diluted composition, it is 0.1 to 4.5 weight%, 0.4 to 3.0 weight% is preferable and 1.0 to 2.0 weight% is more preferable.

  Silicate makes the cleaning composition for steel strips alkaline, removes dirt such as oily substances on the steel strip and dirt such as metal powder, and at the same time acts in combination with a specific surfactant described later. This reduces the adhesion of the steel strip after batch annealing.

[Component (b)]
Component (b) of the composition of the present invention is one or more amphoteric surfactants selected from the compounds represented by the general formulas (b1) to (b3). In the general formula (b1), R ¹ is a hydrogen atom or an alkyl or alkenyl group having 1 to 20 carbon atoms, preferably a hydrogen atom, an alkyl or alkenyl group having 1 to 14 carbon atoms, R ² or R ³ is Respectively represent a hydrogen atom or an alkyl group or alkenyl group having 1 to 3 carbon atoms. In the general formula (b2), R ⁴ represents an alkyl group or alkenyl group having 1 to 30 carbon atoms, preferably 1 to 14 carbon atoms. In the general formula (b3), R ⁵ represents an alkyl or alkenyl group having 1 to 20 carbon atoms, preferably 1 to 14 carbon atoms. In addition, when these groups are alkenyl groups, the lower limit of the carbon number is 2. Component (b) further promotes the removal of dirt such as oily substances on the steel strip and dirt such as metal powder by the action of the combination with the silicate described above, and at the same time, the adhesion of the steel strip after batch annealing. Has the effect of reducing.

  The content of component (b) is 0.15 to 15 for the concentrated composition in the cleaning composition for batch-type annealed steel strip of the present invention, from the viewpoint of reducing the adhesion of the steel strip after batch-type annealing. % By weight, preferably 0.17 to 13% by weight, more preferably 0.2 to 12% by weight. In the dilute composition, the content of the component (b) is 0.15 to 1.3% by weight, and preferably 0.2 to 1.0% by weight.

[Component (c)]
The composition of the present invention contains, as component (c), one or more nonionic surfactants selected from alkylene oxide adducts of alcohols having 4 to 24 carbon atoms, preferably monohydric alcohols having 4 to 24 carbon atoms. To do.

  Component (c) reinforces the effect of exfoliating and inhibiting reaggregation of oil components on the steel strip surface, dirt such as oily substances on the steel strip, dirt such as metal powder, or derived dirt.

  In particular, the component (c) is preferably an alkylene oxide adduct of a C 4-24 alcohol, and further a C 4-24 monohydric alcohol.

  Component (c) is preferably one having an HLB of 4.3 to 8.2, more preferably 5 to 7.9 as determined by the Davis method.

In addition, HLB of a component (c) is HLB by the Davis (Davies) method, and is a value represented by the following formula, and the number of hydrophilic groups and the number of lipophilic groups in the following formula are “new edition surfactants” The values described in Table 5-1-3 on page 235 of “Handbook”, Engineering Books Co., Ltd., May 1, 1996 are adopted.
HLB = Σ [base number of hydrophilic group of component (c)] + Σ [base number of lipophilic group of component (c)] + 7

  Among the component (c), examples of the alkylene oxide adduct of an alcohol having 4 to 24 carbon atoms include one or more nonionic surfactants selected from compounds represented by the following general formula (c1).

R ^1c —O— (AO) _m H (c1)
(In the formula, R ^1c is a linear or branched alkyl group or alkenyl group having 5 to 20 carbon atoms, AO is an oxyalkylene group having 2 to 4 carbon atoms, and m is an average addition mole number of more than 0 and 20 or less. And the m AOs may be the same or different.)

  The following are mentioned as a nonionic surfactant of general formula (c1).

R ^1c —O— (AO) _{m ′} H (c1-1)
(In the formula, R ^1c and AO are the same as above, m ′ is a number of 1 or more and less than 5 indicating the average number of added moles, and m ′ AOs may be the same or different.)

_{^{-O- R 1c (EO) x2 (}} PO) y2 (EO) x3 H (c1-2)
(In the formula, R ^1c is the same as above, EO is an oxyethylene group, PO is an oxypropylene group, x2 and x3 are average addition moles of oxyethylene groups, and y2 is an average addition mole number of oxypropylene groups. , X2 is 1 or more, x3 is 0 or more, y2 is 0 or more, and satisfies 5 ≦ x2 + y2 + x3 ≦ 20, and (EO) _x2 , (PO) _y2 and (EO) _x3 are blocks in this order. Added.)

In the formula (c1-1), R ^1c is a linear or branched alkyl group or alkenyl group having 5 to 20 carbon atoms, preferably 5 to 16 carbon atoms, more preferably 5 to 12 carbon atoms, still more preferably. Is a linear or branched alkyl or alkenyl group having 6 to 10 carbon atoms. Examples of the alkyl group include hexyl group, octyl group, 2-ethylhexyl group, decyl group, sec-decyl group, lauryl (dodecyl) group, sec-lauryl group, myristyl group, cetyl group and stearyl group. . Within this range, the cleaning performance at low temperatures (50 ° C. or lower) is excellent, but from the viewpoint of suppressing foaming, a branched chain is preferred, and a 2-ethylhexyl group is most preferred.

  In Formula (c1-1), AO represents an oxyalkylene group having 2 to 4 carbon atoms such as an oxyethylene group, an oxypropylene group, or a tetramethylene group, and is preferably an oxyethylene group or an oxypropylene group. m ′ represents the average number of moles added of the oxyalkylene group, and from the viewpoint of obtaining good detergency at a low temperature (50 ° C. or less), it is a number of 1 or more and less than 5, and the lower limit is preferably 2 or more. 3 or more is more preferable, and the upper limit is further preferably 4 or less. The m ′ AOs may be the same or different. If they are different, any of block addition, random addition, alternating addition, etc. may be used.

In formula (c1-2), R ² is preferably an alkyl group or alkenyl group having 8 to 16 carbon atoms, more preferably 10 to 14 carbon atoms. x2 is 1 or more and 20 or less, preferably 5 to 16, and more preferably 5 to 12. x3 is 0 or more and 19 or less, preferably 0 to 10, and more preferably 0 to 8. y2 is 0 or more and 19 or less, but 1 or more is preferable from the viewpoint of foam suppression, 2 to 13 is more preferable, and 2 to 8 is still more preferable. Further, x2 + y2 + x3 is 5 or more and 20 or less, preferably 8 or more and 18 or less, more preferably 10 or more and 16 or less, from the viewpoint of improving the repetitive cleaning property. When the sum of x2 + y2 + x3 is 5 or more, the emulsifying power of the oil can be increased, and further good repeatability can be obtained. Further, when the nonionic surfactant represented by the formula (c1-1) is used in combination when washing at a low temperature of 50 ° C. or less when the sum of x2 + y2 + x3 is 20 or less, the oil stain of the nonionic surfactant It is possible to increase the penetrating power and to obtain better cleaning properties.

  Further, as the component (c), an alkylene oxide adduct of alkyl (having 5 to 12 carbon atoms in the alkyl group) phenol can be mentioned, and an alkylene oxide added so that the HLB is also in the above range is preferable. The alkylene oxide is preferably ethylene oxide or propylene oxide, and particularly preferably contains ethylene oxide. The average added mole number of ethylene oxide is preferably 6-15.

  The total content of the component (b) and the component (c) in the steel strip cleaning composition of the present invention parallels the cleaning performance, the viewpoint of reducing the adhesion of the steel strip after annealing, and the stability of the composition. From the viewpoint, in the concentrated composition, it is 0.16 to 18% by weight in the composition, preferably 0.17 to 15% by weight, and more preferably 0.2 to 15% by weight. In the dilute composition, the total content of the component (b) and the component (c) is 0.16 to 1.5% by weight in the composition, preferably 0.2 to 1.2% by weight. %.

  In the steel band cleaning composition of the present invention, the weight ratio (b) / (c) between the component (b) and the component (c) in both the concentrated composition and the diluted composition is: From the viewpoint of reducing the adhesion of the steel strip after batch-type annealing and cleaning properties, it is 100/1 to 100/150, preferably 100/1 to 100/120, more preferably 100 / 1.5 to 100/120. 100 / 1.5 to 100/100 is more preferable, and 100/2 to 100/100 is still more preferable.

[Component (d)]
The composition of the present invention is preferably an aqueous solution because the component (a), the component (b), and the component (c) are stable without causing phase separation, and the aqueous solution has fluidity. It is preferable because the cleaning component can be stably and uniformly supplied to the cleaning tank, and the desired effects of cleaning properties and reduction of the adhesion of the steel strip after annealing are exhibited. In order to obtain an aqueous solution containing the component (a), the component (b), and the component (c), the composition of the present invention contains the following general formulas (d1) to (d) as the component (d) in the concentrated composition. One or more compounds selected from the compounds represented by d2) are contained.

^{_{-X- R 1d (CH 2) m}} COOM 1 (d1)
R ^2d -COOM ² (d2)
[Wherein, R ^1d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 4 to 22 carbon atoms or an aromatic hydrocarbon group having 5 to 18 carbon atoms, and X represents a group> NH, > N (CH ₂ ) _n COOM ¹ or> CHCOOM ¹ R ^2d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 3 to 22 carbon atoms or an aromatic hydrocarbon group having 5 to 18 carbon atoms. M ¹ and M ² each represent a hydrogen atom, an alkali metal, an aliphatic ammonium group having 1 to 4 carbon atoms, an ammonium group or an alkanol ammonium group, and m and n each represent an integer of 1 to 3. ]

  Specific examples of the compound represented by the general formula (d1) [hereinafter referred to as the component (d1)] include those represented by the following formula. Among them, a compound having a 2-ethylhexyl group or a dodecyl group is more preferable, and a compound having a 2-ethylhexyl group is more preferable from the viewpoint of foam suppression.

[Wherein, M ¹ has the same meaning as described above. Note that n means a straight chain. ]

  Examples of the compound represented by the general formula (d2) [hereinafter referred to as component (d2)] are caproic acid, enanthic acid, caprylic acid, capric acid, lauric acid, butyric acid, valeric acid, 2-ethylhexanoic acid, and these And the like.

In the general formulas (d1) to (d2), examples of the alkali metal represented by M ¹ and M ² include potassium and sodium. Examples of amines that can be aliphatic ammonium groups having 1 to 4 carbon atoms include methylamine, ethylamine, propylamine, butylamine, ethylenediamine, and diethylenetriamine. Examples of alkanolamines that can be alkanolammonium groups include monoethanolamine, diethanolamine, and triethanolamine. Examples include ethanolamine and other alkanolamines having 2 to 10 carbon atoms. M ¹ and M ² are preferably a hydrogen atom or an alkali metal.

  The component (d) of the present invention requires the component (d1) from the viewpoint of solubilization of the nonionic surfactant in the aqueous alkali solution, and from the viewpoint of productivity and more stable solubilization, the component (d2) That is, it is preferable to contain the component (d1) and the component (d2) as the component (d). From such a viewpoint, the weight ratio (d1) / (d2) when combining the component (d1) and the component (d2) is preferably 0.1 / 1 to 70/1, and 0.4 / 1 to 50 / 1 is more preferable, and 0.7 / 1 to 30/1 is still more preferable.

  In the present invention, the component (d1) is essential, and the component (d2) is further blended to solubilize the nonionic surfactant as the component (c) in the alkaline aqueous solution with a small amount of use. Can be realized. The solubilization of the nonionic surfactant in the aqueous alkali solution is solubilized by forming a shelf layer micelle by orienting the highly hydrophilic component (d1) to the nonionic surfactant having reduced hydrophilicity. It is estimated that However, since it is presumed that the component (d1) having excellent base resistance is dissolved in a large amount and cannot efficiently contribute to micelle formation, the component (d2) having low solubility in an alkaline aqueous solution is used in combination. By orienting to the component (d1), mixed micelles can be formed efficiently, and the amount of the component (d1) used can be reduced.

  The composition of the present invention composed of an aqueous solution has a composition temperature of 50 ° C. or higher, and particularly those containing component (d) can be stably stored at a low composition temperature (40 to 50 ° C.). It is more preferable because it can reduce the high cleanability and the adhesion of the steel strip after batch annealing.

  In the steel strip cleaning composition of the present invention, the content of the component (d) in the concentrated composition is preferably 0.01 to 20% by weight from the viewpoint of obtaining excellent product stability. 10 to 10% by weight is more preferable, and 0.3 to 5% by weight is still more preferable.

[Cleaning composition for batch-type annealed steel strip]
The steel strip cleaning composition of the present invention contains water such as tap water, ion-exchanged water, and industrial water. An organic water-soluble solvent such as a lower alcohol may be used as long as the effects of the present invention are not impaired. Furthermore, the following components can be contained.

[Component (e)]
The steel strip cleaning composition of the present invention can contain a chelating agent as component (e).

  The chelating agent is considered to play a role of enhancing the cleaning effect by binding to and removing metal atoms in the soil.

  Examples of the chelating agent for component (e) include alkali metal salts or lower amine salts of aldonic acids such as glyceric acid, tetronic acid, pentonic acid, hexonic acid, heptonic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, ethylenediaminediacetic acid, tetra Alkali metal salts or lower amine salts of aminocarboxylic acids such as ethylenetetramine hexaacetic acid, alkali metal salts or lower amine salts of oxycarboxylic acids such as citric acid and malic acid, aminotrimethylenephosphonic acid, hydroxyethylidene diphosphonic acid, ethylenediamine Alkali metal salts or lower amine salts of phosphonic acids such as tetramethylenephosphonic acid and diethylenetriaminepentamethylenephosphonic acid, and alkanolamines such as ethanolamine, diethanolamine and triethanolamine And the like. Among these chelating agents, gluconic acid, glucoheptonic acid, ethylenediaminetetraacetic acid, citric acid, malic acid, hydroxyethylidene diphosphonic acid alkali metal salt or lower amine salt, more preferably sodium gluconate, glucoheptone Sodium acetate, sodium ethylenediaminetetraacetate, sodium citrate, sodium hydroxyethylidene diphosphonate. Two or more chelating agents can be used in combination, and in particular, the use of an alkali metal salt or lower amine salt of an aminocarboxylic acid and an alkali metal salt or lower amine salt of an oxycarboxylic acid provides a low-temperature detergency. To preferred.

  In the steel strip cleaning composition of the present invention, the content of the component (e) is preferably 0.01 to 30% by weight in the concentrated composition from the viewpoint of improving the cleaning property, and 0.05 to 10%. % By weight is more preferred, and 0.1 to 5% by weight is even more preferred. In addition, the content of the component (e) is preferably 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight, and 0.1 to 0.4% by weight in the diluted composition. Further preferred.

[Optional ingredients]
The steel strip cleaning composition of the present invention can contain an alkali agent other than the component (a) as required, for example, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, Examples thereof include phosphates such as trisodium phosphate, carbonates such as disodium carbonate, sodium hydrogencarbonate and dipotassium carbonate, and borate salts such as sodium borate. Two or more alkali agents may be combined. Sodium hydroxide and potassium hydroxide are preferable, and sodium hydroxide is more preferable.

  The steel strip cleaning composition of the present invention contains each component at the concentration as described above, that is, each component of the stock solution is in the above range. The composition of the present invention is used as it is or as a composition diluted with water or the like, but the concentration of component (a) in the composition (steel strip cleaning composition) at the time of use is determined by batch annealing. From the viewpoint of reducing the degree of adhesion of the steel strip later, 0.3 to 4.5% by weight is preferable, 0.5 to 3.0% by weight is more preferable, and 1.0 to 3.0% by weight is even more preferable. In addition, the concentration of the component (b) in the composition (stock solution or diluted solution) at the time of use is preferably 0.15 to 2.0% by weight from the viewpoint of reducing the adhesion of the steel strip after batch annealing. 0.17 to 1.5 weight% is more preferable, and 0.2 to 1.0 weight% is still more preferable. What is necessary is just to adjust the density | concentration of a component (c) with the density | concentration of a component (b). In addition, the concentration of the component (e) in the composition (stock solution or diluted solution) at the time of use is preferably 0.01 to 1% by weight, and 0.03 to 0.5% by weight from the viewpoint of improving detergency. Is more preferable, and 0.05 to 0.3% by weight is still more preferable. A composition having a concentration of each component in this range, particularly a dilute composition, can be used as it is. In addition, a diluted composition can also be diluted and used as needed.

  Among the detergent compositions for steel strips of the present invention, the concentrated composition is a one-component type containing component (a), component (b), component (c), component (d), and other components. It is preferable that it consists of an aqueous solution containing the composition, especially component (a), component (b), component (c) and component (d), and other components. Among the steel strip cleaning compositions of the present invention, the dilute composition is a one-component composition containing components (a), (b) and (c), and other components. In particular, it is preferably composed of an aqueous solution containing the component (a), the component (b) and the component (c), and further other components.

  The steel strip cleaning composition of the present invention is preferably in the state of an aqueous solution at least at 40 ° C., and further at 40 to 50 ° C., from the viewpoint of achieving both improved cleaning properties and reduced adhesion of the steel strip. The steel strip cleaning composition of the present invention can be produced by mixing each component at a temperature of 50 ° C. or higher and stored at 50 ° C. or higher. For the concentrated composition, in the presence of component (d), the total amount of component (a), component (b) and component (c) is preferably 35% by weight or less, more preferably 32% by weight or less, More preferably, it can be obtained as a composition in an aqueous solution at 40 to 50 ° C. by mixing each component at 25% by weight or less. Here, an aqueous solution is a solution using water as a solvent, and a solution is a solution in which one or more solutes are dissolved in another substance and is in a uniform liquid state, like a suspension. It does not include those in which colloidal particles are dispersed in a solvent.

  Of the cleaning composition for steel strips of the present invention, the concentrated composition is prepared by diluting one prepared as a concentrated product as described above, and mixing each component with water before use. It can also be used as a composition containing each component at a concentration suitable for use. That is, the component (a) [including an alkaline agent other than the component (a)] and other components [preferably a composition containing all components other than the component (a)] are separately added to water at the time of use. Can be used as a cleaning solution containing each component at a predetermined concentration. For example, component (a) and other components are stored in separate storage tanks, and each component is supplied to the cleaning tank from each tank. They can be diluted with water to a concentration suitable for use to form a cleaning solution.

[Method of manufacturing steel strip]
A preferred method for producing a steel strip using the steel strip cleaning composition of the present invention will be described.

  Usually, the steel strip is manufactured through processes such as a cold rolling process, a cleaning process, a batch annealing process, a plating process, and a chemical conversion treatment process. Among these, the cleaning process generally includes a process of preliminary cleaning (immersion cleaning / spray cleaning) → electrolytic cleaning → brush cleaning → rinsing. As a method for adding the steel strip cleaning composition in the cleaning process, in the case of a one-component cleaning agent, water and a stock solution (one-component cleaning agent) are added to a cleaning tank and mixed and diluted. In the case of a one-component cleaning agent, the concentration management is controlled by the alkali concentration [concentration of alkali agent other than component (a) and component (a)]. In addition, when each component is separately added to the washing tank and used, it is preferable to use an aqueous solution of an alkaline agent such as component (a) and a composition containing all of the remaining components. The composition containing all of the remaining components and the concentration of the alkaline agent such as) is controlled mainly by the specific nonionic surfactant concentration that is component (c). Washing is conventionally performed in a temperature range of 60 to 90 ° C, and recently, it is increasing at 40 to 60 ° C. The cleaning composition for batch-type annealed steel strips of the present invention has good cleanability and adhesion reduction effect not only at a high temperature of 60 to 90 ° C. but also at a temperature of 40 to 60 ° C., and even at a low temperature of 40 to 50 ° C. is there. In the case of a general cleaning line, the cleaning time is 0.5-5 seconds for immersion cleaning, 0.5-5 seconds for spray cleaning, 0.5-5 seconds for electrolytic cleaning, 0.5-5 seconds for brush cleaning, and rinse 0. .5 to 5 seconds. The steel strip cleaning composition of the present invention can also be used in such a normal cleaning process.

  The annealing process is performed by an annealing method somewhat different depending on the purpose. Generally, this is called complete annealing. The steel strip is put in an annealing furnace, heated to 800 ° C. to 900 ° C. and held for a certain period of time until about 400 ° C. After cooling slowly in the furnace, pull it out and air-cool.

  When the surface of a cold-rolled steel strip becomes smoother, that is, the roughness of the surface of the steel strip decreases, for example, when the roughness (Ra) is 0.1 to 0.6 μm, the steel is more likely to be annealed at a high temperature. The band surface is very easy to weld (adhesion = seizure). When annealing cold-rolled steel strips at high temperatures in batch mode, if silicon is electrodeposited on the steel strip surface by electrolytic cleaning of the steel strip in a silicate solution before annealing, the contact area between the steel strips is reduced. Therefore, it is considered that welding (adhesion = burn-in) can be prevented. The steel strip cleaning composition of the present invention is obtained by adding two specific surfactants to silicate under specific conditions, so that even a steel strip having a low roughness can be adhered to the steel strip by electrodeposition silicon. The reduction effect can be greatly improved.

  The steel strip cleaning composition and the steel strip manufacturing method of the present invention are particularly preferably used in batch coil annealing of tight coils.

[I] Preparation of concentrated composition (I-1) Examples 1 to 17 and Comparative Examples 1 to 9 and 11
The components (e) in Tables 1 to 3 are dissolved in water at room temperature (25 ° C.). Next, component (b), component (c) and component (d) in Table 1 are added at room temperature, and mixed (stirred) and dissolved. Further, component (a) in a state dissolved at 50 to 80 ° C. (without crystal precipitation) [Sodium orthosilicate; 30% solid content aqueous solution, Nippon Chemical Industry Co., Ltd. product, or No. 2 sodium silicate; 40 % Aqueous solution, product of Asahi Glass S-Tech Co., Ltd.] or sodium hydroxide was added and mixed (stirred) to prepare a transparent one-part type steel band cleaning composition. However, Comparative Examples 5a, 5b, 7, and 11 were in a state of being separated into two layers after being stirred and allowed to stand.

(I-2) Comparative Example 10
An aqueous solution (40% solid content) of sodium polyacrylate was mixed with water in which the component (e) in Table 3 was dissolved and stirred, and then water was added so that the concentration in the composition would be 40% by weight. Mix sodium oxide to make a suspension containing component (b), sodium polyacrylate, and sodium hydroxide, and then stir and mix component (c) using a homogenizer (rotation speed 12000 rpm) while applying shear. Thus, a slurry-like one-part type steel strip cleaning composition was prepared.

[II] Preparation of Dilute Composition (Examples 18 to 25 and Comparative Example 12)
The steel strip cleaning composition shown in Table 4 was prepared in the same manner as (I-1) above (however, the component (d) was not added). In Comparative Example 12, since the amount of sodium silicate is large, it is in a state where two layers are separated immediately after production, after stirring and standing, and even after storage under the same conditions as the evaluation of storage stability described later. The separation state did not disappear.

[III] Evaluation of Detergency (Degreasing) and Adhesion (III-1) Preparation of Evaluation Sample 1000 g of the steel strip cleaning composition (concentrated composition) shown in Tables 1 to 3 was placed in a polyethylene container, 40 After storage at 2 ° C. for 2 months, 20 g of the lower layer of the composition is sampled from the lower part of the container, a required amount is sampled from it, diluted to a predetermined concentration with water, and the steel strip cleaning test ( Degreasing) and adhesion test. Comparative Example 5a and Comparative Example 5b have the same composition, but Comparative Example 5a was subjected to this evaluation immediately after the preparation in (I-1) above, and was stirred until immediately before the evaluation. And uniform system was used. Further, in Comparative Example 11, solidification occurred after storage, and thus the cleaning property and adhesion degree could not be evaluated.

  Moreover, about the washing | cleaning agent composition for steel strips (dilute system composition) of Table 4, the washing | cleaning test (degreasing property) and adhesiveness test of a steel strip by the following method, without performing the preservation | save and dilution in (II-1). Went. Note that Comparative Example 12 was used with stirring until just before the evaluation.

(III-2) Steel strip for test After rolling, two types of rolled steel sheets having different roughness before washing were cut out to have a width of 1 m × length (rolling direction) of 0.5 m. Further, from each rolled steel sheet, a steel strip having a width of 25 mm and a length of 50 mm for measuring the roughness measurement, the average oil adhesion amount, the cleaning property and the adhesion degree was cut out.

(III-2-1) Measurement of roughness The steel strip for roughness measurement was immersed in hexane, the surface was wiped with a tissue paper, and was naturally dried. About the length direction of three substantially equal places in the width direction of this steel strip, the roughness (Ra) was measured using the surface roughness shape measuring machine SURCOM 110A, and the average value was cut out of this steel strip. The roughness of the rolled steel sheet was used. The roughness of the two types of rolled steel sheets was 0.2 μm and 0.5 μm, respectively.

(III-2-2) Average oil adhesion amount About five steel strips for measuring the average oil adhesion amount, the oil adhesion amount was measured using a metal plate adhesion oil amount measuring device (EMIA-111 / manufactured by Horiba, Ltd.). The average value of the five oil adhesion amounts was defined as the average oil adhesion amount of the rolled steel sheet from which the steel strip was cut. The average oil adhesion amount of the two types of rolled steel sheets was 140 mg / m ² .

(III-3) Evaluation of Detergency (1) Cleaning Test Procedure A cleaning solution comprising the cleaning compositions for steel strips shown in Tables 1 to 3 diluted at the dilution ratios shown in Tables 1 to 3 and a cleaning solution comprising the cleaning composition shown in Table 4 (Hereinafter collectively referred to as a test cleaning solution), a steel strip for cleaning test is immersed in a test cleaning solution at 80 ° C. or 40 ° C. for 1 second, and then the steel charged position is negative at a current density of 5 A / dm ^2. It was switched over once every 0.5 seconds exactly, electrolyzed, then rinsed with water and dried.

(2) Measuring method of residual oil adhesion amount The detergency was evaluated by the residual oil adhesion amount on the surface of the steel strip after the cleaning test. The amount of oil remaining on the surface of the steel strip was all measured using a metal plate attached oil amount measuring device (EMIA-111 / Horiba Seisakusho). The measured value is an average value of five steel strips. Detergency is an evaluation of degreasing properties, and the criterion is that the amount of residual adhered oil is 10 mg / m ² or more is poor (x), 3 mg / m ² or more and less than 10 mg / m ² is good (◯), 3 mg / m Less than ² was considered excellent (優).

(III-4) Evaluation of adhesion The same steel strip used for cleaning was cut into a size of 20 mm x 50 mm (hereinafter referred to as a steel strip). The steel strip was subjected to electrolytic cleaning based on the cleaning test procedure performed in the evaluation of cleaning performance. The amount of electrodeposited Si on the steel strip after electrolytic cleaning and the peel strength of the steel strip were measured.

(1) Electrodeposition amount of Si measured fluorescent X-ray analyzer (ZSX 100e, Rigaku), the intensity of Si of the steel strip after cleaning was measured, the steel strips 1 m ² per using a pre-prepared calibration curve The amount of Si adhered was determined. From the viewpoint of ensuring the plating characteristics of an effective reduction and post-process the degree of adhesion, Si deposition amount is preferably ^{1~5mg / m 2, 2~4mg / m} 2 is more preferable.

(2) Measurement of peel strength Insert a spacer for each pair of steel strips after washing so that they overlap each other by 20mm x 30mm, and set them on the holder as shown in Fig. 1. The surface pressure P is 50kg / cm ² in the stack. After pressurizing to become, it was charged in an annealing furnace and annealed. After completion of annealing (after completion of cooling), as shown in FIG. 2, the upper and lower steel strips were pulled in opposite directions, and the peel strength T was measured. The peel strength was measured at a tensile speed of 50 mm / min using an autograph AGS-500G (Shimadzu Corporation) as a measuring device. The annealing conditions are as follows.
<Annealing conditions>
Annealing atmosphere: N ₂ gas + H ₂ gas (H ₂ gas: 5% by volume)
Annealing temperature: 700 ° C
Temperature rising time: 2 hours Annealing time: 1 hour Cooling time: 10 hours The adhesion strength was evaluated according to the following criteria based on the peel strength T value.
◎: Peel strength is 10 kg / cm ² or less ○: Peel strength is more than 10 kg / cm ² , 20 kg / cm ² or less △: Peel strength is more than 20 kg / cm ² , 30 kg / cm ² or less ×: Peel strength is 30 kg / cm ^More than ²

[IV] Evaluation of Storage Stability 1000 g of the steel strip cleaning composition (composition before dilution) shown in Tables 1 to 3 was placed in a polyethylene container and stored at 40 ° C. for 2 months. Observed. “None” indicates no change in appearance and no phase separation, and “Yes” indicates that phase separation occurs. Further, “None” indicates that neither thickening nor solidification occurs, and “Yes” indicates that thickening and / or solidification occurs.

The components in the table mean the following (hereinafter, EO is ethylene oxide, PO is propylene oxide, and mol is an average number).
• Lauryldimethylaminoacetic acid betaine: a compound in which R ¹ in the general formula (b1) is a lauryl group (alkyl group having 12 carbon atoms) and R ² and R ³ are both methyl groups • Trimethylglycine: in the general formula (b1) R ^1, R ^2, compounds of R ³ are both methyl groups glycine: R ¹ in the general formula (b1), R ^2, compounds of R ³ are both hydrogen atoms, 2-lauryl -N- carboxymethyl -N- Hydroxyethyl-imidazolinium betaine: a compound in which R ⁴ in the general formula (b2) is a lauryl group (alkyl group having 12 carbon atoms) lauryldimethylamine oxide: R ⁵ in the general formula (b3) is a lauryl group (carbon C-12: secondary dodecanol EO 12 mol PO3 mol block adduct c-2: EO4 mol adduct of 2-ethylhexanol c-3: decanol E 8 moles PO4 mole block adduct · c-4: 2 Grade dodecanol EO5 mol PO2 mol EO5 mole block adduct

In an Example and a comparative example, it is the schematic which shows the installation condition of the steel strip piece when annealing. It is the schematic which shows the direction which measures the peeling strength of the steel strip after annealing in an Example and a comparative example.

Claims (5)

Silicate (a) 0.1 to 26% by weight, one or more amphoteric surfactants (b) selected from compounds represented by the following general formulas (b1) to (b3) 0.15 to 15% by weight [below , Component (b)], one or more nonionic surfactants (c) selected from alkylene oxide adducts of alcohols having 4 to 24 carbon atoms (hereinafter referred to as component (c)), the following general formula (d1) A cleaning composition for batch-type annealed steel strips containing at least one compound (d) selected from the compounds represented by (d2) and water, the sum of component (b) and component (c) Washing for a batch-type annealed steel strip having a content of 0.16 to 18% by weight and a weight ratio (b) / (c) of the component (b) to the component (c) of 100/1 to 100/150 Agent composition.

(In the formula, R ¹ represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 20 carbon atoms, and R ² and R ³ each represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 3 carbon atoms.)

(In the formula, R ⁴ represents an alkyl group or an alkenyl group having 1 to 30 carbon atoms.)

(In the formula, R ⁵ represents an alkyl group or alkenyl group having 1 to 20 carbon atoms.)
_{^{-X- R 1d (CH 2) m}} COOM 1 (d1)
R ^2d -COOM ² (d2)
[Wherein, R ^1d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 4 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and X represents a group> NH, > N (CH ₂ ) _n COOM ¹ or> CHCOOM ¹ R ^2d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 3 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. M ¹ and M ² each represent a hydrogen atom, an alkali metal, an aliphatic ammonium group having 1 to 4 carbon atoms, an ammonium group or an alkanol ammonium group, and m and n each represent an integer of 1 to 3. ] Silicate (a) 0.1-4.5% by weight, one or more amphoteric surfactants (b) 0.15-1.3 selected from compounds represented by the following general formulas (b1)-(b3) % By weight [hereinafter referred to as component (b)], one or more nonionic surfactants selected from alkylene oxide adducts of alcohols having 4 to 24 carbon atoms (hereinafter referred to as component (c)), and water A cleaning composition for batch-type annealed steel strips containing 0.1 to 1.5% by weight of the total content of component (b) and component (c), and component (b) and component A cleaning composition for a batch-type annealed steel strip, wherein the weight ratio (b) / (c) of (c) is 100/1 to 100/150.

(In the formula, R ¹ represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 20 carbon atoms, and R ² and R ³ each represents a hydrogen atom or an alkyl group or alkenyl group having 1 to 3 carbon atoms.)

(In the formula, R ⁴ represents an alkyl group or an alkenyl group having 1 to 30 carbon atoms.)

(In the formula, R ⁵ represents an alkyl group or alkenyl group having 1 to 20 carbon atoms.)
_{^{-X- R 1d (CH 2) m}} COOM 1 (d1)
R ^2d -COOM ² (d2)
[Wherein, R ^1d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 4 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms, and X represents a group> NH, > N (CH ₂ ) _n COOM ¹ or> CHCOOM ¹ R ^2d represents a saturated or unsaturated linear or branched aliphatic hydrocarbon group having 3 to 22 carbon atoms or an aromatic hydrocarbon group having 6 to 18 carbon atoms. M ¹ and M ² each represent a hydrogen atom, an alkali metal, an aliphatic ammonium group having 1 to 4 carbon atoms, an ammonium group or an alkanol ammonium group, and m and n each represent an integer of 1 to 3. ]   The cleaning composition for a batch-type annealed steel strip according to claim 1 or 2, wherein the silicate (a) is No. 2 silicate.   Furthermore, the cleaning composition for batch type annealed steel strips according to any one of claims 1 to 3, further comprising a chelating agent (e).   The steel strip manufacturing method which has the electrolytic cleaning process using the cleaning composition for batch type annealing steel strips in any one of Claims 1-4, and the batch type annealing process performed after the said electrolytic cleaning process.

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