JPS61243120A - Production of steel foil having excellent workability and adhesiveness - Google Patents

Abstract

PURPOSE:To make possible the production of steel foil having excellent workability, corrosion resistance and adhesiveness by subjecting the surface of the steel foil produced by cold rolling to a degreasing treatment and a treatment for forming a film for preventing seizure in the stage of annealing then coiling the foil and subjecting the coiled foil to bright annealing and further to a temper treatment by liquid honing and a treatment for forming a chemical conversion treatment film. CONSTITUTION:A low carbon steel slab is rolled to the steel foil having 10-100mum thickness by hot rolling, pickling, cold rolling and continuous annealing and the surface thereof is cleaned by degreasing at the same time the film for preventing seizure in the stage of annealing consisting essentially of a metallic oxide, metallic phosphorus compd. and metallic phosphate compd. is formed thereon. Such foil is coiled and is subjected to the bright annealing by box annealing at 600-660 deg.C, then to the liquid honing using an aq. liquid contg. an abrasive material and chemical conversion treatment agent, by which the coil is temper-treated. The chemical conversion treatment film is thereafter formed on the surface by using the liquid honing or executing an electrolytic treatment. The steel foil having the workability and corrosion resistance as well as the excellent adhesiveness to various plastic films, paints and adhesive agents is thus obtd.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention provides workability or workability as well as corrosion resistance and
The present invention also relates to a method for producing steel foil that has excellent adhesion to various plastic films, paints, adhesives, etc.

(Prior Art) Recently, there has been a movement to apply steel foil to various packaging materials, containers, electrical appliances, etc., but there is still no satisfactory product in terms of performance or price. Clearly, improvements are desired.

Currently, the manufacturing method for steel foil is (a) Method by cold rolling.

(b) Method using electric iron plating (electrolytic method).

(c) A method in which molten steel is poured onto the roll surface and rapidly cooled to form a steel foil (rapid cooling method).

etc. have been put into practical use, but each has advantages and disadvantages, and there are many points that need improvement in terms of productivity, product performance, price, etc.

(The opening point to be solved by the invention) The cold rolling method is a method in which cold-rolled thin sheets, which are currently produced in large quantities, are further cold-rolled into foil.
(Processing 2) It is described on page 639, published by Maruzen on September 30, 1972. It is possible to use the current production equipment for cold-rolled thin sheets, and it is possible to produce steel foil with a wide width and excellent surface condition and shape. It also has excellent productivity. However, because the steel foil is subjected to large cold reduction, the crystal grains are fibrous, the mechanical properties are highly directional, and although it has high strength, it has significantly poor workability. In order to improve these defects, it is necessary to perform annealing and recrystallization. However, when a thin material like steel foil is annealed in a coiled form, a large amount of pressure is applied between the surfaces of the steel foil, resulting in heat-pressure bonding, so-called seizure, and it becomes impossible to unwind one coil after annealing. Disappearance often occurs. As an annealing method, a continuous annealing method is also widely and commonly used in the production of cold-rolled thin sheets, but with existing equipment, when annealing something as thin as a steel foil, it is easy to cause a narrowing bt in the furnace. This often results in plate breakage, resulting in significantly lower productivity. For this reason, coil annealing, that is, box annealing is preferable for annealing, but in this case, as described above, measures to prevent seizure are required.

Furthermore, the shape of the steel foil after annealing is deteriorated, and when processed, sharp folds called stretcher strains or folds occur, which deteriorates the appearance.

In order to correct these defects of annealed sheets, current cold-rolled thin steel sheets undergo light reduction (generally a reduction rate of 0.
5 to 2 qb), but in the case of steel foil, when skin pass rolling is performed, since the plate thickness is thin, it is easy to draw and break the plate, and the productivity is extremely poor. For this reason, a thermal refining method is desired as an alternative to the rolling method.

In addition, steel foil is rarely used as it is, and is often used by laminating it with other materials, so it has poor corrosion resistance.
It is desirable that it has excellent paintability, adhesion to various types of glass sticks, paper, etc.

For this purpose, it is necessary to apply some kind of surface treatment film. Currently, surface-treated steel sheets that are used in large quantities for containers include tinplate, TF8-CT (two-layer plating of lower layer chromium and upper layer fermented chromium), and nickel-plated steel sheets, which are manufactured in their respective manufacturing facilities. ing. In the case of steel foil, treatment using continuous surface treatment equipment is extremely difficult, as the sheet thickness is thin, resulting in deterioration of shape, or frequent occurrence of drawing, sheet breakage, etc., and productivity is extremely low. In particular, it is more difficult to obtain annealed products because they are softened. Therefore, new b
Development of surface treatment methods is desired.

In the electrolytic method, divalent iron ions (F
In this method, iron is precipitated by electrolysis from an iron plating bath containing e), and the iron coating deposited on the roll surface is continuously peeled off from the roll surface to obtain steel foil. According to this method, it is possible to obtain a steel foil that is relatively wide, has no directionality in mechanical properties, and has relatively good workability as it is cold-rolled. However, since the rate of forming the foil is determined by the amount of electricity electrolyzed, productivity is extremely poor. For example, even if electrolysis is carried out at a high current density of 200 A7 dm2 and the deposition efficiency is io, it will take about 68 μm to obtain a 50μ steel foil.
It takes a long time of seconds. In addition, the electrolyte contains F.
Although an acidic bath containing F,2+ is easily oxidized to Fe3+, as Fe3+ increases, the electrodeposition efficiency and uniformity of electrodeposition decrease, and good electrodeposition cannot be obtained, so the bath composition must be controlled. Very important. For this plating bath management,
Equipment for reducing F@ to Fe2+, equipment for filtering precipitates, etc. are required.

There are many points that are difficult to implement in mass production.

Furthermore, steel foil obtained by electrolysis has the disadvantage that since iron is electrolytically deposited on the roll surface, there is a significant difference in surface quality between the front and back surfaces. That is.

The roll surface side inherits the shape of the roll surface as it is, whereas the electrolyte side has a rough satin-like surface shape. This is because the crystals of the electrodeposited material grow as the electrodeposition progresses.
As the thickness increases, the surface becomes rougher and the difference between the front and back becomes larger. Although this is not necessarily a drawback, the electrodeposited surface is generally too rough, which is undesirable from the viewpoint of corrosion resistance. It is also undesirable that the roughness cannot be adjusted arbitrarily. Furthermore, in the end,
Although it is desirable to perform surface treatment, it is difficult to apply current surface treatment methods even in the case of electrolytically processed steel foil.

The rapid cooling method is a method in which molten metal is made to flow down through a slit nozzle onto the surface of a cooling roll, and the solidified metal foil is continuously wound onto the roll. This method has been put to practical use in the production of amorphous foils such as electromagnetic steel, but its use is extremely limited and it is hardly used for containers and the like. However, amorphous electrical steel foil is used for electrical equipment because of its excellent electrical properties. Also, in the steel foil of
Surface treatment is desired, but as mentioned above, treatment is difficult with current surface treatment equipment, and the development of new treatment methods is desired.

As described above, the cold rolling method is the most suitable method for manufacturing steel foil that has excellent performance for general use, especially for containers or other packaging materials, and can be mass-produced. Therefore, in order to provide K with excellent performance, it is necessary to develop a material modification method and a new continuous surface treatment method in place of annealing and temper rolling.

The object of the present invention is to solve the above-mentioned problems when producing steel foil by cold rolling, and to improve workability. Another object of the present invention is to provide a method for manufacturing steel foil with excellent workability, corrosion resistance, and adhesion.

(Means and effects for solving the problems) From this viewpoint, the present inventors studied a method for producing steel foil by cold rolling, and arrived at the present invention.

That is, first, we investigated methods for preventing seizure when box annealing steel foil that has been cold-rolled to the required thickness in a coiled form, and applied various coating treatments, especially chemical conversion coatings, to prevent seizure. I found something that can be prevented.

Seizing during coil annealing is thought to be mainly caused by diffusion at the contact surface between the steel plate surfaces, and is greatly influenced by the coil winding strength, that is, the contact pressure between the steel plate surfaces, the annealing temperature, and time. Even when annealing a thin steel plate with a thickness of around 0.2n, seizure may occur depending on the annealing conditions.
The winding strength of the coil is made loose to the extent that the coil does not lose its shape during handling and annealing, and the annealing temperature is 660°C or less, and the annealing time is 8 hours or less, generally 600 to 630°C.

Annealed in 2-4 hours. Even if annealed under these conditions,
Extremely slight seizure occurs, but most of the products that are normally box annealed have a thickness of 042f1 or more and are thicker than steel foil, so there is almost no problem when unwinding them in the next workpiece after annealing. do not have. However, in the case of steel foil with a thickness of 100 μm or less,
Even if the seizure was mild, which would not have been a problem in the past, sharp creases occurred at the border of peeling when unwinding.

If wrinkles occur or if there are localized unevenness in seizing, the foil may tear from the areas where the seizing is strong, resulting in an unfinished product. Therefore, in order to obtain a steel foil with good workability, one of the important issues is to prevent seizure during annealing.

The present invention provides a method for preventing seizure during annealing by applying
Spreading steel foil comrades? inhibit. It applies a treated film mainly composed of metal oxides, metal phosphorus compounds, and metal phosphate compounds. This treated film may not be visible if the treated films fuse together during annealing, or in some cases the treated film may diffuse into the base steel foil, or the surface of the steel foil after annealing. Performance: corrosion resistance, paintability, various plastic films,
Materials that impair adhesion to adhesives and the like are undesirable except in some applications; rather, materials that improve their performance are desirable. As a result of examining appropriate treatment coatings from this perspective, we found that various phosphoric acids, phosphates, chromic acids, chromates, stannates, aluminates, silicates, titanates, niobate, and tungstates. It has been found that nine coatings, especially chemical conversion coatings, exhibit excellent performance using a treatment bath containing either a single or a composite aqueous solution as the main component. Various of the above-mentioned substances can be used as the main ingredient of the treatment bath, but the price,
From the viewpoint of stability and quality of the treatment bath, phosphoric acid, phosphates, chromic acid, chromates, aluminates, silicates, etc. are preferable, and chemical conversion coatings with sufficient performance can be obtained with these.

As a coating treatment method, it is also possible to apply a neutral salt aqueous solution of the treatment agent.

However, from the viewpoint of ease of film formation, corrosion resistance, properties, etc., oxidizing and acid treatment is preferable.

As the chemical conversion treatment method, various known methods can be used.

For example, in the case of phosphoric acid, various chemical conversion treatment methods for steel described in Fujio Mamiya, ``Chemical Conversion Treatment of Metals'' (September 1973, Riko Shuppansha) can be applied. In addition, electrolytic treatment using direct current or alternating current can be applied in such treatment baths, but direct current anodic electrolytic treatment or alternating current electrolytic treatment, in which steel foil is used as an anode, has problems with film formation speed, stability of the formed film, etc. Excellent in terms of.

There are various phosphate treatment methods such as manganese phosphate, zinc phosphate, zinc-calcium phosphate, and iron phosphate, but in the present invention, iron phosphate treatment provides sufficient performance. It is advantageous to use a treatment bath that performs both alkaline degreasing and chemical conversion treatment, since the degreasing step before the chemical conversion treatment can be omitted.

Therefore, the amount of treatment film required is 0.2~
If the layer size is 21 m2 or less, a sufficient anti-seizure effect cannot be obtained; if the layer is less than 0.21 m2, it is unnecessary; if the layer is 217 m2 or more, it is unnecessary), and in the case of dipping or spray treatment, a long processing time is required. , poor productivity.

A chemical conversion coating using chromic acid or a water-soluble romate aqueous solution is also effective in the present invention. A chemical conversion coating can be obtained by either immersion or electrolytic treatment, but it is difficult to control the composition of the treatment bath, the processing time required to produce the required amount of coating, and the performance of the produced coating. Therefore, electrolytic treatment is preferable.

Cathodic electrolysis treatment in an aqueous solution of chromic acid produces Tln, which is currently produced in large quantities as a surface-treated steel for containers such as canned food.
Free Steal-Chrom@Type (TF
S-CT) is known as a manufacturing method. TFS-C
In order to impart corrosion resistance, T is electrolytically treated in a treatment bath containing anions such as SO4'' or F-, and has a surface coating consisting of two layers of metallic chromium and water-containing chromium oxide. There is. However, in the case of the present invention, a metallic chromium layer is not required, and a water-conserving chromium oxide layer alone is sufficient.

However, the addition of anions such as 5o4F- or F- to the treatment bath tends to have an excellent effect on the formation of a uniform hydrated chromium layer, and control of the coating amount becomes a problem. Therefore, it is possible to form a film of two types, chromium oxide and metal chromium.

As the chromate, various water-soluble alkali metal salts can be used alone, or a mixed aqueous solution of these and chromic acid can be used. As a treatment method, immersion or spray treatment may be used, but cathodic electrolysis treatment is preferable.

In the above chromium-based surface treatment, the required coating amount is 2+wi,v'm or more in terms of the amount of Cr in the coating.

No. 2- or below has no anti-seizure effect ・Chemical conversion treatment in a treatment bath containing aluminates, stannates, etc. as main components can also be carried out by a known method eAluminates, stannic acids As the salt, a water-soluble alkali metal salt can be used and a chemical conversion coating can be formed by anodic electrolysis treatment. In the case of aluminates, an amorphous glue-like aluminum oxide film is formed on the surface of the steel foil by anodic electrolysis treatment, for example in a sodium aluminate-tartrate bath. Therefore, the amount of coating necessary to obtain the effect in the present invention is based on the amount of Az2o in the coating,
It is 40 W/m2 or more. If it is less than 40 w'tn2, a sufficient anti-seizing effect cannot be obtained.

A chemical conversion coating can also be obtained by anodic electrolysis using an alkali metal salt bath of stannic acid, but stannate is expensive and there is no particular reason why stannate should be used.

Furthermore, when the steel foil is electrolytically treated with direct current in an aqueous solution of an alkali metal salt of silicic acid, a 11csio□ film is formed on the surface of the steel foil.
This coating is highly effective in preventing seizure during annealing. In this case, the required coating amount is 2 my/m as KS1 in the coating.
This is the above value, and below this value, the effect is small. This treatment bath has a strong degreasing effect and has the advantage of simultaneously removing cold rolling oil from the surface of the steel foil after cold rolling and applying an anti-seize coating. It also has the disadvantage that S tO is firmly fixed and becomes difficult to remove in the final step of surface treatment, making it difficult to obtain a good surface treatment.

Therefore, conventional surface-treated steel sheets, including tinplate, are TFS.
- In manufacturing CT, we try to minimize the amount of 8102 attached. However, in the present invention, liquid honing is performed instead of temper rolling after annealing, so 5io2
It is easy to remove and can be used as an anti-seize coating.

As mentioned above, it is most desirable to use various chemical conversion coatings as the anti-seize coating in the present invention.
An appropriate chemical conversion coating is selected depending on the type of equipment used for chemical conversion treatment, whether surface treatment is to be performed after annealing, the type of surface treatment, etc.

As the chemical treatment equipment, a continuous electrolytic cleaning line currently used for degreasing cold-rolled thin steel sheets can be used. A suitable treatment bath at this time is a phosphate-based or silicate-based treatment bath that can perform degreasing and chemical conversion treatment at the same time.

In the case of chromate-based and aluminate-based chemical conversion treatments,
Prior to chemical conversion treatment, a degreasing step is required to remove cold rolling oil adhering to the surface of the steel foil. For steel foils with a thickness of 50 μm or more, existing electric tinplate lines and T
It is also possible to use an FS-CT line, a gunde processing line, etc., but as already mentioned, these lines are
A simple, dedicated chemical conversion treatment line with poor workability and productivity and good threadability is desirable.

Steel foil coils with such chemical conversion coatings or applied coatings can be box-annealed at 600 to 660'C for 1 to 8 hours without causing seizure, resulting in a good annealed steel foil. I can do things. However, although annealed steel foil is softened by recrystallization and has significantly improved workability, it reproduces the yield point phenomenon and loses its elasticity. Processability is poor. That is, slight bending at what is generally called a waist bend creates a clear fold line and minute irregularities called stretcher strains around the fold line. Stretcher strain is also caused by tensile processing. In the case of ordinary thin steel sheets, these defects caused by annealing are improved by temper rolling, and the shape of the sheet is also corrected by temper rolling.

Temper rolling has the effect of improving the reduction (reduction) and bulging workability up to a reduction rate of about 21. Therefore, thin steel sheets are always subjected to temper rolling.

However, as already mentioned, it is extremely difficult to subject steel foil to temper rolling using the current temper rolling equipment for thin steel sheets.

The inventors of the present invention have studied various thermal refining methods with good workability and productivity as an alternative to the rolling method, and have found a thermal refining method using liquid honing.

Liquid honing is a method of surface finishing by injecting a liquid uniformly mixed with an abrasive onto the workpiece as a high-speed spray using compressed air, high-pressure water, or centrifugal force from a blade wheel. It is used for surface finishing of products such as resin, glass, and aluminum. When this liquid honing is applied to the surface of a steel plate, the surface layer of the steel plate is hardened by the abrasive that collides with it at high speed, causing work hardening. The abrasive usually used for liquid honing has a particle size of 0. O1~I Il
K is 9 times smaller, and with steel plates of normal thickness, the training effect is limited to the very surface layer. However, the thickness is 100μ
In the case of steel foil with a thickness of less than m, the forging effect extends to the entire thickness. This forging effect is the same as the rolling effect in skin pass rolling, and liquid honing can provide the same effect as when skin pass rolling is applied to annealed steel foil. Furthermore, the shape of the foil is also corrected by honing it under tension. The degree of processing depends on the type of abrasive, such as alumina, silica, iron oxide, mixed melts of these, particles of silicon carbide, glass, various types of glass, etc., the size of the particles, and the injection speed during honing.

It can be easily adjusted by adjusting the spray angle, distance, etc. Moreover, by these means, the shape of the surface of the steel foil, that is, the roughness, roughness shape, appearance, etc., can be arbitrarily changed. Additionally, as already mentioned, it is desirable to apply surface treatment to steel foil to improve its corrosion resistance, paintability, adhesion, etc. This surface treatment can be easily carried out by using a chemical conversion treatment bath as the honing solution. For example, by using an aqueous solution containing various types of phosphorous acid, phosphorous salt, chromic acid, and chromate, or a mixture thereof, an extremely excellent chemical conversion coating can be applied to steel foil at the same time as honing. It can be applied to the surface. When the surface layer of the steel foil is honed to a very thin layer and activated, it is simultaneously exposed to a honing solution, which is also a chemical conversion treatment bath, so that an extremely good chemical conversion coating is formed. or,
In this case, an electrode plate is installed near the honing nozzle, facing the steel foil, so that the honing liquid (including abrasives) that collides with the surface of the steel foil fills and flows between the counter electrode and the steel foil. For example, it is also possible to perform electrochemical conversion treatment. In this case, the counter electrode is placed after the nozzle so that electrolysis can occur after honing. By adding electrolytic treatment, it is easier to control the amount of coating and the properties of the coating, and a wider variety of chemical conversion treatment baths can be used, and as a result, it is possible to apply a wide variety of chemical conversion coatings. Become. For example, by electrolytically treating an aqueous solution of stannate, aluminate, silicate, titanate, niobate, tungstate, etc. with steel foil as an anode, metal acids such as E as the main component can be used. It is possible to form a chemical conversion treatment film. However, in terms of the performance of chemical conversion coatings, such as corrosion resistance, paintability, post-painting corrosion resistance, and adhesion with various adhesives,
Chromic acid is best treated electrolytically using a chromate-based treatment bath.

The polarity in the electrolytic treatment is selected appropriately from the characteristics of the treatment bath and the chemical conversion coating to be formed.

For example, for chromate-based treatment baths, cathodic electrolysis using steel foil as the cathode; for phosphorus salt treatment, anodic electrolysis;
Alternatively, alternating current electrolytic treatment, and in the case of various metal salts such as the above-mentioned aluminic acid, anodization are suitable in terms of film formation rate, performance of the formed film, etc.

In addition, it is necessary to perform chemical conversion treatment at the same time as honing.
It is also possible to use water as the honing liquid and carry out chemical conversion treatment in a separate treatment tank after honing, but as already mentioned, continuous treatment of steel foil becomes extremely difficult as the number of processes increases, so Simple processing equipment is desirable and therefore:
It is more desirable to perform liquid honing and chemical conversion treatment at the same time or consecutively after honing.

In the manner described above, it is possible to obtain a steel foil that is excellent in processability, and has excellent metal resistance, paintability, and adhesiveness.

The manufacturing method of the present invention will be described in detail below.

The steel foil is made from a base plate of low carbon steel, which is currently widely used in the production of tinplate, TFS-CT, etc.

If necessary, it can be made from various types of stainless steel, but it is not common due to cost.

The manufacturing process of the tinplate or TFS-CT 1 plate is as follows. “After temper rolling, the original sheets pass through dedicated continuous surface treatment equipment to become tinplate or TFS-CT.

In forming the steel foil, a second cold rolling is performed in the temper rolling of the manufacturing process (2) of the original sheet.

Make the steel foil to the required thickness. The thickness of the annealed plate at this time is appropriately selected depending on the thickness of the final product, ie, the steel foil, but it is desirable that the rolling reduction ratio be 60 or more, preferably 701 or more. This is because in the subsequent annealing process, the higher the cold rolling reduction, the lower the recrystallization temperature. That is, it is possible to lower the annealing temperature for grains with a high cold rolling reduction rate, which is advantageous in terms of seizure prevention. Furthermore, the recrystallized grain size after annealing becomes larger as the cold reduction wheel is lower, and the workability and strength tend to decrease.

The rolled steel foil is subjected to surface cleaning and anti-seizure treatment prior to annealing. For surface cleaning, an electrolytic cleaning device that is currently commonly used in the production of thin steel sheets can be used.

This electrolytic cleaning equipment is a specialized equipment for removing rolling oil, iron powder, iron soap, and other contaminants that adhere to the surface of steel sheets after cold rolling, and is extremely superior to tinplate or TFS-CT lines. Due to its simple structure, even steel foil can be passed through without any problem.

The detergents used in this electrolytic cleaning device include caustic soda, soda carbonate, sodium metasilicate, sodium orthosilicate, sodium orthophosphate, sodium pyrophosphate, and sodium tripolyphosphate, etc., either singly or in combination of two or more. Used as an aqueous solution. Additionally, an anionic or nonionic surfactant may be added to improve the cleaning effect, or a chelating agent may be added to suppress the function of metal ions in the cleaning solution. Generally, electrolytic cleaning in this cleaning device is performed using a method called a grid pie grid. In other words, several pairs of electrodes are arranged in a skewer shape in the cleaning solution, and the first electrode is connected to the glass side of the DC power supply, the second to the negative side, and so on, with the polarity alternately changed. , the steel plate passes between these electrodes.

Therefore, the polarity of the steel plate between the positive electrodes with respect to the electrodes is negative, and hydrogen is generated from the surface of the steel plate, and similarly, between the negative electrodes, the polarity is positive, oxygen is generated, and a powerful cleaning effect is exerted. be done. In this grid-pie-grid electrolytic cleaning, the cleaning solution includes orthosilicate so/f,
It is known that when used, Pc5io2 precipitates on the surface of the steel plate and exhibits a seizure prevention effect during subsequent annealing. However, this sio2 film adheres firmly to the steel plate during annealing, and subsequent tinplate coatings become difficult to remove during pretreatment in the TFS-CT processing equipment, which adversely affects plating and makes it difficult to remove good tinplate or TFS-CT. Make it difficult to obtain. Therefore, work is generally done to suppress 5IO2 adhesion as much as possible during the cleaning process. Similarly, it is known that when a phosphate-based cleaning solution is used, a phosphate film is formed on the surface of the steel plate. However, the amount thereof is extremely small, and no anti-seizure effect during annealing has been observed.

The anti-seize coating can also be applied to the steel foil of the present invention by electrolytic cleaning. In this case, as for the electrolytic method, it is preferable to use a general electrolytic method in which the steel foil is connected to one pole of the electrolytic power source via a conductive roll, regardless of the grid pie grid method. This is because the chemical conversion film can be formed more efficiently if the polarity of the steel foil is fixed to positive or negative depending on the detergent used. For example, in electrolysis in a detergent containing silicate, 810□ is deposited on the surface of the steel foil either by cathodic electrolysis or anodic electrolysis, but the deposition efficiency is much higher in cathodic electrolysis. On the other hand, in the case of sodium phosphate, almost no film is formed in cathodic electrolytic treatment, and even in a cleaning solution containing b0 sodium aluminate, which requires anodic treatment, no film is formed in cathodic treatment, and At2
A film mainly consisting of 03 is formed.

As described above, the electrolytic cleaning device can clean the surface and apply an anti-seize coating at the same time, but a large amount of cold rolling oil, iron powder, and other contaminants adhere to the surface of the steel foil after cold rolling. Therefore, the rate of deterioration of the cleaning liquid is high, and the target chemical conversion treatment performance is also greatly deteriorated. Therefore, it is preferable that surface cleaning and anti-seize coating treatment (chemical conversion treatment) be performed as separate processes.

By performing the chemical conversion treatment as a separate process, more chemical conversion treatment baths can be used, and the required coating quantity and quality can be controlled. At this time, it is desirable that the chemical conversion treatment equipment be as simple as possible from the viewpoints of sheet threadability and workability, but it is desirable that it be capable of electrolytic treatment. For the purpose of preventing seizure,
Pretreatment for chemical conversion treatment is usually not required, but in preparation for applications that do not require annealing, it is desirable to add pickling equipment to provide a chemical conversion coating with excellent performance. In addition, if chemical conversion treatment to prevent seizure is performed in a separate process, the main ingredients will be chromic acid, various chromates, various types of phosphoric acid, phosphates, aluminates, silicates, stannates, etc. Aqueous solutions can be used as chemical conversion treatment baths. For phosphoric acid and phosphate-based treatments, the desired coating can be applied by a single-liquid immersion process. For tetramic acid and chromate-based treatments, electrolytic treatment using steel foil as the cathode, aluminate, stannate, etc. Then, the steel foil coil, which has been subjected to anodic electrolytic treatment to provide the necessary coating and chemical conversion treatment to prevent seizure, is annealed in a box-contained annealing furnace. The annealing furnace uses various types of tight coil annealing furnaces currently widely used for manufacturing thin steel sheets, and annealing is performed in the same manner as bright annealing of cold rolled steel sheets. The annealing temperature and heating time depend on the steel composition of the steel foil, the cold rolling reduction rate, and the steel foil after annealing! ! ! Although it varies slightly depending on the required mechanical properties etc., it is in the range of 1 to 8 hours at 600 to 660 ° C.
Generally, heating at 620 to 640°C for 1 to 2 hours is sufficient.

From the viewpoint of anti-seizing, the lower the annealing temperature and the shorter the annealing time, the better; however, due to the presence of the anti-seizing film,
Even if annealing is performed at 660°C for 8 hours, no seizure will occur.

After annealing, the steel foil is then passed through continuous liquid honing equipment to hone the surface. Continuous liquid honing equipment enables high-speed processing, enables high productivity, and provides good workability. It is desirable to use dedicated equipment.

Furthermore, as already mentioned, by using various chemical conversion treatment baths in the honing solution, it is possible to simultaneously apply a chemical conversion treatment film with excellent corrosion resistance and paintability to the surface of the steel foil. In addition, in order to obtain an excellent chemical conversion coating in a stable manner, it is desirable to install electric purchasing equipment after honing.
If the electrolytic treatment is a method that uses high-pressure liquid for honing, the chemical conversion treatment bath containing an abrasive agent is sprayed onto the surface of the steel foil and is carried out in such a way that it fills the space between the counter electrode and the counter electrode placed opposite the surface of the steel foil. However, in this case, there is a drawback that the abrasive causes greater wear and tear on the electrode surface. Further, this method cannot be used in the case of honing using high-pressure air because a large amount of air bubbles are present in the electrolytic treatment section. In order to avoid this, by spraying a chemical conversion treatment bath that does not contain an abrasive onto the steel foil, the abrasive is washed away from the surface of the steel foil, and electrolysis is carried out in a treatment bath that does not contain an abrasive. things are desirable. However, in this case, the abrasive content in the processing bath recovered after honing is low, so the abrasive is recovered by filtration.
It is necessary to adjust the liquid to the optimum abrasive content and supply it to the honing nozzle.・Most of the F solution is reused as it is as an electrolytic treatment bath.

The processing equipment can be of either a vertical type (processing is carried out in the section where the steel foil passes vertically) or a structure (processing is carried out in the section where the steel foil passes horizontally). The disadvantage is that the number of changes in the passing direction of the steel foil is large compared to the structure, resulting in poor workability, and it is difficult to prevent the abrasive from getting caught between the lower roll and the steel foil, causing scratches on the steel foil. It has the disadvantage of being extremely difficult to use.Due to this disadvantage, it is desirable to have a vertical or horizontal structure.

By providing the electrolytic treatment section above the honing treatment section, there is an advantage that it is possible to completely and easily prevent the abrasive from entering the electrolytic treatment section, but this advantage is extremely small compared to the above-mentioned disadvantages.

The honing gun used for liquid honing is a commonly used honing gun that sends a mixture of abrasive and honing fluid through a pumper and blows it out through a nozzle using high-pressure air. Any method using a honing liquid may be used.

The number of nozzles required for continuous processing is determined by the width of the steel foil to be processed, the required processing speed, honing work conditions, etc., but in general, when using a circular nozzle, one meter of steel foil in width can be processed. If processing is performed at a speed of 200 m/min, it is sufficient to install 10 to 20 rows in the width direction and two rows in the longitudinal direction facing each other on the front and back sides of the steel foil. If you use a slit nozzle that spans the entire width or a split slit nozzle, you can reduce the number of nozzles, and in the case of simultaneous honing on the front and back sides, it will be easier to balance the jetting force on the front and back sides, but the adjustment of the nozzles will be a little difficult. When processing the front and back surfaces at the same time, which is more difficult and expensive than using a nozzle, it is important to balance the jetting force between the front and back surfaces.If there is large local variation, the shape of the steel foil after processing will deteriorate, and in severe cases, In order to prevent such a situation from resulting in a defective product, one side of the steel foil is brought into contact with a hard substrate such as a roll, the side that does not come in contact with the roll is treated first, and then the other side is treated in the same way. -i It is also possible to take the method of processing, but the equipment is a little complicated. An example of continuous honing equipment with an electrolytic chemical treatment function is shown in Figure 1. The abrasives used for honing are silicon carbide, climatic Alumina, glass, hard glass, iron.

Known particles such as stainless steel are used. When using a chemical conversion treatment bath as the honing solution, use an abrasive that is not affected by the chemical conversion treatment bath.The size of the abrasive particles depends on the desired surface condition of the product, honing work conditions, such as jetting pressure, jetting angle, nozzle size, etc. Appropriate selection is made depending on the spray distance to the steel foil surface, processing speed, etc. An appropriate amount of abrasive is added to the honing liquid in a range of 5 to 60 inches by volume in consideration of workability, and the abrasive is supplied to the nozzle part of the honing gun by a ponder and sent to the jet part. is mixed and sprayed onto the steel foil surface using high-pressure honing fluid or high-pressure air that does not contain The pressure of the honing fluid or air at the inlet of the honing gun is determined by the nozzle diameter.

Although it is adjusted as appropriate depending on the processing speed or the size of the abrasive particles, generally a pressure of 2 kg/lys or more is required.In addition, in continuous honing, the steel foil is subjected to a certain amount of tensile force. In order to undergo honing in the received state, the shape is corrected. As mentioned above, honing solutions that also serve as chemical conversion treatment baths include chromic acid, various chromates, various phosphorous oxygen acids, phosphates, etc. A mixed aqueous solution of one or more of these, an aqueous solution containing sodium aluminate as the main component, etc. are used.Following honing, electrolytic chemical treatment is preferably performed, but at that time, a chromic acid or μm salt-based treatment bath is used. When used, electrolytic treatment using steel foil as a cathode is preferable from the viewpoint of the performance of the chemical conversion coating. Sodium aluminate treatment requires electrolytic treatment using steel foil as a cathode. An even better chemical conversion coating can be obtained by washing with water after the electrolytic treatment and further dipping in lacquered acid.The chemically treated steel foil is washed with water, then dried and rolled up to form a finished product. The steel foil manufactured as described above does not cause stretch dust strain or buckling during processing, has excellent workability, and has a chemical conversion coating that makes it corrosion resistant and easy to paint. It has excellent adhesive properties and has optimal performance as a material for laminated boards and partial laminates laminated with various plastic films, papers, etc.

Depending on the intended use of the finished steel foil, there may be cases where particular resistance to metal or adhesion is not required, and surface treatments such as chemical conversion treatment may be applied at the shipping destination. Honing and tempering are performed using only an abrasive or a solution containing a rust inhibitor, and the product is made into a finished product as it is.

Examples of the present invention will be described below.

(Example) Example 1 A cold-rolled annealed steel plate with a thickness of 0.5 mm was produced by a method that is currently widely used in the steel industry for pre-preparation or TF8 production. In other words, a slab of low carbon steel is processed through the steps of hot rolling, pickling, cold rolling, and continuous annealing to achieve a plate thickness of 0.
．． 51 annealed coils were made.The annealed plates were rolled into a 100μ thick foil using a temper rolling mill commonly used in the steel industry, and then cleaned through a continuous electrolytic cleaning device. After that, a chemical conversion treatment was performed to prevent seizure during box annealing. The chemical conversion treatment conditions are as follows: Chemical conversion treatment bath Aluminic acid So/: 2511/It tartaric acid: 2.
5 till pH: 12.1 Temperature: Room temperature/electrolysis conditions Current density: 5A/da2. Anodic electrolysis treatment time:
1 s@e Chemical conversion treatment was performed continuously under the above conditions, followed by washing with water, drying, winding up 9 times, and annealing. The amount of chemical conversion coating applied is 2
50 "j'/m.The annealing was performed using a Hakoya annealing furnace, which is currently commonly used in the steel industry for coil annealing of thin steel sheets.The annealed steel foil coil was annealed at 1630°C for 1 hour. Next, a continuous liquid horn as shown in Fig. 1,
The material was passed through a polishing machine, and the material was improved by hole-under processing and a chemical conversion coating was applied. In this process, the steel foil showed no seizure and was able to be rewound without any problems.The conditions for liquid honing and chemical conversion treatment were as follows.The abrasive was made of fused alumina. Particle size 37-4
4a approximately spherical particles were used. These alumina particles,
The composition of the honing solution was as follows: 20% by volume was added to the honing solution, and high-pressure air of 6 kll/cm'' was supplied to the honing nozzle using a pump and injected onto the surface of the steel foil.

- Honing liquid composition Aluminic acid salt: 2511/1 Tartaric acid: 2.511/It pH: 12.1 Next, anodic electrolytic chemical conversion treatment was performed in the honing liquid. - The treatment conditions are as follows.

Chemical conversion treatment conditions Treatment bath temperature: room temperature Current density: IQA/dfn2 treatment time: 0
．． 51@1! After the chemical conversion treatment, it was washed with water, dried and rolled up to form a finished product.

Example 2゜In the same manner as in Example 1, an annealed steel sheet coil with a plate thickness of 0.3μ was cold rolled into a foil with a thickness of 50μ, and in the same manner as in Example 1, a chemical conversion treatment was applied to prevent seizure. , annealed. Next, the continuous liquid honing device used in Example 1 was applied to the real male side 1.
processed in the same way. However, the following honing liquid was used.

Honing liquid CrO3: 801/I H, SO2: 0.8 # Bath temperature: 60°C After honing, cathode electrolytic chemical conversion treatment was performed using a honing liquid. The chemical conversion treatment conditions were as follows: Treatment bath temperature: 260°C Current density: 60 A/dm2 Treatment time: 1 field·C After treatment, the product was washed with water, dried, and rolled up to give a finished product.

Example 3゜An annealed steel sheet coil with a thickness of 0.2 - that was cold-rolled in the same manner as in Example 1 was cold-rolled into a foil with a thickness of 30β in a Sendzimer rolling machine.Then, it was heated in a continuous electrolytic cleaning equipment. , a steel foil was used as a cathode in a bath in which trivalent sodium orthosilicate was neutralized with carbon dioxide at 90°C to -t-11, and a current density of 10 A/dm2 was applied.
Electrolytic degreasing was performed for 4 s@e.

With this electrolytic degreasing, the surface of the steel foil has a 10%
Two coatings were formed simultaneously. Film adhesion amount is 80 in Sl.
h-z at 1 Rg/m.

Next, the material was annealed in the same manner as in Example 1, and liquid honing was performed continuously using the apparatus shown in FIG. The annealed steel plate in this treatment was successfully unwound without seizure. The honing agent used was spherical glass with a diameter of 35 to 501I, and the honing liquid was a commercially available phosphate chemical treatment agent for steel, which was mixed according to its specifications.The abrasive had a capacity of 20 inches. Add to honing fluid and send to honing gun with sludge 4, 511/css
In the electrolytic treatment process shown in Figure 1 of Figure 90, high-pressure air was injected onto the surface of the steel foil in step 2, and only the honing solution was filled without electrolysis, allowing the chemical conversion treatment to continue. The time the steel foil is in contact with the honing fluid is 2,51@1! It was.

The steel foil with the completed round ring was washed with water, dried, and rolled up into a finished product.

Example 4 A steel foil with a thickness of 50 μm was rolled in the same manner as in Example 1, and a degreasing agent commonly used in continuous electrolytic cleaning equipment was added to a commercially available degreasing and ferric phosphate chemical conversion treatment agent for steel. Instead, chemical conversion treatment was performed at 70°C simultaneously with degreasing.

In this degreasing and chemical conversion treatment, no electrolysis was performed, and the treatment bath was subjected to a sewage treatment. The annealing after treatment was performed in the same manner as in Example 1. After annealing, liquid honing and electrochemical conversion treatment were performed in the same manner as in Example 2 to obtain a finished product. However, the following honing liquid was used.

Honing liquid Na2Cr2O7.2H20: 301/IPH:4.
5 Temperature: 70°C Example 5 A 100 μm steel foil rolled in the same manner as in Example 1 was degreased by electrolytic cleaning and subsequently treated with chromic acid to provide an anti-seizure coating. The chromic acid treatment was carried out by adding a simple electrolytic treatment device to the current continuous electrolytic cleaning device. The conditions for the chromic acid treatment are as follows.

Processing bath Crys: 40 J'/I H2804: 0.11171! Temperature: 40°C Electrolytic conditions Current density: 30 A/dm" Processing time: Q. After chromic acid treatment for 5 seconds, annealing was performed in the same manner as in Example 1, and then liquid honing and electrolysis were performed under the same conditions as in Example 2. 90 Example 6 A steel foil cold-rolled to a thickness of 80μ in the same manner as in Example 1 was treated with chromic acid to produce a finished product, and was degreased using a continuous one-tile cleaning device and coated with an aqueous ammonium phosphate solution. After degreasing and washing with water, ammonium phosphate was applied by using a roll to squeeze out the ammonium phosphate aqueous solution adhering to the surface of the steel foil using a simple dip coating device, and then drying as it was. Annealing was carried out in the same manner as in Example 1, and then In the same manner as in Example 3, liquid honing was performed to obtain a finished product.

Comparative Example 1 A steel foil cold-rolled to a thickness of 100 aK in the same manner as in Example 1 was electrolytically cleaned and box annealed. This annealed foil 'r:m quality rolled'I
When I tried to use k11FA, my back broke due to seizure.

Breakage occurred frequently, and a good product could not be obtained.

Comparative Example 2゜The cold-rolled steel foil with a thickness of 100 IIm used in Comparative Example 1 was left unannealed and used in the current pT, ', T: Xa -C? Processed in L' manufacturing equipment. Comparative Example 3: As in Example 3, steel foil cold-rolled with a Sendzimer rolling mill to a KS thickness of 3014 was coated without any major problems. Chromic acid treatment was attempted using TFS-CT manufacturing equipment, but the treatment was impossible due to frequent fractures.Therefore, chromic acid treatment was performed using the same method as liquid honing in Example 2.

Comparative Example 4 The cold-rolled steel foil with a thickness of 80μ used in Example 6 was left unannealed. Processed in 'I'FS-CT manufacturing equipment. At normal processing speeds, the plate could not be passed, productivity decreased to less than 1 hour, and it was difficult to adjust the amount of chromate coating, but the process was possible.

Comparative Example 5: An attempt was made to process the 50μ thick cold-rolled steel foil (unannealed) used in Example 4 using TFS-CT manufacturing equipment.
Since it was impossible to treat due to frequent squeezing and breakage, it was treated with chromic acid in the same manner as in Example 2. Degreasing using the continuous electrolytic cleaning device was possible, although the processing speed decreased to 14 or less.

Example Using the steel foil with a thickness of 100 Jim used in Example 1, chemical conversion treatment and box annealing were performed in the same manner as in Example 1, and during honing, honing was performed using a water-based honing solution that does not contain a chemical conversion treatment agent. Even after honing, the product was made into a finished product without any chemical conversion treatment.

Comparative Example 6 The 10011 m thick steel foil used in Example 1 was subjected to chemical conversion treatment and box annealing in the same manner as in Example 1, and was made into a product as it was without heat treatment.

For the above Examples 1 to 7 and Comparative Examples 1 to 5, the workability in each manufacturing process and the performance evaluation test of the finished product were conducted and the results are summarized in Table 1.

The performance test items and test methods are as follows.

A. Workability (1k) Steel foil is applied to a metal with a sharp corner. The degree of wrinkles was evaluated based on the maximum depth that could be squeezed without causing breakage and the degree of wrinkles on the side wall.The degree of wrinkles was scored as follows.

O: Almost no wrinkles Δ: Slight wrinkles on the upper edge, Practical 1 Almost no problems X:
Large wrinkles occur, impractical B Corrosion resistance (a) Corrosion resistance without coating 0) Moisture type test A sample sheared to 100 x 100 vm' was 40C1
The rate of rusting was investigated when suspended for 100 days in a humidity chamber with a relative humidity of 95%.

(cO stacking rusting test 100 x 100 ws2 sheared steel foils were stacked, sandwiched between two sheets of 20mm thick, 120 x 120 sm2 sheets, tightly tied together, heated at 40°C, relative humidity 85%. (b) Corrosion resistance after painting (f) Under-paint corrosion test...humidity type test Currently used as a paint for canned food. A test was carried out on a product coated with a medium-based paint with a coating thickness of 45 rRg/cfI12.After painting, cut out a 100 x 100 x 2 piece and remove the scratches marked with an X that reach the base with a sharp knife diagonally. The entire body was placed in a humidity chamber at 40° C. and a relative humidity of 85° C. for 4 days, and the state of rust under the paint film was examined.

Q: There is almost no filamentous rust from the eaves.

Δ: ＃ 51 or less.

×: 6■ or more and 10m or less.

XX: ＃ 10■ or more.

(b) Under-coating corrosion test...Salt-citric acid solution immersion test Steel foil coated in the same manner as in the previous section (f) 50 x 50I
A specimen of II12 was cut out, a scratch was made along the entire diagonal line with a sharp knife reaching the base of the X mark, and it was immersed in an aqueous solution at 55°C containing 1.5% each of common salt and citric acid for 96 hours. The corrosion status and adhesion status of the paint film were examined by taping.

O: No spread of corrosion on the eaves and no peeling of the paint film Δ:
# 0.5- or less paint peeling small
# Paint film peeling of 1 mm or more is almost the entire surface C Paint film adhesion Steel foil coated in the same manner as in the previous section n-(b)-(c),
After immersing in pure water heated to 100℃ for 1 hour, immediately reach the base of the IW interval with a sharp knife,
A taping test was conducted to examine the peeling status of the paint film, and the evaluation was based on the area ratio (A) where the paint film peeled off.

D Adhesion of plastic film (a)/! J:'? Adhesiveness of Lentele 7 Talate Film Using thermoplastic/9 ester adhesive, 30μ thick polyethylene terephthalate was crimped using a heated roll to determine the adhesion when laminated to steel foil. It was evaluated using the following method.

0) A cylinder with a diameter of 60+s was drawn with the polyethylene terephthalate side facing the inner surface, and the presence or absence of peeling of the film was examined.

(b) The peeled area ratio of polyethylene terephthalate was investigated when it was immersed in pure water at 100° C. for 1 hour, immediately placed on a base at 2 m intervals using a sharp knife, and then punctured and taped.

(b) Adhesion of polyzorolene film (a)
The adhesiveness when laminating I-lipropylene was evaluated in the same manner as above.

The test results are shown in Table IK.

As shown in Examples 1 to 7 in Table 1, an annealing anti-seize coating was formed [by box annealing, no seizure was observed even with steel foils with a thickness of 100 μm or less, and by liquid honing and tempering. It can be seen that the processability is improved by doing so (see Comparative Example 6).

Furthermore, as shown in Examples 1 to 6, it can be seen that when the chemical conversion treatment is performed simultaneously with the honing treatment or after the honing treatment, corrosion resistance and adhesion to organic resins are also excellent (Comparative Examples 6 and 6). (See Example 7) (Effects of the Invention) The present invention improves the material quality of cold-rolled steel foil, or improves the corrosion resistance and adhesion with organic resin at the same time as the quality of the material. Coupled with cost reduction based on high productivity, the amount of steel foil can be expanded.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of equipment for performing the liquid honing process of the present invention. 1: Steel foil, 2: Conductor roll, 3: Hoyung gun, 4: Abrasive cleaning gun, 5:
Electrode, 6: Washing tank, 7: Dryer.

Claims (4)

[Claims] (1) Plate thickness 10 to 100μ rolled by cold rolling
After degreasing or at the same time as degreasing, an annealing anti-seizure film is formed on the surface of the steel foil of No. m, and it is wound into a coil.Then, the coil is brightly annealed, and then liquid honed using an aqueous solution containing an abrasive. A method for manufacturing steel foil with excellent workability and adhesion, which is characterized by subjecting it to heat treatment. (2) A method for producing a steel foil with excellent workability and adhesion according to claim 1, which uses a liquid containing a chemical conversion treatment agent and an abrasive as the honing liquid. (3) Plate thickness 10 to 100μ rolled by cold rolling
After degreasing or at the same time as degreasing, an annealing anti-seizure coating is formed on the surface of the steel foil of No. m, and then it is wound into a coil.Then, the coil is brightly annealed, and then an aqueous solution containing an abrasive and a chemical conversion treatment agent is applied. A method for producing a steel foil with excellent workability and adhesion, characterized by performing a refining treatment by applying liquid honing using a honing liquid, and subsequently forming a chemical conversion coating using the honing liquid. (4) A method for producing a steel foil with excellent workability and adhesion according to claim 3, which comprises forming a chemical conversion film by electrolytic treatment after liquid honing.