JPS6033398A - Electrolytic treatment method - Google Patents

Abstract

PURPOSE:To enable high speed electrolytic treatment, in performing the electrolysis of a metal web by using a power source for outputting an asymmetric alternating wave form, by providing two or more of electrodes opposed to the surface of the metal web, and separately applying asymmetric alternating voltages opposite in polarity to each other between each of electrodes and current supply mechanisms. CONSTITUTION:A metal web 1 is electrolyzed by using a power source for outputting an asymmetiric alternating wave form. In this case, two or more of electrodes opposed to the surface of the metal web, for example, three electrodes 6, 7, 8 and current supply mechanisms 10, 11 are provided. In this structure, asymmetric alternating voltages opposite in polarity to each other are separately applied between each of the electrodes 6, 7, 8 and the current supply mechanisms 10, 11 nearly all the time.

Description

[Detailed description of the invention] The present invention relates to a method for electrolytically treating a metal web.

A metal web is passed between a pair of opposing electrodes installed in an electrolytic solution, or a metal web is passed near a pair of electrodes installed to face one side of the metal web. The indirect power feeding method, or electrolysis, is a process in which a direct current or an alternating waveform current is passed between these electrodes with additional heating, thereby chemically treating both or one side of the metal web at once. The method is a technology that is widely practiced industrially. Electrolytic methods in which direct current is applied include plating, anodizing, etching, etc., and known methods in which alternating current is applied include degreasing, etching, etc. These techniques involve creating a surface with a special function imparted to one side of the metal web by electrochemical treatment, or creating surfaces with similar functions imparted to both sides of the metal web. It is done for a purpose. In particular, an advantage of the indirect power supply electrolysis method in which a voltage is applied between a pair of electrodes facing each other to electrolyze a metal web passing through the center is that a large current does not flow in the longitudinal direction of the metal web, so large current electrolysis It has the advantage that a surface with desired functionality can be created by high-speed electrolysis. For example, it is a widely known technique in the fields of foil eggs for capacitors using aluminum foil as a metal cube, or electrolytic surface treatment of aluminum strips for printing plates.

Furthermore, as a method using direct current, the case of anodizing an aluminum strip is also well known. However, the problem with these techniques is that, although it depends on the method of processing the metal web, the processing voltage is generally slightly lower than that of methods that directly supply power to the web using rolls or contact brushes, and can be quite high. It has been pointed out that, for example, in cases where DC current is used, there may be cases where the DC power supply method has greater benefits.

In addition, in cases where alternating current is used, the above-mentioned indirect power feeding method has a very excellent advantage in cases in which both sides of the board are subjected to approximately equal treatment, but treatment with slightly different functions is required. It was difficult to make both of them happen at the same time. In general, the latter case is rare; for example, in the manufacturing technology of etched foil for capacitors using aluminum strips mentioned above, a commercial alternating current with a symmetrical waveform is passed between electrodes facing each other in hydrochloric acid. Therefore, it is common to create the same etched surfaces on both the front and back sides.

As described above, the direct power supply method is selected depending on the purpose of the process, whether the current used is direct current or alternating current, and the magnitude of the current.

However, Patent No. 1,028,098, Special Publication No. 55-1
An asymmetrical alternating waveform current is used, as described in Publication No. 9191. In the electrochemical treatment method for metal webs, when looking at the treatment on the side facing each electrode of the web that passes between two electrodes placed opposite each other in the liquid, the waveforms are opposite. The web is electrolyzed, and both sides of the web are coated with Patent 1. ．． No. 028,098, Special Publication No. 1983-
It becomes impossible to carry out the process described in the 19191 publication. Furthermore, even when electrolysis is performed by installing one or more pairs of electrodes facing one side of a metal web and applying voltage, the desired effect can be achieved because electrolysis with opposite waveforms is applied over and over again. It has been difficult to stably manufacture the coated surface. Using these asymmetrical alternating waveform currents, it is possible to perform the same treatment on both sides of a metal web by the above-mentioned method for double-sided processing of a web, or to perform a desired treatment on one side of a web by the above-mentioned method for single-sided processing. The method is to supply power to the metal nib separately, either by direct power supply using roll power supply, etc., or by submerged power supply using a liquid that is harmless to the target treatment, in a location separate from the processing tank. I have no choice but to rely on

Generally, in these methods, since the processing current flows through the metal web in the length direction of the web, there is a constraint that a sufficient current cannot flow due to heat generation due to the voltage drop in the web. was there. Regarding direct power supply mechanisms such as roll power supply, an increase in the power supply current tends to cause undesirable phenomena from the viewpoint of stabilizing power supply, such as damage to the web and roll due to the generation of sparks. One important technique is how to stably increase power supply capacity. In addition, as mentioned above, especially in processing using an asymmetrical current waveform, when applying equal f, 'i: or similar processing to both sides of the metal web, as described above, it is necessary to Due to power supply constraints, they were forced to sacrifice productivity significantly.

The present invention has been made diligently to solve the problems of the prior art, and includes:
Electrochemical treatment of metal webs using asymmetric alternating waveform currents' [! l! In the present invention, we developed an electric power feeding method that enables significantly faster processing than conventional methods by increasing the load on the power supply roll by N.

That is, in the present invention, when electrolyzing a gold F, i web using an electric current υζ (which outputs an asymmetrical alternating waveform), two or more short plates are installed facing the surface of the metal web, and A 1B mechanism is provided, and each of the πi and l1ii and the power supply 1
3 i74, most of the time so that the polarity is reversed) .

In Mizumoto Town, it is possible to slightly change the processing on both sides of the Kin^・li Miranib, or to change both sides independently so that each has its own function, or to make both sides all the same. Of course it is possible. Furthermore, in the case of single-sided processing, C also enables significantly higher processing speed than conventional methods.

The present invention will be described below with reference to the accompanying drawings. FIG. 1 is an example of a case in which both sides of a metal web are processed in the same way by an asymmetrical waveform using the current state-of-the-art direct feeding method.

1 is a metal web to be treated, which is conveyed through an electrolytic cell 2 by means of pass rolls 3°4.5. The electrolytic cell 2 is filled with an electrolytic solution, which is supplied from the bottom of the electrolytic cell by a circulation system (not shown), overflows from an overflow weir provided at the top of the electrolytic cell, and is pumped back into the electrolytic cell. Returning, the cycle continues. There are three electrodes 6 inside the electrolytic cell.
, 7.8 are installed, and the metal web is connected to the electrodes 6 and 8,
and passed between electrodes 8 and 7. Reference numeral 9 denotes a power supply roll, which presses the metal web 1 against the pass roll 3 to supply power. The three electrodes mentioned above are electrically coupled, and a power supply device 10 is connected between the three electrodes 6, 7.8 and the power supply roll 9 as shown in the figure. An asymmetrical alternating waveform voltage is applied between the metal webs 1 and 1.
When passing between electrodes 6 and 8 and between electrodes 8 and 7, both sides of the will be electrolytically treated. FIG. 2 shows the output of the power supply device 10. As an example of an asymmetrical alternating waveform voltage,
A square wave voltage is schematically shown. Further, FIG. 3 schematically shows the voltage and current during electrolysis on both sides of the metal web. The surface of the metal web 1 on the electrode 6, 7 side that is powered by the power supply roll 9 is designated as A, and the surface on the opposite side is designated as B.
Then, there is a gap (1) in Fig. 3 between the A side and the electrodes 6 and 7.
A voltage with a waveform like this is applied, and at this time, the voltage @6,
A current having a waveform as shown in (2) in FIG. 3 flows through the terminal 7. On the other hand, a voltage with a waveform as shown in (3) in Figure 3 is applied between the B side and the electrode 8, and at this time, a current with a waveform as shown in (4) in Figure 3 is also applied from the A side to the electrode 8. flows.

Therefore, the current supplied from the power supply roll 9 to the metal web 1 is the amount shown by the sum of (2) and (4) in FIG. 3, and it has a waveform as shown in (5) in FIG. become. In Figure 3, the center is zero, the top is positive, and the bottom is negative. In this way, in direct power supply using roll power supply, if you want to perform the same treatment as the pressure on both sides of a metal web, it is necessary to supply the combined amount of current flowing to each surface, and this is necessary for high-speed electrolysis, etc. This has become a serious failure requirement when it is required to supply relatively large currents.

FIG. 4 shows the present invention, which has been intensively researched to solve such problems. That is, when feeding power from the power supply roll 9 to the metal web 1, at least 2
It is characterized in that the waveforms of the power supply 10°11 divided into three or more are controlled so that the positive and negative polarities are less likely to coincide with each other, and power is supplied. FIG. 5 partially relates to the case of double-sided electrolysis shown in FIG. 4, and is an example in which the phases of both power supplies 10 and 11 are reversed and voltages of the same waveform are supplied, and the present invention will be explained in detail. prepared for. That is, during the entire cycle in which the 0 side of the metal web 1 is positive with respect to the counter electrode 8 in the 4th figure pressure, the power supply 17 is electrolyzed so that the 0 side of the metal web 1 is negative with respect to the counter electrodes 6 and 7. It shows that. That is, regarding -2, a voltage waveform shown in FIG. 5(3) is applied between the metal phenol 1 and the counter electrode 8 by the power source 11. Regarding the plus and minus of waveforms, see Part 3.
As in the figure, the top is positive and the bottom is negative. At this time, there is a gap between the 0 side of the metal web 1 and the counter electrode 8 as shown in (4) in FIG.
A current with the waveform shown will flow.

On one side, metal web 1 and counter electrodes 6 and 7
A voltage waveform shown in FIG. 5(1) is applied by the power supply 10 between the two. At this time, the current flowing between the metal web l and the counter electrodes 6 and 7 is calculated in the same manner as in FIG.
) is the waveform shown.

The current flowing to the opposite electrode through the 0 surface and the 0 surface is positive when it is positive for the 0 surface, and is negative for the 0 surface.
After the surface changes from positive to negative, the 0 side gradually remains negative and then changes to positive.

Therefore, the period during which the polarities of the currents on the 0-plane and the 0-plane are the same is an extremely short period from when the 0-plane changes from positive to negative to when the 0-plane changes from negative to positive, and during this period, the power supply roll 9, the currents only for the current supplied to the metal web 1 and the current for the 0th surface are only added. Looking at other times in one cycle, the polarity of the current on the - side and the 0 side is opposite, and the current supplied from the power supply circuit 9 to the metal web 1 is on the ■ side and the opposite side. This is shown to be a difference in the current value flowing between the opposite electrodes ((5) in FIG. 5). In this way, the current supplied from the power supply roll 14 to the metal web 1 can be significantly reduced, and in the case shown in (5) of FIG.
The power supply current can be reduced to about % of the case shown in (5) in the figure. Figures 4 and 5 show the current 1o and the power supply 1
This is a case where both power supplies are controlled by the synchronization circuit 12 so that the proportion of the period in which the polarities of the output waveforms of the output waveforms of the first and second outputs coincide with each other in the total cycle is minimized, but the present invention is simply limited to such a case. However, the present invention also includes an electrolysis method in which the period during which the polarities of both output waveforms match each other is minimized. Further, even when the two waveforms are different, the present invention is effective, and it is possible to perform electrolytic treatment that imparts different functions to the front and back surfaces of the metal web while effectively reducing the power supply current. Further, in the present invention, a side in which a power supply roll is installed as a power supply mechanism is described, but even if the power supply mechanism is replaced with liquid power supply using an electrode, the effects of the present invention will not change.

As the electrolytic solution that can be used in the present invention, conventionally known ones, that is, acidic aqueous solutions containing halogen ions or nitrate ions that have the property of attacking aluminum, can be used. Examples of preferred oxidizing aqueous solutions for bamboo include aqueous solutions containing hydrochloric acid, nitric acid, or mixtures thereof as electrolytes, in each case with an electrolyte clarity of about 0.5% to about 5% by weight, more preferably is 0.8
Selected from the range of ~3 double view%. These aqueous solutions include
Furthermore, corrosion inhibitors (or stabilizers) may be included. For example, in the case of a hydrochloric acid electrolytic bath, chlorides such as subsalt chloride, ammonium chloride, sodium chloride-aluminum chloride, trimethylamine, triethylamine, dimethylamine.

diethylamine, methylamine, ethylamine, carbamic acid, triethanolamine, jetanolamine,
Amines such as monoethanolamine, diamines such as ethylene diamine and hexamethylene diamine, formaldehyde, acetaldehyde9. Examples include aldehyde 9 such as rL-hexylaldehyde, acids such as phosphoric acid, chromic acid, and nitric acid.In the case of a nitric acid electrolytic bath, zinc nitrate,
Examples include nitrates such as ammonium nitrate and sodium nitrate, the above-mentioned monoamines, diamines, and aldehydes, as well as phosphoric acid, chromic acid, and sulfosalicylic acid. The amount of these corrosion inhibitors added to the electrolyte is 0.
Preferably, the amount is selected from the range of 0.05% to about 3% by weight.

Further, the temperature of the electrolytic solution is preferably in the range of 20°C to 40°C.

Next, the effectiveness of the present invention will be explained using an example of electrolytic etching of an aluminum plate for printing plates.

First, the voltage waveform used in this experiment is an asymmetrical square wave alternating waveform as shown in Figure 2, and as a fixed condition, V
F = 24V, VR = 14v, tA = 6.
771LSec.

'C==10.077LSec, the electrolytic cell basically has the structure shown in FIG. 1, and the dimensions of each part are roughly as follows.

The diameter of the power supply roll 9 is 100 mm, and the area of the power supply part is 20 mm.
The material of the roll is aluminum alloy JISA105.
It is 0. The pass roll 3 facing the power supply roll has a diameter of 1
The surface length is 50 mm at 0' Omm, and the roll material is hard rubber. A summary of Denmension in Electrolytic 2,
It is as follows. In other words, the inner dimension of the fence is 700 mm deep.
mm, width 200 mra, depth 55 mm, and the diameter of the pass roll 4 at the lower center of the tank was 100 rnm. Three graphite electrodes are installed inside this tank, and the graphite electrodes 6 and 7 along the side walls on both sides of the tank have a thickness of 20 mm and a width of 50 m.
m, the maximum length in the liquid that can face the aluminum web 1 is 500 m. The central graphite electrode 8 has a thickness of 40 mm, a width of 50 mm, and a maximum length in the liquid facing the aluminum web 1 of 500 mm. The width of the aluminum strip 10 is 50mm, the thickness is 0.3mm, and the material is A10.
It is 50. The aluminum web 1 has three electrodes 6, 7
, 8, and was turned by the pass roll 4 at the lower center of the tank. The electrolysis length of the aluminum web 1 was determined by controlling the overflow of the electrolytic solution level, and the length of the aluminum strip facing the graphite electrode was determined by adjusting the liquid level.

In addition, an electrolytic solution was showered on the contact area between the power supply roll and the aluminum strip to prevent discharge and to cool the aluminum IJ tube that was not immersed in the liquid between the power supply part and the electrolytic part. The above are common conditions. A comparative example will be described below.

Comparative Example Three graphite electrodes 6, 7.8 are electrically short-circuited, and the voltage shown in FIG. We conducted an experiment to find out (Figure 1). The load between the power supply roll and the roll facing it was set to 4, and the aluminum web was etched with caustic soda and washed. l&, passed between the power supply roll 9 and the pass roll 3 and led to the electrolytic cell. The liquid level height was controlled so that the length of the aluminum strip facing the graphite electrode measured from the lower end of the graphite electrode was 20 (l mm), and the electrolytic area of the aluminum web 1 was 4 mm.
dm2, and 80 cIn so that the electrolysis time is 30 seconds.
/l;+ where the aluminum web 1 was conveyed.

The peak current flowing when aluminum became positive to the graphite electrode was approximately 20 OA, and the peak current flowing when aluminum became negative was approximately 100 A. The signals taken from the shaft placed in the current flow path between the power supply roll and the power source are converted to absolute values and averaged.
When converted to an average current, the current at this time was 115 A, and an extremely stable current was observed. Also patent 10280
It was confirmed that the good sand surface described in Example No. 98 was stably produced on both sides of the plate. The electrolyte level was further raised by 50 mm to make the electrolytic area of aluminum web 1 5 d, m2, and at the same time, the conveyance speed of aluminum web 1 was increased to 1 m.
When the power supply was set to 15+, the average current increased to 145 people, but the current sometimes fluctuated rapidly, making it impossible to provide a stable power supply. Therefore, in this case, the upper limit that can stably supply power is about 1158.

Embodiment The power supply was divided into two parts having equal periods and connected as shown in FIG. 4, so that the phase of the output waveform of each power supply was as shown in FIG. Examples according to the present invention will be described.

One of the two power supplies is connected between the power supply roll 9 and the two graphite electrodes 6 and 70 in contact with the outer wall of the electrolytic cell, and the remaining power supply is connected to the power supply roll 9 and the central graphite electrode 8. The output of each power source was monitored by converting the shaft output described in the comparative example in the same way. The length of the aluminum web 1 facing the graphite electrode when the outputs of both power supplies were each equal to 115 A described in the comparative example was 4.00 m.
m, and the conveyance speed of the aluminum web is 1
601 minutes, which is twice the value of the comparative example, was obtained. The power supply from the power supply roll was extremely stable, and the sand surfaces on both sides of the IJ tube were the same as those described in the example of Patent No. 1028098. Furthermore, when the liquid level was raised by 100 mm and the aluminum strip conveyor speed was investigated, the current of each power source was 140 A using the same expression as before, and it was verified that the same sand surface as before was stably generated. .

As shown in the comparative examples and examples above, the method of the present invention lowers the limit of power supply by the power supply roll by 5% compared to the conventional method.
It has been found that by avoiding this, at least the high-speed electrolysis on the conventional can plate can be performed stably.

Although the contents and examples of the present invention have been described above with respect to double-sided electrolytic treatment of a metal web, the present invention is also applicable to continuous electrolytic treatment of one side of a metal web. FIG. 6 is a diagram similar to FIG. 4 in which the present invention is applied to continuous electrolytic treatment on one side, and similar effects and effects can be obtained.

[Brief explanation of drawings]

FIG. 1 is a side view showing a conventional double-sided electrolytic treatment method for metal wafers, FIG. 2 is a diagram of asymmetrical alternating waveforms used in the electrolytic treatment, and FIG. 3 is a diagram of voltage and current waveforms during the electrolytic treatment according to FIG. FIG. 4 is a diagram showing an example of the method for electrolytically treating both sides of a metal web according to the present invention, and FIG. 5 is a diagram of voltage and current waveforms during the electrolytic treatment according to FIG. 4. 1... Metal web 2... Electrolytic cell 3.4. Sensation...Pass roll 6.7.8...Electrode 9...Power supply roll 10.11..., power supply device (3 others) Fig. 1 Fig. 3 Fig. 4 ts5 Continuation of Fig. 1 page 0 Invention Author: Mori 1) Akira 454 Hatachi, Kanbara-cho, Ibara-gun, Shizuoka Prefecture Japan Light Metals Research Institute Co., Ltd. Internal procedure amendment December 1981 Special r "Kenbe 141859 No. 2, 1 name of invention Electrolysis Processing method 3, relationship with the person making the amendment, patent applicant name (520) Fuji Photo Film Co., Ltd. (Kasumigaseki Building Post Office, P.O. Box 49, Yumiei Patent Office, Tel: (581)-9601, Han 1987)
November 8, 2015 (Delivery date: November 29, 1982. 6 Number of inventions increased by amendment 0 Iris... Added.

Claims (1)

[Claims] When electrolyzing a metal cube using a power source that outputs an asymmetrical alternating waveform, two or more electrodes are installed opposite to each other on the surface of the metal web, and a power supply mechanism is further provided, and each of the electrodes and the power supply mechanism are connected to each other. The feature is that asymmetrical alternating voltages whose polarities are reversed most of the time are separately applied between them. Electrolytic treatment method for metal web