JPS6067700A - Electrolytic treatment apparatus - Google Patents

Abstract

PURPOSE:To provide an electrolytic treatment apparatus enabled in high current density treatment even in using an alternating wave form current and capable of obtaining a uniform treated surface, constituted by providing a compact soft start zone for performing low current density treatment to the metal web inlet part of an electrolytic cell. CONSTITUTION:A metal web 21 is guided into a cell and conveyed in the cell while wound around a drum roll 23 to be transferred out of the cell. During this time, an electrolytic liquid 28 is supplied by a liquid supply part 29 arranged directly under the roll 23 to fill the cell and discharged out of the cell to be forcibly recirculated through a recirculation tank 31 by a pump 32. On output terminal of an alternating wave form power source 33 is connected to a contact current supply roll 27 and the other terminal thereof is connected to electrodes 25, 26 and the electrode 34 of a soft start zone to apply voltage. At this time, said other terminal is connected to the electrode 34 through a resistor 36. By this method, current control to the electrode 34 can be performed and the reaction at this part is suppressed to current density of 10A/dm<2> or less to form the soft start zone and, in performing electrolytic etching treatment to the web 21, continuously etching treatment excellent uniformity can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to provide a continuous electrolytic treatment tank that is capable of performing electrolytic etching treatment with inconsistent uniformity when continuously performing atjFF etching treatment on a metal web using an alternating waveform electric current. It is something to do. The method of electrolytically etching the surface of aluminum 2, iron, etc. has been widely put into practical use, and alternating waveform current is generally used for the purpose of improving the required quality and reaction efficiency. For example, in Japanese Patent Application Publication No. 2003-2011, an offset printing plate is supported by using an alternating waveform voltage applied so that the anodic voltage is more than the negative cathode dark voltage during the electrolytic roughening process of an aluminum plate. There is a description that the surface roughening treatment which is excellent in terms of physical properties results in iiJ performance. Usually electrolytic etching treatment is 1~
Current density 10 in an acidic bath such as 3% nitric acid or hydrochloric acid.
A/dm2 to 10 (performed at 7 A/dm2).

When using an alternating waveform current, for example, when an aluminum plate is used as the metal web, the anode local time is Al→A13++J
A dissolution reaction of Q occurs and during the period of the cathode, H++e-+-!
-H2 cow, and hp3+→3 Q l-1→A#(OH)
Hydrogen gas generation ash L1 of a; At the same time, a reaction of producing hydroxyl and aluminum soot occurs on the aluminum plate.

These reactions occur in mega depending on the frequency of the power source.

It is generally possible to obtain the required roughened surface by controlling these basic reactions by controlling the type of bath, degree of recording, temperature, and electrical conditions such as current density and applied electricity.

However, when using an alternating waveform current, there is always a difference between the part where the process 11 starts due to the dissolution reaction and the part where the process starts due to the smut forming reaction, depending on the current cycle when the metal web is introduced into the electrolytic cell. These differences naturally occur depending on the frequency of the power supply. For example, processing speed ROM is 7M, power supply frequency is tOH
When Z is 7, the difference occurs in the longitudinal direction of the metal web and in the pitch of J. This difference is extremely important when excellent treated surface uniformity is required. That is, the difference in reaction at the start point may result in a non-uniform treated surface even after the treatment is completed.

Considering the mechanism by which these non-uniformities ('+) occur, it is natural that the higher the current density and the higher the processing speed, the stronger the unevenness becomes.However, from the perspective of mass production, high processing speed and High current density processing is desired, and defects resulting in non-uniformity are a very inconvenient problem from the viewpoint of sewing production ratio.The prior art does not disclose any solution to this problem. There is no choice but to suppress the overall current density to such an extent that these non-uniformities do not become a problem.The present invention provides an electrolytic processing apparatus capable of high current density processing that eliminates these defects.The present invention The feature of the electrolytic treatment apparatus according to the present invention is that a soft start zone for performing resistive current density and one pressure treatment is provided in the one-cell portion where the electrolytic treatment starts.

As a result, defects caused by differences in initial reactions are substantially eliminated, the treatment tank as a whole is capable of high current density treatment, and a uniform treated surface can be obtained at high treatment speed.

Hereinafter, the present invention will be explained in more detail with reference to the accompanying drawings. FIG. 1 shows a conventional radial type electrolytic cell. The metal web l is introduced into the cell by a guide roll 2, wrapped around a drum roll 3, and transported inside the cell,
It is transported outside the cell by the guide roll t. j, A are electrodes arranged in pairs on the metal web /, and the distance (pole spacing) between the metal web / and the pole t, X is j,! 1
0 is a contact power supply roll that contacts the metal web and is driven to rotate at the same speed as the web. Also, electrolyte f
-U The electrolyte is supplied from the supply section located directly below the drum roll, filling the cell with ia7'/i! Liquid discharge part 10
The liquid is discharged to the outside of the cell above the liquid discharge section, passes through a circulation tank //, and is forcedly circulated by a pump/2 or the like.

Also, /3 is an alternating waveform power supply, and one of the power supply output terminals is connected to the contact power supply roll 7, and the other is connected to the poles j and 4, and a voltage t;r is applied thereto. In this way, it is possible to subject metal webs to continuous electrolytic etching treatment. A smut forming reaction occurs on the surface of the continuously running metal web. By alternately repeating these dissolution reactions and smut formation reactions for 120 seconds, the surface roughening treatment becomes possible. However, the moment a certain portion of the metal web is introduced into the cell, the reaction period of the metal web within the cell is either an anode or an 18:pole. As a result, in the υ metal web, portions formed by the dissolution reaction as the first reaction and portions started by the smut formation reaction appear alternately at the 'ThTh wave frequency. In high tTL flow density processing of 30 A,/dm2 or higher, the effect of this difference may remain as a history until the end of the processing, resulting in regular horizontal step-like processing non-uniformity./OA, When processing at a low current density of less than / dm2, the effect is so small that it does not become a problem, and it is possible to ensure a uniform product, but from the viewpoint of precision production, the reaction time becomes longer, which is inconvenient. Figure 2 is W
Figure J1 shows the current distribution in the longitudinal direction of the metal web from the start point A of the tube treatment to the end point B of the electrolytic treatment directly in the conventional equipment.
．． 'As more smut is accumulated on the web, the electrical resistance becomes t', which results in a downward-sloping curve, 'n, r, I'+'The current density is highest at the beginning of the F process. but? 'F+l'! 'l. FIG. 3 does not show an embodiment of the device of the present invention. The metal web λ/ is introduced into the cell by a guide roll 2.2 and a drum roll, 2
3 and transported inside the cell, and then transferred to the outside of the cell by guide rolls Jj-. 2Ji.

Reference numeral 26 denotes an electrode, which is arranged opposite to the metal web 21. Further, 3≠ is the electrode of the soft star l-zone, that is, the electrolytic treatment start part, and the electrode 3 is the insulator 3! made of an insulator. electrically isolated by , 27 are contact power supply rolls that contact the metal web and are driven to rotate at the same speed as the web. Further, the electrolytic solution λ♂ is supplied from the electrolytic solution supply section λ disposed directly below the drum roll, fills the inside of the cell, and is discharged outside the cell from the electrolytic solution discharge sections 3θ and 30' through the circulation tank 31. It is forced to circulate through the pump 32, etc. Also, 33 is an alternating waveform power supply, one of the output terminals is a contact power supply roll, 27 is the other, and the other is an electrode -2K.
, , 24 and the electrode 3 of the soft start zone and apply a voltage. This 11η soft start zone electrode 3
Connect to Hiro through resistor 3Af. In this way, the current to the soft start zone electrode JII can be controlled, and the reaction in this part can be suppressed to a current density of /OA/A2 or less, thereby forming a soft start zone. Fig. 3 shows the current distribution along the length of the metal-unib from the electrolytic treatment start point A' to the electrolytic treatment end point B' in the apparatus of the present invention. In Fig. 3 and Fig. 3, the length of the start zone is j-λθ, and the electrolysis time is approximately (7te!θ~-〇omS), but in order to eliminate the influence of the difference in the initial reaction, For example, if the processing speed #jOm/M5 power frequency is 40Hz and the soft start zone length is 100flWn, then 007
A 2 second low current density treatment is performed first. This corresponds to 7 current cycles (/period o, o/18>).Even if a high current density treatment of J O-/00A/dm2 is performed after this, the treated surface has excellent uniformity* (4) I was able to do something.

Also, according to the present invention, the length of the soft start zone that is necessary is I
ri! 〜λθ and the reaction time is jθ〜2o'o7
The overall reaction speed is about 7LS, which is extremely short compared to the time j~/λO seconds, so the provision of this zone does not substantially affect the overall reaction speed.

As described above, the electrolytic cell according to the present invention is characterized by providing an extremely compact soft start zone at the cell entrance, which enables processing at a density comparable to that of a streetcar even when using an alternating waveform current, and provides excellent uniformity. It is possible to obtain 1fii before processing.

Therefore, in Fig. 3, a resistor 3z is provided in the electric circuit to form a soft start zone, but the resistor 36 is not provided and the soft start zone is created at the cell entrance by considering the position and shape of the electrode 3t. It is also possible to form zones to achieve the object of the invention. In FIG. 1, the electrode 3' is set so that the distance between the soft start zone electrode 31I located at the cell entrance portion and the full set web 2/ is wider than the distance between the electrode 2A and the metal web 2/. This shows an example in which the total electrical resistance in this part is increased by this. Normally, in the case of @solution etching, the distance between the electrodes is j to so'rmn, but it is preferable that the distance between the electrodes in this part is j, which is 10 times that value. In addition, the soft start zone electrode 3 is shown in the figure.
An example is shown in which the electrical resistance is increased by cutting out a part of the metal web 21 and shortening the length facing the metal web 21. In this case, the upper surface of the cutout is in direct contact with the electrolyte. In addition, in Fig. 7, a 17+N flow pipe 37 is provided at the electrolyte outlet part so that a space in front of the soft start zone electrode 3 becomes a space filled with the electrolyte. And the two sides of the electrode (1 contact, 1 contact)
9'f processing action is performed. This is a method in which a portion of the current that can be supplied to the soft start zone electrode 31 is diffused into this space. In FIG. 7, dotted lines indicate lines of electric force that carry out electrolytic treatment at the soft start zone electrode 3. It is also possible to form a soft zone at the cell entrance by the method described in C). Contact supply 1 as an illustration of an embodiment of the invention
'IT, a contact power supply system using a roll or a radial type cell was used, but the feature of the present invention is that a compact soft start zone is provided at the cell entrance, and the power supply system is a liquid power supply system. The cell may also be horizontal or vertical. Examples according to the present invention will be shown below.

Comparative example 1゜Thickness O・7H under the following processing conditions in the apparatus shown in Fig. 7
An aluminum web having a width of ~3 ootam was subjected to continuous electrolytic etching treatment.

Processing conditions Processing speed Jゝ〃〃/-M Electrolytic solution L nitric acid, 3j 0C Current waveform Rectangular alternating current waveform, frequency t OHZ Current density OA/dm2 Reaction time J seconds between poles IO cocoon As a result, frequency 40 ■: Nonuniformity occurred on the surface of the rough surface 16 with lz, /, Jria pitch. It was divided into a part where circular pits with a diameter of j to 10μ were gathered and a part where irregularly shaped bits were gathered.

Example 1: Using the apparatus shown in FIG. 3, a thickness of 0. /rran, width 30
Comparative Example 1. Continuous etching treatment of 0B aluminum web.
It was carried out under the same processing conditions as shown in .

At this time, the length of the soft start zone electrode 3v is 100,
The resistor 3t was adjusted to +p and 'a so that the current density at this point was 10 h/dm2.

As a result, a rough surface with excellent uniformity was obtained as an offset printing plate support. A circular bit with a diameter of j to 10 μm was obtained uniformly over the entire surface.

Example 2 No. 2! Thickness 0, / mm, width 3 using the device shown in the figure.
Continuous etching treatment of a 00WM aluminum web was carried out under the same treatment conditions as in Comparative Example 1.

At this time, soft start zone electrode 311'l-J, 10
orrrm, and the distance between the poles and the metal web was 7θ m.

As a result, Example 1. The result is similar to i(Jare7ξ).

Example & No. Thickness ', 1w, 1130 using the apparatus shown in the figure
Continuous etching treatment of an aluminum web between 0 and 0 was carried out under the same treatment conditions as in the comparative example.

At this time, the soft start zone electrode 3" has a length of 100 mm and is cut out diagonally to determine the length of the surface facing the metal web.
+1−≠oram. Moreover, the upper surface of the notch was made to come into direct contact with the electrolyte. At this time, the liquid level of the ms liquid discharge part was 777+YI++ higher than the notched corner.

As a result, Example 1. Similar results were obtained.

Thickness o, i mark, rlJ3θθ
Comparative Example 1. Continuous etching treatment of a group of aluminum webs. It was carried out under the same processing conditions. At this time, the height of the overflow pipe 37 was set to 10"rmrl, and pressure was applied so that the upper surface of the soft start zone electrode was also directly subjected to the Tli decomposition process.

As a result, Example 1. Similar results were obtained.

As mentioned above, if the device of the present invention is used, it is possible to perform continuous electrolytic treatment with good finish quality due to the provision of a soft start zone, and in addition to stabilizing the process, side effects such as eliminating maintenance and inspection work and reducing costs are expected. can.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of a conventional continuous electrolytic treatment apparatus, and FIG. 2 is a diagram showing its current distribution. FIG. 3, FIG. 5, FIG. 6, and FIG. 7 are schematic explanatory diagrams showing the structure of the electrolytic treatment apparatus according to the present invention, respectively,
The figure below shows its '+1. #M is a diagram showing the distribution. /,,2/...Metal web J,,2J...Tram roll! , = Zj, lr, 2t...i'l'j ihe7
．． 27. Old... Contact 6t (p roll 34t, 3≠
', 3μ''・Old...Soft Star 1 Electrode 3!...Insulator/3,3!...Power supply patent applicant 6 (Shiyoshin Film Co., Ltd. Figure 2, Figure 4) Figure one six feet:, 44, 4 parking force 6T, 3rd place
Figure 7 i! ! 5 Figure 7 Figure 7 Figure 27 Figure 7 Voluntary Procedure Amendment 1, Indication of Case Showa! Patent Application No. 1 367 ≠ No. 2,
Title of the invention: Electrolytic treatment device 3, relationship with the amended case Patent applicant location: ζ, 210 Nakanuma, Minamiashigara City, Kanagawa Prefecture (406
) 2537 Table Target of amendment Drawing 5, contents of amendment (1) Figure 7 of the drawings will be replaced with the attached one.

Claims (3)

[Claims] (1) A soft start zone f where a low current density process is performed at the inlet portion of the metal web in an electrolytic bath where a metal web is subjected to continuous electrolytic etching treatment using an alternating waveform current:
An electrolytic treatment device characterized in that: (2) The electrolytic treatment apparatus according to claim 1, wherein the soft start zone comprises an electrode and a resistor or a thyristor. (3) A patent characterized in that the electrode of the soft start zone is notched diagonally so that the length of the surface facing the metal web is shortened, and the notched surface is arranged so as to be in direct contact with the electrolyte. An electrolytic treatment apparatus according to claim 1.