JPH02305994A - Device for continuously coloring stainless steel sheet - Google Patents

Abstract

PURPOSE:To obtain a stabilized multicolor tone with high efficiency by selecting a specified AC electrolysis condition in an electrolytic cell and continuously coloring a stainless steel sheet at a specified rate. CONSTITUTION:The pretreated steel sheet 9 is introduced into an AC electrolytic coloring vessel 5 provided with plural conductor rolls 14 and the counter electrodes 17 corresponding to the conductor rolls, and AC electrolysis is carried out between the counter electrode 17 and the steel sheet 9 to color the steel sheet. In this case, the color tone of the colored stainless steel sheet 23 depends on the thickness of the film resulting from the electrolysis. When the steel sheet 9 is passed through the vessel 5 at the fixed speed and the counter electrodes 17 are arranged at regular intervals with the same electrolytic capability, the color tone is controlled by the electrolyzing time. Accordingly, when the coloration in red, green, etc., is selected, the color is selected by selecting the number of current applications to the conductor roll 14 and counter electrode to control the electrolyzing time.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a continuous coloring apparatus for stainless steel sheets whose main use is as building materials.

<Prior Art> In recent years, the demand for stainless steel sheets as building materials has increased, and development of colored stainless steel sheets is progressing, particularly from the standpoint of design.

Colored stainless steel sheets have an extremely thin spinel-type oxide film on their surface, and appear colored due to the interference of light between the outer surface of this film and the base metal, and the color tone depends on the film thickness. As the color increases, the color changes from black to blue to gold to red to green.

A method and apparatus for manufacturing a colored stainless steel sheet by alternating current electrolysis have been previously filed by the present applicant, and are disclosed in, for example, Japanese Patent Laid-Open No. 61-127899 and Japanese Patent Laid-Open No. 62-103395.

<Problems to be Solved by the Invention> However, since the above method and apparatus color a stainless steel plate by setting alternating current electrolysis conditions corresponding to the color tone to be colored, the desired color tone may not be changed. In this case, it is necessary to change the corresponding alternating current electrolytic conditions each time, and there is a problem in that the operation of the coloring device must be stopped to set the predetermined electrolytic conditions.

On the other hand, as a method of coloring a stainless steel plate by fixing the electrolytic conditions in the coloring tank and controlling the color tone by measuring the potential difference with respect to the surface potential of the stainless steel plate immersed in the coloring tank, for example, JP-A-56 This method is disclosed in Japanese Patent No. 29677, but since two stainless steel plates must be stacked and immersed in a coloring tank, there are problems in that continuous production is not possible and a stable color tone cannot be obtained. there were.

The present invention is capable of coloring a stainless steel plate continuously at a predetermined speed by selecting predetermined alternating current electrolysis conditions in an electrolytic cell, thereby obtaining a variety of stable color tones with high efficiency. The purpose is to provide a continuous coloring device for stainless steel sheets.

<Means for Solving the Problems> In order to achieve the above object, the present invention provides pretreatment equipment for degreasing, pickling, and cleaning, and an alternating current electrolytic coloring device for coloring and hardening. In a continuous coloring apparatus for stainless steel sheets, which is connected to a post-processing apparatus for cleaning and drying colored stainless steel, a plurality of conductor rolls and corresponding counter electrodes are provided in the alternating current electrolytic coloring apparatus to achieve a predetermined color tone. Provided is a continuous coloring device for stainless steel sheets, characterized in that the number of conductor rolls and counter electrodes required for coloring can be appropriately selected and energized, and the time for receiving alternating electrolytic action can be selected. be done.

The present invention will be explained in more detail below.

FIG. 1 shows an example of the line apparatus of the present invention for coloring stainless steel plates.

In the continuous coloring apparatus for stainless steel sheets of the present invention, pre-treatment is performed if degreasing → dry cleaning 2 - pickling tank 3 - dry cleaning 4! 4
After that, alternating current electrolysis 4, which performs coloring and hardening in one liquid and one process.
i! 5 is installed, and then a hot water washing tank 6, a drying device 7, and a drying device 8 for post-processing are installed. Pairs of seal rolls 10 are arranged on both sides of each of the six tanks so that the stainless steel plate 9 can pass horizontally, that is, the pass line is horizontal. , 11 is a guide roll.

Pairs of electrolytic cell seal rolls 12 and 13 are provided on both sides of the alternating current electrolytic cell 5, respectively, to prevent wetting of the electrolytic solution and to allow the stainless steel plate 9 to pass through. The alternating current electrolytic cell 5 has a conductor roll 14 serving as one electrode.
A large number of electrolytic cell seal rolls are installed in parallel, and a pair of electrolytic cell seal rolls is 12°1.
A horizontal pass line for the stainless steel plate 9 is formed at the same height as the lower roll 3. A plurality of conductor rolls 14 are disposed substantially perpendicularly to the horizontal pass line, and a counter electrode 17 is disposed at a certain distance from the conductor rolls 14, respectively,
The rectifier 15 allows current to be applied to each pair between the conductor roll 14 and the counter electrode 17, and electrolysis is performed.

This configuration is achieved by appropriately selecting the number of energizations between the conductor roll and the counter electrode present in the electrolytic treatment tank.
That is, this is to enable selection of the time period during which the steel plate is subjected to electrolytic action in the electrolytic solution. For example, if you want to color the electrolytic cell blue, you can apply current between the conductor roll and the counter electrode up to the 5th electrode from the electrolytic cell's population side, and if you want to color it gold, you can apply the current up to the 10th electrode, without changing the electrolytic conditions. can be changed.

A color identification sensor 18 is installed on the outlet side of the alternating current electrolytic cell, and this is connected to the electrolytic condition control combiator 19 to control the color tone of the steel plate coloring, in order to produce stable colored steel plates. suitable. Further, it is also preferable to provide a chromic acid regeneration tank 20 and a chromic acid waste liquid treatment facility 21 as auxiliary devices in order to efficiently maintain a continuous line.

Function> The continuous coloring apparatus for stainless steel sheets according to the present invention is basically constructed as follows, and its function will be explained next.

The stainless steel plate 9 is inserted into the degreasing tank 1 (alkaline bath) from the depiler 22 through the inlet side of the conveyor A, where it is cleaned of oil and other dirt adhering to its surface, washed in the hot water washing tank 2, and then pickled. (for example, a sulfuric acid bath) 4!13 to form a uniform passive film on the surface, and after washing in a hot water bath 4, it is led to an alternating current electrolytic bath 5. This electrode has a counter electrode 17, and alternating current electrolysis is performed between this electrode and the stainless steel plate 9, and the plate is colored and leaves the electrolytic cell 5.

At this time, a color identification sensor 18 is installed above the colored stainless steel plate 23 at the outlet, a part of the solution on the colored stainless steel plate is blown off with compressed air, and the color tone is measured in this part. Data (color display is J
IS Z 8730 (preferably using color difference) is input into the control computer 19, and if the color difference exceeds the preset limit, the electrolytic conditions (current density i of anodic electrolysis and cathodic electrolysis and each electrolysis time t) are input into the control computer 19. It is preferable in terms of color tone control to control the coloring process by feeding back the electrolysis cycle number N, bath temperature, etc.). At this time, it is not necessarily necessary to change the sheet passing speed.

In this way, the stainless steel plate 23, which has been finished in the expected color tone, is completely washed to remove the solution on its surface in two subsequent hot water washing tanks 6. can be dried. Thereafter, they are loaded onto a piler 25, preferably with a protective sheet 24 inserted between them.

Here, since the color tone of the colored stainless steel plate is determined by the thickness of the film obtained by electrolytic treatment, the stainless steel plate is passed through the electrolytic tank at a constant speed, and each counter electrode is adjusted at equal intervals with the same electrolytic capacity. Sometimes the color tone can be controlled by the electrolysis time in the electrolytic cell.

In the present invention, the electrolysis time is selected by appropriately selecting the number of conductor rolls and counter electrodes to be energized in the electrolytic cell.

For example, under predetermined electrolytic conditions, the colors to be colored can be selected with a simple operation, such as 5 pieces to be colored blue and 10 pieces to be colored gold.

Moreover, when it is desired to select the coloring of red, edges, etc., it is sufficient to select the number of energizations of the conductor roll and the opposite electrode, respectively.

<Example> The present invention will be specifically described below based on Examples.

(Example 1) After pretreatment as usual, alternating current electrolysis 4! ! As a solution of 5, the ingredients are 250 g/11 chromic anhydride + 500
g/It sulfuric acid at a temperature of 60°C ± 2°C, and the conditions input into the control computer, namely, anode current density 0.5A/dm', cathode current density 0. A SO5304B^ (bright annealing) treated steel plate was colored using the apparatus shown in Fig. 1 at a passing rate of 10 am/min with anode and cathode electrolysis times of 10 seconds each. The interval was 20 cm, and 10 counter electrodes at the front in the electrolytic cell 5 were used.

As a result, the obtained colored stainless steel sheet exhibited a golden color tone.

Next, the five rectifiers in front were energized without changing the electrolytic treatment conditions, and the same steel plate as above was colored.

As a result, the obtained colored stainless steel sheet exhibited a blue tone.

The above 2fi type electrolytic treatment was repeatedly carried out, and gold-colored, blue-colored stainless steel plates with good reproducibility were obtained.

<Effects of the Invention> According to the present invention, which is configured as described above, it is possible to produce a variety of colors while keeping the alternating current electrolysis conditions in the electrolytic cell constant without selecting and changing the predetermined conditions. A continuous coloring apparatus for stainless steel sheets is obtained, which can continuously produce colored stainless steel sheets with high efficiency using the same equipment, and can provide stable color tones.

[Brief explanation of drawings]

FIG. 1 is a diagrammatic cross-sectional view of a continuous coloring apparatus for stainless steel sheets according to the present invention. Explanation of symbols 1... Degreasing tank, 2... Hot water washing tank, 3... Pickling tank, 4... Hot water washing tank, 5... Alternating current electrolytic cell, 6.7... Water washing Tank, 8... Dryer, 9... Stainless steel plate, 10... Seal roll, 11... Guide roll, 12.13... Electrolytic tank seal roll, 14... Conductor roll, 15 ... Rectifier, 17... Counter electrode, 1B... Color identification sensor, 19... Control computer, 20... Chromic acid regeneration tank, 21... Chromic acid waste liquid treatment equipment, 22... Depiler , 23... Colored stainless steel plate, 24... Protective sheet, 25... Piler

Claims (1)

[Claims] (1) Stainless steel made by installing pre-treatment equipment for degreasing, pickling, and cleaning, alternating current electrolytic coloring equipment for coloring and hardening, and post-treatment equipment for cleaning and drying colored stainless steel. In a continuous coloring apparatus for steel sheets, a plurality of conductor rolls and corresponding counter electrodes are provided in the alternating current electrolytic coloring apparatus, and the number of conductor rolls and counter electrodes necessary for coloring a predetermined color tone is appropriately selected and energized. 1. A continuous coloring apparatus for stainless steel sheets, characterized in that the apparatus is configured such that the time for receiving alternating electrolytic action can be selected.