JPH01316497A - Device for producing colored stainless steel sheet - Google Patents

Abstract

PURPOSE:To produce the title colored stainless steel sheet having a colorful tone and excellent wear resistance with good reproducibility by providing a separate cathodic electrolytic device between an AC pigmentation device and a post-treating device at the time of producing a colored stainless steel sheet. CONSTITUTION:A stainless steel sheet 1 is passed through a degreasing tank 3, a hot-water washing tank 4, a pickling tank 5, and a hot-water washing tank 6, and pretreated. The sheet 1 is then introduced into an AC electrolytic cell 8 through a conductor roll 7. AC electrolysis is carried out between a counter electrode 9 and the sheet 1 in the cell 8 to color the sheet 1, the colored tone is controlled by a color discriminating sensor 11 and a control computer 12 at the outlet, and the sheet 1 is introduced into a cathodic electrolytic cell 14. Cathodic electrolysis is carried out between a counter electrode 15 and the sheet 1 in the cell 14 to harden the sheet 1. The sheet 1 is then post-treated through hot-water washing tanks 16 and 17 and a drier 8, and wound on a winder 20. By this method, the relatively porous colored film formed by the AC electrolysis is sealed and reinforced by cathodic electrolysis, and a colored stainless steel sheet capable of withstanding severe environment is obtained with good reproducibility.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an apparatus for producing colored 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, especially 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 an 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 Nos. 127899-1989 and 103395-1980.

<Problem to be solved by the invention> However, the above method and apparatus perform "coloring" and "hardening" in one step with one liquid, and the main use of chemically colored stainless steel sheets is for building materials. Therefore, depending on the place of use, even higher hardness is required, which limits the range of color tones and abrasion resistance.゛ Also, there were problems with weather resistance in harsh environments.

An object of the present invention is to provide an apparatus for manufacturing a colored stainless steel sheet that has a wide variety of colors, is excellent in wear resistance, and can withstand harsh environments.

Means for Solving the Problems> In order to achieve the above objects, the present invention provides a pretreatment device for degreasing, pickling, and cleaning, and an alternating current electrolytic coloring device for coloring and hardening. , a colored stainless steel plate manufacturing apparatus which is connected with a post-treatment device for cleaning and drying the colored stainless steel plate, comprising a separate cathode electrolysis device between the alternating current electrolytic coloring device and the post-treatment device. An apparatus for manufacturing a colored stainless steel sheet is provided.

The present invention will be explained in more detail below.

Figure 1 shows the features of the present invention! Colored stainless steel strip (
(Steel plate) is a configuration diagram of a continuous coloring line.

Stainless steel f1 is uncoiled from the uncoiler 2, removed from the surface in a degreasing tank 3 (alkaline bath) to remove dirt such as oil attached to the surface, washed in a hot water washing tank 4, and then washed in a pickling (for example, nitric acid bath) tank 5. A uniform passive film is formed on the surface, washed in a hot water bath 6, passed through a conductor roll 7, and subjected to alternating current electrolysis 4! Guided by i8. This tank has a counter electrode 9, which performs alternating current electrolysis between this and the stainless steel strip 1, and exits from this electrolysis 418 colored.

At this time, a color identification sensor 11 is installed on the guide roll 10 at the outlet, and a part of the solution on the colored stainless steel strip 1 is blown off with compressed air, and the color tone is measured in this part. data (colors shown are JI)
If the color difference exceeds the preset color difference limit, input the electrolytic conditions (current density i of anodic electrolysis and cathodic electrolysis, and each electrolysis time) into the control computer 12. 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.

Subsequently, it passes through the conductor roll 13 and is led to the #electrode electrolytic cell 14 . This tank has a counter electrode 15, which performs cathodic electrolysis between the counter electrode 15 and the stainless steel strip 1, and leaves the electrolytic tank 14 after being hardened.

In this way, the finished stainless steel strip 1 with the expected color tone is thoroughly washed with the solution on the surface in two subsequent hot water washes, and then placed in a dryer outside the bath! The surface can be dried by hot air blown out from 8. Thereafter, it is preferably wound up by a winding machine 20 while inserting a protective sheet 19 therebetween.

Depending on the arrangement or operation of the counter electrodes 9 and 15 in the alternating current electrolytic cell 8 and the cathode electrolytic cell 14, it is possible to color the stainless steel wI band 1 on one side as well as on both sides. That is, when coloring both sides of the stainless steel strip 1, alternating current electrolysis 4 is applied.
! actuate the counter electrodes 9 on both sides of the stainless steel strip 1 within 8;
Next, it is sufficient to operate the counter electrodes 15 on both sides in the cathode electrolytic cell 14, and when coloring one side of the stainless steel MFL, alternating current electrolysis 1! Opposite electrode 9 on one side of stainless steel strip 1 in y8
is activated, and then one side of the counter electrode 15 is activated in the cathode electrolytic cell 14.
All you have to do is activate it.

In the present invention, since the cathode electrolytic cell 14 is provided after the alternating current electrolysis cell #R8i, which is completely separated from the alternating current electrolyzing cell #R8i, the influence of mutual current can be prevented.
It becomes possible to strictly control the electrolytic conditions in each electrolytic cell, making it possible to strengthen the oxide film more than before, and making it possible to develop a thicker color tone on the film. That is, after the coloring and hardening treatment, hardening treatment is further performed by cathodic electrolysis, so that the relatively porous colored film formed by alternating current electrolysis is strengthened in pore sealing by cathodic electrolysis. In addition to making it possible to create a thick film with a unique color tone that was almost impossible, it also has a sufficiently hardened film that provides sufficient protection even in harsh environments.

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

(Example 1) After pretreatment as usual, the components of the solution in the alternating current electrolytic cell 8 were (250 g/f1. chromic anhydride + 500 g
/u sulfuric acid) at a temperature of 60°C ± 2°C, and as the solution for the cathode electrolytic cell 14, the components were (250 g/J2 chromic anhydride + 500 g/1) as in the alternating current electrolytic cell 8.
1 sulfuric acid) at a temperature of 60°C ± 2°C, and for the alternating current electrolytic cell 8, the conditions input into the control computer were set: anode current density 0.5A/dm', cathode current density 0.1A/dm. ”, %・Cathode electrolysis time: 10 seconds each at a plate passing speed of 10 cm/min, and a cathode electrolysis tank of 14
For the case, the cathode current density is 0.8 A/dm” and the threading speed is 1.
A 5LIS304 BA (bright annealing) treated steel strip was colored and hardened using the apparatus shown in FIG. 1 at 0 cm/min. As a result, the obtained colored stainless steel strip exhibited a golden color tone, and the results of tests conducted on this steel strip were as follows.

(2) Abrasion resistance A wear resistance test was carried out by rubbing the surface of the colored film with chromium oxide abrasive paper using an abrasion resistance tester under the condition of a load of 500 g. Abrasion resistance was evaluated based on the number of times of abrasion with chromium oxide abrasive paper until the colored film was completely removed, and it was determined that the greater the number of abrasions, the better the abrasion resistance.

As a result, the improvement was approximately 1.2 times that of the conventional one-liquid, one-step process.

■Weather resistance 30% FeCILs at 30°C - After a 2-hour immersion test in 6H20, the corrosion rate was reduced to about 2/3 compared to the conventional 1-liquid 1-process.

■Uniformity of color tone: 0.1 compared to the conventional one-liquid, one-process color difference △EO02 or less
A score of 5 or less was obtained.

<Effects of the Invention> Since the present invention is configured as described above, a colored stainless steel sheet can be produced with good reproducibility, having a variety of color tones, excellent wear resistance, and being able to withstand harsh environments. A manufacturing device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a continuous coloring apparatus for stainless steel strips according to the present invention. Explanation of symbols 1... Stainless steel strip, 2... Uncoiler-1 3... Degreasing tank, 4... Hot water washing tank, 5... Pickling tank, 6... Hot water washing tank, 7 ... Conductor roll, 8... Alternating current electrolyzer, 9... Counter electrode, 10... Guide roll. DESCRIPTION OF SYMBOLS 11... Color identification sensor, 12... Control computer, 13... Conductor roll, 14... Cathode electrolytic cell, 15... Counter electrode, 16... Hot water washing tank, 17... Hot water Washing tank, 18... Dryer, 19... Protective sheet, 20... Winding machine

Claims (1)

[Claims] (1) Coloring consisting of a pre-treatment device that performs degreasing, pickling, and cleaning, an alternating current electrolytic coloring device that performs coloring and hardening, and a post-treatment device that cleans and dries the colored stainless steel sheet. An apparatus for producing a colored stainless steel plate, comprising: a separate cathode electrolysis device between the alternating current electrolytic coloring device and the post-treatment device.