JPH07115046B2 - Patterned metal plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention transfers a dot matrix of minute pits formed by irradiation of a laser beam to a roll such as a rolling mill and recognizes it as a certain pattern in appearance. The present invention relates to a patterned metal plate having a pattern.

<Prior Art and Problems Thereof> In general, various coatings are applied to the surface of a steel sheet for the purpose of improving the appearance and the like. However, stainless steel, tin-free steel plate, transparent lacquer-finished steel plate, etc. are used with the gloss and roughness of the steel plate surface unchanged. Therefore, improvement of the surface beauty of these steel sheets is very important.

However, at present, as a surface processing technology aimed at improving the surface appearance, etc., a method of processing the roll surface by chemical corrosion or mechanical processing and transferring the pattern to the steel plate surface using the roll (embossing method )It has been known. In particular, as the method applied to mass production, only the former method of chemically corroding the roll is practically used at present.

Many such embossing techniques have been disclosed including Japanese Patent Laid-Open Nos. 51-52937 and 51-52938.

These are so-called photo-etching techniques and are not only expensive, but also have a major drawback that the roughness is not constant (the surface irregularities are too large).

However, for patterning by chemical corrosion, (1) only large patterns are possible and fine processing is difficult, (2) various patterns are difficult to produce, and work efficiency is extremely low, (3) ) It was not suitable for general use, etc.

In particular, the conventional techniques have been of no use for performing beautiful patterning and patterning while keeping the roughness of the steel plate constant.

<Objects of the Invention> An object of the present invention is to solve the above-mentioned problems of the prior art, to intermittently irradiate a laser beam, and to collect a fine pit of a certain shape on a roll surface used in rolling, that is, a dot matrix. A pattern metal plate on which a pattern consisting of, and rolled down by the roll, to which the pattern has been transferred, in particular, metal is formed by changing the unevenness of the minute pits, the pit diameter, the pit distance and the overlapping state of the minute pits. An object of the present invention is to provide a patterned metal plate having an accurate and clear pattern which is recognized as a certain pattern in appearance when it is transferred to the plate surface and which is composed of a dot matrix.

<Structure of the Invention> According to the present invention, minute pits formed by a laser are engraved on the surface of a metal plate in a state where the minute pit irregularities, the pit diameter and the distance between the pits are changed, and the pits are overlapped. A patterned metal plate is provided.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The metal plate used in the present invention is preferably a steel plate manufactured through a rolling process, and any steel plate may be used, and examples thereof include a cold rolled steel plate and a surface-treated steel plate. In particular, stainless steel and tin-free steel plate which are unpainted steel plates are preferable. However, when the coating is thinner than the unevenness of the pattern engraved on the surface of the steel sheet, the pattern on the surface of the steel sheet can be raised after the thin coating treatment, and therefore the coating treatment is not hindered. Further, other metal plates such as steel plate, aluminum plate or various plated steel plates may be used.

In the following description, a steel plate will be described as a typical metal plate.

The pattern engraved on the surface of the steel sheet of the present invention is a state in which an aggregate of minute pits formed on a roll or the like by irradiation with a laser beam changes the unevenness of the minute pits, the pit diameter, and the pit interval, and the minute pits. Any pattern that is drawn as one pattern consisting of dot matrix in the overlapping state, can be transferred or stamped on the surface of the steel sheet by reduction by rolling etc., and is recognized as a certain pattern in appearance However, it may be any pattern, mark, picture, figure, character, grayscale image, or photograph.

The above-mentioned pattern is obtained as a dot matrix recognized as a certain pattern, that is, an assembly of minute convex portions 2 shown in FIG. 1b formed by imprinting the minute pits 10 shown in FIG. 1a on the surface of the steel plate 1. It is what is done. The shape of the minute convex portion 2 shown in FIG. 1b can be variously changed according to the desired pattern, but it is a transfer of the shape of the minute pit 10 shown in FIG. 1a. Depending on the situation, the fine pits 10 may be completely transferred or a part thereof may be transferred. The minute pit 10 will be described below.

As shown in FIG. 1a, the minute pits 10 melt the roll base metal by irradiating the surface of the roll 12 with the laser beam 14 to form a hole-shaped or circular depression, and the peripheral portion of the depression rises. , Formed in a crater shape. The size, depth and hole shape or the degree of swelling of the minute pits 10 can be changed by changing the intensity of the laser beam 14, irradiation time, and conditions such as blowing gas such as oxygen during laser beam irradiation. Can be made.

However, the size of the small pit 10 has a maximum diameter of 1 mm.
The following is practically preferable. More preferably 50-50
0 μm is preferable. The reason for this is that if the diameter of the minute pits 10 is larger than 1 mm, the processing of the steel sheet by the rolls 12 becomes non-uniform and processing strain is applied even to the inside of the steel sheet, and the material is likely to deteriorate. Further, if it deviates from the above range, it is not preferable from the viewpoint of aesthetics and accuracy.

In order to transfer a predetermined pattern to the steel plate to form a patterned steel plate, in order to form the aggregate of the minute pits on the roll surface so as to obtain the desired pattern, an intermittent laser beam generator and position control drive are used. The device is preferably controlled by a computer. The intermittent laser beam generator controls the laser beam irradiation interval and may have a chopper for cutting the laser beam, and the chopper may be electrical or mechanical.

The minute pits are engraved on the roll by the laser beam to form the pattern. The unevenness, the pit diameter, and the pit interval are changed on the minute pits.
Alternatively, it is necessary to overlap and change the minute pits. The specific patterning method will be described below.

i) As shown in FIG. 1c, the opening / closing timing of the laser beam cutting chopper 16 for controlling the laser beam irradiation interval is changed to shift the laser beam irradiation position while rotating the surface of the roll 12 at a constant rotation.

ii) The output of the laser beam or the focus on the roll surface is changed, and the irradiation on the entire roll surface is divided into a plurality of times to form patterns in which the irregularities of the small pits, the pit diameter, and the pit spacing are changed.

iii) Using a plurality of laser irradiation devices set under the respective conditions, irradiation on the entire surface of the roll is completed once.

As described above, the roll is patterned by the fine pits, but when the roll is the final rolling step, that is, in the ordinary cold-rolled steel sheet, in the temper rolling step after annealing, and when temper rolling is omitted, Is preferably used as a reduction roll in the final stand of a cold rolling mill, which allows a pattern to be easily transferred to the steel sheet.

Further, in order to transfer the pattern drawn on the roll to the surface of the steel sheet beautifully and accurately, it is necessary to have a sufficient reduction ratio, but the skin pass reduction ratio is preferably 0.3% or more.

The reason for this is that if the rolling reduction is less than 0.3%, a sufficient transfer rate cannot be obtained.

The roll is not limited to the case where the roll surface is bright, but may be a dull surface, or may be dull processed after forming a pattern of minute pits by laser beam irradiation. Furthermore, it does not impede temper rolling under a light reduction for the purpose of surface adjustment or control of mechanical properties within a range where the pattern is not erased after being transferred by a roll.

<Examples> Hereinafter, the present invention will be specifically described with reference to Examples.

Installed a chopper (an electric one is used in this case) to interrupt the laser beam to a carbon dioxide gas laser with an output of 2.5 Kw, and control the position on the temper rolling roll (SUJ 2)
Marks were drawn by changing the size of the micro pits) while controlling the output.

Using the roll for temper rolling on which the mark is drawn, the reduction rate
When a cold-rolled steel sheet (JIS, SPCC) having a thickness of 0.8% and a thickness of 0.8 mm was temper-rolled, marks schematically shown in FIG. 2 as an enlarged view were formed on the surface of the steel sheet. When seen with the naked eye, small marks were clearly visible.

FIG. 3 shows an example in which the pit density is changed.

The obtained pattern had a beauty and precision that was incomparable to the conventional roll patterning method using chemical corrosion.

It has been confirmed that it is possible to transfer any pattern such as pictures and letters by the same principle.

Furthermore, it was confirmed that transfer of photographs etc. is possible in principle.

<Effects of the Invention> According to the present invention, since an aggregate of minute bits formed by irradiation of a laser beam, that is, a dot matrix is transferred, the appearance of the dot matrix formed on the surface of a metal plate is improved. A pattern recognized as a certain pattern can be accurate and clear.

Further, according to the present invention, in the aggregate of the minute pits, the unevenness of the minute pits, the pit diameter, the distance between the pits can be changed, and the minute pits can be put in an overlapping state. A complex metal plate having a pattern such as a picture or a photograph can be used as a tint image or a pattern, and the patterned metal plate can be transferred.

Further, according to the present invention, since a new pattern can be drawn on the surface of the metal plate, the appearance of the metal plate can be dramatically improved, and thus a metal plate with high added value can be obtained.

[Brief description of drawings]

FIG. 1a is a schematic cross-sectional view of minute pits formed on the roll surface by laser beam irradiation. FIG. 1b is a schematic sectional view of a minute convex portion formed on a steel plate by transferring the minute pit of FIG. 1a. FIG. 1c is a schematic view showing a method of patterning a roll by irradiation with a laser beam. FIG. 2 is an example of a schematic enlarged view of a mark in which a pattern drawn by changing the size of a minute pit is transferred. FIG. 3 is an example of a schematic enlarged view of a mark in which a pattern drawn by changing the density of minute pits is transferred. Explanation of symbols 1 ... Steel plate, 2 ... Small convex portion, 10 ... Small pit, 12 ... Roll, 14 ... Laser beam, 16 ... Chopper

Claims (1)

[Claims] 1. A patterned metal plate in which fine pits formed by a laser are engraved on the surface of a metal plate in a state in which the fine pit irregularities, the diameter of the pits and the distance between the pits are changed and the pits overlap each other.