JPH04191383A - Etching method and deivce for roll - Google Patents

Abstract

PURPOSE:To improve both of an etching rate and etching factor by the extremely simple method by spray coating the surface of a roll with an etching liquid while rotating the roll in such a manner that centrifugal force of a specific value or above acts. CONSTITUTION:The etching liquid is sprayed by a spray nozzle 2 onto the surface of the roll 1 and the nozzle 2 is repetitively moved back and forth in the direction parallel with the length of the roll body by a traversing device 3 via a spray nozzle fixture 5. The roll 1 is supported by a driving device 4 contg. high-speed bearings and the roll is rotated around its axis in such a manner that centrifugal force >=-5g (g is the acceleration of gravity) acts on the roll surface. The centrifugal etching is executed with the small rotating device by this method without requiring a large immersion container. Both of the etching rate and the etching factor are thus improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a roll etching method and apparatus for forming countless irregularities as a precise pattern on the surface of a rolling roll.

[Prior Art] Generally known methods for etching a roll include immersing the roll in a container filled with an etching solution and spraying the etching solution onto the roll.

As an example of the immersion method, Japanese Patent Laid-Open No. 1-283389 discloses a method in which only the body of the roll 1 is immersed in an etching solution 6 filled in a shallow dish and rotated, as shown in FIG. An example of a spray coating method is JP-A-6
Japanese Patent No. 0-239753 discloses a method of spraying an etching liquid onto the roll surface from a plurality of nozzles while slowly rotating the roll, as shown in FIG. 3 or 4.

The method of roughening the surface by etching has been conventionally used. For example, as proposed in Japanese Patent Publication No. 42-9452 and Japanese Patent Publication No. 44-28968, a pattern is formed on the roll surface by electrolytic etching. There is a technology to do this.

This technique involves removing oil and fat stains from the surface of one roll, applying etching resist, drying this, and then forming a film with a predetermined pattern consisting of transparent parts and black parts. A patterned roll is manufactured by wrapping the above-mentioned roll in three layers, exposing it to light, and then developing, etching, and removing the resist.

Furthermore, as another method proposed in JP-A-2-175882, a resin film is formed by applying a corrosion-resistant resin liquid mixed with a light absorber, and a Q-switched YAG laser is used to form a resin film. There is a method of removing a part of the film by evaporation, then spraying an etching liquid onto the roll surface, and then peeling off the resin film to impart a pattern to the roll surface.

[Problem to be Solved by the Invention 1] The two conventional etching methods described above have the following problems.

■ Etching rate (etching speed) is small (
Etching takes time.

■ Because etching progresses in a relatively uniform direction, the fifth
The etch factor (etching depth d/undercut C) shown in the figure is unlikely to be 2 or more as an actual value.

FIG. 5 is an explanatory view showing an example in which a mask 8 is placed over a workpiece 7 to perform etching.

As a countermeasure to this problem, a technique called "centrifugal force etching" is known. For example, "The theory and technical trends of Taki style etching"
(Satoshi Sato - Practical surface technology vol. 135, No. 11
．． 1988 P2-P10), the workpiece 7 is immersed in a container 6 filled with an etching solution as shown in FIG. A rotation 12 about the axis ]l creates a negative gravitational field on the etched surface. In this gravitational field, a large gravitational difference is generated for a slight difference in the density of the etching liquid before and after the chemical reaction, so that the convection of the etching liquid in the depth direction is enhanced. Accordingly, the etching rate improves and the etch factor increases.

The disadvantage of this method is that the entire container 6 containing the etching solution in which the workpiece is immersed must be rotated at high speed, so if the workpiece is large, the entire apparatus including the container becomes very large. It is.

The present invention provides an extremely simple method that does not require an immersion container when centrifugal force etching is applied to a cylindrical workpiece.

[Means for Solving the Problems 1] In order to solve the above-mentioned problems, the present invention provides that, in imparting unevenness to the surface of a metal roll by etching, while applying an etching liquid to the roll surface, 5 g of etching is applied to the roll surface.
This is a roll etching method characterized by rotating the roll around the roll axis so that a centrifugal force of more than (g is the acceleration of gravity) acts.

The apparatus of the present invention that can suitably carry out this method includes a coating machine for applying etching liquid to the roll surface, a traverse device for moving the coating machine in the longitudinal direction of the roll, and a coating machine for moving the coating machine in the longitudinal direction of the roll. It is characterized by comprising a drive device that rotates the roll around an axis and a control device that controls the roll to a predetermined rotation speed.

[Effect] The method and apparatus of the present invention have the following effects.

(1) Since the etching solution is spray applied to the roll,
Does not require large soaking containers.

(2) Since only the rolls are rotated to apply centrifugal force, the rotating device may be smaller than in the case where the entire container is rotated.

(3) The negative gravitational field (centrifugal force) generated on the roll surface is set to a value of 5 g or more in absolute value based on the experimental results shown in FIG. FIG. 7 shows the relationship between roll rotation speed and etching factor.

The negative gravity (centrifugal force) generated on the roll surface is proportional to the roll rotation speed. A good result is obtained in that the etch factor increases as the centrifugal force increases. The centrifugal force is 5
The etching accuracy (E, F,) becomes 2 or more when it is more than g.

FIG. 7 shows data obtained by centrifugally etching a cast iron roll having an outer diameter of 150 mm and a body length of 200 mm using the apparatus shown in FIG. 1 using a 41% by weight aqueous solution of ferric chloride as the etching liquid.

[Example] FIG. 1 shows an example apparatus of the present invention. Spray nozzle 2 serves as a coating machine that applies etching liquid to the surface of roll l.
and a fixture 5 that supports it are shown. An etching liquid tank, pump, piping, etc. (not shown) are included. This atomizer is moved in the axial direction of the roll 1 by a traverse device 3. a drive device 4 for rotating the roll 1;
A rotation control device 10 is provided.

A resin containing a light absorbing material is applied to the surface of a cast iron roll 1 (outer diameter 150 mm, body length 150 mm) to a thickness of 10 μm or less by spray coating.

The resin on the surface of this roll is processed into a desired pattern by controlling YAG laser light. In this case, the resin in the laser beam irradiated area evaporates and the metal surface of the roll is exposed.

By this method, the resin on the entire surface of the roll is processed into a desired pattern, and this roll 1 is set in the apparatus shown in FIG. This pretreatment can also be performed by a method using a mask film.

The surface (exposed metal part) of this roll 1 is coated with a ferric chloride solution (
Baume degree 45°) was applied as an etching liquid using spray nozzle 2, and centrifugal etching was performed using the apparatus shown in FIG. 1 by rotating roll 1.

The etching liquid is sprayed onto the roll surface by a spray nozzle 2. This nozzle is a two-fluid nozzle and uses air as the assist gas.

The air flow rate at this time was 30 Q/min. The spray angle was 90', and the distance from the nozzle tip to the roll surface was 50 mm. Furthermore, this nozzle 2 is connected to the 4
Reciprocating motion is repeated in a direction parallel to the roll body length at a speed of 80 mm/min.

The roll 1 is supported by a drive device 4 having a built-in bearing for high-speed rotation, and can control rotation from 0 to 200 rpm.

The results of centrifugal force etching using the apparatus shown in FIG. 1 are shown in FIGS. 8 and 9. This is a three-dimensional roughness profile diagram of the roll surface after etching.

As the centrifugal force increases, the surface becomes deeper and sharper. Note that the etching time at this time was 10 minutes.

[Effects of the Invention] In the present invention, a centrifugal force exceeding 5 g in absolute value acts on the roll surface (as the etching solution is sprayed while rotating the roll), so a large container for storing the etching solution and the roll is required. Centrifugal force etching is now possible without the need for

Both the etching rate and the etch factor become larger than when no centrifugal force is applied.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention; a) is a plan view; (a) is a plan view;
, b) is an elevational view, FIG. 2 is a perspective view showing a conventional immersion device, FIGS. 3 and 4 are explanatory diagrams showing the conventional spray coating method, and FIG. 5 is an explanatory diagram of the etch factor. Figure 6 is an explanatory diagram showing the conventional centrifugal force etching method, Figure 7 is a graph showing the relationship between centrifugal force and etching accuracy, and Figures 8 and 9 are three-dimensional roll surfaces showing the effect of centrifugal force. It is a profile diagram. 1... Roll 2... Spray nozzle 3... Traverse device 4... Drive device 5... Spray nozzle fixture 6... Etching liquid 7... Processing material 8... Mask 9. ...Material holder 10...Rotation control device 11...Axis 12...Rotation

Claims (1)

[Claims] 1. In imparting unevenness to the surface of a metal roll by etching, while applying an etching solution to the roll surface,
A method for etching a roll, comprising rotating the roll around a roll axis so that a centrifugal force of -5 g (g is acceleration of gravity) or more acts on the roll surface. 2. A coating machine that applies etching liquid to the roll surface, a traverse device that moves the coating machine in the longitudinal direction of the roll, and a drive device that rotates the roll around the roll axis.
A roll etching device comprising: a control device that controls the number of rotations of the roll.