JPS6028911B2 - Scale construction method for stainless steel length measuring instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing a scale for a stainless steel ruler.

The conventional method for making scales on metal length gauges is to apply a photosensitive resin to a metal surface made of stainless steel, dry it to form a film, and then apply a negative film with precision scales prepared in advance to the photosensitive resin. The first step is to adhere to the resin film, irradiate it with ultraviolet rays to expose a part of the resin film, and then wash away the non-sensitized part in a developer to expose the metal surface of that part. This metal part is etched with a metal etching agent to form a concave shape, and then the concave scale part is blackened by black chrome plating to form the scale of the proximal device.

That is, in the conventional method, black chrome plating was an essential step. However, plating using chromium is problematic from the standpoint of pollution, and equipment for detoxifying wastewater requires a huge amount of expense.

Furthermore, even though the workers who carry out the black chrome plating process are equipped with ventilation devices and mist removal devices, if they work for a long period of time, it is difficult to avoid health damage caused by hexavalent chromium. Furthermore, black chrome plating has the disadvantages of not only rapid corrosion of the equipment and extremely short depreciation period but also a large amount of electricity consumption, which is economically disadvantageous.
The inventor of the present invention has conducted extensive research in an effort to devise a method for creating a scale for a metal length gauge that would solve the problems associated with black chrome plating, and as a result, has developed a method for depositing a solid and homogeneous copper coating on the surface of stainless steel. , discovered a method of blackening the copper coating, and found that this solved the above problems.

In the present invention, first, stainless steel is prepared with a pH of about 0.1 to 1.0 mol/containing copper ions and acetate ions of about 2.
．． A copper coating is deposited on the surface of stainless steel by contacting it with a copper precipitation solution having a molecular weight of 8 to 3.8 at room temperature for about 5 seconds to 12 seconds.

It is known that a copper film can be formed on the surface of iron by contacting iron with an acidic solution containing copper ions, for example, according to the following formula: CuS04+Fe→Cu+FeS04.

However, when stainless steel is used instead of iron, no copper is deposited at all. As a result of research on this point, the inventor found that
We focused on the fact that the reason why copper does not precipitate on stainless steel is that the chromium contained in stainless steel forms a passive film that is strong in the copper precipitation solution. Surprisingly, this passive film is formed in a certain pH range, i.e.
= about 2.8~3. It has been found that instantaneous failure can occur only at about 3.0 to 3.3 mounds, and at the same time copper deposition can occur quickly in this pressing area. Here, stainless steel includes all types of stainless steel, such as 13
% chromium steel, 18% chromium steel, and 18-8 nickel-chromium steel. The pH of the copper precipitation solution is about 2.8-3. The weight should be adjusted to about 3.0-3.3.

pH adjustment is carried out using an inorganic or organic acid. The appropriate copper ion concentration in the copper depositing solution is related to the contact time, temperature, desired film thickness, etc.

Operations that involve contact over a long period of time are undesirable in terms of the process. On the other hand, a film obtained under conditions such as obtaining a film of 0.2 degrees in a very short period of time, for example, 2 seconds, is not preferred because it is not uniform and porous. In general, it has been found that the copper ion concentration is preferably in the range of about 0.1 to 1.0 mol/, particularly about 0.4 to 0.6 mol/. Copper ions are added to the liquid as copper salts, such as copper acetate chloride.

The contacting temperature is preferably room temperature from the viewpoint of ease of operation and economy, and a good copper coating is deposited at room temperature, for example, 20 to 35 qo. The contact time is determined by the desired coating thickness, but to obtain a coating thickness of 0.2 mm to 4 mm, a contact time of at least about 5 seconds and at most about 12 mm will produce an excellent coating. I found out that I can get it. Furthermore, it has been found that when acetic acid is present in the precipitating solution, a more uniform film is obtained instead of being porous.

Acetic acid can be added to the liquid as an acid for pH adjustment or as an acetic acid. Acetate ion concentration is 0.1-0
．． Preferably it is present in an amount of 8 mol/sleeve, preferably 0.3 to 0.5 mol/sleeve. While the acetate ion makes the film more uniform, it also works to slow down the rate of film formation. In the presence of acetate ions, a uniform coating of 0.2 to 2 sides is deposited in 20 to 90 seconds, but in the absence of acetate ions, it is deposited in 5 to 5 silica sand. The most desirable copper precipitation conditions are acetic acid steel 50-70 g/chlorinated steel 15-20 g/acetic acid
8-14'/Yuu hydrochloric acid
Using the precipitation solution of 3-4'/〆, the solution temperature is 25
~3500 and 5 to 5 sand-to-sand contacts.

By carrying out the simple method described above, it has become possible to deposit a uniform and robust copper coating on the surface of stainless steel without using complicated equipment.

Next, a black coating is formed on the stainless steel surface by bringing the steel coating into contact with a blackening solution containing a selenium (W) compound. That is, in the present invention, the steel coating is made of selenium (W).
The present invention relates to a method of forming a black film on a stainless steel surface by contacting it with a blackening solution containing a compound. Examples of the tetravalent selenium compound include selenite and salts of selenite, such as sodium and potassium salts.

The concentration of selenium (W) compound is about 0.00 for tetravalent selenium.
2 to 0.05 molar, preferably about 0.005 to 0.05 molar.
Select so that the amount is 0.2 mol/〆. It is thought that blackening occurs when selenium binds to copper. The temperature is room temperature, for example 2
0 to 35 qo is advantageous. Contact time is approximately 30-18
Inkstone sand is sufficient. Furthermore, the inventors have discovered that blackening progresses more quickly when copper ions are added to the blackening solution. The concentration of copper ions is preferably about 0.02 to 0.2 moles/range. Furthermore, by adding molybdic acid or a salt thereof to the blackening solution, a black film with an even greater blackness can be obtained. The amount added is preferably in the range of 0.02 to 5 g' of ammonium molybdate. The most preferred conditions for blackening are: selenite (Se03) 1.0-2 g/sulfuric acid salt 5.0-20.0 g nosoacetic acid salt 0.5-2 g'comolybdic acid 0.5-2 g of ammonium/blackening solution is used for contacting for 60-12 stages at a temperature of 25-35 qo.

As an embodiment of the present invention as described above, a photosensitive resin coating is formed on the surface of stainless steel, a negative film with precision scales corresponding to the scale of the long film is adhered thereto, and the unexposed areas irradiated with ultraviolet rays are washed away. , with stainless steel that has some metal surfaces exposed and some metal surfaces covered,
By subjecting the steel to the above-described steel precipitation method and subsequently forming a black film, a durable and beautiful elongated device with black scales can be obtained.

Further, it is possible to produce a product by depositing copper on the surface of a stainless steel product for decorative purposes or by blackening it. Hereinafter, the present invention will be described in detail with reference to Examples.

Reference Example 3 A 13% chromium steel plate of 30 arcs was immersed in a copper precipitation solution (3000) having the following composition for 5 hours.

Copper acetate 50 g/copper chloride
15 g/chloride acid
3'/Yuu vinegar acid
The chrome steel plate was removed from the solution and washed.

A nearly non-porous deposited film of approximately 21 molar thickness was obtained. Example 3 A 18% chromium steel plate of 3 x 30 mm, covered with a photosensitive resin except for the exposed steel surface in the form of slits, was mixed with 3 layers (3000) of copper depositing solution having the following composition and 9 minutes of rat sand. It was soaked for a while.

Chloride steel 30 g/Acetate steel
25 g/soybean acid
An extremely uniform, completely non-porous copper deposit film having a thickness of about 1 µm was obtained in the slit portion of the resin.

Claims (1)

[Claims] 1. In the scale construction method of a stainless steel length measuring device, the stainless steel surface of the exposed concave scale portion is approximately 0.1 to 1.0
A copper precipitation solution containing copper ions of mol/l and acetate ions with a pH of about 2.8 to 3.8 is added at room temperature to about 5 to 120
Depositing a copper film on the stainless steel surface by contacting for seconds, and then forming a black film on the stainless steel surface by contacting this with a blackening solution containing a selenium (IV) compound and molybdate ions. Features a stainless steel method. 2. The method according to claim 1, wherein the blackening solution contains copper ions.