JPS5864385A - Barrel polishing method using chemical polishing in combination - Google Patents

Abstract

PURPOSE:To polish the work of copper or a copper alloy uniformly, readily in a short time by subjecting the work to barrel polishing, by using a chemical polishing agent of a liquid mixture of monocarboxylic acid and hydrogen peroxide or the mixture added further with nitric acid. CONSTITUTION:A chemical polishing agent contg. 200-2g/l acetic acid as monocarboxylic acid and 150-1g/l hydrogen peroxide or contg. 200-1g/l formic acid and 250-2g/l hydrogen peroxide is suitable as a compd. for barrel polishing of the work of copper and a copper alloy. Further the speed of polishing can be increased by adding a small amt. of nitric acid. In the case of adding the nitric acid, it is adequate to contain the same at <=1.2mol ratio between the nitric acid and the acetic acid to the hydrogen peroxide within a 0.7-1.0 range of molar ratio between the acetic acid and the hydrogen peroxide, or at <=0.7mol ratio between the nitric acid and the formic acid to the hydrogen peroxide in a 0.3-0.5 range of molar ratio between the formic acid and the hydrogen perioxide.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a barrel polishing method that aims to use chemical polishing in combination with barrel polishing by adding a chemical polishing agent instead of water and compound that were conventionally added during barrel polishing. It is about law.

Conventionally, as one of the effective means for finishing the surface of various metal workpieces, rotation, centrifugal rotation, and rocking are used in a polishing tank filled with abrasive material, water, and compound (hereinafter collectively referred to as "mass") along with the workpiece. Alternatively, a barrel polishing method has been known in which a workpiece is polished by applying motion such as vibration to generate a relative motion between the workpiece and an abrasive material. For example, various barrel polishing methods such as the rotary type, centrifugal rotation type, rocking type, vibration type, reciprocating type, and gyro type have been developed and are now in practical use.

This barrel polishing method is called mass finishing, and its high processing efficiency has led to many abandoned buildings, but it is desired to further improve processing efficiency and improve the polishing of recesses and holes that are difficult to contact with abrasive materials. .

In addition, chemical polishing, in which workpieces are immersed in a bath containing specific acids, alkalis, or these salts to smooth them, does not require special equipment (it is relatively easy to polish workpieces with complex shapes evenly and in a short time). As a chemical polishing agent for copper and copper alloys, a smoothing method of immersion in sulfuric acid or a mixed solution of nitric acid and hydrogen peroxide, such as Japanese Patent Publication Shojiq-6
03J, Special Public Shoda 3-274/, Special Public Sho 3J-32JJ
Although commercially available products such as CPB (Mitsubishi Gas Chemical Co., Ltd.) and Hyprite (Nippon Peroxide Co., Ltd. 1!L) are well-known, the surface condition and surface roughness of the workpiece There are limitations in the processing capacity of workpieces, the composition, concentration and temperature control of the polishing liquid that governs the metal dissolution reaction, and drainage treatment.In addition, compared to barrel polishing, large particles cannot be removed. There was a problem. In addition, the plate-shaped workpiece has such drawbacks that it is difficult to polish because it is densely layered, and the surface becomes rough.

However, the present invention corrects the drawbacks of conventional barrel polishing and chemical polishing by using a mixture of monocarboxylic acid and hydrogen peroxide or a chemical polishing agent with nitric acid added thereto as a compound for barrel polishing. The efficiency of the system has been dramatically improved, and its advantages are listed below.

■The polishing processing time can be shortened @The amount of wear of the abrasive material is reduced @The labor can be saved in part of the polishing process such as rough finishing, medium finishing, gloss finishing ■Prevention of deformation and distortion of the workpiece Able to achieve uniform polishing of fine parts, recesses, and holes that cannot be polished with a polishing stone ■ Has excellent smoothness and gloss ■ Improves smoothness and plating tightness after plating We have obtained a chemical polishing agent for ideal copper milling and copper alloy barrel polishing, which has led to the success of the barrel polishing method combined with chemical polishing. The explanation is as follows. As a barrel polishing machine, it can be used in any of the rotating, centrifugal rotating, rocking, vibrating, reciprocating, and gyroscopic types; Due to internal pressure build-up due to heat, it is desirable to install a degassing device in closed barrels. Addition of new liquid as the chemical polishing agent wears out, dispersion and removal of reaction heat, continuous and fully automatic loading and unloading of workpieces, and excellent glossy finish with no dents on workpieces. The open type vibrating barrel is the most suitable in various respects. The type of abrasive can be used for rough finishing, medium finishing, or gloss finishing, and it can be used for rough finishing, medium finishing, and gloss finishing.
Selected according to the purpose of polishing. When using the above-mentioned commercially available chemical polishing agents for barrel polishing, the large amount of hydrogen peroxide that contains a large amount of autolytic decomposition oxygen is extremely high (therefore, the reaction heat is also large (it becomes difficult to control the temperature of the mass, and the polishing speed decreases). Although the surface of the workpiece is large, the surface of the workpiece becomes rough, mass-produced polishing and gloss polishing of side bottom workpieces are impossible, and the chemical polishing agent is expensive, making it difficult to put it into practical use.

The present inventors investigated combinations of various inorganic acids, organic acids, and peroxides, and found that a mixed system of monocarboxylic acid and hydrogen peroxide is particularly effective in improving polishing speed and surface precision. We have arrived at the present invention.

There is a range of monocarboxylic acid to hydrogen peroxide concentrations suitable for barrel polishing, with a molar ratio of acetic acid to hydrogen peroxide of 0.
2~/, 6, for formic acid to hydrogen peroxide, the molar ratio is O0/~0
．． This range is valid. That is, for acetic acid-hydrogen peroxide based polishing agent, the acetic acid content is 20017 or less and hydrogen peroxide is /301/L or less, and for formic acid-hydrogen peroxide, formic acid is 2 o t/L or less and peroxide is It is appropriate that hydrogen is 2 soVt or less. If the molar ratio is less than the above range, the polishing rate (polishing efficiency) will decrease, and if it exceeds this range, the copper-zinc alloy will exhibit a so-called dezincing phenomenon, and the surface of the copper-processed copper alloy will become rough, resulting in poor smoothness and Glossiness was inhibited.

Furthermore, adding a small amount of nitric acid to the monocarboxylic acid-hydrogen peroxide mixture system will have the effect of increasing the polishing rate without impairing the smoothness and gloss of the workpiece. The molar ratio of acetic acid to hydrogen peroxide is o, 7 is 1. - Below is also the molar ratio of formic acid to hydrogen peroxide. . An abrasive with a molar ratio of nitric acid and formic acid to hydrogen peroxide of 0.7 or less in the range of 3 to O,S is effective, and outside this range the surface of the workpiece is roughened.

In addition, although acetic acid and formic acid were mentioned as examples of monocarboxylic acids above, easily water-soluble monocarboxylic acids such as propionic acid, acrylic acid, butyric acid, etc. can also be used in the barrel polishing method of the present invention. Furthermore, the surface of the workpiece after barrel polishing has a yellowish brown color, but 0. If it is washed with a diluted nitric acid solution of l-flat, a metallic luster will appear, and if the gloss finish is achieved in a short time by ordinary barrel polishing, better gloss and smoothness can be obtained.

Hereinafter, the present invention will be further explained with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Brass test Je (BIB) and polishing stone 3P-za manufactured by Shikishima Tipton Co., Ltd. and various barrel polishing machines manufactured by Shikishima Tipton Co., Ltd. were loaded and the polishing conditions with chemical abrasives were observed.

The chemical polishing agent was prepared by blending the following ingredients, diluting and dissolving it in water, and charging the chemical polishing agent in the above amount into each barrel polishing machine. For the control example, a compound QCPy manufactured by Shikishima Chipton Co., Ltd. was charged at a ratio of Comparing only barrel polishing in Example 1, a significantly larger amount of polishing was obtained with the rotating barrel, approximately 90 times with the vibrating barrel, and approximately 5 times with the centrifugal rotating barrel.

Also, compared to immersion in chemical abrasives, the amount of polishing is approximately 1.3 times with the same composition of rotating barrel, and the surface roughness is /
,? O was significantly improved from IE& to OoSIlm. Also, when the chemical polishing agent mixture composition exceeds the range, the surface roughness deteriorates, and when it falls below the range, the amount of polishing is small (it has not been put to practical use).

Example 2 Brass faucet bag nut (dimensions 29yIX/-1, weight x
The vibrating barrel CL-t manufactured by Shikishima Tipton Co., Ltd. was used to remove deburrs after cutting and form t) and to give a glossy finish as a pre-plating treatment.
oo and the following polishing stone.

(1) Rough finishing (barrel polishing only) (2) Semi-finishing (barrel polishing with chemical polishing agent) - Min.↓ + / IqN After performing rough finishing and semi-finishing under the above polishing conditions, wash the mass with water, After washing with 0.3% nitric acid solution and water again, the resulting workpiece was given a glossy finish.The resulting workpiece was rich in metallic luster and had no dents measuring 0.3 μm in diameter on each surface (1 surface was coated with nickel chrome plating). The product had excellent smoothness and gloss, and good plating adhesion, but it required 3 hours of polishing time due to the threads (P8-j), which caused problems with deformation of the threads and plating adhesion. .

As stated above, according to the present invention, by using a monocarboxylic acid-hydrogen peroxide based chemical polishing agent for copper and copper alloys as a compound for barrel polishing, polishing efficiency can be significantly improved. We were able to solve all the problems with conventional barrel polishing and chemical polishing.

In addition, inexpensive nitric acid #1 is used for monocarboxylic acid-hydrogen peroxide systems. Not only can the polishing efficiency be further improved by adding
This allows for cost reduction.

Kazuo Wakasugi, Commissioner of the Patent Office1. Indication of the incident Relationship to the 1980 Patent Application No. 14176/case
Patent applicant 4, agent (zip code 160) Address Chitokumei Building, 29 Shinanomachi, Shinjuku-ku, Tokyo Telephone: Tokyo (353) 3407 (actor) Z Contents of the amendment (1) Specification page G, line g ``Nitric acid-hydrogen peroxide'' is corrected to ``nitric acid-hydrogen peroxide.''

(, 2) In the iqth line of page g of the specification, the phrase "(BSB)" is corrected to "(BsB)".

(3) On page 13, line 5 of the specification, there is a statement that says ``the following polishing stone''.
The following has been corrected to read "Abrasive stones and compounds made by Shikishima Chip Co., Ltd."

(Hiroshi) Specification/Page 1/Line 2-13: “Monocal?
The text that says "rim - hydrogen peroxide" has been corrected to "monocal rice - hydrogen peroxide."

Claims (1)

[Claims]! Barrel polishing method combined with chemical polishing characterized by charging a polishing material, a monocarboxylic acid/hydrogen peroxide type chemical polishing agent, and a copper or copper alloy workpiece into a polishing tank and performing barrel polishing. The carboxylic acid is acetic acid, and the content of acetic acid in the acetic acid-hydrogen peroxide chemical polishing agent is 2ooVL ~ 29-/l.
, the content of hydrogen peroxide is /30f//L-/t/L
Barrel polishing method combined with chemical polishing according to claim 1, characterized in that the monocarboxylic acid is formic acid, and the content of formic acid in the formic acid-hydrogen peroxide chemical polishing agent is 100 f. /l~714, hydrogen peroxide content is 2! Barrel polishing method combined with chemical polishing according to claim 1, characterized in that the abrasive material, monocarboxylic acid-hydrogen peroxide based chemical polishing agent, and nitric acid are introduced into the polishing tank. Barrel polishing method combined with chemical polishing characterized by barrel polishing by charging copper or copper alloy workpiece.The nitric acid added has a molar ratio of acetic acid to hydrogen peroxide of 0.7.
~i, o, and the molar ratio of nitric acid and acetic acid to hydrogen peroxide is 1. Barrel polishing method combined with chemical polishing according to the item No. 2 of the claims, characterized in that the molar ratio of nitric acid to hydrogen peroxide to formic acid is O, S
~OOS, and the molar ratio of nitric acid and formic acid to hydrogen peroxide is 0.7 or less, Barrel polishing method 7 combined with chemical polishing according to claim d, in a polishing tank After barrel polishing is performed by charging an abrasive material, a monocarboxylic acid-hydrogen peroxide based chemical polishing agent, and a copper or copper alloy workpiece, the workpiece is cleaned with a dilute acid solution, and then a regular barrel polishing is performed. To achieve a glossy finish by polishing:
Featured barrel polishing method with chemical polishing A barrel polishing method combined with chemical polishing, characterized in that the workpiece is cleaned with a dilute acid solution and then polished to a glossy finish by ordinary barrel polishing.