Nickel-removing solution for adverse chemical nickel plating layer of printed circuit board and preparation method thereof and method for removing adverse chemical nickel plating layer

Abstract

The invention discloses nickel-removing solution for an adverse chemical nickel plating layer of a printed circuit board (PCB) and a preparation method thereof and a method for removing the adverse chemical nickel plating layer, and solves the technical problems of reducing the extra cost of the PCB and keeping the physical property of the PCB after reworking treatment. Each liter of nickel-removing solution contains 10 to 300 grams of sodium persulfate, 10 to 200 grams of sulfuric acid solution, 0.1 to 100 grams of alkyl ketone corrosion inhibitor and 0.1 to 50 grams of thiazole corrosion inhibitor. The method for removing the adverse chemical nickel plating layer comprises the following steps of: removing oil from an adverse nickel plating PCB, soaking the adverse nickel plating PCB into the nickel-removing solution, and taking the PCB out at a proper time calculated by removing 4 microns of a nickel layer every 15 minutes. Compared with the prior art, the method has the advantages of low cost, environmental protection, short nickel-removing time and constant nickel-removing speed; and the solution nearly does not damage a copper base material, and the copper loss of the naked copper base material in the nickel-removing solution is less than 0.5 micron per hour, so the integrity of a thin circuit can be well ensured.

Description

technical field [0001] The invention relates to a nickel stripping liquid for printed circuit boards and a preparation method thereof, and a method for removing bad coatings by using the nickel stripping liquid, in particular to a nickel stripping liquid for copper substrate printed circuit boards and a preparation method thereof , and a method for removing a bad coating by using the nickel stripping solution. technical background [0002] With the rapid development of the electronic information industry, 3C products are also popularized and deepened, and at the same time, it drives the rapid development of the printed circuit board PCB (Printed Circuit Board) manufacturing industry. As a key component of electronic products, PCB is a very complicated process from design to production, and then to the integration of electronic components. Any error in any link will lead to a sudden change in the nature of the final product, and the chemical nickel-gold process is PCB product...

AI Technical Summary

Problems solved by technology

Nitric acid has a large fume and is harmful to the human body. It has a strong solubility for nickel and copper and is difficult to control.

Hydrogen peroxide is not stable, easy to volatilize, deplating is unstable, and the surface damage to the base copper is also great, especially for circuit boards with very thin lines and thin base copper, it is not suitable at all, often nickel The thin copper wire on the line is also broken

For the alkaline deplating solution, the alkali concentration is often high, and the use temperature is high, and the ink and solder mask of the circuit board cannot withstand its erosion.

The method of stripping nickel with high concentration of strong acid and strong alkali will also bring about the problem of environmental pollution