Design Development and Performance Research of Eco-Friendly Film Stripping Solutions for Printed Circuit Boards

Abstract

In order to improve the environmental friendliness of the film stripping solution for printed circuit boards, through experimental research, the formula of the eco-friendly film stripping solution with inorganic alkali as the main component was determined to contain: inorganic base NaOH at 0.5 mol/L, film breaker diethylene glycolmonobutyl ether at 10 mL/L, surfactant alcohols R at 5 mL/L, tin protectant potassium citrate at 1 g/L, with the remainder pure water. The film stripping solution was found to be colorless and transparent, maintaining a stable state. Under the condition of a temperature of 50 ℃, the film was removed within 50～70 s, the size of the film ranged from 5 to 10 mm, the average tin thickness variable was less than 0.5 μm, and the ammonia nitrogen value was measured at 4.632 mg/L. Comparing the film stripping solution with products from the same production line, it was found that the film stripping performance of the two was extremely close. The eco-friendly film stripping solution exhibited lower ammonia nitrogen value and chemical oxygen demand(COD) values, which not only met production needs but also offered good environmental friendliness, thereby reducing the treatment cost of the film stripping waste liquid.

Keywords

• printed circuit board; film stripping solution; eco-friendly