Etching is the method used to produce printed circuit boards. A temporary mask protects the laminate from acid and leaves the etched copper layer. Acid removes the unwanted copper from the laminate. One factor to consider when you do PCB etching yourself is the waste disposal. Etching requires the use of toxic chemicals that cannot be flushed down the toilet or poured down the sink.
Instructions
1 Check the label for disposal instructions. Two acids used in etching are ferric chloride and sodium persulfate. Some manufacturers provide information on how to dispose of toxic chemicals.
2 Reuse and recycle the chemicals if possible. Use the same chemicals for other PCB etching projects. Contact an etching facility to determine if they have a need for the chemicals that you've used.
3 Call the waste disposal department for your city to obtain recommendations for waste disposal. Drop off hazardous materials with the city for disposal, if allowed. Pay a fee; some cities charge for this service.