Device for sequential spray application of chemical solutions used in the preparation of circuit board inner layers

摘要

Disclosed is a device for continuously and sequentially applying Durabond TM treatment chemicals or any similar chemical system used in the manufacture of multilayer printed circuit boards. The device of the invention generally comprises a mechanized conveyor line having spray manifolds positioned above and below the line at various points so as to effect the desired sequential spraying of the treatment chemicals and rinse solution. Chemical containment sumps or tanks are specifically sized so as to provide coordinate solution volumes, thereby minimizing the need for intermittent shut down of the line to replenish individual solutions. The provision of such coordinated solution volumes also prevents chemical waste. A multistage water rinse is employed at one point in the inventive process to insure that all excess immersion tin solution is thoroughly rinsed from the surfaces of the circuit board layers. Such multistage rinse includes at least one high pressure water rinse in excess of 100 psi. A plurality of specialized rollers are employed to level and/or evenly disperse post treatment solution over the surfaces of the circuit board inner layers. Such specialized rollers preferably comprise a metal core having a chamois-like silicon free natural fiber covering disposed thereupon.