Coating processes – Direct application of electrical – magnetic – wave – or... – Sonic or ultrasonic
Patent
1997-01-29
2000-03-14
Talbot, Brian K.
Coating processes
Direct application of electrical, magnetic, wave, or...
Sonic or ultrasonic
427601, 427 97, 427122, 205125, 205 91, 205148, B05D 512, B05B 100
Patent
active
060370203
ABSTRACT:
A method for treating a non-conductive through hole surface of a printed wiring board is disclosed. A printed wiring board including through holes is cleaned, conditioned, and a conductive coating is applied to the initially-nonconductive through hole by contacting it with a series of baths. The conductive coating, for example a graphite dispersion coating, facilitates later electroplating of the conductive surface. While at least partially immersing the through hole in one or more of these baths, ultrasonic energy is introduced in the bath in the vicinity of the through hole. The ultrasonic energy can be introduced during the entire immersing step, before the immersing step, or both. The ultrasonic energy reduces the formation of blowholes during later processing (and especially soldering) of the printed wiring board. The ultrasonic treatment can also improve the dispersion of the conductive particles in a conductive carbon dispersion, reduce or eliminate the formation of pinhole defects, and provide other advantages.
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Presenting Our New In-Line Mixer-Disperser Type HED.
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Carano Michael Val
Carroll Benjamin Todd
Garlough Gregory Dean
Polakovic Frank
Electrochemicals Inc.
Talbot Brian K.
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