Water quality requirements for PCB cleaning
Importance of DI water quality
Deionized (DI) water prevents mineral deposition and ionic contamination after rinse. Key parameters: resistivity (>10 megaohm-cm preferred), low TOC, and absence of particulate.
Poor water quality causes white residues, elevated ionic conductivity, and corrosion.
Testing water quality
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measure resistivity and conductivity continuously for final rinse loops;
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periodically test TOC and microbial levels;
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use inline particle filters and monitor pressure differentials.
ZESTRON integrates water quality specifications into process audits and recommends DI recirculation and polishing systems for critical lines.