Acid-Resistant Protective Coating for PCBs

In 2003, Japan's Fluorotechnology launched the Fluoro Surf® FG-3000 series, a fluorine-based moisture protection coating specially designed for printed circuit boards (PCBs) and electronic components. It quickly achieved impressive market performance. Let’s take a closer look at this advanced fluorinated moisture-proof coating.

Specifically developed for moisture-proof, waterproof, and acid-resistant applications in PCBs, the Fluoro Surf® FG-3000 series demonstrates excellent moisture resistance and insulation properties. It serves as a high-performance insulating and protective coating for circuit boards and components, offering superior acid and corrosion resistance.

Traditional water- and oil-repellent treatments often result in films with poor mechanical strength that are prone to cracking under thermal shock. As a result, the film thickness of conventional products is limited to a maximum of 1μm (with 2% resin concentration).

Figure 1 shows copper foil (0.1 mm thick) immersed in 10 wt% nitric acid solution. While the uncoated sample dissolved completely within 24 hours, the fluorine-based coating (about 5 µm thick) preserved the copper foil even after immersion.

Figure 1: Copper foil immersed in 10% nitric acid solution at room temperature (25°C)