AEROSIL® Fumed Silica in etch resist inks for printed circuit boards

Printed circuit boards undergo a number of production steps, before being finally put to use in today’s electrical goods. One important step is to ensure that the conductive wires are clear from imperfections.

Typically AEROSIL^® products are used as additives to control the rheology of special etch resistant inks. Therefore ensuring conductive wire is fully protected during the etching process. At the same time, etch resist inks protect the circuit from every day conditions such as heat, moisture and dust.

The AEROSIL^®portfolio includes a number of products ideal for different formulations the main ones being:

Properties of main products
Product	Specific surface area (BET)	pH (in 4% dispersion)	Surface treatment
AEROSIL^® 200	200 ± 25 m²/g	3.7-4.7	Hydrophilic
AEROSIL^® 300	300 ± 30 m²/g	3.7-4.7	Hydrophilic
AEROSIL^® 380	380 ± 30 m²/g	3.7-4.7	Hydrophilic
AEROSIL^® R 972	110 ± 20 m²/g	3.6-5.5	Hydrophobic
AEROSIL^®R 974	170 ± 20 m²/g	3.7-4.7	Hydrophobic