35 Ill. Adm. Code 211.2040
Etching Filler
Section 211.2040 Etching Filler
"Etching filler" means,
for purposes of 35 Ill. Adm. Code 218 and 219, a coating that contains less
than 23 percent solids by weight and at least 0.50 percent acid by weight, and
is used instead of applying a pretreatment coating followed by a primer.