PPG Sigma Etch Amercoat 59TW, T Wash or also known as Mordant Solution, is a phosphoric acid based etch solution for treating new un-weathered galvanised surfaces prior to painting.
Suitable for use for pre-treatment of new galvanised steel where blasting or abrasion is not possible. Highways Item No. 155.
PPG Sigma Etch is a high quality etching solution that can be used to give adhesion of high temperature coatings to new galvanised steel that lacks abrasion. As well as this, Sigma Etch can be used as part of a wide range of protective coating systems that can be over coated with many different primers and topcoats.
PPG Sigma Etch is a pale blue solutions which blackens after application to indicate the effectiveness of the primary treatment and can be applied easily using a paint brush. Sigma Etch (T Wash) has a theoretical coverage rate of 15m2 per litre.
Surface and Environment
Sigma Etch mordant solution can be used on all clean, galvanised substrates to etch the surface and provide adhesion, ideal for preparing the substrates ready for a protective and decorative coating.
- Highways Agency Item No.155
- PPG Sigma Etch Amercoat 59TW, T Wash or also known as Mordant Solution
- May be over-coated with a wide range of protective coating systems.
- May be used to give adhesion of high temperature coatings to new galvanised steel.
- Changes colour on application from blue to black to indicate the effectiveness of primary pre-treatment.
- Meets the requirements of Network Rail's Mordant Solution 't-wash' solution.
- Not recommended for immersed conditions.
- Theoretical spreading rate 15 m2 per litre
- Available in 5 Litres