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Pre-paint chemical treatment for better salt spray results

The steel parts we are painting after phosphating and treatment with deoxylyte is giving 96 hrs salt spray. But due to environment concern we plan to use amine based chemical treatment after phosphating. This gave 24 hrs salt spray. Paint adhesion is also good for amine based chemical treatment parts. How to increase salt spray result? I understand some other chemical treatment can solve the problem. Any guidance?

M. DAVIDSON
- Mumbai, Maharashtra, India
2006

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Dear Davidson,

For giving better adhesion with paint always require little acidic balance on surface. if you are leaving alkaline effect over the treated surface it will reduce the adhesion properties. Secondly Do not use caustic base cleaner and acid pickling in the treatment line to improve salt spray life of the subtract.

Navin Maheshwari
- New Delhi, India
2006

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Hello Sir,

You said the presence of alkali will alter the adhesion of the paint. But we are using alkaline dip primer for our pallets. I don't think that the alkaline paint will affect the adhesion of the paint. Kindly confirm.

S.V. Aurobind
plating process supplier - Bangalore, India
2006