After bright pickling, copper parts in textile industry will be oxidized and discolored quickly if they are not treated with anti discoloration passivation. In the past, chromate is usually used for anti discoloration passivation, but hexavalent chromium wastewater will be produced in chromate treatment. The RT anti copper discoloration agent developed by our company does not produce harmful waste water. The salt spray and atmospheric exposure tests show that the discoloration resistance is better than chromate passivation, and the solderability is not affected.

1、 Preparation

RT anti copper discoloration agent 1 part (100 ml / L)

Water (distilled water or deionized water if possible) 9 parts (900 ml / L)

PH 8.0-8.5 (adjusted with ammonia)

The temperature is 10 ～ 60 ℃

The time was 0.5-1 min

2、 Process flow

Oil and film removal (generally this process can be omitted) → chemical polishing of copper parts → water washing → immersion of RT anti copper discoloration agent → water washing → centrifugal drying or compressed air drying or drying (temperature 90 ~ 110 ℃). Time: 3-5 minutes).

3、 Maintenance methods

1. The pH value of passivation solution must be kept in the range of 8.0 ~ 8.5 and adjusted with ammonia water;

2. At ordinary times, the consumed solution is added according to the proportion of preparation.