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Corrosion of Zn plated steel in antistat bags

2004

We found that our products with zinc plated steel were getting corroded within days. These were packed in pink anti-static bags. The problem was more in high humidity regions of the world. There were no hand prints as assembly was done with cotton gloves.

I heard that anti-static can act as a catalyst in corrosion process. We sprayed two sheet metal pieces with water, covered one with anti-static bag and put them in thermal chamber at 50C. The one in the bag corroded in two hours. I would like to hear from anyone about this problem.

Thanks,

Rajesh Nair
Electronics products - Nashua, NH, USA

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Yes, Airtight PVC packing will cause sweating and premature corrosion. Try using cotton cloth bags or anticorrosive paper for more corrosive high humidity areas.

Khozem Vahaanwala
Saify Ind

Bengaluru, Karnataka, India

2004

One problem can be moisture trapped on the zinc plated surface not dried up enough, and bagging before drying properly. A low temp bake cycle or vacuuming parts before bagging could help.

Mandar Sunthankar
- Fort Collins, Colorado
2004

We seemed to have similar problems with pink bags at my company. Copper surfaces became non-conductive after being stored in pink bags. A co-worker of mine had experienced a similar problem at a prior company.

Michelle Wright
- Carlsbad, California, USA
2005

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2005

Amines in pink bags cause corrosion. Therefore manufacturers have moved away from allowing amines in their pink bags. Make sure that your pink poly bags are amine-free.

See esdproducts.biz/Packaging/1206p/1206p.htm:
"Elimination of amines from the resin has eliminated the greasy feeling of the surface typical in antistatic bags. This allows the bag to be written on and opened more easily. It eliminates corrosion caused by outgassing."

Michelle Wright
- Carlsbad, California, USA

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2007

Users can eliminate damage of electronic parts caused by corrosive environmental gases, ESD and bacteria using Static Intercept bags which have been extensively tested
and found to be able to protect articles:
1. for long periods against corrosive gases and VOC
2. permanently against ESD
3. growth of micro-organisms.
The bags are re-usable and re-cyclable which not only cut costs considerably but also contributes to environmental sustainability. No chemicals are involved and packaging process is simplified.

C H Tng
- Singapore