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Etching Glass using HF or other product.

We do Acid Etching of Glass bottles for the cosmetic industry in South Africa. The company who supplies us with Ammonium Bifluoride has no stock. They giving us some story that its used for the manufacturing of narcotics and their suppliers can get a export permit. So they say I should use HF we have had the chemical company here to give the training regarding HF. I am not happy going this route but we need to service our customers. We did some trials with 40% HF and a 60% HF but no luck the chemical company here is not very help full. I am not to sure if we need to add something else or not. It just eats the glass and doesn't do any etching. Our Ratio with ABF was 40 kg and 20 Liters HCl this worked perfect we submerged the glass in this solution for about 90sec.Or if there as another product we could use instead of HF.

Sean Schlebusch
Manufacturing - JHB, So. Africa
May 19, 2011

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If you do not have a chemist on staff, go to a college and find an instructor or student that can convert the values of your old solution to a new solution. Try that in a small container and tweak it as required.
Your new solution will be considerably more acidic because it has two sources of hydrogen ions, but the fluoride ion is the operative attack. HF is a weakly ionized acid, so it is not going to be vastly different than the ammonium bi fluoride. It will require some trial and error testing, but that is not impossible if you approach it in an organized manner.

James Watts
- Navarre, Florida
May 19, 2011

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Though it may sound obvious please remember not to store or test the hydrofluoric acid or its mixtures in glass containers. Use polyethylene or other resistant plastic vessels instead.
G. Marrufo

Guillermo Marrufo
Monterrey, NL, Mexico
May 22, 2011

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May 24, 2011

If you do not have a chemist on site, you may wish to avoid really nasty materials like HF

If the image you are producing is reasonably simple, it may be worth investigating sand-blasting through a suitable mask (rubber or polyurethane). Much safer, controllable and no residues to dispose of.

Geoff Smith
Hampshire, England

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Hi

Thanks for the feed back. Our biggest thing is to get some form of mixing Ratio. We are total stuck we don't have any Ammonium Bifluoride will only receive stock in 8 weeks time. So for the meantime we need to etch bottles. Please I need help.

Sean Schlebusch
- Manufacturing - JHB, So. Africa
May 30, 2011