Homebrew PCBs

Silver is currently $29 per ounce on the spot market, but you can't buy it for that.  $2.00 per gram for silver acetate sounds like  bargain.

John

  ----- Original Message ----- 
  From: Dave 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Thursday, January 19, 2012 11:08 AM
  Subject: [Homebrew_PCBs] Re: Silver Ink


    
  --- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@...> wrote:
  >
  > The silver acetate seems to go for about $2 USD per gram from 
  > "legitimate" sources, less from ebay. 

  Is that lab grade or technical grade? There's a HUGE price 
  difference between the 99% purity stuff, and the 99.9% purity 
  stuff. :-)

  For that matter, has anyone researched how to produce Silver 
  Acetate themselves? It's probably a lot more complex than 
  simply dropping some Silver coins into a bottle of vinegar.

  Ok, having looked it up on wikipedia, it looks like there's a
  three step process (Silver + Nitric Acid->Silver Nitrate + 
  Sodium Carbonate -> Silver Carbonate + Acetic Acid -> 
  Silver Acetate.). That's not too complex. I think the real
  problem with the cost is that the price of Silver is rather 
  incredible at the moment.

  > They mix 1 g with 2.5ml of ammonium hydroxide plus .2ml formic 
  > acid. Assuming you can get 2 ml of ink from the mixture and that 
  > the cost of the ammonium hydroxide and formic acid are negligible 
  > (???), the cost would be about $1 USD/ml. 

  Ammonium Hydroxide is simply ammonia in water.

  Formic Acid isn't too hard to synthesize (via a couple of routes),
  so it should be reasonably cheap. Don't get it on you. It's
  the active ingredient in bee and ant stings.

  > Since you are only drawing traces, it shouldn't be too 
  > expensive, especially if you can reuse any ink wasted in head 
  > cleaning. Anyone interested in a group buy of the chemicals?

  I doubt that the cleaned ink from the head could be reused. But,
  a little care in batching up the plots could minimize waste.

  > Mark

  Dave <- Not a chemist, but I occasionally bathe in H2O!



  

[Non-text portions of this message have been removed]