Homebrew PCBs

Hi All,
Can anyone tell me what this etchant is? I have not seen such before.

 http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053

Thanks,

On 23/09/2012 16:23, David wrote:
> Hi All,
> Can anyone tell me what this etchant is? I have not seen such before.
>
> http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053

Ammonium persulphate?

Leon
-- 
Leon Heller
G1HSM

I buy a lot of stuff in china, but bags of white powder, I'm not so sure ;-)

ST

On Sun, Sep 23, 2012 at 5:23 PM, David <dgh2259@...> wrote:
> Hi All,
> Can anyone tell me what this etchant is? I have not seen such before.
>
>  http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053
>
> Thanks,
>
>
>

I used some of that etchant and its storage life was not good. Mix just what you need by figureing out board size, per
specs that come with that bag only and it will work, and work ok but storage life was not all right there for a lot of money wasted I think. I later on bought a 1 lb. container of  Ferric chloride, anhydrous 99.8% and its storage life is better and I beleive a better deal. I also found it on E-Bay.

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

This is just a guess, but that is what others seem to be doing too.

From the description (solid powder, clear solution becoming colored but still clear) it is probably a "per"xxx something.  Persulfates are common, like ammonium persulfate and sodium persulfate.

The ringer is the white solid precipitate at the end of the etch.  Now, that can be done with a second step to precipitate either the sulfate (e.g., add calcium or barium hydroxide), or one can precipitate the copper and get a slightly green (usually) powder.  But, the description implies a second step is not necessary.

I was thinking it might be one of the so-called "solid hydrogen peroxides."  The percarbonates or perborates would fit into that category.  The percarbonate would be interesting as that would leave copper carbonate as an insoluble powder.  Problem is, I am not sure it will etch under alkaline conditions.  Under acidic conditions, the copper (II) would most likely be soluble.  Borate is a different story.  I couldn't find after a brief search the actual solubility of copper(II) borate, but it precipitates from water solutions readily.  (Copper(I) borate is reportedly soluble in water.)

So, taking everything that was stated as true, including the statement that the solution it is mildly acidic, I would guess it maybe a soluble perborate salt and may have a little free boric acid present.  A percarbonate salt is another option, but doesn't account for the acidity.  If sodium phosphate were present, the precipitate might be copper phosphate.  That might solve the solubility problem with any of the "perxxx" type of compounds.  The white granules being sold many be a mixture to account for all of the described properties.

John

  ----- Original Message ----- 
  From: David 
  To: Homebrew_PCBs@yahoogroups.com 
  Sent: Sunday, September 23, 2012 11:23 AM
  Subject: [Homebrew_PCBs] Etchant Identification


    
  Hi All,
  Can anyone tell me what this etchant is? I have not seen such before.

  http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053

  Thanks,



  

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

Have you asked the seller? As far as I can tell, it is a white crystalline product. Absolutely nothing more than that.

Donald.
--
*Plain Text* email -- it's an accessibility issue
()  no proprietary attachments; no html mail
/\  ascii ribbon campaign - <www.asciiribbon.org>

----- Original Message -----

> From: "David" <dgh2259@...>
> To: "Homebrew PCBs" <Homebrew_PCBs@yahoogroups.com>
> Sent: Sunday, September 23, 2012 11:23:30 AM
> Subject: [Homebrew_PCBs] Etchant Identification
> Hi All,
> Can anyone tell me what this etchant is? I have not seen such before.
> 
> http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053
> 
> Thanks,
> 
> 
> 
> 
> ------------------------------------
> 
> Be sure to visit the group home and check for new Links, Files, and
> Photos:
> http://groups.yahoo.com/group/Homebrew_PCBsYahoo! Groups Links
> 
> 
>

Looks like ammonia per-sulphate,that turns light blue when mixed with water,and its more environmentally safe.
Don,t mix it all if you buy it only mix enough for the job

Sent from my iPad

I agree with Leon: Ammonium persulphate. One of my favorites. Easy to see the etching process. Nice clear Blue and no real nasty smell etc. Turns darker and more green when full of copper. In dry form last a long time.

I've been low key lately. I want to try out the hydrochloric acid and peroxide enchant soon.

-Lee

--- In Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@...> wrote:

>
> On 23/09/2012 16:23, David wrote:
> > Hi All,
> > Can anyone tell me what this etchant is? I have not seen such before.
> >
> > http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053
> 
> Ammonium persulphate?
> 
> Leon
> -- 
> Leon Heller
> G1HSM
>

Gent's,
Thank you all for your input on this matter!
I think we can comfortably say its Ammonium Persulphate, going to give it a try, Ferric Chloride is a real messy affair!!
Will provide some feedback once I have tried it.
-David

--- In Homebrew_PCBs@yahoogroups.com, "studleylee" <indigo_red@...> wrote:

>
> I agree with Leon: Ammonium persulphate. One of my favorites. Easy to see the etching process. Nice clear Blue and no real nasty smell etc. Turns darker and more green when full of copper. In dry form last a long time.
> 
> I've been low key lately. I want to try out the hydrochloric acid and peroxide enchant soon.
> 
> -Lee
> 
> --- In Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@> wrote:
> >
> > On 23/09/2012 16:23, David wrote:
> > > Hi All,
> > > Can anyone tell me what this etchant is? I have not seen such before.
> > >
> > > http://www.ebay.co.uk/itm/1pc-Copper-clad-palte-CCL-PCB-blue-environmental-protection-etchant-200g-/251130218053
> > 
> > Ammonium persulphate?
> > 
> > Leon
> > -- 
> > Leon Heller
> > G1HSM
> >
>

On Wed, Sep 26, 2012 at 3:36 AM, dgh2259 <dgh2259@...> wrote:
>
> I think we can comfortably say its Ammonium Persulphate

Ammonium Persulphate is good (I like the colour), but won't etch
unless the temp is >70C (>160F).

> Ferric Chloride is a real messy affair!!

Yeah.  But it doesn't have to be, with the technique here:

  http://www.instructables.com/id/Sponge-Ferric-Chloride-Method-Etch-Circuit-Bo/

Uses a tablespoon of liquid, and etching is done in under a minute.
Nothing short of amazing.  For this reason, I went back to Ferric
Chloride.

My blog article about home-made PCBs:

  http://capnstech.blogspot.com.au/2011/05/playpause-making-pcbs-at-home.html

Mitch.