CCL Blue vs Ferric Chloride Etchant

[Ian.M]

Part of the storage problems may be the purity or lack there of of the mysterious chemicals sold on EBAY.   Ferric Chloride is cheap, and not too sensitive to purity, so in that case you are likely to get what you pay for, but %DEITY% knows what's in 'CCL Blue Etchant' powder.  We only know it contains a high proportion of Ammonium Persulfate, from its decomposition products.  The other part of the storage problem is probably Malaysia's climate. (Assuming O.P's location flag is correct) Its neither arid nor cool, both of which are requirements for long-term storage of solid Ammonium Persulfate.  Its recommended to store it below 25 deg C, and in bulk industrial quantities, properly stored, it has a shelf life of only three years with noticeable caking in as little as a year.  Its storage container needs to keep water vapour out but vent over-pressure without popping its lid off or bursting.  Solutions are not stable, especially when contaminated, to the point that all the major laboratory chemical suppliers advocate preparing them fresh.

I have edited my previous post to clarify that I am talking about hydrated ferric chloride, NOT ANYTHING ELSE. 

Although you cant store mixed Hydrochloric Acid + Hydrogen Peroxide etchant, its the starter for the air regenerated acid Copper(II) Chloride etchant system, so just tip in an excess of finely divided copper (e.g. scrap un-tinned stranded wire, stripped of its insulation and untwisted and crumpled) into your used etchant, to convert it to stable, storable Copper chlorides (however don't do this before disposal - you don't want to increase the copper concentration).

[Mechatrommer]

Ferric chloride can be made from iron, hydrochloric acid and hydrogen peroxide (however, I know you can't make it by simply adding iron to hydrochloric acid), but since that requires one more ingredient than my formula, and makes a worse etchant to boot, I don't see the point.

yup i've provided links to what you said. i'm not going to diy FeCl3 since i already ordered small quantity (560g FeCl3 dilute to 2L liquid) from our local online seller (i just found out we now have this locally, and it also affordable cheaper). we also have 3% hydrogen peroxide sold, but hydrochloric acid is still nowhere to be found unless from usa, german or romania at premium price + shipping. i'm not going to buy that corrosive and risk a leakage in an airplane.

I'm still no closer to knowing what your mystery white powder called "CCL Blue" is after looking at that hilarious ebay link, but most likely it is a persulphate salt of either ammonia or sodium or potassium.

well now it is revealed it some sort of ammonia and persulphate... since you havent used it, my advice is, dont buy it. its useless for making a board in a blue moon, only in mass production as people have mentioned here.

And if the OP is concerned about ecology/storage, hydrochloric acid + peroxide combo likely isn't a very good suggestion.

hell no. i dont care i just want to etch some pcb. i dont even know and care what components of that "CCL blue" white salt comprises until now. people adviced using glove i'm not going to, i just wash my hand afterward. i've experiment with many corrosive liquid with my hand nothing will peel off my skin at an instant, the worst chemical i've work with is car paint remover, but that i only experience a nasty itch in small quantity. so i know its a big no no if touching skin in big quantity. this ammonia sulphate is nothing near that hazard. i'll throw it anywhere at worst some giant lizard will die, well good for us giant lizard is a big harassment to the neighboorhood.

(Assuming O.P's location flag is correct) Its neither arid nor cool, both of which are requirements for long-term storage of solid Ammonium Persulfate.

we are known for 90% RH, the good part is we dont experience much semiconductor damage due to electrostatics here.

anyway, i've ordered my 1st pack of FeCl3, cant wait for it to arrive for me to learn some chemistry lesson.

[Monkeh]

That first pack of FeCl₃ will last you a long time.

Wear gloves. Really. It stains everything.

[Mechatrommer]

we'll see about that

[MagicSmoker]

...hydrochloric acid is still nowhere to be found unless from usa, german or romania at premium price + shipping. i'm not going to buy that corrosive and risk a leakage in an airplane.

Check the pool section of a hardware store, or, of course, a pool supply store. Hydrochloric acid is used to lower swimming pool pH here, and I have to think the same market forces would prevail in Malaysia (ie - HCl is cheap and gets the job done).

[CatalinaWOW]

Be sure to look for alternate names for hydrochloric acid.  Here in the US you can't find hydrochloric acid anywhere except chemical supply houses at a premium price.  But it is widely and cheaply available at swimming pool maintenance places and hardware stores under the name muriatic acid.  Other names I am aware of include "spirits of salt" and "acidum salis".  I am sure there are others.

[BrianHG]

Ferric chloride at 70-80 deg C will etch more copper, faster (like a few minutes), with more consistent speed.  However, at this temp, there are fumes and they will damage/corrode exposed metals in you work-shop if you don't have good ventilation.

Oh my. I've never used ferric chloride hot like that. Always at room temperature, or slightly warmed to 30 C or so. I fear to think how it would behave if you make it as hot as that.

45 seconds to etch a PCB!
Instead of a circulation pump, I would just wiggle the PCB for the 45 seconds & voila, perfect PCB.
I'd do 1 at a time, though, this would slow down to 1.5minutes after ten double sided 12inx12in pcbs before I started using GND pours everywhere.  Then, it took around 50 PCBs before it even began to slow down to 1.5 minutes per PCB.
(You can tell I'm impatient...)

[BrianHG]

Another thing I noticed about ammonium persulphate crystals etching.  The slightest scratch on your protective coating would etch.  Seriously, I'm talking about having a trace clearance on the scale of 1 mil, the crystals would slightly over etch making the opening an extra 1/2 mil on each side resulting in a PCB with a 2mil gap, no shorts.  Ferric chloride didn't have this fine guaranteed clearance.  I believe it has to do with the viscosity difference of the 2 fluids.  Maybe lower viscosity ferric chloride mixtures exist.  Raising it's temp did make it flow much easier...

Once again, remember to copper fill all unused areas of your PCB, extend the life of your etchant chemicals.
Help minimize the impact on the environment with this simple trick and save yourself some money as well.

[KL27x]

is it wise to buy 1Kg dry FeCl3?

"Dry FeCl3" is an oxymoron. It's extremely hygroscopic. As soon as you open the package, it will be a sticky-wet, staining, semi-solid 1kg clump. Or more likely it will already be that way when you buy it. And despite it dissolves quite slowly, it creates so much heat that you must go even slower. So it takes forever and the FeCL powder will stick to everything. Trying to do this "neatly" is quite a pain. Liquid ferric chloride is easier to handle. If you have easy access to muriatic acid and powdered rust, mixing these together makes the same thing without dealing with "dry FeCL3." And the red rust will dissolve pretty much instantly in the acid.

Muriatic acid alert: In the US, Home Depot is carrying only this stuff by Kem Tek that masquerades as muriatic acid. If you read the ingredients, it lists 15% HCl. And 85% "not suitable for spray adjunctive." Whatever that means, it does not mean water. This stuff ruined my etchant.

Back to OP, ferric chloride keeps fine in a sealed bottle. But if you want to get the most out of it, you also want some muriatic acid. When it slows down, adding a little acid will make it work a bit longer. And when you get a lot of copper in it, aerating it will help. If you get a proper bubbly tank going, you can use it indefinitely; just add some acid and water when it clouds up.

[Mechatrommer]

hi again. my FeCl3 "humid" powder has arrived. and now i mixed 140g powder to 500ml water in plastic container. it got warmer i guesstimate about 40-50degC, even now after 30 minutes its still warm, did i do something wrong? is there some reaction going on that will screw my mix few weeks after this?

[DTJ]

No, releasing heat as it dissolves is normal.