Palladium-free direct plate technology for plating on plastic?

A. Hi Mostafa. Raafat Albendary offers a good deal of info on that subject in thread 10887. Still, developments usually have a period where they are patented or trade secret, so if you've heard of non-palladium activation which is better than what Mr. Albendary is describing, it's probably still proprietary trade secret :-)

Luck & Regards,

A. Dear Mr MOSTAFA
Assalamo Alikom

Mr Ted mentioned my name so I have to respond.
Silver is a good choice for activation if some problems have been solved.
1- silver is not catalytic to electroless nickel when hypophosphite is used as reducing agent.
2- electroless copper has some problems because of highly alkaline solution with pH above 12 makes stability not so good.
3- needs more time in activation
4- some of its solutions are explosive, but on the other hand
1- silver is easy to get anyplace
2- very cheap compared to palladium
3- its solution is a true solution not colloidal as the case in palladium solution
If this is the situation, it really deserves attention to use it as activator.
Many formulas are made to use silver as activator. I will back with details in a second response

regards
Raafat

Dear Mr Ted
DEAR Mr Mostafa

assalamo alikom
I will go through the activation of ABS using silver instead of palladium, but I'm not convinced to use this method nowadays for reasons I will mention later. But education will not harm any one. To use any atom in activation you should make it in the lower valence so you need another metal or reducing agent to make that. Tin takes this role in palladium solution and can also play the same role with silver. You can make tin in separate solution or in one solution with silver but in this case you will need a complexing agent to maintain the metal in solution.

Different solutions and methods to use silver:

1- you can use silver nitrate [as it is] as activator and using the formaldehyde in electroless copper as reducing agent so when you put the activated ABS silver atom will be reduced first then activate the copper to deposit as a black layer in the beginning then give the copper color also. You can use ammoniacal silver nitrate with the same manner but it is explosive, especially when it becomes dry.
Many complexing agents and reducing agents could be used in this bath:
1- carboxy methyl cellulose
2- salts of sulfonates
3- dimethyl amino pyridine
4- galic acid
I think i should stop here in my next response i will give the complete line and kinds of activation baths using silver

Good luck

Raafat

DEAR FRIENDS
AS I mentioned above many complexing agents and reducing agents may be used in this topic
1- complexing
a- carboxy methyl cellulose
b- di methyl amino pyridine
c- galic acid
2- reducing agents
a- formaldehyde
b- borane compounds
c- sulphite compounds
one of the best activators using silver is as follows:
A- 5 g per L CARBOXY METHYL CELLULOSE
B- 4 g per L silver nitrate
C- 1.8 g per L potassium hydrogen borane
as all silver compound container should be opic
this activator works for copper but better to use one gm per L borane compound after to complete reducing silver
line will be as follows:
1- degreasing of ABS
-RINSE
2- Etching in chromic sulfuric [400Gm, 350Gm]
RINSE
RINSE
3-REDUCING CHROME IN BISULPHITE
RINSE
RINSE IN DE-IONIZED WATER
4- ACTIVATION
RINSE IN DE-IONIZED WATER
5-ELECTROLESS COPPER
A- 10 GM PER L copper sulphate
b- 40 gm per L tri ethanol amin
c- caustic soda [affil links] till pH 12
d- 20 ml per L formaldehyde
f- 3 MG CYANIDE OR SULfIDE COMPOUND
rinse
6-electrolytic copper
hope I was clear and I'm ready for any comment

thanks & GOOD LUCK

Raafat

A. Dear Zafar,
many techniques are developed because of the high price of palladium, instability of its solutions and the need to plate other polymers that palladium is not able to plate.
Here in Egypt we developed the activators of Ag, Co, etc.
For E Cu, regarding direct metallization it is not necessary to be Pd free. Direct means No Electroless plating not No activation.
5 years ago we started to develop a new method based on semi conductors layer of metals sulfide able to be plated directly with nickel, copper, etc., without need for EP.
It's well known in Egypt now; it's low cost and simpler than any other techniques.
At first it was not familiar to the platers but now it's OK.

Good luck.

A. assalamo alikom
brother Zafer & brother Mohammad.
Sorry for lateness but I'm not lucky. For a long time I did not come to this site, however:
the metal we can use to make sulfide is all electroplatable metals maybe except chrome --
copper, nickel, tin, cobalt, etc.
Brother Mohammad you deal with direct metallization so no need for electroless nickel. Go directly to electrolytic nickel.
Hope I can help.
Good luck

Raafat

A. alsalamo alikom.
Brother Mohammad, I think there is some problem in your method:
1- after cobalt nitrate as you showed you go to alkali, so nitrate will convert to oxide or hydroxide, so the resultant compound after immersing in sulfide will not be cobalt sulfide. So I think maybe the next procedure will work:
1- cobalt sulphate (for example) will dissolve and be in Amm. complex form by adding Amm. hydroxide to sol. of cobalt sulphate.
2- etched ABS will be immersed in solution
3- water rinse
4- sulfide solution (ALKALI METAL sulfide)
5- water rinse
6- dry
You can repeat if required until you be familiar with timing of every step.
7- electrolytic nickel (Watt's formula)
then any finishing required.

Wth my all respect,
your young brother

Raafat

asalamo alikom

My older brother Mr. Raafat

I have worked with (CoSO4 + AMMONIUM buffer). I haven't done end step: namely DRYING. I will do it again and will report the result to you. Finally, I WILL REACH SUCCESS under your the wise guidance.
Thanks a lot.

A. Brother Mohammad
-- is the ((no news is good news))?
Please advise.

Raafat

A. asalamo alaikom va rahmatolla my brother

Pardon me please , I apologize to you. Because of final exams in university I couldn't continue tests in relation to Pd-free plating but I WILL surely do and report to you.

Very very thanks from your contact.

asalamo alikom va rahmatoola brothar raafat

Today I'm very cheerful for plating ABS with your guidance and instruction. Finally I have learned this method. My point of about you is:

YOU ARE (SIR) & (KNIGHT) & (PAHLEVAAN) PLATING ABS.

THANK YOU SO MUCH.

MOHAMMAD

A. Brother Mohamed
I'm not claiming that I understand completely your words, but I'm only our moslem brother.

Raafat

A. Hi Ganesh,

You may use a water-borne, pre-catalyzed coating which is silver containing to replace palladium catalyst.

Regards,
David