Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
The authoritative public forum
for Metal Finishing since 1989
-----
Palladium-free direct plate technology for plating on plastic?
March 13, 2022
Dear David:
Please can you post full process of silver catalysis for ABS activation instead of palladium process?
Reg
Plater - Bangladesh
by G. G. Gawrilov
on AbeBooks
or eBay or
Amazon
(affil links)
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,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 2022
March 18, 2022
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
- Riyadh Saudi Arabia
March 19, 2022
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
- Riyadh Saudi Arabia
March 20, 2022
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 ⇦liquid caustic soda in bulk on
Amazon [affil link]
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
- Riyadh Saudi Arabia
⇩ Related postings, oldest first ⇩
Q. Dear Sir;
I have read some where that there is a new development in plating of ABS plastic. In this process palladium activator is not used and also EN is not applied. Instead of EN they use ammoniacal hydroxyl ion etc. It makes the plastic conductive for subsequent electroplating.
Can any worthy reader refer to some book or literature in this regard?
Thanks
Plating shop - Lahore, Pakistan
2007
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.
plastic electroplating - Cairo, Egypt
Q. Dear Raafat,
Thanks for your response. You have mentioned the use of some metallic sulfide in place of EN. Can you please help me to explain what sulfide should be used. Is there any complexing agent, buffer element or reducing agent?
Thanks,
- Lahore, Pakistan
2007
Q. Dear Rafaat
I sincerely thank you for all your complete written answers. I'm testing a method of direct metallization (Pd-free) with:
1. Co/ NH3
2. sulfidation
3. electroplating Ni.
I have problem in amounts of any step. Can you help me? Thank you
mohammad reza ebrahimpourshibe - qazvin, iran
November 15, 2012
November 28, 2012
Q. Dear sir
I have a problem in activating ABS parts. I try to activate ABS by following steps:
1.CrO3/H2SO4
2. Co/NH3 solution
3. Alkali solution
4. Sulfidation
5. Ni electroless (with reducer agent: hypophosphite sodium).
But I cannot deposit Ni on activated ABS. Can anyone help to me?
I sincerely thank you.
- Qazvin, Iran
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
- Riyadh, Saudi Arabia
December 5, 2012
Salamon likom va rahmatolla, Mr. Raafat.
Very very thanks for your reply.
Q. Next of sulfidation, parts go to bright Ni bath but unfortunately no deposition on it. At first I increased voltage from 1 volt (for 1 min) to 2 volt (for 1 min) and 3, 4 volts for 4 min step by step, next I increased voltage to 5 volt. I am confused. Do I need to a special Ni bath (for example sulfamate or ...?).
Thank you very much
- Qazvin, Iran
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
- Riyadh, Saudi Arabia
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.
- Qazvin, Iran
A. Brother Mohammad
-- is the ((no news is good news))?
Please advise.
Raafat
- Riyadh, Saudi Arabia
December 18, 2012
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.
- Qazvin, Iran
December 20, 2012
Q. asalamo alikom va rahmatollah brother raafat
Excuse me for long delaying my reporting to you, I worked and result was positive but it was not satisfactory. I think that I must change amount of sulfide because of a bit of surface of ABS electroplated. At the present, I want to find optimum amount of sulfide. As soon as find it, I will report to you again.
With much thanks,
mohammad
- Qazvin, Iran
January 28, 2013
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
- Qazvin, Iran
February 19, 2013
A. Brother Mohamed
I'm not claiming that I understand completely your words, but I'm only our moslem brother.
Raafat
plastic electroplating - Riyadh, Saudi Arabia
February 22, 2013
Electroless Nickel Plating on ABS Plastic without Palladium
February 4, 2014Dear sir,
We have been interested in plating electroless Nickel on ABS plastics.
We have tried many different pretreatment methods such as chromium etching, tin and Pd activation. though Pd is working nicely we are not interested to use it because it is very costly.
Can any one suggest which alternative option will be apt for the EN plating on the same material?
Please advise us a suitable solution to solve this problem.
Thank you,
With best regards,
- Bangalore, Karnataka, India
A. Hi Ganesh,
You may use a water-borne, pre-catalyzed coating which is silver containing to replace palladium catalyst.
Regards,
David
David Shiu
- Singapore
February 6, 2014
Q, A, or Comment on THIS thread -or- Start a NEW Thread