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Nickel plating problem from nickel alto plate

We are in the business of banknote printing.We grow our intaglio plate from nickel alto plate using watts bath.Our problem at times is that during plating we notice cracking of of the grown plate with resultant bending of the plate which grows to make contact with the anode.When this happens there is another under growth and burning of the alto plate thereby leading to loss of the alto plate. Please I will be very grateful if useful suggestions can be offered to help me solve this problem.

R C OTIKA
security printing- Lagos, Nigeria.
2006

Is there any particular reason for using a Watts formulation? If you use nickel sulfamate bath instead, you will have less and more controllable stress, no cracks or separation.

Guillermo Marrufo
Monterrey, NL, Mexico
2006

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Your main problem is that your nickel bath is stressed and out of balance. Watts nickel is not the best type to use for electroforming as it is inherently stressed. I suggest you use a sulphamate nickel bath with an addition of about 0.5g/l sodium saccharin. This will give you both a hard nickel as well as it being low stress and bright. If you insist on keeping your watts bath, you must rebalance the stress reducers to get zero stress.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2006

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Dear sir

We are banknote printers and we use at present watts bath in electroforming our printing plates.Over times we do encounter problems like, hardness, blisters, separation problem burning of alto plates, etc. People have suggested switching to nickel sulfamate bath.For me to convince Management board, what are the advantages of sulfamate bath over the watts bath.This very important for me to convince the management to invest in sulfamate bath.Thanks for your usual co operations.

R C OTIKA
security printing - Lagos, Nigeria
2006