The Finishing Alliance member joins partner companies Duplo and Renz, who already sponsor the scheme.
PrintIT! will use The Finishing Alliance's London Calling 3D event at the BFI Imax this week (21-22 September) to launch its supporters package.
Proskills deputy chief executive Tom Bowtell said: "We are delighted to have support from all three members of the Finishing Alliance, especially in the week that we launched the new PrintIT! Supporters initiative."
Any printer with a turnover of less than £5m can sign up to the scheme for £200 a year. Subscribers will be able to use PrintIT! branding in their promotional material, and also have access to work with local schools via the PrintIT! twinning programme.
A raffle will be held at the London Calling VIP event, with proceeds donated to PrintIT!.
Duplo managing director Tony Lock, who is also the current PrintIT! chairman, said: "PrintIT! has excellent backing from the print and paper industries, but if we are to make it sustainable we need more support so I would urge printers and suppliers to put their full support behind PrintIT!."