Haines left Premier Paper in May after it was acquired by independent merchant Beswick Paper for £19m.
Fedrigoni's current UK sales director Simon Shenton is moving to the company's Italian head office to take up an export position.
Haines said: "It is very exciting to join an innovative company such as Fedrigoni which, despite difficult trading conditions, continues to invest in marketing and promotional activity to stimulate demand."
Over the next few months, the company said it will continue to focus on selling its products and is opening a London showroom later this month that will also act as a base for Fedrigoni's enlarged team of paper consultants.
Haines said: "In the longer term, we plan to strengthen our presence with designers and other specifiers while forging closer relationships with other UK merchant partners.
"The company will seek to maximise the opportunities that have inevitably risen following the continued consolidation and closure of speciality paper manufacturers."
Haines has previously said his departure from Premier Paper, along with financial director Robert Lockwood and marketing manager Abi Doyle, was very amicable and that he had a good working relationship with the company.
Premier Paper was acquired by Beswick Paper, after former owner Antalis was forced by the European Commission to sell it off in order to complete its acquisition of Map Merchant Group.
Based in Northampton, Fedrigoni has 23 staff and a £10m turnover. The company's group turnover is £480m and it covers the text, cover and niche markets.
Former Premier Paper MD starts sales role with Fedrigoni
Premier Paper's former managing director Fred Haines started his role as sales director of paper manufacturer Fedrigoni on 1 September.