The divestment follows poor financial results from the unit in 2005 and a growing trend in the chemicals market, where many firms are abandoning their pharma specialty chemicals business, as higher raw material and energy prices eat away profits.
Last year Avecia sold its pharma custom synthesis business to Nicholas Piramal India for £9.5m (€14m), while Rhodia passed its Pharmaceutical Solutions unit on to India's Shasun Chemicals & Drugs.
Clariant had tried to restructure PFC, which was the only unit within the company not showing growth, by slashing costs and cutting jobs.
But the Swiss company has already gone through a SFr310m cost-saving exercise, losing 4,000 jobs or 15 per cent of its staff, and so has little appetite for more painstaking reforms.
"The market for non-regulated materials - pharma as well as all other industries - has seen intense competition over the last few years as well as significant overcapacities due to large investments in the late 1990s," Ralf Pfirmann, PFC's global business director, told In-PharmaTechnologist.com.
"PFC is only operating in the regulated field of hi-tech building blocks, current good manufacturing practice (cGMP) intermediates and active pharmaceutical ingredients (APIs), and offers excellent customer collaboration, technologies, reliability and regulatory compliance, so it is bound for profitable growth as Clariant has supported the business since 2002 to continuously pursue a consistent strategy built on stability to enhance customer trust."
Towerbrook also believes PFC, which made sales of approximately SFr210m in 2005, is well positioned for growth, pointing to its recent selection by Roche to produce a shikimic acid derivative, known as epoxide, for Tamiflu.
It claims the new autonomous entity will be one of the world's largest businesses based solely on pharmaceutical fine chemicals, with 800 employees and manufacturing plants in Italy, Germany, the UK, and the US.
"As a supplier to the pharmaceutical industry, PFC is in an excellent position to benefit from the increasing trend towards outsourcing to specialist providers," James Harrison, a managing director of TowerBrook, said in a statement.
"Together with management, we plan to grow the business through new capital investment and through appropriate acquisitions."
PFC is now likely to have a new name by July and both Clariant and Towerbrook insist the transition will not affect clients, as there will be continuity in management, customer interfaces and operations.
The agreed selling price of SFr110m includes an earn-out participation of SFr40m which will be paid in two years' time.
Towerbrook already has experience in managing specialty chemical firms, having acquired PolymerLatex, a German synthetic latex producer, from Bayer and Degussa in 2003.
It is also not the first time Clariant has divested a business not in line with its "strategic focus"; Electronic Materials - now AZ Chemicals - and Clariant Acetyl Building Blocks were sold for similar reasons.