Japanese chemicals, resins and fibers group Kuraray has reached agreement to buy US activated carbon company Calgon Carbon for $1.1 billion.

Under terms of the deal, Kuraray will pay Calgon’s shareholders $21.50 per share in cash, which represents a premium of more than 60% to the Pittsburgh group’s stock price of $13.20 the day before the merger was announced on Sept. 21.  Both companies’ boards of directors have unanimously approved the acquisition.

The transaction is expected to close at the end of December, after which Calgon will operate as a wholly owned subsidiary and serve as the headquarters of a global business providing filtration media, services and equipment to water-treatment customers.

Calgon employs around 1,400 people and operates 20 facilities in Europe, USA and Asia. It posted a net income last year of $13.8 million on sales of $514.2 million.

Randy Dearth, Calgon’s CEO, said the merger will make his company part of a much larger, stronger global company with the resources to support its businesses well into the future.

Calgon paid $153 million for Arkema’s activated carbon business last year, adding wood-based activated carbon to its leading coal-based portfolio and boosting its platform to invest in the emerging markets of Asia and South America.