Unilever made its biggest acquisition in China when it bought 55 percent of Qinyuan Group, a Chinese water purification company, that will boost the Anglo-Dutch consumer goods giant's business in this sector globally.

"We are delighted to make this strategic investment (in Qinyuan),'' said Paul Polman, global head of Unilever, in a statement yesterday.

"This deal will more than double the size of our water purification business and will bring together complementary technology... all under the Unilever umbrella," Polman said.

He said the deal is the company's biggest acquisition in China for more than 10 years.

The companies, however, did not disclose the acquisition price.

Marijn van Tiggelen, executive vice president of Unilever North Asia, said the Anglo-Dutch giant's investment in Qinyuan Group could help China become a world-class hub for water purification technology and production.

The water purifier market may expand 20 percent annually in China in the coming years on people's growing income and concerns over water safety, van Tiggelen said.

Unilever predicted the water purifier business in China to contribute 10 percent of its local revenue in the future.

Set up in 1988 in Ningbo, the Qinyuan Group's sales of home use water purifiers hit 1.2 billion yuan (US$196 million) in 2013, giving the company 20 percent market share.

After the acquisition, Qinyuan will operate independently.