Dow Chemical, which owns Morton International's parent company Rohm and Haas, announced it sold the firm for $1.68 billion (1.25 billion euros) to German fertilizer and chemical maker K+S.

"We are pleased that we reached an agreement with K+S at an attractive value in such a short period of time," Dow CEO Andrew Liveris said in a statement.

'Umbrella girl'

Morton is a 160 year old company known for its iconic "Umbrella Girl" logo, and it is North America's largest salt producer with annual sales last year of $1.2 billion, Bloomberg news service reported.

K+S Chief Executive Officer Norbert Steiner says the company is expanding in North America to gain markets for salt used in the de-icing industry, and for food.

The acquisition will double the percentage of revenue the Kassel, Germany-based company generates from salt to about 26 percent and cushion swings in potash demand.

"This is a further milestone in our expansion strategy," CEO Steiner told Bloomberg. "The Umbrella Girl is one of the 10 most recognized brands in the US along with McDonald’s and Coca-Cola."

The deal makes K+S the world's biggest salt producer.