* Merck KGaA controls 81.3 pct of AZ Electronic Materials
* To de-list AZ shares in June, keeps offer open for now
* AZ takeover opens up Asia sales opportunities -CEO (Adds CEO comment, background)
FRANKFURT, May 2 (Reuters) - German chemicals and pharmaceuticals company Merck KGaA said it had completed its 1.9 billion euro ($2.6 billion) takeover of Britain's AZ Electronic Materials, a move Merck expects to boost its business in Asia.
Merck said in a statement on Friday it had 81.3 percent of AZ under its control - passing the 75 percent threshold needed - and expected to de-list the company from the London Stock Exchange at the beginning of June.
AZ, which had sales of about 530 million euros in 2013, generates the bulk of its revenue in Asia.
"With AZ, not only will we be able to further expand our presence in the important Asian growth market, but we will also be able to raise our exposure to exciting global megatrends in electronic materials - from smart phones to the most advanced computing devices," Merck Chief Executive Karl-Ludwig Kley said in the statement.
AZ's chief executive Geoff Wild will stay with the company to help with the integration into Merck's Performance Materials division, Merck said, adding that AZ would be operated as a separate business unit during the integration.
The world's largest maker of liquid crystals used in TVs and tablet and smartphone screens, Merck agreed in December to buy AZ for $2.6 billion to expand its range of specialist chemicals for hi-tech gadgets.
Merck gained antitrust clearances in the United States, Japan, Taiwan, Germany and China.
The company had extended its offer seven times while waiting for approval for the deal from competition authorities in China. That approval finally came on Wednesday.
Merck said it still intended to acquire all outstanding shares of AZ and would keep its offer open until further notice. ($1 = 0.7212 Euros) (Reporting by Jonathan Gould; editing by Jason Neely and Elaine Hardcastle)