Air Products and Chemicals nominated three heavyweight corporate executives to Airgas’ board on Thursday and wants shareholders to hold an annual meeting every January.

The action, which was expected, is the latest skirmish in the takeover battle between the two industrial gas companies. Air Products went hostile in its bid for Airgas last February, offering $60 per share in cash, or roughly $5.1 billion. Airgas was not available for comment.

Air Products wants to compel Airgas to hold its annual meeting every January. If passed by shareholders, that would force Airgas to hold another meeting as soon as January 2011. Since Airgas has a staggered board of nine directors, such a move would make it much easier for Air Products to gain a majority on the company's board. Airgas shareholders will consider the nominations and proposals at their meeting, on or before September 17.

Air Products nominated John Clancey, chairman emeritus of shipping company Maersk; Robert Lumpkins, chairman of fertilizer producer Mosaic; and Ted Miller, founder of wireless communication provider Crown Castle International. Air Products proposed that any board nominee put forward by Airgas who loses an election would be ineligible to serve on the board for the next three years.

Air Products is also seeking to have all bylaws adopted by Airgas' board after April 7, nullified. Air Products recently extended a tender deadline for Airgas shareholders until June 4. Some Airgas shareholders, as well as Air Products itself, have sued Airgas, hoping to force it to agree to the deal.

A Delaware judge declined to hold the trial quickly, instead opting for a fall trial after Airgas's shareholders meet.