National Airlines asked U.S. District Court here yesterday to bar the Civil Aeronautics Board from further consideration of Texas International Airline's bid to acquire National.

In seeking a preliminary injunction, National contended that further CAB review of the case would "fatally taint" an initial decision by CAB Administrative Law Judge William Daper. Judge Dapper's ruling, which is now being reviewed by the CAB, found bids for National by both Texas International and Pan American World Airways to be anticompetitive.

In its suit, National charged that the CAB failed to fulfill its obligations under the National Environmental Policy Act by not requiring preparation of an enviromental impact statement, had violated various procedural and constitutional due-process requirements by permitting a series of seminars on the general subject of mergers to take place while the case was pending (National argued the panelists were pro-merger) and by allowing some staff members to become "tainted" by ex parte communications.

National sought a preliminary injunction against CAB review of the judge's decision before May 25, the date on which the CAB has said it will instruct its staff on how it intends to handle the bids for National by Texas International and Pan Am.

Phillip J. Bakes, general counsel of the CAB, said yesterday the board just had received the legal papers and he can't comment until he reads them.

Another CAB official suggested the CAB might seek dismissal of the suit on the grounds that National must wait until the board renders its decision, which then is subject to review by the U.S. Appeals Court. He noted also that the CAB had taken up each of the issues raised by the National suit in separate orders.

In other merger news yesterday:

Dow Jones & Co. purchased Bunker Ramo Corp.'s 50 percent interest in a computerized news-retrieval service formed by the two companies as a joint venture in 1971. The price wasn't disclosed. The service provides to distributors a continously updated computerized file of news and information published over the previous 90 days by the Wall Street Journal, Barron's magazine and the Dow Jones News Service.

Southern Pacific Co. and Ticor said they reached final agreement on terms for the previously reported acquistion of Ticor by Southern Pacific. Under the terms, Ticor Shareholders will receive $18 in cash and $22 principal amount of a new issue of Southern Pacific's 10.35 percent debentures due 1994 for each share of Ticor common. Ticor holders have the option of receiving $40 in principal amount of a new issue of Southern Pacific's 9.35 percent restricted notes.

David Wallace, chairman and president of Bangor Punta Corp., announced the signing of an agreement giving Bisping Capital Investment Co., a civil law association in Frankfurt, West Germany, acquisition of a minority stock interest in Bangor Punta. Bisping agreed not to acquire more than 20 percent of Bangor Punta's total outstanding voting securities.