WASHINGTON, Nov 18 (Reuters) - Whirlpool on

Tuesday asked a U.S. trade agency to block the import and sale

of microwaves from rival manufacturers based in South Korea and

China, alleging they copied its patented technology for

over-the-range models.

The complaint, filed with the Washington-based U.S.

International Trade Commission, aims to protect a key market for

Whirlpool, based in Benton Harbor, Michigan. Whirlpool alleges

that South Korean rivals Samsung and LG,

along with China-based Midea and Haier, infringed five of its

patents for "low-profile microwave-hood combination products,"

or LP-MHCs.

In its complaint, Whirlpool said it pioneered technology for the

microwaves, which both cook and provide ventilation.

Spokespeople for Samsung, LG, Haier-owned GE Appliances and

Midea did not immediately respond to requests for comment on the

complaint. Whirlpool said in a statement that it "will not

hesitate to defend our innovation and intellectual property when

a competitor steals a patent-protected design."

"Whirlpool created the LP-MHC product category, and until

the Proposed Respondents began their unlawful conduct, Whirlpool

was the sole provider of LP-MHCs in the United States," the

complaint said.