China will send a high-level delegation next month to press its case for membership in the General Agreement on Tariffs and Trade. Membership might help China broaden its chemical and pharmaceutical protection.

GATT, based in Geneva, referees world merchandise trade. China was a founding member but dropped out after the Communists seized power in 1949.Rejoining GATT would bring some benefits to China but also would require a number of conditions, including minimal state interference in the economy and markets, a convertible currency and acceptance of GATT's broad free-trade rules.

A new report on China's economic and trade reforms will be submitted at talks with GATT beginning Feb. 13, according to Tong Zhiguang, a vice-minister of foreign economic relations and trade. He will lead the deputation of a score of officials from various ministries and departments.

China has submitted a number of papers in support of its application. It appears to be moving toward a convertible currency, insists it will honor overseas intellectual property and periodically tries to reduce state control of some industries.

Separately, but certainly not coincidentally, China's chief patent official said a new law should go into force Jan. 1, 1993, extending protection to chemical and pharmaceutical products.

Gao Lulin, who participated in the recent Sino-American talks on property rights, acknowledged "many inconveniences" had arisen from failure to protect such items. The new draft must be approved by the National People's Congress, but that is largely a matter of executive fiat.

Mr. Gao said as well as providing protection where none exists, the new law will extend coverage for inventions to 20 years from the current 15 years. It will also broaden coverage on production processes to include end products, he said.

China reported a total of 4,645 overseas patent applications last year. The largest number came from the United States, Japan and Germany, but official figures so far available don't give a breakdown.

Mr. Gao made a point of linking improved patent rights to the application for GATT membership and to generally increasing China's trade.

In its new submission, China will cover what's called transparency in trade policies, commitment to market access, "substantial" tariff reductions and a continuing reduction in licensing, according to the trade official.

"I hope the coming session will conclude examination of our foreign trade regime(n) and begin talks on the specific issues of re-entry," Mr. Tong said. He pledged to submit a further 15 documents on transparency, which essentially means foreigners knowing all the rules and regulations.

Mr. Tong said the new papers will include information on import and export licenses, quality inspections and items still subject to state-set prices. He reiterated that China stopped subsidizing exports early last year, something foreign traders and analysts say is only partly true.

"We will do our utmost to make trade concessions and facilitate foreign exports into China's domestic market," Mr. Tong said.