After spending years developing new products or technology, many inventors face the further headache of how to promote their creations and put their patents into commercial use.

Wang Zishan, a retiree in Beijing, faced such a problem when he developed a Chinese character input system for cell phones in 2000.

But he recently found a number of parties willing to invest in his patent at the second China (Huaibei) Patent Trading Fair held last week in Huaibei, East China's Anhui Province.

Wang was one of more than 600 patent holders promoting their inventions at the national patent trading fair held by State Intellectual Property Office and the Anhui provincial government.

More than 240 patent transfer and cooperation contracts were signed at the two-day event.

The "patent supermarket" covered sectors including machinery, electronics and information technology, energy and environmental protection, chemical engineering and new materials, biotechnologies and pharmaceuticals, and agricultural processing.

Apart from individual inventors, the fair attracted 18 research institutions and 20,000 visitors.

Wang applied for his patent in 2000, but this was the first time for him to attend such a large-scale national patent trading fair.

To stimulate the commercialization of patents, the State Intellectual Property Office has cooperated with local governments to establish 19 patents trading centers since last year.