Other Western coloring books have reached China recently, including a series for adults from the UK and a French book on how to relieve stress through coloring.

"There weren't such books in China before, but the industry has paid great attention to them since last year," says Yuan Jingya, planning editor of the Guangxi Science and Technology Press. Her company has imported the UK series.

The coloring book's main selling point is its ability to help people relax, Yuan says. It is based on the research of art therapy by Carl Jung, the founder of analytical psychology, that contends one can alleviate the pressures of daily life if one focuses on sketching.

Yuan says the UK series of coloring books for adults sold more than 200,000 copies in China last month, fueled by increasing domestic demand and little homegrown supply.

"We also plan to make original Chinese coloring books in the near future," Yuan says.

There are many art designs in Chinese culture that are ideal for such books－from the drawings of mythical animals on bronze to thangka (traditional Tibetan Buddhist paintings).

Wei Ling, an editor at Xiron Publishing, which imported the French art-therapy series into China, says the popularity of coloring books will grow because they cater to the needs of urban Chinese.