Chinese consumers are known to be fond of products made in Japan, and Amazon Japan has stepped in to capitalize on it.

Without much fanfare, the Seattle-based online retail giant's Japanese unit rolled out a website in Mandarin in June to tap into a billion-dollar market.

"Explosive purchase (bàomǎi)" is a Japanese coinage that describes the pent-up buying habits of Chinese tourists visiting Japan primarily to buy large amounts of goods to take back home.

Chinese visitors spent 80 billion yuan ($1.2 billion) in Japan in the past year, according to Japanese tourist statistics. China's Ministry of Commerce says Chinese shoppers snapped up 1.2 trillion yuan worth of goods overseas in the past year.

"Looking at Amazon alone, cross-border sales are now nearly 25 percent of all third-party units sold on Amazon, and its coverage in 172 countries reached 189 markets last year," Michelle Tsai, head of marketing for China (in Shanghai) for channeladvisor.com, an e-commerce solutions provider based in North Carolina, told China Daily.

"Not satisfied with the homegrown success, Japanese brands are following the scent of money and are eager to tap the vast Chinese domestic market, and the quickest way to do it is through online marketplaces," she said. "With the significant demand for Japanese products in China, I imagine cross-border trade into China (will) yield significant dividends for Amazon."

The most popular Japanese brand is Zojirushi, maker of rice cookers, according to Ctrip. Over-the-counter medicines and cosmetics, however, are the top sellers (rice cookers are in fifth place).

Japanese medicines are known for their quality and safety, and Chinese are fond of them because they combine modern medicine with ingredients found in traditional Chinese medicine.

Amazon Japan also offers reduced shipping rates to mainland homes and businesses. Bloomberg.com said Amazon.com Inc is evolving in Asia to find new revenue streams from China, where Alibaba Group Holding Ltd dominates.

E-commerce demand from China to Japan is projected to almost triple to 2.34 trillion yen ($22.5 billion) in 2019, according to Japan's Ministry of Economy, Trade and Industry.

"The opportunity is huge," Jasper Cheung, president of Amazon Japan, told bloomberg.com. "We have already increased the selection that we can export by the millions over the last several weeks."

Some Chinese shoppers who seek authentic Japanese products are concerned about product safety and counterfeits on some web stores in China.

Those concerns have helped send more than 3 million Chinese tourists to Japan this year, up over 40 percent, and are boosting demand for Amazon.co.jp, Wandou and other outlets selling Japanese goods, according to bloomberg.com.