* Trump's threat of new tariffs against China sours mood
* Komatsu hits 8 1/2-month low, Shin-etsu Chem 9-month low
* Rare Japanese unicorn Mercari traded at 66 pct above IPO price
By Hideyuki Sano
TOKYO, June 19 (Reuters) - Japanese stocks slid on Tuesday after U.S. President Donald Trump's new threat to impose a 10 percent tariff on $200 billion of Chinese goods, escalating a tit-for-tat trade war with Beijing.
The Nikkei share average fell 0.9 percent to two-week lows of 22,482.89, slipping further from last week's high just above 23,000. The broader Topix declined 0.7 percent to 1,758.35, hitting its lowest levels since June 1.
Trump's remarks came just days after he said on Friday he was pushing ahead with a 25 percent tariff on $50 billion worth of Chinese products, which immediately prompted Beijing to respond in kind.
"Concerns about trade frictions between the U.S. and China intensified after Trump's comments," said Hideyuki Ishiguro, senior strategist at Daiwa Securities.
"Although the latest data showed Japanese exports were strong in May, if China's exports to the United States slow down, that would slow down capital spending in China," he said.
With Washington and Beijing appearing increasingly headed toward open trade conflict, investors dumped shares of companies geared to global trade and Chinese demand.
Shin-etsu Chemical fell 2.9 percent to nine-month lows, having fallen almost 15 percent over the past month.
Construction equipment maker Komatsu fell 1.6 percent, hitting an 8-1/2-month low.
Despite the spectre of intensifying protectionism, the current strength of the global economy is also prompting some investors to flock to shares that are perceived to have limited exposures to a trade war.
Tokyo Disney Resort operator Oriental Land Corp hit a record high while Central Japan Railway scaled 3-1/2-year peaks, before giving up gains on profit-taking. They both ended morning trade down 0.2 percent.
Flea market app operator Mercari Inc's started trading at 5,000 yen, 66 percent above its IPO price of 3,000 yen in its Tokyo stock market debut, underscoring strong investor appetite for a rare Japanese unicorn.
"We have a rush of IPOs, a total of 11 by the end of month. While major shares are being hampered by trade concerns, investors' focus could shift to start-up shares," said Masayuki Doshida, senior market analyst at Rakuten Securities. (Editing by Shri Navaratnam)