TOKYO, Oct 20 (Reuters) - Japan’s benchmark 10-year bond yields hit 6-month highs on Wednesday, tracking U.S. Treasury yields higher, as global stock markets gained on rising optimism about corporate earnings. U.S. stock indexes closed higher on Tuesday with the biggest boosts from the technology and healthcare sectors as investors appeared to bet on solid quarterly reports. The 10-year JGB yield rose to 0.095%, its highest since April 13, before closing up 0.5 basis point at 0.090%. During the Asian trading hours, the 10-year U.S. Treasury yield climbed as high as 1.673%, a level last seen in May. It last stood at 1.650%. The U.S. Treasury yield curve widened on Tuesday, as investors unwound recent flattening moves after some global central bank officials dampened expectations of near-term tightening in their respective countries. The 20-year JGB yield rose 1.5 basis points to 0.485% and the 30-year JGB yield increased 0.5 basis point to 0.695%. The 40-year JGB yield was flat at 0.760%. The yield on two-year JGBs remained at minus 0.120%. The five-year yield was unchanged at minus 0.075%. Benchmark 10-year JGB futures fell 0.02 point to 151.32, with a trading volume of 25,957 lots. Reporting by Tokyo markets team; Editing by Ana Nicolaci da Costa