This is Neptis sappho! P. hylas can you find only in Okinawa.
At hylas, the red circled area is more clearly delimited.
The spots 6-9 from hylas are more uniform in size shape and orientation.
On Honshu you find also Neptis pryeri, philyra, alwina and in the nord part rivularis. Have a look at Bestimmungshilfe.
Sorry about my englisch, its like Google translatet.