The "kokai" or "kokai tokkyo koho" is the name given to the published, unexamined
Japanese patent application, as opposed to the "kokoku" or tokkyo koho, the examined and approved Japanese patent application. "Kokai" means "open to the public", or "laid-open". "Kokai" are published eighteen months after the earliest priority date.
Tokukai is another shorthand for "kokai tokkyo koho". Tokkyo (patent) + kokai (open to the public) = tokukai.
Japanese patent law
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