However the second character on the bottle looks more like chou.
This would make the bottle date 1997. Are we reading these poorly written characters correctly?
Did the artist make a mistake?
Is the first character a yi, an easy mistake if your calligraphy is poor and you are painting backwards, making this 1985?
It is really anybody's guess - 1970's, 1985 or 1997. Click here for more information on Chinese Calendars.