An 18-year-old teen has filed a suit seeking ¥2.2 million ($19,000) in damages from the Osaka Prefectural Government, alleging her public high school demanded that she dye her naturally brown hair black to continue attending classes.

The prefectural government, which runs Kaifukan High School in Habikino, requested the Osaka District Court dismiss the teenager's lawsuit at the first hearing on Friday.

Her mother had informed the school before the teenager started attending that her hair was naturally brown, but teachers repeatedly ordered the student to dye it black, according to the petition the plaintiff submitted to the court.

The student developed a rash and scalp pain after dyeing her hair repeatedly but her teachers continued telling her that her hair was not black enough, demanding she comply or leave the school, the petition said.

During a conversation with her mother, the school said it would even demand that blond foreign students dye their hair black because that was the rule, it said.

The plaintiff said in the petition the school's conduct constituted abuse because she was forced to dye her hair so often that it damaged her health.

She stopped attending school in September last year, according to the document.

Her lawyer, Yoshiyuki Hayashi, said despite the teenager still being a student, her name does not appear in a classroom register for the current academic year, which began in April, and there is no seat for her.

The prefectural education board said rules regarding students' hair are set by each school and declined to comment on the case due to the ongoing lawsuit.

Many Japanese high schools ban students from dyeing their hair, and some demand that those with naturally brown hair submit documents stating their hair is not black.