obdurate

固执的（形容词）

(adjective) Unreasonably stubborn; not willing to change opinions; hardened against either feeling or logic.

EXAMPLE: Regardless of their hard work or loyalty to the company, the obdurate old owner refused to treat his employees kindly or fairly.

尽管员工们努力工作，对公司忠心耿耿，但是老迈而固执的老板却不愿意好心或者公平地对待他们。