A seal pattern including a plurality of main seal lines, a first auxiliary seal line including a plurality of open holes and surrounding the plurality of main seal lines, and a plurality of second auxiliary seal lines positioned corresponding to the open holes. Since the second auxiliary seal lines pass only gas such as air, the main seal lines are protected from being damaged from cleaning detergent or an etching solution during a cleaning and etching process. A hardening agent is used to seal the open holes during an etching process.