An employer of labor may adopt a badge, or other insignia of identification, to be worn or displayed by the employees for the purpose of identification while upon the premises of the employer and may post a notice of the adoption of such badge, or insignia, near the main entrance of such premises. Such employer may deposit with the department of labor a replica of such badge or insignia, and such department shall, if such badge or insignia be distinctive, issue to such employer a certificate authorizing the use thereof for the purposes of this section. Any person who, after the approval and adoption of such badge, or insignia, without authority or permission of the employer adopting the same, wilfully wears such badge or displays such insignia, or any facsimile or any imitation thereof, or uses the same to obtain admittance to or remain upon the premises of the employer, is guilty of a misdemeanor.