Is the date on the patent certificate the date of issuance?

Yes According to the relevant public information, the effective date of the patent right comes into effect after the announcement of the General Administration of Intellectual Property, which will first review the patents applied by the parties, and issue patent certificates to the parties who meet the requirements, register them in official channels and announce them to the public. Patent literally refers to exclusive rights and interests. The word patent comes from Latin Litteraepatentes, which means open letters or open documents. It is a certificate used by medieval monarchs to issue certain privileges, and later refers to the exclusive rights certificate signed by the British king himself.