Is the patent open first or substantive examination first?

Patents are made public first, and then examined in substance. According to the relevant regulations, after receiving an application for a patent for invention, the patent administrative department of the State Council, after preliminary examination, considers that it meets the relevant requirements, and shall publish it immediately after 18 months from the date of application. Conduct substantive examination within three years from the date of application, and if it passes the examination, issue a patent certificate for invention.