What is the process of patent application, chemical invention patent?

Chemical technology can only apply for invention patents, and the application process of invention patents specifically includes: preparing application documents (10-30 days) → submitting application (within 3 days) → preliminary examination of invention patents → publication → substantive examination of invention patents → rejection or authorization → payment of rights and interests fees → issuance of patent certificates. The overall time needs about 2-4 years, mainly depending on the substantive review process.