What do you mean by the expiration date and publication date of various patents?

Invention patents are 20 years from the date of filing, and utility models and appearances are 10 years from the date of filing. You need to pay an annual fee during the period, otherwise it will be invalid.

The publication date is the date when the applicant's application documents are published. For example, the invention patent can only enter the actual trial stage after it is published, while the utility model has no actual trial, and the disclosure is carried out at the same time as the authorization. The publication date has nothing to do with the validity of the patent.