It is not illegal to print red flags on cultural shirts. For large-scale commercial production, it is necessary to clearly avoid trademark and advertising issues and avoid breaking the law. At the same time, if the T-shirts produced are used by others to do illegal things, you need to be careful to bear the relevant legal responsibilities. According to Article 18 of the "Flag Law of the People's Republic of China": "The national flag and its patterns shall not be used as trademarks and advertisements, and shall not be used for private funeral activities."

The design pattern has Notes on national flags

The product design can have the flag of another country as a pattern. Foreign flag patterns cannot be used as trademarks unless the country agrees. Article 18 of the National Flag Law stipulates that the national flag and its patterns shall not be used as trademarks or advertisements, nor may they be used for private funeral activities. Article 10 of the Trademark Law stipulates that the following signs shall not be used as trademarks.