This is a chair to deal with the problem of occupying seats in the library. The body temperature after sitting down will cause the chair surface to change color for a short time, and the color will recover after leaving for a period of time (about 15 minutes), which will serve as the boundary between "short leaving" and "long-term occupying seats", thus solving the problem of fuzzy ownership of public space.

The seats in the library often have the problem of unclear attribution:
The person who occupies the seat may just go to the bathroom and come back to find that the seat has been occupied by someone else.
For those who have just arrived at the library, when they see an empty chair, they are not sure whether to sit on it or not. It may not be long before they sit on it, but suddenly a person says that he has been sitting here for a long time and has just gone out for a while.
Generally speaking, the boundary between "short-term departure" and "long-term seat occupation" of the library location is blurred, resulting in bad use experience and even interpersonal conflicts.

The chair surface of this chair is made of reversible temperature sensitive discoloration material. After sitting down for a period of time, the red mark of "No Parking" will be left on the chair surface and gradually begin to disappear. Before the red mark disappears, it indicates that the seat is already in use and the user can safely leave temporarily. If you leave for too long (more than 15 minutes), the red mark will disappear completely, indicating that the seat here is in a released state, and other students who need it can take their seats.

In this way, it is possible to clarify the use of seats, reduce meaningless waste of occupying seats, facilitate everyone's study in the library, and maximize the use value of seats in the library.