TRANSMITTER APPARATUS FOR TRANSMITTING TIRE INFORMATION, AND TIRE INFORMATION MONITORING SYSTEM

Provided are a transmitter apparatus that can appropriately detect and transmit tire information, such as air pressure information about a tire, even when a puncture in the tire is repaired by using a puncture repairing agent, and a tire information monitoring system. The transmitter apparatus used in the tire information monitoring system is provided with: a sensor detecting the state of gas with which a tire cavity region is filled as tire information; a transmitter transmitting the detected tire information; and a wall covering the sensor and the transmitter. The wall forms an internal space divided from the tire cavity region and a communicating hole penetrating the wall and providing communication between the internal space and the tire cavity region. An inside opening part of the communicating hole in a surface of a housing facing the internal space is formed with a greater opening area than an outside opening part of the communicating hole in a surface of the housing facing the tire cavity region. In a surface of the wall facing the communicating hole, a recessed part which is recessed toward the surface of the housing including the outside opening part is formed.