Closure for closing a container and for transmitting signals

A cap 2 for closing an at least partially surrounding of a container wall 20 of a container 1 opening 26. The closure 2 has 9 of the opposite a closure body 23 with a fastener thickness 13 and a first portion 8 which faces the container interior and a second region of the container interior and an insulating layer 7. In the insulating layer 7, a signal line 6 for transmitting a signal between the first 8 and second portion 9 is integrated. The signal line in this case comprises a connection point 11 on the first 8 and second portion 9 for connection to connectors 4 and / or electrical components 5 and a Singalleiterbahn 10. The signal line 6 extends at least in sections perpendicular to the closure thickness within the insulating layer. 7