Abstract: The invention relates to a device for monitoring room climate and ventilation behavior in and of inside rooms, having a readable memory unit, a control unit, and a signal generator that are integrated into a window or door handle, wherein the memory unit and/or the control unit is connected to at least one of the following sensors: a sensor that registers the position of the window or door handle (open, closed, or tilted), which may then be stored with the associated time data, or a sensor that measures the room temperature, or a sensor that measures the relative or absolute humidity of the room air such that, upon the room temperature falling below a preprogrammable value and/or upon the room air humidity exceeding a preprogrammable value, the signal generator is activated.

Abstract: The present invention comprises a device for revealing a message or image responsive to temperature changes of approximately 5° F. (3° C.). A thermochromic leuco dye is applied to a surface that is positioned for contact by an outside heating or cooling source. The thermochromic leuco dye reveals an intended message or image when the temperature is changed sufficiently.