A mirror cleaned with an alcohol solution is slightly colder right after it is cleaned because the alcohol remains left over the mirror absorbs the heat from the mirror, thereby taking all the heat energy to convert it into vapors.
Explanation
Alcohol solution having a lower boiling point(82 degree Celsius) than water vaporizes quickly than water, taking the heat from the surroundings.
This process in which a liquid state is converted to gaseous state or vapors at given pressure and temperature is called evaporation.