Figure 2
Contact angle of a 3 µl droplet on polished copper samples stored without any cover (uncovered), in a common polystyrene sample box (PS Box) or wrapped in a woodfree tissue (Wrapped). For the wrapped samples a storage time of one day is compared to 10 weeks of storage. The different sample packaging methods lead to different contact angles although all were stored under the same ambient atmospheric conditions. Per storage condition two samples were investigated by applying 6 droplets each. The reference data for normalization is “uncovered/1 day”. Here data normalization was not done sample wise but with the total mean value of the two samples stored for one day uncovered as separate samples had to be used for every storage condition.
