## 3 Experimental Results  
The acquisition of the topography maps using atomic force microscopy allowed us to observe significant morphological changes due to exposure to the set of previous conditions (Figure 6). While the reference surface was relatively flat, with no discontinuities, and the presence of large (up to 1 \(\upmu\)m in diameter) silver particles could be noticed, sample B reveals the first signs of degradation, such as cracks and pinholes. On the other hand, in the case of sample C, a vast reduction in the volume of the material is visible, showing advanced degradation of the acrylic matrix. In order to compare the morphological changes in a quantitative fashion, the roughness parameters were calculated. The acquisition of several sets of data for each sample allowed us to calculate the average value and the distribution of the parameters, providing insights into the homogeneity of the surfaces. The following parameters are shown in Figure 7 (Supplementary Materials Figure S1): average roughness (S\({}_{\text{a}}\)), root mean square roughness (S\({}_{\text{q}}\)), peak-peak value (S\({}_{\text{z}}\)), and the surface area ratio (S\({}_{\text{dr}}\)). A significant increase in all of the presented parameters is clearly visible. A rapid increase in S\({}_{\text{z}}\) is related to the appearance of the first cracks and pinholes penetrating the volume of the film. The vertical bars show the standard deviation within the set of measurement data. A further increase in this parameter has smaller dynamics as the process switches to the volume loss. It should be noted that the standard deviation bars reveal that the spatial non-homogeneities of the surface are smaller than observed roughness changes. This important information allows us to claim that the measurements are meaningful and can be used for the analysis. Additionally, the exceptionally large SD bar in S\({}_{\text{z}}\) for the second sample shows that at a certain point of deterioration, quite large cracks appear in the surface (visible in Figure 6), which initiate the mechanical degradation of the surface. One of the advantages of the AFM method is the measurement of the mechanical properties of the surface. Figure 8 (Supplementary Materials Figure S2) shows the changes in stiffness and adhesion measured using the force spectroscopy technique. The stiffness increase, along with the adhesion reduction, revealed the tendency of the film to peel off after the doubled exposure. This phenomenon was also confirmed by the macroscopic observation. Further analysis revealed that UV exposure causes further polymer networking, hence hardening. Figure 6: Examples of the topography images acquired using atomic force microscopy (AFM). Samples (**a–c**) from left to right. While the durability of the surface is one of the most desired properties, some elasticity is also necessary to avoid the presence of too much tension between the substrate and the film. Therefore, one can expect a complete dysfunction of the film once similar conditions are present in real applications. Such a conclusion can be considered as the basis of the disqualification of the investigated film. This stage of the experiment allowed us to notice the expected lifetime of the antibacterial film. The exploitation period causing the exposure conditions simulated for sample B could be acceptable, but the double-time use would cause damage to the film. On the other hand, the pull force (visible also in Figure 3), which reveals the adhesion force present between the surface and the scanning tip, decreased while exposure was applied (Figure 9). (Supplementary Materials Figure S3). The observed behavior may indicate a reduced ability of the film to stick to other surfaces, which, in connection with other processes, can cause the film to detach from the substrate [30]. Figure 8: The comparison of stiffness changes for investigated samples. Figure 7: The roughness parameter comparison for investigated samples.