# Elimination of the Solid Graininess Issue with Different Micro-Pattern Structures at Flexo Printing
## 3 Results and Discussion  
The different behaviors of the different types of micropatterns created on PVC and PET printing substrates are determined by measured values. These determined values are presented below, supported by visuals. The values obtained as a result of the measurements of eight different micro-patterns created are given in Table 3. Values marked in green are the best results; values marked in orange are the worst result. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Substrate**} & \multicolumn{3}{c}{**PVC**} & \multicolumn{3}{c}{**PET**} \\ \hline
**Tape** & **Medium-Hard Tape** & **Medium-Soft Tape** & **Medium-Hard Tape** & **Medium-Soft Tape** \\ \hline  & SID & Graininess & SID & Graininess & SID & Graininess \\ \hline _Non-Pattern_ & _1.52_ & _0.15_ & _1.41_ & _0.27_ & _1.21_ & _0.21_ & _1.26_ & _0.12_ \\ \hline Pattern 1 & 1.55 & 0.13 & 1.61 & 0.14 & 1.29 & 0.19 & 1.4 & 0.08 \\ \hline Pattern 2 & 1.64 & 0.06 & 1.55 & 0.16 & 1.31 & 0.19 & 1.4 & 0.07 \\ \hline Pattern 3 &According to this table, Pattern 3 with medium-soft tape on PVC printing substrate has a solid ink density higher than other patterns and a non-pattern surface, and the graininess is reduced. In Pattern 4, higher solid ink density is achieved in both PVC and PET printing substrates, and less graininess is achieved compared to the SID values that do not contain micropatterns. The printed areas magnified at 60\(\times\) with a microscope in solis (100%) are shown in Figures 6-14. When SID images without micro-pattern are examined, edge voids in the solid areas and rough appearance on the surface are observed. Graining is observed in the solid areas. In the PVC print substrate, shadowing occurred at points at 50% screen tone values. In PET printing material, rings are seen within the dots. These rings are caused by poor ink transfer to the solid areas. When the images in Figure 7 are examined, it is seen that although there is a slight increase in density in the solid areas of the micro-pattern 1 application compared to the non-pattern SIDs, there is no visual difference. It does not create a visible difference in dot areas, as it is on the solid areas. Figure 6: Non-pattern print results. Figure 7: Pattern 1 print results. When the images in Figure 8 are examined, it is seen that there is no significant difference in the density and ink laydown of the micro-pattern 2 application on the solid areas compared to the non-pattern SID and micro-pattern 1. It has been observed that the shadowing at the dots has decreased in the screening areas. When the images in Figure 9 are examined, improvements were observed at the solid area density and ink laydown of the micro-pattern 3 application, which created on the solid areas compared to the non-pattern SID and micro-patterns 1 and 2 application. Especially in the prints made using PVC-printed Tesa 72,022 plate mounting tape, very clear results were obtained in both solid areas and screened areas. When the images are examined according to Figure 10, it has been determined that the micro-pattern 4 application created is extremely successful in ink transfer of prints, regardless of the substrate material, both on the solid areas and in the screened areas, compared to all other developed micro-patterns on the solid areas. It has been determined that the trail edge void problem that occurs in the edge area of the printed solid areas, which is commonly encountered in flexo printing, has been completely eliminated. Figure 8: Pattern 2 print results. Figure 9: Pattern 3 print results. Figure 11: Pattern 5 print results. Figure 12: Pattern 6 print results. Figure 10: Pattern 4 print results. Figure 16: Graininess intensity for each pattern (medium-soft tape). Figure 17: Graininess intensity for each pattern (medium-soft tape). Figure 6:0 Printed solid ink density values. Figure 6:1 Non-pattern graininess analysis. Figure 6:2 Graininess intensity for each pattern (medium-hard tape). Figure 6:3 Pattern 2 graininess analysis. Figure 6:4 Pattern 1 graininess analysis.