A study of the effect of fabric structure and mesh count variation in indirect stencil preparation in a school graphic arts laboratory

In order to choose the best working fabric for screen printing in a school graphic arts laboratory, a representative group of eight polyester fabric samples were tested. The fabrics covered a range of mesh counts from coarse to medium and included fabrics of both multifilament and mono filament types for each mesh count. Both types were of medium grade or quality, XX for the multifilament and T for the monofilament. A specially designed resolution test object was printed by college level students in an introductory graphic arts class using indirect stencils with the sample fabrics. The stencil and five of the fifty copies from each student were inspected to obtain stencil edge definition and print resolution data. The subjects also completed a report sheet to provide information about stencil leakage, plugging problems in the mesh and stencil adhesion failures. Resolution and edge definition data were each subjected to a two factor analysis of variance, the two factors being fabric type and mesh count. Information from the student reports was tallied and plotted in histogram form for comparison of the incidence of printing problems. Results of the experiment showed a high degree of interaction between fabric type and mesh count, making it hard to generalize about effects of the two factors for finest resolution obtainable. Each combination of mesh count and fabric type had to then be compared to see exactly which samples would give specific results. Two fabric samples, 200 mesh and 25XX, gave finest resolution and two others, 135 mesh and 10XX, gave the lowest resolution. No effect was evident for edge definition. Student reports pointed out that the multifilament fabric was less prone to stencil adhesion failures and leakage problems. A great deal of variation due to individual student differences was also found, and because of such wide dispersion, many of the fabrics produced results which were not found to be different, even though some of the meshes were on opposite ends of the range of samples. Another effect of the variation was the occurrence of trends which in a normal screen printing plant would not be expected to happen. Because of this, conclusions could only pertain to a school laboratory environment