Details:
Summary:
Flexographic plates are commonly made from photopolymer material by photographic process, which involves film. Digital platemaking technologies have been developed due to rapid growth of flexographic printing and some have involved the use of rapid prototyping (RP) technologies. There are two types of RP, additive and subtractive. Additive technologies, such as 3D printing (3DP), fused deposition modeling (FDM), stereolithography (SLA), selective laser sintering (SLS), build a model by successive addition and cohesion of horizontal cross-sections. Therefore, they can be used to build a plate directly, or build a matrix which is filled with liquid photopolymer and exposed to make a plate. Subtractive technologies, such as computer numerical control (CNC) machining, laser machining, work by removing part of the model. Therefore, they can be used to remove the non-printing areas of a plate. In this study, three RP technologies were applied in flexographic platemaking. A 3D printer was used to build matrices with powder, which were then infiltrated in five different ways to improve durability and surface finish. The matrices infiltrated by wax and low viscosity cyanoacrylate had better release properties. The plates made from a wax-infiltrated matrix had best surface finish. An FDM machine was also used to make matrices by extruding acrylonitrile-butadiene-styrene (ABS) plastic. The matrices were filled with liquid photopolymer and exposed by UV light to make plates. A laser engraver was used to make plates from cured sheet photopolymer by removing the non-printing areas. A plate was also made from sheet photopolymer through photographic process. The minimum line width was 0.0055" for the laser engraved plates, 0.007" for the plate made through photographic process, 0.01" for the plates made with the matrices built on the FDM machine, and 0.02" for the plates made with the matrices built on the 3D printer and infiltrated by wax and low-viscosity cyanoacrylate. All the plates were printed on a flexographic press. The print quality of the laser engraved plates and the plate made through photographic process is better than that of the plates made with the matrices. The results indicate 3DP and FDM should be limited to producing flexographic matrices where fine detail is not needed, whereas direct laser engraving of a plate may result in fine detail.