Creative Commons License

Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.


In this work adjustments in the rotogravure printing process are proposed to the varnish water vapor transmission rate (WVTR) aiming to obtain results smaller than 20g/m²/24h. One case study was used for the propositions for improvements, where focused on varnish application process in a gravure printer for an eight-printing unit cartonboard packaging, maximum printing speed of 175 m/min and a 285 g/m² weight cartonboard. The possible variables that influenced the WVTR result were selected from the technical expertise of the people involved in the project, the analysis in the printing process with the application of directed trials using experimental designs (DOE). After realizing forty four trials in a printing machine, were identifying and defined thirteen process adjustment parameters to the best analysis. The project was developed for a cartonboard packaging with a varnish water vapor transmission rate (WVTR) with capacity to pack 500g of a product. The obtained results allowed the proposition for improvements in the studied printing process, used by the print shop to reduce significantly the WVTR used. The records of the results are an average of 25.98g/m²/24h, before the study, and after implementation of improvements there was a reduction to 18.16g/m²/24h in the average of the results, 1.84 g/m²/24h below the target. The WVTR standard deviation was from 8.95 g/m²/24h to 2.22 g/m²/24h, thus presented better process stability. There are large number of solvents and resins, which can be applied in rotogravure machines, and each has its specificities. Based on all the expertise acquired from the study, it is possible to propose a line of work to find precise adjustments in the varnish application. Therefore this study addresses an important approach to the future of sustainable packaging, which contains little information in technical literature.