Digital application of colour on textiles 2

In contrast to digital printing, where an image is transferred row by row onto the textile, this process works in a similar way to a plotter. A machine travels along the path to be printed and dispenses the paint onto the textile via a valve. The application of the paint, which can be several millimetres high depending on the settings, creates a 3D effect. By tweaking various parameters, a wide variety of artistic effects is possible.

The printing system is a purchased CNC machine, which is equipped with a print head and adapted for the application. The material tank is located directly on the print head. A piston valve for silicones or a spray valve for emulsion paints can be mounted as a dispensing valve. To apply the paint, the material tank is pressurised and the paint is pressed through the dispensing valve. Optionally, when using the spray valve, the paint can be sprayed by an air jet, the strength of which can be adjusted.

In a first step, systematic test series were performed on a small machine with various settings. The effects achieved and the associated parameters were recorded. The adhesion of the paint to the textiles proved a major challenge, but was greatly improved by adapting the paint formulations.

The large production machine was then put into operation at the industrial partner Jakob Schlaepfer AG, which can print textiles up to 1.5m x 2.2m.

The templates are created in the Adobe Illustrator graphics programme, then converted into the data format required by the machine, using specially developed software. This file is then loaded in the control programme of the machine, which also sets the print speed. Parameters such as print distance, paint pressure or the amount of spray air can be set directly on the printing module. These parameter settings significantly influence the final print image.