DIFFERENT METHODS FOR PRODUCING COLOR REPRODUCTIONS ON 3D PRINTED OBJECTS

This article presents two methods of colour printing on programmable 3D structures and their use for practical applications in everyday life. The colour printing was done by direct printing with a flatbed UV inkjet printer and indirect printing by thermally transferring the electrophotographic toner to the 3D printed object produced with the most widely used and affordable material extrusion 3D printing technology. The print quality of the colour reproductions was determined by basic densitometric and spectrophotometric measurements, ink adhesion analysis and image analysis of the printed graphic elements. The research was also extended to the field of 4D printing, where 3D printed objects with flat geometry can be subsequently transformed when exposed to a suitable activation medium. In this case, the direct printing process was used for colour printing, as it allows printing on both sides of the programmable 3D structures compared to the indirect printing process. The advantage of colour printing on a programmed 3D structure is that the flat geometry can be easily printed with colour graphics on the entire surface and later transformed into a new 3D object shape, whereas conventional 3D objects cannot be printed in very inaccessible places due to their geometry. These methods, which use direct or indirect printing techniques to create coloured reproductions on 3D-printed objects, enable the personalisation and aesthetic enhancement of products and can also provide additional interactivity if, for example, QR codes or RFID tags are included. The research focuses on the production of colour-printed smart objects for consumer products