The use of robotic technology in the inkjet printing process could change the dynamic of decorating complex industrial components.
By Debbie Thorp
Hydrographic dipping, also known as immersion printing or water-transfer imaging, can be used on a range of materials including metal, plastic, and glass. A printed film is placed in water and a chemical activator is used to dissolve the film into a liquid and activate a bonding agent. The substrate is pretreated with a base coat and then lowered into the water through the floating ink layer, which wraps around and adheres to the substrate. A top coat is typically applied to enhance durability. This 360-degree-coverage process provides high image quality and substrate flexibility, and is used on many complex shapes – large and small – for full product decoration. Examples include car dashboards, motorbike gas tanks, and bike helmets.
In contrast to such 360-degree coverage, most of the robotic systems using inkjet today (those that are in the public domain) coat or decorate only a part of the multidimensional shape. Full wrapping or full-coverage printing of complex shapes represents the next challenge for inkjet.
Inkjet Printing Using Robotics
To achieve a full 360-degree-printed object, the first step is to create a 3D mesh of the shape. A 3D mesh is a collection of vertices, edges, and faces that provide a virtual description of the shape of a 3D object. For many products, this mesh will be available as an output of the CAD design process but if not, then 3D scanning technology is available.
The next step is texture mapping, which defines the surface texture or color information onto the 3D object. This is the technique that uses software to wrap the image to be printed over the whole object as part of the design process. A wide range of software tools are available to complete this step; many have been developed for the gaming and associated augmented reality industries. Or nonspecialist software programs like Photoshop can also wrap – or texture map – the image onto the shape.
Did you enjoy this article? Click here to subscribe to the magazine.