Hydrographics or HydroGraphics, also known as immersion printing, water transfer printing, water transfer imaging, or cubic printing, is a method of applying printed designs to three-dimensional surfaces. The hydrographic process can be used on metal, plastic, glass, hard woods, and various other materials. Also commonly known as "hydro dipping".
The Water Transfer Printing process is extensively used to decorate items that range from entire all-terrain vehicles and car dashboards, to small items like bike helmets or other automotive trim. Films can be applied to all types of substrates including plastic, fiberglass, wood, ceramics, and metal. For the most part, if the item can be dipped in water and can be painted using traditional techniques then the hydrographic printing process can be used.
In the process, the substrate piece to be printed is pre-treated and a base coat material is applied. A polyvinyl alcohol film is gravure-printed with the graphic image to be transferred, and is then floated on the surface of a vat of water.
An activator chemical is sprayed on the film to dissolve it into a liquid and activate a bonding agent. The piece is then lowered into the vat through the floating ink layer. The ink layer along with the polyvinyl alcohol backing then wraps around and adheres to the item. The adhesion is a result of the chemical components of the activator softening the base coat layer and allowing the ink to form a bond with it.
After removing the piece from the water, a top coat is applied to protect the design. With multiple prints, hydrographics printing can achieve full 360° coverage of the part surface, including small crevices. Compared with airbrushing as an example the hydroprinting process is much quicker and far more complex and detailed designs can be applied.