Hydrographics, also known as immersion printing, water transfer printing, hydro dip, hydrodip, hydrodipping or cubic printing, is a method of applying printed designs to three-dimensional surfaces. The hydrographic process can be used on plastic, metal, hardwood, glass, and various other materials.
The water transfer printing process is extensively used to decorate items that range from weapons, bike parts, entire all-terrain vehicles and car dashboards, and small items like bike helmets or other automotive trim. Films can be applied to all types of materials 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 the item and adheres to it. 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 the product. One of the most common causes of a failure to achieve adhesion between the two layers is a poorly applied activator. This is the fault of too much activator being applied or too little.