HYDROGRAPHICS

M.Nagarjuna

11071A2425

What is Hydrographics?

• Hydrographics also known as Water transfer printing , 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.

• 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.

Water transfer printing | The Process

• The whole process takes place in 6 stages.

• Stage 1: Film printing

• Stage 2: Primer & Base coating

• Stage 3: Activation

• Stage 4: Ink transfer

• Stage 5: Washing process

• Stage 6: Clear coating

Stage 1 : Film printing

• The first step is to prepare a film

of the print , which will later be used

to transfer the design on the surface.

• The film developed contains the

pattern or design according to the

requirement.

• A film printer is used for this

purpose.

• The polyvinyl alcohol film produced

is water soluble.

Stage 2 : Primer & Base coating

• The surface to be painted is coated with a layer of primer initially.

• A primer or undercoat is a preparatory coating put on materials before painting. Priming ensures better adhesion of paint to the surface, increases paint durability, and provides additional protection for the material being painted.

• After the primer dries up layers of base coating is done on the surface.

• Base coat determines the color of the surface after the process is finished.

Stage 3 : Activation• The film is spread evenly on the water using an automatic

unrolling unit.

• An activator chemical is sprayed on the film to dissolve it into a liquid and activate a bonding agent.

• The film once dissolved leaves a liquefied floating pattern on the surface.

• Care should be taken while spreading the film on the water surface.

• The activator chemical should be sprayed evenly throughout the surface of the film.

Stage 4 : Ink Transfer

• The next step is to transfer the print from the water to the

surface.

• For this , the parts are dipped are dipped into the water either manually or by an automatic dipping arm.

• The print layer along with the polyvinyl alcohol backing then wraps around and adheres to the part.

• 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.

• One of the most common causes of a failure to achieve adhesion between the two layers is a poorly applied activator. This can be either too much activator being applied or too little

Stage 5 : Washing Process

• This step involves washing the dipped parts using the

automatic washing machine.

• The machine washes the printed surface at a preheated temperature , thus impressing the pattern further.

Stage 6 : Clear coating

• In the final process step, the decorated product is

covered with an automotive-grade urethane. This gives the object a glossy or matte shine, depending on preference.

• The urethane also acts as a protector from harmful UV rays and chemicals that may ruin the pattern.

• When the final coat has dried, the object is sanded and polished to shin

This is how the finished parts look