Water Transfer Printing Technology
Youíve heard it by many names: hydrographic printing, 3D printing,
fluid imaging, immersion printing, or simply water transfer printing. Whatever
the name, the processes are the same. Using the water transfer printing process,
you can transfer high-definition 4-color graphic patterns to many complex
three-dimensional shapes. In most cases, you can transfer the filmís inks to
steel, aluminum, plastic, wood, and many other substrates. Common patterns are
wood grain, carbon fiber, and camouflage. For years, the automotive industry has
embraced this technology and process to apply decorative trim throughout vehicle
interiors. Early on, the sporting goods industry found that water transfer
printing was ideal to apply camouflage patterns to gun stocks and bows.
Today, applications are showing up in many new categories of manufacturing
including medical, marine, computer, and general industrial. Some of the more
common questions that arise regarding the transfer printing process are
Are there licensing fees involved with water transfer printing?
Dating back to issuance of the original process patents, anyone wanting
to enter the water transfer processing arena had to pay substantial fees to
licensee the technology. Even then, the licenses granted were very restrictive
and limiting. This is not the case anymore. The technology finally is available
on the free market and available to anyone, with no licensing fees or
How does the water transfer printing process work?
Water transfer printing starts with pre-printed high-definition
patterns on a water-soluble transfer film. From there, several important steps
must be followed to develop a successful print:
Step 1: Preparation. Depending on the substrate, some or all of the following
steps may be necessary: chemical pretreatment, fill and sanding, masking,
application of spray chemical adhesion promoters, plasma treatment, or corona
Step 2: Tooling and Fixtures. Parts are attached to a specific fixture, which
holds the parts during the dip process. Generic fixtures can host many different
parts but occasionally, engineers have to design custom fixtures to host unique
Step 3: Primer Painting. A coat of primer paint is applied to the part. This
paint serves as a bonding agent between the part and the transferred inks. The
paint color typically becomes part of the background contrast color as well.
Step 4: Ink Transfer or Dipping. The fixtured part is now dipped through the
inks, which are floated on water in a specialized processing tank. As the parts
are immersed through the inks into the water, displacement of the water carries
the inks around the three-dimensional shape of the part.
Step 5: Wash and Rinse Process. Parts travel through a conveyorized hot water
wash line to remove excess processing chemicals. The last stage of the wash line
dries the part.
Step 6: QC Inspection. A detailed inspection of the ink transfer and adhesion
is completed. On occasion, parts with extremely complex geometry may require
manual touch-up using the transfer inks.
Step 7: Sealing Top Coat. Based on the customerís specifications, either a
high gloss, satin, or flat top coat of clear Urethane finish is applied to seal
the inks. One or more coats may be applied and in some cases, buffing and
polishing is required between coats.
Step 8: Final QC and Packing. A thorough inspection is conducted by a trained
professional. Once complete, the parts then are packed according to the
customerís specifications and prepared for shipment or final assembly.
How do I get started with water transfer printing?
Several companies exist that can guide you through the processing
options. Companies offering water transfer films should offer hundreds of stock
or custom patterns and can supply you with the technology, equipment, supplies,
and training to decorate components in your facility. Make sure that proper
training is included with any decision to purchase water transfer printing
equipment. This is very important to develop a consistent and reliable system.
If in-house processing is not your preference, there are many Ďmaster
decoratorsí located throughout the U.S. and around the world that offer this
custom decorating process.
Plastics Decorating would like to thank Mike Richards, business
development manager for TWN Industries, Inc., for his assistance with this "Ask
the Expert" article. For more information, call (913) 449-4879 or e-mail