Offering the most advanced pad printing processes for plastic parts
Often people will want more than one color on their part. This is where pad printing can help. In addition to choosing part surface color finish, color and gloss can be added to the parts to create the desired appearance.
Plastic is a composite material made from various synthetic and semi-synthetic organic compounds. Popular plastics which can be used in injection molding processes include acetal, nylon, ABS, PVC, polycarbonate, and polypropylene. We know plastics. And we know injection molding. For over a decade, we’ve developed processes that meet the needs of our customers while controlling costs and turning out robust parts with finishes that last.
Finishing of plastic parts can be done for protection, decoration, and to achieve other desired appearance changes. A plastic part can be nickel-plated to protect it from oxidizing. The surface of parts can be mechanically brushed in just about any pattern, to create a textured look.
Finishing choices are many, and our team can help you determine the best injection molding secondary processes to achieve your desired result. Pad printing is just one of the processes we can use.
First-rate pad printing requires experience and knowledge
Pad printing can be an excellent choice for plastic injection molded parts when the desired appearance of the end-product requires more than one color. The pad printing process is fast, inexpensive, and can be designed to conform to curves and rounded edges more easily than other paint processes like screen printing.
Also referred to as stamping, pad printing is a very simple, quick and affordable painting process for adding color to plastic injection molded parts. In basic terms, to create a pad printing process, a large pad is created, incorporating a raised design that will pick up the paint, then apply it to the plastic. The best drying or curing method chosen following pad printing is determined by the many variables in material and the molding process selected.
Color matching, patterns, logos and other specifics, and other injection molding secondary process may be needed.
Pad printing can be a good option when intricate details and logo accuracy are needed. At ICOMold we’ve refined our pad printing injection molding parts process to be efficient and cost-effective while consistently producing an excellent bond and a durable finish.
This method of applying paint to plastic parts allows for some creativity and color options while keeping expense at a minimum.
The pad painting process is just one injection molding secondary process we offer
Following the molding process, we can offer many different effective paint and finish options for many kinds of plastic parts. In some cases, pad printing can bring the most desirable appearance within budget, while providing a long-lasting finish.
For more details and painting process options for your injection molding parts, see our list of other Injection molding painting processes.
Our design experts are available to help you and your team evaluate all the options and make the best choice for achieving the results you need with a quality bond you can be proud of.
Preparing injection molded parts for pad printing
Proper surface preparation is crucial for a successful adhesion to occur. For powder coating, liquid paint, pad printing or whatever methods are used, surface preparation is central.
There are plenty of chemical and mold process factors that must be considered before choosing and designing plastic injection molded parts finishing methods. A good bond can be achieved by understanding these factors – and taking care to properly prepare the surface of the plastic parts.
Another concern when it comes to pad printing is the potential for contamination in the injection molding process. We’ve developed methods for overcoming the challenges that can come with deburring and overspray, as well as other possible elements of the injection molding processes. At ICOMold we’re experts in mold building and plastics manufacturing, and in developing successful injection molding secondary processes.
Many plastics used in injection molding generate electrostatic surface charges. The electrostatic charges tend to attract contamination, almost magnetically. We avoid painting defects and maximize adhesion by knowing plastics so thoroughly. And we never stop analyzing the entire process, from mold design, to material options, to mold prep and part surface preparation.
- We strive to develop tooling designs modified to downstream painting requirements in the plastic parts that will be molded
- Designing for as few cutouts as possible helps provide a better painting process
- Rounded part edges can be more easily covered with paint than sharp ones
- Because residual burrs can lead to contamination all the way into the painting booth, we keep deburring to a minimum
- We also have developed systems for keeping tools extremely clean, to avoid excessive buildup of the materials used in the injection molding process
Other ways we optimize part cleaning for pad printing
Through the use of release agents, additives, filler materials and fibers we can improve the characteristics of plastic injection molded parts and the bond we can create with various paints.
We’ve developed proven processes and procedures for keeping these agents off the plastic part surfaces, to protect from transfer to the plastic parts we mold.
Get instant access to ICOMold’s library of plastic injection molding articles by signing up for our newsletter
Pad printing on plastic requires surface energy
The types of plastics used in injection molding processes don’t carry much surface energy. This can make adhesion of paints and other finishes difficult to ensure. Even cleaning and some pretreatments can go a long way toward creating a good surface for pad printing and other paint processes. We often pretreat plastics that are going to be painted. This allows us to increase the surface energy of the part surface and improve the quality of the paint adhesion.
CO2 snow-jet, plasma and steam cleaning are just some of methods we use to create stronger bonding. These processes can be designed to reduce costs and decrease the amount of space needed. The parts cleaning and prep process can sometimes be included in the painting line system.
The electrostatic charging of some plastic surfaces can be counteracted by ionization. To prepare for a good connection between part and paint in some non-polar plastics, like polypropylene (PP) and polyethylene (PE), we sometimes recommend activation of the part surfaces through ionization before painting.
Ionization processes include:
- Gas phase fluorination
- Atmospheric pressure plasma activation
- Corona treatment and flaming
Color matching methods for pad printing processes
Colorants can be added to help develop the perfect colors for your parts. We can also adjust gloss or provide more than one precise color for your design. We can utilize:
- Pantone color matching
- Physical sample color matching
- RAL color matching
Surface etching for a better pad screen printing process
Most plastic parts are smooth when they emerge from the molds. When a strong finish adhesion is needed, the surface of the part can be etched to prepare for painting. To do this, we use a chemical agent to create some roughness that can’t be seen, and gripping areas that will provide a better bond for the paint. Etching must be done carefully and correctly, to avoid parts damage.
Other surface etching methods we employ:
- Chemical reaction, including flame-induced oxidation
- Plasma conditioning
- Light-sensitive chemicals, called photosensitizers, followed by exposure to ultraviolet light
- Ozone-generating electrical corona discharge
A simple process for adding color to end-products
Injection molded plastic part surface preparation is vital to any successful painting process. If the bond isn’t good and long-lasting, the design won’t matter. A strong bond is the key to long lasting finishes. At ICOMold, we offer options that will bring you the best possible end-result and products you can offer with confidence.
Injection Molding Production Highlights
> Instant mold and part quote
> Low cost, quick build and quality production
> ICOMold's Lifetime Warranty on Production Molds
> Online project management
> Trouble-free part modifications
> No size limitations
> Any commercially available material and surface finish
What is the process for injection molding production?
ICOMold’s instant online plastic injection molding quote and mold frame sharing technology enables us to simplify and shorten both the quoting and tooling manufacturing process for custom plastic injection molding.
- Load your 3D CAD file to get an instant mold and part quote
- Upon order confirmation, ICOMold starts the mold and part order process
- Tooling design review by ICOMold engineers
- Upon design approval, ICOMold begins building your injection mold
- Customer examines samples for approval
- Part production begins
Go to our plastic injection molding and CNC machining case studies page to see how we helped customers on their projects.