Black on Plastic
Creating permanent marks on plastics can be a challenging process: printing methods are susceptible to removal using solvents and direct laser marks typically “burn” the surface creating a contrast rather than a true black mark. Some plastics even have to be molded with an expensive additive to facilitate a direct mark. In some situations, TherMark products can offer a cost-effective alternative marking method which can produce black marks on a range of thermo-plastics. Some common applications are below.
- Molded components
- Battery housings
- Cattle tags
- Containers
- Tubes
|
|
The process works in a similar way to regular laser bonding, however, due to the lower melting points of plastics, the pigment in the material is typically embedded just below the surface of the plastic rather than on top. The mark will be visible but also protected from damage and removal, giving the required permanence.
Compatible Substrates
Due to the extremely wide variety in plastic materials, marking plastic with TherMark laser marking materials can be a hit or miss proposition. We have not tested on an exhaustive list of plastics, but, as a general rule, we have better success on thermo-plastics than on thermo-sets. Below are some plastics on which we have had success.
Nylon |
HDPE |
UHMWPE |
Polycarbonate |
PVC* |
|
Because of the wide variety of plastics available and the importance of using the correct process settings, we highly recommend talking to a TherMark representative before purchasing materials or trying to mark your product. Also, for plastics not listed, please contact us to discuss if marking will be possible.
Product Recommendations
LMC12 |
Originally formulated for marking glass and ceramics, LMC12 is now used more often for marking black on thermo-plastics. It comes as a liquid product that can either be foam brushed or sprayed through an airbrush. Airbrush is preferable as it generates a homogeneous coating over the substrate. These application methods make it more suited for manual or batch processing. |
LMP500 |
A pad-printing ink, LMP500 was designed to be appropriate for higher volume batch and inline assembly jobs. It will require the use of a pad-printing machine and some level of process integration. |
*Marking PVC can cause the release of chlorine gas which can be harmful to the laser operator and corrode the laser head. It is important to use adequate fume extraction and air filtration when attempting to mark PVC with a laser.
|