Laser marking refers to the process by which permanent markings are made on a given surface. No surface is removed during the process but rather, only alterations are done to give out a different appearance. Laser marking has had a wide range of applications in the industry. As such, it is also used on various types of materials, including plastic. Here is a guide on plastic laser marking.
What Kinds of Plastics Can be processed by Lasers?
There are many materials out there that are compatible with laser marking. They include glass, metals, and ceramics among others. We also have plastics which have gained a lot of traction when it comes to laser marking applications. However, there are different types of plastics that are normally used for laser marking. Each one of these exhibits different properties, both physically and chemically. It is important to have this in mind as it implies that the marking process will be different for each.
Typically, plastics can fall into one of two broad categories, that is, thermosets and thermoplastics. Thermosets are known for their ability to hand relatively higher temperatures. This means that they do not lose their structural form when exposed to additional heat. Instead, they can give out some charring and discoloration. This favors the marking process as it brings in some contrast. Examples are polyimide, Bakelite, and rubber-based ones among others.
Thermoplastics on the other hand are more sensitive to heat. Here, heat normally results in melting. This property is leveraged during laser marking through the creation of shallow marks. They are however not suitable for high contrast marks. Examples are Nylon, PVC, ABS, and all those that fall in the Poly family.
What are the Different Lasers for Marking Plastics?
The type of laser is a critical part of the laser marking process. By understanding the way different types of lasers work, you will be able to choose one that is best suitable for the material at hand. The commonly used lasers for marking plastics are:
This one uses a tube that has been filled with gas where electricity is passed through. This results in the production of monochromatic light. CO2 lasers are suitable for marking various kinds of plastics. They also provide a fast marking speed. They are also easy to control and are usually a more affordable option than the rest.
A green laser is a top option for marking most elite materials. It maintains just the right wavelength to deal with the materials. Another big advantage that comes with the green laser is the fact that it does not generate any heat. It, therefore, works well with very sensitive materials as it has a lower chance of damaging them. It also offers great precision thanks to its relatively tiny spot diameter. All these make it a perfect candidate for plastic laser marking.
The UV laser is a great option when it comes to high-marking precision jobs. This is because they have a very tiny spot seize. They also have a wide power range which can be adjusted to suit soft products. This makes them a good option for plastics.