More than 35 million tons of plastic are generated in the United States each year with around 40 percent of that used in containers and packaging.
Much of that plastic needs some type of marking whether tracking numbers, identification data, or dial gauges. Laser marking on plastic is the most flexible way to add those marks as they are embedded into the material without directly contacting it. It creates a permanent mark that doesn’t wear on your tools or damage the surface.
Here’s a quick guide on what you need to know about laser marking on plastic parts.
How Laser Marking on Plastic Is Done
There are several challenges to marking plastics. While laser marking is a flexible method, not all plastics are the same. Their varying properties and additives can mean you need very individualized marking solutions for each kind of plastic.
Lasers can deal well with this challenge, particularly a short-pulse laser-marking machine like those from Lasitlaser.com. They give you better control of the heat input than with fiber laser marking on plastic.
You just have to tweak the laser wavelength and account for the type of plastic and specific additives in setting it. The additives are critical to getting high legibility and quality in your mark.
Types of Laser Marking for Plastic
You have at least three different options for how to do your markings when dealing with plastics.
While the laser breaks down or changes the structure of individual molecules, that difference isn’t always visible to the human eye. For that reason, color laser marking on plastic is a popular option for adding barcodes to packages. The color change happens through discoloration, bleaching, or carbonization, and the process is usually used on light-colored plastics.
Ablation involves removing a thin top layer to expose a contrasting base material below. This is the common method of creating automotive dials where the laser burns away a layer of paint on top of the plastic to make text and graphics.
Foaming or melting alters the surface of the plastic, melting it and trapping gas bubbles that appear during cooling. It creates slightly raised markings and is mostly used for black and dark-colored plastics.
With plastics, most laser marking is done for product traceability, secured ID cards, and car decoration.
Traceability marks could include a date of expiration or a barcode on the packaging. ID cards are usually a driver’s license, which uses a special layer of carbon-enriched plastic to print names and pictures. Using a grayscale laser along with the special plastic makes them hard to counterfeit.
Decorative but functional are the markings you find in car interiors or airplane cockpits. From the button controlling your window to the dash gauges, lasers remove a top layer of paint to expose the text and graphics with ablation.
Many other industries use laser markings on their plastic parts, including:
- Electronic components
- Circuit boards for cars
- Tools and tool handles
Add Your Mark
While there are challenges for laser marking on plastic, it can be the most flexible option for your packaging. The best laser marking machines can adjust based on the type of plastic to deliver crisp, legible markings and text. Special additives can improve the quality and visibility of your markings as well.
Check out our other articles here on our site to learn more about product packaging and special markings.