In the home appliance world, PMMA (polymethylmethacrylate, commonly known as plexiglass) is one of the most widely used materials for displays, user interfaces, and control panels in modern appliances. The need to customize these components with logos, functional directions, and information is critical not only for branding but also for the ease of use of the end product.
Historically, the industry has relied on traditional marking techniques such as pad printing and screen printing, which have several limitations:
- Need for cliches or masks for each different design
- Long setup time and production changeover
- Use of inks and solvents
- Difficulty in maintaining accuracy on complex geometries
- High consumable and maintenance costs
Today, laser marking represents a technologically advanced alternative that is revolutionizing manufacturing processes in the home appliance industry, particularly in the processing of PMMA.
UV technology for PMMA: precision and speed
PMMA, due to its high transparency, hardness and weathering resistance, is ideal for appliance control panels, but it also presents a challenge for marking. Its chemical composition requires specific approaches to achieve optimal results.
UV laser marking has proven particularly effective for this material. Unlike infrared lasers, ultraviolet light is better absorbed by PMMA, allowing photophysical and photochemical interaction that ensures high-quality markings without damaging the material.
Evolution toward high-power systems
Until recently, UV laser solutions for PMMA were limited to powers of 5W or at most 8W, as higher power systems were excessively expensive for many industrial applications. However, thanks to technological innovation and industrialization of manufacturing processes, UV laser systems of 10W, 20W and even 30W can now be accessed at significantly lower costs than in the past.
This recent introduction of high-power UV laser systems has been a turning point for the industry, offering several advantages over traditional low-power systems:
- Dramatically reduced processing times: a panel that used to take 30-40 seconds can now be marked in 10-15 seconds
- Ability to create markings with different finishes (from matte to glossy)
- More room to maneuver (increase % power) when needed
Practical case: Control panels for washing machines
A concrete example of the application of this technology is the marking of control panels for high-end washing machines. In this case, PMMA is used to create an elegant and functional user interface.
Before the introduction of high-power UV lasers, marking these panels presented several problems:
- Cycle times too long (up to 45 seconds per panel)
- Difficulty in maintaining uniformity across the surface
- Poor contrast of markings
- Complexity in managing different product variants
The implementation of a 30W UV laser system made it possible to:
- Reduce the cycle time to about 15 seconds per panel
- Achieve consistent quality across the entire surface
- Improve contrast and readability of markings
- Move quickly from one variant to another without setup time
Comparison with traditional techniques
UV laser marking of PMMA, especially with high-power systems, offers many advantages over traditional techniques:
| Appearance | Tampography | Screen printing | High-power UV laser |
|---|---|---|---|
| Setup times | 3-7 minutes | 5-10 minutes | A few seconds |
| Consumables | Inks, solvents, cliches | Inks, masks | None |
| Maintenance | Frequent | Frequent | Minimum |
| Accuracy | Media | Medium-high | Very high |
| Marking speed | Very fast | Quick | Medium-high with high-power systems |
| Versatility | Low | Low | Very high |
| Cost per piece | Low | Low | Very low for large lots |
| Initial investment | Medium | Medium | High |
| Environmental impact | High | High | Low |
The main advantage of laser marking is the absence of pre-setting time between batches. Whereas in pad printing or screen printing it takes several minutes to change plates or masks, with lasers it is possible to switch from one design to another in seconds, a key aspect in an industry where customization and product variations are increasingly in demand.
Innovation in the LASIT testing laboratory
To ensure optimal results in laser marking of PMMA, LASIT has implemented a state-of-the-art laboratory equipped with advanced instrumentation:
- 3D 4K microscope: enables detailed analysis of the marked surface, with precise measurements of the depth and morphology of the etching
- Spectrophotometer: allows you to determine the optimal wavelength for each type of PMMA and verify marking colors with scientific accuracy
- Climate chamber: for testing the durability of markings over time under different environmental conditions
- Abrasion tester: assesses wear resistance of markings
These tools enable the development of customized marking processes for each specific application, ensuring maximum quality and efficiency.
Advanced applications and future developments
The evolution of high-power UV laser technology is opening up new possibilities in the field of PMMA marking:
- Backlit markings: thanks to the precision of the laser, it is possible to create markings that, when backlit, distribute light evenly
- Multi-layer markings: ability to interact with different layers of the material
- Microtexturing: creating microscopic textures that add functionality to the surface
- Advanced gray scales: obtaining increasingly precise shades and gradations of gray
UV laser marking technology is evolving toward increasingly powerful and accurate systems that will further reduce processing time while maintaining or even improving the quality of the end result.
LASIT’s experience in the field
LASIT has developed specific solutions for laser marking of PMMA in the home appliance industry, working with the world’s leading manufacturers. The company has provided complete integrated systems that include:
- UV lasers of varying powers (3W, 5W, 8W, 10W, 20W, 30W)
- Vision systems for self-centering
- Customized software for integration with production systems
- Marking stations with rotary table to increase productivity
LASIT’s approach is based on customizing the solution to the customer’s specific needs, with a focus on optimizing the production process.
High-power UV laser marking today represents the most technologically advanced solution for PMMA customization in the home appliance industry. Despite the higher initial investment compared to traditional techniques, the advantages in terms of flexibility, speed of production changeover, quality of the result, and reduced operating costs make this technology particularly attractive to home appliance manufacturers.
With the introduction of increasingly powerful and precise lasers, LASIT continues to push the boundaries of this technology, offering solutions that enable appliance manufacturers to improve the quality of their products and optimize production processes.