The Problem of Marking on Clear Plastics Solved: From Parameters to the Complete Solution

Transparent plastics often present problems with unclear markings and damage to the material.They offer a complete solution from laser parameter adjustment, to process selection, to actual operating skills, which helps to solve problems such as blurred or white marks and improves marking efficiency and product quality.

Why is it that marking on transparent plastic is never very good?

Many friends have given me feedback that when they try to mark plastic, the characters are blurred, or they accidentally burn a crack into the plastic.This is mostly because of the special properties of the materials. Transparent plastics have a low absorption rate for laser light and heat easily spreads out. If the parameters aren't set correctly, the machine can be damaged.Don't worry, we'll take it step by step.

What are the key parameters?

The more power the better?

Many people think that if they turn up the power to the maximum they will be able to cut deeper, but in fact they just end up burning the material.He suggests beginning with a low power setting (such as 30 % of the power of a 20-watt fiber laser), and a high frequency (over 20 KHz), so that the mark will be clear, but there will be no excessive burning.

The golden combination of speed and focal length.

If the speed is too fast, the marking will be white; if it is too slow, it will burn through.It is recommended that the speed be set at 800-1200 mm / s, and the focus adjusted to 0.5 mm below the surface of the material.Different brands of plastic may require slight adjustments, so remember to keep track of the data.

Small improvements in craftsmanship.

Pre-treatment improves adhesion.

After cleaning the surface with alcohol, apply a thin layer of special marking paint (don't use ordinary paint!). This will make the mark darker and more permanent.I found a product online that cost only a few dollars a bottle, and it worked.

Cooling devices can't be done without.

When working continuously, it is essential to turn on the air cooling, and adjust the air pressure to 0.2-0.3MPa. This not only cools the workpiece and prevents deformation, but also blows away the debris produced by the marking process.If you've ever had the problem of the edges of your paper being frayed, there's a good chance it's because the nozzle isn't pointing straight.

A guide to avoiding pitfalls.

Last week, a client was printing a logo on acrylic, but there was always a halo around the edge.Later, I discovered that the lens of the laser head was dirty and cleaned it, and the problem was solved.There is one small detail: the focus needs to be readjusted for materials of different thicknesses. Don't be lazy and use the same set of parameters for all!

If the mark is yellow, try reducing the pulse width (for example, from 100ns to 50ns) and lowering the number of repetitions.If you really can't get it to work, try changing to a green laser--it's more expensive, but it's definitely more reliable when it comes to transparent materials.

Common questions and answers.

Q: What can be done about fogging of the surface after labeling?

A: By reducing power by 10 % and increasing the spacing from 0.05 mm to 0.1 mm.

Q: How long does the mark last?

A: Change the coating to aluminum oxide and control the humidity to under 40 %.

Q: Why is it that small characters can't be carved out completely?

A: Change the fill mode to bidirectional scan, and don't make the character height less than 3 mm.

Remember to do a gradient test every time you change the material.The company can test different parameter combinations on the scraps, and then use the most effective combination for the batch. This saves on the cost of scrap.