Which plastic laser marking machine
Laser marking on plastic starts with one question: what is the polymer, and what colour is it? That decides the wavelength, and everything else follows.
HeatSign · UV, CO2 and fiber
Plastic laser marking machines
Not every plastic marks the same way. ABS and PC go dark on their own. PP and PE often need an additive mixed into the resin. Clear plastic needs a different laser. Tell HeatSign your polymer and we will tell you which machine to buy.
ABS, PC, PVC, PET, PP, PE, nylon, acrylic and most engineering plastics.
One polymer name is enough to start. A HeatSign engineer replies within one business day.
Cold marking · 355 nm
HS-UV Series
UV laser marking machine for plastic
Pick this when the part is thin, white, medical, or melts easily. Marks PE, PP and white ABS with no heat damage.
The one clear plastic absorbs
HS-CL Series
CO2 laser marking machine
The only laser that clear acrylic and PET will take. Also fast and cheap to run on film and cartons. It cannot mark bare metal.
Two wavelengths, no cable
HS-FL10B
Handheld laser marking machine
A plastic laser marking machine you carry to the part. Blue light for plastic, infrared for metal, 2.7 kg, no cable.
View this machine
Marks on a moving line
HS-LY Series
Flying laser marking machine
Marks dates, batch codes and serials while the conveyor keeps moving. No ink, no solvent, nothing to refill.
View this machine
Between two of them?
Tell us your plastic material, the colour and how many parts you need mark per hour. A HeatSign engineer will help you choose the right machine. Contact Us Now!
What HeatSign marks on plastic parts
Six things go on plastic parts. Most customers need two or three of them.
Content | What it is for |
|---|---|
Serial number | One number per part, for warranty and returns |
Batch and date code | Links the part to a shift and a mould |
DataMatrix or QR code | Holds everything in one square. Scanned at assembly |
Brand and logo | Replaces a sticker that peels off |
Compliance marks | UDI, CE, recycling code, material code |
Cavity number | Shows which mould cavity the part came from |
Where you see plastic laser marking
These are the common industries, not the full list.
Medical Devices
Syringes, catheters and housings. UDI codes that survive the autoclave.
Will your plastic mark?
The polymer decides this, not the machine. Find yours before you compare plastic marking machine prices.
Some plastics go dark on their own. Some only make pale bubbles. Some do almost nothing until a laser additive is mixed into the resin.
Polymer | What the laser does | Result | Needs an additive |
|---|---|---|---|
ABS | Turns dark | Sharp and dark | No |
Polycarbonate (PC) | Turns dark | Sharp and dark | No |
PVC | Turns dark | Dark. Needs a fume extractor | No |
PET and PETG | Turns dark | Dark | No |
Polystyrene (PS) | Turns dark | Dark | No |
PPS, PPO, LCP | Turns dark | Dark. Common in electronics | No |
Polypropylene (PP) | Makes bubbles | Pale and faint | Usually |
Polyethylene (PE, HDPE) | Almost nothing | Hard to read | Yes |
Nylon (PA6, PA66) | Depends on the filler | Changes a lot | Often |
POM acetal | Almost nothing | Poor | Yes |
Acrylic (PMMA) | Needs CO2 | Frosted white | No |
Silicone and TPE | Depends on the grade | Changes a lot | Test first |
Colour and filler matter as much as the polymer. Black ABS and white ABS behave differently. Glass-filled nylon behaves differently again. Not sure about your grade? Ask HeatSign and we will confirm before you order.
Four things that go wrong with plastic marking
These four cause almost every complaint we hear. Each one has a simple answer, and none of them needs a more expensive plastic laser marking machine.
01 Your plastic barely marks at all
PP, PE, nylon and POM let the beam pass straight through. Turn the power up and the surface melts before it goes dark.
Add a laser additive to the resin. A small amount makes the plastic absorb the beam, and then it marks cleanly. Sort this out with your resin supplier first, because it decides which HeatSign machine you need.
02 The edges melt or turn yellow
Thin walls, white parts and medical plastic show heat damage first. The middle looks fine and the edge is burnt. White plastic goes yellow all over.
Use a UV laser instead. It marks the surface without heating the plastic underneath, so nothing melts and nothing yellows. This is why medical and thin-wall parts are UV marked.
03 The beam goes straight through clear plastic
Aim a UV or fiber laser at clear acrylic or a PET bottle and the light passes through. Nothing happens on the surface, and more power does not help.
Use a CO2 laser. Clear plastic absorbs that wavelength and turns frosted white where the beam lands. For clear parts this is the only laser that works.
04 You need a light mark on a dark part
Making plastic darker does not help on black ABS. You end up with black on black, and nobody can read it.
Turn the power down and make bubbles. Less energy leaves tiny bubbles just under the surface, and they look pale grey against the black. Same machine, different settings, and HeatSign sets it on your part.
Laser marking, laser etching or engraving plastic?
Buyers use these three words for the same thing. They are different, and the difference decides what you buy.
Process | Depth | What you get | Use it for |
|---|---|---|---|
Marking | Surface only | The colour changes. Smooth to touch | Codes, logos, dates. Most parts |
Etching | 0.025 – 0.13 mm | A shallow groove you can feel | Grip areas and texture |
Engraving | 0.25 – 1.9 mm | A deep cut | Parts that wear, and moulds |
Most plastic parts need marking, not etching. It is fastest, it takes almost nothing off, and it does not weaken a thin wall. Tell HeatSign which one your drawing calls for, and ask for etching or engraving only when someone has to feel the mark.
Laser marking plastic parts, the questions we get most
Can you laser mark polypropylene?
Only weakly, unless the resin has a laser additive in it. PP makes pale bubbles instead of going dark, so the contrast is low. On white PP it is often unreadable.
If you control the resin, ask your supplier for a laser-markable grade. If you do not, HeatSign will show you the best result we can get on your material as it is.
How much additive does the plastic need?
Less than most people expect. Suppliers quote 0.01 to 4 percent by weight in the finished part, and most grades sit under 1 percent. At that level the part looks and moulds the same.
Two things push it higher: flame retardants and glass fibre. Both absorb some of the energy, so the loading goes up.
We make medical parts. Can we use an additive?
Yes, but the additive has to be a qualified one. It must be non-migratory and biocompatible, tested to ISO 10993 and USP Class VI, and it must not fade after sterilisation.
Your resin supplier holds that data, not the machine supplier. Ask them for it early. Once you have a qualified grade, HeatSign sets the machine to it.
Will the code pass a UDI or GS1 grade check?
Codes are graded A to F on contrast, cell position and shape. You do not control which scanner the hospital or the warehouse uses, so aim for the highest grade you can get, not the minimum.
Contrast is what usually fails, and contrast comes from the polymer as much as the laser. Tell us the grade you need and we will confirm it is reachable before you order.
Why does the mark change between resin batches?
Because the resin changed. Laser marking is sensitive to pigment, filler and additive levels, and those drift between lots. A batch that marks beautifully in March can go pale in June.
The fix is on the resin side. Buy from a supplier with tight lot-to-lot control, and write the laser-markable grade on the purchase order, not just the polymer name.
Is it safe to mark PVC?
Yes, if you use a fume extractor. PVC makes chlorine gas when it gets hot. The extractor pulls that gas away, and every plastic marking machine should have one anyway.
Cutting PVC is not safe. Cutting makes far more gas than marking. HeatSign does not recommend it.
Should we buy a machine or send parts out to a marking service?
Pay someone else if: you only have one batch, or you are still testing.
Buy a machine if: you will mark parts every month. You pay once, and after that each part costs almost nothing. Your parts also stay in your factory.
Tell us how many parts you mark in a year. We will work out both costs for you.