The recent turnkey laser labeller, Label Marker E from Rofin, partner of Laser Resources , is designed with the high uptime needs of automotive assembly lines in mind, but the labellers are finding applications in several other manufacturing environments.
The key advantages of the special laser etched labels are their ability to withstand high temperatures, weathering and solvents and their tamper-evident characteristics.
The labels can withstand under-bonnet (hood) solvents and temperatures and so are increasingly used to label a range of assemblies, including the engine block.
Many people will have noticed the grey or black labels on the inside of their car petrol filler opening and car door frames - these are normally permanent as they are laser marked onto such label stock.
Information such as VIN data, fuel type and car tyre pressures are entrusted to such permanent, non-transferable labels for the lifetime of the car.
In electronic production lines, tiny barcodes are also laser marked on the label material and stuck to printed circuit boards for auto tracking through production lines; unlike conventional labels, these easily withstand wave solder or IR solder machine temperatures.
But it is the security aspects of this special material that attract many of the new applications: once stuck onto a surface, the label cures into a near-permanent addition. The only way to remove it is by destroying the label; scraping it off into tiny fragments.
For this reason one can be certain that labels cannot be removed from one item (one still under warranty, for example) and then attached to another (maybe out of warranty and dysfunctional).
Small stickers are similarly used to cover screw heads that must be opened for access, acting as a secure way of voiding warranty on items that has been tampered with.
These labels are generally designed with multilayer and the laser is used to vapourise the top (often black) layer, revealing the lower (often white) layer.
The Rofin laser marker can mark characters onto these labels at a rate of up to 1000 characters per second, so label production can be incredibly quick.
There is another valuable feature of using industrial lasers to laser mark labels: the system can also laser cut the labels - into whatever shape required.
The new system design is an evolution from the D-line version already in-use at many car manufacturers around the world. It is more compact and is based around Rofin's end-pumped 30W E-line solid state laser.
Automated operation comprises reel-to-reel feed; sensors to detect misfeeds, end-of-reel, splices; pneumatic knife shearing and of course laser marking and cutting of labels.