Evoclear Welding – The Clear Medical Solution
Our product partners, EVOSYS, now offer a 2µm alternative to the original 1µm laser plastic welding process.
For medical applications, this represents a real breakthrough in that two clear plastic parts can now be joined together without an additional absorber.
Using EvoClear’s 2µm transparent laser plastic welding process, joints are particulate-free and avoid any risk of contamination.
With no possibility of colour changes, it meets the needs of microfluidics, diagnostic cassettes and assays that require components to be transmissive in either the visible or UV spectra for analysis.
The 'one micron' problem
Bonding clear parts is a major problem for medical device manufacturers that need the precision advantages of laser plastic welding combined with fully clear assemblies. In the original “one micron” laser plastic welding (through-transmission laser welding) process, 95% of the laser radiation introduced to an optically clear plastic will transmit through the plastic.
As a result, there is insufficient light energy left over to transform to the thermal energy needed to create a melt or bond.
To create more thermal energy, the base component requires a laser absorbing additive such as carbon black or a special laser absorbing additive so that the light energy turns to heat and fuses both the upper (transmissive) and lower (absorbing) layers.
With these absorbers, it is possible technically for 1µm laser welding to weld clear plastics. However, using them can be expensive, difficult to apply and create concerns regarding biocompatibility as well as slight colour changes.
Clearly superior
In the EvoClear process, instead of welding in the usual wavelength range of 800-1100 nm, 1500 -2200 nm (1.5 – 2µm) is used.
Applied to naturally coloured or clear thermoplastics, significantly less (70-85%) of the light energy is transmitted with EvoClear welding while the remaining (15-30%) is absorbed, creating volumetric heating and melt throughout the joint interface without additive.
A finished fully clear assembly is the end result whilst still offering the same advantages of “one micron” welding such as ultra-fine weld seams, repeatability and various joint styles such as lap joints, curved parts or radial joints for tubing or catheters, etc..
A reduction in material costs, perfect clarity, a decrease in production steps and complexity in production lines – the advantages are clear.
For further information on the EVOSYS EvoClear process, please contact sales@tlm-laser.com