UV Laser Marking of TiO2-Filled Polymers Without Cratering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods struggle to efficiently and effectively mark polymer materials containing opacification materials like titanium dioxide with clarity and speed, without damaging the material, especially for large field marking and high-speed packaging applications.
Innovation Solution
A high-speed ultraviolet (UV) laser system with a diode pumped solid state pulsed laser, operating at 355±0.1 nm with an average output power of 4 to 55 W, and a minimum scan speed of 3 meters/second and pulse frequency of 30 KHz, is used to create permanent marks without ablation, enabling fast and precise marking of multiple lines, including 2D barcodes, on polymer materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If conventional laser marking methods are used on polymer materials containing opacification material, then marking can be achieved, but the material is damaged with excessive cratering and ablation
Solution Approach 1:
The patent applies parameter changes by using a specific ultraviolet wavelength (355±0.1 nm) that optimally interacts with the opacification material without excessive energy transfer to the polymer substrate. The pulsed laser regime with controlled duration and frequency, combined with high scan speed (minimum 3 meters/second), modifies the energy delivery parameters to achieve marking with minimal cratering (less than 10 microns).
Solution Approach 2:
The patent employs periodic action through pulsed laser operation at a minimum frequency of 30 KHz. This periodic energy delivery allows the material to dissipate heat between pulses, preventing cumulative thermal damage while maintaining marking effectiveness. The pulsed regime combined with high scan speed creates a non-contact, cold marking process that avoids melting and excessive ablation.
2Productivity
If high-speed scanning is used to mark multiple package labels, then productivity increases, but marking precision and material integrity may be compromised
Solution Approach 1:
The patent maintains continuity of useful action by operating the laser at high scan speeds (minimum 3 meters/second) with continuous pulsed operation at 30 KHz or higher frequency. This continuous high-speed marking process eliminates idle time between marks and maintains consistent marking quality across multiple package labels, achieving both high productivity and precision through sustained optimal operating conditions.
3Productivity
If high power laser is used to mark materials quickly, then productivity increases, but material damage increases
Solution Approach 1:
The patent uses periodic pulsed laser operation where high power is delivered in short bursts at minimum 30 KHz frequency rather than continuous high power. This periodic delivery with high scan speed (minimum 3 meters/second) allows the material to recover between pulses, achieving high marking rates without excessive cratering (less than 10 microns) by controlling the duty cycle and pulse duration.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The UV laser system achieves high-quality, permanent marking on polymer materials with minimal cratering, maintaining material integrity, and supports high-speed packaging by producing marks that meet ISO and GS1 standards for clarity and durability, even on materials like DUPONT TYVEK 2FS, without compromising the substrate.
Implementation Method 1
The ultraviolet (UV) wavelength of 355 nm is commonly utilized because it is well absorbed by many polymers and can induce a color change in the polymer without significant heating
Implementation Method 2
oxidation of the polymer chain by oxygen in the air, which can occur after the initial photolysis event
Implementation Method 3
removal of the opacification material, such as titanium dioxide
Implementation Method 4
permanent marks without ablation of other markings
Data Source
AI summary
Systems and methods of permanently marking a material containing an opacification material may include marking the material with a laser system. The laser system may be an ultraviolet system, and the laser may be a solid state diode pumped and pulsed 4 watt to 55 watt unit with a minimum scan speed of 3 meters/second and a minimum frequency of 30 KHz.