Thomas Kolbusch | Coatema Coating Machinery GmbH: How does heat and mass transfer fundamentally limit the speed of drying processes?

Why settle for inkjet's viscosity limitations when Laser-Induced Forward Transfer can print high-viscosity materials with zero contact?

Laser-Induced Forward Transfer (LIFT) represents a major shift in digital printing of advanced functional materials. Unlike traditional inkjet printing, which struggles with high-viscosity inks and larger functional particles, LIFT utilizes a laser beam to precisely transfer material from a carrier donor belt to a target substrate. The laser energy vaporizes or melts the ink locally, propelling it across a micro-gap with high accuracy without any physical contact with the substrate.

The core of this implementation is a continuous, recirculating seamless donor belt. A conventional printing process continuously coats the donor belt with a uniform film of functional ink, and as the belt rotates, a high-frequency pulsed laser selectively transfers the patterns. This closed-loop configuration ensures that unused ink and solvent are continuously recycled, maintaining consistent viscosity and rheological properties over long production runs.

Operating at resolutions up to 600 DPI, this digital technology eliminates the "cappuccino effect" and nozzle clogging issues common in inkjet systems. By avoiding physical screens or masks, manufacturers gain absolute design flexibility, allowing them to rapidly transition between patterns for printed electronics, fuel cells, and batteries without hardware modifications.

In this short video, you can learn:
* How Laser-Induced Forward Transfer (LIFT) operates as a non-contact, mask-free digital printing method.
* The mechanics of the continuous recirculating donor belt system that maintains stable ink rheology and eliminates material waste.
* Why LIFT overcomes the viscosity and particle-size bottlenecks that restrict conventional inkjet and screen printing.

📋 **Clip Abstract** This clip introduces the mechanics of Laser-Induced Forward Transfer (LIFT) technology developed for high-viscosity and large-particle printing. It explains how a continuous recirculating donor belt combined with selective laser propulsion achieves a non-contact, 600 DPI digital printing process suitable for printed electronics and battery manufacturing.

Can Laser-Induced Forward Transfer (LIFT) bridge the gap between low-viscosity inkjet printing and high-throughput roll-to-roll manufacturing?

While conventional inkjet systems struggle with nozzle clogging and strict rheological constraints, LIFT technology accommodates exceptionally high-viscosity regimes. By utilizing a slot die to pre-coat a carrier belt, this process bypasses traditional fluidic bottlenecks, enabling the deposition of highly loaded functional inks up to 30,000 centipoise. This capability opens new pathways for depositing dense, high-performance materials that were previously incompatible with digital printing.

The mechanical robustess of this digital deposition method is further highlighted by its tolerance for large particulate matter. Capable of processing particle sizes up to 100 micrometers within wet ink layers of 10 to 15 microns, the system prevents the sedimentation and clogging issues that plague fine-nozzle architectures. This makes it an ideal candidate for printing advanced functional slurries, large-flake graphene, and coarse metallic conductors without sacrificing structural integrity.

Transitioning LIFT to continuous roll-to-roll production requires sophisticated material management to remain economically viable. To prevent massive material waste, the system integrates a continuous ink recycling loop that maintains stable viscosity over long production runs, replacing only the volume deposited onto the substrate. This closed-loop recycling enables the uninterrupted deposition of complex, unbroken circuits over hundreds of meters of flexible substrate.

In this short video, you can learn:
* How pre-inking a carrier belt allows LIFT to process high-viscosity functional inks up to 30,000 centipoise.
* The particle size and wet layer thickness thresholds that distinguish LIFT from traditional inkjet printing.
* The critical role of continuous ink recycling and viscosity control in enabling roll-to-roll digital deposition.

📋 **Clip Abstract**
The speaker discusses the technical operating window of a continuous LIFT printing system, detailing its viscosity limits, wet layer thicknesses, and particle size capabilities. He also explains the necessity of a continuous material recycling loop to maintain ink stability during long roll-to-roll production runs.

🎤 Speaker: Thomas Kolbusch
🏢 Company: Coatema Coating Machinery GmbH
📅 Event: Printed Electronics Innovation Day 2024
📍 Location: TechBlick | Online Platform

🌐 Learn more at the next TechBlick event: https://www.techblick.com

Can laser drying cut your roll-to-roll drying footprint in half while slashing operational costs by 30%?

Traditional thermal drying methods in roll-to-roll (R2R) processing require massive footprints to evaporate solvents from functional coatings. Laser drying offers a highly efficient alternative by targeting electromagnetic energy directly into the coated layers. By utilizing diode and VCSEL (Vertical-Cavity Surface-Emitting Laser) arrays, the system matches the laser wavelength to the absorption spectrum of the wet coating, achieving energy absorption rates exceeding 95% for compatible materials.

This selective energy delivery accelerates both mass and heat transfer within the wet layer, rapidly driving out solvents without heating the bulk substrate or surrounding machine components. The process is particularly powerful for water-based battery anode formulations, where drying kinetics are traditionally slow. By integrating simulation-guided airflow systems, the boundary layers that impede solvent evaporation are broken down, optimizing drying speeds in a compact zone.

The industrial implications of laser-assisted drying are profound, enabling a 50% footprint reduction for drying lines that typically stretch up to 80 meters. Operating costs are cut by up to 30% due to the instantaneous on/off capability of semiconductor lasers, eliminating the unproductive warm-up times and standby energy losses of conventional convection ovens.

In this short video, you can learn:
* How wavelength-selective diode and VCSEL laser arrays achieve over 95% energy absorption in functional coatings.
* The physical mechanisms of accelerated heat and mass transfer that bypass boundary layer thermal resistance.
* The quantitative benefits of laser drying, including a 50% line footprint reduction and a 30% drop in operating expenses.

📋 **Clip Abstract** This clip details the integration of diode and VCSEL laser systems for the continuous roll-to-roll drying of functional wet coatings. It highlights how targeted laser energy absorption and advanced airflow design can slash dryer footprints by half and reduce operational energy costs by 30%.