Technical Bulletin — Cure Kinetics & Jacobs Working Curve (405 nm)

Technical Scope

This technical bulletin provides the quantitative basis for the applied engineering interpretation of FT1 and LB1 Bio fine-tuning strategies.

Applied Engineering Analysis – FT1 & LB1 Bio (405 nm)

Material system: 3Dresyn PEEK-like with FT1 and LB1 Bio fine-tuning additives.
Optical conditions: 405 nm; irradiance levels of 2.2, 4, 6, and 8 mW/cm².
Methodology: Cure-depth mapping, dose-based normalization, and Jacobs working-curve modeling.

How This Bulletin Fits Within the 3Dresyns Framework

Engineering Interpretation

FT1 (photo-accelerant): shifts cure onset toward lower dose by reducing the apparent critical exposure (Ec). It is used primarily to increase printing speed.
LB1 Bio (resolution modifier): improves optical confinement, reducing light bleeding and overcure. It supports higher XY detail and improved dimensional stability.
Dose control is critical: Dose (mJ/cm²) = irradiance (mW/cm²) × exposure time (s). Real irradiance at 405 nm should be verified for reproducible results.

Cure Depth vs. Time (405 nm)

Cure Depth vs. Time at 2.2 mW/cm² (405 nm)

Cure depth vs time at 2.2 mW/cm², 405 nm

Cure Depth vs. Time at 4 mW/cm² (405 nm)

Cure depth vs time at 4 mW/cm², 405 nm

Cure Depth vs. Time at 6 mW/cm² (405 nm)

Cure depth vs time at 6 mW/cm², 405 nm

Cure Depth vs. Time at 8 mW/cm² (405 nm)

Cure depth vs time at 8 mW/cm², 405 nm

Cure Depth vs. Time for Different FT1 and LB1 Bio Concentrations

Cure depth vs time for 2% FT1 and 5% LB1 Bio

Cure depth vs time for 2% FT1 and 10% LB1 Bio

Cure depth vs time for 4% FT1 and 5% LB1 Bio

Dose-Based Analysis (Power–Time Reciprocity)

Dose-based normalization can support first-order cross-printer comparison under matched optical and kinetic conditions.

Dose (mJ/cm²) = irradiance (mW/cm²) × exposure time (s)

Cure depth vs dose at 405 nm

Jacobs Working Curve (Ec and Dp Extraction)

Model: Cd = Dp · ln(E / Ec)

Jacobs working curve at 405 nm

Extracted Parameters (Updated Dataset)

Formulation	Ec (mJ/cm²)	Dp (µm)	R²
2% FT1 + 10% LB1 Bio	19.09	148.25	0.669
4% FT1 + 5% LB1 Bio	19.96	190.21	0.813
2% FT1 + 5% LB1 Bio	23.23	184.20	0.803

Note: These working-curve fits are intended for engineering comparison. Fit quality depends on formulation behavior and the tested dose window.

Validation and Calibration

To translate cure kinetics into real-world dimensional performance, validate the material using calibration geometry and consistent post-processing conditions.

Technical support: info@3dresyns.com