UPF Evaluation of Fabric Products such as Functional Masks

Significance of the Topic

Ultraviolet Protection Factor (UPF) is a critical index for assessing how effectively textiles shield against harmful UV radiation, which can cause skin aging, blemishes, and cancer. Accurate UPF determination is essential in textile development, quality control, and regulatory compliance to ensure consumer safety and product performance.

Objectives and Study Overview

This study aimed to identify and eliminate the effect of fluorescence in fabric samples to obtain correct UPF values. Eight textile products (six mask types, one cap, one towel) were evaluated for fluorescence interference and UV transmittance. UPF values were then calculated according to multiple national and international standards.

Methodology and Instrumentation

A two‐step analytical approach was employed

• Fluorescence screening with the RF‐6000 Spectrofluorophotometer (excitation 280–400 nm, emission 280–550 nm, 3D scan) to detect samples emitting fluorescence, which can inflate transmittance readings.
• UV transmittance measurement using the UV‐2600i UV‐Vis Spectrophotometer (280–400 nm) fitted with a bandpass filter cutting wavelengths >431 nm to exclude fluorescence.
• UPF calculation performed automatically with LabSolutions UV‐Vis UPF software, supporting JIS, EN, DIN, AS/NZS, AATCC, and Chinese standards.
• Sample set: two white masks (commercial and functional), four colored functional masks, a black cap, and a black towel.

Main Results and Discussion

Fluorescence was observed in two white masks around 350–450 nm, confirming the need for fluorescence exclusion. Transmission spectra revealed that commercial and white functional masks allowed higher UV passage, while khaki, navy, gray masks and black textiles offered enhanced UV blocking. Calculated UPF values varied by standard: the black towel exceeded UPF 50+, the khaki mask approached 80, and the professional mask registered around UPF 60. Discrepancies between JIS, EN/DIN, and AS/NZS indications highlighted standard‐specific calculation rules and rounding conventions.

Benefits and Practical Applications

Correcting for fluorescence ensures reliable UPF values for product development and certification. Automated UPF calculation accelerates laboratory workflows and guarantees compliance with diverse regulatory requirements. This approach aids textile manufacturers, testing laboratories, and quality assurance teams in delivering transparent UV protection claims.

Future Trends and Opportunities

Integration of fluorescence correction in portable spectrometers could enable in-field UPF validation. Advances in software algorithms may streamline multi‐standard reporting and real-time data analytics. Emerging smart textiles with embedded UV sensors will benefit from robust calibration protocols that account for sample fluorescence.

Conclusion

Screening for fluorescence with the RF‐6000 and applying a bandpass filter during UV-Vis transmittance measurement allows precise UPF determination. LabSolutions UV-Vis UPF software supports automated calculation across global standards, improving accuracy and efficiency in UV protection assessment.

Reference

Kawahara K, Sobue K. UPF Evaluation of Fabric Products such as Functional Masks using RF-6000 and UV-2600i Spectrophotometers. Shimadzu Application News 01-00032-EN, Sep. 2021.