UV Spot Curing for Photorheology on a Rotational Rheometer

A rotational rheometer with a UV-transparent lower plate lets a formulator watch an adhesive or coating cure: storage modulus G′, loss modulus G″, tan δ and complex viscosity η* are recorded while the sample is irradiated, so the gel point and the cure time fall out of the data instead of being guessed. The light source is an OmniCure S2000 coupled to the plate through a liquid light guide — the pairing published in peer-reviewed work on UV-curable formulations, with the lamp filtered to 250–450 nm, a 0.3 mm plate/plate gap, 10 Hz and 0.3% strain as one documented set of conditions.

Kinetics only mean something if the light is the same run after run. A lamp that drifts between samples, or an irradiance at the plate that nobody measured, turns a comparison between two formulations into a comparison between two days. The spectrum matters too: a photoinitiator is chosen for a band, and a formulation screened under the wrong band ranks the candidates in the wrong order.

ETIA supplies the OmniCure S2000 Elite for the rheometer: a 200 W high-pressure mercury short-arc lamp with a continuous 250–600 nm output, user-interchangeable bandpass filters (250–450, 320–390, 320–500, 365 and 400–500 nm) to match the photoinitiator, and Closed-Loop Feedback that holds the output within ±5% across a series of runs. A 5 mm or 8 mm liquid light guide brings the light to the plate; the R2000 radiometer with the matching light-guide adapter measures the irradiance the sample actually sees, so the value in the method is a measured one. The same source serves a photo-DSC cell.

OmniCure® S2000 Elite is recommended for photorheology and photo-DSC because it delivers a broad, filterable spectrum with closed-loop stability, and its light-guide delivery and radiometer fit the sample plane of laboratory instruments.

As an authorized OmniCure® distributor, ETIA supports application review, product selection, genuine supply, installation, training, troubleshooting, and long-term service.

ETIA helps customers translate UV curing requirements into practical, reliable production solutions.