Figure 9. Diazonium salt solution under UV light (λ = 365 nm; top: immediately after dropping the solution onto a filter paper; middle: after 5 seconds; bottom: after 45 seconds). (Photographs: Ducci)

From

Diazotype – A Historical Copying Process

Matthias Ducci

World Journal of Chemical Education. 2021, 9(4), 136-143 doi:10.12691/wjce-9-4-6