| dc.description.abstract | This thesis describes a new investigation into the relationship between the developed
colour intensity of photochromic textiles and the time of UV exposure and also the
time of relaxation. As a result of this relationship the potential of flexible textilebased
sensor constructions which might be used for the identification of radiation
intensity is demonstrated. In addition the differences between photochromic pigment
behaviour in solution and incorporated into prints on textiles are demonstrated.
Differences in the effect of the spectral power distributions of light sources on the
photochromic response are also examined. Bi-exponential functions, which are used
in optical yield (Oy) calculations, have been described to provide a good description
of the kinetics of colour change intensity of photochromic pigments, giving a good
fit. The optical yield of the photochromic reaction Oy is linearly related to the
intensity of illumination E.
The optical yield obtained from the photochromic reaction curves are
described by a kinetic model, which defines the rate of colour change initiated by
external stimulus of UV light. Verification of the kinetic model is demonstrated for
textile sensors with photochromic pigments applied by textile printing and by fibre
mass dyeing.
The thesis also describes a unique instrument developed by author, which
measures colour differences ΔE* and spectral remission curves derived from
photochromic colour change simultaneously with UV irradiation.
In this theses the photochromic behaviour of selected pigments in three
different applications (type of media – textile prints, non-woven textiles and solution
is investigated. | en_US |
