Photochromic dyes

This article describes the defining characteristics of photochromic dyes and highlights the subset of properties that are of greatest commercial importance. It outlines the history of the industrial exploitation of photochromic colorants before moving on to discuss current and potential applications. In doing so, a brief tour of key types of photochromic dye is provided.

Triplet–triplet annihilation upconversion with reversible emission-tunability induced by chemical-stimuli: a remote modulator for photocontrol isomerization

The chemical stimuli-responsive triplet–triplet annihilation upconversion (TTA-UC) system was demonstrated for the first time with high-contrast dual-color UC emission, and this platform was furtherly adopted to induce reversible photoswitching of a photochromic dye remotely under low-energy light excitation at a fixed wavelength.

Diarylethene Dyes

This article introduces the general characteristics of the diarylethene class of photochromic dye and the structural features that make photochromism possible. It touches on the methodologies employed to synthesize these compounds as well as the influences that typical substitution patterns exert on photocoloration. A demonstration is then given of the great diversity pertaining to the potential applications in which researchers are seeking to exploit them as functional colorants.

Naphthopyran Dyes

This article covers the most commercially important type of photochromic dye. It outlines which of its subclasses are of most use and how they are manufactured. The history of the industrial exploitation of this kind of colorant is briefly given before illustrating its versatility with examples of the most useful ways in which photochromic properties can be manipulated by making adjustments to molecular structure.