It is known from the literature that two metastable long-lived
complexes are formed in a TC composite as a result of two
competitive reactions, dyeedeveloper and solventedeveloper[10].
At low temperatures dyeedeveloper interactions prevail which
forms coloured dyeedeveloper complexes. When at higher
temperatures the solvent melts, solventedeveloper interactions
destroy the dyeedeveloper complexes and TC composite trans-forms into its colourless state. Coloured complexes prevail at
temperatures below T4 and colourless complexes above T2
regardless of thermal history of the sample. Between these two
temperatures the system undergoes changes which depend on its
thermal history.