Thermochromism technology

Advances in military textiles and personal equipment Thermochromic technology... 

Microencapsulation is a revolutionary technology enabling liquids to be treated as solids. The technology was first used to produce carbonless copying paper, but today it is widely used in a number of industrial fields such as medicine, agricultural chemicals, thermochromic materials, cosmetics, and toiletries. 

Among all Fe(II) spin crossover compounds known to date, the extensively studied polymeric [Fe(4-R-l,2,4-triazole)3](anion)2 systems (R=amino, alkyl, hydroxyalkyl) appear to have the greatest potential for technological applications, for example in molecular electronics [1, 24, 25] or as temperature sensors [24, 26]. This arises because of their near-ideal spin crossover characteristics pronounced thermochromism, transition temperatures near room temperature, and large thermal hysteresis [1, 24, 27]. 

Parsley M (1991) Hallcrest handbook of thermochromic liquid crystal technology. Hallcrest, Glenview... 

Carmona N., Herrero-Hernandez E., Llopis J. and ViUegas M.A. (2008), Novel sol-gel reversible thermochromic materials for environmental sensors. Journal of Sol-gel Science and Technology, 47 pp. 31-37. 

M. Parsley, The Halle rest Handbook of Thermochromic Liquid Crystal Technology, Hall-crest Product and Information, Illinois, U.S.A. 1991. 

Mekhilef, S., and Javadi, F.S. (2013) Performance, materials and coating technologies of thermochromic thin films on smart windows. Renew. Sustain. 

Inherently processable conjugated polymers is not only technologically important. There is also a considerable scientific interest in these materials, since they enable the study of conjugated systems in solution and in the melt. Such studies have lead to the discovery of phenomena such as thermochromism and solvatochromism in conductive polymers. 

That what follows is not intended just to give a complete overview of existing ideas, but to filter seminal conceptions and to take up more fundamental ideas. It should be mentioned that solvent relaxation phenomena, i.e., dynamic solvent effects, are omitted On the other hand, recent investigations of thermochromism and solvatochromism in solution have also been considered as a rapidly expanding field applicable to both, easy characterization of solvent properties as well as in technological applications. Such methods can be used to investigate mutual solute-solvent and solvent-solvent interactions for example in case of ions in solutions as well as in ionic liquids. 

HABIs are readily manufactured from accessible starting materials. The biimidazoles in general possess some level of thermochromism, i.e., radicals are formed at elevated temperatures. This has restricted the use of these photoinifiators in certain applications, e.g., where extrusion technology, rather than solvent coating is the manufacturing process. 

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