Satoshi Yamamoto, H. Furuya, Kyoji Tsutsui
Jun 13, 2008
Citations
0
Influential Citations
36
Citations
Journal
Crystal Growth & Design
Abstract
This paper reports experimental results of in situ observations of thermochromic processes of two binary mixture systems of 1-(4-hydroxyphenyl)-3-octadecylurea (PU18) + fluoran dye (FD), and 4-hydroxy-N-octadecylbenzamide (PC18) + FD, which were obtained by using FT-IR spectroscopy, reflective optical density, and thermal and X-ray diffraction (XRD) techniques. As the FD, 2′-anilino-6′-di-n- butylaminospiro [isobenzofuran-1(3H),9′-[9H] xanthene]-3-one was employed. We called the long-chain molecules of PU18 and PC18 developers, since the FD molecules became either colored or discolored depending on whether the FD and developer mixture formed a supramolecular complex or the FD and developer were separately crystallized. The supramolecular complex, in which FD was colored by opening its lactone ring, was formed when the molten mixture of FD−developer was quenched from elevated temperature to chilled temperature. The separate crystallization of the FD and developer occurred by heating the supramolecular comp...