This invention relates to a novel calixarene derivative which is soluble in organic solvents, films of the novel compound and a method of forming a pattern in a film formed by applying a solution of the novel compound to a substrate.
Calixarenes are cyclic oligomers formed by condensation of phenols and formaldehyde, and some calixarene derivatives can be obtained by substitution reactions after the condensation reaction.
Recent studies have revealed that calixarenes and their derivatives, like cyclodextrine and crown ethers, have the ability to form inclusion compounds. Synthesis of water soluble calixarenes has achieved a limited success, and it is under study to use calixarene derivatives as adsorbents for the recovery of, for example, uranyl ion from seawater or heavy metal ions from waste water.
There is good expectation that calixarenes and their derivatives will serve as advantageous functional materials. From a practical point of view, functional materials are generally required to be soluble in ordinary organic solvents and capable of providing films from solutions. However, known calixarenes and their derivatives are very low in solubilities in organic solvent, viz. below 1 wt %, and hence it is hardly conceivable to practically use these compounds in the form of films as functional materials. J. Am. Chem. Soc., Vol. 111 (1989), 8192-8200 shows to form very thin, monolayer-like films of some calixarene derivatives by using the Langmuir-Blodgett technique, but practical applications of such films will be quite limited.