To obtain a functional polymer having a pressure-sensitive coloring matter, pressure-sensitive paint and pressure-sensitive element which can prevent deterioration of photoresponse due to aggregation of coloring matter when an organic solvent is evaporated and produce a sensor thin film having uniform characteristics.

Since an oxygen extinction coloring matter group included in a pressure-sensitive coloring matter directly bonds with an organic polymer compound having a trimethylsilyl group by a covalent bond, when the solvent is evaporated, the coloring matter cannot form aggregation because molecules of the coloring matter are fixed with the polymer. Therefore, deterioration of photoresponse due to aggregation of coloring matter when an organic solvent is evaporated can be prevented, which is a problem when applying a conventional mix-type pressure-sensitive paint. By mixing a functional polymer with a solvent to prepare a pressure-sensitive paint, a sensor thin film having uniform characteristics can be formed with spray coating or spread coating. In addition, by dissolving a single component into an adequate solvent, a coating liquid suitable for spray coating and spread coating can be obtained with high repeatability.