Development of Photochromic Wood Material by Microcapsules

Abstract

To develop a smart, colour-changing wood material, photochromic microcapsules were incorporated into coatings while painting veneered plywood. The properties of microcapsules and coatings were investigated. The colour-changing behaviour of the photochromic wood material in response to sunlight exposure was evaluated. The microcapsules exhibited sensitive colour-changing function and had good thermal stability. The prepared photochromic wood material spontaneously altered its appearance from the veneer colour to a blue colour following intensity changes of the sunlight exposure on the sample. The incorporation of microcapsules had no obvious effect on coating adhesion, but it obviously reduced coating wearability. With the microcapsule content increasing from 2.5% to 10% (of the coating weight), the colour difference (ΔE) of photochromic wood stimulated by sunlight linearly increased from 7.45 to 21.58. The performance of the prepared photochromic wood material can be adjusted by controlling the addition amount of microcapsules.