Use of multi-hollow polyester particles as optical brighteners to dry-process fibreboard (MDF)

This work investigates the feasibility to produce a new dry-process fibreboard (medium-density fiberboard, MDF) with pastel colours to be used in construction, furniture, interior claddings, interior design, shopfitting or artistic carpentry. The production of MDF coloured in the bulk with pastel colours is difficult due to the inherent brown colour of wood fibres. So, one of the key points of this study is to increase the fibre brightness using an innovative opacifying filler based on multi-hollow polyester particles as substitute of the common titanium dioxide (TiO 2 ). Fibreboards were produced with TiO 2 and multi-hollow particles (MHP) separately and combined with each other. The colour of panels was evaluated. Relevant properties of the produced boards were evaluated according to European Standards including density, internal bond, modulus of elasticity and bending strength. Boards produced with 10% of TiO 2 and with 5% and 7.5% of MHP incorporated satisfy the objectives in terms of colour and mechanical properties.