Colour Ageing in Acrylic Resin Plates and Natural Minerals on the Façade after 10 Years of Sun Exposure in the Marine Environment

Abstract

The synthetic material developed by Dupont in 1963 for solid surfaces has been used since its origin for numerous applications. One of the most popular ones in the last decade is as a finishing layer on façades. The first references that contemplated this use on the outside were the Seeko’o hotel in Bordeaux executed in 2007 and the refurbishment of the 7700 m2 shell of the Hôtel Ivoire congress centre in Abidjan (Ivory Coast) in 2009. In Spain, the first example of the installation of this material is the rehabilitation of the main building of the La Rotonda de la Playa de San Juan urbanisation in Alicante, designed in 1965 by the architect Juan Guardiola Gaya and rehabilitated in 2010 by Miguel Salvador Landmann. Ten years later, our research is focused on the study of the colour ageing of the acrylic resin and natural mineral sheets on each of its façades, with different orientations and exposure to sea and wind. To this end, it has been studied the solar radiation of the surfaces, the wind exposure of their façades and tests with a tele-spectroradiometer has been carried out. The study makes it possible to quantify the differences in colour in all of them and to state that the combination of wind and radiation is the main atmospheric agent causing the degradation.

Contribution to the Understanding of the Colour Change in Bluish-Grey Limestones

“…Other vestigial phases are present, namely pyrite in the bluish-grey (3) and possibly goethite in brown (2); no further minerals that could be responsible for the colour of the limestone were identified. As already said, the exposure to atmospheric conditions results in stone ageing [9,10]. The summary of the atmospheric conditions [57] observed in the period of the limestone experiment (in the rooftop terrace) is shown in Table 2.…”

“…The constant exposure to natural weathering (solar radiation, temperature variation, water percolation, air pollution, biological agents) causes several types of damage including physical weathering, such as microcracking and disintegration, and chemical weathering, such as discoloration and dissolution of component mineral grains [9][10][11][12][13]. Limestone catastrophic deterioration results in black crusts, scaling, flaking, blistering, granular disintegration, and alveoli [14], making colour alteration one of the most evident signs of deterioration in heritage materials.…”