Art Spectrum Yupo Pads Available in 85gsm, 158gsm, 200gsm and 410gsm. Acid Free, ultra smooth bright white paper. Suitable for alcohol/spirit based inks, watercolours, and acrylics. 10 sheet count Sizes A4 and A3 Synthetic Yupo paper consists of petroleum-derived polypropylene resin and inorganic filler (calcium carbonate) A synthetic (polypropylene) substrate is born with a non-porous surface that repels water. Yupo has an ultra-smooth finish, a non-absorbent substrate that dramatically changes the way you paint, print or draw and has superior strength. Yupo is 100% tree-free. Yupo papers are fully recyclable, as the waste can be reclaimed as resin. Yupo synthetic papers generate no detectable amounts of sulphur, chlorine, nitrogen or dioxin gases.