This board (Fig. 1.15) is made exclusively from unbleached chemical pulp.The base board is brown in colour. This product is also known as solid unbleachedsulphate. To achieve a white surface, it can be coated with a white mineralpigment coating, sometimes in combination with a layer of bleached white fibresunder the coating.SUB is used where there is a high strength requirement in terms of punctureand tear resistance and/or good wet strength is required such as for bottle or canmultipacks and as a base for liquid packaging.