The invention relates to a polymer-coated heat-sealable packaging material, to a heat-sterilised package formed from this and to the use of the packaging material. The material comprises a fibre base (4), which is e.g. a packaging board made of bleached pulp, and polymer heat-seal layers (1, 9) located on both sides of this. In accordance with the invention, the package comprises, outside the fibre base, a polymer coating layer (2), which contains white pigment for covering the fibre base from sight, and a second coating layer (8), which contains light-absorbing pigment. A coating layer pigmented grey inside the fibre base, for instance, provides a light shield for the packaged product. The absorbent black pigment may also be located outside the fibre base underneath a white layer in order to stabilise the brightness of the material. The package may be e.g. a food package heat-sterilised in an autoclave, in which yellowing of the fibre-based material has been avoided by means of a white pigment.