In one aspect, the invention relates to a label (1) preferably intended for packages for goods, which label comprises, on one hand, a colouring substance of the type that has the capacity of producing a print by the effect of heat, the colour of which print contrasts with the base colour of the label, and on the other hand an agent having the purpose of, at least partially, destroying the contrast between said colours, if the label is exposed to a tem- perature above a predetermined maximum value, the label having a surface field for a print in the form of a bar-code (3). According to the invention, the label is manufactured from a porous, capil- lary-suctioning material, in addition to which said agent is included in a loading of a substance (7) of the type that is solid at temperatures up to said maximum value, but becomes liquid above the same, the substance loading being located beside the surface field of the bar-code (3). In other aspects, the invention also relates to a package for goods provided with a label, as well as to a method and equipment for the application of labels to packages for goods.