Mechanical damage. Old fabrics often have tears, cracks and holes caused by use. Flexural strength of these fabrics, tearing and stretching is so greatly weakened, that even under the influence of their own weight, cracks and tears appear in them. Improper storage is also of great importance, folding, hanging and placing, e.g.. causing irreversible kinks and folds.
Light. Under the influence of light, all fabrics are gradually destroyed. Its long-term effect makes, that in the fibers, as well as in dyes, physical and chemical changes occur. The rays absorbed by the fabric cause photochemical reactions and accelerate the oxidation process. The fibers lose their elasticity and mechanical strength, they become brittle and breakable. The degradation process caused by light is generally quite slow, but also usually irreversible. As already mentioned, light not only accelerates the breakdown of the fibres, but it also causes color changes. Undyed fibers turn yellow, and the colored ones fade. This applies not only to synthetic dyes, but also of plant and animal origin. Yellow dyes in particular fade, even the expensive saffron dye. As a result of such changes, color compositions often lose their original meaning. Observations indicate, that the order of fabric sensitivity to color loss is as follows: wool, len, Cotton, million, silk. However, this only gives some orientation.
