This document specifies general principles on colour fastness evaluation tests for leather, as listed in Annex A.
Procedures included in this document are common to most of the fastness test methods.
This document provides a common basis for testing and reporting colour fastness. The uses and limitations of the methods are pointed out, several terms are defined, an outline of the drafting of the methods is given and the contents of the clauses describing the methods are discussed.
Procedures common to a number of the methods are discussed briefly.
Colour fastness means the resistance of the colour to the different agents to which these materials can be exposed during manufacture and their subsequent use.
The change in colour of leather and staining of undyed adjacent fabrics or other materials are assessed as fastness ratings.
Other visible changes in the leather under test, for example surface appearance, change in gloss or shrinkage, are considered as separate properties and reported as such.
The leather fastness test methods can be used not only for assessing leather and related materials, such as coated leather and leather board, but also for the eventual assessment of the colour fastness of leather dyes. When such a method is so used, the dye is applied to a specified retanned leather or crust leather in defined depths of colour by stated procedures and the material is then tested in the usual way.