BS EN ISO 11640:2018 pdf free

BS EN ISO 11640:2018 pdf free.Leather – Tests for colour fastness – Colour fastness to cycles of to-and-frorubbing
Mount a conditioned specimen on the apparatus and stretch it 10 % in the direction of rubbing. If the specimen cannot be extended linearly by 10 %, stretch it less or not at all. If the specimen at 10 % extension does not remain stable during rubbing, stretch it sufficiently to achieve stability. In both of the latter cases, state the extension in the test report.
For normal leathers, attach the weight-piece so that the total mass of the finger is 1 000 gt 35 g (5.1.2).
NOTE Due to the higher friction on suede or nubuck leathers and suede-like or nubuck-like leathers or the flesh side, as well as leather with hair, it can be desirable in such cases to carry out the test with a total mass of 500g±25 g (i.e. without the additional weight-piece).
Attach a piece of conditioned felt to the finger (5.1.2). Place the finger on the leather and carry out the required number of cycles.
Upon completion of the test, lift the finger off the leather test specimen, especally if using wet felts.
If required, repeat the test with another number of cycles with the finger in a fresh position on the specimen (or a new specimen) and after replacing the felt with a new piece.
In the case of a pilling effect on the felt, the test should be repeated. If the pilling effect reoccurs, report this in the test report.
Release the specimen and assess the rubbed area on the specimen and/or on the pieces of felt for change in colour and staining, respectively, as specified in Wetted specimens and pieces of felt shall be dried at ambient temperature before assessment.
Before assessing the change in colour of leathers with a finish, it can be useful to apply a colourless shoe polish and polish lightly with a wollen fabric. Similarly, with suede leathers and similar leathers (for example velour and nubuck) it can be useful to brush with a brush in the direction of the nap.
It is preferable to use the colourless wax emulsion as the shoe polish. In some cases a wax emulsion is unsuitable and a polish consisting of waxes and organic solvents only may have to be used. If a shoe polish is used, this shall be stated in the test report, together with the composition or other details identifying the polish.BS EN ISO 11640 pdf download.