AATCC 15-2009 Colorfastness to Perspiration.
6. Preparation of Reagent
6.1 Prepare the acid perspiration solu- tion by filling a 1 L volumetric flask half full of distilled water. Add the following chemicals and mix to be sure that all chemicals are thoroughly dissolved: 10 ± 0.01 g sodium chloride (NaCl) 1 ± 0.01 g lactic acid, USP 85% 1 ± 0.01 g sodium phosphate, dibasic, anhydrous (Na 2 HPO 4 ) 0.25 ± 0.001 g l-histidine monohydro- chloride (C 6 H 9 N 3 O 2 ⋅HCl⋅H 2 O) Fill the volumetric flask with distilled water to the 1 L mark.
6.2 Test the pH of the solution with a pH meter. If it is not 4.3 ± 0.2 discard it and prepare a new one, making sure all ingredients are weighed accurately. The use of pH test paper is not recommended for this purpose because of its lack of accuracy. 6.3 Do not use perspiration solution that is more than three days old (see 13.5).
7. Verification
7.1 Verification checks on the operation of the test and apparatus should be made routinely and the results kept in a log. The following observations and cor- rective actions are extremely important to avoid incorrect test results.
7.2 Use an in-house perspiration fabric with a mid-range visual grade on the most heavily stained stripe of the multifiber cloth as a calibration specimen and conduct a perspiration test using three specimens. Verification checks should be performed periodically as well as each time a new lot of multifiber or undyed adjacent fabric is used.
7.2.1 Non-uniform color transfer may be due to improper wetout procedures or may be a result of uneven pressure on the specimens due to warped plates in the tester. Check the wet-out procedures to be sure that the balance is accurate and that the procedure is being carefully followed. Check all plates to be sure they are in good condition and not warped.
8. Test Specimens
8.1 Number and size of specimens.
8.1.1 If the specimen to be tested is a fabric, attach a piece of multifiber adja- cent fabric measuring 5 × 5 ± 0.2 cm to the specimen measuring 6 × 6 ± 0.2 cm by sewing along one of the shorter sides, with the multifiber fabric next to the face of the specimen.
8.1.2 If the specimen to be tested is a yarn or loose fiber, take a mass of the yarn or loose fiber approximately equal to one half of the combined mass of the adjacent fabrics. Place it between a 5 × 5 ± 0.2 cm piece of multifiber fabric and a 6 × 6 ± 0.2 cm piece of the non-dyeable fabric, and sew along all four sides.
8.1.3 Do not use multifiber test fabric that has fused edges because it might have thickness variations at the edges which would cause uneven compression during testing.AATCC 15 pdf download.