AATCC EP 2-2006 Gray Scale for Staining.
5. Use of the Scale
5.1 Provided with the Scale is a mask with three rectangular holes in it. One is labeled “For Evaluating Stained Multifiber,” the second “For Evaluating Crock Squares,” and the third “For Evaluating General Staining,” The cleanliness and physical condition of the Gray Scale is extremely important in obtaining consistent results (see 7.5).
5.2 How the Scale and mask are used will depend on the nature of the stained materials. The following sections are concerned with the creation of a junction, where necessary, between the stained and unstained materials. Place the specimen of the stained mate
5.2.1 Large pieces of stained material. rial side by side with a piece of the un- stained material oriented in the same direction. Take special care to create a sharp junction between the two pieces of material. Place the Gray Scale along the edges of the test specimen and unstained material with the junctions of the Gray Scale and the textiles aligned. Place the “For Evaluating General Staining” mask (Y tristimulus of 53 ± 1) provided with the Scale over the samples and the Scale to normalize the surrounding area (see Fig. 2).
5.2.2 Stained crock specimens. Place the “For Evaluating Crock Squares” mask ( vided with the Scale over the crock Y tristimulus value of 53 ± 1) prosquare with the stained area centered in the mask to normalize surrounding areas. Place the Gray Scale over the mask next to the test specimen.
5.2.3 Multifiber material. Place the specimen of the stained multifiber material and a piece of the unstained multifiber material oriented in the same direction. Take special care to create a sharp junction between the two pieces of material by trimming the stained specimen. Place the Gray Scale along the edges of the test specimen and unstained material with the junctions of the Gray Scale and the textiles aligned. Place the “For Evaluating General Staining” mask ( the Scale over the samples and the Scale Y tristimulus of 53 ± 1) provided with to normalize the surrounding area.
5.2.4 Irregular stains. Select appropriate sized mask and follow instructions in
5.2.1 above. terials with unstained, undyed material of 5.3 Back the stained and unstained mathe same kind to achieve visual opacity. Illuminate the surfaces with a daylight simulator with illumination level at the specimen plane in the range of 10801340 lx (100-125 fc) (see 7.6). The light should be incident upon the surfaces at approximately 45° and the direction of viewing approximately perpendicular to the plane of the surfaces (see Fig. 3). Compare the visual difference between original unstained and stained pieces with the differences represented by the Gray Scale. The grade of the specimen is that number of the Gray Scale which most closely corresponds to the contrast be- tween the original and tested pieces.AATCC EP 2 pdf download.