AATCC

Fibers in Textiles Identification, AATCC Test Method 20-1973, Technical Manual 50 50, American Association of Textile Chemists and Colorists, Research Triangle Park, N.C., 1974. 

ASTM D2020 TAPPI T487, M54 ASTM G21 ASTM G22 ASTM G29 ASTM D3083 AATCC Method 90 AATCC Method 100 ASTMD2017 ASTM D1413... 

Researchers had noted the release of formaldehyde by chemically treated fabric under prolonged hot, humid conditions (85,86). The American Association of Textile Chemists and Colorists (AATCC) Test Method 112 (87), or the sealed-jar test, developed in the United States and used extensively for 25 years, measures the formaldehyde release as a vapor from fabric stored over water in a sealed jar for 20 hours at 49°C. The method can also be carried out for 4 hours at 65°C. Results from this test have been used to eliminate less stable finishes. 

Prior to 1965, it was not unusual for unwashed finished fabrics to release 3—5000 ppm of formaldehyde when tested by an AATCC test method. Formaldehyde release was reduced to the level of 2000 or less by appHcation of DMDHEU or dimethyl olcarhama tes. This level was reduced to approximately 1000 in the mid-1970s. Modification of the DMDHEU system and use of additives demonstrated that release values below 100 ppm were achievable. As of this writing (1997), good commercial finishing ranges between 100 and 200 ppm of formaldehyde release. 

Method 112-1975, Technical Manual, Ameiican Association of Textile Chemists and Coloiists (AATCC), Research Tiiangle Paik, N.C., 1975. 

AATCC Technology Committee on Garment Wet Processing, Text. Chem. Color. 23(1), 23 (1991). 

AATCC methods for determining water repeUency are AATCC 22 (spray test) and AATCC 70 (tumble jar dynamic absorption test). In the spray test, water is sprayed against the taut surface of the test specimen to produce a wetted pattern the size of which depends on the repeUency of the fabric. Evaluation is by comparing the pattern with a series of patterns on a standard chart. The latter method evaluates the percentage by weight of water absorbed by a sample after dynamic exposure to water for a specified period of time. 

Water resistance test methods include AATCC 127 (hydrostatic pressure test), AATCC 42 (impact penetration test), and AATCC 35 (rain test). In the hydrostatic pressure test, a sample is subjected to a column of increasing water pressure until leakage occurs. The impact penetration test requires water to be sprayed on the taut surface of a fabric sample from a height of two feet. The fabric is backed by a blotter of predeterrnined weight, which is reweighed after water penetration. The rain test is similar in principle to the impact penetration test. 

The science of color measurement has been explored by various authors (127,128). AATCC evaluation procedure no. 6 describes a method for instmmental measurement of color of a textile fabric. AATCC evaluation procedure no. 7 may be used to determine the color difference between two fabrics of a similar shade. Instmmentation may be either a spectrophotometer for measuring reflectance versus wavelength, or a colorimeter for measuring tristimulus values under specified illumination. If a spectrophotometer is used, however, the instmment must be equipped with tristimulus integrators capable of producing data in terms of CIE X, Y, and Z tristimulus values. 

Another test method appHcable to textiles is ASTM E313, Indexes of Whiteness and Yellowness of Near-White, Opaque Materials. The method is based on obtaining G, ie, green reflectance, and B, ie, blue reflectance, from X, Y, and Z tristimulus values. Whiteness and yellowness index are then calculated from the G and B values. This method has particular appHcability to measurement of whiteness of bleached textiles. AATCC test method 110 also addresses measurement of the whiteness of textiles. 

Golorfastness. A variety of test methods exist for determining the fastness, or color retention, properties of dyed fabric exposed to various conditions of weathering, laundering, or general exposure associated with the end use of the product. The AATCC Technical Manual should be consulted... 

Fastness to Crocking. Crocking is defined as the transfer of color from the surface of a dyed fabric to another surface by mbbing. AATCC test method no. 8 is a method by which a colored test fabric swatch is fastened to the base of a Crockmeter and mbbed against a white crock test cloth under controlled conditions. Color transfer to the white cloth is evaluated by comparison with the AATCC Chromatic Transference Scale. A similar method, AATCC 116, uses a Rotary Vertical Crockmeter, which requires a smaller area of test fabric than the Crockmeter. 

AATCC Test Method no. 66 describes measurement of recovery angle after placing a crease in a specimen. The specimen is creased by subjecting is to a prescribed load for a length of time. The recovery angle is then measured after a controlled recovery period. Recovery angles of greater than 120° are... 

A second wtinMe-recovery test, AATCC test method no. 128, describes the determination of the appearance of textile fabrics after intentional wrinkling followed by evaluation of appearance in comparison to standard repHcas. A visual rating from 1 (wrinkled) to 5 (smooth) is assigned. This method may be used for both woven and knitted fabrics, whereas the recovery angle method is appHcable only to woven fabrics. 

Water-repeUent fabrics resist wetting or repel waterborne stains they pass AATCC Test Method 22 (Spray Test). 

Water-resistant fabrics protect against water penetration during a light or brief shower and pass AATCC Test Methods 22 and 42 (Impact Penetration Test). 

OU-repeUent fabrics resist wetting by oUy Hquids and repel oilhorne stains. The level of performance of such fabrics is judged by AATCC Test Method 118. 

The rain test simulates the effects of rainfaU the hydrostatic head on the spray controls the intensity of spraying. The repeUency is rated by the weight of water that penetrates the fabric and is absorbed by a blotter mounted behind the fabric at a specific intensity of spraying (AATCC Test Methods 35 and 42 INDA Standard Test 80.2-92). 

OU repeUency is measured by observing a fabric s resistance to wetting by a selected series of numbered test Uquid hydrocarbons with a range of surface tensions. The fabric rating is based on the Uquid that does not wet the fabric surface in a specified time (AATCC Test Method 118 and INDA... 

The hydrostatic-pressure test is performed on fabric mounted under the orifice of a conical weU. The fabric is subjected to increasing water pressure at a constant rate until leakage occurs at three poiats on the fabric s undersurface. The rating is the height of the water head ia centimeters above the fabric (AATCC Test Method 127 INDA Standard Test 80.4-92). 

The dynamic absorption test measures the resistance of fabrics to wetting by water, not the repeUency of the total fabric surface. A weighed portion of fiber, yam, or fabric is tumbled ia water for 20 minutes it is then removed and reweighed to determine the percentage of water absorbed (AATCC Test Method 70). 

Test Methods. Tests for measuting the water and oU repeUency of leather iaclude ASTM and AATCC tests, as weU as tests developed by suppUers. 

In the Spray Test (AATCC Test Method 22), water is sprayed on a taut surface and rating is based on comparison with a standard chart (14). 

In OU RepeUency (AATCC Test Method 118), drops of oUs of various surface tensions are placed on the leather and monitored to absorption (14). 

The 3M Abrasion Test (51) is used to assess the durabUity of a protective fluorochemical finish by evaluating its resistance to abrasion and wear. The surface is abraded with an AATCC crockmeter fitted with sandpaper. 

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