MAJOR Ubaid-Ur-Rehman i

Colorfastness: Resistance to fading; i.e., the property of a dye to retain its color when the dyed (or printed) textile material is exposed to conditions or agents such as light, perspiration, atmospheric gases, or washing that can remove or destroy the color. A dye may be reasonably fast to one agent and only moderately fast to another. Degree of fastness of color is tested by standard procedures. Textile materials often must meet certain fastness specifications for a particular use.

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Colorfastness is the resistance of a material to change in any of its colorant to adjacent materials for both , as a result of the exposure of the material to any environment that might be encountered during the processing , testing , storage or use of the material.

The outstandingly important property of a dyed fabric is the fastness of its shade . A number of tests are necessary to cover all the properties of any one dye . The tests may be divided into those consumer significance such as light , washing & salt-water staining , & those concerning the producer only , such as cross-dyeing , bleaching & shrink resist treatments.

Colorfastness To Water : Colorfastness to water can be define as resistance of color to immersion in water .

Now before discussing the testing method in detail we first must know what is meant by ISO & AATCC . ISO stands for International Organization for Standards & AATCC stands for American Association of Textile Chemists and Colorists .

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MAJOR Ubaid-Ur-Rehman ii

Development Of Method : AATCC Method 107 – 1997 was developed in 1962 by AATCC committee RA23 it was revised ; 1967, 1968, 1972, 1981 ; reaffirmed 1975, 1978, 1989; editorially revised 1983, 1985, 1994, 2001; editorially revised & reaffirmed 1986, 1991, 1997, 2002 . Technically it is equivalent to ISO 105-E01.

Purpose and scope : This test method is designed to measure resistance to water of a dyed, printed, or otherwise colored textile yarns & fabrics. Distilled water or deionized water is used in this test method because natural (tap) water is variable in composition .

Principle : The specimen , backed by multifiber test fabric , is immersed in water under specified conditions of temperature & time , and then placed between glass or plastic plates under specified conditions of pressure , temperature & time . The change in color of the specimen and the staining of the attached multifiber test fabric are observed .

Apparatus & Materials Required : AATCC Perspiration tester , perspirometer or equivalent device (plastic or glass plates which are available with the equipment ) . Drying oven convection , multifiber test fabric No.1 or No.10 , AATCC Chromatic Transference scale , AATCC Gray Scale for Color Change & Gray Scale for Staining , Wringer , freshly boiled distilled water or deionized water from an ion-exchange device , test specimens Colored specimens of 60*60 mm ± 2mm (2.25*2.25in.) backed with multifiber test fabric .

Procedure : The standard procedure to be follow in this experiment is as follows .

Immerse the test specimen in the test solution at room temperature with occasional agitation to ensure thorough wetting out (approximately 15 min generally required for average fabrics .

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MAJOR Ubaid-Ur-Rehman iii

Remove the test specimen from the test solution and only pass between squeeze rolls (wringer) to remove excess liquor when the wet weight of the test specimen is more than 3 times its dry weight .whenever possible , the wet weight should be 2.5-3.5times the dry weight .

Place the test specimen between glass or plastic plates and insert in the specimen unit of the perspiration tester. Adjust the perspiration tester to produce a pressure of 4.5KG(10 lb) on the test specimen .

Heat the loaded specimen unit in an oven at 38±1°C(100±2°F) for 18h. remove specimen from unit and complete drying by hanging in air at room temperature. Do not press dry.

Evaluation Method For Color Change : Rate the effect on the color of the test specimens by the gray scale for color change .

Grade 5__negligible or no change as shown in gray scale step 5.

Grade 4.5__change in color equivalent to gray scale step 4-5.

Grade 4__change in color equivalent to gray scale step 4. Grade 3.5__change in color equivalent to gray scale step

3-4. Grade 3__change in color equivalent to gray scale step 3. Grade 2.5__change in color equivalent to gray scale step

2-3. Grade 2__change in color equivalent to gray scale step 2. Grade 1.5__change in color equivalent to gray scale step

1-2. Grade 1__change in color equivalent to gray scale step 1.

Evaluation Method For Staining : Rate the staining of the multifiber test fabric by the AATCC chromatic transference scale or the gray scale for staining . Report which classification scale is used .

Grade 5__negligible or no color transfer.

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MAJOR Ubaid-Ur-Rehman iv

Grade 4.5__color transfer equivalent to step 4-5 on the gray scale for staining or row 4.5 on the 9-step AATCC chromatic transference scale.

Grade 4__color transfer equivalent to step 4 on the gray scale for staining or row 4 on the 9-step AATCC chromatic transference scale.

Grade 3.5__color transfer equivalent to step 3-4 on the gray scale for staining or row 3.5 on the 9-step AATCC chromatic transference scale.

Crade 3__color transfer equivalent to step 3 on the gray scale for staining or row 3 on the 9-step AATCC chromatic transference scale.

Grade 2.5__color transfer equivalent to step 2-3 on the gray scale for staining or row 2.5 on the 9-step AATCC chromatic transference scale.

Grade 2__color transfer equivalent to step 2 on the gray scale for staining or row 2 on the 9-step AATCC chromatic transference scale.

Grade 1.5__color transfer equivalent to step 1-2 on the gray scale for staining or row 1.5 on the 9-step AATCC chromatic transference scale.

Grade 1__color transfer equivalent to step 1 on the gray scale for staining or row 1 on the 9-step AATCC chromatic transference scale.

After discussing the method in detail we will now discuss some important apparatus of the method & how to use them in experiment .

AATCC Perspiration Tester : AATCC perspiration tester consists of 21 glass or plastic plates & dual plates with compensating springs . To use it experiment put all 21 glass or plastic plates into the unit regardless of the number of specimens. After the final glass or plastic plate is put in position on top, set the dual plates with compensating springs in position . Place the 3.6 kg (8.0 lb) weight on top making a total of 4.5 kg (10.0 lb) under the pressure plate . lock the pressure plate in position by turning the thumb-

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MAJOR Ubaid-Ur-Rehman v

screws. Remove the weight. Place the unit in the oven on its side, so that the plates and the specimens are vertical.

Grey Scale For Assessing Change In Shade :This Grey Scale is for assessing the degree of change in shade caused to a dyed Textile fabric / yarn in color fastness tests . For example, the chnage of shade of wool , polyester cotton etc fabrics in the water , wash fastness , per spiration fastness , etc.

The scale consists of nine pairs of gray color chips each representing a visual difference and contrast.

The fastness rating goes step-wise from:

Note 5 = no visual change (best rating) to Note 1 = a large visual change (worst rating).

The gray scale has the 9 possible values:5, 4-5, 4, 3-4, 3, 2-3, 2, 1-2, 1.

Grey Scale For Assessing Staining : This Grey Scale is for assessing the degree of staining caused by a dyed Textile / yarn in color fastness tests. For example, the staining of polyester & cotton fabrics in the wash fastness, water , perspiration fastness, etc.

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MAJOR Ubaid-Ur-Rehman vi

The scale consists of nine pairs of gray color chips each representing a visual difference and contrast.

The fastness rating goes step-wise from:

Note 5 = no visual change (best rating) to Note 1 = a large visual change (worst rating).

The grey scale has the 9 possible values:5, 4-5, 4, 3-4, 3, 2-3, 2, 1-2, 1.

References :

Dyeing & Chemical Technology Of Textile Fibers By E.R.Trotman .

http://www.thesmarttime.com/testing/testing-procedures-34.htm .

http://clothinger.blog.163.com/blog/static/2569718820075137393979/

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