AATCC 9-Step Chromatic Transference Scale

AATCC EP 8-2007 pdf free.AATCC 9-Step Chromatic Transference Scale.
5.2 The material exhibiting the transferred color to be evaluated is placed be-hind the card on which the chips aremounted, so that a representative part ofthe colored portion is visible through oneof the circular holes in the column clos-est to it in hue.Before rating a colortransferred to a thin material such aswhite cotton sheeting, the test specimenshould be backed with a number of lay-ers of the clean test cloth. This appliesalso to samples of thin material showingtransferred color mounted on test cards.The color of the cardboard will influencethe judgment of the examiner, unless thecolor of the card is eliminated by addingseveral layers of clean test material be-hind the specimen showing color transfer. This can be done without removingthe sample from the card.With the maskin place, the specimen and the mask arethen moved up or down in this columnuntil the specimen most closely approxi-mates the chroma of one of the chips inthe column. In order to eliminate or minimize the shadow on the specimen through the holes on the Scale.the Scaleshould be held so that the specimen and the Scale are perpendicular to the lightsourcc.
6.1 Evaluations made with a 9-StepChromatic Transference Scale shouldgive essentially the same grades as evalu-ations made with either the Gray Scalefor Staining or the 5-Step ChromaticTransference Scale (see 7.1)
6.2 The 9-StepChromatic Trans-ference Scale is believed to fulfill evalua-tion requirements when the results are analyzed on a statistical basis. It may facilitate evaluations of staining, especially when used by less experiencedraters.
6.3 Reports on grades arrived at by the use of the 9-Step Chromatic TransferenceScale must clearly state that this scalewas used and not the Gray Scale forStaining or the 5-Step Chromatic Transference Scale.
7.Notes
7.1 Availablefrom AATCC，P.O. Box12215，Research Triangle Park NC 27709;tel: 919/549-8141; fax: 919/549-8933; e-mail:orders@aatcc.org.
7.2 Sphere geometry spectrophotometricmcasurements of the chips shall be taken withthe specular component included. A 0°/45°(45°/0°) geometry is an acceptable alternate.The colorimetric data shall be calculatedusing the CIE 1964 10°observer data for Illuminant Des.
7.3 Provision for a grade lower than 1 isprovided for in Nomenclature for SubjectiveRating Processes elsewhere in this MANUAL.Any test specimen which has a change in con-trast decidedly greater than a grade of 1 maybe rated a 0.
7.4 The cleanliness and physical condi-tion of the Scale is extremely important inobtaining consistent results.Inspect theScale frequently for fingerprints and anyother marks. lf the marks are considered tointerfere with the ratings，then the Scaleshould be replaced. The Scale can also bephysically damagedthroughhandling.Again,if the physical damage to the chips;c.g., chipped edges，loose or buckled chips;interferes with the rating process, replace the Scale. At least annually, the Scale should bemeasured on a spectrophotometer or colo-rimeter to ensure that the total color differ-ences are within specification. Measure thecolors on the Scale upon receipt and, usingthe initial color readings,total color differ-ence for each chip should not exceeda AEcxac value of 0.3.A CMC ratio of 2:1should be used (AEcMc computed from thenominal values listed in Table I will likelydiffer from the actual AFcsac obtained frommeasurement of original and stained testcrock squares). Keep the Scale in its casewhen it is not in use.
7.5 See AATCC Evaluation Procedure 9,Visual Assessment of Color Difference ofTextiles, for notes on choice of daylight simulator and illumination level.AATCC EP 8 pdf download.AATCC 9-Step Chromatic Transference Scale