Color fastness measurement ttqc-2 .pptx

Textile engineering,, ttqc-2 , colour fastness lecture

1. # Colorfastness of dyed materials: Today’s consumers are savvier than ever. They not only focus on the ornamental and comfort of textiles, but also on the durability and safety of textiles. They need high-quality products. Market research shows that most of the time consumers buy textiles based on color . Therefore, the ability of the fabric to maintain primary color is one of the most important properties of textiles. 1

2. # Measurement of Color-Fastness: # What is Color-Fastness? Color fastness refers to the resistance of color to fade or bleed of a dyed or printed textile materials to various types of influences e.g. water, heat, light, rubbing, washing, perspiration etc. It is an important indicator to measure the quality of dyeing products. # Categories of Fastness: Producer’s colorfastness User’s colorfastness 2

3. # Classification of Color Fastness: Due to the use of chemicals in the processes of dyeing and finishing, like acid, alkali, oxidants, reductants, etc., and when using in washing, sunlight, rubbing, sweat, high temperature and so on, dyeing textiles may fade or discolor. Therefore, dye /color fastness is diverse, including washing fastness, light fastness, rubbing fastness, perspiration fastness, chlorine fastness, ironing fastness, etc. The color fastness requirements of textiles is different because of their different use and process. For example, the curtain which is less washed requires low Color Fastness, but due to exposure to the sun for a long time, it needs high light- fastness. Summer clothing fabrics should have higher light fastness, washing fastness and perspiration fastness for the reason that they always expose to sun and human body always sweats. 3

4. 4 Co n ti n u e Different countries have set different standards for the different Color Fastness requirements of different textiles. The main standards for Color Fastness are as follows 1. AATCC (American Association of Textile Chemists and Colorists) technical manual: Describes 66 numbers of different Color Fastness tests. SDC (Society of Dyers and Colorists): In 1927, SDC (Europe) made fastness test committee. ISO (International Organization for Standardization): In 1947, ISO made color sub committee. ISO also grades the fastness: For light fastness: 1~8 For other fastness: 1~5

5. 5 # Factors Affecting the Color Fastness Properties The chemical nature of the fiber. For example, cellulosic fibers dyed with reactive or vat dyes will show good fastness properties. Protein fibers dyed with acid mordant and reactive dyes will achieve good fastness properties and so on. That is to say compatibility of dye with the fiber is very important. The molecular structure (e.g.) of a dye molecule: If the dye molecule is larger in size, it will be tightly entrapped inside the inter-polymer chain space of a fiber. Thus the fastness will be better. In addition, the actual situation during use and so on will also have varying degrees of impact on the Color Fastness of textiles.

6. 6 Co n ti n u e Research shows that: As for different types of dyes, we can handle moderately when doing the dyeing process, to improve dye,s Color Fastness. For example, after dyeing textiles, direct dye reacting with a metal salt or cationic fixing agent gives rise to insoluble compounds, so that it can improve direct dye’s wet fastness. After dyeing with disperse dye, polyester fabrics can achieve to remove surface floating color and improve color fastness through a reductive clearing of reductant and an alkaline agent. After dyeing with reactive dye, textiles can improve color fastness to some degree through soap-washing. In addition, different uses and environmental conditions of textiles determine main point and requirement of Color Fastness test.

7. # Types of Colorfastness: Colorfastness tests: Light fastness Washing fastness Rubbing fastness Perspiration fastness Saliva fastness Hot-pressing fastness Water fastness (chlorinated, sea, saline-water) Colorfastness to bleaches and chemicals. Gas fading & weathering fastness 7

8. # Strength tests & Performance tests: • • • • Strength tests: Breaking strength Tearing strength Bursting strength 8 Seam strength ETC Performance tests: Pilling resistance Abrasion resistance Water repellency Flammability Air permeability ETC

9. # How to Test Color Fastness? Because the conditions and the requirements of fabric processing and use are very different, most of the current test methods are simulated according to the working environment and conditions, so the testing methods of color fastness are very extensive. But the international standard organization (ISO), American dyestuff and chemist association (AATCC), Japan (JIS), Britain (BS) and so on many standards, most commonly used tests are wash resistance, light resistance, friction resistance and sweat resistance, ironing resistance, weather resistance and so on. 9

10. Co n ti n u e In the actual work, the testing items are mainly determined according to the final use of the product and the product standard. For example, the wool textile product standard stipulates that the light fastness must be tested, and the knitted underwear, of course, has to be tested for perspiration fastness. Outdoor textiles (such as umbrellas, lamp box cloth, covering materials) are naturally tested for weather fastness. 10

11. 1 # Objects of colorfastness testing: Research Selection of Raw materials for manufacturing Process control Process development Products developments as per standards Specification testing (Analysis) Etc.

12. # Scales for Assessment: 1. Grey Scales Numerical Rating Means 1 Poor 2 Moderate 3 Average 4 Good 5 Excellent 12

13. Grey Scales 13

14. 14 2. Blue Scales Nume r ical Rating Means 1 Little 2 Poor 3 Moderate 4 Average 5 Good 6 Very Good 7 Excellent 8 Maximum

15. Blue scales 15

16. # Testing Standards in World: Standard Corresponding standards organization Country of R e cognition AATCC American Association of Textile Chemists and Colorists American Cou n tries ASTM American Society for Testing and Materials American Cou n tries AS Standards Australia Au s tr a lia and New Zealand BS British Standards Institution UK CAN/CGSB Canadian General Standards Board Canada 16

17. 17 Continue DIN Deutsches Institut Fur Normung Germany ISO International Organization for standardization European countri e s JIS Japanese Standards Association Japan NF Association Trancaise de Normalization Germany US CPSC The US Consumer Product Safety Commission US

18. 1. Color fastness to wash: Color fastness to wash is very important for dyed materials. There are varieties of testing procedure, because: Washing conditions may vary from one country to another. The methods depend on the use of dyed goods. To evaluate repeated washing accelerated test methods are used. 18

19. Continue The degree of fading and staining of dyed materials for washing depends upon the following factors: Temperature range may be from 40°C to 95°C. The type and amount of detergent added to the washing bath. In many testing procedures a standard detergent is used. The extent of mechanical action which can be varied by changing the agitation speed in a washing machine or by adding steel ball to revolving the bath. The washing liquor to goods ratio is 50:01. The hardness of water. The rinsing, drying, or pressing methods used to restore the sample after the washing test. 19

20. 20 1. Principle of Wash Fastness : A spec i men / d y e d mat e r i al i n c o n tac t w i t h specified adjacent fab r i c (M F F) i s launde r e d , ri n s ed a n d d r i e d. The specimen/composite sample is treated under appropriate condition in a chemical bath for recommended time. The abrasive action is accomplished by the use of a liquor ratio and an appropriate number of steel balls. The change in color of the specimen (dyed sample) and the staining of the adjacent fabric (MFF) is assessed by recommended Grey Scales (1-5).

21. 21 Apparatus and Materials : Wa s h -w h e el wit h a t h e rm o s t a t icall y controll e d water bath and rating speed of (40±2) rpm, Stainless steel container (capacity 55±50 ml), Stainless steel ball (dia = 0.6 cm, weight = 1 gm), SDC , Mu l tifi b r e f a bri c (Ac e t a t e / Cotton / Nylon / Polyester / Acrylic / Wool), Thermometer, Sewing machine, Dryer, Color matching cabinet and ISO Scales

22. 22 while the worst is grade 1. # Summary of CFW: It refers to the situation of fade and discoloration of dye textiles when soaping. The main machines used in washing color fastness are Washing Color Fastness Testers . Generally, there are two indicators measured in washing Color Fastness test, including testing fade of original sample and staining of white cloth. Fade of original sample is the color change of dyed textiles before and after soaping. Staining of white cloth is the situation of staining of white cloth which it is soaping together with dyed fabrics. In the testing, dyed sample is stitched together with one or two specified woven fabrics, placed in a soap solution, mechanically stirred at a specified time and temperature, then rinsed and dried. At this moment, dyed sample fades and contaminates the white adjacent fabric. Discoloration of dyed sample and staining of adjacent fabric are measured by gray cards. Water color fastness is divided into 5 grade and 9 files, among which the best is grade 5

23. # Laboratory equipment and materials Figure 1 Washing Color Fastness Tester 1-Drain Pump 2-Heating Protector 3-Passive Gear 4-Motor 5-Reducer 6-Motor Vice Gear 7-Drainage Interface 8-Active Gear 9-Rotating Frame 10-Test Cup 11-Studio Temperature Controller 12-Time Relay 13-Buzzer 14-Preheating Room Temperature Controller 15-Drainage Switch 16-Door Cover 17-Power Switch 18-Insulation 19-Temperature Sensor 20-Tubular Heater 21-Drainage Pipe 22-Drain Pipe Interface 23-Water Pipe 24-Wheel 23

24. 24 Continue Reagents : Reference detergent Sodium Carbonate / Soda Ash Distilled water (Grade - 3) and Etc. * Test specimen : Cut a sample of dyed goods 1 cm × 4 cm a n d sew i t wi t h s a me size multifibre fabric. This is the composite test sample.

25. 25 Continue Test procedure : (ISO recommendation No. 1-5) ISO-105-CO1: Composite sample is treated in a wash wheel for 30 minutes at (40±2)°C with 5 g/l standard soap. Evaluation : Compare the contrast between the treated and untreated sample with Grey Scales for changing color of dyed sample & staining of adjacent fabric in a color matching cabinet.

26. Continue ⭠ Specimen Compos i t e test sa m p l e ⭠ Adjacen t fabric (s i ngle o r d o u ble) 1 c m X 4 c m Mu l t ifibre F a b r i c (I S O ) A c e t a t e C o t t o n N y l o n P o l y e s t a r A c r y l i c W o o l Stee l ba l l D i a = . 6 c m & we i gh t = 1g m 26

27. 27 Continue Test Temperatu re ° C Time (Minu t e) Steel Ball Chemicals ISO-105-CO1 40 30 00 Soap (5 g/l) ISO-105-CO2 50 45 00 Soap (5 g/l) ISO-105-CO3 60 30 00 Soap (5 g/l) + Soda 2 g/l ISO-105-CO4 95 30 10 Soap (5 g/l) + Soda 2 g/l ISO-105-CO5 95 240 10 Soap (5 g/l) + Soda 2 g/l

28. 28 Continue Numerical rating for color changing is the shade and staining to adjacent fabric. Number of method used. Reporting Format : Test Description Result Color fastness to wash (ISO-105-CO3) Grade Color change in shade staining in Acetate 4 Color change in shade staining in Cotton 4 Color change in shade staining in Polyamide 4 Color change in shade staining in Polyester 4-5 Color change in shade staining in Acrylic 4-5 Color change in shade staining in Wool 4

29. 2. Color Fastness to Rubbing (dry + wet) Principle : This test is designed to determine the degree of color which may be transferred from the surface of a colored fabric to a specific test cloth for rubbing ( dry + wet ). Equipment : Crock meter Cotton rubbing cotton Grey Scale Stop watch and Color matching cabinet. 29

30. Manual Crock-meter: 30

31. # Electronic Crockmeter: 31

32. Continue: Size of fabric : 14 cm × 5 cm two pieces of sample (one warp direction/wale direction & other weft/course direction). meter. Test procedure : Lock th e t est s p e c ime n onto t h e ba s e of th e crock Using the spinal spring clip, set 5 cm × 5 cm of the white cotton fabric to the finger of the crock meter. (10 × 10 sec). 32 with grey scale. Lower the covered finger on the test sample. Turn hand crank at the rate of one turn per second Remove the white rubbing test cloth and evaluate Evalua t i o n : Comp a r e t he c ontra s t b et we en h e treated and untreated white rubbing cloth with grey scale and rated 1-5.

33. 33 3.Color Fastness to Perspiration (Alkaline + Acidic) • Principle : The garments which come into contact with the body where perspiration is heavy may suffer serious local discoloration. This test is intended to determine the resistance of color of dyed textile to the action of acidic and alkaline perspiration. Equipment : Perspiration tester Oven, maintained at 37±2°C temperature SDC, Multifibres test fabric Grey scale Color matching chamber Acidic & alkaline solution and Glass or Acrylic plate. Weight

34. Perspiration process: 34

35. Continue 35

36. Continue: Sample size : 10 cm × 4 cm. Reagent : Materials Alkaline Acidic L-histadine mono-hydrochloric hydrate (C 6 H 4 O 2 N 3 HCl·H 2 O) 0.5gm 0.5 gm Sodium Chloride (NaCl) 5.0 gm 5.0 gm Disodium hydrogen ortho phosphate dihydrate (Na 2 HPO 4 2H 2 O) 2.5 gm 2.2 gm Distilled water 1 L 1 L P H (Adjusted with 0·1 N NaOH) P H = 8 P H = 5.5 36

37. Continue: Test procedure : Wet-out the composite test sample in mentioned alkaline or acidic solution at room temperature. M: L ratio 1:50 and leave for 30 minutes. Pour off excess solution and place the composite sample between two glass plate or acrylic plate under a pressure of 4.5 Kg and place in an oven for 4 hours at (37±2)°C temperature. 37 air not exceeding 60°C. Remove the specimen and hang to dry in warm Evaluation : Evaluation is done by grey scale in a color matching cabinet and rated from 1 to 5.

38. 4. Color Fastness to Light * Color fastness to light : This test measures the resistance to fading of dyed textile when exposed to day-light. The test sample is exposed to light for a certain time (24 hrs, 36 hrs, 48 hrs, 72 hrs, -----------etc) or by customer demand, and compare the change with original unexposed sample. The changes are assessed by Blue Scales (1-8). 38

39. Light-fastness Tester 39

40. Continue: Procedure: The sample is cut and should be exposed (1/2 covered and ½ exposed) together with standard dyed wool samples (1-8) as required period of time. The standard and the specimen mounted in a frame. The composite sample must be protected from rain. Evaluation : Evaluation is made numerically by European/ American blue Scales (1-8). 40

41. 41 Continue: # Std. Dyed Wool (References) Preparation: F a stn e ss Rating Dyes CI Number 1 Acilan Brilliant Blue FFR Acid Blue 104 2 Acilan Brilliant Blue FFB Acid Blue 109 3 Coomassie Blue R Acid Blue 83 4 Supramine Blue EG Acid Blue121 5 Solway Blue RN Acid Blue 47 6 Alizarine Light Blue 4GL Acid Blue 23 7 Soledon Blue 4BC powder A.Solvent Blue 5 8 Indigosol Blue AGG Sol. Vat Blue 8

42. 5. Colorfastness to Hot Pressing: A. Principle: Determination of the resistance of the color of dyed textiles to ironing and pressing on the hot cylinders. B. Apparatus and Materials: a) H eating devic e t hat can p ut a p r e s sure on t he specimen of 4 kPa. b) A smooth asbestos sheet (3-6 mm thickness) c) Wool flannel (approx. 260 g/m2, 3 mm thickness) d) A piece of undyed, bleached and mercerized cotton cloth e) Grey scales f) Standard color matching cabinet g) Distilled water h) Etc 42

43. Conti n ue: C. Test Specimen: Cut 10 cm x 4 cm specimen from each fabric sample. D. Test Procedure : i) Condition the samples in standard atmosphere of 21±1ºC and 65±2ºC RH before testing. ii) Then select the specified temperature as follows: 110 ±2ºC 150 ±2ºC 200 ±2ºC 43

44. 44 Conti n ue: iii) Dry Pressing: a) Place the dry specimen on top of the cotton cloth covering the wool flannel pad. b) Lower the top plate of the heating device and leave the test specimen for 15 sec at the recommended pressing temperature. iv) Damp Pressing: a) R e peat iii( a ) and s o ak t o 1 00 % pick - up of a pie c e of cott o n a d jac e n t fabri c i n di s till e d water. b) Place the soaked cotton fabric on top of the dry test specimen and repeat iii(b).

45. Continue: V) Wet Pressing: a) Soak the test specimen and a piece of cotton adjacent fabric in distilled water and squeeze it to maintain 100% pickup. b) Place the wet test specimen on top of the dry cotton cloth covering the wool flannel pad and repeat iii(b). E. Evaluation. a) Numerically rate the color change immediately after testing and again after 4 hrs. in std. atmosphere and std. light using the Grey Scales (1-5). 45

46. 46 Continue: b) Numerically rate the staining of the more heavily stained side of the cotton adjacent fabric compared with original fabric under std. light using Grey scales (1-5) for staining. G. Test Report: i. Mention the testing temperature ii. Test condition (dry, damp, wet) iii. Numerical rating after testing and after 4 hrs. iv . R e port t h e n u merical r a t in g fo r t h e staining of cotton adjacent fabric.

47. Continue: # Reporting Format: Sl # Description of Test Test Result 1 Colorfastness to hot pressing Condition 2 Method followed: ISO105X11:1994 Standard 3 Grade: (1-5) Accuracy ± 0.5 Color change in the specimen 3-4 Staining to Adjacent Cotton Fabric 4 4 Interpretation of Grade: 5= Excellent, 4= Good, 3=Average, 2=Poor, 1=V.Poor 47

48. 6. Colorfastness to gas fading: Fig: Gas fading Chamber: 48 Nitrous oxide is always present in our atmosphere which is a result of burning fumes. Colorfastness can be affected by this chemical, in this chamber, clothes are exposed to nitrous oxide and evaluated for color fasting strength.

49. There is also a standard scale to measure color fastness correctly, it ranges from 5 to 1 . 5: on this scale means no color change after exposure to all kinds of agitating agents, whereas grade 1: involves a large amount of change in the original color of clothing. Scale for colorfastness to light varies a little; it ranges from 9 to 1, 9 being the best score whereas 1 is the poorest score. 49