Determination of Color Fastness to Wash

Experiment No.: 05

Experiment Name: Determination of Color Fastness to Wash.

Introduction:

Color fastness to washing means, A specimen of the textile, in contact with one or two specified adjacent fabrics, is mechanically agitated under described condition of time and temperature in a soap solution, then rinsed and dried. The change in color of the specimen and the staining of the adjacent fabric are assessed with the grey scale.

(This part of ISO 105 specifies methods intended for determining the resistance of the color of textiles of all kinds and in all forms to domestic or commercial laundering procedures used for normal household articles using a reference detergent.

Principle:

A specimen of the textile in contact with specified adjacent fabric or fabrics is laundered, rinsed and dried. Specimens are laundered under appropriate conditions of temperature, alkalinity, bleaching and abrasive action such that the result is obtained in a conveniently short time. The abrasive action is accomplished by the use of a low liquor ratio and an appropriate number of steel balls. The change in color of the specimen and the staining of the adjacent fabric or fabrics are assessed by comparison with the grey scales or instrumentally.

Objective:

1. To learn about color fastness to washing.
2. To learn about the process to test color fastness to washing.

Apparatus & Materials:

1. Suitable Mechanical device which rotating speed of (40 +/- 2) rpm
2. Stainless steel balls (6mm in diameter & Wt = 1gm)
3. Stainless steel container
4. Sewing machine
5. Thermometer
6. Non-dyeable fabric (e.g. Poly propylene0
7. ISO type grey scale for Color changing
8. ISO type grey scale for Color staining
9. Color matching cabinet (Light Box0
10. Adjacent Fabric & Multi-fibre Fabric  

Adjacent Fabric & Multi-fibre Fabric:

DW: Di-acetate, Cotton, Nylon, Polyester, Acrylic, Wool; for 40℃ - 50℃ and certain test at 60℃.

TV: Tri-acetate, Cotton, Nylon, Polyester, Acrylic, Viscose; for certain test at 60℃ and all test at 70℃ and 95℃

Reagents:

1. ECE reference detergent = 4gm/l
2. Sodium perborate tetra hydrate = 1gm/l
3. Distilled water (Grade-3 water)

Test Specimen:

1. If the textile to be tested is fabric:

• Cut out a specimen of (10cm X 4cm) , by sewing along one of the shorter edges, with the multi-fibre adjacent fabric next to the face-side of the specimen.
• Or attach a specimen measuring (10cm X 4cm) between the two single fibre adjacent fabrics by sewing along one of the shorter edges.

2. If the textile to be tested is yarn and loose fibre:

Take a mass of the yarn or loose fibre approximately equal to one half of the combined mass of the adjacent fabric.

• Place it between (10cm X 4cm) pieces of multifibre fabric and (10cm X 4cm) of non-dye able fabric and sew them along all four sides.
• Place it between (10cm X 4cm) pieces of the two specified single fibre fabrics and sew them along four side.

Test Condition:

Test Number	Temperature (℃)	Liquor volume (ml)	Number of steel ball	Time	PH
A2S	40	150	10	30	Not adjusted
B2S	50	150	25	30	Not adjusted
C2S	60	50	25	30	10.5 +/- 0.1

Working Principle:

1. Collecting the sample from bulk and then conditioning for 4.30 to 6 hours.
2. Making a specimen of (10cm X 4cm) in size.
3. Sewing the specimen with multifibre fabric of same size at one corner.
4. Making the solution of 4gm/l detergent and 1gm/l sodium perborate.
5. Putting the specimen with multifibre fabric into the solution in Rotawash machine.
6. Rinsing with hot water respectively.
7. Squeezing with cold water of the sample is done.
8. Then drying is done at a temperature in the air not exceeding 60℃.
9. The stitching is then broken out except on one of the shorter end.
10. Measuring the staining and color change by grey scale and make a test report.

After Treatment:

After soaping treatment, remove the specimen, rinse twice in cold water and then in running cold water under a tap. Squeeze it and air dry at a temperature not exceeding 60℃. The change in color and staining is evaluated with the help of grey scale.

Evaluation:

Compare the contrast between the treated and untreated sample with the changing grey scale and staining of color in the adjacent fabric with the staining grey scale.

Fastness Property Evaluation:

• Grey scale for color change.
• Grey scale for staining

Fastness Grades:

1-5 for all except light fastness

Grade-1: Poor

Grade-5: Excellent

Interpretation of Grade:

1	Very Poor
2	Poor
3	Fair
4	Good
5	Excellent

Range of Limit: 1-5 Grade.

Accuracy(+/-): 0.5

Conclusion:

In this experiment, we get knowledge about color fastness to wash and multi fibre fabric. We learn about how determine color fastness to wash and how use multi fibre fabric.