2. Prepared by
Md. Rahmat Ullah
B.Sc in Textile Engineering (BUFT)
M.Sc in Environmental Science and Management (BUP)
Sr. Textile Testing Engineer(Colorfastness & Flammability)
TUV Rheinland Bangladesh .Pvt. Ltd.
3. Give a look for today’s session
• Scope & Principle
• Apparatus
• Reagents
• Value of “V= ml….?”
• Test specimen
• Procedure
• Test report
4. Scope & principle
• Scope : This part of ISO Specifies a method for determining the
resistance of the color of textile of all kinds and in all forms to the
action of active chlorine in concentrations such as are used to disinfect
swimming-pool water. Three alternative test conditions are specified.
The active chlorine concentration of 50mg/l and 100 mg/l are intended
for swimwear. The active chlorine concentration of 20mg/l are
intended for accessories such as beach robes and towels.
• Principle : A specimen of the textile is treated with a weak chlorine
solution of a given concentration and dried. The change in color of the
specimen is assessed by comparison with the grey scale or
instrumentally. Three alternative test condition are specified.
5. Apparatus
• Suitable mechanical device
• pH meter
• Grey scale for assessing change in color
• Spectrophotometer
• Analytical balance
7. Value of “v= ml…”
Step 1:
• Solution 1: 20 ml of Sodium hypochlorite (NaOCl) solution to 1L
• Solution 2: 14.35 g of Potassium dihydrogenphosphate (KH2PO4) per L.
• Solution 3: 20.05 g of Disodium hydrogenphosphate dihydrate (Na2HPO4.2H2O) or disodium hydrogenphosphate
dodecahydrate (Na2HPO4.12H2O) per L.
Step 2:
Strarch 1 gm (Boiled Water)
25 ml of solution 1 + Potassium iodide (KI) 1 gm + starch Boiled solution(as a indicator)
Titrate the liberated iodine with Sodium thiosulfate Solution ( Na2S2O3)=0.1 mol/l.
Let the Volume of Sodium thiosulfate Solution ( Na2S2O3) required be “V= ml….?”
pH = 7.50 ± 0.05.(If necessary,adjust pH using sodium hydroxide (NaOH) or acetic acid (CH3COOH)=0.1 mol/l )
8. Value of “v= ml…”
Containing 100mg of active chlorine per litre :
• 705.0/V ml Solution 1
• 100ml solution 2
• 500ml solution 3 (dilute to 1 L. with grade 3 water)
Containing 50mg of active chlorine per litre :
• 705.0/2V ml Solution 1
• 100ml solution 2
• 500ml solution 3 (dilute to 1 L. with grade 3 water
Containing 20mg of active chlorine per litre :
• 705.0/5V ml Solution 1
• 100ml solution 2
• 500ml solution 3 (dilute to 1 L. with grade 3 water
9. Test Specimen
• If the textile to be tested is fabric, use a specimen measuring.
• If the textile to be tested is yarn, knit it into fabric and use a specimen measuring.
• If the textile to be tested is loose fibre, comb and compress enough of it to form a
sheet measuring, determine the mass of the fiber and sew it onto a piece of
polyester or polypropylene cloth to support the fiber.
• Sample Size : (40 ± 2) mm x (100 ± 2) mm
10. Procedure
• Each specimen shall be tested in a separate container in the mechanical device.
Immerse the specimen in the sodium hypochlorite solution of liquor ratio
100:1,ensuring that the specimen is thoroughly wetted. Close the container and
agitate at (27 ± 2)° C for 1hour in darkness.
• Remove the specimen from the container, squeeze or hydroextract it, and dry it by
hanging it in air at room temperature in subdued light.
• Assess the change in color of each specimen with reference to the original
specimen by comparison with grey scale or instrumentally.
11. Test Report
• A reference to this part of ISO 105(ISO 105-EO3)
• All details necessary for the identification of the sample tested
• The numerical grey scale rating or instrument assessment for the change in color of
each specimen
• The concentration of active chlorine used
