B.Sc Thesis & Research

Whiteness Index & Absorbency of Cotton Knitted Fabric Using Different Bleaching Agents

Comparing H₂O₂, Sodium Hypochlorite, and Sodium Perborate on 100% cotton single jersey fabric.

Port City International UniversityTextile EngineeringMarch 2021

Study Overview

Fabric

100% Cotton S/J

GSM: 160

Samples

9 Samples

5g each

Agents Tested

3 Bleaching Agents

Oxidative bleaching

Tests Conducted

3 Test Types

Whiteness, Drop, Immersion

Results & Findings

H₂O₂

Hydrogen Peroxide

Whiteness Index (CIE)67.46%

Drop Test

2.15 sec

Immersion Test

3.04 sec

Hand Feel

No stiffness

Verdict

Best Overall

Whiteness Comparison

H₂O₂67.46%

Na₂HOCl49.98%

NaH₂BO₄33.24%

Methodology

01100% cotton S/J fabric cut into 9 samples of 5g each

02Bleached at respective temp & time in sample dyeing machine

03Whiteness measured via spectrophotometer (AATCC 110)

04Absorbency tested by drop test & immersion test

Conclusion

H₂O₂ outperforms all agents across every measure.

Hydrogen peroxide achieved the highest whiteness at 67.46%, fastest absorbency, and softest hand feel — making it the clear choice for industrial cotton bleaching.

◎

67.46% whiteness — highest among all three agents

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Fastest absorbency — 3.04 sec average immersion time

◇

No fabric stiffness — best hand feel result

⬡

Eco-friendly reaction products — reduces pollution