Practical Process of RMG Industry

What is Thermocracking Test Method?

What is Thermocracking Test Method

Thermocracking Test Method

A dyeing prone to thermocracking is aftertreated with a fixative then heat treated and its water fastness tested.  The dye-fibre linkage of reactive dyes can be partially hydrolyzed by the action of heat (thermocracking), resulting in impaired wet fastness properties. Heat can have this action, for example, during thermofixation of dyeings. The detrimental effect of thermocracking can be eliminated by aftertreatment with a cationic fixing agent(Reactive).

Staining of the adjacent fabric and the shade change are assessed.



Material / dyeing
cotton tricot, bleached dyed with:

a:         3.5       %         Cibacron Scarlet 2G-E
            pattern card CEL 3161 Cibacron method 1a/1b 85 °C

b:         4          %         Cibacron Red F-B
            pattern card 3173 Cibacron F/FN method with mixed alkali

The dyeings must always be freshly prepared (hydrolysis during storage !) and washed off as well as possible.

0 - 3     %         fixative

liquor ratio 40 : 1

pH 6 - 6.5 adjusted with acetic acid 80 %

30 min at 40°C

dry without rinsing

Heat treatment
2 min  /  5 min  /  10 min at 200°C in a stenter dryer (no contact heat  !!)

Fastness properties
 ISO 105/E01 water fastness test  (see enclosure)

The shade change of the test speciment and the staining of the adjacent fabric are assessed

Engr. Kh. Mashiur Rahman, Email:

Share :

Facebook Twitter Google+ LinkedIn
0 Comments on "What is Thermocracking Test Method? "

Back To Top