Dyeing & Printing-I question paper (WPE 341) from the 2015 Level-3 Term-I finals at BUTEX affiliated colleges, 105 marks. Includes dye classification, direct dye after treatments, vatting reactions, reactive dye protein chemistry, and winch dyeing machine parts.
Level-3 Term-I, Final Exám-2015
Subject: Dyeing & Printing-I (Code: WPE 341)
Time: 3.0 Hrs. Full Marks: 105
(Use separate answer script for Part: A and Part: B)
(All parts of a question must be answered consecutively)
Part: A
(Answer any three questions)
1. (a) Define dye stuff. Mention its main properties.
(b) Differentiate between dyes and pigments.
(c) Write steps of dyeing according to "Theory of Dyeing".
[5.5+6+6=17.5]
2. (a) Three direct dyes X, Y, Z are class A, B, C respectively. As a dyer which dyes you will prefer for continuous dyeing? State your argument for such preference.
(b) How can you improve the wash fastness of direct dye by after treatment with formaldehyde? Write down the chemical mechanism.
(c) Salt increases the exhaustion of anionic dye during dyeing with cellulosic fiber. How can you explain the exhaustion mechanism of salt for dyeing cellulosic fiber with anionic dye?
(d) Why basic dyes is so popular for jute dyeing.
[4+5.5+(2+2)+4=17.5]
3. (a) Graphically show and explain the effect of acids on exhaustion of Acid dyes.