Important Viva Questions of Textile Dyeing || 200 Most Important Textile Coloration Interview Questions

In this article we will discuss 200 important short/viva questions of Textile Dyeing/Coloration, which will be very helpful for textile students, graduates, job seekers and industry professionals.

Note: Important Short/Viva Questions;

1. Differentiate between dye exhaustion and diffusion./Define Dye Exhaustion. /Define Dye Diffusion.
2. What do you mean by colouration? / What do you mean by dying?
3. Define Concentration gradient.
4. Differentiate between affinity and substantivity of dyes? 
5. Define Dye Affinity.
6. Define Dye Substantivity.
7. Define dyestuff.
8. What are the general classes of dyes? / Enlist different types of dyes.
9. What do you mean by pre-treatment? / What is the purpose of fabric pretreatment in textile dyeing?
10. Define polyester cotton (PC) Blend fabric?
11. Define blended fabric.
12. Enlist the steps involved in the pre-treatment of polyester cotton blend.
13. Define pretreatment of polyester and polyester cotton blend.
14. What are the types of dyes used for polyester fabric? Also, give a reason. / Why disperse dyes are more suitable for dyeing polyester fibre? 
15. Which types of fibres the disperse dyes are applied?
16. Define polyester-cotton (PC) bleaching.
17. Define polyester bleaching. / State bleaching of polyester.
18. Which types of chemicals are used in scouring polyester fabric?
19. Briefly describe the scouring and bleaching of polyester fabric.
20. Describe caustisization of polyester fabric.
21. In which condition the bleaching is not necessary?
22. Differentiate between conduction, convection and IR heating mechanisms. / What are the three heating mechanisms?
23. Define polyester fibres. /What are the raw materials of polyester fabric?
24. What is the main objective of heat setting in polyester fabric?
25. How the heat setting of polyester fabric is carried out?
26. Which type of singeing position is used in polyester fabric?
27. What do you mean by washing?
28. Define cleaning.
29. Define disperse dyes. / What are the basic mechanisms of disperse dyeing on polyester fabric?
30. Define color fastness. 
31. What the colour fastness properties are of disperse dyes?
32. Define carriers.
33. What is the function of carriers in disperse dyeing?
34. Write the commercial names of carriers.
35. Write dyeing on a jigger with the carrier.
36. What is the purpose of reduction clearing in disperse dyeing of polyester fibre?
37. What is the recipe for reduction clearing process of disperse dyeing?
38. Define continuous dyeing.
39. Define semi-continuous dyeing.
40. What is the function of the dispersing agent in disperse dyeing? 
41. Define dispersing of disperse dyes.
42. What is the function of leveling agent in the dyeing process?
43. Describe the dyeing profile of the HT dyeing process of polyester fabric with disperse dyes?
44. How much temperature is used in HT Dyeing process of polyester fabric?
45. Which types of dyeing machines are used in HT dyeing process of polyester fabric?
46. What is the Thermosol process?
47. What is the sequence of thermosol dyeing process of polyester fabric with disperse dye?
48. What is the padding process? / State the advantages of padding process.
49. Describe intermediate drying of thermosol dyeing process./what is intermediate dyeing?
50. Write the benefits of thermosol treatments.
51. How the disperse dyes are fix on polyester fabric? / Briefly describe the fixation of disperse dyes on polyester fabric.
52. What is the recipe of padding trough of disperse dyeing of polyester fabric?
53. Briefly describe the sublimation property of disperse dyes.
54. How does a grey fabric differ from a finished fabric?
55. How the dyeing of polyester fabric is carried by discontinuous methods?
56. Write about the dyeing of polyester cellulosic blend by discontinuous method?
57. What are the advantages of continuous and exhaust dyeing process?
58. Write about the dyeing of polyester-cotton blends by continuous method.
59. Introduction of denim dyeing/what is denim dyeing?
60. Briefly describe the slasher dyeing process of denim? / State the method of slasher dyeing.
61. Briefly describe the indigo rope dyeing process of denim fabric? / What is indigo rope dyeing?
62. Why rope dyeing is carried out.
63. Describe denim fabric. / define denim fabric.
64. Enlist the names of different denim finish processes. / Define denim finishing.
65. Define cone dyeing.
66. Define yarn dyeing.
67. Define knitted fabric. / What do you understand by hosiery fabrics?
68. State pretreatment of hosiery dyeing.
69. Define calendaring of hosiery fabric.
70. State the one-bath direct dyeing.
71. Write dyeing of hosiery fabric with reactive dye.
72. Define the winch dyeing process.
73. Which types of dyeing machines are used for dyeing of knitted fabric?
74. How the desizing of knitted fabric is carried out?
75. Define the scouring process.
76. Define desizing process.
77. What is sublimation? / What is sublimation of dyes?
78. What is de-oiling of knitted fabric? 
79. What is the function of soda ash in reactive dyeing?
80. Why reactive dyes are called reactive?
81. What do you mean by finishing? / Define fabric finishing.
82. Define printing.
83. Define reactive dyes.
84. What are mordant dyes? / Define mordant dyes.
85. What do you mean by natural mordant dyes?
86. State acid mordant dyes. 
87. Briefly describe the mordanting process of acid dyes?
88. Define chrome dyes?
89. Enlist the general properties of chrome dyes.
90. What are metal-containing dyes?
91. State the uses of chrome dyes.
92. State the uses of acid-mordant dyes.
93. Why the mordanting is carried out in acid dyes?
94. What are the advantages of the mordanting process of acid wool dyes?
95. Differentiate between the pre-mordanting and after-mordanting process of acid wool dyes?
96. What are the advantages and disadvantages of the pre-mordanting process of acid wool dyes?
97. What are the major problems with chrome dyes?
98. Enlist the names of mordants that are used in the acid dyeing process.
99. What is the effect of the mordanting process on the colour matching of acid wool dyes?
100. Briefly describe azoic dye? /define azoic dye. / Define azoic colors.
101. State the use of azoic dye.
102. What are the two main components used for the manufacturing of azoic dyes?
103. What is the importance of electrolyte (salt) in azoic dyes?
104. What do you mean by electrolytes?
105. Define azoic dyeing by exhaust method.
106. What are the types of azoic dyes according to their substantivity?
107. Briefly describe the naphtholation process of azoic dye. / What is naphtholation?
108. Define diazotization process of azoic dye.
109. How many reactions in azo dyeing?
110. What is development in azo dye?
111. What are the methods of dissolution of naphthol? / What is the dissolution of naphthol? / What is the cold dissolution of naphthol? / What is HOT dissolution of naphthol?
112. Briefly describe the stripping process of azoic dyes. / How do azo dyes strip?
113. Define tailing fault. / What do you understand from the tailing effect? / What do you mean by the tailing problem of a continuous dyeing machine?
114. Briefly describe the classification of vat dyes.
115. How the vat dyes are solubilized in water?
116. State the properties of solubilized vat dyes.
117. State the classification of solubilized vat dyes.
118. What is the vatting process?
119. Why is oxidation of VAT required?
120. How the original colours are developed in the vat dyeing process.
121. Define VAT dyes.
122. Enlist properties of vat dyes.
123. What do you mean by solubility?
124. State the classification of vat dyes.
125. What are acid dyes? / define acid dye.
126. Define wool dyeing.
127. Define cellulosic fibers.
128. Define protein fibers.
129. Define acid dye solution.
130. Enlist the benefits of wool dyeing with acid dyes.
131. Enlist the general properties of wool.
132. What is the basic difference between direct and acid dyes?
133. Give a brief introduction of acid dyes.
134. What are protein fibres?
135. Define the amphoteric nature of the wool fibre.
136. Enlist the classification of acid dye according to dyeing characteristics?
137. Differentiate between levelling and super milling acid dyes.
138. What is the effect of salt in wool dyeing with level acid dyes?
139. What is the effect of molecular size of level acid dyes on water-soluble properties?
140. Make a dyeing profile of level acid dyes.
141. What is the effect of pH in wool dyeing with level acid dyes and milling dyes?
142. What is the effect of dye substantivity in wool dyeing with level acid dyes and milling dyes?
143. Compare the fastness properties of level acid dyes and milling dyes.
144. Why Glauber’s salt is used in wool dyeing with super milling dyes?
145. Briefly describe the stripping process of acid wool dyes.
146. What is the effect of damaged wool fibre on level dyeing?
147. Describe the chlorination process of wool fiber.
148. State the mechanism of wool dyeing.
149. Define cellulosic fibre test.
150. Define polyester fibre test.
151. Write the description of dyeing faults.
152. Write suggested repair of dyeing faults.
153. What do you understand from tendering?
154. How do you identify that material is cotton?
155. Which chemical is used to identify wool?
156. What is the use of metacresol in the processing lab?
157. Describe the L-C-R Dyeing problem.
158. What do you mean by testing of dyestuff?
159. Define acrylic fibres.
160. Define processing.
161. Enlist common faults during processing.
162. What do you mean by skittery dyeing?
163. Describe the tailing dyeing problem in the continuous dyeing process.
164. Define dye hydrolysis in reactive dyes.
165. What is the effect of heavy metal ions in a dyeing bath or reactive dye?
166. What do you mean by the tailing problem of the continuous dyeing process?
167. Describe the L-C-R dyeing problem.
168. Define the tendering problem of the sulphur dyeing process.
169. What are the possible causes of bronziness in the sulphur dyeing process?
170. What are the types of machines used for yarn dyeing?
171. Differentiate between the winch and jigger dyeing machines.
172. Briefly describe the function of the jet dyeing machine.
173. What are the applications of winch and jigger dyeing machines?
174. What are the names of exhaust and continuous dyeing machines?
175. Enlist the machines for dyeing.
176. Define loose stock dyeing machine.
177. What is Hank dyeing?
178. What is a winch?
179. State the close and open winch dyeing machine.
180. What is the difference between closed and open jigger?
181. What is the use of a pressure jigger?
182. State the advantages of the beam dyeing machine.
183. State the advantages of padding.
184. State the advantages of a jet dyeing machine.
185. What do you understand from padding?
186. What is the use of padder in dyeing mills?
187. Briefly describe the function of the jet dyeing machine.
188. What is the application of a winch dyeing machine?
189. What is the advantage and disadvantages of a jigger dyeing machine?
190. State the advantages of the beam dyeing machine.
191. What is the use of a pressure jigger dyeing machine?
192. Define the colour fastness property of dye.
193. Define yarn dyeing.
194. Define fabric dyeing.
195. Define beam dyeing.
196. What is piece dyeing?
197. What is the function of electrolyte in dyeing?
198. Name any two electrolytes used in dyeing.
199. Define jigger dyeing.
200. Define padder dyeing.

NOTE: Long Questions:

 Q.1: Describe the dyeing of polyester by exhaust method (High-Temperature dyeing). 

Q.2: What is the effect of the carrier on the colour yield of dispersed dye. What different theories are established for carrier working? / Explain the method of polyester dyeing with the carrier.

Q.3: Describe the Thermosol dyeing process of polyester fabric.

Q.4: What are the types of methods used for yarn dyeing of denim fabric? 

Q.5: What are the methods of application of acid-mordant dyes?

Q.6: What is the method of dissolution of naphthol?

Q.7: What are the basic reactions of azoic dye?

Q.8: Briefly explain the classification of vat dyes. 

Q.9: Write a note on the exhaust dyeing process of cotton with azoic dyes. / Explain the dyeing procedure with azoic colours and write about fastness properties.

Q.10: Write a comprehensive note on the mechanism of wool dyeing with acid dyes.    

Q.11: Write a comprehensive note on level acid dye and milling acid dye.

Q.12: what tests are used to identify dyes applied on cellulosic fabric.

Q.13: Differentiate the working principle of the following dyeing machines.

• Jigger Dyeing Machine
• Winch Machine

Q.14: Differentiate the pretreatment of polyester and P/C blend with 100% cotton fabric.

Q.15: write the advantages of dyeing polyester and P/C blend by discontinuous method.

Q.16: Compare the dyeing of polyester and P/C blends by continuous with the semi-continuous method.

Q.17: write a comprehensive note about denim finishing fabric.

Q.18: write the difficulties facing the processing of hosiery fabrics and how we overcome them?

Q.19: Draw a neat sketch of machines for dyeing and label the parts.

• Beam Dyeing Machine
• Jet dyeing Machine

Q.20: Explain the dyeing of wool with acid dyes and also write about fastness properties.

Q.21: State the methods of identification of dyestuff on dyes and printed fabric.

Q.22: Write the reasons and methods of repairing the common faults during processing.

Q.23: Write a note on polyester bleaching. 

Q.24: Explain the dyeing method of indigo.

Q.25: Explain the dyeing method with reactive dyes for hosiery.

Q.26: Explain the working of the thermosol machine.

Q.27: Write down the complete method of wool dyeing with acid acids.

Q.28: Brief note on the dissolving method of vat dyes.

Q.29: Write the method to identify a class of dye used in cotton-dyed fabric.

Q.30: Write down the general problems of dyeing and reason.

Q.31: Write a note on the working of the winch dyeing machine.

Q.32: Write a note on fabric dyeing.

Q.33: Write a note on common faults produced during processing.

Q.34: Write a note on wool dyeing with acid dye. 

Q.35: write a note on the following;

• Padding Process
• Jigger dyeing Machine

Q.36: Write a comprehensive note on the pretreatment and dying process of hosiery fabrics.

Q.37: What tests are used to identify acid dyes applied on protein fibre.

Q.38: Write the method of dyeing with sulfur dye. 

Q.39: Write the difference between woven fabric dyeing with knitted fabric dyeing.

Q.40: Write a detailed note on reactive dyes. 

Q.41: Write a note on two bath dyeing of fabric.

Q.42: Write a note on the pretreatment of fabric.

Author:

Engr. Muhammad Usman Ashraf

HOD Textile Department at TEVTA Punjab, Pakistan.

M.Sc Textile Engineering (NTU, Faisalabad)

Email: usmanashraf884@gmail.com