Methods of Printing
Faculty incharge :
Mr. V. Sivalingam Chairperson –fashion & textiles NIFT, BANGALORE
RajshreeSoni B.F.TechV Roll No. 24 2008-12
Defects In Dyeing
Common causes of dyeing defects
• Materials not prepared properly • Poor machine conditions • Poor water quality • Short comings in dyeing solutions
1.Materials not prepared properly
• • • • • • • • Material having dead fibres or other defective fibres Left over of Chemicals after bleaching etc. Material not properly desized Material not properly mercerised. Absorbency of the fabric not proper Sticking of insoluble material on the fibres Impurities are not removed properly Uneven heat treatment.
2. Poor machine conditions
• Coming out of Dye liquor during dyeing • Defective instruments controlling temperature, pressure speed etc.
3. Poor water quality • • • • More Hardness of water Water has metal ions such as iron. PH of water not proper Water having more chlorine
4. Short comings in dyeing solutions
• Improper weight ratio of colors and chemicals. • Improper material to water ratio • Improper filtering of concentrated colors.
Common dyeing defects, their causes and remedies
• Deep selvedges: Due to difference in construction of fabric at selvedges (different weave) variation in dyeing is seen at selvedges.
• Perforation marks : In beam dyeing machine perforation marks are seen which are due to splashing of color.
Defects Deep selvedge
Weave at selvedges are Immediate action should generally stronger than be taken into account as the textile which affects the fabric is dyed the dye penetration.
In beam dyeing ,due to Uniform application of splashing of color. pressure and temperature can help in overcoming this type of defects.
• Color crocking
▫ Color in a dyed fabric which rubs off rather easily on to other fabric surface. ▫ Caused by inadequate scouring at the completion of the dyeing cycle.
• Streaks yarn: ▫ The thick yarn in dyed fabric visible as streaks after dyeing.
Defects Color crocking
Caused by inadequate Proper accumulation of scouring at the material:liquor ratio. completion of the dyeing cycle.
The thick yarn in dyed Fabric should have fabric visible as proper uniform warps and wefts. streaks after dyeing.
• Off Shade
• An expression referring to the fact that the color of the dyed fabric does not match the standard color or reference sample
•A shade change in a fabric that appears as a horizontal selvedge to selvedge change. •Caused by a filling change or loom stop and subsequent start up.
Defects Off shade
Caused by inadequate Proper accumulation completion of the of material:liquor dyeing cycle. ratio in different bath prepared for achieving same depth of color. Non uniform M:l ratio should be application of dye or maintained varying m:l ration in throughout dyeing. single bath w.r.t. time constraint
Stained Cross Bar
In cross dyed fabric , usually of one color and white ,where the dye of the colored portion stains the white portion some times called unclear cross dye. In solid color fabric, the term refers to specks of foreign fibre that have been caught in the material and do not become dyed.
•A discolored area on the cloth. •Caused by foreign matter such as dirt, grease, oil or residue of sizing on the fabric being dyed.
Defects Stained cross bar
Specks of foreign fibre Proper and clean that have been caught dyeing floor area in the material and do should be maintained not become dyed
Caused by foreign Dirt and dust should matter such as dirt, be taken into account grease, oil or residue at the time of dyeing. of sizing on the fabric being dyed
• Tender spot:
Places in the fabric that have been excessively...