October 20, 2021
Dyeing is the process of adding color to textile product like fibers, yarns, and fabrics. Dyes are obtained from flowers, nuts, berries and other forms of vegetables and plants as well as from animal and mineral sources. These are known as natural dyes. The other class of dyes is known as synthetic dyes. These are based on a particular type of chemical composition.
In the process of dyeing, a slight carelessness or due to equipment and other reasons will cause dyeing failure. The following is the case of dyeing failure:
A. Uneven dyeing :
Improper color dosing, Improper soda and chemical dosing, Improper method of migration, Uneven pre-treatment,Uneven heat setting (synthetic fibers), Water hardness,Incorrect pH adjustment
Careful color dosing,Careful soda and other chemical dosing,Follow proper dye migration method,Ensure uniform,absorbency and whiteness,Identify water hardness and use sequestrant,Always measure pH of all processes
B . Dye spots/ colored spots :
1. Causes :
Dye deposition on the machine, Improper dissolving of dyes, Improper dissolving of alkali
2. Remedies :
Clean the machine properly with machine cleaner, Proper dissolving of dyes and chemicals, Passing dissolved dyes, through a mesh strainer (screen printing mesh fabric), so, that large un-dissolved aggregates are filtered and made smaller.
C . Patchy dyeing :
Faulty injection of alkali, Improper mixing and addition of color, Water hardness, Uneven heating in machine, Entanglement of fabric., Due to improper salt addition., Dye migration during intermediate dyeing, Uneven heat in the machine, etc.
Correct dosing of dyes and chemicals, Consistent heating in the machine, Check water hardness and add sequestrant,By ensuring proper pre-treatment.
D. Crease marks :
Poor opening of fabric rope in machine, Shock cooling of PES containing fabrics, Unequal pump/nozzle pressure and reel speed, High running speed of machine, Very high loading capacity, above that issued
Maintaining proper reel speed and pump pressure, Lower cooling rate, Reduce machine loading
E . Softener spots/ Chemical spots :
Due to excess foaming during softening, Excess softener dosage, Improper softener dosing, Large emulsion size of softener
Use no more than 2% o.w.f softener in machine, Proper softener dosing, Proper choice/ selection of softener, Use good quality anti-foaming agent if required
F . Soda spot & white spot :
Improper dosing of alkali, High alkalinity of bath, High water hardness
Proper and careful dosing of alkali, Check bath alkalinity
Measure water hardness and use good choice and quantity of sequestrant
G. Hole :
Improper mixing of caustic pellets during pre-treatment.
Properly dissolve caustic soda to avoid holes.
Due to friction of fabric against parts, Improper enzyme treatment, Poor yarn quality
Lubricate fabric, Air turning when required, Increase enzyme dosage, Increase passage of fabric through singeing machine, Use low-pilling yarns to make fabric
Today, GESTER analyzed several situations that will occur during the dyeing process.
With reference to GESTER's dyeing machine, Due to our company has more than 20 years of technology and experience in dyeing machine, and our salespersons will adopt a one-to-one model to improve and guarantee the after-sales service system.
Infrared Laboratory Dyeing Machine GT-D22
This Laboratory Dyeing Machine is oil bath type infrared laboratory dyeing machine, it combine the advantages of traditional glycerol dyeing machine with common infrared dyeing machine together. It’s apply to dyeing and testing the color fastness of the knitted fabric, woven fabric, yarn, cotton, loose fiber, zipper etc. It was special design for dyeing industry, chemical industry, raw material, cloth which can simulate the production conditions exactly and reach the process effect.