Yaa Common Salt In Addition To Alkali Gratuitous Reactive Dyeing On Cotton Fiber Cloth (Part-1)

Salt too Alkali Free Reactive Dyeing on Cotton Fabric (Part-1)

Engineer Md Selim Hossain
Jr. IE Officer, Urmi Group
Contact: 01722972420 


Part-2

ABSTRACT
This projection is on ‘‘Salt too Alkali Free Reactive Dyeing on Cotton Fabric". This is a dyeing physical care for where cotton fiber stuff is dyed without tabular array salt too soda ash.

The experiment was conducted inward the Laboratory of DIU, Department of TE & lab dip of NTL. The aim of this projection is to dye the stuff without tabular array salt too alkali which volition live economic, non-toxic too easily physical care for able for the textile processing.

The role of tabular array salt too soda makes the effluent toxic for the environment. In conventional method of dyeing on cotton fiber amongst reactive dyes, alkali pH should live maintained inward dye bath. This method requires to a greater extent than electrolytes for exhaustion too alkali for fixation.

In this project, fiber alteration techniques based on polyacrylamide possess got discussed. Color fastness bear witness is done later on dyeing the cotton fiber fabric. It is to live hoped that past times the cease of this thesis newspaper the reader volition possess got a amend thought most “Salt too Alkali costless reactive dyeing on cotton fiber fabric”.

INTRODUCTION
In electrical current practice, cellulosic fibers are predominantly dyed amongst reactive dyes inward the presence of a considerable sum of tabular array salt too fixed nether alkali metal conditions. However, dye fixation efficiency on cellulosic fibers is by too large depression (varying from l – 90%). This, results inward a highly colored dye effluent, which is unfavorable on environmental grounds. Furthermore, the high concentrations (40 – 100g/I) of electrolyte too alkali (5 – xx g/I) required inward cellulose fiber dyeing may pose additional effluent problems.

In this work, a novel fiber – alteration technique based on cationic acrylic copolymer is used. Pretreatment of cellulosic fiber amongst Polymer is believed to offering an chance for increasing both the substantively too reactivity of fibers towards reactive dyes nether neutral conditions. The nature of a reactive polymer resin is such that it may react amongst nucleophilic sites inward cellulosic fibers or inward the polymer itself, thus fixing the polymer to the substrate. During subsequent dyeing, farther reactions betwixt the polymer too the dyestuff, the fiber too the dyestuff, too the fiber too the polymer too tin dismiss live expected to accept place, forming crosslink within the fibers.

Cotton fabric:
Cotton is a natural fiber that comes from the seedpod of the cotton fiber works life too is used to construct many stuff types at every toll point. The fiber is hollow inward the catch and, nether the microscope, resembles a twisted ribbon.

Fig: Cotton Fabric

Physical properties of cotton:
Physical properties of cotton fiber fibers are given below:

• Color: The color of cotton fiber fiber could live white, creamy white, blueish white, yellowish white or grey. 
• Tensile Strength: Cotton is moderately potent fiber. Tenacity of 3-5 gm/den. The wet forcefulness of cotton fiber is 20%
• Elongation at break: It has an elongation at interruption of 5-10%.
• Elastic Recovery: At 2% extension it has an ER of 74% too at 5% extension it has an ER of 45%.
• Specific Gravity: Specific gravity is 1.54.
• Moisture Regain (MR %): Standard wet find is 8.5.
• Effect of Heat: Cotton has an fantabulous resistance to degradation past times heat. It begins to plough yellowish later on several hours at 1200C too decomposes marked past times at 1500C. As a outcome of oxidation, cotton fiber is severally damaged later on few minutes at 2400C.
• Effect of Lord's Day Light: There is a gradual loss of forcefulness when cotton fiber is exposed to Sun calorie-free too the fiber plough yellow. By Sun calorie-free much of the harm is caused past times UV-light too past times the shorten weaves of visible light.
• Moisture Content (MC %): Standard wet content is 7.834.

Chemical Properties of Cotton:
Chemical properties of the cotton fiber fiber are given below:

• Effect of Acids: Cotton is attacked past times hot dilute acids or mutual frigidity concentrated acids which it disintegrates. It is non affected past times acids.
• Effects of Alkalis: Cotton has an fantabulous resistance to alkalis. It swells inward caustic alkalis ( NaOH) but it does non damaged. It tin dismiss live washed repeatedly inward lather solution without whatever problem.
• Effect of Organic Solvent: Cotton has high resistance to normal cleaning solvents. Cotton is dissolved past times the copper complexes, such every bit cuprammonium hydroxide, cupriethylene diamine too concentrated 70% H2SO4.
• Effects of Insects: Cotton is non attacked past times moth-grubs or beetles.
• Effect of Micro Organism: Cotton is attacked past times fungi too bacteria.

Reactive Dyes:
The reactive dyes are best for cotton fiber for its amend hit of application too amend fastness properties. Reactive dyes are mostly used inward the globe most 30%, because this dye is too then inexpensive too suitable for cotton fiber dyeing. It makes a covalent bond amongst the fiber polymer too deed every bit an integral business office of fiber.

In a reactive dye a chromophore contains a substituent that is activated too allowed to straight react to the surface of the substrate.

Popularity of Reactive Dye:
Reactive are mostly used for dyeing cellulosic fibers. At past times cellulosic fibers were dyed amongst take away too vat dyes, but later on the introduction of reactive dyes at that spot utility has teach limited. Reactive dyes are superior to take away dye inward the next aspects:

• Ability to physical care for brilliant shades of broad range.
• High leveling quality.
• Good washing fastness.
• Good calorie-free fastness.

And it is superior to vat dyes inward the next aspects:

• Simple dyeing method thus 1 stage dyeing.
• Low temperature dyeing (below 100°C)
• Lower cost, i.e. cheaper.

Again its dyeing physical care for is fast too gives brighter shades than metalized azo dyes. For the higher upward reasons reactive dyes are to a greater extent than popular.

Properties of reactive dye:

• Reactive dyes are anionic dyes which are used for dyeing cellulosic poly peptide polyamide fibers.
• Reactive dyes are works life inward powder, liquid too impress glue from.
• During dyeing, the reactive grouping of this dye forms covalent bond amongst fiber polymer too becomes an integral business office of fiber.
• Reactive dyes are soluble inward H2O & cheap.
• They possess got rattling practiced light, perspiration, launder & rubbing fastness amongst rating most 6.
• The dyes possess got rattling stable electron organization too the degrading outcome ultraviolet ray.

Structure of Reactive Dyes:

General construction of reactive dyes:

The full general construction of reactive dye is: D-B-G-X.

Chemical construction of reactive dyes:

Chemical construction of reactive dyes

Here,
D= dye business office or chromogen (color producing part)
Dyes may live direct, acid, disperse, premetallised dye etc.
B = bridging part.
Bridging business office may live –NH- grouping or –NR- group.
G = reactive grouping bearing part.
X= reactive group.

Classification of reactive dyes:
Reactive dyes may live classified inward diverse ways every bit below:

1) On the ground of reactive group:
a) Halogen (commonly chlorine) derivatives of nitrogen containing heterocycle, similar three types-

• Triazine grouping
• Pyridimine grouping
• Quinoxaline dyes   

Example:

Triazine derivatives: procion, cibacron.
Pyridimine derivatives: reactone
Quinoxaline derivatives: levafix. 

b) Activated vinyl compound:

• Vinyl sulphone
• Vinyl acrylamide
• Vinyl sulphonamide.

Example:
Vinyl sulphone: remazol
Vinyl acrylamide: primazine
Vinyl sulphonamide: levafix.

2) On the ground of reactivity:

• Lower reactive dye: Medium reactive dye: hither pH is maintained 11-12 past times using Na2CO3 inward dye bath.
• Higher reactive dye: hither pH is maintained 10-11 past times using NaHCO3 inward dye bath.

3) On the ground of dyeing temperature:

a) Cold brand:
These types of dyes comprise reactive grouping of high reactivity. So dyeing tin dismiss live done inward lower temperature i.e. 320-600C.  

For example: PROCION M, LIVAFIX E.

b) Medium brand:
This type of dyes contains reactive groups of moderate reactivity. So dyeing is done inward higher temperature than that of mutual frigidity construct dyes i.e. inward betwixt 600-710C temperatures.

For example, Remazol, Livafix are medium construct dyes.

c) Hot brand:
This type of dye contains reactive groups of to the lowest degree reactivity. So high temperature is required for dyeing i.e. 720-930 C temperature is required for dyeing.

For event PRICION H, CIBACRON are hot construct dyes.

Dyeing wheel too Important factors/phases inward Reactive Dyeing:

• pH of the substrate prior to dyeing
• pH of the dye lav
• Pretreatment of the substrate
• Solubility of the dyestuff
• Dyeing temperature
• Quality of H2O too tabular array salt
• Electrolyte concentration
• Dyeing fourth dimension
• Washing off sequence
• Type of alkali.

Functional grouping of reactive dyes:

Functions	Fixation	Temperature	Included inward Brands
Monochlorotriazine	Haloheterocycle	80°	Basilen E & PCibacron EProcion H,HE
Monofluorochlorotriazine	Haloheterocycle	40°	Cibacron F & C
Dichlorotriazine	Haloheterocycle	30°	Basilen MProcion MX
Difluorochloropyrimidine	Haloheterocycle	40°	Levafix EADrimarene K & R
Dichloroquinoxaline	Haloheterocycle	40°	Levafix E
Trichloropyrimidine	Haloheterocycle	80-98°	Drimarene X & ZCibacron T
Vinyl sulfone	activated double bond	40°	Remazol
Vinyl amide	activated double bond	40°	Remazol

Trade Names of Reactive Dye:

Some merchandise names of this dye are mentioned:

Trade name	Manufacturer	Country
Procion	I.C.I	U.K
Ciba cron	Ciba	Switzerland
Remazol	Hoechst	Germany
Levafix	Bayer	Germany
Reactone	Geigy	Switzerland
Primazin	BASF	Germany
Drimarine	Sandoz	Switzerland

Part-2 

Share this post