New Alkali Agents Of Reactive Dyeing And Its Application Properties

Reactive dyes because of the advantages of its good diffusivity, complete chromatography,good color fastness, gorgeous color, the relatively cheap price, and simple applicationprocess,and so on, and it can form covalent bonds with many fiber, therefore it has received thewidespread attention. On the traditional process, it is the use soda ash for fixation, because sodaash buffer action is stronger, and in a wider range of unit of concentration of aqueous solution ofpH changes in volatility is not big, and dyeing reproducibility, brightly colored dye cloth samples,but in the use process it have many shortcomings.1. The usage of soda ash is big, when dyeing the dark medium shade it usually use25%, bigmachinist’s labor strength, and high production cost.2.The water soluble of soda ash is poor, it is easy to agglomerate, and easy to cause thecylinder wall and bruises in the dyeing process, which cause defects such as cloth spots, color ofcolor flowers, especially the clour of emerald green and purple.3. Due to its strong buffer, and difficult cleaning after dyeing, water consumption is very big,and it would cause more waste water pollution, which increase the load of waste water treatmentcost.4. The dye bath contains calcium, magnesium and other metal ion affects the dyeing effect,and it can form scale deposition on the inner wall of the vats. Therefore, we need to develop the substitute alkali compound with an environmentallyfriendly and efficient, its performance with soda ash is in quite a performance at the same time,and soluble in cold water, simple melt, dispersed evenly in the dye solution, and it won’t producedyeing defect, less dosage, good buffer, good solid color effect, and the residual alkali washing toremove easily, which solve the current dye house reactive dye fixation of alkali agent problem.This paper in view of pure cotton knitted fabric reactive dyes dyeing problem of alkali agentwhich in the NingBo XiangShan Hengda Printing&Dyeing Co. Ltd., through the screening ofinitial alkali agent distribution method, we developed a new type alkali agent which can replacesoda ash for color fixation in reactive dying.First of all, we use the commercially available substitute alkali to the most fundamentalcolors red, yellow, blue and black solid color in Hengda Printing&Dyeing Co. Ltd., it was foundthat the commercial substitute alkali solid has good fixing effect to color yellow and blue when itcan be used instead of soda ash, but in the red and black solid color, fixation cannot improve thedye fixation rate and cotton in the depth of color even prolong the dying time, so indicating thesubstitution alkali is selective for reactive dyes.At the beginning,we set several kinds of inorganic alkali agent: such as NaOH, Na2CO3,K2CO3, NaHCO3, K3PO4·3H2O, anhydrous Na3PO4, anhydrous meta-Na2SiO3, etc, when measureits alkaline buffer respectively and survey dyeing curve of pure cotton knitted fabric, we foundNaOH and anhydrous meta-Na2SiO3alkaline water is very strong, and anhydrous meta-Na2SiO3has good alkaline buffer,, but due to its too alkaline,it cause hydrolysis reactive dye andlow fixation rate and color deep; Na2CO3、K2CO3、K3PO4·3H2O、anhydrous Na3PO4have acharacteristic of medium alkaline,but the buffer is strong.The color fastness is higher0.5-1degree when the cotton fixed with K3PO4·3H2O and anhydrous Na3PO4; and the dosage ofK3PO4·3H2O and anhydrous Na3PO4is less than half the Na2CO3、K2CO3.The advantage ofNaHCO3is too weak alkaline, not suitable for reactive dye fixation.In addition, in order to makebetter uniform on dye fixation reactive dye, we need to add a chelating ability of substances to getscattered distribution of material, such as EDTA.In the compound experiment, To the beginning is amplification experiment. First we chooseNaOH, anhydrous meta-Na2SiO3、K3PO4·3H2O as raw material to set up10compound scheme, it shows that the fixation rate reached up to72.69%when we use10%NaOH,40%anhydrousmeta-Na2SiO3,50%K3PO4·3H2O as the fixing agent. Then we choose NaOH, anhydrous meta-Na2SiO3、anhydrous Na3PO4as raw material to set up10compound scheme, it shows that thefixation rate reached up to73.16%when we do not use NaOH,50%anhydrous meta-Na2SiO3,50%anhydrousNa3PO4as the fixing agent, It shows that the join of the Na3PO4can obtain betterfixation rate than K3PO4.Next we choose NaOH, anhydrous meta-Na2SiO3、soda ash as raw material to set up10compound scheme, it shows that the fixation rate reached up to68.77%when we do not useNaOH,50%anhydrous meta-Na2SiO3,50%soda as the fixing agent,Then we choose NaOH,anhydrous meta-Na2SiO3,K3PO4·3H2O as raw material to set up10compound scheme, it showsthat the fixation rate reached up to66.40%when we use10%NaOH,40%anhydrousmeta-Na2SiO3,50%K2CO3as the fixing agent, it explains that the addition of Na2CO3and K2CO3can not increase the fixation rate, at the same time, the addition of NaOH will also reduce thefixation rate.So we firstly set the self-making substitution alkali with NaOH,anhydrousmeta-Na2SiO3,K3PO4·3H2O, anhydrous Na3PO4.In the process of the further reducing compound experiment,We found the conclusion thatBH-3BS red has the best fixation with the alkali agent which mixed proportion of12%NaOH,35%anhydrous meta-Na2SiO3,15%K3PO4·3H2O and35%anhydrous Na3PO4.It is better than sodaash.When dying28s pure cotton knitted fabric, the dosage amounts of BH-3BS red is4%(o.w.f),the dosage amounts of sodium sulphate is70%(o.w.f), the dosage amounts of soda ash is25%(o.w.f),60℃fixation of40min,it reaches the fixation rate of71.22%, in the same condition thedelisting,The commercially available alternative alkali of GuoGuang brand3%(o.w.f), thefixation rate is62.52%. The commercially available alternative alkali of ShenEn brand3%(o.w.f),the fixation rate is62.85%, and3%(o.w.f) compound substitution alkali,the fixation ratecan reach72.71%. In the same condition, For26s pure cotton knitted fabric, the fixation rate ofsoda ash is71.71%, The commercially available alternative alkali of GuoGuang brand is66.28%,The commercially available alternative alkali of ShenEn brand is69.62%,and the compundsubstitution alkali is72.92%. In addition, It has reached better spell color dyeing effect more thansoda ash, and it shows that the mixed alternative alkali had made up for the inadequacy of commercially available substitution alkali. In subsequent experiments, the fixation rate wouldreduce when we add the content of Na2CO3or K2CO3to the best proportion,so the final mainmaterial formula is12%NaOH,38%anhydrous meta-Na2SiO3,15%K3PO43·H2O,35%anhydrous Na3PO4and some EDTA, and we named the recipe as ZP.Optimize the substitution alkali solution, it is concluded that when dying4%(o.w.f), thebest dosage of the substitution alkali dosage is3%(o.w.f), and when dying2%(o.w.f), the bestdosage of the substitution alkali is2.5%(o.w.f). After the fixation with this substitution alkali, thefibre has more better washing fastness, wet rubbing fastness than soda ash, at the end of thedyeing, it can save a washing, and reducing the price of alkali.