Textile Notes related to fiber, yarn, fabric knowledge, spinning, weaving, processing, projects, knitting, Indian Traditional Textiles and denim manufacturing
Khadi is a handspun and handwoven fabric. The following issues often come up when buying this fabric:
1. It is difficult to source these yarns. As these yarns are concentrated in the unorganized sector with regard to their production and the process is immensely labor oriented.
2. Handspun yarn is of two varieties. One variety is called the original Charkha variety in which the raw cotton is drawn and twisted by hand on a charkha and wound. This quality is most difficult to find and bulk production is not possible. This is most suited for coarse counts suitable for hand spinning. The other quality is called the Amber quality, in which the yarn is twisted by hand by a process called Amber Charkha in which the input material is roving from mills. Moreover the final twisting and drawing operation is done by ring and traveler arrangement. The only difference from ring frame is that this ring and traveler is rotated with the help of a handle. Here bulk production is possible, finer counts are also possible and most of the handspun yarn is made using this process. There is this fabric called “Malkha” where the pre spinning part is done using a small scale machine developed by Vortex, however the yarn is Z twisted, as that of a milspun yarn.
3. Khadi yarn in a fabric is determined by the amount and frequency of slubs that are coming in the fabric as well as twist. The twist in a khadi yarn is by convention opposite to that found in a milspun yarn. However, this reverse twisted yarn is also now being made in mills, though surreptitiously. I myself have seen a cone of a kahdi yarn made of machine in a mill.
4. The quality of khadi yarn is not so good so as to be used in warp. The cotton used to make these yarns is of short staple quality and often quite old. It is therefore, used in weft, using handspun yarns. Attempts to get the quantities in production for handspun yarns have resulted in inordinate delays in the deliveries and numerous fabric defects.
5. The count of khadi varies sometimes as much as 10-15%, this makes it difficult to keep the GSM of the khadi consistent.
6. Khadi yarn doesn’t lend itself to be machine dyed on a continuous range. It can be cabinet dyed but the cabinets have to be modified as the diameter of lea of khadi is less than that of a normal hank yarn. Usually it is dyed by hand using vat dyes. As the cotton comes from various sources- sometimes recycled cotton is used- it might give specks in the form of foreign fibers.
7. When woven in yarn dyed form, it might give bandings as the yarn spools can be from two different sources. To avoid that, on a powerloom, Khadi is made using two shuttles.
8. Khadi white is done by bleaching the yarn using homemade furnaces. This might give yellowness to the overall fabric, which is such a characteristic color for the original khadi. However, in order to cater to the requirement of buyers who still think in an export way, it is bleached in the fabric form. However, that reduces the weight of the khadi and makes it much thinner.
9. As it is also a handloom fabrics, getting bulk production and timely deliveries are always an issue.
Every traditional fabric has Its own list of defects, some
defects are inherent to the techniques, one has to live with them if they want
that fabric.
All fabric indigo dyed or printed traditionally rub or
bleed. It applies to Dabu and Bagru styles of printing. The dyeing is done in
indigo pits, the concentration of which is kept in check by adding lime or
Jaggery. Also every thaan has different shade of color in it. Traditionally
these are dried in the sun and weather condition affects them. Indigo fabrics also
fade, this poses a problem in storing them in stores where they can develop
prominent fold marks. Kalamkari is also better in this respect except the
designs which contains blue color which tends to rub or bleed. Ajraks are
better in this respect. The fact that these fabrics are washed many times
before the final process, make them much better as far as colorfastness to
washing, rubbing or light is concerned. Dhars have very good colorfastness to
washing or rubbing. Pigment prints are better in these respect, only difference
is made when they are printed on traditionally handwoven fabric such as
Managalgiris, where the base color often bleeds.
Ikats especially containing more than three colors are prone
to bleeding as direct or napthol colors are used. Reactive dyes cannot be used
as in the high temperature process of reactive dyes, the dyes will penetrate
inside the rubber band used to tie the yarn. However it is possible to dye with
reactive dyes warp ikats used in Andhra if the number of colors are less than
three. In Orissa where weft Ikat is used, only direct or napthol colors are
permitted, getting the colorfastness is a challenge.
For normal powerloom cotton fabrics woven in UP and Bihar,
the yarn dyeing is often done with vat colors. However for black, sulphur black
is used. It has a danger as the yarn becomes tender if the fabric is not washed
properly after weaving. It leads to tearing of the fabric. Tearing is also
observed in Patri print of Jaipur done with Aniline Black dyes, if the fabric
is stored for longer time.Luckily, most of the weavers are shifting to the
chamber dyeing, where the yarn hanks are dyed with reactive dyes and a
colorfastness of the range of 4-5 is obtainable.
Silks from Varanasi has no problems whatsoever with
drycleaning. However Silk when blended with viscose problems poses a problem
with colorfastness when piece dyed. The people in Patna, Bhagalpur and Purnia
still are using direct dyes which make the fabric vulnerable to the
colorfastness. Silk Matkas, Mugas and Ghicha do not pose any problems.
Traditional fabrics of south are dyed with reactive dyes so
colorfastness is not a problem there.
Width affects consumption. This is very important in case of
ethnic fabrics as most of them come at a width which is either lower or higher
than the one contracted. As the fabric is dyed using local methods and dried in
the air, it is impossible to control width or variations of widths over length.
We’ll take some cases of the fabric.
When working with block prints on cotton, the fabric is
usually mill and often powerloom. It is prepared locally at the printer’s for
printing. Sometimes width contraction happens to full 10 inches. This happens
specially in case of voile with lower constructions (92 x 80). It is useful to
calculate the consumption under various width and issue out the fabrics based
on that.
Width problem also occur in prints on powerloom cambric,
mull or Mangalgiri. Due to different shrinkage treatment at the processing
stage after weaving, sometimes after washing width reduces to an unequal
amount.
Greige fabric, if dyed in dark colors is subject to full
mercerization, shrinks the fabric widthwise, sometimes to a considerable extent.
Weft Ikat has a special problem with regard to width, the
cuttable width is about 2 inches less than the actual width. Because of
problems with tyeing the weft yarn, the actual Ikat motif start one inches
inside the actual width.
The best way to control is to take the min. width of the
whole lot and work out consumption based on that width. Or different thaans can
be issued out at different consumptions.
Lots of pintucks are woven widthwise, which means that stripes come in the weftwise direction. To make them suitable for mens or women's garments bigger widths are chosen on loom. Similarly in heavy silk fabrics, bigger widths are chosen as the stripes run in the weft.
Woollen shawls and stole present a particular problem as the best of the stripes come in weftwise direction.
Width poses no problems when working with silks or woolens.
Factors to Consider While Buying Indian Traditional Fabrics: Thaan Length and Fabric Wastage
Indian traditional fabrics are rarely bought like standard mill-made fabrics. A merchandiser may assume that fabric will come in continuous rolls of 20, 30, 50 or 100 metres, but many traditional fabrics come in short folded lengths known as थान / thaan. This simple difference can seriously affect consumption, cutting efficiency, garment costing, jobwork planning and final wastage.
A thaan is a traditional fabric length. In Hindi, थान generally refers to a fabric piece or fabric bundle. In the context of Indian traditional textiles, it is better to think of it as a folded bolt or piece length, not always as a machine-wound roll. The important point is that thaan length is not a small technical detail; it directly affects fabric consumption and wastage.
When fabric is issued for garment conversion, the cutting room needs usable continuous length. If the thaan length is short, every thaan creates its own end loss. A 50-metre roll may have only two ends, but ten pieces of 5 metres each will have twenty ends. Every end creates a possibility of wastage.
This wastage may come from unusable end pieces, cutting allowance, mismatch between garment marker length and thaan length, print placement limitations, shrinkage allowance, defects at the beginning or end of the thaan, and inability to combine small leftover pieces across sizes.
Therefore, while calculating fabric consumption, the buyer should not ask only: “What is the average consumption per garment?” The better question is: “What is the average consumption per garment after considering actual thaan length?”
This distinction becomes especially important in Indian traditional fabrics because their production processes often restrict the maximum fabric length that can be made, handled, dyed, printed, dried or woven.
Visual 1: How short thaan lengths create end losses during garment cutting.
The Kota Fabric Example
A useful example is Kota fabric from Rajasthan. Kota fabric was selected for conversion into garments and was to be used as an outer fabric over a cambric printed base. Traditionally, the fabric came in 10.5 metre lengths, which roughly corresponded to two saree lengths. However, this fact was ignored during ordering and consumption calculation. When the fabric arrived, the wastage increased by almost 10% of the total ordered length.
This is a classic merchandiser’s mistake. On paper, the garment consumption may look correct. But once the fabric reaches the cutting table, the cutting master discovers that the marker does not fit neatly into the available thaan length. The leftover may be too small for another garment, and the loss becomes real.
For example, suppose one garment requires 2.8 metres of Kota as an outer layer. A 10.5 metre thaan theoretically gives:
\[
\frac{10.5}{2.8} = 3.75
\]
This means only 3 garments can be cut comfortably from one thaan, leaving:
\[
10.5 - (3 \times 2.8) = 2.1 \text{ metres}
\]
That 2.1 metres may not be enough for another garment. It may be usable for trims, yokes, kidswear, patch panels or accessories, but if there is no such planning, it becomes wastage.
Merchandising lesson: The problem is not the fabric. The problem is that the traditional fabric length was not integrated into the garment consumption calculation.
Traditional Printing and Short Thaan Lengths
Traditional Jaipur and Jodhpur prints, especially fabrics produced using techniques such as Dabu, Bagru and Ajrakh, often come in shorter lengths of around 5 to 6.5 metres. One practical reason is that these fabrics are manually dipped into dye baths and become heavy when wet. Longer lengths become difficult to handle, lift and dry manually.
This is an important point because it connects design, craft and production practicality. A buyer sitting in an office may expect longer lengths, but the artisan’s process may not allow it. If a 20-metre length cannot be physically dipped, carried, squeezed, dried or spread, then demanding such a length is not realistic.
In such cases, costing must respect the craft process. The buyer should ask what the usual thaan length is, what the maximum manageable length is, whether the length is fixed or variable, whether the length changes after washing or finishing, and whether defects are more common at the ends.
Traditional fabric buying requires production empathy. Without understanding the making process, consumption calculation becomes artificial.
Ikat and Thaan Length Limitations
Ikat fabrics from Odisha and Andhra Pradesh also have limitations in thaan length. This limitation is understandable because Ikat involves resist-dyeing of yarns before weaving. The design is created not by printing on the fabric surface, but by carefully dyeing yarn sections before they are woven.
If the design repeat, yarn preparation and loom setup are planned for a certain length, the resulting fabric length cannot always be stretched endlessly like a standard mill fabric. In Ikat, the buyer must understand whether the fabric is single Ikat or double Ikat, whether the design is continuous or placement-based, whether borders are present, and whether the visual rhythm will be disturbed during cutting.
For garment conversion, Ikat should not be treated as a plain dyed fabric. The pattern itself may decide the usable length.
Visual 2: Why traditional printing, Ikat preparation and handloom weaving often restrict fabric length.
Placement Prints and Exact Length Planning
Placement prints need even greater care. Lengths must be calculated carefully so that they become an exact multiple of the number of garments. This needs to be communicated to the printer size-wise. Normally, a small cutting gap is kept between printed garment lengths to facilitate clean separation during cutting.
In placement printing, the fabric is not just a surface. It is already carrying garment logic. The neckline, border, motif, hem, panel or yoke may be printed at a specific position. If the print repeat does not align with the garment length, wastage increases sharply.
For example, suppose a kurta requires 2.25 metres including cutting allowance. If a 6-metre printed thaan is supplied, then:
\[
6 - (2 \times 2.25) = 1.5 \text{ metres}
\]
The remaining 1.5 metres may not carry the correct placement print for another garment. So the theoretical fabric balance is not useful. In placement prints, leftover fabric is not always convertible into another garment because the print position may be wrong.
Therefore, the merchandiser must communicate size-wise garment length, front and back panel requirements, sleeve requirement, border direction, motif position, cutting gap, shrinkage allowance, matching allowance and left-right symmetry requirement.
Practical rule: A placement print order should never be raised only in metres. It should be raised with garment-wise layout logic.
Benaras Brocades, Chanderi and Mangalgiri Handlooms
When ordering Benaras brocades, the maximum thaan length may be limited because the weight on the cloth beam increases after weaving. Similar issues may arise in Chanderi and Mangalgiri handloom fabrics. This is another important learning: in handloom and brocade weaving, length is restricted not only by yarn or design but also by the loom and the weaver’s handling capacity.
A brocade fabric is heavier than a plain fabric because of extra figuring yarns, zari, supplementary weft or complex structures. As fabric accumulates on the cloth beam, the beam becomes heavier and bulkier. At some point, practical handling becomes difficult.
For handloom fabrics, buyers should ask what the normal loom length is, what the maximum comfortable thaan length is, whether beam weight affects weaving quality, whether longer lengths are likely to have more defects, and whether the fabric is being woven as saree length, dress material length or continuous garment fabric.
When the buyer understands these limitations, planning becomes more realistic and respectful.
A Simple Way to Calculate Thaan-Based Wastage
A merchandiser can use a simple calculation before placing an order. Let:
\[
L = \text{thaan length}
\]
\[
C = \text{fabric consumption per garment}
\]
\[
N = \left\lfloor \frac{L}{C} \right\rfloor
\]
Here, \(N\) is the number of full garments possible from one thaan. The leftover per thaan is:
\[
W = L - (N \times C)
\]
If 100 thaans are ordered, total leftover becomes:
\[
100 \times W
\]
This leftover may not be complete wastage if it can be used for smaller sizes, trims, contrast panels, kidswear, accessories or sampling. But if no such use is planned, it should be treated as practical wastage.
Example
Suppose thaan length is 10.5 metres and garment consumption is 2.6 metres.
\[
N = \left\lfloor \frac{10.5}{2.6} \right\rfloor = 4
\]
Fabric used:
\[
4 \times 2.6 = 10.4 \text{ metres}
\]
Leftover:
\[
10.5 - 10.4 = 0.1 \text{ metre}
\]
This is efficient. But if garment consumption is 2.8 metres:
\[
N = \left\lfloor \frac{10.5}{2.8} \right\rfloor = 3
\]
Fabric used:
\[
3 \times 2.8 = 8.4 \text{ metres}
\]
Leftover:
\[
10.5 - 8.4 = 2.1 \text{ metres}
\]
Now the wastage is much higher. This is why thaan length must be checked before finalizing the garment design, not after fabric arrival.
Visual 3: Simple calculation of garments per thaan and leftover fabric.
Buying Checklist for Traditional Fabric Thaan Length
Buying Question
Why It Matters
What is the actual thaan length?
Traditional fabrics may not come in standard mill roll lengths. Actual length must be confirmed before costing.
Is the length before or after processing?
Washing, dyeing, finishing and shrinkage can reduce usable length.
Does garment consumption divide neatly into the thaan length?
If not, end losses may become significant across the full order quantity.
Does the fabric have placement print, border or motif direction?
Directional designs reduce cutting flexibility and can increase wastage.
Can leftovers be used somewhere else?
Planning leftover usage in trims, yokes, potlis or kidswear can reduce effective wastage.
Before placing an order for Indian traditional fabric, the buyer or merchandiser should prepare a thaan-length checklist. Do not assume standard roll length. Ask for minimum, maximum and average thaan length. Traditional fabrics may not come in uniform lengths.
Also check whether the fabric length being quoted is before processing or after processing. A fabric may be woven at one length, printed at another usable length and finished at a slightly shorter length due to shrinkage. This difference can disturb the final order quantity if not accounted for.
The buyer should also match thaan length with garment consumption. If the thaan length is not an exact or near-exact multiple of garment consumption, calculate wastage before placing the order. Size-wise consumption should also be checked because a size S garment and an XXL garment may not consume the same fabric.
Common Mistakes While Buying Traditional Fabrics
One common mistake is to calculate consumption from a sample cutting and then multiply it by order quantity without checking thaan length. This works only when fabric comes in long continuous lengths. It does not always work for traditional fabrics supplied in shorter thaans.
Another mistake is to ignore end wastage. If every thaan is short, end wastage accumulates rapidly. A loss that appears small in one thaan becomes commercially significant when multiplied across hundreds or thousands of metres.
A third mistake is to treat saree-length fabric as garment fabric. Many traditional fabrics are produced in lengths suitable for sarees, dupattas or dress materials. Garment conversion requires a different logic. The buyer must check whether the existing fabric format supports the intended garment style.
A fourth mistake is not communicating size ratios to the fabric supplier. For placement prints, if the printer prints one standard length but the garment has multiple sizes, wastage or visual imbalance can occur.
A fifth mistake is not planning leftover usage. If leftover fabric is expected, then it should be designed into the product range from the beginning. Otherwise, the leftover becomes dead stock or hidden wastage.
Conclusion
Thaan length is one of the most overlooked factors in buying Indian traditional fabrics. It looks like a small operational detail, but it can affect the entire costing of a garment order. Short thaan lengths increase end wastage, reduce cutting efficiency and complicate placement planning.
The buyer must therefore check thaan length before confirming the design, consumption, costing and order quantity. In traditional textiles, fabric buying is not just procurement. It is a dialogue between design, craft, production, costing and cutting-room practicality.
A good merchandiser does not merely ask, “What is the rate per metre?” A good merchandiser asks, “In what length does this fabric actually come, and how will that length behave on the cutting table?”
Related Reading on Traditional Fabrics, Weaving and Garment Planning
This article is intended for educational and practical merchandising understanding. Actual thaan length, wastage, shrinkage, cutting efficiency and production feasibility may vary depending on fabric type, supplier, loom setup, printing process, finishing route, garment style, size ratio and cutting-room practice. Buyers and merchandisers should verify all technical and commercial assumptions with their suppliers, production teams and sampling departments before final order confirmation.
सूती धागों की तैयारी, ब्लीचिंग और रंगाई की पारंपरिक विधियाँ
किसी भी सूती धागे को रंगने से पहले उसकी उचित तैयारी बहुत आवश्यक होती है। कोरे सूत को सीधे रंगाई में डाल देना उचित नहीं माना जाता, क्योंकि उसमें प्राकृतिक अशुद्धियाँ रहती हैं। इनमें मोम, वनस्पति के छोटे टुकड़े, चर्बी तथा अन्य अशुद्ध पदार्थ शामिल हो सकते हैं। यदि इन अशुद्धियों को पहले दूर न किया जाए, तो रंगाई असमान हो सकती है, रंग ठीक से नहीं चढ़ता और धागे पर धब्बे भी पड़ सकते हैं।
इसलिए रंगाई से पहले सूत को गर्म क्षारीय घोल में उबालना, आवश्यकता होने पर ब्लीच करना और फिर उचित विधि से रंगना आवश्यक माना गया है। नीचे सूती धागों की तैयारी से लेकर डाइरेक्ट और वैट रंगों से रंगाई तक की विधियाँ दी जा रही हैं।
Visual 1: सूती धागे की तैयारी, ब्लीचिंग और रंगाई का चरणबद्ध प्रवाह।
1. धागों को उबालना
कोरे सूती धागे को रंगने से पहले उबालना चाहिए। यह प्रक्रिया धागे की अशुद्धियों को हटाने में सहायता करती है और धागे को रंग ग्रहण करने योग्य बनाती है। कोरे सूत में उपस्थित मोम, चिकनाई, वनस्पति अवशेष और अन्य प्राकृतिक अशुद्धियाँ रंगाई की गुणवत्ता को प्रभावित कर सकती हैं।
पाँच किलोग्राम सूत को उबालने के लिए निम्न घोल तैयार किया जाता है:
सामग्री
मात्रा
कास्टिक सोडा ठोस
100 ग्राम
साबुन
50 ग्राम
सोडियम सिलिकेट
50 ग्राम
पानी
100 लीटर
इस घोल में सूत को 4 से 5 घंटे तक उबालें। रंगाई में मृदु जल का प्रयोग करना चाहिए। कठोर जल के इस्तेमाल से रसायनों की खपत अधिक होती है और रंगाई में धब्बे पड़ सकते हैं। सूत को एक रात के लिए घोल में डुबोकर रखना चाहिए और अगले दिन साफ पानी से अच्छी तरह धो लेना चाहिए। यह विधि सामान्यतः सभी प्रकार के सूत के लिए उपयुक्त मानी जाती है।
व्यावहारिक टिप्पणी: रंगाई की अच्छी शुरुआत धागे की सफाई से होती है। यदि धागा ठीक से उबाला नहीं गया है, तो बाद की ब्लीचिंग और रंगाई दोनों प्रभावित हो सकती हैं।
2. विरंजन या ब्लीचिंग
सफेद सूत या हल्के रंगों की रंगाई के लिए सूत का ब्लीचिंग करना आवश्यक होता है। ब्लीचिंग द्वारा सूत के प्राकृतिक रंग को हटाया जाता है, जिससे उस पर हल्के या चमकदार रंग अधिक अच्छे ढंग से चढ़ते हैं।
ब्लीचिंग की मुख्यतः दो विधियाँ हैं:
हाइपोक्लोराइट विधि
हाइड्रोजन परॉक्साइड विधि
3. ब्लीचिंग पाउडर विधि
इस विधि में सामान्यतः ब्लीचिंग पाउडर का प्रयोग किया जाता है। अर्ध-ब्लीच किया हुआ सूत रंगाई के लिए अच्छा माना जाता है। उबले हुए सूत को 1 से 1.5 ग्राम प्रति लीटर उपलब्ध क्लोरीन वाले ब्लीचिंग घोल में सामान्य तापमान पर लगभग आधा घंटा चलाया जाता है।
इसके बाद सूत को धोकर 5 से 10 मिलीलीटर प्रति लीटर नमक के अम्ल के घोल में सामान्य तापमान पर लगभग आधा घंटा रखा जाता है। फिर धागे को अच्छी तरह पानी से धोया जाता है, ताकि अम्ल पूरी तरह निकल जाए।
पूर्ण सफेदी प्राप्त करने के लिए 5 किलोग्राम सूती धागे हेतु लगभग 700 ग्राम ताजा ब्लीचिंग पाउडर को 100 लीटर पानी में घोलकर ब्लीचिंग घोल तैयार किया जाता है। ब्लीच करने के बाद धुलाई की जाती है, फिर अम्ल के घोल से धुलाई और अंत में साफ पानी से अच्छी तरह धुलाई की जाती है।
सफेदी बढ़ाने के लिए टिनोपाल, खूबी व्हाइट या अमरव्हाइट को \(0.1\%\) से \(0.2\%\) के घोल में प्रयोग किया जा सकता है। इसके बाद सूत को निचोड़कर बिना धुलाई किए सुखाया जाता है।
ब्लीचिंग करते समय सावधानियाँ
ब्लीचिंग के समय धातु के बर्तन का प्रयोग नहीं करना चाहिए।
ब्लीचिंग के लिए ताजा घोल उसी समय तैयार करना चाहिए।
ब्लीचिंग करते समय धागे पर सूर्य की सीधी किरणें नहीं पड़नी चाहिए।
क्लोरीन की मात्रा बताई गई मात्रा के अनुसार ही होनी चाहिए।
4. हाइड्रोजन परॉक्साइड विधि
हाइड्रोजन परॉक्साइड विधि को अधिक सुरक्षित और उत्तम माना जाता है, क्योंकि इससे रेशों और पर्यावरण को अपेक्षाकृत कम नुकसान होता है। बाजार में सामान्यतः 10, 20, 100 और 130 आयतन शक्ति वाला हाइड्रोजन परॉक्साइड मिलता है।
हाइड्रोजन परॉक्साइड की आयतन शक्ति और वजन प्रतिशत का संबंध इस प्रकार है:
हाइड्रोजन परॉक्साइड की शक्ति
वजन अनुसार प्रतिशत शुद्धता
10 आयतन
3.04%
20 आयतन
6.08%
100 आयतन
30.40%
130 आयतन
39.52%
हाइड्रोजन परॉक्साइड से ब्लीच करते समय सामान्यतः सोडियम सिलिकेट का प्रयोग किया जाता है। तापमान लगभग \(80^\circ C\) से \(85^\circ C\) रखा जाता है।
सामग्री
अर्ध-ब्लीच
पूर्ण-ब्लीच
हाइड्रोजन परॉक्साइड
0.5 से 1 आयतन
2 से 4 आयतन
सोडियम सिलिकेट
2 ग्राम प्रति लीटर
8 ग्राम प्रति लीटर
ब्लीचिंग समय
लगभग 2 घंटे
लगभग 2 घंटे
उदाहरण के लिए, 5 किलोग्राम सूती धागे को पूर्ण ब्लीच करने के लिए 2 आयतन हाइड्रोजन परॉक्साइड और 4 ग्राम प्रति लीटर सोडियम सिलिकेट लिया जा सकता है। 100 लीटर पानी में 400 ग्राम सोडियम सिलिकेट और लगभग 1.560 लीटर हाइड्रोजन परॉक्साइड मिलाकर घोल तैयार करें। तापमान \(80^\circ C\) तक बढ़ाएँ और इस तैयार घोल में सूत को लगभग 2 घंटे चलाएँ। फिर धुलाई करके निचोड़ लें और सूत को सुखा लें।
Visual 2: ब्लीचिंग पाउडर और हाइड्रोजन परॉक्साइड विधि की तुलना।
5. डाइरेक्ट रंगों से रंगाई
डाइरेक्ट रंगों से रंगाई सूती धागे पर अपेक्षाकृत सरल विधि से की जा सकती है। रंग को घोलते समय इस बात का ध्यान रखना चाहिए कि रंग ठीक से घुल जाए और उसमें अवशेष या दाने न रहें।
रंग घोलने की विधि
रंग को मृदु जल या मृदु किए हुए जल में घोलना चाहिए। पहले थोड़े ठंडे पानी में रंग का चिकना पेस्ट बनाया जाता है। इसके बाद उसमें पर्याप्त मात्रा में उबलता हुआ गर्म पानी मिलाया जाता है और लगातार चलाया जाता है। घोल को पूरी तरह घुलने तक उबालना चाहिए।
रंगाई पात्र में धागे के वजन के अनुसार निम्न रसायन मिलाए जाते हैं:
रसायन
हल्के शेड में
मध्यम शेड में
गहरे शेड में
सोडा ऐश
0.5%
1%
2%
ग्लोबर साल्ट या साधारण नमक
5%
10% से 15%
20% से 30%
रंगाई के लिए \(40^\circ C\) से \(50^\circ C\) तापमान पर आवश्यक मात्रा में सोडा ऐश और आवश्यक मात्रा का आधा नमक धागे के 20 गुना पानी में मिलाकर रंगाई पात्र तैयार किया जाता है। पहले से उबाले या ब्लीच किए हुए सूती धागों को इस पात्र में डालकर लगभग 15 मिनट चलाया जाता है।
इसके बाद बचा हुआ आधा नमक रंगाई पात्र में डालकर लगभग 15 मिनट में तापमान धीरे-धीरे \(90^\circ C\) से \(95^\circ C\) तक बढ़ाया जाता है। इसी तापमान पर 35 से 45 मिनट तक रंगाई की जाती है।
गहरे शेड की रंगाई करते समय यह सलाह दी जाती है कि धागे को लगभग 15 मिनट तक रंगाई पात्र में ही रहने दिया जाए, जब तक पात्र थोड़ा ठंडा न हो जाए। अंत में सूती धागे को बाहर निकालकर निचोड़ लें और फिर सादे पानी में अच्छी तरह धो लें।
डाइरेक्ट रंगों से रंगाई की सावधानियाँ
रंगाई करते समय धागे को अच्छी तरह चलाते रहना चाहिए।
रंगाई सामान्य तापमान पर शुरू करनी चाहिए।
तापमान धीरे-धीरे \(60^\circ C\) से \(90^\circ C\) तक बढ़ाना चाहिए।
समान रंगाई के लिए लेवलिंग एजेंट जैसे सैरोपोर आर.एस.डी. को 1% की मात्रा में कपड़े या धागे के वजन के अनुसार शुरुआत में रंगाई पात्र में मिलाया जा सकता है।
6. डाइरेक्ट रंगों का धुलाई पक्कापन बढ़ाना
रंगे हुए धागे या कपड़े को 5% क्रोमियम एसीटेट के घोल में 30 मिनट तक डुबोकर रखने से धुलाई के प्रति पक्कापन सुधर सकता है।
एक अन्य विधि में 1 से 2 ग्राम प्रति लीटर डाइफिक्सर के घोल में सामान्य तापमान पर उपचार किया जाता है। यह विधि सरल और कम लागत वाली मानी जाती है।
7. धूप के प्रति पक्कापन बढ़ाना
नीला थोथा अर्थात कॉपर सल्फेट के 1 ग्राम प्रति लीटर घोल में सामान्य तापमान पर 15 मिनट तक उपचार करने से कपड़े पर कीट प्रकोप कम होता है और धूप के प्रति पक्कापन भी बढ़ता है। रंगे हुए धागे को छाँव में सुखाना उचित रहता है।
8. वैट रंगों से रंगाई
जब बहुत अधिक पक्के शेड की आवश्यकता होती है, तब वैट रंगों का प्रयोग किया जाता है। पक्के रंगों की श्रेणी में वैट रंगों को श्रेष्ठ माना जाता है। ये रंग पानी में अघुलनशील होते हैं, लेकिन कॉस्टिक सोडा और रंगकाट यानी हाइड्रोसल्फाइट ऑफ सोडा मिलाने से घुलनशील अवस्था में आ जाते हैं।
यदि रंगाई पात्र में रंग के अनुसार कॉस्टिक सोडा और रंगकाट उचित मात्रा में न मिलाए जाएँ, तो वैट रंग अवक्षेपित होकर तलछट बन सकता है। इसलिए रंगाई पात्र में रंग घुलनशील अवस्था में रहना चाहिए।
रंगाई से पहले यह जाँच लेना चाहिए कि रंग पूरी तरह घुल गया है। इसकी जाँच दो प्रकार के टेस्टिंग पेपर से की जाती है:
फिनॉफ्थलीन कागज: कॉस्टिक सोडा के घोल से लाल हो जाता है।
वैट का पीला कागज: रंगकाट के घोल में नीला हो जाता है।
यदि जाँच से पता चले कि रंगाई पात्र में कॉस्टिक सोडा या रंगकाट कम है, तो थोड़ी और मात्रा में ये रसायन मिला लेने चाहिए। ऐसा न करने पर हल्का शेड, दागी रंगाई और पक्केपन में कमी आ सकती है।
9. वैट रंगों की प्रचलित विधि
आवश्यक मात्रा में रंग लेकर टर्की रेड ऑयल में उसका पेस्ट बनाया जाता है। फिर अवकरण या वैटिंग के लिए आवश्यक मात्रा में गर्म पानी, कास्टिक सोडा और रंगकाट मिलाया जाता है।
इसके बाद निर्धारित तापमान पर रंगाई पात्र तैयार किया जाता है। उसमें आवश्यक मात्रा में पानी, कॉस्टिक सोडा और रंगकाट मिलाया जाता है। अवकरण किया हुआ रंग इस रंगाई पात्र में मिलाया जाता है। सूती धागे को इसमें 45 मिनट से 1 घंटे तक अच्छी तरह चलाया जाता है।
इसके बाद धागे को बाहर निकालकर निचोड़ लें और लगभग 30 मिनट तक रंग का ऑक्सीकरण होने के लिए हवा में फैला दें। कुछ रंगों, जैसे नीले शेड, में रंगाई के तुरंत बाद और ऑक्सीकरण से पहले धुलाई की जाती है। कुछ रंगों में ऑक्सीकरण और धुलाई के बाद धागे को नूरने के लिए धूप से बचाया जाता है।
रंगाई किए हुए धागे पर रंग का हवा में ऑक्सीकरण होने के बाद पानी से धुलाई करें। फिर गंधक के तेजाब, 168 डिग्री ट्वेडल शक्ति, के 2.5 मिलीलीटर प्रति लीटर पानी के घोल से धुलाई करें। इसके बाद साफ पानी से धो लें। तेजाब के पानी से धुलाई का काम सीमेंट या लकड़ी के बर्तन में करना चाहिए।
फिर रंगे हुए सूती धागों को 2 ग्राम साबुन और 1 ग्राम सोडा ऐश प्रति लीटर पानी के घोल में लगभग 30 मिनट तक सोपिंग करें। रंग का वास्तविक शेड और चमक उभारने के लिए पूरी तरह न चढ़े हुए रंग को निकालना आवश्यक होता है। इसके लिए सोपिंग अर्थात साबुन के घोल में उबालना बहुत महत्वपूर्ण है। इससे शेड का पक्कापन भी बढ़ता है।
Visual 3: वैट रंगाई में अवकरण, रंगाई, ऑक्सीकरण और सोपिंग का क्रम।
10. वैट रंगों से रंगाई की पाँच विधियाँ
वैट रंगों से रंगाई की पाँच विधियाँ मानी जाती हैं। इन विधियों में रसायनों की मात्रा और तापमान में अंतर होता है।
विधि संख्या 1: इस विधि में कॉस्टिक सोडा और तापमान अधिक होता है। रंगाई पात्र में नमक नहीं मिलाया जाता।
विधि संख्या 2: इस विधि में मध्यम मात्रा में कॉस्टिक सोडा और मध्यम रंगाई ताप होता है। इसमें बहुत थोड़ी मात्रा में नमक का प्रयोग किया जाता है।
विधि संख्या 3: इस विधि में कम से मध्यम मात्रा में कॉस्टिक सोडा और कम रंगाई ताप पर अधिक मात्रा में नमक का प्रयोग किया जाता है।
विधि संख्या 4: इस विधि में विधि संख्या 1 की अपेक्षा अधिक मात्रा में कॉस्टिक सोडा और रंगकाट यानी हाइड्रो का प्रयोग किया जाता है।
विधि संख्या 5: इस विधि को स्टॉक वैट रंगाई विधि कहा जाता है। इसमें कॉस्टिक सोडा और रंगकाट अलग से रंगाई पात्र में नहीं मिलाया जाता।
रसायनों की मात्रा शेड की गहराई और विधि के अनुसार अलग-अलग होती है। सामान्य रूप से हल्के शेड, मध्यम शेड और गहरे शेड के लिए कॉस्टिक सोडा, रंगकाट और नमक या ग्लोबर साल्ट की मात्रा अलग-अलग रखी जाती है। रंगाई का तापमान भी विधि के अनुसार लगभग \(25^\circ C\) से \(80^\circ C\) तक बदल सकता है।
11. वैट रंगाई में रसायनों की सामान्य मात्रा
रसायन
शेड की गहराई
विधि 1
विधि 2
विधि 3
विधि 4
विधि 5
कास्टिक सोडा ठोस
हल्का शेड 0.5% तक
425
175
140
600
165
कास्टिक सोडा ठोस
मध्यम शेड 0.5–2% तक
480
225–275
225
1100–1300
175
कास्टिक सोडा ठोस
गहरा शेड 2% से अधिक
550–600
275–350
300
1100–1300
200
रंगकाट / हाइड्रो
हल्का शेड 0.5% तक
175–225
175–225
175–225
350
170–180
रंगकाट / हाइड्रो
मध्यम शेड 0.5–2% तक
225–350
225–350
225–350
700–800
285
रंगकाट / हाइड्रो
गहरा शेड 2% से अधिक
350–450
350–450
350–450
700–800
350
नमक / ग्लोबर साल्ट
हल्का शेड 0.5%
—
225
450
—
—
नमक / ग्लोबर साल्ट
मध्यम शेड 0.5–2% तक
—
450–900
700–1400
1400
—
नमक / ग्लोबर साल्ट
गहरा शेड 2% से अधिक
—
1150–1850
1850–2700
2700
—
रंगाई तापमान
—
50–60°C
40–50°C
25–30°C
60–80°C
55–60°C
निष्कर्ष
सूती धागे की सफल रंगाई केवल रंग डालने की प्रक्रिया नहीं है। यह एक क्रमबद्ध तकनीकी प्रक्रिया है, जिसमें पहले धागे की अशुद्धियों को हटाया जाता है, फिर आवश्यकता अनुसार ब्लीचिंग की जाती है और उसके बाद उपयुक्त रंगाई विधि अपनाई जाती है। डाइरेक्ट रंगों से रंगाई सरल है, लेकिन वैट रंगों से रंगाई अधिक पक्कापन देती है।
वैट रंगों में रसायनों की सही मात्रा, तापमान, अवकरण, ऑक्सीकरण और सोपिंग का विशेष महत्व होता है। पुरानी वस्त्र-प्रक्रियाओं में जो सूक्ष्मता दिखाई देती है, वह आज भी उपयोगी है। चाहे धागे को उबालना हो, ब्लीच करना हो, रंग घोलना हो या रंगाई के बाद पक्कापन बढ़ाना हो—हर चरण धागे की अंतिम गुणवत्ता को प्रभावित करता है।
सामान्य सुरक्षा अस्वीकरण
यह लेख पारंपरिक वस्त्र-प्रक्रिया संबंधी शैक्षिक जानकारी के उद्देश्य से लिखा गया है। इसमें कास्टिक सोडा, अम्ल, ब्लीचिंग पाउडर, हाइड्रोजन परॉक्साइड, क्रोमियम एसीटेट, कॉपर सल्फेट और अन्य रसायनों का उल्लेख है। इन रसायनों का प्रयोग केवल प्रशिक्षित व्यक्ति द्वारा उचित सुरक्षा उपकरणों, वेंटिलेशन, माप-नियंत्रण और स्थानीय सुरक्षा नियमों के अनुसार ही किया जाना चाहिए।
घरेलू स्तर पर या बिना प्रशिक्षण के इन रसायनों का प्रयोग जोखिमपूर्ण हो सकता है। वास्तविक औद्योगिक प्रयोग से पहले विशेषज्ञ की सलाह अवश्य लें। लेखक इस जानकारी के प्रत्यक्ष प्रयोग से होने वाले किसी नुकसान, दुर्घटना या गुणवत्ता संबंधी समस्या के लिए उत्तरदायी नहीं है।
This is as per a brochure from CSTRI ( Central Silk Board)
Receipe
M:L- 1:30
Dye- X% on the weight of the material
Glauber Salt- 10% on the weight of the material.
Acetic Acid- 4-6% ( 40% strength)
Temperature: 85-90 deg C, pH-4-6, Time- 15 minutes
Procedure
- Preparation of dye solution: Dissolve required dye powder in boiling water in a separate beaker/vessel.
- Set the dye bath with required quantity of water.
- Add Glauber Salt
- Add dye solution.
- Enter the presoaked material at 40 deg C. Work for 10 minutes.
- Take out the material.
- Add acetic acid and stir well.
- Enter the material.
- Gradually raise the temperature to 85-90 deg C.
- Work for 35-40 minutes
- Take out the material followed by cold wash.
- Removal of excess water by using hydro extractor.
- Dyeing under shade.
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This is as per a brochure from CSTRI ( Central Silk Board)
Bleaching Receipe
M:L- 1:30
Soda Ash- 0.5 GPL or 1% on the weight of the material.
Sodium Silicate- 1.5 GPL
Hydrogen Peroxide- 20 MI/Lit
Temperature- 80 deg C, Time- 60 to 90 Min, pH-9
Procedure
-Take required quantity of water.
-Dissolve soda ash and sodium silicate
- Enter the material at 40 deg C
- Work for 5 min.
- Take out the material and add Hydrogen Peroxide
- Raise the temperature to 80 deg C
-Work for 60-90 min followed by cold wash.
- Removal of excess water by using hydro extractor.
Optical Whitening Receipe
M:L- 1:30
Ranipal WHN-3% on the weight of the material
Hydrose- 2 GPL
Temperature- 60-70 Deg C, Time-15 min, pH-9
Procedure
- Take required quantity of water.
- Add Ranipal WHN and hydrose ( Dissolve Ranipal in hot water)
- Enter the material at 40 deg C.
- Raise the temperature to 60-70 deg C
- Work for 15 minutes followed by cold wash.
- Removal of excess water by using hydro extractor.
- Drying under shade.
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This is as per a brochure from CSTRI ( Central Silk Board)
Receipe
M:L- 1:30
Soap- 5 GPL or 15% on the weight of the material.
Soda Ash- 1 GPL or 3% on the weight of the material
Temperature- 90-95 deg C., Time- 30 to 45 minutes, pH- 9.5 to 10.5
Methods/Procedure
- Dissolve soap and soda in the required amount of water.
- Enter the material at 40 deg C
- Raise the temperature to 90-95 deg C
- Work for 30-45 minutes
- Take out the material and hot wash for 10 minutes for 60 to 70 deg C.
- Followed by cold wash.
- Removal of water by using hydroextractor.
- Drying under Shade.
Single Bath Degumming and Bleaching
Receipe
M:L- 1:30
Soap- 5 GPL or 15% on the weight of the material.
Soda Ash- 0.5 GPL or 1% on the weight of the material.
Sodium Silicate- 1.5 GPL
Hydrogen Peroxide- 20 MI/Lit
Temperature - 85-90 deg C, Time- 60 to90 min., pH- 10
Procedure
- Take required quantity of water.
- Dissolve Soap, Soda Ash and Sodium Silicate
- Enter the material at 40 Deg C
- Work for 5 minutes
- Take out the material and add hydrogen peroxide.
- Raise the temperature to 85-90 deg C
- Work for 60 to 90 minutes followed by hot wash and cold wash.
- Removal of excess water by using hydro extractor.
- Drying in Shade
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This is as per a brochure from CSTRI ( Central Silk Board Bangalore)
Receipe
M:L- 1:30
Dye: X% on the weight of material.
Glauber Salt- 20% of the weight of material ( 1st Stage)
Glauber Salt- 20% of the weight of material (2nd Stage)
Soda Ash- 5% of the weight of material ( 1st Stage)
Soda Ash- 5% on the weight of material (2nd Stage)
Temperature ( Cold Brand)- 50 deg C
Temperature ( Hot Brand) - 60 deg C
pH-9, Time: 65-75 minutes
Procedure
Preparation of dye solution:
Dissolve required dye powder in boiling water in a separate beaker/vessel.
Set the dye bath with required quantity of water.
Add dye solution and add 20% Glauber salt and 5% soda ash at 1st stage.
Enter the material and work for 10 minutes.
Add 20% glauber salt and 5% sold ash at 2nd stage and work for 20 minutes.
For Cold brand reactive dyes, work for 45 minutes at 50 deg.
For hot brand reactive dyes, work for 45 minutes at 60 deg.
Take out the material followed by cold wash.
Remove excess water by using hydro extractor.
Dry under shade.
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It is hypochlorite of calcium and sodium. Bleaching powder on treatment with small quantities of dilute acid liberates hyopchlorous acid, whcih can easliy furnish nascent oxygen and thus acts as an oxidizing and bleaching agent. It is used for the following purposes:
1. As an oxidising agent in garment processing
2. For bleaching cotton, linen and wool.
3. In rendering wool unshrinkable.
2. Hydrogen Peroxide, H2O2
Hydrogen peroxide is a colorless, odorless, syrupy liquid in the anhydrous state. It is a powerful oxidizing agent. It destroys the color of some organic compounds and is used in garment and textile industry for bleaching delicate fabrics like wool, straw and silk.
3. Potassium Chlorate KClO3
Potassium chlorate is a white crystalline solid, which is soluble in water. On heating it decomposes to give oxygen. The ease with which it can lose oxygen, it acts as a strong oxidizing agent. It is used for garment printing.
4. Potassium Chromate
Potassium chromate is available in the form of lemon yellow crystals with no water of crystallization. In garment industry it is used as a mordant.
5. Potassium Dichromate
It is available in the form of orange red crystals. It is soluble in water. In neutral or acidic solution, potassium dichromate furnishes nascent oxygen and thus acts as an excellent oxidizing agent. It is used in garment industry as an oxidizing agent and as mordant in dyeing.
6. Potassium Permanganate
It acts as a powerful oxidising agent in neutral, alkaline or acidic solution and hence used in the garment industry as an oxidising agent.
7. Sodium Perborate
Sodium perborate is mainly used as a bleaching agent for a variety of fabrics namely wool, cotton, rayon, linen etc. It is also used as an oxidising agent and dye fixing agent.
8. Sodium Hypochlorite
Sodium hypochlorite liberates hypochlorous acid and thus acts as a powerful oxidizing and bleaching agent. It is used in textile and garment industry for bleaching process.
9. Sodium Bisulfite, NaHSO3
An aqueous solution of sodium bisulfite is obtained when an aqueous solution of sodium carbonate is saturated with sulphurdioxide. It is an important reducing agent and is used as an antichlor after bleaching garments with chlorine.
10. Sodium Hydrosulfite
It is used as reducing and bleaching agent in garment and textile industry. 11. Sodium Metabisulfite
On heating, it decomposes into sodium bisulfite and sulfur dioxide and hence it is an important reducing agent. It is used as an antichlor after bleaching garments with chlorine.
12. Sodium Sulfite
It forms colorless crystals very soluble in water. It is decomposed by dilute mineral acids with the evolution of sulfur dioxide. It is used as mild bleaching agent for silk and woollen fabrics and as an antichlor after chlorine bleach.
13. Sodium Sulfide
Its aqueous solution shows and alkaline reaction due to hydrolysis. It is used for manufacture of sulfur dyes and as reducing agent in garment industry.
14. Sodium Sulfoxylate Formaldehyde
It is also known as Rongalite C. It is a powerful reducing agent and exerts its full reducing action only at high temperatures. It finds extensive application in garment and textile industry for printing and stripping dyed fabric prior to re-dyeing.
15. Sodium Thiosulfate
It is also know as hypo. It is a colorless, crystalline and efflorescent substance. It is used as an antichlor after bleaching garments with chlorine.
16. Stannous Chloride: It is used as mordant in garment dyeing and printing.
17. Dextrin
It is a modified starch prepared by heat treatment of starch in the dry state, with or without the addition of small quantities of chemicals. It is a white powder, and finds extensive use as sizing and finishing agent.
18 Glucose
It acts as a strong and cheap reducing agent in garment industry.
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Acetic acid is a colorless and corrosive liquid with pungent smell of its own. It is miscible with water, alcohol and ether in all proportions. Acetic acid is used in garment industry for dyeing purposes.
2. Citric Acid
Citric acid is in the form of colorless, translucent crystals or a white granular to fine crystalline powder. It is used as sequestering agent, as mordanting agent in dyeing and cleansing agent for boiler water.
3. Formic Acid
Formic acid is a colorless and pungent smelling mobile liquid. It is miscible with water, alcohol and ether in all proportions. It acts both as an acid and as reducing agent due to presence of both carboxylic and aldehyde group. Formic acid is used in dyeing wool and cotton fabrics.
4. Hydrochloric Acid, HCl
Hydrochloric acid gas is a colorless, pungent smelling gas with acidic taste. It fumes in moist air and is extremely soluble in water.
5. Nitric Acid, HNO3
Nitric acid is a colorless fuming liquid when pure but may be colored yellow due to its dissociation products mainly nitrogen dioxide. It is a strong acid and acts as a powerful oxidizing agent. Nitric acid is used in the manufacture of dyes.
6. Oxalic Acid, HOOC.COOH.2H2O
Oxalic is a colorless, crystalline solid with two molecules of water of crystallization. Oxalic acid is used in garment and textile industry for the removal of ink stains from cloths and bleaching of straw for hats. Its antimony salts are used as mordant for dyeing and printing.
7. Liquid Ammonia, NH4OH
Ammonia is a colorless gas with characteristic pungent odor and an alkaline taste. It is used as a cleansing agent for removing grease in dry cleaning.
8. Caustic Soda ( Sodium Hydroxide), NaOH
Caustic soda is a deliquescent white crystalline solid, which readily absorbs moisture and carbon dioxide from the atmosphere. It is used for mercerizing cotton.
9. Soda Ash ( Washing Soda), Na2CO3
Sodium carbonate is a white crystalline solid containing water of crystallization. It is used in laundry as washing soda. It is also used for softening water.
10. Sodium Bicarbonate ( Baking Soda), NaHCO3
Sodium bicarbonate is available in the form of white crystals, sparingly soluble in water. It is alkaline in nature.
11. Sodium Silicate
Liquid alkaline Sodium silicate is mostly used in garment industry as a fixing agent and for rendering the garments fire proof.
12. Trisodium Phosphate, Na3PO4
It is a white crystalline solid soluble in water. It is used as detergent in garment processing.
13. Common Salt
It is used as to exhaust dyeing with direct and reactive dyes.
14. Diammonium Hydrogen Phosphate
It is used in printing paste as an acid liberating agent.
14. Glauber Salt, Na2SO4.10H2O
It is used in dyestuff, textile and garment industry. In textile and garment industry, it is added to the dye bath for cotton fabrics to promote dye exhaustion.
15. Magnesium Chloride
It is a colorless, crystalline deliquescent substance soluble in water. It is used in textile and garment industry for sizing, dressing and filling of cotton and woollen fabrics, for thread lubrication or carbonization of wool.
16. Tatar- Emetic
Potassium Antimonyl Tartarateis known as Tartar-emetic. It is used as mordant in large quantities in garment and textile industry. 17. Zinc Chloride
It is a white deliquescent solid exceedingly soluble in water. The concentrated aqueous solution of zinc chloride dissolves cellulose.
18. Zinc Sulphate ZnSO4.7H2O
It is a crystalline solid very soluble in water. It is used as mordant in printing.
---to be continued---
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I happen to attend the meet as a buyer. It was an experience to be remembered for a long time.
The event was organised after much thought had been put into place, as is evident by the arrangements. The idea of prefixed B2B meetings was novel and ensured that the participants really engaged into business interactions.
As the first effort, kudos to the organisers who managed to bring in more than 350 foreign and domestic buyers and provided for the hospitality. The results were encouraging as more than 350 million US dollar worth of business was transacted in those four days.
A very interesting idea was of business fashion shows. That brought in lots of crowed and the buyers could see the garments in action.
I managed to meet more than 40 sellers all across the Rajasthan. More than that interaction with more than 100 foreign buyer gave me a pulse of the market and trends.
There is a need to bring in more exhibitors of traditional fabrics.
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The percentages of various costs that add up to the garment cost are as follows:
1.Raw Material cost: 50%
2.Direct labour Cost: 20%
3.Indirect Labour charges and factory overheads: 30%
The raw material cost ranges from 40% for hosiery to 60% for lingerie. The cost of fabrics is 80% of the cost of raw material.
The fabrics can be broadly divided into the following three categories:
1.Tubular Knitted Fabric
2.Narrow open width fabric: The fabric width can accommodate two body pieces. Maximum market efficiency can be achieved if the number of smaller pattern pieces in the garment are relatively more.
3.Wide open width fabric: This type of fabric is having a width of 1.5 meters and three body pieces can be placed in the width of the fabric.
Fabric Losses
During the cutting process two types of fabric losses occur:
1.Marking Loss
2.Spreading Loss
Marking Loss arises due to the gap and the nonuseable areas at places between the pattern pieces of a marker. Marker efficiency indicates the amount of marking loss.
Spreading loss is the fabric loss outside the marker. The various fabrics outside the marker are classified into different groups:
1.End of Ply Loss
2.End of Piece Losses
3.Edge Losses
4.Splicing Losses
5.Remnant Losses
6.Ticket length Losses
1. End of Ply loss: The flexibility, limpness, extensibility alongwith the limitation of the spreading machinery necessitates an allowance of some fabric at the end of each ply. These losses may be upto 2 cm at each end or 4 cm per ply.
The end of ply loss is 1-2% of the total fabric usage.
2. End of Piece(Thaan) Losses: In textile industry, fabrics are produced and processed in different batches. This makes the fabric ends unsitable for use due to marks or distortions created.
The end of piece varies from 0.5-1% of the total fabric usage.
The loss is minimized if the average length of pieces that are purchased is increased.
3. Edge Losses: In normal practice during marker planning, the width of the marker is kept a few centimeters less than the edge-to-edge width of the fabric. The marker is made according to the usable width of the fabric. The usable fabric width depends upon the quality of the selvedge, the consistency of fabric width, and also on the precision of edge control during spreading. Let the fabric edge-to-edge width is 100 cm, and the marker width is 3 cm less than the fabric width. The edge loss is 3%. If the fabric edge-to-edge width is 150 cm, the loss is 2%.
Thus wider width has other benefits besides improved marker efficiency.
4. Splicing Losses: Splicing is the process of overlapping cut ends ( the end of one length of the fabric and the beginning of the other) of two separate pieces of the fabrics so that the spreading is continuous. Splicing is necessary as one roll of fabric is finished and the next taken into use.
Also during spreading there may be some objectionable fabric faults, which make the product unsalable or substandard. These fausts are removed by cutting the lay at the fault point and incorporating splicing position into marker plans.
During splicing the splicing line should be so selected that none of the pattern pieces contains the fault is incomplete.
The position of the splice lines also dependent on the quality of the fabric being spread. If cutting out faulty material at the lay is a regular requirement, it is vital that the markers are provided with clearly defined splice lines.
The splicing losses may vary up to the 5% of the total fabric usage.
5. Remnant Losses: Remnant lengths are produced whenever companies separate different shades of fabric pieces and lay up only complete plies.
Remnants are also generated when short lengths of material are left over after the completion of the lay, and are returned to the stores.
All remnants are put to one side and cut separately.
6. Length Losses ( L Losses): Woven fabrics and some knitted fabrics are sold by length. Each fabrics piece is measured by the fabric supplier and a ticket is attached to each piece indicating the length for which the customer is invoiced. In many cases the gross length and the net length are marked in the ticket. This loss can be reduced by inspecting the length of the incoming fabric and reporting the fabric supplier in case of yardage short.
What is FPT and GPT in Garment and Fabric Testing?
In garment manufacturing, the product is not judged only by how it looks at the time of shipment.
A garment may look perfect on the inspection table, but the real test begins when the customer
starts using and washing it. This is where FPT and GPT become important.
FPT means Fabric Package Test or Fabric Performance Test.
It checks whether the fabric is suitable for garment production.
GPT means Garment Package Test or Garment Performance Test.
It checks whether the finished garment will perform satisfactorily after washing and use.
Simple difference:
FPT asks: “Is this fabric technically fit for production?”
GPT asks: “Will the finished garment behave properly after customer use?”
Visual 1: Flow from fabric testing to garment performance testing.
Why are FPT and GPT Required?
In apparel production, many problems are not visible in the beginning. A fabric may shrink after
washing. A seam may open. A dark colour may bleed. A print may fade. A button may come off.
A zipper may not move freely after wash. These failures may not be noticed during normal visual
inspection, but they can lead to customer complaints, returns and brand damage.
FPT and GPT are therefore preventive tests. They help the buyer, manufacturer and merchandiser
identify risk before bulk production or before shipment.
What is GPT: Garment Package / Performance Test?
GPT is performed on finished garments. The main purpose is to check how the garment performs
after washing as per the care label. The test tries to simulate the way a customer will wash and use
the garment at home.
Generally, three identical garments are required for GPT:
One garment for dimensional stability — to check shrinkage or growth after washing.
One garment for appearance evaluation — to observe change in look, handle, pilling, puckering, twisting or other defects.
One garment for seam slippage and seam strength — to check whether seams remain secure after washing and stress.
For button pull testing, a mock placket or mock patti may be prepared with buttons attached to it.
This helps test button attachment strength without depending only on the garment sample.
Important Points Checked in GPT
Dimensional stability: Does the garment shrink or grow after washing?
Appearance after wash: Does the garment still look acceptable?
Puckering: Are seams or panels showing unwanted wrinkling?
Pilling: Are small fibre balls appearing on the surface?
Seam strength: Are seams strong enough for normal use?
Seam slippage: Are yarns slipping near the seam?
Zipper movement: Does the zipper still move freely?
Button attachment: Are buttons securely attached?
Colour change: Has the garment faded after washing?
Staining: Has colour transferred to other parts or adjacent fabrics?
Practical note for merchandisers:
GPT is not only a laboratory formality. It tells whether the customer will receive a garment that
remains wearable and presentable after washing.
Visual 2: Key checkpoints in Garment Performance Testing.
How Many Washes are Done in GPT?
The number of washes depends on the buyer’s requirement, product type and market. In many cases,
GPT may be done after one wash or after three washes.
A general industry observation is that some buyers require testing after one wash, while others may
ask for three washes. The important point is that the washing method should follow the care label
and the buyer’s approved test protocol.
For example, if the care label says machine wash at 40°C, the garment should be tested according
to that instruction. If the garment is labelled dry clean only, the test route will be different.
What is FPT: Fabric Package / Performance Test?
FPT is performed on fabric before or during the approval stage. It helps decide whether the fabric
is technically suitable for making garments. If the fabric itself is weak, unstable or colourfastness is
poor, then the finished garment will also carry those risks.
Usually, around 3 metres of fabric may be required for a complete fabric testing package, although
the exact requirement depends on the laboratory and buyer protocol.
Common Tests Included in FPT
Test
What it Checks
Why it Matters
Yarn Count
Fineness or coarseness of yarn used in the fabric
Helps confirm whether the fabric matches the approved specification
Construction
Ends per inch and picks per inch, or loop structure in knits
Affects weight, strength, cover, handle and appearance
GSM
Grams per square metre
Indicates fabric weight and helps check consistency
Fibre Composition
Actual fibre content such as cotton, polyester, viscose, silk, wool etc.
Important for labelling, costing, performance and legal compliance
Tensile Strength
Resistance of fabric to breaking under pulling force
Important for durability and end-use performance
Tear Strength
Resistance to continuation of a tear
Important for garments exposed to stress, abrasion or snagging
Colourfastness to Washing
Colour change and staining during washing
Prevents customer complaints related to bleeding and fading
Colourfastness to Rubbing
Colour transfer during dry and wet rubbing
Important for dark colours, denim, prints and contrast garments
Colourfastness to Perspiration
Effect of acidic and alkaline perspiration on colour
Important for garments worn close to the body
Colourfastness to Water
Colour bleeding or staining when fabric is exposed to water
Important for wet handling, washing and rainy conditions
Shrinkage
Dimensional change after washing or processing
Critical for garment fit and size stability
FPT vs GPT: The Main Difference
Point
FPT
GPT
Full Form
Fabric Package / Performance Test
Garment Package / Performance Test
Stage
Before or during fabric approval
After garment is made
Sample
Fabric length, often around 3 metres depending on lab requirement
Finished garments, usually multiple identical pieces
Shrinkage, appearance, seam strength, seam slippage, button pull, zipper movement
Purpose
To approve fabric for production
To approve garment performance before shipment
Visual 3: FPT versus GPT — fabric approval compared with garment approval.
Why FPT Alone is Not Enough
A fabric may pass all fabric tests and still create a problem in garment form. This happens because
garment performance depends not only on fabric, but also on pattern, sewing thread, seam type,
fusing, trims, washing method and finishing.
For example, a fabric may have acceptable shrinkage as a flat fabric, but the finished garment may
still twist, pucker or lose shape after washing. This is why GPT is necessary even after FPT approval.
Why GPT Alone is Also Not Enough
If only GPT is done, the problem may be identified too late. By the time the garment is ready, cutting,
stitching and finishing costs have already been incurred. If the garment fails at this stage, the loss is
much higher.
FPT helps catch fabric-related risks early. GPT confirms whether the garment as a complete product
is acceptable.
Best practice:
FPT should be used as an early warning system. GPT should be used as the final confirmation of
product performance.
Common Mistakes in Understanding FPT and GPT
Mistake 1: Thinking that FPT and GPT are the same. They are related, but not the same.
Mistake 2: Doing GPT only for export orders. Domestic customers also wash and use garments.
Mistake 3: Ignoring care label conditions during testing.
Mistake 4: Treating lab testing as paperwork instead of risk control.
Mistake 5: Not comparing the tested garment with the original unwashed garment.
Mistake 6: Forgetting trims such as buttons, zippers, fusing and elastic.
Practical Checklist for Merchandisers
Before approving fabric or garments, a merchandiser should ask:
Has the fabric test report been received and reviewed?
Is the fabric construction matching the approved specification?
Is the GSM within tolerance?
Is fibre composition matching the claim?
Are colourfastness results acceptable for the garment end use?
Is shrinkage within buyer tolerance?
Has the garment been washed according to the care label?
Is the garment appearance acceptable after wash?
Are seams, buttons, zippers and trims performing properly?
Has the report been approved before bulk shipment?
Conclusion
FPT and GPT are two important testing stages in apparel quality control. FPT checks the fabric before
it becomes a garment. GPT checks the finished garment after washing and use simulation. Together,
they help reduce production risk, customer complaints and product failure.
For a merchandiser, buyer or quality professional, the key lesson is simple: do not look at testing as
a formality. Testing is a way of predicting customer experience before the customer actually uses the
product.
Research Findings Related to FPT and GPT
The terms FPT and GPT are commonly used in the apparel industry, but research papers usually discuss the individual performance areas covered under these tests, such as shrinkage, dimensional stability, seam strength, colourfastness, pilling, tensile strength and garment durability.
The following research findings help us understand why Fabric Performance Testing and Garment Performance Testing are important in practical apparel quality control.
Research Area / Article
One Important Finding
Relevance to FPT / GPT
Physical garment durability
Guo et al., “A framework for measuring physical garment durability”
Garment durability is difficult to measure through one simple test because real-life garment use involves washing, wearing, rubbing, stretching and repeated handling.
This supports the need for GPT, because the finished garment should be tested as a complete product, not only as a fabric sample.
Garment failure causes
Cooper et al., “Garment failure causes and solutions”
Common reasons for garment failure include pilling and colour fading, both of which affect the customer’s perception of quality.
This supports including appearance change, pilling and colour change checks in GPT, and colourfastness checks in FPT.
Seam performance of knitted fabrics
Bansal, Sikka and Choudhary, “Seam performance of knitted fabrics based on seam strength and seam efficiency”
Seam strength depends on fabric type, seam angle, needle size and construction. Cotton and cotton/lycra knitted fabrics showed lower seam strength than polyester/cotton fabrics.
This is directly relevant to GPT, because a garment may fail at the seam even when the fabric itself appears acceptable.
Dimensional stability after domestic washing
Longurova et al., “The effect of fabric structure parameters on dimensional stability after domestic washing”
In 100% cotton woven fabrics, shrinkage occurred after domestic washing, and shrinkage was influenced by fabric structure, cover factor and weave factor.
This is relevant to both FPT and GPT. FPT helps predict fabric shrinkage, while GPT confirms whether the finished garment still maintains fit after washing.
Seam strength prediction in denim jeans
Manzoor et al., “Machine learning prediction model for seam strength of five-pocket denim jeans”
Seam strength in denim jeans was strongly influenced by thread count, stitch density, fabric weight and seam type.
This supports GPT because garment durability depends not only on fabric, but also on stitching parameters and seam construction.
Key learning from research:
FPT should not be treated as only GSM, fibre content and construction testing. It should also help predict shrinkage, colourfastness, strength and fabric stability. GPT goes one step further by checking whether the complete garment system — fabric, seam, thread, trims and washing — will perform satisfactorily for the customer.
General Disclaimer
This article is intended for educational and general textile understanding only. Testing requirements,
sample size, wash cycles, acceptance criteria and test methods may vary by buyer, product category,
country, laboratory and applicable standards. For commercial approval, always refer to the latest
buyer manual, applicable ISO/AATCC/ASTM/BIS standards and accredited laboratory reports.
The production process of the three fibers has been convered elsewhere in the blog. Here I would like to discuss some of the properties useful for fabric buyers for comparison.
In dry state viscose is only slight weaker than cotton. However, in the wet state, the strength is about 38% that of cotton. That makes it a very tricky fiber to blend with cotton and subsequent dyeing with cotton. The fabric undergoes changes in shape when wet processing.
Also strength of cotton increases when wet- being 1.14 times that in dry state. However, for viscose it is about 0.5 times that in dry state. This necesssitates that the viscose should be dry cleaned rather than ordinarily washed.
Modal's strength is comparable to cotton in dry state. In wet state, it is about 78% of the cotton strength. For Tencel, it is much more than cotton both in dry and wet state.
A table comparing the properties of the three is given below:
The above table represents three fibers from Birla. VSF is the first generation viscose. Modal is second generation and Tencel is the third generation viscose.
This Link describes the precautions to be followed in viscose processing.
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I just wish I could use this while I was a student.
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A very popular fabric is made in the Bijnor cluster where the picks are crammed after every inch or so so as to form distinct cords which in the market is called as pintuck. The fabric has a popularity as a fabric for Indian ethnic garments for mens and ladies.
The technique of weaving uses dobby mechanism on powerloom with four shafts. Two warping beams are used. The upper beam is at lower tension than the lower beam. The upper beam is used to make a shed for the crammed in picks whereas lower beam makes the ground fabric.
The order of drawing in is 1-3-2-4. Shafts Number 1 and 2 ( counted from the front) are used for weaving ground weave whereas 3 and 4 for the pintucking operation.
Here are some pictures. I have also uploaded a video ( some part of it to be seen by looking sideways).
A view of the top warp beam
A view of the bottom warp beam
Dobby and dobby chain
Final Fabric
The two warp beams
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