Today Post::Wool Fibre | The Basic Things About Wool

What is Wool? Wool is a protein fiber and it is produced by the animals known as sheep. It is unique fire with scales on its surface. Wool, is a multi-cellular fiber and very expensive in price.Wool producers in the world: 1. Australia 2. Russia 3. New-Zealand 4. USA 5. UK 6. South-Africa 7. France 8.Turkey 9. Brazil 10. China 11.Oajustab 12.Canada 13.India 14.Etc.Some Important

Today Post::Pretreatment of Fabric before Dyeing and Printing

To produce colored Fabric whether dyed or printed needs pre-treatment of those fabrics of those fabrics before dyeing and printing. The pretreatment operations involved for cotton fabric are described systematically below:Singeing: it is the process of burning out projecting hairy fibres from surface of the grey fabric by assigns the fabric through a gas flame. Both sides of the fabric are burnt

Today Post::Precautions to be taken before Garments Dyeing

Garments made from cotton grey fabric are dyed in garments form n the garments dyeing machine. Before garments dyeing some precautions are needed to avoid dyeing problems that may occur during garments dyeing. The precautions are discussed below:1. Garments design should be made from engineering point of view.2. if garmet is made after desizing, scouring and bleaching of grey fabrics and then

Today Post::Garments Production and Textile Export Information

Garments are produced in the garments factories on industrial basis for all the people of a specific country. Bangladesh is one of the garments producing & exporting country in the world market. At present, there are about 4500 garments factories running in Bangladesh. Growth of garments factories started in Bangladesh around 1980. Around 1980, garment production & export business was almost

Today Post::Textile Mills

In Bangladesh, visiting different Textile Mills it is found that a very few of the industry are conscious about the environmental policies, working environment, remuneration, Effluent Transfer Plant (ETP) etc. It is hopeful news that some of the industries are implementing the facts now. Now let ourselves to know the fact what should have the industries.1. A Textile Mill should have the basic

Today Post::Weaving=?UTF-8?B?4oCd?=+=?UTF-8?B?4oCd?=Spinning

Weaving and Spinning is related each other. One is impossible except other. Before going to process of weave, we must have to have in our hand some yarn, which I can get from the process of Spinning. So it can be said that "weaving+spinning" is most crucial fact on textile processing. Firstly I will discuss about something of spinning. The last step of spinning is Ring Spinning. Ring Spinning is

Today Post::What is cellulose?

Cellulose is and active chemical with three OH groups attached to each glucose inside. Those in the 2 and 3 positions behave as secondary alcohols; the hydroxyl in the 6th position acts as a primary alcohol.Cellulose is the basis of all plant fibres. It has an empirical formula (C6H10O5)n. t is a polymeric material formed by condensation of glucose.

Today Post::Wool Fibre | The Basic Things About Wool

What is Wool? Wool is a protein fiber and it is produced by the animals known as sheep. It is unique fire with scales on its surface. Wool, is a multi-cellular fiber and very expensive in price.Wool producers in the world: 1. Australia 2. Russia 3. New-Zealand 4. USA 5. UK 6. South-Africa 7. France 8.Turkey 9. Brazil 10. China 11.Oajustab 12.Canada 13.India 14.Etc.Some Important

Today Post::To knit | Types of Knitting Machines

To know more about Knit just follow this link: http://texarticles.blogspot.com/2009/06/knit-and-purl-stitches.htmlTo knit means knitting. And the knitting is done by using two machine named Warp Knitting Machine and Weft Knitting Machine. To knit a fabric the weft knitting machine is used exclusively. Now I will discuss something about weft knitting machine.Weft Knitting Machine:The knitting

Today Post::Knit and Purl Stitches

Knit and purl stitchesIn securing the previous stitch in a wale, the next stitch can pass through the previous loop either from below or above. If the former, the stitch is denoted as a knit stitch; if the latter, as a purl stitch. The two stitches are related in that a knit stitch seen from one side of the fabric appears as a purl stitch on the other side.The two types of stitches have a

Today Post::Introductory of Garments Manufacturing

Garments ManufacturingThe processing steps and techniques involved in the manufacturing garments for the large scale of production in industrial basis for business purposes is called garments manufacturing technology. Garments factories are classified according to their product types are as follows:Garments Factory—-1. Woven Garment Factory.2. Knit Garments factory3. sweater Garments

Today Post::Cotton

Definition: Cotton is the backbone of world's textile trade. Cotton is essential cellulose. It is attached to the seeds of plants of the Mallow Family. Many of our everyday textiles are made by cotton. Cotton fabrics are hand wearing and capable of infinite verity of weave and coloring.Cotton Breeding: cotton plant gossypium belongs to the genus malvaceae. The breeds can be classified on a

Today Post::knitting | To Knit

Knitting is a method by which thread or yarn may be turned into cloth. Knitting consists of loops called stitches pulled through each other. The active stitches are held on a needle until another loop can be passed through them.Knitting may be done by hand or by machine. By hand, there are numerous styles and methods. Flat knitting, which can be done on two straight needles or a circular needle,

Today Post::Introductory of Garments Dyeing

Garments DyeingIntroductory Ideas of Garments DyeingGarments dyeing is a new technology for us but it is actually using in the European countries for last 70 years. At first this technology applied on woolen and silk garments but now it is applied on polyester, nylon, acrylic, and also extessivelyu on cotton garments. Popularity of garments dyeing is increasing in France, Italy, Spain,

Today Post::Dyeing Machine- Sample

Sample Dyeing Machines:Sample Dyeing Machine - as the name suggests these machines are made available as sample to the buyer’s needs. These machines are quite popular in the industry. It is successfully applied for dyeing of various types. For example it is used for the atmospheric dyeing of substrates like fabrics, fibres, yarns at heightened liquor ratios either for development or for

Today Post::Different Dyestuff used in Fabric Dyeing

Different types of dyestuff used in Fabric DyeingDirect Dyes: These dye staffs are generally sodium salt of sulphonic acid. They have direct affinity to cellulosic fibre. They are water soluble and need salt addition in the dye bath should be applied at alkaline or neutral condition. Poor fastness to wash but cheaper.Basic Dyes: These are generally ammonium, sulphonium or auxonium salt famous

Today Post::Cotton Fabric Dyeing With Reactive Dyes

Cotton Fabric Dyeing process with Reactive DyesCotton fabric after pre-treatments e.g desizing, scouring & bleaching can be dyed using the following recipe:Reactive Dyes————————–X%Sequestering agent—————–0.5 G/LWetting agent———————–0.1-0.5 G/LAnt-creasing agent——————0.5-2.0G/LSalt————————————10-80 G/LSoda————–

Today Post::Cotton

Definition: Cotton is the backbone of world's textile trade. Cotton is essential cellulose. It is attached to the seeds of plants of the Mallow Family. Many of our everyday textiles are made by cotton. Cotton fabrics are hand wearing and capable of infinite verity of weave and coloring.

Cotton Breeding: cotton plant gossypium belongs to the genus malvaceae. The breeds can be classified on a genetic basis and chromosomes in the body cells.
New world types:- Gossypium Hirsutaum
Gossypium Brasilence
Gossypium Barbadence
Gossypium Peruvinum
Gossypium Purpurasems

Old world types:
Gossypium Aboreum
Gossypium Nanking
Gossypium Herbaceum

At present time the following are cultivated world wide-
Gossypium Hirsutum-87%
Gossypium Barbadense-8%
Gossypium Arborium + Gossypium Herbaceum—5%

Cotton growing countries:
Now a days cotton is cultivated in approximately 75 countries on an average of 32 million hectors. This is approximately 0.8% of the cultivated serface of the earth. The world wide annual production of ginned cotton is 20 million ton. This is 50% of the textile fibres processed between 4 and 6 million ton of the cotton produced is exported.

The most important producers are:– USA, Russia, Pakistan, India, China, Australia, Sudan, Paraguay, Brazil, Egypt, Mexico, Turkey, Canada, Europe, Etc.

The process sequence of Cotton production / Cultivation:

1. Formation of Cotton Fibre
2. Fibre Growth
3. Ring Growth
4. Effect of Growth Condition( Matured fibre, immature fibre, dead fibre).

Cotton Harvesting:
The process of pick up cotton from the field is known as harvesting. There are two types of harvesting—
1. Manual Harvesting
2. Mechanical Harvesting.

Ginning: The process of separating cotton fibres from seeds is called ginning. There are two types of ginning machines. Such as— 1. Saw Gin (for low to medium quality fibres)
3. Roller Gin (For high quality fibres).

Commercial varieties of cotton:
1. Very fine and lustrous—length 2—3 "
2. Average fine and little lustrous—length –1-2"
3. Short fibres or course fibres with no lustrous—less the 1"

Chemical composition of cotton:

Cellulose: 94%
Protein: 1.5%
Wax: 0.5%
Pectin Materials: 1%
Small amount of acids, sugar and pigments: 2%

To Read More About Cotton Please see at —–Cotton Properties

Today Post::What is cellulose?

Cellulose is and active chemical with three OH groups attached to each glucose inside. Those in the 2 and 3 positions behave as secondary alcohols; the hydroxyl in the 6th position acts as a primary alcohol.
Cellulose is the basis of all plant fibres. It has an empirical formula (C6H10O5)n. t is a polymeric material formed by condensation of glucose.

Today Post::Precautions to be taken before Garments Dyeing

Garments made from cotton grey fabric are dyed in garments form n the garments dyeing machine. Before garments dyeing some precautions are needed to avoid dyeing problems that may occur during garments dyeing. The precautions are discussed below:

1. Garments design should be made from engineering point of view.

2. if garmet is made after desizing, scouring and bleaching of grey fabrics and then dyed in garments form, then the possibility of problems will be reduced,

3. if possible, garments should be made from the grey fabrics of the same lot and same source.

4. the seams should not be too tight or too loose especiallu in the areas containing elastic like waistband, cuff aetc which may create irregular dye penetration resulting irregular dyeing.

5. the garmens which are produced from woven and knitted fabrics combindly, he knit fabric should be pre-shrunked, otherwise seam pucker may develop after garments dyeing.

6. if the garment fabric is of mixed fibres, during gaments dyeing, dye selection should be done carefully, having equqal dye pick up to avoid irregular dyeing.

7. poor quality metals should bot be used as accessories in the garments, which may vbe damaged duing dyeing by the action of salt and alkali. If any metal component is used in the garments should be made from nickel or its alloy.

8. sewing thread used for making the garment should be of same fibre like the garment fabric, other43wise colour difference may occur between garments fabric and sewing thread.

9. button used in the garments should be selected carefully. Buttons made from casin, cellulose, mylon etc. may be damaged during garments dyeing but polyester button is safe in this project.

10. if elastic is used in the garments and the elastic is made from natural rubber of polyurethance fibre like lycrea amy create problelm during garments dyeing. To avoid such problem dye should be selected made of copper free. During bleaching, polyurethance fibres may be damaged by the chlorine. Polyester type elastomeric fibre is safe in peroxide bleaching.

11. interlining is used in most garments. Only those interlinings should be sed in the garments to be dyed only recommended for garments dyeing, otherwise the performance of interlining may be destroyed.

12. the garments made from compactly woven cotton fabric should be dyed with hot brand reactive dyes, otherwise problem of irregular dye penetration may occur.

13. for some specific colour, if specific dyes are dused then the dyeing cost will be lower. For example, navy blue and black colour could be procuce in the garments by using sulpher dyes at lower cost.

14. presence of mineral impurities in the cotton fibres may vary which may impede the stability of peroxide liquor during bleaching with bydrogen peroxide. Even insoluble compounds may form during hydrogen peroxide bleaching. Those insoluble compounds may redposit on chemicals are available to avoid such problem.

15. Crease marks may develop in the cotton garments during dyeing. To avoid such problem, special chemicals like "Imacol Brand" may be used.

Today Post::Pretreatment of Fabric before Dyeing and Printing

To produce colored Fabric whether dyed or printed needs pre-treatment of those fabrics of those fabrics before dyeing and printing. The pretreatment operations involved for cotton fabric are described systematically below:

Singeing: it is the process of burning out projecting hairy fibres from surface of the grey fabric by assigns the fabric through a gas flame. Both sides of the fabric are burnt out by the flame. It helps in subsequent chemical process of the fabric. After dyeing or printing of singed fabric, brightness and luster of color and fabric becomes better.

Desizing: it is the pr4ocess of removing starch materials present in the gray fabric. Generally enzyme is used to degrade and remove the starch present in the grey fabric. If those size materials are not removed from the grey fabrics, then the subsequent chemical treatments on the fabric will be irregular, which will cause he defective dyeing and printing.

Scouring: It is the process of removing natural impurities present in the cotton fibre. The natural impurities are pectin's, pectos, ash, wax, mineral compounds, etc. if those impurities present in the cotton fibres are not removed, then it will be difficult to dye or print the fabric uniformly. Normally caustic soda ash is used as main reagent fro scouring of cotton fabric.

Bleaching: It is the process of removing natural coloring matters present in the cotton fibre. For his purpose, hydrogen peroxide, bleaching powder or other bleaching agents are used. Hydrogen peroxide is the best and most commonly used bleaching agent. If this bleaching treatment is not carried out before dyeing or printing hen the color yield and shade matching may be a great problem.

Mercerization: It is a special chemical pre-treatment on cotton fabric t improves the properties and performance of cotton fabric. The cotton fabric is treated under tension in the 20% caustic soda solution which is called mercerization many properties of cotton fabric is improved, some of them are mentioned below:

Increases fabric strength
Increases absorbency power
Increases fabric luster
Increases fabric softness and handle property
Reduces dye consumption
Reduces chemical consumption in dyeing.

Today Post::Cotton fibre | what is Cotton Fibre | Cotton Fibre Properties

Cotton is a natural vegetable fibre produced in the cotton plant in many countries of the world even in Bangladesh also. Some important properties of cotton fibres are discussed very briefly below:

Length:
Physically the individual cotton fibres consist of a single long tubular cell. Its length is about 1200-1500 times than its breadth. Length of cotton fibre varies from 16mm to 52 mm depending upon the type of cotton.
Indian cotton- 16-25 mm
American cotton- 20-30 mm
Sea Island- 38-52 mm
Egyptian cotton- 30-38 mm

Fineness:
Longer the fibre, finer the fibre in case of cotton fibre. It is expressed in term of decitex and it varies from 1.1 to2.3 decitex.
Indian= 2.2-2.3dtex
American= 2.1-2.2 dtex
Egyptian= 1.2-1.8 dtex
Sea Island= 1.0-1.1 dtex
Fineness may be more in case of immature fibre. So it is necessary to express maturity with fineness.

Strength and extension:
Cotton fibre is fairly among natural fibres in relation to tenacity which is 3-3.5g/dtex. Its tensile strength is between wool and silk fibre but disadvantage is low extension at break which is 5-7%.

Elastic properties:
Recovery from deformation of cotton fibre, yarn or fabric from applied load is very low. By applying heat it can't be achieved. This property can be achieved by -1.Chemical treatment to improve crease recovery, but the problem is the materials become harsher due to chemical treatment 2. blending or mixing of cotton with elastic fibre, e.g. polyester, blend ratio depends on the end use of the fabric. The initial modulus is fairly high=0
5 g/dtex (wool=0.25 g/dtex)

Cross-section:
Cross-section of cotton fibre is some what ribbon like. The cell wall is rather thin and the lumen occupies about two-third of the entire breadth and shows up very prominent in polarized light. Fibre cross-section becomes round when mercerized.

Appearance:

Cotton fibre is fairly short, fine and creamy white color. Color of the fibre depends on soil of growth. By adding chemicals in the soil, color of the cotton fibre may be varied.

Crimp:

Cotton fibre is more or less twisted on its longitudinal axis which cab not be seen from out side is called convolution. The twist in the fibre does not to be continuous in one direction i.e. if at first right direction, then left direction. This property of cotton fibre helps in spinning.

Today Post::Courses and Wales of Knitting | Knitting Needles Loop

Courses and wales


Structure of stockinette, a common knitted fabric… The meandering red path defines one course, the path of the yarn through the fabric. The uppermost white loops are unsecured and “active”, but they secure the red loops suspended from them. In turn, the red loops secure the white loops just below them, which in turn secure the loops below them, and so on.


Alternating wales of red and white knit stitches. Each stitch in a wale is suspended from the one above it.
Like weaving, knitting is a technique for producing a two-dimensional fabric from a one-dimensional yarn or thread. In weaving, threads are always straight, running parallel either lengthwise (warp threads) or crosswise (weft threads). By contrast, the yarn in knitted fabrics follows a meandering path (a course), forming symmetric loops (also called bights or stitches) symmetrically above and below the mean path of the yarn. These meandering loops can be stretched easily in different directions, which gives knitting much more elasticity than woven fabrics; depending on the yarn and knitting pattern, knitted garments can stretch as much as 500%. For this reason, knitting was initially developed for garments that must be elastic or stretch in response to the wearer’s motions, such as socks and hosiery. For comparison, woven garments stretch mainly along one direction (the bias) and not very much, unless they are woven from stretchable material such as spandex.Knitted garments are often more form-fitting than woven garments, since their elasticity allows them to follow the body’s curvature closely; by contrast, curvature is introduced into most woven garments only with sewn darts, flares, gussets and gores, the seams of which lower the elasticity of the woven fabric still further. Extra curvature can be introduced into knitted garments without seams, as in the heel of a sock; the effect of darts, flares, etc. can be obtained with short rows or by increasing/decreasingt number of stitches. Thread used in weaving is usually much finer than the yarn used in knitting, which can give the knitted fabric more bulk and less drape than a woven fabric.
If they are not secured, the loops of a knitted course will come undone when their yarn is pulled; this is known as ripping out, unravelling knitting, or humorously, frogging[1]. To secure a stitch, at least one new loop is passed through it. Although the new stitch is itself unsecured (”active” or “live”), it secures the stitch(es) suspended from it. A sequence of stitches in which each stitch suspended from the next is called a wale]To secure the initial stitches of a knitted fabric, a method for casting on is used; to secure the final stitches in a wale, one uses a method of bindng off During knitting, the active stitches are secured mechanically, either from individual hooks (in knitting machines) or from a knitting needle or frame in hand-knitting.


Basic pattern of warp knitting. Parallel white, red and green yarns zigzag lengthwise along the fabric, each loop securing a loop of an adjacent strand from the previous row. Thus, the two central wales in this picture are alternating white-red-white and red-green-red stitches.

Today Post::Chemical Form of Dye| Dye Textiles | Dye | Colour

Chemical Form of Dye Dye Textiles Dye Colour

Group Structural Unit
Nitroso—-R-NoH
Nitro——R-No2
Azo——-RN-NR’
Di-Azo—RN-NRN ‘ = NR”
Tri- Azo—RN- NR’N= NR”N=NR”

Dyes: Dyes are colored, unsaturated organic chemical compounds capable of giving color to a Textile Substrate for dyeing it.

Colour: Colour is the result of and interaction between a chromophore and colour bearing group and light.

To read more about Dye pls visit: Different Dyestaff Used in Fabric Dyeing

Today Post::Weaving=?UTF-8?B?4oCd?=+=?UTF-8?B?4oCd?=Spinning

Weaving and Spinning is related each other. One is impossible except other. Before going to process of weave, we must have to have in our hand some yarn, which I can get from the process of Spinning. So it can be said that "weaving+spinning" is most crucial fact on textile processing. Firstly I will discuss about something of spinning.
The last step of spinning is Ring Spinning. Ring Spinning is a universal system. The process involved in ring spinning is creeling, drafting, twisting, winding, building up and doffing. In normal ring frames, the number of spindles are 400-500, but 1000 delivery i.e. spindle per ring frame is also available. The delivered roving in bobbin from is fed in the creels of the ring frame. The roving are unwound by pulling action and passed through the drafting zone. At the front side of drafting rollers that is front roller, the drafted fibres become twisted and forms yarns. The twist is inserted by the ring and traveler. The traveler rotates by yarn tension and spindle speed. One turn of traveler inserts one twist on the yarn. Delivery package that is yarn bobbin is situated on the spindle. The delivered yarn is wound on the yarn bobbin. Up and down movement of the ring rails f facilitates yarn winding through out the height uniformly on the yarn bobbin.
The spindle speed of the ring frame govern yarn production rate. Normally spindle speed varies from 10000- 20000 r.p.m. the simple production calculation of a ring frame is as follows:
Production per spindle per minute= spindle RPM / yarn TPI
=Yarn delivery in inches per minute.

Now I will tell you something about weaving:

Woven fabrics are produced in the weaving machine. In woven fabrics two series of yarns are observed. The yarns laid in length dire4ction of fabric are called warp yarn and the yarn laid in width direction of fabric is called weft yarn. The warp yarns are also called ends and the weft yarns are also called picks .the warp and weft yarns are bound together by their interlacement called fabric structure. The most common fabric structures are plain and twill for woven fabrics.

Today Post::Textile Mills

In Bangladesh, visiting different Textile Mills it is found that a very few of the industry are conscious about the environmental policies, working environment, remuneration, Effluent Transfer Plant (ETP) etc. It is hopeful news that some of the industries are implementing the facts now. Now let ourselves to know the fact what should have the industries.

1. A Textile Mill should have the basic salary structure for the workers and employee that are decent for them.
2. They should have the Medical Facility for the workers and employee.
3. They should have the working environment where the workers feel ease to work.
4. High temperature (no need in production) should be controlled in every Textile Mills.
5. Effluent Transfer Plant should be constituted to neutralize the toxic chemical mixed water and dyestuffs.
6. Good and easy arrangement for Emergency Exit.
7. Ensuring the stability of the job.
8. Quietly stopping the Labour Violence.

See more about textile click on: http://texarticles.blogspot.com/2009/05/inrtoductory-of-garments-manufacturing.html

Today Post::Knit and Purl Stitches

Knit and purl stitches

In securing the previous stitch in a wale, the next stitch can pass through the previous loop either from below or above. If the former, the stitch is denoted as a knit stitch; if the latter, as a purl stitch. The two stitches are related in that a knit stitch seen from one side of the fabric appears as a purl stitch on the other side.
The two types of stitches have a different visual effect; the knit stitches look like “V”’s stacked vertically, whereas the purl stitches look like a wavy horizontal line across the fabric. Patterns and pictures can be created in knitted fabrics by using knit and purl stitches as “pixels”; however, such pixels are usually rectangular, rather than square, depending on the gauge of the knitting.Individual stitches, or rows of stitches, may be made taller by drawing more yarn into the new loop (an elongated stitch) which is the basis for uneven knittin : a row of tall stitches may alternate with one or more rows of short stitches for an interesting visual effect. Short and tall stitches may also alternate within a row, forming a fish-like oval pattern.


Two courses of red yarn illustrating two basic fabric types. The lower red course is knit into the white row below it and is itself knit on the next row; this produces stockinette stitch. The upper red course is purled into the row below and then is knit, consistent with garter stitch.
In the simplest knitted fabrics, all of the stitches are knit or purl; these fabrics are denoted as stockinette and reverse stockinette, respectively. Vertical stripes (ribbing) are possible by having alternating wales of knit and purl stitches; for example, a common choice is 2×2 ribbing, in which two wales of knit stitches are followed by two wales of purl stitches, etc. Horizontal striping (welting) is also possible, by alternating rows of knit and purl stitches; the simplest of these is garter stitch, so-called because its great elasticity made it well-suited for garters. Checkerboard patterns (basketweave) are also possible, the smallest of which is known as seed stitch: the stitches alternate between knit and purl in every wale and along every row.
Fabrics in which the number of knit and purl stitches are not the same, such as stockinette, have a tendency to curl; by contrast, those in which knit and purl stitches are arranged symmetrically (such as ribbing, garter stitch or seed stitch) tend to lie flat and drape well. Wales of purl stitches have a tendency to recede, whereas those of knit stitches tend to come forward. Thus, the purl wales in ribbing tend to be invisible, since the neighboring knit wales come forward. Conversely, rows of purl stitches tend to form an embossed ridge relative to a row of knit stitches. This is the basis of shadow knitting, in which the appearance of a knitted fabric changes when viewed from different directions.
Typically, a new stitch is passed through a single unsecured (”active”) loop, thus lengthening that wale by one stitch. However, this need not be so; the new loop may be passed through an already secured stitch lower down on the fabric, or even between secured stitches (a dip stitch). Depending on the distance between where the loop is drawn through the fabric and where it is knitted, dip stitches can produce a subtle stippling or long lines across the surface of the fabric, e.g., the lower leaves of a flower. The new loop may also be passed between two stitches in the present row, thus clustering the intervening stitches; this approach is often used to produce a smocking effect in the fabric. The new loop may also be passed through two or more previous stitches, producing a decrease and merging wales together. The merged stitches need not be from the same row; for example, a tuck can be formed by knitting stitches together from two different rows, producing a raised horizontal welt on the fabric.
Not every stitch in a row need be knitted; some may be left as is and knitted on a subsequent row. This is known as slip-stitch knitting. The slipped stitches are naturally longer than the knitted ones; for example, a stitch slipped for one row before knitting would be roughly twice as tall as its knitted counterparts. This can produce interesting visual effects, although the resulting fabric is more rigid, because the slipped stitch “pulls” on its neighbours and is less deformable. Slip-stitch knitting plays an important role in mosaic knitting, an important technique in hand-knitting patterned fabrics; mosaic-knit fabrics tend to be stiffer than patterned fabrics produced by other methods such as Fair-Isle knitting.
In some cases, a stitch may be deliberately left unsecured by a new stitch and its wale allowed to disassemble. This is known as drop-stitch knitting. and produces a vertical ladder of see-through holes in the fabric, corresponding to where the wale had been.


The stitches on the right are right-plaited, whereas the stitches on the left are left-plaited.


Within limits, an arbitrary number of twists may be added to new stitches, whether they be knit or purl. Here, a single twist is illustrated, with left-plaited and right-plaited stitches on the left and right, respectively.

Today Post::Dyestaff Selection in Reactive Dyeing

Dyestuff Selection in Reactive dyeing

The selection of reactive dyestuff for a tri-chromatic or bi-chromatic combination plays a very important role in the performance and reproducibility of reactive dyeing in textile processing. The following points are to be borne in mind, while selecting the dyestuff for a combination shade.
Solubility of individual dyestuff in grams liter without salt (straight) and with salt should be checked prior to dye selection for a combination shade. In a tri-chromatic combination, all the dyes should have almost similar solubility property. The dyestuff that gets affected by the presence of salt would, a) produce tonally different shade, b) produce poor rubbing and wash fast dyeing and c) batch to batch difference in depth and tone would result.
Some important Criteria to be considered while selecting dyestuffs for a tri-chromatic matching

Use of Primary colors:
One should try to use the Basic Colors such as Red, G.Yellow and Blue. The secondary colors should be avoided as far as possible.
The Red’s and Blue’s varies with shade and requirement of fastness properties.
Dyes with similar Exhaustion and Fixation values:
The Reactive dyeing takes place in three steps. viz.,
1. Exhaustion ( primary and secondary)
2. Fixation
3. Wash off
Normally two types of exhaustion take place while dyeing. These are primary and secondary exhaustion.
Primary Exhaustion is the amount of dyestuff migrated on the substrate in the presence of salt. While secondary exhaustion is the total amount of dye migrated on the substrate in the presence of salt and alkali.
While selecting a combination, one has to ensure that the Percentage Exhaustion (PE) and The Percentage Fixation (PF) of dyes should be similar.
In the case of
Reactive ME Dyes PE is 60 to 70%
Reactive HE dyes PE is 70 to 80%
Reactive VS dyes PE is 40 to 50%
If is always preferable to use dyes with PE about 60 to 70%, i.e., ME dyes. Patchy dyeing may occur if peoper care is not taken while using dyes with higher PE, or lower PE.
Dyes With Similar Affinity:
Generally the dyes are classified as Low, Medium, High and Very High affinity dyes.
For Exhaust dyeing, High and very high affinity dyes and preferred. Where as low affinity dyes are used in continuous dyeing.

Today Post::Introductory of Garments Manufacturing

Garments Manufacturing

The processing steps and techniques involved in the manufacturing garments for the large scale of production in industrial basis for business purposes is called garments manufacturing technology. Garments factories are classified according to their product types are as follows:

Garments Factory—-1. Woven Garment Factory.
2. Knit Garments factory
3. sweater Garments Factory

Garments Manufacturing Process

Stepwise garments manufacturing sequence on industrial basis is given below:

Design / Sketch

Pattern Design

Sample Making

Production Pattern

Grading

Marker Making

Spreading

Cutting

Sorting/Bundling

Sewing/Assembling

Inspection

Pressing/ Finishing

Final Inspection

Packing

Despatch

Today Post::Garments Production and Textile Export Information

Garments are produced in the garments factories on industrial basis for all the people of a specific country. Bangladesh is one of the garments producing & exporting country in the world market. At present, there are about 4500 garments factories running in Bangladesh. Growth of garments factories started in Bangladesh around 1980. Around 1980, garment production & export business was almost unknown to us. Foreign currency earning through garments export from Bangladesh started in 1980-81 with starting figure US $ 3.24 million which was not countable in percentage of the total national foreign currency earnings. Afterwards, tremendous growth of garment factory, garment productions and garments export, the percentage of foreign currency earnings through garments export reached from 0% to around 80% of the national foreign currency earnings in 2007- 2008 financial year.

At present Bangladesh is producing & exporting more than 60item of garments. The most common items are shirt, trouser, jacket, sports wear. T –shirt, Polo shirts, ladies wear, sweater, socks, hats etc. this produced items are exported in USA, Canada, EEC, Japan, Australia, Middle-East and many other countries in the world. Bangladesh is one of the important and competitive garments exporting country in the world market. Cheapest labor cost is the biggest advantage for Bangladeshi garments producers and exporters..

To produce and export garments form these 4500 garments factories about 2000000 people is engaged full time basis. For backward linkage around 20000000 people is needed and for forward linkage about 2000000 people is need. Hence for year to year continuous garment export around 6000000 people is needed. 90% of these huge work forces are illiterate and remaining 10% may be counted for literate. It is a v3ery big challenge for Bangladesh to survive as garment exporter in the world market with that type of man power. But it still remains true that the growth of Bangladesh garments sector is satisfactory.

Today Post::Introductory of Garments Dyeing

Garments Dyeing
Introductory Ideas of Garments Dyeing

Garments dyeing is a new technology for us but it is actually using in the European countries for last 70 years. At first this technology applied on woolen and silk garments but now it is applied on polyester, nylon, acrylic, and also extessivelyu on cotton garments. Popularity of garments dyeing is increasing in France, Italy, Spain, Germany, Canada, North America, Turkey, Israel, South Africa, Japan, USA, and UK etc, Countries.

Normally we dye fibre , yarn, or fabric and then the dyed and finished fabric I used for making garments. In case of garments dyeing, the garments are made from grey fabric, and then the garmens are dyed in required colour and shade. The garments, which are dyed in garments dyeing technique, are as follows:

1. Active wears 2. Jeans Item 3. Panty hose 4. Shirt 5. Slacks 6. Terry Items 7. Dresses
8. Leisure wear 9. Pullover 10. Skirt 11. Socks 12. Sweater 13. Etc.

Today Post::Cotton Fabric Dyeing With Reactive Dyes

Cotton Fabric Dyeing process with Reactive Dyes

Cotton fabric after pre-treatments e.g desizing, scouring & bleaching can be dyed using the following recipe:

Reactive Dyes————————–X%
Sequestering agent—————–0.5 G/L
Wetting agent———————–0.1-0.5 G/L
Ant-creasing agent——————0.5-2.0G/L
Salt————————————10-80 G/L
Soda———————————–2-20G/L
Temperature ————————-60-80 Degree
Dyeing time————————- 60 minute.

When the dyeing is complete, drain-off the dye liquor. Wash he fabric with hot water at 40 degree c & hen with cold water. Again wash the dyed fabric with 1-3 G/L soap or detergent at 60 degree – 80 degree c for at least 10 minutes. Then drain –off the washing liquor. Again wash the dyed fabric with hot water & then with cold water.
Finally, take out the dyed fabrics from the machine, hydroextuct the fabric and dry the fabric passing through stenter m/c any other drying machine.

Today Post::Articles of Spinning, Weaving, Dyeing and Garments

Basic of Textile Engineering! Spinning, Weaving, Dyeing and Garments

In several of Textile Thesis published in different magazine are found the contemporary articles about the modern mechanism and articles about Spinning, Weaving, Dyeing and Garments Technology. But sometime we need to know about the fundamentals of Textile. Very few of the thesis and articles contain it. So I will try my best to provide you the basic of Textile. And of course I will include everything about Textile successively. So let me start now………

Textile Fibre

In Textile industry we have to work with fibre and fibre related components. That means without fibre it's not possible to make a yarn. If yarn is not possible, making fabric and garments are impossible. So it is seen that Fibre is very important. First of all I will give you some basic knowledge about Textile Fibre. Later… I will tell you elaborately in the certain post that is collected from the various thesis and magazine.

Fibres are used to production of Yarn and Fabric called Textile Fibres. It is essential to know that a Textile Fibre must have some definite characteristics. These are-
1. Minimum Length. It should be 100 times of long than its diameter.
2. Strength
3. Elongation and Elasticity
4. Moisture absorbency
5. Tendency to be twisted.
6. Fibre Fineness.

Classification of Textile Fibre:
1. Natural Fibre
2. Man-made Fibre

Natural Fibre are derived from a) Tree i,e, Seed, Leaf, Bast Fibres
b) Animal i,e, Silk, Wool
c) Mineral i,e, Asbestos
d) Metal Fibre i,e, Gold, Silver

Mane-made Fibre are derived from a) Regenerated–Cellulose Base, Protein Base,
Mineral Base.
b) Synthetic—Organic Base (Polyamide, Polyester, Thermoplastic, Hydrocarbons), Inorganic Base

Today Post::Dyeing Machine- Sample

Sample Dyeing Machines:

Sample Dyeing Machine - as the name suggests these machines are made available as sample to the buyer’s needs. These machines are quite popular in the industry. It is successfully applied for dyeing of various types. For example it is used for the atmospheric dyeing of substrates like fabrics, fibres, yarns at heightened liquor ratios either for development or for simulating bulk processing. Some of the types of sample dyeing machine are discussed here in this pages.

The Sample Dyeing Machine that is highlighted here comes with some unique features, that includes:* Latest technology that uses around 16 high temperature glass dye tubes that are interchangeable.* Capacity ranges from 200cc - 2000cc.* Sample holders for fibres, yarns or fabrics are made of stainless steel.* Electronic temperature controller that is digital controlled.* Double Speed agitation.The model featured here is known as the infrared sample dyeing machineModel featured. Some of the very striking features of this model are given here:* State-of-the-art unique touch screen control.* Easy availability of single, double or even triple bath versions

Today Post::Dye and Colors

If white light is spread out by a prism, we can see that it is composed of different colors. Each color corresponds to a different wavelength. The color of a compound depends on the wavelength of light which it absorbs. If a compound does not absorb any visible light it will be colorless. If a compound absorbs light we will perceive the complementary color, because the light which reaches our eyes is missing the wavelengths which have been absorbed.
Color and wavelength
Wavelength of light, nm Color
Complementary color
400-430 Violet green-yellow430-480
blue
yellow
480-49o green-blue
orange
490-510
blue-green
red
510-530
green
purple
530-570
yellow-green
violet
570-580
yellow
blue
580-600
orange
green-blue
600-680
red
blue-green
The ability of a compound to absorb light depends on the presence of certain kinds of structural features called chromophores. “Chromophore” is one of those useful but sloppy words whose meaning depends somewhat on the context.
If we are talking about color, then a chromophore will be an extended conjugated system, particularly one where there are different resonance contributing forms differing in charge distribution.
If there is simply a conjugated system, with nothing but C=C, it takes quite a long chain of conjugated bonds to give a colored system:
H-(CH=CH)n-H
n =
wavelength (nm)
1
180
2
217
3
268
4
310
5
335

However if the chain of double bonds is long enough quite intense colors can result; the colors of carrots and tomatoes result from carotenoids, which have such chromophores.
Similarly, although benzene is colorless (it does not absorb visible light) compounds with fused rings absorb at longer and longer wavelengths. The ultimate is graphite, which contains large sheets of fused rings and is black because it absorbs all wavelengths of visible light.
Much smaller molecules can be colored if they have polar functional groups.
An example is indigo, the dye used in blue jeans.

If you write the various resonance contributing forms you will see that there can easily be separation of charge, with the charge spread over the molecule. Ancient Mediterranean civilizations prized a variant of indigo, obtained from a species of snail. 6,6′-Dibromoindigo or Tyrian purple was so expensive that only royalty could afford it.

Many natural pigments are based on the quinone chromophore,
The parent quinone shown, benzoquinone, is yellow; with larger conjugated systems, and especially with hydroxyl groups to modify the chromophore, they can be bright red.
Cochineal is a pigment obtained from dried female insects which live on a cactus. The pigment is used for food and cosmetics; the principal ingredient is carminic acid, which is a C-glucoside
of a polyhydroxyanthraquinone.

Before the invention of synthetic dyes, it was an important dye for wool and silk. The natural dye consists of the dried bodies of the insects. The insect, and the cactus it feeds on were brought back to the Old World from Mexico, and extensively cultivated. Since cactus species are only found in the New World, both the insect and its food had to be brought back.

The colors of many flowers are based on chemicals with the flavone chromophore or variations of it.
A complicating feature is that the color changes with pH, and the same chemical can be, and is, responsible for the red color of roses and the blue of cornflower; the pigment is cyanidin. This was once attributed to different cytoplasmic pH for the different flowers, but this difference is nowhere near large enough to cause the color change.
Only recently has it been discovered that the actual pigments are aggregates of several cyanin type molecules with metal ions and other pigments. A complication which should be mentioned is that the actual species in the flowers is a glycoside, with a sugar attached to at least one of the hydroxyls. For some of the hydroxyl groups, loss of a proton would give a molecule for which at least some resonance contributing forms would not have a charge on oxygen, although there would still be contributing forms with charge separation. Similar behavior is responsible for the change in color of morning glories as the bright blue of morning becomes purple or pink in the evening as the flower dies and becomes acidic.

Today Post::Warp and Weft Knitting Machines | Types of Knitting Macines

Weft and warp knitting

There are two major varieties of knitting: weft knitting and warp knitting. In the more common weft knitting, the wales are perpendicular to the course of the yarn; however, in warp knitting, the wales and courses run roughly parallel. In weft knitting, the entire fabric may be produced from a single yarn, by adding stitches to each wale in turn, moving across the fabric as in a raster scan.By contrast, in warp knitting, one yarn is required for every wale. Since a typical piece of knitted fabric may have hundreds of wales, warp knitting is typically done by machine, whereas weft knitting is done by both hand and machine. Warp-knitted fabrics such as tricot and milanese are resistant to runs, and are commonly used in lingerie.
Weft-knit fabrics may also be knit with multiple yarns, usually to produce interesting color patterns. The two most common approaches are intarsia and double knitting. In intarsia, the yarns are used in well-segregated regions, e.g., a red apple on a field of green; in that case, the yarns are kept on separate spools and only one is knitted at any time. In the more complex double knitting, two or more yarns alternate repeatedly within one row and all the yarns must be carried along the row, as seen in Fair Isle sweaters. Double knitting can produce two separate knitted fabrics simultaneously, e.g., two socks; however, the two fabrics are usually integrated into one, giving it great warmth and excellent drape.


In the knit stitch on the left, the next (red) loop passes through the previous (white) loop from below, whereas in the purl stitch (right), the next stitch enters from above. Thus, a knit stitch on one side of the fabric appears as a purl stitch on the other, and vice versa.

Today Post::Different dyes used to dyeing the fabric and yarn

Dyeing Fabric is the most common things that every Textile Engineers should have to know. There are many kind of dyes are used to dyeing fabric. Maximum of them are suitable for fabric dye and yarn dyeing.
Dye staffs used to fabric dyeing are:

Direct dyes: These dye staffs are generally sodium salt of sulphonic acid. They have direct affinity to cellulosic fibre. They are water soluble and needs salt addition in the dye bath. Should be applied at alkaline or neutral condition. Poor fastness to wash but cheaper for fabric dyeing.

Basic dyes: These are generallyu ammonium, sulphonium or a uxonium salt. Famous for bright shade during dyeing fabric. Water soluble and application on cotton and other cellulosic fibre and leathers.

Acid dyes: chemically acid dyes belongs to various subclasses such as nitro nitroso, monoazo, diazo, xanthance azine, quinoline, anthraquinone etc. they are water soluble and have affinity to wool, silk and nylon fibres to dyeing. They are applied to the fibres through neutral or acid dye bath.

Mordant dyes: they are the oldest natural dyes. They have no affinity to textiles but can be applied to cellulose or protein fibres in order to dyeing fabric when they have been mordented previously with metallic salt. These dye staffs are capable of combining with metallic oxides to form insoluble colour on the fibre .

Sulpher dyes: These are complex organic compounds containing sulphur. They are insoluble in water but sluble under reduced condition . they are usually applied cotton for cheaper shades, have high wet fastness but poor light fastness during dyeing fabric.

Azoic dyes: these are not ready made dyes. Fibres are firstly impregnated with a coupling component like bita nepthol and then combined with a diazotized base to producer insoluble dye staffs into the fibre. Their main use on cotton but also can be used to dyeing wool silk and fur.

Vat dyes: they are very fast color on cotton and insoluble in water. They are reduced by strong reducing agent to pr9oduce leuco vat and at this stage they are soluble in water. After impregnation they are again oxidized to their original insoluble form.

Reactive dyes: these dye staffs directly combinds with cellulose by chemical bonding i.e. covalent bonds are produced. They have excellent wash fastness. Mainly used on cotton dyeing . can also be applied on wool, silk and nylin dyeing. Dyeing is carried out in an alkine bath.

Disperse dyes: these dye staffs are very suitable for synthetic fibres for example polyester, nylon, acrylic, cellulosic acetate, etc. high temperature dyeing methods are suitable for these dye staffs but carrier dyeing method can also be applied.

Today Post::Dyeing Fibres or Fiber Dyeing | Using Basic Dye for Cotton Fiber Dyeing | Mordanting & Fixing | Dyeing Textiles

To know more about dye Dyeing and Related Topics please follow this link:http://http://texarticles.blogspot.com/2009_05_01_archive.html

Cellulose Fiber has no affinity for basic dyes. So chemicals are applied (Mordanting Process) to create affinity in Cotton Fibre Dyeing.
Sequence is as follows:

1. Mordanting and Fixing:
Tertaremetic Acid
Fibre+ Tannic Acid Fixation Tannin Mordanting Cellulose.

Alternating synthetic mordents may be used.

Mordanting Fixing
Tannic Acid=4% Tertaremetic Acid=2%
M : L= 1:20 M : L = 1:20
Time = 2 hrs Time = 30 Min
Temp = Boiling Temp= Boiling

2. Dyeing:

Dye→1%
M : L→ 1 : 20
Time → 1 hrs
Temperature → above 70◦

Today Post::To knit | Types of Knitting Machines

To know more about Knit just follow this link: http://texarticles.blogspot.com/2009/06/knit-and-purl-stitches.html
To knit means knitting. And the knitting is done by using two machine named Warp Knitting Machine and Weft Knitting Machine. To knit a fabric the weft knitting machine is used exclusively. Now I will discuss something about weft knitting machine.

Weft Knitting Machine:
The knitting machine in which the loops are produced in a horizontal direction and each loop in horizontal direction is made from a single yarn is called Weft Knitting Machine. Here usually latch needle is used along with feeder.

Types of Weft Knitting Machine:
1. Fabric Machine: - In fabric machine fabric is knitted in a continuous, uninterrupted length of constant width. It is also known as yard goods or piece goods machine.

2. Garments Length Machine: - Garments length Machine which has an additional garments control mechanism to co-ordinate the knitting action in the production of garments structured repeat sequence in a wale direction.

Weft Knitting Machine according to Machine Design and Needle Bed:

Flat Machine: a) V-bed flat m/c
b) Flat bed purl m/c
c) Domestic Single Bed Flat m/c
d) Unidirectional multi-carriage m/c

Circular Machine: a) Single Needle Bed M/c
b) Two Needle Bed M/c

3. Straight Bar M/c: a) Single Needle Bed M/c
b) Two Needle Bed M/c

Today Post::knitting | To Knit

Knitting is a method by which thread or yarn may be turned into cloth. Knitting consists of loops called stitches pulled through each other. The active stitches are held on a needle until another loop can be passed through them.
Knitting may be done by hand or by machine. By hand, there are numerous styles and methods. Flat knitting, which can be done on two straight needles or a circular needle, produces a length of cloth, while circular knitting, which is done on circular or double-pointed needles, produces a seamless tube.
Different yarns and knitting needles may be used to achieve different end products by giving the final piece a different colour, texture, weight, or integrity. Using needles of varying sharpness and thickness as well as different varieties of yarn adds to the effect.

Today Post::Different Dyestuff used in Fabric Dyeing

Different types of dyestuff used in Fabric Dyeing

Direct Dyes: These dye staffs are generally sodium salt of sulphonic acid. They have direct affinity to cellulosic fibre. They are water soluble and need salt addition in the dye bath should be applied at alkaline or neutral condition. Poor fastness to wash but cheaper.
Basic Dyes: These are generally ammonium, sulphonium or auxonium salt famous for bright shade. Water soluble and application on cotton and other cellulosic fibre and leathers.
Acid dyes: chemically acid dyes belongs to various to various sub classes such as nitro-nitroso, monoazo, diazo, xanthane azine, quinoline, anthraquinone etc. they are water soluble and have affinity to wool, silk and nylon fibres. They are applied to the fibres through neutral of acid dye bath.
Mordant Dyes: they are the oldest natural dyes. They have no affinity to textiles but can be applied to cellulose or protein fibres when they have been mordented previously with metallic salt. These dye staffs are capable of combining with metallic oxides to form insoluble color on the fibre.
Sulpher Dyes: these are complex organic compounds containing sulpher. They are insoluble in water but soluble under reduced condition. They are usually applied at cotton for cheaper shades, have high wet fastness but poor light fastness.
Azoic Dyes; these are not readymade dyes. Fibres are firstly impregnated with a coupling component like bita nepthol and then combined with a diazotized base to produce insoluble dye staffs into the fibre. Their main use on cotton but also can be dyed silk and fur.
Vat Dyes: They are very fast color on cotton and insoluble in water. They are reduced by strong reducing agent to produce leuco-vat and at this stage they are soluble in water. After impregnation they are again oxidized to their original insoluble form.
Reactive Dyes: These dye staffs directly combines with cellulose by chemical bonding I,e covalent bonds are produced. They have excellent wash fastness. Mainly used on cotton, can also be applied on wool, silk & nylon. Dyeing is carried out into a neutral bath but fixation is carried out in an alkynes bath.
Disperse Dyes: These dye staffs are very suitable for synthetic fibres for example polyester, nylon, acrylic, cellulose acetate, etc. High temperature dyeing methods are suitable for these dye staffs but carrier dyeing method can also be applied.

Today Post::What should i do if batch to batch shade variation happen in Reactive Dyes?

I am getting batch-to-batch shade variation (color variation) for the same reactive shade, in Soft Flow dyeing machine. I am using the same manufacturer's dyes and chemicals and almost same quality of fabric. What are the reasons and how to avoid it?

Answer: Batch to batch shade variation is a general phenomena noticed almost everywhere in dye houses. There are so many factors that affect a particular dyeing operation. Please make the following checks; I hope you can eliminate 90 to 100% of the above problem.
Phase-1: Preparatory Stage.
Check the batch weight exactly for all batches. Find the exact GSM of the greige fabric and note down on your job card.
After Scouring, Bleaching and neutralization, before dyeing, take a sample, dry it, condition it and check the GSM.
Note down the difference in percentage as Scouring and bleaching loss on the job card. Compare this loss% between each batch. It should not deviate more than 2 to 3%.
If deviation is there then the following may be the reasons:
Material to Liquor Ratio difference during scouring/bleaching.
Process timing difference
Temperature may be kept high or low.
Low or better quality of grease material, i.e. Higher staple length good quality fiber loses less weight rather than the poor quality short staple length fiber.
Alkali and Scouring auxiliaries' concentration or quality may have changed.
Quality of water would have changed. Check for hardness, TDS and pH of water used in each batch.
Check the whiteness index of the RFD fabric and note on the Job card.
Check the absorbency of RFD fabric and note on the job card. Let the test results be noted in terms of seconds.
Check the remaining Core alkali in the fabric and the fabric pH.
Check for residual Peroxide on the fabric before dyeing.

Phase-2: Dyeing Stage.
Check the quality of input materials.
Dyestuff concentration to be checked drum to drum.
Check the quality of sequestering agents.
Check the quality of water – pH, hardness and turbidity. Check personally while weighing the dyes and chemicals
Check personally while dissolving the dyestuff, filtering the dyestuff solution and adding in to the dye bath in to the machine.
Check the quality of Salt. Find out in advance how much hardness is increased in the dye bath due to salt addition.
Counter the hardness due to salt with proper dosage of a good quality-sequestering agent.
Check the quality of Soda Ash. Check for purity percentage.
Allow the same number of minutes or hours to run dyeing with salt alone – e.g. if the first batch – salt addition is done for exactly 30 minutes and after complete addition of salt, if the machine was allowed to run for 30 minutes, before injecting the soda solution, please follow the same procedure. It has its own effect in exhaustion percentage.
Similarly inject the soda in to the machine for the same length of time the first batch was done. If injection time for the first batch was 30 minutes, do it for all subsequent batches for 30 minutes.
Allow running the batch for the same length of time in soda before raising temperature. If it is 20 minutes. Follow the same procedure for all batches.
Steam Raising time – if 60°C is reached in 20 minutes for the first batch – do it for 20 minutes for all batches Run at Specified temperature for the same timings for all batches.
Cheque the pH of the dye bath every 30 minutes from the starting of dyeing and note it the job card. After the final addition of Soda ash the pH should be 11 to 11.2. A well-calibrated good quality pH meter will aid you in this job.
Record the final pH of dye bath after every 30 minutes.
Maintain the water level same throughout the dyeing operation and make sure that your are monitoring the level batch to batch.
Phase-3: Finishing:
Not only the preparation and dyeing operations are important, final finishing operation also is very important to avoid batch-to-batch variation.
After draining the dye bath, do one cold wash and hot wash. Cold wash timings and hot wash timings and temperature are also important. Note this in the job card. Do not take this finishing part as unimportant. In fact here also there is every possibility to get shade variation. a. If temperature and timing of each batch are not same the washing off will also not be the same. Please maintain it.
Neutralize with Acetic acid. The quality of Acetic acid should be checked every time you get fresh lots.
Neutralize with the same quantity of accurately weighed Acetic acid volume. The final pH always determines the tone of the shade. So quality of Acetic acid, quantity of acetic acid and the treatment time are all-important and they should be identical between batches.
Soaping:
Use good Quality Anionic Soap such as Lissopol D of ICI.
Before adding the soap in to the bath, fill the machine with adequate volume of water, run blank for 5 minutes, take out some water and check for TDS. Let the TDS be not more than 100ppm of original water i.e. before entering in to the machine.
If higher TDS observed is say 1000 ppm higher than original water, then it is understood that there is still the high residual salt present in the fabric.
The higher residual salt and soap at higher temperature of say 80° to 90°C would strip off the reactive dyestuffs from the fabric, instead of removing the infixed dyestuff from the surface.
More over the properly not removed salt would result in a harsh feel of the finished fabric.
Higher dosages may sometimes cause white patches.
Maintain the timing, temperature; water level and dosage of soap, same for all soaping processes.
Check the Final pH of the fabric; let it be slightly acidic.
But in acidic pH condition the fabric should not be allowed to kept wet for long durations of say one day or two days, because there is every possibility of formation of fungus over the processed material that not only changes tone but also impairs the strength of fibers.
Final cationic fixing operation: Due to the presence of free formaldehyde in different dosages between manufacturers, the final shade's tone changes to bluer or yellowier side. Select the best product and adhere to it. Do not change this product frequently for small cost benefits.
Final Cationic Softener Treatment: During this phase also there is every possibility of change in tone, depth and light fastness of the final product. Purchase the best product and maintain the same for all your production processes.
Finally the drying temperature. Same temperature and duration of exposure of the fabric is a must. Over dried fabric and under dried fabric will show a lot of shade variation
Machinery Problems for Shade variation:
Rope length should be maintained almost the same in all the loops.
Ensure that in each batch the fabric rope passes through the nozzle of the machine the same number of times during the actual dyeing process.
A change in rope speed - depending on the batch size may be necessary to do this.
Use the same standard program procedures for each batch.
Clean the filter for each batch.
If nozzle diameter can be adjusted in your machine, keep the same diameter for getting the reproducibility.

Today Post::Spinning Introductory Articles of Process

Introductory Ideas of Yarn—Spinning.

Yarn may be defined as the assembling of Textile Fibres or Filaments into a continuous strand by twisting which have the textile characteristics. A yarn should have good tensile strength and high quality. I will discuss later about the characteristics what should have a Yarn.

Types of Yarn:
Yarn can be classified according to—
a) Length of fibre-1.Spun yarn- Short staple
-Long staple.
2. Filament yarn—Mono Filament
–Multi Filament.
b) No. of Strand –a) single yarn
b) Folded or double yarn
c) Cable yarn
c) Spinning System—a) Rotor yarn
b) Ring yarn
c) Worsted yarn
d)Woolen Yarn
d) Process Sequence—a) Carded Yarn
b) Combed Yarn

Count of Yarn:
The count of a yarn is a numerical expression which defines its fineness. It also indicates the mass per unit length or the length per unit mass of yarn.

Cotton Yarn Processing: To produce yarns from staple fibres, a wide range of machines are needed. The sequence is given below…….
Flowchart for Combed Yarn

Processing Machine————-Output
Blow room—————-Lap
Carding———————Carded Sliver
Pre-comb Drawing——-Pre-comb Drawn Sliver
Super Lap Former———-Mini Lap
Comber———————-Combed Sliver
Post comb drawing———Post comb drawn Sliver
Speed frame/ Simplex——-Roving
Ring Frame—————-yarn
Winding ————————Yarn in Large package