Introduction of a Needle | Specifications of Needle

The typical “European” specifications for a needle includes a word, a number (usually a four digit number) and a final combination of letters and numbers. For example: Vota 78.60 G.02 The capital letter at the beginning of the word ( “V”), identifies the origin of the needle (obtained from a wire, pressed or die-cut), the type, the number of butts and the type of tail. The other capital letters have a very precise meaning, except for the vowels “e” and “a” which are added to make the word pronounceable, and indicate the shape and the height of the butt, the eventual existence of a groove and its size, the length of the tail and some other features of the

needle.

Neddle

The next group of numbers identifies the needle according to the length and the gauge. The first part indicates the whole length rounded off to the mm (in our case that makes 78 mm); the second part indicates the gauge of the needle in hundredths of millimetres (in our case the gauge of the needle is equal to 0.60 mm).

The final group of letters and numbers has to be read as follows. The first capital letter indicates the needle manufacturer (For example Z for Torrington, E for Exeltor, G for Groz-Beckert). The next number is used to distinguish a specific needle among all the needles produced by the same manufacturer.

The next letter refers to some particular features of the needle: for some needles an “A” indicates that the latch has been fixed with an angular pressed pin while an “R” means that the latch has been fixed with a straight pressed pin. For other needles, the latch fixing method is indicated by a “0” before the last number. A “0” indicates that the latch has been fixed with a standard pressed pin; no “0” means that the latch has been fixed with a screw pin.

3D-Weaving | Manufacturing Process of 3D-Weaving | Application of 3DWeaving Fabric

 3D-Weaving

3D-Weaving is a complete new concept in case of weaving. The first method of 3D woven fabric denotes 3 Dimensional fabrics, that is length, width and breadth. In 3 Dimensional fabrics, the thickness is an important criterion. Ordinary fabrics also have length, width and breadth, but in the 3 Dimensional fabrics, the thickness is much more than ordinary fabric. The thickness is achieved by forming multiplayer using multi series of warp and multi series of weft, which are intersecting at regular 90o angle as in usual cloth weaving principle.

It cannot be performed with existing traditional methods and machines. It interlaces a multiple layer warp with multiple horizontal wefts and multiple vertical wefts producing directly shell, solid and tubular types of fully interlaced 3D fabrics with countless cross-sectional profiles.

First demonstrated in 1997, Dual-Directional (D-D) Shedding System is indispensable for performing 3D-weaving. This path breaking development has advanced the technology of weaving to a new dimension for the first time in its more than 27000 years of history.

Manufacturing Technology of 3D-Weaving
Special looms are required to operate the warp threads in 60o angle for weaving 3Dr-3 Directional fabrics. But the 3 Dimensional -3Dm- fabric can be woven by using ordinary loom with usual weaving principle-shedding, picking, beating - by having multi layers of warp and multi layers of weft. Even though the treble cloth with 3 series of warp and weft could be called 3Dm fabrics, in general, minimum 4 series of warp and weft are used in weaving to form several layers, one above the other to get the sufficient thickness resulting into 3 Dimensional fabric.
As per the principle of weft Tapestry fabric, to weave 3Dm fabrics, it is required to use one series of stitching warp and multi series of separating warp as per the number of layers to be formed. 

 As seen from the cross section, the stitching warp passes from top to bottom and bottom to top but all the separating warp lies almost straight and hence the stitching warp takes up more length than the separating warp. Therefore, the stitching warp is brought from a loose tension beam and the entire separating warp is brought from another normal tension beam.

The following points are to be understood from both the cross sections: -

The first layer weft (Face) - shown as “a” - lies between the stitching warp (shown as 1) and first separating warp series (shown as 3).
The second layer of weft (Middle) - shown as “b”- lies between the first and second separating warp series (shown as 3 and 4).

Application of 3D Weaving Fabric
A new method has been developed for the manufacture of bifurcated prosthesis used in medical applications and they are used to replace the defective blood vessels in patients so as to improve blood circulation.

The 3D fabrics have recently entered the medical field. Their specific area of application is in the weaving of vascular prosthesis. Vascular prosthesis are surgically implantable materials. They are used to replace the defective blood vessels in patients so as to improve blood circulation. Conventional types of prosthesis were made from air corps parachute cloth, vignon sailcloth, and other types of clothing materials.

Materials such as nylon, Teflon, orlon, stainless steel, glass, and Dacron polyester fibre have been found to be highly suitable for the manufacture of prosthesis. These materials were found to be significantly stable with regard to resistance to degradation, strength, and were not adversely affected by other factors. Dacron polyester, which has bio-compatibility and high tensile strength, is being used over a period of time as suture thread or artificial ligaments.

Knitting Action of Bearded Needle Simplex Machine

Fig: Knitting action of bearded needle simplex machine

Figure: Shows the knitting action on the front needle bar; an identical sequence occurs afterwards on the back needle bar to complete the machine cycle.

(a) First rise of the needle bar. The knitting action has been completed on the back needle bar for the previous machine cycle. The front sinker/presser bar has withdrawn, leaving the back sinker bar to support the fabric. The guide bars have completed their third swinging movement so that they are now swinging towards the back of the machine, allowing the front needle bar to rise with the back needle bar still near to knock-over and thus helping to hold down the fabric. The front needle bar rises sufficiently to enable the old overlaps under the beards to slide down onto the needle stems.

(b) Return swing, second rise then lowering and pressing. As the guides swing to the back of the machine, the warp ends are wrapped over the needle beards. The front needle bar is now lifted to a higher position so that the new overlaps slip from the beards to a high position on the needle stems. As the front needle bar is lowered to cover the new overlaps, the front sinker presser bar moves to contact and press the beards so that the old overlaps slide onto the closed beards which descend through them.

(c) Completion of landing and knock-over, underlap and third guide bar swing. Whilst the needles descend further to knock-over the old overlaps, the guide bars make their underlap shog behind the front needle bar and then commence their swing towards the front of the machine to allow the back needle bar to rise for the second part of the machine sequence.

Knitting Action of the Crochet Machine

Figure: illustrates the knitting action of a crochet machine:

1. The inlay.Whilst the needle is withdrawn into its trick during knock-over of the previous warp overlap, the weft inlay tube is lowered. As it traverses in an underlap shog, the weft is laid below the level of the needle and on top of the warp thread that extends from its head to the warp guide.

2. Clearing the warp overlap. The weft tube rises slightly on completion of its traverse movement to allow the needle to move out of its trick to clear its old warp overlap.

3. The warp overlap wrap. The warp guide rises between the needles and automatically overlaps from the left, lowering itself again on the right side of its needle.

4. Warp knock-over and underlap. The needle now retires into its trick to knockover the old overlap, whilst the warp guide is cammed under its needle to the start position for its next overlap, thus completing the closed lap pillar. NB:The closed lap is used for the carbine needle but the alternating overlap of the open lap pillar stitch used with the conventional latch and bearded needles gives a more balanced loop structure. Tricot lapping with two guide bars produces a secure fabric which does not unrove.

Importance of Color in Textile

The Importance of Color We Wear
Colors have a demonstrable psychological effect. So, our automatic reaction to colors is so strong. The sight of red means warning and white mean simplicity and respective of title. Military uniforms are intentionally colored to give statement and impose authority. Colors are used in many ways to assert recognition because they are fairly easy to read and understand.

Not all colors are good for any individual because of different skin color tones. The best way to find your personal skin color is to ask a friend who can be objective about your situation. Your friend can “drape” you with big swatches of different colors. The most flattering colors are sometimes the good colors for you. Often, you’ll be surprised that the color you like best is also the best color for you.

Once you know your personal color, practice by understanding their association with seasonable colors (spring, summer, winter, and fall). They can give a set of guidelines for flattering effect of your clothes. You’ll also be able to forecast colors for the next season.

List of Popular Colors and How Our Emotions Respond

BLACK	Severe, mysterious, sophisticated, glum, depressing, deadly
BLUE	Serene, calming, cool, quiet, sleepy, sad
BROWN	Warm, earthy, drab
GRAY	Well-informed, subtle, dignified, gloomy, cold
GREEN	Fresh, successful, loving, greedy, restful, calm.
HOT COLORS	(ie. pink) Wild, sensual, daring, flashy, vulgar
ORANGE	Happy, cheerful, new, motivated, garish, warm.
PINK	Soft, innocent, delicate, feminine, delicious
RED	Alert, warning, sexual, aggressive, energetic, cheerful, angry, vital, exciting
VIOLET	Royal, rich, stately, passionate, subtle but sexy, impressive, alone
WHITE	Clean, pure, young, safe, simple
YELLOW	Sunny, bright, hopeful, optimistic, joyful, clear, positive, alive

It is important to understand that color has three properties. These properties do not affect the meaning of colors unless their appearances have actually changed (ie hot violet, frosted brown)

Color Guidelines According to Seasons

Summer	Think clear, contrast and bold colors.
Fall	Think soft, cool, slightly grayed colors.
Spring	Think bright, fresh and lively colors.
Winter	Think deep, dark and muted colors.

Comparison Between Reactive Dye and Azoics Dye | Comparison Between VatDye and Azoic Dye

Vat Dye vs Azoics Dye 

1. Azoics are economical than Vat dyes.
2. Bright reds , oranges and deep maroon shades are possible in Azoics.
3. Limited Shade range in Azoics.
4. Bright pinks , bright Blue . olive green , green and blacks are not possible in Naphthols.
5. No fear of photodegradation in Naphthols.

6. Rubbing na dlight fastness is inferior in Naphthol dyeing.

7. More Suitable for Tie-dye and space dyeing.

Reactive Dye Vs Azoics Dye
1. Limited shade range in Azoics.

2. Dyeing method is very complex with too many variables in naphtholation , diazotisation and developing baths.
3. Color fastness to Chlorine is better in naphthols.
4. Rubbing and Light fastness are inferior in azoics.
5. Dark and bright reds , maroons and ornages can be produced in azoics which are difficult in reactives.
6. Azoics are suitable for Tie-dye and space dyeing.

Introduction of Naphthol Dyes | Dyeing Procedure of Naphthol Dyes |Roles of Different Chemicals in Naphthol Dyeing

Naphthol dyes are insoluble azo dyestuffs that are produced on the fiber by applying a Naphthol to the fiber and then combining it with a diazotized base or salt at a low temperature to produce an insoluble dye molecule within the fiber. Naphthol dyes are classified as fast dyes, usually slightly cheaper than Vat dyeings; the methods of application are complex and the range of colors limited.

Azoic combinations are still the only class of dye that can produce very deep orange, red, scarlet and Bordeaux shades of excellent light and washing fastness.The pigments produced have bright colors, and include navies and blacks, but there are no greens or bright blues. Crocking fastness varies with shades but washing fastness is equal to Vat dyeings, generally with less light fastness than the Vats.

Naphthols :

The Naphthols are phenols, soluble in alkaline solution and substantive to cotton, particularly in the presence of salt. The anilides of BON acid(beta-oxynaphthoic acid or BON acid) are soluble in dilute NaOH solution and form the corresponding naphtholate ion. These relatively small molecules are of only low to moderate substantivity for cotton, but they diffuse rapidly into the fibres. In general, the higher the substantivity the better the rubbing fastness as less azo pigment forms on the fibre surfaces. The naphtholate ions are always coplanar and preferably have elongated molecular structures. They behave essentially as colorless, low molecular weight direct dyes. The substantivity increases with increase in the molecular size of the naphtholate ion, but the diffusion rate in the fibres and solubility in dilute aqueous alkali decrease. Addition of salt promotes better exhaustion of the bath, more being needed for Naphtols of lower substantivity.

Bases:

These are available as the free amine base or as amine salts such as the hydrochloride.Many of the amines used are simple substituted aniline derivatives with no ionic substituents. The so-called Fast Colour Bases require diazotisation. This usually involves reaction of the primary aromatic amine in acidic solution or dispersion with sodium nitrite, at or below room temperature. Successful diazotisation requires careful weighing of all the chemicals and regard for the supplier’s recommendations. Diazotisation of a primary aromatic amine is often difficult and solutions of diazonium ions are inherently unstable. They undergo decomposition even at low temperature and particularly on exposure to light. Storing prepared diazonium ion solutions is not usually possible.

General Dyeing Procedure of Naphthol Dyes
The application of the naphthols is consists of following steps,

1.Dissolution of the naphthol component.
2.Exhaustion of the naphthol dolution onto the substrate or absorption of the naphtholate ion by the cotton;
3.Removal of excess naphthol from the material by squeezing, partial hydroextraction or brine washing.
4.Diazotization of the base component.
5.Development or treatment with the diazonium ion solution to bring about coupling.
6. Neutralisation ,Soaping at the boil to remove superficial pigment, followed by rinsing and drying.

The process can be carried out in almost any type of dyeing machine determined by the form of the goods.

Dyeing Methods

Precautions in Naphthol Dyeing

1.The alkalinity of the naphthol bath shall not drop below the prescribed limit , otherwise the naphthol may presipitate.

2.Formaldehyde shall not be used when working at more than 50 Deg C or when the material is to be dried after naphthol application.

3.Material shall be protected from water spotting,steam,acid and chlorine fumes , and exposure to sunlight after naphthol application.

4.Use of excess salt in naphthol bath may result into precipitation of the bath.

5.The temperature is very important in base preparation stem , otherwise diazotization may not take place.

6.Sodium acetate must be added to the developing bath just before the use , otherwise base will become unstable due to fall in concentration of HCl.

7.Hydroextraction time must not be too long , which may result into light spots after development.

8.Material shall be rinsed without delay after developing , otherwise the mechanically held excess developing liquor will undergo some decomposition and cause deposition of dark colored spots , which will be difficult to remove.

9.It is important to use sufficient amount of alkali binding agents , otherwise it will result into presipitation of developing bath.

Stripping Process in Naphthol Dyeing
-Treat the dyed material with Non ionic detergent and 3-5 gpl caustic soda at boil for 15 min. cool to 85 degC
-Add 3-5% sod. hydrosulphite for 30-45 min at 85 deg.
-Rinse hot and cold
-Bleach with 1-2 Gpl Available chlorine for 20 min.
-Antichlore and neutralise.
-Soap at Boil for 15-20 min.
-Cold rinse.

Roles of Different Chemicals in Naphthol Dyeing

T.R. Oil :

Wetting agents for naphthol pasting and dissolution and penetrating agent in fiber in naphthol application.

Caustic Soda:

For solubilising of naphthols and keeping proper alkalinity of naphthol bath.

Formaldehyde:

Protective agent of naphthol impreganated material from effect of air.

Salt:

Electrolyte for exhaustion of naphthol during naphtholation and to prevent the desorption of naphthol in the bath during brine rinsing and development phase.

HCl Acid:

Dissolution of base and to produce nitrous acid in diazotization phase.

Sodium Nitrite:

Producing nitrous acid in diazotization process.

Sodium Acetate:

For neutralization of excess HCl in developing bath.

Acetic Acid:

As an alkali binding agent in developing bath.

Non Ionic Dispersing Agent:

To keep the azoic pigments in fine dispersion phase , which are formed by the coupling of free naphthol in developing bath. Also helps in better color fastness during soaping operation.

Fastness Properties on Cotton
Correctly prepared dyeings with azoic combinations on cotton have fastness properties often comparable, or only slightly inferior, to those produced using quinone vat dyes. They complement the vat dyes because of the wide range of orange, red and Bordeaux shades that they provide.

The fastness to washing of azoic combination dyeings on cotton is usually very good to excellent but only after careful elimination of particles of azo pigment loosely adhering to exposed fiber surfaces. Intermediate drying or rinsing of fabric containing the Naphtol, and the soaping of the final dyeing, are key processes ensuring optimum fastness. The same argument applies to rubbing fastness. Deep dyeing that have not been well soaped easily transfer color onto adjacent white fabric, even under conditions of gentle rubbing.

There are two other problems associated with the fastness properties of azoic combinations on cotton. In pale shades, the dyeings often have much reduced light fastness, particularly under humid conditions. Some sensitive azoic combinations also give dyeings of only fair resistance to chlorine and peroxide bleaching.