Anúncio

Fabric faults

Lecturer em National Institute of Textile Engineering and Research
18 de Nov de 2020
Fabric faults
Fabric faults
Fabric faults
Fabric faults
Anúncio
Fabric faults
Fabric faults
Fabric faults
Fabric faults
Fabric faults
Anúncio
Fabric faults
Fabric faults
Fabric faults
Fabric faults
Fabric faults
Anúncio
Fabric faults
Próximos SlideShares
Yarn faults , causes and its remediesYarn faults , causes and its remedies
Carregando em ... 3
1 de 15
Anúncio

Mais conteúdo relacionado

Anúncio
Anúncio

Fabric faults

  1. Fabric Faults/Defects Definition of defect i. An imperfection that impairs worth or utility. ii. Want or absence of something necessary for completeness or perfection. iii. A fault that spoils the material. Fabric defects: A fabric defect is any abnormality in the fabric that hinders its acceptability by the consumer. Fabric is produced with interlacement of warp and weft yarn or loop formation of yarn. During manufacturing of fabric various types of defects occur in fabric. Some fabric faults are visible and some faults are invisible. Faults or defects in fabric may be result from the following reasons. They are:  Defects resulting from faulty yarn  Faulty weaving/knitting process  Incorrect dyeing and finishing processes Some common fabric defects: Some common defects of woven, knitted and terry/pile fabrics are listed here. Woven fabric defects:  Barre  Coarse ends or picks  Temple mark  Thick and thin place  Bad selvedge  Broken ends or warp  Broken picks or weft  Loose warp  Loose weft or snarl  Double end  Tight end  Float of warp  Wrong end color  Crack  Float  Fly waste  Knots  Reed mark  Slack end  Slough off  Slubs  Miss pick  Double pick  Weft bar  Ball  Hole  Oil spot  Soiled/Oily filling  Tails out Knitted Fabric defects:  Barreness  Birds eye  Broken pattern  Cloth run out  Skip stitch  Dropped stitches  End out  Missing yarn  Mixed yarn  Needle line/mark  Press off stitches  Miss draw
  2. Terry Fabric defects:  Broken pattern due to defective piles  Pile less spot  Uneven or loose piles Some processing defects that are found in fabric: Bow/skew, color out, doctor streak, dye stain, sanforize pucker, seam impression, scrimp. Woven fabric faults, causes and their remedies: SLUB Bad or defective selvedge: Bad selvedge in woven fabrics due to the faulty weaving. Here, warp ends being set too far apart for the thickness of the yarn or in finished fabric. Coloured flecks: Presence of coloured foreign matter in the yarn. Causes: Cotton fibres getting contaminated during the ginning stage with leaves, immature fibre, yellow fibre, etc. Mending: Coloured portion is removed from the yarn with a plucker. The resultant bare patch can be corrected by combing with metallic comb. Knots: Knot is a fastening made by tying together the ends of yarn. Causes: Thread breaks during process of winding, warping, sizing or weaving. Mending: Non Mendable.
  3. Slub: Slub is a bunch of yarn having less twist or no twist and has a wider diameter compared to normal spun yarn. Causes:  Improper carding/combing.  Broken tooth in the chain of gear system. Mending: The slub should be cut with the clipper from both the ends. The resultant bare patch can be corrected by combing with a metallic comb or by insertion of a separate thread with the help of fine needle. Broken pattern: A broken pattern is the non continuity of a weave/ design/ pattern. Causes:  Wrong drawing in of threads.  Incorrect shedding. Mending: Non Mendable. Broken ends woven in a bunch: This defect is caused by a bunch of broken ends woven into the fabric. Cause: Failure of the weaver in attending the warp breaks properly. Mending: The broken ends woven in a bunch can be removed by using a plucker and the resulting loose ends should be cut with clipper. As a result, a bare patch occurs and combing in both directions with a metallic comb can fill this up. Double end: When two or more ends gets woven as one. This defect is characterized by a thick bar running parallel to the warp. Causes: Wrong drawing, taking more ends in heald eye. Mending: This fault can be corrected by pulling out the extra end with the help of needle. A bare patch is formed and can be filled by combing in both directions with the help of metallic comb.
  4. Float: Float is the improper interlacement of warp and weft threads over a certain area. Causes:  Improper sizing (ends sticking).  Broken end entangling with the other ends. Mending: Only minor floats can be rectified. The floating threads are cut with a clipper. Combing in both direction rectifies the resultant patch. Gout: Gout is a foreign matter accidently woven into the fabric. Causes:  Improper loom cleaning.  Unclean environment. Mending: The extra foreign matter can be pulled out with a plucker. Combing in both direction rectifies the resultant patch. Hole/Cut/Tear: Causes:  Sharp edges on cloth roll.  Hard substance between layers of fabric in cloth roll.  Course temples used for fine fabric.  During removal of hard particles like, Iron particles woven in the cloth. Mending: Non mendable. Missing ends: The fabric is characterised by a gap, parallel to the warp. The number of ends missing may be one or more. Causes:  Loom not equipped with warp stop motion.  Dirty drop wires or accumulation of lint may prevent their dropping.  In electric warp stop motion, the electric bars are dirty or corroded. Mending: When there are only two adjacent ends missing, the fault can be rectified by combing in both directions using a metallic comb. This may fill the bare patch formed due to missing ends.
  5. Missing Picks: A narrow streak running parallel with weft threads caused due to absence of weft. Causes:  Faulty let-off and take-up motion.  Faulty weft-stop motion.  Fell of the cloth not adjusted after loom stoppage for mending. Mending: When there are only two adjacent picks missing, the fault can be rectified by combing in both directions using a metallic comb. This may fill the bare patch formed due to missing ends. Stitches: A Single thread float. Causes:  Two adjacent ends sticking together during shedding for a brief period of time.  In case of synthetic yarns, ends sticking together due to static charge during weaving. Mending: Stitches are cut with a clipper from both the ends. Combing in both the directions with the help of a metallic comb may rectify the resultant bare patch formed. Untrimmed loose threads: Any hanging threads on the face of the fabrics are termed as loose threads. Cause: Tail ends not trimmed after piecing up. Mending: These defects can be easily rectified with the help of clipper. Weft bar: An unwanted bar, running across the full width of a piece which differs in appearance from the adjacent normal fabric. Causes:  Difference in count, twist, colour, lustre.  Faulty let-off and take-up motion. Mending: Non mendable.
  6. Lashing in: An extra piece of yarn woven into the fabric in the area of the selvedge. Causes:  Defective setting of the shuttle box.  Early or late picking.  In case of auto loom, weft cutters worn out or not set properly Mending: This defect can be corrected by pulling out the extra pick from the selvedge end, which can be clipped with the help of clipper. A bare patch is formed and can be filled by combing in both directions with the help of metallic comb. Oil or Other Stain: These are spot defects of oil, rust, grease or other stains found in the fabric. Causes:  Improper oiling/greasing of looms.  Oil stained Take up roller. Mending:  Keep the stained portion of the fabric over an absorbent pad. Apply the stain remover, wetting the stain and surrounding portion thoroughly.  Rub gently to quicken the penetration of the stain remover.  Rubbing should be done towards the centre of stain to avoid spreading. Oily ends: These are oily warp ends. Causes:  Improper handling and storage of material in spinning department.  Oil-contaminated guides and oily hands during process of warping.  Improper handling of warp beams. Mending:  Keep the stained portion of the fabric over an absorbent pad. Apply the stain remover, wetting the stain and surrounding portion thoroughly.  Rub gently to quicken the penetration of the stain remover.  Rubbing should be done towards the centre of stain to avoid spreading.
  7. Slough off: A slough-off is a bunch of weft woven into the fabric. Causes:  Improper winding of the yarn onto the weft pirn.  Improper shape and size of the pirn.  Harsh picking. Mending: The bulk yarn can be pulled out by means of plucker. Combing in both direction with help of mettalic comb can fill up the resultant bare patch. Reed marks: A warp way crack caused by a damaged or defective reed. Causes: Defective or damaged reed. Mending: Non mendable. Local distortion: A Distortion occurs when there is displacement of warp and/or weft threads from their normal position. Causes:  The emery roll is worn out.  In filament fabric having low reed picks. Mending: This defect can be corrected by combing in both directions using a metallic comb.
  8. Standard Commercial Fabric Based on Plain weave: Georgette: Georgette is a sheer, light-weight, dull-finished crepe fabric named after the 20th early century of French dressmaker “Georgette de la Plante”. It is originally made from silk but now often is made from manufactured filament yarns. Georgette is made with highly twisted yarns. Its characteristic crinkly surface is created by alternating S and Z-twist yarns in both warp and weft direction. Georgette is made in solid colors and prints and is used for blouses, dresses, evening gowns, saris, and trimmings. It is springier and less lustrous than the closely related chiffon. Chiffon: It is made from fine, highly twisted filament yarns. Because of the tightly twisted crepe yarns, chiffon has excellent drape, very light weight and relatively durable although delicate in appearance. It can be printed or in solid color. It is originally made from silk but now often is made from manufactured filament yarns. Sheer evening dresses, blouses, lingerie and other dressy apparel are made from this fabric. Chiffon is most commonly used to weave sarees, dresses and scarves. Voile: Voile is a soft, sheer fabric, usually made of 100% cotton or cotton blended with linen or polyester. The fabric is made with high twist or voile twist spun yarns that may be combed or worsted. It is a soft fabric with somewhat lower fabric count and has a distinctive two ply warp and good drapability. It can be printed or in solid color. Voile was originally a cotton or wool fabric but now available with many fiber contents. Because of its light weight, the fabric is mostly used in soft furnishing. In tropical climates, voile is used for window treatments and mosquito nets. Generally, 50 counts of yarns, in 60-64 per inch at warp and weft are used. Chambray: It is a plain weave fabric usually of cotton, rayon or blended with polyester. Usually Chambray has white yarns in the weft direction and colored yarns in the warp direction. This type of fabric is both fine and dense, and it is similar to denim in many ways. However, a different weaving pattern is used to make chambray, and as a result, this type of fabric is significantly lighter and more breathable than denim. Poplin: Poplin is a bottom weight rib weave (heavy weight ribbed fabrics) is usually made from cotton or cotton blends, polyester/cotton blends are mostly used. It is a medium to heavy weight, unbalanced, plain weave, spun yarn fabric. The weft yarns are coarser than the warp yarns. A specification of poplin fabric is shown below:
  9. Fabric construction: 14′s/2 ×60′s 60×14 Oxford: It is usually a (2×1) or (3×2) basket weave. It is most common as a (2×1) half basket weave. It may have a yarn dyed warp and white weft and be called oxford chambray. Oxford looks like a balanced fabric because the warp yarns are finer and have higher twist than the weft. Because of soft yarns and loose weave, yarn slippage may occur. Oxford fabrics are medium weight, soft, porous and lustrous. It is often made of cotton or cotton blends, that is used for shirts. Frequently it is made with narrow colored stripes in the warp or a colored warp. Fabric construction: 30′s ×20′s 72×68 or, Fabric construction: 40′s/2 ×40′s/2 60×68 Canvas: It is a heavy, firm, strong fabric made of cotton or acrylic and used for awnings, slip covers, shoe fabrics, tarpaulins and boat covers. It is produced in many grades and qualities. It may have a soft or firm hand. It is made in plain or basket weave. Canvas is smoother, compact and usually have an uneven weave pattern. It is tightly woven and very stiff plain weave fabrics made of even yarn for industrial uses. Because of the tight weave, these fabrics are often used for outdoor purposes. It is made with single or ply yarns. Different types of canvas relate to the number of ply and which yarns (warp/weft) are plied. Fabric construction: 10′s ×10′s 72×42 or Fabric construction: 20′s × 16′s 100×50 Gauge: It is a sheer, light weight, low count, plain weave balanced fabric made of spun yarns. It is often cotton, rayon or a blend of these fibres. Gauge with a higher count than these cheese cloth, is used in theatrical costumes and medical dressings. Buckram: It is heavily sized plain weave fabric to serve as stiffening fabrics. Buckram is a heavy, very stiff spun yarn fabric converted from gray goods with adhesives. It is used as interlining to stiffen the required parts of a fabrics. Based on Twill weave: Denim: Very strong cotton fabric generally, it is 2/1 or 3/1 warp faced twill fabric. The warp yarns are mainly indigo or blue or may yellow or black colors and the weft yarn is in white color. The face side of the fabric is blue, yellow or black to look at, and the back side shows bluish or grey. Denim fabric is used in making garments of
  10. laborers, overall, work wear, and drapery. The specification of a denim fabric is shown below: Fabric construction: 7′s to 16′s ×8′s to 23′s 60×36 to 72×44 Drill: It is very strong cotton warp faced twill fabric. It is a densely woven 2/1 or 3/1 fabric produced from carded yarn. The drill fabric is to some extent like denim fabric. It is used in various works in the form of grey, bleached, dyed, or printed, such as: work cloth, pocketing, lining of shoe, book binding, corset, as coated fabric backing, as industrial fabric etc. The specification of a drill fabric is given below: Fabric construction: 14 tex×16 tex 50×32 (per cm) Jeans: It is mainly warp faced twill fabric, made with carded cotton yarn, lighter than drill fabric and also the twill lines are very fine. The twill lines are stretched from the right side of the lower end to the left side of the upper end. In some cases, shadow stripes are also made using the yarn of “S” twist and “Z” twist. These fabrics are generally solid and printed and sometimes they are mercerized. Jean fabrics are used in sportswear, work wear, uniforms of doctors and nurses, kid’s play suits, and industrial work. The specification of a jeans fabric is as follows: Fabric construction: 30 tex×30 tex 36×26 (per cm) Gabardine: It is a warp faced fabric, made mostly in 2/2 twill, as a result the twill lines are clearly visible and 2/1 twill is made in the lower quality gabardine fabrics. The number of warp yarn used per inch is almost double the number of weft yarn. Carded or combed, single or plied yarns are used which is made from the fibre or the mixture of worsted, cotton, silk, rayon etc. Gabardine fabric is used in making suits for men’s, ladies and the kids; also in making of uniforms, sportswear, raincoats, etc. The specification of gabardine fabric is given below: Fine cotton gabardine: 15/2 tex×15/2 tex 64×42 (per cm) Lower quality gabardine: 30/2 tex×30 tex 43×30 (per cm) Seersucker fabric: Cotton fabric with crinkled length-way stripes caused by differential shrinkage. True seersucker is generated by differential warp tensions but finishing treatments can produce a similar effects. Used for blouses, shirts, dresses.
  11. Some fabric images are given below: Georgette Chiffon Voile Chambray Poplin Oxford Canvas Gauge Buckram
  12. Denim Drill Jeans Gabardine Seer-sucker
  13. Clothing Comfort The term “Comfort” is being mentioned as the absence of unpleasantness or a natural state compared to more active state of pleasure. The most important factor affecting comfort in clothing is the movement of heat and water vapor through a garment i.e., balanced process of heat exchange between the human body, the clothing system and the environment. Clothing comfort depends on  Thermal factors (heat transfer)  Sensorial factors (touching, hand-feel etc.)  Movement of body parts  Social status and conditions  Psychological factors (aesthetic sense)  Functional factors (bullet-proof jacket, firefighter dress etc.) Factors determining clothing comfort  External (Ambient temperature, Wind speed, Moisture in environment, Globe temperature, Cultural, Overall environment)  Internal (Metabolic rate, Level of activities, Health position, Psychological situation) Physical and psychological (aesthetic) aspects of comfort: Comfort is always depend on physiological effects of such climatic variables of temperature, relative humidity and air movement of a body situated in a particular condition and also clothing factors, particularly fabric geometry, pore volume and enclosed air content etc. Comfortability is both subjective and physical. The movement of heat, moisture and air through a fabric are the major factors governing comfort but some of the subjective factors such as size, fit and aesthetic behavior (softness, handle and drape) obviously are very important. In addition, other factors such as the generation of static electricity and the control of noise are closely connected with apparel use. In examining the comfort behavior of textiles, it is necessary to include some consideration of factors that are not measured by physical tests and may be subjective in that two people may disagree about the level of comfort of the same fabric. These aesthetic factors include properties such as softness, handle, drape and
  14. similar properties and may also include properties such as color, style, fashion compatibility and other similar characteristics. There can be innumerable psychological aspects that are responsible for clothing discomfort. However, according to Prof. Lubos Hes's studies, the following components have a lasting effect:  Economical aspects - resources, technology of objects manufactured, skills, political system  Historical aspects - using products made of natural materials, tradition, lifestyle, fashion  Cultural aspects - religion, habit, customs  Social aspects - age, qualification, social status or rank in the class  Individual and group aspects - effects of fashion, trends, styles, colors, personal preferences etc. Since psychological factors can include many more attributes, it becomes extremely difficult to quantify and objectify as to what kind of clothing will be comfortable or not to people. Factors for clothing selection: Social factor: In social factor following things are considered:  The place where person live (Europe/Asia or Urban/Rural area).  Cultural background of person.  Gender  Occupation  Occasion  Social status Economic Factors: In economics factors the important components are economic condition of society, economic status of individual, availability of technology and raw material. If there is change in economic condition of society than it reflects on clothing. We know that the pattern of poor and rich peoples are different. People select clothing depends on affordability and depending on economic status. Environmental Factors: Environmental factors includes environmental conditions like too cold, too hot, raining, chilling wind etc. Cloths are selected to take protection
  15. from extreme environment, unusual places (space or under water). The selection of clothing changes as the environment condition is change. In this factor one person will not use same clothing in different climatic condition. Depending on climatic temperature the garments are broadly divided into two categories: winter wear clothing and summer wear clothing. Physiological factor: This factor includes age, body structure, physiological response of body, activity level etc. The clothing patterns are changes with age of the person due to physiological and psychological changes with time. Otherwise in fabric selection client satisfaction, color, style, durability, suitability, after care condition are also considered. *****END*****
Anúncio