Yarn Spinning Defects
Appearance: Clustered cotton fiber balls on the fabric surface, similar in size to yarn joints and spun into the yarn. Removing a nep causes the yarn to break or become nearly broken. This defect is common in roving spun from low-grade raw cotton.
Causes: 1) Undissolved dead cotton fiber clusters in raw cotton not completely removed during blowing. 2) Dull needles on the carding cylinder or flat, or improper gauge setting between them, resulting in insufficient carding.
Appearance: Tiny black or dark non-fibrous fragments on the grey fabric of pure cotton or cotton-blended fabrics.
Causes: 1) Cotton seed husks attached to fiber roots or crushed seed particles mixed into raw cotton during ginning. 2) Incomplete removal of cotton seed husks during blowing.
Appearance: Short clustered fiber sections (5-20mm) on warp/weft yarn with larger diameter and fewer twists than normal yarn.
Causes: 1) Uneven fiber density in roving fed during spinning, with small dense spindle-shaped fiber bundles. 2) Improper gripping of fed roving by the top roller and apron of the spinning frame.
Appearance: Similar to slubs but thicker and more clustered (not slender); yarn does not break when slightly untwisted.
Causes: Airborne fiber clusters in the spinning mill or fiber accumulations on machine feeding surfaces winding onto the yarn.
Appearance: Spaced large slubs in a section of yarn across the fabric width, with bamboo-like thickness variations; most common in weft yarn of roving fabrics (also called bamboo weft).
Causes: Over-tight drafting roller setting, loose roller cover on the spinning frame, and occasional abnormal-length fibers in fed roving.
Appearance: Visible thickness variation of woven yarn across the fabric surface, mostly occurring in weft yarn.
Causes: Malfunction or poor performance of the drafting mechanism on the spinning frame, leading to intermittent thick and thin sections in spun yarn.
Appearance: Significant weft yarn count unevenness, with thick/thin weft yarns clustered together during weaving to form cloud-like patches on the fabric.
Causes: Regular weft yarn unevenness combined with clustered arrangement of thick/thin weft yarns during weaving.
Appearance: Sparse uncolored or lightly colored white fibers on dyed fabric surfaces.
Causes: 1) Dead cotton fibers in the cotton blend. 2) Accidental mixing of a small amount of polyester fiber during spinning; polyester does not absorb dye without disperse dyes and high-temperature dyeing.
Appearance: For chemical fiber, textured chemical fiber, or blended yarn fabrics (meeting count and density specifications), distinct shade variations between warp/weft yarns after dyeing.
Causes: 1) Use of same-denier chemical fiber with different production lots (differences in dye absorption, elasticity, and bulkiness cause shade variation after dyeing). 2) Blended yarn with specified count/density but inconsistent fiber blend ratio, leading to dye shade differences.
Appearance: Intermittent fabric width variations in E/C blended grey fabric after desizing, scouring, and bleaching.
Causes: Blended yarn requires high-pressure saturated steam setting in a sealed vessel after spinning to stabilize physical properties. Insufficient steaming temperature/time fails to set the yarn, causing transverse tight/loose sections on the fabric after scouring and bleaching.
Appearance: Uncolored fiber clusters on dyed fabric (more prominent in medium/dark shades).
Causes: Common in medium/low-grade dyed cotton fabrics; neps formed by dead cotton fibers are not removed during scouring/mercerizing and have poor dye absorption. Frequently occurs in dyed pure cotton open-end spun fabrics below 20Ne.
Woven Fabric Weaving Defects
Appearance: For knitted fabrics, continuous transverse loops woven with yarn of incorrect count (thicker/thinner than specified), appearing as single, side-by-side, or spaced yarns with uneven density/thickness.
Causes: Operator misuse of non-specified count/denier yarn during knitting (thinner yarn causes sparse fabric; thicker yarn causes dense/heavy fabric).
Appearance: Single or side-by-side warp yarns of incorrect count in woven fabrics; Fine End (thinner yarn) or Coarse End (thicker yarn).
Causes: Incorrect cone yarn count selected during warping, using non-specified warp yarn (often a full-bolt defect).
Appearance: Single or continuous weft yarns of incorrect count in woven fabrics; Fine Pick (thinner yarn) or Coarse Pick (thicker yarn).
Causes: Incorrect weft cone count used in shuttles or shuttleless looms; operators usually stop the machine to remove defective yarn, but automatic cone-changing looms make detection difficult.
Appearance: Weave pattern deviates from the design (e.g., left twill woven as right twill).
Causes: Mostly incorrect heald drafting; also faulty jacquard pattern cards or misarrangement of multi-specification warp yarns.
Appearance: Two adjacent warp yarns drawn as one during weaving, appearing abnormally thick (full-bolt defect; avoidable by removing one yarn if detected early in warping).
Causes: 1) Careless drawing of two yarns as one during warping. 2) Unseparated warp yarns sticking together after sizing. 3) Two yarns threaded into the same heald wire during drafting.
Appearance: Two (or more) weft yarns woven into the same shed, with varying lengths (most common across the full fabric width or 10cm from both selvedges).
Causes: 1) Restarting the loom without checking the shed after troubleshooting, or ineffective weft feeler (no auto-stop for weft breakage). 2) Insufficient safety yarn length, improper/dull side cutters, or unremoved weft tails after breakage (for partial-width double picks).
Appearance: Weft yarn density lower than specified, with a uniform-width sparse section where density gradually thins then recovers along the fabric length.
Causes: 1) Ineffective weft feeler (continuous warp feeding without weft). 2) Improper warp tension control during weaving. 3) Over-tight warp tension adjustment before restarting the loom.
Appearance: Weft yarn density higher than specified, with a uniform-width dense section where density gradually thickens then recovers along the fabric length.
Causes: 1) Improper warp tension control during weaving. 2) Over-loose warp tension adjustment when restarting the loom.
Appearance: Visible marks on the fabric after improper removal of defective weft yarn and subsequent weaving.
Causes: Severe friction to warp yarns during weft removal generates excessive hairiness, leaving a hairy strip in the repaired area after reweaving.
Appearance: One or more broken warp yarns, increasing the gap between adjacent yarns; appears as double ends in plain weave and interrupted twill lines in twill weave.
Causes: Warp breakage during weaving with ineffective auto-stop device, continuing to weave without splicing the warp.
Appearance: Short weft breakage with closely spaced ends (usually inconspicuous).
Causes: 1) Weft breakage during weaving with continuous insertion (only a small gap missing). 2) Severe slubs/flyers on weft yarn causing breakage during removal.
Appearance: Exclusive to twill weave; warp yarns float on the fabric surface at the same position of each repeat, resembling a centipede’s legs.
Causes: One missing weft pick reduces interlacing points, causing some warp yarns to float over two consecutive weft yarns.
Appearance: A short coiled/twisted section of a single warp yarn woven into the fabric (common in high-twist yarn fabrics).
Causes: Excessive slack of one warp yarn during warping leads to coiling.
Appearance: A short coiled/twisted section of a single weft yarn woven into the fabric (common in high-twist yarn fabrics).
Causes: 1) Pre-formed coiled/twisted weft sections in shuttles or cones. 2) Poor weft cone formation causing unsmooth unwinding. 3) Low weft tension or unclear shed opening.
Appearance: Large gaps between two warp yarns on grey fabric, with sawtooth marks on weft yarns caused by reed dents.
Causes: 1) Deformed or loose reed dents failing to position warp yarns correctly. 2) Excessive tension on single/spaced warp yarns during weaving.
Appearance: Needle pricks or scratches (2-5cm wide) on the selvedge; severe cases cause wavy weft yarns in the affected area.
Causes: Improper needle size of temple, seized or unsmooth rotating temple ring.
Appearance: Multiple consecutive broken warp yarns near the selvedge; residual yarn tails and uneven density in the spliced area after repair and reweaving.
Causes: Shuttle jamming in the raceway cuts multiple warp yarns (caused by poor shuttle design, obstructed picking/shedding); avoidable with shuttleless looms.
Appearance: Two adjacent warp yarns clump together, creating enlarged gaps between pairs of warp yarns and forming a checkerboard pattern with weft yarns.
Causes: 1) Excessively large shed opening angle during weaving. 2) Severe warp tension difference between upper and lower layers. 3) Uneven dent density of the reed.
Appearance: Protruding residual yarn tails on the fabric surface or selvedge.
Causes: Uncut yarn tails after warp/weft splicing, or ineffective loom side cutters failing to trim weft tails after cone change.
Appearance: Tight, large/small spherical knots protruding from the fabric surface.
Causes: Oversized knots formed during warp/weft splicing, bulging above the fabric.
Appearance: Warp/weft yarn floating on the fabric surface without following the specified weave.
Causes: Too small shed opening angle, uneven heald suspension, or excessive slack of individual warp yarns.
Appearance: Continuous floats at the same position of adjacent warp/weft yarns, forming a mesh with no interlacing points (severe form of float).
Causes: Same as float, with more severe conditions.
Appearance: Holes of varying sizes caused by broken warp/weft yarns (common in high-density woven fabrics).
Causes: Shuttle friction, roller snags, or shuttle jamming leading to warp/weft breakage.
Appearance: A single warp yarn protruding at interlacing points (also called rib stand in factories).
Causes: Low tension on a single warp yarn during weaving, or excessive slack after splicing.
Appearance: A single weft yarn protruding at interlacing points (usually inconspicuous).
Causes: Low tension on a single weft yarn during weaving.
Appearance: A single warp yarn lying flat with indented interlacing points (prominent in twill/satin weave; severe cases cause uneven fabric).
Causes: Excessive tension on a single warp yarn during weaving, or over-tight splicing after warp breakage.
Appearance: A single weft yarn lying flat with indented interlacing points (rare and less conspicuous than tight end).
Causes: Unsmooth weft unwinding from cones/shuttles, causing occasional excessive tension during insertion.
Appearance: Curved, slanted adjacent warp/weft yarns forming a gap.
Causes: Failure to comb adjacent warp/weft yarns with a steel comb after removing large slubs, flyers, warp snarls, or weft snarls.
Appearance: Residual marks after repairing severe weaving defects (e.g., broken ends, loose/tight reed).
Causes: Abnormal yarn arrangement and bending remain even after combing by repair workers with a steel comb.
Appearance: Uneven weft yarns with small sections bending in the same direction (common in fabrics with filament warp, staple weft, or fine warp/thick weft, e.g., rich satin, fleece, Oxford cloth).
Causes: 1) Improper weave design causing interlacing point slippage. 2) Low weft density combined with excessive warp tension during weaving. 3) Intermittent over-clamping during dyeing/finishing.
Appearance: Selvage splitting with three or more consecutive broken selvage yarns.
Causes: 1) Excessive tension on selvage yarns during weaving leading to breakage. 2) Improper/unmatched temple causing selvage yarn breakage.
Appearance: Straight selvage with loose/wrinkled fabric adjacent to the selvage; selvage is tighter than the fabric surface when spread flat (or the fabric sags).
Causes: Excessive tension on selvage warp yarns during weaving.
Appearance: Uneven, ruffled selvage (like a ruffle); fabric surface is flat but selvage is wrinkled/eared when spread flat.
Causes: Too low tension on selvage warp yarns during weaving.
Appearance: Uneven, sawtooth-shaped outer edges of both selvages.
Causes: 1) Insufficient selvage yarn count, or un-spliced broken selvage yarns. 2) Excessive picking force or weft unwinding tension.
Appearance: Periodic slight weft density variations (alternating loose/dense sections) across the fabric surface.
Causes: Unstable warp feeding tension or speed during weaving.
Appearance: Larger gaps between two columns of loops in knitted fabrics, with straight connecting threads between transverse loops.
Causes: Yarn failing to enter the needle during weft knitting, resulting in one missing column of loops.
Appearance: Unplanned pattern/design due to misarranged yarns in pre-dyed yarn fabrics or multi-specification yarn fabrics (common in stripe, check, and jacquard fabrics).
Causes: 1) Incorrect warp count arrangement (stripe/check fabrics) or wrong weft insertion count (check fabrics), causing abnormal patterns. 2) Misarrangement of multi-specification warp yarns during warping, or incorrect weft insertion.
Appearance: Dried size lumps/spots on the grey fabric surface.
Causes: Incompletely gelatinized sizing paste, worn pressure rollers, or uneven roller surfaces during sizing.
Appearance: Grey/black or pale red mildew spots on the grey fabric surface.
Causes: Excessively high humidity and long storage time.
Woven Fabric Dyeing & Finishing Defects
Appearance: Oil drop-shaped darker stains on E/R blended fabrics after dyeing; magnified view shows tiny bead-like fiber tips with more hairiness in stained areas.
Causes: Uneven singeing; unburned hairiness in stained areas forms fused tips with higher dye absorption, causing darker staining.
Appearance: Fine hairiness with inconsistent shade to the weave on dyed/finished fabric surfaces.
Causes: 1) Insufficient singeing failing to remove surface hairiness. 2) Excessively strong nozzle jet in jet dyeing machines.
Appearance: Straight longitudinal shade variations on dyed fabrics.
Causes: Warp yarn movement during dyeing causes uneven yarn density and gap variations, leading to visual shade differences.
Appearance: Drop-shaped dark dye spots on dyed polyester fabrics.
Causes: 1) Poor carrier dispersion in atmospheric polyester dyeing, forming spots after dye absorption. 2) Volatilized carrier condenses on the dyeing machine top and drips onto the fabric.
Appearance: Rain-like warp-wise streaks on piece-dyed woven fabrics (visible on grey fabric in severe cases); visibility varies with light, viewing angle, and distance.
Causes: 1) Differences in yarn count, evenness, twist, and cross-section of weaving yarns. 2) Improper dye selection (common in green dyeing). 3) Improper desizing of textured polyester fabrics (residual size causes lighter, unstained warp streaks).
Appearance: Continuous weft-wise/transverse shade bands (darker/lighter) on dyed woven/knitted fabrics.
Causes: 1) Loose/tight reed defects on grey woven fabric. 2) Uneven yarn feeding tension or loop density during knitting. 3) Use of same-specification different-lot chemical filament yarns during weaving. 4) Uneven heating during chemical filament processing for knitting.
Appearance: 1) Tiny same-shade spots on medium/light dyed fabrics. 2) Tiny foreign-dye spots on bleached/light dyed fabrics.
Causes: 1) Poor dye dissolution with undissolved particles. 2) Airborne dye settling on unprocessed fabric during transportation. 3) Unclean equipment when processing light fabrics after dark fabrics.
Appearance: Irregular longitudinal shade wrinkles on fabric dyed in rope form (caused by rope shrinkage).
Causes: Unset or under-set fabric in jet/rope dyeing machines, broken roller in the dyeing machine, sudden temperature change, too small liquor ratio, or fabric knotting in the cylinder.
Appearance: Lighter folded areas on open-width pad-dyed woven fabrics (caused by uneven liquor pick-up from thickness differences at folded warp-wise sections); common at fabric head/tail.
Causes: 1) Pre-formed creases not eliminated during setting. 2) Ineffective expander in the pad dyeing machine feeding device. 3) Poor fabric joining with wrinkles/irregularities between bolts.
Appearance: Wood grain-like luster spots on dyed fabric surfaces.
Causes: 1) Excessive fabric shrinkage during beam dyeing causes layer movement. 2) Over-tight winding during beam dyeing disrupts liquor circulation.
Appearance: Selvage shade different from the fabric surface after dyeing.
Causes: 1) Over-loose/over-tight grey fabric selvage. 2) Selvage clamped by high-temperature plates during pre-dye setting. 3) Selvage curling during dyeing. 4) Uneven winding during open-width beam dyeing causes selvage oxidation. 5) Insufficient reduction during open-width beam dyeing with sulfur/vat dyes. 6) Uneven liquor pick-up between selvage and fabric surface in pad dyeing. 7) Incomplete washing after dyeing with residual chemicals on the selvage.
Appearance: Selvage shade variation on finished dyed/printed fabrics.
Causes: 1) Excessively high pin/plate temperature during resin finishing causes dye sublimation. 2) Over-high temperature in tumble dryers with over-tight fabric winding around the cylinder.
Appearance: Abnormal dyeing at the folded edges of tubular knitted fabrics.
Causes: 1) Deteriorated lubricant applied during weaving. 2) Improper/long storage causes selvage discoloration/contamination from air and sunlight. 3) Over-high temperature of the setting frame during tubular setting.
Appearance: Large, light-colored crease marks on dyed fabrics (irregular size/direction; common in E/C blended woven fabrics).
Causes: Dry stainless steel conveyor belt at high temperature in continuous scouring/bleaching machines adheres to folded fabric, reducing dye absorption in contact areas.
Appearance: Large, irregular foreign-color contamination on fabric surfaces.
Causes: 1) Contact between wet fabric and dyed fabric of different shades (more obvious with contrasting colors). 2) Unclean equipment during processing/transportation.
Appearance: Large white/light streaks on fabric surfaces after drying, caused by adhered foam residue.
Causes: 1) Excessive foam in dye liquor (improper dispersant/auxiliary selection). 2) Excessive foam in reducing liquor (common in vat dye reduction). 3) Floating scum from non-diazotizable impurities in phenol developing solution.
Appearance: Dark streaky/short band contamination on dyed fabrics, caused by dye-dye/dye-auxiliary agglomeration and poor dissolution.
Causes: 1) Poor dye dissolution/dispersion, mixed chemicals in dye, or over-hard dyeing water. 2) Incompatible dye-auxiliary combinations, or improper auxiliary addition timing/sequence.
Appearance: Small patches of contamination on fabric surfaces with regular spacing, caused by unclean cylindrical equipment (oil, chemicals, dye, dirt) during dyeing/finishing.
Causes: 1) Oily guide rollers. 2) Tarry lake or staple fiber deposits on pressure rollers. 3) Oil/dirt on drying cylinders.
Appearance: Spotted/patchy discoloration, contamination, or degradation on fabric surfaces.
Causes: Infiltration of unapproved chemicals into the fabric.
Appearance: 2-10cm wide weft-wise/transverse shade bands (darker/lighter) with watermark-like edges, caused by machine stop during dyeing.
Causes: Sudden machine stop (power failure, winding, malfunction) during pad dyeing/reduction, with fabric clamped between rollers leading to uneven liquor absorption.
Appearance: Darker same-shade spots on packaged finished fabric after opening.
Causes: Sealed packaging of dyed/finished fabric causes condensed water vapor to migrate low wet-fastness dyes/auxiliaries, forming spots.
Appearance: Unclear printed pattern lines with a fuzzy look (common in roller printing).
Causes: Poor engraving of printing rollers or insufficient doctor blade pressure.
Appearance: Disaligned or gap-filled multi-color printed patterns (failure to follow design alignment).
Causes: Inaccurate plate alignment for multi-color printing.
Appearance: Partial/complete loss of designed printed pattern.
Causes: 1) Empty paste trough in roller printing machines (no timely refilling or automatic paste feeder malfunction). 2) Paste pump failure in rotary screen printing machines.
Appearance: Intermittent fine printed lines.
Causes: 1) Too shallow engraving (roller printing) or too large mesh (rotary screen printing) for fine lines, hindering paste penetration. 2) Over-high viscosity of printing paste.
Appearance: Shuttle/longitudinal unprinted areas on printed fabrics (caused by folded fabric during printing).
Causes: Fabric wrinkling/overlapping during printing covers areas and prevents paste application.
Appearance: Tiny unprinted dots or blurred spots on printed fabrics (common in screen/rotary screen printing).
Causes: Paste lumps adhering to the printing plate block paste penetration.
Appearance: Unsharp printed patterns with color bleeding outside the design.
Causes: 1) Too low viscosity of printing paste. 2) Overlapping of multi-color printing pastes.
Appearance: Uniform light contamination of white-ground printed fabrics with a small amount of printing paste (common in roller printing).
Causes: 1) Poor finish of printing rollers leading to paste adhesion. 2) Poor doctor blade contact with rollers or dull, unsharpened blades (common in white-ground black/dark large patterns).
Appearance: Neat-ended single-color streaks on printed fabrics (wider streaks show colorless centers with fading edges).
Causes: Paste lumps/clusters sliding across the printing roller surface under doctor blade pressure during roller printing.
Appearance: Unintended fine lines on roller-printed fabrics (not on the engraving), running warp/weft-wise.
Causes: Poor roller engraving/finishing with damaged pattern edges from doctor blade pressure, or hard debris in paste scratching the roller from pattern grooves.
Appearance: Smudged trails next to printed dots (roller printing) along the fabric length, causing irregular pattern edges.
Causes: Excessive paste pick-up, uneven fabric feeding/take-up tension, or hairiness accumulation on the doctor blade.
Appearance: Wavy shade variations along the fabric length in printed patterns.
Causes: Improper doctor blade installation and pressure in roller printing machines.
Appearance: Misaligned continuous printed patterns at plate joints (common in screen printing).
Causes: 1) Poor screen plate making. 2) Inaccurate plate gap control before printing.
Appearance: A blurry pattern line across the fabric width (uneven blurriness) in roller printing.
Causes: Thick, overlapped splices on endless backing cloth absorb more moisture; wet backing cloth wets the printed fabric and causes paste bleeding/diffusion.
Appearance: 5-15cm wide full-width mixed-color stain across printed fabrics (no pattern) at machine stop.
Causes: Printing rollers/screens not lifted immediately after machine stop, pressing excess paste into the fabric.
Appearance: Light circular/large patches on dyed/printed fabrics with darker edges (caused by condensed water).
Causes: Condensed water droplets from factory steam fall on untreated dyed/printed fabric during storage, forming irreversible discoloration (crystalline water bonds with dye); may be restored with high-temperature ironing (prominent in vat-dyed cellulosic fabrics).
Appearance: Irregular light patches on fabric after development (for pre-padded/dyed/printed fabrics).
Causes: 1) Improper ratio of phenol dye padding and color solutions. 2) Over-high drying temperature after padding. 3) Incompletely dissolved reducing agent for continuous dyeing. 4) Incomplete air removal from the steamer (fabric contact with air during steaming). 5) Uneven steamer temperature. 6) Incomplete dye oxidation. 7) Direct sunlight exposure of fabric before development.
Appearance: Dried resin lumps on resin-finished fabrics (shiny, smooth, and stiff to the touch).
Causes: Incompletely dissolved resin in the finishing bath adheres to the fabric, then is pressed into firm lumps by rollers.
Appearance: Resin floating on the surface of resin-finished fabrics, with visible scratch marks from light fingernail contact.
Causes: Over-high resin pick-up and excessively high initial drying temperature during resin finishing.
Appearance: Fiber pills on resin-finished fabrics (common in wool, polyester staple, and polyester-blended fabrics).
Causes: 1) Excessive surface hairiness on fabric before resin finishing. 2) No anti-pilling or smoothness agent added to the resin bath.
Appearance: One column of loops stretched straight in weft-knitted fabrics.
Causes: Incorrect fabric feeding direction during setting/resin finishing stretches one column of loops straight.
Appearance: Excessively smooth fabric with unwanted shine (common in chemical fiber knitted fabrics).
Causes: Excessive tension applied to the fabric during resin finishing.
Appearance: Uneven, bumpy fabric surface when a 1-yard full-width section is spread flat (common in weft-knitted fabrics).
Causes: Poor setting/resin finishing leading to uneven longitudinal/transverse shrinkage.
Appearance: Stretched elastic knitted fabrics fail to recover shape and show wrinkles (longitudinal/transverse).
Causes: 1) Low crimp fastness of elastic yarn used in weaving. 2) Over-high setting/resin finishing temperature or excessive heating time, reducing the elasticity of textured yarns.
Appearance: Smooth, slightly stiff fabric with low elasticity (paper-like feel).
Causes: Chemical filament yarns with ultra-low boiling water shrinkage (2-3%) fail to shrink sufficiently during processing, resulting in a paper-like texture.
General Contamination & Mechanical Defects
Appearance: A single section of warp yarn contaminated with oil/grease.
Causes: Warp yarn impregnated with machine lubricant during winding, cone winding, or weft winding before weaving.
Appearance: A single section of weft yarn contaminated with oil/grease.
Causes: Weft yarn impregnated with machine lubricant during winding, cone winding, or weft winding before weaving.
Appearance: A single section of yarn contaminated with oil/grease in knitted fabrics.
Causes: Oil/grease contamination during cone winding or transportation before weaving.
Appearance: Irregular oil/grease stains (drop/patch-shaped, varying sizes) on grey/finished fabrics.
Causes: 1) Lubricant splashes during weaving/dyeing/finishing. 2) Oil/grease contamination during transportation.
Appearance: Air-dried water marks on grey/finished fabric surfaces.
Causes: 1) Water immersion of grey/finished fabric. 2) Residual marks after washing oily warp/weft or oil stains on grey/finished fabric.
Appearance: Variations in fabric luster, shade, or weave caused by friction during processing.
Causes: 1) Accidental friction during fabric conveying/storage. 2) Slippage between elliptical rollers and fabric in jet dyeing machines. 3) Friction against rough machine surfaces during processing.
Appearance: Holes caused by broken warp/weft yarns on grey/finished fabric surfaces.
Causes: Impact by sharp objects during transportation/storage, or use of hooks for manual handling.
Appearance: Wide, uneven grooved fold marks on the fabric (disappear under tension; common along the fabric length and at head/tail).
Causes: 1) Uneven grey fabric folding and over-high pressure during baling. 2) Wrinkles at fabric joints in pre-treatment. 3) Ineffective fabric expander or over-high tension in pre-treatment feeding. 4) Uneven or bent guide rollers in pre-treatment wash troughs. 5) Improper angle or worn curved expanders before pressure rollers in pre-treatment (uneven fabric spreading). 6) Wrinkled fabric winding around tumble dryers. 7) Failure to stretch pre-formed creases during fabric widening/setting.
Appearance: Uneven length/density of naps/loops on raised fabrics (e.g., fleece, corduroy, velvet, towels).
Causes: 1) Fabric wrinkling or uneven tension during raising. 2) Uneven shearing for corduroy/velvet. 3) Uneven loop size from pile warp during towel weaving.
Appearance: Easily pulled/loose naps on sheared fabrics.
Causes: Improper weave design with insufficient gripping force on sheared nap yarns.
Appearance: Large areas of displaced yarns with wavy, uneven density (common in fabrics with fine filament warp and staple weft).
Causes: 1) Too small liquor ratio, over-long fabric, fast elliptical roller speed, or abnormal tension from fabric knotting in jet dyeing machines. 2) Too small liquor ratio, over-high fabric load, or excessive nozzle jet in jet dyeing machines. 3) Over-large expansion angle of guide/expander rollers in open-width continuous processing.
Post time: Feb-02-2026