Common fabric defects and its causes

Common fabric defects and its causes

Common Defects of Fabrics during manufacturing process includes back fabric seam impression, birds eye, bowing, broken colour pattern, colour out, colour smears, crease mark, drop stitching, dye streak in printing, hole, jerk in, knots, mixed yarn, mottled, needle line, open reed, pin holes, press off etc.

Often inspectors are given the responsibility of inspecting finished garments without adequate training in fabric defects and their causes. The ultimate solution, of course, is to provide actual examples or photographs of both major and minor defects. This section provides a list of defects and explanations and simplifies the language and the judgments used in making visual fabric evaluations. The Quality Control Manager can provide this list to inspectors as a practical tool for achieving uniform inspection decisions.

Major and Minor Defects

The following definitions are central to fabric inspection:

Major Defect

A defect that, if conspicuous on the finished product, would cause the item to be a second. (A “second” is a garment with a conspicuous defect that affects the salability or serviceability of the item.

Minor Defects

A defect that would not cause the product to be termed a second either because of severity or location. When inspecting piece goods prior to cutting, it is necessary to rate questionable defects as a major, since the inspector will not know where the defect may occur on the item.

Fabric Defect Depictions

Fabric defect due to the hole

Fabric defect due to stain

Float defect in the fabric

Fabric weft yarn defect

Fabric warp yarn defect

Double pick defect in the fabric

Double end defect in the fabric

Insufficient weft density defect in the fabric

Excessive weft density defect in the fabric

Fabric broken pick defect

Broken end defect in the fabric

Glossary of Defects

DefectCauseSeveritySkewed or BiasCondition where filling yarns are not square with wrap yarns on woven fabrics or where courses are not square with wale lines on knits.Major or MinorBack Fabric Seam ImpressionBacking fabric is often used to cushion fabric being printed. If there is a joining seam in the backing fabric, an impression will result on printed fabric.MajorBarreOccurs in circular knit. Caused by mixing yarn on feed into the machine. Fabric will appear to have horizontal streaks.Usually MajorBirds EyeBirds eye often caused by unintentional tucking from malfunctioning needle. Usually two small distorted stitches caused side by side.Major or Minor depending on severityBurl MarkWhen a slub or extra piece of yarn is woven into the fabric, it is often removed by a “burling tool.”This will usually leave an open place in the fabric.MajorBowingUsually caused by finishing. Woven filling yarns lie in an arc across fabric width. It is critical on stripes or patterns and not as critical on solid color fabrics.Major or MinorBroken Color PatternUsually caused by colored yarn out of place on the frame.MajorColor OutColor out is the result of color running low in a reservoir on the printing machine.MajorColor SmearsColor Smears are the result of color being smeared during printing.Major or MinorCrease MarkDiffers from crease streak in that streak will probably appear for an entire roll. Crease mark appears when creases are caused by fabric folds in the finishing process. Often discoloration is a problem.MajorCrease StreakOccurs in tubular knits. Results from creased fabric passing through squeeze rollers in dyeing process.Depending on the product.Usually MajorDrop StitchingDrop stitching results from malfunctioning needle or jack appearing as holes or missing stitches.MajorDropped PickCaused by the filling insertion mechanism on a shuttleless loom not holding the filling yarn,causing the filling yarn to be woven without tension. The filling yarn appears as “kinky”.There will also be areas of “end out”.MajorDrawbacksCaused by excessive loom tension gradually applied by some abnormal restriction. When the restriction is removed the excess slack is woven into the fabric. Usually the ends are brokenMajorDye Streak in PrintingResults from a damaged doctor blade or a blade not cleaned properly. Usually a long streak until the operator notices the problem.MajorEnd outCaused by yarn breaking and loom continuing to run with the missing end.MajorJerk-in Caused by an extra piece of filling yarn being jerked part way into the fabric by the shuttle. The defect will appear at the selvage.Usually MajorHoleHoles in fabrics are usually caused by the broken needle.MajorJerk InJerk Ins is caused by an extra piece of filling yarn being jerked part way into the fabric by the shuttle. The defect will appear at the selvage.Major or MinorKnotsKnots are caused by tying spools of yarn together.Usually MinorMissing YarnOccurs in circular knit. Caused by one end of yarn missing from feed and machine continuing to run.MajorMixed FillingCaused by bobbin of lightweight yarn or different fiber blend used in filling. Will appear as a distinct shade change.MajorMixed YarnMixed yarn is a different fiber blend used on the warp frame, resulting in a streak in the fabric.Usually MajorMottledMottles occurs when colors applied unevenly during printing.Major or MinorNeedle LineNeedle Line is caused by bent needle forming distorted stitches in a vertical line.Major or MinorOpen ReedOpen reed are the results from a bent reed wire causing warp ends to be held apart, exposing the filling yarn.MajorPin HolesPin holes along selvage caused by pins holding fabric while it processes through tender frame.

Major> if pin holes extend into the body of fabric far enough to be visible in the finished productMajorPress OffPress Off occurs when all or some of the needles on circular knitting fail to function. Fabric either falls off the machine or design is completely disrupted or destroyed.MajorPrinting Machine Stop MarkDye or ink smudged along the width of fabric as a result of the printing machine stopping.Print Out of RepairCaused by print rollers not being synchronized properly. This results in various colors of the design not being printed in the proper position.Puckered SelvageUsually caused by selvage being stretched in finishing or by uneven wetting out in sanforization process.MajorRunnerRunner is a caused by the broken needle. The runner will appear as a vertical line. Most machines have a stopping device to stop the machine when a needle breaks.Major or MinorSanforize PuckerUsually caused by defective spray heads resulting in uneven wetting out of Sanforize. Fabric will appear wavy or pucker when spread on cutting table. It is difficult to detect while inspecting on inspection machine with fabric under roller tension.Major or MinorScrimpScrip is the result of fabric being folded or creased when passing through tender frames.MajorSkewingSkewing refers to a condition where filling yarns are not square with warp yarns on woven fabrics or where courses are not square with wale lines on knits. It happens when the fabric shrinks more perpendicular to the twill line than along the twill line.SlubSlub refers to thick or heavy places in the yarn or flying waste yarn getting into yarn feeds during the spinning process. Slub and other inconsistencies are common in fabrics produced on vintage shuttle looms.Major or MinorSmashSmall caused by a number of ruptured warp ends that has been repairedMajorSoiled FillingSoiled filling is dirty oily looking spots on the warp or filling yarns, or on packaged-dye yarn.Can be Major or MinorStop MarkStop mark occurs when the loom is stopped, the yarn elongates under tension. When the loom starts again, the slack is woven into the fabric.Can be major or MinorStraying EndStraying End is caused when an end of yarn breaks and the loose end strays and is knit irregularly into another area.Thin PlaceThin Place is often caused by the filling yarn breaking and the loom continuing to run until the operator notices the problem.MajorWater SpotsWater spots are usually caused by wet fabric being allowed to remain too long before drying, Color migrates leaving blotchy spots.MajorPillingPilling refers to the forming of little-matted balls on the surface of knitted fabrics. Pilling occurs when soft yarn rubs against itself, resulting in tangled fibers and produces an uneven and worn look.