Common fabric defects and its causes

What is Defect?

Defect is the thing occurs in the fabric which makes the fabric or the finished product unacceptable to the desired quality level. If we categorized the defect than there will be two categories. One is major defect and another one is minor defect.                                              

Know about 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 service ability 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 major, since the inspector will not know where the defect may occur on the item.

Various Defects and their causes

Skewed or Bias:

A skewed or Bias Condition where filling yarns are not square with wrap yarns on woven fabrics or where courses are not square with wale lines on knits.

Back Fabric Seam Impression

Back Fabric Seam Impression Backing 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.

Barre

Barre Occurs in circular knit which caused by mixing yarn on feed into machine. Fabric will appear to have horizontal streaks.

Broken picks

The picks broke most probably because of abrasion on the back side of the fabric.

Birds Eye

Birds eye often caused by unintentional tucking from malfunctioning needle. Usually two small distorted stitches caused side by side.

Burl Mark

Burl Mark When 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.

Bowing

Bowing usually 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

Broken Color Pattern

Broken Color Pattern Usually caused by colored yarn out of place on frame.

Color Out

Color out is the result of color running low in reservoir on printing machine.

Color Smears

Color Smears are the result of color being smeared during printing.

Crease Mark

Crease Mark Differs 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.

Crease Streak

Crease Streak Occurs in tubular knits. Results from creased fabric passing through squeeze rollers in dyeing process.

Drop Stitching

Drop stitching is resulted from malfunctioning needle or jack appearing as holes or missing stitches.

Double pick

It causes when two picks are mistakenly inserted instead of one. Characteristic feature of certain rapier looms. The yarn is not transferred to the receiving rapier leading to a double pick in half the width of the fabric and no pick in the remaining half.

Dropped Pick

Dropped Pick Caused by the filling insertion mechanism on a shuttle less 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".

Drawbacks

Drawbacks Caused 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 broken.

Dye Streak

Dye Streak in Printing Results from a damaged doctor blade or a blade not cleaned properly. Usually a long streak until the operator notices the problem.

End out

End out Caused by yarn breaking and loom continuing to run with missing end. Major Jerk-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.

Fly

Foreign fly between loops of constructed fabric Unclean environment or improper maintenance of machine can cause fly to end up in the knitting zone where it becomes part of the fabric.

Hole

Holes on fabrics are usually caused by broken needle.

Knots

Knots are caused by tying spools of yarn together.

Missing Yarn

Missing Yarn Occurs in circular knit which caused by one end of yarn missing from feed and machine continuing to run.

Mixed Yarn

Mixed yarn is a different fiber blend used on the warp frame, resulting in a streak in the fabric.

Needle Line

Needle Line is caused by bent needle forming distorted stitches in a vertical line.

Open Reed

Open reed are the results from a bent reed wire causing warp ends to be held apart, exposing the filling yarn.

Pin Holes

Pin holes along selvage caused by pins holding fabric while it processes through tender frame.

Printing Machine Stop Mark

Printing Machine Stop Mark Dye or ink smudged along width of fabric as a result of the printing machine stopping.

Skewing

Skewing refers to 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.

Slub

Slub refers to thick or heavy places in the yarn or flying waste yarn getting into yarn feeds during spinning process. Slub and other inconsistencies are common in fabrics produced on vintage shuttle looms.

Stop Mark

Stop mark occurs when the loom is stopped, the yarn elongates under tension. When the loom starts again, the slack is woven into the fabric.

Thin Place

Thin Place is often caused by the filling yarn breaking and the loom continuing to run until the operator notices the problem.

Water Spots

Water spots are usually caused by wet fabric being allowed to remain too long before drying, Color migrates leaving blotchy spots.

Pilling

Pilling 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.

Weft Float

Weft yarns which haven’t been overlapped for a particular region of the fabric and just lie above the fabric in the form lose yarns.it causes because Series of warp yarns getting stuck in their bottom position resulting in the yarns not being lifted during weft insertion.

Laddering

Continued knitting with a broken needle.