Common terminology used in Denim fabric construction and processing

ANTI-TWIST is a step in the finishing process, before sanforization, that corrects denim’s natural tendency to twist in the direction of the diagonal twill weaves. It is also known as skewing.

BLACK-BLACK DENIM is a term used for denim where the warp yarn is blackinstead of blue and which is also dyed black after weaving. This makes the jeans truly black rather than gray.

BROKEN TWILL is a denim weave invented by John Neil Walker in which thedirection produced by the weft thread is reversed after not more than two passages of the warp to create a sporadic design – a zigzag weave pattern.

BULL DENIM is a heavyweight denim weave (14oz. plus) with a typical 3x1twill construction. An ecru fabric, bull denim is later printed or garment dyed.

CROSSHATCH is a unique type of denim that shows a square grid-like pattern in the weave. It is created by mixing uneven yarns in both the weftand warp directions.

DENIM is an indigo-dyed cotton twill fabric in which the weft passes under two or more warp fibers. The term derives from ‘Serge De Nimes’, the French city where it was produced; but denim and Serge De Nimes are in fact different fabrics.

DIPS are used to describe fabric or yarn when they are immersed in dye.Indigo yarns are usually dipped in an indigo bath six times.

DUAL RING-SPUN is also called “ring X ring”. Signifies a denim weave inwhich both the warp and the weft threads are made of ring-spun yarn. Itcreates a much softer and textured hand than both open-end and regular (single) ring-spun denim. Due to higher production costs it is usually only used by higher end, premium denim labels.

HANK DYEING is a very special dyeing process that very few people use. The yarns are loosely arranged in skeins or hanks. These are then hung over a rung and immersed in a dye bath being dipped in and out and leftto oxidize in the air between each dip giving the yarns a natural irregularity of patina and caste. In this method, the color penetration is the best and the yarns retain a softer, loftier feel.

INDIGO is common dye used for denim, initially taken from the indigo Fera Tinctoria plant. The majority of indigo used today is synthetically made. Natural indigo has a slightly red cast.

LEFT-HAND TWILL is also known as an ‘S Twill’, this is a weave in whichthe grain lines run from the top left-hand corner of the fabric towardsthe bottom right. Usually in piece dyed fabrics, left hand twill fabrics are woven from single plied yarns in the warp. Left-hand twills will often have a softer hand feel to them after washing than right hand twills. This twill is also much more difficult to produce, since it requires more attention in the sanforization and finishing processes.

LOOP DYED is one of the three major industrial methods of dyeing the indigo yarns. In the loop dyeing process, the yarn is dyed in a single bath instead of several. The desired depth of color is attained by passing the yarn through the vat several times.

Subsequently as part of the same process, the yarn is sized.

MERCERIZATION is an industrial process used on yarn or fabrics to increase its luster and dye affinity. For fabrics used in the denim industry, mercerization can be used for keeping dye on the surface of the yarns or fabrics and to prevent dyes from fully penetrating the fibers.


NATURAL DENIM is a type of ring-ring denim which is naturally uneven in warp and weft.

OPEN END DENIM is so called when Open End or OE spinning was introducedin the 1970s, reducing costs by omitting several elements of the traditional spinning process. The cotton fibers are ‘mock twisted’ by blowing them together. Open End denim is bulkier, coarser and darker, because it absorbs more dye, and wears less
well than Ring Spun denim.

ORGANIC BLUE is a name given to an indigo dye that has a slightly reddish tint.

OVER TWISTED DENIM is made from yarn that is over twisted, giving the fabric a

particular crinkled surface.

POLYCORE DENIM is often found in replica jeans, offers the best mix of strength of

polyester core and vintage aesthetic of cotton top thread layer.

OXIDATION occurs when oxygen and another substance chemically react. This occurs

when indigo yarn comes out of the bath between dips.

PIGMENT DYES do not have an affinity for fiber and must therefore is held to the

fabric with resins. They are available in almost any color and are used extensively in

the denim industry by fabric dyers who want to create fabrics that fade more easily.

PLY- All yarns are single ply unless twisted with another yarn. Plied yarns are used to

make yarns stronger. In the denim industry, it has become important to ply yarns in

piece dyed fabrics that are intended to endure a long stone wash cycle. The method

of twisting and length of each yarn is a major determinant in the ultimate look and

feel of the finished fabric.

PRINTED DENIM is that has been printed with a pattern-a batik, stripe, floral or

special graphics, for example- often in contrasting colors and aimed at response to

the fashion trend.

QUARTER DIP is a shortened dyeing process normally used for chambray and

lightweight denims, in which the number of indigo dips is reduced to two or four,

instead of the usual six to eight, resulting in a lighter shade of blue.

RAPID SKYING is a patented oxidation process developed by Tessitura di Robecchetto

Candiani in 1992 that speeds up the skying step of the indigo dyeing process and

therefore shortens the indigo dyeing technique.

RED INDIGO is a special synthetic dyestuff that’s a lighter shade of blue originally

used as an alternative to real indigo when there was a shortage of the natural dye.

Had a peak period in the ‘60s, and resurfaced as a selling attraction in the ‘90s. It is

also known as Hydron Blue.

REVERSE DENIM is a novelty use of denim when it is turned inside out to give jeans a

really different look.

RING-SPUN DENIM- Ring spun yarns were traditionally used in denim up until the late

1970s, but were later exchanged by using cheaper Open End yarns. This is a spinning

process in which the individual fibers are fed onto the end of the yarn while it is in

the’ twisting’ stage. The process consists of a ring, a ring traveler and a bobbin that

rotates at high speed. The ring-spun yarn produced by this method creates unique

surface characteristics in the fabric, including unevenness, which gives jeans an

irregular authentic vintage look. Ring-spun yarns add strength, softness and character

to denim fabric.

RING-RING DENIM or double ring-spun denim uses ring-spun yarn for both warp and

weft. This is the traditional way to produce denim. It’s possible to combine a ringspun

warp fabric with an Open End weft, to get much of the strength and look of the

traditional ring/ring denim at lower cost.

RING DENIM is a traditional type of denim fabric, revived in the late ‘80s and early

‘90s, using ring-spun yarn for the warp. It is characterized by a softer hand and an

uneven surface appearance.

RING DYEING is a process which describes a characteristic unique to indigo dye in

which only the outer ring of the fibers in the yarn is dyed while the inner core

remains white.

ROPE DYEING is considered the best possible method to dye indigo yarns. The

threads of denim yarn are twisted into a rope, which is then fed through sequence of

being dipped into a bath of indigo dye, followed by exposure to air, multiple times.

The frequency determines the ultimate shade of blue.

SANFORIZATION is a pre-shrinking fabric process that limits residual fabric shrinkage to less than 1%. The process includes

the stretching and manipulation of the denim cloth before it is washed. Raw, un-sanforized jeans will shrink 7-10% after the

first wash, and continue to shrink slightly up to the third wash. Developed in the late 1920s by the Sanforize Co. and

patented in 1928.

SELVAGE or selvedge came from ‘SELF-EDGE’ is also referred to as ‘Redline’ or ‘AkaMimi’. Selvage is the narrow tightly

woven band on either edge of the denim fabric, parallel to the warp. A selvage end prevents the edge of the denim from

unraveling. In some fabrics selvages are closed, whereas on larger modern weaving machines, the weft yarn is cut on every

pick, creating what is called a ‘fringe’ selvage.

SHRINKAGE- Traditionally before denim is woven, the threads it’s made of are treated with wax or resin to stiffen them and

make them easier to weave (although with most repro denim starch is used instead.) When dry/raw/unwashed denim is

washed for the first time the fibers constrict and the denim shrinks. Raw denim can be Sanforized (treated with a

sanforizing process that lessens shrinkage) but all raw denim will shrink to some degree upon immersion in water, up until

its third wash.

SLASHER DYEING is one of three main methods of dyeing indigo yarn.

SPANDEX is generic name for man-made fibers derived from a resin called segmented polyurethane. It has good stretch

and recovery properties. Special attention is required during denim washing in order to maintain their properties.

SULPHUR BOTTOM is a term used when manufacturers apply a sulphur dye before the customary indigo dye; this is known

as Sulphur Bottom dyeing. This can be used to create a grey or yellow ‘vintage’ cast.

VENETO is a northern Italian region considered the cradle for some of the most successful names of the International jeans

industry. Denim brands such as Diesel, Replay, Gas and Seal Kay were all born and raised here as were famous laundries

such as Martelli.

VINTAGE is from the past; old or second hand. Vintage jeans can either be previously worn or never worn and sorted in

their original state.

WEIGHT of denim is traditionally graded by its weight per yard of fabric called as oz.

YARN DYE refers to fabric in which the individual yarns are dyed prior to weaving- denim is a yarn dyed fabric as the warp

yarn is dyed with indigo.