“Know your denim”
ABRASION: The process of making garments look worn and aged by scraping the surface of the fabric causing abrasion. Pumice stones are most frequently used by industrial laundries. You can replicate this process with a rotary tool or sand paper.
ACID WASH: (aka Marble wash/Moon wash/Snow wash)This finish gives indigo jeans sharp contrasts. The process is achieved by soaking pumice stones in chlorine. The process was created in Italy and patented in 1986.
ATARI: (aka whiskering) A Japanese term describing the selective fading of the ridges of creases. The most common areas for “Atari” are along the side seams, on the front and back of the knees, the upper thigh, along the hem, on the belt loops and pocket seams.
BARTAK: A sewing procedure that reinforces stress points on jeans. Usually found near zippers and pocket openings.
BEAM: In the denim manufacturing process, a beam refers to a cylinder on which the warp yarns are wound for further processing.
Big E: Refers to Levi’s jeans produced in 1971. Up to that time, the name “LEVI’S” was written in all capital letters on the red “tab device” sewn in the back pocket. After this time, the “e” was written in lower case “LeVI’S” Levi’s jeans with a big E are considered vintage and more valuable than the latter.
BLEACH: A chemical used to fade denim. Liquid bleach is usually an aqueous solution of sodium hypochlorite, and dry powdered bleaches contain chloride of lime (calcium hypochlorite).
BROKEN TWILL: A Denim weave first used by Wrangler in 1964, as style 13MWZ. The diagonal weave of the twill is intentionally reversed at every two warp ends to form a random design. This type of weave reduces the natural torque characteristic of regular twill weaves, and has the effect of eliminating leg twist.
BULL DENIM: A 3×1 twill weave piece dyed fabric made of coarse yarns; weights can very from 9oz per square yard up to the standard 14oz per square yard. Basically, denim without indigo.
CAST: A term that describes shading. Depending on the method and type of dye used, indigo can have a black, brown, grey, green, red, or yellow cast to it.
CELLULOSE ENZYME WASH: Enzymes are like yeast and are used to eat away the cellulose in cotton. Denim is colored on the outside; when denim is washed in a cellulose enzyme bath the indigo is removed along with the fiber. When the desired color has been achieved- either by changing the alkalinity of the bath or heating the water (stops the enzymes from reacting). A rinsing and softening cycle follows. This process is environmentally friendly as strip-mined pumice stones are not used.
CROCKING: A term used to describe how dye rubs off fabric to skin or other fabrics. Because indigo is on the surface of the jean, color transfer is an issue. A resin or a fixative provides resistance to crocking. SEE Denim Laundering page for more solutions.
CROSSHATCH: A unique type of denim that shows a square grid-like pattern in the weave. It is created by mixing uneven yarns in both warp and weft directions.
DENIM: A cotton fabric made with indigo dyed warp yarns woven with natural weft yarns in a regular twill weave.
DESIZING: An amylase enzyme rinse used to soften denim. A type of size such as cornstarch is added to the warp yarns prior to weaving in a process called SLASHING, which adds stiffness to the yarns. During the desizing step, the amylase enzyme attacks the starch and removes it from the fabric. This is how denim is able to drape.
DIPS: Used to describe yarn when they are immersed in dye. Indigo yarns are usually dipped in an indigo bath six times.
DUAL RING-SPUN: (aka ring X ring) Signifies a denim weave in which both the warp and the weft threads are made of ring-spun yarn. This creates a soft and textured hand both open-end and regular ring-spun denim. Due to the additional labor required to produce dual ring-spun denim, it is usually only used by higher end premium labels.
END: An individual warp yearn. Denim weaves are expressed as the number of ends per inch X the number of pricks per inch. A typical weave is 66X46
Enzymes: are proteins present in all living things, increase the speed of chemical processes that would generally run slow if at all. They are non-toxic and readily broken down. Enzymes are used during the textile finishing process.
Enzyme Wash: is a more efficient and environmentally sound way to stone wash jeans. Rather than using pumice stones, enzymes are used to “eat” away at the indigo. Denim treated with an enzyme wash is stronger than those subjected to other washing techniques that experience higher level of abuse.
Filling Yard: AKA weft yarn. The yarns that run crosswise from selvage to selvage in a weave.
Finishing: The techniques and processes performed on a garment that gives it a unique chartered.
Five Pocket Jeans: The most common styles of jeans; they have 2 back pockets, 2 front pockets and a coin pocket in the right front pocket.
Garment Dye: When a garment is dyed as a finished garment. Unlike yard dye which takes place prior to the weaving of the yarn.
Hand: The way a fabric feels, a subjective judgement that decides if the fabric is suitable for the intended purpose. Many common adjectives: crisp, drapable, soft, stiff, cool, warm, hard, limp. The finishing process of a garment will affect the finished hand of a garment.
Indigo: Blue vat dye that was originally derived from the “Indigofera tinctoria” plant by fermenting the leaves of the shrub. In 1897, 14 years after Adolf von Bayer identified the chemical structure of indigo and became synthetically manufactured. Natural indigo has a slight red cast. Indigo’s inherent features include: strong color fastness to water and light, a continued fading and its ability to saturate and penetrate fibers completely.
Iro-ochi: Japanese term referring to the fading of indigo dye in denim. The term specifically relates to fading in exposed areas and not across the entire garment.
Jean: The term possibly derived from the French word “genes”. The term was originally used to describe the type of pants worn by sailors from Genoa. Historically, there are many people fighting over the distinct right of the inventor of jeans, denim and the process in which todays industry was created upon.
Laundry: a Laundry is a manufacturing company that takes unwashed jeans and processes them. The process includes: washing, stone washing, sandblasting, garment dyeing, and finishing; an example is a resin finish.
Left-Hand Twill: AKA an “S Twill”. A weave in which the grains run from the top left-hand corner of the fabric towards the bottom right. Usually in a piece-dyed fabric, left hand twill fabrics are woven from single piled yarns in the warp. Left-hand twills have a softer hand than right-hand twills after washing. FACT: The denim brand LEE has always used a left-hand twil as their basic.
Loop Dyed: One of the three major industrial methods of dyeing indigo yarns.
Mercerization: An industrial process used on yarn or fabrics to increase its luster and dye affinity. It can be used to keep the dye on the surface of the fabric or prevent dye from completely penetrating the fibers.
Microsanding: A fabric treatment process, in which a series of cylinder rolls in a horizontal arrangement, either wrapped with an abrasive paper or chemically coated with an abrasive are used to create a soft, sueded hand.
Open-end Spinning: A spinning process in which individual fibers are fed into a high-speed rotor shaped cup where they accumulate. Not all fibers are able to stand up parallel on the axis of the yarn, the yarns produced using this method are not as strong as ring-spun yarns of the same size.
Overdye: A fabric dying process in which additional color is applied to the fabric or garment to create a shade or color cast. “Dirty Denim” is an example of applying a yellow overdye. This is able to be localized process.
Oxidation: Occurs when oxygen and another substance chemically join. This happens in between bath dips of the the indigo yarn.
Pick: A single weft of yarn.
Pigment Dyes: Dyes that do not have an affinity for fiber an must be held to the fabric with resins. Creates a fabric that fades easily.
Ply: All yarns are a single ply unless twisted with another yarn. Piled yarns are used to make yarns stronger.
Pumice Stones: Volcanic stones used for stone washing garments. Before the use of pumice; rocks, plastic and shoes were used to wear down and soften denim during the laundry process.
Right-Hand Twill: AKA “Z Twill” The most common denim weave, in which the grain lines run top right-hand corner of the fabric towards the bottom left. Usually in piece-dyed fabrics right-hand twills use two plied yarns in the warp. FACT: Levi Strauss has always used a right-hand twill for its basic models.
Ring Dyeing: Describes a characteristic unique to indigo dye in which only the outer ring of the fibers in the yarn are dyed while the inner core remains white.
Ring Spinning: A spinning process in which fibers are fed onto the end of the yarn while it is in the “twisting zone.” 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 like unevenness, giving the jeans an irregular and vintage look. Ring-spun yarns add strength, softness and character to denim fabric.
River Washing: A washing process using a combination of pumice stones and cellulose enzymes to give denim a vintage, worn hand. The washer is loaded only with stones for the first cycle. Enzymes are introduced for the second stage in combination with stones and they are tumbled until the desired aged look is achieved.
Rivet: A metal accessory that is used for reinforcement of stress points as well as for non-functional ornamentation.
Rope Dying: Considered the best method of dyeing indigo yarns. The threads of denim are twisted into a rope, which is then fed through a sequence of being dipped into a bath of indigo dye, followed by exposure to air and then repeated.
Sanding/Emerising: A fabric finishing process where fabrics are sanded with sandpaper to make the surface soft without hair. It can be preformed before or after dying.
Sanforize: A pre-shrinking fabric process that limits residual fabric shrinkage to under 1%. Developed in the late 1920’s by the Sanforize Co., the process was used in 1947 to treat garments in Wrangler’s first denim line. the process includes the stretching and manipulation of the denim cloth before is it washed. Raw, unsanforized jeans will shrink 7-10% after the first wash and continue to shrink upto the third wash.
Sandblasting: a laundry process preformed before washing in which jeans are shot with guns of sand in order to abrade them and cause a worn appearance.
Selvage: AKA “Redline” or “Mimi” was originally called “self-edge” This is a 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. Old 28 to 30 inch shuttle looms produce denim where selvages are closed, whereas on larger modern weaving machines, the weft yarn s cut every pick, creating what is called a “fringe” selvage. FACT: Vintage Levi jeans began with an all white strip and later had a single redline strip along both selvages. Lee had a blue or green strip while Wrangler’s was yellow.
Shade Batching: The process of selecting batches of fabric into homogeneous shade lots to obtain consistent color continuity in the garment making.
Shade Blanket: Fabric is cut from each roll of fabric and sewn together with roll numbers on the back of each pad to allow manufacturers to wash and identify all shade colors of each roll. This is an important tool in cutting apparel made from denim to ensure that garments from the same shade group are cut.
Shed: During the weaving process, this is the opening formed by raising and lowering the warp yarns on a loom. The shed opening is what the weft yarns are passed through to complete the weaving interlace.
Shuttle: The device that carries the weft yarn across the loom in vintage shuttle looms. Selvage denim can only be woven using a shuttle loom.
Silhouette: Refers to the shape of a garment (i.e. bootleg, relaxed, skinny, low-rise, cargo…)
Sizing: Starch, gelatin glue or wax that is added to the fabrics in the finishing stage to improve the weight or touch and to help the fabric laying in the cutting phase. Denim generally has 1oz of sizing.
Skewing: Refers to the occurrence of twisting that happens when the fabric shrinks more perpendicular to the twill line along the twill line. Without compensating for this occurrence, the twill line will cause the right angles that the fabric is woven in to torque approx. 5 degrees after washing. To compensate for this, denim is skewed about 5 degrees in the same direction as the twill line to prevent the side seam from twisting toward the front of the jean.
Slasher Dyeing: One of the three main methods of dyeing indigo yarn.
Sliver: In the yarn manufacturing process, a sliver refers to the loose, soft, untwisted rope of cotton fibers that are produced using the carding machine.
Slub: Refers to the thick or heavy places in the yarn. Slubs are and other inconsistencies in denim produced on vintage shuttle looms. Modern yarn spinning technology is able to engineer these vintage looking textures into yarn in a pre-defined manner.
Stone Washing: A process that physically removed color and adds contrast. A 20-yard roll of fabric, generally 62in in width, is put into a 250 lbs washing machine along with pumice stones. The longer the denim and stones are tumbled the lighter the color becomes and the higher contrast is achieved. The denim is then rinsed, softened and tumble dried. FACT: Both Marithe & Francois Girbau and Edwin claim to have pioneered this technique.
Tate-ochi: Japanese term referring to occurrences of “Iro-ochi” forming in vertical lines in vintage denim. As the thread width is not uniform in vintage denim, the color fades the most where the thread is the thickest. This creates a faded thread of several centimeters along a single vertical indigo thread.
Twill: The diagonal lines formed by the weave.
Warp: The lengthwise vertical yarns woven into the weft yarns. They have more twist and are stronger then weft yarns.
Whiskering: A fading of the ridges in creases in the crotch area and the back of the knees, which gives the appearance of aged denim by way of years of “use marks”.
XX: The name originally referenced a particular model of Levi jeans built prior to 1890. 501 XX is Levi’s highest quality of woven Cone Denim.
Yarn Dye: Refers to fabric in which the individual yarns are dyed prior to weaving. Denim is yarn dyed fabric.
The denim dictionary will continue to be updated as technology advances and evolves. Please feel free to submit overlooked and emerging information to be added. This has been created by The Butt Therapist and inspired by the beautifully executed Denim Dictionary of The Denim Design Lab book by: Brian Robbins. Much of the data is quoted with an effective twist for your denim understanding.