The purpose of this glossary is to help printshop owners, managers, printer operators, as well as anyone and everyone in the wide format inkjet printing industry to better understand the jargon used in inkjet printing for fabrics. This article was published in the Sign Africa Journal.
A
Acid dye textile ink, one of several special inks for inkjet textiles. Acid dye inks are for synthetic materials such as lycra, nylon, spandex, as well as natural silk, wool and leather. See also disperse inks and reactive inks.
Advantages and disadvantages of dye sublimation. Advantages are continuous tone, since the ink turns into a gas so there are no individual droplets that leave their trace. Downsides are that sublimated ink, on cloth, is great for some colours but lacks details in shadowy areas. The best results for soft signage would be produced by a graphic designer who knows which colours and which kinds of shapes look best printed on polyester by sublimation. If you wish to not use sublimation heat chemistry, you can consider pigmented ink (on cotton primarily), or reactive dye or acid dye ink workflow. Each ink chemister has its own slightly distinct workflow, and each has its own pros and cons.
Askewed or bias, fabric defect where filling yarns are not square with warp yarns on woven fabrics or where courses are not square with wale lines on knits.
B
Back fabric seam impression, backing fabric is often used to cushion fabric being printed. Fabric defect caused if there is a joining seam in the backing fabric, an impression will result on printed fabric.
Banding, bands of discrete colour or tone that appear when a laser toner printer cannot reproduce a smooth graduation from one colour to another. Instead there are noticeable jumps between one value and the next. Lack of registration or speed too far or not far enough.
Banding on inkjet is more complex; several kinds of banding may occur in wide format output. It is generally stated that most (but not all) banding results from clogged nozzles, especially on piezo print heads. Banding is most noticeable in areas of cyan or blue (such as the sky) or across dark solid colours. Banding may be worse in humid environments and on certain media. Dr Ray Work indicates another source of banding in piezo print heads is air bubbles inside the print head. He notes that any open ink system can allow nitrogen to get into the ink. Considering that he is the developer of DuPont chemical company’s inkjet ink programme, he definitely knows print head technology inside out. For more information on which printers are most prone to banding defects, see the FLAAR Report entitled: 'Piezo vs Thermal.'
Banding can also result when the media is fed too far, or not far enough (by even a millimetre; you get a dark band if fed not far enough; a light band if fed too far). Banding tends to increase when you try faster speeds.
Bias, a line diagonal to the grain of a fabric. A line at a 45 degree angle to the selvage is often used in the cutting of garments for smoother fit.
Birdseye, fabric defect caused by unintentional tucking from malfunctioning needle. Usually two small distorted stitches, side by side.
Bowing, fabric defect usually caused by finishing. Woven filling yarns lie in an arc across fabric width: in knits the course lines lie in an arc across width of goods. Critical on stripes or patterns and not as critical on solid colour fabrics.
Bulk ink system, usually means one litre or more of ink per colour.
C
Calendering unit or calendering machine, a machine that is used in the process of passing cloths between one or more rollers; usually under carefully controlled heat and pressure, in order to fix the colour on a printed fabric, or transfer an image from transfer paper onto fabric.
Charmeuse, a luxurious, supple, silky fabric with an extremely shiny face and a dull back, similar to satin but lighter in weight. Usually made from rayon or cotton, but premium varieties are made from silk.
Chiffon, made from tightly twisted crepe fibres, chiffon is lightweight, extremely sheer, almost transparent fabric that has a slightly bumpy texture.
Coating, is a chemical treatment, and is comparable in some regards to an inkjet receptor layer for materials to receive water-based ink. But coatings for fabric need to be different chemistry since each kind of textile ink is a bit different than water-based ink for an Epson or Canon printer. You generally buy the fabric already coated for the specific ink and fixing process that you know in advance you will use it for. The downside of coated fabrics is that they tend to cost more than uncoated materials.
Colour kitchen, when you use colour management and ICC colour profiles you can enter a sort of digital colour kitchen.
Colour smear, fabric defect as a result of colour being smeared during printing. Smearing is usually the result of a print head strike.
Cotton, although I always assumed cotton originated in Egypt, in reality it is a soft fibre that grows around the seeds of the cotton plant. This fibre can stand high temperatures and takes dyes easily. Cotton is most often spun into thread and used to make a soft, breathable textile.
Crease mark, fabric defect that appears where creases are caused by fabric folds in the finishing process. On napped fabric, final pressing may not be able to restore fabric or original condition. Often discolouration is a problem. Differs from crease streak in that streak will probably appear for an entire roll.
Crease streak, fabric defect that occurs in tubular knits. Results from creased fabric passing through squeeze rollers in the dyeing process.
D
Decor see also, interior design, interior decoration.
Dedicated fabric printer, would be a printer that is designed specifically to handle textile inks or fabrics. Examples would be StampaJet from DigiFab or textile printers from ATPcolour. The term dedicated fabric printer is used to distinguish these professional units from simple water-based printers that can handle paper-backed textiles.
Defect (within a long roll of fabrics), a fault that, if it were to appear in a prominent position in a garment or manufactured article made from the fabric, would readily be seen and objected to by an ordinary person who might contemplate purchasing such a garment or manufactured article in a retail shop.
Disperse dye inks, are for direct dye sublimation onto polyester inkjet textiles. Disperse dyes are for printing onto polyester and most synthetic fabrics, such as rayon or satin. Synthethic fibres: hydrophobic fabrics. After printing you need to sublimate the fabric to fix the colour. See also acid dye ink and reactive dye inks.
DPI (dots per inch), a measure of the output resolution produced by printers, imagesetters, or monitors. Dpi in the images themselves is actually pixels per inch (ppi) since of course there are no dots in an image on a monitor. So when you prepare a file, be aware that the dpi in Photoshop is not the same as dpi in the print head spec sheet. Plus, most dpi for printers may be a tad exaggerated. An image 150dpi (ppi) per full size you will print it is usually enough resolution in your file. Realise that the file format will impact the eventual quality and depends which RIP software you use. Some print shops favour one kind of file and other print shops favour others. I have found that most print shops want to crank your job out as fast as possible (usually resulting in low resolution for you).
Drop stitches, fabric defect that results from malfunctioning needle or jack. Will appear as holes or missing stitches.
Duck, also known as canvas. A tightly woven, heavy, plain-weave, bottom-weight fabric with a hard, durable finish. The fabric is usually made of cotton.
Dwell time, means how long do you keep the fabric inside the steamer, heat press or fixing unit.
Dye streak in printing, print defect that results from a damaged doctor blade or a blade not cleaned properly. Usually a long streak until the operator notices the problem.
Dye sublimation, is a chemical process whereby the final colour on the cloth is created from a liquid (the ink) imprinting on cloth or transfer paper and drying or curing to a 'solid'. The heat then turns the image (colour) into a gas (a vapour) to deposit its colour or merge the colour within the polyester. Sublimation usually requires the material to be polyester. You can also sublimate onto specially pre-coated ceramic tiles and aluminium, so dye sublimation transfer paper is not only for decorating textiles. Sublimating (dry) toner is similar but used mainly with desktop printers for simple tasks. You can print on transfer paper (with dye sublimation ink) and sublimate the image off the transfer paper onto your polyester. Downside is you need to buy a calendaring machine. You can print directly to the fabric with disperse dye ink and sublimate directly within the cloth with hot air (cheap way) or with heated cylinders (more sophisticated and potentially more even sublimation). In either case the ink sublimates: turns from a solid into a gas without going through another liquid stage.
F
Fabric, a cloth produced especially by knitting, weaving or felting fibres.
Finishing, with a regular inkjet print, finishing means trimming, laminating and/ or mounting. With an inkjet textile you may have to heat set (steam), wash out the excess ink. Like any other cloth that was just washed, you might wish to iron it too. But, if you select the newer fabrics, they don’t require steaming or washing, hence no ironing. But their longevity may not be as long. Steaming fixes the colours so they can withstand washing and dry cleaning.
Fire codes, dictate which fabrics may be used in public buildings and which not.
Fixation unit, a machine used to fix disperse dye ink colours onto the printed fabric, by using hot air and a roll-to-roll mechanism to transport the fabric into the machine.
Flag material, fabric used to print flags made out of polyester, knitted polyester or woven polyester.
Flax, a soft, lustrous and flexible fibre. It is stronger than cotton fibre but less elastic. The best grades are used for linen fabrics such as damasks, lace and sheeting. Coarser grades are used for the manufacturing of twine and rope.
Fray, to become worn away or tattered along the edges or a threadbare spot on fabrics.
Fumes, issue from a fixation unit, especially a grand format size (three metres and wider). You need a fume extraction system on all direct-to-fabric grand format dye sublimation printing systems.
G
Gauze, a thin, sheer fabric with a loose open weave that is usually made from cotton or silk.
Georgettes, a woven fabric created from highly twisted yarns creating a pebbly texture. It is thin and semi-sheer and is characterised by its crispness and exceptional strength.
Grommet(s), a large, metal-edged unit which surrounds a hole in a garment. The hole is used to put a rope or comparable material through to hang banners or signage.
H
Habotai, a Chinese Silk, plain weave fabric with a soft sheen. These silks do not add bulk but will add a slight amount of body and weight while remaining soft and fluid.
Hand, how the fabric feels to the hand or skin (if worn). You want a soft hand. If you use an ink not specifically for fabrics, the feel of the fabric is coarse and rough. Realise that each ink chemistry favours some colours and does weakly or inappropriately with a few other colours.
Heat press, a machine engineered to fix a design or graphic on a substrate by applying pressure and heat, such as a T-shirt.
Heat set, means in effect pre-shrinking the material so that when it is in the heat press dye sublimation system it won’t suddenly shrink. If a material shrinks during sublimation the design may become distorted.
High energy dye (disperse inks), better in most respects than low energy disperse dye inks, but high energy costs correspondingly more.
Hot knife, a tool with a heated blade used to cut media. It also refers to the properties of the fabric, can you hot knife the fabric easily, or not.
I
Inkjet, a printer technology where ink is squirted through nozzles onto the printer paper or other material to form an image or character.
Interior design, interior decoration is where kilometres of printed fabrics are used, as curtains, upholstery, etc.
J
Jacquard, a weaving method invented by Joseph Marie Jacquard, which involves a machine attached to a loom that can electronically select and control individual warp threads. The Jacquard loom is used to create intricately woven fabrics, including brocade and damask. Silk, polyester and rayon are commonly used in the Jacquard process.
Jerk-in, fabric defect 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.
K
Knots, fabric defect caused by tying spools of yarn together.
L
Linen, use reactive dye ink. A fabric made from linen fibres obtained from inside the woody stem of the flax plant. Linen fibres are much stronger and more lustrous than cotton. Linen fabrics are very cool and absorbent, but wrinkle very easily, unless blended with manufactured fibres.
Low energy dye (disperse inks). See also high energy dye (disperse inks). Low energy dye inks cost less and need less heat to sublimate (Work 2009:33).
M
Media, actually in this case singular and plural. Means any material coated with inkjet receptor powder. 90% of the material you put through an Encad, Epson, or HP is media. Also see substrate. The word media also has many other meanings in digital imaging.
Mesh fabric, is often defined as a loosely woven or knitted fabric that has a large number of closely spaced holes, frequently used for modern sports jerseys and other clothing.
Missing yarn, fabric defect which occurs in warp knit. Results from wrong fibre yarn (or wrong size yarn) placed on warp. Fabric could appear as thick end or different colour if fibres have different affinity for dye.
Mixed end (yarn), fabric defect that occurs when yarn of a different fibre blend is used on the warp frame, resulting in a streak in the fabric.
mm, does not necessarily stand for millimetre but for momme. Momme is a measurement of weight for silk.
Mottled, colour applied unevenly during printing.
Muslin, a sheer, lightweight cotton fabric that is produced mainly in India. This plain-weave material can be used as thin blankets or as a backing for quilts.
N
Needle line, fabric defect that is caused by a bent needle forming distorted stitches. Usually a vertical line.
Needlepoint, is a form of canvas work created on a mesh canvas. The stitching threads used may be wool, silk, or rarely cotton. Stitches may be plain, covering just one mesh intersection with a single orientation, or fancy, such as Bargello. Plain stitches, known as Tent stitches, may be worked as basketweave or half cross.
Nylon, polyamide, which can be made into a synthetic fibre. The first completely synthetic fibre developed in 1938. Known for its high strength and excellent resilience, nylon has superior abrasion resistance and high flexibility, high strength, elasticity, low water absorption and is quick-drying.
O
Oil based textile inks, may be compared and contrasted to water-based textile inks and solvent-based dye sublimation inks.
Olefin is polyethylene, strong man-made fibre giving resistance to abrasion and stain resistance. Good resistance to fading when solution dyed, very sensitive to heat.
Optical brighteners, are chemicals that attempt to make the material as white as possible.
Oversaturation, too much ink deposited onto a printed image, which causes the substrate to buckle.
P
Piezo-electric, the property of certain crystals that causes them to oscillate when subjected to electrical pressure (voltage). When the membrane oscillates, this movement forces ink out the nozzle.
Pigment inks, have pigments instead of dye molecules. Pigmented textile inks have better longevity but are noticeably less colourful (lack pop in most cases).
Polyester, PET, a polymeric material that can accept dye-sublimation or disperse dye direct fixation.
Polyester blend, a fabric resulting from the combination of polyester with two or more fibres within the same yarn. Fabrics are often made from blended yarns to increase durability, stretch, stain resistance and cost efficiency.
Pop, is jargon in wide format inkjet printing (and other graphic arts) for meaning that colours stand out. Sometimes it means that colours change from dull to bright and thus pop out, so to speak. But a colour that is bright from the beginning can also be referred to as pop.
You may tend to get colours that pop from full dye sublimation (printing first on transfer paper) than direct-to-fabric with disperse dye (whose resulting colours may not pop as much).
POP, If capitalised, POP can mean Point of Purchase (Point of Sale, POS), which means in-store advertisements directly in front of the merchandise that the store wishes to entice you to buy. Also used as POS.
Poplin, also called tabinet, this plain-woven fabric has a corded surface that runs selvage to selvage. Usually made from a silk warp with a weft of worsted yarn, but can also be made with wool, cotton, rayon, or any mixture.
Post-processing, might be considered comparable to the more technical print shop term ‘finishing'.
Pressure, is needed along with heat and/or steam to fix the ink colourants to the fibres. How much and what factors are determined by the kind of ink chemistry and whether or how the fabric has been pre-treated.
Print head longevity, all print heads eventually wear out, even piezo print heads. Some dye sublimation inks are rougher on print head longevity than other inks. So it is important to know whether the ink supplier has a warranty for print head life, or not. If a print head costs a great deal to replace, you should consider only ink that has a warranty, or at least an honest estimate of the print head life.
R
Raster Image Processor (RIP), produces an image defined as a set of dots/pixels in a column-and-row format.
Rasterisation, is the process of determining values for the dots/pixels in a rendered image. The placing of ink in a random pattern on a print that is pleasing to the eye.
Rayon, use reactive dye ink. A synthetic textile fibre made from cellulose. Rayon is known for its high absorbency, bright or dull lustre, pleasant feel or hand, good draping qualities, ability to be dyed in brilliant colours and superior strength.
Reactive dye inks, used to print onto vegetable derived fabrics like cotton or linen. Direct printing onto pre-treated fabric. The dye is absorbed by the fabric. See also acid dye inks and disperse dye inks for inkjet textiles. Needs lots of pre- and post-work (saturated steam and washing).
Runner, fabric defect caused by a broken needle. The runner will appear as a vertical line. Most machines have a stopping device to stop the machine when a needle breaks.
S
Sailcloth, a strong canvas of cotton, linen, or nylon in a plain weave, sometimes with a crosswise rib. Able to withstand the elements (rain, wind and snow).
Saturation, the amount of colour in a specific hue.
Scud-launcher steamer, is a vertical steamer. Looks like a launcher for scud missiles.
Scrimp, the result of fabric being folded or creased when passing through tender frames.
Selvage, the edge on either side of a woven or flat-knitted fabric so finished as to prevent ravelling. A narrow border often of different or heavier threads than the fabric and sometimes in a different weave.
Silk noil, raw silk. This is a slightly nubby fabric with random flecks in a natural, off-white colour. It has a somewhat rough texture and a gentle drape.
Sizing, a fabric finish that adds weight, stiffness, and firmness. The purpose of this is to make the yarn smoother and stronger to withstand the strain of weaving, to provide an acceptable hand in the woven goods, and to increase fabric weight.
Solvent inks, use aggressive chemical solvents instead of water. Due to environmental and health concerns, some companies have switched to lite solvents. Lite solvents come in several variants: one is simply less aggressive, the other is evidently an oil-based solvent ink.
Spandex, synthetic fibre made from polyurethane. It is lightweight, highly elastic, strong, durable and non-absorbent to water and oils. It can be repeatedly stretched over 500% without breaking, and will still recover to its original length.
Shrinkage, as the material is run through a steamer or heat fixation unit.
Steamer, many inkjet textiles need to be steamed, preferably under pressure, in order to set and pop the colours. Steamers come in several sizes and shapes:
• Stove-top steamer.
• Scud-launcher steamers ('vertical steamers').
• Moderate pressure steamer.
• Industrial production steamers.
Steaming paper, is used to keep the freshly printed fabric from sticking to itself as it is rolled to place into the steamer. With the vertical 3P steamer, a wire mesh is used instead of paper. This means it can be reused as often as needed. Steaming paper is available from Jacquard.
Sticky belt, is a transport belt (conveyor-like belt) with a glue-like material so that the weave of the fabric does not get pulled out of shape as it is pulled by the tension rollers through the printing system. In the world of UV-cured flatbed printers, any printer with a transport belt would not have glue, but otherwise the transport belt for a UV-curable flatbed printer is similar in drive mechanism of the belt. A transport belt adds anywhere between R265 ($20) and R397,000 ($30,000 ) to the cost of a printer (or less if made in China). But a low-cost transport belt may cause the material to feed improperly.
Stop mark, fabric defect caused when the loom is stopped. The yarn elongates under tension, when the loom starts again, the slack is woven into the fabric.
Stove top steamer, is just as the designation states: a metal cooker that you put on the stove top to heat. It is horizontal. The one from Jacquard can handle fabrics up to 91cm (36”).
Straying end, fabric defect on the warp knit. Caused when an end of yarn breaks and the loose end strays and is knit irregularly into another area.
Sublime, to turn from an ink (in theory a 'solid') into a gaseous state.
Sublimation-dye process, with wax or thermal ribbons, it is a printing process that uses special media consisting of a printer ribbon, a heated 'print head' and laminated printer paper. When the 'printer head' passes over the paper, the image is printed by varying the heat and causing colour (consisting of cyan, magenta and yellow) dyes to be passed on from the ribbon to the paper. Printers such as Matan and Summa use this, as does the desktop Kodak 8600 series printers.
Another form of dye sublimation involves printing with a regular thermal (Canon or HP) or piezo (Epson) printer on transfer paper. The heat press is subsequently applied to the paper on top of the material to which you wish to sublimate. The ink turns into a gas and penetrates the inkjet receptor. You end up with an image on ceramic tiles, solid metal, etc.
Synthetic fabrics, fibres elaborated to increase and improve the supply of natural fibres that have been used in making cloth. A few examples of synthetic fibres are rayon, acetate, nylon, modacrylic, olefin, acrylic and polyester.
T
Taffeta, with a smooth feel, and a crisp hand, taffeta can be made from a variety of fibres including silk and rayon. It has a subtle horizontal ribbing effect and provides lots of body and an ultimate rustle.
Technical textile is one whose extra strength allows it to be used for building wraps, billboard sized soft-signage, or car park tends. Yeong Jeou makes ARIA, a PE technical textile. If you wish for a more complete definition, try the 576 pages of Handbook of Technical Textiles, by Richard Horrocks and Subhash Anand, Woodhead Publishing, 2000.
Tensile strength of the textile is determined by the size (denier) and strength (tenacity) of the yarns and the number of yarns per linear inch or metre. The larger the yarn and the more yarns per inch, the greater the finished product’s tensile strength.
Tension roller (system), you can use either grit rollers against pressure rollers (for inkjet printers primarily for simple media and normal substrates). If you are using material that stretches, or is heavy, or has other features, you may prefer a more sophisticated system such as tension rollers.
Thermal transfer, a printer technology that uses heat to transfer coloured dye onto paper. Matan is a wide format printer using this technology.
Transfer paper, one major brand is Coldenhove; another is Beaver. Some ink chemistries work better on transfer paper than other textile ink chemistries.
Treated, see also untreated. A finishing process associated with the application of synthetic chemical compounds to the fabric to provide wrinkle-resistance, wash-and-wear characteristics, or an improved hand.
Trough, a kind of drainage that catches the ink that passes through some woven materials. This trough is the entire length of the platen and is directly underneath where the print heads pass over for each pass. To clean the trough, either there is a small drainage tube or you lay down absorbant paper towels or simply wipe up the ink quickly at the end of the day (before the ink solidifies). May also be called a gutter.
Tussah silk, is a plain weave silk fabric from 'wild' silk worms. It has irregular thick and thin yarns creating uneven surface and colour. Wild silkworms feed on leaves other than mulberry leaves. Tussah silk is similar to shantung, with silk from the wild. Colour is often uneven; usually referred to as 'raw' silk.
Twill, an incredibly versatile fabric distinguishable by diagonal ribs on its face, and a soft, smooth finish. Gabardine, serge, and denim are all examples of twill fabrics.
U
Untreated, see also treated. Usually but not always means treated polyester or untreated polyester.
UV cured inks, pigmented inks that dry instantly upon contact with UV light.
V
Viscose rayon, man-made synthetic fibre, typically referred to as rayon. Viscose has a silken, smooth feel and a terriffic drape, and is often used for linings and bridal garments.
W
Warp, the vertical threads in a particular fabric or on a loom.
Weft, the horizontal threads in a particular fabric or on a loom.
Wool, use acid dye ink. This textile is made using the fibres from the hair of animals, such as goats, sheep, camels, or llamas, and it comes in several different forms from crepe, to gabardine, to worsted. Wool is moisture absorbing and known for its warmth, and is also naturally stain and wrinkle resistant.
Wrinkle resistance, a fabric that has been treated to resist the formation of wrinkles.
With thanks to our friends at Sign Africa and Flaar Reports..
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