textile science

11. KNITTING

 Knitting is the formation of a fabric by the interlocking of one or more sets of yarns. Knitting has been the traditional method of producing some items, such as sweaters, underwear, hosiery, and baby blankets. The trend towards a more casual lifestyle is reflected in the increased uses of knits in furnishings and apparel. A unique advantage of knitting is that a complete product can be fashioned directly on the knitting machine. Sweaters and hosiery are good examples.

                               Types of knitting

            There are two major types of knitting;

a)      Weft knitting:

·         It is a type of knitting in which yarns run horizontally from side to side across the width of the fabrics.

·         The fabric is actually formed by manipulating the knitting needles to make the loops in horizontal courses built one on top of another.

·         All stitches in a course are made by one yarn.

·         It is the simplest form as it can be made from one yarn.

·         Weft knits are made either flat or open width fabrics (like woven fabrics) on so called flat knitting machine

 

b)     Warp knitting

·         Warp knitting’s involves the preparation and use of a warp beam containing a very large number of parallel yarns mounted on the knitting machine.

·         The yarn run the length of the fabrics then the yarn forms the vertical loop in the one course

·         They move diagonally to the next wale to make a loop in the following course.

·         The yarn zigzags from side to side along the length of the fabrics.

·         Each stitch in a coarse is made by different yarn

                               Example of a weft and warp knit structure

Course: It is the total amount of horizontal rows in a knitted fabric

Wale: This is the total amount of vertical rows in a knitted fabric

 

The weft knitting is done using the following stitches;

            Purl knit/links & link stitch

·         It’s made by loops using needles on both ends

·         The fabric looks the same on both sides

Plain knit /flat knit/jersey stitch – It’s used for up hosiery and underwear’s and usually light in weight hence inexpensive

                 Rib stitch

·         Is done on hems of sweaters, necklines

·         Have good stretch ability

·         Has a high degree of elasticity

·         Are warm

               Disadvantages

·         High cost due to large use of fabric weight

·         Uses a lot of yarns

·         Low output since the machine used are slow

 

                   Interlock stitch

·         It is a variation of Rib stitch

·         It is thicker

·         It’s identical on both sides

·         High dimensional stability

                                         ASSIGNMENT

 Research and make short notes on knitting elements. (30 marks)

          Basic steps in knitting

·         Yarn supply

·         Knitting elements

·         Fabrics take down

·         Fabric collection

Advantages of knitted fabrics

·         They permits the fabric to stretching in any direction hence uniformity

·         They are warm because of the insulating air pockets contained in their construction

·         They are  porous and provides breathing

·         They are very absorbent, light in weight and wrinkle resistance

Disadvantages of knitted fabrics

·         If one loop breaks a hole is made and the whole fabric will run

·         Lose of shape (sagging)

·         They can easily shrink and this can be eliminated by using shrink prove finishes e.g. pat knit.

·         They are not wind proof

 

BONDING

Produces non-woven fabric by passing together a matt of textile fibers other than wool with the aid of an adhesive bonding agent. This is making a layered fabric using an adhesive binding agents or heat.

Bonding has come to include those fibers which are technically called laminated fabrics. These are composed of two separate layers of woven or knitted cloth fused together for improved stability, capacity and handling. Sometimes a thin shit of plastic form is fused between the face and backing fabric to add texture and insulation.

Characteristics of bonded fabrics

·         The presence of non-woven fabrics may be felt like paper like or very similar to that of woven fabrics

·         They may be too much thicker than or thin as a tissue paper

·         It may be opaque or translucent

·         They are warm

·         They do not fray

·         They are crease resistance

·         They do not drape

·         They are strong in all direction

LAMINATING

This is a non-woven method of fabric construction. It is a process of forming a fabric either woven or knitted to plastic form. Can be done using some wet adhesive whereby a water based acrylic compound is applied to the fabric followed by some heat which creates a permanent bond which creates a laminate. Could be done by use of a form flame whereby the flame I form of dust flame is used on the foam that will act as an adhesive

Characteristics of laminated fabrics

                    i.            Air permeability

                  ii.            Warmth retention

                iii.            Waterproof

                iv.            Stiff

                  v.            Durable

                vi.            Flexible

              vii.            Resistant to tear

            viii.            Resistant to stretching

                ix.            Waterproof

 

Uses of laminated fabrics

·         Rain coats

·         Automotive

·         Jackets

·         Carpets

·         In garments to provide reinforcement

FELTING

It’s the process by which textile materials are produced by matting, condensing and pressing fibers together. Felting is a method of producing warm, versatile though not very durable fabric of wool or fibers by the application of heat, moisture, friction and pressure. Felting depends in the natural abilities of wool fibers to shrink, coil or lock together to form a matt.

-          They can be made of natural fibers such as wool or animal fur or from synthetic fibers

 

                     Characteristics of felted fabrics

·         No warp, weft or selvedge makes it easy to use felt for garment construction.

·         Have good shock absorbency

·         Don’t fray since there is no system for threads or grain

·         Felts have no elastic or draping qualities

·         It can be cut and blocked into any shape

·         High thermal insulating properties make it retain/provide warmth.

·         Are good absorbers

·         Have good resiliency and will retain its shape unless subjected to undue tension

·         Excellent polishing agent-doesn’t wear

·         Since wool felts shrinks it should be dry cleaned only

 

Uses of felting fabrics

The properties of felts will affect it applications e.g. lack of tensile strength and durability limit the use of felts as a general fabric but it is especially applicable for:

·         Blocking/molding into hats.

·         Used to make carpets

·         Some are used to make hats

·         Used to make table mats

·         Light weight felts can be used to make blankets

·         Carpet under padding

·         Making slippers and shoes

 

NETTING AND LACING

It’s any textile in which the yarns are fused, looped or knotted at their intersections, resulting in fabric with open spaces between the yarns. Net is related to lace because many of the machine lace have generally shaped nets as their background.

A net is a geometrically shaped figure open mesh of fabric construction that is held together by knots and each point where the yarns cross one another (or interlacing)

A lace is an open work fabric made by threads usually formed into designs.

NETTING

Net is a geometric shaped figure open mesh made of silk, cotton, nylon rayon or other synthetic fibers. Come in different sizes of mesh and various heights. Machine made nets are closely related to warp knitting because it is closely constructed on either the tricot or raschel warp knitting machine. On the other hand net is related to lace because most of the machine made one have geometrical shapes at the back e.g. bobbin net- hexagonal shaped mesh or rayon, nylon, silk or cotton which is popular for evening dresses, veils, curtains and trimmings.

The knotted square mesh. The type with knots on all four corners to form mesh. Originally made by hand and used by fisher men and is now made by machines. Modern kind of fish nets are used for glass curtaining in contemporary living rooms, sun porches or den.

Characteristics of netting fabrics

·         They stretch

·         They are flexible

·         They are breathable

·         They have a pattern of knots

·         They are transparent

·         Remarkably tough and tear resistant

·         Flexible

Uses of nets

·         Used to make mosquito nets

·         Fishing nets

·         Luggage bags to create transparent, breathable compartments that allow people to store items

·         Used to make dresses

·         Volley ball nets

 

LACES

Laces were first made by hands and were highly priced as trimmings for apparels and as decorative pieces for the home. Usually beautiful and intricately designed laces are retained in some families as heirlooms and displayed in museums as works of art.

Linen yarn are generally used for expensive laces but cotton, silk, rayon and other yarns are used for other qualities and types. Lace may be made by knotting, looping, braiding, stitching and twisting. Machine made laces are made of the following machines.

Ø  Leaver’s lace – leaver’s machine was invented in 1813. It can produce the most intricate patterns from any type of yarn into fabric of up to 10 yards wide. The lever’s machine produces lace that are used in the dress making industry 

Ø  Nottingham – this machine produces coarser fabric than the levers and this fabric are large and used for the purposes such as table clothes

Ø  Bobbin – produced by the bobbin machine. It employs braiding principle. The lace produced has a fairly heavily texture with an angular appearance and a uniform count. It lacks the fine texture and flowing lines of laces produced by other machines.

Ø  Schiffli - produced by embroidery design. Although closely resembles a lace, it is produced by an embroidery technique on the Schiffli machine. This machine was developed in Switzerland and was named Schiffli meaning little boat because of the shuttle used. The technique uses 682-1020 needles to produce fine intricate designs in appliques and embroideries in all kinds of fabrics especially shear fabrics such as lawn and organdie. The finished material/fabric has the appearance of expensive hand work but will cost much less.

Use of laces

May be classified according to their uses

1.      All over lace – has design spread over the width of the fabric and repeated in its length and many kinds of designs and motifs and colors are used. The fabrics can be produced in widths of more than 1 yard that are devoid of scallops. Fabric comes in bold form and is used for blouses, dresses and evening wear

2.      Flouncing lace – come in 12” – 36” width and is used in ruffles. Has a straight top edge and is scalloped at the bottom.

3.      Gallon – has scalloped edge on the bottom and comes in widths of up to 18”. There is a bonded applique or fabric or as an insertion between 2 pieces of fabric.

4.      Insertion lace – could be sewn between 2 pieces of fabric or to the top and bottom edge of a single piece of fabric.

5.      Beading lace – this is normal gallon lace that has openings through which ribbons can be interlaced

6.      Edging – comes in widths of 18” or less and it has a straight top edge and a scalloped bottom. Use to form such garments as dresses, blouses and lingerie.

7.      Medallion lace – a single lace design that is used as applique on the ground fabric as for dresses, blouses, lingerie and napkins.

BRAIDING

This is a method of interlacing or plaiting three or more yarns or bias cut strips of clothes over and under one another to form a flat tabular fabric. This braided textured bonds which are relatively narrow can be used as belts, tapes for pajamas and some shoe laces. Some widths of plastic or straw braiding can be sewn together to make hat shapes. Similarly braids of fabric or yarns may be sewn together to make braided rugs. Braiding can either be handmade or machine made. The handmade is primarily for trimmings.

FRINGING

Fringing is a fabric construction technique where no sewing is involved; just simple knotting that is wrapped directly onto a finished edge.

Fringe originated as a way of preventing a cut piece of fabric from unraveling when a hemming was not used. Several strands of weft threads would be removed, and the remaining warp threads would be twisted or braided together to prevent unraveling. In modern fabrics, fringe is more commonly made separately and sewn on. Modern "add-on" fringe may consist of wool, silk, linen, or narrow strips of leather. The use of fringe is ancient, and early fringes were generally made of unspun wool (rather than spun or twisted threads).

MACRAME

Macramé is the art of decorative knotting, making chains, braids or fabric without aid of either hook or needle and with practically any string or yarn. Macramé is a form of textile produced using knotting (rather than weaving or knitting) techniques.

The primary knots of macramé are the square (or reef knot) and forms of "hitching": various combinations of half hitches. It was long crafted by sailors, especially in elaborate or ornamental knotting forms, to cover anything from knife handles to bottles to parts of ships.

Cavandoli macramé is one variety that is used to form geometric and free-form patterns like weaving. The Cavandoli style is done mainly in a single knot, the double half-hitch knot. Reverse half hitches are sometimes used to maintain balance when working left and right halves of a balanced piece.

Leather or fabric belts are another accessory often created via macramé techniques. Most friendship bracelets exchanged among schoolchildren and teens are created using this method. Vendors at theme parks, malls, seasonal fairs and other public places may sell macramé jewelry or decoration as well.

 

History

One of the earliest recorded uses of macramé-style knots as decoration appeared in the carvings of the Babylonians and Assyrians. Fringe-like plaiting and braiding adorned the costumes of the time and were captured in their stone statuary.

Arab weavers knotted excess thread along the edges of hand-loomed fabrics such as towels, shawls, and veils into decorative fringes. The word macramé is derived from the Arabic macramia, believed to mean "striped towel", "ornamental fringe" or "embroidered veil". Another school of thought indicates that it comes from Turkish makrama, "napkin" or "towel". The decorative fringes also helped to keep flies off camels and horses in northern Africa.

The Moorish conquest took the craft to Spain, then Italy, especially in the region of Liguria, then it spread through Europe. In England, it was introduced at the court of Mary II in the late 17th century. Queen Mary taught it to her ladies-in-waiting.

Macramé was most popular in the Victorian era. It adorned most homes in items such as tablecloths, bedspreads and curtains. The popular Sylvia's Book of Macramé Lace (1882) showed how "to work rich trimmings for black and colored costumes, both for home wear, garden parties, seaside ramblings, and balls—fairylike adornments for household and underlinens ."

It was a specialty in Genoa, and was popular in the 19th century. There, "Its roots were in a 16th-century technique of knotting lace known as punto a groppo"

Sailors made macramé objects while not busy at sea, and sold or bartered them when they landed, thus spreading the art to places like China and the New World. Nineteenth-century British and American sailors made hammocks, bell fringes, and belts from macramé. They called the process "square knotting" after the knot they used most often. Sailors also called macramé "McNamara's lace"

Macramé's popularity faded, but resurged in the 1970s for making wall hangings, clothing accessories, small jean shorts, bedspreads, tablecloths, draperies, plant hangers and other furnishings. Macramé jewelry became popular in America. Using mainly square knots and granny knots, this jewelry often features handmade glass beads and natural elements such as bone and shell. Necklaces, anklets and bracelets have become popular forms of macramé jewelry. By the early 1980s, macramé again began to fall out of fashion, only to be revived by millennials.

 

Tools and materials

Materials used in macramé include cords made of cotton twine, linen, hemp, jute, leather or yarn. Cords are identified by construction, such as a 3-ply cord, made of three lengths of fiber twisted together.

Jewelry is often made in combination of both the knots and various beads (of glass, wood, and so on), pendants or shells. Sometimes 'found' focal points are used for necklaces, such as rings or gemstones, either wire-wrapped to allow for securing or captured in a net-like array of intertwining overhand knots. A knotting board is often used to mount the cords for macramé work. Cords may be held in place using a C-clamp, straight pins, T-pins, U-pins, or upholstery pins.

For larger decorative pieces, such as wall hangings or window coverings, a work of macramé might be started out on a wooden or metal dowel, allowing for a spread of dozens of cords that are easy to manipulate. For smaller projects, push-pin boards are available specifically for macramé, although a simple corkboard works adequately. Many craft stores offer beginners' kits, work boards, beads and materials ranging in price for the casual hobbyist or ambitious craftsperson.

CROTCHETING

Crochet is a process of creating textiles by using a crochet hook to interlock loops of yarn, thread, or strands of other materials. The name is derived from the French term crochet, meaning 'small hook'. Hooks can be made from a variety of materials, such as metal, wood, bamboo, or plastic. The key difference between crochet and knitting, beyond the implements used for their production, is that each stitch in crochet is completed before the next one is begun, while knitting keeps many stitches open at a time. Some variant forms of crochet, such as Tunisian crochet and broomstick lace, do keep multiple crochet stitches open at a time.

 

Tools and Materials used in crocheting

Basic materials required for crochet are a hook and material that will be crocheted, most commonly yarn or thread. Yarn, one of the most commonly used materials for crocheting, has varying weights which need to be taken into consideration when following patterns.

Additional tools are convenient for keeping stitches counted, measuring crocheted fabric, or making related accessories. Examples include cardboard cutouts, which can be used to make tassels, fringe, and many other items; a pom-pom circle, used to make pom-poms; a tape measure and a gauge measure, both used for measuring crocheted work and counting stitches; a row counter; and occasionally plastic rings, which are used for special projects.

In recent years, yarn selections have moved beyond synthetic and plant and animal-based fibers to include bamboo, hemp, and banana stalks, to name a few. Many advanced crocheters have also incorporated recycled materials into their work in an effort to "go green" and experiment with new textures by using items such as plastic bags, old t-shirts or sheets, VCR or Cassette tape, and ribbon.

 

Crochet hook

The crochet hook comes in many sizes and materials, such as bone, bamboo, aluminium, plastic, and steel. Because sizing is categorized by the diameter of the hook's shaft, a crafter aims to create stitches of a certain size in order to reach a particular gauge specified in a given pattern. If gauge is not reached with one hook, another is used until the stitches made are the needed size. Crafters may have a preference for one type of hook material over another due to aesthetic appeal, yarn glide, or hand disorders such as arthritis, where bamboo or wood hooks are favored over metal for the perceived warmth and flexibility during use. Hook grips and ergonomic hook handles are also available to assist crafters.

 

-          Steel crochet hooks range in size from 0.4 to 3.5 millimeters, or from 00 to 16 in American sizing. These hooks are used for fine crochet work such as doilies and lace.

-          Aluminium, bamboo, and plastic crochet hooks are available from 2.5 to 19 millimeters in size, or from B to S in American sizing.

-          Artisan-made hooks are often made of hand-turned woods, sometimes decorated with semi-precious stones or beads.