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PRESENTED BY: RUCHI BHUTANI

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  • PRESENTED BY:

    RUCHI BHUTANI

  • What is a Fabric Finish?

    A fabric finish is applied to a fabric once it

    has been made to improve its appearance,

    feel or other properties.

    Finishing processes are carried out to

    improve the natural properties or

    attractiveness of the fabric and to increase

    its serviceability.

  • Why are fabric finishes used?

    Fabric Finishes are used to improve the fabric in some way. This could be: improve the appearance - color, pattern or sheen.

    change the texture of the fabric - embossing, brushing or smoothing

    improve the feel - softer, crisper, firmer.

    improve the drape (how the fabric hangs) - weighted

    improve wearing qualities - crease resistance, stain resistance, flammability, waterproof etc.

    modify care requirements - easy wash, quicker drying times, colourfast, less shrinkage.

  • Provide aesthetic value

    Soften fabric or change the hand

    Adds to durability

    Adds to comfort

    Provide safety

    Improves performance

  • TECHNIQUES OF FINISHING DEPENDS ON:

    NATURE OF FABRIC i.e. chemical

    composition, state, weave etc. this

    determines the transparency, luster, fullness,

    weight, whiteness etc. i.e. the appearance

    PHYSICAL PROPERTIES OF FABRIC i.e. softness, stiffness, tensile strength,

    elongation, shrinkage property, insulation etc

    END USE OF MATERIAL- e.g. non shrinking,

    non-creasing, crease retention, draping,

    resistance to abrasion etc.

  • RECEPTIVITY OF FABRIC TO VARIOUS

    FINISHING OPERATIONS i.e. water, flame, rot

    proofing etc

    SUSCEPTIBILITY TO CHEMICAL MODIFICATIONS

    FINISHING OPERATIONS DIFFER ACCORDING TO

    THE PROPERTIES IMPARTED TO THE MATERIAL

  • Aesthetic finishes

    Functional finishes

    According to quality:

    Temporary

    Semi permanent

    Permanent

    According to the type of machinery

    Chemical finishes

    Mechanical finishes

  • The appearance of fabrics is sometimes deceiving. In part, the

    appearance depends on the type of fibers, the construction of

    the yarns and fabrics, and the dyeing and printing involved.

    However, finishes can be applied to fabrics that enhance the

    basic aesthetic qualities. Aesthetic finishes influence the luster,

    texture, drapability,hand and surface appearance of fabrics as

    well as enhance a host of other qualities.

    Aesthetic finishes change the appearance and/or hand or drape

    of the fabrics.

  • Lustre finishes produces a change in fabrics light

    reflectance by making them more shiny.

    Permanent or temporary changes in surface pattern and

    luster of fabrics can be achieved through a variety of

    finishing techniques.

    Techniques such as calendering, beetling, and burning-out

    influence the resulting appearance of the fabric.

    Calendering is a mechanical process that finishes fabrics

    by passing them between a series of rollers. By varying the

    rollers, adding any additional chemical treatment and/or

    temperature, a variety of calendered finishes result,

    including: glazed, cir, embossed, Schreiner and moir

    fabrics.

  • OBJECTIVE-

    To give soft and smooth surface to the fabric

    To give luster or glaze to the fabric

    To give silk like appearance

    To decrease the air permeability

    To flatten the slubs

  • In general calender usually have 2 to 7 rollers

    with more common being the 3 bowl

    calender

    Textile calender are made with alternate

    hard steel and elastic bowls

    The elastic bowls are made from either

    compressed paper or compressed cotton,

    however a lot of modern calender are made

    with a covering which is usually NYLON 6

  • 1,3 & 6 are hard rollers

    2,4,5 & 7 are soft rollers

    This provision is given so that there must be resiliency property in between two consecutive rollers so that compression remain uniform.

    Heating arrangement via steam circulation chamber

    The process parameters that can be controlled during the process of calendering are : SPEED OF FABRIC; SPEED OF ROLLERS; SURFACE OF ROLLERS

  • For light weight fabrics/cloth, less no. of

    bowls are used in calendering and for heavy

    weight fabrics more no. of bowls are used

    Different types of calendered effects are:

    SURFACE GLAZING

    CIRE EFFECT

    MOIRE EFFECT

    SCHREINEER EFFECT

    EMBOSSING EFFECT

  • Glazed fabrics such as polished cottons or chintz fabrics

    are created by saturating the fabric in a starch, wax or

    resin solution and allowing it to dry before calendering it.

    If starch or waxes are used, the finish is temporary and

    and if resins are used, the glaze is durable.

    The speed of the metal rollers is greater than the speed of

    the f/c.

    A 10 bowl calender is used for swizzing, when the

    production is very large and high glaze is required

  • Cir fabrics with their glossy or wet look are produced in a

    manner similar to glazing. Cir fabrics are coated with a

    wax or resin before being calendered with heated rollers.

    When thermoplastic fibres are used, the fiber surface that

    comes in contact with the metal roll melts and flattens

    slightly and produce highly polished f/c.

    Cire is a taffeta, satin or tricot, silk or silk blends f/c

  • Moir fabrics have a distinctive water marked look created

    in the calendering process.

    Moir is developed using either a moir embossing roller or

    a high compression calendering of two layers of ribbed-

    base fabric in a single pass.

    One popular method of preparing moir fabric involves

    using rollers that have been engraved with a design. The

    material is run between the engraved rollers with some

    sections of the fabric crushed to reveal the finished design

    that has a fluid or watery look. This type of application is

    often used to create material styles are ideal for evening

    gowns, formal capes, clutch handbags, and other types of

    formal apparel and accessories for women.

  • Another approach to achieving a moir fabric style is by using several

    different colors in printing fabrics, allowing the colors to overlap.

    The design achieves a sense of depth that varies as the eye travels

    across the pattern of the fabric. Because of the crushing of

    the fabric during the process, the color variation as the nap is

    brushed one way or the other will create a stunning effect.

  • Schreiner finishes on fabrics produce soft luster and hand

    by flattening the yarns and surface of a fabric through

    calendering.

    The schreiner calender has a metal roller engraved with

    200-300 fine diagonal lines per inch that are visible only

    under a magnifying glass.

    A schreiner finish is used on cotton sateen and table

    damask to make them more lustrous and on nylon tricot to

    increase its cover

  • Embossed fabrics have a pattern imprinted or embossed into the

    fabric. The embossed pattern is created by passing the fabric

    between a heated embossing roller and a shaped paper roll.

    Damask effect can be produced but the effect is temporary. It

    lasts longer on mercerised fabric.

    The degree of lustre may be modified by :- heating the chilled

    iron roll, pressure at the nip, speed of the m/c, moisture percent

    present in f/c etc.

    2-bowl embossed roller or 3-bowl embossed roller arrangement

    can be used.

  • Beetled fabrics have a smooth, lusterous linen look. In the

    beetling process, the yarns of the fabric are flattened as the

    fabric revolves around a drum while the surface is pounded with

    hammers.

    Burn-out finishes are created by applying chemicals that

    dissolve, burn-out or shrink parts of a fabric creating distinctive

    patterns. Acid designs are created by printing a chemical solution

    in a particular pattern. The acid, or chemical solution, causes the

    fabric to burn-out and become transparent rest portions remain

    opaque. Pliss has distinctive puckered areas. Puckering is the

    result of the application of chemicals on the base fabric, which

    causes portions of the fabric to shrink.

  • Finishes used to change the luster and texture of fabrics often

    have affects on the drapability and hand of the fabric. Yet, other

    finishes have been developed to directly affect the drapability

    and hand. Depending on the desired use, some finishes are

    intended to stiffen the fabric while others are intended to soften

    it.

    Drape finishes changes the way or fabric falls or hangs over a 3D

    shape.

    These finishes include:

    1. Parchmentizing

    2. Acid designs

    3. Burned out

    4. sizing

  • Crispness or body is given to cottons in the process of parchmentizing.

    Parchmentizing uses an acid wash (sulphuric acid) to make cotton almost transparent, and yet permanently stiff such as in organdy.

    Split-second timing is necessary to prevent weakening or tendering of the fabric.

    After the acid treatment, the cloth is neutralized in a weak alkali, washed and calendered to improve surface gloss.

    Several effects are possible: an all over, a localised, or a plisse effect.

    Because all over parchmentizing produces a transparent effect, sheer combed lawn is used. The lawn is singed, desized, bleached and mercerised. The fabric is then dyed, printed with colors that resist acid damage. Fabric is now immersed in acid solution and fiber surface is partially dissolved. This surface rehardens as a cellulosic film and when dry, it is permanently crisp & transparent. This all over treatment produces organdy fabric

  • In localised parchmentizing, if the design is a

    small figure with large transparent area, an

    acid resistance substance is printed on the

    figures and the fabric is run through the acid

    bath. The acid resistant areas retain their

    original opacity and contrast sharply with

    transparent background.

  • Burned out effects are produced by printing

    a chemical solvent on a blend fabric made of

    fibers from different groups such as rayon

    and polyester.

    One fiber is, usually less expensive or more

    easily dissolved fiber, is dissolved, leaving

    sheer areas.in case of rayon and polyester,

    rayon has been dissolved by acids.

    This finish is also known as ETCHED OR

    DEVORE because part of the fiber are

    removed by this subtractive finish.

  • In sizing or starching, the fabric is immersed

    in a mixture containing waxes, oils,

    glycerines & softners to or control fabric

    body.

    Gelatin is used on rayons because it is a clear

    substance that enhances the natural luster of

    fibers

    Sizing adds stiffness, weight and body to the

    fabric.

    Its permanance is related to the type of

    sizing,& method of application.

  • If the sizing is resin based and heat set, it

    will be permanent.

    If the sizing is water soluble, it will be

    removed during washing or it may create

    problems for consumers.

    Gelatin, e.g. may create a water spots on

    rayon if consideration or other water drops

    onto the fabric, these spots are difficult to

    remove.

  • Weighting is technique used to add weight &

    body to the fabric.

    A metallic salt such as stannous chloride is

    used,

    Salta that bond with the fiber are durable

    whereas others produce temporary surface

    coating.

  • The feel, appearance or consistency of a

    surface or a substance is known as texture.

    Texture finishes modify fabric texture or add

    components that completely change the

    fabrics original texture.

    Fabrics can be made smoother or rougher, or

    given textured patterns through a variety of

    means.

  • The finishes for achieving different textures

    are:

    1. Shearing

    2. Brushing

    3. 3D or raised embossing

    4. Pleating

    5. Flocking

    6. Embroidery

    7. Expanded foam

    8. Napping

  • Shearing is a process that evens out the length of the pile of fabric in a controlled manner i.e. Shearing is a procedure to remove surface fibers, yarn ends, knots and similar irregularities and surface flaws.

    During shearing the fabric passes through a series of tension bars and over an angled shearing bed. The prominent fibres are cut by blades, wound helically around a rotating cylinder against a stationery blade. Strong suction removes cut fibres.

    It may create a smooth surface or a patterned or sculptured effect by flattening portions of the pile with an engraved roller, shearing off the areas that remain erect , and steaming the fabric to raise the flattened and now taller portions.

  • Together with shearing, singeing is often used to

    control surface fibre, particularly for blends.

    During singeing, surface fibres are removed by

    an intensive flame or by reflected heat. Singeing

    is more invasive then shearing and penetrates

    deeper into the fabric than is possible by

    shearing, which is limited by fabric surface

    topography

    Shearing can be used to create raised patterns or

    to smooth the overall nap of a fabric.

  • Below is example of terry towel with and without

    shearing

  • Some sheared fabrics are also brushed. Fabrics are brushed

    to remove loose fibers, and in some cases, to direct the

    nap of the surface in a single direction.

    Common examples of fabrics with brushed finishes are

    brushed corduroy and brushed denim.

    Below is an example of denim twill (in red) with or without

    brushing.

    Also in white plain woven flannel with brushed finish.

  • The embossed design is permanent if the fabric has a thermoplastic fiber content or if a resin is used and heat set.

    Often used in combination with foil stamping, embossing is a process that alters the surface of paper stock or other substrates by providing a three dimensional or raised effect on selected areas. The procedure requires the use of two dies: one that is raised and one that is recessed. The dies fit into each other so that when the paper is pressed between them, the raised die forces the stock into the recessed die and creates the embossed impression. A specific level of pressure is applied to the dies in order to squeeze the fibers of the paper, which results in a permanently raised area in the paper.

    When the dies are produced, a die maker engraves the desired image into several metal plates, which are the embossing dies for use on an embossing press. A thorough understanding the process will enable a more successful result. Generally, embossing is the process most often employed to attract attention or convey a high quality textural contrast in relation to the surrounding area of the paper stock.

  • Below are the examples of 3D or raised

    embossing

  • A pleated fabric is made using a variation of embossing.

    Pleating is a highly specialized operation done by either the

    paper pattern technique or by the machine process.

    Puckered surface are created by partially dissolving the surface

    of nylon or polyester with phenol.

  • Plisse means to crease, to fold or to pleat. It refers to an intentionally wrinkled, pleated, or puckered fabric. The

    word can either be used to denote the finish of

    the fabric or the fabric itself. Plisse finish on fabric can be

    either temporary or permanent.

  • Two common methods of creating this fabric are through

    the use of a caustic soda, such as sodium hydroxide

    solution, or through tension weaving. Both processes

    tighten the fabric in the areas where the puckering or

    creasing is desired. Though usually found on finer fabrics

    such as cotton, nylon, rayon, or silk, other materials, such

    as wool and leather, can also be given a plisse finish.

    The alkali shrinks the fabric in the treated areas. As this

    shrinkage occurs, the untreated stripes pucker. shrinkage

    causes a slight difference in count between the two

    stripes.

    Plisse gives a similar effect of a seersucker fabric, but

    seersucker is achieved by different work tensions during

    weaving and is not a finish.

  • Texture can also be developed by adding fibers ( 5

    natural or synthetic surface fibers) in the finishing

    processes on the base fabric.

    Flocked finishes add texture by adhering short fibers to

    the surface of a fabric. Flocking can be used to create

    the appearance of a pile design or allover piles.

    Flock fibers attached to a fabric surface are very short

    and straight and are attached by an adhesive to create

    an inexpensive pile.

    The two basic methods of applying the flock fibers are

    mechanical and electrostatic.

  • MECHANICAL FLOCKING

    1. This process is called beater bar or gravity flocking system and is a mechanical process. 6-20 beater bars are used which are used to get fibres stand erect..

    2. The flocking fibers are randomly adhered to the surface of the substrate and all the fibres are adhered at different depths, creating an irregular flocked surface.

    3. Some fibers shedding occurs as the fibers are adhered and not penetrate or imbed.

    ELECTROSTATIC FLOCKING

    1. Flocking is the application of fine particles to adhesive coated surfaces. Nowadays, this is usually done by the application of a high-voltage electric field. In a Flocking Machine the "flock" is given a negative charge whilst the substrate is earthed. Flock material flies vertically onto the substrate attaching to previously applied glue. A number of different substrates can be Flocked including; textiles, fabric, woven fabric, paper, PVC, sponge, toys, automotive plastic.

    2. This process can also used to apply fibers on both sides.

  • The majority of flocking done worldwide uses finely

    cut natural or synthetic fibers. A flocked finish imparts a

    decorative and/or functional characteristic to the surface.

    The variety of materials that are applied to numerous

    surfaces through different flocking methods create a wide

    range of end products. The flocking process is used on

    items ranging from retail consumer goods to products with

    high technology military applications.

    As the fiber length increases, the denier also must increase

    so that the fiber will remain erect in the fabric. Fibres that

    are cut square at the ends anchor more firmly in the

    adhesive.

  • Embroidered finishes are machine or hand applied yarns

    added using satin or fancy stitches to create textured

    patterns.

    Machine embroidery uses compact zigzag stitches of

    various lengths.

    Two machines are used for embroidery: 1) shuttle

    embroidery machine 2) multihead embroidery machine

  • A coloured compound printed on the fabric

    expands during processing to give a 3D

    texture to the fabric.

    These foams are durable but create problems

    during pressing.

    It is commonly known as rubber print.

    Rubber like Neoprene, Nitrile, Viton, Natural,

    SBR, EPDM, silicone, Hypalone, Polyurethane,

    Teflon, coated fabric on fabric like Cotton,

    Nylon, Polyester, Fiber Glass, etc.

  • Nap is a layer of fiber ends raised from the ground weave of the fabric.

    Velvets, flannel, corduroy and satin are all examples of napped fabrics.

    The rich hand and surface texture of napped fabrics make them ideal candidates for luxury garments and design interest.

    There are ways to 'raise the nap', most of which involve wire brushes such as raising cards Originally, dried teasel pods were used and were still preferred for use on woolen cloth for a long time.Woollen fabrics, which must be damp when raising the nap, are then dried and stretched before the nap is trimmed or sheared. Cotton cloth goes straight to the shearing process, where the nap gets trimmed to ensure that all the raised fibres are the same length.

  • Napping is now done by pile rollers covered by a

    heavy fabric in which bent wires are embedded.

    Napping machines may be of single action or

    double-action.

    Napping is done on fabrics with low twist staple

    yarns.

    Gigging and raising may also describe the

    napping process.

    Gigging & raising process is applied to wool

    fabrics. The raised fibers of wet fabric are

    brushed in one direction which gives a smooth

    and lustrous appearance to the fabric.

  • FULLING/ FELTING

    1. Fulling is performed on wool fibres to improve their appearance, hand, thickness, softness, body and cover and the process is known as felting.

    2. Felt is made by a process called wet felting where the natural wool fibers, stimulated by friction and lubricated by moisture (usually soapy water), move at a 90 degree angle towards the friction source and then away again,

    3. fulled fabrics are denser and more compact in both warp and the filling directions.

  • Tufted finishes or decorations are created by

    sewing additional yarns to the surface of a

    fabric, creating a multi-dimensional

    appearance.

    Below is the example of tufted fabric with its

    face and reverse side.

  • Special finishes or functional finishes are

    those finishes that are applied to the fabric

    that makes it suited for specific uses.

    Various functional finishes are

    Waterproof finishes

    Water repellant finishes

    Flame retardant finish

    Moth proof finish

    Antistatic finish

  • Water proof finishes are those finishes which

    will not allow water to pass through

    regardless of the time exposure.

    These finishes also adversely affect the

    comfort property as they limit the passage of

    air

    These finish is coated with a resin, wax and

    oil etc.

    ASSIGNMENT- SEARCH FOR WATERPROOF

    FABRICS

  • Water repellant finishes are which resist the penetration of water into the fabric but permits the passage of moisture or air. If the fabric becomes very wet, water will eventually pass through.

    The principle is that it is coated with the repellant chemical which permits the passage of air and vapour between the interlacing in fabric.

    Water and the other liquid remain on the surface in small bead rather than spreading out and getting absorbed.

  • The chemicals used are silicones,

    fluorocarbons,paraffins etc

    Some chemicals used for water repellancy

    are also stain repellant.

    ASSIGNMENT- SEARCH FOR WATER REPELLANT

    FABRICS AND COMPARE WITH WATER PROOF

    FABRICS

  • These finishes play an important role on

    textiles by providing safety and giving escape

    time from a potential hazard

    When a fire starts flame, retardants reduce

    the flame spread and rate of fire

    development.

    Chemicals such as THTC- tetakis

    hydroxymethyl phosphonium chloride etc are

    used

  • These finishes re used to:

    Inhibit the growth of bacteria and other odor causing germs.

    Prevent decay and damage from perspiration

    Control the spread of diseases

    Reduce the risk of infection

    These finishes are also called anti-bacteriostatic, germicidal or antiseptic finishes

    These finishes are used for skin contact clothing, shoe lining, hospital items etc

  • Common chemical used is ziconium peroxide

    Exposure to ethylene oxide gas is also used

  • Moth silverfish etc attacks fiber like cotton

    Fluorine compounds, napthalene, DDT,

    paradichloro benzene etc are used for

    imparting moth proof finishes.

    They are available in crystal cake and spray

    form.

    Cellulosic fibers are also treated with boric

    acid to prevent the rapid growth of the

    mildew fungus etc.

  • Static electricity is produced or created when two non conducting surface such as synthetic textiles rub together.

    The two surfaces become oppositely charged and as the rubbing continues an electrical charge will build up.

    The wearer can experience the electric shocks and the fabric tends to cling to the body of the wearer.

    Anti static finishes are chemical substances applied to reduce and eliminate static charge

    It absorbs moisture from the atmosphere and thus reducing the dryness of the fabric that causes the static charge build up