Legend Swimwear Factory Limited Product Evaluation Dr. M.Y. Leung Content (2 hours) 1. 2. 3. 4. Introduction of Product Evaluation Scope of Product evaluation Specifications of Swimwear Fabrics Fabric testing Fabric Construction Physical Properties Colorfastness Properties Labeling checking Performan ce Testing Scope of Evaluation Product Inspection Blindstitched hem Matching Pattern Workmanship checking Performance Quality of Textile Products C onstruction D urability A esthetic C are Functional & S a fe ty C om fort Fibre C om position Tensile S tre ng th A ppearance R etention D im ension S ta b ility W ater re p e lle nce T herm al P ro p e rty Fabric w eight Tear S tre ng th C olorfastness C olorfastness Flam m ability W ettability Fabric Thickness B ursting S tre ng th P illing R esistance A ppearance a fte r finishing Form aldehyre R e le a se M oisture R e g a in/ c o nte nt Fabric S ett S eam S tre ng th S nagging R esistance W eather/ O rg a nism re sista nc e O thers toxic or e nviro nm e nta l te st A ir/ w ater va p o r p e rm e a b ility Y a rn C o unt S eam S lip p a g e D ra p ing O the r Y a rn C ha ra c te ristic s A b ra sio n R e sista nce D im e nsio n S ta b ility H a nd le Performance Tests for Swimwear?? What suggestion for Care Label?? Swimwear fabrics Knits specializing on stretchable & functional knits Swimwear Fabrics Exit Pigment print, pigment discharge print, rubber print, burn-out print, puff print Back to Overall Products Stretch woven fabrics with Embroidery Exit Back to Overall Care-label for Swimwear Wash in warm water (40°C) Do not bleach Do not iron Do not dry-clean/ No dry-clean Do not tumble dry/ Flat dry/ Hang dry Specification and Standard Throughout the world there are numerous organizations to develop standard test methods and regulations to control the performance quality of textile. Uniformity of standards are with a growing need. International standards to alleviate some of the problems faced by manufacturers that export or import from foreign manufacturers are necessary. Sources of Standards Product Spec Company Standard National Standards International Standards International Standards International Used Standards: The International Organization for Standardization (ISO) British Standards (BS) American Association of Textile Chemists and Colorists (AATCC) Japanese Industrial Standards (JIS) European Committee for Standardization (CEN) What are the specifications for Swimwear? Are there any difference between swimwear and other knitted and woven fabrics? What make the difference? Specification for Knitted and Woven Beachwear (ASTM D 4154) Characteristics Requirement Knitted Breaking strength ASTM D5034 Bursting strength ASTM D 3787 (bursting attachment) Yarn slippage, 6mm (separation) ASTM D 434 Tearing Strength ASTM D 1424 Dimensional Change AATCC 135 Pressing and finishing After 5 launderings (shrinkage > 3%)testing stretch Growth ASTM D 2594 Colourfastness Burnt Gas Fumes – 2 cycles AATCC 23 Shade change from original fabric Shade change after 1 laundering 222N Woven 111N (25 lbf) - - 89N (20lbf) 6.7 N (1.5lbf) 2% max 3% max 1% max (pre-finished) 2% max (post-finished) 3% max 3% max Class 4 Class 4 Class 4 Class 4 Specification for Knitted and Woven Beachwear (ASTM D 4154) Characteristics Colourfastness Laundering: colour change AATCC 61 staining Crocking: Dry AATCC 116 Wet Perspiration: Shade Change AATCC 15 Staining Light (40 AATCC FU) (Xenon-arc) AATCC 16 Water: Chlorinated Fabric Appearance AATCC 124, AATCC 96 Flammability FFA Part 1610 Requirement Knitted Woven Class 4 Class 3 Class 4 Class 3 Class 4 Class 3 Class 4 Class 4 DP 3.5 Pass Class 4 Class 3 Class 4 Class 3 Class 4 Class 3 Class 4 Class 4 DP 3.5 Pass Specification for Knitted Swimwear (ASTM D 3996) Characteristics Requirement Test Bursting strength (Ball bursting) Dimensional Change Laundering Non-stretch Stretch Wet relaxation or growth Dry relaxation or growth Colourfastness Burnt Gas Fumes – 1 cycles - Shade change from original fabric and after 1 laundering cycle -Sodium Hypochlorite bleach -Non-chlorine bleach Laundering Shade change Staining ASTM D 3787 Requirement 30 lbf (133N) AATCC 135 5% max 7.5% max 10% max 5% max AATCC 23 Class 4 AATCC 188 AATCC 172 AATCC 61 Class 4 Class 4 Class 4 Class 3 Specification for Knitted and Woven Beachwear (ASTM D 4154) Characteristics Requirement Test Colourfastness Crocking: Dry Wet Perspiration: Shade Change Staining Sea water: Shade Change Ozone: Shade change Light (40 AATCC FU) (Xenon-arc) Flammability FFA Part 1610 AATCC 8 (solid)/ AATCC 116 (print) AATCC 15 AATCC 106 AATCC 129 AATCC 16 Requirement Class 4 Class 3 Class 4 Class 3 Class 4 Class 3 Class 4 Pass Buyer’s Specification for Knitted Swimwear Characteristics Test Mass per square meter Force & Elongation Dimensional Change (Drying tumble) Colourfastness Nitrogen Oxide Artificial Light Washing at 40°C Water Sea water Chlorinated water Perspiration Dry Rubbing Wet Rubbing Fibre Composition Requirement ISO 3801 ISO 5077 BS 4294 ±3% ±10% ±3% ISO 105G/01 ISO 105B/02 ISO 105C06 4/5 4 4 4 4 4 4 4 4 ¾ ±3% ISO 105E01 ISO 105E02 ISO 105E03 ISO 105E04 ISO 105X12 ISO 105X12 ISO 1833 What are the different between testing swimwear/fabrics and commercial apparel fabrics? Fabric with Stretch Most fabrics used for swimwear are elastic By insertion of Spandex/ Lycra etc. All elastic yarns are covered with a layers of fibres/ filaments Two ways of covering: airjet and wrapping Fabric Analysis Standard Conditions: Pre-conditioned: Stored the specimen in chamber with Temperature < 50°C Relative humidity: 10 to 25 % Conditioned: BS: 20±2°C and RH% 65±2% ASTM: 21±1°C and RH% 65±2% What types of tests are required to carry out in controlled condition? Fabric Analysis Standard Conditions: Pre-conditioned: Conditioned: BS: 20±2°C and RH% 65±2% ASTM: 21±1°C and RH% 65±2% What types of tests are required to carry out in controlled condition? Tensile Strength For fabric with stretch < 11% To obtain the breaking load and elongation at break of a textile fabric Grab test: 1-inch grab (ASTM D 5034, JIS L 1096, ISO 13934-2:99) Strip test: 2-inch strip test (ASTM D5035, JIS L 1096, ISO 13934-1) clamp 3 inches Grab Test Strip Test 200 mm clamp Tensile Strength Load and Elongation Curve Tearing Strength Tearing strength refers to the force required to break a group of yarns (max. up to 3 pieces) together by tearing off the fabric. There are various types of tearing depends on application. Tearing Strength Elmendorf Only for warp-direction of warp knit and woven ASTM D1424-96 JIS L 1096 Tongue Tear Single rip ASTM D 2261-96 JIS L 1096 Elmendorf Tearing Strength Criteria: The tearing strength must be within 80% of the centre capacity. What happen if the tearing load is at the 95% of the max loading? Release the weight to tear off the fabric Bursting Strength (most common for knitted fabrics) Bursting is radial or multi-directional breaking strength. There are two types of bursting strength: ball bursting and hydraulic bursting. Multi-directional force from a steel ball is push up the fabric held in flat until rupture. Multi-directional force from pressure of an inflated diaphragm is applied on fabric until rupture. Bursting Strength Bursting Strength Diaphragm bursting For knitted swimwear or woven swimwear with stretch > 20% ISO 13938-1:99/BS 4768, ASTM D 3786-87 Ballistic ball bursting For high strength fabric or high stretch fabric ASTM D 3787-80 Bursting Strength Radial extension Hydraulic diaphragm bursting Bursting pressure = P(f+d) - P(d) Fabric Stretch Stretched the fabric in defined load/ length Keep the stretched fabric for defined time Measure the change of L L Fabric Stretch and Growth Stretch = (L2 – L1) x 100% L1 L2: extended length under load L1: original length L2 L1 Fabric Stretch and Growth Growth = (L3 – L1) x 100% L1 L3: extended length after released L1: original length L3 L1 Dimensional Changes of Fabric after Home Laundering Dimensional Stability Maintenance of the shape and dimensions of a textile product can be a significant factor in its acceptance by consumers. Terminology: “Refurbishing” is used to describe any of a number of process that textiles may undergo to remove soil and stains and to restore the appearance of the items. Two most common refurbishing methods are “laundering” and “dry-cleaning”. Dimensional Stability Refurbishing A) Laundering It is based on the use of water as a solvent Water is effective in dissolving water-based spots and stains Detergents are laundering aids used to enhance cleaning B) Dry-cleaning It requires the use of organic solvents to dissolve oily soils and stains, such as body oils, waxes, fats and makeup Because only a minimal amount of water is used, fibres do not swell significantly and therefore, do not shrink as much. Dimensional Stability Dimensional stability refers to a fabric’s ability to resist a change in its dimensions. A fabric or garment may exhibit shrinkage or growth under conditions of refurbishing. Items are especially affected by the moisture and heat used in washing, tumble drying, and in steaming and pressing. There are various ways that need to shrinkage occur when textiles are subjected to heat and/or moisture. What are the causes of Dimensional Instability? Relaxation Shrinkage: Progressive Shrinkage Dimensional change that continues through successive washing Growth Results of relaxation of stress of fabric Shrinks in length results grow in width Yarn Reduction/ Thermal shrinkage It occurs in thermoplastic fibres. Upon imposition of heat, fabrics/polymer molecules move more randomly, nonlinear form and thus decrease the length Relaxation Shrinkage Dry state: Yarns are stretched and temporarily set. Release of strains Energy released Irreversible Need several washings to min & stable energy level. Causes of stretching (Woven) Warping Weaving Wet-finishing, dyeing printing etc. Causes of Extension (Knitted) Take-down tension of the knitting m/c Sewing or spreading of the knitted goods Fibre Level: Progressive Progressive Shrinkage Fibre Swelling Fibre movement within the textile structure What causes progressive shrinkage more serious? Alkaline medium Higher temperature Greater freedom of movement. How does fibre swelling would lead to fabric shrinkage? Fibre swelling Yarn swelling Balance of force If so, how to solve the problem of shrinkage due to fibre swelling? Contraction of Yarn Decrease in length of yarn Normally by heat/ high temperature Synthetic filament is most sensitive How to reduce the shrinkage situation? Dimensional Stability Shrinkage Measurement BS 5807/ BS 4923 AATCC 135 (fabric) AATCC 61 (garment) Report on 1st and last washes Benchmarks the length of 50cm or 25cm apart for both warp and weft directions Measure the dimension of products after treatment Shrinkage % = Original - after wash x 100% Original length Growth is positive Shrinkage is negative Dimensional Instability Results Interpretation For apparel products, the required maximum shrinkage or growth usually are dependent on types of products. For woven fabrics: usually maximum shrinkage after laundering is 2.0 to 3.0% For knitted fabrics: allowance for shrinkage is higher, usually 5.0% For stretch fabric: allowance for shrinkage will be higher. Colorfastness AATCC Definition of Colorfastness Resistance of a material to any change in any of its color characteristics, Transfer of its colorants to adjacent, or both after exposure to any environment Color Loss during daily uses Frosting Bleeding Fading Yellowing Crocking Color leaves the surface of fabric due to abrasion. (Detaches) Migration of color from wet fabric into water and then to others. Lightening of color due to loss or breakdown of dye. The change of color base to a very yellow version of a color. Transfer of a color to another surface through rubbing Bleeding piping 50 Color loss in drycleaning 51 Frosting 52 Light fading 53 Evaluation of Color change/ Staining (Visual Assessment) Gray Scale for Color Change Gray Scale for Staining Chromatic Scale Blue Wool Standard (Light Fastness) Gray Scale for Color Change Nine steps of color difference by stationary pairs of gray chips Half step rating 5 indicates no difference (two gray chips with same color) 1 indicates extreme difference Neutral gray = 12 ±1% Evaluation & Report 1) Grey Scale for Assessing Variation of Colour AATCC Test Method 15 – 2002: Gray Scale for Colour Change Fabric Sample Size: 6 x 6 cm Solution: Acid Perspiration GRADE * Original fabric colour Fabric colour after colourfastness perspiration test GRAY SCALE 5 No change as shown in Gray Scale, Step 5 4.5 A change as shown in Gray Scale, Step 4-5 4 A change as shown in Gray Scale, Step 4 3.5 A change as shown in Gray Scale, Step 3-4 3 A change as shown in Gray Scale, Step 3 2.5 A change as shown in Gray Scale, Step 2.3 2 A change as shown in Gray Scale, Step 2 1.5 A change as shown in Gray Scale, Step 1-2 1 A change as shown in Gray Scale, Step 1 *5 = no colour difference 1 = highest degree of colour difference Gray Scale for Staining Nine pairs of white and gray color chips. Half step rating 5 indicates no difference (2 white chips) 1 indicates extreme difference Rating is based on the color difference of the gradually increase darkness gray chip and the white chip Evaluation & Report 2) Grey Scale for Assessing Colour Staining Original colour of multifiber test fabric Multifiber test fabric colour after colourfastness perspiration test Multi-fibre Fabric Warp: Filament Dacron 55 Weft: multi-fibre fabric Acetate Cotton Nylon Polyester Acrylic Wool Evaluation & Report 2) Grey Scale for Assessing Colour Staining AATCC Test Method 15 – 2002: Colourfastness to Perspiration AATCC Chromatic Transference Scale Multifiber Test Fabric Solution: Acid Perspiration GRADE GRAY SCALE 5 Negligible or no color transfer 4.5 Color transfer equivalent to Step 4-5 on the Gray Scale for Staining. 4 Color transfer equivalent to Step 4 on the Gray Scale for Staining. 3.5 Color transfer equivalent to Step 3-4 on the Gray Scale for Staining. 3 Color transfer equivalent to Step 3 on the Gray Scale for Staining. 2.5 Color transfer equivalent to Step 2-3 on the Gray Scale for Staining. 2 Color transfer equivalent to Step 2 on the Gray Scale for Staining. 1.5 Color transfer equivalent to Step 1-2 on the Gray Scale for Staining. 1 Color transfer equivalent to Step 1 on the Gray Scale for Staining. Visual Assessment Method Light Sources: Daylight D-65 (North Sky light) White fluorescent/ UV Viewing angle: Specimen is 45° from horizontal Viewing perpendicular to the specimen Color fastness to Laundering Sewn the specimen to a white cotton fabric/ multifibre fabric Wash using the LaunderOmeter Assessment: Color change (Grey scale for color change) Staining (Grey scale for staining) Colorfastness to Laundering LaunderOmeter Wash Test ISO 105-C06 Test no. Temp pH . °C Liquor 4g/l Cl % detergent Sodium perborate No. of steel balls single 30 mins No. of steel balls multiple 45 mins A1 40 150 0 0 0 10 A2 40 150 0 1 0 10 B1 50 150 0 0 0 50 B2 50 150 0 1 0 50 C1 60 10.5 50 0 0 25 50 C2 60 10.5 50 0 1 25 50 D1 70 10.5 50 0 0 25 100 D2 70 10.5 50 0 1 25 100 D3 70 10.5 50 0.015 0 25 100 E1 95 10.5 50 0 0 25 100 E2 95 10.5 50 0 1 25 100 Color Fastness to Crocking Rub the fabric with a white cotton fabric 10 cycles in 10 seconds Dry rubbing Wet rubbing Assessment on mainly on staining Colorfastness to Perspiration/ Water/ Sea Water Perspirometer It is designed to determine the colour fastness of textiles to perspiration, water, sea water. BS 1006, BS EN 20105, ISO 105, AATCC 15 Procedures 1) Soak test 6 X 6 cm specimen in the perspiration solution for 30 ±2min. 2) Pass specimen through wringer 3) Weight specimen. Should be 2.25 ±.05 times the original dry weight. Procedures 4) Place assembled multi-fiber fabric & specimen on a glass plate. 5) Place the plates in the perspiration tester to provide uniform contact between the multi-fiber & fabric sample under a standard load. Then, secure the pressure plate 6) Heat loaded specimen into oven at 38ºC for 6hr 7) Place in conditioned atmosphere overnight (21ºC, 65% RH). Evaluation & Report 1) Grey Scale for Assessing Variation of Colour AATCC Test Method 15 – 2002: Gray Scale for Colour Change Fabric Sample Size: 6 x 6 cm Solution: Acid Perspiration GRADE * Original fabric colour Fabric colour after colourfastness perspiration test GRAY SCALE 5 No change as shown in Gray Scale, Step 5 4.5 A change as shown in Gray Scale, Step 4-5 4 A change as shown in Gray Scale, Step 4 3.5 A change as shown in Gray Scale, Step 3-4 3 A change as shown in Gray Scale, Step 3 2.5 A change as shown in Gray Scale, Step 2.3 2 A change as shown in Gray Scale, Step 2 1.5 A change as shown in Gray Scale, Step 1-2 1 A change as shown in Gray Scale, Step 1 *5 = no colour difference 1 = highest degree of colour difference Evaluation & Report 2) Grey Scale for Assessing Colour Staining Original colour of multifiber test fabric Multifiber test fabric colour after colourfastness perspiration test Evaluation & Report 2) Grey Scale for Assessing Colour Staining AATCC Test Method 15 – 2002: Colourfastness to Perspiration AATCC Chromatic Transference Scale Multifiber Test Fabric Solution: Acid Perspiration GRADE GRAY SCALE 5 Negligible or no color transfer 4.5 Color transfer equivalent to Step 4-5 on the Gray Scale for Staining. 4 Color transfer equivalent to Step 4 on the Gray Scale for Staining. 3.5 Color transfer equivalent to Step 3-4 on the Gray Scale for Staining. 3 Color transfer equivalent to Step 3 on the Gray Scale for Staining. 2.5 Color transfer equivalent to Step 2-3 on the Gray Scale for Staining. 2 Color transfer equivalent to Step 2 on the Gray Scale for Staining. 1.5 Color transfer equivalent to Step 1-2 on the Gray Scale for Staining. 1 Color transfer equivalent to Step 1 on the Gray Scale for Staining. Color fastness to Light Using the Blue Wool standard for assessment By grade ISO 105 B02 BS 1006 D01 By fading unit AATCC 16E Assessment for Light Fastness Measurement of Colorfastness to light for AATCC standard is measured the fading units. Specimen = grayscale G4, ? Step of bluewool it is? L2 L3 L4 L5 4 ? L6 L7 L8 L9 Assessment for Light Fastness Before exposure to the Xenon light source, the light source is required to be checked by the Blue Wool Standard Standard hours, specimen = Grayscale ? Step ? 10 to 40 hours Flammability standards for normal wearing apparel Standards Class 1: Normal flammability (suitable for clothing). Flame spread is 3.5 seconds or more for non-raised fibre fabrics Flame spread is 7.0 seconds or more for raised fibre fabrics. Class 2: Intermediate flammability. Flame spread is from 4 to 7 seconds and the base fabric ignites or fuses. Class 3: Rapid and intense burning (unsuitable for clothing). Flame spread is 3.5 seconds or less for non-raised fibre fabrics Flame spread is less than 4.0 seconds for raised fibre fabrics. Flammability Test (45°) Time required for the flame to proceed up to a distance of 5 in (127 mm) is recorded. The automatic timer can be stopped by breaking the stop cord at 5 inches length from the starting position. 45° Fire source Timer Cotton string END Product Evaluation