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Textile Testing Methods Based on ISO Standard

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Md. Mustanzid Hasan Murad

Research Assistance, Textile Focus

What is Textile Testing?

Textile testing is a scientific test technique and method to evaluate whether the quality of textiles meets the requirements of the specified standards. Based on the use and conditions of textiles, influence on the product by the composition, structure, and properties of textiles, and determine the use value of textiles. When using textile products, everyone must hope that they have a good touch, good appearance, durability and should not contain harmful substances.

The Purpose and Significance of Textile Testing:

  • To check the quality and suitability of raw material
  • To monitor the production (process control)
  • To assess the quality of the final product
  • To investigate the faulty materials
  • To set standards or benchmarks
  • For research and development purpose
  • For new product development

Testing is governed by 5M, which are: Man, Machine, Material, Method and Measurement.

Basic Conditions and Method of Textile Testing:

1. Scope & principle of the test method

2. Conditioning, Sample preparation

3. Test procedure

4. Assessment/ Calculation

5. Report

Types of Textile Testing:

There are mainly two types of testing, one is routine process testing and another is quality record testing. The result of routine process testing can be got quickly in the working field. The result of quality record testing is to be recorded for different objects to finish the work.

  1. Fiber Testing:

In fiber testing, there are various properties of fiber have to be checked according to an end product. Mainly fiber testing is carried out in spinning and nonwoven departments. The required tests are for – Staple length, Fiber fineness, Strength, Maturity, Rigidity, Fiber Friction, Short fiber %, Trash content etc.

  1. Yarn Testing:

The yarn is raw material for fabric production so it becomes necessary to test the yarn for particular required fabric production. Parameters of yarn tested mainly are- Single yarn strength, Lea strength, CSP, Moisture regain, Hairiness, Friction, Abrasion, Twist measurement, Count and Yarn elongation.

  1. Fabric Testing (Woven, Knitted & Nonwoven):

The ultimate aim is to achieve optimum quality fabric. So to check whether the quality is achieved or not testing of fabric is done on- Tensile strength, Tear strength, Pilling resistance, Dimensional stability to washing, Seam slippage, Color Fastness (Washing, Rubbing, Perspiration, Light, Phenolic Yellowing, Saliva, Hot pressing), GSM, Abrasion, Drape ability or hanging property, Moisture %, Crease recovery and crease resistance, Stiffness, air permeability, Shrinkage etc.

All these testing is done after conditioning of material and in standard atmospheric conditions.

Factors affecting test results

  • The sampling
  • Atmospheric condition during testing
  • Methods of testing
  • Instruments used
  • Efficiency of the technician

Accreditation of Laboratory:

  • International Standards: ISO, IEC, GATT
  • Regional standards: CEN, CENEL, ASAC, PASC, ARSO
  • Chinese National Standard: GB/FZ
  • American National Standard: ASTM
  • American Association of Dyeing and Chemical Authors: AATCC
  • EU Standards: EN
  • Japanese Industrial Standards: JIS
  • Australian National Standards: AS
  • British National Standards: BS
  • French Standards: NF
  • German Standard: DIN
  • Korean Industrial Standard: KS

Different Types of Textile Testing Methods

Different buyers use different Textile testing methods. There are different types of Textile and Garments Testing methods such as –

  • American Society of Testing & Materials (ASTM)
  • American Association of Textile Chemists and Colorists (AATCC)
  • International Organization for Standardization (ISO)
  • European Norms (EN)
  • British Standards (BS)
  • British Standards for European Nations (BS EN)
  • DeutschesInstitut fur Normung (DIN)
  • Bureau of Indian Standards (BIS)
Some accreditation of laboratories worldwide

Some accreditation of laboratories worldwide

Common Test List of Restricted Substances: Phthalates, Formaldehyde, AZO Dye, Dimethyl Fumarate (DMF), Alkylphenols (APs) and Alkylphenol Ethoxylates (APEOs), Phenols: Pentachlorophenol (PCP) & Tetrachlorophenol (TeCP), Tributyltin (TBT) & Dibutyltin (DBT), PAHs (Poly Aromatic Hydrocarbons), Solvent/ VOC, Pesticides, Triclosane, Lead, NI- Release, Total Heavy Metal, ASTM F963.

Few common textile testing methods based on ISO Standard:

What is ISO?

ISO is an acronym that stands for the International Organization for Standardization. The term comes from a Greek word ISOS, meaning equal. The International Organization for Standardization is a group of people from many industries who work to create world-wide uniform industrial standards. The standards help insure that products, regardless of where they were made, are reliable, safe and of acceptable quality. In general, ISO standards cover considerations like regulatory issues and management systems. They assess a company’s ability to meet customer requirements and offer guidelines to improve performance. Within the International Organization for Standardization, setting ISO standards is done by technical committees related to specific industries. So, textile standards are set by an international committee composed of people who work in the textile industry. Today, textiles come from all over the world. They might be formed in one country, dyed in another, and made into finished goods in yet another. To ensure that the same practices are used in this complicated international process, many companies follow agreed-upon standards related to industrial processes and the goods produced by them. These standards are called ISO textile testing standards.

ISO Textile Testing Standards

image002As mentioned earlier, the textile industry is complicated. Around the world it employs millions of people. These workers follow many steps and use multiple processes to turn raw materials, including natural fibers like cotton and wool and synthetic or man-made fibers like polyester, into finished textile products like clothes and household goods.

Within the textile industry, following ISO standards can help to ensure consistent quality of the raw materials being used to make textiles, which in turn improves the final product. Adhering to ISO standards can also help lower operating costs and ensure quality management. Following ISO standards often involves inspection and testing at each stage of a process. For example, raw materials might be tested, then dyed fabrics, and finally finished goods. But ISO standards aren’t mandatory. They’re guidelines, and some companies only use them for materials and goods that are exported to places like the United States, where strict rules covering textile products and safety concerns are in place.

Dimensional Stability of Washing (ISO 6330: 2012)

Dimensional Change: A generic term for changes in length or width of a specimen subjected to specified conditions.

Scope & Principle of the Test: This international standard specifies method for the determination of dimensional change for fabric, garment or other textile articles when subjected to an appropriate combination of specified washing and drying procedure. The specimen is conditioned in the specified standard atmosphere and measured before subjection to the appropriate drying and washing procedure. After washing, drying, conditioning and measuring the specimen, the change in dimension are calculated.

Reference Standard & Terminology:

  • ISO 6330 Domestic Washing & Drying Procedure.
  • ISO 3759 Preparation making & measuring procedure.
  • ISO 139 Standard atmosphere for conditioning & testing.

Apparatus:

  • Washing machine type – A, Horizontal axis front loading type
  • Washing machine type – B, Vertical axis top loading agitator type
  • Washing machine type – C, Vertical axis top loading pulsator type
  • Automatic Tumble dryers
  • Electrically Dry heated flat- bed press
  • Line dry facilities
  • Conditioning racks
  • Domestic iron
  • Balance with appropriate measuring capacity
  • Dummy load
  • Indelible marker
    image003

    Automatic Tumble dryers

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Washing machine

Specimen Preparation:

Fabric:

  • Avoid minimum 1m from end of the roll or piece of goods.
  • Avoid minimum 150mm of the fabric from each edge.
  • Lay flat the sample without any tension before cutting the specimen.
  • Specimen size 500mm by 500mm.
  • Mark warp direction before cut out the specimen from the sample.

Conditioning: Conditioning specimen at least 4 hours as per ISO 139 prior to making & measuring.

Atmosphere: Temp – 20±2 °C & RH 65 ± 4 %

Test Procedure:

  • Weight the specimen and mix sufficient was load to determine the total two kg.
  • Place the material to be washed in the washing machine with dummy load.
  • Prepare appropriate dosage of reference detergent.
  • Select the washing program to be used for type A/ Type B/ Type C reference washing machine.

Dying Process:

Tumble dry: Clean the filter and place the test specimen and ballast in to the dryer and set the desired program and run up to dry.

Line Dry:

Hang each specimen by two corners with fabric length in the vertical direction. Hang in still air at room temperature not greater than 26°C until dry.

Drip Dry:

Hang each dripping wet specimen by two corners with fabric length in the vertical direction. Hang in still air at room temperature not greater than 26°C until dry.

For drying procedure of line and Flat do not allow air directly on specimens as it may cause fabric distortion.

Conditioning and Re- Measurement:

  • Conditioning the specimen for a minimum 4 hours.
  • Re measure and record the distance between benchmark.

Reporting:

The number & year of the international standard.

Dimensional change of length and width separately to the nearest 0.5% with a (-) sign or (+) sign for fabric.

Number of complete washing and drying cycles.

The procedure used for washing & drying from ISO 6330.

Determination of Fabric Propensity to Surface Fuzzing & to Pilling (Pilling Box Method)  

(EN ISO 12945-1: 2001)

Pilling Resistance: Resistance to the formation of pills on the surface of a textile fabric.

Scope & Principle: This part describes a method for the determination of the resistance to pilling and surface change in textile fabrics.

Specimen of the fabric are mounted on polyurethane tubes and tumbled randomly in a cork-lined box at a constant rotational speed. Fuzzing and pilling is assessed visually after defined period of tumbling.

Reference Standard & Terminology:

Fuzzing: Roughing up of the surface fibers and or teasing out of the fibers from the fabric producing visible surface change.

Pill: Entangling of fibers into balls the stand proud not fabric and are of such density that light will not penetrate and will cast a shadow.

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Pilling Test Box Machine

Apparatus:

  • Pill Testing Machine with Box
  • Polyurethane Specimen Tubes (Length 140±1mm, Diameter 31.5±1mm, Thickness: 3.2±1mm, Weight 52.25g±1 g)
  • Mounting Zig
  • Self adhesive polyvinyl tape 19mm width
  • Sewing Machine
  • Viewing Cabinet

Specimen Preparation:

  • Cut 2 specimen length direction and 2 specimen width direction from the sample, each 125mm by 125mm.
  • Mark warp direction.
  • An additional specimen of the same size is required for assessment.
  • Fold it face to face, two length wise and two width wise.
  • Sew 12mm from cut edges to form a tube.
  • Cut 6mm from each end.
  • Using the mounting jig, mount prepared specimen on each polyurethane tube.
  • Apply self- adhesive polyvinyl chloride (PVC) tape around each cut ends of specimen and leave 6mm polyurethane tube exposed,
  • Length tape on each end shall not exceed approximately 1.5 the circumference of the tube.

Conditioning: Conditioning specimen at least 16 hours as per ISO 139 after mounting on tubes.

Atmosphere: Temp – 20±2 °C & RH 65 ± 4 %

Test Procedure:

Clean the inside of the pill testing box and free from lint.

Place the four mounted specimens in the same pill testing box, close and firmly secure the lid.

Tumble the tubes in the box for the agreed number of revolutions

Remove the specimens from the box and remove the stitching from the seam.

Test Report:

  • Test method and year.
  • Mo of test specimens and observers.
  • No of revolutions.
  • Date of test.
  • Final grade assessed and whether it relates to fuzzing or pilling or both.
  • Details of any deviation from the procedure.

Tear Test of Fabric (ISO 13937-1)

Scope & Principle: This part of ISO 13937 describe a method known as the ballistic pendulum (Elmendorf) method for the determination of tear force of textile fabrics. The Specimen is fastened in the clams and the tear is started by cutting a slit in the specimen between and clamps. The pendulum is then released and the specimen is torn completely as the moving jaw moves from the fixed one. The tear force is measured.

image007

Tearing tester & Conditioning rack

Apparatus:image006

  • Tearing tester
  • Different capacity Load
  • Conditioning rack
  • Calibrated ruler

Conditioning: Condition specimen at least 4 hours as per ISO 139

Atmosphere: Temp – 20±2 °C & RH 65 ± 4 %

Specimen Preparation:

  • Avoid fabric selvedge at least 150mm
  • Specimen size as er template.
  • Take care of align the yars running in short direction parallel with the die such that when the slit is cut.

Test Procedure:

  • Place the specimen into the jaw and tighten the jaw as appropriately.
  • Using the built- in knife blade cut a 20mm slit.
  • Test the specimen as the required operation.
  • Record the result or reading from the scale.
  • If the reading is not between the 16 to 85 % of full scale range, change the load cell as appropriately.
  • No slippage of the threads out of the fabric.
  • No slippage in the jaw.
  • The tear is completed, Other results shall be discarded.
  • Remove the torn specimen and continue untill five tears have been recorded for each test.
  • Record the tear force.
  • Record if the tear was cross- wise, generally it is not applicable but if customer’s required so report by mentioning the cross tear.

Test Report:

  • Report the standard name and test method ISO 13937-1.
  • Elmendorf tearing strength for each test direction and testing condition, as requested.
  • Number of tests rejected because of crosswise tearing.
  • For computer- processed date, identify the program (software) used.
image008

Tensile Testing Machine

Tensile Strength Test- Grab Method ( ISO 13934-2: 2014)

Scope & Principles: This part of ISO 13934 specifies a procedure for the determination of the maximum force of textile fabrics known as the grab test.

A fabric test specimen, gripped in its center part by jaws of specified dimensions, is extended at constant rate untill it ruptures. The maximum force is recorded.

Apparatus:

  • (CRE,CRL or CRT type)
  • Clamps and Jaw Faces
  • Cutting device
  • Conditioning Racks
  • Calibrated Ruler

Conditioning: Condition specimen at least 24 hours as per ISO 139

Atmosphere: Temp – 20±2 °C & RH 65 ± 4 %

Specimen Preparation:

  • Avoid fabric selvedge at least 150mm
  • Specimen size-200mm by 100mm
  • Take specimen diagonally from the fabric
  • Specimen 5 for each direction.
  • Draw a line at 38mm ± 1mm along the long side of the specimen.

Test Procedure:

  • Front jaw 25mm by 25mm.
  • Back jaw 25mm by 50mm.
  • Gauge length 100 ± 1mm.
  • Test speed 50mm/min
  • Mark the inner side of the jaw and observe slippage.
  • Record any break within 5 mm of jaw.

If specimen slip or break at the edge of or in the jaw and result falls below normal average value discard the result and continue another specimen for obtaining the required no of specimen.

Calculate and Expression of Results:

Parameter Result Rounded to
< 100 N Nearest to 1 N
Breaking Force ≥ 100 N to < 1000 N Nearest to 10 N
≥ 1000 N Nearest to 100 N
Specialty If all the result are jaw break or five normal result can”t be obtained than the individual  result will be reported

Test Report:

  • Reference of the standard
  • Sample Indentification.
  • No of test specimen.
  • The arithmetic mean of the maximum force, in newton.
  • Any deviation from the given procedure.

Color Fastness to Rubbing (ISO 105X12:2016)

Scope and Principle: This part of ISO 105 specifies a method for determining the resistance of the color of textiles of all kinds to rubbing off and staining other material. This method is applicable to textiles made from all fibers in the form of yarn or fabric, including textile floor coverings whether dyed or printed. Two tests may be made; dry and wet rubbing cloth.

Specimens of the textile are rubbed with a dry rubbing cloth and with a wet rubbing cloth. The machine provides two combinations of testing conditions through two alternative sizes of rubbing finger, one for pile fabrics; one for solid color or large print fabrics.

Apparatus:

  • Crockmeter
  • Rectangular Rubbing Finger
  • Cotton Rubbing Cloth
image010

Grey Scale for Staining

image009

Crock meter

 

 

 

 

 

 

Specimen Preparation:

Fabric or textile floor covering:

  • Two pieces of not less than 50 X 140 mm for each dry and wet rubbing (Length & Width direction)
  • More specimen can be use for higher precision
  • For pile fabric, cut the specimen with the pile lay pointing in the long direction.

Yarn: Form a layer of parallel strands by wrapping it lengthways on a cardboard rectangle of suitable dimensions.

Conditioning: Conditioning specimen and crocking cloth at least 4 hours as per ISO 139 prior to marking.

Atmosphere: Temp – 20±2 °C & RH 65 ± 4 %

Test Procedure – Dry

  • Place a test specimen on the base of the crockmeter.
  • Then place the rubbing cloth on the rubbing finger by clip.
  • Run the machine for 10 sec or 10 cycle by to and fro motion.
  • Open the rubbing cloth from finger and place new rubbing cloth for another dry rubbing test.
  • Condition the rubbing cloth and remove fibrous material that might interfere with the rating.
  • Evaluate the staining by grey scale for staining.

Test Procedure – Wet

Weight the conditioned rubbing cloth.

Soak in grade 3 water, remove excess water and weight again to ensure 95-100% take- up.

Test by following the dry rubbing test.

image011

Light box arrangement

Assessment: Back each tested rubbing cloth with three layers of white rubbing cloth while evaluating.

Rate dry and wet crocking fastness by means of the gray scale for staining under the suitable illumination and record the numerical rating.

Reporting:

  • Reference to this part of ISO 105-X12
  • State whether dry or wet crocking test.
  • Finger and force were used in the test.
  • Whether dry or wet rubbing was performed along with the percentage of soak.
  • Time and atmospheric condition of conditioning.
  • Identification of the long direction of the specimen mounting, i.e. warp, weft or oblique.
  • The numerical rating.

References:

https://www.testextextile.com/what-is-the-textile-fabric-testing-test-method-test-item-classification/

https://textilelearner.blogspot.com/2012/02/textile-testing-objects-of-textile.html