Kawabata Evaluation system for Fabric (KES-F) is a systematic method of measuring the low-stress mechanical and surface properties of fabrics using very sensitive testing devices developed by Dr. Sueo Kawabata, Head of Polymer Chemistry at Kyoto University. These instruments are used for objective evaluation of hand value of fabric.
Use of KES-F:
To engineer the fabric
To Evaluate effectiveness of Different finishes on fabric
For automation in apparel manufacturing process
In quality control of fabrics and garments
KES-F contains four machines:
Tensile & Shear Tester: This instrument measures tensile properties by pulling the fabric in the direction of the warp and weft yarn. It also measures shear properties by pulling on the fabric at various angles to the direction of the yarn, causing the individual yarns to pull against one another as they would under normal use of the finished garments.
Pure Bending Tester: In the bending test, a fabric sample is mounted through a narrow slit and then the sample is bent, with which we can have precise values of bending rigidity and bending moment.
Compression Tester: In this instrument, a probe exerts force on a fabric sample to determine its compression properties.
Surface Friction Tester: In this instrument, the co-efficient of friction is determined by passing a metal probe over a mounted swatch of fabric. The second probe measures geometrical roughness.
Evaluation of Primary Hand Values and Total Hand Value depending upon End-use of the Fabric:
After testing on all the four KES-F instruments the system measures total 16 parameters in warp –way direction and 16 parameters in weft –way direction for woven fabrics. There are different fabric-categories mentioned below depending upon the end use of the fabric, on which basis Primary Hand Values and then Total Hand Value of the fabric is evaluated.
All the data are fed by the instrument in the equations depend upon the end-use of fabric and the calculation software automatically calculate primary handle values on 1 to 10 scale. 1 rating indicates poor result and 10 rating indicates excellent result.
Primary Handle Values:
Japanese termEnglish Equivalent
Fukurami Fullness & Softness
Hari Spreading / Antidrape
After calculating all the primary handle value by calculation software we can get one more parameter namely, Total Handle Value (T.H.V), which is rated on 1 to 5 scale. 1 rating indicates poor result and 5 rating indicates excellent result. So with the help of final parameter T.H.V we could obtain the behavior of fabric in totality.
Thermo Labo-II :
It is additional instrument with KES-F System to analyse
Minimum Fabric Length required for testing all the parameters is one square meter.
The sample size used for testing is 20cmX 20cm.
Please send the samples with warp & weft marking and face and back surface marking.
For Kawabata Evaluation, Please mention the end -use of fabric i.e. in which category handle value should be evaluated, whether it is for winter -suiting/shirting, summer-suiting/shirting or dress material or women's thin dress/suit/filament or knit outerwear/innerwear.
These information is required because the testing conditions have to be set up differently as per the end-use.
For Thermal Insulation, the sample size should be 25cm*25cm and Please specify the testing condition if any i.e. hot plate temperature (normally 35°c), velocity of air (normally 30 cm/s but we can set upto maximum air velocity 100 cm/s).