Objective evaluation of fabric handle
The second part of KES was to produce a set of instruments to measure the appropriate fabric properties and then to correlate these measurements with the subjective assessment of the handle.
The system would enable an operator to measure reproducibly the total hand value of a fabric.
This system was known as the KESF system.
KESF system consists of four specialized instruments.
FBI Tensile and shearing
FB2 Bending
FB3 Compression
FB4 Surface friction and variation
These instruments are able to measure the tensile, compression, shear, and bending properties of the fabric together with the help of surface roughness and friction.
A total of 16 parameters are measured, all at low levels of force, which are intended to mimic the actual fabric The following types of quantities are measured by this system. deformations found in use.
 |
| KES- fabric handle |
Fabric property | Description | |
Tensile | LT | Linearity of load extension curve |
WT | Tensile energy | |
RT | Tensile resilience | |
Shear | G | Shear rigidity |
2HG | Hysteresis of shear force at 0.5° | |
2HG5 | Hysteresis of shear force at 5° | |
Bending | B | Bending rigidity |
2HB | Hysteresis of bending moment | |
Lateral compression | LC | Linearity of compression thickness curve |
WC | Compressional energy | |
RC | Compressional resilience | |
Surface characteristics | MIU | Coefficient of friction |
MMD | Mean deviation of MIU | |
SMD | Geometrical roughness | |
Fabric construction | W | Fabric weight per unit area |
To | Fabric thickness |
The tensile properties are measured by plotting the force-extension curve between zero and a maximum force of 500gf/cm (4.9N/cm), the recovery curve as the sample is allowed to return to its original length is also plotted to give the pair of curves.
 |
| Force VS Extension tensile strength |
From these curves, the values like tensile energy, linearity, and resilience are calculated.
Tensile energy WT = the area under the load strain curve (load increasing)
Linearity LT = WT / area triangle OAB
Resilience RT = area under load decreasing curve / WT * 100%
The compressional properties are measured by placing the sample between two plates and increasing the pressure while continuously monitoring the sample thickness up to a maximum pressure of 50gf/cm (0.49 N/cm ).
Questions -
- What is the objective evaluation of the fabric handle?
- Which fabric properties are measured on KES?
- Draw a graph between force and extension tensile strength.
References
Booth, J. E. :. (n.d.). Principles of textile testing an introduction to physical methods of testing textile fibres, yarns, and fabrics. London: National Trade Press Ltd,1961. from https://www.abebooks.co.uk/Principles-Textile-Testing-Introduction-Physical-Methods/19989810376/bd
Cenote, M. (2015). Google Books. In The SAGE Guide to Key Issues in Mass Media Ethics and Law (pp. 847–858). SAGE Publications, Inc.
Ferreiro López-Riobóo, J. I. (2015). Long-term (2001–2012) study of a proficiency testing scheme for textiles. Accreditation and Quality Assurance, 20(4), 239–245. https://doi.org/10.1007/s00769-015-1128-1
Further reading
Part-1 Fabric Objective evaluation methodology - Kawabata system
Part-2 Objective evaluation of fabric handle - KES second part
Part-3 Fabric Objective evaluation methodology - FAST system
Part-4 Fabric Assurance by Simple Testing 1 to 4
Writer - DSPAT Team
