Examples of smart textiles Flashcards
Name 3 applications for photochromism on textiles
UV exposure
Security printing/ brand protection
Design effects
Explain how chromic materials work.
- stimulus is applied to dye colour 1, changing it to dye colour 2
- stimulus is removed, reverting it back to dye colour 1
Name 3 applications for thermochromism in textiles
- Temperature warning signals
- Textile thermometers
- Design effects
How do the shape memory materials (SMM) work?
They are materials that will change shape in response to stimulus (usually heat), but revert back to their previous memorised shape when stimulus is removed.
Name what applications Shape memory material can be used for
Smart garments
Smart curtain
Medical: Tweezers, Teeth braces, Artificial muscles Fasteners, clips
Switches
What are the three ways of generating electricity in textiles that have been explored?
- light harvesting materials (photovoltaics-solar cells)
- use of body heat (thermocouples)
- mechanical motion (piezoelectric materials)
Name the practicality issues of incorporating photovoltaics into garments
• Area of photovoltaics required, positioning on the garment
• Pliability
• Method of mounting and connectivity to devices – conducting fibre, soft switch
• Durability in use (laundrability, stress)
• Problems due to variability of sunlight (day-to-day and with latitude), efficiency of
conversion of solar energy into electrical energy.
Would thermocouples be effective in textiles?
Indication of power generation possible, but general ineffectiveness of present
thermocouple devices to convert body heat to electrical energy.
Would piezoelectric materials be effective in textiles?
Explanation of principle of operation. Indication of power generation possible, and of very
limited range of piezoelectric materials available. Only very low power generation possible.
Are photovoltaics effective in textiles?
Indication of power generation possible and of power requirements of devices such as MP3
player, mobile telephone, etc.
Name the methods by which textile fibres can be made for conduct electricity
- metallic wires
- coated textile fibres
- inherently conducting textiles
What are the advantages and disadvantages of using metallic wires to conduct electricity in textiles?
excellent conductivity, but generally heavier than textile based fibres, not as
flexible, and they are abrasive.
What are the advantages and disadvantages of using coated textile fibres to conduct electricity in textiles?
e.g. nylon or polyester coated with either a thin metallic layer or a layer of
conducting textile materials. High conductivities possible, but the coating may crack or peel away during use or laundering, reducing conductivity.
What are the advantages/disadvantages of using inherently conducting textiles for conducting electricity in garments?
e.g. polypyrrole, polyaniline types. Reasonably good “textile” properties.
Conductivity is lower than copper or silver, but still good enough. Black colour.
How do thermoelectric generators work?
- they turn a temperature difference into an electrical flow
- still experimental
How do piezoelectric materials work?
When pressure is applied, a voltage is induced across the material
What are the 2 main groups of piezoelectric materials?
- ceramics
- crystals (e.g quartz)
