Some considerations on using a different range of flexible

substrates – such as fibres,fabrics, non-woven or foams

Charles A BishopC.A.Bishop Consulting Ltd

www.cabuk1.co.uk

CONSULTING LTD

Prototype of a winter outdoor jacket with ipv. This jacket was developed by Maier Sports6,

with support from the Institut fürPhysikalische Elektronik andother partners in the German

SOLARTEX project7. The jacket was first presented in Munich at the International Trade Fair For Sports Equipment & Fashion

(ISPO) in January 2006. It comprises nine amorphous Si

solar modules from Akzo Nobel8 with a maximum power output of

2.5 W under full sun.

Since thesemodules are designed for long-term outdoor stability, the final

laminates are comparatively rigid and not suitable for large-area

clothing integration.

Options

Use a fine wire included in the twisted fibre bundle Wrap a fine wire around an existing fibre bundle

Coat a monofilament fibre & add to bundleCoat a multifilament fibre bundle

Coat a film – micro-slit & twist to make fibre/yarn

Use any of above to make a fabricDirectly coat a woven or non-woven fabric

Add fine wire to weave – e.g. sensors – switches - connections

Add coating to woven/non-woven fabric or foam – EMI/RFI screening

Directly coat woven/non-woven materials - Ag for medical dressingsDirectly coat woven materials – heat reflecting clothing

Hook: 1.8 Ohm per sqLoop: 1.4 Ohm per sq0.8 Ohm through mated closure

Expected cycle life: 5000 openings/closings

Woven electric fencing tape

substrate

aluminium metalised

Coloured laquer over metal

metalised film microslit Microslit film used as flat thread e.g.

as in security threads for banknotes

If microslit film is twisted it will form

a tight tube or thread/yarn that can be used for

sewing of weaving fabric

Coat film – micro-slit & twist - metallic yarn for sewing

MetallizedHolographic

Yarn

Electrical properties of metal monofilaments fibers

(a) Twisted metal wire: The metal wire is twisted around the polymer yarn; (b) Metal coating: The polymer yarn is physically/chemically coated with a thin metal layer; (c) Metal fibers: The conductive yarn consists of metal multifilaments

Standard design of copper yarn twisted with

polyester fibers;

Teijin

Octa ™50% wtof solid

fibre

SEM image of the polypyrrole coated textile

(a) (b)

Wearable Electronics and Smart Textiles: A Critical Review Matteo Stoppa & Alessandro Chiolerio

Sensors 2014, 14, 11957-11992; doi:10.3390/s140711957

Dr Tilas Dias Univ Manchester

Woven non-woven

The substrate may not be optically denseTo prevent coating the deposition drum a free span deposition process should be considered

Sidrabe

Forcespun PEO nanofibres

SEM image of Ag coated Nylon 6 forcespun nanofibers.

D. Mihut et al SVC 55th Ann. Tech Conf Proc, p 725

Smith & Nephew - Acticoat

Controlled diffusion

Moisture from wound into dressing

Ag ions from dressing to wound

Cu on ripstop nylon

This fabric touchpad was inspired by the properties of piezoresistive materials to measure both amount of pressure applied through the materials and increase of resistance across distance. It is made by layering piezoresistive material between two conductive layers and using the piezoresistive layer to alternatively measure position and pressure. Instructable >> http://www.instructables.com/id/EJKTF3WGV490JGK/

(doped polyprrol coated fibres)

iSkinTouch Sensing:

(a) Overview of layers in a touch-sensitive iSkin; (b) sensing without touch contact; (c) projected capacitive sensing of slight touch events; (d) resistive sensing of firm touch events

Luminex Spa, Prato, Italy

Dr Tilas Dias. Univ Manchester

500 µm

1D

2D

500 µm

R. Xu et al. Extreme Mechanics Letters 1

(2014) 120–126

eg. ultrasoft silicone based adhesive

eg. Lycra

1D system stretched to elastic limit

Experimental and FEA results of a four-island chain

(a) mounted on a substrate with 30% prestrain

(b) after prestrain release

(c) stretched to the elastic limit. The colour denotes the maximum principal strain in metal.

The scale bars are 500 μm.

IMEC-Univ GentCMST Belgium

2013

Electronic devices with extending linking

connections deposited onto rigid substrate then

encapsulated with silicone or polyeurethane and transferred to fabric

laminated with pliable high adhesive

IMEC-UGent - Cmst 2013

Electronic devices with extending linking connections deposited onto rigid substrate then encapsulated with silicone or polyeurethane & transferred to fabric laminated with pliable high adhesive

Fibres may be opened up and then if it is passed through a

plasma the surface may be treated or a coating deposited

If the pressure is increased the mean-

free-path is shorter & the plasma can

penetrate into the centre of the bundle

fibres plasma

At contact points there will be

friction & abrasion

Wet coatings will glue together points of contact preventing damage but also

preventing movement & stretch, limiting flexibility & drape

Individual fibres are spun into yarn

Coating adhesion to the fibres has to be good to enable the bending required to knit or weave the yarn into a fabric and then to allow the fabric to be stretched, folded or creased.

Free spandeposition

face to faceopposing

magnetronsputtering

sources

unwind

rewind

Chillroll

Chillroll

NS

N

NS

N

Cooled drum

Protective film

Fabric

Heat transfer coefficient (HTC)

between drum & film

HTC between film & fabric

NSN

Cooled deposition

drum

If the opposing magnetrons havetargets of the same material thenstray material passing through

the fabric will be deposited on theopposite magnetron & re-sputtered

The process limitation is usually thetolerance to heat of the substrate

The protective film is disposable & so cleaning can be relatively quick & edge shields may be reduced in size or eliminated. The process will also be limited by the

heat load onto the substrate.

Schematic of Atomic Layer Deposition (ALD) on fibres

PUMPS

Fibre

Gas 2 input

Buffer zone

Gas 1input

PUMPS

PUMPS

PUMPS

High pressure process –short mean free path = greater coverage

Carpeting – clothing – shoe inserts – tyre reinforcement - energy harvesting / sensors

Development of Textiles for Electrical Energy

Generation and Storage(european FP7 project)

Hybrid Piezo Photovoltaic (HPP) films and fibres

Prof.Elias Siores - University Bolton, UKD. Vatansever et al. ‘Hybrid Photovoltaic-Piezoelectric Flexible Device for Energy Harvesting from Nature’ Adv. Sci. Technol. 2013, 77, 297-301

Gyu Cheol Yoona et al, KoreaNano Energy(2015) 12, 547–555

Conclusions

• There is an opportunity to produce functional or smart fibre or fabrics.

• This includes energy harvesting, energy storage, sensors, lighting, switches & other electronic devices & medical coatings, often starting with conducting fibres or fabrics

• Many devices will require a combination of atmospheric and vacuum coatings

Thank you

Any questions?