Nonwovens for technical applications

NONWOVENS FOR

TECHNICAL

APPLICATIONS

Infoday. April 22nd, 2015. Gaziantep

(Turkey)

Oscar Calvo

R&D Group on Textile

Finishing, Health and

Environment

1. INTRODUCTION TO AITEX’s RESOURCES ON NW TECHNOLOGIES

2. NONWOVEN MANUFACTURING TECHNOLOGIES

3. MARKET TRENDS FOR TECHNICAL APPLICATIONS OF NWs

4. CASE STUDIES AND SUCCESSFUL STORIES

5. CONCLUSIONS

Infoday. April 22nd, 2015. Gaziantep (Turkey)

Nonwovens for technical

applications 2

SUMMARY


When nonwovens are involved in textile applications, in most cases

some auxiliary processes are also required (technical finishing

processes/technologies), and some of them are available at AITEX:

3

Coating

Lamination / bonding

Surface treatments

Electrospinning


applications Infoday. April 22nd, 2015. Gaziantep (Turkey)

Air-laid

Wet-laid

Nonwoven-based

technical application


2 main technologies are available for lab trials and testing of new

fibers for innovative nonwovens:

4



Nonwoven production (lab scale)

Air-laid technology: very short fiber material can be applied.

Wet-laid technology: dispersion of the short fibers using water.

Our pilot plant can apply wet finishing on textiles by padding

(impregnation) or by knife coating (on air and over roll) techniques.

Maximum width: 50 cm; it can works in a speed range of 1 - 10 m/min;

drying-curing temperatures: 30 - 200ºC; pressure for padding (control of

the pick-up/uptake) can be applied in the range of 1 - 6 bar.

5

Auxiliary technologies: coating/padding

Knitted / weaved fabrics but also

nonwovens can be processed,

using some polymeric binders

(acrylics, PUs…) or some

functional finishing formulations

(liquid repellents, antimicrobial,

FRs, UV protectors…).




applications

Hotmelt lamination technologies are based in the use of adhesives that

are applied in a melted state (from 60 - 80 to 220ºC depending the

adhesive type) solidifying again quickly when are cooled down. Hotmelt

adhesives are dry compounds (solid content: 100%) and are applied

without the use of water or solvents. Pilot plant for trials:

Speed: 2 - 18 m/min.

Width: 250 mm.

*Different gravure rollers: 10, 15, 30 g/m2

Thermoplastic adhesives:

- polyolefins (PE, PP).

- etilen-vynil-acetate (EVA).

- copolyamides (PA).

- copolyesters (PES).

- thermoplastic polyurethanes (TPUs).

Reactive adhesives:

- reactive polyurethanes (PUR).

- reactive polyolefins (APAO).

6

Engraved* roller system available

FOR BONDING

DIFFERENT

MATERIALS

(including NWs)




applications

Auxiliary technologies: hotmelt lamination/bonding


applications

Plasma technology (dry process using only gas as raw material) is a

kind of surface treatment that activates polymeric materials (including

yarns, fabrics or membranes) increasing their reactivity. Plasma

treatments only modify the performance of the surface (not other

properties of the bulky material).

Activation of the textile surface (to improve wettability/adhesion

behavior) or possibilities to develop repellent nanocoatings on the

fabric surface (by plasmapolimerization) can be achieved. 2 pilot plants.

7

Surface treatments (by plasma technologies)

Low pressure plasma

Atmospheric (corona

discharge) plasma

To improve wettability:

Inorganic gasses (O2, N2)

To obtain repellency:

Organic monomers that

can polymerize

Power source:

100W to 1400W

Speed process:

5 to 50 m/min



Electrospinning is used for the production of nanofibers, starting from a

polymer solution. Method: high voltage is applied to a polymer solution

(some electroconductive performance). One electrode of the voltage

source is placed into the solution and the other is connected to the

collector of nanofibers (usually a NW). When charges within the solution

reached a critical amount, a fluid jet will erupt from the droplet at the tip of

the needle resulting in the formation of a Taylor cone. The electrospinning

jet will travel towards the region of lower potential, which in most cases, is

a grounded collector. A web of solid randomly oriented nanofibers is

deposited on the surface of the grounded collector. 4 pilot plants available.

8

Electrospinning technologies

Taylor cone

Nanofibers (NF) web

Randomly oriented

Collector (micro)

NF web (nano)




applications


9

Nonwovens (also for coating and laminating) is a growing worldwide

market.

The key processes to manufacture nonwovens are:

• Spunbond + meltblown.

• Needlepunch.

• Thermal or chemical bond.

• Spunlace / hydroentanglement.

• Air-laid.

• Wet-laid.



Taken from KELLIE SOLUTIONS. TCL 2012.

10

The melted filaments are swirled around and then deposited on the wire

mesh belt as a random nonwoven. This web is transferred to a bonding

calender that uses heat and pressure.

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- Quite high air permeability.

- Good mechanical & wear properties.

- Soft and comfortable.

- Average weight is 10 to 150 g/m2.

- Mainly for hygiene products.

- Protective apparel.

- Construction, agrotextiles…

- Battery separators.



applications

11

Mechanical bonding method: fibers are transported with felting needles

and interlocked in the nonwoven structure. This procedure increases

the friction between the fibers, which reinforces the nonwoven.

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- High speeds (> 150 m/min).

- It permits the use of recycled material.

- Fiber count ranging from 1 - 200 dtex.

- Average weight is 30 to 3.000 g/m2.

- Cleaning wipes, home textiles…

- Medical and hygiene products.

- Automotive, composites…

- Filters, geotextiles, protective apparel...



applications

12

The nonwoven web is consolidated in a thermal (hot calendering) or

chemical way (impregnation). Thermal bonding uses the thermoplastic

properties of certain synthetic fibres to form bonds under controlled

heating; chemical bonding is based on the application of a liquid

(bonding agent).

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- Mixture of natural / synthetic fibers.

- Different liquids for impregnation.

- Medium speeds for production.

- Industrial applications, composites…

- Automotive, acoustics, agriculture…

- Electrical insulation, coating/flocking…



applications

THERMAL

CHEMICAL

13

Spunlacing uses high-speed jets of water to strike a web to intermingle

the fibers. A vacuum within the roll removes used water from the product,

preventing flooding of the product. Spunlacing can be carried out using

natural or man-made fibers, or blends. Water recyclability of the system

should be high.

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- High-water-pressure machines are used.

- Softness and comfortable hand.

- Weight: 20-800g/m2; speed: 5-300 m/min

- Wipes, medical & surgical, cotton pads.

- Roofing felts and geotextiles.

- Apparel.



applications

14

Major advantage: very short fiber material can be applied. This is of

special interest for recycled fiber material such as cotton waste (e.g.

from spinning and yarn material). The fibers are fed into an air stream and

from there to a moving belt or perforated drum: they form a randomly

oriented web.

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- Air-laid webs have a low density.

- Greater softness.

- Absence of laminar structure.

- Automotive and transport applications.

- Composites, geotextiles, agriculture…

- Roofing felts.



applications

15

It’s a modified papermaking process. Main steps: 1) Swelling and

dispersion of the fiber in water and transport of the suspension on a

continuous traveling screen; 2) Continuous web formation on the screen

as a result of filtration; 3) Drying/bonding of the web. Water recyclability

of the system.

TECHNOLOGIES:

NONWOVEN

TECHNOLOGIES

SPUNBOND &

MELTBLOWN

NEEDLEPUNCH

THERMAL / CHEMICAL

BONDING

SPUNLACE

AIR-LAID

WET-LAID


- Innovative technology (5 - 10% of NWs).

- Usually 2 - 30 mm fibers are used.

- Bonding by hot calender or chemicals.

- Composites, reinforcement materials…

- Roofing felts, filters, insulating uses…

- Sanitary and hygiene applications.



applications


16

Nonwovens have a strong influence in the EU-28 textile industry. But

currently Asian countries are increasing their production force.


applications

Taken from KELLIE SOLUTIONS. TCL 2012.


17

The growth of non-wovens and of composites and their relation with

technical textiles.

In the past decade, the Technical Textiles sector has grown by 22%.

The technical textile sector is undergoing significant industrial change with

the growing importance of new applications (medical, sport and leisure,

aeronautics, environment), and a radical move from traditional

technologies (knitting, weaving, etc.) to more recent ones (like composites

or nonwoven-based technologies).

Growth in Europe is mainly driven by two technologies:

•Nonwoven with a growth rate of 60% over the past decade.

•Composites with a growth rate of 75% over the past decade.

And don’t forget the combination with high-tech finishing processes!




18

EU sector of technical textiles

obtained by finishing processes

(coating, laminating) is a highly

technical, very competitive market

and in a constant growth.

For example, in 2011, turnover of

laminating EU companies was

around 8.000M € (nearly 8% of these

companies in the EU were Spanish).

Demand distribution of coated / laminated

technical fabrics at European level, 2011 (Detrell

A. The European Coating and Laminating Sector.

TCL2012).




19

In Europe, hotmelt technology can

be currently considered as a mature

technology, which started to come

into use in the early 2000s, with the

development of new laminating

systems, new membranes and new

adhesives.

Nevertheless, it did take about 10

years to reach its true potential and

the leading technical finishing

companies have invested in new

laminating lines (or they are currently

incorporating it into their production

processes).

Sales evolution (data in M metres) of waterproof-

breathable textile articles in the EU (Detrell A. The

European Coating and Laminating Sector.

TCL2012).



applications


20

More technical properties, more added-value, more end-uses for your

nonwovens with finishing processes:



applications

PADDING KNIFE COATING DYEING PRINTING

EXTRUSION COATING METALLIZATION SPUTTERING

HOTMELT LAMINATION PLASMA TREATMENT THERMOBONDING


21

And the main global opportunities for new nonwoven-based applications

are:



applications

Growing needs of textile solutions from the end-users: comfort and

monitoring solutions for active life style, CO2 emission reduction in

transport (through reduced weight) and building (through thermal

insulation), improvement of medical technology (implants, health

monitoring), etc.

Close cooperation ‘producers + customers’ in order to address very

specific needs (tailor-made solutions) and demand-driven innovation.

Growing demand for recyclability and low weight (e.g. replacement of

foam by nonwovens, or replacing metallic parts by composite materials).

Quick growth of technical textile consumption per capita worldwide

and especially in China, India and Brazil. Emerging markets.


22 Infoday. April 22nd, 2015. Gaziantep (Turkey)


applications

Raw materials consumption. By applying the right forming and bonding

techniques, water consumption is drastically reduced. Also, modern

wetlaid or spunlaced production lines are recycling almost all of the

water consumed in a closed loop. Furthermore, thanks to ongoing

machine improvements, weights are possible down to 10 grams per square

meter, which means reduced fiber consumption.

Biodegradable fibers. Traditional disposables, like hygiene and medical

products, are in real trouble because of tighter environmental laws.

There soon will be no more landfills to handle used disposables. The

industry is challenged: PLA, cellulose-based (Tencel / Lyocell) fibers

and flushability performance (disintegration of towels or wet wipes when

are flushed down the toilet) required.


23

Opportunities in new products and applications for different sectors:

Geotextiles, agrotextiles and construction



applications


24


Geotextiles, agrotextiles and construction



applications


25


Filtration elements



applications


26


Automotive / transport



applications


27


Hygiene, and medical garments and wounds



applications


28


Supporting media / collector for nanofiber-based products



applications


29


Wet-laid technology for advanced nonwoven-based products



applications

Structural applications

when combined with a

conforming process!!!


30

CASE 1: FILTER FOR LUBRICANT OILS (FOR CUTTING

TOOLS)

Objective. Obtaining a needlepunched-based nonwoven for filtration of

lubricant oils, in order to enlarge life cycle of the filtering media and to

enhance possibilities for reusing the oils.

Clogging problems of the filtering media of complex liquids.



applications


31

CASE 1: FILTER FOR LUBRICANT OILS (FOR CUTTING

TOOLS)

Results. Multilayer material combining NW + woven PP substrate.



applications


32

CASE 2: NATURAL-BASED NW FOR SANITIZING GARMENTS

DURING THE WASHING PROCESS

Objective. Fabrics washed using a nonwoven impregnated with neem

extract.

A cellulosic nonwoven (NW) was impregnated -padding system- with

neem oil, and introduced on the washing machine with cotton fabrics. The

main goal was to transfer antimicrobial properties from the NW to the

fabrics.

Garments that are washed with detergents are clean and hygienized (of

course!!!) but they don’t show durable antibacterial properties (they are

not functional).



applications


33

CASE 2: NATURAL-BASED NW FOR SANITIZING GARMENTS

DURING THE WASHING PROCESS

Results. Functionalization of the nonwoven with a natural extract from

plants, and durable functional antibacterial properties on garments

washed with it.


applications


34 Infoday. April 21st, 2015. Denizli (Turkey)

New finishings for innovative

home and technical textiles

CASE 3: NATURAL-BASED ANTIBACTERIAL PROTECTION

FOR NON-WOVENS USED IN AGRICULTURE

Objective and results. Finishing of NW-based substrates used in

agriculture to protect vegetables/fruits from harmful bacteria-fungi. Use of

natural-based compounds for impregnating and finishing.


35 Infoday. April 21st, 2015. Denizli (Turkey)

New finishings for innovative

home and technical textiles

CASE 4: NON-WOVENS AS GROWING SUPPORT FOR SEEDS

Objective and results. Development of a non-woven based substrate

(with biodegradable properties) for supporting seeds during culture period

and growing of vegetables/fruits.


36

CASE 5: NON-WOVEN and NANOFIBER-BASED END-

PRODUCT FOR COSMETIC USE WITH HYDRATATION

PROPERTIES

Objective and results. Development of nanofiber-based webs (even

functionalized with active compounds) supported on a nonwoven, for skin

care and hydratation properties.


applications

5. CONCLUSIONS

37

New systems to develop nonwovens and special machinery with eco-

sustainable performance are available in the market.

New functionalities for develop non-woven based applications can be

obtained combining the NW substrate and a finishing technology.

End applications are in a wide range: from easy-to obtain and common

products (diapers, cleaning wipes, agriculture…) to high-technical end

uses (automotive, FR substrates, filtration systems, biomedicine-based

end applications, tissue engineering and cell culture…).

A wide range of end-products and markets can be reached with a right

combination of fiber + NW technology + functional finishing.



applications

Teşekkürler!!!

Thank you for your attention!!!

María Blanes ([email protected]). Team leader of the

R&D Group on Textile Finishing, Health and

Environment.

Oscar Calvo ([email protected]). Researcher.

R&D Group on Textile Finishing, Health and

Environment @ LinkedIn:

https://www.linkedin.com/groups/R-D-Group-on-Textile-

8102442/about

AITEX website: http://www.aitex.es

Technology

Nonwovens for technical applications