Edana Nonwovens Symposium: Rome June 4th-5th 2003

Key Points

• The development of 3-layer spun-laced nonwovens containing pulp promises to allow further wipes-substrate cost reduction by removing the need for the more expensive viscose fibres.
• As a step on the way to viscose elimination, the development of a 3-layer viscose/PP/viscose substrate with 75% PP offers cost reduction and better release of lotion.
• A 36 gsm 3-layer laminate of spunbond PP with a pulp core contained 20gsm of pulp.
• A semi-durably hydrophilic polyester staple also allows spunlaced wipes substrates with minimal viscose content.
• A breathable backsheet with comfort levels between microporous film and SMS is claimed to result from a 3-layer laminate of conulated film, melt blown and spunbond.
• “Extreme Modularity” in diaper machinery, said to be used by P&G and K-C, allows the production of training pants and diapers on the same line.
• A long-fibre card-less air-layer allows heavier weight nonwovens to be made with two layers. Powders and scrims can be easily added to allow, for instance, through-air powder bonded high-loft structures without use of bico fibres.

Introduction

Krzysztof D. Malowaniec (Paul Hartrmann - Germany) opens the meeting

Approximately 300 delegates, 12 from the USA, braved the heat, traffic and expense of a flaming Roman June to hear 18 diverse papers loosely linked by the themes of Strategy, Markets, Value, Environmental Benefits, New Materials and Machinery Development. As often happens with EDANA programs, the days are so full of speeches that the opportunities for networking and speaker cross-examination are limited. Nevertheless the audience appeared well satisfied with the event and looked forward to meeting again in Barcelona in June of next year.

World Market Update

Tom Van Gyseghem of Arthur D Little ( Belgium ) updated the 1999 survey of nonwovens in Europe presented at the EDANA Nonwovens Symposium in Prague . The current study was based on 35 interviews throughout the value chain and conversations with industry experts.

The key points:
• In 2006 world production will be 5.14 million tonnes; Western World growth will be 5% and the emerging countries 10-15%, giving an overall 7% CAGR.
• Most growth will be in the Middle East (CAGR 15%: Turkey , Israel and Saudi Arabia being the leaders) with Asia/Pacific at 11%, Rest of World 10%, and US/Europe at 5%.
• Recent growth in Asia has been entirely due to China : other major Asian nonwovens markets ( Korea , Japan , Taiwan ) declined.
• China continues to show the largest growth potential.
• Within Europe, Germany and Italy are the key producing countries; the former being strong in huge volume high speed lines while the latter favours smaller more flexible production.
• While wipes have grown at 25% between 1996 and 2001, this will reduce to 9% over the period from 2002 to 2006.
• Hygiene growth will similarly decline from 10% (1996-01) to 5% (2002-06) p.a.
• Overcapacity, a slowdown in innovation and a slowdown in industry consolidations characterise the current nonwoven roll-goods scene.
• Structural factors (commoditization, market saturation, consolidation failures, private label pressures) and cyclical factors (RM price increases, health care savings programs, slowdown in investment) combine to cause low profitability. European NW producers profitability is ~2%.
• Raw materials now account for 60% of total manufacturing cost.
• Half of world growth with be in spunlaid production.
• Worldwide market for web-forming and web-bonding equipment in 2002 was €700million: €450M in webforming, mainly spunlaid, and €250M in bonding, mainly needling.
• Most investment will be in China , Turkey , India , Korea , Taiwan .
• Chinese machine makers are beginning to break in to the Western equipment supply market.

In response to a question, Mr Van Gyseghem said that niche products were now providing the profitability for the roll goods producers, but large scale commodity production is needed to sustain the big-business approach to innovation. Learning to combine these extremes was a key to success. He recommended a book: “Innovation Premium” by a colleague at ADL.

China Market Update

Mr Wang Yanxi of CNTA ( China ) could not be present to give his paper, but the written version was available.
• Average annual growth of nonwovens production since 1978 was 23%
• 477,700 tonnes of nonwovens were produced in 2002 representing 0.36kg/capita.
• >90% of this feeds the domestic market.
• 71% were dry-laid and 29% were spunmelt
• Of the dry-laid, 145,000 tonnes were needled, 21,500 tonnes were spunlaced and 15,000 tonnes were airlaid.
• The spunlaced was produced on 18 lines, 7 of which used imported (western) machinery.
• The 128,000 tonnes of spunmelt is produced on 76 lines (65 PP, 10 PET and 1 SMS) Half of these lines were produced in China .
• Waddings (120,000 tonnes) remained the largest application.
• Hygiene/medical used 78,000 tonnes and Household/Wipes used 28,000 tonnes.

Nonwovens Declining

Teruo Yoshimura of the All Nippon Nonwovens Association ( Japan ) said Japan 's deflation had caused drastic restructuring of the nonwovens industry, which had declined by 5% in 2001 and 1% in 2002. Imports had increased by 70% since 1998 (30,000 to 51,000 tpa) but these changes were minor compared with the effects of deflation on the textile and fibre producers.

Over the same period, exports had also risen, from 24000 to 30000 tpa but the value of exports, 1461 Yen/kg was very much higher than the value of the imports (406 Yen/kg). 21% of these exports go to the USA and only 7% to Europe , so Mr Yoshimura felt that new emphasis on the European market was required. He drew some comfort from the fact that the decline was in commodity products, not in the high value specialities.

Of the 296,000 tonnes of nonwovens produced in Japan in 2002, 86,000 were needled, 83,000 were spunmelt, 42,000 were thermal bonded, 38,000 were latex bonded and 17,000 were spunlaced.

2003 had started well with Q1 nonwoven shipments up 2.6% over last year, but prices were still too low for comfort. Domestic demand (Production plus imports less exports) remained strong and did not show any decline over the deflationary period.

He felt the future lay in further developments of quality products made to Health, Environment, IT and Living themes:
• Biodegradable nonwovens
• Flushable and biodegradable diapers
• Stain-free materials using photo-catalysis
• Antimicrobials
• Industrial waste management nonwovens
• Chemical absorbing masks (esp formaldehyde)
• Anti-virus masks
• Anti-pollen masks
• Products for old age, e.g. Incontinence products, compresses for aches and pains.
• Fuel-cell separators
• PTT polymer for ultra soft nonwovens
• Aramid nonwovens for tyre reinforcement
• Precision Wipes (e.g. for LCD displays)
• Antistatic and electromagnetic shielding nonwovens

Hydrophilic Polyester for Wipes

Michael Witschas of Dupont-Sabanci Polyester ( Germany ) introduced their new Hydrofix® fibre which addresses the problem of finish wash-off in hydroentanglement. The fibre was “semi-durably” hydrophilic and the only clue he provided to how this had been achieved was to say what they had not done: i.e used plasma treatment, which was too slow and costly, or modified the polymer, which would make the fibre weaker. His definition of semi-durable was that the hydrophilicity would survive wet processing and several further wet extractions.

Comparisons of Hydrofix® with viscose in wet-wipe structures showed it to have:
• Better total absorbency and a sink time of 3 seconds compared with 1 for viscose and >600 for PES after hydroentanglement.
• In the nonwoven drop absorption test, the drop disappeared in 108 microseconds compared with 20 microseconds for viscose and 50 microseconds for the viscose/Hydrofix® blend.
• It has the same strength as regular polyester and gives HE fabrics 2-3 times as strong as viscose.

Asked publically about the cost, he could not say more than that it would be at a premium. Did they modify the polymer in any way? No: the process involved an aftertreatment to the fibre. In private conversation he said the price was likely to be nearer viscose than polyester. They had not used alkali hydrolysis to make the surface hydrophilic, neither had they grafted a surfactant to it. Wipes made from 100% of the fibre pass the lotion-drainage-in-storage test.

Better Lotion Release

Niina Salonoja of J W Suominen ( Finland ) described their development of a new wet-wipe substrate. The converters need strength with softness, wettability, absorbency and bulk and these properties were largely met with current market leading products. However, functionality, as perceived by the consumer, could be improved by providing better release of the liquid onto the surface. The standard 65% viscose/35% polyester substrate only needed absorbency for holding the lotion in place in the pack: in use it retained too much fluid. Increasing the synthetic content or moving to PP from PET both improved release, but compromised the in-pack performance.

The solution in all its elegant simplicity was to separate the viscose and synthetic into layers which will release the fluid more easily and hence allow the wipe to be made with less fluid addition in the first place. The 3-layer product, essentially a PP core with thin viscose skins, required three cards prior to HE.

Testing using a Dynamic Wiping Device provided proof of principle by showing that an 80/20 PP/viscose substrate released 75% of the simulated lotion (Triton X100) in 6 wipes compared with 56% for the 100% viscose. Further testing was carried out on a layered 70/30 PP/viscose blend in comparison with the 33/67 PET/Viscose standard. The layered product had a total free absorbency of 10.5 g/g compared with 8.5 g/g for an intimate blend of the same fibre composition, and 10.0g/g for the PET/Viscose control. Lotion release improved to 80% compared with 67% for the control.

Porosimetry measurements showed that the layered structure collapses more completely under pressure and hence retains less fluid. Clearly the main unspoken attraction of this approach will be the saving in costs for the nonwoven producer who needs to buy less viscose, and the converter who needs to use less lotion. Privately she confirmed they had tested the new fabric to prove it had sufficient vertical wicking to allow the top layer of a wipes pack to stay wet in prolonged storage

New Spunlace Structures

Mr Münstermann of Fliessner Maschinenfabrik ( Germany ) provided an update of developments on their Aquajet™ system. The newer claims were:
• Their twin-belt wet-out system with through-belt HE allows 10gsm webs to be processed on the line as a whole
• 300m/min was the top line speed quoted, 200m/min being the top speed for aperturing.
• 7m wide lines can now be made.
• They have an exclusive licence for 3-layer production with pulp filling whether tissue or air-lay. (From Georgia Pacific).
• Structuring or embossing the webs increases their bulk by 50-100%.
• Spunbond-fluff-spunbond structures allow 75% pulp to be used. (Collaboration with Reifenhauser)
• A 60 gsm SFS embossed wipe fabric is 1.2mm thick and costs €0.925/kg cf €1.52/kg for 60gsm viscose/PET with a 0.6mm thickness. Without embossing the SFS structure would cost €0.762/kg. (All costs for raw materials only)
• For 200gsm and above they can now process direct from a tuft-feeder, avoiding the cost of cards. (Collaboration with Trutzschler).

In response to questions, Mr Münstermann said embossing does not affect strength but increases fabric elongation. The lightest 3-layer staple product is currently 40gsm (10/20/10 PES/pulp/PES). 8gsm spunbond could also be used on the outside to reduce the weight further.

Better Breathable Backsheet

Dr Antonietta Splendiani of Tredegar Film Products ( Italy ) identified a gap in the breathable fabrics market. SMMS products provide excellent breathability but poor barrier performance while microporous films provide excellent barrier performance and poor comfort.

To fill the gap Tredegar has created a laminate of conulated film, melt-blown nonwoven and a spunbond, where the perforated cones of the film are upside down creating a raised surface to the composite. The spunbond only contributes abrasion resistance to the other outer surface. When a conulated film with a hydrostatic head of 32mm is laminated to a meltblown with a hydrohead of 305mm the composite had a hydrohead of 686mm. Dr Splendiani thought this was useful synergy rather than evidence that lamination reduced the permeability of the apertured film.

With regard to breathability the new laminate tested at 21,000 g/m 2 /day compared with 40,000 for SMMS and 5000 for a microporous film with a hydrohead of 877mms. Wearer trials showed that the humidity inside the new laminate rose more slowly, to lower peak levels and decayed more rapidly (when exercise ceased) than in the commercial “breathable” control. Tredegar will also develop a version for diaper backsheet use.

Disposables Production Revolution?

Thilo König of GDM ( Italy ) described how their latest “extreme modularity” approach to diaper making would allow the manufacture of training pants and diapers on the same line simply by switching 3 modules. Slides illustrating both the P&G and KC use of the principle with the BT 600 TP system were shown.

The various modules making up the line were independent and were built and tested as stand-alone units, to be assembled on site in whatever way the customer required.

Softness and Touch

Catherine Renault-Hartmann of BBA Nonwovens Corovin ( Germany ) noted that our overall impression of softness is made up of 5 key elements:
• Surface structure
• Stiffness
• Volume or bulk
• “Climate” – does it feel dry, wet, warm, cold, squeaky, slippery)
• Appearance

Every market needs a different combination of these elements. For instance diaper topsheet softness judgement relies mainly on surface structure and appearance and improving other softness elements could be wasting money. For surgeons gowns the key elements were stiffness, surface structure and appearance. Regional differences in the perception of softness exist also, Asian needs differing greatly from US needs.

The Value of Binders

Dr Holger Poths of Air Products Polymers ( Germany ) provided an overview of latex-bonding en-route to showing how their new Airflex EP1188 emulsion could improve resistance to moisture without spoiling the moisture vapour transmission rate.

EP1188 is a vinyl acetate ethylene copolymer with FDA approval, ultra-low (<5ppm) formaldehyde, and free of alkyl phenol ethoxylates. When 15-20 gsm is added to SMS or air-laid pulp nonwovens a contact angle of 91-93 degrees is obtained along with a hydrostatic head of up to 180mms. This is achieved without any lowering of the Moisture Vapour Transmission Rate.

In response to a question, he could not provide a copolymer spin-finish to make viscose hydrophobic.

Long-Fibre (and powder) Air-Lay

Akiva Pinto of Bettarini and Sefarini SRL ( Italy ) introduced a new long-fibre air-lay system that produced heavy felts directly from what looked like a traditional chute feed to a card. The Bemaformer® works with two fibre feed streams to give a two sided product and can also incorporate powders and scrims. The result could be a 100% PET high-loft nonwoven with a 10 kilo/m 3 density or could be compressed into denser structures.

The two fibre feeds to the Bemaformer® are provided by two Bemablow® units which in turn can be fed from Bemamixers® which improve the fibre blend or incorporate powders and chemicals (e.g for fire retardant). Bemaopener® units process the fibre feed to the mixers.

The system can process wool, glass, bico, kenaf, card waste, foam chips with shoddy, and ground-up carpet waste. Woodpulp was also possible! Throughput could be 1 tonne per hour but whether this was per meter width on the 2.5 meter wide line was not clear.

Absorbing Spillages

Robert Van Langeveld of New Pig ( Holland ) reviewed the evolution of oil absorbents from an outlet for waste melt-blown fabrics to the specifically designed systems for:
• Removing oil spillages from sea water, in harbours as well as in major incidents.
• Removing hydrocarbons from drinking water in water treatment plants
• Containing oil leakage from machinery, especially in the metal-working industry
• Cleaning up emergency spillages of oil and fuel in road accidents.

The key product development which “changed the paradigm” was the absorbent sock, a tube of spunbond which could be filled with a variety of cost-effective absorbents according to the problem and local conditions. Waste nonwovens, melt-blowns, vermiculite, straw had all been used.

The key market development was the MRO (Machine Run-Off Oil) which allowed the products to be used to prevent spillages and to keep the working environment in workshops safer and cleaner. The metal-working and chemical industries had become the leading users of these products. Rolls, pads and the more sophisticated disposable mats weighed from 175 to 400 gsm and sold for €8 to €14/kg.

Perhaps unsurprisingly with such a good mark-up on the PP granule price, the industry was now beginning to suffer from what Mr Van Langeveld called a cowboy element. It needed industry standards covering the strength and capacity of the products. Edana had taken the first step of establishing a sub-committee to look at test methods. Commoditisation was also becoming an issue. Incineration is the preferred disposal route, New Pig products being practically ash-free.

Nonwovens for absorbing spillages

Mr Büchsel of Schoeller and Hoesch (France) continued the oil absorbent theme from the standpoint of a fabric producer, pointing out that cleaning up major spills needs a high capacity product with fast uptake that can be delivered to the scene of the spill quickly. Melt-blown PP could be formed into booms, pillows, sheets, rolls and sweeps to replace the fluff, waste, cotton, sawdust, clay, and calcined diatomaceous earth now used. The products needed to have maximum capacity for rapid accidental spillage clean-up and here low strength was acceptable. However for preventative use, higher strength products with high abrasion resistance (spun bond skins) were needed and here the absorbent capacity could be lower. Contaminated products were covered by the hazardous waste directive and needed separate collection and storage in special containers. To absorb and dispose of 1 tonne of oil using the melt-blown products would cost €624 compared with €1200 for the cheaper powders. Furthermore 1 tonne of oil could be absorbed by 40kgs of MB and leave 20gms ash after incineration, cf 1 tonne of ash if diatomaeceous earth was the absorbent.

The main producers of the systems for oil clean-up were 3M, New Pig, and SPC in the USA and these all export to Europe . Ecotextil (Cz) and S&H (Fr) were the European producers. The system approach was however being spoiled by dumping of excess melt-blown capacity into this market.

Clay-filled Landfill Liners

Dr Han-Yong Jeon of Chonman National University ( Korea ) described the development of a clay-filled polyester for use in landfills. Here there is a problem of toxic inorganic compounds in the leachate and the clay helps the polyester to absorb these toxins. In the study presented, 12 denier staple fibre containing 2-3% of clay had been needled into fabrics from 272 to 1500 gsm and compared with similar products without the clay. The clay product had about twice the toxin absorption efficiency as the regular polyester. At one extreme the clay had no effect on iron absorption, and at the other it removed ~95% of the cadmium and lead compared with ~37% for the unfilled polyester.

Why limit the filler to 3%? Because the strength specification for landfill liners cannot be met with higher concentrations. Dr Jeon explained that in use the leachate can reach 80 0 C and has a pH above 8 so that a polyester needlefelt loses half its original strength. There was no consideration of how long the liner might remain effective.

Nonwovens in Furniture

Max Castellani of ATEX ( Italy ) enumerated the requirements the furniture construction industry placed on spunbonds:
• Good barrier to liquids and dust-mites
• Antimicrobial
• Low flam
• Good aesthetics
• Available in a wide range of colours to match the face fabrics.
• Good light fastness
• Breathable
• Sewable/heat sealable

The furniture industry also needed nonwovens for use in the finishing process:
• Polishing wipes
• Anti-scratch surface protectors
• Transit Blankets

Wipes had to be very soft microfibre materials to avoid scratching. Dry wipes were needed for dusting, wet-wipes which can release the lotion and reabsorb it were needed for polishing

Improving Barrier Performance

Clemens Tuente of Cognis ( Germany ) described work aimed at improving the alcohol, oil and static properties of SMS without spoiling the hydrostatic head. Cognis targeted an improvement in alcohol repellency ranking from 2 to 10, in oil repellency from 0 to 7 and a reduction in electrical resistance from 10 13 to 10 11 ohms by using combinations of their fluorocarbons, extenders and antistats.

Unfortunately the drying/curing temperatures required for the fluorocarbon were close to the melting point of PP, and the heat treatment spoiled the water barrier performance (hydrostatic head test, HH). Furthermore the HH was also adversely affected by the antistats used.

Mr Tuente concluded that with a low melting fibre like PP, it was impossible to meet all the goals simultaneously. However their Repellent NFC/KFC would allow higher alcohol hold-out (>5) without compromising the other properties.

Dr Schacher of the Ecole Nationale Superieure des Industries Textile de Mulhouse ( France ) compared disposables and reusables in hospitals in France and Portugal . The EU-funded study carried out between March and September 2001 contacted 169 French and 83 Portuguese hospitals and was compared with a 1996 survey of 89 Portuguese hospitals. Only 32 of the French hospitals responded. None of the data appeared convincing and the only conclusion of note was that private hospitals used more disposables than public hospitals, a trend that had increased since 1996.

Innovation Focus

Rich Chapas, Consultant (USA) reviewed the route to the successful introduction of new products from a nonwoven industry viewpoint. He listed:
• Set Strategy and Goals
• Define the Innovation Leadership Team
• Analyse the portfolio of possible projects
• Define the opportunity
• Appoint the project champion
• Use tools such as market research, focus groups, trend analysis.

Cotton Surfaced Nonwovens

Dr Larry Wadsworth of TANDEC (USA) recycled his paper on cotton/PP laminates made by calendering the webs together in various combinations. The work was supported by Cotton Inc. and Eastman. If the PP was replaced by Eastar Bio or PLA a biodegradable laminate could be obtained. Unfortunately Eastar Bio proved uncardable due to its elasticity, and the PLA as received proved unwettable. A bico fibre with a PLA core and Eastar Bio sheath gave better laminates with cotton. Sonic bonding gave better bulk than calendering, but less strength. Wetting agents gave faster wetting.

C R Woodings 11/6/2003