- The big new HE line going into East Germany has Trutzschler opening, Thibeau cards, Danweb air-lay, Fleissner HE and dryer and Celli winding. It will make wet-wipe fabric at 250 m/min and 50 gsm from polyester and pulp. It is 5 metres wide and Fleissner plan to show the actual HE zone at Achema in Frankfurt at the end of May. The 20,000 tpy output is rumoured to be mainly for P&G.
- BBA’s new air-laid line in China may reduce Oji’s ability to sell air-laid in China, not just because of competition but because the tariff on air-laid imports might increase. Oji remain confident that their quality will be superior.
- The new HE line in PGI Cuijk is relatively narrow (1.85 metres) but fast. It uses Perfojet technology but is also “Miratec” capable should the need for additional production be needed.
- The Nan Lui Spunlace line due to start on June 10th is a 3.5 metre wide, 350 tonnes/month line with Trutzschler openers, Thibeau cards, Perfojet HE, Fleissner Dryer and Celli Winder.
- The Taiwan Spun-Lace Group is run by 3 former Hon-Yen employees who, according to Hon Yen, used their patented designs. Hon Yen are now invoking their patent.
- Kanebo were showing their Lactron PLA fibre as carrier bags, shoe cleaners and a knitted golf-shirt. The shirt felt rather like knitted viscose: too limp and “heavy” to be really attractive.
- Shinwa were showing the AQF active carbon fabrics, and their Shintex division was showing lightweight PLA spunbonds under the “Haibon” name. It appeared to be available as kitchen sink drainer bags, gift-wrap, bin-liners and disposable diapers. They also had a film/spunbond laminate. Numerous agricultural fabrics were illustrated.
- The “Hottle” heated baby wet-wipe dispenser looked interesting. The wipes appeared to be perforated coreless rolls (200 wipes) that fitted in the cylindrical heater which had a list price of 10,900 yen.
- The PLA spunbond on NKK’s stand was a demonstration of the capability of their spunbond machinery to process the Cargill Dow resin. They do not sell the nonwoven.
- Cargill Dow only supply PLA resin to Unitika and Kanebo in Japan.
- MIRATEC fabrics from PGI are looking better than they did a year ago, but still appear to be in need of a major outlet. PGI seem to be getting disillusioned with textile replacement (ref. Rolf Altdorf’s comments recorded later), but are still showing shirts and jackets that impress nonwoven producers more than apparel makers. Like the similar stitchbonded materials, they should find most application in window and wall covering.
- Freudenberg’s EVOLON is made on a 1.6 metre wide HE line in weights of 90-300 gsm. Samples on show were typically PES/PA (65/35) bicomponents, HE’d and then thermally stabilised. They were very good as nonwovens and apparently better than MIRATEC but still appear too low in abrasion and too dimensionally unstable to compete with wovens in apparel. They plan a 3-3.5metre wide production line to come on stream in 2002. They will put together whatever nonwoven and textile technologies are needed to penetrate the textiles market more deeply. SMS, HE’d was said to be a possibility as was spunlaid, needled and HE’d. Apart from the slightly cheap-looking garments made from EVOLON, none yet commercial, the main outlets were sticking plasters, automotive nonwovens, shoe fabrics and surgical masks.
- BFF has been up for sale but offers have all been below asset value. Lamont, looking for cash for the last year, have since sold their Northern Ireland Carpets division so BFF is now likely to be divested as a management buy-in.
- Futamura’s output of TCF (spun-laid viscose) is still only 3500 tonnes/year
- FukuyoCo. Ltd (President Mitsugu Takahashi) have 50% of Japan’s private label wet-wipe market. They make 20 tonnes/day of spunlace, mainly rayon polyester. “Pigeon” is their brand, and they also make for Kao and Oji.
- Toyobo were still showing their LANSEAL cross-linked polyacrylate superabsorbent fibre made by hydrolysis of acrylic staple fibre.
- Toyobo’s MOIS CARE high-hygroscopicity ammonia-absorbing fibre – “4 times more hygroscopic than cotton”, moisture regain = 41% at 65% RH – appears to be based on partial hydrolysis of acrylic fibre. It also has a high heat of wetting and comparisons were being made with duck-down as an insulator. After the first absorbtion-desorbtion cycle, further wetting/drying appears hysteresis-free.
- Toyobo’s N-48 fibre is specifically targeting ammonia absorbtion. It picks up 100mls of ammonia per gram of fibre when in an atmosphere containing 50ppm of NH 3. With 2000 ppm NH 3 availability it only picks up 130 mls/gm fibre.
- Toyobo’s N-63 fibre targets gaseous aldehyde and acid absorbtion and they claim it has faster take-up than active carbon. When loaded, it can be returned to its orginal absorbtive state by heating and washing. It targets air conditioner filters, bedding and sanitary materials.
- Bioshield Technologies Inc. were showing their EPA registered AM 500 antimicrobial additive based on a silane quat.
Anex Conference Paper Summaries
ANNA’s View of the Future
Shozo Iwakuma, Chairman of Japan Vilene and of
ANNA , saw the continued development of durable nonwovens to replace woven
and knitted products as the main trend driving the industry’s future growth.
Artificial leather provided an
excellent example of the possibilities: the suede-like microfibre nonwovens now
being preferred to leather in many shoe, upholstery and garment applications.
However a consequence of their success was that most people did not know that
these products were nonwovens: the substitute image is invariably negative, so
producers and users alike keep the technological origins of the material quiet.
The same will be true when the next generation of nonwovens, exemplified by
Freudenberg’s EVOLON and PGI’s MIRATEC move into outerwear.
To succeed in apparel, the basic hydroentangled fabric
must develop a better softness/durability balance. Freudenberg have chosen to
achieve this by using spunlaid splittable bicomponent fibres, converted to
microfibres in high pressure hydroentanglement, patterned and finished to mimic
the appearance of woven and knitted fabrics. Extra density and strength would
still be needed, and could be achieved by using shrinkable fibres, or thermally
bondable fibres. However an extra mechanical bonding process such as needling
would probably give the best results. His comparison of the dry-lay
versus the spunlaid approach to these hydroentangled products was in
essence a comparison of MIRATEC versus EVOLON: the dry lay (MIRATEC) could
choose a wider range of fibre types and would tend to give more precise “weave”
patterns than spunlaid, but spunlaid would have higher productivity, lower costs
and better strength and durability. He saw the dry lay route as succeeding best
in upholstery and some outerwear, whereas the spunlaid approach would also
penetrate leisurewear and sportswear markets. He saw neither
approach being good enough for “designer” apparel.
His figures for 1998 Asian production of
nonwovens were Japan - 302,000 tonnes, China - 255,000 tonnes, Korea -
127,000 tonnes and Taiwan 124,000 tonnes. Asia has only 40% of the spunbond
capacity of Europe or the USA, probably because it’s coverstock market is about
half the size of those in the West. The dry-lay sector accounts for almost
three-quarters of the total tonnage, a statistic influenced by the preponderance
of weighty needlepunched materials in Asia. Interlinings account for 30% of
Chinese nonwoven production but only 4% of Japanese: a consequence of the
movement of the centres of garment production.
INDA’s View
Ted Wirtz, President of INDA said that Advocacy
and Education were the two main planks of INDA’s strategy and proceeded to
educate delegates in the latest data on the US nonwoven market.
Instead of the terms “Durable” and “Disposable”, INDA were now adopting
Long-life and Short-life to avoid the negative connotations of
the word disposable. Short-life nonwoven production amounted to 16,500 million
square yards in 1999, hygiene being the biggest sector with 64% of this but
growing only at 2% per year over the last five years. The liquid filtration
sector was showing 10% growth, (gas filtration – 6% growth), filters as a whole
being 8.5% of the total yardage. 3,490 million sq.yds of the heavier Long-life
fabrics were made, Upholstery (1,320 million sq. yds being the largest sector.
Growth rates of 5-6% were typical in this area.
Mr Wirtz pointed out that INDA planned to continue to
provide the low-cost statistical information that he felt was an essential
service to enable the industry to measure its progress and plan its future.
Details of how to buy the data was on the INDA web-site.
Patenting activity was always a good
indicator of future trends. Kimberly Clark, 3M, BBA, PGI, Johns Manville, and
P&G were, in that order, the leading patenters in 1999, but more revealing
was the fact that over half of the patents taken out related to Spun/melt
nonwovens. Wet-laid accounted for 12.3% and dry-laid only 7.7%. Other
interesting pointers to the future were the facts that 35% of world nonwovens
were now made by the polymer to fabric processes (as opposed to staple fibre to
fabric), and that total nonwovens growth in the developing world was running at
8-10% per year compared with only 3-5% in the developed markets. In future INDA,
in collaboration with the other associations, would be hoping to provide global
statistics on the same low-cost basis.
EDANA’s View
“Increasing the awareness of nonwovens” was, said Rolf Altdorf, Chairman of EDANA, the mission of the European association. Fewer but larger companies now produced nonwovens. Barriers to entry were increasing, a point illustrated by the fact that 5 years ago you could buy the latest dry-lay hydroentanglement line for $10M: now it would cost $30M. He also drew attention to the increasing segmentation and specialisation that was occurring. Hydroentanglement had been invented, and the first machines built, by Dupont and PGI-Chicopee, but to buy a machine you now went to specialist builders like Perfojet or Fleissner. Future growth required the nonwovens producers and machinery makers to develop new technologies, and innovative customers to broaden the range of applications.
Picking up on Mr Iwakuma’s mention of MIRATEC and EVOLON
targeting conventional textiles, he pointed out that MIRATEC is now regarded as
a new material in its own right, neither nonwoven nor textile, by the companies
converting it. PGI are no longer specifically targeting textile applications.
The View from Guangdong
China ’s Guangdong Province has its own nonwoven
association led by Mr Cui He. Mr He explained their aims as a) to promote the
development of the local nonwovens industry by “building bridges” between
government and the nonwoven producers, b) to open up domestic and export
markets, and c) to facilitate economic and technical exchanges with other
producers around the world. Guangdong, the mainland region adjacent to Hong Kong
and Macao accounts for 10% of China’s GDP but handles 40% of its foreign trade
thanks to massive foreign investment in the region. It is the leading exporter
of textiles, fibres and polyester polymer, the latter two categories amounting
to 300,000 tonnes/year. It has 215 nonwoven production lines making 167,000
tonnes of fabric, or 30% of China’s total production. Over half of this is
exported. Spunbond is the leading technology with around 50,000
tonnes annual output, and this includes a 3.2 metre wide SMS line making
products in the 10-150 gsm range for surgical masks, gowns, caps, for protective
clothing and home furnishings, all for export. 60,000 tonnes of dry-laid
spray-bonded nonwovens are made for “insulation” mainly for the domestic market.
This is distinguished from dry-lay latex bonded (10,000 tonnes), mainly for
interlinings, but wall-paper, embroidery cloth and packaging cloths being
mentioned. Dry-lay needling (up to 4.2metres wide) accounts for 30,000 tonnes of
the total, going mainly into domestic carpets, felts, coating bases, geotextiles
and filters. Thermal bonding, at a maximum width of 2.5 metres appears to be
“old technology” and makes 15-150 gsm fabrics, the lighter products mainly for
domestic hygiene products. 3000 tonnes of the thermal fabrics are made by
through-air bonding.
Mr He expects total Guangdong nonwoven output to reach
300,000 tonnes by 2010, and sees the way forward as investment in fast polyester
spunbond machinery, high pressure hydroentanglement machines, and big, fast,
needlelooms.
The Dupont Forecast
James Young, a research fellow in material science and
engineering at Dupont’s Central R&D described their “3 Horizon” view of the
future of nonwovens.
- Horizon 1 (up to 2 years ahead) would see “combinations of flexible sheet technologies for new functionality” e.g. growing usage of laminates of nonwovens with microcellular foams, microporous films, and further advances in SMS and PET/Pulp hydroentangled products.
- Horizon 2 (up to 8 years ahead) would see increasing dominance of spunbond and meltblown nonwovens including moves into advanced polymers for higher value high-tech applications. (“Hylar” mentioned)
- Horizon 3 (10+ years ahead) would see a move from oil-based to nature-based polymers, made initially by fermentation and later within genetically modified plants. (Dupont is working on a nature-based polyester: genetic modification of soya was mentioned).
By 2010 he expected global production of nonwovens to
reach 5 million tonnes with a dollar value of $15 billion. Polymer-lay processes
would continue to gain over fibre-lay and reach 47% of the total ten-years from
now (c.f. 8% in 1980 and 35% in 1990)
Applications development emphasis would
change from disposables to durables, commodities to specialities, niches to high
technology engineered products (HTEP) and from two-dimensional products to
three-dimensional products. By HTEP he meant better geotextiles, advanced
battery separators, microelectronics packaging, printed circuit substrates,
biomedical separators/filters and security “papers”(i.e. polymer-based papers
for currency and cheques with anti-forgery elements built in).
More specifically, Dupont were now working on new
spunbond processes that would dramatically improve the evenness and hence the
value of the nonwoven (or paper?) product. He would not be drawn further, but
the new technology would not be compatible with existing turn-key spunbond
operations and appears likely to regain Dupont a leading position in spunbond
manufacturing and maybe later, machine supply. They are likely to publish more
in the next 1-2 years.
Hainan Xinlong Expansion
The paper from Mr Guo Kaizhu, President of Hainan
Xinlong Nonwovens described the companies success since completing the first
phase of construction of their hydroentanglement plant 4 years ago. Six
Departments of State had evaluated HX as “a national large-scale and first grade
enterprise” and the Department of Technology rated it a “key national advanced
and new technology enterprise”. ISO 9001 and IQNET certificates were awarded 2
years after start-up, and the company is now recognised as the leading Chinese
nonwoven company both domestically and internationally. However because in the
last year all large Chinese companies have suffered more intense competition in
the market, HX has decided to add a new lightweight PET spunbond line, a third
speciality hydroentanglement line, and a microfibre synthetic leather line. The
new lines will allow them to make new protective nonwovens with attributes such
as breathability, flame retardancy, and high tensile strength; insulation
fabrics for electrical and optical cables, and a new type of agricultural crop
cover. Within 3-5 years HX intends to create China’s largest nonwoven operation
incorporating a National Nonwovens Industry Technology centre.
Hi-Loft carriers for Active Carbon or SAP
Gunter Groeger of AQF Technologies LLC described a new
nonwoven with active carbon particles bonded into the structure in such a way
that they were firmly held with minimal loss of available surface area. The
patented process was not described, but the illustrations suggested through-air
bonding of a bicomponent fibre structure with excellent distribution of
particles underneath surface skins that were denser than the body of the fabric
and free of particles. Particles were ideally 300-600 micron diameter, particle
loadings of 75 to 750 gsm were mentioned, and total thickness varied from 1mm to
3mm over this range. The sheath of the bicomponent fibres flowed into the the
particles on melting, “spot-welding” them to the 15 micron fibres. The target
application appeared to be automotive cabin-air filters (removal of exhaust
volatiles), but removal of gaseous contaminants from clean-rooms, archives,
offices (tobacco smoke), kitchens, homes (outgassing of building materials) were
also mentioned. Of interest to the disposables industry were claims that if
superabsorbent granules were used, the controlled spacing and immobilisation of
the particles prevented gel-blocking problems. Ion exchange beads can also be
used.
Asahi’s Lint-free “Cotton” Wipes
Mr Yoshiji Kaneko of Asahi Chemical Industry Co. Ltd.
reviewed the Industrial Wiper market as a whole and then focussed on the
requirements of the microchip industry, whose wiping requirements were now
largely met by woven and knitted synthetic continuous filament yarn products.
This was a tough sector for nonwovens to succeed in, but the rewards could be
high. The ideal nonwoven would of course have to be lint free to the very high
standards required, would have to absorb distilled water and organic solvents
such as alcohol without losing any ionic materials into the fluid, and wipe
without streaking. A binderless spunlaid cellulosic nonwoven such as Asahi’s
“Bemcot” seemed to be ideally suited to take on the current market leaders.
Because this spun-laid cupro rayon process dissolves
cotton linters rather than woodpulp, Asahi have always described their products
as cotton wipes or swabs. They were now also claiming an “ECO”
classification due to the fact that linters were in fact a recycled product,
being recovered from cotton seeds after the fibre has been removed. Production
of the spunlaid cellulose nonwoven, in which fibres are spun, washed and dried
on a single long conveyor belt, is 4000 tonnes per year, 35% of this output
going into industrial wipes. Maximum available fabric width is 1750mm. Filaments
are typically 1.3 dtex and high pressure water jets are used to wash and
aperture the nonwoven. “Bemcot” is a true spunbond; the fibres being sticky when
laid so a self-bonded product with very low lint levels can be obtained.
Lint Testing
Asahi used 4 types of linting test to characterise
clean-room wipes:
- To estimate particles likely to be shed in the wet state they stirred the nonwoven in 300 mls of pure water for 15 minutes, removed the wipe and filtered the water through a black Millipore filter. Microscopic particle counting, or in bad cases, measuring the whiteness of the black filter quantified the lint. Here “Bemcot” wipes clearly outperform hydroentangled rayon or polyester/rayon, with PET/pulp being worst.
- For particles likely to be shed in the dry state, what appeared to be a Gelboflex tester and Coulter particle counter were used. This test however gives artificially good results due to the difficulties of shaking small, often electrostatically charged particles out of the fabric in the flexing process.
- The use of a particle counter after the wet agitation method described in 1 was now thought to give a better estimate of dry-state shedding than method 2.
- The wipe, wet or dry, is attached to a weighted sledge and dragged across a mirror in a standardised way. High-intensity angled illumination allowed any particles left on the mirror to be seen and counted easily.
The Japanese wiping market as a whole (including paper
towels and textile wipes) was worth 250 billion yen. This was broken down into:
- 65 billion Yen of “Industrial”, defined as clean-room, electronic industry, printing industry (all speciality products) and general purpose industrial wipes.
- 85 billion Yen “Commercial”, defined as medical, oshibori, food service and paper towels .
- 100 billion Yen of “Domestic”, defined as baby wipes, other wet-wipes, glass cleaners, car cleaners, floor wipes and kitchen wipes.
Nonwovens amounted to 40% of this value, or 10% in
tonnage (40,000 tonnes per year). The premium priced sector – cleanroom wipes,
would follow the microchip industries growth (15% per year) but would also
follow its relocation from Japan into East Asia.
New Uses for PET Spunbonds
Dr T H Ahn of Kolon Industries Inc., Korea’s biggest
polyester spunbond producer, has widened the range of possibilities for
polyester spunbonds by several techniques including applying different finishes
and coatings. He mentioned a wide range of applications, some old some new,
without always indicating how they had been achieved or what they were
targeting:
- battery separator for mobile phones
- optic cable wrap (absorbent coated)
- antistatic materials
- ink-jet printable “paper” for high quality display media
- industrial filters including a “dioxin capture” filter
- sound absorbents and opto-catalyst nonwovens
- backing sheets for underfloor heating elements
- chitosan coated spunbond for wound dressings
- capilliary matting using Y-shaped fibres
- Y-shaped fibre spunbond for high lustre
- “micro-crater” fibre spunbond apparently made by adding silica gel to the polymer to get a porous surface.
- Ultra-micro fibre spunbonds
- New polymers: polyethylene 2,6 naphthalate – PEN - for UV resistance, polytrimethylene terephthalate - PTT - for elasticity, and polylactic acid - PLA - for biodegradability.
- On line laminates: they had facilities to add powders or scrims between the two spunbond heads.
The inkjet printable banner paper was made 60 inches
wide by on-line spray and/or knife-over-roll application of a printable surface.
After coating an IR drier fixed the coat before through-air bonding.
11,000 tonnes of Korean PET spunbond production was
split 40% geotextiles, 22% civil engineering, 15% industrial, 7% filters, 5%
cable wrap, 5% packaging and 5% unidentified. This would grow to 18,000 tonnes
by 2002, mainly due to the ink-jet media taking-off.
New Cotton Disposables?
Mr Mac McLean of Cotton Incorporated listed the next
generation of cotton disposables as:
- Wet-wipes based on the nit-free air-laid and wet-laid products now possible
- Ultra-thin pads
- Training pants with cotton core
- Air-laid absorbent core composites (for preemie diapers)
- Cotton/PP coverstocks (for preemie diapers)
- “Purely cotton” facial tissues for sensitive skin
- Panty liner based on Buckeye air-laid cotton.
SMAS
Dr Alvin Hu of the Kang Na Hsiung Enterprise Co. Ltd,
Taiwan described experiments with 4-layer composites: spunbond, meltbown,
airlaid pulp, spunbond (SMAS) prepared in their pilot plant by off-line
lamination (calendering) of a SM laminate to an AS laminate. The laminates were
tested for strength, hydrostatic head, rewet, wicking, air-permeability and
moisture permeability, the main variable being the meltblown layer.
Despite the 4-layer title, most results were on the SM
layers alone and unsurprisingly showed that:
- When 0-30 gsm of MB was added to a 10 gsm SB, the hydrostatic head increased linearly from 0 to 60cms.
- Dropping the MB fibre diameter from 3 to 2 microns raised the head from 30 to 70 cms.
- Air permeability decreased from 13,000 l/sq.m/sec to 7000 as MB weight increased from 15-30 gsm
In the 4-layer structure, raising the weight of MB from
15 to 30gsm had no effect on horizontal wicking and the rewet data allowed no
sensible conclusion to be drawn.
Cell Culture on PP Spunbond
The Biomedical Engineering Centre of Taiwan’s Industrial
Technology Research Institute has, in conjunction with Union Chemical
Laboratories, developed a nonwoven to which animal cells can adhere during
tissue culture. Mr Lien Chen of UCL said that BEC’s bioreactor was designed to
use a PET nonwoven, but appears to work better with a modified PP nonwoven. The
best results (almost double the cell-growth rate compared with the polyester
control) were obtained when PP was first activated with helium, treated with
allyl alcohol and PEG 3500, and sterilised. The use of plasma to polymerise HEMA
onto the PP surface had a similar effect at about 10% of grafted HEMA, higher
and lower levels being less effective. Mr Lien stressed that the results were
preliminary.
Latin American Markets
Rolando Dominguez, Marketing Director of PGI Latin
America reviewed opportunities for disposables in the Latin American Market,
defined as the 454 million people living south of the USA. 1996 data showed
diapers had only penetrated 16% of the market, feminine pads 24% and adult
incontinence products 1%. Chile, Argentina, Venezuela and Mexico used the most
disposables, and Mr Dominguez felt that Brazil, Columbia and Mexico provided the
best opportunities for inward investment, with adult incontinence being the most
attractive sector. He felt that any investment should target several countries,
should obtain the available grants, should take advantage of free trade
agreements, and should link up with a local company for sales and distribution.
Battery Separators: A Growth Market
The growth in mobile communications and computing has
created a large and rapidly growing market for high performance rechargeable
batteries that depend for their performance on high quality battery separators.
Now the introduction of electric and /or hybrid vehicles by Nissan, Honda and
Toyota looks set to drive this once niche market into the mainstream of hi-tech
specialities. Tetsuo Sakai of the Osaka National Research Institute reviewed the
scene, indicating that the growth may go to products other than nonwovens.
Nickel metal hydride (NiMH) and Lithium-ion (Li-ion) batteries were the fastest
growing with 80% of the portable appliance market and increasing use in cars.
Honda were using NiMH for their new hybrid car and Nissan had adopted Li-ion.
For portable devices, small size was obviously crucial and with some 20% of
battery volume being separator, thinner, stronger more uniform separators were
needed. Membranes were being used, their thickness being reduced from
150 to 120 microns to make AA size Lithium Metal Hydride (LiMH) batteries
possible.
Dry-lay technology once dominated the sector and
although wet-lay was now predominant it had strength shortcomings. These were
solvable by moving to bicomponents which could be split in hydroentanglement,
the resulting nonwovens being calender bonded to strengthen and densify them.
The move to microfibres was crucial to get good barrier performance in
thin products and relatively unusual fibres such as PE/EVA bicomponents
performed well. Fibre surfaces had to be modified by adding an ion-exchange
group to allow them to hold onto electrolyte under high pressure. For lithium
batteries a multilayer microporous film separator was proving best
because this construction gave the necessary “shut-down effect” in the event of
accidental shorting. Lithium Polymer and Solid Polymer Lithium batteries are
under development, the former using a gel polymer separator, the latter using a
“solid polymer electrolyte film”.
Ultra-high modulus laminates
Professor Chang Whan Joo of the Department of Textile
Engineering at Chungnam National University, Daejon, South Korea described how
high strength high modulus felt conveyor belts were made. Strengths in excess of
180 kgs/sq.cm with extensions below 3% were achievable but only in composite
products where the needlefelts were laminated on either side of a scrim by
further needling prior to thermal stabilisation. He took as an example a 5000
gsm, 7mm thick belting made from a blend of 20 denier 88mm polyester (60%) with
40% of 4 denier 51mm “low melting point” fibre. These fibres were formed into a
150gsm pre-needled felt with a thickness of 6mm. A 4-ply laminate of this was
then made, also by needling, and the final belt was assembled, by taking two
layers of the 4-ply laminate and needling them either side of 4 layers of woven
scrim made from multi-ply continous filament Kevlar weft yarns across a
continuous filament polyester warp. The resulting 12-layer laminate was
stabilised by heating at 150 C for 3.5 hours. Such “nonwovens” were used in
compressive shrink finishing, transfer printing, calendering, ironing, and
embossing processes. The work had been funded in part by the Bo Woo Co. of Korea
who also make lighter weight versions for use in shoe construction.
Wool for Noise Control
Wool, being relatively low density (1.33), highly flame
retardant and having surface scales that absorb sound, is well suited for use in
noise control if it can be delivered in the right form. V.B. Thakare and A.K.
Rakshit of ADRDE (India) have now taken 21 micron, 10mm comber waste wool
blended it with 3 denier 75mm polypropylene and produced a range of needlefelt
blends. The best balance of Noise Absorbtion Coefficient (NAC) and strength was
achieved at around 70% wool for a 300gsm felt, 4.4mm thick, needled to 200
punches/square cm. As expected multiple layers of felt were more effective than
a single thick layer, due to the increase in entrapped air. The same effect
allowed good performance when a jute cloth (1.1mm thick, 12x12 tpi plain weave)
was placed between two layers of the needlefelt.
Footnotes to Anex:
- Of the 17 papers in the programme, 7 appeared in the book of papers and 2 of these were in Japanese only.
- An additional 6 were distributed on the opening day.
- Several speakers who sent their papers in on time found they were neither in the book nor available as copies.
- While the exhibition seemed well attended there were fewer exhibitors than ENA 97, and very few stands had set out to provide adequate information in English.
- The original vision of an annual major conference and exhibition, the venue rotating through Europe (Index) USA (IDEA) and Asia (Anex) has not materialised: Anex is still just one of several Asian meetings, all much smaller than either IDEA or INDEX.
- There seem to be too many Asian nonwovens associations and too many conferences.
- Whether the planned creation of an Asian Nonwovens Association can correct this remains to be seen.
Points from the CINTE Conference and Exhibition
This was, to use the new terminology introduced by Ted
Wirtz at Anex, a conference biased towards long-life nonwovens. However the
presence of Acordis Industrial Fibres, Lenzing and Alceru Schwarza provided some
useful insights into the current state of the lyocell business. This is dealt
with first.
Lyocell Developments
- Lurgi-Zimmer held a lyocell seminar in China in early May attracting 60-70 interested companies.
- Alceru Schwarza’s collaboration with Lurgi- Zimmer has not yet resulted in an order for a lyocell plant, but there are three Chinese lyocell R&D projects all competing for government funding to build the first large pilot plant in China.
- AS believe there is no more work to do on the conventional staple approach, and seem unsure about the next steps on filament. They believe Acordis might do a JV with filament lyocell in South America. (JV in China is more likely according to Acordis)
- AS have had a “really hard time” getting around the patent suites of Acordis/Lenzing (now pooled). They are now 99% sure that they are in the clear. They say there is absolutely no truth in the Acordis/Lenzing statements that if AS are in the clear, they must have an uneconomic process.
- The US deal being discussed between Lenzing and Acordis could now involve lyocell as well. AS believe that Lenzing could take control of the viscose operations of the two companies leaving Acordis with lyocell. This is not confirmed by Acordis or Lenzing.
- The Alceru pilot line is rated at 500 tonnes per year, but now operates at only 300 tonnes. It uses belt washing of staple. Having recruited several people from Heiligenkreuz, Lurgi-Zimmer are pretty familiar with the Lenzing technology. They do however feel Acordis’s ability to mechanically crimp a tow is superior to the washbed “deformation” approach used by Lenzing.
- Acordis now have the second MobileTencel line restarted and plan to reopen the third in September. The market, especially in Asia is very strong, and they are even talking debottlenecking to increase their capacity – nominally 85,000 tonnes but Grimsby is not yet up to nameplate capacity. Non-apparel sales are still below 4000 tonnes/year. (The improving apparel market has once again allowed them to increase prices to reduce their aspirations in the nonwovens and technical products field.)
- Viscose is in short supply and prices are increasing. (Spun-lace producers are finding that the shortage is preventing them expanding the baby-wipe market at the rate the market would stand.)
- Lenzing are slowly getting up to (lyocell) capacity at Heiligenkreuz, and claim some unspecified successes in nonwovens. They also claim to have considerably strengthened their position with viscose in nonwovens in the last few years.
- With regard to the high hemi pulp for lyocell from Weyerhauser, AS believe the resulting fibre is unsuitable for high quality yarn production, but agree it would be suitable for nonwovens. It works well in the melt-blowing, centrifugal spinning and fibrid work they have done.
- Alceru’s work on cigarette filters is proving interesting to the Chinese. They have used both the tow and the nonwoven routes to tips. However the Chinese will not scale up the work until a viable local production of staple for textiles has been established.
The Chinese Nonwoven Market:
The following statistics have been compiled by
extracting data relevant to nonwovens from information on the total technical
textiles markets presented in the paper from Mr Xu Pu of CNITA.
The Chinese nonwovens industry has an annual capacity of
600,000 tonnes and in 1999 produced 350,000 tonnes of roll-goods. Production is
growing at 10% per year. Total output of the Chinese man-made fibre industry was
6 million tonnes in 1999.
Looked at by sectors involving, but not exclusively,
nonwovens:
Geotextile output (for infrastructure
construction) is now 20,000 tonnes/year and will reach 100,000 tonnes by 2010.
Only 5-10% of this is spunbond: woven split-film products being the leading
material in China at present.
12,000 tonnes/year of waterproof civil
engineering fabrics, either needled staple or spunbonded PET reinforced
bitumen, are now used. This will grow to 30,000 tonnes/year by 2010.
100,000 tonnes of cement reinforcing
fibres will be needed in 2010 in an attempt to stop cracking. None are
used currently.
Medical and hygiene fabric output is
currently 220,000 tonnes and expected to reach 300,000 by 2010. However this
appears to include woven bed-linen.
Production of cigarette filters from
acetate and PP is 130,000 tonnes and is expected to rise to 200,000 tonnes by
2010.
Paper machine press felt production -
15000 tonnes in 2000 - would reach 20,000 tonnes by 2010. Current local
production is not good enough for the faster paper machines so China will invest
to correct this.
Of 150,000 tonnes of Artificial
Leather, about 85% is woven, coated and sueded. The remaining 15%
(22,500 tonnes) is split between needlefelt and spunlace.
Technical textiles including nonwovens
now use 15% of Chinese fibre production, compared with 32% of Japan’s, 28% of
the USA’s and 20% of Europe’s. By 2010 the Chinese figure will be 23%. (Glass
fibre is excluded.)
The problems China has to be address in the next 10
years were listed as follows:
- The lack of capacity for advanced fibres such as aromatic polyamides, ultra-high strength PE, polyimides, polyphenylene sulphide and high strength carbon.
- The lack of flash-spun nonwovens like Tyvek.
- Tencel, PEN and PTT fibres need to be developed in China.
- There are too many small uneconomic plants. (574 producers of nonwovens have a total of 1000 production lines. 60% of producers make less than 1000 tpa. There are only 9 nonwoven plants with a capacity in excess of 5000 tonnes.)
- Locally made paper machine felts are not good enough for the newer machines. They will develop BOM felts (“Base Of Mesh” – sounds like scrim reinforced)
- Recent floods indicated underinvestment in geotextiles, and this will be corrected.
- They will do more new product development.
New Developments in Japanese Fibres
Tatsuki Matsuo, a Japanese Textile and Composites
Consultant provided an overview of new developments in his country’s technical
textiles industry:
- Teijin have developed coloured fibres without using dyes or pigments. The fibres are made up of what appeared to be 30-70 alternating layers of two different clear polymers with differing refractive index. Colour is generated by interference, is bright and metallic, changes according to the viewing direction, and is controlled by layer thickness. He called it the butterfly-wing fibre.
- Kuraray’s Kuralon KII PVOH staple is made in 3 forms, soluble, high tenacity and easy fibrillating: to bind nonwovens, to reinforce cement and to reinforce rubber respectively. They plan to have a 25,000 tpa capacity within two years.
- Toyobo’s Zylon (Polybutylene oxazole fibre?), developed using a Dow polymer has twice the strength and modulus of para-aramid and a limiting oxygen index of 68 oC, making it the most heat resistant organic fibre (decomposes at 650 oC) Applications mentioned were optic cable tension yarn, conveyor belts for glass and aluminium melt processing, ballistic protection, hot-gas filters and sails.
- Asahi’s Planova cellulosic virus filter passes plasma particles less than 10nm but catches HIV which is 10-100 nm in diameter.
- Ultra-fine fibres for HEPA filters, oil-water separation and blood-cell separation continue to be developed by Toray and others.
- Dr Suzuki’s Japan Absorbent Technology Institute will commence the production of “Mega-Thin” absorbent core material this summer. The new sheet is made from 100-300 micron superabsorbent granules bonded with microcrystalline cellulose and a little pulp. It has twice the absorbency per unit volume of conventional cores.
- Kuraray’s anti-fouling yarns are based on a bicomponent fibre with a high tenacity core and a biodegradable resin sheath containing antifouling agent and a leachability control agent”. They appear to be targeting fishing and mariculture markets.
NMMO Process possibilities
Ralph Bauer of Alceru Schwarza reviewed the various ways
of dissolving cellulose before describing the possibilities for taking the NMMO
route forward.
- Very fine fibrillation-free filament yarns (40 dtex/30 fils) were possible alternatives to nylon in luxury hosiery.
- Good results are being obtained in cigarette filters, but the route used was not spelt out (tow? Paper?)
- Composite materials reinforced by using higher modulus fibres or filaments.
- Utilising the high strength to allow the fibres to be filled with very high levels of functional materials e.g. conductive particles, ceramics.
- Direct production of nonwovens by spunbond or centrifugal spinning as described in Weyerhauser patents.
- Production of fibrids by hydrodynamic spinning rather than wet-grinding of short fibres.
Tandec Promotion
Professor Larry Wadsworth’s overview of Tandec’s
facilities and programmes, and of developments in spunbonding and meltblowing,
encouraged more questions than any other paper. The key points to emerge were:
- Tandec Technology Licencing, formed to manage the Exxon melt-blown patents donated to UTK three years ago, has consolidated and renewed their main contracts. These are with Accurate Products in the USA, Reifenhauser in Germany and Kobelco (A division of Kobe Steel) in Asia. They can only manufacture in their respective territories but all three can sell anywhere. These licensees have a co-operation agreement but AP is one of three manufacturers of MB equipment in the USA.
- Reifenhauser III is not always preferable to Reifenhauser II spunbond technology so Tandec intend to stay with II rather than upgrade. The faster spinning speeds used on III are producing a harder, more crystalline fibre which some feel gives a harsher nonwoven.
- 50% of Tandec’s running costs are covered by Exxon. Corporate members, about 30 in number cover the next 30% of costs, each paying $15,000 per year membership fees and getting 5 days “free” time on the pilot lines. The shortfall of 20% has to be made up from non-member trials ($6,000 per day) and testing and consulting services.
Recycling Plastics
Mr Paul X Ju of Erema Austria described their plastic
waste recycling machines, and dealt with the difficulties a manufacturer of
waste recycling machines has in an era of low virgin polymer prices. The basic
line for clean mixed olefin waste of the non-gassing variety, with or without a
pre-shredder generates enough heat in the cutter compacter zone to save energy
in extrusion. Typical conversion costs would be 5 to 8 cents/lb. To cope with
gassing from moisture, coatings and spin finishes a degassing system is required
and the costs rise to 6-10 cents/lb. As wastes get dirtier, more sophisticated
filtration systems are needed. Their self-cleaning laser-perforated metal disc
filters remove particles above 150 microns and cope with the 5-10% aluminium or
copper foil that typically contaminates yoghurt pots, jam beakers and cable
waste. These were even more expensive. In an extension to this paper that was
printed but not presented, he described a modification to prevent PET oxidation
problems caused by spin-finish residues in the recovered product. This involves
cutting and melting under high vacuum to remove 80-98% of the finish thereby
eliminating the viscosity loss in the process.
New Tyvek Application
Jimmy Wang of Dupont Shanghai described how
Tyvek could be used to replace bitumen-based roofing felts and
reduce condensation problems. Insulation blocks fitted between
the beams of a ridge roof are covered with a Tyvek layer on the outside and a
Tyvek/spunbond laminate inner layer. The inner layer was less permeable than the
outer layer, so the cold outer layer could easily transpire the moisture getting
through from the warm side. The tiles had to be mounted on spacers to allow
outside air to ventilate the outer surface of the Tyvek for it to work. The
diffusion rate of the outer Tyvek was put at >3.5kg/sq meter/hour.
Geotextile Strength
Mr Fang Qing of the Tianjin Petrochemical Corporation
had studied the factors affecting the strength of a 300 gsm needlepunched
geotextile. Unsurprisingly, increases in fibre strength (2.7 to 3.5 CN/tex),
fibre length (40 to 75 mm) and reductions in fibre denier (20 to 3 dtex) all had
a significant and roughly linear effect on nonwoven strength. Crimp level proved
irrelevant, but an optimum in strength curves occurred when needling at 500
punches/sq.cm using a needle penetration depth of 1 cm.
Perfojet Spunbond
Since their acquisition by Rieter, ICBT Perfojet has
been renamed Rieter-Perfojet and is now signing contracts for
the first sale of their Spunbond – Meltblown lines. The
melt-blown offering is based on a technology agreement with Kasen of Japan.
Their line includes no new inventions: the objective is simply to eliminate all
the known problems of existing lines. The key steps involve modular
construction, the use of three independently controllable zones between jet and
conveyor, gaining much better control of air temperature both in drawing and in
the plant as a whole, and providing easy maintenance and user interfaces. The
spunbond line produces 225kgs/hr/m from a single beam on PP at 1.7 dtex. MD/CD
ratio obtained is 1-1.3. It uses 1kw/kg energy.
Test Methods
The Institute Textile de France (Lyon) carries out some
unusual tests in characterising geotextiles:
- In biaxial testing of fabrics, loading MD and CD simultaneously, they use a CCD camera/computer to track the movement of a grid of dots marked onto the fabric before loading commences. There are significant differences between uniaxial and biaxial tensile results.
- An assessment of durability is obtained by two methods, creep testing and accelerated UV ageing. Both have been validated by comparison with fabrics exposed naturally over 380 days in Lyon.
- Creep testing involves using the biaxial testing equipment to load the fabric and monitoring the dot movements over 1000 seconds. They find that testing at 115 oC allows 1000 seconds to replicate 1 years natural creep.
- Both mercury vapour lamp (SEPAR) UV exposure and 1 year natural exposure testing has been applied to samples of HDPE, LDPE, PP, PET and PVC Coated PET, with and without UV stabilisers. FTIR spectroscopy is used show up the loss of antioxidant with exposure time and hence allow the calibration of the UV method.
- Agrotextile wind resistance and anchor point strength is measured in a wind tunnel.
Carbon for Concrete Repairs
China has a real problem with premature
deterioration of concrete structures so Mr Yue Quingrui of the National
Diagnosis and Rehabilitation of Industrial Building Engineering Research Center
described their trials with carbon fibre surface reinforcement. The carbon fibre
sheets and epoxy resin used to bond it to the concrete have so far been imported
from Japan. Starting with the first pilot project in March 98 they have
completed 50 building repairs and expect to use 20,000 sq.meters of CFRP sheet
this year. They bond the sheets to beams, slabs, columns, roof-trusses etc and
find it performs much better than glass-fibre reinforced sheet. They are now
moving on to bridge repairs and are also investigating the use of carbon fibre
rods to replace steel rods in new structures. Chinese carbon fibre producers are
now hoping to gear up to take over production of the necessary higher
performance fibres.
More Efficient Fishing
Ultra High Strength ropes and nettings
based on ultra high molecular weight polyethylene can allow fishing fleets to
consume less fuel or catch more fish. If the strength benefit is used directly,
bigger trawls can be used at greater depths, opening up new deep water fishing
grounds. Used indirectly in more conventional fishing, the lower drag arising
from the smaller diameter ropes and yarns allows significant savings in diesel
fuel. Last year the Chinese fleet used 1.7 million tonnes of diesel to catch 14
million tonnes of fish. Trials in the US and Europe were suggesting a 15-25%
fuel saving for UHSRN. Mr Le Wei of the East China Sea Fisheries Research
Institute estimated that China needed 534 tonnes/year of UHSRN for the fishing
fleet. If large-scale fish farming was considered, much larger cages could be
constructed from the stronger fibres, and a further 550 tonnes/year would be
required for this sector.
Other points from the CINTE Exhibition
- Dupont Asturias is still not working properly and is still running trials to meet the drape and gown market specifications. Off spec. product is being sold as wipes.
- Eastex , an offshoot of the China Textile Academy have a new 1.6 metre wide Perfojet HE line. Spinnbau cards feed an Autefa cross-lapper. Their brochure also shows a 0.5 metre wide Perfojet development line.
- Hangzhou Tian Li Water Jet Nonwoven Co. have a 1.6 metre wide Taiwan Spun-Lace Group machine fed from Chinese cards via an Asselin cross-layer. They appear to be concentrating on artificial leather from splittable synthetics.
- Acordis Industrial Fibres were promoting their industrial yarns in anticipation of their JV with Wuxi for an expansion of their industrial polyester filament plant. A letter of intent has been signed and a project proposal approved. Feasibility studies are starting (technological and market aspects). They expect contracts to be signed and a business licence granted by the middle of next year. Colbond, Acordis’s spunbonded polyester is not involved.
- The Hainan Xinlong stand was offering water-soluble HE nonwovens designed to dissolve at above 80 oC. They also had repellent nonwovens, wet-laid and HE'd chitin fibres as "artificial skin", pure-cotton nonwovens, HE'd silk nonwovens, anti-microbial nonwovens, non-adherent nonwovens for wound dressings. Their "Skin Comfort Webs" were said to use new process technology to create laminates comprising a hydrophobic topsheet, absorbent middle layer and a "functional layer" which could be any of the above nonwovens.
- Thibeau has installed 1230 cards, 421 of them for nonwovens, since starting in 1970. Associate company Asselin have installed 680 needlelooms in the same period. Their biggest loom, the A50 is 7.1 metres wide, runs at 1400 punches per minute with a 60mm stroke and uses 200,000 needles. The linking of Thibeau cards and Asselin crosslayers in the new computer controlled “Pro-Dyn” web-forming system give dramatic reductions in web weight variability. Fibre savings amount to 6.9% as a result. Since launch at ITMA last year they have sold a system to Japan.
- Smith and Nephew displayed their advanced polymeric nets and reminded us that they were the original inventors of the "emboss and stretch" process licenced to J&J (Delnet) and Applied Extrusion Technologies. (The RN30 product looks remarkably like Dri-weave). Their Op-Site breathable bacteria barrier films were of a similar vintage and now marketed in various speciality dressings. To make Op-Site they mix about 5% of high-impact polystyrene into polyurethane. This forms weak spots which can be opened in a stretching process to form micropores. Their CICA CARE scar-dressing is a heavy silicone gel dressing made under licence from Dow Chemical.
- EMS-Inventa-Fischer were promoting their versatile spunbond line, first introduced 2 years ago. They have just completed their first installation in “Nonwovens Phillipines” in Manila. They claim true versatility to make PP, PET or PA fabrics, the first line making PET products in the 8-120gsm range for filters, wrapping, technical uses and protective clothing.
- Andre Vuillaume “father” of Rieter-Perfojet reported concern from his customers that viscose shortage was now holding up the expansion in baby-wipe production, and hence the further expansion of HE capacity. He says that without exception all the users of his lines are close to full capacity. He has installed 8 lines in China, but here baby wipes are not important. They make drapes, gowns, masks, shoe covers protective clothing and artificial leather. His private concerns about the Rieter take-over relate to their ability, as a quoted company, to keep up with the fast-moving privately owned Fleissner operation. Nevertheless Rieter are better than most being very wealthy and having an industrial (as opposed to financial) vision of the future.
Footnote to Cinte:
The overall organisation was excellent compared with
Anex, all papers appeared in the proceedings, and all in both English and
Chinese. Unfortunately the simultaneous translation at the conference was poor.
It worked only when it wasn’t needed i.e. when the speaker stuck rigidly to the
text in the Proceedings. Questions were only occasionally interpreted, the
result being that non-Chinese delegates were unable to extract full value.
There were 160 delegates at the conference and 120
stands at the exhibition. English translations were, with few exceptions, only
available on the non-Chinese stands.
CRW May 30 th 2000
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