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03 Jan 2007  -  Germany

Use of natural fibres in composites for German automotive sector

Since 1996 the nova-Institut has been surveying data on the use of natural fibres (NF) in the German automotive production. In a comprehensive investigation by means of e-mail questionnaires and telephone interviews, the data for the years 2004 and 2005 were surveyed in the summer half-year of 2006. Like in previous years, here the data of the suppliers active in Germany were focused upon and could almost entirely be surveyed. Additional exemplary interviews of employees of automotive companies, NF mat producers, machine manufacturers and raw material suppliers served the purpose of further ensuring the data. 

Almost all data prove to be consistent with the surveys of previous years. However, the data
on the amounts of NF composites have to be considerably revised: The 45,000 t in 2003, as
published so far, retrospectively proved to be wrong, it was not before the year of 2005 that
30,000 t could actually be achieved – and this at a continuously increasing use. 

The reason for the miscalculation back then was the conversion of the natural fibre amount
into the composite amount. Here up to now - in coordination with branch representatives - an average natural fibre share of 40% had been presumed. But because for this year’s survey for the first time not only the natural fibre amount, but also the composite amount could be surveyed, the natural fibre share for thermoset and thermoplastic techniques could precisely be calculated now – and it is clearly beyond 40% (see below). In addition, for the first time also the edge trim was taken into consideration, with a presumed average loss of about 20% in the course of the moulding process. 

On the whole, given consistent data for the use of natural fibres, this results in newly calculated data for the respective composites. This correction was done retroactively for the
years 1999 till 2005, in order to obtain a new, coherent database.

In 2005, for the first time 19,000 t of natural fibres (without wood and cotton) were used in automotive composites. At the same time the shares of natural fibres used have changed.
While exotic natural fibres – jute & kenaf, sisal, coir and abaca – could increase substantially between 2000 and 2004 both on a percentage basis and absolutely, there has been a stagnation ever since. This is directly linked to the prices of European flax fibres that were quite high in the same period and have been decreasing again as recently as since 2004; simultaneously in recent years there were significant price increases for jute and kenaf on the world market. 

Accordingly flax could expand its market position again in the 2004 and 2005. The shares of
hemp are mainly determined by the short supply. Due to the failure of a large producer, the
use decreased in 2004, then recovering again.

Present market shares of different natural fibres
The following chart 2 shows the present shares of different natural fibres for the year of 2005 in the form of a pie chart. The predominance of flax fibres (market share of almost 65%) becomes clear which are almost exclusively produced in Europe, in most cases as by product of textile long fibre production. Hemp fibres, also almost exclusively from European
production, presently show a market share of just under 10%. Larger shares are possible not until further processing capacities will be established or the hemp insulation material market will decrease. 

For the year of 2005, “exotic natural fibres” could be itemised, what had not been possible in
recent years do the lack of respective data. The most important exotic fibres are jute and kenaf with 11%, followed by sisal with 7%. 

While jute is by far the fibre with the highest turnover worldwide, thus being the “leading fibre” amongst technical natural fibres, there are only little data available for kenaf. In the
trade sector, jute and kenaf are often not properly differentiated from one another. This is the
reason why these two Asian fibres are always listed together. Sisal is the second most
important technical natural fibre worldwide, mainly coming from Africa and South America.
Other exotic fibres are particularly coir from Southern Asia that are primarily used in
composites for high-class seats, and abaca fibres from the Phillipines that are used in a first exterior part in the framework of the press flow-moulding process. A couple of other natural fibres can be used for composites.

Excursus: Wood and cotton
In the framework of the survey, there was the attempt to also survey the amounts of wood fibres and cotton that are used in the German automotive production. Unfortunately, however, this was not possible in the framework of the investigation. 

As important companies from the wood fibre and wood flour processing sector did not take
part in the survey, merely about 16,000 t of wood fibres could be verified. In the framework of our market study of 2004, we had assumed about 25,000 t of wood fibres and about 36,000
t of wood fibre composites for the year of 2003. Because growth is generally expected for this sector, we estimate the amount for 2005 at about 27,000 t of wood fibres and about 40,000 t of respective wood fibre composites. 

The wood fibre composites used in the automotive industry have a large fibre content and an almost exclusively thermoset matrix. WPC granulates made from a thermoplast, wood flour and fibres respectively, as well as additives, constitute an exception. Their market share still is less than 1%, but will increase. 

The data for cotton are even sparser. Only a few hundred tons could be verified, although our previous study (2004) had stated about 45,000 t of cotton and about 79,000 t of respective composites for the year of 2003. 

This discrepancy is due to the fact that the survey was conducted primarily amongst passenger car sub-suppliers, while thermoset cotton composites today are almost exclusively used in lorry driver's cabs.

Natural fibres per passenger car
According to the Association of automotive industry („Verband der Automobilindustrie“, www.vda.de), 5.2 million passenger cars (2004) and 5.4 million (2005) respectively were
produced in Germany. Based on these figures, together with the data from chart 1 the average natural fibre amounts per passenger car can easily be calculated. For the years 2004 and 2005, this results in 3.6 kg/passenger car, a value only slightly higher than in 2003 (3.5 kg/passenger car). 

Natural fibre composites beyond the automotive industry
The interviewed automotive suppliers were asked whether they are also producing composites for other branches. Several small and medium suppliers affirmed this and together amounted to approx. 150 t that were mainly processed with PP-NF granulates using the injection moulding technique. The carrier material of grinding wheel is an example for this, with the aforesaid material successfully replacing PP glass fibre injection moulding material. 

Future developments
Regarding the future market development of natural fibre reinforced composites, there
presently isn’t any clear trend noticeable. Estimates are wide apart within the automotive
branch. There is belief on the one hand that natural fibres have already passed their peak and their applications will decrease, and on the other that there is a stabilisation with a (slight) market growth and interesting potentials in the medium term. “No clear direction for NF materials: Successes in the past, weakening at the moment, and an interesting future” – this is how an insider summarised the current situation in the summer of 2006. 

Also the material choice of OEMs and tier-one supplier is hard to assess, depending on the
series of models, decisions pro and contra natural fibre reinforced composites are made at the NF Market Study - 8 - nova-Institut, Dec. 2006 same time. At the moment, NF compression moulding is in a phase of stagnation, while NF press flow-moulding and PP-NFinjection moulding are increasing, however, based on a (yet) very small level.
 
It is clearly noticeable that the setting for new materials has substantially changed in recent
years. Under heavily increased cost pressure for which also quality is partly sacrificed, since the year of 2004 new materials have had considerably more difficulties than before. Suppliers want to use existing processing lines to capacity and not invest in new machines. New materials shall be better and cheaper, what can hardly be achieved. 

From an economic point of view, NF and wood materials exhibit decent price stability, being  less dependent on the mineral oil price than other materials, particularly if large NF and wood shares respectively can be realised. Should CO2 emissions be financially punished more severly in the future, further economic benefits would come about.

Compression moulding
NF compression moulding is an established and proven technique for the production of
extensive, lightweight and high-class interior parts in medium and luxury class cars. Advantages (lightweight construction, crash behaviour, deformation resistance, lamination
ability, depending on the overall concept, also price) and disadvantages (limited shape and
design forming, scraps, cost disadvantages in case of high part integration in construction
parts) are well known. Process optimisations are in progress, in order to reduce certain
problem areas such as scraps and to recycle wastage. By means of new one-shot compression moulding presses, also soft surfaces can be directly integrated, what has not been possible so far with injection moulding. 

As far as preferably inexpensive door concepts with a high part integration are concerned (up to the point of doing without lamination), NF compression moulding does not have good
chances against injection moulding. As far as high-class door concepts are concerned, NF
compression moulding remains to be a first choice technique. Against this background, it is
not astonishing that NF compression moulding is stagnating right now in the German
automotive industry. The decreases among small and medium suppliers are presently fully
compensated by increases among large tier-one suppliers. A structural problem is the fact that there are only a few compression moulding machine manufacturers and mat producers, that compression moulding is a specialised technique (dependence!). The suppliers would preferably use their existing (injection moulding) line to capacity. Under a heavy price pressure, this can become a disadvantage for NF compression moulding presses. 

The future of NF compression moulding depends on numerous factors (price pressure,
strategies, and interior concepts of the OEMs and suppliers, mineral oil, plastics and glass
fibre prices, advancement of compression moulding as well as correction concepts and
materials respectively). We assume that this technique will find its markets also in the future. 

This is also indicated by the fact that presently more NF compression moulding lines are installed worldwide than ever before – not in Europe, but in China, India and Iran. There, in
view of the current world market prices for natural fibres, NF compression moulding seems to be regarded as economically interesting and seminal technique.

Political framework
A favourable political framework could help bio-materials experience considerable growth.
For example forced measures for the reduction of CO2 emissions are to be mentioned here. In this sector, particularly natural fibres can score well, the production of which is ten times less energy-intensive than the one of glass fibres. 

A new EU End-of-Life Vehicle Directive, which is under revision at the moment, could also have a big influence. If attempts were successful to achieve a renewable resources deduction at source like e.g. the steel quota, as representatives of the natural fibre branch have been claiming for years, there would be considerable advantages for natural fibre reinforced composites. A practical solution could be that the actual share of renewable resources is credited to each vehicle as material recycling – regardless of whether the part is used energetically or materially. 

This approach would be justified by the fact that even in case of burning the renewable resources shares, the CO2 balance would almost be neutral. Right now this would merely result in 3.6 kg natural fibres per vehicle on the average; but vehicles with considerably larger amounts of 20 or also 30 kg have been successfully produced in series for years and could credit these amounts in the future, according to the model mentioned above.
 
A respective revision of the End-of-Life Vehicle Directive would cost Bruxelles nothing and
have crucial steering effects.

Source : nova-Institut