JEC COMPOSITES MAGAZINE - Issue #107 - August/September 2016 - 41

TRANSPORTATION
railway

lnnovative approach for
non-flammable transparent FRP

yuuki ito
Manager of product planning,
Production division
akihiko oyama,
President
Miyagikasei Co. Ltd.

Various non-flammability solutions are available for FRP materials, for
example the use of halogens, phosphorus or inorganic materials such as
ATH or silica, but when a high level of non-flammability is required, a high
amount of non-flammable additives is needed, resulting in FRP performance
problems (e.g. high viscosity at impregnation or lower strength).

The first trial development focused on a
lighting cover for the railway sector. Following the 2003 subway fire in Korea, the
Japan Railway Rolling Stock and Machinery Association ( JRMA) enforced stricter
regulations, so the upper side of railway systems could no longer use materials likely to
drip.
Polycarbonate (non-flammable thermoplastics) were used before this regulation
came into effect, but reinforced glass covers
or indirect lighting are now used.

Multilayer composition
The upper layer is made of synthetic clay
and the lower layer combines glass fibre and
a binder resin. A Claist® clay layer is used to
form an oxygen barrier to contain pyrolysis
outgas from the binder resin.
Claist® was developed by Dr. Ebina from
AIST (Advanced Industrial Science and
Technology), who studied barrier materials
for various gases (including oxygen). Miyagikasei cooperated with him to develop

Feature Transportation

iyagikasei Co. Ltd. conducted a trial using a hybrid system that combines synthetic clay and FRP with
a small amount of non-flammable additives
in order to develop materials with the same
performance level as usual FRP materials.
The use of this hybrid technology yielded
innovative results in terms of FRP performance. Figure 1 shows a LED illumination
cover for trains.

resins can be selected, resulting in the following typical properties:
- Non-flammable, lightweight, transparent
FRP when using glass fibre;
- Non-flammable lightweight, high-strength
FRP when using carbon fibre.

/ jec composites magazine

Fig. 2: Practical application
of EXVIEW in a subway station

Development of the lighting cover

Fig. 1: Introduction of EXVIEW by
newspaper Kahoku Shinpo

Outline of research and development
In recent years, interior parts used in the
transportation sector (railway, aeronautics
and automotive) have been required to offer
a high level of non-flammability. The hybrid
technology combining clay and FRP offers
many possibilities to meet these needs.
Several different types of fibres and binder

The main properties required for the lighting cover were:
- High light transmittance (over 60%, the
whiter light requires optical dispersion);
- Strength and weight (same as polycarbonate products).
The railway lighting cover is longer than
500mm and uses over 3mm thick polycarbonate to achieve the necessary stiffness.
But FRP products (glass fibre and binder)
have enough strength for a target thickness
of 2mm.

Fig. 3: Old type of polycarbonate cover

No107 August - September 2016

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #107 - August/September 2016