Wüest M. 51 Wykes M. 82 Yamaguchi M. 17 Ybarra G. 129 Yubero F ...

JUNE 27 TUESDAY MORNING
JS1-TuM-.INV.4 FUNCTIONAL AND DECORATIVE REFLECTING LAYER
FOR AUTOMOTIVE LIGHTING IN VALEO. J. M. Trigo, R. Acuña, A. Lara and D. Teba,
Valeo Iluminación Martos, Calle Linares 15, 23600 Martos, Jaén. Spain.
The possible developments of metallization process for reflectors are restricted looking for the quality
(maintaining process parameters under control to avoid scraps, creating effective hydrophilic layers
to diffuse more an more fogging materials, homogenizing layers thickness) and productivity (reducing
cycle time, simplifying process steps, decreasing costs and so on).
Following the lean process design rules, the trend is to use short dimension machines as Pylonmet
(Leybold TM) having short cycle times for PECVD, employing classical materials, as Al for reflective
layer and silicone matrix starting from the monomer hexamethyl disiloxane as protective topcoat.
This new concept has the advantages of the sputtering system (material long life, good process
control for product quality consistency, better adhesion with higher layer density) and the advantages
of batch metallization (parts movement and unique chamber).
Many efforts are focused to multiply the decorative possibilities of bezels, some of them without reflective
coatings (mass coloured materials where decorated part is obtained directly by injection of
pigmented thermoplastics); some others employ coloured reflective coatings by changing the metal
itself, creating different chemical reactions with the same metal, giving different colours or with coloured
topcoat.
Paint is an usual choice to give decorative effects on bezels because the metallized pigments give us
some shining appealing surfaces. On some cases, competitive costs can be achieved in front of in
chamber metallization process. Less original effects are achieved masking partially part areas resulting
delimited lines between metallized and non metallized where is visible the natural colour of base
plastic.
The interaction of YAG laser (wavelength on near IR) and reflective coatings, bring us new and
original possibilities for decoration purposes, because laser removes the reflecting layer showing all
kind of patterns by contrast with coloured plastic substrate.
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