Puupinnoille soveltuvien ulkomaalien testaus ja vertailu - Theseus

Helsinki Metropolia University of Applied Sciences Abstract
Author
Title
Number of Pages
Date
Marjut Kuusisto
Testing and comparing exterior paints for wooden surfaces
228
6 May 2010
Degree Programme Materials Technology and Surface Engineering
Degree Bachelor of Engineering
Instructor
Supervisor
Raimo Soininen, D. Sc. (Tech.)
Raimo Soininen, D. Sc. (Tech.)
The subject of this final year project was to test and compare different kinds of exterior
paints which are suitable for wooden surfaces. The aim was to rank 18 painting systems
in an order of superiority. Among those 18 painting systems were both tradition paints
and modern paints from various producers.
The experiments were done at the surface treatment laboratory of Helsinki Metropolia
University of Applied Sciences. The properties examined were permeability to water,
water vapour transmission rate and durability against variation of temperature. The
effect of accelerated weathering test (QUV) on these properties was also examined.
In addition to these experiments, the washability of paint coatings was tested and the
contact angle of water was measured before and after QUV from the top of the paint
coatings. The weather durability of painting systems was tested in natural weather
conditions after about five months’ strain. Changes in colour and gloss were examined
in context of different tests.
A separate task in this project was to examine the occurrence of mildew in specimens
which had undergone long-term strain in natural weather conditions.
The painting systems received points according their properties. On the basis of the final
points, the painting systems were ranked in an order of superiority. The prices of the
paints were also considered in the examination of the results.
According to the results, acrylate paints maintained their properties and their QUV
resistance is good. The results of red paints and red ochre paints weakened because of
QUV while the ranking of linseed oil paints improved. Nevertheless, linseed oil paints
were not ranked among the best paints. The results of the silicone oil paint advertised as
a modern paint were also poor.
The cheap paint was ranked remarkably high in comparison with more expensive paints.
Opaque wood finishes were found to be realistic challengers to paints on the basis of
their durability in the experiments.
Keywords exterior painting, wooden facades, weathering test, water vapour
transmission rate