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 Mica in Paints and Coatings
CMMP's muscovite micas are important
technical additives to a number of specialist paints and coatings to increase
weathering resistance (durability, chalking, cracking…). They help to
improve anti-corrosive properties, protect against wear from sunlight and
heat and give a shine to the surface.
Properties
Barrier effect
mica is used to provide a barrier to the ingress of moisture and to assist
adhesion, so increasing corrosion protection. Reduction in the permeability
of films incorporating mica can be ascribed to the co-planar packing of
lamellar particles within the film, forming overlapping layers, which are
aligned parallel to the substrate. Lamellar particles packing forms a
barrier, by increasing the length of the pathway along which the water must
travel to reach the substrate.
Resistance to UV
mica protects organic binders from early degradation by light and UV
rays. An array of the flat platelets remains on the surface. This presents a
hard, coherent barrier, which protect the underlying resin by reflecting sun
radiation.
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UV shielding effect
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Paint film reinforcement
The platy structure (high aspect ratio) of CMMP's micas reinforces mechanically the
paint film, while providing a resistant shield. It helps to release some of
the internal stresses created during film coalescence, inhibiting mudcracking and crack propagation through the film.
Chemical resistance
CMMP's micas are
insoluble in water and have an excellent chemical resistance, unaffected by
strong mineral acids such as sulfuric and
hydrochloric, They are only attacked by concentrated hydrofluoric acid.
Therefore the laminar and inert nature of these micas in
resins present a formidable barrier to chemical attacks.
Dispersion
The platy structure of mica disperses easily within paint solutions
and improves the dispersion of the other combined fillers.
Coloration
CMMP's micas are white
muscovite micas and can be combined with suitable pigments to obtain a wide
range of colors. CMMP's micas containing paints gave similar
results when compared with the system without mica for contrast ratio,
brightness and yellowness, proving that CMMP's micas are not detrimental to the
optical properties.
Food
contact
CMMP's
micas are natural products and present no toxicity. They are in conformity
with the standard EN 71/3.
Prevent
chalking
Increase
film brushability
Provide
smooth and attractive surfacing
Improve
temperature resistance
Applications
CMMP's micas find application in
exterior and industrial coatings such as:
- Aluminium paints
- Anticorrosive paints
- Decorative coatings
- Emulsion paints
- Intumescent coatings
- Marine paints
- R.P.E.
- Texture paints
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Additional documentation
- Protective and Barrier effect of Mica in
Paints
For
additional information, please contact us:
CMMP
45, rue de Saint-Petersbourg
75008 Paris
FRANCE
Tel : +33 1 43 87 45 75
Fax : +33 1 42 94 96 32
E-mail : cmmp@cmmp.fr
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