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General
The chemical composition of smoke is dependent on the composition of
the material that is being burnt. As well as containing particulate
carbon, smoke can contain a wide range of staining substances both solvent
and water-soluble. It must always be assumed that both types of substances
are present in any smoke-damaged area.
Cleaning
Over the years, experience has shown that the most effective cleaning
is achieved by the use of Resene
Emulsifiable Solvent Cleaner. This is scrubbed on to affected areas
where it will dissolve up most of the solvent-soluble stains. The affected
areas are then washed with water, which emulsifies the stain-laden solvent
and dissolves the majority of water-soluble stains.
Surface preparation
Damaged surfaces, such as flaking paint, spalled plaster, should be repaired
as normal.
Selection of paint system
Not withstanding the above washing procedure, remnants of stains will
be left on the surface. A solventborne paint applied will block off
the water-soluble stains but transmit solvent-soluble stains; a waterborne
paint works vice versa. Combination of the two types of paints in the
one system is effective at blocking off both types of stain. Therefore,
if a solventborne finish is required such as Resene
Super Gloss Enamel, use a waterborne undercoat as first coat , such as
Resene
Quick Dry Acrylic Undercoat. Where a waterborne finish is required
such as Resene Sonyx
101, use a solventborne undercoat first. Resene
Aluminium Wood Primer is particularly effective.
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