Mildew-Resistant Coatings

MIL-HDBK-1110

5.17

Slip-Resistant Floors. A slip-resistant coating is

often applied as a finish for other coating systems to prevent

accidental slipping. The resistance is imparted by sprinkling

granules in the wet coating. MIL-E-24635 is used for alkyd

systems and MIL-C-24667, Coating System, Non-Skid, for Roll or

Spray Application (Metric) for epoxy systems. The MIL-C-24667

may also be used on alkyd systems where MIL-E-24635 may exceed

local VOC limitations.

5.18

Fouling-Resistant Coatings. Antifouling coatings are

often used over a coating system that imparts corrosion

resistance to ships or other structures to be immersed in sea

water. A toxic material, usually copper ion, is slowly leached

into the sea water to deter attachment and growth of biological

fouling organisms. MIL-P-24647, Paint System, Anticorrosive and

Antifouling, Ship Hull is normally recommended for this purpose.

It has a large list of qualified products. Such a copper-

containing product should not be used on an aluminum boat,

because direct contact of a copper product with aluminum will

result in accelerated galvanic corrosion. Commercial organo-tin

antifouling paints are permitted on aluminum boats. There are

restrictions on their use on large Navy ships.

5.19

Mildew-Resistant Coatings. Mildew growth on painted or

unpainted surfaces of buildings can cause unsightly defacements,

especially at tropical and subtropical locations. This occurs on

interior and exterior surfaces of steel, concrete/masonry,

asbestos-cement, or wood. Mildew can also damage delicate

communications and utilities equipment. In addition serious

bronchial problems may be associated with living in quarters

contaminated with mildew-covered surfaces. The different species

of microorganisms usually present in mildew growths include

molds, yeast, algae, and bacteria. These same organisms are

found on mildew-defaced surfaces throughout the world. The

darkly pigmented organisms are most conspicuous and contribute to

most of the defacement.

5.19.1

Factors Affecting Mildew Growth.

Factors that affect

likelihood of mildew growth include:

a) Weather - Higher temperatures and dampness promote

growth, and light inhibits it.

b) Building Design - Rough surfaces assist pickup of

spores and dirt, roof overhang keeps wall surfaces damp longer,

poor drainage, and porous substrates such as wood retain

moisture; alkalinity on concrete surfaces inhibits growth; and

air exchange, temperature, and humidity may control growth.

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