F

Fading
Loss of gloss or sheen.

Filler
Inert inorganic powder used as a filling phase in industrial paints and in some architectural materials. Provides extra body or hiding power. May be added in relatively large proportions to improve properties and/or decrease cost.
See Extender for architectural coatings

Film
Layer of coating.

Film forming aid
See Coalescing agent

Film forming process
Formation by drying of a solid and coherent polymer-matrix film from a fluid paint applied to a substrate. Drying can be physical drying (for coatings based on thermoplastic binders), chemical drying (for coatings based on reactive binders), or both.

Film integrity
Continuity of a coating free of defects.

Film preservative
See Preservative

Film thickness gauge
Equipment for measuring either wet or dry film thickness.

Fish eyes
Coating defect: circular voids or separation in the coating. Fish-eyes can be caused by oily spots or silicone particles and/or by air-borne droplets that are deposited on the painted surface.

Flame retardant
Additive which inhibits the initiation and/or spread of flame or smoke by inhibiting the combustion reaction in the flame, or by other mechanisms such as suppression of the oxygen flow and the build-up of protecting layers.
Syn. Fire retardant, Smoke suppressant

Flammable
Substance easily ignited in the presence of a flame; any liquid having a flash point below 100°F (37.8°C).

Flash Point
Lowest temperature of a liquid at which sufficient vapor is provided to form an ignitable mixture when mixed with air. Flash point is tested on a "Setaflash Tester" or a "Tag Closed Cup Flash Tester" (TCC).

Flash-off time
Time which must be allowed after the application of a coating before baking, in order that the initial solvents are released, which prevents bubbling.

Flash-rust inhibitor
Temporary corrosion inhibitor used in waterborne coatings to avoid corrosion during the drying time of the paint. This additive can also prevent corrosion of in-can aqueous systems during storage.

Flat
Surface with minimal reflection, commonly fewer than seven units of gloss when measured at a 60° angle.

Flexibility
Degree at which a coating is able to face a deformation of its supporting surface without cracking or flaking.

Floating/Flooding
Coating defect: concentration of pigments at the surface of the paint (floating) or in stains and patches inside the coating film (flooding). This defect leads to a change in color.

Flocculating agent
Additive used to control flocculation, and therefore to control paint rheology.

Flocculation
Particle aggregation in dispersions as a result of decreased colloid stability. Flocculation can be controlled and therefore can help to control paint rheology.

Flow
Ability of a wet coating film to level out after application in order to eliminate roller marks and produce a smooth uniform film.

Flow modifier
See Rheology modifier

Flow promoting agent
Syn Leveling agent

Fluid tip
Orifice in a spray gun to which the needle is seated.

Fluorescent pigment
Pigment which, when exposed to visible light, emits light of a different wavelength, producing a bright appearance. By absorbing unwanted wavelengths of light and converting them into light of desire wavelengths, these colors seem to possess an actual glow of their own.

Fluoropolymer
Polymer that contains atoms of fluorine.
Examples of fluoropolymers are PTFE and PVDF.

Foam
Dispersion of air bubbles in water. Foams are stabilized by surfactants. Foam formation takes place only in the presence of surface-active molecules of emulsifiers, wetting agents, dispersants, additives or binders.

Foam control agent
Additive used to control, inhibit (foam inhibiting agent), or suppress (defoamer) foam formation in water-based coatings. Foam inhibiting agents are added to the system whereas defoamers are post-added.

Foam inhibiting agent
Additive added in the paint formulation to inhibit foam formation.
See Foam control agent

Force drying
Acceleration of drying by increasing the ambient temperature.

Freeze/thaw stability controller
Additive used in latex paints to withstand freeze/thaw cycles without coagulation and detrimental effect on application properties or coating performance.

Fungi
Types of microscopic plant materials that are very numerous and occur in many different forms. Their spores, or reproductive bodies are everywhere and await only proper conditions of moisture and temperature to germinate, grow and reproduce.

Fungicide
Substance capable of destroying or preventing the growth of fungi. Fungicides do not provide any residual protection from future mould growth.
See Preservative, Biocide