Common Terminologies Used In Paint Production

For the sake of those asking me to make a post on how to make paint. I have decided to make a detail post on how to make quality pain in nigeria, but before then, I do like to discuss some common terms used in pain production; so that you won’t have any challenge when reading through my post on pain production. Below are some of the common terminologies used in paint making.

COLOR Paints are coloring substances.

COLOR Charts are often used for color identifications.

OPACITY OR HIDING POWER refers to the ability of the paint to obliterate the surface which it coats.

DENSITY is a measure of bubbles contained in a given volume of paint.

VISCOSITY is a measure of flow of the paint.

WETTING AGENT OR SURFACTANT is substance used to aid dispersion of pigments as well as promote and stabilize the emulsion in emulsion paints.

SEALER is a coating used when the surface to be painted is highly porous or can exude a material which will damage subsequent coats of paint. 

PRIMER This is the paint intended as the first coat on a substrate. It is often designed to perform as both primer and sealer. It functions to (i) give adequate protection to the substrate and will adhere to substrate or sealer, (ii) provide a surface to which the undercoat will adhere well. Primers are formulated according to the type of substrate to be coated, and a knowledge of the nature and behaviour of the various types of surface is indispensable to the paint formulator. In using primers, the secondary coating should be the type that would not chemically react with the primary coating thus removing it from the substrate.

UNDERCOAT, FILLERS AND STOPPERS This is the coating following the primer, and its main purpose is the obliteration and the coloring of the under the surface to which it is applied. Compositions known as fillers and stoppers may be regarded as parts of the undercoat. They are heavily pigmented materials serving as means of filling and stopping up pit and dents and similar irregularities of the contour of the surface, so that the surface finally prepared for the receipt of the finishing coat becomes uniform in texture and color and free from imperfections.

FINISH This is the paint that serves as the final coating on the surface, giving it the color it bears. It is, however, different from woodfinish, the application of which is rather preceded by sanding, sealer and filler which seal the pore on the wood.

VARNISH This is resin either (a) dissolved in or reacted with, drying oil and usually further diluted with volatile solvent, or (b) dissolved in solvent. It is specifically no paint, but serves a protective purpose of paints. It is applied to the underneath of boats.

INTERGARD This is a quick-drying catalyzed oil paint widely used in marine works.

SPLASH ZONE COMPOUND This is the material mainly used in marine works, especially in ships, where the pressure from the water as well as the contents of the sea water, like salt, and other weather conditions are tense. This normally results in corrosion which ordinary paints cannot prevent completely. It is highly pigmented and thick, thus avoids being lost in the application process (best achieved manually), lasts long and, most importantly, proves excellently adhesive to the substrate.

EMULSION OR WATER PAINT This is a water-based paint. The pigment is dispersed in the aqueous phase both polymer and pigment form distinct dispersed phases and should coalesce only in the film when the water evaporates.

LATEX PAINT The term latex denotes a suspension of polymer particles in water. Emulsion paints consist basically of a combination of pigment and latex, hence it is called latex paint. Water paints other than latex include whitewash, casein paint, paint and linseed emulsion paint.

WHITEWASH This may be made by mixing unslaked lime with water and allowing it to stand for a few days before use, or starting with calcium hydroxide in the first place. The applied coating converts to calcium carbonate. Certain additives, like glue, have been used for their cheapness.

CASEIN PAINT This is usually supplied as a powder to be mixed by the user. Casein is about 10-12% of the composition, together with some lime to convert it to insoluble calcium caseinate after application. The balance is pigments plus preservatives.

CEMENT PAINT This is used to a limited extent on masonry. It is supplied as a powder containing Portland cement and white or alkali-resistant coloured pigments. It is mixed with water for application.

LINSEED EMULSION PAINT This may be prepared from linseed oil emulsified by a combination of lipophilic and hydrophilic emulsifiers. The emulsified linseed oil is made into paint by formulae similar to those used for latex paints, except that addition of metallic driers is necessary. Onyenekenwa Cyprian Eneh A guide for the paint maker.

GLOSS OR OIL PAINT This is the oil-based paint. It is shiny in appearance.

ENAMEL The word enamel strictly means a glass-like substance fused on to metal surfaces.

EXTERIOR AND INTERIOR PAINTS Exterior paints are used to coat exterior surfaces, while interior paints are used to coat interior surfaces. Both organic solvent and emulsion types are made classes of paint. Considering solvent types only, there are a number of reasons why it is not practicable to use the same material for both exteriors and interiors. For example, linseed oil-based paints yellow severely when not exposed to light and outside weather.

CRACKING AND ADHESION Cracking is the break on the paint film that extends from the surface to the underlying material. It reflects a loss or lack of adhesion.

CHALKING, ABRASION, HARDNESS AND ADHERENCE These refer to the hardness to scratch or otherwise of the dry coating. Chalking is a progressive powdering of the film from the surface inward, caused by continued and destructive oxidation of oil after the original drying of the paint. Very rapid chalking is termed erosion.

FINENESS This is a measure of the presence of the unwanted particles or flocculated aggregates of particles in the paint.

CHECKING This refers to the slight fine breaks in the surface of a film visible to the eye or a 10-power microscope.

FLOODING OR FLOATING This is a defect involving the separation of individual pigment particles, thus giving a non-uniform colour. Onyenekenwa Cyprian Eneh A guide for the paint maker.

THIXOTROPY This is the property of a liquid or gel to lose viscosity under stress and regain the gel state when the stress is removed.

FLOW This is the ability of an applied film to level out evenly and produce a smooth coat.

LEVELING Brush marks are left behind immediately after the brushing of paint. These furrows or striations soon disappear due to the leveling of the wet film prior to drying. Acceptable leveling becomes important, since brush marks are considered as signs of weakness (incipient corrosion or cracking).

SAGGING If the paint is applied to a vertical surface a downward flow (due to influence of gravitation) takes place. This is variously referred to as running, curtaining, or sagging. A certain tolerable degree of this flow is necessary for satisfactory leveling, but excessive sagging is inexcusable.

BLISTERING This is usually the effect of the sun which heats and softens the paint coating and develops vapour pressure under the dried top layer from the volatile matter trapped by too rapid drying and skinning over the top surface of the film. The heat-expanded vapour causes the soft film to blister. The volatile matter in the film may arise from the resinous constituents of the wood carrying the coating, from solvent residues or from moisture. Onyenekenwa Cyprian Eneh A guide for the paint maker.

LIVERING This is the appearance in a paint of semi-solid, jelly-like masses resembling raw liver. It is caused by chemical reactions, which may occur between certain pigments and vehicles.

DRYING We can look at the drying of paints in a number of ways. The first is illustrated by the use of a pigment dissolved in a volatile liquid (e.g. Alcohol). When applied to a surface, the liquid soon evaporates and leaves the pigment matter spread over the surface in a thin, even, hard layer, which serves the desired purpose. The second is illustrated by the dissolution of the pigment in oil. The oil does not evaporate, but absorbs oxygen, and due to oxidation and polymerization, the liquid oil is changed into a solid, sufficiently hard and tough to protect the surface underneath. The third is the reaction between separate components of the vehicle. In this case, product may be supplied in two separate containers which are mixed just before use, to prevent solidification of the material in the package. A combination of these can also apply.

SKINNING Paints, after sometime, develop some thickening. This is known as skinning.

FREEZING This is the tendency to solidify or lose fluidity by stored paint.

GLOSS This refers to the specular reflectance or the light reflected at the same angle as the angle of incidence.