Terms and Definitions

Alkyd
Binder
Coalescence
Diatomaceous earth
Dispersion
Disperse water/disperse oil
Emulsion
Environmental Conditions/Factors
Formulation
Gloss & Matte
Grinding
Latex
Pigment Evaluation
Organic VS Inorganic Pigments
pH
Polycarbonate
Polymer
Rheology
Thickeners
Solids Content
Wetting
Surfactant
Saturation
Solution vs Suspension

Troubleshooting Materials For Waterbased Paints

Antifoam
Ammonia
Wetting Agents
What "Hue" Means

HOW TO's

HOW TO MAKE BASIC WATERBASED PAINT
HOW TO THICKEN WATERBASED PAINT
DIRECTIONS USING DRY PIGMENTS
HOW TO MAKE EXTREMELY MATTE WATERBASED PAINT
DIRECTIONS FOR CREATING METALLIC EFFECTS

Alkyd: Our alkyds (long oil) are pigment concentrates that are compatible with oil or solvent paint bases. These concentrates are made of a synthetic resin which is formed from a monobasic fatty acid which is oily, a polybasic acid and a polyhydric alcohol. An oil or combination of oils, e.g., linseed, safflower, soya, etc. must be added to give flexibility to the resin. The amount of oil determines the “length” of the alkyd. Short oil alkyds are 33-47% oil. Medium oil alkyds are 48-52% oil. Long oil alkyds are 53-85% oil. Most solvent based house paints such as enamels are long oil alkyds, which are also most suited for artists’s paints.

Binder: A substance that "binds" or "cements" pigment particles in a cohesive fashion so the paint surface is joined to the material to which it is applied

Coalescence: To form a paint film, spherical particles need to deform, soften and fuse together as water evaporates. The term for this process is "coalescence." Additives called "coalescing solvents" are added to facilitate the softening process. The ease of coalescence, and thus the perfection of the paint film depends on certain environmental factors, such as temperature and humidity.

Diatomaceous earth: Silica-rich soft dirt, fine-grained and, porous, light-colored, and composed of the skeletons of diatoms (one-celled marine organisms with silicon skeletons).

Dispersion: Highly concentrated, free-flowing (viscous) stable liquids in which the pigment particles are suspended in water. Dispersions are produced by mixing dry pigments with water and other dispersing agents.

The advantages to using dispersions as compared to dry pigments are:

1) They are quick and easy to use.

2) There are no airborne particles, so they are safer.

3) Dispersions give far greater brilliance and tinting strength than dry pigments because they are more finely ground than you could do by hand.

4) With certain pigments, the fineness of grind allows for beautifully intense transparencies.

5) Since they are pure pigments concentrates, they give a cleaner, more intense color.

Disperse water/disperse oil: This is a surfactant that is excellent at wetting the surface of a pigment particle with the liquid component of the dispersion. A dispersing agent’s function is to deagglomerate the pigment by working its way up through the pores of the agglomerates to wet all the pigment surfaces and separate the particles. A dispersion, in and of itself, would be too slow acting. The grinding of pigments, therefore is an integral part of the dispersing process. Use no more than 5% of total volume.

Emulsion: A liquid in which particles are suspended, not dissolved. A good example of an emulsion is milk, in which water suspends many tiny spheres of a fatty substance which will not dissolve in water.

Environmental Conditions/Factors: Environmental conditions such as temperature and humidity can have profound effects on the paint drying process. Paint begins to crack somewhere around fifty degrees Fahrenheit. Painting in a very cold studio can result in cracks, brittleness, or paint that dries into a powder. On humid days, the quantity of water in the air can significantly slow the drying time, the paint begins to dry over trapped sections of water which can crack the paint film when the water begins to dry. A thick paint film can cause water (and the coalescing solvent) to soak into the absorbent substrate before the acrylic particles have time to fuse together. This may also result in cracks and surface defects. Be sure to allow at least 24 hours for a thin paint film to cure before applying another coat.

Formulation: Paint bases such as acrylic, vinyl or urethane are sold to paint companies in a raw, unmodified state. Formulation is the process by which certain chemicals are added to improve the performance of the binder.

Raw paint bases need additives so they:

1) Will form a non-cracking, non-brittle film

2) Have a better consistency.

3) Perform better in lower temperature conditions

4) Will not form pinholes, craters or other surface defects.

5) Will not develop bacteria

6) Are more suited to combine with pigments.

7) Can be thickened without seeding or "cottage cheese-ing."

Gloss & Matte: In general, the higher the solids content, the more glossy the appearance. To make paints matte, you have to add particles to deflect the light; any fine particles will do. If the particles are too fine, as in the case with a pigment dispersion, they will not deflect light well enough to matte out the paint. Conversely, if the pigment is too large, it will begin to "texture-ize" the paint (this can be a desired effect). Silica is the most common material to create a matting effect, since it is cheap and highly light absorbent. To achieve a brilliant dead matte, it is recommended that you use the dry pigment as the matting medium. This method is more expensive, and protective gear is necessary, but the result can be worth the time and effort.

Grinding: This is a technical term that refers to the mechanical breakup of pigment agglomerates into individual pigment particles which are completely wetted by the liquid vehicle that will not allow for particle-to particle contact. Our dispersions are ground in a three ball mill between 24-96 hours depending on the pigment’s properties.

Latex: Not to be confused with synthetic rubber, "latex" refers to a broad range of water-based paints, such as acrylics, vinyls and urethanes. In a latex paint, water surrounds tiny spherical solid particles of a resin (for example, an acrylic resin). The resin is composed of a polymer which does not dissolve in water but can, with the use of surfactants be suspended in water to make a stable liquid known as an emulsion. Latex paints are not solutions of binder in water. For example, a water color is not a latex paint because its binder, gum arabic is actually dissolved in water. As a latex paint dries, the spherical particles of a polymer resin come closer and closer together as the water evaporates, absorbing into the substrate.

Pigment Evaluation: Not all pigments are suitable for artist’s paint. Pigments are evaluated in the following ways:

1) Masstone/Undertone:

a) Masstone is the full tone of the pigment (or the saturated paint).

b) Undertone is the masstone in a greatly diluted state (glaze) or as it appears on white.

c) With white. This will show the adjacent color tone of the pigment.

2) Adjacent Color Tone: When considering color, think about how a rainbow blends gradually from shade to shade. For example, yellow changes gradually from orange to green. Orange and green are therefore adjacent colors to yellow. The most exact way to describe adjacent colors is to identify how far a shade comes to the adjacent color. Sometimes pigments have numerical references affixed to them. For example, Hansa 10G is a hansa yellow that is 10 points toward green, meaning that is it a very green yellow. The best way to see what adjacent color tone a particular color is moving toward, make one or two tints, preferably one medium and one very light tint. This will make the adjacent color tone obvious, as well as ascertaining the general cleanliness of the color.

3) Opacity: The degree to which a pigment obscures a substrate, also known as "hiding power."

4) Tinting Strength: Indicates how strong a pigment’s color is. This is measured by how effectively a certain amount of the pigment imparts into white which determines how much paint can be made from a given dispersion. Take, for example, the difference between Dioxazine Violet and Ultramarine Violet. A 4 oz bottle of Dioxazine will yield well over 1 gallon of paint, whereas 4 oz of Ultramarine will barely make a quart of fully saturated paint. Another consideration is that of the "fineness" of pigment particles, that is, how well a pigment has been ground or dispersed. This explains why a dispersion will make far greater quantities of paint when compared to equal amounts of a dry pigment.

5) Alkali Resistance: Some pigments, such as Manganese Violet or Prussian Blue are not alkali resistant and should be used as soon as they are made, or shortly thereafter. It must be mentioned that once a paint is dry, it is no longer alkaline because the ammonia has evaporated. (see - PH)

6) Lightfastness: The degree to which a pigment is able to retain its color when exposed to ultraviolet radiation. E.G., Pigments classified "fugitive" are not lightfast.

7) Weatherfast-ness: Other than light, weather conditions such as rain, snow or high humidity can also affect the performance of pigments. Cadmiums, for example, possess excellent lightfast properties but are not weatherfast and are therefore not recommended for outdoor use.

Organic VS Inorganic Pigments: A good way of understanding the particular nature of a pigment is by identifying it as an "organic" or "inorganic pigment."

Inorganic pigments are molecules based on one or more metal atoms, such as cadmium, cobalt, chromium, nickel, manganese, iron, titanium, zinc, etc. These are commonly referred to as traditional renaissance pigments. Originally, these pigments were found in nature and mined. Pure versions of these pigments are primarily synthesized, bringing prices down and availability up, as well as increasing the range of available tones. Almost all of the pigments in this class are identified by the predominant type of metal present in pigment, though certain names, such as cerulean have come to indicate a specific metal mixture, in this case cobalt and tin.

Organic pigments, on the other hand, are derived from vegetable, (indigo, madder, etc.) animal (Indian yellow, etc.) or artificially derived (alizarine, etc.) Organic Pigments generally do not contain metal atoms but rather carbon to carbon atom bonding and chemical groups known as "chromophores" (from the Greek word "chromos" which means color) which are the source of color in the organic pigment family. These pigments are fugitive to some degree, but advances in the later 20th century pigment technology have allowed these pigments to be produced synthetically, in a much broader range and with a greater quality than their predecessors.

pH: Scientists measure the alkalinity or acidity of a substance by determining its pH. 7 is neutral The lower the pH, the more acidic, the higher the scale on the other end, the more alkali.

Polycarbonate: a synthetic resin in which the polymer units are linked through carbonate groups.

Polymer: A compound whose molecule is formed from a number of repeated units of one or more compounds of low molecular weight. Many aspects of the behavior of paint can be understood in terms of the polymetric nature of the material.

Rheology: The relationship of viscosity to shear. Simply stated, it is the relationship of thickness to stirring. Water, for example, is a classic Newtonian study of rheology, meaning viscosity does not depend on shear. In other words, water will not become thicker or thinner with stirring or shaking. On the other hand, materials that contain polymers generally have some interesting non-Newtonian rheological properties. For example, these materials might be very thick when they have been sitting still but become thinner the more they are stirred or shaken. Such material is referred to as "thixotropic," which is defined as "becoming temporarily liquid when shaken stirred and returning to a gel state when standing."

Thickeners: These substances are otherwise called "rheology modifiers" and are generally some type of polymer. For water-based paints, there are a wide variety of thickeners, all of which give the paint different properties. For example, one thickener may give the paint body an extremely thick mass, while, another may increase drag brush, giving the paint a tacky, sticky or oil-paint type feel.

Solids Content: This term refers to the true amount of film-forming, non-evaporating resin in a paint base. Below are several advantages to using a high solids content in a paint base:

1) Less shrinkage of the paint film, since there is less water to evaporate.

2) Higher gloss.

3) Better adhesion.

4) Greater latex binding power which allows for increased pigment loadings.

5) Greater dilution is possible, making the material more cost effective.

The highest solids content in acrylics or vinyls is 65%, which means only 35% of the total volume evaporates. Acrylics most often used by commercial artist paint manufacturers generally have a solids content of 45-50%. Generally more water is added with the pigments or fillers, bringing the solids content down to 30-35%. This means 60-70% of the total volume of commercial paint evaporates, which tends to lessen the overall quality.

By contrast, oils such as linseed oil dry by oxidation rather than evaporation, which means they have a solids content of 100%. Alkyds also approach 100% solids content, since the monobasic and polybasic oils do no evaporate.

Wetting: A term that includes:

1) Penetration - for example, a primer penetrates into the pores of a canvas and paint penetrates into the pores of a primer, or liquid penetrates into the pores of a pigment agglomerate.

2) Adhesion - paint adhering to a surface.

3) Spreading - for example, paint spreading as if to stain a canvas wetted with specific wetting agents.

Surfactant: Otherwise known as a "surface-active" substance, is a chemical that aids in the wetting of a surface, or which acts at the boundary of any surface-surface interaction. A simple example of a surfactant is soap. Soap is a long molecule in which one end is hydrophobic and the other is hydrophilic. When you wash your hands, the hydrophobic end of the soap molecule attaches to the grease molecules and the hydrophilic end attaches to the water that, by its force detaches the grease from your hand. When it comes to surfactants that are used in paint, for example with the hydrophilic molecule in the middle and hydrophobic molecules on either end can do amazing things in terms of wetting surfaces.

Saturation: A paint is saturated with color when the color of the dry paint is essentially the same as the color of the pigment dispersion. The term "dry paint" must be emphasized, since acrylics and most urethanes appear to be white when they are in liquid form, but dry clear. In other words, wet paint tends to darken in hue significantly, particularly when it comes to darker colors. Pigment is added past the saturation point when a special effect, such as bronzing (a certain kind of iridescence), or an increased opacity or matte-ness is desired without the dulling of color obtained by adding white or filler. The paint should be tested when dry in these circumstances to ensure that there is enough binder in the formula to hold the paint together so it doesn’t flake off.

Solution vs Suspension: The difference between a "solution" and a "suspension" is best clarified by understanding the way sugar and flour react with water. Sugar dissolves in water, making a "solution." Flour does not dissolve in water. Rather, it continues to exist as discrete solid particles which are surrounded by water.

Troubleshooting Materials For Waterbased Paints:

1) Antifoam - (Shake well before using) Despite careful stirring, factors such as heavy humidity, adding too much disperse water, or with certain pigments, particularly flourescents, paints can tend to foam more than usual. In this case, add no more than one drop of antifoam per 1 oz. Add the antifoam, and let sit. Tap the sides to let the bubbles rise to the surface. Caution: Do not use too much antifoam, as problems such as cratering, orange peel, pinholes, etc. will occur, and cannot be corrected.

2) Ammonia - Non-sudsy, concentrated ammonia (you can find it in hardware stores) is an excellent all-around problem solving additive. If the paint is lumpy, too thick, not thick enough etc., try adding a small amount and stirring. Be careful. Too much ammonia can make you problem worse. It can also cause burns and injure your eyes.

3) Wetting Agents - There are specific reasons for using wetting agents.

i) They can stabilize thickened paint very much like ammonia.

ii) They can assist in solving problems of incompatibility, (e.g. seeding flocculation, separation between pigment and binder, creaming, etc.)

iii) They can recover a dispersion that has thickened into a gel, (in this case, add a little water, a little disperse water, and, if necessary a little ammonia, then shake hard for several minutes) or pigment dispersions that have settled.

iv) In the case of settling, (heavy inorganics tend to do this) there are two different types. A slightly settled dispersion is a case where there is minimal separation, and is corrected by shaking the bottle. A heavily settled dispersion is a circumstance that requires digging into the settled pigment with an implement, adding some disperse water and ammonia and shaking long and hard. In order to prevent further settling, add a few drops of diluted thickener #1.

v) Surface wetting agents improve a paint’s ability to penetrate a surface. This is commonly used for stain painting, for use with wetting fabrics for better paint acceptance, and to promote adhesion by better wetting of the surface to be painted. To use, dilute 4 oz into up to one gallon of total liquid. (use no more than 10 drops per 4 oz of paint) Pre-wet the surface and apply the paint while it is still wet. (be sure to wear gloves.) Caution. The surface wetting agent can cause the paint to de-thicken, or prevent the paint from thickening. Use extreme care. This product can injure your eyes and skin. Wear gloves.

Commercial artist paint manufacturers often label their paint colors as a "hue" of a color, for example, "Cobalt Blue Hue" because it is not in fact truly cobalt blue but rather pthalo blue (an organic pigment with far grater tinting strength) which is diluted and then given the opacity of a cobalt with the addition of fillers. Refer to the color index number on the side of the tube to know what color you are purchasing.

Paint = Binder (paint base) + Pigment dispersion

The binder you choose will determine whether the paint is glossy, matte, or semigloss as well as textured or level.

1) Place the binder in a mixing container

2) Add a squirt of dispersion, or until the point of saturation.

3) Stir carefully. Make sure not to stir too hard, or past the point of the paint being fully mixed, as this will cause too many air bubbles.

Once you have achieved the color you want, you can thicken the paint by adding a good squirt of Thickener #1 and stir. Caution: If you don’t add enough thickener, the paint will form tiny seeds rather than thickening properly. Stir rapidly in one direction along the side of the container without whipping the paint. (overstirring will cause foam) If the paint is not thick enough, add a little more Thickener #1 and continue stirring. If you add too much, however, it can become unusable. Once the paint has a smooth consistency, you can add a small amount of non-sudsy, industrial ammonia and continue stirring. This will give the paint a creamier texture. After you have added thickener #1, you can add Thickener #2 to achieve an oil paint consistency. Use less of it than the #1. If you use #2 by itself, you will give it a honey-like consistency. Fiberthick is a binder that is a mixture of acrylic 65 and microscopic particles of a reinforcing fiber. This allows you to build your paint far from the surface.

Regular waterbased matte binders dull a color significantly due to the presence of the silica matting particles, though the dulling is lessened with the use of our matte urethane. If you don’t mind the added expense, you can use dry pigment as the matting agent; this will give you a brilliant matte, which is essentially the same color as the dry pigment. First, make a crude version of a pigment dispersion, making sure there are no lumps or any dry powder. Next, add only between 10-20% of acrylic 65 or Urethane 32 - do not add too much binder, or it will be too glossy and you will have to start over. Mix the paint and do a test stroke on a piece of paper. Let the paint dry completely, take a dry rag or towel and wipe it across the paper. If a lot of color wipes off, you have not added enough binder, so add a little more binder and repeat the test. Once you have passed the dry rag test, try it with a wet rag keeping in mind that some color is to be expected.

For methods of using dry pigments (or other non-colored powdered additives) which require only as much mixing as is possible with a brush. These methods can be applied for solvent or water-based paints. It will not achieve the level of ground pigments, but can suffice.

Making the crude version of a pigment dispersion

Manual grinding with a glass muller on a glass surface is recommended (see- Grinding) Make a paste with dry pigment, water and disperse water for waterbased paints or dry pigment, stand oil and disperse oil for oil base.

From metallic powders, pearlescents or glitters: dry metallics such as bronze, aluminum, copper or gold powders should not be treated like dry pigments. Most of these colors will patina and change color as metals themselves do. Urethane 32, however will dramatically minimize this effect. Pearlescents and glitters are easier to mix than the metal powders. It is generally sufficient to add these directly to the paint base, though it is recommended to add a little disperse water to make the paint smooth. (Be sure to add enough of this material to achieve your effect, which is usually at least 20% powder) For metallic paste: Silver pastes are concentrates of aluminum powders or flakes dispersed in mineral spirits which are both compatible in oil or water due to the presence of a dispersing agent. E.G., 4 oz of silver sparkle will make 1 gallon of metallic paint. These pastes also have the advantage of not forming a patina, though they may dull over the years. You can create any gold bronze, etc effect by adding the appropriate transparent pigment to the paste. Put the paste in a container. For oil paint, add stand oil. Mix out the lumps. Add the color you want. For waterbased paint, scoop some paste out of its container, and add just enough water to mash the lumps out. The mixture should be a toothpaste consistency. Add more binder than water, 3 to 4 times more, then add the transparent pigments to get your desired color.