Paint and pigment: Colour and performance from design to delivery

by brittney_cutler_2 | April 4, 2022 1:00 pm

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By Rick Wilson

What is in a can of paint? Pigment choice considers more than colour alone. Paint can evoke certain feelings, both positive and negative, and plays a crucial role in the anticipated outcome of a space. The genetic makeup of a pigment and coating can provide desirable performance characteristics.

Understanding the history of colours, how performance is impacted by pigments, and getting back to the basics of paint will help specifiers select high-quality, innovative coatings in order to deliver meaningful benefits to their project’s owners and occupants.

A history of colour

The history of colour is told through the art, design, and fashions of the past. Throughout the years, colours have earned a reputation for evoking certain feelings due to specific roles in history. From insects, plants, and stones, people have been using the natural materials around them for years to develop pigments that span across the colour wheel to create art and bring emotions to life.

Red

Viewed as an exciting, dramatic colour, red draws attention, stimulates energy, and encourages interaction and confidence. It has more personal associations than any other colour and is often used as an accent in spaces. Examples of red pigments found in nature include carmine, brazilwood dye, and madder.

Blue

Considered universally appealing, blue creates a feeling of serenity and openness while encouraging communication and promoting interaction. In the past, blue pigments were rare in nature and only affordable to the wealthy, creating the association with aristocracy and royalty. The colour elicits a feeling of calm and aids in intuition. Azurite, indigo, and pollia condensate are examples of blue pigments found in nature.

Yellow

Associated with extremely positive emotions, yellow is the most visible colour, which is why it is often used for road signs and school buses. It is primarily linked with the sun, therefore positivity, happiness, and cheer are words often associated with this bright colour. Examples of naturally occurring yellow pigments include yellow orchre, naples yellow, and orpiment.

Green

Signifying a strong association with nature, green refreshes and restores. It is perceived as calming and serene. Green brings balance to the human brain and can have relaxing and renewing effects. Buckthorn, terre verte, and malachite are examples of green pigments found in nature.

Orange

Giving off an aura that is cheerful, bold, and exciting, orange is the colour of vibrancy. It is described as daring, joyful, and adventuresome. Examples of natural orange pigments include realgar, cadmium orange, and carnelian.

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Purple

Considered a luxurious shade, purple has both warm and cool properties which uplift and calm the mind. Depending on the shade, it can be exciting and energizing, or mysterious and mystical. Purple is also calming to the mind and nerves while encouraging creativity. Tyrian purple, hematite manganese, and caput mortuum are a few examples of this hue one can see in nature.

Black

A neutral, yet dramatic counterpoint to any colour, black is an authoritative, elegant, and classic shade that conveys sophistication. In all cultures, black has established itself as the quintessential colour of luxury and power. Examples of black pigments found in nature include vine black, bone black, and vantablack.

Brown

Known as the colour of earth, brown is a relaxed neutral that is easy to live and work around. It evokes feelings of wholesomeness, reliability, and naturalness, and can be used anywhere. Umber, mommia, and sepia are examples of brown pigments found in nature.

White

Symbolizing freshness, purity, and cleanliness, white is the sum of all colours. It typifies pure thoughts, encourages de-cluttering, aids in mental clarity, and enables fresh beginnings. Examples of white pigments found in nature include kaolinite, zinc, and titanium white.

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Brushing up on paint basics

Paint covers some of the largest areas in buildings, so it is crucial to understand how to specify the right paint for the job and why not all paint is created equal. There are four primary components of paint and each serves an important role in colour and performance. The raw ingredients and formulations can vary widely, with different choices resulting in different outcomes for each project.

Solvents

Solvents are liquids used to dissolve or disperse a polymer and reduce the viscosity in paint. A solvent provides no real added durability benefits and is simply the carrier that allows the painter to get the paint from the can to the surface.

Additives

Additives are extra ingredients to give the paint specific performance characteristics. For example, mildewcides and rheology modifiers improve the viscosity and application of the coating.

Binders

Binders affect everything from stain resistance and gloss to adhesion and crack resistance. Higher quality binders, found in higher quality paints, adhere to surfaces better and provide enhanced film integrity and longer lasting performance. Latex paints may contain multiple types of acrylic binders while oil-based contain linseed oil, soya oil, or alkyds.

Pigments

There are two different types of pigments: prime and extender. Prime pigments provide colour and hide. Titanium dioxide is an example of a prime pigment and it provides excellent light-scattering properties in applications requiring white opacity and brightness. Extender pigments can be lower in cost and add bulk to the coating but have little value when it comes to colour. These pigments may improve other paint characteristics, including clay, silica and silicates, and calcium carbonate.

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The final colour of the product results from a colour formula combining a base paint with colourants, which contain primary colour pigments compounded and dispersed into a liquid. Most colourants are added at the point of sale in accordance with a manufacturer’s colour formula for a specific coating.

To create a high-performing coating without sacrificing colour requires human and technical expertise to manage colour accuracy and consistency at every stage from product design, quality manufacturing, colour formula management, and final tinting. This is necessary to reduce the possibility of colour issues on the jobsite. Specifiers should look for coatings, colours, and colour formulas specifically designed to work as an integrated system. For example, colour formulas should be programmed to flex subtly and precisely depending on the product and finish combination specified, ensuring the most accurate colour results in the finished product. One way to ensure this is by working with a paint manufacturer with the capability to manage its own manufacturing and quality, as this will positively affect the colourants used to tint the paint.

Foundation of the paint system

Primers can play a critical role in the success of any paint system and help achieve the final topcoat colour. The primer is a hard-working component which establishes the initial adhesion to the substrate. Certain primers are formulated to block stains, resist corrosion, assure adhesion, allow the finish coat to develop a full and consistent sheen and maintain a topcoat gloss, and act as a surface filler.

For certain deep, vivid, or transparent colours, a grey primer achieves accurate colour match in fewer coatings, better touch-up, excellent hide, a more uniform colour with less streaking, and bolder and brighter colours, resulting in increased customer satisfaction.

It is common to see specifications that call for one coat of primer plus one or two coats of a topcoat, but this may fall short of what is needed to achieve a suitable hide and the desired finish with deep tints and accent colours. Instead, it is important to keep in mind that deep and accent clear-base colours may require one to two more coats to achieve the proper hide. A primer is necessary because it helps contactors avoid applying additional coats of paint, saving them time and money and avoiding issues like uneven paint film or peeling.

How pigments impact performance

Beyond esthetics, pigments can also provide desirable performance attributes. The type and quality of prime pigments used in the base paint will affect the coating’s performance in four areas: hide, durability, fading, and the gloss or sheen.

Hide is the ability of a paint to obscure the surface upon which the coating is applied. It is created by the light-absorbing or light-scattering properties of pigments. From a practical perspective, “dirtier” colours tend to offer a better hide in fewer coats. Specifiers should look for high-quality paints with an optimal primer for the topcoat colour to achieve deep, clear, bright, and translucent colours.

Durability is measured by how well the paint film resists physical degradation from use and environmental conditions, such as abrasion, chemicals, scrubbing, washing, staining, moisture, and UV exposure. It is traditionally influenced by the binder or resin of the paint, as well as the gloss level. High paint-resin or binder levels create high sheen, smooth finishes, and durable surfaces. This is a result of the paint’s binder imparting adhesion, binding the pigments together and strongly influencing properties, such as gloss, weather durability, flexibility, and toughness. High paint pigment levels along with course pigment granules create duller, rougher, and less resilient finishes. When colour has worn off the paint film from repeated cleaning, this is called colour wash-off and it is a result of pigment particles being exposed at the surface. Coatings rated with higher durability will retain their colour and gloss, no matter how many times they are washed.

Fade resistance is typically referenced in regard to exterior coatings since these are exposed to UV rays and other elements. However, interior paints can also fade or lighten when the surface is exposed to significant sunlight. As the coating ages, the fading can become more noticeable and while slight fading is acceptable, some paints can begin to develop chalking—when the painted surface comes off—causing the colour to appear lighter. Certain pigments are inherently better at retaining colour, hence why specifiers will generally have a broader range of colours for interior products than exterior because interior colourants used outside will fade.

Gloss and sheen are two aspects of the same element. Both strongly impact how a colour or finish looks and can significantly affect how the eye sees it. Gloss and sheen are measured by reflecting light off specific angles. Gloss is measured at a 60 degree angle—meaning a beam of light is deflected from 60 degrees off of a surface and back into a receptor. The receptor provides the number of gloss units, from zero to 100. The closer the gloss units are to 100 units, the shinier, or glossier, the paint. Sheen is measured at an 85 degree angle.

Dark glossy finishes tend to look darker than their matte counterparts while light glossy finishes skew brighter and sharper. The intensity and direction of the light source should be factored in as well. Matte colours tend to look darker viewed from an angle or in low light and can also look quite flat when viewed straight on and only seem lustrous from an angle. Glossy finishes can look lighter or slightly mottled if the surface is rough, uneven, or has other imperfections. It is also important to understand that sheen and gloss are not mutually exclusive—some paints have a gloss value, some have a sheen value, and some have both.

Here are some tips for specifying a product’s gloss and sheen to ensure the end result meets client expectations.

Flat

Typically less durable, flat and matte finishes offer zero to very low reflectance when dry and can hide imperfection in the substrate.

Satin

Slightly more durable, low gloss, low sheen, low lustre, and velvet finishes offer low to medium reflectance when dry. Satin finishes can minimize glare in spaces with lots of lights.

Semi-gloss

More durable than satin and flat finishes, semi-gloss, pearl, and medium lustre finishes offer medium to low-high reflectance when dry. Semi-gloss offers a tough, washable, and stain-resistant finish.

Gloss

The most durable, gloss and high-gloss finishes offer high reflectance when dry, and these finishes accent architectural features and create depth perception.

Specifying paint

When specifying paint, make the process easier and ultimately ensure a quality outcome on the job by keeping in mind a few key points.

Generic description

Interior or exterior, sheen/gloss and resin, or solvent.

Special characteristics

Zero VOCs, odour eliminating technology, moisture resistance, mould and mildew resistance, rust inhibitive, and abrasion or impact resistance.

Reference standards

Measurable and comparable performance standards and ASTM for hardness, abrasion resistance, and adhesion.

Basis of design

Establishes an enforceable level of quality, helps with submittal review, delivers what is important to the owner, and lists specific manufacturer, make, and/or model.

In order to specify the right coating and colour for the job, it is helpful to understand everything from the ingredients that make a coating to how those ingredients will affect the emotions and performance of a space. By following these tips, specifiers will ensure the project is done successfully and to their clients’ expectations.

[5]Rick Watson was with Sherwin-Williams for more than 30 years. He began his career in 1988, in the management training program. Shortly thereafter, he became a professional coating sales representative in Fort Wayne, Indiana. Since then, Watson has progressed through several roles of greater responsibility including store manager, product information team leader, product information manager, and director of product information and technical services before retiring in 2021.

Source URL: https://www.constructioncanada.net/paint-and-pigment-colour-and-performance-from-design-to-delivery/

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