What Are Colored Pencils Made Of? A Closer Look At This Medium
What are colored pencils made of? It is a question that many artists ask, and the answer might surprise you. Wax (as a binder), pigments, and extenders compose the core or lead of the colored pencil, then the wood for the barrel. The type of wax used in colored pencils can vary, and extenders are used mostly to determine the hardness of the lead.
Different types of colored pencils have different compositions. Oil-based colored pencils have oil as a binder on top of the wax. Water-soluble colored pencils have less wax than regular wax-based colored pencils so that the pigments can blend with the addition of water.
What are Colored Pencils Made of?
Below are the basic components that make up a colored pencil. Note that the quality and composition of each of the components affect the overall quality of the colored pencils.
Pigments are what give pencils their color. High-quality pigments usually comprise the bulk of the price of colored pencils. Artist-grade colored pencils use more high-quality pigments with better lightfastness ratings and better core durability.
Colored pencils that students and newbie artists often use are cheaper because they have a lower concentration of less-than-desirable pigments. These colored pencils also have lower lightfastness ratings. Most erasable colored pencils belong in this category.
Pure pigment is identifiable by its color index (CI names). There are two color sources for pigments - natural and synthetic, designated as N and P, respectively. However, there are also historic pigments without color index names.
Thus, when you see the CI name NY, you'll know this is a natural yellow pigment, while PY is a synthetic yellow pigment. An example of a pigment without a color index name is Limonite, a pigment extracted from bog ore and other natural sources and has a light brown to dull light reddish-yellow color.
For example, to make the color brown ochre, PY42 (Yellow Iron Oxide), PR101 (Synthetic Iron Oxide Red), and PBk9 (Bone Black) are the pigments used. Green ochre, on the other hand, uses PY3 (Hansa Yellow), PY42 (Yellow Iron Oxide), PY13 (Benzidine Yellow), PO62 (Benzimidazolone Orange), and PBk6 (Carbon Black).
Binders also come in different types - wax, oil-based, and water-soluble. When mixing pigments with binders, manufacturers ensure that they're using the proper type to get the quality they desire.
Wax as a binder is more common than oil and water-soluble binders. The most commonly used waxes are paraffin, beeswax, and carnauba wax. Beeswax and carnauba wax are more sustainable to use, but paraffin, as a by-product of petroleum products, has the most impact on the environment.
Wax-based colored pencils are easier to break because the core is softer and lays smoothly. The downside of wax-based colored pencils is the tendency to produce a wax bloom. Wax blooms appear as a powdery coating on top of the colored pencil resulting from thickly applying wax-based colored pencils.
Manufacturers also use oil as a binder for colored pencils. However, the binder is not entirely oil but a combination of oil and wax. This type of composition gives stronger colored pencils with a longer lifespan. It also eliminates the issue of wax bloom. However, these colored pencils are also pricier and harder to apply than wax-based colored pencils.
Gum Arabic is the binder of choice for water-soluble colored pencils. Aside from gum Arabic, these colored pencils also include an emulsifier that liquifies the pigments to achieve the watercolor effect. Unlike wax and oil-based colored pencils, the pigments in water-soluble colored pencils are suspended within the composition and settle when dissolved by applying water.
Manufacturers' most common extenders for their colored pencils are kaolin, talc, or chalk. Kaolin, processed from kaolinite (an industrial mineral), has several uses in manufacturing paper, ceramics, rubber, and colored pencils. Talc is another clay mineral used in baby powders, ceramics, paint, and cosmetics. Chalk, on the other hand, comes from seashells and limestone deposits.
Kaolin and talc are naturally available but have a finite source. Also, environmentalists contend that extracting kaolin and talc releases greenhouse gasses. Of the three, only chalk has the least impact on the environment and is renewable (though the process is slow).
The amount and quality of extenders added to the colored pencil's composition determines how the colored pencils apply. For example, colored pencils that apply with a soft buttery feel have less amount of extenders, while those with harder core use more extenders.
Wood is an important factor in making colored pencils. Most manufacturers use farmed wood to protect the natural forests and mitigate the environmental impact of cutting trees. The tree should be solid enough to not bend under pressure, yet easy to sharpen.
Some of the most commonly used wood are several kinds of cedar, basswood, and Caribbean pine. Other woods used are poplar, beechwood, abachi, white fir, jelutong, and vatta wood.
However, some manufacturers started making woodless colored pencils to lessen even the harvest of farmed trees. Instead of wood, woodless colored pencils use a clear lacquer coating. Environmentalists think that wood is more sustainable and has less impact on greenhouse gasses than using lacquer coating, a by-product of petroleum.
What Makes Each Colored Pencil Type Unique?
Each colored pencil type has a unique composition. Professional colored pencils have higher concentrations.
Conventional Colored Pencils
Conventional colored pencils, also known as student-grade colored pencils, have more pigment and extenders. They are also cheaper than other colored pencils. Most standard colored pencils use paraffin wax as a binder and chalk as an extender.
Wax-Based Colored Pencils
Wax-based colored pencils are basic among professional-grade colored pencils. They use different kinds of wax (beeswax, paraffin, carnauba, and cellulose ethers) as binders. Professional-grade colored pencils use either talc or kaolin as an extender, but the amount of extenders is lesser to maintain the vibrant colors and quality of the pigments. The soft core of wax-based leads makes them easy to blend colors.
Oil-Based Colored Pencils
Oil-based colored pencils use vegetable oil in addition to wax as a binder. The colored cores are more expensive than wax-based pencils and have a harder core due to adding oil to the composition.
Erasable Colored Pencils
Erasable colored pencils have more extenders, usually chalk, making the pigments less attached to the paper, thus making them easier to erase. Most erasable colored pencils are good enough for younger students and artists. In addition to being erasable, these colored pencils have an attached eraser, making them look like ordinary graphite pencils.
Water-Soluble Colored Pencils
Water-soluble colored pencils, also known as watercolor pencils, are unique because they react with water, thus dispersing the pigments within the gum Arabic used as a binder. Professional artists love using these colored pencils for mixed media art.
Metallic Colored Pencils
Metallic colored pencils are special because they contain a glittery sheen, owing to the mica powder. The shiny surface of metallic colored pencils is best for adding a whimsical feature to your colored pencil drawings.
Woodless Colored Pencils
Woodless colored pencils have the same composition as wax-colored pencils. However, as the name implies, they don't have a wood casing. Instead, they use a lacquer coating to keep the woodless colored pencils from disintegrating when used. Sometimes, a colorless foil covers the individual pencils.
The advantage of using woodless colored pencils is you get as much as 3 times the color because the whole pencil is pure color. You can also use the shavings from sharpening these pencils to smudge your colored pencil drawings.
How are Colored Pencils Made?
Mixing the core
Everything starts with the core or lead. In this process, the manufacturer mixes the ingredients for the core - pigments, wax, binders, extenders, and water. For primary colors, the manufacturers use single pigments. For secondary and tertiary colors, chemists and color specialists compute the amount of each pigment to get the right colors.
The amount and quality of pigments dictate the vividness of the colors. Each colored pencil contains one or more pigments that you can mix and match to determine the colors of your colored pencils. We will devote a separate section to discussing the pigments used for making colored pencils.
Another reason you should get colored pencils with quality pigments is that it affects the lightfastness of the colored pencils.
The extenders (kaolin, talc, or chalk) and binders (cellulose ethers or vegetable gums) make up the bulk of the composition. The more extenders and binders there are, the harder the core and the cheaper are the colored pencils. The wax and water keep everything together to make a mixture of an even and smooth consistency.
Extruding & drying the core
After mixing the pigments, an extruder machine extrudes the mixture. The extruded core hardens so it keeps in shape. A cylindrical metal container with holes holds the extruded core using a separate container for each color. The leads are then placed inside a warm oven, though not hot enough to melt the wax.
Preparing the wooden barrel
A machine shapes and cleans the woodcut to the length and fits 6 cores, approximately 8x4 inches. Most colored pencil manufacturers use farmed trees planted in company-owned plantations and plant more trees for every tree they harvest.
Cutting the groove on the barrel
From the machine that cleans the pencil slats, a conveyor belt transfers the wood to the machine that carves a groove that will fit the core of the colored pencil. A pair of these grooved slats are assigned for every 6 cores. The grooves should be aligned so both sides will fit together perfectly.
Applying the glue
Before adding the core to the colored pencils, a machine applies glue to the groove to attach the core to the barrel. Gluing the core to the barrel ensures that the core doesn't separate from the wood, especially when sharpening the pencils. You can observe that cheap and low-quality colored pencils do not have a stable core or the core that is not properly centered.
Assembling the colored pencils
Another machine glued the other grooved wooden slat to the one with the core to assemble the colored pencils. The machine presses the slats down with enough pressure to prevent the pencils from disintegrating when made into individual pencils.
The conveyor drives the assembled colored pencils to the drying wheel. Here, the wheel turns the colored pencils and uses natural heat and air actions to dry the glue and stabilize the core for reshaping. The glue and the core must be adequately dried and stable before shaping them.
Shaping the pencils
After the drying process is complete, the next step is to cut and shape the pencils into their iconic hexagon shape (though other brands use round or triangular shapes). A machine with a large blade shaves off any excess wood until the pencils are the perfect size and shape. It also makes the wooden barrel smooth and ready for the next steps.
The next step is the painting process. Most manufacturers use the same color as the core to paint the wooden barrel, while others use their brand's signature color scheme. As in mixing the core, chemists and color specialists mix the paint to get the right color.
Another machine loads the paint into a container with a hole that pushes the painted pencils into the waiting conveyor belt. The paint used for painting colored pencils is fast-drying, so the paint is fully dry in a short time while on the conveyor, while the pencils travel to the machine that stamps the markings. If the pencil has more than one color, it moves to the other machine that adds the second and third colors to them.
The stamping machine gives the colored pencils their identity and other markings such as brand and name or a number of the color. Other brands add information like the colorfastness scale and other similar markings. The markings may be in gold or black and, less commonly, in silver depending on the brand. The colored pencils may also get a gold or silver band around them added by the stamping machine.
Finishing the end of the colored pencil
The machine that finishes the pencils is the only machine with the pencils in a vertical position, arranged in a holder that dips the pencils into a substance that seals the end of the colored pencils. Most artist-grade pencils have a finished end to give them a professional look.
Instead of sealing the ends on erasable colored pencils, the finishing machine adds a metal ferrule and a pencil eraser to give you the convenience of erasing without needing a separate eraser. Some brands add the erasers only after the quality testing to ensure the pencils are of the best quality before adding the final touch.
However, most colored pencils have ends left bare, so you have the option to sharpen them on both ends. Sharpening on both ends allows you more control over your colored pencils since you can sharpen bluntly on one end and make a sharp tip on the other end.
Most colored pencils are pre-sharpened in the factory, so they're ready to use when they arrive at the customers. Pre-sharpening is a good test of how a pencil responds to sharpening and pressure. It also helps customers see the individual colors of the colored pencils.
Colored pencils undergo three tests - drawing endurance, pressure, and lightfastness - before the final inspection and shipping. Colored pencils must last at least 100 meters to pass the test. A machine does this test by filling in a pre-drawn shape calculated to be 100 meters.
Colored pencils should withstand at least 2.5kgs (5.5lbs) of pressure. A human tester presses the pencil on a weighing scale until it breaks in this test. Lastly, the lightfastness test to rate the lightfastness of the color.
Before packing the colored pencils, quality assurance personnel inspect the colored pencils individually to weed out the damaged, improperly stamped, or pencils with broken cores after sharpening. During this stage, the colored pencils are still grouped according to colors.
Several dispensers dispense the individual pencils during the packing process according to the number of colors that go with each pack. Sometimes, packers fill the boxes with colored pencils. However, some packers only need to seal the boxes since the machine packs the pencils directly into the boxes.
The packers then pack the boxes with colored pencils into larger boxes for delivery to stores.
When was Colored Pencil Invented?
Colored pencils started appearing in the 19th century when Staedtler started making oil-based colored pencils, a spinoff from wax-based crayons that the Romans used, as recorded by Pliny the Elder. However, during the early days of colored pencils, they were more for technical work than artistic work.
Less than a century later, colored pencils became popular for art projects, making companies like Faber-Castell and Caran d'Ache the forerunners of its invention and mass production in 1924. Other companies followed suit, trying to create the best quality colored pencils for their target market.
Water-soluble pencils, mechanical colored pencils, and even woodless colored pencils came into being, each one more improved and promising more benefits than the previous versions. However, artists are very discerning and choose only the best for their projects.
What is Lightfastness in Colored Pencils?
Lightfastness is the measure that artists use to designate the time it takes for a color to fade while exposed to UV rays from natural daylight or simulated daylight. Colors with a good lightfast rating last longer than colors with a low lightfast rating. Remember that a bigger rating means the color has poor lightfastness.
Also, manufacturers cannot perfect the lightfastness rating of their pigments because it is limited by the chemical structure of the organic pigment.
Different rating bodies rate the colors differently, using their specific metrics. For example, ASTM (American Society for Testing Materials) uses these codes to signify the lightfastness of colors:
Very poor lightfastness
Less than two years
Very good lightfastness
Over 100 years
On the other hand, the Blue Wool Standard lightfastness tests have 8 ratings. Fugitive colors mean they fade faster than colors with excellent lightfastness.
So what are colored pencils made of? The lead is a combination of wax, pigments, and extenders. Depending on the type of colored pencil as an art medium, there can be different binders used (wax or oil). Artists who want to know more about the materials in their favorite tools should look at the composition of each type of colored pencil. With so many varieties available on the market today, it pays to do your research.