Natural paints: Difference between revisions

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Natural paints avoid indoor air pollution and can have an unusual, attractive appearance.

Introductions

This page describes natural paints as a potential component of United States of America home construction.

A Brief History

Creating durable, beautiful paints out of natural ingredients is not a new phenomenon. For millenia, people have been using the materials around them to create paints to color their worlds. Examples of natural paints can be found in the earliest cave drawings. They can be found in the world's most prestigious museums. And they can be found in the average home.

Over time, synthetic, toxic and energy-intensive materials -- such as formaldehyde -- were added to the paints that people use in their homes.^[1] These materials weren't added specifically to cause harm, but that didn't lessen their harmful effects. Some of these materials include synthetic dyes to increase color choices, additives to combat mold, and non-water-based binders such as petroleum products and heavy metals which were designed to withstand high use areas like kitchens.^[2] A notable expample is the lead-based paints that were once popular, but have now been linked to serious health risks.

But interest in natural paints has recently resurfaced in the face of growing concern for our environment, bringing people back to the techniques and materials that have stood the test of time. Still, it is important to understand that "natural" doesn't automatically mean "non-toxic" or "safe." Please use the information on this page to help inform your decisions about which natural paints are best for you and your home.

Below are examples of natural paints in action: beautiful, durable, and eco-groovy.

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  A fresco from a house in the ancient Roman city of Herculaneum. Likely painted with chalk, charcoal and colored earth on damp lime plaster, this style of fresco did not require a binder in the paint to adhere to the wall.^[3]

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  Madonna and Child by Duccio, 1284 A.D. This painting is tempera, an egg-based paint, and gold on wood. Tempera paintings are very long lasting, and examples from the first centuries AD still exist.^[4]

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  Leonardo DaVinci's The Last Supper, 1495-1498, is a great example of the beauty and durability of egg-based tempera paint. ^[5]

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  Colin Campbell Cooper's Flatiron Building, 1908, is casein (milk-based paint) on canvas.^[6]

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  The Scream, or The Cry by Edvard Munch is casein, tempera and wax crayon on cardboard.^[7][8]

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  This piece is created in the Nirmal style of painting. Named after a town in India, even modern Nirmal paintings remain true to the traditional techniques, including using natural ingredients like tamarind seed, herbs and mud.^[9]

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  Students at Humboldt State University use egg paint to create this logo for the interior wall of the Campus Center for Appropriate Technology.^[10]

Natural Paint Basics

Paint generally has three main ingredients or parts.

• The first part is the pigment, which is responsible for the color of the paint.^[11]

• The second part is the solvent. The solvent keeps the paint in liquid form and evaporates off as the paint dries.^[12] Solvent can also be used during the painting process to clean paint spills and correct mistakes.^[13]

• The third part of paint is the binder, which, as its name suggests, binds the paint together. This is the main body of paint.^[14]

• A fourth, optional component of paint is a filler. Fillers can be used to manipulate the texture and consistency of paint, and to reinforce the binder.^[15]

See also: Natural paint basics

Drawbacks of synthetic paints

VOCs/Indoor Air Quality

• Volatile Organic Compounds, or VOCs, such as those found in synthetic household paints can cause physical irritation and/or damage including irritation of eyes, nose and throat; headaches; loss of coordination; nausea; liver, kidney and central nervous system damage; and some are carcinogenic and can cause cancer in animals and humans.^[16]

• Common organic pollutants (including VOCs)have been found in higher concentrations within the home than outside. ^[17]

• Paints labeled "no-VOC" and "zero-VOC" can still legally contain up to 5g/L of VOCs.^[18]

• Modern "lead-free" synthetic paints can still have as much as 0.06% lead which scientists fear could be harmful to small children, even at low levels. ^[19]

Waste

• By volume, household paints account for a large portion of household hazardous waste in US homes.^[20]

• Household latex paint, oil-based paint and paint thinner are considered "hazardous waste" by the EPA. ^[21]

• Although considered less detrimental to health and the environment than oil-based paints, latex paint contains hazardous ingredients such as acrylics, vinyls and epoxies.^[22]

• In California specifically, latex paint must be disposed of in a Class I hazardous waste landfill. ^[23]

• Oil-based paints commonly containt petrochemical products as a solvent.^[24]

• Until 1990, mercury was used as an ingredient in oil-based and latex household paints. Leftover oil-based and latex household paints from before then may contain mercury, and oil-based paints that are several years old may also contain lead.^[25]

• In the UK, the government also classifies household paint as "hazardous waste." ^[26]

• Because synthetic household paints contain hazardous ingredients, they cannot be thrown into a regular garbage can. Depending on the type of paint, the disposal process may include tedious drying-out processes, finding a recycling center that accepts paint or locating hazardous waste collection programs. ^[27]

• People with unused or leftover household paints that can be classified as hazardous waste are encouraged to donate, return or swap paint to reduce waste.^[28]

• Even in production, it is estimated that for every 1000 kilograms of synthetic paint produced, 10,000 kilograms of waste are created. For specialty paints, this can be as high as 30,000 kilograms of waste.^[29]

• Titanium dioxide is a key ingredient in synthetic paints, and must be mined and processed in environmentally damaging ways.^[30]

Impacts of natural paint

Advantages

• Using natural paint can reduce the amount of VOCs present in the home, improving indoor air quality.

• Natural paints are microporous, allowing the walls to breathe. Because moisture is not trapped between the wall and the layer of paint, there is no blistering or peeling.^[31]

• Natural paints do not use petroleum products and contain ingredients from sustainable sources.^[32]

• Because of their non-toxic, natural ingredients, many natural paints are biodegradable, easily disposed of and even fit for a household compost pile once dried. This reduces landfill mass, environmental pollution and disposal costs compared to synthetic paints.^[33]

Disadvantages

• Natural paints, especially store bought, may be more expensive than synthetic paints.^[34]

• Natural paints may be more difficult to work with than synthetic paints because of texture, rate of drying and inconsistent coloring from batch to batch.^[35]

• Although anecdotally durable and resistant, there is a lack of performance data on natural paints, so it is important to test natural paint before commiting to a contract.^[36]

Products and recipes

Types of Natural Paints

Water-based paint

Water-based paints are the best choices for an environmentally-friendly solvent. Distemper and lime wash are two popular examples.^[37]

Casein or Milk paint

Casein paint is made from a protein commonly found in dairy, and is often called "milk paint" or "milk-based paint." This paint is mold resistant, durable and compostable.^[38] However, if not allowed to dry properly, milk-based paint can sour or mold.^[39]

Tempera or Egg paint

Egg-based paint is durable and quick to dry. It dries to a glossy finish.^[40]

Flour paint

Flour paint, though thich and tough on brushes, can be used on a wide range of household surfaces including wallpaper and drywall.^[41]

Oil-based paint

Commonly made from linseed oil, natural oil-based paints are durable and have a velvety texture.^[42]

See also: Natural paint basics

Recipies

Distemper Cellulouse Paint^[43]

Introduction

Whereas Size Paint uses animal glue, Cellulose Paint is plant-based. Its advantage over Size Paint is that it can be painted in layers. However it is still not for bathrooms or kitchens with high humidity. Cellulose Paint is an exciting medium for pigments, allowing their full beauty to be realized, as the pigments will sit on top of its surface giving the greatest light refraction. It can also be thinned to create a semi-transparent color wash. It is not high in opacity or hiding power.

This paint is easy to remove when a new coat of paint is desired as it is not permanent. To create a permanent paint, follow the instructions given with our Acrylic Resin for a 20% solution and use this for the water portion of your paint recipe after priming. Nontoxic, no VOC and permeable.

• Inexpensive and easy to mix
• Velvety smooth texture that can be layered
• Use on absorbent walls with a thin cellulose primer
• The look can be manipulated by choice of application tools

Primer Recipe

Ingredients

• 3 tblsp Methylcellulose Powder
• 8 cups water

Paint

Ingredients

• 6 tblsp Methylcellulose Powder
• 8 cups water
• 1¾ cups of prepared Whiting
• 6 tblsp Pigment

Step 1: Prepare the Chalk Whiting by covering it in water and soaking it overnight. This "fattens" the whiting by wetting all the particles. The water is then poured off and discarded and only the soaked Whiting is used in the quantities in your recipe.

Step 2: At the same time you can slake or soak the pigment, working it with an equal volume of water to create a homogeneous paste.

Step 3: It is most important when soaking the glue powder to sprinkle the powder into the water and not the other way around. Stir while sprinkling to ensure even dispersion. Allow the glue to stand and swell for at least 30 minutes. This step can also be done the night before if desired.

Step 4: Once the glue has completely dissolved, stir in the prepared whiting and the pigment paste until thoroughly incorporated. Let the paint stand for another 30 minutes. When ready to paint, you can pour it through a sieve or nylon stocking to remove any lumps. Thin your paint with water if necessary.

Always test samples to be sure the pigment does not powder off, indicating not enough binder. If it cracks or peels, increase the whiting and pigment ratio. Apply in one to three coats over the primer, drying for 6-8 hours between each. Use crisscross strokes. Effects can also be obtained with this paint, depending upon the applicator used. Clean up with soap and water. This recipe will cover approximately 150 sq ft.

Oil Paint for Wood^[44]

Introduction

Oil Paint dries slowly, and stays flexible. This allows it to expand and contract with wood. This recipe is for bare, unfinished wood and begins with a priming coat.

Oil Paint Primer

Ingredients

• 1 part Boiled Linseed Oil
• 1 part Iso-Pure Safe Solvent, Citrus Solvent or turpentine

Mix together thoroughly. (1 cup each of solvent and oil will cover approximately 30-40 sq feet depending upon how much oil is absorbed by the wood.) Paint on and allow it to soak in for 10 minutes. Use a lint-free cloth to wipe off any excess. Let the primer coat stand overnight before applying the first coat of paint.

Oil Paint

Ingredients

• 2 parts Boiled Linseed Oil
• 1 part Iso-Pure Safe Solvent, Citrus Solvent or turpentine
• Pigment in a starting ratio of 6 tablespoons to each cup of oil. (This will depend upon which pigment is used as they will absorb oil differently)

Create a paste by pouring a small amount of Boiled Linseed Oil into the pigment and blending until smooth. Slowly add the rest of the oil, then the solvent. This paint must be stirred constantly during use to keep the pigment dispersed. Your first coat of paint must be thin to avoid a skinning over that would prevent the paint from drying properly. Each subsequent coat should be applied after two or more days. Always work, and allow paint to dry, in a well-ventilated area. Note: Citrus Solvent will dry the quickest, Iso-Pure Safe Solvent will have the slowest drying rate. These two solvents can also be mixed together to create the same solvent used in our Boiled Linseed Oil.

Casein Borax Paint^[45]

Introduction

This paint is suitable for absorbent surfaces. It can be oiled or waxed so it can be wiped clean.

Basic Recipe

Ingredients

• 5 parts Casein Powder
• 9 parts Cold Water
• 2 parts Borax
• 9 parts Hot water
• 3 to 5 parts pigment (test ratios)

Sift Casein into water and soak 12 hours or overnight. Add hot water to Borax, stirring until dissolved. Stir this mixture into the casein and allow it to sit for at least one hour, possibly longer, until the Casein particles have all absorbed. You should have a yellow, translucent mixture. Heat this mixture to 140 ºF using a double boiler then allow it to cool. It will become syrup-like and can then be mixed with pigments.

Pre-wet your pigments with water and add the casein syrup to the pigments until you have the right proportions. This will depend on the pigment used and color desired. Be sure to do the recommended testing to be sure the casein/pigment ratio is correct. If it powders, add more binder. If it cracks, add more pigment. Thin this paint with water for use.

Quark and Oil Glaze^[46]

Introduction

This glaze is a sophisticated variation on the milk paint theme, allowing for beautiful effects of layering one or alternate colors over another. Use on absorbent surfaces, white for a base background or the color of your choice. It also makes a wonderful topcoat over milk paint (lime or borax type) to deepen the color, make it more waterproof, or provide a medium for special effects.

Ingredients

• Quark (see our Milk Paint recipe)
• 1 cup Boiled Linseed Oil
• 80 grams of pigment or Mica powders
• Water for slaking pigments and lengthening glaze

To create a glaze, follow the milk paint recipe to create your quark. For this amount (800ml of quark made from 1 gallon of milk) you would add 1 cup of Boiled Linseed Oil. Once your quark is created, rinse the curds with fresh water. Place them in your paint container and whip them with an electric beater while slowly drizzling in the oil until completely emulsified. Next add your pigment or mica powder that has been slaked (soaked) in an equal volume of water to make a homogenous paste. Once fully mixed, dilute with water to create a glaze consistency. Apply with a wide brush suitable for glazing. Each coat will take 2 or 3 hours to dry. Once complete, the oil in the glaze will take several days to completely dry. Wash tools in warm, soapy water. Glaze can be a wonderful medium for experimentation. Some pigments will work better in glazes than others, depending upon their transparency.

See also: Curdled milk paint recipe

Flour paint recipe

Examples of Manufactured Natural Paints

Manufacturer	Product	Qualities	Advantages
Ecotrend Paint[47]	Egg-based interior paint	Anti-mold Anti-bacterial 120 colors	No VOCs No harmful chemicals Odorless
The Natural Paint Company[48]	Natural primers Vegan primer Interior paints of chalk, lime, plant-based casein, marble powder and clay	Unlimited palette choice Stain-covering capability	No VOCs Organic Hypo-allergenic

See also

• Bottoms strawbale earthen plaster
• CCAT natural paint project
• Curdled milk paint recipe
• Flour paint recipe
• Natural paint basics
• Parras natural paint gallery

References