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Tag Archives: knowledge base

In: Manufacturing

Acrylic vs. Oil: What Is Toxicity And How To Manage It

If you read an article about the VOC content of paints, you may have a valid question: why all these paints are not labelled as toxic? I’ll tell you more, all they will have a label “non-toxic”. The reason is that the term “toxic” is limited by ingredients that cause “adverse chronic health effects” and “acute and/or chronic health hazard”.  In other words, if acute exposure to a certain paint doesn’t damage your body enough to the stage when it’s unreversible, or medical assistance is needed, the paint is officially non-toxic, and it’s your responsibility to provide proper ventilation and use protective equipment (glasses, gloves etc.) 

However, paints that contain cobalt, cadmium, lead, nickel, and many other heavy metals and major harsh toxins have to be marked as toxic. The USA is much stricter in this matter and the list of ingredients that would have warning signs is much longer. You can find it here: https://www.p65warnings.ca.gov/

All these are reasons why MSDS for the same kind of paints usually split for paints that don’t have toxic pigments and paints contain them. Lists of colours described by “non-toxic” and “toxic” documents usually are included by manufacturers. 

For some reason, even the industrial paint industry has much clearer labelling and standards than artist’s paints. Most of them show a list of ingredients and disclose VOC levels as well as precautionary measures. Anyways, as each of us has only one body and we’re going to carry it until the end of the day, that’s our responsibility to take proper care of it. Let’s take a look at how to provide safety in the workplace.

Oil paints and toxicity

As we mentioned in the previous articles, most of the toxicity of oil paints comes from solvents. Turpentine and white spirits as well as tons of odourless variations of those drag toxicity to the oil painting process. Yes, solvents ARE hazardous, cause eye and skin irritation, and may cause drowsiness or dizziness. Solvents may be fatal if swallowed and enter airways. Simply DO NOT USE SOLVENTS! Solvents are OPTIONAL for oil painting.

Another source of toxicity comes from certain pigments. However, such pigments can be present in any kind of paint (oil, acrylic, watercolours, gouache, tempera etc.) and are not exclusively linked to oil painting.

Technically, if you avoid them your painting process is non-toxic. Some manufacturers may add solvents inside the tubes, but now it’s getting less and less common. However, I recommend checking MSDS just in case and choosing your brands wisely.

Oil paints dry slowly and release VOC slowly as paints dry, so give your artwork 6 months or more before having it in the bedroom. Even though the VOC level is quite low there, it’s better to be on the safer side.

Because oil is quite a flammable material it’s recommended to take extra caution and avoid painting close to fireplaces, working heaters and other places that have potential fire hazards. The flashpoint of linseed oil is about 93 Celsius. 

We will talk about the storage and cleaning up process in further topics.

Acrylic paints and toxicity

The same as for oil painting, watch for pigments used. If you are sure that cobalt or cadmium may harm you, then just ignore this part.

When people say acrylic is “water-based”, they associate this statement with safety. Yes, acrylics do contain water that carries all ingredients and pigments, but it’s not a base, it’s one of the ingredients. As the acrylic polymer dispersant contains styrene, an alkyl methacrylate or a mixture of styrene and an alkyl methacrylate, you should take measures that keep your workplace safe. 

Methyl methacrylate can cause skin, eye and respiratory irritation. As we discussed before, proper ventilation is required, unless you paint outdoors. Health authorities recommend typically 10 air changes per hour. If special equipment is used for ventilation, make sure it’s fire-proof as the methyl methacrylate vapours are highly flammable. 

Styrene is a chemical used to make latex, synthetic rubber, and polystyrene resins. When you breathe air containing styrene, most of the styrene will rapidly enter your body through your lungs and will be broken down into other chemicals that leave your body in the urine within a few days. The International Agency for Research on Cancer (IARC) has determined that styrene is a possible carcinogen.

However,  the most dangerous guy in acrylic paints is ammonia. According to technical information, ammonia is a flammable gas that may form explosive mixtures with air. It may displace oxygen and cause rapid suffocation. It’s harmful if inhaled and can cause severe skin burns and eye damage. 

For acrylic painters, health authorities recommend wearing protective gloves and clothing and using proper eye protection. Keep your paints away from heat, hot surfaces, sparks, open flames and other ignition sources. Avoid smoking, drinking and eating in the room. Use paints only outdoors or in a well-ventilated area.  

 

In: Manufacturing

Acrylic vs. Oil: What Is Inside The Paints

In this series of articles, I’d like to look at these two mediums from a professional and responsible artist’s point of view, thinking about the artwork itself and the impacts that working with these mediums includes. There is no straightforward answer to what’s better and I don’t think such a question can be valid; this article is aimed to make an informed choice for this or that art project. I’ll try to be as straight to the point as possible.

Oil Paints

Historically, oil paints are made from pigment and oil. However, fresh-made paints, especially if they contain mineral pigments, will start separating within a very visible time frame (some paints show separation even after a week from the manufacturing date). Copper Oxide pigments separate in 5-7 days, and earthy pigments, depending on their particle size, within 1-3 months. Organic pigments, due to their lightweight nature, may not show any significant separation even after a year of manufacturing. Pigment use is a separate topic, so I’m not going to pull it here.

As it can take 5 or even more years between manufacturing time and actual purchase and consumption time, manufacturers need to make sure that their paints are still presentable. So, to stabilize paints (depending on pigments) they use wax pastes as well as barium sulfate. To increase the quality of the painting and the elasticity of the film, some resins can be added. Usually, it’s turpentine gum (don’t mix it up with turpentine oil), dammar, mastic etc. To shorten drying time a small amount of turpentine oil may be added.

Some paints, depending on pigments and grade (studio, artist, pro) may have fillers that usually have a mineral nature: kaolin, marble dust, calcite, barite, talc, etc.

Professional paints have pigment, oil, wax, resins and a minimal amount of fillers.

Acrylic paints

Here, everything is much more complicated. Long story short, here is a list of ingredients:

  1. Pigment. The same as for oil. The different pigments used for acrylic and oil will be covered in a separate article. 
  2. Binder. It’s either acrylic dispersion or emulsion or both. They contain styrene and/or an alkyl methacrylate. The alkyl methacrylates used are methyl methacrylate, isodecyl methacrylate or stearyl methacrylate. Many terms, but all these can be simplified as monomers that form polymers after the carrier (water) evaporates.
  3. pH adjuster and dispersant. When we paint in acrylic, we expect that paint will be easily spread, and mixed with other colours. That’s why ammonia is an essential acrylic paint component. Pigments, as we know, are solid particles and tend to settle down on the bottom of the pain container with time. Ammonia helps to disperse the pigments evenly throughout the paint, thereby providing nice consistency and colour uniformity.
  4. Surfactant. These chemicals prevent paints from early cracking and provide an even drying process. Here we have ammonia again, glycerine, and propylene glycol.
  5. Fungicide. As acrylic has water inside and some organic and inorganic ingredients, paints need to have preservatives that stop mould growth. Here, it can be ammonia, formaldehyde, or petroleum by-products.
  6. Paints, that contain mica powder as well as very thick paints may contain solvent to prevent separation and prevent paints from drying in tubes.

Ingredients used in paints deal with safety and health issues. 

In: Brushes

Why Prices for Brushes Are So Different?

The market of art supplies now is full of chaos (maybe, it always was). Some paints or brushes cost just a few dollars, while others go all the way to $100 and up. Unfortunately, the price doesn’t always reflect the quality of the product, which, actually, creates a mess. Let’s talk about brushes and what we’re buying. I’ll make separate sections on different kinds of brushes with a brief overview. 

Kolinsky Brushes

Kolinsky Sable brushes are highly prized by artists for their quality, performance, and versatility, making them a popular choice among professionals and serious hobbyists. They work perfectly for watercolour painting and oil glazing techniques. And these brushes vary in price a lot. Really a lot. A round brush 3 mm in diameter can cost $2 or $50. These price differences are worth taking a closer look at why it’s happening, when we deal with a true value and when it’s just a game.

We already have an article about how to choose Kolinsky brushes for your goals , let’s cover just the pricing things. 

For brushes, the best and most valuable hair comes from the belly part of Kolinsky males grown in the wild in Siberia (Russia). It doesn’t mean that the best Kolinsky brushes have to be made in Russia. Nowadays, international trade is very developed, and brush manufacturers worldwide have good access to almost anything they need or want. The hair from belly part has relatively short and very springy hair with excellent water and oil absorbency. 

As only a limited hair source works well for paint brushes, it makes the brushes very precious. And the best brushes in this category (from what we carry) come from the Roubloff Premium series and Old Holland brand. These brushes are worth the price higher paid. 

Nevertheless, many manufacturers use other parts of Kolinsky’s sable to produce their brushes, which leads to quality drops. As the hair itself derived from the tail (for example) can be quite long to use or be very dry and brittle, sometimes brush-makers trim the tips of the brushes that make them unusable for professional detailed work. 

As a regular artist can’t make a lab test to assess if the hair belongs to Kolinsky Sable or not, some manufacturers, especially in China, use partially or fully red sable hair and sell it as Kolinsky. A lot of Kolinsky brushes from Amazon or Ali Express that are made in China are suitable for student-grade painting or varnishing details only.

Borciani e Bonazzi Kolinsky imitation brushesKolinsky Imitation Brushes

Kolinsky imitation brushes got very popular for their wide possibilities. Watercolour, oil, acrylic, gouache – they technically can be used for all the mediums. Of course, these brushes have their limitations in the techniques applied but they still, count as the most universal brushes. 

Most manufacturers have them coloured as natural hair with a transition from rusty orange at the ferrule to dark brown at the tip. Most of the hair is not quite perforated, which makes these brushes work better for opaque and heavy-bodied mediums, such as gouache, acrylic and oil.

From our shop, kolinsky imitation brushes that are really very close by their properties to the natural hair belong to the Il Perfetto series by Italian manufacturer Borciani e Bonazzi. The filament is micro-perforated which is of of the key characteristics of natural hair brushes. 

Orange Synthetic Brushes

Paintbrushes with orange synthetic filament may have different names and belong to the most accessible and least expensive brushes. The hair itself in 95%+ of cases is made of nylon in China. 

And pricing here is quite ridiculous as technically the same brush can be sold under different brand names (with just a few variations), and the price for the same brush may vary from 50 cents to 10 dollars, for example. Most dollar-store brushes are made from this kind of fibre. 

As the fibre is made of nylon, the bundle separates and splits when you work in oil and after just a few uses it loses its shape, making it non-workable on any even slightly-detailed painting. Things get worse if you use solvents for cleaning your brushes.

For acrylics, these brushes last longer, but still, they may split just after several uses. For lighter-in-body mediums, such as watercolour or gouache, the fibre keeps its shape much better. However, the application and brushstroke possibilities here are very limited as the fibre is not perforated and releases the paint unevenly.  

These brushes are my least favourite, and I’m using them mostly for acrylic varnishing, and KOLOS Synthetic Wide Flat Brush by Rosa, for example, work perfectly for that goal.

This doesn’t mean that you should avoid orange synthetic brushes, they still have good benefits for the price paid.

Also, not ALL orange-coloured synthetic is like that. There are still some manufacturers that sell high-quality brushes with professional-quality orange synthetic, such as Borciani e Bonazzi Top Graphic Preciso 605, Borciani e Bonazzi Synthetic Triangular, Roubloff Premium Synthetic Brushes and some others. 

Mongoose Imitation Brushes

Since mongooses are endogenous species, their hair is not used in brush industry; it’s simply illegal (and inhumane). However, we have a lot of brushes that imitate mongoose hair. Most faux mongoose brushes, of corse, come from China and even respected European brands sell them under their own names without direct indication of place of manufacturing. 

Mongoose Imitation brushes are supposed to be stiffer than kolinsky brushes, but still soft and flexible enough to be applied for watercolours, gouache, acrylic and oil. From the selection that we carry on ArtMat, Roubloff mongoose imitation brushes from Russia are the best in their category. 

 

To be continued. 

In: Paints

When Mono-Pigment Colours Are Not Mono-Pigment

This also happens. And here we’re talking about fillers and extenders. Generally speaking, all organic pigments will have a certain amount of other components used as a base. They just need to have some particles “to stick to” and create a body of paint. This doesn’t count as a filler as a mineral base is NEEDED for such paints to exist.

However, there is no certain regulation that would place a border between the necessary and extensive use of fillers. That’s why many paints, either organic or inorganic, synthetic or natural,  potentially may contain more than just listed pigments. Common fillers include PW5 (Lithopone), PW18 (chalk), PW19 (Kaoline), PW21 (Barium Sulfate) and others.

In: Paints

Iron Oxide Red PR 101-102

After Iron Oxide Yellow (PY42-43) by the number of variations in colours, another iron oxide goes – Iron Oxide Red (PR101-102). Even though PR101 and PR102 have different indexes, both describe the same iron oxide red with the only difference: PR102 is natural and PR101 is a synthetic, or man-made one. 

PR102 is mostly manufactured by the calcination of hydrates of iron, and depending on the time and amount of calcination the colour can vary from yellow-orange and brown to violet-red. Although most PR101-102 colours are opaque, iron oxide red can show different grades of transparency, from transparent to very opaque one with very strong tinting properties.

The most common names include English Red, which is a kind of bright brick colour. The name of the colour comes from the military uniform that was officially adopted in England in 1645. Beyond the symbolic meaning, the choice of red colour had also financial reasons – red colour was the cheapest one available back then as it technically comes from mineral clays. Officer’s coats were bright red, and soldier’s coats were of rather brick colour, the same as traditional English red.

A lot of iron red colours have “Mars” as a prefix because in alchemy, the “Red Planet” Mars is standing for iron as an element. Usually, Mars colours describe transparent versions of PR101-102.

Another common name for colours from PR101-102 family is Indian red. The first recorded use of Indian red as a colour term goes back to 1792 and has absolutely nothing to do with the skin colour of Native Americans. The name derives from the red laterite soil found in India, which is composed of naturally occurring iron oxides (PR102) and has red-brown colour with a violet undertone.

Very beautiful caput mortuum colour doesn’t sound too optimistic. It comes from Latin caput mortuum meaning “death’s head”. Alchemists used this term for the ultimate remains of an alchemical process signifying something not changeable and as a result worthless to them. Caput mortuum represents a violet semi-transparent version of Iron Oxide Red. 

According to another version, caput mortuum colour refers to olden times when the colour was manufactured using ground-up pieces of mummies. Europeans began manufacturing caput mortuum back in the early 16th century. At the time, there was a thriving trade in mummified remains between Egypt and Europe. Paint manufacturers kept producing organic caput mortuum until the beginning of the 20th century when the usage of the colour dropped off due to ethical reasons. Then this colour was replaced by its synthetic cousin – Iron Oxide Red. 

In ENL Watercolours you can find many colours made with PR101-102 as mono pigment use, from bright red-orange (Ercolano red) to transparent violet (Cocoa Rosso Natural). And, of course, no mummies or zombies were used to make these colours.

In: Pigments

PBr24 Chrome Antimony Titanate

Naples yellow is a pigment named after the city of Naples in Italy. The origins of Naples yellow remain unclear, but it’s one of the oldest known pigments. We know it was used by Egyptians as far back as circa 1500 BC to add yellow colour to glass, and originally the pigment was made from lead antimoniate. The first recorded use of ‘Naples yellow’ as a color name in English was in 1738.

The lead-based Naples yellow was toxic and caused lead poisoning among workers who handled it and artists who painted with Naples yellow. So, later, to imitate Naples Yellow, this beautiful pastel yellow colour, without taking health risks, manufacturers started simply mixing titanium white (PW6) with yellow ochre pigments (PY42-43). However, this mixture doesn’t work for artists, who prefer mono-pigment colours. Not so long ago, in 1939, PBr24 Chrome Antimony Titanate was discovered, and in 1967 the production of this wonderful pigment began.

PBr24 is a light valued, yellowish to reddish brown to light golden, orange or tan. It may be slightly staining in watercolours and have fair tinting strength as it already contains some titanium white. As PBr24 is a synthetic (man-made) inorganic pigment, its light-fastness is excellent in all mediums. What about opacity, Chrome Antimony Titanate as most chromium and titanium oxide-based pigments, is quite opaque.

You can find this colour now in my ENL Watercolours. As this pigment has quite low oil absorption, it dries quite fast in oil painting and will be included in my ENL Oil paint collection this year.

No to Cobalts and Cadmiums
In: Pigments

Why We Say “NO” To Cobalts and Cadmiums

Historically, artists have issues finding pigments that would provide intense primary colours. Most mineral pigments used belonged to colours found in clays, or earth: such as ochre, umber, iron oxide, some earth green and blue-grey. However, bright yellow, red and blue were always a challenge to find. 

Because chemistry as a science wasn’t that developed yet, artists extracted transparent intense reds from plants, such as, Madder roots (Rubia tinctorium), or insects, such as dried bodies of the female cochineals. All they provided very intense different shades of red colours, but they faded quite fast, like most plant-derived colours. Also, the colours were transparent, which was perfect for glazing, but didn’t work for full coverage.

For opaque red, artists utilized vermilion extracted from mineral called cinnabar. It’s quite an old pigment used for many centuries around the globe. You still can observe it almost unchanged on Ancient Greek abd Roman wall paintings, as well as at Renaissance canvases. However, painting with it is quite toxic. Chemically speaking, it’s Mercuric Sulphide (HgS). 

In 1817, a German chemist discovered a new element, cadmium, which became the foundation for new shades of red paints. However, commercial products of cadmium started a whole century after its discovery, in 1919, when a patent was registered for the production of cadmium orange and cadmium red. It’s opaque very intense red that varies from orange to deep red.

A drawback is toxicity. “Cadmium poisoning has been reported from many parts of the world. It is one of the global health problems that affect many organs and in some cases it can cause deaths annually. Long-term exposure to cadmium through air, water, soil, and food leads to cancer and organ system toxicity such as skeletal, urinary, reproductive, cardiovascular, central and peripheral nervous, and respiratory systems.” (Rafati Rahimzadeh M, Rafati Rahimzadeh M, Kazemi S, Moghadamnia AA. Cadmium toxicity and treatment: An update. Caspian J Intern Med. 2017 Summer;8(3):135-145. doi: 10.22088/cjim.8.3.135. PMID: 28932363; PMCID: PMC5596182.).

Cadmiums are especially toxic in pastels, when you inhale the dust, and in watercolours, gouache or acrylic, when soiled water goes directly to water drainage and soil. And this is a question not personal safety only, but also environment.

For blue colours artists were using minerals such as lapis lazuli, apatite etc. Ultramarine colour made by grinding lapis lazuli into a powder, was one of the most expensive pigments. The name ‘ultramarine’ literally means ‘beyond the sea’, because the pigment was imported into Europe from mines in Afghanistan by Italian traders during the 14th and 15th centuries. 

In his fresco painting, Leonardo was reusing this precious pigment many times. Fresco painting implies applying colours on top wet plaster without any binder, as this plaster serves as a binder between pigment particles. After painting, Leonardo carefully drained water from a cup, where he washed his brush after ultramarine use. As particles were very heavy (they are, technically, just very fine sand pieces of a rock), the pigment saddled down and was reused.

Apart from Lapis, artists used other kinds of blue. Mayan blue comes from heated clay, which was quite light fast due to its mineral origins. Famous indigo blue is derived from Indigofera tinctoria plant. 

Smalt, a pigment made from cobalt blue glass, has been known at least since the Middle Ages. However, the isolation of the blue colour of smalt was discovered in the first half of the eighteenth century by the Swedish chemist Brandt. In 1777, Gahn and Wenzel found cobalt aluminate during research on cobalt compounds, and cobalt industrial production started in early 1800’s. 

Cobalt refers to mild toxic pigments. The most worrisome form of cobalt poisoning occurs when you breathe it into your lungs. So, definitely, not recommended for pastelists, airbrush use and fresco painting. When used in watercolours, acrylic or oil, usually cobalt is not a big concern. 

To me, cobalt extracting IS a concern. Although cobalt is mined in several countries,  the Congo is by far the largest producer. More than half of the world’s cobalt resources are located in the Democratic Republic of Congo, and over 70% of the world’s cobalt mining occurs there, and child labour is involved.

“Of the 255,000 Congolese mining for cobalt, 40,000 are children, some as young as six years. Much of the work is informal small-scale mining in which laborers earn less than $2 per day while using their own tools, primarily their hands.” (The the Wilson Center, The DRC Mining Industry: Child Labor and Formalization of Small-Scale Mining, By Michele Fabiola Lawson on September 1, 2021).

In RUSART products we use no cadmiums due to their environmental impact, and we use only one kind of cobalts – cobalt turquoise, originated from France, being sure that we’re not contributing to slavery and child labour.

(c) RUSART

How to use watercolour medium
In: Practice

How To Use Watercolour Medium?

If for oil or acrylic painting we have many mediums to choose from that serve in a different way, watercolour medium sounds a little bit weird: why watercolour needs a medium? There is no texture to build, there is no need to increase or decrease drying time? Why do I need medium for watercolours?

In fact, most watercolorists paint without any mediums added. However, there are some situations when medium helps us improve painting performance.

What is watercolour medium?

Generally speaking, watercolour medium has arabic gum as a main component. Traditionally, all watercolours had arabic gum as a binder. However, with time in mass production arabic gums was partially replaced with other sugar-based ingredients (such as dextrin) to reduce costs.

Arabic gum is a natural sap from certain kinds of Acacia trees. It’s used a lot in baking and RUSART, for example, buys food-grade arabic gum from grocery vendors to make sure high safety standards. Bakers add arabic gum to icings, chewing gums, fillings etc. as it acts as stabilizer preventing sugar from crystallizing, as well as emulsifier, providing even and smooth consistency of products.

For artist’s purposes, we use arabic gum solution with some additives. For our RUSART Naturals watercolour medium we use a small amount of honey and glycerin as plasticizers and essential oils as preservatives. 

We performed a few tests  with RUSART Naturals watercolour medium and, now, sharing the results with you.

Watercolour medium separates painting zones

 We applied watered down watercolour medium first on one half of the paper sheet and let it dry. Then we applied paint in wet technique on bare paper and on top of medium applied.

As you can see, watercolour medium prevents paint from bleeding, creating quite obvious borders between the colours.

Why? Arabic gum works like glue and holding agent, not for watercolours only. For example, for hot enamelling techniques, when artists spread glass powder on metal surfaces, they use arabic gum based holding agent, if they desire to affix enamel to certain areas.

Watercolour medium helps with washing out lines

We gave experimental pieces sometime to dry and then we used just water and squirrel imitation brush to wash out paint.

Paint came off effortlessly from the paper WITH medium, leaving behind completely white lines. Without medium paint didn’t come off in full. 

Why? Watercolour medium created a fine film between paints and paper that prevent paints from being absorbed by cotton fibre. SO, if you’re planning to correct your painting a lot, or you’re working with synthetic organic pigments (hanza yellow, naphthol red, pyrrole red, Phthalo blue or green etc.) use watercolour medium to be able to correct your lines after application. All synthetic organic pigments have stronger staining properties than mineral pigments. 

Mineral pigments don’t show that dramatic difference. Also, if your paper contains less cotton, watercolour medium’s effect will be less intense.

Watercolour medium makes some colours look brighter

As you see from the picture, colours at the top half look more intense than at the lower part of the paper. Also, you can notice beautiful flow patterns that medium helps create. However, there is a reverse side of that. Excessive use of arabic gum leaves shine and slightly tacky finish.

Why? Arabic gum is technically sap, and medium made with this gum can be considered as water-based varnish, that changes optical properties of the painting layer.

Watercolour medium helps covering oily surface 

Watercolours are water-based and grease or oil on paper surface repel watercolours. Do you remember kindergarten experiments with painting in watercolours on top of lines made with wax/oil crayons? 

Unfortunately, when we touch paper with hands, some grease from finger tips can stay on paper and affect painting outcome in unexpected way.

Arabic gum helps make your work smoother. We made an experiment. First, we drew some lines and smudged them with soft pastel. And even soft pastels can contain oils or waxes. Then we used watercolour medium and spread pastel powder with a brush. Left side doesn’t have any medium applied, and you can see that spreading is not that smooth, as well as some oily spots show off.

The right side looks softer and has no visible oil stains.

Why? Arabic gum here works as the finest film, covering oil and everything else, taking only smallest particles into the layer.

 

Make your own experiments and open new opportunities with arabic gum medium! But use it wisely. As you see, it may have some “side effects”.

(c) RUSART

How to use tinting pastes
In: Practice

How to use tinting pastes?

Tinting pastes have very wide range of use and will bring more ideas to creative artists. However, there are only few artists who ever tried them. Here we’ll try to break barriers between creativity and tints.

What are tinting pastes?

Tinting pastes are technically water-based colour concentrates. ‘Water-based’ means they can me used with any water-based paints and mediums: acrylic, watercolour, gouache, plaster, concrete, alcohol ink, PVAc tempera, gesso, acrylic textured pastes, latex paint etc. This also means DO NOT use with oil-based paints and mediums, they are not going to work.

‘Colour concentrates’ means it has pigment or dye (for RUSART Deco tints we offer pigment-based pastes only) dissolved or suspended in water. To keep this solution and mixture  even and prevent from mold growth, tinting pastes also include organic acids (CH-based), pH-neutralizing agent and preservatives. 

Ways to use tinting pastes

There are many ways how to use them. 

  1. Adding colour into a primer for pastel. So, you can make your own colour and texture with less money spent.
  2. Adding colour into a primer, gesso or textured pastes for acrylic painting. It’s less expensive and creating surface with paints and it’s also creates soft underpainting.
  3. Adding some new colours into alcohol inks.
  4. Tinting your concrete, plaster or clay for your creative projects, such as sculptures, moldings, pottery etc. 
  5. Add some colour into epoxy resin creations.
  6. Enhancing gouache, acrylic paints, or watercolours.
  7. Dying textile.
  8. Painting on plaster, like in fresco techniques.

The list can be longer and longer and it’s limited just your imagination and creativity. 

Some tips

There are some tricks on how to make your experiences with tints more predictable and enjoyable.

  1. Mix desired colour from concentrate BEFORE applying to your medium and try promotions in a small amount first. Colours have different staining properties as well as different opacity and strength. As always, yellow colours tend to be weaker than blues or greens.
  2. Mix your colour thoroughly before adding it into a medium, so your colour will be even.
  3. Cement, gesso, gouache, plaster contain chalk and/or other components that affect the resulting colour. They work as white paint in mixing, so test the colour first.
  4. Work in well-ventilated area. Even though VOC is quite low for tinting pastes, they contain acids and may cause some irritation or allergic reactions. Normally, if you’re not sensitive to ordinary acrylic paints, you’ll be fine with the tints. They have the same components as preservatives and stabilizers.
  5. If you use gesso, plaster, gouache, cement as a medium for tints, after drying colour may look lighter than in a wet form due to chalk that those mediums contain. Tinting pastes don’t contain chalk.
  6. Tints are very concentrated and a bottle can last quite long.

Enjoy your creative time!

Why watercolours fade
In: Paints

Why watercolours fade after drying?

Watercolours are very enjoyable, but right after drying results may not be what you expected: colours changed, faded and become pastel-looking. Why does it happen?

Excessive paint fillers

In a modern world we buy paints at stores and unfortunately we can’t be sure about what’s inside. To increase profits, some manufacturers excessively use fillers. For example, ultramarine may include a lot of clay, yellow colours – chalk, red colours barium sulphate. When water evaporates, chalk layer shows up and instead of vibrant colours we see pastel tones.

For some pigments mineral base may be necessary. Synthetic organic pigments, such as pyrrole red (PR254), Phthalo blue (PB15), Phthalo Green (PG7), as well as bismuth yellos and many others will need a base to show their brightness in full. Like pyrrole red (PR254) without any base will look transparent ruby, Benzimidazolone Yellow (PY154) will not cover paper evenly without a mineral base. So, sometimes, calcium carbonate (PW18), kaolin (PW19) or  Barium Sulfate (PW21) are really good to have, but excessive amounts of these ingredients lead to colour fading after drying. Watercolours in pans tend to have more of them as fillers and extenders, while watercolours in tubes normally contain more glycerine and preservatives.

Chalk in paper

Watercolorists usually prefer cold press, acid-free, 300 by weight cotton paper. These characteristics provide more controllable painting. However, that’s not everything that we need to know. Paper, that we’re buying for watercolour is white. It may be brilliant white or kind of ivory, but anyways – white. This means that fiber was coloured and bleached. Normally, for paper coloration manufacturers use titanium white as the most stable and popular white pigment, but they may add chalk and other components listed above (PW18, PW19, PW21 etc.) that show off through paint layer and cause fading.

Lack of arabic gum

Historically, watercolour binder was arabic gum. It’s a natural sap from acacia trees growing from Senegal on the west coast of Africa all the way to Pakistan and India. Its sap dissolves in water and turns into slightly amber coloured solution, which works as a glue for pigment particles. However, arabic gum is quite expensive and requires some stages of purifying, heating etc. to be used as a binder. As it’s considered to be polysaccharides manufacturers replace arabic gum with dextrine (kind of sugar). Most manufactures claiming that paints have arabic gum as a binder in fact use more dextrine than the gum. 

Dextrine indeed works very well as a glue and creates good adhesion between particles, but it has very poor spreading properties. As a result, watercolours lose their natural gloss and shine and turn into matte and pastel looking surface. 

By adding arabic gum watercolour medium you can improve paint performance.

(c) Rusart

Characteristics of Watercolour Paints
In: News

Characteristics of Watercolour Paints

Watercolour is one of the oldest but still innovative painting medium with a lot of characteristics. These glue-based paints still have more interesting to offer, while techniques and results vary from light and translucent washes to very intense and deep lines. As watercolours offer working with transparency of layer, texture of paper, paper composition, softness of a brush used, for more predictable results watercolour paints have many parameters that may or may not be listed on a tube or pan. And with more new pigments appear on the market in manufacturers’ disposal new parameters arise.

  1. Transparency
  2. Light fastness
  3. Granulation
  4. Staining
  5. Stability

We will talk about each parameter separately in other articles; here we will cover just general meaning.

Transparency

The same pigment depending on pigment grit, place and method of extraction as well as additives and fillers used. Transparency shows how much the colour is capable to cover the previous layer of paint. The more transparent the colour the less intense it covers.

Lightfastness

This term now is gradually being replaced with weather resistance as not only the light cause fading and other changes in colours. Mostly, we pursue colours with high lightfastness as neither artists to collectors like to see paintings faded.

Granulation

If the first two characteristics refer to all paining mediums, granulation, staining and stability belong mostly exclusively to watercolours. Granulation is a process in appearance when little particles of pigment show visible grains. Some people like granulation while the others avoid. Granulation is neither good or bad, just a property of a paint. Granulations looks amazingly in washes, but may be not that predictable in mixing colours.

Staining

Natural mineral pigments, such as ochres, siennas, umbers, cobalts etc, belong to true pigment “category”, when pigment and binder make mixtures that can be completely washed out and removed with water. However most modern pigments, especially organic ones, work mostly like dyes. They don’t make a homogenous mixture with binder. Instead, they colour something (another pigment, paper, plaster etc.). Such pigments can be staining, especially if the paper is very absorbent, like pure cotton. When you make a line it not always can be washed in full as paper gets coloured.

Stability

This refers mostly to property of keeping the colour in mixtures as well as showing uniformed colour while painted. For example, some pigments mixed together do not make even colour. This is fair especially when we mix mineral pigment with organic synthetic ones, Then the resulting colour may not be stable, however it doesn’t mean it will fade with time as it can have highest lightfastness. At the same time some mineral pigments made from natural stones (labradorite, malachite, lapis lazuli, serpentine etc.) even without any mixing with other colours may show unexpected shades depending on amount of water and medium used.

How to Clean Brushes from oil paints
In: Practice

How to Clean Brushes From Oil Painting?

Here we’ve collected many ways how to clean brushes after oil painting and prolong their life.

What artists really don’t like about oil painting is that it’s messy. Cleaning brushes, maintaining workspace neat takes much more efforts than when you work with watercolours or acrylics.

Rinsing in turpentine or white spirit, or mixture of both

Turpentine and white spirit are  quite different, when we’re talking about painting. However, when it’s about brush cleaning, we can treat them as the same substances. Technically, they just break up oil and that’s how your brush comes out clean and neat. As both turpentine or white spirit are toxic, never pour liquid into toilet bowl or sink. Recycle properly, when possible. If special disposal or recycling is not available, just pour liquid into a jar, fill it with paper towels or cloth enough to absorb most of the content, close your jar tightly and dispose.

Pro’s:

  • easy to get and use
  • cheap
  • can be used during painting process, as well as for final brush cleaning after use

Con’s:

  • very toxic
  • can be smelly
  • requires special disposal
  • can damage delicate hair (kolinsky or other soft hair)

Rinsing in vegetable oil

If you’re lazy and paint frequently, you can use just regular vegetable oil for cleaning your brushes. Fill a glass jar with with 2 inches of oil and simply rinse your brushes there. Remove paint residue with paper towel. To prevent brushes from hardening, keep your brushes immersed in oil until the next use. Oil can be reused as paint will simply settle down on the bottom of the jar. Make sure that your brushes are suspended and don’t touch the bottom of the jar with oil to prevent brush damage.

Pro’s:

  • easy to get and use
  • cheap
  • can be used during painting process, as well as for final brush cleaning after use
  • non-toxic

Con’s:

  • doesn’t clean your brush in full, so you should keep your brush soaked in oil all the time

Rinsing in vegetable oil and freezing

If you’re planning to make a long break between oil painting, or don’t want to keep your paintbrushes soaked in oil all the time, after rinsing your brushes in oil you can wrap them with a plastic bag and place in a freezer. 

Pro’s:

  • easy to get and use
  • cheap
  • can be used during painting process, as well as for final brush cleaning after use
  • non-toxic

Con’s:

  • doesn’t clean your brush in full, so you should keep an eye on your brushes

Cleaning with dish soap

As dish soap is a good degreaser, you can simple wash your brushes in it. After full cleaning, leave your brushes horizontally to dry completely before the next use.

Pro’s:

  • easy to get and use
  • cheap
  • non-toxic

Con’s:

  • can be used only after painting session
  • requires long time for full drying before the next use
  • doesn’t work for delicate brushes (kolinsky etc.)

Dry cleaning with paper towels

Some artists use just paper towels and wipe the brushes until they get completely dry and paint removed.

Pro’s:

  • non-toxic
  • can be used during painting process, as well as for final brush cleaning after use

Con’s:

  • requires a lot of paper towels, so this method is not environment friendly
  • doesn’t work for delicate brushes

 Different  manufactured brush cleansers

Please refer to their instructions for pro’s and con’s.

RUSART Naturals Oil Brush Cleanser

If you really care about your brushes, try RUSART Naturals this easy-to-use cleanser for oil paint brushes. This all natural medium cleans your oil brushes in seconds and keeps them soft, flexible, as if they are brand new. It’s a cleanser and conditioner at the same time.

How to use Rusart Naturals Oil-Based Brush Cleanser:

  • Wipe paint residue from your brush with a paper towel or cloth
  • Shake a jar well before every use
  • Wash your brush in this solution for 5-10 seconds or until clean
  • Remove product leftovers with a paper towel or cloth

The solution can be reasonably reused even if looks soiled. Don’t forget to shake a jar before every use.

Pro’s:

  • non-toxic
  • cleans in seconds
  • works even for delicate brushes
  • brushes can be stored for a long time after use

Con’s:

  • price
  • intended to use after work, not as a cleanser during painting.

(c) RUSART

Yellow Ochre Pigment
In: Pigments

Pigment guide: Yellow Ochre

Yellow Ochre is the second popular pigment in use for paints after titanium white. Ochres are one of the most ancient pigments used even in cave-paintings. Chemically speaking, yellow ochre is naturally or synthetically hydrated iron oxide. As most mineral pigments, yellow ochre has excellent lightfastness and varies in transparency from very transparent (like yellow mars or travertine) to opaque.

Technical Data on Yellow Ochre

With colour index 77492 pigment formula varies, depending on method of manufacturing and treatment. PY42 stays for synthetic oxide, while PY43 is natural. Natural iron oxides include a combination of one or more ferrous or ferric oxides, and impurities, such as manganese, clay, or organics.

Normally, they are used together in paint-making. When heated this pigment changes its colours to red shades and gradually transforms to PR101 pigment that also belongs to iron oxide family.

Due to wide range of usage yellow ochre can show colours from neutral yellow through orange to brick red and blackcurrant.
PY42-43 is one of the most comfortable pigments to work with as they provide excellent mixing and grinding properties in all binders: oil, acrylic, watercolours, gouache, egg tempera, PVAc etc.

Oil absorption ratio varies from 15 to 30 g per 100g, which makes this colour perfect to work with: it’s drying neither too fast nor too slowly.

Although yellow ochre can be found in many places, the most common quality sources of these pigments is France, Italy and Cyprus. What about safety, when in paints PY42-43 is not toxic at all, but dust can contain small amounts of heavy metals, manganese, lead or other minerals. So, when you work in pastels or raw pigment avoid dust and use protective gears.

Different Names of Yellow Ochre

Paints made with this pigment may have many different names as hues and transparency varies.
Here are some of the most common names:

  • Yellow Ochre (Light, Pale, Deep etc.)
  • Golden Ochre
  • Indian Yellow Transparent (hue)
  • Mars Yellow
  • Iron Oxide Yellow
  • Light Ochre
  • Mars Orange
  • Orange Oxide
  • Raw Sienna
  • Natural Yellow
  • Natural Sienna
  • Mars Yellow Orange
  • Brown Ochre
  • Natural Ochre

(c) RUSART

How to choose right canvas
In: Practice

How to choose right canvas for your goals – Part I (Canvas)

When you paint on canvas, the canvas itself is the first thing to take care of. There is no one best canvas for all the goals as all they have different properties and price, but you can always choose something that fits your goals and budget. 

First of all, canvas itself as a fabric. Here we have different options: linen, cotton, polyester and different blends.

Choice here is not straight forward, as always, but generally speaking, the thicker the fabric the more weight it can hold, meaning the more paint and medium you can apply without risk of deformation.

Polyester canvas – when to use?

Polyester or cotton-polyester blends are the cheapest options that you can find even in dollar stores. They are very thin and usually have bigger gaps between threads leading in quality loss. Polyester is technically plastic and can’t absorb anything, meaning sizing and primer may not get a proper binding with the fabric. On top of that this canvas is usually very fragile and rips off easily. So, this kind of canvas is a good choice for children’s paintings, playing with paints or doing exercises and practicing some fast techniques. This kind of canvas is not working for any painting that you want to keep for a longer time.

Cotton or linen canvas?

Cotton and linen canvasses normally is a good choice for professional paintings, provided canvas is thick and properly treated before and after stretching. We’ll talk about that in separate topics. Generally speaking, we’re looking for thick canvas preferably with double thread. That’s something you can check on the back of the canvas (see the pic.).

Double-thread canvas is kind of weaving where one or two threads are doubled. For painting the best option when longitudinal thread is thick and single and weft thread is thin and double. This kind of weaving provides the strongest support, is thick and have smallest gaps between the threads. 

Normally linen canvas is thicker than cotton one, and that’s why more expensive. Not all artists can afford painting on linen. But it’s also not always necessary.

If you’re painting in layering techniques and not using heavy paints, a proper-quality cotton canvas is a very good choice. However, for heavy impasto painting linen canvas will provide a better solution as it’s stronger and more durable.

How to choose right canvasFine grained or coarse grained canvas?

There is no one universal recipe here either. Choice of texture depends on your techniques. If you’re working in fine layering and glazing techniques, the smoother the surface the better. Especially that’s very important for portrait painting. So, fine grain and even extra priming would be the right option here.  

For impasto techniques as well as working the involves different pastes, and textures as well as for palette knife painting coarser surface will fit better. The smooth finish is incapable to hold a large amount of paint.

Although, many mediums now can be applied on canvas, we’ll take a closer look at acrylic and oil paint application as the most traditional ones nowadays.

Choosing canvas for acrylic painting

Acrylic paint is quite universal and easy-going, so most of the canvas will work well for acrylic. Choose the material, finish, size and priming that fits your goals for this or that particular painting and enjoy your creative process. Acrylic forms one non-separable layer with primer on canvas, which makes painting process seamless.

Choosing canvas for oil painting

Oil is the most complex medium and requires more skills, knowledge and experience. Here the way how the canvas was treated and primed matters a lot. We’ll have a separate article on this matter too, but for now let’s assume that the canvas is well sized and primed.

Here we have two different kinds of primers that can be used: acrylic or oil. Acrylic primer is universal and can be used for both acrylic and oil. However, to create a better binding with canvas and to prolong the life of finished oil painting (increase time of polymerization) in this case we’d suggest to start the first layer with underpainting that will create a shield between canvas and your actual paintwork.

Acrylic primer normally contains a lot of chalk inside, which is very porous and “drains” oil from painting layer. To prevent this we should create a layer that links acrylic and oil. It should be a painting layer containing  gums inside, that “seals” the pores and crates the perfect adhesion for oil paints.

However, based on my experience, the best primer for oil paints is oil primer. As oil priming doesn’t work for acrylic and also takes much longer time for canvas preparation at manufacturers’ side, less and less of them offer this option. Oil primed canvas has a lot of misuse that also forces manufacturers stop making them.

Oil primed canvas should be treated as an oil painting that is standing alone for a long time. That means if you choose oil primed canvas, treat it with retouching medium first for a proper adhesion.

That’s a very basic information regarding choosing canvas for your painting. In Part II we’ll pay attention to other aspects of canvas, such as support for it. You’ll get answers on the following questions: What is the difference in use of stretched canvas and canvas on board? How do proper stretchers look like?

(c) RUSART

Why oil paints separate
In: Paints

Why oil paints separate?

Most oil paints separate and there are many reasons for that, good and not really. There are few myths around it, that I (Elena Nahum Leroy) am going to start with. I’m working with oil paints as an artist, tester, seller and manufacturer, so I have a good chance to get full oil paints experience from different sides.

Myths about oil paint separation

Myth: Oil paints separate because they are old

Truth: Separation in some oil paints can start as soon as in a few days after they are made. 

 

Myth: Oil paints separate because pigment is heavy and it sinks to the bottom of the tubes

Truth: It’s partially true. Some mineral pigments such as titanium dioxide, cobalts etc. are really heavy and it’s a challenge to keep them “floating” in the oil without “sinking”. However, in a modern paint technologies a lot of pigments are manufactured and in fact much lighter than oil and separation still happens there. 

And now, real reasons…

 

Oil paint separation from deep inside

Oil is a quite complicated medium. I’d say it’s the most sophisticated art medium that I’ve ever used and tried. Apart from most of other mediums, painting in oil requires knowledge of chemistry and painting technologies to succeed. History knows so many examples of oil paintings made even by great and famous artists that were ruined with time because of wrong application. We’ll talk about that too, in other articles. Now, back to the point.

Generally speaking, oil paints have binder (oil), pigments (natural or synthetic), most likely will have fillers, and may have gums, solvent, beeswax or other additives. And separation can be caused by reaction between any of these components. So, even at this point it’s clear that everything is much more complicated than it seemed before. We’ll cover just most common (not all) reasons for separation in oil paints.

Wrong pigment/binder proportion

If you mix pigment with oil that wouldn’t be enough to create good oil paints, because the pigment is not connected to oil yet. We need to apply pressure and physically bind pigment and oil together with a muller (hand-processed) or a roller machine (industrial method). Some pigments require 5 or even 8 cycles to bind with oil properly. And here we have the first reason of separation.

Different pigments have different oil absorption rate. For example, titanium white takes up to 30 g of oil for every 100 g of pigment, while pyrrole red absorbs up to 70 g for every 100 g of pigment. That’s their normal absorption rates. 

However, even the same pigment may have different grit for a reason (read about that in our special topics). And finer pigments require more oil to fill gaps between finer particles to create proper binding and make paints look and feel smooth and even. But absorption rate remains the same, it’s chemistry. So, in fact we have to add more oil than needed and then we have to remove this extra oil. Else, extra oil will separate from the paint with time.

Why oil paints separatePoor grinding

Another very common reason for oil separation is poor grinding. Different pigments require different number of grinding and milling cycles and even if oil-to-pigment proportion is observed well, insufficient time of grinding may cause quite fast separation.

Weight of pigments

Some pigments are much heavier than oil. These include titanium dioxide, cadmiums, cobalts and some mineral pigments extracted from semi-precious stones, such as lapis lazuli or amethyst. With no fillers added they will separate naturally and this doesn’t mean the paints are bad. However, to create a better look, these pigments will be most likely “diluted” with fillers to create smoother consistency that, when properly done, will technically prevent separation.

Why oil paints separateFillers

However ,the leadership in separation causes belongs to fillers. Oil naturally makes colours look brighter that creates a temptation to add a paste, colour it and sell as a tube of oil paints. This temptation goes stronger, when legislation doesn’t  to disclose the full list of ingredients. As a result, some paints (student grade) have just 3-5% pigment load, for example. 

Barium Sulfate is most popular filler for oil paints due to its low cost and physical properties. First of all, it’s very heavy, which makes it the perfect adulterant for oil paints. Due to its weight Barium Sulfate make tubes feel heavier simulating a high pigment load. Also, its oil absorption rate is just 11, meaning for 100g of the powder we’ll need just 11 g of oil to create a good mixture. So, added to synthetic pigments Barium Sulfate will take extra oil and make oil paints look thicker, imitating higher pigment concentration. That’s another thing that buyers love – thick paints.

However, this trick also have a flip side. Barium Sulfate is very heavy and settles down dragging pigment with it and causes separation. 

So, there could be many reasons why oil paints separate and separation is not always a sign of old or poorly made paints. Test paints, compare them and choose the right ones that work better for your goals. Price here is not always the main indicator.

How To Read Paint Labels
In: Paints

How To Read Paint Labels

That’s very important to know what you’re buying and some information about your paints is available on labels:

  • paint name
  • grade
  • pigment used
  • binder
  • lightfastness
  • transparency
  • safety note

Paint name

Although there are many common names for paints we used to see around, there is no standard on how to name a colour. The spectrum contains millions of colours and all they can be named differently. 

Some manufacturers use traditional and most common names, such as cadmium red medium, cobalt blue, ultramarine blue etc. These names stand for pigments used and it’s easy to understand what is inside the tube.

Some names can be unique due to marketing goals or multiple pigment used. For example, Australian Grey or Australian Leaf Light by Art Spectrum or Portland Grays by Gamblin or Raw Umber Leningrad by Nevskaya Palitra. 

Also, the same pigment treated differently can provide a wide verity of hues, shades and transparency level. One of champions in that is PY42 Iron Oxide Yellow ,which has about 100 different names.

Paint grade

Paint grade is also a very questionable category as there is no standards of marking paints student or artist grade. For RUSART, we split paints into 4 categories: children, student, artist and professional. Most manufactures offer 2 categories: student and artist grade.

The main difference in paint grading is pigment load, quality of pigments used as well as fillers and mediums added.

  1. Children grade. We have a special article about art supplies for children. Generally speaking, the main criterium here is safety. Pigments used here are non-toxic and must have certain certification and labelling. Normally we talk about watercolours here and they contain a lot of dextrin (sugar) and starch instead of more expensive components.
  2. Student grade. Safety is not the main criteria here. Usually these paints lower budget for everyday use and practice. Pigment load normally lays between 3 and 20%. All the rest are fillers and binders. Cobalts and cadmiums are normally hues here, which means not real. Although professional artists prefer to use higher quality brands, student paints are still very helpful for underpainting and sketching due to there lower price.
  3. Artist and professional grade. That’s the main target for professional artists. Binders and pigment load vary, but most paints still contain fillers. If earlier information on pigment load was available in safety data sheets, for now it’s hard to find real numbers. According to our experience, pigment load in artist grade paints is between 15-70%. We will talk about pigment load in a special article.

Pigment used

One of the most important information for colour choice. Paint tube will indicate colour index (CI) that stands for chemical characteristics of pigment used. CI will start with N or P. ’N’ stands for ‘Natural’ and ‘P’ stands for ‘Pigment’. Then a colour identification comes: 

  • Y – Yellow
  • W – White
  • B – Blue
  • Br – Brown
  • Bl – Black
  • R – Red
  • V – violet
  • G – green
  • O – Orange

Index doesn’t show exactly the colour or a colour wheel. For example, PR101 is rather red-brown than bright red or PY42 is ochre but still refers to yellow colours.

Then index itself comes. It’s just a number. You can check pigment index names and their technical characteristics here >>

Transparency

This normally has 3 categories: transparent, semi-transparent and opaque. Usually manufacturers include a symbol – a square. If the square is empty the paint is transparent, if it’s half-filled – semitransparent and if the square is black the paint refers to opaque category.

Lightfastness

Nowadays that term is getting replaced with weather resistance, meaning how much paint will change its colours with time under different conditions: exposure to light, UV, moisture, temperature etc.

Safety note

Working with some pigments may involve some risks. For example, cadmiums and cobalts are known to contribute into cancer development. Emerald green (PG21) is extremely toxic and poisonous. Once used as a rat poison and to preserve wood. It was called a trendy color that killed many in victorian society. 

Some other pigments, such as zinc white, can be harmful for environment and are not supposed to be disposed into water or soil. Paints intended for sale in the USA should have safety warning for such pigments. In Canada paints may or may not contain such warnings.

And some other things that you should keep in mind:

  1. Not all ingredients used in paints will be on the label
  2. Term ‘acrylic emulsion’ or ‘acrylic dispersion’ combines many chemical ingredients, including ammonia and solvents and these ingredients will not be listed separately
  3. Oil paints may contain lead or barium sulphate fillers that will not be shown on the labels either
  4. Manufacturing date is normally absent on paint labels

As you can see, labels can give a lot of information on what’s inside. However, some very important things can be still omitted.

In: News

Watercolours – What’s Inside?

Watercolour paints have much longer history than oil and, of course, acrylics. It appeared in China in the 2nd century AD, when paper was invented, because no paper no watercolour painting.

As any paint watercolours consist of pigment, binders and other ingredients. Let’s take a closer look at them.

Pigments for watercolours

Although pigments are kind of universal for many kinds of paints, not all of them work well for watercolours. 

Normally, mineral pigments bind well with Arabic gum (watercolour binder), but most synthetic pigments require special attention. Synthetic pigments, such as phthalo blue and green, naphthols,  quinacridones, hanza, pyrrole, benzimidazolone and others tend to be finer than their mineral cousins. With water added these pigments form lumps that very hard to break into a smooth paste. That’s why manufacturers have to add more fillers and extenders to create a reliable homogeneous paste. 

Also, most synthetic pigments need a base to stick to and it’s not that easy to find information what was used as a base for a certain paint. That’s why performance may differ from brand to brand.

More information about different kinds of pigments and their use we’ll post in our News and Article section.

Watercolour Binder

Arabic gum is a traditional binder for watercolours. It’s a natural gum made from sap of certain kinds of acacia trees. Those trees are harvested in Sudan and throughout the Sahel, from Senegal to Somalia.

Arabic gum is a very safe ingredient and has a broad use in food industries. For example, bakers add it as a thickener to icing, fillings as well as to soft gums and candy. For RUSART Naturals watercolours, we buy food grade arabic gum to make sure it’s pure.

Some people think that honey is another kind of binder used for watercolours. That’s not true. Honey is a never-drying agent so watercolours based on honey will remain sticky and never form a smooth film. 

However, some manufacturers do ass honey in watercolours to keep paints moist and soft. Here we come – humectants.

Humectants and Plasticizers for Watercolours

Watercolour pains based on Arabic gum only will get dry within quite short time. They will look like a piece of chalk that’s hard to use. To keep paints soft (even for watercolours in pans), we have to add humectants, such as honey, glycerine, methyl cellulose, or corn syrup. 

These agents prevent paints from excessive dryness and increase flow. 

Preservatives

As you can see, watercolours have a lot of natural ingredients inside that in contact with water may start growing mold. Especially that’s important for watercolours in tubes, that keep moist for longer time. 

To prevent growing mold we need preservatives. Normally, manufacturers use formaldehydes or phenols to keep paints fresh. Another olden way to fight mold is using essential oils. That’s more expensive, but a safer way that we use in our RUSART watercolours.

Fillers in Watercolours

If you think that’s the least important part in the paints, you’re terribly wrong. Yes, for artists fillers is something they’d rather avoid (when possible) to keep colours clear and vibrant. However, pigments are expensive, market is competitive and only specialists or really professional artists will notice a difference. So fillers are technically the main ingredient for most student and artist grade watercolours. Professional watercolours normally have lower level of fillers.

Also, some pigments cannot been used without fillers because they don’t get the right consistence and need a base to for smooth texture. However, for most mineral pigments fillers are not necessary.

Manufactures use many chemicals as fillers. For watercolours the most common ones are dextrin (and other cheap sugars), chalk, clays, barium sulphates. Normally, these ingredients are not listed on the labels.

Oil Painting Essentials how to choose oil painting supplies
In: Practice

Oil Painting Essentials

All oil painters have their own lists of oil painting essentials for everyday work. There are many tools, mediums, brushes and many colours available so it’s very easy to get lost. Especially, for beginners. 

On top of that oil paints are quite expensive and not everyone can afford buying more supplies than really needed. Let’s see what you’ll really need to start and what can wait till a better moment. Below you can find some recommendations based on our practice and experience. It may be different from what other artists think and use as all artists are different and have heir own preferences.

Different techniques require different brands of oil paints

  1. Alla Prima. Technique implying working wet-on-wet and finishing a painting during one approach. Most impressionists and a lot of contemporary artists use this technique. For this technique you need good selection of basic colours, especially reds and yellows. Student grade colours have lower pigment load as well as may have some white inside those colours that can “melt” and provide some muddy look. Your choice should be focused on opaque paints that provide pure colours. So, you’ll need artist and professional brands of oil paints, such as (from our shop) Gamblin, Master Class, Old Holland, Dartecor, Art Spectrum and other brands.
  2. Flat technique doesn’t require too much paint to use and you can make few layers one on top another to enhance the colours. You’ll need to mix colours though, but not in big quantities. So, for underpainting casual brands (Ladoga, Rosa Gallery etc.) would work well, and for top layers – professional ones (MasterClass, Gamblin, Art Spectrum etc.). 
  3. Impasto. Here you’ll need thick paints and probably you’d be interested in saving 🙂 The thickest but still not too expensive brand is Art Spectrum. The other brand with very high viscosity is Old Holland, but it may be too pricey for bulk use. One of the options is using wax-based medium that created texture, but wax has it’s own drawbacks that will be discussed in other articles.
  4. Glazing and multi-layering. Here you need minimum fillers and maximum pigment load, so use professional brands only, such as Old Holland or Dartecor.

Different techniques require different oil colours choice

  1. Old Masters’ techniques imply a lot of glazing and working with transparent, but still intense, colours. They usually used monochrome underpainting in combination of white and earthy colours and then many glazing layers with transparent paints. That’s how their painting shine and make an impression of glass between two realities. So, here you’ll need titanium white, burnt and raw sienna, raw umber, ochres, and transparent yellows (hanza yellow, Indian yellow etc.), reds (alizarin crimson, pyrrole red etc.), blues (ultramarine and maybe some phthalo shades), greens (nicosia green, phthalo green), and earthy kids of mars. 
  2. Landscapes. Opaque colours are important here, so choose red, yellow, and orange cadmiums, oxide chromium for green, blue and turquoise cobalts, titanium white, and a variety of earthy colours. It’s also good to have good purple, such as cadmium purple, for accents and shadows.
  3. Portrait. Your choice will be pretty much the same as the Old Master’s techniques plus some opaque colours, depending on your style.
  4. Still lives and flowers. Bright and opaque colours are must have. You’ll need more kids of yellow (cadmium yellow lemon, medium and deep, Indian yellow, hanza yellow), reds (cadmium red, alizarin crimson, quinacridones), pink and magenta colours (quinacridone rose, magenta, cadmium purple), good blues (ultramarine, phthalo, cobalts), green (chromium oxide, phthalo, cobalt), and purple (ultramarine violet, cadmium purple). You’ll also need titanium white and good selection on earthy colours (yellow and golden ochre, burnt sienna, burnt or raw umber etc.). 
  5. Abstract. Here everything depends on the style, but definitely a lot of titanium white and opaque colours we discussed above.

Different techniques require different brush choice

  1. Impasto. For this technique you’ll need a brush that holds a lot of paint. Natural hog bristle brushes preferably with shorter hair for more controllable application would work the best.
  2. Glazing. Your focus will be soft brushes. Everything depends on particular technique, but most likely you’ll need to have a couple of kolinsky sable brushes in your collection. 
  3. Flat. Synthetic brushes would work best of all. Some of them are softer, while the others stiffer – choose what matches your hands. Hog bristle may be too stiff and kolinsky or squirrel may seem too soft. 

Do I need palette knife?

You may or may not use palette knives for painting, but we still recommend to have one medium size metal palette knife for mixing colours and cleaning your palette or scraping paints from your painting in case of failure.

What kind of palette to choose?

For oil painting you’ll need a flat palette. Everything else is a matter of taste: oval, rectangular, plywood, wooden, glass, plastic, wax paper or foil… Many choices are available now.

Do I need oil mediums?

You’ll definitely need painting oil (linseed or another one depending on properties you want to achieve). All other mediums are extra. Read more about different mediums in our knowledge base.

How to choose support?

We always recommend to begin with primed and stretched canvas for oil painting. However other options are always possible. We’ll explain the difference between different types of canvas and how to choose a good one in our articles.

What is a budget?

It’s possible to make a very small trial set for oil painting under $100, but if you want full size tubes and brushes that last longer, your budget for basic kit will be between $150-200. It can go higher, of course, if you buy top-quality paints and larger size of canvas. For some brands, a brush can cost you $70+ or a tube of paints – $100+ (such as Lapis Lazuli). 

(c) RUSART

water based paints and water soluble paints
In: Manufacturing

Why water-based paints are not water-based

Now we can see more and more labels saying “water-based paint” or “water-based varnish” or “water-based medium”. In fact, only few kinds of products can be truly called “water-based”. Let’s look inside “water based paints” meaning.

Why company use “water-based” for their labels?

All these comes from the times when acrylic paints started to appear on the art supplies market and when a massive campaign against oil painting began. Wherever possible acrylic paint advocates poured a bucket of dirt on oil painting manufactures claiming that oil paints are toxic, not safe, and acrylic paints are much better, because they are water-based. Then the market was roughly split into “toxic oil-based” products and “safe water-based” ones with the big lie started.

Now manufacturers have many reasons to call more and more products “water-based” because:

  • “water” means natural and “water-based” attracts customers
  • “water-based” is a clear statement and easy to understand
  • labelling paints as “water-based” is a simple way to stay apart from alcohol- and oil-based ones.

Water-based vs water-soluble paints

A true meaning of “water-base” is a mixture or solution of pigment, dye or tint in water. We use these fluids for tinting plaster, paper, gesso or primer and other mediums. You can find tints at our shop too.

Manufacturers also use pigments dissolved in water for fresco painting, where wall plaster serves as a binder. For any other cases we need a binder to “glue” pigment particles together and keep them attached to a support, such as paper, canvas, wood etc. Binder is a base for any paint. So, water based paint meaning is very narrow. And talking about “water-based” paints we should rather say “water soluble” paints.

Water soluble paints include a very wide range of products:

  • watercolours (based on Arabic gum)
  • acrylic paints (based on acrylic dispersion or emulsion )
  • Latex paints (based on acrylic resin)
  • Water-soluble ink (based on acrylic dispersion)
  • Gouache (based on Arabic gum or acrylic dispersion)
  • PVAc tempera paints (based on poly vinyl acetate)
  • Casein paints (based on casein and oil)
  • Finger paints (based on dextrin, starch and other sugar-glue binders)

As you see, a spectrum of “water-based” paints is very wide and it doesn’t always mean “water plus pigment only” pair.

Potential other ingredients for water-soluble paints

Depending on kind of paint and its intent to use paints will have some other components beyond just binder:

  • Fillers – to make a tube look bigger and replace expensive components like pigments
  • Enhancers – to make paints spread easier, enrich colours or achieve other properties, like opacity/transparency, increase viscosity, add gloss or matt finish, reduce or increase drying time and other
  • Preservatives – to prevent mold growing and extend shelf life
  • Humectants – to prevent paints from drying 

And here we can find some harmless components, such as honey, clays, marble dust, corn syrup, starches, dextrin, essential oils, resins, silica, glycerine etc. 

On top of those paints most likely will contain one or more of those: isopropyl alcohol, white spirits, solvents, ammonia, formalin, phthalates, xylene and other.

Always check list of ingredients, especially if work indoors. Manufacture safety data sheets do not disclose all information.

You can read more about different ingredients of paints and how they contribute into your art and your health in our knowledge base. And get updates to your email with our newsletter.

Non-toxic art supplies for children: safety
In: Manufacturing

Art Supplies for Children: Safety First

When we buy art supplies for children, the first thing we think about is safety. With this in mind we search for “nontoxic” labeled on art and craft supplies for children and easily find it! Let’s learn more what this label really means.

What “nontoxic art and craft supplies for children” mean?

All art supplies for children by retailers located in the USA and Canada must undergo through third party tested certification for toxicity. However, term “toxic” is limited by ingredients that cause “adverse chronic health effects” and “acute and/or chronic health hazard”. 

One of the most common organization that certifies products internationally is Art & Creative Materials Institute, Inc. (ACMI). Their certification split products into two categories:

  1. The AP (Approved Product) – art materials that are safe and that are certified by a medical expert to contain no materials in sufficient quantities to be toxic or injurious to people or to cause acute or chronic health problems..
  2. The CL (Cautionary Labeling) Seal – products that are certified to be properly labeled for any known health risks and with information on the safe and proper use of these materials. The CL seal is not allowed on any children’s materials.

Safety labels for art supplies ACMI

Everything sounds very good and if you look at AP label you can safely use it for children, of for yourself. We thought the same way before we realized some other things… We found AP label on paints (especially sets) containing cadmiums, cobalts, ammonia, formalin, ethylene glycol and other chemicals. If paints with some of these chemicals are to be sold in California, they may have special “warning” labelling. 

Where to find more information?

Normally, all art supplies should accompany with Manufacture’s Safety Data Sheets (MSDS), where composition and chemicals have to be disclosed. However, most manufacturers keep a list of ingredients secret and MSDS contain only general information, like “no hazard known”.  

For example, the biggest supplier of children art materials in North America, Crayola, doesn’t show ingredients at all. We even can’t tell what kind of pigments are there and what they use to prevent paints from growing mold. You can find MSDS here: https://www.crayola.ca/about-us/crayola-msds.aspx 

There are many reasons why manufacturers hide ingredients, from literally hiding something to just protecting themselves from competitors. RUSART finds this practice dishonest and as children may use paints and other supplies in many ways, including licking and painting on their skin, knowing a full list of components is very important.

Why knowing ingredients of paints IS important?

Nontoxic is not always nontoxic

First of all, term “toxic” is much broader than standards determine. Even ASTM D-4236, the standard practice of labeling art materials for chronic health hazards, is saying that “1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.” 

That means, even if you see a label “conformed to ASTM D-4236”, you and yourself are in charge of use of the product. That’s your responsibility if something goes wrong.

Misuse can occur

Secondly, all art and craft paints are assumed to be used properly. So, paints – for painting on paper (or other listed support), pencils – for drawing and paper etc. But what if your child accidentally ingests paints? And that’s a very common paint “misuse”.

A lot of paints for children contain dextrin and corn starch as a filler, so paints may taste yummy for them to lick. As a white colour or as a filler companies use titanium or zinc oxides. Titanium oxide is quite safe chemical (read more in our knowledge base), but zinc oxide when ingested may cause some unwanted effects.

Cadmiums and cobalts usually are not an issue for kids paints for economical reasons. These pigments are so expensive, that manufactures would never use them for children.

Hidden chemicals

Another big issue is formalin, which is a very commonly used preservative in paints. In some countries, such as EU and Russia, it’s legally prohibited to use it in paint-manufacturing. But it’s not prohibited to sell paints containing formalin. That’s why, when you buy non-toxic paints from China, no one can guarantee they have no formalin. Similar issue you can find with phthalates.

Allergies

And, what’s very important, that’s even paints come out absolutely non-toxic, they still can cause allergies. And knowing a list of ingredients helps a lot. Paints for children may contain wheat, honey, and other allergens. These ingredients are essential for natural paints but should be avoided with those who has certain allergies.

Conclusion

  • Non-toxic label doesn’t guarantee that a products is really “non-toxic”
  • Check with MSDS
  • Choose art materials that disclose lists of ingredients
  • Stay informed with RUSART Newsletter
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