chemistry of paint: where does paint come from?

16
What’s inside this paint? What gives paint its color?

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Chemistry of paint: Where does paint come from?Adaptable for High School or University level.Deliver this short lecture midway through an "Intro to Painting" lesson.

TRANSCRIPT

Page 1: Chemistry of paint: Where does paint come from?

What’s inside this paint?What gives paint its color?

Page 2: Chemistry of paint: Where does paint come from?

If you wanted to make your own paint, what

would you need?

Page 3: Chemistry of paint: Where does paint come from?

First, an ingredient to give the paint colour. This is called a pigment.

Page 4: Chemistry of paint: Where does paint come from?

Some pigments start as minerals or gems, and are ground into powder.

(This is true cobalt blue, which comes from an expensive gemstone in Africa. 4 oz. of cobalt powder costs $215 USD, or $250 SGD)

Page 5: Chemistry of paint: Where does paint come from?

Some pigments start as rocks or clays.

(This is burnt sienna, which comes from a certain soil in Italy. You bake it in a furnace, hence BURNT sienna, and you grind it up.)

Page 6: Chemistry of paint: Where does paint come from?

Some pigments come from ground-up plants (or even juices from animals).

(This is sap green, which comes from ripe buckthorn berries. Sap green is common, cheap, and has been around for hundreds of years.)

Page 7: Chemistry of paint: Where does paint come from?

Some pigments are made in a laboratory from chemicals. These are the newest pigments.

(This is cadmium red, which comes from a mixture of cadmium sulfide and cadmium selenium. Scientists have been making this artificial colour in labs since the 1920s.)

Page 8: Chemistry of paint: Where does paint come from?

These pigments can make oil, acrylic, or watercolor paints, but they can also

make pastels or colored pencils.

Page 9: Chemistry of paint: Where does paint come from?

Also, these pigments are never exactly red, blue, or yellow.

Instead, a pigment might be a dull reddish orange or a greyish

blue-green, or a bright blue-violet.

Page 10: Chemistry of paint: Where does paint come from?
Page 11: Chemistry of paint: Where does paint come from?

Do you recognize any of the colours here? If you start with a few, you should be able

to mix the rest.

Page 12: Chemistry of paint: Where does paint come from?

So to make paints, the first ingredient you need is a pigment.

Page 13: Chemistry of paint: Where does paint come from?

The other ingredient you need is called a binder, or vehicle.

the first ingredient you need is a pigment

Page 14: Chemistry of paint: Where does paint come from?

Linseed oil + Pigment = Oil paint

Page 15: Chemistry of paint: Where does paint come from?

Acrylic Binder + Pigment = Acrylic paint

Page 16: Chemistry of paint: Where does paint come from?

Review from last week:Do you remember the three

differences between oil and acrylic paints?