The Cyanotype Process

Hello, I’m Brittny.
I’m the one who creates every terra print garment and I’m here to answer the question…
What is the cyanotype process anyway?!

Cyanotype is a four-part process. The first part of the process is sensitizing the canvas with a liquid chemical solution and the second part is exposing the sensitized canvas to ultraviolet light (SUN-RAYS). Third and fourth parts include printing and rinsing.

The sensitizing solution is made up of two powders which are mixed with water and then mixed together in equal parts. Potassium ferricyanide (a red powder) and ferric ammonium citrate (a green powder). Having too much or too little of each of these will result in varying outcomes such as lower printing speed, blue color bleeding or just simply not working at all. So using rubber gloves and scales is recommended to get the mixture just right. I like to then let the mixture sit for 24 hours in a completely light-free environment before using to sensitize my canvas.

For sensitizing the canvas and letting it dry, you need a completely dark room. Any amount of light will begin the development process and you won’t get your desired results. So, prepare accordingly before beginning.

Once the canvas is sensitized and dried it is time to lay out your design onto it and expose it to UV light. Since Cyanotype is a ‘negative process’ remember that areas where light does not hit the sensitized material will remain unprinted. Other areas will turn a light-strong blue hue. Depending on how strong the light source is or how sunny of a day you are printing in, the exposure process can take anywhere from 10 minutes to two hours. Play with different lighting and timing to get a look that you love.

Then you wash the canvas in cold running water until the green/yellow residue is gone from the non-exposed regions of the canvas. As it dries the blue will darken.

The funnest part is playing with what you can imprint onto your canvas! Anything that casts a shadow will work (e.g. feathers, tools, plants, photo negatives…), the options are endless!

Tag us @Terra_Prints on Instagram to be featured and share your cyanotype works of art!

Sources + Supplies:

Blue Prints On Fabric - local supplier and info source

Dharma Trading Co. - textile craft supplies

Cyanotypes on Fabric: A blueprint on how to produce ... blueprints! - paperback

Anna Atkins: Blue Prints - hardcover