Historical context
Cyanotype was invented by Sir John Herschel in 1842 (see the cyanotype guide). Printing it on cloth rather than paper is a craft practice. Ruth Brown's Cyanotypes on Fabric (revised edition, 2016) is the main modern book; our sources do not date earlier textile use, so we give no inventor or year.
What it is and how it differs
- Same chemistry, different support. The sensitiser is the ordinary two-part cyanotype mixture, applied to fabric instead of paper.
- Natural fibres only. Cotton, linen and silk are "all excellent canvases" (Malin Fabbri). Synthetics such as polyester do not work because the chemicals do not stick to the fibres. A cotton and polyester blend can work, with less vibrant colour. Ruth Brown also found rayon and hemp usable, and wool problematic because of its lanolin.
- Washing is the weak point. Any washing shortens a cyanotype's life (Fabbri). A fabric print is best treated as something to hang, not to launder.
- Weave sets detail. A rough or loose weave breaks up detail; a fine, smooth weave gives sharper images (Brown).
Materials and chemistry
Ruth Brown's basic recipe is 15 g potassium ferricyanide and 30 g ferric ammonium citrate dissolved in 250 ml of warm water. The usual two-bottle formula is in the cyanotype guide; if you buy a kit, follow its instructions.
Solution needed per metre
Brown's figures are for fabric 114 cm wide:
| Fabric | Solution per metre |
|---|---|
| Silk chiffon 3.5 | 35 ml |
| Silk habotai 10 | 70 ml |
| Prima cotton, medium weight | 140 ml |
| Silk/viscose velvet, short pile | 375 ml |
Procedure
- Choose the fabric. Buy cloth "prepared for dyeing" (PFD) or wash it to remove surface treatments. Wash ready-made garments such as t-shirts before use (Brown).
- Scour silk if needed. Silk may carry sericin, which reduces absorption. Brown simmers it for 30 minutes in soda ash: 10% of the fabric's weight in soda ash, dissolved in 40 times that weight of water (100 g of silk needs 10 g soda ash in 4 litres). Rinse very thoroughly, with a splash of vinegar in the last rinse if the water is hard. Residual alkalinity can damage the print.
- Coat in dim light. Stir the chemicals first. Use a brush without a metal ferrule (a Japanese hake, pastry brush or foam brush), or dip the fabric in a tray and squeeze out the excess (Fabbri). For larger pieces, move the cloth with gloved hands so the solution does not pool in folds (Brown). Keep the damp fabric away from metal pins, which cause dark marks.
- Dry in the dark. Use a plastic line and plastic pegs, or a flat surface; gentle heat from a hair dryer or hot-air fan is acceptable (Fabbri). Brown found a domestic tumble dryer on its lowest setting took about 20 minutes for a couple of metres of medium cotton. White fabric looks greenish-yellow when dry.
- Expose. Fabbri's wash tests on 100% cotton used a 15-minute exposure; judge your own by the image, as for paper.
- Rinse. Fabbri's test pieces were rinsed for 5 minutes each.
- Oxidise and dry. Dry as for paper. The image darkens as it oxidises; if it fades, Bostick & Sullivan note that keeping a print in the dark for 2 to 4 weeks lets it re-oxidise.
Washing and aftercare
Fabbri tested four pieces of 100% cotton after a 15-minute exposure:
| Treatment | Result |
|---|---|
| Unwashed | Stayed brilliant blue and white |
| Mild hand-wash liquid (no phosphates or bleach) | Slightly bleached after one wash; noticeably bleached after 10 gentle washes |
| Powder containing bleach and phosphates | Bleached yellow after a single wash |
| Liquid soap with phosphates | Bleached yellow after a single wash |
Check labels for phosphates, bleach and sodium, test a small piece first, and expect fading. Dry cleaning may work; ironing should be quite safe (Fabbri). A bleached print can still be toned, for example in tea (see cyanotype toning). Treated but unexposed fabric has a short shelf life; store it cool, dry, dark and wrapped in light-proof material (Brown).
Troubleshooting
| Problem | Likely cause | Remedy |
|---|---|---|
| Chemicals will not hold | Synthetic or finished fabric | Use natural fibre, prepared for dyeing or washed (Fabbri, Brown) |
| Weak or patchy blue | Surface treatment or lanolin left in the cloth; uneven coating | Wash or scour first; coat evenly (Brown) |
| Image bleaches or yellows | Alkaline residue, or washing with detergent | Rinse out soda ash thoroughly; avoid phosphate and bleach products (Brown, Fabbri) |
| Spots on the print | Undissolved powdered detergent | Avoid powders (Brown) |
| Streaks | Hanging wet fabric | Lay flat or squeeze evenly (Fabbri) |
| Solution turns blue before use | UV leaking in | Coat and dry in artificial or indirect light (Brown) |
We have found no sourced method for large-scale or mural work, so we do not give one. Follow a specialist reference.
Safety
Wear gloves, a dust mask and protective clothing, and read the safety data sheet before handling the powders. Do not confuse potassium ferricyanide with potassium ferrocyanide (Brown). Never heat ferricyanide or mix it with concentrated acid, as that can release hydrogen cyanide.
| Chemical | Hazards |
|---|---|
| Ferric ammonium citrate (green or brown)Warning | Causes skin irritation.; Causes serious eye irritation. |
| Potassium ferricyanideWarning | Causes serious eye irritation.; Toxic to aquatic life with long lasting effects. |
| Sodium carbonateWarning | Causes serious eye irritation. |
| Hydrogen peroxideDanger | May cause fire or explosion; strong oxidiser.; Harmful if inhaled.; Harmful if swallowed.; Causes severe skin burns and eye damage. |
Classifications from the European Chemicals Agency (official EU classification where one exists, otherwise the one agreed by REACH registrants or most often notified). Read the safety data sheet that comes with your chemicals, and dispose of them in line with local regulations.
- Soda ash is sodium carbonate, an eye irritant (H319); take care with the hot simmer.
- Keep utensils separate from food use, and keep fabrics away from electrical items while damp (Brown).
- Hydrogen peroxide is optional; use only 3% pharmacy grade. Bostick & Sullivan's paper instructions dilute 100 ml of 3% to a litre.
- Dispose of used solutions as chemical waste; do not pour large volumes down a drain.
Further reading
Ruth Brown, Cyanotypes on Fabric (revised edition, 2016). The book-length treatment of fabric choice, coating and care.
Christina Z. Anderson, Cyanotype: The Blueprint in Contemporary Practice (Routledge, 2019). Covers alternative surfaces among its cyanotype variants.
Mike Ware, Cyanomicon. Free from mikeware.co.uk; covers the chemistry and alkali sensitivity of Prussian blue.
Sources
- Preparing the canvas: cloth, paper and natural fibre fabrics for cyanotypes, Malin Fabbri, AlternativePhotography.com
- Washing cyanotypes on fabrics or cloth, Malin Fabbri, AlternativePhotography.com
- Cyanotypes on fabric: preparing the fabric, Ruth Brown, AlternativePhotography.com
- Cyanotypes on fabric, Ruth Brown, AlternativePhotography.com
- Cyanotype Kit Instructions, Bostick & Sullivan
- ECHA CHEM substance record: Potassium ferricyanide, European Chemicals Agency (hazard classification, via the Silverlog chemicals database)
- ECHA CHEM substance record: Ammonium iron(III) citrate, European Chemicals Agency (hazard classification, via the Silverlog chemicals database)
- ECHA CHEM substance record: Sodium carbonate, European Chemicals Agency (hazard classification, via the Silverlog chemicals database)