Block printing

Printing inks: what actually works on paper and what works on cloth

Most disappointing block prints are not carving problems. They are ink problems: the wrong family of ink for the surface, or the right ink rolled out far too thickly. Once you can name the five kinds of ink you are likely to meet, the choice stops being guesswork.

The five families

Water-based block-printing ink

This is what most starter sets contain, and for paper it is a reasonable default. Clean-up is water and a rag, there is nothing to ventilate, and prints are touch-dry in minutes.

That fast drying is also the main handling problem. In a warm room the ink skins over on the slab, the roller and the block while you are still positioning the paper, and a half-dried film prints patchy. Roll fresh ink for each print, and wash the block as soon as ink tacks up in the detail. A light mist of water over the slab buys a few minutes, and some ranges sell a retarder.

On fabric, plain water-based block ink is not a serious option. It sits on the surface of the fibres with nothing binding it there, so it stiffens the cloth, cracks along folds and largely disappears in the first wash.

Water-based ink with a fabric medium, or dedicated fabric block ink

This is the honest answer for textiles. Either buy an ink formulated for block printing on fabric, or mix a textile medium into a compatible water-based ink at the ratio the manufacturer states, usually between one part in four and one part in two. The medium supplies the binder that grips the fibre and stays flexible.

The step people skip is heat setting, without which the whole exercise is decorative rather than durable. Let the print dry fully first, typically overnight, then press it with a dry iron, no steam, on the reverse of the fabric, through baking parchment or a clean cotton cloth. A few minutes of steady pressing with the iron kept moving is the usual instruction, at the hottest setting the fabric will tolerate. Check the ink's directions, and leave the piece a few days before its first wash.

Oil-based relief ink

Traditional oil-based relief ink has a long open time, so it stays workable for hours and never dries on the block mid-session. It lays down dense, even blacks and holds fine detail better than anything else here. In exchange, clean-up needs white spirit, or vegetable oil followed by soap, and drying on paper happens by oxidation over two to seven days. Prints must be laid out flat and single-layer or they will offset.

Water-washable oil-based relief ink

These are oil inks with a modified vehicle, so soap and warm water lift them from tools and glass. You keep most of the open time and much of the density, and lose the solvent. Drying on paper still runs slower than water-based ink, usually a day or more.

Screen-printing acrylic fabric ink

Acrylic inks sold for screen printing on textiles can be block printed, and once cured they are the toughest option on cloth. The catch is body: many are thicker than relief inks and need thinning, or a softer roller, to roll out thinly instead of sitting in ridges. Some are heat set and some air cure over several days, so read the label.

Comparison at a glance

Rolling out: listen for the hiss

Squeeze a line of ink along one edge of a slab of glass or acrylic and work it out with the brayer, rolling one way, then across, then diagonally, lifting and turning the roller so it charges evenly all round. You are after a thin, velvety, matt film with no ridges at the roller's edges.

The ink tells you when it is ready. A correctly rolled film makes a distinctive soft hiss, almost a crackle, as the roller lifts from the slab. Too much ink is silent, and looks glossy and wet.

Thickness matters more than almost anything else you control. A thick layer squeezes down into the carved channels under pressure, so fine lines fill in, small cleared areas go solid, and every edge grows a squashed halo. If a proof looks blobby and the detail has vanished, the answer is almost never to carve deeper. It is to roll out less ink.

Paper

For a first attempt, use a smooth, lightweight paper. Relief printing transfers ink only from the raised surface, so the paper has to make contact everywhere at once. Smooth cartridge, thin printmaking papers and Japanese mulberry papers in roughly the 70 to 130 gsm range all take a burnished print cleanly.

Heavily textured watercolour paper is the usual disappointment: a rough or cold-pressed surface is peaks and valleys, the block touches only the peaks, and a hand-burnished print comes out mottled. It can be done under a press, but it is a poor place to start.

Fabric

Pre-wash and dry the fabric before printing. New cloth carries sizing that stops ink reaching the fibre, and if you print first and wash later, the finish washes out and takes part of your print with it. Skip fabric softener, then press flat.

Put a barrier inside anything with two layers. Stiff card or plastic slid inside a tote bag or a t-shirt stops ink striking through to the back panel. Tape the fabric flat so it cannot shift as the block lifts, and pad the table with newspaper or felt so the cloth meets the whole block.

Natural fibres take fabric ink best: cotton, linen and canvas are reliable. Water-repellent finishes are usually hopeless, and the low iron temperature synthetics tolerate makes proper heat setting difficult. Print a test on an offcut of the same cloth and wash it before committing to the finished piece.

If you are still choosing gouges and blocks, start with carving your first lino block. The block printing box is in development, planned around water-based inks for paper.