Best Archival Brushes (2026): Soft, Dry, and Always Away From the Spine

Dry cleaning, and why water is the enemy

Paper is a mat of fibres held together by sizing. Introduce water and several things happen at once: the fibres swell and the sheet cockles, the sizing softens, water-soluble inks and dyes can move, and as it dries the water carries dissolved dirt to the edge of the damp area and leaves a hard brown tideline that is far more obvious than the dirt you started with.

So the sequence in conservation is always dry first, and often dry only.

A soft wide brush lifts loose surface dust and grit off a page without pressing it into the fibres. This sounds trivial and it is most of the job: the majority of what makes an old book look grubby is loose particulate sitting on the surface.

The direction matters. Brush away from the spine and off the outer edge, so dust leaves the book rather than collecting in the gutter where you cannot reach it. Working inward packs dirt into the fold permanently.

No pressure. Grit under a bristle becomes an abrasive. The brush should barely bend.

Work over a clean surface you can wipe down between books, or you will simply move the dirt from one to another.

Then, if dry cleaning is not enough, the next steps are still not water: a smoke sponge for soot, or a document cleaning pad for ingrained surface grime, both used gently and both tested first.

Hair, shape and testing before you touch anything

Soft natural hair is the standard because it moves dust with almost no stiffness. Goat, sheep and squirrel are the usual choices, and hake brushes — wide, flat, soft, traditionally Japanese — are the archetype for exactly this work.

Synthetic is not automatically worse but it is usually stiffer. Cheap synthetic bristles have blunt cut ends that scratch, where natural hair tapers to a fine point. Good synthetics like the squirrel imitations in the Princeton set are soft enough for the job and hold their shape better when damp.

Shape follows task.

• Wide flat for pages, boards and covers. Covers ground fast with no pressure.
• Round soft for detail, gutters, and the recesses of tooled or embossed bindings.
• Very small for lifting debris out of a tear before you repair it.

Watch the ferrule. A metal ferrule can scratch a cover if you let it touch. Some conservation brushes use no metal at all for this reason.

Then testing, which is not optional. Before any technique touches an item you care about, try it on an inconspicuous corner: the back of a rear board, the bottom edge, an area already damaged. Look for ink moving, surface lifting, or colour on the brush.

Know when to stop. Conservation ethics prioritise stability over appearance. An intact but grubby page is worth more than a clean one you damaged, and irreversible interventions are the ones to avoid. If a book is genuinely valuable, the right move is a professional conservator, not a better brush.

Beyond the brush

Handle books properly. Support the spine, do not open a tight binding flat, and never pull a book off a shelf by the headcap, which is the commonest way spines are torn.

Wash and dry your hands rather than wearing cotton gloves. Gloves reduce dexterity, snag on fragile paper and stop you feeling how a page is behaving. Clean dry hands are the conservation standard for most paper.

Store books upright and supported, or flat if oversized. Leaning puts a permanent lean into the boards.

Control the environment, since it does more than any cleaning. Stable moderate humidity, away from direct sun, and off exterior walls. Damp brings mould; dry brittleness cracks leather and paper alike.

Isolate anything mouldy immediately. Mould spreads through a shelf, and active mould is a health risk. Bag it, keep it away from everything else, and get advice before treating it.

Do not use household products. Sellotape, PVA craft glue, wood polish and leather cream all cause harm that is difficult or impossible to reverse. Book repair adhesives are chosen to be removable later, which is the whole point.

Document what you do. A note of what was done and when is standard conservation practice and it matters to whoever handles the book next.