Preserving Works on Paper

Every collector of works on paper eventually confronts the same tension: these are objects made to be looked at, and looking at them costs something. The damage light does is cumulative, irreversible, and paid for in instalments so small that nobody notices until a mount is lifted and the difference is visible.

Light

Light fades pigments, dyes and inks, yellows paper, and weakens fibres. The effect depends on intensity multiplied by time, so a work displayed at low light for many years may suffer as much as one displayed brightly for a few.

Some materials are especially vulnerable: watercolours, which include several fugitive pigments; coloured inks; chromogenic colour photographs; dyed papers; and anything already faded.

Practical measures. Never hang a work in direct sunlight, or opposite a window. Keep general light levels modest — the conventional museum figure for paper is around 50 lux, which is dimmer than most domestic rooms and a useful reference point. Use ultraviolet-filtering glazing. Avoid halogen and any lamp close to the surface; light-emitting diodes with low ultraviolet output are preferable.

Best practice is rotation: display a work for a limited period — a few months in a year is a common institutional discipline — then rest it in dark storage. A facsimile in the frame during the resting period is an entirely respectable solution.

Framing

Conservation framing is not expensive relative to what it protects.

Mount and back with acid-free, lignin-free board of conservation quality. Ordinary mount board burns a brown line into a sheet within a decade.

Hinge with Japanese tissue and wheat or rice starch paste, applied sparingly at the top edge only, so the sheet can move with humidity. Never use adhesive tape, self-adhesive corners on the sheet itself, dry mounting, or any adhesive marketed as permanent.

Keep the work off the glazing, using a window mount or a spacer. A sheet in contact with glass will eventually stick to it, particularly in humid conditions, and a photograph will ferrotype.

Seal the back with an inert barrier board, not with brown tape onto raw wood.

Ask the framer to return any old mount, backing board or label. These carry provenance.

Storage

Unframed works belong in a solander box or an archival drop-front box, flat, each in its own folder or interleaved with acid-free tissue. Do not stack them so deeply that the lower sheets bear weight, and do not store them upright in a portfolio unless each is fully supported.

Store in a cool, dark, stable room, away from exterior walls, plumbing and the floor.

Handle sheets with two hands, flat, or carry them on a supporting board. Never lift a large sheet by one corner: the tear that results runs from the corner into the image.

What to avoid entirely

Do not attempt to remove foxing, stains, tape or old repairs. Household bleaching agents destroy paper.

Do not trim a sheet, for any reason.

Do not flatten a rolled work by force. Rolled paper requires controlled humidification and is not a domestic job.

Do not write on the verso, and do not apply adhesive labels.

Do not store in polyvinyl chloride sleeves; use inert polyester where a sleeve is wanted, and not at all where the surface is friable.

Photographs

Photographs need the additional caution set out in [collecting early photography](/guides/collecting-early-photography). Colour prints in particular should be considered display-limited from the outset, and cased objects such as daguerreotypes should never have their seals opened outside a conservation studio.

When to consult a conservator

Active mould, water damage, insect activity, a tear entering the image, flaking media, or a work adhered to its glazing. Do nothing first: an untouched problem is far easier to treat than one that has been attended to at home.