Consolidant
Definition
A dilute polymer solution (Paraloid B-72, Klucel G, Cellugel) misted over a fragile char surface to stabilise the carbon matrix before handling or transport, preventing further fracture without altering ink chemistry or significantly penetrating the document.
- Field
- Charred document recovery
- Common agents
- Paraloid B-72, Klucel G, Cellugel
- Delivery method
- Misted over the char surface
- Purpose
- Stabilise carbon matrix before handling
- Must not do
- Alter ink chemistry or deeply penetrate
Common questions
Why mist a consolidant instead of brushing or spraying it directly?+
A charred page is extremely brittle and any direct contact pressure can shatter it. Misting deposits a fine, even film that binds surface carbon fragments together without mechanical force, letting the document be lifted and transported without further fracturing.
Does applying a consolidant interfere with later ink or fibre testing?+
A properly chosen dilute solution is selected specifically to sit on the surface rather than soak into the char, so it should not compromise infrared imaging of iron-gall or carbon inks. Examiners still document which consolidant and concentration was used, since some downstream chemical tests can be sensitive to surface coatings.
Related terms
- Ashing
- The terminal stage of heat damage, above approximately 400 degrees Celsius, in which carbon oxidises to carbon dioxide and only inorganic mineral...
- Charring
- The stage of heat damage at approximately 200 to 400 degrees Celsius at which paper cellulose converts to amorphous carbon; the sheet...
- Controlled Humidification
- Exposure of a charred document to 85 to 90 per cent relative humidity inside a sealed chamber, temporarily restoring pliability to the...
- Gelatine Tissue Lift
- A technique in which a fine-gauge gelatine tissue sheet, slightly humidified, is applied to a charred surface to lift a fragile carbon...
- Multispectral Imaging
- Photography or remote sensing in multiple wavelength bands beyond the visible spectrum, including near-infrared and short-wave infrared. Drone-mounted multispectral cameras are used...
- NIR Reflectance Imaging
- Photography of a document surface using illumination and camera detection in the near-infrared band (700 to 1100 nm), which differentiates carbon-based ink...
- Oblique-Light Photography
- Photography of a document surface using illumination at a low angle (10 to 15 degrees from the paper plane), which casts shadows...
- Principal Component Analysis (PCA)
- A multivariate statistical method used in fire debris research to reduce chromatographic data matrices to principal components that capture major variance. Used...
- Pyrolysis
- The thermal decomposition of cellulose in paper at approximately 150 to 300 degrees Celsius, disrupting glycosidic bonds and releasing water and carbon...