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Saws, drills, and other mechanical methods can be used to remove the bulk of protruding materials; however, scratches, chips, and breaks can occur. [4]: p.77–78 Filler material can also be removed chemically. Typically, chemical removal is used once the bulk of filler material is left and only a small portion is left.
The separating funnel relies on the concept of "like dissolves like", which describes the ability of polar solvents to dissolve polar solutes and non-polar solvents to dissolve non-polar solutes. When the separating funnel is agitated, each solute migrates to the solvent (also referred to as "phase") in which it is more soluble.
With paintings, a variety of organic solvents are used, but the most common solvent is water, often with chelating agents, surfactants or salts to control pH. Applying solutions through tissues, gels and sponges is becoming the norm, due to the level of control offered by holding the cleaning system at the upper surface of the art.
A suspension is a heterogeneous mixture in which the solid particles do not dissolve, but get suspended throughout the bulk of the solvent, left floating around freely in the medium. [1] The internal phase (solid) is dispersed throughout the external phase (fluid) through mechanical agitation, with the use of certain excipients or suspending ...
This may be used in the fixing of delicate pieces of art as well as in book conservation to loosen and clean off old glue from spines and bookboards. [citation needed] Methyl cellulose is the main ingredient in many wallpaper pastes. It is also used as a binder in pastel crayons and also as a binder in medications. Hydroxypropyl methylcellulose ...
Chalk carving is the practice and shaping of chalk via carving. This article covers some methods, types of chalk, tools used and the benefits (and ramifications) of this material. The benefits of this material are also its drawbacks. Its main benefit, its softness, makes it very easy to manipulate.
Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO 4 ·2H 2 O. [4] It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, drywall and blackboard or sidewalk chalk.
A diagram showing surface erosion (left) and bulk erosion (right). In surface erosion, the material only degrades on the surface which causes the material to “shed off” its surface over time. In bulk erosion, the material loses volume throughout equally, which is represented by the fading colors.