Editing Parchment (section)

== Additional uses of the term ==
In some universities, the word parchment is still used to refer to the certificate (scroll) presented at graduation ceremonies, even though the modern document is printed on paper or thin card; although doctoral graduates may be given the option of having their scroll written by a calligrapher on vellum. [[Heriot-Watt University]] still uses goatskin parchment for their degrees.{{Citation needed|date=April 2025}}

=== Plant-based parchment ===
{{See also|Parchment paper (baking)}}
{{unreferenced section|date=September 2018}}
'''Vegetable (paper) parchment''' is made by passing a waterleaf (an unsized paper like blotters) made of pulp fibers into [[sulfuric acid]]. The sulfuric acid hydrolyses and solubilises the main natural organic polymer, cellulose, present in the pulp wood fibers. The paper web is then washed in water, which stops the hydrolysis of the cellulose and causes a kind of cellulose coating to form on the waterleaf. The final paper is dried. This coating is a natural non-porous cement, that gives to the vegetable parchment paper its resistance to grease and its semi-translucency.

Other processes can be used to obtain grease-resistant paper, such as waxing the paper or using [[fluorine]]-based chemicals. Highly beating the fibers gives an even more translucent paper with the same grease resistance. Silicone and other coatings may also be applied to the parchment. A [[silicone]]-coating treatment produces a cross-linked material with high density, stability and heat resistance and low surface tension which imparts good anti-stick or release properties. [[Chromium]] salts can also be used to impart moderate anti-stick properties.