Postage stamp paper
Depending on the purpose of the paper, the craftsman will choose specific materials and apply certain manufacturing processes to achieve the design objectives.
Characteristics such as composition, weight, color, size, watermark, surface finish, opacity, hardness and strength all have to be established before the papermaker can begin his work.
Cellulose has several characteristics that make it desirable for paper, the foremost being its strength when formed into a mat or web.
Fillers and sizing are added to the pulp to absorb the ink quickly, unlike pure cellulose.
Fillers can be glues made from animal products, starches from rice or wheat, resins or gums, or minerals such as calcium carbonate, titanium dioxide or kaolin.
When all of these ingredients are assembled, they are suspended in water, which may include a color dye, as the furnish to the second phase of papermaking.
The mould determines the dimensions of the finished sheet and its weight, which ultimately establishes the paper's thickness.
In comparison, machine-made paper is made on the Fourdrinier machine by drawing the furnish out of a vat onto an endless wire mesh.
For example, a stronger paper may have needed a higher number of perforations per inch to best facilitate the separation of the stamps.
Similarly, many stamps have two different standards of perforation for its length and width to optimize the ease of separation while minimizing the cost of manufacturing.
Watermark detection can be as simple as holding the stamp up to a light or by placing it face down on a black surface.
A rare flaw in paper is when the watermark bit has been improperly repaired on the Dandy roll.
Similarly, off-paper is used to describe a postally used stamp that is no longer adhering to any other kind of paper.
The first that is typically encountered in the stamp catalogs describes the texture of the paper, such as wove or laid.
As a super fine calendared paper that is coated with china clay to give it an enameled finish, it is useful for printing fine-screen half-tone blocks.
To identify colored paper, examine both sides of the stamp including the perforated edges.
There is tinted paper as well as surface-colored stamps (Great Britain's White Backs as an example), where color was applied intentionally after the normal processes of papermaking were finished.
Normally, these seams were cut from the sheets but occasionally these double paper stamps slipped the inspector's eye and entered into post office stocks.
But because double paper stamps became so common, Scott's stopped listing them with a special designation.
Granite paper has colored (typically red and/or blue) silk fibers added to the furnish.
↔ The texture of oblong quadrille results from wires on the paper mould that form a rectangular pattern.
The term palimpsest actually is defined as parchment or velum that has been reused to the extent that the previous writing can still be faintly seen.
Philatelically, paper that was originally designed to be used for another purpose and then used for printing of stamps is also categorized as palimpsest.
The most famous are from Latvia, when after World War I, the Latvian government printed stamps on the back of German military maps.
Later, Latvia printed stamps on the backs of unfinished banknotes of the Bolshevists and the government of Colonel Bermondt-Avalov.
Stamps printed on pelure paper sometimes do not survive wholly intact because of their brittle nature.
↔ Luminescence is a characteristic of the mineral zinc orthosilicate, which glows a yellowish-green when illuminated with shortwave ultraviolet light.
Quadrille describes the texture of this paper, where the laid lines form small squares about 1/8 of an inch.
John Dickinson patented silk-thread paper in 1830 for bank notes and later adapted the technology for stamps.
↔ A paper to which a luminescent additive was added to the furnish to facilitate the automation of the facing and canceling operation.
