Postage stamp paper

Postage stamp paper is the foundation or substrate of the postage stamp to which the ink for the stamp's design is applied to one side and the adhesive is applied to the other. The paper is not only the foundation of the stamp but it has also been incorporated into the stamp's design, has provided security against fraud and has aided in the automation of the postal delivery system.

Stamp catalogs like Scott's Standard Postage Stamp Catalog (SC) often document the paper the stamp is printed on to describe a stamp's classification. The same stamp design can appear on several kinds of paper. Stamp collectors and philatelists understand that a stamp's paper not only defines a unique stamp but could also mean the difference between an inexpensive stamp from one that is rare and worth more than its common counterpart.

Making an accurate determination of the stamp's paper may require special tools such as a micrometer to measure the thickness of a stamp, certain fluid chemicals to reveal hidden features, magnifying glasses or loupes to see fine details, digital microscopes to examine the minutest details of the paper or ultraviolet light to illuminate the paper to reveal its glowing aspects. Certain paper types may require the services of an expert as the only sure way of knowing the true identity of the stamp's paper.

All paper is endowed with certain characteristics by its maker. 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.

The making of paper can be broken down into three phases; the preparing of the pulp into a suspension of fibers; the forming of the paper on a mould or an endless wire mesh; and lastly the finishing of the paper's surface and drying. From a philatelic interest, it is the second phase, the forming of the paper that yields the most interesting characteristics.

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