P
PACKAGING
The paper and board used for wrapping or packing goods.
PAPYRUS
An ancient writing material made from the stem of the papyrus plant, an African reed. Although the word “paper” is derived from papyrus, papyrus is not paper.
PARCHMENT
A sheet of writing material made from animal skin, nowadays usually used to denote Vegetable Parchment, or parchmentized papers. These have a high resistance to the penetration of grease and atmospheric humidity. Used largely for wrapping purposes, there are also grades of imitation parchments that are less impervious. Similar to greaseproof paper. See also Vellum Paper.
PASTEBOARD
This grade of board consists of one or more layers, usually of pulp board, pasted together. It may be lined both sides with paper of one type or another, depending on end use.
PERFECTING
The process of printing both sides of a sheet of paper in the same pass through the press
PERMANENT PAPER
Paper free from mechanical woodpulp or unbleached fiber, generally neutral/alkaline sized and containing calcium carbonate filler, made to controlled pH value and alkali reserve, intended for the printing of books and similar works for posterity.
PERNICIOUS CONTRARIES
Any material present in wastepaper that is difficult to see or detect, that might be detrimental to the paper being manufactured from the wastepaper or that might either damage papermaking equipment or render repulping difficult.
PHLOROGLUCINOL SOLUTION
An acidic spot test agent for paper that manufactures a red coloration in contact with lignified fiber.
PHOTOSETTING
A procedure of composing text matter directly onto a photographic or other light sensitive material.
PH VALUE
A number on a logarithmic scale extending from 0.3 to 14.5 which indicates the active acidity or alkalinity of an aqueous liquid. Neutrality is represented by pH 7.07, figures descending below this reading indicating increasing amounts of acidity, and those above, alkalinity.
PICKING
The lifting of fibers out of the paper due to the ink being too tacky. It causes small white dots in the solid areas of the printing.
PIPING
Deficiency in reels, consisting of ridges running around the circumference, due to moisture take-up by the surface layers.
PLATE CYLINDER
The cylinder on a press where the plate is mounted.
POSTER PAPER
Grade with a quick-drying surface used for outdoor poster work. The rough bottom side lends itself to rapid pasting.
PRESSPAHN
This is a German word used to describe a grade of board used for a variety of purposes, often industrial. It is light weighted, extra hard, rolled and friction glazed. Presspahn is a proven surface insulation material on cellulose basis for the insulation class A. Depending on the type of cellulose, fibre conditioning and machinery settings
PRESSURE SENSITIVE COATED PAPER
Paper coated with a self-adhesive material that, in dry form (solvent-free), is regularly tacky at room temperature. A bond with the receiving surface may be formed by the application of pressure (e.g., by the finger or hand). A permanent adhesive is characterized by relatively high ultimate adhesion; a removable adhesive by low ultimate adhesion. Until the time of application, the adhesive surface should be covered by a suitable release-coated paper.
PROOF
A pre-production print, made for the purpose of checking the accuracy of layout, type matter, tone and color reproduction.
PULP
Chemical pulp is made from a cellulose raw material (generally wood) by treating it (cooking) with chemicals to separate the cellulose fibers and dissolve the lignin, etc., that binds them together. It can be bleached or unbleached. Mechanical pulp is made from wood by purely mechanical means, i.e., grinding or refining of chips; lignin and other impurities are not removed, and further processing (bleaching) is required if a white sheet is required. Fiber obtained from wood by either of the above methods is called primary, or virgin, fiber. Some pulping processes involve both methods and also include heat treatment.
PULP BOARD
Also known as Printers’ Board, this grade is made from a single web of pulp on a papermaking machine, and is produced in various substances. Used for index cards and other general products, these boards may be white or colored.
PULPER
Any apparatus intended to slush pulp or paper.
RAG PAPER
Paper made from stock containing a substantial percentage of rag pulp. The minimum proportion of such pulp required for a paper to be so designated cannot be specified as it varies from country to country and is Generally used for high quality stationery.
