M
M Weight
The weight of one thousand sheets of paper, any size; or double the ream weight.
M2 Yield/Ton
A measure of the surface area of paper/paperboard which is obtained from a ton of paper.
Machine Chest
Usually the last large chest or tank that contains thick-stock pulp before it is made into paper.
Machine Clothing or Paper Machine Clothing
Fabrics of various types employed on the paper machine to carry the web and perform other functions. It includes the machine wire, dandy roll cover, press felts and dryer felts etc., which may be composed of natural or synthetic materials.
Machine Crepe
Crepe paper produced on the paper machine, and not as a secondary option.
Machine Direction
The direction of the web through the paper machine.
Machine Finish
Finished produced on the paper as it leaves either the machine or the calender stack. For increased printability, or smoothness when used as a liner, etc.
Machine Glazed
Machine glazed. Paper with a glossy finish on one side produced on the paper machine by a Yankee cylinder.
Machine Speed
The rate at which paper machine runs, expressed as m/min or ft/min.
Machine Width
Width of the paper web in the paper machine.
Manifold Paper
A light weight bond paper used for making carbon or manifold copies or for airmail correspondence.
Manila
A semi-bleached chemical sulfate paper. Not as strong as Kraft, but have better printing qualities.
Manufacturing Order
Also known as making order. A quantity of paper manufactured to custom specifications, such as a special weight, color, or size not available as a standard stocking item.
Market Pulp
Pulp which is made to be used elsewhere for the production of paper. Usually dried to reduce freight costs but may be "wet lap" ( 50% water).
Marbling
Addition of strongly stained fibers to the stock to give the paper a marbled appearance.
Matte Finish
A dull, clay-coated paper without gloss or luster.
Maximum Trimmed Width
The greatest width of usable paper that is possible to make on a given paper making machine, i.e. the full width less the necessary trim to give clean edges. There is 3-10% width shrinkage (depending on freeness of stock) in dryers. It is not possible to specify sizes which, in aggregate, exceed this width.
Mechanical Paper
This paper contains mechanical pulp, thermomechanical pulp (TMP) or chemithermo-mechanical pulp (CTMP) and also chemical pulp. The shares of chemical and mechanical pulp vary depending on the application. Highly mechanical papers such as newsprint tend to yellow more rapidly if exposed to light and oxygen than woodfree papers so that they are mainly used for short-lived products. In printing papers the mechanical pulp improves opacity.
Mechanical Pulp
Pulp produced by mechanically grinding logs or wood chips. It is used mainly for newsprint and as an ingredient of base stock for lower grade printing papers.
Medium Density Fiberboard (MDF)
A composite panel made from wood fibers and resin and formed under pressure and heat. MDF has a smooth surface and good machinability, and is used for furniture, cabinetry and millwork.
Mesh
Count of wires per inch for metal and/or plastic screen used in paper mill.
Metamerism
The tendency of color to appear different under different light sources such as fluorescent or natural sunlight.
MG Machine
A paper machine incorporating a Yankee or a MG drying cylinder in the drying section to produce MG paper.
Micro Crystalline Cellulose Pulp
Like Ethers Pulps, these pulps are used in thickening and pharmaceutical applications, particularly in construction of tablets and other non-capsular pills.
Mil
One thousandth of an inch.
Mill
The physical site where paper is manufactured; also refers to a company that manufactures paper.
Mill Broke
Paper generated at the paper mill prior to completion of the manufacturing process. Wet mill broke originates at the wet end of the papermaking machine, while dry mill broke comes from the dry end of the papermaking machine.
Millboard
A thick, dense, homogeneous board, for book production, made generally from wastepaper, on a special board making machine one sheet at a time. Used in binding case bound books, ledgers etc. as binders’ boards.
Mineral Filler
Materials such as chalk and china clay that are added to paper in order to change its density or improve its surface and optical properties.
Mitsumata
A bast fiber used in Japanese papermaking that yields a soft, absorbent and lustrous quality.
Mixed Office Waste
Wastepaper generated from offices, such as letters, memos, invoices, etc. which are collected and sorted for paper qualities. This is the major source of post consumer fiber.
Modified Starch
Papermaking starch that has been processed generally by oxidation, to achieve lower viscosity or chemical characteristics which are beneficial in use as an additive in papermaking.
Moisture Content
The amount of moisture or water in a sheet of paper, expressed in percent. 6 to 7% is desirable.
Moisture Resistant
Paper Treated with asphalt, wax, plastic, etc. to control penetration of moisture.
Molding Pulp
Pulp, which is used for producing pulp-based or fibrous products by pressing; example products: egg packages, trays and boxes for fruits and vegetables.
Mordant
Chemical added to pulp to improve the fixation of dyes to the fiber.
Mottle
A random non-uniformity in the visual density, color or gloss of a printed area; also known as orange peel, back-trap mottle, wet-trap mottle, pigment flocculation, striations, etc.
Mottling Fiber
Heavily dyed fibers added to a different color stock furnish to produce characteristic surface effects.
Mullen
Measurement of the force required, in pounds per square inch, to rupture a sheet of kraft paper. Also known as bursting strength.
Multi-stage Cooking
Chemical pulping process in which the alkalinity of the cooking liquor is varied by charging the alkali in several stages.
Multiply Board Machine
A machine in which a number of plies of paper can be combined together in the wet state to produce thick paperboard..
Multiply Paper Making Process
A paper/board making process in which different layers of fibers are deposited one over the other to form the sheet. The multiply process is used to make the optimum use of various type of fibers available. It is also used to make heavy basis weight papers.
