B
BACK UP
To print on the wrong side of a printed sheet.
BACKWATER
The liquid that passes through the forming surface when stock is deposited upon it. Backwater is essentially water, but mostly it contains dissolved matter or suspended matter such as fines, filler, etc. Backwater is normally recirculated within the papermaking process, or sent to a treatment plant for the recovery of materials in suspension.
BAGASSE PULP
Pulp obtained by chemical means from bagasse, the residue after the juice has been taken out of a sugar cane.
BAMBOO PULP
Pulp obtained by chemical means from the stems of bamboo, a type of grass common mostly to Asiatic countries.
BANKS AND BONDS
A range of printing and writing papers, the better qualities of which were at one time made largely from shreds of fabric. The heavier substance papers, above a substance of about 60g/m2, are often used for correspondence and letterheads and are known as bonds. The lighter weights, called banks, are used largely for file copy papers but have less use today with the introduction of the automated office.
BARK WASTE
A major source of energy for pulp mills. Raw wood is debarked before chipping with the bark being recovered and burnt at a steam power plant.
BASE PAPER
Paper intended to be converted, e.g., by a coating process or by fertilization. The term sometimes also used for paper to which a layer of other material (aluminum, plastic, etc.) is bonded. Also called Body Paper or Rawstock.
BEATING OR REFINING
The mechanical treatment of fibrous materials in a beater or clarifier to modify certain of their characteristics in order to give them the properties necessary for the manufacture of a desired quality of paper.
BIBLE PAPER
Very thin printing papers. Originally made particularly for bibles and prayer books, this grade of paper is also used for other commercial purposes – such as dictionaries – where many pages are required with an overall low volume. Bible paper is also known as India paper.
BINDER
The adhesive used to stick layers of coating together as well as to the paper or board surface. The most frequently used binder is starch, but synthetic binders are also used to give improved presentation.
BIODEGRADABLE
A material that will decompose as the result of action by bacteria and other living organisms.
BIOLOGICAL OXYGEN DEMAND (BOD)
This declares the amount of dissolved oxygen consumed by microorganisms as they decompose organic material in polluted or natural water. The higher the amount of decomposable material, the higher the BOD value.
BIOLOGICAL WASTE WATER TREATMENT
Different methods that are used by pulp and paper mills for purifying their wastewater (such as the activated sludge method). In these meyhods natural microorganisms decompose the organic substances. The organisms constitute a nutrient cycle consisting of bacteria, protozoa and higher organisms. The method reduces the biological oxygen demand by over 95% and removes about 50% of the organic compounds from effluent, organic chlorine compounds included.
BLACKENING
Defect associated with calendered paper occurring as unintended local areas of apparently darker or grayer color due, for example, to the paper being too moist when passed through the calender.
BLADE COATED PAPER
Paper coated by a process in which the freshly applied wet coating is smoothed and the leftover removed by a thin, flexible metal blade that bears on the coated surface.
BLANKET CYLINDER
The cylinder on a printing machine covered usually with a rubber blanket, which conveys the image from the plate to the sheet.
BLANKET-TO-BLANKET MACHINE
A printing machine in which the blanket cylinders act as opposing impression cylinders, allowing both sides of the web or sheet to be printed at the same time.
BLEED
The part of a printed image that is beyond the area in which the finished print will be cut.
BLISTER PACK
This term defines a packaging system that is a combination of board and plastics. The product is sealed to the board by a transparent plastic film. This system is often used for small products of difficult shapes and sizes.
BLOTTINGS
Highly occlusive papers that can be watermarked. With the advent of the ballpoint pen, the original use where handwriting ink is absorbed has greatly reduced demand.
BOARD
Heavy weight paper. The marking off the boundaries between paper and board is indeterminate. For many purposes it is taken as 220 or 225g/m2, but many products below these levels are described, commercially, as board.
BOD7
The biological oxygen demand of a wastewater sample, calculated over seven days’ exposure (also. BOD5, BOD10).
BOND
See Banks and Bonds
BREAKING LENGTH
The calculated limiting length of a strip of paper of any uniform width, beyond which, if such a strip were hang up by one end, it would break by its own mass.
BROKE
Paper and pieces of paper arising at any point in the mill that are appropriate only for repulping, e.g., wet paper removed from the paper machine or dry paper arising as trimmings, faulty paper, etc.
BRUSH COATING
A method of coating a web of paper in which the applied coating slip is scattered and smoothed by means of brushes, some stationary and some oscillating across the web.
BULK-PACKED ON PALLETS (BPOP)
A method of packing paper in which the sheets are not wrapped in parcels but piled on the pallet, tabbed at the required intervals to indicate quantity and over-wrapped.
BULKY MECHANICAL
A mechanical paper made to a specific caliper as opposed to a fixed grammage. Typical calipers are 102 and 127 microns. This type of paper, used mostly for mass-market paperback books, also has several uses when converted, such as cash register rolls.
BULKY PAPER
Paper that appears to be thick in association with its grammage.
BURST FACTOR
The quotient of the bursting power of a paper and its oven-dry grammage as defined in the standard method of test.
BURST INDEX
The quotient of the bursting power of a paper and its grammage in the conditioned state as defined in the standard method of test.
BURSTING STRENGTH
The combined tensile strength and stretch of a material as measured by the ability of the material to resist rupture when pressure is applied under specified conditions to one of its sides by an instrument used for testing the property. Testing for the bursting strength of paper is a very common procedure, although its value in determining the potential permanence or durability of paper is suspect
