PULP AND PAPER DICTIONARY
This page contains definitions of the terms, words and phrase commonly used in pulp and papermaking, printing, converting and paper trading.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
T4S Abbreviation indicating that the paper has been guillotine trimmed on all four sides. Literal translation: trimmed four sides.
Table Roll The small diameter rolls used to support the wire.
TACK OR STICKINESS Tack is a critical property of the ink used in lithography. Because the ink sits on a flat surface, it needs internal cohesion; in other words, it needs to stick to itself so that it doesn't run all over the plate. However, too much tack can cause it to pull the paper apart.
When printing two or more ink colours in line, the ink tack and sequence must be adjusted in order for the inks to adhere to each other as well as to the paper.
TAD - Acronym for Through Air Dried, which is a special tissue papermaking technology that produces desirable lower density for the same strength, resulting in better bulk, absorptive capacity, and softness for the same amount of fiber (basis weight). The TAD fabric that carries the paper through this part of the paper machine leaves a characteristic impression in the tissue paper that looks like very fine and very faint embossing (see micro embossing). , which comes from the TAD fabric that carries the paper through this part of the paper machine. This technology is being used on bath tissue and paper towels, but only rarely (if ever) on paper napkins or facial tissue. More conventional tissue papermaking technologies include: Light Dry Crepe (LDC) and Heavy Wet Crepe (HWC).
TAG PAPER A heavy utility grade of paper used to print tags, such as the store tags on clothing. Tag paper must be strong and durable, yet have good affinity for printing inks.
TALC Mineral used in papermaking as a filler and coating pigment.
TEAR INDEX Tear index = tearing resistance/basis weight.
TEAR RESISTANCE The mean force required to continue the tearing of paper from an initial cut under standardized conditions.
TEAR STRENGTH A measure of how likely a paper will continue to tear once started. Tear strength will differ with and against the grain.
TECHNOLOGY CURVE A method for determining the entire range of performance of a process. The concept was originally developed by scientists and engineers at Scott Paper Company for use on papermaking processes and technologies. It has been adapted for use on finishing processes, and especially for embossing.
TENSILE ENERGY ABSORPTION (TEA) It is the work done when a paper specimen is stressed to rupture in tension under prescribed conditions as measured by the integral of tensile strength over the range of tensile strain from 0 to maximum.
TENSILE INDEX Tensile index = tensile strength (N/m) /basis weight (g/m2).
TENSILE STRENGTH A measure of how likely a paper is to break when pulled at opposite ends. This is very important when running through high-speed web presses.
TENSILE STRENGTH - The strength of a material when tested by pulling. In the absorbent tissue paper industry, this is usually reported as the maximum load that a one-inch wide specimen can bear before rupture, averaged over a number of specimens. The test can be done while the paper is dry or re-wetted (see wet strength). In most products, the test result is very dependent upon which direction the paper is pulled. The Machine Direction Tensile strength (MDT) is usually much greater than the Cross Direction Tensile strength (CDT). There are two other measurements that are often provided by the machine that performs the tensile test: Stretch and Energy. Of these, Machine Direction Stretch (MDS) is usually considered to be the most useful, and it is reported as the percentage of elongation of the test specimen at the moment that peak load occurred.
TESTLINER Mainly produced from waste paper used as even facing (as the outer layer) for corrugated board or as liner of solid board. They are often produced as duplex (two-layer) paper. The grammage is higher than 125 gsm.
TEXT PAPER Text papers are defined as fine, high quality uncoated papers. Typically, they are made in various colours, with numerous textures and a variety of surface finishes. Text papers are made from high-grade bleached wood pulp, cotton fibres, or tree-free pulp such as bamboo. Recycled sheets include high quality recycled waste paper and post-consumer waste pulp, in addition to bleached wood pulp, tree-free pulp or cotton fibres.
THERMAL PAPER Any paper with a heat-sensitive coating on which an image can be produced by the application of heat.
THERMAL TRANSFER PRINTING Printing whereby a design image is first printed on heat transfer paper using inks with sublimable dispersed dyes.
THERMO MECHANICAL PULPING (TMP) Mechanical pulp made by steaming wood chips under pressure prior to and during refining, producing a higher yield and stronger pulp than regular stone groundwood or regular refiner wood pulp.
THICKNESS OR CALIPER Thickness and caliper usually refer to a single layer (one sheet of product or one ply of paper), whereas bulk usually refers to a stack of layers. The problem with determining the thickness or caliper of a single layer is that the surface of an absorbent tissue paper is not only highly irregular, but also porous. There are always a few fiber ends protruding high above the rest, and holes that pass all the way through the paper. Neither of these have much effect upon how we normally think of thickness in a practical sense, and should be ignored. The preferred method of measuring the thickness of paper is to place it between two parallel flat plates that are pressed together with a predefined force. The gap between the plates is reported as the thickness of the paper. The test result is very dependent upon the pressure that is applied by the plates. The effect of embossing upon thickness is more obvious when a relatively light compressive force is used.
THIN PAPER Includes carbonizing, cigarette, bible, air mail and similar papers.
THINNING A practice in which certain trees are removed from a dense stand to allow the remaining trees adequate sunlight, nutrients and moisture to grow at an even rate.
TINT To vary a colour by adding white. Also, a very light or delicate variation of a colour.
TISSUE PAPER A low weights and thin sheet. Normally a paper sheet weighing less than 40 gram per meter square is called tissue.
TISSUE PAPER Paper that is very light in weight. There are two basic categories of tissue paper: wrapping tissue and absorbent tissue. Wrapping tissue paper is stronger, thinner, denser, and less porous than absorbent tissue paper, and is very rarely embossed. Absorbent tissue paper is often embossed to improve its absorbency even further.
At-Home products: Also known as Consumer Products, these are the tissue products you purchase in the grocery store and convenience store for use in your home and include toilet paper and facial tissue, napkins and paper towels, and other special sanitary papers.
Away-from-Home products: Also known as Commercial & Industrial Tissue, these are the products that serve markets such as hospitals, restaurants, businesses, institutions, and janitorial supply firms.
Specialty: These types of tissue papers are often high-end, decorative papers that are glazed, unglazed, or creped, and include wrapping tissue for gifts and dry cleaning, as well as crepe paper for decorating.
Facial tissue: The class of soft, absorbent papers in the sanitary tissue group. Originally used for removal of creams, oil, and so on, from the skin, it is now used in large volume for packaged facial tissue, toilet paper, paper napkins, professional towels, industrial wipes, and for hospital items. Most facial tissue is made of bleached sulphite or sulphate pulp, sometimes mixed with bleached and mechanical pulp, on a single-cylinder or Fourdrinier machine. Desirable characteristics are softness, strength, and freedom from lint.
TITANIUM DIOXIDE An opaque and expensive compound used as a white pigment and opacifier in papermaking. Elemental titanium is a lustrous, lightweight, white metal with exceptional strength.
TOILET TISSUE - See bath tissue.
TOLERANCE Permissible degree of variation from a pre-set standard.
TON ON TONNE Metric ton or Metric Tonne is equal to 1000 Kgs. or 2240 lbs. English tons are as defined. Long Ton = 2240 lbs is similar to metric ton. Standard English ton is 2200 lbs. Short ton is 2000 lbs.
TOP SIDE Side of the paper opposite to the wire side.
TOTAL ALKALI NaOH + Na2S + Na2CO3 + 0.5*Na2SO3 all expressed as Na2O in alkaline pulping liquor.
TOTALLY CHLORINE FREE (TCF) Totally chlorine free applies to virgin fibre papers that are unbleached or processed with a sequence that includes no chlorine or chlorine derivatives. (Also see ECF)
TOWEL - See paper towel.
TRANSLUCENCY The ability to transmit light without being transparent.
TRANSLUCENT DRAWING PAPER A paper suitable for drawing office use; sufficiently translucent for an image on it to be reproduced by processes using transmitted light and for a design to be traced on it from an original placed beneath it. Such processes include blueprint and diazo.
TRANSPARENCY Ability of paper to allow light rays to pass through so that objects behind it can be clearly seen.
TRANSPARENT PAPER Extended and particularly careful grinding of high quality fibres (hard chemical pulps, rags) yields a raw material permitting the production of transparent paper.
TREATED PAPER Papers which have functional characteristics added through special treatment. Among the most common are insect resistant, mould resistant, clay coated, and flame retardant.
TRIM To cut true to exact size, by cutting away the edges of paper in the web or sheet.
TUB SIZING The operation of surface sizing paper by passing it through a bath of a suitable solution such as gelatine.
TUBE DIGESTER Single or multi-tube continuous digester; used mainly in nonwood pulping and sawdust pulping purposes; horizontal tubes.
TWIN-WIRE MACHINE A papermaking machine with two continuous forming wires, rather than just one. Twin-wires were designed to create a less two-sided paper than paper manufactured on a Fourdrinier paper machine.
Other techniques for reducing two-sidedness have since been developed, enabling paper manufacturers to create paper on single-wire machines with little side-to-side variation.
TWO PARALLEL FOLD An excellent fold for legal size (or larger) pieces that are to be mailed. A legal sheet (8.5" x 14") is folded to 3.5" x 8.5". A 9" x 16" sheet produces a 4" x 9", four panel brochure. Note: A perforation added at one of the folds can create a three panel brochure with detachable reply card. For picture of this type and other fold please visit http://www.bradenprint.com/pdf/Folds-IS.pdf
TWO-SIDEDNESS The property denoting a difference in appearance and printability between its top (felt) and wire sides.