A series of metal rolls at the end of a paper machine; when the paper is passed between these rolls, it increases its smoothness, gloss and reduces it's bulk.
Calendered
Paper that has been smoothed and polished between sets of rollers called a calender; this process is usually done at the dry end of a papermaking machine.
Caliper
Thickness of paper measured in microns (1000microns = 1mm).
Carbon Footprint
The amount of carbon dioxide (or equivalent greenhouse gases) related to a product or service, for a defined scope. For example, emissions caused by extraction of raw materials, manufacture (energy use) and transport might be included in a carbon footprint.
Carbon Offsetting/Carbon Neutral
Organisations can calculate their carbon footprint and pay to 'offset' it by planting trees or by investing in energy-efficient technologies in developing countries, which are intended to absorb or reduce carbon emissions by an equivalent amount. There are a number of schemes that can facilitate carbon offsetting. 'Carbon Neutral' is a trademark of one such scheme, run by the Carbon Neutral Company.
Carbonless Paper
Paper commonly used to produce multi-part business forms. Chemically transfers images from one sheet to another without carbon paper. The sheets are coated on one or two sides with an emulsion of colourless dyes and oils. A set is made up of three types of papers: 1. CB (coated back), which is the top, white sheet in the set; 2. CF (coated front), which is the bottom sheet; 3. CFB (coated front and back), which is used for middle sheets of a multi-part form. The accepted colour sequence is White, Canary Yellow, Pink, Green, Golden.
Cast Coated
Paper coated and dried against a polished cylinder for a high-gloss finish.
Cast coating
A process which gives paper an extremely glossy enamel finish.
Catalyst
A substance which has the capability of initiating or accelerating the speed of a reaction between two or more substances when introduced into their presence, normally in small quantities.
CCD
Charged Coupled Device. Light sensitive cells used in digital cameras and digital exposing devices.
CD Rom
Compact Disk
Chain of Custody
The means of tracking a product along the supply chain. For instance, being able to trace paper from the forest of origin, through pulp and paper mill, paper merchant and printer to the end user. Often a third party audits the Chain of Custody system, as with the FSC and PEFC schemes.
Chain of Custody
The means of tracking a product along the supply chain. For instance, being able to trace paper from the forest of origin, through pulp and paper mill, paper merchant and printer to the end user. Often a third party audits the Chain of Custody system, as with the FSC and PEFC schemes.
Charpy Test
Impact test in which a notched specimen, which is fixed at both ends, is struck behind the notch by a striker carried on a pendulum. The energy absorbed in fracture is measured by the height to which the pendulum rises.
Charpy Test
Impact test in which a notched specimen, which is fixed at both ends, is struck behind the notch by a striker carried on a pendulum. The energy absorbed in fracture is measured by the height to which the pendulum rises.
Chemi-Thermo Mechanical Pulp (CTMP)
Same as TMP only chips are also sprayed with chemicals.
Chemical Pulp
Pulp made by cooking the wood in the presence of chemical agents (acids or alkali) which eliminates most of the non-fibrous material.
CHP
Combined Heat and Power. A power-generating unit that provides heat and electricity on site rather than drawing energy from the grid. CHP units can have the benefit of proportionally lower emissions to air than power stations. Many paper mills use CHP.
Cliché
Used in pad printing. The "inkable" steel or nylon plate that is etched with an image to be transferred on to the silicone pad and then to the part.
Clogging
Premature drying of ink in the screen, causing bad print by blocking part of the open stencil.
CMYK
A subtractive colour model used for full-colour printing. Cyan, Magenta, Yellow and Black inks are combined to produce the maximum range of colours with the most efficient use of ink.
CO2
Carbon dioxide, a greenhouse gas that contributes to climate change
CO22
Carbon dioxide, a greenhouse gas that contributes to climate change
Coalescence
The pooling or puddling of ink on inkjet output. A common defect in low-quality media.
Coated Paper
Paper or Board with a coating to produce a smooth, ink receptive finish that will enhance the sharpness and gloss of the printed image.
Coating
A layer of minerals applied to one or both sides of paper or board to improve brightness, gloss and printability; the coating is held together and stuck to the paper by a binder.
Cobwebbing
Fine filaments produced by the ink between the screen and the printing surface resulting in a cobweb-like appearance on the finished print. Sometimes called angel hair.
Cockle
The puckering or wrinkling of inkjet output. Caused by expansion of paper fibres as a result of overloading the ink receptive layer with ink.
COD
Chemical Oxygen Demand. A measure of the amount of oxygen required for the chemical breakdown of organic matter in effluent.
Cold Pressed
A paper surface with slight texture produced by pressing the finished sheet between cold cylinders.
Cold-Set Inks
A variety of inks that are in solid form originally but are melted in a hot press and then solidified when they contact paper.
Colour Gamut
The entire range of colours that can be reproduced by a particular printer or display. In printed output it depends upon the printer, ink and media.
Colour Laser
A laser printer in which four passes of the print mechanism lay down cyan, magenta, yellow and black toners to produce a colour image.
Colour Retention
Colour stability after exposure to the elements.
Combustible Liquid
Liquid having a flash point at or above 100 degrees Fahrenheit (37.8 degrees C) but less than 200 degrees Fahrenheit (93.3 degrees C).
Continuous Inkjet
One of the first implementations of the inkjet concept in which drops are expelled continuously from the print head and the image is formed by an electrostatic mechanism, which selects those drops that are allowed to pass through the selector to reach the paper. This is the basis of Iris and Stork printers. The technology employs very small drops and is therefore capable of high image quality.
Continuous Tone
Images that are represented, nor by dots or lines or primary colours, but by a series of evenly graduated tones, as in a photograph - sometimes referred to as a contone.
Converter
A company that specialises in converting reels and sheets of paper and board into packaging or finished goods for sale to the public.
Copier/Laser Papers
Lightweight grades of good quality and dimensionally stable papers used for copying correspondence and documents.
Core
A steel, wood or cardboard tube on which paper is reeled or re-reeled.
Core size
The inside diameter of the insert that the product is wrapped around.
Corona Discharge
An electrical surface treatment that encourages oxidation of a surface to reduce surface tension and improve ink adhesion.
Cover Paper
Heavyweight stock used for covers of catalogues, brochures, books or business cards.
CPET
Central Point of Expertise on Timber. A UK Government service that provides advice to Government buyers and their suppliers on how to meet the Government's requirements for purchasing timber products (including paper). See:www.proforest.net/cpet
Cratering
Undesirable depressions in the dried ink film that may be large enough to expose the substrate.
Crawling
The cohesive effect of ink into drops after printing onto a surface which the ink does not wet completely.
Crazing
A random pattern of tiny intersecting cracks in plastic, ceramic glaze or other surfaces.
Crocking
Image rub-off that occurs when a pigment or dye is not adequately fixed in the substrate.
Cross Direction
The direction across the grain. Paper is weaker and more sensitive to changes in relative humidity in the cross direction than in the grain direction.
CSA
Canadian Standards Association. In relation to paper, a forest certification scheme, now endorsed by the PEFC.
CSR
Corporate Social Responsibility. The continuing commitment by business to behave ethically and contribute to economic development while improving the quality of life of the workforce and their families as well as of the local community and society at large, including the environment.
Curl
Tendency of paper by itself to bend or partly wrap around the axis of one of its directions. Usually caused by changes in weather, faulty drying on the paper machine or in a multi-ply sheet with differing ply composition.
Cut-Off
A term used in web press printing to describe the point at which a sheet of paper is cut from the roll; usually this dimension is equal to the circumference of the cylinder.
