A platen (or platten) is a platform with a variety of roles in printing or manufacturing. It can be a flat

metal A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

(or earlier,

wood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

en) plate pressed against a medium (such as

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, Textile, rags, poaceae, grasses, Feces#Other uses, herbivore dung, or other vegetable sources in water. Once the water is dra ...

) to cause an impression in

letterpress printing Letterpress printing is a technique of relief printing for producing many copies by repeated direct impression of an inked, raised surface against individual sheets of paper or a continuous roll of paper. A worker composes and locks movable t ...

. Platen may also refer to a

typewriter A typewriter is a Machine, mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of Button (control), keys, and each one causes a different single character to be produced on paper by striking an i ...

roller which friction-feeds paper into position below the

typebar A typewriter is a Machine, mechanical or electromechanical machine for typing characters. Typically, a typewriter has an array of Button (control), keys, and each one causes a different single character to be produced on paper by striking an i ...

s or print head. It can refer to the glass surface of a copier, and the rotating disk used to polish semiconductor wafers.

Applications

Office equipment

In office copiers and

scanners ''Scanners'' is a 1981 Canadian science fiction horror film written and directed by David Cronenberg and starring Stephen Lack, Jennifer O'Neill, Michael Ironside, and Patrick McGoohan. In the film, "scanners" are psychics with unusual telep ...

, the platen is a flat

glass Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...

surface on which operators place papers or books for scanning. The platen is also called the flatbed. Platens are also used in some printers, such as the

dot-matrix printer Dot matrix printing, sometimes called impact matrix printing, is a computer printing process in which ink is applied to a surface using a relatively low-resolution dot matrix for layout. Dot matrix printers are a type of impact printer that p ...

Manufacturing and processing

Semiconductor manufacturing

In semiconductor manufacturing, specifically chemical-mechanical planarization, a flat, rotating platen covered with a pad is used to polish semiconductor wafers (see image).

Screen printing

In textile

screen printing Screen printing is a printing technique where a mesh is used to transfer ink (or dye) onto a substrate, except in areas made impermeable to the ink by a blocking stencil. A blade or squeegee is moved across the screen in a "flood stroke ...

, a platen is a flat board onto which the operator slides the

garment Clothing (also known as clothes, garments, dress, apparel, or attire) is any item worn on a human human body, body. Typically, clothing is made of fabrics or textiles, but over time it has included garments made from animal skin and other thin s ...

. It is generally made of either a plywood laminate or aluminum with a rubber laminate. Often the platen will be pretreated with a spray adhesive. This allows the garment to effectively become a rigid immobile substrate, especially important when printing multiple colors or utilizing an on-press infrared dryer. The screen is brought parallel and close to the garment (often within 1/32") and the squeegee pressure then brings the screen into contact with the garment so that the ink transfer may occur. There are many special platen types, such as those for printing sleeves or pockets, vacuum platens, platens with clamps to hold bulky materials such as jackets, and even curved platens for printing on hats.

Woodworking

In woodworking, wide

belt sander A belt sander or strip sander is a sander used in shaping and finishing wood and other materials. It consists of an electric motor that turns a pair of drums on which a continuous loop of sandpaper is mounted. Belt sanders may be handheld and ...

s use platens to press the sanding paper into contact with the wood being sanded. The platen sits between two steel rolls which deliver the moving force to the sanding belt. Sanding heads with a platen are used on finish sanding with papers of finer grits, when the coarser ones are typically used with contact drum type sanding heads. Stock is fed into and out of the machine on a conveyor belt. Since the abrasive belt creates a substantial pressure on the stock that tends to push the stock toward the infeed, the hold down shoes and rollers hold the workpiece down against the belt while it is moving through the machine in order to ensure uniform contact with the abrasive and continuous movement.

Metal forming

In metal forming processes, a platen is the component that houses the

mold A mold () or mould () is one of the structures that certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal ...

for

forging Forging is a manufacturing process involving the shaping of metal using localized compression (physics), compressive forces. The blows are delivered with a hammer (often a power hammer) or a die (manufacturing), die. Forging is often classif ...

the required shape. The platen tends to be the heaviest and strongest part of the press due to the massive forces that it has to withstand. A platen for a 5000-ton press can weigh up to 350 tons.

Other

In manufacturing, a platen is a flat plate of a press utilized in

laminate Simulated flight (using image stack created by μCT scanning) through the length of a knitting needle that consists of laminated wooden layers: the layers can be differentiated by the change of direction of the wood's vessels Shattered windshi ...

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

and forest product industries. A platen is typically heated with oil, water, steam or electricity and is used in the production of furniture, tires,

gasket Some seals and gaskets A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. It is a deformable material that is used to c ...

s, particle board, composite heaters and

plywood Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboa ...

. In high frequency

welding Welding is a fabrication (metal), fabrication process that joins materials, usually metals or thermoplastics, primarily by using high temperature to melting, melt the parts together and allow them to cool, causing Fusion welding, fusion. Co ...

products, platens are used to put lines on

PVC Polyvinyl chloride (alternatively: poly(vinyl chloride), colloquial: vinyl or polyvinyl; abbreviated: PVC) is the world's third-most widely produced synthetic polymer of plastic (after polyethylene and polypropylene). About 40 million tons o ...

binders and folders down the spine lines. Platens are utilized in impact testing in research; a

specimen Specimen may refer to: Science and technology * Sample (material), a limited quantity of something which is intended to be similar to and represent a larger amount * Biological specimen or biospecimen, an organic specimen held by a biorepository f ...

is crushed between platens. The platen also refers to the fixed part of a linear motor.

Gallery

File:Gutenbergpresse 01.jpg, Replica of the

Gutenberg press A printing press is a mechanical device for applying pressure to an inked surface resting upon a print medium (such as paper or cloth), thereby transferring the ink. It marked a dramatic improvement on earlier printing methods in which the c ...

. The platen on the right holds the paper, and is pressed down onto the typeset. File:Large SMG00176993.jpg, Cylindrical platen on a typewriter File:Star-LC-10-printer-02.jpg, Cylindrical platen in a dot-matrix printer

References

External links

{{Letterpress Printing