The particle transfer roller, often abbreviated to PTR, is a device for cleaning

motion picture film Film stock is an analog medium that is used for recording motion pictures or animation. It is recorded on by a movie camera, developed, edited, and projected onto a screen using a movie projector. It is a strip or sheet of transparent ...

. It consists of a cylindrical roller coated with

urethane Urethane may refer to: * Ethyl carbamate, a chemical compound which is an ester of carbamic acid * Polyurethane, a polymer composed of a chain of organic units joined by carbamate (urethane) links *Carbamate In organic chemistry, a carbamate is ...

, over which the surface of the film passes.

History

The particle transfer roller was developed by

Eastman Kodak The Eastman Kodak Company (referred to simply as Kodak ) is an American public company that produces various products related to its historic basis in analogue photography. The company is headquartered in Rochester, New York, and is incorpor ...

and launched in 1989. It was intended to replace the

organic solvent A solvent (s) (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for p ...

s that were the main method of film cleaning before that point. Although their effectiveness is not usually considered sufficient for

lab Lab most often refers to: * Laboratory, a facility to conduct scientific research Lab or LAB may also refer to: Places * Láb, a village near Bratislava in western Slovakia * Lab (river), in north-eastern Kosovo People * ISO 639 code for the an ...

operations, where

ultrasonic cleaning Ultrasonic cleaning is a process that uses ultrasound (usually from 20 to 40 kHz) to agitate a fluid, with a cleaning effect. Ultrasonic cleaners come in a variety of sizes, from small desktop units with an internal volume of less than , to large ...

with a solvent solution remains the standard, the PTR sold widely for use in projection booths and transfer houses.

Use

At least two PTRs are needed in the film path – one for the base side and one for the emulsion side – though four are frequently used. A set of PTRs is frequently placed in the film paths of

projectors A projector or image projector is an optical device that projects an image (or moving images) onto a surface, commonly a projection screen. Most projectors create an image by shining a light through a small transparent lens, but some newer type ...

telecine Telecine ( or ) is the process of transferring film into video and is performed in a color suite. The term is also used to refer to the equipment used in the post-production process. Telecine enables a motion picture, captured originally on ...

machines,

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 telepathic ...

and

printers Printer may refer to: Technology * Printer (publishing), a person or a company * Printer (computing), a hardware device * Optical printer for motion picture films People * Nariman Printer (fl. c. 1940), Indian journalist and activist * James ...

in order to remove dust and contaminants from the surface of the film before projection, transfer or duplication. PTRs are also used in some dedicated film cleaning machines, or mounted between rewind heads and used for manual cleaning. The contaminants are lifted from the film and adhere to the roller as the film passes in contact with it. The rollers themselves are then cleaned, usually in soapy water, and dried before the next use.

References

External links

Page on PTRs
on the

National Film and Sound Archive The National Film and Sound Archive of Australia (NFSA), known as ScreenSound Australia from 1999 to 2004, is Australia's audiovisual archive, responsible for developing, preserving, maintaining, promoting and providing access to a national c ...

of Australia's site. Film and video technology Film and video terminology Film production {{film-tech-stub