3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

Jeffery N Jackson

William Ward Merrill

Andrew T Ruff

John Allen Wheatley

Dennis L Krueger

Desiree L Thompson

Martin E Denker

Timothy J Hebrink

Carl A Stover

Kristopher J Derks

Dee Lynn Johnson

Richard J Thompson

Harvey D Ogren

David R Cram

Michael F Weber

Thomas P Hanschen

Robert D Taylor

Kevin M Hamer

Joan M Strobel

Anthony B Ferguson

William B Black

Fred J Roska

Gregory L Bluem

John P Purcell

Chiu Ping Wong

Barry S Rosell

Jeffrey D Amundson

Curtis A Harvey

Anna A Kobilansky

Takashi Fujita

Matthew B Johnson

Craig E Hamer

Joseph T Bartusiak

Gary William Schukar

Neil J Schwartzbauer

Anna A Wetzels

Susan J Newhouse

John F Macklin

Desiree L Tompson

Karl A Stover

A multilayer optical film includes a plurality of alternating polymeric first and second layers numbering at least 20 in total. The polymeric first layers include between about 10% and 50% by weight of polyethylene terephthalate and between about 50% and 90% by weight of polyethylene naphthalate. For a substantially normally incident light and for a visible wavelength range, the multilayer optical film has respective average optical transmissions of between about 10% and 30% when the incident light is polarized along a first direction and greater than about 60% when the incident light is polarized along an in-plane orthogonal second direction. For a p-polarized incident light and for at least one wavelength in an infrared wavelength range, the multilayer optical film has optical transmissions T1 and T2 for respective incident angles of less than about 10 degrees and greater than about 40 degrees, wherein T2−T1 is less than about 40%.

Multilayer optical film, roll of multilayer optical film, backlight, and display system

A stretcher for processing a film is described. In particular, stretcher receives a film, graps edge portions of the film, conveys the film in a machine direction, and moves the opposing edge portions along diverging; substantially parabolic paths to form a stretched film.

Processes and apparatus for making transversely drawn films with substantially uniaxial character

A film () processing apparatus () including a film stretching device () and a take-away device () and a film processing method using the apparatus. The take-away device receives the film after the stretching device and transports the film along a conveying region in a direction of transport (X). The take-away device includes opposing, first and second conveyor assemblies. The first conveyor assembly has a continuous belt driving a plurality of discrete pads (). Each pad forms a contact face () extending between leading () and trailing edges (). The pads are configured and arranged such that the trailing edge () of a first pad () overlaps the leading edge () of an immediately adjacent second pad () as the first and second pads traverse the conveying region. The overlap is characterized by a line () perpendicular to the direction of transport passing at any given moment through the first and second pads. A shape of the contact face can define a major central axis that is non-perpendicular and non-parallel with the direction of transport.

Apparatus and method for stretching and taking-away polymer films

The present disclosure is directed to optical bodies including a first optical film, a second optical film and one or more strippable boundary layers disposed between the first and second optical films. Each major surface of a strippable boundary layer may be disposed adjacent to an optical film or another strippable boundary layer. At least one of the first and second optical films may include a reflective polarizer. The present disclosure is also directed to methods of processing such optical bodies.

Optical bodies including strippable boundary layers

Optical bodies are disclosed that include a first optical film, a second optical film and at least one rough strippable boundary layer disposed between the first and second optical films. Also disclosed are optical bodies including a strippable boundary layer disposed between the first and second optical films and including a first polymer and a second polymer that is substantially immiscible in the first polymer. The present disclosure also provides methods of processing optical bodies that include stretching the optical bodies.

Optical bodies including rough strippable boundary layers

Optical bodies are disclosed that include an optical film and at least one rough strippable skin layer. The at least one rough strippable skin layer can include a continuous phase and a disperse phase. In some embodiments, the at least one rough strippable skin layer can include a first polymer, a second polymer different from the first polymer and an additional material that is substantially immiscible in at least one of the first and second polymers. In some exemplary embodiments, a surface of the at least one rough strippable skin layer adjacent to the optical film comprises a plurality of protrusions and the adjacent surface of the optical film comprises a plurality of asymmetric depressions substantially corresponding to said plurality of protrusions. Methods of making such exemplary optical bodies are also disclosed.

Optical bodies including rough strippable boundary layers and asymmetric surface structures

A roll of multilayer optical film is described. The roll includes a substantially uniaxially-oriented multilayer optical film, where at least one layer of the multilayer optical film has indices of refraction in a length direction and a thickness direction that are substantially the same, but substantially different from an index of refraction in a width direction.

A stretcher for substantially uniaxially orienting a film includes a plurality of gripping members to hold opposing edge portions of the film, paths along which the gripping members travel to stretch the film in a stretching region, and a drive mechanism to convey the film and gripping members along a machine direction. At least a portion of the paths in the stretching region define diverging, curvilinear courses disposed in-plane. The paths are configured such that during the stretching an extent of uniaxial character, U, is between zero and unity and a minimum value of an extent of uniaxial character, U, is at least 0.70 over a final portion of the stretching after achieving a TDDR of 2.5. U is defined as U=(1/MDDR&#x2212;1)/(TDDR&#x2212;1), wherein TDDR is greater than 4 at an end of the stretching region.

Stretched polymeric films can be used in a variety of applications, including optical applications. The stretching conditions and shape of the stretching tracks in a stretching apparatus can determine or influence film properties. Methods and stretching apparatuses can include adjustable or zone-defined stretching regions.

Devices for stretching polymer films

A process for stretching films is described. The process preferably stretches films in a uniaxial fashion. Preferably, optical films are stretched including multilayer optical films. Other aspects of the invention include a roll of stretched film and an apparatus for stretching films.

Apparatus for making transversely drawn films with substantially uniaxial character

Stretched polymeric films can be used in a variety of applications, including optical applications. The stretching conditions and shape of the stretching tracks in a stretching apparatus can determine or influence film properties. Take-away systems can be used to receive the film after stretching. The configuration of the take-away system can, in at least some instances, influence final film properties.

Devices for conveying, stretching, and taking-away polymer films

Methods and devices for stretching polymer films

A method of stretching films in which all or a portion of the width of the film is cooled during or just after stretching so as to improve the uniformity of the film. The includes stretching a polymeric film in a tenter that grasps the film with a plurality of clips along the opposing edges of the film and propels the clips to thereby stretch the film. The tenter includes driven clips and idler clips, with at least one idler clip between respective pairs of driven clips. The cooling is done so as to improve the uniformity of the clip spacing relative to the spacing obtained at otherwise identical process conditions without such cooling.

Method of stretching film

Growing community of inventors

Woodbury, MN, United States of America

Jeffery N Jackson