摘要:
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.
摘要:
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−1)/(TDDR1/2−1), wherein TDDR is greater than 4 at an end of the stretching region.
摘要:
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.
摘要:
An apparatus for processing a film includes a conveyor and an isolated takeaway device. The conveyor includes gripping members that hold opposing edge portions of the film and convey, under influence of a drive member, the film along a machine direction within a stretching region of the apparatus. The conveyor, over substantially the entire stretching region, is configured and arranged to provide diverging, substantially parabolic paths along which the gripping members move to stretch the film. The isolated takeaway device receives the film from the conveyor and includes gripping members to grasp opposing takeaway regions of the film directly from the stretching region and convey the film in the machine direction. In another embodiment, the conveyor provides diverging curvilinear paths along which the gripping members move to stretch the film. An isolated takeaway device includes opposing flexible, continuous gripping mechanisms for grasping opposing takeaway regions of the film.
摘要:
A personal respiratory protection device that comprises a mask body and an exhalation valve that is secured to the mask body. The mask body includes (i) a flat central panel; (ii) a flat first panel joined to the central panel through a fold-line, seam weld, or bond, the fold-line, seam, weld or bond of the first panel being substantially coextensive with an edge of the central panel; (iii) a flat second panel joined to the central panel through a fold-line, seam, weld or bond, the fold-line, seam, weld or bond of the second panel being substantially coextensive with an edge of the central panel. At least one of the center, first and second panels includes filter media. The device is capable of being folded for storage with the first and second panels in at least partial face-to-face contact with a common surface of the central panel and, during use, is capable of forming, over the nose and mouth of the wearer, a cup-shaped air chamber having a face-contacting periphery.
摘要:
A personal respiratory protection device that comprises a mask body and an exhalation valve that is secured to the mask body. The mask body includes (i) a flat central panel; (ii) a flat first panel joined to the central panel through a fold-line, seam weld, or bond, the fold-line, seam, weld or bond of the first panel being substantially coextensive with an edge of the central panel; (iii) a flat second panel joined to the central panel through a fold-line, seam, weld or bond, the fold-line, seam, weld or bond of the second panel being substantially coextensive with an edge of the central panel. At least one of the center, first and second panels includes filter media. The device is capable of being folded for storage with the first and second panels in at least partial face-to-face contact with a common surface of the central panel and, during use, is capable of forming, over the nose and mouth of the wearer, a cup-shaped air chamber having a face-contacting periphery.