Eastman-Kodak Company

Timothy F Cilano

Larry K Maier

Diana C Petranek

Wen-Li A Chen

Frank D Manioci

Fred D Kelley

Michael Schild

Jeffrey P Johnson

A method for controlling the width of a polyester film support comprising, in order, the steps of: (a) extruding a polyester resin using one or more extruders; (b) casting the resin on a casting wheel to form a polyester sheet; (c) stretching the polyester sheet along the machine direction by ratios of 3 to 5 times at temperatures ranging from above the glass transition temperature to below the thermal crystallization temperature, wherein the machine contains extended edge rollers ( ) in the drafter at the point where stretching occurs; (d) stretching the polyester sheet along the transverse direction by ratios of 3 to 5 times at temperatures ranging from above the glass transition temperature to below the thermal crystallization temperature; and (e) heat setting the polyester sheet at temperatures ranging from 180 to 250&deg; C.

Method of controlling width of polyester film support

A silver halide light sensitive photographic element is disclosed comprising a polyethylene terephthalate film base, at least one light sensitive silver halide-containing emulsion layer, an antihalation undercoat layer, and a process-surviving antistatic backcoat, wherein the polyethylene terephthalate film base has been formed by drafting a cast resin at a stretch ratio of at least 3.4, tentering at a stretch ratio of at least 3.4, and heat-setting at an actual heat-set temperature of at least 216&deg; C. In accordance with preferred embodiments of the invention, the polyethylene terephthalate film base of the photographic element is formed by: (a) casting a molten polyethylene terephthalate resin in a machine direction onto a casting surface to form a continuous sheet, (b) drafting the sheet by stretching in the machine direction at a stretch ratio of from 3.4 to 4, and at a temperature ranging from 70 to 130&deg; C., (c) tentering the sheet in the transverse direction by stretching at a stretch ratio of from 3.4 to 4, and at a temperature ranging from 70 to 130 C., (d) heat-setting the tentered sheet at an actual temperature sensed by the sheet of at least 216&deg; C., and (e) cooling the heat-set sheet without substantial detentering to obtain a stretched, heat-set polyethylene terephthalate film.

Photographic element comprising polyethylene terephthalate film base and antihalation layer

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Pittsford, NY, United States of America

Timothy F Cilano