Base for photographic paper

Abstract

Abstract PURPOSE:To eliminate a die lip contamination and to prevent the generation of neck-in by using a polyolefin resin having the SR value (the expansion ratio of a molten resin) within a specific range as the base material to be used for a surface resin coating layer. CONSTITUTION:The polyolefin resin contained in the surface resin coating layer has the value, within the 1.4-1.9 range, of the SR which is measured by a melt extrusion test under the conditions of 10mm length of the capillary by a capillary rheometer, 1mm inside diameter of the capillary, 200 deg.C melt resin temp., and 1000 1/sec shearing rate and is calculated by SR=d/D (where SR denotes the expansion ratio of the molten resin; (d) denotes the diameter in the position apart 10mm from the capillary outlet of the molten resin flow extruded from the capillary; D denotes the inside diameter of the capillary). The contamination of the die lip generated in the melt extrusion coating stage is prevented in this way and the hiding property when the resin is made into the photographic paper is enhanced. The sharp photographic image is thus obtd.

Inventors

• 👤 Masahiro Kamiya
• 👤 神谷　昌博
• 👤 Tsunehisa Omotani
• 👤 重谷　恒久

Bibliographic Details