Process for producing paper
First Claim
Patent Images
1. A process for producing paper comprising:
- subjecting a photographic paper support which has been internally sized with alkyl ketene dimer and strengthened with a combination of polyacrylamide and polyamide epichlorohydrin resin and has an absolute dry moisture content (moisture content in absolute dry condition) of 1.8-7% to a heat calendaring treatment at a temperature of 150°
-300°
C. under a linear pressure of 70-130 kg/cm; and
after said heat calendering treatment, introducing an aqueous solution containing one or more surface strengthening agents to adjust the final moisture content to 6% or more, said surface strengthening agent being selected from the group consisting of polyvinyl alcohol, starch, casein, gelatin, SBR, NBR and polyacrylamide.
0 Assignments
0 Petitions
Accused Products
Abstract
A paper having an absolute dry moisture content (moisture content in absolute dry condition) of 1.8-7% is subjected to a heat calendering treatment at a temperature of 150°-300° C. under a linear pressure of 40 kg/cm or above to provide a paper which has both satisfactory surface smoothness and rigidity (stiffness) and is suited for use as a photographic support.
46 Citations
19 Claims
-
1. A process for producing paper comprising:
-
subjecting a photographic paper support which has been internally sized with alkyl ketene dimer and strengthened with a combination of polyacrylamide and polyamide epichlorohydrin resin and has an absolute dry moisture content (moisture content in absolute dry condition) of 1.8-7% to a heat calendaring treatment at a temperature of 150°
-300°
C. under a linear pressure of 70-130 kg/cm; andafter said heat calendering treatment, introducing an aqueous solution containing one or more surface strengthening agents to adjust the final moisture content to 6% or more, said surface strengthening agent being selected from the group consisting of polyvinyl alcohol, starch, casein, gelatin, SBR, NBR and polyacrylamide. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
Specification