Coated paper sheet
AssigneeOji Paper Co., Ltd.
InventorsHarumi Watanabe, Atsushi Myojo, Hiroyuki Wakasa, Osamu Kitao
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Abstract
A coated paper sheet provided with a coating layer formed on a paper sheet substrate and containing a pigment and a binder and optionally a pre-coated polyacrylamide-containing anionic acrylic resin layer formed between the substrate and coating layer, and having a 75° specular gloss of 70% or more, an air permeability of 4000 seconds or less, a Clark stiffness, in terms of critical strength L, of 12 cm or more in a cross direction and an internal bond strength of 200 mJ or more, exhibits high resistance to blistering, excellent printer-passing property, and high quality image-recording property and useful for both of offset printing and electrophotographic duplicating or printing.
Claims3
A coated paper sheets usable for on-demand-printing purposes using an offset press or an indirect drying electrophotographic printer,
- comprising:
- a paper sheet substrate and
- a coating layer formed on at least one surface of the sheet substrate by coating an aqueous dispersion liquid comprising, as principal components, a pigment and a binder, drying the coated liquid layer and smoothing the dried coating layer, and having a 75 degrees specular gloss of 70% or more, determined in accordance with TAPPI T480 om-92, wherein the paper sheet substrate is one surface-sizepressed, during a paper-forming procedure for the paper sheet substrate, with an aqueous sizepress liquid containg an anionic acrylic resin which comprises a copolymer of 50% by mass or more of acrylamide with 1 to 40% by mass of acrylonitrile and 1 to 20% by mass of at least one member selected from acrylic acid and methacrylic acid, in a dry solid amount of 0.5 to 3 g/m2 and has a basis mass of 50 to 110 g/m2,
- wherein the coated paper sheet has an air permeance, and
- wherein the coated paper sheet exhibits, as a whole,
- (1) an air permeability of 4000 seconds or less, determined in accordance with JIS P 8117 using Type B testing device,
- (2) a Clark stiffness, in terms of a critical length L, of 12 cm or more, determined in a cross direction of the coated paper sheet in accordance with JIS P 8143 using a Clark stiffness tester and a specimen having a width of 30 mm, and
- (3) an internal bond strength of 200 mJ or more, determined in accordance with TAPPIUM 403.
Dependencies are inferred from the claim text.