Abstract: An ink-jet recording sheet comprising a substrate having thereon a porous layer formed by a process comprising the steps of: (a) coating on the substrate an aqueous coating composition containing a hydrophilic binder and inorganic particles to form the porous layer; (b) drying the porous layer over a period, wherein the period comprises at least a constant drying rate period and a falling drying rate period; and (c) incorporating a solution containing an additive into the porous layer after the completion of the constant drying rate period.

Abstract: A ink-jet recording sheet comprising on a support an ink absorptive layer containing minute silica particles, hydrophilic binder and water-soluble multivalent metal compounds; wherein said ink absorptive layer is composed of at least tow layers, and the peak of distribution of the amount of the water-soluble multivalent compounds in the depth direction is located within 10 ?m from the uppermost surface, and the weight ratio of the water-soluble multivalent metal compounds to minute silica particles in the uppermost layer of the ink absorptive layer, and the dried coating thickness of the uppermost-layer, have specific ranges.

Abstract: A method for manufacturing ink jet recording sheet having the steps, in that order, of: providing an under-coat layer on a polyolefin coating support having the center-line average roughness of the surface of the polyolefin coated support of 0.10 to 1.5 ?m as measured at a reference length of 2.5 mm and a cutoff value of 0.8 mm; heating the polyolefin coated support on which the under-coat layer is provided; and coating on the under-coat layer a coating liquid that contains inorganic micro particles and binder so that the coating liquid forms a porous ink absorption layer, wherein the temperature difference between the temperature of the polyolefin coated support and the temperature of the coating liquid is within 15° C. in the coating step.

Abstract: A manufacturing method for a porous ink-jet recording sheet is accomplishable by applying a water base coating composition onto a non-water-absorbing substrate and drying that coating, in which water base coating composition, in which a wet thickness H and a dry thickness D satisfy a specific relationship, and additionally a content of inorganic micro-particles and a viscosity are within specified ranges.

Abstract: An inkjet recording medium having: a support on which polyolefin resin is coated; and a porous ink absorbing layer containing a hydrophilic binder and inorganic fine particles, which is provided on the support, wherein a surface facing to the ink absorbing layer of the support is a fine-grained surface having about 5 through 10 rugged configurations arranged regularly at intervals of 3 mm; and wherein the surface has the center-line average roughness is not less than 2.5?m when a reference length is 2.5 mm and a cutoff value is 0.8 mm, and the ratio of the ten-point mean roughness of the surface to the center-line average roughness thereof is 4 to 7.

Abstract: A manufacturing method for manufacturing an ink-jet recording material having a support carrying a first layer and an ink-receiving layer in that order. The method includes emulsion polymerizing a monomer in the presence of a polymer dispersant having at least a hydroxyl group for preparing a resin; first coating a first coating liquid including the resin onto the support to form the first layer; and second coating a second coating liquid to form the ink-receiving layer.

Abstract: An ink-jet recording sheet comprising a paper support coated with a polyolefin resin on both sides of the paper support, the polyolefin resin-coated paper support having thereon a porous ink receptive layer containing a hydrophilic polymer, wherein the paper support has a ratio of a Cobb value to a basis weight of not more than 0.05:1 to 0.4:1.

Abstract: An ink-jet recording sheet comprising a substrate having thereon a porous layer formed by a process comprising the steps of:

Abstract: An ink jet recording sheet comprising a non-water absorptive support having thereon an ink absorptive layer comprising polyvinyl alcohol, a cationic polymer, and a compound containing a zirconium or aluminum atom other than zirconium oxide and aluminum oxide, wherein a surface pH of the ink absorptive layer is 4 to 6 measured 30 minutes after receiving a water based ink of pH range 6 to 9 jetted from an ink jet printer in an amount of 20 ml/m2.

Abstract: An aqueous coating composition is disclosed. The composition comprises fine organic particles, polyvinyl alcohol, and boric acids or salts thereof and comprising substantially no gelatin, and the same having a viscosity of 10 to 100 cp at 40° C., and a viscosity at 15° C., which is at least 20 times as much as that at 40° C. A coating method of the composition and an ink-jet sheet prepared by employing the composition are also disclosed.

Abstract: The present invention is to provide a ink-jet recording sheet of high ink absorptive property, high cockling resistance, high surface smoothness, low cost, and high image quality with incorporating specially designed void-forming absorptive layer whose absorptiveness is determined by a ratio of a Bristow Test value and a Cobb value.

Abstract: An ink jet recording sheet is disclosed, comprising a support having on at least one side of the support an ink absorbing layer, wherein the surface of the ink absorbing layer side of the sheet exhibits a center-line mean roughness (Ra) of 0.4 to 2.5 &mgr;m and a ten-point mean roughness (Rz) of 5×Ra to 20×Ra when measured at a reference length of 2.5 mm and a cut-off value of 0.8 mm.

Abstract: An ink jet recording medium is disclosed. The recording medium comprises a support and a porous ink absorbing layer comprising inorganic particles and hydrophilic binder which is hardened employing inorganic hardener and organic hardener. The ink jet recording medium exhibits high ink absorbability and desired water resistance without degrading layer brittleness through sufficiently hardening the layer employing an appropriate amount of hardeners.

Abstract: An aqueous coating composition is disclosed. The composition comprises fine organic particles, polyvinyl alcohol, and boric acids or salts thereof and comprising substantially no gelatin, and the same having a viscosity of 10 to 100 cp at 40 ° C., and a viscosity at 15 ° C., which is at least 20 times as much as that at 40 ° C. A coating method of the composition and an ink-jet sheet prepared by employing the composition are also disclosed.

Abstract: An ink-jet recording sheet comprising a substrate having thereon a porous layer formed by a process comprising the steps of:

Abstract: An ink-jet recording material comprising a support having thereon a first layer and an ink-receiving layer in that order, wherein the first layer comprising a resin polymerized by emulsion polymerization in the presence of a polymer dispersant having at least a hydroxyl group; and the ink-receiving layer comprising water-soluble binder and inorganic particles having an average particle diameter of 3 to 200 nm.

Abstract: An ink jet recording sheet is disclosed. The recording sheet comprises a water non-absorptive support and a porous ink absorptive layer comprising dicyandiamide polycondensation product on the support.

Abstract: An ink jet recording sheet comprising a non-water absorptive support having thereon an ink absorptive layer comprising polyvinyl alcohol, a cationic polymer, and a compound containing a zirconium or aluminum atom other than zirconium oxide and aluminum oxide, wherein a surface pH of the ink absorptive layer is 4 to 6 measured 30 minutes after receiving a water based ink of pH range 6 to 9 jetted from an ink jet printer in an amount of 20 ml/m2.

Abstract: An ink jet recording sheet having a support and an ink absorption layer provided on the support wherein a center line average roughness (Ra) is 0.8 to 4.0 &mgr;m, measured at a standard length of 2.5 and a cut-off value of 0.8 mm of the surface of the ink jet recording sheet on the ink absorption layer side, which is specified in JISB-0601, and a 60-degree specular gloss of the ink jet recording sheet is 10 to 30 percent, which is specified in JIS-Z8741.

Abstract: An ink-jet recording sheet is disclosed. The recording sheet comprises ink absorption layers containing a cationic substance on both sides of a support having an opacity of not less than 94% according to JIS P 8138.