Inkjet-recording medium, production method thereof, inkjet-recording method, inkjet-recording set, and inkjet-recording object

Abstract

The present invention provides an inkjet-recording medium having an ink-receiving layer at least containing a cationic polyurethane resin and a water-soluble bivalent metal salt, wherein the coating amount of the cationic polyurethane resin x (g/m2) and the coating amount of the water-soluble bivalent metal salt y (g/m2) satisfy the relationships of 0.3≦x≦5.0 and 0.01x≦y≦0.5x.

Description

Claims

1. An inkjet-recording medium comprising: a substrate andan ink-receiving layer, formed on the substrate,the ink-receiving layer comprising at least a cationic polyurethane resin and a water-soluble bivalent metal salt, whereinthe coating amount of the cationic polyurethane resin x (g/m2) and the coating amount of the water-soluble bivalent metal salt y (g/m2) satisfy the relationships 0.3≦x≦5.0 and 0.01x≦y≦0.5x.

2. The inkjet-recording medium of claim 1, wherein the water-soluble bivalent metal salt is at least one of a water-soluble magnesium salt or a calcium salt.

3. The inkjet-recording medium of claim 1, wherein the coating amount of the water-soluble metal salt is 0.01 to 0.5 g/m2.

4. The inkjet-recording medium of claim 1, wherein the water-soluble metal salt is magnesium chloride.

5. The inkjet-recording medium of claim 1, wherein the ink-receiving layer further comprises a water-soluble binder and the water-soluble binder is a polyvinylalcohol.

6. The inkjet-recording medium of claim 1, wherein the ink-receiving layer further comprises a crosslinking agent and the crosslinking agent is boric acid.

7. A method for producing an inkjet-recording medium by forming a crosslinked hardened ink-receiving layer on a substrate, the method comprising; forming a coated layer, by coating a first solution including a water-soluble binder and a crosslinking agent for crosslinking the water-soluble binder onto a substrate andcrosslinking and hardening the coated layer by applying a second solution containing a basic compound onto the coated layer formed by coating either (1) simultaneously with application of the first solution or (2) in the period before the coated layer shows a falling drying rate when the coated layer is drying, whereinat least one of the first and second solutions comprises a cationic polyurethane resin, at least one of the first and second solutions contains a water-soluble metal salt, and the coating amount of the cationic polyurethane resin x (g/m2) and the coating amount of the water-soluble bivalent metal salt y (g/m2) satisfy the relationships 0.3≦x≦5.0 and 0.01x≦y≦0.5x.

8. An inkjet-recording set, comprising the inkjet-recording medium according to claim 1 and a water-soluble ink comprising at least one water-soluble phthalocyanine dye.

9. The inkjet-recording set of claim 8, wherein the water-soluble phthalocyanine dye is a dye satisfying the relationship ε1/ε2>1.2, wherein ε1 is a molar absorption coefficient as determined from the absorbance at the maximum wavelength in the spectroscopic absorption curve when an aqueous solution of the dye at a concentration of 0.1 mmol/l is measured by using a cell having an optical path length of 1 cm, and ε2 is a molar absorption coefficient as determined from the absorbance at the maximum wavelength in the spectroscopic absorption curve when an aqueous solution of the dye at a concentration of 0.2 mmol/l is measured by using a cell having an optical path length of 5 μm.

10. The inkjet-recording set of claim 8, wherein at least one of the water-soluble phthalocyanine dyes is at least one compound selected from compounds represented by the following Formula (1) and salts thereof:

11. The inkjet-recording set of claim 8, wherein at least one of the water-soluble phthalocyanine dye(s) is a mixture of a phthalocyanine compound represented by the following Formula (2) having at least one unsubstituted sulfamoyl group and a phthalocyanine compound represented by the following Formula (2) having at least one substituted sulfamoyl group containing an ionic hydrophilic group:

12. An inkjet-recording method for recording an image, the method comprising ejecting ink droplets of a water-soluble ink comprising a water-soluble phthalocyanine dye onto the inkjet-recording medium of claim 1.

13. The inkjet-recording method of claim 12, wherein the water-soluble phthalocyanine dye is a dye satisfying the relationship of ε1/ε2>1.2, wherein ε1 is a molar absorption coefficient determined from the absorbance at the maximum wavelength in the spectroscopic absorption curve when an aqueous solution of the dye at a concentration of 0.1 mmol/l is measured by using a cell having an optical path length of 1 cm, and ε2 is a molar absorption coefficient determined from the absorbance at the maximum wavelength in the spectroscopic absorption curve when an aqueous solution of the dye at a concentration of 0.2 mmol/l is measured by using a cell having an optical path length of 5 μm.

14. The inkjet-recording method of claim 12, wherein the water-soluble phthalocyanine dye is at least one compound selected from compounds represented by the following Formula (1) and salts thereof:

15. The inkjet-recording method of claim 12, wherein the water-soluble phthalocyanine dye is a mixture of a phthalocyanine compound represented by the following Formula (2) having at least one unsubstituted sulfamoyl group and a phthalocyanine compound represented by the following Formula (2) having at least one substituted sulfamoyl group containing an ionic hydrophilic group:

16. An inkjet-recording object, the object carrying an image recorded by the inkjet-recording method of claim 12.