JP2001001635A - INK JET RECORDING MEDIUM AND ITS MANUFACTURING METHOD - Google Patents

Abstract

(57) [Problem] To provide a method for producing an ink jet recording medium capable of performing fine and clear printing, and having excellent water resistance and bleeding resistance. An average particle size is 10 to 500 nm on a substrate.
Applying a coating solution containing inorganic particles and an emulsion in which resin particles having a larger average particle size than the inorganic particles are dispersed,
A method for producing an ink jet recording medium which is dried to form an ink receiving layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording medium, and more particularly, to an ink jet recording medium capable of forming a high-quality image by an ink jet method and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, with the spread of electronic still cameras or computers, hard copy technology for recording such images on paper or the like has rapidly developed. The ultimate goal of these hard copies is silver halide photography. In particular, how to approach color reproduction, color density, resolution, gloss, weather resistance, and the like to silver halide photography has become an issue for development. Hard copy recording methods include a sublimation thermal transfer method, an ink jet method, and an electrostatic transfer method. Above all, ink jet printers have been rapidly spreading in recent years due to their low cost, easy full color printing, and abundant printing media. In this method, ink droplets are ejected from a nozzle toward a recording material at a high speed, and a large amount of solvent is contained in the ink. For this reason, a recording medium for an ink jet printer is required to absorb ink quickly and have excellent color developing properties.

Further, in addition to the above-described ink absorbing property and color developing property, in the ink jet recording system, an image is often formed using a water-based ink. It is also important that the ink does not occur and that the dye contained in the ink does not flow and the ink does not bleed.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing an ink jet recording medium which can print fine and clear images, and is excellent in water resistance and bleeding resistance.

[0005]

Means for Solving the Problems The present invention provides a coating composition comprising an inorganic particle having an average particle diameter of 10 to 500 nm and an emulsion in which resin particles having an average particle diameter larger than the inorganic particle are dispersed on a substrate. Provided is a method for manufacturing an ink jet recording medium in which a working liquid is applied and dried to form an ink receiving layer.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The substrate used in the present invention is not particularly limited, and various substrates can be used. For example,
Plastics, specifically, polyester resins such as polyethylene terephthalate, polycarbonate resins, fluorine resins such as polytetrafluoroethylene, and various papers, fabrics, glass, metals, ceramics such as tiles, etc. are used. it can. It is preferable that the base material is a fabric because the texture becomes soft and no post-treatment is required. These substrates may be subjected to a corona discharge treatment or various undercoats for the purpose of improving the adhesive strength of the porous layer containing the inorganic particles. Although the form of the substrate is not limited, a sheet or film having a thickness of 0.01 to 1 mm is usually used.

In the method for producing an ink jet recording medium of the present invention (hereinafter referred to as the present production method), an inorganic particle having an average particle diameter of 10 to 500 nm and a resin having an average particle diameter larger than the inorganic particle are formed on a substrate. A coating liquid containing an emulsion in which particles are dispersed (hereinafter referred to as a main coating liquid) is applied and dried to form an ink receiving layer.

The inorganic particles used in the present invention (hereinafter referred to as the present inorganic particles) are not particularly limited as long as the average particle diameter is in the range of 10 to 500 nm, but boehmite is preferred from the viewpoint of ink absorbency and the like. Boehmite is Al ₂ O ₃
Alumina hydrate represented by a composition formula of nH ₂ O (n = 1 to 1.5). The average particle diameter of the present inorganic particles,
When the inorganic particles are aggregated, the average particle size of the aggregated particles is used. When the inorganic particles are dispersed as primary particles, the average particle size of the primary particles is used.

The emulsion used in the present invention may be any emulsion in which resin particles having a larger average particle diameter than the present inorganic particles are dispersed. As the resin, a polyurethane resin,
It is preferably at least one selected from the group consisting of an acrylic resin, an ethylene / vinyl acetate copolymer resin, a polyethylene resin, a polypropylene resin, a carboxylated styrene / butadiene copolymer resin and a polyester resin. The present coating liquid may contain a defoaming agent, a dispersant, an antioxidant, a dye fixing agent, a thickener, or a binder component such as polyvinyl alcohol.

The ink receiving layer formed from the present coating liquid is a porous layer containing the present inorganic particles. The ink receiving layer has a pore volume peak in the range of 10 to 100 nm in pore diameter, and has a pore volume peak in the range of 10 to 100 nm. When observed with a scanning electron microscope, the pore diameter is 0.1 to
It is also preferred to have pores in the range of 10 μm.

Further, pores having a pore diameter in the range of 0.1 to 10 μm when observed with a scanning electron microscope can be controlled by the average particle diameter of the resin particles. That is,
The larger the average particle size of the resin particles, the larger the pore diameter.

As a means for applying the present coating liquid onto a substrate, a roll coater, an air knife coater, a blade coater, a rod coater, a bar coater, a comma coater, a die coater, a gravure coater, or the like is preferably employed.

[0013]

EXAMPLES [Example 1 (Example)] Average particle diameter of aggregated particles 1
An aqueous polyurethane emulsion (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Superflex E2) in which polyurethane resin particles having an average particle diameter of 1.6 μm are dispersed in 100 parts by weight (solid content) of a boehmite sol having a thickness of 90 nm and a pH of 3.5.
000) (in terms of solid content), and water was further added to prepare a coating solution having a solid content of 10% by weight. This coating liquid was impregnated onto a polyester fabric having a basis weight of 90 g / m ² so that the coating amount at the time of drying was 20 g / m ^2.
Dried at 0 ° C.

Example 2 (Example) Used in Example 1 for 100 parts by weight (in terms of solid content) of silica sol (catalyst SI-45P, trade name, manufactured by Catalyst Chemical Industry Co., Ltd.) in which spherical silica particles having an average particle diameter of 40 nm are dispersed. Water-based polyurethane emulsion (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Superflex E)
2000), and 100 parts by weight (in terms of solid content) were added, and water was further added to prepare a coating solution having a solid content of 10% by weight. This coating solution was impregnated onto a polyester fabric having a basis weight of 90 g / m ² so that the coating amount during drying was 20 g / m ^2.
Dried at 20 ° C.

Example 3 (Comparative Example) The polyester cloth used in Example 1 was used without any coating.

Example 4 (Comparative Example) Example 1 without inorganic particles
Water was added to the water-based polyurethane emulsion (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Superflex E2000) to prepare a coating solution having a solid content of 10% by weight. This coating liquid was impregnated onto a polyester fabric having a basis weight of 90 g / m ² so that the coating amount at the time of drying was 20 g / m ^2.
Dried at ° C.

[Test Method] Printing was performed using an ink-jet plotter (manufactured by Graphtec Co., Ltd., trade name: Master Jet Printer JC1005) in solid colors of cyan, magenta, yellow, black, red, green, and blue.

The bleeding is visually observed, and the result is observed in a single color 10
When the solid portion of 0% oozes, X is applied, when the solid portion of 200% of mixed color oozes, and when the solid portion does not bleed, 〇. The color density was measured using a color densitometer (trade name SPM100-I, manufactured by Gretag).
It measured by I) and showed by the average value of four colors of CMYK.

The water resistance was measured by immersing a cloth left for one hour after printing in water, rubbing the printed part with a finger, and visually observing the presence or absence of falling off. The results were as follows: な い for which no dropout was observed, も の for partially dropped out by color, and × for dropped out regardless of color.
And

The pore characteristics up to a pore diameter of 100 nm were measured using a nitrogen adsorption / desorption device (Omni Soap 10 manufactured by Coulter Co., Ltd.).
0). The pore diameter is 0.1 to 10 μm
Scanning electron microscope (manufactured by JEOL Ltd.,
(Trade name: JSM-5300). The pore diameter corresponding to the peak of the pore volume obtained by the nitrogen adsorption / desorption apparatus was designated as pore diameter 1, and the pore diameter of the pores observed with a scanning electron microscope was designated as pore diameter 2. Table 1 shows the evaluation results.

[0021]

[Table 1]

[0022]

According to the present production method, the color development of the ink is good.
It is suitable as a method for producing an ink jet recording medium having excellent water resistance and bleeding resistance. Further, among the pores formed in the ink receiving layer of the ink jet recording medium obtained by the present production method, those having pore diameters in the range of 0.1 to 10 μm observed by a scanning electron microscope are described. The pore diameter can be controlled by the average particle diameter of the resin particles dispersed in the coating liquid.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // C08L 101: 00

Claims (6)

[Claims] (1) An average particle diameter of 10 to 500 nm on a substrate.
Applying a coating solution containing inorganic particles and an emulsion in which resin particles having a larger average particle size than the inorganic particles are dispersed,
A method for producing an ink jet recording medium which is dried to form an ink receiving layer. 2. The resin particles dispersed in the emulsion are polyurethane resin, acrylic resin, ethylene / vinyl acetate copolymer resin, polyethylene resin, polypropylene resin, carboxylated styrene / butadiene copolymer resin and polyester resin. The method according to claim 1, which is at least one member selected from the group consisting of: 3. The method according to claim 1, wherein the inorganic particles are boehmite. 4. An ink jet recording medium obtained by the method according to claim 1, 2 or 3. 5. The ink receiving layer according to claim 1, wherein the pore diameter is 10 to 100.
The inkjet recording medium according to claim 4, wherein the medium has a pore volume peak in the range of nm, and also has pores having a pore diameter in the range of 0.1 to 10 µm when observed with a scanning electron microscope. 6. The ink jet recording medium according to claim 4, wherein the substrate is a cloth.