JPH11254817A - Powder paint-coated sheet and manufacture and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a powder paint-coated sheet having peculiar structure, a manufacture and use thereof, in particular, an image receiving sheet for ink jet recording. SOLUTION: The powder paint-coated sheet has a resin layer on the base material which is formed by being separated and isolated mutually by a substantially continuous film containing powder paint constitutional grains of an average grain diameter of 0.1-30 μm consisting of Inorganic minute grains of an average grain diameter of 1 nm-1 μm. The powder paint-coated sheet can be obtained by blending inorganic minute grains of an average grain diameter of 1 nm-1 μm in a powder paint composition of an average grain diameter of 0.1-30 μm then this is dry-coated on the base material before being fixed thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a powder coating sheet, its production and use, and more particularly to particles of a powder coating composition which are isolated from each other by a substantially continuous film of inorganic fine particles. The present invention relates to a powder paint-coated sheet having a separated resin layer on a base material, for example, powder, paint-coated paper, its production and use, and particularly to an image-receiving sheet for inkjet recording.

[0002]

2. Description of the Related Art Conventionally, various recording systems have been known. In recent years, an ink jet recording system has been widely used in which ink is ejected directly from a nozzle onto an image receiving paper and adhered to thereby perform recording. .

[0003] The image receiving paper used for the ink jet recording is conventionally manufactured by wet-coating a solution containing a resin and other additives on a base material and drying the solution to form a resin layer. That is, this resin layer in the ink-jet recording paper is composed of a resin layer containing a pigment in order to secure the absorbability and the color developing property of the aqueous inkjet ink, and to obtain the ink absorbency, the resin is:
It is used only when it is water-soluble or water-swellable. As described above, conventionally, by using a dedicated image receiving paper, a high-quality recorded image can be obtained for the first time by the ink jet recording method.

[0004] However, from the viewpoint of manufacturing, such a dedicated image receiving paper is formed by wet coating a resin or other additives on a base material to form a receptor layer, and therefore requires a solvent. At the time of removal, consideration for the environment is required, and furthermore, the resin used is limited as described above, and the obtained image receiving paper is expensive because of the large number of manufacturing steps and the use of organic solvents. It is.

[0005]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies on the production of an image receiving sheet for ink jet recording by dry coating of a powder coating composition instead of wet coating, and as a result, the powder coating composition The inorganic fine particles are mixed in a predetermined ratio to the product, and the mixture is dry-coated on a substrate, heated and melted, and fixed, whereby the film of the powder coating composition is substantially a continuous film of the inorganic fine particles. By being separated from each other, a separated resin layer can be formed on the base material, and the image receiving sheet for ink jet recording having such a resin layer as an ink receiving layer is not restricted by the resin used at all. The present invention has been found to be able to be manufactured at low cost by using an appropriate resin, and to be able to obtain a high quality ink jet recorded image.

Accordingly, an object of the present invention is to provide a powder-coated sheet having such a unique structure, a method for producing the same, and its use, and in particular, to provide an image-receiving sheet for ink-jet recording.

[0007]

Means for Solving the Problems The powder coating sheet according to the present invention has an average particle size (average value of primary particle size, hereinafter,
the same. ) The powder coating composition particles having a particle size of 0.1 to 30 µm have an average particle size (average value of primary particle size, hereinafter the same).
It is characterized by having a resin layer separated and separated from each other by a substantially continuous film of inorganic fine particles of 1 μm on a substrate.

The method for producing a powder coating sheet according to the present invention comprises mixing a powder coating composition having an average particle size of 0.1 to 30 μm with inorganic fine particles having an average particle size of 1 nm to 1 μm, Dry coating, heat melting, fixing, the particles of the powder coating composition are separated from each other by a substantially continuous film consisting of the inorganic fine particles, the separated resin layer on the substrate It is characterized by forming.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the production of a powder coating sheet according to the present invention will be described. Such a powder coating sheet according to the present invention has an average particle size of 0.1 to 30 μm.
m, preferably 1 to 20 μm, mixed with inorganic fine particles having an average particle diameter of 1 nm to 1 μm, dry-coated on a substrate, heated and melted, and fixed to obtain a powder coating composition. The particles of the composition can be obtained by forming a resin layer separated from each other by a substantially continuous film made of the above-mentioned inorganic fine particles and forming a separated resin layer on a substrate.

In the present invention, the substrate is usually
Paper, synthetic paper, synthetic resin sheet and the like are preferably used.
The paper is not particularly limited as long as it is made of ordinary cellulose fiber, and in addition to plain paper, high-quality paper,
Including coated paper. Examples of plain paper include ordinary PPC copy paper, paper subjected to calendering to enhance the smoothness of the surface of this PPC copy paper, and thermal transfer word processor paper and coated paper that have already been surface-treated. Can be mentioned. As the synthetic resin sheet, for example, polyester, polyvinyl chloride, polyethylene, polypropylene, polyethylene terephthalate,
Examples include sheets made of polycarbonate, polyamide, and the like. Examples of the synthetic paper include those obtained by extruding a mixture of a polyolefin resin or another synthetic resin as a resin component, a required inorganic filler, and the like. In particular, by using paper as the base material, the powder coating sheet and the ink jet recording paper according to the present invention can be manufactured at low cost.

As will be described later, the powder coating sheet according to the present invention can be suitably used, in particular, as an ink-jet recording image-receiving sheet having the above-mentioned resin layer as an ink-jet ink receiving layer.

The powder coating composition used in the present invention contains a resin. This resin forms a resin layer as a receiving layer of the ink-jet ink on the base material, for example, as described above, together with a role as a binder resin to combine various components of the powder coating composition into powder. In addition, when characters and images are recorded by the inkjet ink, a colorant such as a dye or a pigment that forms them is supported to enable recording on an image receiving paper.

Examples of such resins include saturated polyester resins, polyamide resins, (meth) acrylic resins, polyurethane resins, polyvinyl alcohol resins, polyvinyl acetal resins, vinyl chloride resins, vinyl acetate resins, and vinyl chloride / vinyl acetate. Polymeric resin, vinylidene chloride resin, polystyrene resin, styrene resin such as styrene / acrylic copolymer resin, styrene / butadiene copolymer resin, polyethylene resin, ethylene / vinyl acetate copolymer resin, polyethylene resin, ethyl / vinyl acetate Copolymer resins, cellulosic resins, epoxy resins and the like can be mentioned. These resins are used alone or as a mixture of two or more. In the present invention, among these, a saturated polyester resin, a styrene / acrylic copolymer resin, or a mixture thereof is preferably used.

When the powder coated sheet according to the present invention is used for an image-receiving sheet for ink jet recording, the resin in the powder coated composition is not particularly limited as described above. -An acrylic copolymer resin is preferably used.

In the present invention, commercial products can be suitably used as the saturated polyester resin. Such commercial products include, for example, Byron 103, 200, 2
90, 600 (manufactured by Toyobo Co., Ltd.), KA-1038C
(Arakawa Chemical Co., Ltd.), TP-220, 235 (Nippon Synthetic Chemical Industry Co., Ltd.), Diacron ER-101, E
R-501, FC-172, FC-344, FC-71
4 (manufactured by Mitsubishi Rayon Co., Ltd.), Tuffton NE-382,
1110 and 2155 (manufactured by Kao Corporation) and the like.

The styrene / acrylic copolymer resin is a copolymer of styrene and a (meth) acrylic acid ester. Specifically, examples of the (meth) acrylic acid ester include ethyl acrylate and butyl acrylate. , Methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

As such a styrene-acrylic copolymer resin, various commercially available products can be suitably used. Commercial products include, for example, Hymer UNi-3000, TB
-1800, TBH-1500 (Sanyo Chemical Industry Co., Ltd.)
CPR-100, 600B, 200, 300, X
PA4799, 4800 (manufactured by Mitsui Chemicals, Inc.) and the like.

In the present invention, the powder coating composition usually contains a coloring agent. The colorant is preferably white, for example, titanium oxide is preferably used,
It is not limited to this. The colorant gives the substrate the required ground color. The white colorant gives the substrate a white ground color. The coloring agent is usually used in the powder coating composition in an amount of 0.5
To 60% by weight, preferably 5 to 50% by weight.

The powder coating composition may, if necessary, contain an anti-offset agent so that no offset occurs when the composition is heated and melted on the surface of the base material and fixed. Usually, the melting point of the anti-offset agent is 50.
Various waxes in the range of -150 ° C are preferably used. Specifically, for example, paraffin wax,
Examples thereof include polyolefin waxes such as polyethylene and polypropylene, fatty acid metal salts, fatty acid esters, higher fatty acids, and higher alcohols. Such an anti-offset agent is usually added to the powder coating composition in an amount of 0.1 to 20.
%, Preferably in the range of 0.5 to 10% by weight.

The powder coating composition used in the present invention comprises:
Mix with resin, colorant and other additives, usually 1
It is obtained by melt-kneading at a temperature of about 00 to 200 ° C., preferably about 130 to 180 ° C. for several minutes, usually about 3 to 5 minutes, cooling, pulverizing and classifying. The powder coating composition has an average particle size in the range of 0.1 to 30 μm, preferably in the range of 1 to 25 μm, and most preferably in the range of 5 to 20 μm.

According to the present invention, such a powder coating composition is mixed with inorganic fine particles having an average particle diameter in the range of 1 nm to 1 μm, and this mixture (hereinafter referred to as a powder mixture).
Is dry-coated on the surface of the base material, melted by heating, and fixed, whereby the particles of the powder coating composition are coated on the base material with a substantially continuous film composed of the inorganic fine particles. And a separated resin layer can be formed.

In the present invention, the thickness of the resin layer composed of the powder coating composition is usually in the range of 1 to 100 μm,
Preferably, it is in the range of 2 to 80 μm, particularly preferably in the range of 5 to 50 μm.

FIG. 1 schematically shows a cross section of such a powder coating sheet according to the present invention. On the substrate 11,
The individual powder coating composition particles 12 are covered with a film 14 in which inorganic fine particles 13 are substantially connected and are isolated from each other to form a resin layer 15 having an interval or a gap therebetween. Reference numeral 13 is partially exposed on the surface of the resin layer 15.

In order to form a resin layer having such a unique structure, it is necessary to mix inorganic fine particles at a required ratio with respect to the powder coating composition. According to the present invention, the proportion of the inorganic fine particles is usually in the range of 0.5 to 10% by weight, preferably 1 to 9% by weight, in the powder mixture comprising the powder coating composition and the inorganic fine particles. And most preferably in the range of 5 to 8% by weight. However, optimally, it can be experimentally determined according to the respective average particle diameters of the powder coating composition and the inorganic fine particles used. When the blending ratio of the inorganic fine particles is too small, the inorganic fine particles are substantially continuous in a film form, cover the individual powder coating particles, cannot be separated from each other, and cannot be separated. The resulting image is not sufficient in density. On the other hand, if there is too much,
Poor fixability of the receiving layer to the substrate, for example, when the substrate is bent, the receiving layer peels off from the substrate. Furthermore, the proportion of the resin powder coating composition is relatively too small, and the formed image density may be insufficient.

When the average particle diameter of the inorganic fine particles is smaller than 1 nm, even if a relatively large amount of the inorganic fine particles is used, the individual powder coating composition can be formed in a film in which such inorganic fine particles are substantially connected. When the particles cannot be isolated and separated from each other by coating the particles, on the other hand, when the average particle diameter is larger than 1 μm, the powder mixture composed of such inorganic fine particles and the powder coating composition is used. Even after being dry-coated on a material, it is difficult to fix it on a substrate even if it is heated and melted, and peels off from the substrate to cause defects in the resulting coated paper. Therefore, even if such a coated paper is used for an image receiving paper for ink jet recording, a high quality recorded image cannot be obtained.

According to the present invention, the inorganic fine particles are preferably hydrophilic, and among them, hydrophilic inorganic oxide fine particles are preferable. However, a hydrophilic inorganic oxide fine particle and a hydrophobic inorganic oxide fine particle may be used in combination, if necessary, depending on the use and required characteristics of the obtained powder coating paper.

For example, in the case where the powder-coated paper according to the present invention is used as an image-receiving paper for ink-jet recording, if necessary, a hydrophilic property may be adjusted in order to adjust the absorbability of the aqueous ink-jet ink in the ink-receiving layer. Inorganic oxide fine particles and hydrophobic inorganic oxide fine particles can be used in combination.

Such inorganic oxide fine particles can be easily obtained as a commercial product. Commercially available hydrophilic inorganic oxide fine particles include, for example, Aerosil (registered trademark) 50, 9 which is anhydrous silica manufactured by Nippon Aerosil Co., Ltd.
0G, 130,200,200V, 200CF, 200
FAD, 300, 300CF, 380, OX50, TT
600, MOX80, MOX170, COK84, etc.
Aluminum oxide C, titanium dioxide P25, etc., Carplex (registered trademark) silica BS- manufactured by Shionogi & Co., Ltd.
304F, etc., and anhydrous silicas S13, V15, N20, T30, T30 manufactured by Wacker Chemicals East Asia.
40 and the like.

On the other hand, commercially available hydrophobic inorganic oxide fine particles include, for example, Aerosil R972, R972V, and R972, which are anhydrous silica manufactured by Nippon Aerosil Co., Ltd.
CF, R974, R202, R805, R812S, titanium dioxide T805, RX200, RY200, etc., and anhydrous silica H1 manufactured by Wacker Chemicals East Asia
5, H20, H30, H2000, H2000 / 4, H
3004, H2015EP, H2050EP and the like.

As described above, the powder coating paper according to the present invention is coated with particles of the powder coating composition by a substantially continuous film composed of inorganic fine particles, isolated from each other, and separated from each other. Having a resin layer,
As described above, not only the inorganic fine particles are exposed in the form of a film on the surface of the resin layer, but also the particles of the powder coating composition usually have an interval of about 1 μm to about several tens μm. . Some gaps exist between the powder coating composition particles.
Thus, such a powder-coated paper according to the invention is
It can be suitably used as an image receiving paper for ink jet recording.

That is, if the ink jet ink adheres to such an image receiving paper, the aqueous ink is quickly absorbed along the film composed of the inorganic fine particles between the powder coating composition particles, and penetrates into the receiving layer. Along with, the resin layer containing the colorant captures the colorant consisting of the dye or pigment in the ink,
It is possible to obtain a high-quality ink jet recording excellent in absorption and coloring.

Further, according to the present invention, the inorganic fine particles serve to enhance the fluidity of the powder coating composition. That is, it is possible to improve the fluidity when dry-coating the mixture of the powder coating composition and the inorganic fine particles to the base material by, for example, an electrostatic spray method.

In order to form a resin layer comprising the powder coating composition particles as described above on a substrate, a powder mixture of the powder coating composition and inorganic fine particles is dry-coated on the substrate, This is melted by heating and fixed. As described above, the thickness of the resin layer is preferably in the range of 2 to 80 μm.
It is preferably in the range of 0 μm.

In the present invention, in order to dry-coat a powder coating composition containing inorganic fine particles on a substrate, for example, electrostatic coating such as electrostatic spraying or electrostatic immersion, spraying, spraying, etc. Powder coating such as coating method, dispersion method, powder melt lamination method, dusting method, cascade method, magnetic brush developing method,
Electrophotographic methods such as a powder cloud method, an open chamber method, a liquid developing method, a fur developing method, a printing developing method, and a developing method by electrostatic induction can be used.

Among these dry coatings, in the present invention, for example, an electrostatic spray method can be preferably used. This electrostatic spraying method is a kind of powder coating, and specifically, a mixture of a fine powder coating composition and inorganic fine particles (hereinafter referred to as a powder mixture) at the tip of a spray gun is air. And a negative high voltage (for example,
-50 to -90 kV) to apply a negative charge to the powder mixture and, along with a grounded electrode to the back surface of the substrate,
Thus, the negatively charged powder mixture is carried to the substrate and electrostatically deposited by the electric field present between the spray gun and the grounded electrode.

FIG. 2 shows a preferred embodiment of the method of the present invention using such an electrostatic spray method. That is, roll 2
A continuous long substrate (for example, plain paper) 22 rewound from 1 is guided into a booth 24 by a conveyor belt 23, where the powder mixture is electrostatically sprayed, as described later. Is dry-coated, heated and melted by a fixing roll 25, fixed, and then wound around a roll or cut as appropriate. The conveyor belt 23 is grounded on the back side along the base material that the conveyor belt 23 conveys (ie,
(Positive electrode) 26. The powder mixture is stored in storage tank 27
From compressed air to the spray gun 28,
A high negative voltage is applied by a DC power supply 29 to a needle electrode (not shown) incorporated at the tip of the spray gun, and the powder mixture is negatively charged. Thus, the powder mixture is carried to and adheres to the base paper by the electric field present between the spray gun and the electrodes along the substrate on the conveyor belt. In this way, the substrate on which the powder mixture is dry-coated is led to the fixing roll 25, where the powder mixture is heated and melted, fixed on the substrate, and a resin layer is formed. The powder coating paper 30 according to the present invention can be obtained.

Therefore, according to such an electrostatic spraying method, not only a resin layer is formed on the entire surface of the base material, but also, if necessary, only a part of the base material or a required portion can be easily formed. A resin layer can be formed.

[0038]

As described above, the powder coating composition sheet according to the present invention comprises powder coating composition particles having an average particle diameter of 0.1 to 30 μm and inorganic fine particles having an average particle diameter of 1 nm to 1 μm. The substrate has a resin layer of powder coating composition particles that are covered by a substantially continuous film, are isolated from each other, and are separated from each other, with a space between the particles of the individual powder coating composition.

Therefore, such a powder coating sheet can be suitably used as an image receiving sheet for ink jet recording. That is, when the ink-jet ink lands on such an image receiving sheet, the aqueous ink is quickly absorbed along the film made of the inorganic fine particles between the powder coating composition particles, penetrates into the receiving layer, and Since the colorant composed of the dye or pigment therein is easily and quickly captured by the resin layer, it is possible to obtain a high-quality ink jet recording having excellent absorption and coloring properties.

[0040]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples.

Example 1 (Preparation of powder coating composition and powder mixture) Saturated polyester resin (FC-344 manufactured by Mitsubishi Rayon Co., Ltd.) 40
Parts by weight, 30 parts by weight of styrene / acrylic copolymer resin (CPR-200 manufactured by Mitsui Chemicals, Inc.) and 25 white pigments (titanium oxide “Taipek A220” manufactured by Ishihara Sangyo Co., Ltd.)
Parts by weight with a twin-screw kneader at 150 to 160 ° C for 3 to
The mixture was melt-kneaded for 5 minutes. After cooling, the obtained kneaded product was pulverized and classified to obtain a white powder coating composition having an average particle size of 11.0 μm. 95 parts by weight of this white powder coating composition was mixed with 5 parts by weight of hydrophilic anhydrous silica (Aerosil 200 manufactured by Nippon Aerosil Co., Ltd., average particle diameter: 12 nm),
A white powder mixture (5% by weight of anhydrous silica) was used for dry coating by electrostatic spraying.

(Production of Inkjet Recording Image Receiving Paper) The above white powder mixture is adhered to the entire surface of a commercially available plain paper using a commercially available electrostatic spray device, and then heated, melted, and fixed. And a receiving layer having a thickness of 20 μm.

Only the resin layer of the powder-coated paper was embedded in epoxy resin, frozen to prepare a thin film of about 1000 ° C., and then dyed with ruthenium oxide and reinforced with carbon. Was observed. FIG. 3 shows a transmission electron micrograph of a cross section of the resin layer of the powder-coated paper. In the electron micrograph, the white area is the epoxy resin, and the left side is the resin layer. A is a polyester resin,
B is a styrene-acrylic copolymer resin, C is titanium oxide,
D is silica fine particles that are substantially continuous in a strip shape and cover the individual powder coating composition particles and are isolated from each other.

(Inkjet recording) Using a commercially available inkjet printer (manufactured by Epson), inkjet recording was performed on the image receiving paper. As a result, a high-quality recorded image could be obtained quickly.

(Manufacture of image receiving paper having different amounts of silica and performance evaluation) In the same manner as described above, 40 parts by weight of a saturated polyester resin, 30 parts by weight of a styrene / acrylic copolymer resin, 0.3 parts by weight of anhydrous silica, and 1 part by weight Parts, 3 parts by weight, 8 parts by weight, or 12 parts by weight and the white pigment in a total of 1 part by weight.
The white powder mixture for dry coating was prepared such that the amount of anhydrous silica was 0.3%, 1%, 3%, 8% or 12% by weight. In this way, an image receiving paper for ink jet recording was manufactured, and ink jet recording was performed thereon.

When the respective receiving layers for ink jet recording obtained as described above are folded and no change occurs in the receiving layer, the fixing property of the receiving layer to the base material is good (よ い).
When the powder was peeled off from the paper when the paper was folded, the fixability was poor (x).

Further, the density of the image obtained by ink jet recording obtained for each image receiving paper was measured for reflection density using a densitometer (PDA-60 manufactured by Konica). When the value is 6 or more, the image density is sufficient (O),
When at least one of yellow, magenta and cyan was smaller than 1.6, the image density was insufficient (x).

Further, the penetrability of the ink into the receiving layer and the fixability of the ink to the image receiving paper in the ink jet recording were examined as follows. In other words, the ink permeability is good (）) when the inkjet ink has penetrated into the receiving layer to form a clear image, and the ink does not penetrate into the receiving layer. The time when it was set as poor permeability (x).

Table 1 shows the results.

[0050]

[Table 1]

Example 2 (Preparation of powder coating composition and powder mixture) Styrene / acrylic copolymer resin (CPR-20, Mitsui Chemicals, Inc.)
0) 70 parts by weight and 22 parts by weight of a white pigment (titanium oxide “Taipek R550” manufactured by Ishihara Sangyo Co., Ltd.) were melt-kneaded at 150 to 160 ° C. for 3 to 5 minutes using a biaxial melt kneader. After cooling, the obtained kneaded material is pulverized and classified,
A white powder coating composition having an average particle size of 11.0 μm was obtained. 8 parts by weight of hydrophilic anhydrous silica (Aerosil 200CF, manufactured by Nippon Aerosil Co., Ltd., average particle diameter: 12 nm) is mixed with 92 parts by weight of this white powder coating composition, and white for dry coating by electrostatic spraying. A powder mixture was obtained.

Similarly, 70 parts by weight of a styrene-acryl copolymer resin, 3 parts by weight or 5 parts by weight of anhydrous silica, and a white pigment were used so that the total of these was 100 parts by weight. 3% or 5% by weight of silica
A white powder mixture for dry coating was prepared.

(Production of Ink-Jet Recording Paper) The above-mentioned white powder mixture was adhered to the entire surface of a commercially available plain paper using a commercially available electrostatic spray device, and then heated, melted and fixed. Thus, a receiving layer having a thickness of 20 μm was formed.

(Inkjet recording) Inkjet recording was performed on each of the thus-received image receiving papers using a commercially available inkjet printer (manufactured by Epson). A quality recorded image could be obtained.

Further, in the same manner as in Example 1, the fixing property of the receiving layer to the substrate, the image density by ink jet recording, and the permeability of the ink into the receiving layer in ink jet recording were evaluated. All were evaluated as ○.

Example 3 (Preparation of powder coating composition and powder mixture) Styrene / acrylic copolymer resin (CPR-20, Mitsui Chemicals, Inc.)
0) 70 parts by weight and 22 parts by weight of a white pigment (titanium oxide “Taipek R550” manufactured by Ishihara Sangyo Co., Ltd.) were melt-kneaded at 150 to 160 ° C. for 3 to 5 minutes using a biaxial melt kneader. After cooling, the obtained kneaded material is pulverized and classified,
A white powder coating composition having an average particle size of 11.0 μm was obtained. 92 parts by weight of this white powder coating composition was mixed with hydrophilic aluminum oxide (aluminum oxide C manufactured by Nippon Aerosil Co., Ltd.).
8 parts by weight (average particle diameter: 13 nm) were mixed to obtain a white powder mixture for dry coating by an electrostatic spray method.

Similarly, 70 parts by weight of a styrene-acrylic copolymer resin, 3 parts by weight or 5 parts by weight of aluminum oxide, and a white pigment were used so that the total of these was 100 parts by weight. A white powder mixture for dry coating was prepared in which the proportion of aluminum was 3% or 5% by weight.

(Manufacture of Ink-Jet Recording Paper) The above-mentioned white powder mixture was adhered to the entire surface of a commercially available plain paper using a commercially available electrostatic spray device, and then heated, melted and fixed. Thus, a receiving layer having a thickness of 20 μm was formed.

(Inkjet recording) Inkjet recording was performed on each of the thus-received image receiving papers using a commercially available inkjet printer (manufactured by Epson). A quality recorded image could be obtained.

In the same manner as in Example 1, the fixing property of the receiving layer to the substrate, the image density by ink jet recording, and the permeability of the ink into the receiving layer in ink jet recording were evaluated. All were evaluated as ○.

Example 4 (Preparation of powder coating composition and powder mixture) Styrene / acrylic copolymer resin (CPR-20, Mitsui Chemicals, Inc.)
0) 70 parts by weight and 22 parts by weight of a white pigment (titanium oxide “Taipek R550” manufactured by Ishihara Sangyo Co., Ltd.) were melt-kneaded at 150 to 160 ° C. for 3 to 5 minutes using a biaxial melt kneader. After cooling, the obtained kneaded material is pulverized and classified,
A white powder coating composition having an average particle size of 11.0 μm was obtained. To 92 parts by weight of this white powder coating composition, 8 parts by weight of hydrophilic titanium dioxide (Titanium dioxide P25 manufactured by Nippon Aerosil Co., Ltd., average particle diameter: 21 nm) was mixed, and the mixture was dry-coated by electrostatic spraying. A white powder mixture was obtained.

Similarly, 70 parts by weight of a styrene-acrylic copolymer resin, 3 parts by weight or 5 parts by weight of titanium dioxide (P25) and a white pigment were added in a total amount of 100 parts by weight.
A white powder mixture for dry coating was prepared in which the proportion of titanium dioxide (P25) was 3% or 5% by weight by using the mixture so as to be parts by weight.

(Manufacture of Ink-Jet Recording Paper) The white powder mixture was applied to the entire surface of a commercially available plain paper using a commercially available electrostatic sprayer, and then heated, melted and fixed. Thus, a receiving layer having a thickness of 20 μm was formed.

(Inkjet recording) Inkjet recording was performed on each of the thus-received image receiving papers by using a commercially available ink jet printer (manufactured by Epson). A quality recorded image could be obtained.

Further, in the same manner as in Example 1, the fixing property of the receiving layer to the base material, the image density by ink jet recording, and the permeability of the ink into the receiving layer in ink jet recording were evaluated. All were evaluated as ○.

Comparative Example 1 The white powder coating composition of Example 1 was dissolved in methyl ethyl ketone to prepare an oily paint, which was applied on plain paper using a bar coder and dried to obtain an image receiving paper. Was.

Using the same commercially available ink jet printer as in Example 1, ink jet recording was performed on the image receiving paper. However, the ink jet ink was repelled on the receiving layer and no image could be recorded.

[Brief description of the drawings]

FIG. 1 is a schematic view of a cross section of a powder coating sheet according to the present invention.

FIG. 2 shows an example of an apparatus configuration for manufacturing a powder-coated paper according to the present invention.

FIG. 3 is a transmission electron micrograph showing the structure of powder coating composition particles in the resin layer of the powder coating paper according to the present invention.

[Description of Reference Numerals] 11: base material, 12: powder coating composition particles, 13: inorganic fine particles, 14: film made of inorganic fine particles, 15: resin layer, 2
DESCRIPTION OF SYMBOLS 1 ... Roll, 22 ... Base paper, 23 ... Conveying belt, 24 ... Booth, 25 ... Fixing roll, 26 ... Electrode, 27 ... Powder coating composition storage tank, 28 ... Spray gun, 29 ... DC power supply,
30 ... powder paint coated paper.

Claims (14)

[Claims] 1. A resin layer in which powder coating composition particles having an average particle diameter of 0.1 to 30 μm are isolated and separated from each other by a substantially continuous film made of inorganic fine particles having an average particle diameter of 1 nm to 1 μm. A powder-coated sheet characterized by having on a substrate. 2. The powder coating composition according to claim 1, wherein the powder coating composition contains a resin and a colorant. 3. The powder-coated sheet according to claim 1, wherein the amount of the inorganic fine particles is in the range of 0.5 to 10% by weight based on the total amount of the powder coating composition and the inorganic fine particles. 4. The powder coating coated sheet according to claim 1, wherein the inorganic fine particles are hydrophilic anhydrous silica, aluminum oxide or titanium dioxide. 5. The powder coating sheet according to claim 1, wherein the powder coating composition contains a polyester resin, a styrene-acryl copolymer resin or a mixture thereof and a white colorant. 6. The powder coating sheet according to claim 1, wherein the base material is paper. 7. An image-receiving sheet for ink-jet recording, comprising the powder-coated sheet according to any one of claims 1 to 6. 8. A powder coating composition having an average particle diameter of 0.1 to 30 μm is mixed with inorganic fine particles having an average particle diameter of 1 nm to 1 μm, and the resulting mixture is dry-coated on a substrate, heated and melted and fixed. Powder coating composition, wherein the particles of the powder coating composition are separated from each other by a substantially continuous film made of the inorganic fine particles, and a separated resin layer is formed on the base material. Sheet manufacturing method. 9. The method according to claim 8, wherein the powder coating composition contains a resin and a colorant. 10. The method according to claim 8, wherein the amount of the inorganic fine particles is in the range of 0.5 to 10% by weight based on the total amount of the powder coating composition and the inorganic fine particles. 11. The method according to claim 8, wherein the inorganic fine particles are hydrophilic anhydrous silica. 12. The method according to claim 8, wherein the powder coating composition contains a polyester resin, a styrene-acrylic copolymer resin, or a mixture thereof and a white colorant. 13. The method according to claim 8, wherein the base material is paper. 14. A method for producing an ink-jet image-receiving sheet comprising the powder-coated sheet according to any one of claims 8 to 13.