JP2003063128A - Recording medium, method for forming image using the same and method for recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a recording medium for forming a recording image having a drape of a printing paper style, having a high density and an excellent surface glossiness and having a good conveying performance in a recorder, and to provide a method for forming the image using the same and a method for recording. SOLUTION: The recording medium comprises an ink acceptive layer containing inorganic pigment particles including the surface glossiness on a base, a resin layer on a surface opposed to the ink acceptive layer of the base, and a conductive layer between the base and the resin layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium suitable for an ink jet recording system using water-based ink, and
The present invention relates to an image forming method and a recording method using the same.

[0002]

2. Description of the Related Art Inkjet recording systems are designed to eject minute liquid droplets of a recording liquid (recording liquid) such as ink onto various recording mediums such as paper by flying them according to various operating principles.
Characters are recorded. The inkjet recording method is characterized by high speed and low noise, easy multicoloring, great flexibility in recording patterns, and no need for development.It can be applied to printers alone, copiers and word processors. It has been rapidly spread to the output parts of information devices such as facsimiles and plotters. Further, in recent years, high-performance digital cameras, digital video, scanners, etc. are being provided at low cost, and along with the widespread use of personal computers, printers that employ an inkjet recording system to output image information obtained from these are extremely suitable. It is being used. Against this background, it has been required to easily output an image in the inkjet recording system, which is comparable to the multi-color printing of the silver salt type photograph or the plate making system.

In order to meet such requirements, improvements have been made regarding the structure and recording method of the printer itself, such as high speed recording, high definition recording, and full-color recording, while also improving the structure and characteristics of the recording medium. Has been actively studied. Among these, in recent years, a demand for a recording medium having a silver salt photographic-like surface gloss is also increasing.

As a recording medium having a surface glossiness for forming an image by using an ink jet recording system, there is disclosed in Japanese Patent Laid-Open Publication No. Hei 07-2007.
JP-A-149038 discloses an undercoat coating layer containing a pigment, an adhesive and a cationic resin formed by copolymerizing polyalkylene polyamines and dicyandiamide on a base paper, and an ethylenic non-coating layer on the undercoat coating layer. Disclosed is a cast coated paper for inkjet recording, which is formed by laminating a cast coated layer containing a polymer of a monomer having a saturated bond. Further, Japanese Patent Laid-Open No. 11-1060 discloses that
A recording medium having an ink receiving layer containing a non-oriented alumina hydrate on a substrate, or a porous first ink receiving layer containing barium sulfate and a non-oriented alumina hydrate from the substrate side. A recording medium in which a second ink receiving layer containing the same is laminated is disclosed. This recording medium has less resistance to ink permeation, a higher ink absorption speed, and less beading than a recording medium using an alumina hydrate having a hairy bundle (ciliate state) having an orientation. In addition to being prevented, excellent printing quality can be obtained. However, as will be described later, the recording medium having such surface glossiness has a large conveying load on the recording apparatus, and a conveying failure such as double feeding may occur.

[0005]

In recent years, speeding up of recording,
Along with the improvement in the performance of inkjet recording apparatuses such as multicolor printing, more advanced and broader characteristics are required for inkjet recording media. In other words, the characteristics required for inkjet recording media are: high ink absorption capacity, fast ink drying, high dot optical density, no blur around the dots, and dot shape close to a perfect circle. The periphery is smooth, there is no unevenness in light and shade on the solid print part, and the uniformity is excellent. Even if different color inks are printed next to each other, the boundary is clear and bleeding does not occur. It has good properties, light resistance and the like, and the image is stable and does not deteriorate even after long-term storage.

Further, as the texture of the paper, the surface has a high glossiness, the size is such that it can be easily handled, the thickness and the elasticity are good, and the back surface also has an appropriate gloss, so that it is moist. It has the feeling of being

On the other hand, however, the fact that the recording medium has the above-described texture means that most recording devices (contact the recording surface of the laminated body of the recording medium, and the frictional force of one recording medium causes one recording medium to contact one recording medium). An apparatus having a transport mechanism that separates the stack and transports the recording medium to a recording position via a path that bends the recording medium to the recording surface side, and transports the recording medium to the printing position and then performs recording. ), The transport load is increased. That is, a recording medium having a high glossy recording surface tends to have a large frictional force between the papers and a heavy load on paper separation because the recording surface is highly smooth. Therefore, there may occur a problem that defective image formation is likely to occur due to defective transport.

Therefore, an object of the present invention is to form a recording medium satisfying the above-mentioned various required characteristics in a well-balanced manner at the same time, particularly, a recording image having a photographic paper-like texture, high density and excellent surface gloss. In addition, it is an object of the present invention to provide a recording medium having good conveyance performance in a recording apparatus, and an image forming method and a recording method using the recording medium.

[0009]

SUMMARY OF THE INVENTION The inventors of the present invention are required to prepare a recording medium satisfying the above required performances.
(i) having a layer on the substrate which forms a recording surface mainly composed of an inorganic pigment having a surface gloss, (ii) having a resin layer on the opposite side of the recording surface of the substrate, (iii) It was found that it is essential to have a conductive layer between the resin layer and the base material, and the present invention has been completed.

That is, the above object is achieved by the present invention described below. (1) A recording medium having an ink receiving layer containing inorganic pigment particles having surface gloss on a base material, and further having a resin layer on a surface of the base material facing the ink receiving layer, A recording medium having a conductive layer between the resin layer and the resin layer. (2) The recording medium according to (1), wherein the volume resistivity of the conductive layer is 10 ¹² Ω · cm or less. (3) An image forming method in which a small ink droplet is ejected from an orifice of a recording head in accordance with a recording signal and adheres to the recording medium of (1) or (2) to perform recording. (4) An image forming method in which droplets of cyan, magenta, yellow, and black inks are ejected from an orifice of a recording head in accordance with a recording signal and are attached to the recording medium of (1) or (2) to perform recording. (5) A recording position is brought into contact with the recording surface of the laminated body of the recording medium, separates one recording medium from the laminated body by the frictional force, and passes through a path for bending the separated recording medium to the recording surface side. A recording method using a recording device for performing recording after being conveyed to
Alternatively, the recording method which is the recording medium of (2). (6) The recording method according to (5), wherein recording is performed by the image forming method according to (3) or (4).

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The recording medium of the present invention has an ink receiving layer containing inorganic pigment particles having surface gloss on a substrate, and further has a resin layer on the surface of the substrate facing the ink receiving layer. And has a conductive layer between the base material and the resin layer. The volume resistivity of this conductive layer is 10 ¹² Ω · cm or less.

The ink-receptive layer having surface gloss formed on the substrate is mainly for forming an excellent recorded image. The surface side on which the ink receiving layer is formed is the recording surface, and the surface side on which the conductive layer and the resin layer are formed is the back surface.

The resin layer formed on the surface of the base material facing the ink receiving layer imparts a texture such as a glossy feeling to the back surface of the recording medium and, at the same time, is effective in suppressing curling of the recording medium. Furthermore, by providing the resin layer, it is possible to reduce the frictional force between the recording media in the stacked state and improve the performance of the recording media to be conveyed.

However, a recording medium in which only a resin layer is provided on the back surface of a surface glossy recording medium composed of a conventionally known base material and an ink receiving layer has an excellent conveying performance with few paper feeding defects in a normal environment. However, double feeding may occur in some special environments, especially in low temperature and low humidity environments. By providing the conductive layer between the base material and the resin layer, this problem is solved, and excellent feeding performance with few paper feed defects can be obtained even in an environment of low temperature and low humidity. Although the mechanism itself is unknown, the cause of double feeding is an electrostatic factor, and it is presumed that the electrostatic charge is prevented by providing a conductive layer. Providing a conductive layer is one of the important features of the present invention.

The present invention will be described in detail below.

FIG. 1 shows a schematic sectional view of the recording medium of the present invention. In the recording medium of the present invention shown in FIG. 1, an ink receiving layer 2 having surface gloss is formed on one surface of a substrate 1, and a conductive layer 3 and a resin layer 4 are sequentially formed on the opposite surface. In addition, what is shown in FIG. 1 is an example, and for example, two or more ink receiving layers may be formed.

Substrate The substrate 1 is a support, and usually paper is used. For example, as the base material 1, a chemical pulp represented by LBKP, NBKP, etc. is mainly used, and a sizing agent, a filler, and other papermaking auxiliaries are used as necessary, and a paper made by a conventional method can be used.

Ink Receptive Layer The ink receptive layer 2 contains inorganic pigment particles having a surface gloss, and any conventionally known one can be used. The ink receiving layer is mainly composed mainly of an inorganic pigment and a binder.

Examples of the inorganic pigments used in the present invention include silica, alumina, aluminum hydroxide,
Aluminum silicate, magnesium silicate, basic magnesium carbonate, talc, clay, hydrotalcite,
Examples thereof include calcium carbonate, titanium oxide and zinc oxide. The pigments may be used alone or in combination of two or more.
Above all, it is preferable to use one or more of silica, alumina, hydrated alumina, and basic magnesium carbonate because they have excellent ink absorption performance.

Further, plastic pigments such as polyethylene, polystyrene and polyacrylate may be contained within a range not impairing the above-mentioned purpose.

The average particle size of the inorganic pigment particles is 5 nm because it forms a porous structure that can obtain sufficient ink absorbency.
It is preferably not less than 20 μm because it has excellent surface gloss.

Examples of the binder used in the present invention include polyvinyl alcohol, starch, cationized starch, casein, gelatin, acrylic resin,
Sodium alginate, polyvinylpyrrolidone, carboxymethylcellulose, water-soluble resins such as hydroxyethyl cellulose, acrylic polymer latex such as polymers or copolymers of acrylic acid ester or methacrylic acid ester, carboxyl modified conjugated diene copolymer latex, Examples thereof include vinyl copolymer latex such as ethylene-vinyl acetate copolymer. The binder may be used alone or in combination of two or more. Above all, it is preferable to use polyvinyl alcohol or vinyl-based copolymer latex because the binding strength of the above-mentioned inorganic pigment is excellent.

The ratio of the inorganic pigment to the binder in the ink receiving layer is such that the content of the pigment is 1/2 of that of the binder because a recorded image having excellent ink absorbency and high optical density can be obtained.
It is preferable that the amount is more than the mass times, and since the mechanical strength of the ink receiving layer is high and sufficient abrasion resistance can be obtained,
The content of the pigment is preferably 10 times or less the mass of the binder.

In the present invention, the ink receiving layer may optionally contain a cross-linking agent such as melamine resin, glyoxal and isocyanate, a cationic substance as a dye fixing agent, a surfactant, a defoaming agent, and an antioxidant. Agents, optical brighteners, ultraviolet absorbers, dispersants, viscosity modifiers, pH modifiers,
It may contain an antifungal agent, a plasticizer and the like. The content of these may be appropriately determined, but is usually preferably 3% by mass or less.

The ink receiving layer formed of the above materials does not necessarily have to have a single layer structure, but may have a two or more layer structure in which the functions are separated according to need.

The thickness of the ink receiving layer is preferably 10 μm or more in total because good ink absorbency can be obtained. In addition, the thickness of the ink receiving layer is excellent in mechanical strength of the ink receiving layer, and the occurrence of curling is small,
The total thickness is preferably 50 μm or less.

To form the ink receiving layer, first, the above-mentioned inorganic pigment and binder are dissolved or dispersed in a suitable organic solvent such as alcohol or water together with other additives, if necessary, to prepare a coating solution. Adjust. The concentration of the solid content of the coating liquid is usually about 1 to 50% by mass. And
The obtained coating liquid is used as a substrate by, for example, a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a bar coater method, a size press method, a spray coat method, a gravure coater method, or a curtain coater method. It is coated on the surface and dried by a conventional method to form an ink receiving layer. To improve the gloss of the surface,
A casting method may be used in which the ink receiving layer (surface layer) is pressed against a mirror-finished hot metal drum and dried while the ink receiving layer (surface layer) is in a wet state. Known methods such as a wet method, a rewet method, and a gelation method can be used.

Although the conductive layer and the resin layer are usually formed after forming the ink receiving layer, the ink receiving layer may be formed after forming the conductive layer and the resin layer.

Further, in order to obtain the texture of a silver salt photograph, the 75 ° specular gloss of the surface of the recording medium on the ink receiving layer side is 45.
% Or more, particularly preferably 65% or more. In addition,
Here, the 75 ° surface glossiness means a reference surface (a glass having a refractive index of 1.567) of reflected light at an equal angle (reflecting angle of 75 °) with respect to incident light having an incident angle of 75 °, that is, specular reflected light. Plane) of the light reflected under the same conditions.

Resin Layer The resin layer 4 is mainly composed of polyolefin such as polyethylene, polypropylene and polyisobutylene, polyvinyl chloride, polyvinyl acetate, polystyrene, polyacrylate, polyamide, polyimide, polyester and cellulose resin. Since the resin layer 4 does not adversely affect the glossy surface (scratches, blocking, discoloration, etc.) when a plurality of recording media are stacked, it is particularly preferable to mainly use polyolefin.

The average degree of polymerization of the resin used is preferably 10,000 or more from the viewpoint of the strength of the resin layer.

Further, in the present invention, the resin layer may contain inorganic pigment particles, other additives and the like, if necessary.
The content of these may be appropriately determined, but is usually preferably 50% by mass or less.

The thickness of the resin layer is 10 μm or more because the waviness and curl of the recording medium to be formed are sufficiently suppressed.
It is particularly preferably 15 μm or more. In addition, the thickness of the resin layer is 30 μm because the contraction stress on the back surface side is small, and the conveyance failure is unlikely to occur even in the recording apparatus having the conveyance path for bending the recording medium to the printing surface side as described above.
It is particularly preferable that the thickness is 20 μm or less.

The resin layer may be formed on the conductive layer after forming the ink receiving layer and the conductive layer, which will be described later, by a method such as laminating or extrusion coating in a state in which the above-mentioned material such as polyolefin resin is melted by heat. . Also, on the conductive layer,
Materials such as the above-mentioned polyolefin resin are water, alcohol,
It may be formed by applying a coating solution obtained by dissolving or dispersing in a solvent such as ethyl ether, methyl ethyl ketone, dimethylformamide, formic acid, etc., and drying. The concentration of the solid content of the coating liquid is usually about 1 to 50% by mass. Of course, if the ink receiving layer can be formed, the conductive layer and the resin layer may be formed first, and then the ink receiving layer may be formed.

Conductive Layer In the present invention, a conductive layer is provided between the base material and the resin layer. The volume resistivity of the conductive layer is 10 ¹² Ω · cm or less, and extremely excellent transport performance can be obtained even in an environment of low temperature and low humidity. Therefore, it is particularly preferably 10 ¹¹ Ω · cm or less. The lower limit of the volume resistivity of the conductive layer is not particularly specified, but is usually 1
0 ⁷ Ω · cm or more.

The conductive layer 3 is not particularly limited as long as it has conductivity and prevents the surface of the resin layer 4 from being charged.
For example, a conductive resin layer or a metal layer can be used.

The conductive resin layer may be composed of a resin having conductivity, and a water-soluble inorganic salt or various organic antistatic agents may be dissolved or dispersed in the resin. It may be made up of a material.

As the resin itself having conductivity,
For example, a homopolymer of a monomer having a tertiary amino group or a quaternary ammonium salt monomer, or a copolymer with another copolymerizable monomer can be used.

When a water-soluble inorganic salt or various organic antistatic agents are added, as the resin, those exemplified as the binder in the above-mentioned ink receiving layer can be used. Further, as the water-soluble inorganic salt, for example,
Sodium chloride, magnesium chloride, potassium chloride and the like can be used. Examples of the organic antistatic agent include anionic antistatic agents such as alkyl sulfonate, alkylbenzene sulfonate, and alkyl sulfate, quaternary ammonium chloride, quaternary ammonium sulfate, and quaternary ammonium nitrate. And the like, and amphoteric antistatic agents such as alkyl betaine type and alkyl imidazoline type can be used.

As the conductive resin, resin such as carbon black, graphite, aluminum, copper, tin,
Various conductive metals or alloys such as stainless steel, tin oxide, zinc oxide, indium oxide, titanium oxide, tin oxide-
Various conductive metal oxides such as antimony oxide solid solution and tin oxide-indium oxide solid solution, and those to which a conductive agent such as fine powder such as an insulating material coated with these conductive materials is added can also be used.

After forming the ink receiving layer, the conductive resin layer is coated with a material such as resin on the surface (back surface) of the base material facing the ink receiving layer, such as water, alcohol, ethyl ether, methyl ethyl ketone, dimethylformamide, formic acid and the like. It may be formed by coating a coating solution obtained by dissolving or dispersing in a solvent of 1) and drying, or by applying a material such as a resin in a state of being heat melted by a method such as laminating or extrusion coating. You may. The concentration of the solid content of the coating liquid is usually 1 to 50.
Set to about mass%. Of course, if the ink receiving layer can be formed, the conductive layer and the resin layer may be formed first, and then the ink receiving layer may be formed.

As the metal layer (metal thin film layer), for example,
Metals such as iron, copper, aluminum and nickel, or alloys thereof are mentioned. The metal layer may contain a metal in the form of a compound containing oxygen, nitrogen, carbon or the like as long as sufficient conductivity is obtained.

The metal layer may be adhered to the back surface of the base material via an adhesive layer after the metal thin film is formed in advance, or may be directly formed on the back surface of the base material by a method such as vapor deposition. Good.

In any of the embodiments, the conductive layer is not particularly limited as long as it is formed as a uniform layer, but the thickness of the conductive layer is 0 because the effect of the present invention can be sufficiently obtained. It is preferably 0.001 μm or more, particularly 0.01 μm or more, and from the viewpoint of productivity, 20 μm or less,
It is particularly preferably 10 μm or less.

Image Forming Method, Recording Method In the image forming method of the present invention, small droplets of ink, preferably cyan, magenta, yellow, and black ink droplets are ejected from the orifices of the recording head in accordance with a recording signal, Recording is carried out by adhering to the recording medium of the present invention.

In the recording method of the present invention, the recording medium is brought into contact with the recording surface of the laminated body and the frictional force separates one recording medium from the laminated body, and the separated recording medium is bent toward the recording surface side. Recording is performed by the above-described image forming method of the present invention by a recording device that performs recording after being conveyed to a recording position via a path.

The ink, which is the recording liquid used in the present invention, contains a dye for forming an image and a liquid medium for dissolving or decomposing the dye as essential components, and if necessary, various dispersants and interfaces. It is adjusted by adding an activator, a viscosity adjusting agent, a specific resistance adjusting agent, a pH adjusting agent, an antifungal agent, a stabilizer for dissolving (or dispersing) a recording agent, and the like.

Examples of the recording agent used in the ink include direct dyes, acid dyes, basic dyes, reactive dyes, food dyes, disperse dyes, oil dyes and various pigments, and known ones are used without particular limitation. can do.

The content of such a dye is determined depending on the type of the liquid medium component, the characteristics required for the ink, etc., but is generally about 0.1 to 20 mass% in the conventional ink. Therefore, the ratio may be the same in the present invention.

The liquid medium used for the ink is
Examples thereof include water, methyl alcohol, ethyl alcohol, isopropyl alcohol, ethylene glycol, diethylene glycol, glycerin, N-methyl-2-pyrrolidone and the like.

The ink jet recording method used in the present invention may be any method as long as it can effectively separate ink from the nozzle to apply the ink to the recording medium as a range, but in particular, In the method described in Japanese Laid-Open Patent Publication No. 54-59936, the ink-jet method in which the ink subjected to the action of thermal energy causes a rapid volume change and the ink is ejected from the nozzle by the action force due to this state change is effectively used. can do.

[0052]

The present invention will be described in more detail with reference to the following examples. In the examples, “part” or “%” is based on mass unless otherwise specified.

Example 1 A coating liquid (1) for forming an ink receiving layer having the following composition was prepared and dried on a base paper for coating to a dry coating amount of 20 g / m ² using a wire bar. After being applied so as to form the first layer, the first layer was formed by drying at 100 ° C. for 5 minutes. The thickness of the ink receiving layer (first layer) was 26 μm.

Coating Liquid (1) Composition Alumina (Sumitomo Chemical Co., Ltd., trade name: AKP-G030) 70 parts Basic magnesium carbonate (Tokuyama Soda Co., Ltd.) 30 parts Polyvinyl alcohol (Kuraray Co., trade name: PVA-117) 15 Part Copolymer of monoallylamine / dimethylamine hydrochloride (Nitto Boseki, trade name: PAA-D11-HCl) 10 parts Water 975 parts

A coating liquid (2) for forming an ink receiving layer having the following composition was prepared, and a dry coating amount was 8 g / m ² on the first layer of the ink receiving layer using a wire bar. After coating in this manner, while the coating was in a wet state, it was pressed against a stainless steel roll heated to 80 ° C. and dried to form a second layer. The thickness of this ink receiving layer (second layer) is 11 μm.
It was m.

Coating liquid (2) Composition Polyvinyl alcohol (Kuraray, trade name: PVA-117) 5 parts Alumina sol (Catalyst Kasei, trade name: AS-3) (solid content) 50 parts Calcium stearate (solid content) 2 parts water 443 parts

A conductive layer-forming coating solution having the following composition was prepared, and the dry thickness was 5 μm on the back surface (the surface facing the ink receiving layer) of the base material of the coated paper formed as described above. After coating with the bar coater method,
After drying for a minute, a conductive layer was formed. The volume resistivity of the formed conductive layer was 3 × 10 ⁹ Ω · cm.

Coating liquid composition for conductive layer formation Polyvinyl alcohol (Kuraray, trade name: PVA-117) 15 parts Sodium chloride 0.5 parts Water 85 parts

Then, a low density polyethylene resin (trade name: Chemipearl, manufactured by Mitsui Petrochemical Industry Co., Ltd.), which was heated and melted as a resin layer, was laminated on the conductive layer to a thickness of 15 μm to prepare a recording medium of the present invention. .

The 75 ° specular gloss of the ink receiving layer side surface of the recording medium thus prepared was 70%.

Comparative Example 1 A recording medium was prepared in the same manner as in Example 1 except that the conductive layer was not formed.

(Evaluation) The recording mediums of Example 1 and Comparative Example 1 prepared as described above were prepared as A4 size sheet sheets. Then, the recording medium comes into contact with the recording surface of the laminated body, the frictional force separates one recording medium from the laminated body, and the separated recording medium is bent to the recording surface side to a recording position. An ink jet recording apparatus having a means for transporting and ejecting the ink by foaming the ink by thermal energy was used to stack ten recording media on a paper feed tray of the recording apparatus to continuously perform recording. Recording was performed in an environment of low temperature and low humidity of 15 ° C. and 10% RH.

As a result, the recording medium of Example 1 provided with the conductive layer was normally recorded, but the recording medium of Comparative Example 1 not provided with the conductive layer was overlaid with paper from the fifth recording onward. Delivery has occurred.

[0064]

As described above, according to the present invention,
A recording medium having a print paper-like texture, high density, and excellent surface glossiness, and having good conveyance performance in a recording apparatus, and an image forming method and recording method using the same Can be provided.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a recording medium of the present invention.

[Explanation of symbols]

1 base material 2 Ink receiving layer 3 Conductive layer 4 resin layers

Claims (9)

[Claims] 1. A recording medium having an ink receiving layer containing inorganic pigment particles having surface gloss on a base material, and further having a resin layer on a surface of the base material facing the ink receiving layer.
A recording medium having a conductive layer between the base material and the resin layer. 2. The volume resistivity of the conductive layer is 10 ¹² Ω · cm.
The recording medium according to claim 1, which is as follows. 3. The recording medium according to claim 1, wherein the conductive layer is a conductive resin layer or a metal layer. 4. The recording medium according to claim 1, wherein the resin layer has a thickness of 10 to 30 μm. 5. The ink receiving layer side surface of the recording medium is at 75 °.
The recording medium according to claim 1, which has a specular gloss of 45% or more. 6. An image forming method in which a droplet of ink is ejected from an orifice of a recording head in accordance with a recording signal and adhered to the recording medium according to claim 1 to perform recording. 7. A recording is carried out by ejecting small droplets of cyan, magenta, yellow and black inks from an orifice of a recording head in accordance with a recording signal and adhering them to the recording medium according to claim 1. Image forming method. 8. A recording medium is brought into contact with a recording surface of the laminated body, and the frictional force separates one recording medium from the laminated body, and the separated recording medium is passed through a path for bending to the recording surface side. A recording method using a recording device for recording after being conveyed to a recording position, wherein the recording medium is the recording medium according to any one of claims 1 to 5. 9. The recording method according to claim 8, wherein recording is performed by the image forming method according to claim 6.