JP2005070753A - Paper, method for manufacturing same, support for image recording material, and image recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide paper having high surface smoothness and extremely outstanding glossiness, a method for manufacturing the same, a support for an image recording medium, and an image recording medium. <P>SOLUTION: The paper has base paper and a polymer-containing layer on the surface on the side to be provided with at least an image recording layer of the base paper and is formed by subjecting the paper to pressure drying treatment. The form that the base paper is manufactured by subjecting wet paper to pressure drying treatment, the form that the polymer-containing layer contains at least either of a water-soluble polymer and water-dispersible emulsion and the form that the polymer-containing layer contains a pigment are preferable. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to paper having high surface smoothness and extremely excellent gloss, a method for producing the same, a support for image recording material, and an image recording material.

  2. Description of the Related Art Conventionally, paper that has been efficiently made at high speed is dried while being contracted freely in the transverse direction while receiving tension in the longitudinal direction (paper making direction) between a number of cylindrical dryer groups. Therefore, when the paper is subjected to a change in humidity, it tends to expand and contract greatly in the lateral direction. For this reason, when a photograph or the like is recorded using the paper as a support, there is a problem that curling becomes large and a high-quality image cannot be formed.

In order to solve the above-mentioned problems, paper is dried after drying by using a so-called Yankee machine that can regulate drying shrinkage in both the vertical and horizontal directions without being subjected to vertical tension during drying. An electrophotographic transfer paper having a small shrinkage ratio, excellent smoothness, and small curl even when subjected to humidity change has been proposed (see Patent Document 1).
However, in this case, when making paper using the Yankee machine, in general, many paper making conditions such as freeness of pulp paper stock and paper making speed are limited, and production restrictions become very large. There's a problem.

  Further, it is described that the press drying treatment is expected to increase the strength, elastic modulus, density, and the like of the paper, and development is being advanced (see Non-Patent Document 1). In addition, there has been proposed a web pressure drying apparatus in which the fiber web is heated and dried by a press drying process and is less restricted when used as a production line (see Patent Documents 2 to 3). However, the non-patent document 1 does not disclose or suggest any specific conditions for the press dry process. Patent Documents 2 and 3 only describe a press-drying apparatus, and no study is made on the relationship between the conditions for the press-drying process and the support for the image recording material.

On the other hand, base paper, synthetic paper, synthetic resin sheet, coated paper, laminated paper, and the like are used as the support for the image recording material, and among these, coated paper and laminated paper are preferable.
Examples of the method for producing the coated paper and the laminated paper include a solvent coating method in which a thermoplastic resin is dissolved in an organic solvent and applied to the base paper, and an aqueous coating in which the thermoplastic resin is applied to the base paper in the form of latex or aqueous solution (varnish). Method, thermoplastic resin dry lamination (bonding) method, melt extrusion coating method, and the like.

  However, since the solvent coating method uses a harmful organic solvent, it has a problem of adversely affecting the environment. Further, in the aqueous coating method, when applying latex or an aqueous solution (varnish) to the base paper, the so-called “return” that the base paper swells with water and loses smoothness occurs, There is a problem that it cannot be applied to a resin that is difficult to be made into latex or an aqueous solution.

  Accordingly, a support for an image recording material and an image recording material having high surface smoothness and extremely excellent gloss have not yet been provided, and the present situation is that further improvement and development are desired.

JP-A-1-292354 (Patent No. 2739160) Special Table 2000-500536 JP 7-91829 A (Patent No. 3041754) Taku Kadoya et al. “Paper Science” Chugai Industry Research Committee, June 30, 1982, p. 174-177

  The present invention aims to solve the above-described problems and solve the following problems. That is, the present invention provides a paper having a high surface smoothness and extremely excellent gloss and a method for producing the same, as well as an electrophotographic material, a heat sensitive material, an ink jet recording material, a sublimation transfer material, a silver salt photographic material, a thermal transfer material, and the like. It is an object of the present invention to provide a suitable support for an image recording material and an image recording material.

Means for solving the problems are as follows. That is,
<1> Paper having a base paper and a polymer-containing layer on at least a surface of the base paper on which an image recording layer is provided, wherein the paper is pressure-dried.
<2> The paper according to <1>, wherein the base paper is a base paper obtained by pressure-drying wet paper.
<3> The paper according to any one of <1> to <2>, wherein the polymer-containing layer contains at least one of a water-soluble polymer and a water-dispersible polymer emulsion.
<4> The paper according to any one of <1> to <3>, wherein the polymer-containing layer contains a pigment.
<5> including a polymer-containing layer forming step of forming a polymer-containing layer on at least an image recording layer side of the base paper, and a pressure-drying processing step of pressure-drying the base paper having the polymer-containing layer. Is a method for producing paper.
<6> The paper manufacturing method according to <5>, wherein a calendar process is performed after the pressure drying process.
<7> The method for producing a paper according to any one of <5> to <6>, wherein a polymer-containing layer forming step is performed on a base paper obtained by subjecting wet paper to pressure drying.
<8> The method for producing a paper according to any one of <5> to <7>, wherein the polymer-containing layer is dried until the water content in the polymer-containing layer becomes 5 to 30% and then subjected to pressure drying treatment.
<9> The paper manufacturing method according to any one of <5> to <8>, wherein the press pressure in the pressure drying treatment is 0.05 to 0.5 MPa.
<10> An image recording material support comprising the paper according to any one of <1> to <4>.
<11> An image recording material having a support and at least an image recording layer on the support, wherein the support is the support for an image recording material according to <10>. Recording material.
<12> The image recording material according to <11>, wherein the image recording material is selected from electrophotographic materials, heat-sensitive materials, inkjet recording materials, sublimation transfer materials, silver salt photographic materials, and thermal transfer materials.

  The paper of the present invention is a paper having a base paper and a polymer-containing layer on at least the surface on which the image recording layer is provided. The paper is subjected to a pressure drying treatment. In the paper of the present invention, the base paper subjected to the polymer adhesion treatment is subjected to a press-drying treatment so that the surface smoothness is high and the gloss is extremely excellent.

  The paper manufacturing method of the present invention includes a polymer-containing layer forming step and a pressure drying treatment step. In the polymer-containing layer forming step, a polymer-containing layer is formed on the surface of the base paper on which at least the image recording layer is provided. In the pressure drying treatment step, the base paper having the polymer-containing layer is subjected to a pressure drying treatment. As a result, a paper having high surface smoothness and extremely excellent gloss can be obtained.

  The support for image recording material of the present invention comprises the paper of the present invention. The image recording material of the present invention has the support for image recording material of the present invention and an image recording layer on the support. Since the image recording material of the present invention has high surface smoothness and extremely excellent gloss, it is an electrophotographic image receiving material, a heat-sensitive color developing material, a sublimation transfer image receiving material, a silver salt photographic light receiving material, and a thermal transfer image receiving image. It is suitably used as at least one recording material selected from materials.

  According to the present invention, various conventional problems can be solved, excellent in smoothness and gloss, and various types such as an electrophotographic material, a heat sensitive material, an ink jet recording material, a sublimation transfer material, a silver salt photographic material, and a thermal transfer material. A support for an image recording material suitable as an image recording material can be provided.

(paper)
The paper of the present invention has a base paper and a polymer-containing layer on at least the surface on which the image recording layer is provided, and further has other layers as necessary.
In the present invention, as the base paper, a base paper obtained by pressure-drying wet paper is used.

-Base paper-
The base paper is not particularly limited and may be appropriately selected depending on the intended purpose. Specifically, it is a high-quality paper, for example, “Photographic Engineering Basics—Silver Salt Photography” edited by the Japan Photography Society, Papers described on pages 223 to 224 of the company Corona (Showa 54) are preferred.

  The base paper is not particularly limited as long as it is a known material used for a support, and can be appropriately selected from various materials according to the purpose. For example, natural pulp such as conifers and hardwoods, Examples include a mixture of pulp and synthetic pulp.

The pulp that can be used as the raw material of the base paper is hardwood bleached kraft pulp (LBKP) from the viewpoint of improving the surface smoothness, rigidity and dimensional stability (curling property) of the base paper to a balanced and sufficient level at the same time. Although desirable, softwood bleached kraft pulp (NBKP), hardwood sulfite pulp (LBSP) and the like can also be used.
A beater, refiner, or the like can be used to beat the pulp.
The Canadian standard freeness of the pulp can control the shrinkage of the paper in the paper making process, so 200-440 ml C.I. S. F. Is more preferred, 250-380 ml C.I. S. F. Is more preferable.
In the pulp slurry obtained after beating the pulp (hereinafter sometimes referred to as “pulp stock”), various additives such as a filler, a dry paper strength enhancer, a sizing agent, A wet paper strength enhancer, a fixing agent, a pH adjuster, and other chemicals are added.

Examples of the filler include calcium carbonate, clay, kaolin, white clay, talc, titanium oxide, diatomaceous earth, barium sulfate, aluminum hydroxide, and magnesium hydroxide.
Examples of the dry paper strength enhancer include cationized starch, cationized polyacrylamide, anionized polyacrylamide, amphoteric polyacrylamide, and carboxy-modified polyvinyl alcohol.
Examples of the sizing agent include fatty acid salts, rosin derivatives such as rosin and maleated rosin, paraffin wax and the like, and further higher fatty acids such as alkyl ketene dimer, alkenyl succinic anhydride (ASA), and epoxidized fatty acid amide. And the like.
Examples of the wet paper strength enhancer include polyamine polyamide epichlorohydrin, melamine resin, urea resin, and epoxidized polyamide resin.
Examples of the fixing agent include polyvalent metal salts such as aluminum sulfate and aluminum chloride, and cationic polymers such as cationized starch.
Examples of the pH adjuster include caustic soda and sodium carbonate.
As said other chemical | medical agent, an antifoamer, dye, a slime control agent, a fluorescent whitening agent, etc. are mentioned, for example.
Furthermore, a softening agent etc. can also be added as needed. As the softening agent, for example, those described in New Handbook for Paper Processing (edited by Paper Medicine Time), pages 554 to 555 (issued in 1980) can be used.
These various additives may be used alone or in combination of two or more. Moreover, there is no restriction | limiting in particular in the addition amount in these pulp paper materials, such as these various additives, It can select suitably according to the objective, 0.1-1.0 mass% is preferable normally.

If necessary, the pulp slurry may further include a paper machine such as a manual paper machine, a long paper machine, a round paper machine, a twin wire machine, or a combination machine. It is used to make paper and then dried to produce a base paper. Further, if desired, the surface sizing treatment can be performed either before or after the drying.
The treatment liquid used for the surface sizing treatment is not particularly limited and may be appropriately selected depending on the intended purpose. May be included.
Examples of the water-soluble polymer compound include cationized starch, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate, gelatin, casein, sodium polyacrylate, styrene-maleic anhydride copolymer sodium. Salt, sodium polystyrene sulfonate, and the like.

Examples of the water-resistant substance include latex / emulsions such as styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, polyethylene, vinylidene chloride copolymer, and polyamide polyamine epichlorohydrin.
Examples of the pigment include calcium carbonate, clay, kaolin, talc, barium sulfate, and titanium oxide.

  The base paper has a longitudinal Young's modulus (Ea) and a transverse Young's modulus (Eb) ratio (Ea / Eb) of 1.5 to 2.0 in terms of improving rigidity and dimensional stability (curling property). It is preferable that it exists in the range. When the Ea / Eb value is less than 1.5 or more than 2.0, the recording material is liable to deteriorate in rigidity and curl property, which is not preferable.

In general, it is known that the “strain” of paper differs based on the difference in the mode of beating, and after the beating, the elasticity (rate) of the paper made by papermaking represents the degree of “strain” of the paper. Can be used as an additional factor. In particular, the elastic modulus of paper is measured by measuring the speed of sound propagating through the paper, using the relationship between the dynamic elastic modulus and density, which indicates the physical properties of the viscoelastic material of the paper, and using an ultrasonic vibration element. Can be obtained from the following equation.
E = ρc ² (1-n ² )
However, in the said numerical formula, E means a dynamic elastic modulus. ρ means density. c means the speed of sound in the paper. n means Poisson's ratio.

In the case of normal paper, since n = about 0.2, even if it is calculated by the following formula, it can be calculated without much difference.
E = ρc ²
That is, if the density and sound speed of paper can be measured, the elastic modulus can be easily obtained. In the above equation, when measuring the speed of sound, various known devices such as Sonic Tester SST-110 (manufactured by Nomura Corporation) can be used.

  In order to impart a desired centerline average roughness to the surface of the base paper, for example, as described in JP-A-58-68037, a fiber length distribution (for example, a 24 mesh screen residue and , 42 mesh screen residue is, for example, preferably 20 to 45 mass% and 24 mesh screen residue is 5 mass% or less). Further, the center line average roughness can be adjusted by applying heat and pressure to the surface with a machine calendar, a super calendar, or the like.

There is no restriction | limiting in particular in the thickness of the said base paper, According to the objective, it can select suitably, Usually, 30-500 micrometers is preferable, 50-300 micrometers is more preferable, 100-250 micrometers is still more preferable. The basis weight of the raw paper is not particularly limited and may be suitably selected according to the purpose, for example, preferably ^{50~250g / m 2, 100~200g / m} 2 is more preferable.

-Polymer-containing layer-
The polymer-containing layer is provided on at least the surface of the base paper on which the image recording layer is provided, the polymer-containing layer contains at least one of a water-soluble polymer and a water-dispersible polymer emulsion, a pigment, and further, if necessary Accordingly, it contains other components.

  Examples of the water-soluble polymer include cationized starch, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate, gelatin, casein, sodium polyacrylate, styrene-maleic anhydride copolymer sodium salt, Examples thereof include sodium polystyrene sulfonate. These may be used individually by 1 type and may use 2 or more types together.

  As the water-dispersible polymer emulsion, either an emulsion or a latex is suitable. Examples of the emulsion include hydrocarbon waxes such as paraffin wax and microcrystalline wax; oxygen-containing waxes such as carnauba wax and montan wax oxidized paraffin; petroleum resins, coumarone indene resins, terpene resins, and carboxylic acid adducts thereof. And other emulsions such as alkyl ketene dimers and epoxidized fatty acid amides. These may be used individually by 1 type and may use 2 or more types together. Among these, a soap-free emulsion is particularly preferable.

As the soap-free emulsion, either an acrylic soap-free emulsion or a polyolefin soap-free emulsion is suitable.
Examples of the acrylic soap-free emulsion include acrylic acid ester homopolymers, copolymers of acrylic acid esters and methacrylic acid esters, vinyl acetate, styrene, acrylonitrile, acrylic acid, and the like. Examples of the polyolefin soap-free emulsion include ethylene vinyl acetate copolymer emulsion, ethylene acrylic acid copolymer, ionomer and the like.

  The aqueous medium is preferably composed mainly of water or a water-soluble organic solvent added to water. Examples of the water-soluble organic solvent include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (average molecular weight of about 190 to 400), glycerin, alkyl ethers of the above glycols, and N-methylpyrrolidone. 1,3-dimethylimidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethyl sulfoxide, diethanolamine, triethanolamine, ethanol, isopropanol, and the like.

  If necessary, the soap-free emulsion coating solution may further include, for example, a matting agent, a pigment, a plasticizer, a release agent, a lubricant, a thickener, an antistatic agent, a fluorescent whitening agent, a color adjusting dye, and the like. These various additives can be arbitrarily blended.

Examples of the latex include various latexes such as SBR, MBR, and PVdc. Among these, a soap-free latex is particularly preferable. As the soap-free latex, core / shell type latex particles obtained by an emulsion polymerization method not using an emulsifier (surfactant) are suitable (for example, “Synthesis / design of acrylic resin and development of new applications” (Chubu). Management Development Center Publishing Department, issued July 1, 1985), pages 279-281).
Examples of the method for producing the soap-free latex include a seed method, a reactive emulsifier method, and an oligomer method.
The seed method is a method in which a water-dispersible polymer is prepared in advance and a monomer is added as a seed polymer for polymerization.
In the seed method, the seed polymer usually forms a core part, and the polymerized polymer forms a shell part according to the polymerization of the monomer, thereby forming a core / shell structure.

The reactive emulsifier method is a method of using a compound (reactive emulsifier) having an ethylenically unsaturated bond and an anionic or nonionic hydrophilic group in the molecule in the same manner as a conventional emulsifier. However, the reactive emulsifier used is taken into the polymer to be produced and does not remain as an emulsifier.
As the reactive emulsifier, various reactive emulsifiers are known, such as acrylic acid derivatives (JP 55-11252, JP 56-28208, etc.), itaconic acid derivatives (JP 51-51). No. -30284), maleic acid derivatives (Japanese Patent Laid-Open No. 51-30284, Japanese Patent Publication No. 56-29657, etc.), fumaric acid derivatives (Japanese Patent Laid-Open No. 51-30285, Japanese Patent Laid-Open No. 51-30284). Publication etc.).
Specifically, as a seed polymer suitable for producing the core / shell type latex resin composition, a seed polymer prepared by any of an emulsion polymerization method, a suspension polymerization method and a dispersion polymerization method is used. can do. Among these, it is appropriate to use a seed polymer prepared by an emulsion polymerization method. Even if an emulsifier is used in the emulsion polymerization method, the amount of the emulsifier can be greatly reduced by the separation and purification process. In addition, even if the seed polymer contains an emulsifier, the seed polymer is taken into the core / shell structure and does not exist on the surface of the core / shell structure. For the seed polymer prepared by the suspension polymerization method or the dispersion polymerization method, a complicated process for removing the dispersant, the solvent and the like is required.
Specifically, the seed polymer is preferably a water-soluble polymer, such as polyacrylate or a copolymer thereof, gelatin, tragacanth gum, starch, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinyl alcohol, polyvinyl Pyrrolidone and the like can be used.

  In the seed method, as the monomer to be added in the presence of the seed polymer, various ethylenically unsaturated monomers can be used as long as they can be radically polymerized. In this case, the monomer may be the same as or different from the monomer used to produce the seed polymer.

  Examples of the monomer include (meth) acrylic acid ester monomers, monovinyl aromatic monomers, (meth) vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers, halogenated olefin monomers, polyvinyl Preferable examples include system monomers.

Examples of the (meth) acrylic monomer include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( Cyclohexyl methacrylate, phenyl (meth) acrylate, methyl (meth) acrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, or And a mixture thereof.
Examples of the vinyl aromatic monomer include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p- Butylstyrene, pt-butylstyrene, p-hexylstyrene, p-octylstyrene, p-nonylstyrene, p-decylstyrene, p-dodecylstyrene, 2,4-dimethylstyrene, 3,4-dichlorostyrene, etc. Or a derivative thereof, or a mixture thereof.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl benzoate.
Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether, and the like.
Examples of the olefin monomer include monoolefin monomers such as ethylene, propylene, isobutylene, 1-butene, 1-pentene, and 4-methyl-1-pentene, and diolefin monomers such as butadiene, isoprene, and chloroprene. Can be mentioned.
Furthermore, a crosslinkable monomer may be added to improve the properties of the seed polymer. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

  In the seed method, a radical polymerization initiator can be used. The radical polymerization initiator can be appropriately used as long as it is water-soluble. Examples of such a polymerization initiator include persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4′-azobis-4-cyanovaleric acid or salts thereof, 2,2′-azobis ( 2-amidinopropane) salts), peroxide compounds, and the like.

Furthermore, the said polymerization initiator is good also as a redox-type initiator combining with a reducing agent as needed. By using the redox initiator, the polymerization activity increases, the polymerization temperature can be lowered, and the polymerization time can be expected to be shortened.
The polymerization temperature may be any temperature as long as it is equal to or higher than the lowest radical generation temperature of the polymerization initiator. For example, a range of 50 to 80 ° C. is usually used. However, it is also possible to polymerize at room temperature or lower by using a polymerization initiator that starts at room temperature, for example, a combination of hydrogen peroxide and a reducing agent (ascorbic acid or the like).

In the core / shell type latex particles, the number average molecular weight [(Mn (c)) of the core is preferably 30,000 to 500,000, and more preferably 40000 to 400,000.
On the other hand, the number average molecular weight [Mn (s)] of the shell is preferably 4000 to 30000, and more preferably 5000 to 20000.

In the core / shell type latex particles, the mass ratio of the core to the shell is preferably 10:90 to 90:10, and more preferably 20:80 to 80:20. If the mass ratio of the core to the shell is out of this range, it is difficult to fully exhibit the characteristics of the core / shell structure, and the characteristics are close to those of a simple continuous film.
The average particle size of the core / shell type latex particles is preferably 0.2 μm or less, and more preferably 0.1 μm or less. In addition, the minimum of an average particle diameter is about 0.04 micrometer, for example. When the average particle size exceeds 0.2 μm, the characteristics of the core / shell structure cannot be utilized.

  If necessary, the soap-free latex coating solution may further include, for example, matting agents, pigments, plasticizers, release agents, lubricants, thickeners, antistatic agents, fluorescent whitening agents, and color-adjusting dyes. These various additives can be arbitrarily blended.

  The glass transition temperature (Tg) of the resin in either the soap-free latex or the soap-free emulsion is preferably 30 ° C. or higher, more preferably 50 ° C. or higher.

The polymer-containing aqueous coating solution preferably contains a pigment. As the pigment, for example, titanium dioxide, calcium carbonate, clay, kaolin, talc, barium sulfate, silica and the like are preferable.
Examples of the coating method of the polymer-containing aqueous coating solution include a blade coater, an air knife coater, a roll coater, a comma coater, a brush coater, a squeeze coater, a curtain coater, a kiss coater, a bar coater, and a gravure coater. A coat is preferred.
Moreover, 0.5-30 g / m < ² > is preferable at solid content, and, as for the application | coating or impregnation amount with respect to the said base paper of the said polymer containing aqueous coating liquid, 1-15 g / m < ² > is more preferable.

-Pressure drying (press dry) treatment-
The pressure drying (press-drying) treatment is not particularly limited as long as it can soften paper fibers, approach the paper fibers, and heat-dry while pressing the pulp stock. It is possible to select appropriately according to. As the press-drying treatment, for example, the pulp paper stock is dehydrated by a hand-made machine, and the moisture content before the press-drying treatment is adjusted to 5 to 30% using a wet press device or the like, and the moisture content is adjusted. It is preferable to treat the drying temperature of the surface of the base paper on the side where the image recording layer is provided at 100 to 200 ° C.

The water content of the polymer-containing layer before the press-drying treatment is preferably 5 to 30% and more preferably 7 to 15% in order to prevent the polymer-containing layer from being crushed.
The water content of the polymer-containing layer after the press-drying treatment is not particularly limited and can be appropriately selected according to the purpose, but is preferably 10% or less, more preferably 3 to 8%.

The drying temperature of the surface of the base paper on the side where the image recording layer is provided is preferably 100 to 200 ° C, more preferably 110 to 180 ° C. When the drying temperature is less than 100 ° C., moisture does not evaporate sufficiently, the interfiber bonding becomes insufficient, and paper strength may not be obtained. In some cases, size and flatness may not be sufficient.
The press pressure in the press-drying process is preferably 0.05 to 0.5 MPa. When the press pressure is less than 0.05 MPa, the flow of fibers is small, and thus the flatness may be insufficient. When it exceeds 0.5 MPa, adhesion with the coating layer may be a problem.
The density of the press-dried base paper is preferably 0.8 g / cm ³ or more, and more preferably 0.9 g / cm ³ or more. When the density of the base paper is less than 0.8 g / cm ³ , the planarity may be insufficient.

The apparatus for performing the press-drying treatment is not particularly limited and can be appropriately selected according to the purpose. For example, as a research purpose not on a production line, the Condebelt drying method shown in FIG. The press-drying apparatus 100 is suitable.
The press drying apparatus 100 includes an upper plate 42, a lower plate 43, and a jacket 44 between the upper and lower plates, and includes other members as necessary.

In the drying using the press-drying apparatus 100, the pulp paper stock is hand-machined, and the wet paper (not shown) dehydrated using a wet press apparatus or the like is placed in a jacket 44 that does not allow air to pass through. This is performed by heating and drying and pressurizing with the upper plate 42 and the lower plate 43 whose temperature is controlled by the oil 47 heated by flowing. During pressure drying, water vapor generated from the wet paper is removed by the vacuum tank 49. Pressurization is performed by applying pressure to the lower plate 43 with the pressurizer 48 using the hydraulic oil 45. Further, the cooling water 46 is configured to flow into the apparatus during pressure drying.
As the press-drying device, for example, “Static Concert” manufactured by VALMET can be used.

In addition, when the press dry process is incorporated into the production line and the process is continuously performed, the press dry apparatus 200 shown in FIG. 2 is preferably used.
The press-drying apparatus 200 shown in FIG. 2 is arranged such that the first endless belt 38 and the second endless belt 39 that do not allow air to pass therethrough and guide heat well, and the first endless belt 38 rotates around the first endless belt 38. First rotating rollers 51 and 52, and second rotating rollers 53 and 54 arranged so that the second endless belt 39 rotates around the first rotating rollers 51 and 52.
The first endless belt 38 and the second endless belt 39 are disposed so that the endless belts travel in a part of a path parallel to each other so as to form a dry region therebetween.
The first endless belt 38 is heated in the heat chamber 55, and the second endless belt 39 is cooled in the cooling chamber 56.
Then, the dehydrated wet paper 40 and at least one fabric 11 forming an endless loop are brought into contact with the heated first endless belt 38, and the dehydrated wet paper 40 is dehydrated. It is introduced between the belts 38 and 39 so as to be between the paper 40 and the second endless belt 39 to be cooled and the guide roller for guiding the endless fabric, and is configured to be pressure-dried. Yes.
The details of the press-drying apparatus 200 are described in, for example, JP-T 2000-500536.
According to the press-drying apparatus, it is possible to achieve a good press-drying effect that is more efficient than conventional ones.

  The paper is subjected to press-drying treatment as described above to improve density, elastic modulus, tensile strength, strength, and the like, and has excellent dimensional stability and smoothness, and less curling. A high-quality image can be formed by using the support.

  The support for image recording material of the present invention comprises the paper of the present invention. The paper has a base paper and a polymer-containing layer on at least a surface of the base paper on which an image recording layer is provided, and the paper is subjected to pressure drying treatment. Thereby, in particular, it has excellent surface smoothness and extremely excellent gloss.

The center surface average roughness (SRa) at a wavelength of 5 to 6 mm on the surface on the side where the image recording layer is provided in the support for image recording material is preferably 0.5 μm or less, and more preferably 0.1 to 0.4 μm. If the center surface average roughness (SRa) exceeds 0.5 μm, the flatness after coating may be insufficient.
Here, the center surface average roughness (SRa) is an average roughness obtained by three-dimensionally scanning the roughness of a certain plane, and is obtained by scanning the linear roughness of the plane. This is a concept different from the line average roughness (Ra). The center surface average roughness (SRa) is measured under the conditions of a cutoff wavelength of 5 to 6 mm based on the following measurement and analysis conditions using, for example, a surface shape measuring device Surfcom 570A-3DF (manufactured by Tokyo Seimitsu Co., Ltd.). The center plane average roughness (SRa) can be measured.
-Measurement and analysis conditions-
-Scanning direction: MD direction of the sample-Measurement length: Papermaking (X) direction 50 mm, its vertical (Y) direction 30 mm
・ Measurement pitch: 0.1 mm in the X direction, 0.1 mm in the Y direction
・ Scanning speed: 30mm / sec
・ Band pass filter: 5-6mm

Specifically, the surface smoothness and glossiness of the image recording material support are preferably 20% or more and more preferably 40% or more at 20 ° glossiness. When the glossiness is less than 20%, glossiness after image formation may be insufficient.
Here, the 20-degree glossiness can be measured based on JIS Z8741.

As water resistance of the image-recording material support, specifically, preferably from 10 g / ^{m 2} or less Kobusaizu water absorption (30 seconds), more preferably 5 g / ^{m 2} or less, still is 4g / ^{m 2} or less preferable.
The bump size water absorption is a value obtained by measuring the water absorption when pure water is brought into contact with a sample for 120 seconds according to JIS P8140.

(Paper manufacturing method)
The paper manufacturing method of the present invention includes a polymer-containing layer forming step and a pressure drying treatment step, and further includes other steps as necessary.

The polymer-containing layer forming step is a step of forming a polymer-containing layer by applying and / or impregnating a polymer-containing coating solution on at least the surface of the base paper on which the image recording layer is provided.
In this case, it is preferable to perform the polymer-containing layer forming step on the base paper obtained by subjecting the wet paper to pressure drying treatment.
The coating method is not particularly limited and may be appropriately selected depending on the purpose. For example, blade coating method, air knife coating method, gravure coating method, roll coating coating method, spray coating method, dip coating method, bar Examples thereof include a coating method, an extrusion coating method, and a spin coating method.

The pressure drying step is a step of subjecting a base paper having a polymer-containing layer to a pressure drying treatment.
In this case, it is preferable to dry the polymer-containing layer until the water content in the polymer-containing layer is 5 to 30%, and then perform pressure drying treatment.

In addition, it is preferable that the base paper obtained by subjecting the wet paper to pressure drying treatment to be calendered can obtain excellent flatness and gloss.
The calendering treatment is not particularly limited and can be appropriately selected according to the purpose. However, high-temperature soft calendering treatment is preferable, and the surface temperature of the metal roll is preferably 110 ° C. or higher, and 150 ° C. or higher. More preferred is 250 ° C. or higher. The upper limit temperature is suitably about 300 ° C., for example.
In addition, it is preferable to perform a pressure drying process (press dry process) before the polymer adhesion process in terms of improving the flatness and rigidity.

  The paper of the present invention obtained as described above has high surface smoothness and extremely excellent gloss, and can be used for various applications, but is particularly preferably used as a support for image recording materials.

(Image recording material)
The image recording material of the present invention has at least a support and an image recording layer provided on the support, and the support is the support for an image recording material of the present invention.
The image recording material varies depending on the use and type of the image recording material, and examples thereof include an electrophotographic material, a heat sensitive material, an ink jet recording material, a sublimation transfer material, a silver salt photographic material, and a thermal transfer material.

<Electrophotographic materials>
The electrophotographic material has the support for image recording material of the present invention and at least one toner image-receiving layer provided on at least one surface of the support, and other layers appropriately selected as necessary, For example, a surface protective layer, an intermediate layer, a back layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, a tint preparation layer, a storage stability improving layer, an adhesion preventing layer, an anti-curl layer, a smoothing layer, etc. It has. Each of these layers may have a single layer structure or a laminated structure.

[Toner image receiving layer]
The toner image receiving layer is a toner image receiving layer for receiving color toner or black toner and forming an image. The toner image receiving layer has a function of receiving toner for forming an image from a developing drum or an intermediate transfer body by (static) electricity, pressure, etc. in a transfer process, and fixing it by heat, pressure, etc. in a fixing process. Have

The toner image-receiving layer is preferably a low-transparency toner image-receiving layer having a light transmittance of 78% or less from the viewpoint that the electrophotographic material of the present invention has a photographic feel, and the light transmittance is 73% or less. More preferred is 72% or less.
The light transmittance can be measured by separately forming a coating film having the same thickness on a polyethylene terephthalate film (100 μm) and using the direct reading haze meter (Suga Test Instruments HGM-2DP). .

  The toner image-receiving layer contains at least a thermoplastic resin, and various additives added for the purpose of improving the thermodynamic properties of the toner image-receiving layer, for example, a release agent, a plasticizer, a colorant, Contains a filler, a crosslinking agent, a charge control agent, an emulsifier, a dispersant and the like.

-Thermoplastic resin-
There is no restriction | limiting in particular as said thermoplastic resin, According to the objective, it can select suitably, (1) Polyolefin-type resin, (2) Polystyrene-type resin, (3) Acrylic-type resin, (4) Polyvinyl acetate Alternatively, derivatives thereof, (5) polyamide-based resin, (6) polyester resin, (7) polycarbonate resin, (8) polyether resin (or acetal resin), (9) other resins, and the like can be given. These may be used individually by 1 type and may use 2 or more types together. Of these, styrene resins, acrylic resins, and polyester resins having a large cohesive energy are particularly preferably used from the viewpoint of embedding toner.

Examples of the polyolefin-based resin (1) include polyolefin resins such as polyethylene and polypropylene, and copolymer resins of olefins such as ethylene and propylene and other vinyl monomers. Examples of the copolymer resin of the olefin and another vinyl monomer include an ethylene-vinyl acetate copolymer and an ionomer resin that is a copolymer of acrylic acid or methacrylic acid. Examples of the polyolefin resin derivative include chlorinated polyethylene and chlorosulfonated polyethylene.
Examples of the polystyrene-based resin (2) include polystyrene resin, styrene-isobutylene copolymer, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), and polystyrene-anhydrous. A maleic acid resin etc. are mentioned.
Examples of the acrylic resin (3) include polyacrylic acid or esters thereof, polymethacrylic acid or esters thereof, polyacrylonitrile, and polyacrylamide.
Examples of the esters of polyacrylic acid include homopolymers and multi-component copolymers of esters of acrylic acid. Examples of the ester of acrylic acid include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, 2-chloroethyl acrylate, And phenyl acrylate, methyl α-chloroacrylate, and the like.
Examples of the esters of polymethacrylic acid include homopolymers and multi-component copolymers of esters of methacrylic acid. Examples of the ester of methacrylic acid include methyl methacrylate, ethyl methacrylate, butyl methacrylate and the like.
Examples of the polyvinyl acetate of (4) or a derivative thereof include, for example, polyvinyl acetate, polyvinyl alcohol obtained by saponifying polyvinyl acetate, and polyvinyl alcohol as an aldehyde (for example, formaldehyde, acetaldehyde, butyraldehyde, etc.). Examples thereof include polyvinyl acetal resins obtained by reaction.
The polyamide-based resin (5) is a polycondensate of diamine and dibasic acid, and examples thereof include 6-nylon and 6,6-nylon.
The polyester resin (6) is produced by condensation polymerization of an acid component and an alcohol component. The acid component is not particularly limited and may be appropriately selected depending on the intended purpose. For example, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, terephthalic acid, isophthalic acid, succinic acid , Adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid , Isooctyl succinic acid, trimellitic acid, pyromellitic acid, acid anhydrides thereof, or lower alkyl esters thereof.
There is no restriction | limiting in particular as said alcohol component, According to the objective, it can select suitably, For example, bivalent alcohol is preferable. Examples of the aliphatic diol include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, , 5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like. Examples of the alkylene oxide adduct of bisphenol A include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxypropylene (3.3) -2,2-bis. (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2, Examples include 2-bis (4-hydroxyphenyl) propane and polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane.
The polycarbonate resin (7) is generally a polycarbonate obtained from bisphenol A and phosgene.
Examples of the polyether resin (or acetal resin) of (8) include polyether resins such as polyethylene oxide and polypropylene oxide, and acetal resins such as polyoxymethylene as a ring-opening polymerization system.
Examples of the other resin (9) include polyaddition polyurethane resins.

  The thermoplastic resin is preferably one that can satisfy the following properties of the toner image-receiving layer with the toner image-receiving layer formed, and more preferably one that can satisfy the properties of the toner-image-receiving layer described later even with the resin alone. It is also preferable to use two or more resins having different physical properties of the toner image-receiving layer in combination.

  As the thermoplastic resin, those having a larger molecular weight than the thermoplastic resin used in the toner are preferable. However, the molecular weight described above is not always preferable depending on the relationship between the thermodynamic characteristics of the thermoplastic resin used in the toner and the thermoplastic resin in the toner image receiving layer. For example, when the softening temperature of the thermoplastic resin in the toner image receiving layer is higher than the thermoplastic resin used in the toner, the molecular weight is the same or the thermoplastic resin in the toner image receiving layer is smaller. It may be preferable.

It is also preferable to use a mixture of resins having the same composition and different average molecular weights as the thermoplastic resin of the toner image-receiving layer. Further, as the relationship with the molecular weight of the thermoplastic resin used in the toner, the relationship disclosed in JP-A-8-334915 is preferable.
The molecular weight distribution of the thermoplastic resin in the toner image-receiving layer is preferably wider than the molecular weight distribution of the thermoplastic resin used in the toner.
As the thermoplastic resin of the toner image receiving layer, JP-A-5-127413, JP-A-8-194394, JP-A-8-334915, JP-A-8-334916, JP-A-9-171265 are disclosed. Those satisfying the physical properties disclosed in JP-A-10-221877 are preferred.

  The thermoplastic resin for the toner image-receiving layer is excellent in environmental suitability and work suitability because (i) the organic solvent is not discharged in the coating and drying step. (Ii) Many release agents such as wax are difficult to dissolve in a solvent at room temperature, and are often dispersed in a solvent (water, organic solvent) in advance. In addition, the water dispersion form is more stable and more suitable for the manufacturing process. Further, in the case of aqueous coating, the wax tends to bleed on the surface during the coating and drying process, and the effects of the release agent (offset resistance, adhesion resistance, etc.) can be easily obtained. For this reason, water-based resins such as water-dispersible polymers and water-soluble polymers are preferably used.

  The water-based resin is not particularly limited in terms of its composition, bond structure, molecular structure, molecular weight, molecular weight distribution, form, etc., as long as it is either a water-dispersible polymer or a water-soluble polymer. Examples of the water-based group of the polymer include a sulfonic acid group, a hydroxyl group, a carboxylic acid group, an amino group, an amide group, and an ether group.

The water-dispersible polymer is appropriately selected from, for example, resins, emulsions, copolymers, mixtures, and cation-modified products obtained by dispersing the thermoplastic resins (1) to (9) in water. More than one species can be combined.
As the water-dispersible polymer, an appropriately synthesized product or a commercially available product may be used. Examples of the commercially available products include polyester-based water-dispersible polymers such as Toyobo Co., Ltd.'s Bironal series, Takamatsu Yushi Co., Ltd. Pes Resin A series, Kao Corporation's Tufton UE series, Nippon Synthetic Chemical Examples include the Polyester WR series manufactured by Kogyo Co., Ltd., and the erière series manufactured by Unitika Ltd. Examples of the acrylic water-dispersible polymer include Hiros XE, KE, PE series manufactured by Seiko Chemical Industry Co., Ltd. and Jurimer ET series manufactured by Nippon Pure Chemical Co., Ltd.

The water dispersible emulsion is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a water dispersible polyurethane emulsion, a water dispersible polyester emulsion, a chloroprene emulsion, a styrene-butadiene emulsion, a nitrile- Butadiene emulsion, butadiene emulsion, vinyl chloride emulsion, vinylpyridine-styrene-butadiene emulsion, polybutene emulsion, polyethylene emulsion, vinyl acetate emulsion, ethylene-vinyl acetate emulsion, vinylidene chloride emulsion, methyl methacrylate Examples include butadiene emulsions. Among these, a water dispersible polyester emulsion is particularly preferable.
The water-dispersible polyester emulsion is preferably a self-dispersing water-based polyester emulsion, and among them, a carboxyl group-containing self-dispersing water-based polyester resin emulsion is particularly preferable. Here, the self self-dispersing aqueous polyester emulsion means an aqueous emulsion containing a polyester resin that can be self-dispersed in an aqueous solvent without using an emulsifier or the like. The carboxyl group-containing self-dispersing aqueous polyester resin emulsion means an aqueous emulsion containing a polyester resin that contains a carboxyl group as a hydrophilic group and can be self-dispersed in an aqueous solvent.

The self-dispersing water-dispersible polyester emulsion preferably satisfies the following characteristics (1) to (4). Since this is a self-dispersion type that does not use a surfactant, it has low hygroscopicity even in a high humidity atmosphere, and there is little decrease in the softening point due to moisture, and it is possible to suppress the occurrence of offset during fixing and the failure of adhesion between sheets during storage. In addition, it is environmentally friendly and workable because it is water-based. In addition, since a polyester resin with a high cohesive energy and a molecular structure is used, it has a sufficient hardness in the storage environment, but it becomes a low elasticity (low viscosity) molten state in the electrophotographic fixing process, and the toner receives an image. Sufficient image quality can be achieved by embedding in the layer.
(1) The number average molecular weight (Mn) is preferably 5,000 to 10,000, and more preferably 5,000 to 7,000.
(2) The molecular weight distribution (weight average molecular weight / number average molecular weight) is preferably 4 or less, and more preferably Mw / Mn ≦ 3.
(3) The glass transition temperature (Tg) is preferably 40 to 100 ° C, and more preferably 50 to 80 ° C.
(4) The volume average particle diameter is preferably 20 to 200 nm, more preferably 40 to 150 mm.
The content of the water-dispersible emulsion in the toner image-receiving layer is preferably 10 to 90% by mass, and more preferably 10 to 70% by mass.

There is no restriction | limiting in particular as said water-soluble polymer, According to the objective, it can select suitably, What was synthesize | combined suitably may be used and a commercial item may be used, for example, polyvinyl alcohol, carboxy Modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate, polyethylene oxide, gelatin, cationized starch, casein, sodium polyacrylate, sodium styrene-maleic anhydride copolymer, sodium polystyrene sulfonate, etc. Among these, polyethylene oxide is preferable.
Commercially available water-soluble polymers include water-soluble polyester plus coats manufactured by Kureai Chemical Industry Co., Ltd., Finetex ES series manufactured by Dainippon Ink and Chemicals, and Nippon Pure Chemical Co., Ltd. as water-soluble acrylics. Jurimer AT series, Dainippon Ink & Chemicals Finetex 6161, K-96; Seiko Chemical Industries high loss NL-1189, BH-997L, and the like.
Examples of the water-soluble polymer include Research Disclosure No. 17,643, page 26, Research Disclosure No. 18,716, page 651, Research Disclosure No. 307,105, pages 873-874, and JP-A 64- The thing described in 13546 gazette is mentioned.

The content of the water-soluble polymer in the toner image-receiving layer is not particularly limited and can be appropriately selected according to the purpose, and is preferably 0.5 to ² g / m ² .

Although the said thermoplastic resin can also be used together with another polymer material, in that case, generally it is used so that content may become larger than another polymer material.
The content of the thermoplastic resin for the toner image-receiving layer in the toner image-receiving layer is preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 50% by mass or more, and particularly preferably 50 to 90% by mass. .

-Release agent-
The release agent is blended in the toner image receiving layer in order to prevent the toner image receiving layer from being offset. The release agent used in the present invention is heated and melted at the fixing temperature, deposited on the surface of the toner image-receiving layer, unevenly distributed on the surface of the toner image-receiving layer, and further cooled and solidified to form the surface of the toner image-receiving layer. The type of the release agent material is not particularly limited as long as it forms a layer of the release agent material, and can be appropriately selected according to the purpose.
Examples of the release agent include at least one selected from a silicone compound, a fluorine compound, a wax, and a matting agent.

  As the mold release agent, for example, compounds described in Sachishobo "Revised Wax Properties and Applications", a silicone handbook published by Nikkan Kogyo Shimbun, Ltd. can be used. Also, Japanese Patent Publication No. 59-38581, Japanese Patent Publication No. 4-32380, Japanese Patent No. 2838498, Japanese Patent No. 2949558, Japanese Patent Application Laid-Open No. 50-117433, Japanese Patent Application Laid-Open No. 52-52640, Japanese Patent Application Laid-Open No. 57-148755, JP 61-62056, JP 61-62057, JP 61-118760, JP 2-42451, JP 3-41465, JP 4-212175, JP 4-214570. JP-A-4-263267, JP-A-5-34966, JP-A-5-119514, JP-A-6-59502, JP-A-6-161150, JP-A-6-175396, JP-A-6-219040. JP-A-6-230600, JP-A-6-295093, JP-A-7-36210, JP-A-7-43940, JP-A-7-56387. JP-A-7-56390, JP-A-7-64335, JP-A-7-199681, JP-A-7-223362, JP-A-7-287413, JP-A-8-184992, JP-A-8-227180, Special Kaihei 8-248671, JP-A-8-248799, JP-A-8-248801, JP-A-8-278663, JP-A-9-152727, JP-A-9-160278, JP-A-9-185181, JP-A-9-185181 Nos. 9-319139, 9-319143, 10-20549, 10-48889, 10-198069, 10-207116, 11-2917, 11 -44969, JP-A-11-65156, JP-A-11-73049, JP-A-11-194542 Silicone compound used in the toner, fluorine compounds or waxes can also be preferably used. Further, a plurality of these compounds can be used in combination.

  Examples of the silicone compound include silicone oil, silicone rubber, silicone fine particles, silicone-modified resin, and reactive silicone compound.

Examples of the silicone oil include non-modified silicone oil, amino-modified silicone oil, carboxy-modified silicone oil, carbinol-modified silicone oil, vinyl-modified silicone oil, epoxy-modified silicone oil, polyether-modified silicone oil, silanol-modified silicone oil, Examples include methacryl-modified silicone oil, mercapto-modified silicone oil, alcohol-modified silicone oil, alkyl-modified silicone oil, and fluorine-modified silicone oil.
Examples of the silicone-modified resin include olefin resin, polyester resin, vinyl resin, polyamide resin, cellulose resin, phenoxy resin, vinyl chloride-vinyl acetate resin, urethane resin, acrylic resin, styrene-acrylic resin, or a copolymer thereof. Examples thereof include resins obtained by modifying the resin with silicone.

  The fluorine compound is not particularly limited and may be appropriately selected depending on the purpose. For example, fluorine oil, fluorine rubber, fluorine-modified resin, fluorine sulfonic acid compound, fluorosulfonic acid, fluoric acid compound or a salt thereof, An inorganic fluoride etc. are mentioned.

The wax can be roughly classified into natural wax and synthetic wax.
The natural wax is preferably at least one selected from plant waxes, animal waxes, mineral waxes and petroleum waxes, and among these, plant waxes are particularly preferred. The natural wax is particularly preferably a water-dispersed wax from the viewpoint of compatibility when a water-based resin is used as the polymer for the toner image-receiving layer.

There is no restriction | limiting in particular as said plant-type wax, It can select suitably from well-known things, A commercial item may be sufficient and what was synthesize | combined suitably may be sufficient. Examples of the plant wax include carnauba wax, castor oil, rapeseed oil, soybean oil, wood wax, cotton wax, rice wax, sugarcane wax, candelilla wax, Japan wax, jojoba oil and the like.
Examples of the commercially available carnauba wax include EMUSTAR-0413 manufactured by Nippon Seiki Co., Ltd., Cellosol 524 manufactured by Chukyo Yushi Co., Ltd., and the like. As a commercial item of the said castor oil, the refined castor oil etc. by Ito Oil Co., Ltd. are mentioned.
Among these, in particular, the melting point is 70 in that an electrophotographic material that is excellent in offset resistance, adhesion resistance, paper passing property, glossiness, hardly cracks, and can form a high-quality image can be provided. Carnauba wax at ˜95 ° C. is particularly preferred.

  There is no restriction | limiting in particular as said animal-type wax, It can select suitably from well-known things, For example, beeswax, lanolin, spermaceti, stew wax (whale oil), wool wax etc. are mentioned.

There is no restriction | limiting in particular as said mineral-type wax, It can select suitably from well-known things, A commercial item may be sufficient and what was synthesize | combined suitably may be sufficient. Examples include montan wax, montan ester wax, ozokerite, ceresin and the like.
Among these, in particular, the melting point is 70 in that it is excellent in offset resistance, adhesion resistance, paper passing property, glossiness, is hardly cracked, and can provide an electrophotographic material capable of forming a high-quality image. A montan wax at ˜95 ° C. is particularly preferred.

  There is no restriction | limiting in particular as said petroleum wax, It can select suitably from well-known things, A commercial item may be sufficient and what was synthesize | combined suitably may be sufficient. Examples thereof include paraffin wax, microcrystalline wax, and petrolatum.

The content in the toner image-receiving layer of the natural wax is preferably ^{0.1~4g / m 2, 0.2~2g / m} 2 is more preferable.
When the content is less than 0.1 g / m ^2, offset resistance, it may adhesion resistance is particularly insufficient, when it exceeds 4g / m ^2, amount of the wax is too much, the image to be formed May be inferior in image quality.

  The melting point (° C.) of the natural wax is particularly preferably 70 to 95 ° C. and more preferably 75 to 90 ° C. from the viewpoint of offset resistance and paper passing.

  The synthetic wax is classified into synthetic hydrocarbons, modified waxes, hydrogenated waxes, and other oil-based synthetic waxes. These waxes are preferably water-dispersed waxes in view of compatibility when a water-based thermoplastic resin is used as the thermoplastic resin of the toner image-receiving layer.

Examples of the synthetic hydrocarbon include Fischer-Tropsch wax and polyethylene wax.
Examples of the oil-based synthetic wax include acid amide compounds (such as stearamide) and acid imide compounds (such as phthalic anhydride imide).

  The modified wax is not particularly limited and may be appropriately selected depending on the purpose. Examples thereof include amine-modified wax, acrylic acid-modified wax, fluorine-modified wax, olefin-modified wax, urethane-type wax, and alcohol-type wax. Can be mentioned.

  The hydrogenated wax is not particularly limited and may be appropriately selected depending on the intended purpose.For example, hydrogenated castor oil, castor oil derivative, stearic acid, lauric acid, myristic acid, palmitic acid, behenic acid, sebacic acid, Examples include undecylenic acid, heptylic acid, maleic acid, highly maleated oil, and the like.

The melting point (° C.) of the release agent is preferably 70 to 95 ° C., and more preferably 75 to 90 ° C., particularly in terms of offset resistance and paper passing properties.
In addition, as a release agent added to the toner image-receiving layer of the present invention, these derivatives, oxides, purified products, and mixtures can also be used. Moreover, these may have a reactive substituent.

The content of the release agent is preferably 0.1 to 10% by mass, more preferably 0.3 to 8.0% by mass, and 0.5 to 5.0% by mass based on the mass of the toner image-receiving layer. Is more preferable.
When the content is less than 0.1% by mass, the offset resistance and adhesion resistance may be insufficient. When the content exceeds 10% by mass, the amount of the release agent is excessively large. Image quality may be degraded.

-Plasticizer-
There is no restriction | limiting in particular as said plasticizer, The plasticizer for well-known resin can be suitably selected according to the objective. The plasticizer has a function of adjusting the flow or softening of the toner image-receiving layer by heat or pressure when fixing the toner.
The plasticizers include “Chemical Handbook” (edited by the Chemical Society of Japan, Maruzen), “Plasticizers—Theory and Applications” (Kouichi Murai, edited by Koshobo), “Research on plasticizers”, “Research on plasticizers” "Lower" (edited by Polymer Chemistry Association), "Handbook Rubber and Plastic Compounded Chemicals" (edited by Rubber Digest Co., Ltd.), etc.

Examples of the plasticizer include those described as high-boiling organic solvents and thermal solvents. For example, JP-A-59-83154, JP-A-59-178451, JP-A-59-178453, JP 59-178454, JP 59-178455, JP 59-178457, JP 62-174754, JP 62-245253, JP 61-209444, JP Described in JP-A-61-200538, JP-A-62-2145, JP-A-62-2348, JP-A-62-2247, JP-A-62-136646, JP-A-2-235694, etc. Esters such as phthalates, phosphate esters, fatty acid esters, abietic acid esters, adipic acid esters, sebacic acid esters, Gelaic acid esters, benzoic acid esters, butyric acid esters, epoxidized fatty acid esters, glycolic acid esters, propionic acid esters, trimellitic acid esters, citric acid esters, sulfonic acid esters, carboxylic acid esters Succinic acid esters, maleic acid esters, fumaric acid esters, phthalic acid esters, stearic acid esters, etc.), amides (for example, fatty acid amides, sulfoamides, etc.), ethers, alcohols, lactones And compounds such as polyethyleneoxys.
These plasticizers can be used by mixing with a resin.

Furthermore, as the plasticizer, a polymer having a relatively low molecular weight can be used. The molecular weight of the plasticizer is preferably lower than the molecular weight of the binder resin to be plasticized, and the molecular weight is preferably 15000 or less, more preferably 5000 or less. In the case of a polymer plasticizer, the polymer is preferably the same type as the binder resin to be plasticized. For example, a low molecular weight polyester is preferable for plasticizing a polyester resin. Furthermore, oligomers can also be used as plasticizers.
In addition to the compounds listed above, commercially available products include, for example, Adekasizer PN-170, PN-1430 (all manufactured by Asahi Denka Kogyo Co., Ltd.), PARAPLEX-G-25, G-30, G-40 (any C.P.HALL), ester gum 8L-JA, ester R-95, pentalin 4851, FK115, 4820, 830, Louisol 28-JA, picolastic A75, picotex LC, crystallx 3085 (all are rationalized) Hercules).

The plasticizer is used for stress and strain generated when toner particles are embedded in the toner image-receiving layer (physical strain such as elastic force and viscosity, strain due to material balance of molecules, binder main chain, pendant portion, etc.). Can be used arbitrarily to alleviate.
The plasticizer may be in a micro-dispersed state in the toner image-receiving layer, in a micro-phase-separated state in a sea island shape, or in a state sufficiently mixed and dissolved with other components such as a binder. .
The content of the plasticizer in the toner image-receiving layer is preferably 0.001 to 90% by mass, more preferably 0.1 to 60% by mass, and still more preferably 1 to 40% by mass.
The plasticizer adjusts smoothness (improves transportability due to reduced frictional force), improves fixing unit offset (detachment of toner and layers from the fixing unit), adjusts curl balance, and adjusts charging (toner electrostatic image It may be used for the purpose of forming).

-Colorant-
There is no restriction | limiting in particular as said colorant, According to the objective, it can select suitably, A fluorescent whitening agent, a white pigment, a colored pigment, dye, etc. are mentioned.
The fluorescent brightening agent is not particularly limited as long as it is a known compound that absorbs in the near ultraviolet region and emits fluorescence at 400 to 500 nm, and can be appropriately selected from known compounds. Preferable examples include compounds described in “The Chemistry of Synthetic Dies” edited by Veen Rataraman, Vol. The fluorescent brightening agent may be a commercially available product, or may be appropriately synthesized. For example, a stilbene compound, a coumarin compound, a biphenyl compound, a benzoxazoline compound, a naphthalimide compound , Pyrazoline compounds, carbostyryl compounds, and the like. Examples of the commercially available products include white fur fur PSN, PHR, HCS, PCS, B (all manufactured by Sumitomo Chemical Co., Ltd.), UVITEX-OB (manufactured by Ciba-Geigy), and the like.

  There is no restriction | limiting in particular as said white pigment, According to the objective, it can select suitably according to the objective, For example, inorganic pigments, such as a titanium oxide and a calcium carbonate, can be used.

The colored pigment is not particularly limited and may be appropriately selected from known ones according to the purpose. Examples thereof include various pigments, azo pigments, and many described in JP-A-63-44653. Examples thereof include cyclic pigments, condensed polycyclic pigments, lake pigments, and carbon black.
Examples of the azo pigment include azo lake (for example, Carmine 6B, Red 2B, etc.), insoluble azo pigment (for example, monoazo yellow, disazo yellow, pyrazolo orange, vulcan orange), and condensed azo pigments (for example, chromophthal yellow, chromo). Phthared).
Examples of the polycyclic pigment include phthalocyanine pigments such as copper phthalocyanine blue and copper phthalocyanine green.
Examples of the condensed polycyclic pigment include dioxazine pigments (such as dioxazine violet), isoindolinone pigments (such as isoindolinone yellow), selenium pigments, perylene pigments, perinone pigments, and thioindigo pigments. Can be mentioned.
Examples of the lake pigment include malachite green, rhodamine B, rhodamine G, and Victoria blue B.
Examples of the inorganic pigment include oxides (for example, titanium dioxide, bengara, etc.) sulfates (for example, precipitated barium sulfate), carbonates (for example, precipitated calcium carbonate), oxalates (for example, water-containing materials) Succinate, anhydrous succinate, etc.), metal powders (for example, aluminum powder, bronze powder, zinc dust, yellow lead, bitumen), and the like.
These may be used alone or in combination of two or more.

There is no restriction | limiting in particular as said dye, According to the objective, it can select suitably according to the objective, For example, an anthraquinone type compound, an azo type compound, etc. are mentioned. These may be used alone or in combination of two or more.
Examples of water-insoluble dyes include vat dyes, disperse dyes, and oil-soluble dyes. Examples of the vat dyes include C.I. I. Vat violet 1, C.I. I. Vat violet 2, C.I. I. Vat violet 9, C.I. I. Vat violet 13, C.I. I. Vat violet 21, C.I. I. Vat Blue 1, C.I. I. Vat Blue 3, C.I. I. Vat Blue 4, C.I. I. Vat Blue 6, C.I. I. Vat Blue 14, C.I. I. Vat Blue 20, C.I. I. Vat blue 35 etc. are mentioned. Examples of the disperse dye include C.I. I. Dispers Violet 1, C.I. I. Disperse Violet 4, C.I. I. Disperse Violet 10, C.I. I. Disperse Blue 3, C.I. I. Disperse Blue 7, C.I. I. Disperse Blue 58 etc. are mentioned. Examples of the oil-soluble dye include C.I. I. Solvent Violet 13, C.I. I. Solvent Violet 14, C.I. I. Solvent Violet 21, C.I. I. Solvent Violet 27, C.I. I. Solvent Blue 11, C.I. I. Solvent Blue 12, C.I. I. Solvent Blue 25, C.I. I. Solvent Blue 55 etc. are mentioned.
In addition, a colored coupler used in silver salt photography can also be suitably used.

Of the colorant, the content in the toner image-receiving layer is preferably ^{0.1~8g / m 2, 0.5~5g / m} 2 is more preferable.
When the content of the colorant is less than 0.1 g / m ^2, there is the light transmittance is high in the toner image-receiving layer, it exceeds 8 g / m ^2, cracks, the handling properties of adhesion resistance, etc. May be inferior.
Among the colorants, the amount of pigment added is preferably 40% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less based on the mass of the thermoplastic resin constituting the toner image-receiving layer. preferable.

As said filler, an organic or inorganic filler is mentioned, A well-known thing can be used as a reinforcing agent for binder resin, a filler, and a reinforcing material. The filler should be selected with reference to "Handbook Rubber / Plastic Compounding Chemicals" (edited by Rubber Digest Co., Ltd.), "New Edition Plastic Compounding Agent Fundamentals and Applications" (Taiseisha), "Filler Handbook" (Taiseisha), etc. Can do.
Moreover, an inorganic filler or an inorganic pigment can be used as the filler. Examples of the inorganic filler or inorganic pigment include silica, alumina, titanium dioxide, zinc oxide, zirconium oxide, mica-like iron oxide, lead white, lead oxide, cobalt oxide, strontium chromate, molybdenum-based pigment, smectite, magnesium oxide, Examples include calcium oxide, calcium carbonate, and mullite. Among these, silica and alumina are particularly preferable. These may be used alone or in combination of two or more. The filler preferably has a small particle size. If the particle size is large, the surface of the toner image-receiving layer tends to be roughened.

  The silica includes spherical silica and amorphous silica. The silica can be synthesized by a dry method, a wet method, or an airgel method. The surface of the hydrophobic silica particles may be surface-treated with a trimethylsilyl group or silicone. As the silica, colloidal silica is preferable. The silica is preferably porous.

The alumina includes anhydrous alumina and alumina hydrate. As the crystal form of the anhydrous alumina, α, β, γ, δ, ζ, η, θ, κ, ρ, or χ can be used, and alumina hydrate is preferable to anhydrous alumina. As the alumina hydrate, monohydrate or trihydrate can be used. The monohydrate includes pseudo boehmite, boehmite and diaspore. The trihydrate includes dibsite and bayerite. The alumina is preferably porous.
The alumina hydrate can be synthesized by a sol-gel method in which ammonia is added to an aluminum salt solution for precipitation or a method in which an alkali aluminate is hydrolyzed. The anhydrous alumina can be obtained by dehydrating alumina hydrate by heating.

  The amount of the filler added is preferably 5 to 2000 parts by mass with respect to 100 parts by mass of the dry mass of the binder of the toner image receiving layer.

The cross-linking agent can be blended in order to adjust the storage stability and thermoplasticity of the toner image-receiving layer. As the cross-linking agent, a compound having two or more known reactive groups in the molecule as epoxy groups, isocyanate groups, aldehyde groups, active halogen groups, active methylene groups, acetylene groups and the like as reactive groups is used.
As the cross-linking agent, a compound having two or more groups capable of forming a bond by a hydrogen bond, an ionic bond, a coordinate bond, or the like can be used.
As the crosslinking agent, for example, a known compound can be used as a coupling agent for resin, a curing agent, a polymerization agent, a polymerization accelerator, a coagulant, a film-forming agent, a film-forming auxiliary, and the like. Examples of the coupling agent include chlorosilanes, vinyl silanes, epoxy silanes, aminosilanes, alkoxyaluminum chelates, titanate coupling agents, etc., and “Handbook Rubber / Plastic Compounding Chemicals” (edited by Rubber Digest Co., Ltd.). ) Etc. can be used.

The toner image receiving layer of the present invention preferably contains a charge adjusting agent in order to adjust the transfer or adhesion of the toner or prevent the toner image receiving layer from being charged and adhered.
The charge control agent is not particularly limited, and various conventionally known charge control agents can be appropriately used according to the purpose. For example, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, In addition to surfactants such as nonionic surfactants, polymer electrolytes, conductive metal oxides, and the like can be used. Specifically, quaternary ammonium salts, polyamine derivatives, cation-modified polymethyl methacrylate, cationic antistatic agents such as cation-modified polystyrene, anionic antistatic agents such as alkyl phosphates and anionic polymers, fatty acid esters, polyethylene oxide Nonionic antistatic agents such as
When the toner has a negative charge, for example, a cation or a nonion is preferable as the charge adjusting agent blended in the toner image receiving layer.
Examples of the conductive metal oxide include ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, and MoO ₃ . These may be used alone or in combination of two or more. The conductive metal oxide may further contain (doping) a different element, for example, Al, In, etc. with respect to ZnO, Nb, Ta, etc. with respect to TiO ₂ , and SnO ₂ . Can contain (doping) Sb, Nb, a halogen element, or the like.

-Other additives-
The material that can be used in the toner image-receiving layer of the present invention can contain various additives for improving the stability of the output image and improving the stability of the toner image-receiving layer itself. Examples of the additive include various known antioxidants, antioxidants, deterioration inhibitors, ozone deterioration inhibitors, ultraviolet absorbers, metal complexes, light stabilizers, preservatives, fungicides, and the like.

  There is no restriction | limiting in particular as said antioxidant, According to the objective, it can select suitably, For example, a chroman compound, a coumaran compound, a phenol compound (for example, hindered phenol), a hydroquinone derivative, a hindered amine derivative, a spiroindane compound is mentioned. Can be mentioned. The antioxidant is described in JP-A No. 61-159644.

  There is no restriction | limiting in particular as said anti-aging agent, According to the objective, it can select suitably, For example, it describes in "Handbook rubber and plastic compounding chemicals revised 2nd edition" (1993, Rubber Digest company) p76-121. Can be mentioned.

  There is no restriction | limiting in particular as said ultraviolet absorber, According to the objective, it can select suitably, For example, a benzotriazole compound (refer U.S. Pat. No. 3,533,794), 4-thiazolidone compound (U.S. Pat. No. 3,352,681) And benzophenone compounds (see JP-A No. 46-2784), and UV-absorbing polymers (see JP-A No. 62-260152).

There is no restriction | limiting in particular as said metal complex, According to the objective, it can select suitably, For example, each specification of U.S. Pat. No. 4,241,155, U.S. Pat. No. 4,245,018, U.S. Pat. Those described in JP-A-88256, JP-A-62-174741, JP-A-63-199248, JP-A-1-75568, and JP-A-1-74272 are suitable.
Further, ultraviolet absorbers and light stabilizers described in "Handbook Rubber / Plastic Compounding Chemicals Revised Second Edition" (1993, Rubber Digest Co., Ltd.) p122 to 137 can also be suitably used.

  In addition, as described above, a known photographic additive can be added to the material that can be used for the toner image-receiving layer of the present invention, if necessary. Examples of the photographic additive include Research Disclosure Magazine (hereinafter abbreviated as RD) No. 17643 (December 1978), RD No. 18716 (November 1979) and RD No. 307105 (November 1989), and the corresponding parts are summarized in the following table.

  The toner image-receiving layer is provided by applying a coating solution containing the toner image-receiving layer thermoplastic resin on the support with a wire coater or the like and drying. The film forming temperature (MFT) of the thermoplastic resin used in the present invention is preferably room temperature or higher for storage before printing, and preferably 100 ° C. or lower for fixing toner particles.

The toner image-receiving layer, the coating weight after drying, for example, preferably ^{1~20g / m 2, 4~15g / m} 2 is more preferable.
The thickness of the toner image-receiving layer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 1/2 or more of the particle diameter of the toner used, and is 1 to 3 times thicker. More specifically, 1-50 micrometers is preferable, 1-30 micrometers is more preferable, 2-20 micrometers is still more preferable, and 5-15 micrometers is especially preferable.

[Physical properties of toner image-receiving layer]
The toner image-receiving layer has a 180 degree peel strength at a fixing temperature with the fixing member of preferably 0.1 N / 25 mm or less, and more preferably 0.041 N / 25 mm or less. The 180 degree peel strength can be measured according to the method described in JIS K6887 using the surface material of the fixing member.
The toner image receiving layer preferably has a high whiteness. The whiteness is preferably 85% or more as measured by the method defined in JIS P 8123. In addition, in the wavelength region of 440 nm to 640 nm, the spectral reflectance is preferably 85% or more, and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength region is preferably within 5%. Furthermore, the spectral reflectance is preferably 85% or more in the wavelength region of 400 nm to 700 nm, and the difference between the maximum spectral reflectance and the minimum spectral reflectance in the same wavelength region is more preferably within 5%.
As the whiteness, specifically, in the CIE 1976 (L ^* a ^* b ^* ) color space, the L ^* value is preferably 80 or more, more preferably 85 or more, and still more preferably 90 or more. The white color is preferably as neutral as possible. As a white color, in the L ^* a ^* b ^* space, the value of (a ^* ) ² + (b ^* ) ² is preferably 50 or less, more preferably 18 or less, and still more preferably 5 or less.

The toner image receiving layer preferably has high gloss after image formation. The glossiness is preferably 60 or more, more preferably 75 or more, and even more preferably 90 or more in the entire region from white without toner to black having the maximum density.
However, the glossiness is preferably 110 or less. If it exceeds 110, it becomes like metallic luster, which is not preferable as image quality.
Here, the glossiness can be measured based on, for example, JIS Z8741.

The toner image receiving layer preferably has high smoothness after fixing. As the smoothness, the arithmetic average roughness (Ra) is preferably 3 μm or less, more preferably 1 μm or less, and even more preferably 0.5 μm or less in the entire region from white without toner to black having the maximum density.
Here, the arithmetic average roughness can be measured based on, for example, JIS B0601, JIS B0651, and JIS B0652.

The toner image-receiving layer preferably has a physical property of one item in the following items, more preferably has a physical property of a plurality of items, and further preferably has a physical property of all items.
(1) Tm (melting temperature) of the toner image-receiving layer is preferably 30 ° C. or higher, and preferably Tm + 20 ° C. or lower of the toner.
(2) The temperature at which the viscosity of the toner image-receiving layer becomes 1 × 10 ⁵ cp is preferably 40 ° C. or higher, and is preferably lower than that of the toner.
(3) The storage elastic modulus (G ′) at the fixing temperature of the toner image receiving layer is 1 × 10 ² to 1 × 10 ⁵ Pa, and the loss elastic modulus (G ″) is 1 × 10 ² to 1 × 10 ⁵ Pa. preferable.
(4) The loss tangent (G ″ / G ′), which is the ratio of the loss elastic modulus (G ″) at the fixing temperature of the toner image receiving layer and the storage elastic modulus (G ′), is preferably from 0.01 to 10.
(5) The storage elastic modulus (G ′) at the fixing temperature of the toner image-receiving layer is preferably −50 to +2500 with respect to the storage elastic modulus (G ′) at the fixing temperature of the toner.
(6) The inclination angle of the molten toner on the toner image-receiving layer is preferably 50 degrees or less, and more preferably 40 degrees or less.
The toner image-receiving layer satisfies the physical properties disclosed in Japanese Patent No. 2788358, Japanese Patent Application Laid-Open No. 7-248637, Japanese Patent Application Laid-Open No. 8-305067, Japanese Patent Application Laid-Open No. 10-239889, and the like. preferable.

The surface electric resistance of the toner image-receiving layer is preferably in the range of 1 × 10 ⁶ to 1 × 10 ¹⁵ Ω / cm ² (under the condition of 25 ° C.-65% RH).
If the surface resistance is less than 1 × 10 ⁶ Ω / cm ² , the amount of toner when the toner is transferred to the toner image-receiving layer is not sufficient, and the density of the resulting toner image may tend to be low. If it exceeds × 10 ¹⁵ Ω / cm ² , an excessive charge is generated at the time of transfer, the toner is not sufficiently transferred, the density of the image is low, and electrostatic charges and dust adhere to the electrophotographic material during handling. It becomes easy. Misfeeds, double feeds, discharge marks, toner transfer missing, etc. may occur during copying.
Here, the surface electrical resistance is based on JIS K6911, the sample is conditioned for 8 hours or more in an environment of a temperature of 20 ° C. and a humidity of 65%, and under the same environment, R8340 manufactured by Advantest Corporation is used. It can be obtained by measuring after one minute has passed after energization under the condition of an applied voltage of 100V.

[Other layers]
Examples of the other layers in the electrophotographic material include a surface protective layer, a back layer, an adhesion improving layer, an intermediate layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, a tint adjusting layer, and storage stability. Examples include an improved layer, an adhesion preventing layer, an anti-curl layer, and a smoothing layer. These layers may be composed of a single layer or may be composed of two or more layers.

-Surface protective layer-
The surface protective layer is the toner image-receiving layer for the purpose of protecting the surface of the electrophotographic material, improving storage stability, improving handleability, imparting writability, improving instrument passability, imparting anti-offset property, etc. Can be provided on the surface. The surface protective layer may be a single layer or may be composed of two or more layers. In the surface protective layer, various thermoplastic resins, thermosetting resins, and the like can be used as a binder, and it is preferable to use the same type of resin as the toner image receiving layer. However, thermodynamic characteristics, electrostatic characteristics, and the like do not need to be the same as those of the toner image-receiving layer, and can be optimized.

The surface protective layer may contain the various additives described above that can be used for the toner image-receiving layer. In particular, the surface protective layer may be blended with other additives such as a matting agent in addition to the release agent used in the present invention. In addition, as said mat agent, various well-known things are mentioned.
The outermost surface layer in the electrophotographic material (for example, a surface protective layer when a surface protective layer is formed) preferably has good compatibility with the toner from the viewpoint of fixability. Specifically, the contact angle with the melted toner is preferably, for example, 0 to 40 degrees.

-Back layer-
In the electrophotographic material, the back layer is provided on the opposite side of the toner image-receiving layer with respect to the support for the purpose of imparting backside output suitability, improving backside output image quality, improving curl balance, improving device passability, and the like. Is preferred.
Although there is no restriction | limiting in particular as a color of the said back layer, When the said electrophotographic material is a double-sided output type image receiving sheet which forms an image also in a back surface, it is preferable that a back layer is also white. The whiteness and the spectral reflectance are preferably 85% or more like the surface.
Further, the back layer may have the same structure as that of the toner image receiving layer for improving the duplex output suitability. Various additives described above can be used for the back layer. As such an additive, it is particularly suitable to blend a matting agent, a charge adjusting agent and the like. The back layer may have a single layer configuration or a stacked configuration of two or more layers.
Further, in order to prevent offset at the time of fixing, when a releasable oil is used for the fixing roller or the like, the back layer may be oil absorbing.
The thickness of the back layer is usually preferably from 0.1 to 10 μm.

-Adhesion improvement layer, etc.-
The adhesion improving layer is preferably formed for the purpose of improving the adhesion between the support and the toner image receiving layer in the electrophotographic material. The above-mentioned various additives can be blended in the adhesion improving layer, and it is particularly preferable to blend a crosslinking agent. The electrophotographic material of the present invention preferably further comprises a cushion layer or the like between the adhesion improving layer and the toner image receiving layer in order to improve the toner acceptability.

-Intermediate layer-
The intermediate layer is formed, for example, between the support and the adhesion improving layer, between the adhesion improving layer and the cushion layer, between the cushion layer and the toner image receiving layer, and between the toner image receiving layer and the storage stability improving layer. Can do. Of course, in the case of an electrophotographic material comprising a support, a toner image receiving layer and an intermediate layer, the intermediate layer can be present, for example, between the support and the toner image receiving layer.

  In addition, there is no restriction | limiting in particular as thickness of the said electrophotographic material of this invention, Although it can select suitably according to the objective, For example, 50-550 micrometers is preferable and 100-350 micrometers is more preferable.

<Toner>
The electrophotographic material of the present invention is used by allowing the toner image-receiving layer to receive toner during printing or copying.
The toner contains at least a binder resin and a colorant, and further contains a release agent and other components as necessary.

-Toner binder resin-
The binder resin is not particularly limited and can be appropriately selected from those usually used for toner according to the purpose. For example, styrenes such as styrene and parachlorostyrene; vinyl naphthalene, vinyl chloride Vinyl esters such as vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, Methylene aliphatic carboxylic acid esters such as n-octyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate; acrylonitrile, methacrylonitrile, Vinyl nitrile such as acrylamide Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone; methacrylic acid, acrylic Homopolymers of vinyl monomers such as vinyl carboxylic acids such as acid and cinnamic acid or copolymers thereof, and various polyesters can be used, and various waxes can be used in combination.
Among these resins, it is preferable to use a resin of the same system as that used in the toner image receiving layer of the present invention.

-Toner colorant-
The colorant is not particularly limited and may be appropriately selected according to the purpose from those usually used in toners. Yellow, Permanent Orange GTR, Pyrazolone Orange, Vulcan Orange, Watch Young Red, Permanent Red, Brilliantamine 3B, Brilliantamine 6B, Dapon Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Rose Bengal Various pigments such as aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, and malachite green oxalelate It is. Acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenyl Examples include various dyes such as methane, diphenylmethane, thiazine, thiazole, and xanthene.
These colorants may be used alone or in combination of two or more.
There is no restriction | limiting in particular in content of the said coloring agent, According to the objective, it can select suitably, The range of 2-8 mass% is preferable. When the content of the colorant is less than 2% by mass, the coloring power may be weakened, and when it exceeds 8% by mass, the transparency may be impaired.

-Toner release agent-
The release agent is not particularly limited and can be appropriately selected from those usually used for toner according to the purpose. For example, a relatively low molecular weight highly crystalline polyethylene wax, Fischer-Tropsch wax is used. In particular, polar waxes containing nitrogen such as amide waxes and compounds having urethane bonds are particularly effective.
The molecular weight of the polyethylene wax is preferably 1000 or less, and more preferably 300 to 1000.
The compound having a urethane bond is suitable because even if it has a low molecular weight, the solid state can be maintained and the melting point can be set high for the molecular weight due to the strength of cohesive force due to the polar group. A preferable range of the molecular weight is 300 to 1,000. Raw materials are combinations of diisocyanate compounds and monoalcohols, combinations of monoisocyanic acid and monoalcohols, combinations of dialcohols and monoisocyanic acid, combinations of trialcohols and monoisocyanic acid, triisocyanic acid Various combinations such as combinations of compounds and monoalcohols can be selected, but in order not to increase the molecular weight, it is preferable to combine a compound of a polyfunctional group and a monofunctional group, and an equivalent functional group It is important to be in quantity.

Examples of the monoisocyanate compound include dodecyl isocyanate, phenyl isocyanate and derivatives thereof, naphthyl isocyanate, hexyl isocyanate, benzyl isocyanate, butyl isocyanate, and allyl isocyanate.
Examples of the diisocyanate compound include tolylene diisocyanate, 4,4'diphenylmethane, toluene diisocyanate, 1,3-diisocyanate 1,3-phenylene, hexamethylene diisocyanate, 4-methyl-m-phenylene diisocyanate, and diisocyanate. Examples include isophorone.
Examples of the monoalcohol include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol and the like.
Examples of the dialcohols include numerous glycols such as ethylene glycol, diethylene glycol, triethylene glycol, and trimethylene glycol; examples of the trialcohols include trimethylolpropane, triethylolpropane, and trimethanolethane.

  These urethane compounds can be mixed with a resin and a colorant at the time of kneading and used as a kneaded and pulverized toner as in a normal release agent. In addition, when used in the emulsion polymerization aggregation melting toner described above, it is dispersed together with an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base in water, heated to a temperature higher than the melting point, and then a homogenizer or pressure discharge. It can be made into fine particles by applying strong shearing with a mold disperser to prepare a release agent particle dispersion of 1 μm or less, which can be used together with a resin particle dispersion, a colorant dispersion and the like.

-Other components of toner-
The toner may contain other components such as an internal additive, a charge control agent, and inorganic fine particles. As said internal additive, magnetic bodies, such as metals, alloys, such as a ferrite, magnetite, reduced iron, cobalt, nickel, manganese, an alloy, or a compound containing these metals, can be used, for example.

  Examples of the charge control agent include various commonly used charge control agents such as quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments. be able to. A material that is difficult to dissolve in water is preferable from the viewpoint of controlling the ionic strength that affects the stability during aggregation and melting and reducing wastewater contamination.

  As the inorganic fine particles, for example, silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, etc., usually all external additives on the toner surface can be used, and these can be used as ionic surfactants or polymer acids. It is preferable to use it dispersed in a polymer base.

  Furthermore, a surfactant can be used for emulsion polymerization, seed polymerization, pigment dispersion, resin particle dispersion, release agent dispersion, aggregation, and stabilization thereof. For example, anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap, cationic surfactants such as amine salt type and quaternary ammonium salt type, polyethylene glycol type, alkylphenol It is also effective to use a nonionic surfactant such as an ethylene oxide adduct system or a polyhydric alcohol system in combination. As a dispersing means at that time, a general means such as a rotary shear type homogenizer, a ball mill having a media, a sand mill, or a dyno mill can be used.

An external additive may be further added to the toner as necessary. Examples of the external additive include inorganic particles and organic particles. Examples of the inorganic particles include SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , Fe ₂ O ₃ , MgO, BaO, CaO, K ₂ O, Na ₂ O, ZrO ₂ , CaO. Examples thereof include SiO ₂ , K ₂ O. (TiO ₂ ) _n , Al ₂ O ₃ .2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , MgSO _{4 and the} like. Moreover, as said organic particle, fatty acid or its derivative (s), powders, such as these metal salts, resin powders, such as fluorine resin, a polyethylene resin, an acrylic resin, etc. can be used, for example.
For example, the average particle diameter of these particles is preferably 0.01 to 5 μm, and more preferably 0.1 to 2 μm.

  The method for producing the toner is not particularly limited and may be appropriately selected depending on the purpose. (I) A step of forming aggregated particles in a dispersion obtained by dispersing resin particles to prepare an aggregated particle dispersion (Ii) adding and mixing a fine particle dispersion in which fine particles are dispersed in the aggregated particle dispersion to adhere the fine particles to the aggregated particles to form the adhered particles; and (iii) the attached particles. The toner is preferably manufactured by a method for manufacturing a toner comprising a step of heating and coalescing to form toner particles.

-Physical properties of toner-
The volume average particle diameter of the toner of the present invention is preferably from 0.5 μm to 10 μm.
If the volume average particle size of the toner is too small, there may be an adverse effect on toner handling (replenishability, cleaning properties, fluidity, etc.), and particle productivity may be reduced. On the other hand, if the volume average particle diameter of the toner is too large, the image quality and resolution due to graininess and transferability may be adversely affected.
Further, the toner of the present invention preferably satisfies the volume average particle size range of the toner and has a volume average particle size distribution index (GSDv) of 1.3 or less.
The ratio (GSDv / GSDn) of the volume average particle size distribution index (GSDv) to the number average particle size distribution index (GSDn) is preferably 0.95 or more.
In addition, the toner of the present invention satisfies the volume average particle diameter range of the toner, and the average value of the shape factor represented by the following formula is preferably 1.00 to 1.50.
Shape factor = (π × L ² ) / (4 × S)
(However, L represents the maximum length of toner particles, and S represents the projected area of toner particles.)
When the toner satisfies the above conditions, it is effective for image quality, particularly graininess, and resolution, and it is difficult for transfer and omission to occur, and handling properties are not adversely affected even if the average particle size is not small. Become.

The storage modulus G ′ (measured at an angular frequency of 10 rad / sec) at 150 ° C. of the toner itself is 1 × 10 ² to 1 × 10 ⁵ Pa, so that the image quality is improved and the offset property is prevented in the fixing process. It is appropriate from the aspect of

<Silver salt photographic material>
As the silver salt photographic material, for example, a silver halide photographic sheet having a structure in which an image recording layer that develops color at least on YMC is provided on the support for image recording material of the present invention and subjected to printing exposure. Examples of the silver halide photographic system include color development, bleach-fixing, washing with water, and drying by passing through a plurality of processing tanks while immersing.

<Inkjet recording material>
Examples of the ink jet recording material include liquid inks such as water-based inks (using dyes or pigments as coloring materials) and oil-based inks on the support for image recording materials of the present invention, and solids at room temperature. And a colorant receiving layer capable of receiving solid ink or the like that is melted and liquefied and used for printing.

<Thermal transfer material>
The thermal transfer material has, for example, a configuration in which at least a heat-meltable ink layer as an image recording layer is provided on the image-recording material support of the present invention, and is heated by a thermal head to heat-melt ink. Examples include a method in which ink is melt-transferred from a layer onto a thermal transfer sheet.

<Thermal material>
The thermosensitive material is, for example, a thermoauto having a configuration in which at least a thermochromic layer is provided on the image recording material support of the present invention, and forming an image by repeating heating with a thermal head and fixing with ultraviolet rays. Examples thereof include heat-sensitive materials used in the chrome method (TA method).

<Sublimation transfer material>
The sublimation transfer material has, for example, a structure in which an ink layer containing at least a heat diffusible dye (sublimation dye) is provided on the support for image recording material of the present invention, and is heated by a thermal head. And a sublimation transfer method in which a heat-diffusible dye is transferred from an ink layer onto a sublimation transfer sheet.

<Printing paper>
The image recording material support is also preferably used as printing paper. When used as printing paper, a material having high mechanical strength is preferable from the viewpoint of applying ink or the like by a printing machine.

  When a base paper is used as the printing paper, the paper preferably contains a filler, a softening agent, an internal additive for papermaking, and the like. As fillers, commonly used ones can be used, such as clay, calcined clay, diatomaceous earth, talc, kaolin, calcined kaolin, deramikaolin, heavy calcium carbonate, light calcium carbonate, magnesium carbonate, barium carbonate, titanium dioxide. Inorganic fillers such as zinc oxide, silicon oxide, amorphous silica, aluminum hydroxide, calcium hydroxide, magnesium hydroxide, zinc hydroxide, organic fillers such as urea-formalin resin, polystyrene resin, phenol resin, and fine hollow particles , Etc. These may be used alone or in combination of two or more.

  Examples of the internal additive for papermaking include various conventionally used nonionic, cationic, and anionic yield improvers, freeness improvers, paper strength improvers, and internally added sizing agents. Can be mentioned. Specifically, basic aluminum compounds such as sulfate band, aluminum chloride, sodium aluminate, basic aluminum chloride, basic polyaluminum hydroxide; polyvalent metal compounds such as ferrous sulfate and ferric sulfate, starch , Modified starch, polyacrylamide, urea resin, melamine resin, epoxy resin, polyamide resin, polyamine resin, polyamine, polyethyleneimine, vegetable gum, polyvinyl alcohol, latex, polyethylene oxide and other water-soluble polymers, hydrophilic cross-linked polymer particle dispersion Or various compounds such as derivatives or modified products thereof, and these substances simultaneously have some of the functions as an internal additive for papermaking.

  Next, as the functions of the internal sizing agent, the alkyl ketene dimer compound, alkenyl succinic anhydride compound, styrene-acrylic compound, higher fatty acid compound, petroleum resin sizing agent and rosin sizing agent are used. Is mentioned.

  Furthermore, internal additives for papermaking such as dyes, fluorescent brighteners, pH adjusters, antifoaming agents, pitch control agents, slime control agents and the like may be appropriately added depending on the intended use.

  The printing paper is particularly suitable as offset printing paper, and can be used as letterpress printing paper, gravure printing paper, and electrophotographic paper.

  The image recording material of the present invention has a high surface smoothness and an extremely high glossy support for an image recording material, and an image recording layer on the support. It is suitable for any of photographic materials, heat sensitive materials, ink jet recording materials, sublimation transfer materials, silver salt photographic materials, and thermal transfer materials.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention in detail, this invention is not limited to the following Example at all.

(Example 1)
-Preparation of support-
Hardwood bleached kraft pulp (LBKP) was beaten with a disc refiner to 300 ml (Canadian standard freeness, CSF) to prepare a pulp stock having a fiber length of 0.58 mm.
Based on the pulp weight, the pulp stock is based on 1.2% by weight of cationic starch, 0.5% by weight of alkyl ketene dimer (AKD), 0.2% by weight of anionic polyacrylamide, 0.2% of epoxidized fatty acid amide (EFA). It added so that it might become a mass% and the ratio of the polyamide polyamine epichlorohydrin 0.3 mass%. The alkyl portion of the alkyl ketene dimer is derived from a fatty acid mainly composed of behenic acid. The fatty acid portion of the epoxidized fatty acid amide is derived from a fatty acid mainly composed of behenic acid.

A wet paper having an absolute dry weight of 160 g / m ² and a moisture content of 68% was prepared by using a handmade sheet machine for the obtained pulp paper material.
Both sides of the obtained wet paper were sandwiched with filter paper, dehydrated with a wet press device, and the water content was adjusted to 50%.
The wet paper after dehydration was dried using a press-drying apparatus (manufactured by VALMET, Static Condebelt) shown in FIG. 1 to prepare a base paper having a moisture content of 7.0% after drying. In the press drying process, the temperature of the upper plate in contact with the surface side (front surface) on which the image recording layer of the base paper is provided is adjusted to 150 ° C., and the temperature of the lower plate in contact with the surface side (back surface) of the base paper on which the image recording layer is not provided. Was adjusted to 85 ° C. under the conditions of a press pressure of 0.4 MPa and a drying time of 1 second.

Next, 80 parts by mass of calcium carbonate (average particle size 1.9 μm), 20 parts by mass of TiO _2, 25 parts by mass of an acrylic emulsion (glass transition temperature = 65 ° C.), 5 parts by mass of starch, and an appropriate amount of water were mixed. A polymer-containing aqueous coating solution having a solid content of 60% by mass was prepared. The coating solution was applied to the surface of the base paper on the side where the image recording layer is provided by a blade coater so that the solid content was 6 g / m ² .

Next, after the moisture content of the coating layer is set to 20% using a hot air dryer, press drying is performed using the press drying apparatus shown in FIG. 1 to produce a base paper having a moisture content of 7.0% after drying. did. In the press drying process, the temperature of the upper plate in contact with the surface side (front surface) on which the image recording layer of the base paper is provided is adjusted to 110 ° C., and the temperature of the lower plate in contact with the surface side (back surface) on which the image recording layer of the base paper is not provided. Was adjusted to 70 ° C. under the conditions of a press pressure of 0.1 MPa and a drying time of 1 second.
Thereafter, the press-dried base paper is set using a soft calender device on the surface side (surface) on which the image recording layer is provided, the surface temperature of the metal roll having a surface temperature of 190 ° C., and the surface temperature of the resin roll on the opposite side is set to 40 ° C. The calendaring process was performed. The density of the obtained paper as a support was 0.98 g / cm ³ .

(Examples 2 to 4 and Comparative Examples 1 to 5)
In Example 1, except that it changed into the conditions shown in Table 2, it carried out similarly to Example 1, and produced the paper as a support body of Examples 2-4 and Comparative Examples 1-5.

  Next, the gloss, surface flatness, and rigidity of each of the papers (supports) of Examples 1 to 4 and Comparative Examples 1 to 5 obtained were evaluated as follows. The results are shown in Table 3.

<Evaluation of glossiness>
The glossiness of each support was visually observed, and based on the following criteria, the one with the best glossiness was ranked as A, and then ranked as B, C, D, E and evaluated.
〔Evaluation criteria〕
A: Very good.
B: Excellent.
C: Intermediate.
D: Inferior.
E: Very inferior.

<Evaluation of surface smoothness>
Using the surface shape measuring device Surfcom 570A-3DF (manufactured by Tokyo Seimitsu Co., Ltd.), based on the following measurement and analysis conditions, the center plane average on the side where the image recording layer of the support is provided under the conditions of cutoff 5 mm to 6 mm Roughness (SRa) was measured and evaluated according to the following criteria.
-Measurement and analysis conditions-
-Scanning direction: MD direction of the sample-Measurement length: Papermaking (X) direction 50 mm, its vertical (Y) direction 30 mm
・ Measurement pitch: 0.1 mm in the X direction, 0.1 mm in the Y direction
・ Scanning speed: 30mm / sec
・ Band pass filter: 5-6mm
〔Evaluation criteria〕
A: Very good (SRa is 0.3 μm or less).
B: Excellent (SRa is less than 0.5 μm).
C: Intermediate (SRa is 0.5 μm or more and less than 1.0 μm).
D: Inferior (SRa is 1.0 μm or more and less than 2.0 μm).
E: Very inferior (SRa is 2.0 μm or more).

<Rigidity evaluation>
The rigidity (waist) of the obtained support was evaluated according to the evaluation criteria of 1 to 5 based on the feel at the time of tentacles. In addition, it shows that rigidity (waist) is excellent, so that there are many numbers.

(Examples 5-8 and Comparative Examples 6-10)
Using the papers of Examples 1 to 4 and Comparative Examples 1 to 5 (supports for image recording formation), the electrophotographic image receiving papers of Examples 5 to 8 and Comparative Examples 6 to 10 were produced by the following method.

-Titanium dioxide dispersion-
40.0 g of titanium dioxide (Taipaque (registered trademark) A-220, manufactured by Ishihara Sangyo Co., Ltd.), 2.0 g of PVA102 (manufactured by Kuraray Co., Ltd.), and 58.0 g of ion-exchanged water were mixed, and NBK- manufactured by Nippon Seiki Seisakusho Co., Ltd. 2 was used to prepare a titanium dioxide dispersion (content of titanium dioxide pigment was 40% by mass).

-Preparation of coating solution for toner image-receiving layer-
15.5 g of the titanium dioxide dispersion, 15.0 g of carnauba wax dispersion (Cerosol 524, manufactured by Chukyo Yushi Co., Ltd.), 100% polyester resin aqueous dispersion (solid content 30% by mass, KZA-7049, manufactured by Unitika Ltd.) 100 0.0 g, 2.0 g of thickener (Alcox E30, Meisei Chemical Co., Ltd.), 0.5 g of anionic surfactant (AOT), and 80 ml of ion-exchanged water are mixed and stirred to prepare a toner image-receiving layer coating solution. did.
The resulting toner image-receiving layer coating solution had a viscosity of 40 mPa · s and a surface tension of 34 mN / m.

-Preparation of coating solution for back layer-
The following components were mixed and stirred to prepare a back layer coating solution.
Acrylic resin water dispersion (solid content 30% by mass, Hiloss XBH-997L, manufactured by Seiko Chemical Industry Co., Ltd.) 100.0 g, matting agent (Techpomer MBX-12, manufactured by Sekisui Plastics Co., Ltd.) 5.0 g, release A mold (Hydrin D337, manufactured by Chukyo Yushi Co., Ltd.) 10.0 g, a thickener (CMC) 2.0 g, an anionic surfactant (AOT) 0.5 g, and 80 ml of ion-exchanged water are mixed and stirred. A coating solution for the back layer was prepared.
The viscosity of the obtained coating liquid for back layer was 35 mPa · s, and the surface tension was 33 mN / m.

-Coating of back layer and toner image-receiving layer-
On the back surface (surface on the side where the toner image-receiving layer is not provided) of each of the image recording formation supports of Examples 1 to 4 and Comparative Examples 1 to 5, the back layer coating liquid was dried by a bar coater at a dry mass of 9 g / It was applied as a m ^2, and to form a back layer. The toner image-receiving layer coating solution was applied to the surface of each support with a bar coater so that the dry mass was 12 g / m ² , thereby forming a toner image-receiving layer. The pigment content in the toner image-receiving layer was 5% by mass relative to the thermoplastic resin.

The back layer and the toner image receiving layer were coated and then dried online with hot air. In the drying, the drying air volume and temperature were adjusted so that both the back layer and the toner image-receiving layer were dried within 2 minutes after coating. The drying point was the point at which the coating surface temperature was the same as the wet bulb temperature of the drying air.
Next, after drying, a calendar process was performed. The calendering process was performed under the condition of a nip pressure of 14.7 kN / cm ² (15 kgf / cm ² ) using a gloss calender and keeping the metal roller at 40 ° C.

Each obtained electrophotographic image receiving paper was cut into A4 size, and an image was printed using an electrophotographic printer. As the printer used, a color laser printer (DocuColor 1250-PF) manufactured by Fuji Xerox Co., Ltd., having the fixing unit shown in FIG. 3 as the belt fixing device 1 was used.
That is, in the belt fixing device 1 shown in FIG. 3, the fixing belt 2 is suspended over the heating roller 3 and the tension roller 5, and the cleaning roller 6 is disposed above the tension roller 5 via the fixing belt 2. Further, a pressure roller 4 is provided below the heating roller 3 via the fixing belt 2. The electrophotographic image-receiving paper having the latent toner image is inserted between the heating roller 3 and the pressure roller 4 from the right side in FIG. 3 and fixed, and then moved on the fixing belt 2. In the process, it is cooled by the cooling device 7 and finally cleaned by the cleaning roller 6.
In the belt fixing device 1, the conveyance speed of the fixing belt 2 is 30 mm / second, the nip pressure between the heating roller 3 and the pressure roller 4 is 0.2 MPa (2 kgf / cm ² ), The set temperature of the heating roller 3 is 150 ° C., which corresponds to the fixing temperature. The set temperature of the pressure roller 4 was set to 120 ° C.

  Each obtained electrophotographic print was evaluated for image quality, glossiness and rigidity as follows. The results are shown in Table 4.

<Image quality>
The image quality of each electrophotographic print was visually observed, and the best image quality was ranked as A and then evaluated as B, C, D, E based on the following criteria.
〔Evaluation criteria〕
A ... Excellent (effective as a high-quality recording material)
B ... Excellent (effective as a high-quality recording material)
C ・ ・ ・ Intermediate (impossible as a high-quality recording material)
D: Inferior (not possible as a high-quality recording material)
E ... Very inferior (impossible as high quality recording material)

<Glossiness>
The glossiness of each electrophotographic print was visually observed, and the best glossiness was ranked as A and then evaluated as B, C, D, E based on the following criteria.
〔Evaluation criteria〕
A ... Excellent (effective as a high-quality recording material)
B ... Excellent (effective as a high-quality recording material)
C ・ ・ ・ Intermediate (impossible as a high-quality recording material)
D: Inferior (not possible as a high-quality recording material)
E ... Very inferior (impossible as high quality recording material)

<Rigidity>
The rigidity (waist) of each electrophotographic print obtained was evaluated according to the evaluation criteria of 1 to 5 by the feel at the time of tentacles. In addition, it shows that rigidity (waist) is excellent, so that there are many numbers.

(Examples 9-12 and Comparative Examples 11-15)
-Photographic paper-
Gelatin 0.1 g / m ² was applied, to the gelatin coated surface to the surface on the side of providing the image recording layer of the image recording support prepared in Examples 1-4 and Comparative Example 1-5 (surface) Yellow-colored color silver halide gelatin emulsion layer (10 g / m ² ), gelatin intermediate layer, magenta color-colored silver halide gelatin emulsion layer (10 g / m ² ), gelatin intermediate layer, cyan-colored color photographic halogen A silver halide gelatin emulsion layer (10 g / m ² ) and a gelatin protective layer were coated in this order to produce photographic papers of Examples 9 to 12 and Comparative Examples 11 to 15.

  Each obtained photographic printing paper was exposed and developed to obtain a photographic print. The surface smoothness (fine irregularities (1 mm or less)) and surface smoothness (waviness irregularities (5 to 6 mm)) of the screen of each photographic print were evaluated by the following methods. The results are shown in Table 5.

<Surface smoothness (micro unevenness (1 mm or less)>
Each photographic print was visually observed, and based on the following criteria, the best surface smoothness (small unevenness (1 mm or less)) was rated as A, and then ranked as B, C, D, E and evaluated. .
〔Evaluation criteria〕
A ... Excellent (effective as a high-quality recording material)
B ... Excellent (effective as a high-quality recording material)
C ・ ・ ・ Intermediate (impossible as a high-quality recording material)
D: Inferior (not possible as a high-quality recording material)
E ... Very inferior (impossible as high quality recording material)

<Surface smoothness (undulation unevenness (5 to 6 mm)>
Each photographic print was visually observed, and based on the following criteria, the best surface smoothness (waviness unevenness (5-6 mm)) was ranked as A, then B, C, D, E, and evaluated. did.
〔Evaluation criteria〕
A ... Excellent (effective as a high-quality recording material)
B ... Excellent (effective as a high-quality recording material)
C ・ ・ ・ Intermediate (impossible as a high-quality recording material)
D: Inferior (not possible as a high-quality recording material)
E ... Very inferior (impossible as high quality recording material)

  The paper of the present invention is excellent in smoothness and gloss, and can be widely used as various image recording materials such as electrophotographic materials, heat sensitive materials, ink jet recording materials, sublimation transfer materials, silver salt photographic materials, thermal transfer materials and the like.

FIG. 1 is a schematic view showing an example of a press dry processing apparatus of the present invention. FIG. 2 is a schematic view showing an example of a press drying apparatus when the press drying process of the present invention is performed as a production line. FIG. 3 is a schematic configuration diagram of a belt fixing device in the image forming apparatus used in the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Belt fixing device 2 Fixing belt 3 Heating roller 4 Pressure roller 5 Tension roller 6 Cleaning roller 7 Cooling device 38 Endless belt 39 Endless belt 40 Pulp stock 41 Fabric 42 Upper plate 43 Lower plate 44 Jacket 45 Hydraulic oil 46 Cooling water 47 oil for heating 48 pressurizer 49 vacuum tank 51 first rotating roller 52 first rotating roller 53 second rotating roller 54 second rotating roller 55 heat chamber 56 cooling chamber 100 press drying device 200 press drying device

Claims (12)

  A paper having a base paper and a polymer-containing layer on at least a surface of the base paper on which an image recording layer is provided, wherein the paper is subjected to a pressure drying process.   The paper according to claim 1, wherein the base paper is a base paper obtained by subjecting wet paper to pressure drying treatment.   The paper according to any one of claims 1 to 2, wherein the polymer-containing layer contains at least one of a water-soluble polymer and a water-dispersible polymer emulsion.   The paper according to any one of claims 1 to 3, wherein the polymer-containing layer contains a pigment.   A polymer-containing layer forming step of forming a polymer-containing layer on at least the image recording layer side of the base paper, and a pressure-drying processing step of pressure-drying the base paper having the polymer-containing layer. Paper manufacturing method.   The paper manufacturing method according to claim 5, wherein calendering is performed after the pressure drying treatment step.   The paper manufacturing method according to any one of claims 5 to 6, wherein a polymer-containing layer forming step is performed on a base paper obtained by subjecting wet paper to pressure drying treatment.   The paper manufacturing method according to any one of claims 5 to 7, wherein the moisture content in the polymer-containing layer is dried until the water content becomes 5 to 30%, and then subjected to pressure drying treatment.   The paper manufacturing method according to any one of claims 5 to 8, wherein a press pressure in the pressure drying treatment is 0.05 to 0.5 MPa.   A support for an image recording material comprising the paper according to claim 1.   An image recording material comprising a support and at least an image recording layer on the support, wherein the support is the support for an image recording material according to claim 10. The image recording material according to claim 11, which is selected from electrophotographic materials, heat-sensitive materials, ink jet recording materials, sublimation transfer materials, silver salt photographic materials, and thermal transfer materials.

Images