JP2005181884A - Electrophotographic image receiving sheet and image formation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic image receiving sheet that ensures satisfactory toner fixability and the formation of a high quality image in which the glossiness in particular of intermediate density is improved, and to provide an image formation method that uses the electrophotographic image receiving sheet. <P>SOLUTION: The electrophotographic image receiving sheet has a support and a toner image receiving layer which is formed on the support and contains at least thermoplastic resin. The Cobb water absorbancy of the surface of the electrophotographic image receiving sheet on the toner image receiving layer side is 1 to 20 g/m<SP>2</SP>. The toner receiving layer preferably contains a water soluble resin, which is preferably polyethylene oxide. The image forming method uses the electrophotographic image receiving sheet. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrophotographic image-receiving sheet and an image forming method, and relates to an electrophotographic image-receiving sheet capable of forming a high-quality image having good toner fixing properties and particularly improved glossiness at an intermediate density. The present invention relates to an image forming method using a sheet.

  Conventionally, the electrophotographic method has been used for copiers and PC output machines because it can be printed on general-purpose paper (plain paper or high-quality paper) by dry processing and has a high printing speed. When image information such as image data is output as a photograph, special-purpose paper for photographic use is required because general-purpose paper or the like is particularly inferior in gloss or feels different from a photograph.

In order to meet the above requirements and obtain a special paper having excellent gloss, an electrophotographic image-receiving sheet provided with a toner image-receiving layer containing a thermoplastic resin on a support has been proposed (see, for example, Patent Documents 1 and 2). ). Furthermore, in order to make the feel closer to a photograph, Patent Document 2 proposes an electrophotographic image receiving sheet using a support provided with a thermoplastic resin layer on the front and back surfaces of a base paper.
Further, Patent Document 3 discloses that in an electrophotographic image forming apparatus that uses electrophotographic image receiving paper (transfer paper) that has been regenerated by removing toner, the transfer current of the recycled paper or the heat supplied to the fixing unit is controlled. Although it is described that the moisture content of the transfer paper is related to the toner adhesion amount, there is no suggestion about the moisture content and toner fixability.
Patent Document 4 proposes an electrophotographic image-receiving sheet excellent in heat resistance in which a heat-resistant layer made of a hydrophilic resin is provided on the back surface opposite to the toner image-receiving layer. No relationship is disclosed or suggested.

  Therefore, in the electrophotographic image-receiving sheet, no proposal has been made focusing on the water absorption in the toner image-receiving layer, and there has not yet been provided a sheet having good fixability and particularly improved intermediate glossiness. It is.

JP-A-4-212168 Japanese Patent Laid-Open No. 8-21645 JP-A-7-239629 JP 2000-3062 A

  This invention is made | formed in view of this present condition, and makes it a subject to solve the said problem in the past and to achieve the following objectives. That is, the present invention relates to an electrophotographic image-receiving sheet capable of forming a high-quality image having good toner fixing properties and particularly improved intermediate density glossiness, and an image forming method using the electrophotographic image-receiving sheet. The purpose is to provide.

Means for solving the problems are as follows. That is,
<1> An electrophotographic image-receiving sheet having a support and a toner image-receiving layer containing at least a thermoplastic resin on the support, the bump water absorption on the surface of the electrophotographic image-receiving sheet on the toner image-receiving layer side An electrophotographic image-receiving sheet having a degree of 1 to 20 g / m ² .
<2> The electrophotographic image-receiving sheet according to <1>, wherein the water absorption of the bumps is ² to 15 g / m ² .
<3> The electrophotographic image-receiving sheet according to any one of <1> to <2>, wherein the toner image-receiving layer contains a water-soluble resin.
<4> The electrophotographic image-receiving sheet according to <3>, wherein the water-soluble resin is at least one selected from a polyalkylene oxide resin, an ester ether resin, and an aqueous nylon resin.
<5> The electrophotographic image-receiving sheet according to any one of <1> to <4>, wherein the support is selected from base paper, synthetic paper, synthetic resin sheet, coated paper, and laminated paper.
<6> A toner image forming step of forming a toner image on the electrophotographic image-receiving sheet according to any one of <1> to <5>, a heating and pressing member, a belt member, and a cooling device for the toner image And a fixing and smoothing step of heating and pressurizing, cooling and peeling using a belt fixing type smoothing processor.
<7> The image forming method according to <6>, wherein the toner image forming step includes a toner image fixing step of fixing the toner image formed on the electrophotographic image receiving sheet with a heat roller.
<8> The method according to any one of <6> to <7>, wherein in the fixing smoothing step, the toner image surface is heated and pressurized to a temperature of 80 ° C. or higher and lower than 180 ° C., and is peeled from the belt member at a temperature of 80 ° C. or lower. This is an image forming method.
<9> The image forming method according to any one of <6> to <8>, wherein the belt member has a fluorocarbon siloxane rubber layer formed on a belt support.
<10> The image forming method according to any one of <6> to <8>, wherein the belt member includes a silicone rubber layer formed on a belt support and a fluorocarbonsiloxane rubber layer formed on the surface of the silicone rubber layer. .
<11> The image forming method according to any one of <9> to <10>, wherein the fluorocarbon siloxane rubber in the fluorocarbon siloxane rubber layer has at least one of a perfluoroalkyl ether group and a perfluoroalkyl group in a main chain. is there.

The electrophotographic image-receiving sheet of the present invention has a support and a toner image-receiving layer containing at least a thermoplastic resin on the support, and the bump water absorption on the surface of the electrophotographic image-receiving sheet on the toner image-receiving layer side. The degree is 1 to 20 g / m ² . As a result, the toner image-receiving layer has water absorption and contains appropriate moisture, so that the toner fixing property is improved, and in particular, an image receiving sheet for electrophotography capable of forming a high-quality image with improved intermediate density glossiness. Is obtained.

  The image forming method of the present invention is a method of forming an image by an oil-less method using the electrophotographic image receiving sheet of the present invention, and after forming a toner image, the image forming surface of the electrophotographic image receiving sheet Is heated and pressed by a fixing belt and a fixing roller, cooled, and then peeled off from the fixing belt. As a result, even if an oilless machine without fixing oil is used, it is possible to prevent the peeling of the electrophotographic image receiving sheet and toner, or the offset of the image receiving sheet and toner component, to realize stable paper feeding and toner fixing. Therefore, it is possible to realize a good image that is rich in photographic feeling and improved in glossiness at an intermediate density.

  According to the present invention, it is possible to provide an electrophotographic image-receiving sheet that can solve various problems in the prior art, can form a high-quality image with good toner fixing properties, and particularly improved glossiness at an intermediate density.

(Electrophotographic image-receiving sheet)
The electrophotographic image-receiving sheet in the present invention has a support and a toner image-receiving layer containing at least a thermoplastic resin on the support, and other layers appropriately selected as necessary, for example, a protective layer, It comprises an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflection layer, a tint preparation layer, a storage stability improving layer, an adhesion prevention layer, an anti-curl layer, a smoothing layer and the like. Each of these layers may have a single layer structure or a laminated structure.

In the present invention, the water absorption on the toner image-receiving layer side of the electrophotographic image-receiving sheet (that is, the surface of the toner image-receiving layer) is 1 to 20 g / m ² , and preferably ² to 15 g / m ² .
As described above, the toner image-receiving layer containing at least the thermoplastic resin in the electrophotographic image-receiving sheet has a certain level of water absorption, so that the toner fixing property is improved, and particularly the glossiness at an intermediate density is improved. This can also be confirmed from the fact that in the examples described later, the glossiness under an environment of 23 ° C. and 85% RH (high humidity) is higher than the glossiness under an environment of 23 ° C. and 50% RH.
When the bump water absorption is less than 1 g / m ² , the fixability is poor and the glossiness decreases, and when it exceeds 20 g / m ² , the blocking resistance deteriorates.
Here, the degree of sizing of the bumps is measured by a water absorption test based on the degree of sizing of the stipulated in JIS P 8140. Specifically, the degree of bump sizing is a measure of the amount of water absorbed when pure water is brought into contact with the surface on the toner image-receiving layer side of the electrophotographic image-receiving sheet (that is, the surface of the toner image-receiving layer) for 300 seconds.

  The bump water absorption is a content of a thermoplastic resin (particularly, a water-soluble resin), a surfactant, an inorganic salt, etc. of a toner image-receiving layer containing at least a thermoplastic resin in the electrophotographic image-receiving sheet described later. It is controlled by adjusting.

[Support]
Examples of the support include base paper, synthetic paper, synthetic resin sheet, coated paper, and laminated paper. These supports may have a single layer structure or a laminated structure of two or more layers. Among these, laminated paper in which one or both sides are coated with a polyolefin resin layer is preferable in terms of smooth glossiness and stretchability.

-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, Ltd. The paper etc. of a corona company publication (Showa 54) (223)-(240) page are mentioned as a suitable thing.

  The material of the base paper is not particularly limited as long as it is a known material used for an electrophotographic image-receiving sheet, and can be appropriately selected from various materials according to the purpose. For example, softwood, hardwood, etc. Examples include natural pulp, synthetic pulp made of synthetic resin such as polyethylene and polypropylene, or a mixture of natural 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, alkyl ketene dimer, alkenyl succinic anhydride (ASA), and epoxidized fatty acid amide.
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.

There is no restriction | limiting in particular in the process liquid used for the said surface size process, According to the objective, it can select suitably, For example, a water-soluble polymer compound, a water-resistant substance, a pigment, dye, fluorescent whitening agent, etc. 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; polyamide polyamine epichlorohydrin, and the like.
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 above 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.

-Synthetic paper-
The synthetic paper is paper mainly composed of polymer fibers other than cellulose, and examples of the polymer fibers include polyolefin fibers such as polyethylene and polypropylene.

-Synthetic resin sheet (film)-
Examples of the synthetic resin sheet (film) include those obtained by forming a synthetic resin into a sheet shape. For example, a polypropylene film, a stretched polyethylene film, a stretched polypropylene, a polyester film, a stretched polyester film, a nylon film, and whitened by stretching. And a white film containing a white pigment.

-Coated paper-
The coated paper is a paper obtained by coating various sheets of resin, rubber latex, or polymer material on one side or both sides of a sheet such as a base paper, and the coating amount varies depending on the application. Examples of such coated paper include art paper, cast coated paper, Yankee paper, and the like.

  As the resin applied to the surface of the base paper or the like, it is appropriate to use a thermoplastic resin. Examples of such a thermoplastic resin include the following thermoplastic resins (a) to (h).

(A) Polyolefin resins such as polyethylene resins and polypropylene resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, acrylic resins, and the like.
(B) A thermoplastic resin having an ester bond. For example, a dicarboxylic acid component (these dicarboxylic acid components may be substituted with a sulfonic acid group, a carboxyl group, etc.) and an alcohol component (these alcohol components may be substituted with a hydroxyl group, etc.) Polyester resin, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate and other polyacrylic acid ester resins or polymethacrylic acid ester resins, polycarbonate resins, polyvinyl acetate resins, styrene acrylate resins, styrene -Methacrylic acid ester copolymer resin, vinyl toluene acrylate resin, etc. are mentioned.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7973, and 60-294862. it can.
Commercially available products include Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130 manufactured by Toyobo; Kao-made Tufton NE-382, Tufton U-5, ATR- 2009, ATR-2010; Unitika's Elitel UE3500, UE3210, XA-8153, KZA-7049, KZA-1449; Nippon Synthetic Chemical Polyester TP-220, R-188; And various thermoplastic resins.

(C) Polyurethane resin etc. are mentioned.
(D) Polyamide resin, urea resin, etc. are mentioned.
(E) Polysulfone resin and the like.
(F) Polyvinyl chloride resin, polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, and the like.
(G) Cellulose resins, such as polyol resin, ethyl cellulose resin, cellulose acetate resin, etc., such as polyvinyl butyral.
(H) Polycaprolactone resin, styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin and the like.
In addition, the said thermoplastic resin may be used individually by 1 type, and may use 2 or more types together.

  Further, the thermoplastic resin may contain pigments or dyes such as brighteners, conductive agents, fillers, titanium oxide, ultramarine blue, and carbon black as required.

-Laminated paper-
The laminated paper is a paper obtained by laminating various resins, rubber or polymer sheets or films on a sheet such as a base paper. Examples of the laminate material include polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, polymethacrylate, polycarbonate, polyimide, triacetyl cellulose, and the like. These resins may be used alone or in combination of two or more.

  In general, the polyolefin is often formed using low density polyethylene, but in order to improve the heat resistance of the support, polypropylene, a blend of polypropylene and polyethylene, high density polyethylene, high density polyethylene and low density polyethylene, It is preferable to use a blend of In particular, it is most preferable to use a blend of high-density polyethylene and low-density polyethylene from the viewpoint of cost, suitability for lamination, and the like.

The blend of the high density polyethylene and the low density polyethylene is used, for example, in a blend ratio (mass ratio) of 1/9 to 9/1. The blend ratio is preferably 2/8 to 8/2, and more preferably 3/7 to 7/3. When forming a thermoplastic resin layer on both surfaces of the support, the back surface of the support is preferably formed using, for example, high-density polyethylene or a blend of high-density polyethylene and low-density polyethylene. The molecular weight of polyethylene is not particularly limited, but the melt index is 1.0 to 40 g / 10 min for both high-density polyethylene and low-density polyethylene and has extrudability. preferable.
In addition, you may perform the process which gives white reflectivity to these sheets or films. Examples of such a treatment method include a method of blending a pigment such as titanium oxide in these sheets or films.

  The thickness of the support is preferably 25 μm to 300 μm, more preferably 50 μm to 260 μm, and still more preferably 75 μm to 220 μm. Various types of stiffness can be used according to the purpose of the support, and the support for a photographic image receiving sheet for electrophotography is close to a support for color silver salt photography. Those are preferred.

[Toner image receiving layer]
The toner image receiving layer is a toner image receiving layer for receiving color 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 made of a material containing at least a thermoplastic resin and optionally added for the purpose of improving the thermodynamic properties of the toner image-receiving layer, such as a surfactant and a release agent. , Plasticizers, colorants, fillers, crosslinking agents, charge control agents, and other components.

-Thermoplastic resin-
The thermoplastic resin is not particularly limited as long as it can be deformed under temperature conditions such as fixing and can accept the toner, and can be appropriately selected according to the purpose. And a copolymer resin such as polyester resin, styrene, styrene-butyl acrylate, etc., and preferably contains 20% by mass or more of a copolymer resin such as polyester resin, styrene, styrene-butyl acrylate. Is more preferable. Further, styrene, styrene-butyl acrylate copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer and the like are more preferable.

  Examples of the thermoplastic resin include (a) a resin having an ester bond, (b) a polyurethane resin, (c) a polyamide resin, (d) a polysulfone resin, (e) a polyvinyl chloride resin, etc. ) Polyvinyl butyral, (to) polycaprolactone resin, (h) polyolefin resin, and the like.

Examples of the resin having an ester bond (b) include terephthalic acid, isophthalic acid, maleic acid, fumaric acid, phthalic acid, adipic acid, sebacic acid, azelaic acid, abietic acid, succinic acid, trimellitic acid, and pyromellitic acid. Dicarboxylic acid components such as acids (these dicarboxylic acid components may be substituted with sulfonic acid groups, carboxyl groups, etc.) and diether derivatives of ethylene glycol, diethylene glycol, propylene glycol, bisphenol A, bisphenol A (for example, Bisphenol A ethylene oxide 2 adducts, bisphenol A propylene oxide 2 adducts, etc.), bisphenol S, 2-ethylcyclohexyldimethanol, neopentyl glycol, cyclohexyldimethanol, glycerin, etc. Polyacrylic acid ester resins such as polyester resins, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate, etc. obtained by condensation with the alcohol component (these alcohol components may be substituted with hydroxyl groups, etc.) Alternatively, polymethacrylic acid ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, styrene-methacrylic acid ester copolymer resin, vinyl toluene acrylate resin, and the like can be given.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862.

Examples of commercially available polyester resins include Toyobo's Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130; Kao's Tufton NE-382, Tufton U- 5, ATR-2009, ATR-2010; Elitel UE3500, UE3210, XA-8153 manufactured by Unitika; Polyester TP-220, R-188 manufactured by Nippon Synthetic Chemical Co., Ltd.
Commercially available products of the acrylic resin include Mitsubishi Rayon Co., Ltd. Dianal SE-5437, SE-5102, SE-5377, SE-5649, SE-5466, SE-5482, HR-169, 124, HR-1127. , HR-116, HR-113, HR-148, HR-131, HR-470, HR-634, HR-606, HR-607, LR-1065, 574, 143, 396, 637, 162, 469, 216 , BR-50, BR-52, BR-60, BR-64, BR-73, BR-75, BR-77, BR-79, BR-80, BR-83, BR-85, BR-87, BR -88, BR-90, BR-93, BR-95, BR-100, BR-101, BR-102, BR-105, BR-106, BR-107, BR- 08, BR-112, BR-113, BR-115, BR-116, BR-117; Sreck P SE-0020, SE-0040, SE-0070, SE-0100, SE-1010, SE- manufactured by Sekisui Chemical Co., Ltd. 1035; Sanyo Chemical Industries Himer ST95, ST120; FM601 manufactured by Mitsui Chemicals.

Examples of the (e) polyvinyl chloride resin include polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, and the like.
Examples of the (f) polyvinyl butyral include cellulose resins such as polyol resin, ethyl cellulose resin, and cellulose acetate resin. Examples of commercially available products include those manufactured by Denki Kagaku Kogyo Co., Ltd. and Sekisui Chemical Co., Ltd. The polyvinyl butyral has a polyvinyl butyral content of 70% by mass or more, an average polymerization degree of 500 or more is preferable, an average polymerization degree of 1000 or more is more preferable, and a commercial product is Denka Butyral manufactured by Denki Kagaku Kogyo Co., Ltd. 3000-1, 4000-2, 5000A, 6000C; manufactured by Sekisui Chemical Co., Ltd. S-REC BL-1, BL-2, BL-3, BL-S, BX-L, BM-1, BM-2, BM-5 , BM-S, BH-3, BX-1, BX-7, and the like.
Examples of the (g) polycaprolactone resin include styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin, and the like.
Examples of the (h) polyolefin resin include polyethylene resins, polypropylene resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, acrylic resins, and the like.

  The said thermoplastic resin may be used individually by 1 type, may be 2 or more types, In addition to these, these mixtures, these copolymers, etc. can also be used.

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

  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 necessarily preferable depending on the relationship between the thermodynamic properties of the thermoplastic resin used in the toner and the resin used in the toner image-receiving layer. For example, when the softening temperature of the resin used in the toner image receiving layer is higher than that of the thermoplastic resin used in the toner, the molecular weight is the same or the resin used in the toner image receiving layer is the same. Smallness may be preferred.

It is also preferable to use a mixture of resins having the same composition and different average molecular weights as the thermoplastic resin. 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 is preferably wider than the molecular weight distribution of the thermoplastic resin used in the toner.
Examples of the thermoplastic resin include JP-A-5-127413, JP-A-8-194394, JP-A-8-334915, JP-A-8-334916, JP-A-9-171265, and JP-A-10. Those satisfying the physical properties disclosed in the publication No. 221877 / etc. Are preferred.

The thermoplastic resin used in the toner image-receiving layer is particularly preferably an aqueous resin such as a water-soluble resin or a water-dispersible resin for the following reasons (i) to (ii).
(I) The organic solvent is not discharged in the coating and drying process, and is excellent in environmental suitability and work suitability. (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. Further, the water dispersion form is more stable and more suitable for the production process. Furthermore, the water-based coating is more likely to cause the wax to bleed onto the surface during the coating and drying process, and the effects of the release agent (offset resistance, adhesion resistance, etc.) can be easily obtained.

  If it is water-soluble resin or water-dispersible resin as said water-based resin, the composition, bond structure, molecular structure, molecular weight, molecular weight distribution, and form will not be specified. 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, or an ether group.

In the present invention, it is preferable to add a water-soluble resin to the toner image-receiving layer in order to adjust the bump water absorption.
The water-soluble resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, Research Disclosure No. 17,643, page 26, No. 18,716, page 651, No. 307,105 Pp. 873-874 and JP-A-64-13546, pages (71)-(75).
The water-soluble resin is preferably at least one selected from polyalkylene oxide resins, ester ether resins and aqueous nylon resins.
Specifically, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, cellulose sulfate, polyethylene oxide, gelatin, cationized starch, casein, sodium polyacrylate, styrene-maleic anhydride copolymer sodium salt, polystyrene Sodium sulfonate, vinyl pyrrolidone-vinyl acetate copolymer, styrene-vinyl pyrrolidone copolymer, styrene-maleic anhydride copolymer, water-soluble polyester, water-soluble acrylic, water-soluble polyurethane, water-soluble nylon, water-soluble epoxy resin , Etc. The gelatin may be selected from so-called demineralized gelatin with a reduced content of lime-processed gelatin, acid-processed gelatin, calcium, etc., depending on various purposes, and is preferably used in combination. Among these, polyethylene oxide is preferable.
Commercially available products of the water-soluble resin include various plus coats manufactured by Tateo Chemical Industry Co., Ltd. as water-soluble polyesters; Finetex ES series manufactured by Dainippon Ink &Chemicals; Jurimer AT series manufactured by Nippon Pure Chemical Co., Ltd. as water-soluble acrylics; Dai Nippon Ink Chemical Co., Ltd. Finetex 6161, K-96; Seiko Chemical Industries high loss NL-1189, BH-997L; polyethylene oxide, Alcox series manufactured by Meisei Chemical Industry Co., Ltd .; Paogen manufactured by Pharmaceutical Co., Ltd .; AQ-nylon manufactured by Toray Industries, Inc. as an aqueous nylon resin.
The polyethylene oxide has a weight average molecular weight (Mw) of preferably 400,000 or less, more preferably 100,000 to 400,000.
The content of the water-soluble resin in the toner image-receiving layer is preferably 0.5 to ² g / m ² . The content of the water-soluble resin is important in adjusting the water absorption of the bumps. If the content is too large, the water absorption of the bumps may be too large, and if it is too small, the water absorption of the bumps may be reduced.

Examples of the water-dispersible resin include water-dispersed resins such as water-dispersed acrylic resins, water-dispersed polyester resins, water-dispersed polystyrene resins, and water-dispersed urethane resins; acrylic resin emulsions, polyvinyl acetate emulsions, and SBR (styrene. (Butadiene / rubber) Emulsions such as emulsions, resins and emulsions in which the thermoplastic resins (a) to (h) above are dispersed in water, or copolymers, mixtures, and cationically modified ones, as appropriate. And two or more can be combined.
Commercially available products of the water-dispersible resin include, for example, Toyobo's Bironal series, Takamatsu Yushi pesresin A series, Kao Tufton UE series, Nippon Synthetic Polyester WR series, Unitika Eliere series, and acrylic series. Then, high loss XE, KE, PE series manufactured by Seiko Chemical Industry, Jurimer ET series manufactured by Nippon Pure Chemical Co., Ltd. and the like can be mentioned.

The film forming temperature (MFT) of the thermoplastic resin to be used is preferably room temperature or higher for storage before printing, and preferably 100 ° C. or lower for fixing toner particles.
The content of the thermoplastic resin in the toner image-receiving layer is preferably 50% by mass or more, and more preferably 50 to 90% by mass.

-Surfactant-
The surfactant is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably an anionic surfactant, for example, higher alcohol sulfate salts, fatty acid amide sulfonates, and the like. Representative examples include sodium linear alkylbenzene sulfonate having a saturated or unsaturated alkyl group having 8 to 22 carbon atoms.
The content of the surfactant in the toner image-receiving layer is preferably from 0.01 to 1.0 g / m ² .

-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 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 a layer of the release agent material on the surface of the toner image receiving layer. As long as it forms, the kind is not limited.
Examples of the release agent exhibiting such effects include at least one release agent selected from silicone compounds, fluorine compounds, waxes, and matting agents. Preferably, at least one release agent selected from the group consisting of silicone oil, polyethylene wax, carnauba wax, and silicone particles and polyethylene wax particles is used.

  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. JP-B-59-38581, JP-B-4-32380, Patent Nos. 2838498, 2949558, JP-A-50-117433, 52-52640, 57-148755, 61-62056. 61-62057, 61-118760, JP-A-2-42451, 3-41465, 4-212175, 4-214570, 4-263267, 5-34966, 5-119514, 6-59502, 6-161150, 6-175396, 6-219040, 6-230600, 6-295093, 7-36210, 7 -43940, 7-56387, 7-56390, 7-64335, 7-199682, 7-223362 7-287413, 8-184992, 8-227180, 8-248671, 8-248799, 8-248801, 8-278663, 9-152939, 9 -160278, 9-185181, 9-319139, 9-319143, 10-20549, 10-48889, 10-198069, 10-207116, 11-2917 No. 11-44969, No. 11-65156, No. 11-73049, No. 11-194542, and the silicone compounds, fluorine compounds, and waxes used in the toners are also preferably used. . Further, a plurality of these compounds can be used in combination.

  Specifically, as the silicone compound, unmodified silicone oil as silicone oil (specifically, dimethylsiloxane oil, methyl hydrogen silicone oil, phenylmethyl silicone oil, commercially available KF-96 manufactured by Shin-Etsu Chemical Co., Ltd.) KF-96L, KF-96H, KF-99, KF-50, KF-54, KF-56, KF-965, KF-968, KF-994, KF-995, HIVAC F-4, F-5; Toray Dow Corning Silicone SH200, SH203, SH490, SH510, SH550, SH710, SH704, SH705, SH7028A, SH7036, SM7060, SM7001, SM7706, SH7036, SH8710, SH1107, SH8627; Toshiba Silicone TSF400, TSF401, TSF404, TSF405, TSF431, TSF433, TSF434, TSF437, TSF450 series, TSF451 series, TSF456, TSF458 series, TSF483, TSF484, TSF4045, TSF4300, TSF4600, YF33 series, YF-3057, YF-3057 3802, YF-3804, YF-3807, YF-3897, XF-3905, XS69-A1753, TEX100, TEX101, TEX102, TEX103, TEX104, TSW831, etc., amino-modified silicone oil (KF manufactured by Shin-Etsu Chemical Co., Ltd. as a commercial product) -857, KF-858, KF-859, KF-861, KF-864, KF-880, Toray Dowconi SF8417, SM8709 made by Ning Silicone, TSF4700, TSF4701, TSF4702, TSF4703, TSF4704, TSF4705, TSF4706, TEX150, TEX151, TEX154, etc. made by Toshiba Silicone, carboxy-modified silicone oil (Toray Dow Corning Silicone BY16- as a commercial product) 880, Toshiba Silicone TSF4770, XF42-A9248, etc.), carbinol modified silicone oil (Toshiba Silicone XF42-B0970 etc. as a commercial product), vinyl modified silicone oil (Toshiba Silicone XF40-A1987 etc. as a commercial product), epoxy modified Silicone oil (Toray Dow Corning Silicone SF8411, SF8413 as a commercial product; Toshiba Silico TSF3965, TSF4730, TSF4732, XF42-A4439, XF42-A4438, XF42-A5041, XC96-A4462, XC96-A4463, XC96-A4464, TEX170, etc., polyether-modified silicone oil (KF made by Shin-Etsu Chemical) -351 (A), KF-352 (A), KF-353 (A), KF-354 (A), KF-355 (A), KF-615 (A), KF-618, KF-945 (A ); Toray Dow Corning Silicone SH3746, SH3771, SF8421, SF8419, SH8400, SF8410; Toshiba Silicone TSF4440, TSF4441, TSF4445, TSF4446, TSF4450, TSF4452, TSF4453, SF4460), silanol-modified silicone oil, methacryl-modified silicone oil, mercapto-modified silicone oil, alcohol-modified silicone oil (Toray Dow Corning Silicone SF8427, SF8428, Toshiba Silicone TSF4750, TSF4751, XF42-B0970, etc.) , Alkyl-modified silicone oils (Toray Dow Corning Silicone SF8416, Toshiba Silicone TSF410, TSF411, TSF4420, TSF4421, TSF4422, TSF4450, XF42-334, XF42-A3160, XF42-A3161, etc.), fluorine-modified silicone Oil (commercially available FS1265 made by Toray Dow Corning Silicone, Toshiba Silicone FQF501, etc.), silicone rubber and silicone fine particles (Toray Dow Corning Silicone SH851U, SH745U, SH55UA, SE4705U, SH502UA & B, SRX539U, SE6770U-P, DY38-038, DY38-047, Trefill F-201, F-202, F-250, R-900, R-902A, E-500, E-600, E-601, E-506, BY29-119; Toshiba Silicone Tospearl 105, 120, 130, 145, 240, 3120), silicone-modified resins (specifically, olefin resins, polyester resins, vinyl resins, polyamide resins, cellulose resins, phenoxy resins, vinyl chloride-vinyl acetate resins, urethane resins, acrylic resins, styrene resins) Dairy Seika's Dialomer SP203V, SP712, SP2105, SP3023; Nippon Oil & Fats Modiper FS700, FS710, FS720, FS730, FS770; Toa Gosei Chemical Co., Ltd. Symac US-270, US-350, US-352, US-380, US-413, US-450, Reseda GP-705, GS-30, GF-150, GF-300; SH997 manufactured by Toray Dow Corning Silicone SR2114, SH2104, SR2115, SR2202, DCI-2577, SR2317, SE4001U, SRX625B, SRX643, SRX439U, SRX488U, SH804, SH840, SR2107, SR2115; YR3370, TSR1122, TSR102, TSR108, TSR116, TSR117, TSR125A, TSR127B, TSR144, TSR180, TSR187, YR47, YR3187, YR3224, YR3232, YR3270, YR3340, TE2173, TE2 , Reactive silicone compounds (specifically, there are addition reaction type, peroxide curable type, ultraviolet curable type, and TSR1500, TSR1510, TSR1511, TSR1515, TSR1520, YR3286, YR3340, PSA6574, manufactured by Toshiba Silicones as commercially available products. TPR6500, TPR6501, TPR6600, TPR6702, TPR6604, TP R6700, TPR6701, TPR6705, TPR6707, TPR6708, TPR6710, TPR6712, TPR6721, TPR6722, UV9300, UV9315, UV9425, UV9430, XS56-A2775, XS56-A2982, XS56-A3075, XS56-A3957, XS56S30X80 XS56-B1794, SL6100, SM3000, SM3030, SM3200, YSR3022, and the like.

  Examples of the fluorine compound include fluorine oil (Daikin Industries # 1, # 3, # 10, # 20, # 50, # 100, Unidyne TG-440, TG-452, TG-490, TG-560 as commercial products. TG-561, TG-590, TG-652, TG-670U, TG-991, TG-999, TG-3010, TG-3020, TG-3510; TF-100, MF-110, MF manufactured by Tochem Products -120, MF-130, MF-160, MF-160E; Asahi Glass Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145; FC-430, FC-431 made by Mitsui Fluorochemical, etc.), fluoro rubber (LS63U made by Toray Dow Corning Silicone as a commercial product) Fluorine-modified resin (Nippon Yushi Modiper F200, F220, F600, F2020, F3035; Dainippon Chemical Dialomer FF203, FF204; Asahi Glass Surflon S-381, S-383, S-393, SC- 101, SC-105, KH-40, SA-100; EF-351, EF-352, EF-801, EF-802, EF-601, TFE, TFEA, TFEMA, PDFOH manufactured by Tochem Products; THV manufactured by Sumitomo 3M -200P, etc.), fluorine sulfonic acid compounds (commercially available products EF-101, EF-102, EF-103, EF-104, EF-105, EF-112, EF-121, EF-122A, EF manufactured by Tochem Products) -122B, EF-122C, EF-123A, EF-123B, E -125M, EF-132, EF-135M, EF-305, FBSA, KFBS, LFBS, etc., fluorosulfonic acid, fluorinated acid compounds and salts (specifically, hydrofluoric acid, dilute hydrofluoric acid, borofluoric acid, borofluoride) Zinc, nickel borofluoride, tin borofluoride, lead borofluoride, copper borofluoride, silicic acid, potassium fluoride titanate, perfluorocaprylic acid, ammonium perfluorooctanoate, etc., inorganic fluoride (specifically fluoride) Aluminum, potassium silicofluoride, potassium fluoride zirconate, zinc fluoride tetrahydrate, calcium fluoride, lithium fluoride, barium fluoride, tin fluoride, potassium fluoride, acidic potassium fluoride, magnesium fluoride, fluoride Titanic acid, zirconic fluoride, ammonium hexafluorophosphate, potassium hexafluorophosphate Etc.).

  Examples of the wax include synthetic hydrocarbons, modified waxes, hydrogenated waxes, and natural waxes.

  Examples of the synthetic hydrocarbons include polyethylene wax (as commercially available products Polylon A, 393, H-481, manufactured by Chukyo Yushi; Sun wax E-310, E-330, E-250P, LEL-250, LEL- 800, LEL-400P, etc.), polypropylene wax (commercially available products are Sanyo Chemical Co., Ltd. Biscol 330-P, 550-P, 660-P), Fischer-Tropsch wax (commercially available products are FT100, FT-0070, etc. manufactured by Nippon Seiki), Acid amide compound or acid imide compound (specifically, stearamide, phthalic anhydride, etc., commercially available products such as Chukyo Yushi Cellosol 920, B-495, Hymicron G-270, G-110, Hydrin D-757) Etc.).

  Examples of the modified wax include amine-modified polypropylene (QN-7700 manufactured by Sanyo Chemical Co., Ltd. as a commercial product), acrylic acid-modified, fluorine-modified, olefin-modified wax, and urethane type wax (NPS-6010 manufactured by Nippon Seiki Co., Ltd. as a commercial product). -5090), alcohol type wax (NPS-9210, NPS-9215, OX-1949, XO-020T, etc., manufactured by Nippon Seiki) and the like.

  Examples of the hydrogenated wax include hardened castor oil (as a commercially available product, castor wax from Ito Oil Co., Ltd.), castor oil derivatives (dehydrated castor oil DCO, DCO Z-1, DCO Z-3, castor from Ito Oil as commercial products). Oil fatty acid CO-FA, ricinoleic acid, dehydrated castor oil fatty acid DCO-FA, dehydrated castor oil fatty acid epoxy ester D-4 ester, castor oil-based urethane acrylate CA-10, CA-20, CA-30, castor oil derivative MINERASOL S -74, S-80, S-203, S-42X, S-321, Special castor oil-based condensed fatty acid MINERASOL RC-2, RC-17, RC-55, RC-335, Special castor oil-based condensed fatty acid ester MINERASOL LB-601, LB-603, LB-604, LB-702, L B-703, # 11, L-164, etc.), stearic acid (12-hydroxystearic acid made by Ito Oil as a commercial product), lauric acid, myristic acid, palmitic acid, behenic acid, sebacic acid (as commercial products) Sebacic acid from Ito Oil), undecylenic acid (such as undecylenic acid from Ito Oil as a commercial product), heptylic acid (such as heptyl acid from Ito Oil as a commercial product), maleic acid, highly maleated oil (as a commercial product) HIMALIN DC-15, LN-10, 00-15, DF-20, SF-20, etc., manufactured by Ito Oil Co., Ltd., blown oil (commercially available, Celbonol # 10, # 30, # 60, R-40 manufactured by Ito Oil Co., Ltd.) , S-7, etc.), cyclopentadiene oils (commercially available products such as CP oil and CP oil-S made by Ito Oil) And the like.

  The natural wax is preferably at least one selected from vegetable wax, animal wax, mineral wax and petroleum wax.

Examples of the plant wax include carnauba wax (Nippon Seiki EMUSTAR-0413, Chukyo Yushi Cellosol 524, etc. as commercial products), castor oil (commercially available Ito Oil refined castor oil, etc.), rapeseed oil, large Examples include bean oil, wax, cotton wax, rice wax, sugarcane wax, candelilla wax, Japan wax, jojoba oil, and the like. Among these, in particular, it has an excellent offset resistance, adhesion resistance, paper permeability, glossiness, is resistant to cracking, and can provide an electrophotographic image-receiving sheet capable of forming a high-quality image. Is particularly preferably a carnauba wax having a temperature of 70 to 95 ° C.
Examples of the animal wax include lanolin, spermaceti, stew wax (whale oil), and wool wax.

  Examples of the mineral wax include, for example, montan wax, montan ester wax, ozokerite, ceresin, fatty acid ester (commercially available products are Sansizer DOA, AN-800, DINA, DIDA, DOZ, DOS, TOTM, TITM manufactured by Shin Nippon Rika). , E-PS, nE-PS, E-PO, E-4030, E-6000, E-2000H, E-9000H, TCP, C-1100, etc.). Among these, in particular, it has an excellent anti-offset property, anti-adhesion property, paper passing property, glossiness, is resistant to cracking, and can provide an electrophotographic image-receiving sheet capable of forming a high-quality image. Is particularly preferably a montan wax of carnauba wax having a temperature of 70 to 95 ° C.

  Examples of the petroleum wax include paraffin wax (paraffin wax 155, 150, 140, 135, 130, 125, 120, 115, HNP-3, HNP-5, HNP-9, HNP- 10, HNP-11, HNP-12, HNP-14G, SP-0160, SP-0145, SP-1040, SP-1035, SP-3040, SP-3035, NPS-8070, NPS-L-70, OX- 2151, OX-2251, EMUSTAR-0384, EMUSTAR-0136, Chukyo Oil & Fats Cellosol 686, 428, 651-A, A, H-803, B-460, E-172, 866, K-133, Hydrin D-337 E-139, 125 ° paraffin, 125 ° FD, 130 ° Fins, 135 ° paraffin, 135 ° H, 140 ° paraffin, 140 ° N, 145 ° paraffin, paraffin wax M, etc., microcrystalline wax (commercially available from Nihon Seiki Hi-Mic-2095, Hi-Mic-3090) , Hi-Mic-1080, Hi-Mic-1070, Hi-Mic-2065, Hi-Mic-1045, Hi-Mic-2045, EMUSTAR-0001, EMUSTAR-042X, Chukyo Oil & Fats Cellosol 967, M, Nisseki Mitsubishi Petroleum (manufactured by Nippon Seiki OX-1749, OX-0450, OX-0650B, OX-0153, OX-261BN, OX-0551, OX-0550, OX) -0750B, JP- 500, JP-056R, such as JP-011P) and the like.

The content in the toner image-receiving layer of the natural wax (surface) is preferably ^{0.1~4g / m 2, 0.2~2g / m} 2 is preferred.
When the content is less than 0.1 g / m ² , offset resistance and adhesion resistance may be particularly insufficient. On the other hand, when the content exceeds 4 g / m ² , the amount of wax is excessive and formed. The image quality of images may be inferior.
The melting point (° C.) of the natural wax is preferably 70 to 95 ° C., more preferably 75 to 90 ° C., particularly in terms of offset resistance and paper passing properties.

Examples of the matting agent include various known ones. Solid particles used as a matting agent can be classified into inorganic particles and organic particles.
Specific examples of the material for the inorganic matting agent include oxides (eg, silicon dioxide, titanium oxide, magnesium oxide, aluminum oxide), alkaline earth metal salts (eg, barium sulfate, calcium carbonate, magnesium sulfate), Examples thereof include silver halide (for example, silver chloride, silver bromide), glass, and the like.

  Examples of the inorganic matting agent include West German Patent 2529321, British Patent 760775, 1260772, U.S. Patent 1201905, 2192241, 3030562, 3030649, 3257206, 3322555, and 3353958. No. 3,370,951, No. 3,411,907, No. 3,437,484, No. 3523022, No. 3,615,554, No. 3,635,714, No. 3769020, No. 40212245, and No. 4029504.

Examples of the material for the organic matting agent include starch, cellulose ester (for example, cellulose acetate propionate), cellulose ether (for example, ethyl cellulose), and synthetic resin. The synthetic resin is preferably water-insoluble or poorly water-soluble.
Examples of the water-insoluble or poorly water-soluble synthetic resin include poly (meth) acrylic acid esters (for example, polyalkyl (meth) acrylate, polyalkoxyalkyl (meth) acrylate, polyglycidyl (meth) acrylate), poly (meth) acrylate. ) Acrylamide, polyvinyl ester (eg, polyvinyl acetate), polyacrylonitrile, polyolefin (eg, polyethylene), polystyrene, benzoguanamine resin, formaldehyde condensation polymer, epoxy resin, polyamide, polycarbonate, phenol resin, polyvinyl carbazole, polyvinylidene chloride, etc. Is mentioned.
You may use the copolymer which combined the monomer used for the above polymer.

In the case of the copolymer, a small amount of hydrophilic repeating units may be contained. Examples of the monomer that forms the hydrophilic repeating unit include acrylic acid, methacrylic acid, α, β-unsaturated dicarboxylic acid, hydroxyalkyl (meth) acrylate, sulfoalkyl (meth) acrylate, and styrenesulfonic acid. Can be mentioned.
Examples of the organic matting agent include British Patent No. 1055713, U.S. Pat. Nos. 1,939,213, 2221873, 2268661, 2322037, 2376005, 2391181, 2701245, 2992101, and 3079257. Nos. 3,262,782, 3,443,946, 3,516,832, 3,539,344, 3,591,379, 3,754,924, 3,767,448, JP-A-49-106821, JP-A-57-14835 Are described in the above.
Two or more kinds of solid particles may be used in combination. The average particle size of the solid particles is, for example, preferably 1 to 100 μm, and more preferably 4 to 30 μm. The amount of the solid particles is preferably ^{0.01~0.5g / m 2, 0.02~0.3g / m} 2 is more preferable.

  As the release agent added to the toner image-receiving layer, these derivatives, oxides, purified products, and mixtures can also be used. Moreover, these may have a reactive substituent.

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.
The release agent is particularly preferably a water-dispersed release agent from the viewpoint of compatibility when an aqueous thermoplastic resin is used as the thermoplastic resin of the toner image receiving layer.
The content of the release agent is preferably 0.1 to 10% by mass, more preferably 0.3 to 8.0% by mass, and further 0.5 to 5.0% by mass with respect to the total amount of the toner image-receiving layer. preferable.

-Plasticizer-
As the plasticizer, known plasticizers for resins can be used without particular limitation. The plasticizer has a function of adjusting the flow or softening of the toner image-receiving layer by heat and / 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.

Some of the plasticizers are described as high-boiling organic solvents and thermal solvents. For example, JP-A-59-83154, 59-178451, 59-178453, and 59-178454. 59-178455, 59-178457, 62-174754, 62-245253, 61-209444, 61-200538, 62-8145, 62-9348, 62-30247, 62-136646, 62-174754, 62-245253, 61-209444, 61-200538, 62-8145, 62-9348, 62- Esters such as those described in publications such as 30247, 62-136646, and JP-A-2-235694 (examples) For example, phthalic acid esters, phosphoric acid esters, fatty acid esters, abietic acid esters, adipic acid esters, sebacic acid esters, azelaic 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 And stearic acid esters), amides (for example, fatty acid amides, sulfoamides, etc.), ethers, alcohols, lactones, polyethyleneoxy compounds and the like.
The plasticizer can be used by mixing with a resin.

A relatively low molecular weight polymer can be used as the plasticizer. In this case, the molecular weight of the plasticizer is preferably lower than the molecular weight of the binder resin to be plasticized. The molecular weight of the plasticizer is preferably 15000 or less, and 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, Adeka Sizer PN-170, PN-1430 manufactured by Asahi Denka Kogyo; P. HALL products PARAPLEX-G-25, G-30, G-40; Rika Hercules products Ester gum 8L-JA, Ester R-95, Pentaline 4851, FK115, 4820, 830, Louisol 28-JA, Picolastic A75, Pico Examples include Tex LC and Crystallex 3085.

The plasticizer relieves stress and strain (physical strain such as elastic force and viscosity, strain due to mass balance of molecules, binder main chain, pendant, etc.) generated when toner particles are embedded in the toner image receiving layer. Can be used arbitrarily to
The plasticizer may be in a micro-dispersed state in the toner image-receiving layer, may be in a phase-separated microscopically in a sea-island shape, or may be in a sufficiently mixed and dissolved state 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-
Examples of the colorant include fluorescent whitening agents, white pigments, colored pigments, and dyes.
The fluorescent whitening agent is a compound that absorbs in the near ultraviolet region and emits fluorescence at 400 to 500 nm, and various known fluorescent whitening agents can be used without particular limitation. Examples of the optical brightener include K.I. Preferable examples include the compounds described in “The Chemistry of Synthetic Dies” edited by Veen Rataraman, Vol. Specific examples include stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, pyrazoline compounds, carbostyryl compounds, and the like. Examples thereof include white fur fur PSN, PHR, HCS, PCS, B manufactured by Sumitomo Chemical; UVITEX-OB manufactured by Ciba-Geigy.

As the white pigment, an inorganic pigment (for example, titanium oxide, calcium carbonate, etc.) in the filler section described later can be used.
Examples of the colored pigment include various pigments and azo pigments described in JP-A-63-44653 (for example, azo lake; carmine 6B, red 2B, insoluble azo; monoazo yellow, disazo yellow, pyrazolo orange, vulcan orange, Condensed azo series; chromophyl yellow, chromophthal red), polycyclic pigments (eg, phthalocyanine series; copper phthalocyanine blue, copper phthalocyanine green, dioxazine series; dioxazine violet, isoindolinone series; isoindolinone yellow, slen series Perylene, perinone, flavantron, thioindigo; lake pigments (eg, malachite green, rhodamine B, rhodamine G, Victoria blue B); inorganic pigments (eg, oxide, titanium dioxide, bengara, sulfate; precipitated barium sulfate) And carbonates; precipitated calcium carbonate, succinate; hydrous succinate, anhydrous succinate, metal powder; aluminum powder, bronze powder, zinc powder, carbon black, chrome lead, bitumen, etc.) .
These may be used alone or in combination of two or more. Among these, titanium oxide is particularly preferable as the pigment.

Various known dyes can be used as the dye.
Examples of the oil-soluble dye include anthraquinone compounds and azo compounds.
Examples of the water-insoluble dye 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 dyes such as Vat Blue 35; 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 dyes such as Disperse Blue 58; 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, and the like.
A colored coupler used in silver salt photography can also be preferably used.

Of the colorant, the content in the toner image-receiving layer (surface) 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 , the light transmittance in the toner image-receiving layer is increased. On the other hand, when the content of the colorant exceeds 8 g / m ² , cracking and adhesion resistance are increased. The handleability may be poor.

-Filler-
As said filler, an organic filler or an 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 Basics and Applications" (Taiseisha), "Filler Handbook" (Taiseisha), etc. Can do.
Moreover, various inorganic fillers (or pigments) can be used as the filler. Examples of the inorganic pigment include silica, alumina, titanium dioxide, zinc oxide, zirconium oxide, mica-like iron oxide, white lead, lead oxide, cobalt oxide, strontium chromate, molybdenum pigment, smectite, magnesium oxide, calcium oxide, Examples include calcium carbonate and mullite. As the filler, silica and alumina are particularly preferable. These fillers 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 silica, colloidal silica is preferable. The average particle diameter of silica is preferably 200 to 5000 nm.
The silica is preferably porous. The average pore diameter of the porous silica is preferably 4 to 120 nm, and more preferably 4 to 90 nm. The average pore volume per mass of the porous silica is preferably 0.5 to 3 ml / g.

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. Alumina hydrate is preferred over 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 average particle diameter of the alumina is preferably 4 to 300 nm, and more preferably 4 to 200 nm. The alumina is preferably porous. The average pore diameter of the porous alumina is preferably 50 to 500 nm. The average pore volume per mass of the porous alumina is preferably about 0.3 to 3 ml / g.

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 based on 100 parts by mass of the dry mass of the binder of the toner image-receiving layer.

-Crosslinking agent-
The cross-linking agent can be blended in order to adjust the storage stability of the toner image-receiving layer, the thermoplasticity, and the like. As such a crosslinking agent, a compound having two or more known reactive groups in the molecule as an reactive group such as epoxy group, isocyanate group, aldehyde group, active halogen group, active methylene group, acetylene group and the like is used.

As the cross-linking agent, a compound having two or more groups capable of forming a bond by hydrogen bond, ionic bond, coordination bond or the like can be used.
As the crosslinking agent, known compounds can be used as coupling agents for resins, curing agents, polymerization agents, polymerization accelerators, coagulants, film-forming agents, film-forming aids, and the like. Examples of coupling agents include, for example, chlorosilanes, vinyl silanes, epoxy silanes, aminosilanes, alkoxyaluminum chelates, titanate coupling agents, etc. "Handbook Rubber / Plastic Compounding Chemicals" (Rubber Digest Co., Ltd.) Ed) and the like can be used.

-Charge control agent-
The toner image-receiving layer preferably contains a charge control agent in order to adjust toner transfer, adhesion, etc., and to prevent charge adhesion of the toner image-receiving layer.
As the charge control agent, conventionally known various charge control agents can be used. Such charge control agents include, for example, cationic surfactants, anionic surfactants, amphoteric surfactants, surfactants such as nonionic surfactants, polymer electrolytes, conductive metal oxides, etc. Things can be used. For example, 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, nonions such as fatty acid esters and polyethylene oxide Examples thereof include, but are not limited to, antistatic agents.

When the toner has a negative charge, for example, a cation or nonion is preferable as the charge control agent to be 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 conductive metal oxides may be used alone or in combination with these composite oxides. The metal oxide may further contain a different element, for example, Al, In, etc. for ZnO, Nb, Ta, etc. for TiO ₂ , Sb, Nb for SnO ₂ . Further, a halogen element or the like can be contained (doping).

-Other additives-
The material that can be used for the toner image-receiving layer may 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.

  Examples of the antioxidant include a chroman compound, a coumaran compound, a phenol compound (eg, hindered phenol), a hydroquinone derivative, a hindered amine derivative, and a spiroindane compound. The antioxidant is described in JP-A No. 61-159644.

  Examples of the antiaging agent include those described in “Handbook Rubber / Plastic Compounding Chemicals Revised 2nd Edition” (1993, Rubber Digest Co.) p76-121.

  Examples of the ultraviolet absorber include benzotriazole compounds (described in U.S. Pat. No. 3,533,794), 4-thiazolidone compounds (described in U.S. Pat. No. 3,352,681), benzophenone compounds (described in JP-A-46-2784), and Examples thereof include ultraviolet absorbing polymers (described in JP-A-62-260152).

Examples of the metal complex include U.S. Pat. Nos. 4,241,155, 4,425,018 and 4,254,195, JP-A-61-88256, JP-A-62-174741, JP-A-63-199248, JP-A-1-75568. Nos. 1 and 74272 are appropriate.
Further, ultraviolet absorbers and light stabilizers described in "Handbook Rubber / Plastic Compounding Chemicals Revised 2nd Edition" (1993, Rubber Digest Co., Ltd.) p122 to 137 are also preferably used.

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

Type of additive RD17643 RD18716 RD307105
1. Brightener 24 pages 648 right column 868 pages 2. Stabilizer Pages 24-25 Page 649 Right column 868-870 Light Absorber Page 25-26 Page 649 Right Column 873 (Ultraviolet Absorber)
4). Dye image stabilizer page 25 page 650 right column page 872 5. Hardener 26 pages 651 left column 874-875 6. Binder page 26 page 651 left column pages 873-874 Plasticizer, lubricant page 27 page 650 right column page 876 8. Coating aid 26-27 pages 650, right column 875-876 (surfactant)
9. Antistatic agent page 27 page 650 right column pages 876-877
Ten. Matting agent 878-879 pages

  The thickness of the toner image receiving layer is, for example, preferably 1 to 50 μm, and more preferably 5 to 15 μm.

[Physical properties of toner image-receiving layer]
The toner image receiving layer preferably has high whiteness. The whiteness is preferably 85% or more as measured by the method defined in JIS P 8123. Further, in the wavelength range 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, it is more preferable that the spectral reflectance is 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 within 5%.
Further, 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. As the glossiness, the 45 ° glossiness is preferably 60 or more, more preferably 75 or more, and still 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.
In addition, the said glossiness can be measured based on JISZ8741.

The toner image receiving layer preferably has high smoothness. 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.
The arithmetic average roughness can be measured based on JIS B 0601, B 0651, and B 0652.

The toner image-receiving layer preferably has physical properties of one of the following items, more preferably a plurality of items, and most preferably all physical properties.
(1) The toner image-receiving layer has a Tg (glass transition temperature) of 30 ° C. or higher and a toner Tg + 20 ° C. or lower.
(2) T1 / 2 (1/2 method softening point) of the toner image-receiving layer is 60 to 200 ° C., preferably 80 to 170 ° C. Here, the 1/2 method softening point is a preheating time at an initial set temperature (for example, 50 ° C.), for example, 300 seconds while applying a predetermined extrusion load under a specific condition using a specific apparatus. Later, evaluation is made at a temperature that is one-half of the difference between the piston stroke at the start and end of outflow at each temperature when the temperature is increased at a predetermined constant temperature increase rate.
(3) Tfb (outflow start temperature) of the toner image-receiving layer is 40 to 200 ° C., preferably, Tfb of the toner image-receiving layer is Tfb + 50 ° C. or less of the toner.
(4) The temperature at which the viscosity of the toner image-receiving layer becomes 1 × 10 ⁵ cp is 40 ° C. or higher and lower than that of the toner.
(5) 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. is there.
(6) The loss tangent (G ″ / G ′), which is the ratio between the loss elastic modulus (G ″) at the fixing temperature of the toner image-receiving layer and the storage elastic modulus (G ′), is 0.01 to 10.
(7) The storage elastic modulus (G ′) at the fixing temperature of the toner image-receiving layer is −50 to +2500 with respect to the loss elastic modulus (G ″) at the fixing temperature of the toner.
(8) The inclination angle of the molten toner on the toner image-receiving layer is 50 degrees or less, particularly 40 degrees or less.
The toner image-receiving layer preferably satisfies the physical properties disclosed in Japanese Patent No. 2788358, Japanese Patent Application Laid-Open Nos. 7-248637, 8-305067, and 10-239889.

  The physical property (1) can be measured by a differential scanning calorimeter (DSC). The physical properties (2) to (3) can be measured using, for example, a flow tester CFT-500 or 500D manufactured by Shimadzu Corporation. The physical properties (5) to (7) can be measured using a rotational rheometer (for example, a dynamic analyzer RADII manufactured by Rheometric). The physical property (8) can be measured by a method disclosed in JP-A-8-334916 using a contact angle measuring device manufactured by Kyowa Interface Science Co., Ltd.

The toner image-receiving layer preferably has a surface electrical resistance in the range of 1 × 10 ⁶ to 1 × 10 ¹⁵ Ω / cm ² (under conditions of 25 ° C. and 65% RH).
When the surface resistance is less than 1 × 10 ⁶ Ω / cm ² , the toner amount when the toner is transferred to the toner image-receiving layer is not sufficient, and the density of the obtained toner image tends to be low. If the surface electrical resistance exceeds 1 × 10 ¹⁵ Ω / cm ² , an excessive charge is generated during transfer, the toner is not sufficiently transferred, the image density is low, and the electrophotographic image receiving sheet is being handled. Dust easily adheres due to static electricity, and misfeed, double feed, discharge mark, toner transfer missing, etc. may occur during copying.

The surface electrical resistance of the surface opposite to the toner image-receiving layer with respect to the support is preferably 5 × 10 ^{8 to} 3.2 × 10 ¹⁰ Ω / cm ² and 1 × 10 ⁹ to 1 × 10 ^10. More preferable is Ω / cm ² .
The measurement of the surface electrical resistance is based on JIS K 6911, 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, an 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 include a surface protective layer, a back layer, an adhesion improving layer, an intermediate layer, an undercoat layer, a cushion layer, a charge control (preventing) layer, a reflective layer, a tint adjusting layer, a storage stability improving layer, and an adhesive. Examples include a prevention 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 used for the purpose of protecting the surface of the electrophotographic image-receiving sheet, improving storage stability, improving handleability, imparting writing properties, improving instrument passage properties, imparting anti-offset properties, and the like. It can be provided on the surface of the image receiving layer. 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 contain other additives such as a matting agent together with the release agent. In addition, as said mat agent, various well-known things are mentioned.
The outermost surface layer in the electrophotographic image-receiving sheet (for example, the 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 image-receiving sheet, 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, and improving device passability. It is preferred that
Although there is no restriction | limiting in particular as a color of the said back layer, When the said electrophotographic image receiving sheet 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.

-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 image receiving sheet. 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 image-receiving sheet is preferably further provided with a cushion layer or the like between the adhesion improving layer and the toner image-receiving layer in order to improve 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. In the case of an electrophotographic image receiving sheet 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.

  The thickness of the electrophotographic image receiving sheet is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 50 to 350 μm, and more preferably 100 to 280 μm.

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

-Toner binder resin-
Examples of the binder resin include styrenes such as styrene and parachlorostyrene; vinyl esters such as vinyl naphthalene, vinyl chloride, vinyl bromide, vinyl fluoride, vinyl acetate, vinyl propionate, vinyl benzoate, and vinyl butyrate; Methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, methacryl Methylene aliphatic carboxylic acid esters such as ethyl acetate and butyl methacrylate; Vinyl nitriles such as acrylonitrile, methacrylonitrile, and acrylamide; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether Tells; N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone; single weight of vinyl monomers such as vinyl carboxylic acids such as methacrylic acid, acrylic acid and cinnamic acid Copolymers, 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 for the toner image receiving layer.

-Toner Colorant-
As the colorant, those usually used in toners can be used without limitation. For example, carbon black, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, pyrazolone. Orange, Vulcan Orange, Watch Young Red, Permanent Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Risor Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Examples include various pigments such as oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, and malachite green oxalelate. 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.
The content of the colorant is preferably in the range of 2 to 8% by mass. If the content of the colorant is 2% by mass or more, the coloring power is not weakened. On the other hand, if it is 8% by mass or less, the transparency is not impaired, which is preferable.

-Toner release agent-
As the mold release agent, all known waxes can be used in principle, but polar waxes containing nitrogen such as relatively low molecular weight high crystalline polyethylene wax, Fischer-Tropsch wax, amide wax, urethane compound, etc. Etc. are particularly effective. The polyethylene wax having a molecular weight of 1000 or less is particularly effective, and a range of 300 to 1000 is more preferable.

  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. The preferred range of molecular weight is 300-1000. The raw materials are a combination of diisocyanate compounds and monoalcohols, a combination of monoisocyanic acid and monoalcohol, a combination of dialcohols and monoisocyanic acid, a combination 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 amount. It is important to ensure that

Specific examples of the raw material compound include monoisocyanate compounds such as dodecyl isocyanate, phenyl isocyanate and derivatives thereof, naphthyl isocyanate, hexyl isocyanate, benzyl isocyanate, butyl isocyanate, and allyl isocyanate. It is done.
Examples of the diisocyanate compound include tolylene diisocyanate, 4,4′diphenylmethane diisocyanate, toluene diisocyanate, 1,3-phenylene diisocyanate, hexamethylene diisocyanate, 4-methyl-m-phenylene diisocyanate, and isophorone diisocyanate. Can be mentioned.
As the monoalcohol, it is possible to use very common alcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol, and heptanol.
Among the raw material compounds, as the dialcohols, a number of glycols such as ethylene glycol, diethylene glycol, triethylene glycol, trimethylene glycol; as the trialcohols, trimethylolpropane, triethylolpropane, trimethanolethane, etc. can be used. However, it is not necessarily limited to this range.

  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. Also, when used in the emulsion polymerization aggregation melting toner described above, it is dispersed in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid or a polymer base, and heated to a melting point or higher to produce a homogenizer or pressure discharge. A fine dispersion is obtained 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.

-Toner and other components-
The toner may contain other components such as an internal additive, a charge control agent, and inorganic fine particles. As the internal additive, a magnetic material such as a metal such as ferrite, magnetite, reduced iron, cobalt, nickel, manganese, an alloy, or a compound containing these metals can be used.

  As the charge control agent, 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 may be used. it can. 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.

  Examples of the inorganic fine particles include silica, alumina, titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, and the like. Usually, all external additives on the toner surface are used. It is preferable to use by dispersing with a molecular 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, a dyno mill or the like can be used.

An external additive may be further added to the toner as necessary. Examples of the external additive include inorganic powder 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 · 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, resin powder, such as fatty acid or its derivative (s), powders, such as these metal salts, a fluorine resin, a polyethylene resin, an acrylic resin, can be used. The average particle diameter of these powders is, for example, 0.01-5 μm, preferably 0.1-2 μm.

  The method for producing the toner is not particularly limited, and (i) a step of forming aggregated particles in a dispersion obtained by dispersing resin particles to prepare an aggregated particle dispersion, (ii) in the aggregated particle dispersion. A step of adding and mixing a fine particle dispersion in which fine particles are dispersed to adhere the fine particles to the aggregated particles to form adhered particles; and (iii) heating and fusing the adhered particles to form toner particles. Those obtained by a method for producing a toner including the steps are preferable.

-Toner physical properties-
The volume average particle diameter of the toner is preferably 0.5 μm or more and 10 μm or less.
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.
The toner preferably satisfies the toner volume average particle size range 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.
Further, the toner preferably 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 has an effect on image quality, particularly graininess and resolution, and it is difficult to cause omission and blur due to transfer, and handling properties are adversely affected even if the average particle size is not small. It becomes difficult.

  The storage elastic modulus G ′ (measured at an angular frequency of 10 rad / sec) at 150 ° C. of the toner itself is 10 to 200 Pa from the viewpoint of improving the image quality and preventing the offset property in the fixing process. .

(Image forming method)
The image forming method of the present invention is a belt fixing type comprising a toner image forming step of forming a toner image on the electrophotographic image receiving sheet of the present invention, a heating and pressing member, a belt member, and a cooling device. And a fixing and smoothing step of heating and pressing using a smoothing processor, cooling and peeling, and further having other means as necessary.
It is preferable that the toner image forming step includes a toner image fixing step in which the toner image formed on the electrophotographic image receiving sheet is fixed by a heat roller.

-Toner image forming process-
The toner image forming step is not particularly limited as long as it can form a toner image on an electrophotographic image-receiving sheet, and can be appropriately selected according to the purpose. For example, a normal electrophotographic method can be used. The method used, for example, a direct transfer method in which a toner image formed on a developing roller is transferred to an electrophotographic image receiving sheet, or an intermediate transfer belt that is transferred to an electrophotographic image receiving sheet after primary transfer to an intermediate transfer belt or the like There is a method. From the viewpoint of environmental stability and high image quality, an intermediate transfer belt system is preferably used.

-Fixing smoothing process-
The fixing and smoothing step is a step of heating and pressurizing the toner image using a belt fixing type smoothing processor having a heating and pressing member, a belt member, and a cooling device, cooling and peeling the toner image.
The belt fixing type smoothing processor includes a heating / pressurizing member, a belt member, and a cooling device, and further includes a cooling separation portion and other members as necessary.

The heating and pressing member is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a pair of heating rollers and a combination of a heating roller and a pressing roller.
There is no restriction | limiting in particular as said cooling device, Although it can select suitably according to the objective, For example, a cooling device, a heat sink, etc. which can blow cold air and can adjust cooling temperature etc. are used.
There is no restriction | limiting in particular as said cooling peeling part, According to the objective, it can select suitably, The tension roll vicinity position which peels from a belt with the rigidity (strength of waist) of the electrophotographic image receiving sheet itself is meant.

It is preferable to apply pressure when contacting the heating and pressing member of the belt-type smoothing processor. There is no restriction | limiting in particular as this pressurization method, Although it can select suitably according to the objective, It is preferable to employ | adopt a nip pressure. The nip pressure is preferably 1 to 100 kgf / cm ^{2 and} more preferably 5 to 30 kgf / cm ² from the viewpoint of forming an image having excellent water resistance and surface smoothness and good gloss. Further, the heating in the heating and pressing member is a temperature equal to or higher than the softening point of the thermoplastic resin in the toner image receiving layer, and varies depending on the thermoplastic resin used, but is usually preferably 80 ° C. or higher and 180 ° C. or lower. The cooling temperature in the cooling device is preferably 80 ° C. or less, more preferably 20 to 80 ° C., at which the thermoplastic resin layer in the toner image receiving layer is sufficiently solidified.

The belt member includes a heat resistant support film and a release layer formed on the support film.
The support film is not particularly limited as long as it has heat resistance, and can be appropriately selected according to the purpose. For example, polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), Examples include polyetheretherketone (PEEK), polyethersulfone (PES), polyetherimide (PEI), polyparabanic acid (PPA), and the like.

  The release layer is preferably at least one selected from silicone rubber, fluorine rubber, fluorocarbon siloxane rubber, silicone resin and fluorine resin. Among these, a mode in which a fluorocarbon siloxane rubber layer is provided on the surface of the belt member and a mode in which a silicone rubber layer is provided on the surface of the belt member and a fluorocarbon siloxane rubber layer is provided on the surface of the silicone rubber layer are preferable.

The fluorocarbon siloxane rubber preferably has at least one of a perfluoroalkyl ether group and a perfluoroalkyl group in the main chain.
As said fluorocarbon siloxane rubber, the hardened | cured material of the fluorocarbon siloxane rubber composition containing the following (A)-(D) component is suitable.
(A) a fluorocarbon polymer having a fluorocarbon siloxane represented by the following general formula (1) as a main component and having an aliphatic unsaturated group; (B) containing two or more ≡SiH groups in one molecule; At least one of organopolysiloxane and fluorocarbonsiloxane, wherein the content of ≡SiH group is 1 to 4 times the molar amount of the aliphatic unsaturated group in the product, (C) a filler, and (D) effective Amount of catalyst.

  The (A) component fluorocarbon polymer is mainly composed of a fluorocarbon siloxane having a repeating unit represented by the following general formula (1) and has an aliphatic unsaturated group.

In the general formula (1), R ¹⁰ is an unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms or alkenyl having 2 to 3 carbon atoms. And a methyl group is particularly preferable.
a and e each represents an integer of 0 or 1; b and d each represent an integer of 1 to 4. c represents an integer of 0 to 8. Further, x is preferably 1 or more, and more preferably 10-30.

As said (A) component, what is shown by following General formula (2) can be mentioned.

  In the component (B), examples of the organopolysiloxane having an ≡SiH group include organohydrogenpolysiloxanes having at least two hydrogen atoms bonded to silicon atoms in the molecule.

  In the fluorocarbon siloxane rubber composition, when the fluorocarbon polymer of the component (A) has an aliphatic unsaturated group, the above-described organohydrogenpolysiloxane is preferably used as the curing agent. . That is, a cured product is formed by an addition reaction that occurs between an aliphatic unsaturated group in the fluorocarbon siloxane and a hydrogen atom bonded to a silicon atom in the organohydrogenpolysiloxane.

  As the organohydrogenpolysiloxane, various organohydrogenpolysiloxanes used in addition-curable silicone rubber compositions can be used.

  In general, the number of ≡SiH groups in the organohydrogenpolysiloxane is preferably at least one with respect to one aliphatic unsaturated hydrocarbon group in the fluorocarbon siloxane as the component (A). It is preferable to mix | blend in the ratio which becomes an individual.

In addition, the fluorocarbon having a ≡SiH group includes the unit of the above general formula (1) or the above general formula (1), wherein R ¹⁰ is a dialkylhydrogensiloxy group and the terminal is a dialkylhydrogensiloxy group or a silyl group. What is SiH groups, such as group, is preferable, and what is shown by following General formula (3) can be mentioned.

  As the filler of the component (C), various fillers used in general silicone rubber compositions can be used. Examples of the filler include fumed silica, precipitated silica, carbon powder, titanium dioxide, aluminum oxide, quartz powder, reinforcing filler such as talc, sericite, bentonite, asbestos, glass fiber, organic fiber, and the like. Examples thereof include fibrous fillers.

  As the catalyst of the component (D), chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid and olefin, platinum black or palladium, which are known as addition reaction catalysts, alumina, silica, carbon, etc. And a compound of group VIII of the periodic table such as a complex of rhodium and olefin, chlorotris (triphenylphosphine) rhodium (Wilkinson catalyst), rhodium (III) acetylacetonate or the like. It is done. These complexes are preferably used by dissolving in a solvent such as an alcohol compound, an ether compound, or a hydrocarbon compound.

  There is no restriction | limiting in particular in the said fluorocarbon siloxane rubber composition, Although it can select suitably according to the objective, Various compounding agents can be added. For example, diphenylsilane diol, low-polymerization degree molecular chain terminal hydroxyl-blocked dimethylpolysiloxane, dispersant such as hexamethyldisilazane, heat resistance improver such as ferrous oxide, ferric oxide, cerium oxide, iron octylate Further, colorants such as pigments can be blended as necessary.

  The belt member is obtained by coating the surface of the heat-resistant support film with the fluorocarbon siloxane rubber composition and heat-curing, but if necessary, m-xylene hexafluoride, benzotrifluoride, etc. It can be applied by a general coating method such as spray coating, dip coating and knife coating. Moreover, the temperature and time of heat-curing can be selected suitably, and it selects according to the kind of a support body film, a manufacturing method, etc. in the range of temperature 100-500 degreeC and 5 second-5 hours.

  The thickness of the release layer formed on the surface of the heat-resistant support film is not particularly limited, but is 1 to 200 μm in order to obtain good image fixability by preventing toner releasability or toner component offset. Is preferable, and 5-150 micrometers is more preferable.

Hereinafter, a specific description will be given based on FIG. 1 showing an example of an image forming apparatus having a typical fixing belt.
First, the toner 12 is transferred to the electrophotographic image receiving sheet 1 by an image forming apparatus (not shown). The electrophotographic image-receiving sheet 1 to which the toner 12 is adhered is conveyed to point A by a transport facility (not shown), passes between the heating roller 14 and the pressure roller 15, and is a toner image-receiving layer of the electrophotographic image-receiving sheet 1. Alternatively, the toner 12 is heated and pressed at a temperature (fixing temperature) and pressure at which the toner 12 is sufficiently softened.

Here, the fixing temperature means the temperature of the surface of the toner image receiving layer measured at the position of the heating roller 14, the pressure roller 15, and the nip portion at point A, and is preferably 80 to 190 ° C., for example, 100 to 170 ° C. Is more preferable. The pressure means the pressure on the surface of the toner image receiving layer measured at the heating roller 14, the pressure roller 15, and the nip portion, and is, for example, 1 to 10 kgf / cm ² , more preferably ² to 7 kgf / cm ² . .
A release agent (not shown) discretely present in the toner image-receiving layer while the electrophotographic image-receiving sheet 1 is heated and pressurized in this way and is subsequently conveyed to the cooling device 16 by the fixing belt 13. Is sufficiently heated and melted, and moves to the surface of the toner image-receiving layer. The released release agent forms a release agent layer (film) on the surface of the toner image-receiving layer. Thereafter, the electrophotographic image-receiving sheet 1 is conveyed to the cooling device 16 by the fixing belt 13, and is, for example, below the softening point of the binder resin used for the polymer of the toner image-receiving layer and / or the toner or at the glass transition point + 10 ° C. or below. The temperature is preferably cooled to 20 to 80 ° C, more preferably to room temperature (25 ° C). As a result, the release agent layer (film) formed on the surface of the toner image-receiving layer is cooled and solidified to form a release agent layer.
The cooled electrophotographic image-receiving sheet 1 is further conveyed to point B by the fixing belt 13, and the fixing belt 13 moves on the tension roller 17. Accordingly, the electrophotographic image receiving sheet 1 and the fixing belt 13 are peeled off at the point B. In addition, it is preferable to set the diameter of the tension roll to be small so that the electrophotographic image-receiving sheet is peeled off from the belt by its own rigidity (waist strength).

The belt fixing type smoothing machine as shown in FIG. 3 is, for example, a belt-like fixing unit of the electrophotographic apparatus shown in FIG. 2 (for example, a full color laser printer (DCC-500) manufactured by Fuji Xerox Co., Ltd.). Can be used as modified.
In FIG. 2, 200 is an image forming apparatus, 37 is a photosensitive drum, 19 is a developing device, 31 is an intermediate transfer belt, 18 is an electrophotographic image receiving sheet, and 25 is a fixing belt portion (belt fixing device). , Respectively.
FIG. 3 shows a fixing belt portion (belt fixing device) 25 disposed inside the image forming apparatus 200 of FIG.
As shown in FIG. 3, the belt fixing device 25 includes a heating roll 71, an endless belt 73 rotatably supported by a peeling roll 74 including the heating roll 71, and a tension roll 75, and the heating roll 71. And a pressure roll 72 that is in pressure contact with the endless belt 73.
A cooling heat sink 77 for forcibly cooling the endless belt 73 is disposed between the heating roll 71 and the peeling roll 74 on the inner surface side of the endless belt 73. 77 constitutes a cooling / sheet conveying section for cooling the electrophotographic image-receiving sheet and conveying the sheet.

  In the belt fixing device 25, as shown in FIG. 3, an electrophotographic transfer sheet having a color toner image transferred and fixed on its surface is pressed against the heating roll 71 and the heating roll 71 via an endless belt 73. The color toner image is introduced into the pressure contact portion (nip portion) with the pressure roll 72 to be positioned so as to be positioned on the heating roll 71 side, and passes through the pressure contact portion between the heating roll 71 and the pressure roll 72. The color toner image is heated and melted and fixed on the electrophotographic image receiving sheet.

  Thereafter, in the press-contact portion between the heating roll 71 and the pressure roll 72, for example, the toner is heated to a temperature of about 120 to 130 ° C. and melted to fix the color toner image to the image receiving layer. The photographic image-receiving sheet is conveyed together with the endless belt 73 while the image-receiving layer on the surface thereof is in close contact with the surface of the endless belt 73. In the meantime, the endless belt 73 is forcibly cooled by a cooling heat sink 77, and after the color toner image and the image receiving layer are cooled and solidified, the peeling roller 74 uses the waist (rigidity) of the electrophotographic image receiving sheet itself. It is peeled off.

  The surface of the endless belt 73 after the peeling process is completed is prepared for the next fixing process by removing residual toner and the like by a cleaner (not shown).

  According to the image forming method of the present invention, even when an oilless machine without fixing oil is used, the electrophotographic image receiving sheet and the toner can be prevented from being peeled off, or the electrophotographic image receiving sheet and the toner component can be prevented from being offset. In addition, it is possible to realize a high-quality image similar to a silver salt photographic print with excellent moisture change cracking, adhesion resistance and cracking, and glossiness.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example 1)
-Preparation of support-
Hardwood bleached kraft pulp (LBKP) was beaten with a disc refiner to 300 ml (Canadian standard freeness, CSF) and adjusted to a fiber length of 0.58 mm. Additives were added to the pulp stock at the following ratio based on the mass of the pulp.
Type of additive Amount (%)
Cationic starch 1.2
Alkyl ketene dimer (AKD) 0.5
Anionic polyacrylamide 0.3
Epoxidized fatty acid amide (EFA) 0.2
Polyamide polyamine epichlorohydrin 0.3
Note) AKD means alkyl ketene dimer (the alkyl part is derived from a fatty acid mainly composed of behenic acid). EFA means epoxidized fatty acid amide (the fatty acid part is derived from a fatty acid mainly composed of behenic acid).

From the obtained pulp paper stock, a base paper having a basis weight of 150 g / m ² was prepared by a long net paper machine. Polyvinyl alcohol (PVA) 1.0 g / m ² and CaCl ₂ 0.8 g / m ² were adhered by a size press machine in the middle of the drying zone of the long paper machine.
At the end of the paper making process, the density was adjusted to 1.01 g / cm ³ using a soft calender. The obtained base paper was passed so that the metal roll was in contact with the side on which the toner image receiving layer was provided. The surface temperature of the metal roll was 140 ° C. The whiteness of the obtained base paper was 91%, the Oken type smoothness was 235 seconds, and the Steecht sizing degree was 119 seconds.

  After processing the obtained base paper by corona discharge with an output of 17 kW, using a cooling roll with a surface mat roughness of 10 μm on the back surface, a polyethylene resin having the composition shown in Table 1 below was melt-discharged film temperature 320 ° C., line speed 250 m A single layer extrusion lamination was performed at a rate of / min to provide a backside polyethylene resin layer having a thickness of 22 μm.

Next, using a cooling roll having a surface mat roughness of 0.7 μm on the surface of the base paper on which the toner image receiving layer is to be coated, the same LDPE and TiO ₂ as shown in Table 1 were made into a master batch as shown in Table 2. A surface polyethylene resin layer having a thickness of 29 μm was obtained by mixing a pellet obtained by mixing the pellets and the master batch containing 5% by mass of ultramarine as shown in Table 3 with a single layer extrusion lamination at a line speed of 250 m / min. Was provided. Thereafter, a corona discharge treatment of 18 kW on the front surface and 12 kW on the back surface was performed, and then a gelatin subbing layer was provided on the surface to prepare a support.

On the surface of the obtained support, a self-dispersing polyester resin aqueous dispersion (manufactured by Unitika, KZA-7049), carnauba wax aqueous dispersion (manufactured by Chukyo Yushi Co., Cellosol 524), titanium dioxide PVA-205 ( Kuraray Co., Ltd.) dispersion, polyethylene oxide having a weight average molecular weight (Mw) of about 100,000, and an anionic surfactant (manufactured by Nippon Oil & Fats, Rapisol A-90), and finally the coating amount of the toner image receiving layer shown in Table 4 An electrophotographic image-receiving sheet of Example 1 was prepared by providing a toner image-receiving layer with a bar coater so as to have a composition. The coating solution had a viscosity of 70 mPa · s, a surface tension of 30 mN / m, and a pH of 7.8.
The obtained electrophotographic image-receiving sheet of Example 1 had a mass of 211 g / m ² , a thickness of 198 μm, a whiteness of 88, and an opacity of 95.

(Examples 2 to 4 and Comparative Examples 1 to 4)
In Example 1, Examples 2 to 4 and Comparative Examples 1 to 4 were performed in the same manner as Example 1 except that the toner image receiving layer was provided by a bar coater so as to have the coating amount composition of the toner image receiving layer shown in Table 5. No. 4 electrophotographic image-receiving sheet was prepared.

<Evaluation of physical properties of electrophotographic image-receiving sheet>
Each electrophotographic image-receiving sheet obtained was evaluated for its bump water absorption, glossiness, and blister by the following methods. The results are shown in Table 6.

-Cobb water absorption-
It was measured by the Cobb sizing method water absorption test defined in JIS P 8140. Specifically, the water absorption was measured when pure water was brought into contact with the surface of the toner image-receiving layer in each electrophotographic image-receiving sheet for 300 seconds.

-Glossiness-
The following processing A and processing B were performed on each electrophotographic image-receiving sheet.
<Process A>
For each electrophotographic image-receiving sheet, the secondary transfer voltage was adjusted to be appropriate under the two conditions of cardboard using DC-400 manufactured by Fuji Xerox Co., Ltd. under the environmental conditions of 23 ° C. and 50% RH. A gray image of 6 levels from white to black was output.
<Process B>
For each electrophotographic image-receiving sheet, 6 levels of gray image from white to black using DC-400 manufactured by Fuji Xerox Co., Ltd. under the environmental conditions of 23 ° C., 50% RH and 23 ° C., 85% RH. Was transferred onto each electrophotographic image-receiving sheet, taken out from the apparatus in an unfixed state, and the unfixed print was glossed by a belt fixing post-processing apparatus shown in FIG. The temperature of the heating and pressing roller was set to 135 ° C., and the cooling peeling temperature was set to 70 ° C.

  In FIG. 1, as the fixing belt, DY39-115 (made by Toray Dow Corning Silicone Co., Ltd.), which is a silicone rubber primer, is applied on a polyimide base layer, then air-dried for 30 minutes, and then a silicone rubber precursor. A coating film is formed by dip coating with 100 parts by mass of DY35-796AB (manufactured by Toray Dow Corning Silicone Co., Ltd.) and 30 parts by mass of n-hexane. Sulfur was performed to form a silicone rubber layer having a thickness of 40 μm. On this silicone rubber layer, 100 parts by mass of SIFEL 610 (manufactured by Shin-Etsu Chemical Co., Ltd.), which is a fluorocarbon siloxane rubber precursor, and fluorine-based solvents (m-xylene hexafluoride, perfluoroalkane, perfluoro (2-butyltetrahydrofuran)) (Mixed solvent) After forming a coating film by dip coating a coating solution prepared by 20 parts by mass, primary vulcanization at 120 ° C. for 10 minutes, secondary vulcanization at 180 ° C. for 4 hours, and a thickness of 20 μm A fixing belt having a fluorocarbon siloxane rubber layer was used.

Each electrophotographic print obtained in the treatment A and the treatment B was measured for 20-degree glossiness with a digital variable glossiness meter (manufactured by Suga Test Instruments, UGV-5D) according to JIS Z8741.
FIG. 4 to FIG. 6 show the relationship between the bump water absorption and the glossiness in the treatment A (23 ° C., 50% RH) and the treatment B (23 ° C., 50% RH and 23 ° C., 85% RH environmental conditions).

<Occurrence of blister>
About the image print output by the said process B (23 degreeC, 85% RH environmental conditions), the presence or absence of generation | occurrence | production of a blister was evaluated by visual observation by the following reference | standard.
[Evaluation criteria]
○: No occurrence of blister.
Δ: Some blisters are observed.
X: Generation | occurrence | production of blister is recognized.

表６及び図４〜図６の結果から、実施例１〜４は、処理Ａ及び処理Ｂのいずれにおいても、良好なグレー光沢度を有している。処理Ｂでは、２３℃、８５％ＲＨ環境下での光沢度が、２３℃、５０％ＲＨ環境下での光沢度よりも高いことから高湿条件においてトナー受像層が水を吸水してトナー定着性が向上し、良好なグレー光沢度が得られることが認められる。
なお、比較例３〜４は、処理Ｂにおいて、ブリスターの発生が目視確認された。

From the results of Table 6 and FIGS. 4 to 6, Examples 1 to 4 have good gray glossiness in both the processing A and the processing B. In Process B, the glossiness in an environment of 23 ° C. and 85% RH is higher than the glossiness in an environment of 23 ° C. and 50% RH, so that the toner image-receiving layer absorbs water in a high humidity condition to fix the toner. It can be seen that the properties are improved and good gray gloss is obtained.
In Comparative Examples 3 to 4, the occurrence of blisters was visually confirmed in Process B.

  The electrophotographic image-receiving sheet of the present invention has good toner fixing properties, can form high-quality images with particularly improved glossiness at intermediate density, and can be suitably used in image forming methods.

FIG. 1 is a schematic diagram showing an example of a fixing belt type electrophotographic apparatus of the present invention. FIG. 2 is a schematic view showing an example of the image forming apparatus of the present invention. FIG. 3 is a schematic view showing an example of a cooling and peeling type belt fixing type smoothing processor. FIG. 4 is a graph showing the relationship between the water absorption of the bumps and the glossiness in the treatment A (23 ° C.-50% RH) in Examples. FIG. 5 is a graph showing the relationship between the water absorption of the bumps and the glossiness in the treatment B (23 ° C.-50% RH) in the examples. FIG. 6 is a graph showing the relationship between the water absorption degree of the bump and the glossiness in the treatment B (23 ° C.-85% RH) in Examples.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrophotographic image receiving sheet 12 Toner 13 Fixing belt 14 Heating roller 15 Pressure roller 16 Cooling device 17 Tension roller 18 Electrophotographic image receiving sheet 19 Developing device 25 Belt fixing device 31 Intermediate transfer belt 71 Heating roll 72 Pressure roll 74 Peeling Roll 75 Tension roll 73 Endless belt 77 Cooling heat sink

Claims (11)

An electrophotographic image-receiving sheet comprising a support and a toner image-receiving layer containing at least a thermoplastic resin on the support, wherein the surface of the electrophotographic image-receiving sheet on the toner image-receiving layer side has a bump water absorption of 1 An electrophotographic image-receiving sheet, which is ˜20 g / m ² . The electrophotographic image-receiving sheet according to claim 1, wherein the water absorption of the bump is ² to 15 g / m ² .   The electrophotographic image-receiving sheet according to claim 1, wherein the toner image-receiving layer contains a water-soluble resin.   The electrophotographic image-receiving sheet according to claim 3, wherein the water-soluble resin is at least one selected from a polyalkylene oxide resin, an ester ether resin, and an aqueous nylon resin.   The electrophotographic image-receiving sheet according to any one of claims 1 to 4, wherein the support is selected from base paper, synthetic paper, synthetic resin sheet, coated paper and laminated paper.   6. A belt fixing type comprising: a toner image forming step for forming a toner image on the electrophotographic image receiving sheet according to claim 1; a heating and pressing member for the toner image; a belt member; and a cooling device. An image forming method comprising: a fixing smoothing step of heating and pressurizing using a smoothing processor, cooling and peeling.   The image forming method according to claim 6, wherein the toner image forming step includes a toner image fixing step of fixing the toner image formed on the electrophotographic image receiving sheet with a heat roller.   The image forming method according to claim 6, wherein in the fixing and smoothing step, the toner image surface is heated and pressed to a temperature of 80 ° C. or higher and lower than 180 ° C. and peeled from the belt member at a temperature of 80 ° C. or lower.   9. The image forming method according to claim 6, wherein the belt member has a fluorocarbon siloxane rubber layer formed on a belt support.   9. The image forming method according to claim 6, wherein the belt member is formed by forming a silicone rubber layer on the belt support and a fluorocarbon siloxane rubber layer on the surface of the silicone rubber layer. The image forming method according to claim 9, wherein the fluorocarbon siloxane rubber in the fluorocarbon siloxane rubber layer has at least one of a perfluoroalkyl ether group and a perfluoroalkyl group in the main chain.

Images