JP2007127767A - Electrophotographic image receiving material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic image receiving material capable of obtaining a print of photo-like glossiness by a single fixation processing, and also, having a wide range (fixation adaptive temperature range) between the fixation-feasible lowest temperature (minimum fixation temperature) and the highest temperature not causing hot offset phenomenon. <P>SOLUTION: Regarding the electrophotographic image receiving material having a toner receiving layer on a support body, a heat insulating layer is provided between the support body and the toner receiving layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a novel electrophotographic image receiving material used in electrophotographic image forming equipment such as a copying machine, a printer, and a facsimile machine.

  At present, image forming apparatuses using an electrophotographic method are widely used in offices and the like. Plain paper has been used for this electrophotographic image forming equipment, but for electrophotography that forms high-quality full-color images with the spread and development of multicolor images and full-color image forming methods using electrophotography. Image receiving paper has been developed.

  In recent years, there has been a growing demand for photo-like prints comparable to silver halide photographic prints and inkjet output prints, but color output images by electrophotography are still satisfactory in quality compared to the former prints. The situation is not so far.

  These electrophotographic color prints use toner on the order of several μm as an image forming element. Therefore, the gloss is poor and the amount of toner applied is limited, which is necessary to achieve a photographic image. The current situation is that the density has not been realized, and these improvements are strongly desired for photo-like image output.

  One of the methods for expressing gloss in the formed color image is a support having high smoothness. For example, paper such as cast coated paper or RC paper in which both sides of a paper base are coated with a resin is mainly used. A support as a component has been proposed (see Patent Documents 1 to 3). However, since the paper support retains moisture in the paper, the moisture in the paper is vaporized by heat at the time of fixing and may cause a so-called Lister phenomenon by causing the paper to swell. This is remarkable for paper supports such as cast-coated paper and RC paper. When such a support is used, elimination of blisters is an important issue.

  In order to solve the above-described problem, a method of fixing by cooling and peeling belt fixing is disclosed (Patent Documents 4 and 5). However, with such a fixing method, the apparatus becomes large, the apparatus cost increases, and the conveyance speed must be reduced, but a photo-like gloss cannot be obtained. Further, after fixing, there is disclosed a method for expressing gloss by further embossing on a film or performing belt fixing by a cooling peeling method (see Patent Documents 6 and 7). However, when such fixing process is performed twice or more, the device design becomes complicated as the number of processes increases, and there are problems such as poor versatility. There is a demand for a printing technique that can provide a photo-like image with a feeling.

There are various types of image output devices for electrophotographic processes such as copiers, laser beam printers, LED printers, multi-function printers, etc., with only a fixing unit, such as fixing temperature, fixing speed, and fixing pressure. There are various fixing conditions. In electrophotographic image-receiving materials that can be used for a variety of fixing conditions, the temperature range between the lowest fixable temperature (minimum fixing temperature) and the highest temperature range (fixing adaptive temperature range) where hot offset does not occur. Is desirable. As a method for expanding the minimum fixing temperature and the fixing adaptation temperature range, the technical means related to the toner have been proposed so far (see Patent Documents 8 and 9). Naturally, there is a limit, and there is a close relationship between toner and electronic process equipment, and it is difficult to change the toner easily. The emergence of a method for expanding the range of application in electronic process equipment is desired.
JP 2000-3062 A JP 2000-10327 A JP-A-2005-43474 JP 2004-126427 A JP 2004-133324 A JP 2000-66466 A JP 2005-4038 A JP 2000-122334 A JP 2000-187358 A

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and its object is to obtain a photo-like glossy print by a single fixing process, as well as the lowest fixing temperature (minimum fixing temperature) and the hot offset phenomenon. An object of the present invention is to provide an electrophotographic image-receiving material having a wide maximum temperature range (fixing adaptation temperature range) in which no occurrence occurs.

  The above object of the present invention is achieved by the following configurations.

  1. An electrophotographic image receiving material having a toner receiving layer on a support, wherein the electrophotographic image receiving material has a heat insulating layer between the support and the toner receiving layer.

  2. 2. The electrophotographic image receiving material as described in 1 above, wherein the toner receiving layer contains a thermoplastic resin.

  3. 3. The electrophotographic image receiving material as described in 2 above, wherein the thermoplastic resin is a thermoplastic resin having compatibility with a binder resin of toner.

  4). 4. The electrophotographic image receiving material according to any one of 1 to 3, wherein the heat insulating layer has a void structure.

  5. 5. The electrophotographic image receiving material according to any one of 1 to 4, wherein the heat insulating layer has a porosity of 40% or more.

  6). 6. The electrophotographic image-receiving material according to any one of 1 to 5, wherein the heat insulating layer has a thickness of 30 μm or more.

  According to the present invention, a photo-like glossy print can be obtained by a single fixing process, and a minimum temperature that can be fixed (minimum fixing temperature) and a maximum temperature range that does not cause hot offset phenomenon (fixing adaptive temperature range). A wide electrophotographic image-receiving material could be provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  As a result of intensive studies in view of the above problems, the inventor of the present invention has a heat insulating layer between the support and the toner receiving layer in the electrophotographic image receiving material having the toner receiving layer on the support. With the electrophotographic image receiving material, a photo-like glossy print can be obtained with a single fixing process, and the lowest fixing temperature (minimum fixing temperature) and the highest temperature range that does not cause hot offset phenomenon (fixing adaptation) It has been found that an electrophotographic image-receiving material having a wide temperature range can be realized, and the present invention has been achieved.

  The details of the electrophotographic image receiving material of the present invention will be described below.

《Insulation layer》
The electrophotographic image receiving material of the present invention is characterized in that a heat insulating layer is provided between the support and the toner receiving layer.

  By providing the heat insulating layer according to the present invention below the toner receiving layer, the thermal energy applied from the fixing roller or the like during fixing is blocked from diffusing, and the high temperature state of the toner receiving layer is maintained. Glossy prints can be obtained by dissolving and smoothing the landed toner particles, or by embedding them in the toner receiving layer, and the toner can be melted uniformly to fix the toner even at a low fixing temperature. In addition, the hot offset phenomenon, which is a problem at a high fixing temperature, can be solved by high bleed-out of the wax in the toner, so that a wide fixable temperature range can be obtained.

  In general, the heat insulating layer is a layer containing a constituent material having low thermal conductivity, and includes a method using a resin having low thermal conductivity, or a method using a material containing an air layer or bubbles. In the present invention, a heat insulating layer having a high porosity (void capacity) is preferable.

  The porosity of the heat insulating layer according to the present invention may be 30% or more, preferably 40% or more, particularly preferably 50% or more and 90% or less.

  As a material for forming the heat insulating layer having a high porosity defined in the present invention, a material obtained by dispersing foamed plastic, hollow particles, or porous particles in a resin layer is used.

  Foamable plastic is a hollow plastic filler containing a heat-fusible substance as a shell and containing a low-boiling solvent inside, and foams when heated. Examples of the thermoplastic resin that forms the shell of the plastic filler include polystyrene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, polyacrylic acid ester, polyacrylonitrile, polybutadiene, and copolymers thereof. Examples of the blowing agent contained in the shell include propane, isobutane, neopentane, and petroleum ether. For example, there are Micropearl manufactured by Matsumoto Yushi Co., Ltd. and Expandel manufactured by Kemanode.

  As the hollow particles, there are micro hollow bodies formed of various materials such as glass, ceramics, plastics, and the like. As the glass micro hollow bodies, borosilicate glass microspheres, for example, Microsel M. manufactured by Grapabell, Inc. are available. As the aluminosilicate micro hollow body, there is a premix for low foam injection molding and standard injection molding such as Fillite manufactured by Nippon Philite.

  When organic hollow particles are used for the heat insulation layer, examples of the hollow particles used in the present invention include thermally expandable hollow particles and capsule-shaped hollow polymers. The heat-expandable hollow particles are hollow particles having a thermoplastic material such as vinylidene chloride-acrylonitrile copolymer as a wall material, and a material containing a heat-expandable gas such as propane, n-butane and isobutane inside the particle. It is. The capsule-like hollow polymer is a polymer that uses a resin such as styrene-acrylic as a wall material, contains water therein, and evaporates into water when dried to form hollow particles. The hollow particles as described above generally have a particle size of about 0.1 to 100 μm, but the particle size of the hollow particles used in the present invention is preferably 0.2 to 10 μm, more preferably 0.00. 3-5 μm. If it is less than 0.3 μm, a sufficient heat insulating effect as hollow particles cannot be obtained, and if it exceeds 10 μm, the smoothness is significantly lowered.

  The particle diameter referred to in the present invention can be determined by a known method, and can be measured using, for example, particle measurement with an electron microscope or a laser diffraction particle size distribution measuring apparatus.

  The hollowness of the hollow particles is a ratio of the outer diameter to the inner diameter of the hollow particles and is expressed by the following formula.

Hollowness (%) = (inner diameter of hollow particles / outer diameter of hollow particles) × 100
Here, the outer diameter / inner diameter of the hollow particles can be determined by particle measurement with an electron microscope.

  The resin for dispersing and holding the hollow particles is not particularly limited. For example, styrene-butadiene rubber, styrene-methyl methacrylate-butadiene rubber, acrylic resin, acrylic-styrene resin, acrylic-maleic acid resin, acrylic-vinyl acetate. Resin, emulsion type synthetic resin such as ethylene-vinyl acetate resin, water-soluble polymer such as polyvinyl alcohol, starch, casein, gelatin, carboxymethylcellulose, polyethylene oxide and the like.

  The porous particles in the present invention are porous particles having pores on the particle surface, and both inorganic porous particles and organic porous particles can be used.

  The inorganic porous particles are composed of amorphous silica, anhydrous silica, aluminum silicate, magnesium silicate, zinc silicate, calcium silicate, hydrotalcite, zeolite, satin white, titanium oxide, aluminum oxide. , Magnesium oxide, calcium carbonate, calcium sulfate, barium sulfate, diatomaceous earth, kaolin, talc, acidic clay, activated clay, bentonite and the like.

  The organic porous particles used in the present invention may be those obtained by an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, or other polymerization methods, or may be those obtained by pulverizing a massive porous resin. . The resin component is not particularly limited, for example, polyester resin, methacrylic resin, polycarbonate resin, styrene copolymer resin, vinyl chloride resin, polypropylene resin, and blends thereof. Further, the means for making the resin particles porous or obtaining a porous resin is not particularly limited. Among them, organic porous particles obtained by emulsion polymerization are preferable, and for example, particle aggregate emulsion particles disclosed in JP-A-2-70741 are preferable. Furthermore, the structure at the time of drying described in JP-A-5-222108 has one or more through-holes connecting the inside from the surface layer portion of the particles, and the particle diameter is 0.1 to 5.0 μm. More preferably, it is a multilayer structure emulsion particle.

  The particle diameter of the organic porous particles is 0.05 to 50 μm, preferably 0.1 to 20 μm, more preferably 0.2 to 10 μm. If the particle diameter is less than 0.05 μm, it is difficult to make the particles porous. The particle diameter can be measured by the same method as for the hollow particles.

  Whether or not the porous particles are made porous can be apparently seen using an electron microscope or the like, but the degree of porosity can be confirmed by measuring the specific surface area with a mercury porosimeter. it can. Moreover, it can also confirm by the measurement of the oil absorption amount described in JIS K-5101. This utilizes the fact that a larger amount of oil is sucked than non-porous particles of the same component and the same particle size due to the capillary action of pores existing on and inside the particle.

  The thickness of the heat insulating layer according to the present invention is generally 20 μm or more, but is preferably 30 μm or more from the viewpoint of exerting the effects of the present invention, and is preferably 100 μm or less from the viewpoint of productivity.

<Toner-receiving layer>
The toner receiving layer according to the present invention is not particularly limited, but is preferably composed of a thermoplastic resin.

  Examples of the thermoplastic resin applicable to the toner receiving layer according to the present invention include the following thermoplastic resins.

(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, etc.
(B) Those having an ester bond For example, terephthalic acid, isophthalic acid, maleic acid, fumaric acid, phthalic acid, adipic acid, sebacic acid, azelaic acid, abietic acid, succinic acid, trimellitic acid, pyromellitic acid, etc. An acid component (these dicarboxylic acid components may be substituted with a sulfonic acid group, a carboxyl group, etc.) and a diether derivative of ethylene glycol, diethylene glycol, propylene glycol, bisphenol A, bisphenol A (for example, ethylene of bisphenol A) Alcohol components such as oxide 2 adducts, bisphenol A propylene oxide 2 adducts, etc.), bisphenol S, 2-ethylcyclohexyldimethanol, neopentyl glycol, cyclohexyldimethanol, glycerin, etc. Polyester resin or polymethacrylic acid resin such as polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate, etc. obtained by condensation with a hydroxyl group etc. may be substituted in the alcohol component of Ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, styrene-methacrylic acid ester copolymer resin, vinyl toluene acrylate resin and the like. Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862. Commercially available products include Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130, etc. manufactured by Toyobo, Kao's Tufton NE-382, Tufton U-5, ATR- 2009, ATR-2010, etc., Unitika Eritel UE3500, UE3210, XA-8153, etc., Nippon Synthetic Chemical Polyester TP-220, R-188, etc. can be mentioned.

(C) Polyurethane resin, etc.
(D) Polyamide resin, urea resin, etc.
(E) Polysulfone resin, etc.
(F) Polyvinyl chloride resin, polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, etc.
(G) Polyvinyl butyral, etc., polyol resin, ethyl cellulose resin, cellulose resin such as cellulose acetate resin, etc.
(H) Polycaprolactone resin, styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin and the like.

  Each of the above thermoplastic resins may be used alone, or two or more of these thermoplastic resins may be mixed and used.

  When coated paper is used as the support described later, the thermoplastic resin to be applied is, in particular, polyethylene, such as high-density polyethylene or low-density polyethylene, and also other polyolefins such as polypropylene, polyester, etc. Etc. can be preferably used. These resins may be used in combination.

  The toner receiving layer may be a single layer or may be composed of two or more layers. The film thickness of the thermoplastic resin constituting the toner receiving layer is generally from 0.1 to 50 μm, preferably from 0. 5 to 10 μm.

  The glass transition point of the thermoplastic resin used in the toner receiving layer according to the present invention is 0 ° C. or higher, preferably 20 ° C. or higher, and the thermal conductivity is preferably 0.3 W / m · K or lower. The thermal conductivity of the thermoplastic resin is, for example, “New edition plastic material reader” (Industry Research Committee, published April 1, 1993, new edition 4 printing), “Plastic molding data book” (Nikkan Kogyo Shimbun, 1988). 1st edition issued in March) and “Plastics Data Book” (Industry Research Committee, issued in December 1999, first edition issued).

  As the thermoplastic resin used in the toner receiving layer according to the present invention, it is preferable to select a resin having high compatibility with the binder resin constituting the toner to be received from the viewpoint that the effects of the present invention can be further exhibited.

  To be compatible with the toner binder resin in the present invention means that the thermoplastic resin of the toner receiving layer and the toner binder resin do not form a boundary in the image after fixing. As a method for evaluating the compatibility of the toner with the binder resin, for example, a method in which the solubility parameter described in JP-A-2-263642 is used for measurement is described. A method for measuring the toner inclination angle can be mentioned.

  As a method for measuring the melted toner inclination angle, after forming a toner disk, the toner receiving layer composed of a thermoplastic resin set to a predetermined temperature is closely contacted with the toner disk, and the toner disk is melted. Rapid cooling and solidification. Using this contact angle measuring device manufactured by Kyowa Interface Chemical Co., Ltd., the angle of the bottom of the toner after the toner is solidified is measured twice, and the average value is taken as the molten toner inclination angle.

  When the thermoplastic resin is selected from the viewpoint of the molten toner inclination angle, it is preferable to use a resin having a toner inclination angle of 40 degrees or less between the toner used for color image formation and the thermoplastic resin. The resin of the transparent resin layer having a molten toner inclination angle of 40 degrees or less includes polyester resin, styrene-acrylic ester resin, epoxy resin, polyurethane resin, polymethyl methacrylate resin, vinyl chloride resin, vinyl chloride-vinyl acetate copolymer. And other thermoplastic resins. Particularly preferred is a resin of the same type as the main resin of the toner (a resin containing 50% by mass or more based on the binder resin). That is, if the main resin of the toner is a polyester resin, a polyester resin is used as the resin of the toner receiving layer, and if the main resin of the toner is a styrene-acrylic ester resin, a styrene-acrylic ester resin is used as the resin of the toner receiving layer. Is preferred.

<Other additives for toner receiving layer and heat insulating layer>
In addition to the above-described additives, various additives can be used for the toner image-receiving layer or the heat-insulating layer according to the present invention for the purpose of improving the thermodynamic characteristics.

  Such additives can be appropriately selected according to the purpose, for example, plasticizers, fillers, crosslinking agents, charge control agents, conductive agents, pigments, surfactants, dyes, humidity control agents, Matting agents and the like can be mentioned.

  The plasticizer has a function of adjusting the flow or softening of the toner receiving layer by heat or pressure when fixing the toner. Plasticizers include "Chemical Handbook" (edited by the Chemical Society of Japan, Maruzen), "Plasticizers-Theory and Applications-" (written by Koichi Murai, Koshobo), "Research on plasticizers" It can be selected with reference to "Research" (edited by Polymer Chemistry Association) and "Handbook Rubber / Plastic Compounded Chemicals" (edited by Rubber Digest).

  Moreover, as a filler, a well-known thing can be used as a reinforcing agent for resin, a filler, and a reinforcing material, An organic and inorganic filler are preferable. The filler can 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. it can.

  Examples of the crosslinking agent include an epoxy group, an isocyanate group, an aldehyde group, an active halogen group, an active methylene group, an acetylene group, and other compounds having two or more known reactive groups in the molecule as a reactive group. Further, a compound having two or more groups capable of forming a bond by ionic bond, coordinate bond, or the like is also included. Examples of the crosslinking agent also include known compounds such as coupling agents for resins, curing agents, polymerization agents, polymerization accelerators, coagulants, film-forming agents, film-forming aids, and the like.

  The charge adjusting agent can be used for the purpose of adjusting toner transfer, adhesion, etc., and preventing charging adhesion of electrophotographic receiving paper. As the charge control agent, any of conventionally known antistatic agents and charge control agents can be used. Surfactants such as cationic surfactants, anionic surfactants, amphoteric surfactants and nonionic surfactants In addition, a polymer electrolyte, a conductive metal oxide, and the like can be used.

Examples of the conductive agent include metal oxides such as ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, and MoO ₃ . These may be used alone or in combination of two or more.

  Examples of the pigment include fluorescent whitening agents, white pigments, colored pigments, and dyes for the purpose of improving image quality, particularly whiteness. The fluorescent whitening agent is a compound that has absorption in the near ultraviolet region and emits fluorescence at 400 to 500 nm. Examples of the fluorescent brightener include stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, pyrazoline compounds, carbostyril compounds, and the like.

  Various known dyes can be used as the dye, and examples thereof include oil-soluble dyes. Examples of oil-soluble dyes include anthraquinone compounds and azo compounds.

The whiteness of the toner-receiving layer according to the present invention is not particularly limited and can be appropriately selected according to the purpose, but is preferably higher. The whiteness, L ^* value is preferably 80 or more in ^{CIE 1976 (L * a * b} *) color space, and more preferably 85 or more, particularly preferably 90 or more. The white color is preferably as neutral as possible. As a white color, the value of (a ^* ) ² + (b ^* ) ^{2 in} the L ^* a ^* b ^* space is preferably 50 or less, more preferably 18 or less, and particularly preferably 5 or less.

  The smoothness of the toner receiving layer according to the present invention is not particularly limited and can be appropriately selected according to the purpose, but is preferably higher. Further, the smoothness is not particularly limited and can be appropriately selected according to the purpose, but is preferably higher. As the smoothness, the arithmetic average roughness (Ra) is preferably 3 μm or less, more preferably 1 μm or less, and more preferably 0.5 μm or less in the entire region from white without toner to black having the maximum density. It is particularly preferred. The arithmetic average roughness can be measured based on JIS B 0601, B 0651, and B 0652.

The surface electrical resistance of the toner receiving layer according to the present invention is preferably 1 × 10 ⁶ to 1 × 10 ¹⁵ Ω (25 ° C., 65% RH), and other than the toner receiving layer according to the present invention. The surface electrical resistance in the layer is also preferably 1 × 10 ⁶ to 1 × 10 ¹⁵ Ω (25 ° C., 65% RH condition).

  A matting agent can be added to the toner receiving layer according to the present invention. There is no restriction | limiting in particular as a mat agent, According to the objective, it can select suitably, For example, a solid particle etc. are mentioned. The solid particles can be classified into inorganic particles and organic particles.

  A slipping agent can be added to the toner receiving layer according to the present invention. Examples of the slip agent include various known ones such as higher alkyl sulfate, higher fatty acid higher alcohol ester, carbowax, higher alkyl phosphate ester, silicone compound, modified silicone, curable silicone, and the like. Polyolefin wax, fluorine oil, fluorine wax, carnauba wax, microcrystalline wax, silane compound, and the like.

<Support>
As a support according to the present invention, as long as it can withstand the fixing temperature and can satisfy the requirements in terms of smoothness, whiteness, slipperiness, friction, antistatic properties, dents after fixing, etc. There is no restriction in particular, and it can be appropriately selected according to the purpose. In general, “Photographic Engineering Basics-Silver Salt Photography” edited by the Japan Photography Society, published by Corona Co., Ltd. (Showa 54) (223) ) To (240) pages, and photographic supports such as synthetic polymers (films).

  Specific examples of the support include synthetic paper (polyolefin-based, polystyrene-based synthetic paper), high-quality paper, art paper, (double-sided) coated paper, (double-sided) cast-coated paper, and synthetic resin pulp such as polyethylene and natural pulp. Paper, Yankee paper, baryta paper, wallpaper, backing paper, synthetic resin or emulsion impregnated paper, synthetic rubber latex impregnated paper, synthetic resin internal paper, paperboard, cellulose fiber paper, polyolefin coated paper (especially polyethylene) Paper coated on both sides), various plastic films or sheets such as polyethylene terephthalate, polystyrene methacrylate, polyethylene naphthalate, etc., and treatment to give white reflectivity to the plastic film or sheet (for example, titanium oxide into the film) Etc.) Films or sheets, fabrics, metals, such as glasses and the like, polyolefin-coated paper (paper, particularly coated on both sides with polyethylene), cast-coated paper is preferred.

As thickness of a support body, it is 25-300 micrometers normally, 50-260 micrometers is preferable and 75-220 micrometers is more preferable. The stiffness and smoothness of the support are not particularly limited and may be appropriately selected depending on the intended purpose. However, for a photographic image receiving paper, a support close to a color silver salt photograph is preferable. The density of the support is preferably 0.7 g / cm ³ or more from the viewpoint of fixing performance.

  The thermal conductivity of the support is not particularly limited and may be appropriately selected depending on the intended purpose. From the viewpoint of fixing performance, it is 2.1 kW / under 20 ° C. and 65% relative humidity. It is preferably m · h · ° C. or higher. The thermal conductivity can be measured by a method described in JP-A-53-66279 using a transfer paper conditioned according to JIS P8111.

  Various additives appropriately selected according to the purpose can be added to the support according to the present invention within a range that does not impair the effects of the present invention. Examples of additives include whitening agents, conductive agents, fillers, pigments such as titanium oxide, ultramarine blue, and carbon black, and dyes.

  In addition, one or both surfaces of the support according to the present invention can be subjected to various surface treatments and undercoating treatments for the purpose of improving the adhesion with a layer provided thereon. Examples of the surface treatment include a glossy surface, or a fine surface, mat surface, or silk surface surface forming treatment, corona discharge treatment, flame treatment, glow discharge treatment, and plasma treatment described in JP-A-55-26507. An activation process etc. are mentioned. Examples of the undercoating treatment include the method described in JP-A No. 61-84443. These treatments may be performed alone, or may be subjected to an activation treatment after performing the above-described molding treatment or the like, and may further be subjected to a primer treatment after a surface treatment such as an activation treatment, Each of these means can be arbitrarily combined.

  A hydrophilic binder, a semiconductive metal oxide such as alumina sol or tin oxide, and carbon black or other antistatic agent may be applied to the support, the front surface or the back surface of the support, or a combination thereof. . Specific examples of such a support include those described in JP-A No. 63-220246.

《Other constituent layers》
In the electrophotographic image receiving material of the present invention, in addition to the toner receiving layer and the heat insulating layer described above, other constituent layers can be provided. The other constituent layers are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a surface protective layer, an intermediate layer, an undercoat layer, a cushion layer, a charge control (prevention) layer, a reflective layer, and a color. Examples include a taste preparation layer, a storage stability improving layer, an adhesion preventing layer, an anti-curl layer, and a smoothing layer. These may have a single layer structure or a laminated structure. When the support is a reflective support and is a reflective electrophotographic image receiving material in which the toner receiving layer according to the present invention is provided on the support, each layer provided on the support needs to be transparent. Rather, it is preferably white.

  As the opacity of the electrophotographic image-receiving material of the present invention, the value measured by the method defined in JIS P 8138 is preferably 85% or more, more preferably 90% or more.

  In the electrophotographic image-receiving material of the present invention, for the purpose of imparting backside output suitability, improving backside output image quality, improving curl balance, imparting writing properties, inkjet, other print suitability, improving device passability, etc. A back layer can be provided on the side opposite to the side on which the image receiving layer is provided. The back layer may have the same configuration as the image receiving layer side in order to improve the double-sided output suitability. In the back layer, the above-mentioned various additives can be used, and it is particularly preferable to use the above-mentioned matting agent, slip agent, charge adjusting agent and the like. The back layer may be a single layer or two or more layers. In addition, when releasing oil is used for a fixing roller or the like to prevent offset at the time of fixing, it is preferable that the back surface has oil absorbability.

  In the electrophotographic image-receiving material of the present invention, an adhesion improving layer can be provided for the purpose of improving the adhesion between the support, the heat insulating layer, the toner receiving layer, and other constituent layers.

  In the electrophotographic image-receiving material of the present invention, various additives can be used for the purpose of improving the stability of the output image and improving the stability of the image-receiving layer itself. Examples of such additives include various known antioxidants, anti-aging agents, ultraviolet absorbers, light stabilizers, deterioration inhibitors, ozone deterioration inhibitors, preservatives, and antifungal agents.

  The electrophotographic image-receiving paper of the present invention can be used for image formation with an electrophotographic toner by an electrophotographic method, and can be suitably used for color image formation with an electrophotographic color toner.

<Electrophotographic toner>
The toner used in the present invention is not particularly limited as long as it is a known electrophotographic toner, and the toner production method is not particularly limited as long as it is a known production method such as a pulverization method or a polymerization method. In order to produce the effect of the above, a monomer is emulsion-polymerized in a suspension polymerization method or a liquid obtained by adding an emulsion of necessary additives to produce fine polymer particles, and then an organic solvent, A production method in which an aggregating agent or the like is added to associate is preferable. At the time of association, a method of preparing by mixing with a dispersion liquid such as a release agent or a colorant necessary for the composition of the toner and making it associate, or a toner component such as a release agent or a colorant in the monomer A method of emulsion polymerization after dispersion is preferred. Here, the association means that a plurality of resin particles and colorant particles are fused.

  Although it does not specifically limit as a manufacturing method of a suspension polymerization method, The following manufacturing methods can be raised.

  That is, various constituent materials such as a colorant and, if necessary, a release agent, a charge control agent, and a polymerization initiator are added to the polymerizable monomer, and then a homogenizer, a sand mill, a sand grinder, an ultrasonic disperser, etc. Various constituent materials are dissolved or dispersed in the polymerizable monomer. The polymerizable monomer in which these various constituent materials are dissolved or dispersed is dispersed in oil droplets having a desired size as a toner in an aqueous medium containing a dispersion stabilizer using a homomixer or a homogenizer. Thereafter, the stirring mechanism is transferred to the reaction apparatus which is the aforementioned stirring blade, and the polymerization reaction is advanced by heating. After completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare the toner of the present invention.

  Further, as a method for producing the toner according to the present invention, a method of preparing by fusing resin particles in an aqueous medium can also be mentioned. The method is not particularly limited, and examples thereof include methods described in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904. That is, a method of associating a plurality of dispersed particles of constituent materials such as resin particles and a colorant, or a plurality of fine particles composed of a resin and a colorant, particularly after dispersing them in water using an emulsifier, the critical aggregation concentration The toner of the present invention is prepared by adding the above flocculant and salting out, and simultaneously heat-melting the formed polymer itself at a temperature equal to or higher than the glass transition temperature and heat-drying the particles in a fluid state while containing water. Can be formed. Here, an organic solvent that is infinitely soluble in water may be added simultaneously with the flocculant.

  As the resin component of the toner, a known resin can be used, but generally, a polyester resin, a styrene-acrylic resin, or the like can be mainly used. When an image is formed on the coating layer, it is preferable to select a resin having high compatibility with a resin component such as an adhesive contained in the coating layer as the resin component of the toner. From this point of view, as the resin component of the toner, one or a mixture of two or more of polyester resin, styrene-acrylic ester resin, styrene-methacrylic ester resin, etc. may be used depending on the purpose. Is preferred.

  The volume average particle diameter of the toner is preferably in the range of 2 to 10 μm, and more preferably in the range of 3 to 9 μm. When the volume average particle diameter of the toner is less than 2 μm, the chargeability tends to be insufficient and the developability may be deteriorated. On the other hand, when it exceeds 10 μm, the resolution of the image may be deteriorated. Therefore, it is not preferable respectively.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
<Production of support>
[Preparation of Support A]
A white base paper 1 having a basis weight of 150 g / m ² composed of 50% by mass sulfate method bleached hardwood pulp (LBKP) and 50% by mass sulfate method bleached softwood pulp (NBSP) was prepared.

Polyethylene was melt-extruded at 300 ° C. as a back surface resin layer on the back surface of the white base paper 1 to coat the back laminate layer 1 of 15 g / m ² .

Next, as a surface resin layer on the surface side, 91% by mass of polyethylene and 9% by mass of rutile type titanium oxide were kneaded, and then coated with 20 g / m ² of water-resistant resin layer 1 by melt extrusion lamination at 300 ° C. A support A having a resin coating layer was prepared.

[Preparation of Support B]
In the production of the support A, the amount of polyethylene applied to the back surface resin layer was changed to 40 g / m ² , and instead of the water-resistant resin layer 1 as the surface resin layer, 89% by mass of polyethylene, anatase-type titanium oxide 11 except that was coated with a water-resistant resin layer 2 of 50 g / m ² by a melt extrusion lamination at 300 ° C. mass% after kneading in the same manner, to prepare a support B.

[Preparation of Support C]
The following back surface resin layer and surface resin layer were coated on the front and back surfaces of the white base paper 1 to prepare a support C.

  Back surface resin layer: After a polypropylene resin was melt-extruded at 300 ° C., a biaxially stretched polypropylene resin sheet having a thickness of 20 μm was fabricated using a flat film method sequential biaxial stretching apparatus. Next, low-density polyethylene melt-extruded with a thickness of 5 μm as an adhesive layer was laminated between a white base paper and a polypropylene resin sheet, and then niped to form a back resin layer.

  Surface resin layer: A polypropylene resin layer kneaded with 90% by mass of polypropylene and 10% by mass of anatase-type titanium oxide is melt-extruded at 300 ° C. and then biaxially stretched with a thickness of 20 μm using a flat film method sequential biaxial stretching apparatus. A polypropylene resin sheet was produced. Next, a low-density polyethylene melt-extruded with a thickness of 5 μm as an adhesive layer was laminated between a white base paper and a polypropylene resin sheet and then niped to form a surface resin layer.

[Preparation of Support D]
Sulfate method bleached hardwood pulp (LBKP) 90% by weight, sulfate method bleached softwood pulp (NBSP) 10% by weight, with respect to the pulp, 0.7% cationic starch, 0.07% alkenyl succinic anhydride, A raw material prepared by adding 20% heavy calcium carbonate and 1% band is made with a long paper machine, and an aqueous solution containing polyacrylamide and alkyl ketene dimer as a surface sizing agent is dried on both sides in a size press. treated so as to be 0.9 g / m ² to give a white base paper 2 after drying basis weight 170 g / m ^2.

Separately, 0.1% by mass of sodium polyacrylate was added to a blend of 70% by mass of kaolin and 30% by mass of light calcium carbonate, and a 65% by mass pigment slurry was prepared with a courseless disperser. To this slurry, 10% by mass of casein and 10% by mass of styrene-butadiene copolymer latex were added, and water was further added to prepare a coating solution having a solid content concentration of 50%. This coating liquid is applied to the surface side of the white base paper 2 with a reverse roll coater so that the dry mass becomes 20 g / m ^2, and then press-dried to a cast dryer at 100 ° C. to form a support D which is cast-coated paper. Was made.

[Preparation of Support E]
An antistatic layer made of a tin oxide sol was provided on the back side of white polyethylene terephthalate (PET) having a thickness of 170 μm.

<Production of electrophotographic image receiving material>
[Production of Samples 101 to 105]
Polyester resin pellets having a Tg of 67 ° C. are dissolved in a toluene / methyl ethyl ketone mixed solvent as a toner receiving layer a on each surface side of the prepared supports A to E, and the film thickness after drying using a wire bar is 8 μm. It applied and dried so that it might become, and samples 101-105 were produced.

[Production of Samples 106 to 110]
Each surface side of the prepared supports A to E is subjected to a corona discharge treatment according to a conventional method, and then the toner coating layer b is coated with the following coating solution using a wire bar so that the film thickness after drying is 12 μm. The sample 106-110 was produced by apply | coating and drying.

(Toner-receiving layer b)
Polyester aqueous dispersion (Vaironal MD-1100, Toyobo) 50% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 10% by mass
Polyethylene oxide aqueous solution (solid concentration 3%) 10% by mass
30% by weight of water
[Production of Samples 111 to 115]
Each surface side of the prepared supports A to E is subjected to a corona discharge treatment according to a conventional method, and then the toner coating layer c is coated with the following coating solution using a wire bar so that the film thickness after drying is 6 μm. The sample 111-115 was produced by applying and drying.

(Toner-receiving layer c)
Acrylic resin water dispersion (Mobile 747, Nichigo Mobile) 40% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 20% by mass
Gelatin aqueous solution (solid concentration 8%) 15% by mass
25% by weight of water
[Production of Samples 116 to 120]
Each surface side of the prepared supports A to E is subjected to a corona discharge treatment according to a conventional method, and then the toner coating layer c is coated with the following coating solution using a wire bar so that the film thickness after drying is 6 μm. The sample 116-120 was produced by applying and drying.

(Toner-receiving layer d)
Resin water dispersion (Zyxen, manufactured by Sumitomo Seika Co., Ltd.) 50% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 20% by mass
Gelatin aqueous solution (solid concentration 8%) 15% by mass
25% by weight of water
[Production of Samples 121 to 125]
In the preparation of the samples 101 to 105, the following heat insulating layer v was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 25 μm, dried, and then the toner receiving layer a was applied. Samples 121 to 125 were produced in the same manner except for the above.

(Heat insulation layer v)
Thermally expansible micro hollow body (Microsphere F-30, manufactured by Matsumoto Yushi Seiyaku) 15% by mass
Polyvinyl butyral 5% by mass
56% by weight of ethyl alcohol
Toluene 24% by mass
The porosity of the heat insulating layer v was 45%.

[Production of Samples 126 to 130]
In the preparation of the samples 106 to 110, the following heat insulating layer w was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 55 μm, dried, and then the toner receiving layer b was applied. Samples 121 to 125 were produced in the same manner except for the above.

(Insulation layer w)
Spherical porous silica particles (Syrosphere 1501, manufactured by Fuji Silysia Chemical) 20% by mass
Gelatin 5% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 5% by mass
70% by weight of water
In addition, the porosity of the heat insulation layer w was 60%.

[Production of Samples 131 to 135]
In the preparation of Samples 111 to 115, the following heat insulating layer x was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 26 μm, dried, and then the toner receiving layer c was applied. Samples 131 to 135 were prepared in the same manner except for the above.

(Insulation layer x)
Hollow particle dispersion (Lopek HP1055, manufactured by Rohm & Haas) 50% by mass
Gelatin 3% by mass
Dichloro-S-triazine aqueous solution (4%) 2% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 5% by mass
40% by weight of water
The porosity of the heat insulating layer x was 49%.

[Production of Samples 136 to 140]
In the preparation of Samples 111 to 115, the following heat insulating layer y was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 34 μm and dried, and then the toner receiving layer c was applied. Samples 136 to 140 were produced in the same manner except for the above.

(Heat insulation layer y)
Hollow particle dispersion (MH5055, manufactured by Zeon Corporation) 50% by mass
Gelatin 3% by mass
Dichloro-S-triazine aqueous solution (4%) 2% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 5% by mass
40% by weight of water
The porosity of the heat insulating layer y was 51%.

[Production of Samples 141 to 145]
In the preparation of Samples 111 to 115, the following heat insulating layer z was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 37 μm, dried, and then the toner receiving layer c was applied. Samples 141 to 145 were produced in the same manner except for the above.

(Heat insulation layer z)
Hollow particle dispersion (Lopek HP-1055, manufactured by Rohm & Haas) 50% by mass
Gelatin 3% by mass
Dichloro-S-triazine aqueous solution (4%) 2% by mass
Dioctyl sodium sulfosuccinate aqueous solution (solid content 1%) 5% by mass
40% by weight of water
In addition, the porosity of the heat insulation layer z was 65%.

[Production of Samples 146 to 150]
In Samples 116 to 120, the heat-insulating layer y was applied on the surface side of each support with a wire bar so that the average film thickness after drying was 34 μm and dried, and then a toner receiving layer c was applied. Samples 146 to 150 were produced in the same manner except for the above.

[Production of Samples 151 and 152]
In the sample 116, the same procedure was applied except that the heat insulating layer z was coated on the surface side of the support A with a wire bar so that the average film thickness after drying was 55 μm, dried, and then the toner receiving layer c was coated. Sample 151 was prepared, and in Sample 116, the heat insulating layer z was applied to the surface side of the support A with a wire bar so that the average film thickness after drying was 90 μm and dried, and then the toner receiving layer c was formed. A sample 152 was produced in the same manner except that it was applied.

<Evaluation of electrophotographic image-receiving material>
Image formation was performed according to the following method using Samples 101 to 152, which were the electrophotographic image receiving materials prepared above, and plain paper (First Class paper manufactured by Konica Minolta Business Technology).

[Preparation of toner for evaluation]
(Preparation of binder resin particles for toner)
<Preparation of Latex 1>
(1) Preparation of core particles (first-stage polymerization): Preparation of latex (1H) An anionic surfactant [C ₁₀ was placed in a 5000 ml separable flask equipped with a stirrer, a temperature sensor, a condenser, and a nitrogen introducing device. A surfactant solution (aqueous medium) in which 7.08 g of H ₂₁ (OCH ₂ CH ₂ ) ₂ OSO ₃ Na] was dissolved in 3010 g of ion-exchanged water was charged, and the mixture was stirred while stirring at a rate of 230 rpm under a nitrogen stream. The temperature was raised to 80 ° C.

  To this surfactant solution, an initiator solution in which 1.5 g of a polymerization initiator (potassium persulfate: KPS) was dissolved in 200 g of ion-exchanged water was added, the temperature was adjusted to 75 ° C., 80 g of styrene, and n-butyl. A monomer mixture composed of 16 g of acrylate, 4 g of methacrylic acid, and 3.0 g of n-octyl-3-mercaptopropionate is dropped over 1 hour, and this system is heated and stirred at 75 ° C. for 2 hours. Polymerization (first stage polymerization) was performed to prepare a latex. This is referred to as “latex (1H)”.

(2) Formation of intermediate layer (second stage polymerization): Preparation of latex (1HM) In a flask equipped with a stirrer, 120 g of styrene, 24 g of n-butyl acrylate, 6 g of methacrylic acid, n-octyl-3-mercaptopropion 98.0 g of the following crystalline substance A was added to a monomer mixture composed of 4.5 g of an acid ester, and heated to 90 ° C. and dissolved to prepare a monomer solution.

  On the other hand, a surfactant solution in which 1.6 g of an anionic surfactant (supra) is dissolved in 2700 ml of ion-exchanged water is heated to 98 ° C., and this surfactant solution is a dispersion of core particles. After adding 28 g of the latex (1H) in terms of solid content, the monomer of the crystalline compound A is obtained by a mechanical disperser “CLEARMIX” (manufactured by M Technique Co., Ltd.) having a circulation path. The solution was mixed and dispersed for 8 hours to prepare a dispersion (emulsion) containing emulsified particles (oil droplets) having a dispersed particle size (284 nm).

  Next, an initiator solution prepared by dissolving 4.5 g of a polymerization initiator (KPS) in 240 ml of ion-exchanged water and 750 ml of ion-exchanged water are added to this dispersion (emulsion), and this system is heated at 98 ° C. Polymerization (second stage polymerization) was performed by heating and stirring for 12 hours to obtain a latex. This is referred to as “latex (1HM)”.

(3) Formation of outer layer (third stage polymerization): Preparation of latex 1 An initiator solution obtained by dissolving 6 g of a polymerization initiator (KPS) in 200 ml of ion-exchanged water in the latex (1HM) obtained as described above. And 80 g of styrene 320 g, n-butyl acrylate 64 g, methacrylic acid 16 g, polyfunctional polymerizable monomer (1-1) 48 g, n-octyl-3-mercaptopropionic acid A monomer mixture composed of 12 g of ester was added dropwise over 1 hour. After completion of the dropwise addition, polymerization (third stage polymerization) was performed by heating and stirring for 2 hours, followed by cooling to 28 ° C., a central part composed of latex (1H), an intermediate layer composed of two stages of polymerization, three stages A dispersion of composite resin particles having an outer layer made of polymerization and containing the exemplary compound (19) in the intermediate layer was obtained. This latex is designated as Latex 1.

  The composite resin particles constituting the latex 1 had a mass average particle diameter of 122 nm.

(Preparation of colorant dispersion)
<Preparation of magenta dispersion>
Anionic surfactant (supra) 59.0 g was stirred and dissolved in 1600 ml of ion-exchanged water. While stirring this solution, C.I. I. 420.0 g of Pigment Red 122 was gradually added, and then a magenta dispersion was prepared by dispersing using a stirrer “CLEARMIX” (manufactured by M Technique Co., Ltd.).

  The particle diameter of the colorant particles in the magenta dispersion was measured using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.) and found to be 110 nm.

(Preparation of colored particles a: Preparation of particles by (aggregation / fusion) association)
420.7 g of latex 1 (in terms of solid content), 900 g of ion-exchanged water, and 200 g of the magenta dispersion prepared above were added to a reaction vessel (four-necked flask) equipped with a temperature sensor, a cooling tube, a nitrogen introducing device, and a stirring device. ) And stirred.

  After adjusting the temperature in the container to 30 ° C., 5 mol / liter sodium hydroxide aqueous solution was added to this solution to adjust the pH to 8 to 11.0.

  Next, an aqueous solution obtained by dissolving 12.1 g of magnesium chloride hexahydrate in 1000 ml of ion-exchanged water was added at 30 ° C. over 10 minutes with stirring. After standing for 3 minutes, the temperature increase was started and the system was heated to 90 ° C. over 60 minutes. In this state, the particle size of the associated particles was measured with “Coulter Counter TA-II”. When the volume average particle size reached 4 μm to 7 μm, an aqueous solution in which 40.2 g of sodium chloride was dissolved in 1000 ml of ion-exchanged water. Was added to stop particle growth, and further, fusion was continued by heating and stirring at a liquid temperature of 98 ° C. for 6 hours as an aging treatment to obtain colored particles a.

(Toner preparation)
1% by mass of hydrophobic silica (number average primary particle size = 12 nm, degree of hydrophobicity = 68) and hydrophobic titanium oxide (number average primary particle size = 20 nm, degree of hydrophobicity = 63) Of 0.3% by mass was added and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. The obtained toner had a flow softening point of 120 ° C. and an average particle size of 6 μm.

(Preparation of two-component developer)
A two-component developer was prepared by mixing the electrostatic charge image developing toner prepared above with a ferrite carrier having a volume average particle diameter of 60 μm coated with a silicone binder resin so that the toner concentration was 6%. .

[Image forming apparatus]
As the image forming apparatus, a color digital copying machine having the configuration shown in FIG. 3 of JP-A-2003-173044 was used. As the fixing device, a pressure contact type heat fixing device having the following configuration was used.

  Cylindrical thickness of 1.0 mm with a coating layer (thickness: 120 μm) of PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) on the surface and a heater with an inner diameter of 40 mm and a total width of 310 mm built in the center. The aluminum alloy pipe is a heating roller (upper roller), and the surface has an iron pipe with an inner diameter of 40 mm and a thickness of 2.0 mm, which is similarly composed of sponge-like silicone rubber (Asker C hardness = 48: thickness 2 mm). It has a pressure roller (lower roller). The nip width was 5.8 mm. Using this fixing device, the linear speed of printing was set to 250 mm / second.

  Note that a web-type supply system impregnated with polydiphenyl silicone (having a viscosity of 10 Pa · s at 20 ° C.) is used as a cleaning mechanism for the fixing device, and the fixing temperature is controlled by the surface temperature of the upper roll, 180 ° C. Set temperature.

[Glossiness measurement]
Using the unfixed toner image in which the toner amount of the prepared two-component developer is 0.5 mg / cm ² , the supply of the release agent oil to the heating roller is stopped, and the release agent oil is substantially formed on the surface of the heating roller. In the state where no toner is present, images are formed on the surface side of each electrophotographic image-receiving material at 180 ° C. as a fixing condition and a linear velocity of 30 mm / sec.

  Subsequently, the 60 degree glossiness of the image on each sample was measured using a precision glossiness meter (manufactured by Murakami Color Research Laboratory).

[Evaluation of low-temperature fixability]
In the same manner as described above, using an unfixed toner image with a toner amount of 1.5 mg / cm ² , the heating roller temperature and the pressure roller temperature can be freely set and monitored, and separated from the heating roller. The supply of the mold oil was stopped, and an image was formed on the surface side of each electrophotographic image receiving material in a state where the release agent oil was not substantially present on the surface of the heating roller. That is, the surface temperature of the heating roller was changed stepwise, and the unfixed toner image was fixed using each electrophotographic image receiving material holding the toner image at each surface temperature. At this time, whether or not toner contamination from the heating roller occurred in the blank portion of each sample was visually observed, and a temperature region where no contamination occurred was defined as a non-offset temperature region. Evaluation of the non-offset region was performed as follows based on the non-offset lower limit temperature.

A: Non-offset lower limit temperature is less than 130 ° C. O: Non-offset lower limit temperature is 130 ° C. or more and less than 140 ° C. ×: Non-offset lower limit temperature is 140 ° C. or more [Evaluation of Hot Offset Resistance]
In the same manner as described above, using an unfixed toner image with a toner amount of 1.5 mg / cm ² , the heating roller temperature and the pressure roller temperature can be freely set and monitored, and separated from the heating roller. The supply of the mold oil was stopped, and an image was formed on the surface side of each electrophotographic image receiving material in a state where the release agent oil was not substantially present on the surface of the heating roller. That is, the surface temperature of the heating roller is changed stepwise, and at each surface temperature, the unfixed toner image is fixed using each electrophotographic image-receiving material that holds the toner image, and the occurrence of hot offset is visually observed. The hot offset resistance was evaluated according to the following criteria.

A: No occurrence of hot offset is observed even at 220 ° C. or higher. ○: Hot offset occurs under fixing conditions of 210 ° C. or higher and lower than 220 ° C. ×: Hot offset occurs at a temperature lower than 200 ° C. Results obtained as described above. Is shown in Table 1.

  As is apparent from the results shown in Table 1, the electrophotographic image-receiving material of the present invention has a high glossiness and a low-temperature fixability and hot offset resistance compared to the comparative example. I understand.

Example 2
A printer manufactured by Konica Minolta Business Technology Co., Ltd. modified so that the conveyance speed and the temperature of the fixing device can be changed using the samples 101 to 152 prepared in Example 1 and plain paper (First Class paper manufactured by Konica Minolta Business Technology Co., Ltd.). Images 54 to 106 were output using the magiccolor 2300DL, and the following evaluations were performed on the obtained images. As the toner, a toner for magiccolor 2300DL was used.

(Low temperature fixability)
The fixing temperature was changed under the condition of a conveyance speed of 40 mm / sec, and whether or not toner contamination from the heating roller occurred in the blank portion of each sample was visually observed, and a temperature region where no contamination occurred was defined as a non-offset temperature region. . Evaluation of the non-offset region was performed as follows based on the non-offset lower limit temperature.

A: Non-offset lower limit temperature is less than 130 ° C. O: Non-offset lower limit temperature is 130 ° C. or more and less than 140 ° C. ×: Non-offset lower limit temperature is 140 ° C. or more [Hot offset resistance]
The fixing temperature was changed under the condition of a conveyance speed of 40 mm / sec, the occurrence of hot offset was visually observed, and hot offset resistance was evaluated according to the following criteria.

A: No occurrence of hot offset is observed even at 220 ° C. or higher. ○: Hot offset occurs under fixing conditions of 210 ° C. or higher and lower than 220 ° C. ×: Hot offset occurs at lower than 200 ° C. [Glossiness measurement]
A magenta solid image was printed out under conditions of a conveyance speed of 40 mm / sec and a fixing temperature of 190 ° C., and the 60 ° glossiness of the image on the sample was measured using a precision glossmeter (manufactured by Murakami Color Research Laboratory). .

  Table 2 shows the evaluation results obtained as described above.

  As is clear from the results shown in Table 2, the electrophotographic image-receiving material of the present invention has a high glossiness and a low-temperature fixability and hot offset resistance compared to the comparative example. I understand.

Example 3
A commercially available full-color copying machine “8050” (manufactured by Konica Minolta Business Technology Co., Ltd.) was remodeled and the fixing conditions were changed. As a result of evaluating hot offset resistance and glossiness, it was confirmed that the sample of the present invention showed excellent results.

Claims (6)

An electrophotographic image receiving material having a toner receiving layer on a support, wherein the electrophotographic image receiving material has a heat insulating layer between the support and the toner receiving layer. 2. The electrophotographic image receiving material according to claim 1, wherein the toner receiving layer contains a thermoplastic resin. 3. The electrophotographic image receiving material according to claim 2, wherein the thermoplastic resin is a thermoplastic resin having compatibility with a binder resin of toner. The electrophotographic image receiving material according to claim 1, wherein the heat insulating layer has a void structure. The electrophotographic image-receiving material according to any one of claims 1 to 4, wherein a porosity of the heat insulating layer is 40% or more. The electrophotographic image-receiving material according to claim 1, wherein the heat insulating layer has a thickness of 30 μm or more.