JP2002351121A - Electrophotographic image receiving paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic image receiving paper which has images with excellent gloss and picture quality. SOLUTION: Polypropylene resin layers are directly formed on both surfaces of a paper base, and a toner image receiving layer is formed on the polypropylene resin layer of the top face. The polypropylene resin constituting the polypropylene resin layers has 18 to 50 melt flow rate(MFR) and >=0.890 density.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image-receiving paper which provides an image excellent in glossiness and image quality by a simple method.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic image-receiving paper, a paper in which a polyethylene resin layer is formed directly on the surface of a base paper and an image-receiving layer is further formed thereon is known (for example, Japanese Patent Laid-Open Publication No. HEI 9-284). 2000-10327). Generally, the higher the fixing temperature and the longer the fixing time, the higher the glossiness and image quality of the obtained image. However, although the polyethylene resin layer has excellent adhesiveness to the base paper, it has low heat resistance, so when fixing is performed at a higher temperature, blisters are generated at the interface between the base paper and the polyethylene resin layer, which further increases. However, there is a problem that the glossiness and the image quality of the image are greatly reduced due to the influence on the image in the toner image receiving layer formed in the image forming apparatus.

Hitherto, as a method of preventing blisters, for example, in Japanese Patent Application Laid-Open No. Hei 5-241365, a base paper is coated with a crosslinkable resin such as polyester or polyurethane and then provided with a resin layer cured by radiation. Technology has been proposed. However, although the radiation-curable resin layer has high heat resistance, the production process is complicated, the production equipment is complicated and expensive, and the productivity is further reduced.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electrophotographic image receiving paper having an image excellent in glossiness and image quality by a simple method.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, as a polypropylene resin constituting a polypropylene resin layer provided in direct contact with both sides of the base paper, 18-50 Melt flow rate
The inventors have found that the above problems can be solved by using a polypropylene resin having a (MFR) and a density of 0.890 or more, and have reached the present invention. Japanese Patent Application Laid-Open No. Hei 8-21645 discloses an image bearing material in which a plastic layer is provided on the front and back surfaces of a base paper, and a toner image receiving layer is provided on the plastic layer on the front surface. In addition, this document, in addition to polyethylene, generally refers to polypropylene as a material constituting the plastic layer.However, those specifically disclosed in the examples are only those using polyethylene. Are not specifically disclosed at all. As described above, it is generally considered that polypropylene resin has lower adhesiveness to the base paper than polyethylene resin. This document does not disclose the use of polypropylene having a specific MFR and density for the purpose of improving heat resistance.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. As the base paper used for the electrophotographic image receiving paper of the present invention,
Base paper is used. Pulp that can be used as a raw material for base paper is hardwood bleached kraft pulp (LBK) from the viewpoint of simultaneously improving the surface smoothness, rigidity and dimensional stability (curlability) of base paper to a sufficient level and at the same time.
P) is preferred, but softwood bleached kraft pulp (NBK)
P), hardwood sulphite pulp (LBSP) and the like can also be used. A beater or a refiner can be used to beat the pulp. In the pulp slurry obtained after beating the pulp (hereinafter sometimes referred to as “pulp stock”), various additives, for example, fillers, dry paper strength agents, size Agents, a wet paper strength enhancer, a fixing agent, a pH adjuster, and other agents.

[0007] Examples of the filler include calcium carbonate, clay, kaolin, clay, talc, titanium oxide, diatomaceous earth, barium sulfate, aluminum hydroxide, magnesium hydroxide and the like. 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 wet paper strength enhancers include polyamine polyamide epichlorohydrin, melamine resin,
Examples include urea resins and epoxidized polyamide resins.
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. Examples of other agents include an antifoaming agent, a dye, a slime control agent, a fluorescent whitening agent, and the like. In addition, if necessary, a softening agent and the like can be added. The softening agent is described, for example, in Shin-Paper Processing Handbook (edited by Paper Pharmaceutical Time Co.), pages 554 to 555 (issued in 1980).

[0009] The treatment liquid used for the surface sizing treatment includes:
For example, a water-soluble polymer, a sizing agent, a water-resistant substance, a pigment, a pH adjuster, a dye, an optical brightener, and the like may be included. Examples of the water-soluble polymer include cationic starch, polyvinyl alcohol, carboxy-modified polyvinyl alcohol, carboxymethylcellulose, hydroxyethylcellulose, cellulose sulfate, gelatin, casein, sodium polyacrylate, and styrene.
Maleic anhydride copolymer sodium salt, sodium polystyrene sulfonate and the like can be mentioned.

As the sizing agent, for example, petroleum resin emulsion, ammonium salt of styrene-maleic anhydride copolymer alkyl ester, rosin, higher fatty acid salt,
Examples thereof include alkyl ketene dimer (AKD) and epoxidized fatty acid amide. As the water-resistant substance, for example,
Latex emulsions such as styrene-butadiene copolymer, ethylene-vinyl acetate copolymer, polyethylene, vinylidene chloride copolymer, and polyamidepolyamine epichlorohydrin.

Examples of the pigment include calcium carbonate, clay, kaolin, talc, barium sulfate, titanium oxide and the like. Examples of the base paper material include synthetic pulp paper, mixed paper of natural pulp and synthetic pulp, and various kinds of laminated paper, in addition to the above-described natural pulp paper. The thickness of the base paper, that is, the base paper is usually 3
Suitably, it is 0 to 500 μm, preferably 50 to 300 μm, particularly preferably 100 to 200 μm. The base paper as described above has a ratio (Ea / Eb) between the Young's modulus in the longitudinal direction (Ea) and the Young's modulus in the transverse direction (Eb) in order to improve the rigidity and dimensional stability (curlability) of the electrophotographic image-receiving paper.
) Is preferably in the range of 1.5 to 2.0. Ea
If the / Eb value is less than 1.5 or more than 2.0, the rigidity and curl of the electrophotographic image-receiving paper are liable to be deteriorated, and the running property at the time of conveyance is disturbed. .

In general, it has been found that the "strain" of paper differs based on the difference in the mode of beating, and the elastic force (rate) of the paper formed after beating is determined by the degree of "strain" of the paper. Can be used as an important factor representing In particular, the elastic modulus of paper is measured by using the relationship between the dynamic elastic modulus and density, which indicate the physical properties of the viscoelastic material of paper, and measuring the speed of sound propagating through the paper using an ultrasonic vibration element. Can be obtained from the following equation. E = ρc ² (1-ν ² ) [E: dynamic elastic modulus, ρ: density, c: sound velocity in paper, ν: Poisson's ratio]

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

The basis weight of the base paper is, for example, 50 to 250 g /
m ² , preferably in the range of 100 to 180 g / m ² . Specific examples of the base paper include high-quality paper and, for example, "Basics of Photographic Engineering-Silver halide photography-" edited by The Photographic Society of Japan, published by Corona Co., Ltd. (1979) (223)-(24)
0) Paper described on the page is mentioned as a preferable example. A plurality of base papers may be used. In addition, on both sides or one side of the base paper, for the purpose of improving the adhesiveness with a polypropylene resin layer described later provided on the base paper, an activity such as a corona discharge treatment, a flame treatment, a glow discharge treatment, or a plasma treatment is performed. It is preferable to carry out a chemical treatment.

The polypropylene resin constituting the polypropylene resin layer provided directly on both sides of the polypropylene resin layer base paper has a melt flow rate (M
FR) is suitably 18 or more, preferably 25 or more, and particularly preferably 35 or more. MFR is 1
If it is less than 8, the adhesiveness to the base paper is low, so that it cannot withstand the foaming pressure due to moisture in the base paper at the time of thermal fixing, causing blistering and surface defects. On the other hand, the upper limit of the MFR is not particularly limited, but is suitably 50, preferably 48, and particularly preferably about 45. If it exceeds 50,
When the polypropylene resin layers are bonded by lamination molding, the film width is likely to fluctuate, the linearity of the edge is reduced, and neck-in is likely to occur. Further, by providing a polypropylene resin layer on both sides of the base paper, moisture absorption can be prevented, so that elongation on both sides of the electrophotographic image receiving paper is uniformly suppressed, and cracking and curling can be prevented.

The density of the polypropylene resin used in the polypropylene resin layer is 0.890 or more, preferably 0.900 or more, and more preferably 0.905 or more. If the density is less than 0.890, stains and blisters are likely to occur on the fixing roll, which is not preferable.
On the other hand, the density can usually be used up to 0.910.
The thickness of the polypropylene resin layer is usually 5 to 50 μm,
Preferably, the thickness is 10 to 30 μm.
The polypropylene resin layer provided in direct contact with the surface of the base paper (toner image receiving layer side) is preferably a mirror surface (glossy surface). On the other hand, it is appropriate that the polypropylene resin layer provided on the back surface of the base paper has a matte surface. For the matte surface, for example, the arithmetic average roughness (Ra) is 2
It is preferably at most 0 μm, more preferably at most 10 μm, particularly preferably at most 8 μm. In the roughness measurement test, Ra is suitably, for example, 1 to 20 μm, preferably 5 to 10 μm.

The polypropylene resin layer is preferably provided directly on the base paper by laminating the surface of the base paper by melt extrusion. The polypropylene resin layer may be laminated in multiple layers on each side of the base paper. In this case, a plurality of layers of the same or different polypropylene resins, for example, two or more laminated layers can be formed by co-melt extrusion. The polypropylene resin layer does not substantially contain a pigment or a filler. Even if included, at most, for example, up to 15% by mass is appropriate based on the mass of the polypropylene resin layer. If the pigment or the like is contained in this amount or more, the electrophotographic image receiving paper after receiving the image is easily stretched due to moisture absorption,
Stress is generated between the image receiving layer and the toner layer, causing curl and cracking of the toner layer. Therefore, pigments and the like can be used as long as such a problem does not occur. However, it is particularly preferable that no pigment or the like is contained at all.

[0018] In the toner image-receiving layer present invention, on a polypropylene resin layer provided on the surface of the base paper, the toner image-receiving layer is provided. The toner image receiving layer used in the present invention is (static)
It has a function of receiving toner for forming an image from a developing drum or an intermediate transfer member by electricity, pressure, or the like, and fixing the toner by heat, pressure, or the like in a fixing process. The toner image-receiving layer used in the present invention can contain various additives together with the thermoplastic resin as long as it does not affect the function as the toner image-receiving layer. It is appropriate that the thickness of the toner image receiving layer is 径 or more, preferably 1 to 3 times the particle diameter of the toner used. As the toner image receiving layer, those having a thickness disclosed in JP-A-5-216322 and JP-A-7-301939 are preferable. In particular,
The thickness is, for example, 2 to 30 μm, preferably 5 to 15 μm.
μm is appropriate.

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 of the items. (1) Tg (glass transition temperature) of the toner image receiving layer is 30 ° C.
Above, Tg of toner + 20 ° C or less. (2) T1 / 2 (1/2 method softening point) of the toner image receiving layer is
60-200 ° C, preferably 80-170 ° C. Here, the 法 method softening point is determined by using a specific apparatus, under a specific condition and applying a predetermined extrusion load, at an initial set temperature (for example, 50 ° C.) and a residual heat time, for example, 300 seconds. Later, the temperature is evaluated at a temperature that is half the difference between the piston strokes at the start and end of the outflow at each temperature when the temperature is raised at a predetermined constant speed. (3) Tfb (outflow start temperature) of the toner image receiving layer is 40
200 ° C., preferably Tfb of the toner image receiving layer is equal to or lower than Tfb of the toner + 50 ° C. (4) The temperature at which the viscosity of the toner image receiving layer becomes 1 × 10 ⁵ CP is 40 ° C. or higher, which is 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.

(6) The loss tangent (G ″ / G ′), which is the ratio of the loss elastic modulus (G ″) at the fixing temperature of the toner image receiving layer to 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 storage elastic modulus (G ″) at the fixing temperature of the toner. (8) On the image receiving layer of the fused toner The inclination angle is 50 degrees or less,
Especially below 40 degrees. Further, as the toner image receiving layer, JP-A-2788358, JP-A-7-248637, and 8-305067
And those satisfying the physical properties disclosed in JP-A-10-239889 and the like.

The physical properties (1) can be measured by a differential scanning calorimeter (DSC). (2)-
The physical properties (4) can be measured, for example, using a flow tester CFT-500 or 500D manufactured by Shimadzu Corporation. The physical properties (5) to (7) can be measured using a rotary rheometer (for example, a dynamic analyzer RADII manufactured by Rheometric Corporation). The physical properties of (8) can be measured by a method disclosed in JP-A-8-334916, using a contact angle measuring device manufactured by Kyowa Interface Chemical Co., Ltd.

The thermoplastic resin used in the toner image-receiving layer of the present invention may be any thermoplastic resin which can be deformed at the fixing temperature to receive the toner. Preferably, the thermoplastic resin used in the toner image receiving layer is a resin of the same type as the resin used as the binder of the toner. In many cases, the toner includes a polyester resin, a styrene-acrylate copolymer, a styrene-methacrylate copolymer, and the like. In that case, the thermoplastic resin used in the toner image receiving layer of the present invention is used. Also, it is preferable to use a thermoplastic resin such as a polyester resin, a styrene-acrylate copolymer, and a styrene-methacrylate copolymer.

As such a thermoplastic resin, for example, the following thermoplastic resins can be exemplified. (A) Polyolefin resins such as polyethylene resins and polypropylene resins, copolymer resins of olefins such as ethylene and propylene with other vinyl monomers, and acrylic resins. (B) having an ester bond terephthalic acid, isophthalic acid, maleic acid, fumaric acid,
Dicarboxylic acid components such as phthalic acid, adipic acid, sebacic acid, azelaic acid, abietic acid, succinic acid, trimellitic acid, and pyromellitic acid (these dicarboxylic acid components are substituted with sulfonic acid groups, carboxyl groups, etc. And ethylene glycol, diethylene glycol,
Propylene glycol, bisphenol A, a diether derivative of bisphenol A (for example, bisphenol A
And alcohol components such as bisphenol S, 2-ethylcyclohexyl dimethanol, neopentyl glycol, cyclohexyl dimethanol, and glycerin (such as hydroxyl groups in these alcohol components). May be substituted) and a polyester resin obtained by condensation with

Polyacrylate resins such as polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate or the like, polymethacrylate resins, polycarbonate resins, polyvinyl acetate resins, styrene acrylate resins, and styrene-methacrylate esters Polymer resin, vinyl toluene acrylate resin, etc. Specifically, JP-A-59-1013
No. 95, No. 63-7971, No. 63-7972, No. 63-7973, and No. 60-294882. Also, commercially available products include Byron 290, Byron 200, and Byron 28 manufactured by Toyobo.
0, Byron 300, Byron 103, Byron GK-
140, Byron GK-130, Kafu-made Tuffton NE
-382, Tufton U-5, ATR-2009, ATR
-2010, Unitika ELIETEL UE3500, U
E3210, XA-8153, Nippon Synthetic Chemical's Polyester TP-220, R-188 and the like can be used.

(C) Polyurethane resin and the like. (D) Polyamide resin, urea resin and the like. (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) Polyol resins such as polyvinyl butyral, and cellulose resins such as ethyl cellulose resin and cellulose acetate resin. (H) Polycaprolactone resin, styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin and the like. The thermoplastic resins may be used alone or as a mixture of these thermoplastic resins. Such a thermoplastic resin is usually 20% by mass or more, preferably 30 to 100% by mass, based on the mass of the toner image receiving layer.
Suitably it is blended.

Examples of the thermoplastic resin used for the toner image receiving layer include Japanese Patent Publication No. 5-127413 and 8-1943.
No. 94, No. 8-334915, No. 8-334916
And those satisfying the physical properties etc. disclosed in JP-A Nos. 9-171265 and 10-221877 are preferably used. As the thermoplastic resin used in the toner image-receiving layer of the present invention, those capable of satisfying the above-described physical properties of the image-receiving layer in a state where the image-receiving layer is formed are preferable. More preferably,
As the resin alone, those satisfying the above-mentioned preferable physical properties for the toner image receiving layer can be used. Further, two or more resins having different physical properties described above can be used in combination.

As the thermoplastic resin used for the toner image receiving layer, those having a molecular weight larger than that of the thermoplastic resin used for the toner are preferably used. However, the above-mentioned molecular weight relationship is not always preferable depending on the relationship between the thermodynamic properties of the toner resin and the thermoplastic resin used for the toner image receiving layer. For example, when the softening temperature of the thermoplastic resin used in the toner image receiving layer is higher than that of the toner resin, it may be preferable that the molecular weight is equal or the thermoplastic resin of the toner image receiving layer is smaller. As the thermoplastic resin used for the toner image receiving layer, it is also preferable to use a mixture of resins having the same composition and different average molecular weights. The relationship with the molecular weight of the thermoplastic resin used for the toner is preferably the relationship disclosed in JP-A-8-334915. The molecular weight distribution of the thermoplastic resin used for the toner image receiving layer is preferably wider than the molecular weight distribution of the thermoplastic resin used for the toner.

The thermoplastic resin used for the toner image receiving layer may be water-soluble. The composition, bonding structure, molecular structure, molecular weight, molecular weight distribution, form, and the like of the water-soluble thermoplastic resin are not particularly limited as long as the resin is water-soluble. In order to make the thermoplastic resin water-soluble, for example, it is necessary that the thermoplastic resin has a water-solubilizing group. Examples of the water-solubilizing group include, for example, a hydroxyl group, a carboxylic acid group, and an amino group. Groups, amide groups, ether groups and the like. Examples of the water-soluble thermoplastic resin include Research Disclosure No. 17,643, page 26, 18,716.
No. 651, pages 873-874 of 307,105 and pages (71)-(75) of JP-A-64-13546. Specifically, as the water-soluble thermoplastic resin, for example, vinylpyrrolidone-vinyl acetate copolymer, styrene-vinylpyrrolidone copolymer, styrene-maleic anhydride copolymer, water-soluble polyester, water-soluble polyurethane, Water-soluble nylon, water-soluble epoxy resin and the like can be used.

The toner image-receiving layer can be prepared by coating a non-water-soluble thermoplastic resin on a polypropylene resin layer with, for example, an aqueous dispersion. Aqueous dispersions include acrylic resin emulsions, polyvinyl acetate emulsions, SBR (styrene
Butadiene / rubber) emulsions, polyester resin emulsions, polystyrene resin emulsions, urethane resin emulsions and the like can be appropriately selected, and two or more kinds can be used in combination. In the case of gelatin, it can be selected from lime-processed gelatin, acid-processed gelatin, and so-called demineralized gelatin in which the content of calcium and the like is reduced depending on the purpose.

When the binder of the toner is a polyester resin, the resin of the toner image receiving layer is preferably a polyester resin. As a commercially available polyester resin,
For example, Toyobo Byron 290, Byron 200,
Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130, Tufton NE-382, Tufton U-5, ATR-20 manufactured by Kao
09, ATR-2010, Unitika ELITEL UE
3500, UE3210, XA-8153, Nippon Gohsei Chemical's Polyester TP-220, R-188, and the like. As the acrylic resin, commercially available trade names such as Mitsubishi Rayon Co., Ltd. SE-
5102, SE-5377, SE-5649, SE-5
466, SE-5482, HR-169, 124, HR
-1127, HR-116, HR-113, HR-14
8, HR-131, HR-470, HR-634, HR
-606, HR-607, LR-1065, 574, 1
43, 396, 637, 162, 469, 216, BR
-50, BR-52,

BR-60, BR-64, BR-73, B
R-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-108, BR-112, BR-1
13, BR-115, BR-116, BR-117, Sekisui Chemical Co., Ltd. S-LEC P SE-0020, SE-0
040, SE-0070, SE-0100, SE-10
10, SE-1035, Sanyo Chemical Hymer ST9
5, ST120, FM601 manufactured by Mitsui Chemicals, or the like can be used. Commercially available polyester emulsions include, for example, Toyobo Vironal MD-1250 and MD-19.
30, Plus Coat Z-446, Z-46
5, RZ-96, Nippon Nippon Ink's ES-611, ES-
670, Takamatsu Yushi Pesresin A-160P, A-21
0, A-515GB, A-620 and the like. The film forming temperature of the thermoplastic resin is preferably room temperature or higher for storage before printing, and is preferably 100 ° C. or lower for fixing toner particles.

In the toner image receiving layer used in the present invention, in addition to the thermoplastic resin, various additives can be oriented for the purpose of improving the thermodynamic properties of the toner image receiving layer. Examples of such additives include a plasticizer, a slipping agent or a release agent, a filler, a crosslinking agent, an emulsion, and a dispersion. As the plasticizer, a known plasticizer for a resin can be used without any particular limitation. The plasticizer has a function of adjusting flow and softening of the toner image receiving layer by heat and / or pressure when fixing the toner. Examples of plasticizers include “Chemical Handbook” (edited by The Chemical Society of Japan, Maruzen),
"Plasticizers-Theory and Applications-" (edited by Koichi Murai, Koshobo), "Research on Plasticizers", "Research on Plasticizers" (edited by the Society of Polymer Chemistry), "Handbook Rubber and Plastic Compounding Chemicals" ( Rubber Digest Co., Ltd.) and the like.

Some plasticizers are described as high-boiling organic solvents, hot solvents and the like.
-83154, 59-178451, 59-1
No. 78453, No. 59-178454, No. 59-17
No. 8455, No. 59-178457, No. 62-174
No. 754, No. 62-245253, No. 61-2094
No. 44, No. 61-200538, No. 62-8145
No. 62-9348, No. 62-30247, No. 6
2-136646, 62-174754, 62
-245253, 61-209444, 61-
No. 200538, No. 62-8145, No. 62-934
No. 8, No. 62-30247, No. 62-136646
(For example, phthalates, phosphates, fatty acid esters, abietic esters, adipic esters, sebacic esters) described in JP-A-2-235694 and JP-A-2-235694. , Azelaic acid esters,

Benzoic acid esters, butyric acid esters, epoxidized fatty acid esters, glycolic acid esters,
Propionates, trimellitates,
Citric acid esters, sulfonic acid esters, carboxylic acid esters, succinic acid esters, maleic acid esters, fumaric acid esters, phthalic acid esters, stearic acid esters, etc.), amides (for example, fatty acid amides) , Sulfoamides, etc.), ethers, alcohols, lactones, polyethyleneoxys and the like. The plasticizer can be used by mixing with the resin.

As the plasticizer, a polymer having a relatively low molecular weight can be used. In this case, the molecular weight is preferably lower than the molecular weight of the binder resin to be plasticized, and suitably the molecular weight is 15,000 or less, preferably 5000 or less. In the case of a polymer plasticizer, the polymer is preferably the same type of polymer as the binder resin to be plasticized. For example, a low molecular weight polyester is preferable for plasticizing a polyester resin. Further, oligomers can also be used as plasticizers. Commercially available products other than the compounds listed above include, for example, Asahi Denka Kogyo Adecizer PN-170 and PN-170.
1430 and C.I. P. HALL PARAPLEX
-G-25, G-30, G-40, Rika Hercules products ester gum 8L-JA, ester R-95, pentalin 4851, FK115, 4820, 830, Luizol 28-JA, picolatics A75, picotex LC, crystal Rex 3085 and the like.

The plasticizer is a stress or strain generated when the toner particles are embedded in the toner image receiving layer (physical strain such as elastic force and viscosity, strain due to material balance of molecules, binder main chain, pendant portion, etc.). Can be used arbitrarily to mitigate the In the toner image receiving layer, the plasticizer may be in a micro-dispersed state, may be in a micro-phase-separated state in a sea-island state, or may be in a state of being sufficiently mixed and dissolved with other components such as a binder. The plasticizer is, for example, 0.001 to 9 based on the mass of the toner image receiving layer.
It is preferable to mix 0 mass%, preferably 0.1 to 60 mass%, particularly preferably 1 to 40 mass%. The plasticizer is used to adjust slipperiness (improve transportability due to reduced frictional force), improve fixing portion offset (peeling of toner or layer to the fixing portion), adjust curl balance, and adjust charging (toner electrostatic image). May be used for such purposes.

The slipping agent or release agent which can be optionally used in the present invention is added for the purpose of preventing the electrophotographic image-receiving paper of the present invention from adhering to the fixing heating member during fixing. In particular, the 180 ° peel strength of the toner image receiving layer at the fixing temperature with the fixing member is suitably 0.1 N / 25 mm or less, more preferably 0.041 N / 25 mm or less. The 180-degree peel strength can be measured using the surface material of the fixing member according to the method described in JIS K6887. Examples of the slipping agent or release agent used in the electrophotographic image-receiving paper of the present invention include higher alkyl sodium sulfate, higher fatty acid higher alcohol ester, carbowax, higher alkyl phosphate ester, silicone compound, modified silicone, curable Silicone and the like are included. Further, polyolefin wax, fluorine-based oil, fluorine-based wax, carnauba wax, microcrystalline wax, and silane compound are also preferably used.

As for the slipping agents or releasing agents which can be used, US Pat. Nos. 2,882,157 and 3,121,060.
No. 3850640, French Patent 2180465
Nos., British Patent Nos. 955061, 1143118, 1263722, 1270578, 13205
No. 64, No. 1320757, No. 2588765, No. 2739891, No. 3018178, No. 30425
No. 22, No. 3080317, No. 308087, No. 312060, No. 3222178, No. 32959
No. 79, No. 3489567, No. 3516832, No. 3658573, No. 3679411, No. 38705
No. 21, JP-A-49-5017 and JP-A-51-50.
No. 141623, No. 54-159221, No. 56-8
No. 1841, and Research Disclosure 13969.

The amount of the slipping agent or release agent used is 5 to 500.
mg / m ^2, is preferably a suitably be 10 to 200 mg / m ^2. A preferable amount of the slipping agent or the release agent in the case of so-called oilless fixing without using oil for preventing offset to the fixing member in the fixing portion is, for example, 30 to 3000 mg / m ² , preferably 100 ~
1500 mg / m ² . Since a wax-based slip agent or release agent is hardly dissolved in an organic solvent, it is preferable to prepare an aqueous dispersion, prepare a dispersion with a thermoplastic resin solution, and apply the dispersion. In this case, the wax-based slip agent or release agent is present in the thermoplastic resin in the form of fine particles. In this case, the amount of the slip agent used is 5 to 10,000 mg / m ² , preferably 50 to 5000 mg / m ² . Examples of the slipping agent or the releasing agent include a silicon compound, a fluorine compound, and a wax.

As the slipping agent or the release agent, compounds described in Kokai Shobo “Revised Properties and Application of Wax” and Silicone Handbook published by Nikkan Kogyo Shimbun can be generally used. No. 59-38581, No. 4-32380, No. 2838498, No. 29
No. 49558, JP-A-50-117433, and JP-A-52-117433.
No. 52640, No. 57-148755, No. 61-62
Nos. 056, 61-62057, 61-11876
No. 0, JP-A-2-42451, JP-A-3-41465,
4-212175, 4-214570, 4-
No. 263267, No. 5-34966, No. 5-1195
No. 14, No. 6-59502, No. 6-161150,
6-175396, 6-219040,

Nos. 6-230600 and 6-29509
No. 3, 7-36210, 7-43940, 7
-56387, 7-56390, 7-6433
5, No. 7-199681, No. 7-223362,
Nos. 7-287413, 8-184992, 8-
No. 227180, No. 8-248671, No. 8-248
No. 799, No. 8-248801, No. 8-278663
Nos. 9-152739, 9-160278, 9-185181, 9-319139, and 9-3
No. 19143, No. 10-20549, No. 10-488
No. 89, No. 10-198069, No. 10-20711
No. 6, No. 11-2917, No. 11-44969, No. 11-65156, No. 11-73049, No. 11-
Silicon compounds, fluorine compounds, waxes and the like used in the toners described in the respective publications of 194542 are preferably used. These compounds may be used in combination of two or more.

Specifically, as the silicon-based compound,
For example, as a silicone oil, an unmodified silicone oil (specifically, dimethylsiloxane oil, methyl hydrogen silicone oil, phenylmethyl silicone oil, KF-9 manufactured by Shin-Etsu Chemical as a commercial product)
6, 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, Dow Corning Toray Silicone S
H200, SH203, SH490, SH510, SH
550, SH710, SH704, SH705, SH7
028A, SH7036, SM7060, SM700
1, SM7706, SH7036, SH8710, SH
1107 and SH8627.

Examples of the fluorine compound include a fluorine oil (a commercially available product, Daifoil # 1 manufactured by Daikin Industries,
# 3, # 10, # 20, # 50, # 100, Unidyne TG-440, TG-452, TG-490, TG-5
60, TG-561, TG-590, TG-652, T
G-670U, TG-991, TG-999, TG-3
010, TG-3020, TG-3510, TK-100, MF-110, MF-12 manufactured by Tochem Products
0, MF-130, MF-160, MF-160E, Surflon S-111, S-112, S-11 manufactured by Asahi Glass
3, S-121, S-131, S-132, S-14
1, S-145, FC-430 manufactured by Mitsui Fluorochemicals,
FC-431, etc.), fluoro rubber (Toray
Dow Corning Silicone LS63U, etc.), Fluorine-modified resin (Nippon Yushi Modiper F20 as a commercial product)
0, F220, F600, F2020, F3035, Dialomer FF203, FF204 manufactured by Dainichi Seika.

As the wax, for example, paraffin wax as a petroleum wax (a commercially available paraffin wax 155, 150, 140, 135, 1
30, 125, 120, 115, HNP-3, HNP-
5, HNP-9, HNP-10, HNP-11, HNP
-12, HNP-14G, SP-0160, SP-01
45, SP-1040, SP-1035, SP-304
0, SP-3035, NPS-8070, NPS-L-
70, OX-2151, OX-2251, EMUSTA
R-0384, EMUSTAR-0136, Cellosol 686, 428, 651-A, A, H-80 manufactured by Chukyo Yushi
3, B-460, E-172, 866, K-133, Hydrin D-337, E-139, Nippon Mitsubishi Oil 12
5 ° paraffin, 125 ° FD, 130 ° paraffin,
135 ° paraffin, 135 ° H, 140 ° paraffin, 140 ° N, 145 ° paraffin, paraffin wax M) and the like. As a slipping agent or a release agent optionally added to the toner image receiving layer of the present invention,
These derivatives, oxides, purified products, and mixtures can also be used. Further, these may have a reactive substituent. The slipping agent or release agent used in the present invention,
For example, 0.1 to 1 based on the mass of the toner image receiving layer.
0 mass%, preferably 0.3 to 8.0 mass%, particularly preferably 0.5 to 5.0 mass%.

As the organic or inorganic filler arbitrarily added to the toner image receiving layer of the present invention, those known as a reinforcing agent for a binder resin, a filler and a reinforcing material can be used. Fillers can be selected with reference to Handbook of Rubber / Plastic Compounding Chemicals (Rubber Digest), New Edition Plastics Compounding Fundamentals and Applications (Taiseisha), Filler Handbook (Taiseisha), etc. it can. Various inorganic fillers (or pigments) can be used as the filler. As the inorganic pigment, for example, silica, alumina, titanium dioxide, zinc oxide, zirconium oxide, mica-like iron oxide, lead white, lead oxide, cobalt oxide, strontium chromate, molybdenum-based pigment, smectite, magnesium oxide, calcium oxide, carbonate Calcium, mullite and the like.
As the filler, silica and alumina are particularly preferable. Two or more fillers may be used in combination. As the filler, those having a small particle size are preferable. When the particle size is large, the surface of the toner image receiving layer is easily roughened.

The silica includes spherical silica and amorphous silica. 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 trimethylsilyl groups or silicone. As silica, colloidal silica is preferred. The average particle size of the silica is, for example, 4 to 120 nm, preferably 4 to 120 nm.
Suitably, it is ９０90 nm. The silica is preferably porous. The average pore size of the porous silica is 5
0 to 500 nm is preferred. The average pore volume per mass of the porous silica is preferably, for example, 0.5 to 3 ml / g.

Alumina includes anhydrous alumina and alumina hydrate. As the crystal form of anhydrous alumina, α,
β, γ, δ, ζ, η, θ, κ, ρ or χ can be used. Alumina hydrate is preferred over anhydrous alumina. Monohydrate or trihydrate can be used as the alumina hydrate. Monohydrates include pseudoboehmite, boehmite and diaspore. In trihydrate,
Includes gibbsite and bayerite. The average particle size of alumina is, for example, 4 to 300 nm, preferably 4 to 300 nm.
Suitably, it is 200 nm. Alumina is preferably porous. The average pore diameter of the porous alumina is suitably, for example, 50 to 500 nm. The average pore volume per mass of the porous alumina is preferably, for example, 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 alkali aluminate is hydrolyzed. Anhydrous alumina can be obtained by dehydrating alumina hydrate by heating. The filler is preferably 5 to 2000% by mass based on the dry mass of the binder of the layer to be added.

The toner image-receiving layer of the present invention preferably contains a charge control agent in order to adjust the transfer and adhesion of the toner and to prevent the toner image-receiving layer from being charged. As the charge control agent, various charge control agents known in the art can be used. Examples of such a charge controlling agent include, for example, cationic surfactants, anionic surfactants, amphoteric surfactants, surfactants such as nonionic surfactants, polymer electrolytes, and conductive metal oxides. Things can be used. For example, quaternary ammonium salts, polyamine derivatives, cation-modified polymethyl methacrylate,
Cationic antistatic agents such as cation-modified polystyrene,
Examples include, but are not limited to, anionic antistatic agents such as alkyl phosphates and anionic polymers, and nonionic antistatic agents such as fatty acid esters and polyethylene oxide.

When the toner has a negative charge, the toner image
Examples of the charge control agent to be blended in the layer include, for example, cationic
And nonionic are preferred. Examples of the conductive metal oxide include ZnO and TiO.
_Two , SnO_Two, Al_TwoO _Three In_TwoO_Three , SiO_Two, MgO
 , BaO, MoO_ThreeAnd the like. these
The conductive metal oxide may be used alone, and these
It may be used as a composite oxide. In addition, metal oxides
A seed element may be further contained.
And TiO such as Al and In_Two For Nb, Ta, etc.
SnO_TwoContains Sb, Nb, halogen elements, etc.
Yes (doping) is possible.

The toner image receiving layer used in the present invention is 1 ×
10⁶ ~ 1 × 10¹⁵Range (25 ° C, 65% RH conditions)
) Is preferable. 1x1
0⁶If it is less than Ω, the toner is transferred to the toner image receiving layer.
When the toner amount is insufficient, the resulting toner image
The degree tends to be low. On the other hand, the surface electric resistance is 1 × 10 ¹⁵
If it exceeds Ω, an unnecessary charge is generated during transfer
Toner is not sufficiently transferred, the image density is low,
Static electricity is applied to the photo paper when handling it.
Easy to wear, misfeed, double feed, discharge mark during copying
And toner transfer drop easily occur.
Absent.

The optimum surface electric resistance of the transparent toner image receiving layer ranges from 10 ¹⁰ to 10 ¹³ Ω / cm ² , preferably 5 × 10 ¹³ Ω / cm ² .
10 ¹⁰ a ^{~5 × 10 12 Ω / cm 2} , the amount of the antistatic agent, the values of surface electrical resistivity may be an amount as falling within this range. The surface electric resistance of the surface opposite to the toner image receiving layer with respect to the support is 5 × 10 ^{8 to} 3.2 × 10 ¹⁰ Ω /.
cm ² , preferably 1 × 10 ⁹ to 1 × 10 ¹⁰ Ω / cm ²
Is suitable. Measurement of surface electric resistance is based on JIS K6
In accordance with 911, the sample was conditioned for 8 hours or more in an environment of a temperature of 20 ° C. and a humidity of 65%, and in the same environment, a current was supplied by using R8340 manufactured by Advantest Co. under an applied voltage of 100 V. It is obtained by measuring after one minute has passed.

The toner image-receiving layer used in the electrophotographic image-receiving paper of the present invention has a purpose of improving image quality, particularly whiteness.
A fluorescent whitening agent, a white pigment, a colored pigment, a dye, or the like can be used. The optical brightener has absorption in the near ultraviolet region,
A compound that emits fluorescence at a wavelength of from 00 to 500 nm, and various types of known optical brighteners can be used without particular limitation. Examples of the optical brightener include K.K. "The Chemistry of Syntheti, edited by Ween Rataraman
Compounds described in c Dyes ", Vol. V, Chapter 8. Specific examples include stilbene compounds, coumarin compounds, biphenyl compounds, benzoxazoline compounds, naphthalimide compounds, and pyrazolines. Compounds, carbostyril compounds, etc. Examples of such compounds are White Flufer PSN, PHR, HCS, PCS, B, Ciba-, manufactured by Sumitomo Chemical.
And UVITEX-OB manufactured by Geigy Corporation.

As the white pigment, the inorganic pigments (titanium oxide, calcium carbonate, etc.) described in the section of the filler can be used. Examples of colored pigments include various pigments and azo pigments described in JP-A-63-44653 and the like (azo lake; carmine 6B, red 2B, insoluble azo; monoazo yellow, disazo yellow, pyrazolo orange, vulcan orange, condensed azo series) Chromophtaleilro, chromophtal red), polycyclic pigments (phthalocyanine-based; copper phthalocyanine blue, copper phthalocyanine green, cyoxazine-based; dioxazine violet, isoindolinone-based; isoindolinone yellow, sulene-based; perylene,
Perinone, flavanthrone, thioindigo, lake pigment (malachite green, rhodamine B, rhodamine G,
Victoria Blue B) and inorganic pigments (oxide, titanium dioxide, red iron oxide, sulfate; precipitated barium sulfate, carbonate;
Precipitated calcium carbonate, silicate; hydrous silicate, anhydrous silicate, metal powder; aluminum powder, bronze powder, zinc dust, carbon black, graphite, navy blue and the like.

As the dye, various known dyes can be used. Examples of the oil-soluble dye include anthraquinone compounds and azo compounds. Specific examples of the water-insoluble dye include C.I. I. Vat Violet 1,
C. I. Vat Violet 2, C.I. I. Vat Violet 9, C.I. I. Vat Violet 13,
C. 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, C.I. I. Disperse 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 2
1, C.I. I. Solvent Violet 27, C.I. I.
Solvent Blue 11, C.I. I. Solvent Blue 1
2, C.I. I. Solvent Blue 25, C.I. I. There are oil-soluble dyes such as Solvent Blue 55.

Colored couplers used in silver halide photography can also be preferably used. The toner image receiving layer used in the electrophotographic image receiving paper of the present invention preferably has high whiteness. CIE 1976 (L
In the * a * b *) color space, the L * value is preferably 80 or more, more preferably 85 or more, and still more preferably 90 or more. Further, it is preferable that the white color is 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,
More preferably, it is 5 or less. Further, the toner image receiving layer of the present invention preferably has high gloss. The gloss is preferably 45 degrees or more, more preferably 75 or more, more preferably 90 or more in the entire region from white without toner to black with the maximum density.
That is all. However, the glossiness is preferably 110 or less. If it exceeds 110, it becomes metallic luster, which is not preferable as image quality.

The glossiness can be measured based on JIS Z8741. Further, it is preferable that the toner image receiving layer used in the present invention has high smoothness. As the smoothness, the arithmetic average roughness (Ra) is preferably 3 μm or less, more preferably 1 μm or less, and still more preferably, in the entire region from white without toner to black with maximum density.
It is 0.5 μm or less. Arithmetic average roughness is JIS B
0601, B0651, and B0652.

In the toner image receiving layer used in the present invention, various antioxidants, antioxidants, antioxidants, ozone deterioration, etc. are used to improve the stability of the output image and the stability of the image receiving layer itself. Inhibitors, ultraviolet absorbers, light stabilizers, preservatives, fungicides and the like may be added. Antioxidants include, for example, chroman compounds, coumaran compounds, phenol compounds (eg, hindered phenols), hydroquinone derivatives, hindered amine derivatives, and spiroindane compounds. Further, as an antioxidant, JP-A-61
Various antioxidants described in JP-A-159644 can be used. Examples of the anti-aging agent include, for example, “Handbook of Rubber and Plastic Compounding Revision 2nd Edition” (1993, Rubber Digest Co., Ltd.), pp. 76-1.
21.

Examples of the ultraviolet absorber include a benzotriazole compound (described in US Pat. No. 3,533,794) and a 4-thiazolidone compound (US Pat. No. 33526).
No. 81), benzophenone compounds (Japanese Unexamined Patent Publication No.
No. 6-2784) and an ultraviolet absorbing polymer (described in JP-A-62-260152). Examples of the metal complex include, for example, U.S. Pat. Nos. 4,241,155, 4,245,018 and 4,254,195, JP-A-61-88256, and JP-A-62-174741.
No. 63-199248, JP-A-1-75568
And No. 1-74272. Also, "Handbook of Rubber and Plastic Compounding Chemicals Revised Second Edition" (1993, Rubber Digest) p122
To 137 are also preferably used.

Further, in the toner image receiving layer used in the present invention, various known additives as photographic additives can be used. For example, as a photographic additive, Research Disclosure Magazine (hereinafter abbreviated as RD) No. 17
643 (December 1978) and No. 18716 (19
November 1979) and No. 307105 (January 1989)
(January), and the relevant sections are summarized below. Type of additive RD17643 RD18716 RD30710 Brightener page 24 page 648 right column page 868 2. Stabilizer page 24-25 page 649 right column pages 868-870 3. 3. Light absorber page 25-26 page 649 right column page 873 UV absorber 4. 4. Dye image stabilizer page 25 page 650 right column page 872 5. Hardener page 26 page 651 left column pages 874-875 Binder page 26 page 651 left column pages 873 to 874 7. 7. Plasticizer / lubricant page 27 page 650 right column page 876 8. Coating aid page 26-page 27 650 page right column page 875-876 Surfactant Antistatic agent page 27 page 650 right column pages 876-877

Protective layer The electrophotographic image-receiving paper of the present invention is used for the purpose of protecting the surface, improving the storage stability, improving the handleability, imparting the writing property, improving the equipment passage property, imparting the anti-offset property, and the like. A protective layer can be provided on the surface of the toner image receiving layer. The protective layer is
One layer may be used, or two or more layers may be used. For the protective layer, various thermoplastic resins, thermosetting resins, or the like can be used as a binder. Preferably, the same type as the toner image receiving layer is used. However, the thermodynamic characteristics, the 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 protective layer may contain various additives as described above, which can be used in the toner image receiving layer. In particular, for example, a plasticizer, a release agent, a slipping agent, and the like can be blended in the protective layer. The outermost surface layer of the electrophotographic image-receiving paper of the present invention (for example, if a surface protective layer is used, the surface protective layer and the like) are preferably compatible with the toner from the viewpoint of fixability. . Specifically, the contact angle with the molten toner is preferably, for example, 0 to 40 degrees.

Back Layer The purpose of the back side polypropylene resin layer of the present invention is to provide back side output suitability, improve back side output image quality, improve curl balance, and improve equipment passability. Thus, a back layer can be provided. The back layer may have the same configuration as the toner image receiving layer side in order to improve the two-sided output suitability for forming an image on the back surface of the electrophotographic image receiving paper. In the back layer, various additives described in relation to the toner image receiving layer can be used.
It is appropriate to add a charge control agent and the like as such additives. The back layer may be composed of one layer, or may be composed of two or more layers. When a releasing oil is used for the fixing roller or the like to prevent offset at the time of fixing, the back layer may be oil-absorbing.

Optional Other Layers The electrophotographic image-receiving paper of the present invention may have an adhesion improving layer for the purpose of improving the adhesion between the polypropylene resin layer and the toner image-receiving layer. Various additives described above can be blended in the adhesion improving layer. It is particularly preferable to use a crosslinking agent. Further, the electrophotographic image receiving paper of the present invention includes:
In order to improve the toner receptivity, a cushion layer can be provided between the adhesion improving layer and the toner image receiving layer. Further, the electrophotographic image-receiving paper of the present invention may have an intermediate layer in addition to the above-mentioned various layers. For example, the intermediate layer is between the polypropylene resin layer and the adhesion improving layer, between the adhesion improving layer and the cushion layer, between the cushion layer and the toner image receiving layer, between the toner image receiving layer and the storage stability improving layer, and the like. Can be arranged. Of course, in the case of an electrophotographic image receiving paper including a base paper, a polypropylene resin layer, a toner image receiving layer, and an intermediate layer, the intermediate layer is, for example, provided between the polypropylene resin layer and the toner image receiving layer. be able to.

Color Toner for Electrophotography The image receiving paper for electrophotography of the present invention is used in combination with toner or toner particles during printing or copying. The toner used in the present invention can be obtained by either a pulverization method toner or a suspension granulation method toner. In the case of a pulverized toner, it is manufactured by kneading, pulverizing and classifying. Examples of the binder resin used in the production of the pulverized toner include, for example, monomers such as acids such as acrylic acid, methacrylic acid, and maleic acid and esters thereof; polyester; polysulfonate; polyether; The obtained resin or a resin obtained by copolymerizing two or more of these monomers can be used. These resins are produced by sufficiently kneading with a hot kneader such as a hot roll, kneader, extruder or the like together with other toner constituent materials including a wax component, and then mechanically pulverizing and classifying. The toner obtained by such a pulverization method suitably contains a wax component in the range of 0.1 to 10% by weight, preferably 0.5 to 7% by weight based on the weight of the toner. .

In the case of the suspension granulation method toner, a binder, a colorant and a release agent (as needed, a magnetic substance, a charge controlling agent and other additives) are mixed in a solvent which does not have an affinity for water. The obtained composition is coated with a polymer having a carboxyl group, and then dispersed in an aqueous medium in the presence of a hydrophilic inorganic dispersant having a BET specific surface area of 10 to 50 m ² / g and / or a viscosity modifier. If necessary, the obtained suspension is diluted with an aqueous medium, and then the obtained suspension is heated and / or reduced in pressure to remove the solvent, thereby producing a toner. In the present invention, it is particularly preferable to use a toner prepared by the suspension granulation method, and a better result may be obtained than a pulverized toner.

The binder used for the suspension granulation method toner is as follows:
All known binder resins can be used. Specifically, styrene, styrenes such as chlorostyrene, monoolefins such as ethylene, propylene, butylene and isoprene, vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl butyrate, and methyl acrylate Α-methylene aliphatic monocarboxylic esters such as ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate, vinyl Methyl ether, vinyl ethyl ether,

Examples thereof include homopolymers and copolymers of vinyl ethers such as vinyl butyl ether and the like, and vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone. Particularly typical binder resins include polystyrene resin, polyester resin, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, and styrene- Examples include a maleic anhydride copolymer, a polyethylene resin, and a polypropylene resin. Further, polyurethane resins, epoxy resins, silicone resins, polyamide resins, modified rosins, paraffins, waxes and the like can be mentioned. Among these resins, styrene-acrylic resins are particularly preferred for the present invention.

As the coloring agent to be contained in the toner binder, any known coloring agent can be used. For example, carbon black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, Dupont oil red, quinoline yellow,
Methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, C.I. I. Pigment Red 48: 1, C.I.
I. Pigment Red 122, C.I. I. Pigment
Red 57: 1, C.I. I. Pigment Yellow 97,
C. I. Pigment Yellow 12, C.I. I. Pigment Yellow 17, C.I. I. Pigment Blue 15:
1, C.I. I. Pigment Blue 15: 3 can be exemplified as a typical example. Suitably, the content of the coloring agent is, for example, 2 to 8% by mass. When the content of the colorant is less than 2% by mass, the coloring power is weakened, and when the content is more than 8% by mass, the transparency of the color toner is deteriorated.

It is preferable that the toner contains a release agent. As the release agent, for example, wax is preferably used, and specifically, polyethylene, polypropylene, low molecular weight polyolefins such as polybutene; silicone resin softened by heating, oleamide,
Fatty acid amides such as erucamide, ricinoleamide, and stearamide; plant waxes such as carnauba wax, rice wax, candelilla wax, wood wax, and jojoba oil; animal waxes such as beeswax; montan wax; Mineral and petroleum waxes such as ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, and modified products thereof can be used. In general, when a wax containing a highly polar wax ester such as carnauba wax or candelilla wax is used, the release amount of the wax on the surface of the toner particles is large. Also, waxes having a small polarity such as paraffin wax tend to reduce the amount of exposure to the surface.

Regardless of the tendency of the wax to be exposed on the surface, the wax preferably has a melting point in the range of 30 to 150 ° C., more preferably 40 to 140 ° C. The toner used in the present invention is mainly composed of the colorant and the binder, and has an average particle diameter of 3 to 15%.
μm, particularly 4 to 8 μm is preferably used. The storage elastic modulus G ′ of the toner at 150 ° C. (measured at an angular frequency of 10 rad / sec) is 10 to 10.
It is preferably in the range of 200 Pa. Further, an external additive may be added to the toner of the present invention. Fine powders of inorganic compounds and fine particles of organic compounds are used as external additives. The inorganic compound fine particles are SiO ₂ , TiO ₂ , Al
₂ O ₃ , CuO, ZnO, SnO ₂ , Fe ₂ O ₃ , Mg
O, BaO, CaO, K ₂ O, Na ₂ O, ZrO ₂ , C
aO.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 can be exemplified. Further, as the organic compound fine particles, fine powders of fatty acids or derivatives thereof, metal salts thereof, and the like, and fine resin powders such as a fluorine resin, a polyethylene resin, and an acrylic resin can be used.

Image Forming Apparatus and Method The method of forming an image on the electrophotographic image receiving paper of the present invention is not particularly limited. It can be applied to various electrophotographic methods. For example, a color image can be preferably formed on the electrophotographic image-receiving paper of the present invention. The formation of a color image can be performed using an electrophotographic apparatus capable of forming a full-color image. A typical electrophotographic apparatus includes an image receiving paper transporting section, a latent image forming section, and a developing section disposed in the vicinity of the latent image forming section. And a toner image intermediate transfer unit in the vicinity of the image transfer unit and the image receiving paper transport unit.

Further, as a method for improving image quality, instead of electrostatic transfer or bias roller transfer,
Alternatively, an adhesive transfer method or a heat-assisted transfer method is known in combination. For example, JP-A-63-113576,
Japanese Patent Application Laid-Open No. Hei 5-341666 describes the specific structure. In particular, a method using a heat-assisted transfer type intermediate transfer belt is preferable when a toner having a small particle size (7 μm or less) is used. As the intermediate belt, for example, an endless belt formed of electroformed nickel and having a silicone or fluorine-based thin film on the surface and imparting a peeling property is used. Further, it is preferable to provide a cooling device on the intermediate belt after the toner is transferred to the electrophotographic image receiving paper or in the latter half of the transfer. The cooling device cools the toner below the softening temperature or glass transition temperature of the binder used therein, efficiently transfers the toner to the electrophotographic image receiving paper, and enables the toner to be separated from the intermediate belt.

Fixing is an important step that affects the gloss and smoothness of the final image. As a fixing method, a fixing method using a heating and pressing roller, a belt fixing method using a belt, and the like are known, but a belt fixing method is more preferable from the viewpoint of image quality such as gloss and smoothness. For the belt fixing method,
For example, an oilless type belt fixing method described in JP-A-11-352819,
No. 71, Japanese Patent Application Laid-Open No. 5-341666, and the like, methods for simultaneously achieving secondary transfer and fixing are known. The surface of the fixing belt is preferably subjected to a silicon-based or fluorine-based surface treatment or a combination thereof in order to prevent toner releasability or toner component offset. It is preferable that a belt cooling device be provided in the latter half of the fixing so that the electrophotographic image receiving paper can be peeled well. The cooling temperature is preferably lower than the softening point or glass transition point of the toner binder and / or the polymer of the toner image receiving layer of the electrophotographic image receiving paper. on the other hand,
In the early stage of fixing, it is necessary to raise the temperature to a temperature at which the toner image-receiving layer of the electrophotographic image-receiving paper or the toner is sufficiently softened. Specifically, the cooling temperature is preferably 70 ° C. or lower and 30 ° C. or higher for practical use.
0 ° C. or higher is preferred.

[0075]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, these Examples and Comparative Examples do not limit the scope of the present invention. In addition,
In the following Examples and Comparative Examples, "%" and "part"
Represents "% by mass".

Example 1 A single-screw extruder (diameter of 60 g / m ² )
mm screw extruder), a polypropylene resin layer having a thickness of 30 μm was laminated on the front and back surfaces by melt extrusion under the following lamination conditions. The MFR of the polypropylene resin in the polypropylene resin layer was 40, and the density was 0.900. Line speed: 100 m / min Corona output: 0.05 kw / cm ² · min Extrusion temperature: 305 ° C. Nip pressure: 40 kg / cm ² Chill roll temperature: 15 ° C. Chill roll surface type: front mirror surface, back surface mat surface

After the corona discharge treatment was applied to the polypropylene resin layers provided on both sides of the obtained laminate, the undercoat layer composition having the following composition was dried by a wire coater to a coating amount of about 0.1 g / d. It was applied and dried to obtain m ² . <Composition for undercoat layer> Gelatin 5 g Water 1000 g

Next, on the surface polypropylene resin layer,
A toner image-receiving layer composition having the following composition was applied using a wire coater so that the coating weight when dried was 8 g / m ² , and dried to form a toner image-receiving layer. <Composition for Toner Image Receiving Layer> Polyester resin (Tuffton U-5, manufactured by Kao) 400 g Titanium dioxide (Taipec (registered trademark) A-220, manufactured by Ishihara Sangyo) 60 g TPP (manufactured by Daiichi Kagaku) 34.8 g Methyl ethyl ketone 800 g Note) TPP is triphenyl phosphate used as a plasticizer.

Next, a composition having the following composition was applied as a protective layer on the toner image-receiving layer to a coating weight of 0.1% when dried.
The composition was applied so as to be 8 g / m ² and dried to form a protective layer. <Protective layer> A515GB (manufactured by Takamatsu Yushi) 1790 g LX814 (manufactured by Nippon Zeon) 491 g water 8900 g SH7028A (manufactured by Toray Silicon Dow Corning) 740 g Note) A515GB is a water-dispersed polyester resin.
LX814 is a water-dispersed acrylic resin used as a binder. SH7028A is a silicone rubber having a siloxane structure used as a slip agent or a release agent.

Next, a back layer composition having the following composition was applied to the back surface of the polypropylene resin layer using a bar coater so that the dry film weight became 4.5 g / m ² , and dried to form a back layer. Formed. <Composition for back layer> Polyester resin (Vylonal MD-1200, manufactured by Toyobo) 90 g Matting agent (Eposter L15, manufactured by Nippon Shokubai) 50 g Water 10,000 g Note) Eposter L15 as a matting agent has a melting point and a glass transition temperature. In the differential thermal analysis, it is a polymer particle having an average particle size of 12 μm and consisting of a benzoguanamine-formaldehyde condensate which starts to decompose at 300 ° C.

The obtained electrophotographic image-receiving paper was cut into A4 sheets to obtain print images. The printer used was a Fuji Xerox color laser printer (DocuColor) except that the fixing belt system shown in FIG. 1 was used.
1250-PF). That is, as shown in FIG. 1, in the fixing belt system 1, the heating roller 3 and the tension roller 5
The cleaning belt 6 is provided above the tension roller 5 via the fixing belt 2, and the cleaning roller 6 is provided below the heating roller 3 via the fixing belt 2. A pressure roller 4 is provided. The electrophotographic image receiving paper having the toner latent image is shown in FIG.
At the right side, the sheet is inserted between the heating roller 3 and the pressure roller 4 and is fixed, and then moves on the fixing belt 2 and is cleaned by the cleaning roller 6. In this fixing belt system, the conveying speed of the fixing belt 2 is 30 mm / sec, and the heating roller 3 and the pressing roller 4
Nip pressure between 0.2 MPa (2 kgf / cm
² ), and the set temperature of the heating roller 3 is 150 ° C., which corresponds to the fixing temperature. Note that the set temperature of the pressure roller 4 was set to 120 ° C.

Evaluation Method The image from the computer was printed as a single black color. The foamability of the toner-fixed surface of the printed sample and the smearing property on the fixing roll were evaluated by sensory evaluation as “〇” when excellent, “△” when slightly inferior, and “×” when inferior. In addition, as an overall evaluation, a case of good was indicated by 〇, a case of impractical was indicated by △, and a case of bad was indicated by ×.

Comparative Examples 1 to 4 Example 1 was repeated except that a polyethylene resin was used instead of the polypropylene resin material used for the polypropylene resin layer, or that the MFR and density of the polypropylene resin material used were changed. Was repeated. Example 1
Table 1 shows the results of Comparative Examples 1 to 4, including the results of

[0084]

[Table 1] (A: polypropylene resin, B: polyethylene resin)

As can be seen from the above results, the specific MF
It can be seen that by providing a polypropylene resin material having R and density in direct contact with both sides of the base paper, an electrophotographic image receiving paper having an image with excellent gloss and image quality can be obtained. In addition, as shown in Comparative Example 1 using a polyethylene resin, when fixing is performed at a high temperature, blisters are generated between the base paper and the resin layer, and the gloss and the image quality are significantly reduced. Further, as can be seen from the results of Comparative Examples 2 to 4, MF
If a polypropylene resin having an R and density other than those specified is used, an electrophotographic image receiving paper having excellent glossiness and image quality cannot be obtained.

[0086]

According to the present invention, according to a simple method,
An image excellent in glossiness and image quality can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a fixing belt system in a printer used in an embodiment.

[Explanation of symbols]

 Reference Signs List 1 fixing belt system 2 fixing belt 3 heating roller 4 pressure roller 5 tension roller 6 cleaning roller

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F100 AK07B AR00C BA03 BA07 BA10A BA10C DG10A GB41 JA06B JD14C JN21 YY00B

Claims (1)

[Claims] 1. An electrophotographic image receiving paper comprising: a base paper; a polypropylene resin layer provided directly on both surfaces thereof; and a toner image receiving layer provided on one or both of the polypropylene resin layers. An electrophotographic image-receiving paper, wherein the polypropylene resin constituting the polypropylene resin layer has a melt flow rate (MFR) of 18 to 50 and a density of 0.890 or more.