JP4381966B2 - Water-resistant electrophotographic image-receiving paper - Google Patents

Description

  The present invention relates to an electrophotographic image receiving paper. More specifically, the present invention relates to an electrophotographic image-receiving paper that is excellent in toner fixing property and transferability in a color copier and has water resistance that does not generate blisters.

  With the colorization and high performance of electrophotographic printers and printers, printed materials have come to be used in a variety of ways, including documents, posters, cards, labels, and documents with color photographs. However, because it is printed on paper, it is inferior in water resistance and antifouling, and it is easy to get dirty with water or oil. Menus of restaurants, fresh food store product cards, posters posted outdoors, etc. are laminated with plastic film after printing. Post-processing such as applying

  Therefore, when electrophotographic printing is performed on paper that has films attached to both sides in advance, the toner that has been fixed when the image is rubbed off, and the toner fixing properties such as scratch resistance and durability are inferior. Inferior transferability, image density is difficult to produce, color saturation is low, and high-quality color images cannot be obtained. When heat fixing during printing, foaming (blister) occurs between the paper and the film due to heat. There have been problems such as paper transportability and poor appearance.

JP 2002-80619 A JP-A-10-114161

  Accordingly, the present invention relates to a water-resistant electrophotographic image receiving paper, and in particular, to provide an electrophotographic image receiving paper that is excellent in toner fixing property and transferability, provides a beautiful image, and does not generate blisters during heat fixing. The purpose is to do.

The present invention has solved the above problems by the following technical configuration.
(1) A plastic film is bonded to both sides of a base paper having a moisture content of 5% or less. At least one side of the plastic film has a glass transition temperature of 0 to 80 ° C. as a main component and a surface resistance of 1 × 10 ⁷ to 1 A water-resistant electrophotographic image-receiving paper comprising a toner receiving layer of × 10 ¹¹ Ω / □ and the base paper impregnated with a resin.
(2) The electrophotographic image-receiving paper having water resistance according to (1), wherein the water resistance from the end face is 4 mm or less .
(3) The electrophotographic image-receiving paper having water resistance according to (1) or (2), wherein the resin impregnation is performed by coating.
(4) The electrophotographic image-receiving paper having water resistance according to any one of (1) to (3), wherein the plastic film is a polyethylene terephthalate film .

  INDUSTRIAL APPLICABILITY The present invention can provide an electrophotographic image-receiving paper that is excellent in toner fixability and transferability, can provide a beautiful high-quality image with excellent durability, and has water resistance that does not generate blisters during heat fixing. .

First, an embodiment of the present invention will be described with reference to FIG.
FIG. 1 shows an example of an electrophotographic image-receiving paper having water resistance. In the figure, reference numeral 1 denotes a water-resistant base paper. A plastic film 3 provided with a toner receiving layer 4 in advance on both sides of the base paper 1 is bonded through an adhesive layer 2 to form an electrophotographic image receiving paper having water resistance.
The thickness of the electrophotographic image receiving paper of the present invention is preferably 70 to 400 μm, more preferably 100 to 300 μm. For cards and photographs, 150 to 300 μm is preferable. If it is less than 70 μm, the rigidity is insufficient, and it is not suitable for cards and photographs, and there is a risk of poor conveyance with an electrophotographic printing machine or printer. There is a risk of poor transport.
The thickness of the base paper and the plastic film can be appropriately selected depending on the total thickness of the electrophotographic image receiving paper, but it is advantageous in terms of material cost to increase the thickness of the base paper relative to the total thickness. It is.
1-50 micrometers is preferable and, as for the thickness of a contact bonding layer, 5-20 micrometers is more preferable.
The thickness of the toner receiving layer is preferably 0.01 to 10 μm, more preferably 0.05 to 5 μm.

Next, embodiments of the present invention will be described in detail.
<Base paper>
As the base paper of the present invention, any of high quality paper, medium quality paper, lower grade paper mainly using wood pulp can be used. Further, it may contain non-wood pulp, synthetic pulp, synthetic fiber and the like.
The basis weight of the base paper is not particularly selected, but a paper having a basis weight of 50 to 250 g / m ² can be used depending on the application. If it is less than 50 g / m ^{2, the} stiffness of the paper is insufficient, and if it exceeds 250 g / m ² , the stiffness becomes excessive, and in any case, conveyance failure is likely to occur in a printing machine or the like. On the other hand, if it is less than 50 g / m ² , the rigidity is insufficient and it is not suitable for posters, cards, photographs and the like. The basis weight is preferably 70~220g / ^{m 2,} in the case of such further card applications and color photographic preferably 100 to 200 g / ^{m 2.}

The base paper is required to have water resistance, and it is preferable that water resistance of the cross section, that is, water permeation from the cross section can be prevented. It is also preferable to prevent the penetration of other liquids such as oil.
If the water resistance of the base paper is insufficient, water will permeate from the end face and cause undulation near the end when used in outdoor posters or perishable food product cards. Further, when oil or the like permeates, the vicinity of the end portion becomes transparent.
Methods for imparting water resistance to the base paper include an internal size method that is internally added during papermaking, a surface size method using a size press, etc., a method that uses both, and a method of impregnating (coating) a resin into the base paper after papermaking Etc. In the present invention, in consideration of suppressing penetration of other liquids such as oil, a method of impregnating (coating) a resin into the base paper after paper making is preferable.

  The resin to be impregnated (coated) can be water-based, organic solvent-based, or solvent-free, but generally paper has some water resistance (size is effective) Therefore, since it is difficult to impregnate in an aqueous system, a solvent system and a solventless system are preferable, and a solvent system is preferable for adjusting the amount of resin impregnation. In the solvent system, the resin adhesion amount can be easily adjusted by changing the resin concentration of the impregnating liquid.

The impregnating resin is not particularly limited, but preferably has both water resistance and oil resistance. For example, phenol resin, melamine resin, polyvinylidene chloride resin, polyvinyl chloride resin, polyester resin, polyamide resin, polyurethane Resin, acrylic resin, other thermosetting resin or thermoplastic resin, synthetic resin latex and the like can be used.
The resin adhesion amount is preferably 1 to 20% by weight, more preferably 2 to 10% by weight, and further preferably 2 to 7% by weight based on the base paper. When the adhesion amount is less than 1% by weight, the effect of imparting water resistance is poor. If it exceeds 20% by weight, the paper becomes hard, causing problems in transportability in a printing machine, and the paper becomes transparent, so it may not be suitable depending on the application.
The impregnating solution can be mixed with other chemicals as required. For example, in the present invention, a low resistance treatment agent is preferably contained.

The base paper used in the present invention is required to have a moisture content of 5% or less, more preferably 4.5% or less, and even more preferably 4% or less. If the water content exceeds 5%, blistering is likely to occur during heat fixing.
In addition, the measuring method of a water | moisture content is based on JISP8127.

  The base paper used in the present invention may be colored according to the application. However, in the case of a color photograph, if it is colored, the image becomes dull and the vividness is impaired. In order to make the color image brighter and more vivid, it is also preferable to make the appearance white, and it is preferable to use a fluorescent dye by internal addition or coating at the stage of the base paper.

  The base paper used in the present invention preferably has a Beck smoothness measured by JIS P 8119 of 20 seconds or more, and more preferably 50 seconds or more. If the Beck smoothness is less than 20 seconds, the high-quality image is lost. For photography, 65 seconds or more are preferable. The Beck smoothness can be adjusted with a machine calendar, a super calendar, or the like.

<Plastic film>
Examples of plastic films used in the present invention include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, and polybutylene terephthalate, polyvinyl chloride, polystyrene, polymethyl methacrylate, polycarbonate, cellophane, and cellulose acetate. , Polyarylate, polysulfone and the like. In the present invention, polyester is preferable and polyethylene terephthalate is more preferable from the viewpoints of heat resistance that does not deform during thermal fixing, transportability during printing, water resistance and oil resistance as printed matter, and the like.
The thickness of the film may be appropriately selected according to the total thickness of the electrophotographic image-receiving paper, but is usually selected from 12 to 100 μm.

<Toner receiving layer>
The toner receiving layer is provided in order to improve the transferability and fixing property of the toner and obtain a high quality image. The toner receiving layer is composed of at least a resin for accepting toner, and if necessary, a low resistance treatment agent or organic polymer fine particles. And inorganic fine particles.
As the resin constituting the toner receiving layer, polyolefin resins such as polyethylene and polypropylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, polyacrylate, polyester resin, polyethylene terephthalate, Polybutylene terephthalate, polystyrene resin, polyamide resin, copolymers of olefins such as ethylene and propylene with other vinyl monomers, cellulose resins such as ionomers, ethyl cellulose, cellulose acetate, nitrocellulose, polycarbonate resins, urethane resins, etc. Preferred are vinyl resins, polyester resins, vinyl chloride-vinyl acetate copolymer resins, polyamide resins, and urethane resins. Polyester resins and polyamide resins are preferred. , Urethane resin is more preferable.

The glass transition point (Tg) of the resin is preferably 0 to 80 ° C, more preferably 15 to 65 ° C, and further preferably 30 to 50 ° C. When the Tg is less than 0 ° C., the toner receiving layer is easily deformed when rubbed with another, and the fixed toner is easily peeled off, so that the fixing property is inferior, and the image receiving paper is blocked to cause double feeding. Cheap. On the other hand, when the temperature exceeds 80 ° C., the toner receiving layer tends to be hard, so that heat fixing is difficult, fixing strength is reduced, and fixing property is deteriorated. In order to adjust the Tg of the resin, a plurality of resins having different Tg may be used in combination.
Tg was measured according to JIS K 7121-1987 with the midpoint glass transition temperature (Tmg) described in 9.3 as the Tg of the present invention.

The toner receiving layer of the present invention preferably contains a low-resistance treatment agent in order to optimize surface resistance. As the low-resistance treatment agent, known cationic, anionic, zwitterionic, and nonionic low-resistance treatment agents can be used. Examples of cationic systems include quaternary ammonium salts and polyamine derivatives, examples of anionic systems include alkyl phosphates and polystyrene sulfonates, and examples of nonionic systems include fatty acid esters. In the present invention, a quaternary ammonium salt is preferred.
The content of the low-resistance treatment agent in the toner receiving layer must be adjusted so that the surface resistance of the toner receiving layer falls within an appropriate range, but is preferably 0.01 to 40% by weight. .1 to 20% by weight is more preferable, and 1 to 10% by weight is further preferable. If it is less than 0.01% by weight, the effect of lowering the surface resistance of the toner receiving layer is small. If it exceeds 40% by weight, the surface resistance tends to be too low.

The toner-receiving layer of the present invention preferably contains organic polymer fine particles or inorganic fine particles for the purpose of preventing double feeding due to blocking that occurs when paper is supplied to an electrophotographic printing machine or printer. Examples of the organic polymer fine particles include polyolefin fine particles such as polyethylene, polystyrene fine particles, polyacrylic fine particles, ethylene acrylic acid copolymer fine particles, and the inorganic fine particles include silica, clay, talc, kaolin, silica stone, aluminum hydroxide, Examples thereof include titanium dioxide, aluminum sulfate, zinc oxide, calcium carbonate, and glass beads. These fine particles preferably have an average primary particle diameter of 0.01 to 1 μm.
The organic polymer fine particles and inorganic fine particles are preferably contained in the toner receiving layer in an amount of 0.1 to 10% by weight, more preferably 0.5 to 5% by weight. If it is less than 0.1% by weight, the electrophotographic image-receiving paper is likely to be blocked, and double feeding is likely to occur in a printing machine or printer. If it exceeds 10% by weight, it tends to be detached from the surface of the receiving layer.
In the present invention, inorganic fine particles can be preferably used.

The surface resistance of the toner receiving layer of the present invention is required to be 1 × 10 ⁷ to 1 × 10 ¹¹ Ω / □, and preferably 1 × 10 ⁸ to 1 × 10 ¹⁰ Ω / □. If it is less than 1 × 10 ⁷ Ω / □, transfer becomes difficult and image unevenness is likely to occur. If it exceeds 1 × 10 ¹¹ Ω / □, fog may occur in the non-image area during transfer.
The value of the surface resistance is a value measured in an environment of 23 ° C./65% RH using a product name: KAWAGUCHI TEROOHM METER VE-30, manufactured by Kawaguchi Co., in accordance with JIS K 6911-1995 5.13.1. It is.

  The toner receiving layer of the present invention may be formed on one side or both sides depending on the application, but the surface resistance is preferably in the above range on both sides, and the same on the non-image side in terms of the balance between the front and back sides. It is preferable to form the layer.

The coating amount of the toner receiving layer is preferably ^{0.01~10g / m 2, 0.05~5g / m} 2 is more preferable. If it is less than 0.01 g / m ² , the purpose of the toner receiving layer cannot be achieved. On the other hand, if it exceeds 10 g / m ² , the effect as the toner receiving layer reaches its peak, resulting in an increase in material costs and production. This is not preferable because it causes a decrease in property.

The method for forming the toner receiving layer is as follows.
Resin, low-resistance treatment agent, inorganic fine particles, and other materials are dissolved and dispersed in a solvent to prepare a coating solution. A predetermined amount of this coating solution is applied by the known coating method described below.
Known coating methods are roughly classified into a roll type, a bar type, a blade type, and an air knife type. Examples of the roll type include a size press, a metering size press, a consolidated coater, a contra coater, a gate roll coater, a KCM coater, a gravure coater, and a reverse roll coater. Examples of the bar type include a metal ring bar coater and a comma bar coater. In the blade type, there are a bevel blade type and a vent blade type in how to apply the blade. Examples of the shape of the head include a bond blade coater, a flexi blade coater, a flooded nip coater, a fountain blade coater, a champ flex coater, and a bill blade coater. It can also be applied by screen printing.
In the present invention, a gravure method that can easily and accurately apply a relatively low viscosity liquid can be preferably applied.

<Adhesive layer>
The adhesive layer is composed of at least an adhesive resin, and is composed of an adhesive containing a low-resistance treatment agent or the like as necessary.
The adhesive resin used in the adhesive layer is not particularly limited as long as it has an adhesive function, and a thermoplastic resin adhesive resin, a thermosetting resin adhesive resin, or a rubber (elastomer) adhesive resin should be used. Can do.
The thermoplastic resin-based adhesive resin can be used in the form of a solution, emulsion, or latex. Examples of the resin component include polyvinyl acetate, polyvinyl alcohol, polyvinyl acetal, polyvinyl alkyl ether, cyanoacrylate, polyvinyl chloride, polyamide, polymethacrylic ester such as polymethyl methacrylate, and polyacrylic ester such as polymethyl acrylate. , Nitrocellulose, cellulose acetate, polystyrene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, thermoplastic epoxy, copolymer of monomers constituting the polymer, and derivatives of the polymer. Moreover, you may mix and use multiple types of the said resin as needed.

  The thermosetting resin-based adhesive resin is generally liquid at room temperature, and is cured by heating or mixing two or three components such as a catalyst, a curing agent, and a curing accelerator. Examples of the resin include melamine resin, urea resin, phenol resin, resorcinol resin, furan resin, epoxy resin, unsaturated polyester resin, polyurethane resin, polyimide resin, polyamideimide resin, polybenzothiazole resin, polybenzimidazole resin, etc. Can be mentioned. Usually, a two-component curable adhesive using a main agent and a curing agent is preferably used.

Rubber (elastomer) -based adhesive resin is an elastic polymer compound whose main component is natural rubber or synthetic rubber. Natural rubber, recycled rubber, styrene-butadiene rubber, acrylonitrile butadiene rubber, chloroprene rubber, butyl rubber, isoprene. Rubber etc. are mentioned.
The adhesive resin used in the present invention is preferably a two-component curable polyurethane resin.

In the adhesive constituting the adhesive layer of the present invention, it is preferable to contain a low-resistance treatment agent in the adhesive in order to improve toner transferability, thereby reducing the surface resistance of the adhesive layer.
As the low-resistance treatment agent, known cationic, anionic, zwitterionic, and nonionic low-resistance treatment agents can be used. Examples of cationic systems include quaternary ammonium salts and polyamine derivatives, examples of anionic systems include alkyl phosphates and polystyrene sulfonates, and examples of nonionic systems include fatty acid esters. In the present invention, a quaternary ammonium salt is preferred.
The content of the low-resistance treatment agent in the adhesive is preferably 0.1 to 15% by weight, more preferably 0.5 to 10% by weight, based on the solid content of the adhesive. If it is less than 0.1% by weight, the effect of reducing the surface resistance is not achieved. If it exceeds 15% by weight, the adhesive strength is lowered, which is not preferable.
In the adhesive, a colorant such as a color pigment, a color dye, or a fluorescent dye can be mixed as necessary.

In this invention, 1-50 g / m < ² > is preferable and, as for the coating amount of the said adhesive agent, 5-20 g / m < ² > is more preferable. If it is less than 1 g / m ² , uniform adhesion cannot be achieved, and the adhesive strength is insufficient. If it exceeds 50 g / m ² , the amount is more than necessary, which increases the cost.

The surface resistance of the adhesive layer is preferably 1 × 10 ⁸ to 1 × 10 ¹² Ω / □, and more preferably 1 × 10 ⁹ to 1 × 10 ¹¹ Ω / □. If it is less than 1 × 10 ⁸ Ω / □, the surface resistance tends to be too low and the transferability tends to decrease, and if it exceeds 1 × 10 ¹² Ω / □, fogging is likely to occur in the non-image area.
The method for measuring the surface resistance is the same as in paragraph [0021] above.

<Manufacture of electrophotographic image receiving paper>
The electrophotographic image receiving paper of the present invention is obtained by laminating a plastic film on both sides of a base paper via the adhesive, and examples of the laminating method include the following methods.
(1) Dry lamination (dry bonding)
An adhesive is applied on one base material so that the solvent is almost volatilized, and another base material is stacked on top of the base material by pressure or heating.
(2) Wet lamination (wet bonding)
An adhesive is applied on one base material, and another base material is stacked thereon and bonded together, followed by drying.
(3) Hot melt lamination (thermal melting lamination)
A hot-melt adhesive is applied to one of the substrates in a molten state, and another substrate is immediately bonded to the substrate and cooled.
(4) Heat-seal lamination A heat-meltable material is applied and placed on one base material in advance, and the other base material is stacked and thermocompression bonded. Alternatively, a heat-meltable film is inserted between the two substrates and thermocompression bonded.
(5) Extrusion lamination (melt extrusion lamination)
A molten film-like adhesive resin is extruded and pressure-bonded between both substrates from a T-die of an extruder.

Among the above-described bonding methods, known methods can be appropriately adopted as the coating methods in (1) to (3), and are roughly classified into a roll type, a bar type, a blade type, and an air knife type. Examples of the roll type include a size press, a metering size press, a consolidated coater, a contra coater, a gate roll coater, a KCM coater, a gravure coater, and a reverse roll coater. Examples of the bar type include a metal ring bar coater and a comma bar coater. In the blade type, there are a bevel blade type and a vent blade type in how to apply the blade. Examples of the shape of the head include a bond blade coater, a flexi blade coater, a flooded nip coater, a fountain blade coater, a champ flex coater, and a bill blade coater. It can also be applied by screen printing.
The laminating method employed in the present invention is preferably dry lamination because a plastic film is laminated on both sides of the paper using an adhesive solution.

An example of the method for producing the electrophotographic image receiving paper of the present invention is generally as follows.
(1) A toner receiving layer is provided on one side of a plastic film.
(2) On the other surface of the plastic film, an adhesive is applied to evaporate the solvent and provide an adhesive layer.
(3) The adhesive layer and one side of the base paper are bonded together.
(4) Bond the adhesive layer and the other side of the base paper.

  The electrophotographic image-receiving paper having water resistance according to the present invention preferably has a water resistance of 4 mm or less from the end surface according to the water resistance measurement method described later. If it exceeds 4 mm, water permeates from the end face, and the portion is deformed or transparent, so it is not suitable for outdoor posters, restaurant menus, or fresh food product cards.

Examples of the present invention will be described in detail below. Note that the present invention is not limited to this. Moreover, the part of the mixing ratio of raw materials is part by weight.
<Preparation of base paper>
(Preparation of impregnation solution)
Acrylic resin manufactured by Fujikura Kasei Co., Ltd. (trade name: Acrybase LH101, solid content 40 wt% liquid) was diluted with toluene to obtain a 15 wt% liquid, which was used as an impregnation liquid.
(Preparation of base paper)
A high-quality paper (made by Oji Paper Co., Ltd., trade name: Marshmallow) containing a fluorescent dye having a basis weight of 128 g / m ² is used as a base paper, impregnated with the above impregnating solution, and adhered to a solid content of 5 g / m ^2. It was. The base paper had a thickness of 150 μm and a Beck smoothness of 80 seconds. The water content was adjusted to 4.0%, base paper A, 4.8%, base paper B, and 6.0% to make base paper C.

<Production of toner receiving layer>
(Production of toner receiving layer a)
A toner receiving layer coating solution 1 having the following composition was prepared.
・ Toluene 24.3 parts ・ Methyl ethyl ketone 16.4 parts ・ Hydrophobic silica 0.07 parts (Nippon Aerosil Co., Ltd., trade name: R972, average primary particle size 0.016 μm)
・ Low resistance treatment agent (quaternary ammonium salt) 5.7 parts (manufactured by Nippon Processing Paint Co., Ltd., trade name: No. 1-30, 10% diluted 30% by weight liquid)
Polyester resin A (30% by weight liquid) 5.0 parts (Toyobo Co., Ltd., trade name: Byron GK130, Tg15 ° C.)
Polyester resin B (30% by weight liquid) 10.0 parts (manufactured by Toyobo Co., Ltd., trade name: Byron 60SS, Tg 47 ° C.)
This coating solution is applied to a transparent PET film having a thickness of 38 μm (manufactured by Unitika Ltd., trade name: Embred) by a gravure method so as to have a coating amount of 2 g / m ² , dried, and a toner receiving layer a Was obtained. The toner receiving layer a had a thickness of 2 μm and a surface resistance of 3.0 × 10 ⁹ Ω / □.
In addition, Tg of resin which mixed polyester resin A and B with the said ratio was 36 degreeC. The solid content ratio of the toner receiving layer a is 1.5 parts of hydrophobic silica, 3.6 parts of a low resistance treatment agent, and 94.9 parts of a polyester resin.

(Preparation of toner receiving layer b)
A film b coated with the toner receiving layer b was prepared in the same manner as the toner receiving layer a except that the resin was only 15.0 parts of the polyester resin B. The toner receiving layer b had a thickness of 2 μm and a surface resistance of 3.0 × 10 ⁹ Ω / □. The solid content ratio of the toner receiving layer b is the same as that of the toner receiving layer a.
(Preparation of toner receiving layer c)
The toner receiving layer c is the same as the toner receiving layer a except that the resin is only 15.0 parts of polyester resin C (30% by weight liquid) (product name: Byron 290, Tg 72 ° C., manufactured by Toyobo Co., Ltd.). A coated film c was produced. The toner receiving layer c had a thickness of 2 μm and a surface resistance of 3.0 × 10 ⁹ Ω / □. The solid content ratio of the toner receiving layer c is the same as that of the toner receiving layer a.
(Preparation of toner receiving layer d)
A film d coated with the toner receiving layer d was prepared in the same manner as the toner receiving layer a except that the amount of the low-resistance treatment agent was 11 parts. The toner receiving layer d had a thickness of 2 μm and a surface resistance of 1.0 × 10 ⁸ Ω / □. The solid content ratio of the toner receiving layer d is 1.4 parts of hydrophobic silica, 6.7 parts of a low resistance treatment agent, and 91.9 parts of a polyester resin.
(Preparation of toner receiving layer e)
A film e coated with the toner receiving layer e was prepared in the same manner as the toner receiving layer a except that the amount of the low-resistance treatment agent was 4.0 parts. The toner receiving layer e had a thickness of 2 μm and a surface resistance of 9.5 × 10 ¹⁰ Ω / □. The solid content ratio of the toner receiving layer e is 1.5 parts of hydrophobic silica, 2.6 parts of a low resistance treatment agent, and 95.9 parts of a polyester resin.

(Preparation of toner receiving layer f)
Toner receiving in the same manner as the toner receiving layer a except that the resin is only polyester resin D (30% by weight liquid) (Toyobo Co., Ltd., trade name: Byron GM900, Tg-15 ° C.) 15.0 parts. A film f coated with the layer f was produced. The toner receiving layer f had a thickness of 2 μm and a surface resistance of 3.0 × 10 ¹⁰ Ω / □. The solid content ratio of the toner receiving layer f is the same as that of the toner receiving layer a.
(Preparation of toner receiving layer g)
The toner-receiving layer g was the same as the toner-receiving layer a except that the resin was only polyester resin E (30% by weight liquid) (trade name: Byron GK880, Tg 84 ° C., manufactured by Toyobo Co., Ltd.). A film g coated with was prepared. The toner receiving layer g had a thickness of 2 μm and a surface resistance of 3.0 × 10 ¹⁰ Ω / □. The solid content ratio of the toner receiving layer g is the same as that of the toner receiving layer a.
(Preparation of toner receiving layer h)
A film h coated with the toner receiving layer h was prepared in the same manner as the toner receiving layer a except that the amount of the low-resistance treatment agent was 18 parts. The toner receiving layer h had a thickness of 2 μm and a surface resistance of 6.5 × 10 ⁶ Ω / □. The solid content ratio of the toner receiving layer h is 1.4 parts of hydrophobic silica, 10.6 parts of a low resistance treatment agent, and 88 parts of polyester resin.
(Preparation of toner receiving layer i)
A film i coated with the toner receiving layer i was prepared in the same manner as the toner receiving layer a except that the amount of the low-resistance treatment agent was 1.5 parts. The toner receiving layer i had a thickness of 2 μm and a surface resistance of 4.0 × 10 ¹² Ω / □. The solid content ratio of the toner receiving layer i is 1.5 parts of hydrophobic silica, 1.0 part of a low resistance treatment agent, and 97.5 parts of a polyester resin.

<Preparation of adhesive>
An adhesive having the following composition was produced.
Polyurethane resin (manufactured by Takeda Pharmaceutical Co., Ltd., trade name: Takelac A-367H, solid content 35% by weight) and curing agent (manufactured by Takeda Pharmaceutical Co., Ltd., trade name: Takenate A-7, solid content 80% by weight) ) With a solid content ratio of 2: 1, and a low resistance treatment agent (quaternary ammonium salt, manufactured by Nippon Processing Paint Co., Ltd., trade name: No. 1-30, 30% by weight liquid) ) Was added to a solid content of 4.8% by weight and diluted to 30% by weight with ethyl acetate to obtain an adhesive.

<Preparation of electrophotographic image receiving paper>
Example 1
The adhesive was coated on the uncoated surface of the film a by a gravure method so as to be 10 g / m ² . The thickness of the adhesive layer was 9 μm, and the surface resistance was 5 × 10 ¹⁰ Ω / □. The adhesive layer of the film a and the base paper A were bonded to each side of the base paper by a dry lamination method to obtain the electrophotographic image receiving paper of the present invention.
(Examples 2-6, Comparative Examples 1-5)
The base paper and the film were used in the combinations shown in Table 1, and electrophotographic image receiving papers of Examples 2 to 5 and Comparative Examples 1 to 5 were obtained.

<Evaluation of characteristics>
The electrophotographic image-receiving paper obtained in Examples and Comparative Examples was cut into A4 size, and color printing was performed using a color copier (manufactured by Ricoh Co., Ltd., trade name: IPSIO CX7200). The following various properties were evaluated for each printed matter.
The evaluation methods for various characteristics are as follows.
(1) Water resistance: electrophotographic image-receiving paper is cut into 4 cm × 4 cm, and immersed for 1 hour in red ink liquid (manufactured by Pilot Co., Ltd., trade name: pilot ink / red diluted 100 times with water). The ink permeation width was measured to make the maximum value (mm) water resistance.
(2) Fixability: The toner adhesion portion of the color print sample was scratched at a speed of 10 mm / second with a needle tip to which a load of 100 g was applied, and the degree of toner scraping was visually determined.
○: Cannot be scraped Δ: Can be scraped but has no practical problem ×: Scraped off (3) Transferability: Density unevenness in the toner-attached portion of the color print sample was visually determined.
○: Uniform transfer and no density unevenness △: Density unevenness is observed but there is no practical problem ×: Uneven density is severely untransferred or fog is generated in the non-image area ( 4) Blister: The foaming between the base paper of the image receiving paper discharged from the color copier and the film was visually judged.
○: No foaming is observed Δ: Fine foaming is observed but there is no practical problem ×: Large foaming is observed and the film is completely lifted from the base paper

The evaluation results are shown in Table 1.

As is apparent from the results in Table 1, the electrophotographic image-receiving papers of the present inventions of Examples 1 to 6 are excellent in water resistance, toner fixing property and transferability, and are free from blistering or practically used. There was no problem.
The electrophotographic image-receiving paper of Comparative Example 1 was poor in fixability because the Tg of the resin used for the toner-receiving layer was low.
The electrophotographic image-receiving paper of Comparative Example 2 had poor fixability because the Tg of the resin used for the toner-receiving layer was high.
The electrophotographic image-receiving paper of Comparative Example 3 had poor transferability due to the low surface resistance of the toner-receiving layer.
The electrophotographic image-receiving paper of Comparative Example 4 had fogging and poor transferability due to the high surface resistance of the toner-receiving layer.
The electrophotographic image-receiving paper of Comparative Example 5 was unusable for practical use due to the blisters being severe due to the high moisture content of the base paper.

  The electrophotographic image-receiving paper having water resistance according to the present invention is excellent in water resistance, antifouling property, fixing property and transferability, and does not generate blisters at the time of heat fixing, and a high-quality color image can be obtained. , Labels, color photographs and the like.

It is a schematic diagram of an example of the electrophotographic image-receiving paper having water resistance according to the present invention.

Explanation of symbols

1 base paper 2 adhesive layer 3 plastic film 4 toner receiving layer

Claims (4)

A plastic film is bonded to both surfaces of a base paper having a moisture content of 5% or less. At least one plastic film has a glass transition temperature of 0 to 80 ° C. as a main component and a surface resistance of 1 × 10 ⁷ to 1 × 10 ^11. receiving paper for electrophotography having a water-resistant, characterized in that have a Omega / □ toner-receiving layer, in which the base paper is impregnated.   2. The electrophotographic image-receiving paper having water resistance according to claim 1, wherein the water resistance from the end surface is 4 mm or less. 3. The electrophotographic image-receiving paper having water resistance according to claim 1, wherein the resin impregnation is performed by coating .   The electrophotographic image-receiving paper having water resistance according to any one of claims 1 to 3, wherein the plastic film is a polyethylene terephthalate film.

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