JP2006276841A - Recording material for electrophotography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording material for electrophotography which has an superior toner image, high transfer properties, and high image density, and is improved in toner fixability, toner scatter preventiveness, printing unevenness preventiveness, and image density and is also improved in transport performance for photographic papers inside a printer. <P>SOLUTION: In the recording material for electrophotography is formed by providing a toner-fixing layer containing tin oxide on at least one surface of a plastic film, tin dioxide is used as the tin oxide; and the top surface of the toner-fixing layer, under a condition of temperature of 23°C and 50% relative humidity, has a surface resistivity value A (Ω) of 1×10<SP>9</SP>to 1×10<SP>14</SP>Ω and the ratio (B/A) for the volume resistivity value B (Ω cm) of the recording material under the condition of 23°C temperature and 50% relative humidity is adjusted to be within the range of 1×10<SP>2</SP>to 1×10<SP>5</SP>. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recording material for electrophotography, and more specifically, has a relationship in which a surface specific resistance value of a toner fixing layer containing stannic oxide and a volume specific resistance value of the recording material are correlatedly restricted. The present invention relates to a recording material for electrophotography that is practically desirable.

Since the electrophotographic method does not require a plate and a high-accuracy image can be obtained at a high printing speed, it has been widely used in laser beam printers and copiers, and in recent years, especially for stickers and overhead projector (OHP) sheets. There is an increasing demand in the field of using transparent recording materials.
Conventionally, as a recording material in an electrophotographic system, a material in which a toner fixing layer is provided on the surface of a base material has been widely used. For example, a plastic film having a toner fixing layer containing a metal compound or the like on its surface has been used. The toner fixing layer is usually formed by a method in which a metal compound or the like is mixed in a coating resin solution, and the toner fixing layer is coated and formed to an appropriate film thickness.

In a conventional electrophotographic recording material using such an image receiving toner fixing layer, the surface specific resistance of the fixing layer is 1 × 10 ^{9 in} order to obtain good transferability of toner images and high image density. It is said that it needs to be in the range of ˜1 × 10 ¹⁴ Ω (see Patent Document 1). However, even if the toner fixing layer is adjusted to such a surface specific resistance value, it is difficult to satisfy all of the toner fixing property, toner scattering prevention property, printing unevenness prevention property, image density, etc. at the same time. Therefore, there is a demand for a further improved recording material that can satisfy all of the above, and from the practical aspect, there is also a demand for improved transportability in the printer.

JP 2003-43722 A

  In general, synthetic resins are easily charged with static electricity, and in particular, in an electrophotographic system, since the base film is easily electrostatically charged during printing, the printed products that are printed out are stuck to each other and cannot be aligned. There was a problem that the phenomenon occurred and the workability was lowered. Also, many electrophotographic printers apply high heat to the recording material, and there is a restriction that a resin having high heat resistance must be used when used in such a printer.

  In addition to a good toner image, high transferability, and high image density, the present inventor has made many prototypes regarding the formation of a toner image-receiving layer in an electrophotographic system in order to overcome the above improvement problems. In the prototype research, first, attention was paid to the conductive tin oxide compound contained in the toner fixing layer, and further, various resins forming the toner fixing layer were examined. As a result, stannic oxide is used as the tin oxide compound, and the electrical resistance between the surface specific resistance value (Ω) of the toner fixing layer containing the tin oxide compound and the volume specific resistance value (Ω · cm) of the recording material. It has been found that the above-mentioned problems can be effectively overcome by controlling the ratio within a specific range.

  Accordingly, an object of the present invention is to provide an electrophotographic film having a good toner image, high transferability and high image density, as well as improved toner fixability, toner scattering prevention, printing unevenness prevention and image density. It is to provide a recording material. Another object is to provide an electrophotographic recording material having improved photographic paper transportability in a printer. Other problems and technical features of the present invention will become more apparent from the following description.

The present invention relates to a recording material for electrophotography in which a toner fixing layer containing tin oxide is provided on at least one side of a plastic film, wherein stannic oxide is used as the tin oxide, and the temperature is 23 ° C. and 50% relative The surface of the toner fixing layer under humidity conditions is 1 × The surface resistivity value A (Ω) in the range of 10 ⁹ to 1 × 10 ¹⁴ Ω, and the volume resistivity value B (23 ° C. and 50% relative humidity conditions of the recording material) An electrophotographic recording material is provided in which the ratio (B / A) of (Ω · cm) is adjusted within the range of 1 × 10 ² to 1 × 10 ⁵ .

Further, according to the present invention, the surface resistivity of the surface of the electrophotographic recording material and the toner fixing layer in which the stannic oxide is amorphous stannic oxide is 1 × 10. The volume resistivity value B (Ω · cm) of the recording material is within the range of ¹⁰ to 1 × 10 ¹³ Ω and the temperature of 23 ° C. and the relative humidity of 50% is 1 × 10 ¹³ to Provided is an electrophotographic recording material which is in the range of 1 × 10 ¹⁶ Ω · cm and whose ratio (B / A) is adjusted in the range of 1 × 10 ² to 1 × 10 ⁵ .

  According to the present invention, not only a good toner image, high transferability and high image density, but also toner fixing property, toner scattering prevention property, printing unevenness prevention property and image density are improved, and further, transportability within a printer is improved. An electrophotographic recording material having improved and high practicality is provided.

  The plastic used for the base film of the electrophotographic recording material of the present invention is not particularly limited. For example, various polyesters represented by polyethylene terephthalate, cellulose esters, polysulfone, polyphenylene oxide, polyimide, Common synthetic resins such as polycarbonate, polyamide, vinyl chloride, polypropylene and polystyrene are included. These resins are appropriately selected and used according to their required performance when transparency is required or when heat resistance is required. In addition, it can be suitably used for creating a special printing member in which a transparent sticker other than the pattern portion is made and pasted on a window glass.

  When high heat is applied to the recording material, a base film having high heat resistance such as polyester is preferably used, and in the case of a colored base film or an opaque base film, In the film resin, for example, an organic colorant and an inorganic fine powder such as silica or calcium carbonate added to the base resin are used. Furthermore, opaque foamed plastic films containing fine bubbles or cavities inside the film can also be used. The formation of such bubbles and cavities is formed by stretching a film containing inorganic powder such as calcium carbonate to generate bubbles around the inorganic powder (micro void film) or by adding foaming agent and heating foam. However, there are no restrictions on the formation method, the bubbles, the state or form of the cavities, and the like. Examples of the foamed plastic film include “Toyopearl Film P4258” manufactured by Toyobo Co., Ltd. and “Yupo FPG 80” manufactured by YUPO Corporation. Moreover, synthetic paper can also be used for the base material plastic film of the recording material of the present invention.

  In recent years, the adverse effects of plastics on the global environment have been emphasized, and biodegradable plastics have come to the spotlight. In general, biodegradable plastics are characterized by low combustion energy and no generation of toxic gases. They are environmentally friendly plastics that are decomposed and metabolized by microorganisms over time, and eventually return to nature as water and carbon dioxide. However, such a plastic can be used for the base film for an electrophotographic recording material of the present invention. The biodegradable plastic typically includes polylactic acid, a mixture of starch and modified polyvinyl alcohol, polybutylene succinate / adipate copolymer, polycaprolactone, polyhydroxybutyrate / valerate copolymer and the like. In particular, polylactic acid is preferable from the viewpoint of the speed of decomposition and strength. In addition, in order to improve the strength of the base film, other plastics can be added to and mixed with the biodegradable plastic as long as the biodegradability is not impaired.

  The substrate film of the present invention may have a single layer structure or a multilayered structure having a laminated shape. As a method of forming a plastic film having a multilayer structure, for example, a method of laminating films via an adhesive, a so-called laminated film is formed by laminating a plurality of raw materials from a plurality of extruders while extruding them into a film shape. Various known methods such as a co-extrusion method or a so-called extrusion laminating method in which a film is directly laminated onto a film while being extruded from an extruder can be employed.

  In addition, the base film is a method of roughening the surface of the base film by an oxidation method or a concavo-convex forming method in order to improve adhesion strength by improving adhesion and wettability with the toner fixing layer. Is widely adopted. Typical examples of the oxidation treatment method include corona discharge treatment and hot air treatment, and examples of the unevenness formation method include a sand blast method and a solvent treatment method. These surface treatment methods are appropriately selected depending on the type of substrate, but generally, corona discharge treatment methods are preferably used from the viewpoint of treatment effect and operability. Furthermore, a generally known easy adhesion treatment can be performed.

  The stannic oxide-containing toner fixing layer formed on the surface of the plastic base film may be formed by directly applying the coating liquid to the base film, but this improves the adhesive strength of the toner fixing layer. Therefore, an anchor coat may be applied to the surface of the film. For such an anchor coat, substances having good affinity or mutual solubility in both layers are selectively used depending on the type of resin of the base film and the type of resin used in the toner fixing layer. Such substances can be easily selected and determined empirically by those skilled in the art. Generally, this anchor coat layer is dissolved in an organic solvent that dissolves a selected resin component, or a dispersed coating solution is prepared and applied to the surface of a base film, and usually a relatively thin dry film. A thick film is formed. There is no limitation on the application means for forming such a coating film. For example, various conventionally known methods such as reverse roll coating, air knife coating, gravure coating, blade coating, comma coating, and wire bar coating should be used. Can do. The applied anchor coat coating solution is dried and desolvated to form a film that adheres firmly to the surface of the substrate film.

  In the electrophotographic recording material of the present invention, as described above, the toner fixing layer is formed on the base film directly or via an anchor coat layer. Examples of the binder for forming the toner fixing layer include polyester resin, urethane resin, acrylic resin, polyvinyl alcohol, polyvinyl butyral, gelatin, polyvinyl acetal, carboxymethyl cellulose, polyvinyl pyrrolidone, chlorinated polypropylene, and vinyl versatate. Resin, styrene-acrylic copolymer, ethylene-vinyl acetate copolymer, and styrene-butadiene rubber. These may be used alone or in combination of two or more. The use amount range of these resins is usually 40 to 80% by mass based on the solid content in the toner fixing layer. When the content is 40% by mass or more, excellent strength of the toner fixing layer can be obtained, and when the content is 80% by mass or less, excellent print quality can be obtained. A preferred resin usage range is 50 to 70% by mass.

In the toner fixing layer of the present invention, stannic oxide is used as the conductive fine particle material mixed and dispersed in the resin. The use amount range is an amount range usually used in the technical field, and is, for example, a range of 20 to 50% by mass based on the solid content of the toner fixing layer. When the content is 20% by mass or more, excellent antistatic performance can be obtained, and when the content is 50% by mass or less, high strength of the toner fixing layer can be obtained. A practically preferable use amount range is 30 to 40% by mass. This added amount of stannic oxide is extremely useful for maintaining the toner fixing layer at an appropriate surface resistivity. For the toner fixing layer of the recording material of the present invention, amorphous stannic oxide is particularly preferably used. In general, when a tin compound is contained in the toner fixing layer, an antimony-doped one is used, but the problem that antimony is easily separated in the process of producing a coating liquid for forming the toner fixing layer is used. was there. When antimony is separated, the antistatic effect is lowered and the image quality and transportability are liable to be adversely affected. However, the present inventors have found that in the case of amorphous stannic oxide, excellent antistatic performance can be obtained without doping with antimony or the like. In the present invention, when amorphous stannic oxide is used as stannic oxide, there is no reduction in the antistatic effect in the production process, and stable image quality and transportability can be obtained, which is preferable.
The mass of the toner fixing layer is preferably in the range of 0.1 to 1.0 g / m ² in view of the strength and image quality, and particularly in the range of 0.2 to 0.6 g / m ^2. desirable. This mass refers to the mass of the toner fixing layer itself, and does not mean the mass of the coating liquid when it is provided by coating, for example.

In the electrophotographic recording material of the present invention, in order to obtain good transferability and image density of the toner image, the surface specific resistance value A (of the toner fixing layer under the conditions of a temperature of 23 ° C. and a relative humidity of 50%. Is very important to be adjusted within the range of 1 × 10 ⁹ to 1 × 10 ¹⁴ Ω, and in this connection, the resistance under the same temperature of 23 ° C. and 50% relative humidity measurement conditions. It is also very important to adjust the ratio (B / A) of the recording material volume resistivity B (Ω · cm) to the surface resistivity A (Ω) within the range of 1 × 10 ² to 1 × 10 ^5. It is. The preferable surface specific resistance value A (Ω) of the toner fixing layer of the present invention is 1 × 10 ¹⁰ to 1 × 10 ¹³ Ω, and the preferable volume specific resistance value B (Ω · cm) of the recording material. Is 1 × 10 ¹³ to 1 × 10 ¹⁶ Ω · cm. When the ratio (B / A) deviates from the above range, it is inappropriate because improved toner fixing property, toner scattering prevention property, desired printing unevenness prevention property and high image density cannot be obtained. A preferable ratio range of the (B / A) value is 5 × 10 ^{2 to} 5 × 10 ³ . The ratio (B / A) may be adjusted by adjusting either the surface specific resistance value A (Ω) or the volume specific resistance value B (Ω · cm), or by adjusting both of them. Good.

  For example, the surface specific resistance value can be adjusted by the mass of the toner fixing layer, and is practically very effective. Generally, when the toner fixing layer is thickened and its mass is increased, the surface specific resistance value A (Ω) of the toner fixing layer is lowered. In that case, the volume resistivity B (Ω · cm) of the electrophotographic recording material also decreases. However, since the reduction ratio of the surface specific resistance value A is larger than the reduction ratio of the volume specific resistance value B, the (B / A) value increases as a result. As described above, generally, only by selecting the thickness of the toner fixing layer, the (B / A) value can be set within a desired ratio range. In addition, it can be adjusted efficiently by this method. The thickness can be selected effectively within the preferable mass range of the toner fixing layer.

  Other adjustment methods include selecting the type and content of various additives added to the toner fixing layer, or selecting the pore volume of bubbles in the base film, and the toner fixing layer. It can also be adjusted by adjusting the amount of voids. For example, the surface specific resistance value of the toner fixing layer and the volume specific resistance value of the recording material can be reduced by including silica in the toner fixing layer and selecting the amount thereof. The amount of silica used may be relatively small. For example, by adding about 0.1 to 3% by mass of silica based on the solid content in the toner fixing layer, good transportability and high image quality can be obtained. it can. The range of the preferable addition use amount is 0.5-1.5 mass%. Further, it can be adjusted by selecting a resin to be used in consideration of a method for selecting a resin to be used as a binder, in particular, a difference depending on a kind of a hydrophilic group or a hydrophobic group in the molecule and a content ratio thereof. These adjustments are matters that can be easily selected and determined empirically by those skilled in the art as to which adjustment method is adopted or which technique is selected.

  The above-described measurement conditions of the specific resistance value of the electrophotographic recording material of the present invention, that is, the temperature of 23 ° C. and the relative humidity of 50% need to be specified, and are adjusted as measurement setting conditions. This is selected and adopted based on the view that an extremely stable and accurate measurement value can be obtained.

  Further, the toner fixing layer may contain a lubricant. A part of the lubricant used in the toner fixing layer protrudes from the surface of the toner fixing layer to make it slippery. Conventionally known ones can be used, but the stability of the coating solution for forming the toner fixing layer is stable. Polyolefin waxes such as polyethylene wax are preferable from the viewpoint of properties and influence on toner fixing, and those close to true spheres are effective because their effects are great. Further, the lubricant preferably has a particle diameter of 1.0 to 15.0 μm, a Picat softening point of 100 to 150 ° C., and a minimum film formation temperature of 70 to 150 ° C. The above particle diameter is a numerical value measured by the Coulter counter method. However, if the particle diameter is less than 1.0 μm, the lubricant is buried in the toner fixing layer, so that the effect as a lubricant may not be exhibited. On the other hand, if the thickness exceeds 15.0 μm, the surface of the toner fixing layer becomes uneven, and the toner fixing may be deteriorated and the printability may be deteriorated. A more preferable range of the particle size of the lubricant is 2.0 to 12.0 μm. The Picat softening point is a value measured in accordance with ASTM D1525-70. If the softening point is less than 100 ° C., it may be fused to the fixing roll due to the heat of the fixing roll, which may cause poor conveyance. There is. On the other hand, if the temperature is higher than 150 ° C., the toner may be poorly fixed and printability may be deteriorated. A more preferable range of the Picat softening point is 110 to 140 ° C.

  Further, in the toner fixing layer, a surfactant, an antifoaming agent, an antistatic agent, an ultraviolet absorber, a fluorescent whitening agent, an antiseptic, and a pigment dispersant are added as necessary within the range not impairing the object of the present invention. And various additives such as thickeners can be added. Additives to the toner fixing layer containing these can be applied by being contained in a coating solution for forming the toner fixing layer. The addition of these various additives also changes the surface resistivity value of the toner fixing layer and the volume resistivity value of the electrophotographic recording material, and can be used for adjustment.

  In addition, the electrophotographic recording material of the present invention can be easily obtained by using a highly transparent base material to provide a highly transparent electrophotographic recording material having a haze of 1.0 to 3.0%. It has the advantage that it can be manufactured. However, depending on the application, it is also possible to produce a recording material for electrophotography having a low transparency using a base material having a low transparency.

In the electrophotographic recording material of the present invention, a toner fixing layer is provided on a base film, and an anchor coat layer is interposed as required. Depending on the purpose, for example, an ultraviolet absorbing layer or other layers for preventing curling are used. Can be provided. The electrophotographic recording material of the present invention is provided with a toner fixing layer on at least one side of the base film, and the one provided with the toner fixing layer on both sides of the film is, for example, an opaque plastic as the base. By using a film and printing or printing on both sides, it can be suitably used for the production of POP advertisements suspended from the ceiling of a store.
The method for providing the toner fixing layer is not particularly limited, but in general, it can be provided by applying a coating liquid for forming the toner fixing layer. There is no limitation on the application means, and various conventionally known methods such as reverse roll coating, air knife coating, gravure coating, blade coating, comma coating, and wire bar coating can be used.

  The electrophotographic recording material of the present invention is also highly evaluated in that it is easy to obtain a low charge amount and a high electrostatic decay rate. Further, the low charge amount and the high electrostatic decay rate are one of the factors that reduce toner scattering and printing unevenness and improve the transportability during printing.

Hereinafter, the present invention will be described in more detail with reference to specific examples.
In addition, all coating of the coating liquid was performed by the reverse roll coating method.

Example 1
As the substrate, a transparent polyester film having a thickness of 100 μm [manufactured by Toyobo Co., Ltd., trade name: A8300] was used. Further, as a toner fixing layer coating solution, a uniform mixture of the following components in a mass ratio was prepared and used for manufacturing a recording material.

Stannic oxide (manufactured by Yamanaka Sangyo Co., Ltd., trade name: EPS-12A, solid content concentration 12% by mass, amorphous, undoped) 37.00 parts by mass Urethane resin [manufactured by Asahi Denka Kogyo Co., Ltd., product Name: Adekabon titer HUX-401, solid concentration 37% by mass] 19.37 parts by mass Defoaming agent [manufactured by San Nopco, trade name: SN deformer 480, solid content concentration 100% by mass] 0.03 parts by mass Silica [Sold by Wilber Ellis Co., Ltd., trade name: Gasil 200DF (GASIL 200DF), solid content concentration 100% by mass] 0.12 parts by mass / surfactant [manufactured by Nissin Chemical Industry Co., Ltd., trade name: Olphin EXP-4036, solid Min. Concentration 80% by mass] 0.13 parts by mass / water 108.62 parts by mass

An electrophotographic film in which the toner fixing layer coating liquid is applied to one surface of the base film so that the mass after drying is 0.4 g / m ² and dried to form a toner fixing layer. A recording material was prepared. The surface resistivity of the toner fixing layer of the obtained recording material is 7.8 × 10 ¹¹ Ω, the volume resistivity of the recording material is 7.2 × 10 ¹⁴ Ω · cm, and the B / A value is It was 9.2 × 10 ² . The charge amount of the recording material was 3.45 mV, and the electrostatic attenuation rate was 89.86%.

Example 2
A toner fixing layer is formed on an anchor coat layer formed by coating a coating solution for an anchor coat layer comprising a uniform mixture of the following components on a base material (amount of liquid coating: 8 g / m ² ). An electrophotographic recording material was produced in the same manner as in Example 1 except that was formed.
-Water-dispersed polymer polyester [manufactured by Toyobo Co., Ltd., trade name: Vylonal MD-1500, solid content concentration 30% by mass, solid content Tg: 77 ° C] 25.50 parts by mass, water 165.75 parts by mass The surface resistivity of the toner fixing layer of the recording material is 1.3 × 10 ¹¹ Ω, the volume resistivity of the recording material is 2.1 × 10 ¹⁵ Ω · cm, and the B / A value is 1.6 ×. 10 ⁴ . The charge amount of the recording material was 3.40 mV, and the electrostatic attenuation rate was 91.18%.

Example 3
Except for using a uniform mixture of the following components by mass ratio as the toner fixing layer coating solution and applying the mixture so that the mass after drying was 0.9 g / m ² , the same procedure as in Example 1 was performed. An electrophotographic recording material was prepared.
· Stannic oxide (manufactured by Yamanaka Sangyo Co., Ltd., trade name: EPS-12A, solid content concentration 12% by mass, amorphous, undoped) 21.25 parts by mass · urethane resin [manufactured by Asahi Denka Kogyo Co., Ltd., product Name: Adekabon titer HUX-401, solid content concentration 37% by mass] 19.37 parts by mass. Lubricant: Low molecular weight polyolefin [Mitsui Chemicals, trade name: Chemipearl W-310, solid content concentration 40% by mass, shape. : True spherical shape, particle diameter (Coulter counter method): 9.5 μm, Vicat softening point: 132 ° C., minimum film-forming temperature: 115 ° C.] 0.30 parts by mass / water 108.12 parts by mass The surface resistivity of the toner fixing layer is 1.1 × 10 ¹³ Ω, the volume resistivity of the recording material is 2.1 × 10 ¹⁵ Ω · cm, and the B / A value is 1.9 × 10 ² . there were. The charge amount of the recording material was 1.85 mV, and the electrostatic attenuation rate was 84.05%.

Comparative Example 1
In place of Adekabon titer HUX-401 used in the toner fixing layer coating solution of Example 1, urethane resin [manufactured by Asahi Denka Kogyo Co., Ltd., trade name: Adekabon titer HUX-232, solid concentration: 30 mass %] An electrophotographic recording material was produced in the same manner as in Example 1 except that 25.50 parts by mass were used. The resulting recording material has a toner fixing layer surface specific resistance value of 3.9 × 10 ¹³ Ω, the recording material has a volume specific resistance value of 2.1 × 10 ¹⁵ Ω · cm, and a B / A value of 5 4 × 10 ¹ . The recording material had a charge amount of 5.2 mV and an electrostatic attenuation factor of 21.15%.

The above-mentioned surface specific resistance value, volume specific resistance value, charge amount, and electrostatic attenuation factor are measured and calculated by the following methods.
• Surface resistivity [Ω]; using “High Resistance Meter HP 4339B” manufactured by Yokogawa, Hewlett-Packard as a measuring instrument, and using a toner fixing layer under atmospheric conditions of a temperature of 23 ° C. and a humidity of 50% RH The resistance value of the provided surface was measured according to JIS K6911.
・ Volume resistivity [Ω ・ cm]; “High Resistance Meter HP 4339B” manufactured by Yokogawa-Hewlett-Packard Co. was used as a measuring device, and the temperature was 23 ° C. and humidity was 50% RH. A test piece is placed on a concentric electrode “16008B (trade name)” (inner electrode 50 mm diameter, outer electrode inner diameter 70 mm, outer diameter 80 mm, guard electrode 80 mm diameter) manufactured by Hewlett-Packard Co., and a voltage of 100 V is applied. Then, the resistance value after 1 minute was measured according to JIS K6911.
-Charge amount [KV]: Using a "STATIC HONESTMETER" manufactured by Sicid Electrostatic Co., Ltd., the surface of a 40 mm x 40 mm sample was charged with 10 KV for 1 minute, and the charge amount A (KV) immediately after that was measured.
-Electrostatic decay rate [%]: Measure the charge amount B (KV) 1 minute after the above charge, that is, 1 minute after the end of the charge, and attenuate 1 minute after the charge using the following formula. The rate was calculated.
Decay rate 1 minute after charging = [(AB) / A] × 100 (%)

Further, with respect to the recording materials prepared in Example 1 and Comparative Example 1, the haze degree and the adhesive strength of the toner fixing layer were measured and evaluated by the following methods.
-Haze degree [%]; Measured with "DIRECT READING HAZEMETER" manufactured by TOYOSEIKI.
-Adhesive strength of toner fixing layer: Cellophane tape ("CT405A-18" manufactured by Nichiban Co., Ltd., length 10 cm) is stuck on the toner fixing layer by reciprocating 3 kg of a 2 kg pressure roll, and the direction reverses at an angle of 45 ° (pulling) The degree of peeling when peeling at a peeling angle of 135 ° was evaluated according to the following criteria.
○: The area of the coating layer adhering to the cellophane tape is 30% or less Δ ... The area of the coating layer adhering to the cellophane tape is more than 30% and 60% or less × ... The area of the coating layer adhering to the cellophane tape is 60% Super

    Furthermore, using the recording materials prepared in Example 1 and Comparative Example 1 above, using a commercially available full color laser printer SPEEDIA N5II manufactured by Casio Computer Co., Ltd. and genuine toner, a printed image is created, Image density, toner scattering, and transportability were measured and evaluated by the following methods. The content of the image (1) is a solid of each color of cyan, magenta, yellow, and black created with a dot area ratio of 100% (Illustrator 8.0), and the mode is the peach 1 mode. The content of the image (2) is a full-color image, and the mode is the same peach 1 mode.

Image density: The above "image (1)" was printed, and the reflection density was measured using a Macbeth densitometer RD-918.
Toner scattering; The printed images were visually evaluated according to the following criteria.
○… Toner scattering is very small and image quality is good. △… Toner scattering is small and there is no practical problem. ×… Toner scattering is large and practically troublesome. Transportability; “Image (2)” in 10 consecutive sheets The images were printed and evaluated according to the following criteria.
○ ... No jam, double feed × ... Jam or double feed occurs even with one sheet

    The measured values and the evaluation results are shown in Table 1 below.

Claims (3)

In an electrophotographic recording material in which a toner fixing layer containing tin oxide is provided on at least one surface of a plastic film, stannic oxide is used as the tin oxide, and the temperature is 23 ° C. and the relative humidity is 50%. The surface of the toner fixing layer is 1 × The surface resistivity value A (Ω) in the range of 10 ⁹ to 1 × 10 ¹⁴ Ω, and the volume resistivity value B (23 ° C. and 50% relative humidity conditions of the recording material) The recording material for electrophotography, wherein the ratio (B / A) of (Ω · cm) is adjusted within the range of 1 × 10 ² to 1 × 10 ⁵ . 2. The electrophotographic recording material according to claim 1, wherein the stannic oxide is amorphous stannic oxide. The surface specific resistance value A is in the range of 1 × 10 ¹⁰ to 1 × 10 ¹³ Ω, and the volume specific resistance value B of the recording material is in the range of 1 × 10 ¹³ to 1 × 10 ¹⁶ Ω · cm. The electrophotographic recording material according to claim 1.