JPH07271079A - Color electrophotographic image receiving sheet - Google Patents

Abstract

PURPOSE:To ensure superior clearness of an image, to prevent the re-transfer of a toner and to also prevent the occurrence of electric discharge marks by forming an antistatic peeling layer on the rear side of a base sheet with an adhesive layer in-between and forming a toner receiving layer having specified surface resistivity on the front side. CONSTITUTION:A toner receiving layer is formed on the front side of a base sheet provided with an undercoat layer in-between. The toner receiving layer contains at least polyester resin having <=30 deg.C glass transition temp., a surface roughening agent and an antistatic agent and has 10<7>-10<11>OMEGA/sq. surface resistivity at 20 deg.C and 65% relative humidity. An antistatic peeling layer is formed on the rear side of the base sheet with an adhesive layer in-between to obtain the objective color electrophotographic image receiving sheet.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color electrophotographic image-receiving sheet, and more specifically, it is possible to obtain a good copy image by using the electrophotographic method not only for a single color but also for a full color, and moreover, a copied image can be obtained. The present invention relates to a color electrophotographic image-receiving sheet that can be attached to any place.

[0002]

2. Description of the Related Art Recently, it has become more and more common to directly record a color image created by a computer or the like by electrophotography. Further, by using a transparent or opaque film having an adhesive layer covered with a release sheet as the recording image-receiving sheet, it can be used not only indoors but also outdoors for displays and display labels, and images can be obtained on paper. Because of its novelty unlike the ones described above, electrophotography is widely used for full-color image formation.

By the way, it is quite difficult to attach and fix a toner image on a base sheet by an electrophotographic method. One of the causes is that the electric resistance of the film surface is high in the copying machine because there is a discharge part such as charging the transferred film at high voltage when transferring the toner on the electrostatic latent image by electrophotography. The discharge marks are generated.
As a method of preventing this discharge mark, it has been proposed to control the electric resistance of the film surface within a certain region. However, in the case of a full-color image, this method transfers toner of four colors, so that the surface resistance is too low. The toner transferred first leaks charge on the transfer target film, the transferability of the toner to the transfer target film thereafter deteriorates, and it is retransferred onto the electrostatic latent image holding member at the time of toner transfer, causing color loss, Problems such as a decrease in image density occur.

Another cause is that when a color image is formed digitally, the density of each color is changed by changing the areas of fine dots and lines, so that the toner image forming the image is formed in the high density portion. The surface is made sufficiently smooth by the heat roll fixing device, but since the unevenness due to the image structure of dots and lines is large in the halftone part and it is not smooth enough, the incident light is refracted and the halftone of the projected image is refracted. When a natural image such as a photograph is reproduced due to a darkened image having a low saturation, a shadow (hereinafter referred to as a pseudo contour) that does not exist in the document is likely to occur in the halftone part.

These are often seen when the base sheet is used as a film, and therefore various electrophotographic image-receiving sheets have been proposed at present. For example, an image receiving sheet comprising a toner receiving layer provided directly or through an undercoat layer on the surface of a base sheet, and the glass transition temperature of the toner receiving layer and the amount of synthetic silica contained in the layer are specified (special feature: JP-A-5-136617), a recording sheet comprising a base sheet, an antistatic layer coated on at least one side thereof, and at least one toner receiving layer coated on the antistatic layer (Japanese Patent Laid-Open No. 5-13615). 3032
No. 29), a transfer film for electrophotography having a layer containing an antistatic agent having a charge opposite to that of a toner provided on at least one surface of a plastic film having a heat resistance temperature of 100 ° C. or higher (Japanese Patent Laid-Open No. Hei 5 (1993) 197184) and the like are known.

However, these conventional image-receiving sheets are not always sufficiently improved. That is, in the conventional color electrophotographic image receiving sheet, discharge marks are prevented from being generated on the surface of the image receiving sheet in order to obtain a full color, retransfer of four toners of magenta, cyan, yellow and black is prevented, toner adhesion and pseudo It is hard to say that it is satisfactory in terms of preventing the generation of contours, and a good quality color copy cannot be obtained.

[0007]

Under the circumstances, the present invention has excellent image clarity, prevents retransfer of toner, prevents the generation of discharge marks, and has excellent adhesion to toner. The purpose of the present invention is to provide a color electrophotographic image-receiving sheet which has no background bleeding, does not generate pseudo contours, has excellent blocking resistance, and can be attached to an appropriate display surface or display portion for use. It is a thing.

[0008]

The inventors of the present invention have conducted various studies on color electrophotographic image-receiving sheets having such preferable characteristics, and as a result, antistatic properties have been provided on the back side of the base sheet via an adhesive layer. A release layer is provided, and the toner receiving layer on the surface side of the base sheet further contains (A) a polyester resin having a predetermined glass transition temperature, (B) a surface-roughening agent and (C) an antistatic agent, and a specific surface. It was found that the object can be achieved by using a material having a resistivity, and the present invention has been completed based on this finding.

That is, according to the present invention, in a color electrophotographic image-receiving sheet in which a toner receiving layer is provided on the surface of a base sheet directly or via an undercoat layer, the (A) glass transition temperature of the toner receiving layer is 30 ° C. It contains at least the following polyester resin, (B) surface-roughening agent and (C) antistatic agent, as well as 10 ⁷ to 10 ¹¹ Ω / □ (20 ° C.,
An image-receiving sheet for color electrophotography, which comprises an antistatic release layer having a surface resistivity of RH of 65%) and which is provided on the back surface of a base sheet via an adhesive layer.

The base sheet used in the present invention is not particularly limited as long as it is suitable for receiving an image. For example, polyester such as polyethylene terephthalate, polyamide such as nylon, polyimide, polypropylene, cellulose acetate, polystyrene and polymethacrylate. Such acrylic resins, polycarbonates, polysulfones, polyvinyl chlorides, polyvinyl fluorides, copolymers of these monomers, etc. are used. Among them, polyester films are preferable, as well as transparent ones, foamed polyethylene. Polyester films such as terephthalate and polyethylene terephthalate kneaded with a white pigment may also be used. The thickness of the base sheet varies depending on the purpose of use and field of use, but is usually selected in the range of 50 to 180 μm, preferably 75 to 125 μm.

An undercoat layer may be provided on one side or both sides of the base sheet. This undercoat layer on one side is for improving the adhesion of the toner receiving layer. As the undercoat layer, for example, a thermoplastic resin such as polyester, polyamide, or acrylic resin is generally used, and a thermosetting resin or an ultraviolet curable resin can also be used, but a thermosetting resin such as saturated polyester is preferable. A plastic polyester resin is used, which may be a water-dispersible type or a solvent-soluble type. The thickness of the undercoat layer is usually 0.1 to 3.0 μm.
m, preferably 0.5 to 1.5 μm.

The toner receiving layer provided on the base sheet or on the undercoat layer formed on the base sheet is
(A) A resin containing at least a polyester resin having a glass transition temperature of 30 ° C. or lower, (B) a surface-roughening agent and (C) an antistatic agent, preferably these (A) components,
It is composed of the component (B) and the component (C), or mainly contains these components (A), (B) and (C).

The form of the toner receiving layer is not particularly limited, but (a) (A) glass transition temperature is preferably 3
Is a single layer containing at least a polyester resin at 0 ° C. or lower, (B) a surface-roughening agent and (C) an antistatic agent,
Alternatively, (C) an antistatic layer containing (C) an antistatic agent is provided on a layer containing (A) a polyester resin having a glass transition temperature of 30 ° C. or lower and (B) a surface-roughening agent. It is a composite layer. In the case of this composite layer, the antistatic layer is formed on the surface of the desired image receiving sheet. Also,
In the case of the above-mentioned single layer, it may be a homogeneous one as a whole, or one showing a gradient functionality, for example, the closer to the surface, the respective content ratios of the (B) component and the (C) component to the (A) component. The component may be continuously adjusted such that the component is gradually increased.

The polyester resin as the component (A) exhibits good adhesion to the toner carried by being appropriately melted during heat fixing. This polyester resin is advantageous in terms of safety since it can be used in an aqueous dispersion system when forming the toner receiving layer. If the glass transition temperature of this polyester resin is too high, the adhesion of the toner deteriorates, which is not preferable. Further, the toner receiving layer may contain a small amount of an appropriate resin other than the polyester resin as the component (A).

As the surface-roughening agent of the component (B), inorganic fine particles and organic fine particles are preferably used. Examples of the inorganic fine particles include silica, clay, quartz, talc, calcium carbonate, magnesium carbonate, Titanium oxide,
Alumina, aluminum hydroxide, etc. may be mentioned, and as the organic fine particles, for example, synthetic resin fine particles such as benzoguanamine resin, crosslinked styrene polymer beads and acrylic resin may be mentioned. The toner receiving layer is the same as (b) above.
In the case of the composite layer form, the inorganic fine particles are preferable as the surface-roughening agent, and silica is particularly preferable. When the toner-receiving layer is of the single layer type (a), organic fine particles are preferable as the roughening agent, and benzoguanamine resin is particularly preferable. These surface-roughening agents are advantageous in reducing the stickiness of the silicone oil coated as a release agent at the time of fixing the toner on the hot roll, and improving the blocking resistance and the writability. In particular, such a stickiness can be further reduced by matting the surface with a surface-roughening agent.

The grain size of the roughening agent is 0.5 to 10 μm.
It is preferable to select m in the range of 2 to 8 μm, because the effect of reducing stickiness of silicone oil and the effect as a release agent at the time of fixing toner on a hot roll are great.

The content of the roughening agent of the component (B) in the toner receiving layer is preferably 5 to 60 parts by weight, more preferably 30 to 50 parts by weight, relative to 100 parts by weight of the polyester resin of the component (A). It is selected within the range of parts by weight. If this content ratio is too small, blocking will occur, and if it is too large, the strength of the coating film will decrease and the adhesion of the toner will also decrease.

As the antistatic agent of the component (C), cationic, anionic and amphoteric antistatic agents are used. Examples of such an antistatic agent include ammonium salts, heterocyclic amines, sulfonium salts and betaine. Amphoteric salts,
Examples thereof include phosphonium salts, and among them, cationic quaternary ammonium salts having excellent image suitability are preferable. Examples of the quaternary ammonium salts include polyvinylbenzyltrimethylammonium chloride, polydiallyldimethylammonium chloride, poly-2-acryloyloxyethyltrimethylammonium chloride, butyl methacrylate-2-methacryloyloxyethyltrimethylammonium chloride copolymer, methyl methacrylate. -A quaternary ammonium salt-based cationic acrylic resin such as 2-methacryloyloxyethyltrimethylammonium chloride copolymer, and the like,
In particular, in the case where the methyl methacrylate / 2-methacryloyloxyethyl trimethyl ammonium chloride copolymer is used, and the toner receiving layer is in the composite form of (b) above,
Excellent adhesion to the layer containing the polyester resin of the component (A), and when the toner receiving layer is in the single layer form of the above (a), the physical properties of the polyester resin of the component (A) are not damaged. Further, it is preferable because it does not bleed on the surface in a short time to cause stickiness or powder blowing on the surface.

The amount of the antistatic agent used varies depending on the type and purpose of use of the antistatic agent, but when the toner receiving layer is in the form of the composite layer (b), it is usually from 0.5 to 5.
1.5 g / m ^2, preferably in the case of in the range of 0.7 to 1.3 g / m ^2, also the toner-receiving layer having a single layer form of (i) is given, (A) component of the polyester resin 100 Usually 50 to 150, preferably 80 to 14 parts by weight.
It is selected in the range of 0 parts by weight. In either case, if the amount of the antistatic agent is too small, discharge marks will be generated and toner will be retransferred, and a clear image will not be obtained, and if it is too large, the density of the toner image and the toner adhesion will decrease. Therefore, a high density and clear image cannot be obtained. Further, the antistatic agent is also effective for improving the electrostatic resistance of the image-receiving sheet, the transportability and the transfer efficiency, suppressing the generation of pseudo contours, and reducing the stickiness of the silicone oil.

The surface resistivity of the toner receiving layer is 1.
0 × 10 ^{7 to} 1.0 × 10 ¹¹ Ω / □ (20 ° C., RH65
%), Preferably 1.0 × 10 ^{8 to} 1.0 × 10 ¹⁰ Ω /
It is necessary to set it in the range of □ (20 ° C, RH 65%). If it deviates from this range, discharge marks are likely to occur in the copying machine, and toner is easily retransferred,
Pseudo contours are likely to occur, and it tends to be difficult to obtain a clear image.

Particularly, the effective toner receiving layer in the case of the above-mentioned (a) single-layer form has a grain size of the roughening agent of the component (B) of 0.5 to 5 μm and the component (C). The antistatic agent is a quaternary ammonium salt-based cationic acrylic resin, particularly a methyl methacrylate-2-methacryloyloxyethyl trimethylammonium chloride copolymer.

The thickness of the toner receiving layer is preferably 5 to 1
It is 5 μm, more preferably 7 to 13 μm. If it is thinner than this range, the adhesiveness of the toner tends to be lowered, and if it is too thick, problems in blocking and transportability tend to occur.

To form the toner receiving layer, a means usually used for forming a laminated thin layer sheet, for example, a method of forming a coating film is used. Preferably, the toner receiving layer is a composite layer of the above (b). In the case of the form, first, a predetermined polyester resin as a main component and a surface-roughening agent are mixed with an appropriate solvent together with an additive component such as a viscosity adjusting agent on the surface of the base sheet, optionally via an undercoat layer. The liquid prepared as described above is applied and dried to form a layer containing a polyester resin as a main component, and then a liquid containing an antistatic agent is applied onto this layer and dried. Further, when the toner receiving layer having the single-layered form (a) is formed, a predetermined polyester resin, a surface-roughening agent and an antistatic agent are provided on the surface of the base sheet via an undercoat layer as the case may be. It is preferable that a liquid prepared by mixing with a suitable solvent together with an additive component such as a viscosity modifier is applied and dried.

As the viscosity modifier, thickeners such as polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, polyvinyl butyral are preferable.

In the present invention, in order to provide an antistatic release layer on the back surface of the base sheet via an adhesive layer, it is preferable to prepare a release sheet having an antistatic layer on the surface as an antistatic release layer. It is convenient to provide an adhesive layer on the back surface of the release sheet and then attach the adhesive layer surface to the back surface of the base sheet. This pressure-sensitive adhesive layer is mainly composed of a pressure-sensitive adhesive, and is composed of a pressure-sensitive adhesive alone, or various additive components such as a plasticizer, a filler, a curing agent, and a thickener are adhered depending on the application. Those mixed with the agent are preferable. As the adhesive, for example, acrylic,
Examples thereof include cellulose-based, nitrile rubber-based, polyurethane-based, vinyl acetate-based, and melamine resin-based adhesives, and acrylic adhesives are particularly preferable because they have excellent adhesiveness and weather resistance.

The amount of the adhesive used is preferably 10 to 25.
g / m ^2, more preferably 12~20g / m ^2, to a tacky too small than this range decreases. Also, if the amount is too large, the toner will stick out from the image receiving sheet during copying, and the adhesive will stick to the inside of the copying machine or the image receiving surface, making it difficult to obtain a good image.

The release sheet is not particularly limited as long as it protects the pressure-sensitive adhesive from being dried, and examples of such a release sheet include paper and plastic film whose surface is wax-treated, and the like. A plastic film is preferable because it can impart flexibility to the color electrophotographic image-receiving sheet. Examples of the plastic film include polyester such as polyethylene terephthalate, polyamide such as nylon, polyimide, polypropylene, cellulose acetate, polystyrene, acrylic resin such as polymethacrylate, polycarbonate, polysulfone, polyvinyl chloride, polyvinyl fluoride, and the like. Examples include copolymers of monomers.
Of these, polyester films are preferable because they are inexpensive and easily available. In addition to transparent materials, polyester films such as expanded polyethylene terephthalate and polyethylene terephthalate in which a white pigment is kneaded can be used.

The thickness of the release sheet varies depending on the purpose of use and field of use, but is preferably 50-100 μm.
m, more preferably 75 to 90 μm. If the thickness is less than this range, it will be difficult to peel it off by hand, and if it is too thick, the transportability in the copying machine tends to decrease.

In the antistatic layer provided on the surface of the release sheet, the same antistatic agent as that used in the toner receiving layer is used as the antistatic agent, for example, ammonium salts, heterocyclic amines, sulfonium salts, Examples include betaine-based amphoteric salts and phosphonium salts, and among them, cationic quaternary ammonium salts having excellent image suitability are preferable. Examples of the quaternary ammonium salts include polyvinylbenzyltrimethylammonium chloride, polydiallyldimethylammonium chloride, poly-2-acryloyloxyethyltrimethylammonium chloride, butyl methacrylate-2-methacryloyloxyethyltrimethylammonium chloride copolymer, methyl methacrylate. Examples include quaternary ammonium salt-based cationic acrylic resins such as 2-methacryloyloxyethyl trimethyl ammonium chloride copolymer, and among them, methyl methacrylate / 2-methacryloyl oxyethyl trimethyl ammonium chloride copolymer has an antistatic effect and durability. It is preferable because it has good properties.

The antistatic layer is preferably formed by preparing a coating solution containing an antistatic agent, applying the coating solution on a release sheet, and drying. The amount of the antistatic agent used varies depending on the type of the antistatic agent and the purpose of use, but it is preferably 0.5 to 1.5 g / m ² , and the surface resistivity of the antistatic layer is preferably 1 0.0 x 10 ^{7 to} 1.0 x 10
¹¹ Ω / □ (20 ° C., RH 65%), more preferably 1.
0 × 10 ^{8 to} 1.0 × 10 ¹⁰ Ω / □ (20 ° C., RH65
%). If the amount used or the surface resistivity is out of the preferable range and the amount is too small in any case, the toner retransfer easily occurs, and if the amount is too large, discharge marks easily occur. This antistatic layer improves the electrostatic resistance, transportability and transfer efficiency of the image receiving sheet, suppresses the generation of discharge marks, the retransfer of toner and the generation of pseudo contours, and further reduces the stickiness of silicone oil. It is also effective.

The antistatic release layer may be a release sheet itself composed of a single layer composed of an appropriate sheet base material having a main component and an antistatic agent. The surface resistivity of this release layer is also preferably 1.0 × 10 ^{7 to} 1.0 × 10 ¹¹ Ω.
/ □ (20 ° C, RH 65%), more preferably 1.0 ×
10 ^{8 to} 1.0 × 10 ¹⁰ Ω / □ (20 ° C, RH 65%)
Is.

The color electrophotographic image-receiving sheet of the present invention may contain, if necessary, within the range not impairing the object of the present invention.
Various additive components conventionally used in color electrophotographic image-receiving sheets can be blended. Examples of the additive component include a binder resin for toner, a hydrophilic solvent for improving coatability, a surfactant, a transparent resin, an antiblocking agent, and a crosslinking agent.

Next, schematic sectional views of typical examples of the image-receiving sheet of the present invention are shown in FIGS. In the figure, 1 is a base sheet, 2 is an undercoat layer, 3 is a toner receiving layer, 4 and 5 are antistatic layers, 6 is a polyester resin as a main component, and mainly a polyester containing a roughening agent. Layer, 7 is an adhesive layer, 8 is a release sheet, 9 is a release sheet 8 and an antistatic layer 4
The antistatic release layer is composed of

Thus, in FIG. 1, the antistatic layer 4 is provided on the surface of the release sheet (on the side opposite to the surface in contact with the adhesive layer).
In addition, by providing the antistatic layer 5 on the layer 6 mainly composed of polyester resin, and in FIG. 2, the antistatic layer 4 is provided on the surface of the release sheet, and the toner receiving layer 3 containing the antistatic agent is provided. By providing the undercoat layer 2 on the surface of the base sheet 1, in any case, even when the image receiving sheet is charged with a high voltage at the time of copying, the discharging portion becomes uniform without being partially concentrated. It is possible to prevent generation of discharge marks and retransfer of toner, improve electrostatic resistance and transportability, and further reduce stickiness of silicone oil.

[0035]

The color electrophotographic image-receiving sheet of the present invention has excellent image sharpness, prevents retransfer of toner, prevents the generation of discharge marks, and is a toner such as magenta, cyan, yellow, and black toner. It has excellent adhesiveness with, has no background bleeding, does not generate pseudo contours, and has excellent blocking resistance. Further, the sheet of the present invention has the advantages of excellent color tone reproducibility, good heat resistance and dimensional stability, as well as providing an image with high saturation and moderate surface gloss. Further, there is an advantage that a copy obtained by using the sheet of the present invention can be attached to an arbitrary place.

[0036]

The present invention will be described in more detail with reference to Examples. In addition, the part in the usage-amount of each component means a weight part.

Example 1 100 μm thick foamed polyester sheet (E manufactured by Toray Industries, Inc.
-65) is used as a base sheet, and Tg is -1 on the surface.
Aqueous dispersion of polyester at 0 ° C. (manufactured by Toyobo Co., Vylonal) 68.5 parts, synthetic silica 13.6 parts, water 11.
6 parts, isopropyl alcohol 3.0 parts, dioctyl sulfosuccinic acid sodium salt (hereinafter referred to as DOSS)
A liquid having a composition of 1.5 parts and polyvinyl butyral 1.8 parts is applied and dried to form an 8 μm-thick layer mainly composed of polyester, and then a quaternary ammonium salt-based antistatic agent is formed on this layer. Agent (Mitsubishi Petrochemical Co., Saftomer CP-2
000) 5 parts, 25 parts of ethanol and 70 parts of water are applied and dried, and the amount of antistatic agent used is 0.7 g / m 2.
An antistatic layer ² was formed to provide a toner receiving layer on the surface of the base sheet.

Furthermore, a quaternary ammonium salt type antistatic agent (manufactured by Mitsubishi Petrochemical Co., Saftomer CP-2) was formed on the surface of a transparent polyester sheet having a thickness of 75 μm as a release sheet.
000) 5 parts, 25 parts of ethanol and 70 parts of water are applied and dried, and the amount of antistatic agent used is 0.7 g / m 2.
Along with forming the antistatic layer of ² , the acrylic emulsion-based adhesive is applied to the back surface of the release sheet, and then this adhesive surface is applied to the back surface of the base sheet (the surface opposite to the surface on which the toner receiving layer is provided). I stuck it. In this way, a color electrophotographic image-receiving sheet was produced. Surface resistivity (20 ° C., RH 65%) of the toner receiving layer and antistatic layer on the release sheet of this product (hereinafter referred to as surface resistivity)
Was 1.0 × 10 ¹⁰ Ω / □.

Example 2 Instead of the "aqueous dispersion of polyester having a Tg of -10 ° C", an "aqueous dispersion of polyester having a Tg of 6 ° C" was used, and the amounts of this aqueous dispersion, synthetic silica and water were adjusted. A layer containing 8 μm-thick polyester as a main layer was formed in the same manner as in Example 1 except that polyvinyl butyral was not used instead of 56.9 parts, 11.8 parts and 26.8 parts.
Then, in the same manner as in Example 1, a color electrophotographic image-receiving sheet having the same surface resistivity as in Example 1 was produced.

Comparative Example 1 An image receiving sheet for color electrophotography was produced in the same manner as in Example 1 except that the antistatic layer was not provided on the surface of the release sheet. The surface resistivity of this product is shown in Table 1.

Comparative Example 2 A color electrophotographic image-receiving sheet was prepared in the same manner as in Example 1 except that the toner receiving layer was not provided with an antistatic layer. The surface resistivity of this product is shown in Table 1.

Comparative Example 3 Color electrophotography was carried out in the same manner as in Example 1 except that "aqueous polyester dispersion having Tg of 67 ° C" was used in place of "aqueous polyester dispersion having Tg of -10 ° C". An image receiving sheet for use was prepared. The surface resistivity of this product is shown in Table 1.

Comparative Example 4 Color electrophotography was carried out in the same manner as in Example 1 except that "aqueous dispersion of polyester having Tg of -40 ° C" was used in place of "aqueous dispersion of polyester having Tg of -10 ° C". An image receiving sheet for use was prepared. The surface resistivity of this product is shown in Table 1.

Comparative Example 5 of the antistatic agent used in the antistatic layer in the toner receiving layer
Use amount 0.4g / m ^TwoSame as Example 1 except that
Then, a color electrophotographic image-receiving sheet was produced. This one
Table 1 shows the surface resistivity.

Comparative Example 6 A color electrophotographic image receiving sheet was prepared in the same manner as in Example 1 except that the antistatic layer was not provided in the toner receiving layer and on the surface of the release sheet. The surface resistivity of this product is shown in Table 1.

Comparative Example 7 of the antistatic agent used in the antistatic layer in the toner receiving layer
Use amount 1.7g / m ^TwoSame as Example 1 except that
Then, a color electrophotographic image-receiving sheet was produced. This one
Table 1 shows the surface resistivity.

Comparative Example 8 Example 1 except that the surface roughening agent synthetic silica was not included.
An image-receiving sheet for color electrophotography was produced in the same manner as in.
The surface resistivity of this product is shown in Table 1.

[0048]

[Table 1]

Example 3 100 μm thick foamed polyester sheet (E, manufactured by Toray Industries, Inc.)
-65) is used as a base sheet, and Tg is 4 ° C. on the surface.
0.8 parts by weight of saturated polyethylene terephthalate, 0.3 parts by weight of benzoguanamine resin fine particles (average particle size 2 μm) and quaternary ammonium salt-based cationic acrylic resin antistatic agent (Hamacoat ES-, manufactured by Misawa Ceramic Chemical Co., Ltd.). 150) 1.1 parts by weight, 41.0 parts by weight of methyl ethyl ketone, 39.3 parts by weight of toluene and 17.5 parts by weight of methyl cellosolve acetate are applied and dried to form a toner receiving layer having a thickness of 8 μm. did.

Further, on the surface of a transparent polyester sheet having a thickness of 75 μm as a release sheet, 5% by weight of a quaternary ammonium salt type cationic acrylic resin antistatic agent (Hamacoat ES-150 manufactured by Misawa Ceramic Chemical Co.) was added. A liquid containing 25% by weight of methyl cellosolve and 70% by weight of water is applied and dried to reduce the amount of the antistatic agent used to 0.7.
While forming an antistatic layer of g / m ^2, an acrylic emulsion-based adhesive is applied to the back surface of the release sheet, and this adhesive surface is then applied to the back surface of the base sheet (on the side opposite to the surface on which the toner receiving layer is provided). Pasted on the surface). In this way, a color electrophotographic image-receiving sheet was produced. The surface resistivity (20 ° C., RH 65%) (hereinafter referred to as surface resistivity) of the toner receiving layer and the antistatic layer on the release sheet of this product was 1.0 × 10 ¹⁰ Ω / □.

Example 4 A color electrophotographic image-receiving sheet was prepared in the same manner as in Example 3 except that the saturated polyethylene terephthalate was changed to Tg = 11 ° C. The surface resistivity of this product is shown in Table 2.

Comparative Example 9 A color electrophotographic image-receiving sheet was produced in the same manner as in Example 3 except that the antistatic layer was not provided on the surface of the release sheet. The surface resistivity of this product is shown in Table 2.

Comparative Example 10 A color electrophotographic image-receiving sheet was prepared in the same manner as in Example 3 except that the toner receiving layer did not contain an antistatic agent. The surface resistivity of this product is shown in Table 2.

Comparative Example 11 Color electrophotography was carried out in the same manner as in Example 3 except that "aqueous polyester dispersion having Tg of 67 ° C" was used in place of "aqueous polyester dispersion having Tg of -10 ° C". An image receiving sheet for use was prepared. The surface resistivity of this product is shown in Table 2.

Comparative Example 12 Color electrophotography was carried out in the same manner as in Example 3 except that "aqueous polyester dispersion having Tg of -10 ° C" was replaced with "aqueous polyester dispersion having Tg of 40 ° C". An image receiving sheet for use was prepared. The surface resistivity of this product is shown in Table 2.

Comparative Example 13 The amount of the antistatic agent contained in the toner receiving layer was adjusted to 0.
A color electrophotographic image-receiving sheet was produced in the same manner as in Example 3 except that the amount was 01 g / m ² . The surface resistivity of this product is shown in Table 2.

Comparative Example 14 A color electrophotographic image-receiving sheet was prepared in the same manner as in Example 3 except that the toner receiving layer did not contain an antistatic agent and the release sheet surface was not provided with an antistatic layer. The surface resistivity of this product is shown in Table 2.

Comparative Example 15 The amount of the antistatic agent contained in the toner receiving layer was 1.
A color electrophotographic image-receiving sheet was produced in the same manner as in Example 3 except that the amount was 7 g / m ² . The surface resistivity of this product is shown in Table 2.

Comparative Example 16 A color electrophotographic image-receiving sheet was prepared in the same manner as in Example 3 except that the surface-roughening agent benzoguanamine resin was not contained. The surface resistivity of this product is shown in Table 2.

[0060]

[Table 2]

With respect to the image-receiving sheets of Examples and Comparative Examples, toner images were formed using a commercially available color copying machine (PIXEL EPO manufactured by Canon Inc.) under the conditions of 25 ° C. and RH of 30%, and a copying test was conducted. The test results are shown in Tables 3 and 4.

Evaluation of the test results is as follows. (1) Image sharpness: visually observed. ○: It is clear. Δ: There is partial unevenness. X: There is unevenness more than half.

(2) Generation of pseudo contour: It was visually observed. ◯: Does not occur. Δ: Some occurrence. X: Occurred partially.

(3) Generation of discharge mark: A patch in which the input dot area ratio was continuously changed was copied, and the image was visually observed. ◯: Does not occur. Δ: Some occurrence. X: Occurred partially.

(4) Occurrence of retransfer: A patch in which the input dot area ratio was continuously changed was copied, and the image was visually observed. ◯: Does not occur. X: Occurred partially.

(5) Transportability: 1 test sheet in the cassette
0 sheets were set, continuously conveyed, and the degree of double feeding was visually observed. ○: No double feeding. Δ: 1 to 2 sheets were multi-fed. X: 5 or more sheets are multi-fed.

(6) Toner adhesion: After attaching a commercially available adhesive tape to the toner image, the degree of peeling by rubbing by hand was visually observed. ◯: Does not peel. Δ: 1/5 peeled. X: 2/5 peeled.

(7) Stickiness of silicone oil: The test sheet after copying was evaluated by touch. ◯: No stickiness at all. Δ: A little sticky is felt. X: Feels sticky.

(8) Anti-blocking property: Two image-receiving sheets were superposed with their antistatic layer surfaces on the toner-receiving layer side in contact with each other, and 10 kg load / 100 cm ² (50
A force of (° C., RH 80%) was applied to the image receiving sheet, and after 24 hours, the two image receiving sheets were peeled by hand, and the state was visually observed. ◯: No blocking occurs. Δ: Blocking partially occurs. X: Blocking occurs on the entire surface.

[0070]

[Table 3]

[0071]

[Table 4]

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an example of a color electrophotographic image-receiving sheet of the present invention.

FIG. 2 is a schematic sectional view of another example of the color electrophotographic image-receiving sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base sheet 2 Undercoat layer 3 Toner receiving layer 4,5 Antistatic layer 6 Layer mainly made of polyester resin 7 Adhesive layer 8 Release sheet 9 Antistatic release layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Yamada 4-11-2 Ginza, Chuo-ku, Tokyo Somer Co., Ltd.

Claims (4)

[Claims] 1. A color electrophotographic image-receiving sheet in which a toner-receiving layer is provided on the surface of a base sheet directly or via an undercoat layer, wherein (A) a polyester resin having a glass transition temperature of 30 ° C. or lower as the toner-receiving layer. , (B) roughening agent and (C) at least an antistatic agent, and
A color having a surface resistivity of 10 ⁷ to 10 ¹¹ Ω / □ (20 ° C., RH 65%) and an antistatic release layer provided on the back surface of the base sheet via an adhesive layer. Image receiving sheet for electrophotography. 2. The toner receiving layer is a single layer containing at least (A) a polyester resin having a glass transition temperature of 30 ° C. or lower, (B) a surface-roughening agent and (C) an antistatic agent. Image receiving sheet for color electrophotography. 3. A toner-receiving layer comprising (A) a layer containing at least a polyester resin having a glass transition temperature of 30 ° C. or lower, (B) a surface-roughening agent, and (C) a layer containing at least an antistatic agent. The image-receiving sheet for color electrophotography according to claim 1, which comprises: 4. The color electrophotographic image-receiving sheet according to claim 1, wherein the antistatic release layer is a release sheet having an antistatic layer provided on the surface thereof.