JP2788358B2 - Transfer film for electrophotography and color image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic transfer film for carrying a color toner image formed by electrophotography, and a color image for forming a color image on the electrophotographic transfer film. It relates to a forming method.

[0002]

2. Description of the Related Art In recent years, it has been widely practiced to form a full-color image on a transparent film by an electrophotographic method and to provide a transparent film having a toner image to an OHP for use as a projected image. In the conventional electrophotographic system, since the refraction of incident light generated at the boundary surface between the toner and the air is large, only a dark projected image with low chroma can be obtained. In order to solve this problem, it is necessary to reduce the unevenness of the toner image formed on the transparent film.
Although various methods have been proposed as described below, the above problems could not be completely solved.

For example, Japanese Patent Application Laid-Open No. Sho 59-184361 proposes a method of spray-coating a lacquer or the like on a toner image surface. Problems such as contamination of the image portion occur. Japanese Patent Application Laid-Open No. 60-52861 proposes a method of coating a toner image with a laminating film.
JP-A-36762 proposes a method in which a transparent film is superimposed on a toner image and heat roll-fixed, and then the transparent film is peeled off. However, these methods have problems such as an increase in the number of processing steps after image formation, and destruction of the toner image when the transparent film is peeled off.

Japanese Patent Application Laid-Open No. 63-80273 discloses a method for fixing a toner at a temperature at which the toner is sufficiently dissolved, a method for fixing using a solvent such as toluene, a method for polishing a fixed image surface, and a method for dissolving a toner. A method of applying a transparent paint to the toner image after fixing has been proposed.However, in the case of a roller fixing method at a high temperature, an attempt to reduce unevenness of a toner-less portion such as a halftone portion reduces the amount of toner. will be offset occurs in large part, that in a non-contact heat fixing device as an oven results in a ripple on the transparent Fi le-time, considerable fixing time is required to obtain a and sufficient translucency There are drawbacks. In the case of the method using a solvent, there is a drawback that when the fluidity of the toner is increased by the solvent until the unevenness of the toner in the halftone portion is reduced, the image is distorted and the flow occurs in the high density portion. In the case of the method of polishing an image, the light transmittance is increased in a portion having a relatively large amount of nato, but there is a disadvantage that the unevenness of the toner cannot be sufficiently reduced in a low density region. Further, in the case of a method of applying a transparent paint that does not dissolve the toner on the toner image, a clear boundary may be formed on the toner image with the toner particles, the incident light is scattered at this boundary surface, and the saturation is low. There is a disadvantage that a dark projected image is obtained.

[0005] Japanese Patent Application Laid-Open No. Hei 2-263624 discloses a method for reducing the unevenness of a toner image formed on a transparent film, which is compatible with a toner binder resin and has a lower temperature than a toner binder resin at a toner fixing temperature. Also, a method has been proposed in which a transparent resin layer having a large storage modulus is provided on a transparent film. However, in the case of this method, since the storage elastic modulus of the transparent resin layer is larger than that of the toner binder resin, the toner hardly sinks into the transparent resin layer, or the toner hardly diffuses in the lateral direction, and the toner image is hardly formed. In order to reduce unevenness, it is necessary to make the transparent resin layer thick enough and force the toner to sink by high pressure using a heat roller with high hardness, and make the transparent resin layer too thick This causes problems such as image blur, distortion, and image cracking due to bending, wrinkles during fixing due to high-pressure fixing with a high-hardness heat roll, and an increase in curl after fixing.

Further, when a color image is formed digitally, the density of each color is changed by changing the area of minute dots or lines. The fixing device makes the halftone part sufficiently smooth, but the halftone part has large irregularities due to the image structure of dots and lines and does not become sufficiently smooth, so the incident light is refracted and the halftone part of the projected image becomes saturated. When a natural image such as a photograph is reproduced due to a darkened image having a low density, a shadow (hereinafter, referred to as a “pseudo-contour”) that is not included in the original in the halftone portion is likely to occur.

[0007] In order to improve the false contour that is likely to occur when a digital color image is formed, it is necessary to sufficiently sink the toner image into the transparent resin layer on the transparent film or to diffuse the toner image in the lateral direction. 2-2.
In the case of using a method proposed in US Pat. No. 63,642, that is, using a transparent film coated with a transparent resin having a higher storage elastic modulus than the toner binder resin, the toner image hardly sinks into the transparent resin layer, or Since the toner image is hardly diffused in the horizontal direction, the unevenness of the toner image in the halftone portion cannot be sufficiently reduced, and therefore, it is difficult to prevent the occurrence of the false contour.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems in the prior art, and it is possible to obtain a high saturation by a simple method as compared with the prior art. Provided is an electrophotographic transfer film capable of obtaining a color projection image which is bright, has good color tone reproducibility, and has no false contour, and a method for forming a good color image on the transfer film. Is to do.

That is, one of the objects of the present invention is to provide a transfer film for electrophotography capable of forming a good full-color projected image. Another object of the present invention is to provide a transfer film for electrophotography capable of forming a full-color projected image having high lightness and saturation. Another object of the present invention is to provide an electrophotographic transfer film excellent in reproducibility of a full-color image. Another object of the present invention is to provide a transfer film for electrophotography which improves a false contour which is likely to occur when a digital color image is formed. Another object of the present invention is to provide an electrophotographic transfer film having excellent fixability of a full-color toner image. Still another object of the present invention is to provide a color image forming method for forming a good full-color projected image on an electrophotographic transfer film by a simple method.

[0010]

Means for Solving the Problems The inventors of the present invention improved the chroma, lightness, color tone reproducibility, fixing degree and pseudo contour of a color projected image by examining the constitution of a coating layer of an electrophotographic transfer film, the resin, and the like. As a result of studying the characteristics of
Provide an intermediate adhesive layer on a plastic film of
In addition, at the fixing temperature of the toner used for color image formation, a specific polyester having compatibility with the toner binder resin and having a lower viscosity at the fixing temperature than the binder resin.
The present inventors have found that the above problems can be greatly improved by using an electrophotographic transfer film provided with a transparent resin layer made of a resin, and have completed the present invention.

In the transfer film for electrophotography according to the present invention, an intermediate adhesive layer is provided on at least one surface of a plastic film having a heat resistance temperature of 100 ° C. or higher, and a toner to be fixed at a toner fixing temperature is formed thereon. There is a binder resin and compatibility, the fixing temperature of the toner, than the binder resin of the toner rather low apparent melt viscosity, and the following formula (I)
The bisphenol derivative represented by the diol component,
Divalent or higher carboxylic acid or its anhydride or its low
Containing a lower alkyl ester as a carboxylic acid component
A transparent resin layer formed of a ester resin is provided, and is suitable for color image projection.

Embedded image Wherein R is an ethylene or propylene group, x and y are
Each is a positive integer of 1 or more, and the average value of x + y is
2-10. In another transfer film for electrophotography according to the present invention, an intermediate adhesive layer is provided on at least one surface of a plastic film having a heat-resistant temperature of 100 ° C. or higher, and a fusion with a toner to be fixed at a fixing temperature. toner tilt angle of 40 degrees or less, and apparent melt viscosity at a temperature 100 ° C. is 1 × 10 ³ ~7 × 10 ⁴ poises the
A transparent resin layer formed of a polyester resin is provided, and is suitable for color image projection. In addition, the color image forming method of the present invention forms a color toner image formed from a toner containing at least a colorant and a binder resin on each of the above electrophotographic transfer films by heat and pressure. Is fixed by providing

When the above-mentioned electrophotographic transfer film of the present invention is used, when the color toner image formed thereon is fixed by a fixing means such as a heat roll, the fixed toner image is formed together with the transparent resin layer on the plastic. The film is not easily separated from the film, and the decrease in the fixing degree is improved.

Hereinafter, the present invention will be described in more detail with reference to the drawings. 1 and 2 illustrate an electrophotographic transfer film according to the present invention. In the figure, 101 is a plastic film, 102 is a transparent resin layer , 103 is
It is an intermediate adhesive layer . In FIG. 1, an antistatic layer 104 is provided on the side opposite to the transparent resin layer side of the plastic film.

In the electrophotographic transfer film of the present invention, as the plastic film 101, specifically, a polyethylene terephthalate film having a heat resistant temperature of 100 ° C. or higher, a polysulfone film, a polyphenylene oxide film, a polyimide film, a polycarbonate film, Examples include a cellulose ester film and a polyamide film. Among them, a polyethylene terephthalate film is particularly preferred in terms of heat resistance and transparency. The heat resistance temperature of plastic film is 100 ℃
If the value is less than the above range, the toner is deformed when thermally fixed, and cannot be used. Further, the thickness of the plastic film is required to be such that no wrinkles are generated when the film is softened by heating at the time of heat fixing, and is generally required to be 50 μm or more, preferably 75 μm or more. The upper limit of the thickness of the plastic film is 200 μm or less, preferably 150 μm or less, in consideration of a decrease in light transmittance. Therefore, the thickness of the heat-resistant plastic film may be set in the range of 50 to 200 μm, preferably 75 to 150 μm.

The transparent resin layer 102 is a transparent resin layer that improves the saturation, lightness, and color tone reproducibility of a color image after fixing, and prevents the occurrence of false contours. The transparent resin layer can be compatible with the binder resin of the toner for forming a color image at the temperature at the time of heat fixing, and at the fixing temperature of the toner, in order to sufficiently sink the toner at the time of heat fixing. ,
It is necessary that the apparent melt viscosity is lower than that of the binder resin of the toner. When the apparent melt viscosity of the resin of the transparent resin layer 102 is larger than the apparent melt viscosity of the binder resin of the toner, when the toner image formed on the transparent resin layer is heated and fixed by pressure with a heat roll, the toner Unable to sufficiently sink into the transparent resin layer, the unevenness of the toner image remains,
The saturation of the projected image is reduced, and a pseudo contour occurs.

[0016]

[0017]

Being compatible with the binder resin of the toner means that the resin of the transparent resin layer 102 and the binder resin of the toner do not form a boundary in the image after fixing. As a method for evaluating the compatibility of the toner with the binder resin, a solubility parameter is used in Japanese Patent Application Laid-Open No. Hei 2-263624, but the method for evaluating the compatibility during heat fixing is as follows. However, it has become clear from studies by the inventors that this is not always preferable. As a method for correctly evaluating the compatibility of a toner with a binder resin, the present inventors have found a new evaluation scale called “molten toner inclination angle”. The method for measuring the “melt toner inclination angle” will be described below.

(Measurement Method of Tilt Angle of Fused Toner) A toner disk is formed. Hand press SSP for tablet press manufactured by Shimadzu Corporation
A 10-shaped tablet frame having a concave shape with a diameter of 13 mm and a height of 33 mm (see FIG. 4 ) is filled with powdered toner, and a 1-ton weight is applied by a hand press for 1 minute to form a toner disk. At this time, the standard size of the toner disk is 13 mm in diameter, 1.2 mm in thickness, and 0.183 g in weight. (See Fig. 5 )

Melt Solidification of Toner A transfer target film and a toner disk set at a set temperature are placed as shown in FIG. 6 , and the toner disk is melted for 1 minute (for example, when the fixing roll is at 150 ° C. When the temperature of the transfer film transparent resin layer is 100 ° C.,
Measure at 100 ° C. ). FIG. 6 illustrates such a case, and shows a state where the transfer target film 62 and the toner disk 61 are mounted on the hot plate 63. Thereafter, the plate is placed on an aluminum plate having a thickness of 5 mm and a size of 420 mm × 297 mm for 1 minute, rapidly cooled and solidified.

Measurement of Melt Toner Tilting Angle Using a contact angle measuring device manufactured by Kyowa Interface Chemical Co., Ltd., the angle of the foot of the toner after the toner is solidified is measured twice, and the average value is used as the average value of the melting toner tilt angle. And

From the viewpoint of the angle of inclination of the molten toner, the transparent resin layer 1
When selecting the resin No. 02, it is preferable to use a resin having a toner inclination angle of 40 degrees or less between the toner used for color image formation and the transparent resin layer. Examples of the resin of the transparent resin layer in which the melt toner inclination angle is 40 degrees or less include, in addition to the above-described polyester resin comprising a bisphenol derivative or a substituted product thereof and a divalent or higher carboxylic acid, a polyester resin, a styrene-acryl ester resin. ,Epoxy resin,
Thermoplastic resins such as polyurethane resins, polymethyl methacrylate resins, vinyl chloride resins, and vinyl chloride-vinyl acetate copolymers can be used. Particularly preferred is a resin of the same type as the main resin of the toner (a resin contained at 50% by weight or more based on the binder resin). That is, when the main resin of the toner is a polyester resin, a polyester resin is used as the resin of the transparent resin layer. When the main resin of the toner is a styrene-acryl ester resin, a styrene-acryl ester resin is used as the resin of the transparent resin layer. preferable.

The important characteristics of the resin of the transparent resin layer 102 are that the inclination angle of the molten toner is not more than 40 degrees and the apparent melt viscosity at the fixing temperature is lower than that of the binder resin of the toner. . The apparent melt viscosity is
It is determined as follows. That is, a flow tester CFT-500A manufactured by Shimadzu Corporation was used, and the diameter of the die (nozzle) was 0.5 mm and the thickness was 1.0 mm.
After applying an extrusion load of kg, an initial set temperature of 80 ° C., a preheating time of 300 seconds, and an apparent melt viscosity at each temperature when the temperature was raised at a constant speed of 5 ° C./min were measured. The apparent melt viscosity at the fixing temperature of the transparent resin layer 102 is defined as the apparent melt viscosity at the fixing temperature.
(For example, when the fixing roll is at 150 ° C. and the surface temperature of the transferred film is fixed at 100 ° C., the apparent melt viscosity at 100 ° C. is defined as the apparent melt viscosity at the fixing temperature.)

The apparent melt viscosity at a fixing temperature of 100 ° C. required for the resin of the transparent resin layer 102 depends on the melt viscosity of the toner to be used. × 10 ³
７7 × 10 ⁴ poise, preferably 5 × 10 ³ to 4 × 10
Those having ⁴ poises are used. Transparent resin layer 102
When a resin having an apparent melting temperature of less than 1 × 10 ³ poise at a temperature of 100 ° C. is used as the resin of the transparent resin layer 102 when the toner image is fixed by a heat roll,
Is undesirably peeled off from the plastic film. On the other hand, as the resin of the transparent resin layer 102, a temperature of 100
When a resin having an apparent melt viscosity at 7 ° C. of more than 7 × 10 ⁴ poises is used, the degree of sinking of the toner image into the transparent resin layer is extremely small even when the toner image is fixed with a heat roll, and the projected image is colored. The degree is low and false contours occur. The optimum thickness of the transparent resin layer 102 depends on the particle size of the toner to be fixed, but when the color image forming method of the present invention is adopted, the thickness is preferably in the range of 1 to 8 μm.

In the electrophotographic transfer film of the present invention, the plastic film 101 and the transparent resin layer 102
Between them, an intermediate adhesive layer 103 is provided. Intermediate adhesive layer 10
No. 3 acts to improve the adhesion between the plastic film and the transparent resin layer and prevent the toner image fixed after fixing from peeling off the plastic film together with the transparent resin layer.
I do.

The intermediate adhesive layer is made of a plastic film 10
1 and the transparent resin layer 102 are compatible with each other, have high heat resistance, and are made of a resin that is not melted by heating during fixing.
As a resin that can be used for the intermediate adhesive layer, a polyester resin, an acrylate resin, a methacrylate resin, a styrene-acrylate copolymer,
Resins such as styrene-methacrylic acid ester copolymers are exemplified. The intermediate adhesive layer needs to have a certain thickness or more in order to secure the adhesiveness between the transparent resin layer and the plastic film.
In this case, the thickness of the intermediate adhesive layer is preferably in the range of 0.05 to 0.5 μm because the effect of sinking the toner is reduced. In the present invention, when the transparent resin layer 102 is provided on one surface of the plastic film, it is preferable to provide the other surface with the layer 104 that imparts slipperiness.

Next, a method for producing the electrophotographic transfer film of the present invention will be described. Alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, methylene chloride, ethylene chloride,
A resin for forming the transparent resin layer 102 is dissolved in one or a mixture of two or more chlorinated hydrocarbons such as tetrachloroethane, and a bar coating method, a dip method,
It is applied on the intermediate adhesive layer provided on the plastic film 101 by an application method such as a spray method or a spin coating method, and dried.

Further, the transparent resin layer 102 may contain a matting agent for adjusting a friction coefficient between films or an antistatic agent for preventing triboelectric charging, if necessary. Examples of the matting agent include fine particles such as silica, starch, and alumina, and plastic powders such as polyethylene, polyester, polyacrylonitrile, and polymethyl methacrylate. The amount of the matting agent used is preferably in the range of 0.1% by weight to 10% by weight based on the resin used.
Examples of the antistatic agent include an alkylbenzimidazole sulfonate, a naphthalene sulfonate, a carboxylate sulfonate, a phosphate and the like. The intermediate bonding layer 10 3 can be formed using the same solvent and coating method as in the case of forming the transparent resin layer.

Next, the toner used in the color image forming method of the present invention will be described. A toner used in a color electrophotographic apparatus needs to have good meltability and color mixing when heat is applied, and has a low softening point, a low apparent melt viscosity at a fixing temperature, and a sharp melt toner. It is preferred to use. In relation to the transparent resin layer 102 of the electrophotographic transfer film described above, the binder resin of the toner has an apparent melt viscosity more clearly than the apparent melt viscosity of the resin forming the transparent resin layer. Larger is preferred. Specifically, the binder resin of the toner has an apparent melt viscosity of 8 × 10 ^{4 to} 3 × at a temperature of 100 ° C.
It is preferably 10 ⁵ poise, and more preferably 9 × 10 ⁴ to 2 × 10 ⁵ poise, in view of compatibility with the electrophotographic transfer film and color mixing between toners.

The toner is manufactured by melt-kneading, pulverizing and classifying a binder resin such as a polyester resin or a styrene-acryl ester resin, a colorant (dye, a sublimable dye), and a toner-forming material before charge control. Is done. If necessary, an external addition step of adding various external additives (for example, hydrophobic colloidal silica) to the toner may be added.

In consideration of the fixability and the sharp-melt property, the color toner is prepared by using, as a binder resin, a bisphenol derivative represented by the above formula (I) or its substituted product of the same type as the resin in the transparent resin layer as a diol. Ingredients
A polyester resin containing at least a carboxylic acid component comprising a divalent or higher carboxylic acid or an acid anhydride thereof or a lower alkyl ester thereof is preferred. The softening point of the polyester resin is 75 to 150 ° C, preferably 80 to
A range of 120 ° C. is preferred. In relation to the toner and the electrophotographic transfer film, the temperature of the binder resin of the toner 1
The apparent melt viscosity at 00 ° C. is 100 ° C. of the resin used for the transparent resin layer 102 of the film to be transferred.
The binder resin is selected and used so as to be clearly larger than the apparent melt viscosity in the above.

Next, a color image forming method will be described. FIG. 3 is a schematic sectional view of an electrophotographic apparatus capable of forming a full-color image used in the present invention. The electrophotographic apparatus includes a transfer material transport system provided from a lower side of the apparatus main body (lower side in FIG. 3 ) to a substantially central portion of the apparatus main body, and a transfer material transport system provided at a substantially central portion of the apparatus main body. The latent image forming unit is provided in the vicinity of the transfer drum 10 and the developing device is provided in the vicinity of the latent image forming unit.

The transfer material transport system includes supply trays 15 and 16 formed on the lower side of the apparatus main body, and paper feed rollers 17 and 1 disposed almost directly above the respective trays.
8, paper feed guides 19 and 20 disposed close to these paper feed rollers, and a transfer material separation charger 21 provided near the paper feed guide 20 and near the outer peripheral surface. And the transfer device 11 and the electrode 2
A transfer drum 10 on which a transfer roller 4 is disposed and is rotatable in the direction of the arrow.
And a contact roller 23 in contact with the outer peripheral surface thereof, a conveying device 13, a fixing device 14 disposed close to the end of the conveying device in the conveying direction, and a detachable discharge tray 2.
And 2.

The outer peripheral surface of the latent image forming section is
An electrostatic latent image holding member (photosensitive drum) 1 which is disposed in contact with the outer peripheral surface of the photosensitive drum 0 and is rotatable in the direction of an arrow;
A charger 8 disposed near the outer peripheral surface of the electrostatic latent image carrier; and an image exposure device such as a laser beam scanner for forming an electrostatic latent image on the outer peripheral surface of the electrostatic latent image carrier. A writing device 9 having a means and an image exposure / reflection means such as a polygon mirror; and a cleaning device 12.

The developing device comprises a developer carrier 7 and a housing 6, and is formed on the outer peripheral surface of the electrostatic latent image carrier at a position facing the outer peripheral surface of the electrostatic latent image carrier 1. Black developing machine 2, magenta developing machine 3, cyan developing machine 4 for visualizing (ie, developing) the formed electrostatic latent image
And a yellow developing machine 5.

The sequence of image formation by the electrophotographic apparatus having the above configuration will be described by taking a full color mode as an example. When the electrostatic latent image carrier 1 described above rotates in the direction of the arrow, the surface of the electrostatic latent image carrier is charged by the charger 8.
Is charged uniformly. When uniform charging is performed by the charger 8, an electrostatic latent image is formed on the electrostatic latent image holder 1 through the writing device 9 by a laser beam modulated by a black image signal of a document (not shown). Then, the electrostatic latent image is developed by the black developing machine 2. On the other hand, from the supply tray 15 or 16 to the paper feed roller 17 or 1
8. The transfer material conveyed via the paper feed guide 19 or 20 is applied to the electrode 2 facing the contact roller 23.
4 electrostatically winds the transfer drum 10.
The transfer drum 10 rotates in the direction of the arrow in synchronization with the electrostatic latent image holder 1, and the developed image developed by the black developing device 2 is transferred to the outer peripheral surface of the electrostatic latent image holder 1 and the transfer drum 10. The image is transferred by the transfer device 11 at a portion where the outer peripheral surface is in contact. The transfer drum 10 continues to rotate as it is to prepare for the transfer of the next color (magenta in FIG. 3 ).

On the other hand, the electrostatic latent image holder 1 is neutralized by a neutralizing charger (not shown), cleaned by a cleaning device 12, and then charged again by the charger 8 to form a next magenta image. The signal is subjected to image exposure as described above. The electrostatic latent image formed by image exposure according to the magenta image signal is developed by the magenta developing machine 3 to become a visible image. Subsequently, the above-described process was performed for cyan and yellow, respectively,
When the transfer of the colors is completed, the multicolored visible image formed on the transfer material is neutralized by the charger 21 and sent to the fixing device 14 by the paper conveying device 13 and is fixed by heat and pressure to form a series of full-color images. The formation sequence ends.

The main part of the fixing device 14 is composed of a heat roll 14a and a pressure roll 14b having the same structure. The heat roll 14a has 50 inside.
A substrate roll provided with a 0 W Colts lamp and formed of a steel core material having an outer diameter of 44 mmφ, and a rubber hardness provided on the substrate roll via an appropriate primer according to JIS.
It is composed of a fluorine-based rubber (for example, Viton rubber manufactured by DuPont) having a hardness of 60 ° and a thickness of 40 μm. On the other hand, the pressure roll has the same configuration, and uses a substrate roll formed of a steel core material having an outer diameter of 48 mmφ and an inner elastic layer having a thickness of 1 mm made of silicon rubber provided on the substrate roll. Except for, the configuration is exactly the same.

The heat roll is supplied with a release agent comprising a dimethylpolysiloxane containing a functional group (for example, an amino group) in order to modify the surface of the fluoro rubber into a high release surface. As a means, an oil donor roll made of silicone rubber is in contact. The oil donor roll is supplied with a release agent by an oil pickup roll immersed in an oil pan. The heat roll 14a and the pressure roll 14b are pressed against each other by a pressurizing mechanism, and 6 m at the center.
A nip width of m is formed. Further, both rolls are configured such that the surface temperature is set to 150 ° C. and the surfaces rotate at a speed of 60 mm / sec in the direction of the arrow.

[0040]

EXAMPLE 1 A 100 .mu.m thick polyester film having a heat distortion temperature of 152.degree. C. and a maximum operating temperature of 150.degree.
Intermediate adhesive layers of 01, 0.05, 0.5, and 1.0 μm were provided. A solution obtained by dissolving a polyester resin A having an apparent melt viscosity of 5 × 10 ³ poise in methyl ethyl ketone at 100 ° C. was applied thereon by a bar coater method, and a transparent resin comprising the polyester resin A , a matting agent, and an antistatic agent was applied. The layer was formed so as to have a thickness of 2 μm after drying, and a transfer film FA for electrophotography was obtained. For the intermediate adhesive layer, a polyester resin composed of a copolymer of terephthalic acid, isophthalic acid, neopentyl glycol and ethylene glycol was used. 10% by weight of parachlorophenol was added as a swelling agent for the polyester film, and methyl ethyl ketone was applied as a solvent. The polyester resin A has a structural unit of bisphenol
A 25% by weight, isopropylene glycol 53% by weight
And 22% by weight of fumaric acid, in the above formula (I)
It is a copolymer having the diol component shown . Also,
As a matting agent, 1% by weight of polymethyl methacrylate was added to the polyester resin. Further, an alkyl phosphate surfactant was added as an antistatic agent in an amount of 0.5% by weight based on the polyester resin.

The apparent melt viscosity at 100 ° C. is 1 ×
A cyan toner was prepared by adding 1 part by weight of a charge control agent and 3 parts by weight of a cyan pigment to 96 parts by weight of a 10 ⁵ poise polyester resin PT (solubility parameter: about 11). Similarly to the cyan toner, 96 parts by weight of the polyester resin and 3 parts by weight of the magenta pigment are added to 1 part by weight of the charge control agent to obtain the magenta toner, 3 parts by weight of the yellow pigment are added to obtain the yellow toner, and 3 parts by weight of the black pigment are added. In addition, a black toner was prepared. The volume average particle diameter of these cyan, magenta, yellow and black toners was 7 μm. The measurement of the volume average particle size of the toner is performed using a Coulter Counter T
Using a type A-II (manufactured by Coulter Inc.), the particle size distribution of particles having a particle size of 2 to 50 μm was measured using an aperture of 100 μm to determine the volume average particle size.

Using the electrophotographic transfer film obtained by the above method and the color toner, the electrophotographic apparatus shown in FIG. 3 is used to superimpose four colors of cyan, magenta, yellow and black on the transfer film. The toner weight is 2
mg / cm ² of a full-color unfixed toner image was formed.
This full-color unfixed toner image is heated and pressed and fixed under the conditions of a heat-fixing roll temperature of 150 ° C. and an average heating time of 100 msec to form a full-color fixed image on a transfer-receiving film. The contour was evaluated. At the same time, the degree of fixation of the full-color toner (including a decrease in the degree of fixation due to peeling of the transparent resin layer from the plastic film) was also evaluated.

The evaluation of the lightness and the saturation of the OHP projection image is based on the tristimulus values X of the projected colors based on JIS Z8722.
Y and Z are converted to CIE1976 (L ^* a ^* b ^* ) color space, and lightness (L ^* ) and saturation

(Equation 1) Was evaluated. The measurement of spectral transmittance uses a spectrophotometer,
The light source used was a standard light A, and the color matching function used a value of a 2-degree visual field. The evaluation of the lightness L ^* and the saturation C ^* is based on the input halftone area ratio of 10
Patches of 0% (CiN 100%) and 50% (CiN 50%) were output, and L ^* and C ^* of the translucent colors were measured.
(Evaluation was also performed for other colors, but similar results were obtained, so only the cyan result is shown.)
When a natural image of a person or the like was created on an HP film and the image was projected on a screen using an OHP, the degree of a pseudo contour generated in the image was visually evaluated.

The fixing degree was evaluated by the following method. Using a cloth or the like, cleanly remove the fuser oil adhering to the transfer-receiving film on which the color image has been fixed. Cellophane tape (Nichiban CT-18) on the fixed image
Paste. Peel off the cellophane tape. (Peel angle: 180 degrees,
Peeling time: 1 sec) The peeling state of the image area after the peeling of the cellophane tape is visually evaluated. Table 1 shows the evaluation results.

[0045]

[Table 1]

Notes: 1) Grade of pseudo contour: 1... No occurrence. 2: Almost no occurrence. 3
... acceptable level. 4: It has occurred considerably. 5: Very many occurrences. 2) Grade of fixing degree: 1 ... No peeling of image. 2: Almost no peeling. 3 ...
Acceptable level. 4: It peels off considerably. 5: Very much peeling. 3) Grade of peeling of transparent resin layer due to film bending 1: No transparent resin layer peeling. 2: Almost no peeling. 3: Acceptable level. 4: It peels off considerably. 5: Very much peeling.

As can be seen from Table 1 , the transfer film provided with the intermediate adhesive layer of 0.05 to 0.5 μm has a high degree of fixation and a transparent resin due to film bending without causing an increase in pseudo contour and a decrease in lightness and chroma. It can be understood that the peeling of the layer can be improved. If the thickness of the intermediate adhesive layer is less than 0.05 μm, the fixing degree and the effect of improving the peeling of the transparent resin layer are not sufficient. If the thickness of the intermediate adhesive layer is more than 0.5 μm, the fixing degree and the transparent resin layer Is improved, but the number of false contours increases, and the brightness and saturation also decrease. Therefore, the thickness of the intermediate adhesive layer is preferably in the range of 0.05 to 0.5 μm.

COMPARATIVE EXAMPLE 100 ° C. on a polyester film having a heat distortion temperature of 152 ° C. and a maximum operating temperature of 150 ° C.
Polyester resin F having an apparent melt viscosity of 2 × 10 ⁴ poise (Vylon GK150, manufactured by Toyobo Co., Ltd.), polyester resin G having an apparent melt viscosity of 8 × 10 ⁵ poise (Vylon 200: 24.2% by weight of terephthalic acid, 26.3% by weight of isophthalic acid, ethylene glycol
1%, 27.4% by weight of neopentyl glycol, manufactured by Toyobo Co., Ltd.) were each dissolved in methyl ethyl ketone and applied by a bar coater method, and the thickness after drying was 1 μm, 2 μm, and 8 μm. A resin layer was formed to obtain transfer films FB and FC for electrophotography. A matting agent and an antistatic agent were added in the same manner as in Example 1. Using the same color toner as in Example 1, a full-color fixed image was formed by the same method, and evaluation was performed by the same method as in Example 1. Table 2 shows the evaluation results.

[0049]

[Table 2]

From Table 2, it is clear that the apparent melt viscosity at the toner fixing temperature is clearly higher than that of the toner binder resin at the toner fixing temperature, and the molten toner inclination angle at the toner fixing temperature is larger than 40 degrees. The film FB is
The occurrence of pseudo contours was remarkably large, and the brightness and the saturation were also reduced, so that a preferable full-color projected image could not be obtained. A transfer film FB using a resin having an apparent melt viscosity lower than that of a toner binder resin at a toner fixing temperature, but having a melt toner inclination angle larger than 40 degrees in a transparent resin layer.
Is similar to FC, where false contours are remarkably generated, and brightness,
The saturation was also reduced, and a favorable full-color projected image could not be obtained.

[0051]

The transfer film for electrophotography of the present invention is
Since the transparent resin layer having the above configuration is provided on the intermediate adhesive layer, the fixing property of a full-color image is excellent, and the color image forming method by electrophotography has high lightness and saturation and high color tone. It is possible to easily form a full-color projection image having good reproducibility and free from false contours.

[Brief description of the drawings]

FIG. 1 shows a transparent resin layer and an intermediate adhesive layer
Transfer film for electrophotography of the present invention provided on one side of lum
FIG.

FIG. 2 shows a transparent resin layer and an intermediate adhesive layer formed of a plastic film.
Transfer film for electrophotography of the present invention provided on both sides of the film
FIG.

FIG. 3 is a view for forming a color image according to the present invention;
FIG. 1 is a schematic cross-sectional view of an electrophotographic apparatus.

FIG. 4 shows a toner toner used for measuring a molten toner inclination angle .
FIG. 3 is a cross-sectional view of a tablet frame for forming a mask.

FIG. 5 is a view showing a post-molding toner used for measuring a molten toner inclination angle.
FIG.

FIG. 6 illustrates a toner toner used for measuring a molten toner inclination angle .
FIG. 2 is a schematic cross-sectional view of an apparatus for melting and solidifying a disk.

[Explanation of symbols]

101: plastic film, 102: transparent resin layer,
103: intermediate adhesive layer, 104: antistatic layer, 1: electrostatic latent image holder, 2: black developing machine, 3: magenta developing machine,
4 cyan developer, 5 yellow developer, 8 charger,
9 Writing device, 10 Transfer drum, 11 Transfer device, 12 Cleaning device, 13 Transport device, 14
Fixing device, 14a: heat roll, 14b: pressure roll, 15, 16: supply tray, 17, 18: paper feed roller, 19, 20: paper feed guide, 21: charging device,
22: discharge tray, 23: contact roller.

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Koichi Makiyama 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd. In-house (72) Inventor Yoshio Shoko 2274 Hongo, Ebina-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. Hiroshi Sugizaki 2274 Hongo, Ebina-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. Ebina Works (56) References JP-A-52-37044 (JP, A) JP-A-3-198063 (JP, A) JP-A-4-125567 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) G03G 7/0 0

Claims (3)

(57) [Claims] An intermediate adhesive layer is provided on at least one surface of a plastic film having a heat-resistant temperature of 100 ° C. or higher, and is compatible with a binder resin of a toner to be fixed at a fixing temperature of the toner. in the fixing temperature of the toner, the melt apparent viscosity than the binder resin of the toner is rather low,
And a bisphenol derivative represented by the following formula (I):
All components, divalent or higher carboxylic acid or its acid-free
Hydrate or its lower alkyl ester as carboxylic acid component
A transfer film for electrophotography, comprising a transparent resin layer formed of a polyester resin contained as a resin . Embedded image Wherein R is an ethylene or propylene group, x and y are
Each is a positive integer of 1 or more, and the average value of x + y is
2-10. ) 2. An intermediate adhesive layer is provided on at least one surface of a plastic film having a heat resistance temperature of 100 ° C. or higher, and a molten toner inclination angle with a toner to be fixed at a fixing temperature of the toner is 40 degrees or less. bisphenol apparent melt viscosity at a temperature 100 ° C. is represented by Ah it is, and the following expressions 1 × 10 ³ ~7 × 10 ⁴ poise (I) induced
The conductor is a diol component and a divalent or higher carboxylic acid or
The acid anhydride or the lower alkyl ester is
Formed from a polyester resin contained as an acid component
2. The electrophotographic transfer film according to claim 1, wherein a transparent resin layer is provided. Embedded image Wherein R is an ethylene or propylene group, x and y are
Each is a positive integer of 1 or more, and the average value of x + y is
2-10. ) 3. A color toner image formed from a toner containing at least a colorant and a binder resin, is formed on the electrophotographic transfer film according to claim 1 or 2, and heat and A color image forming method comprising fixing by applying pressure.