JPH0124299B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrophotographic film. More specifically, using a polyester oriented film as a base material,
At least one surface of this base film is coated with a predetermined amount of matting agent and a resin layer serving as a specific binder, so that the surface resistivity value ranges from 1×10 ⁹ to 1×
An electrophotographic film with a toner receiving layer in the range of 10 ^{to 15} Ω, which has excellent transportability during copying, image density, and toner adhesion, as well as excellent solvent resistance and heat resistance. related to film for use.

Conventionally, plastic films such as polyester films, polysulfone films, cellulose ester films, and polycarbonate films have been used in electrophotographic transfer machines. To prevent misfeeding or double feeding of the film during copying, to prevent image disturbance due to charging, to prevent dust from adhering to the transfer paper, and to improve writing properties, the film is coated with a matting agent such as an inorganic compound. Many are coated. However, since conventional matting films contain large amounts of matting agents, they are opaque or have low transparency, and transparency is required for films for overhead projection using electrophotography and films for X-rays. It could not be used for the intended purpose.

Therefore, as a method to maintain transparency and improve conveyance (misfeed/double feed), image density, and interlayer adhesion between toner and base film, we developed a method using organic solvent-soluble binder resin and a relatively small amount of matting agent. A technique has been proposed in which a composition comprising the following, which has been subjected to antistatic treatment, is provided as a toner receiving layer on at least one surface of a base film.

Apart from this, recent advances in electronic copying machines have been remarkable, and extremely high-speed copying is now being put into practical use.
Due to the demand for high-speed copying, the toner fixing temperature during copying naturally tends to be set at a high temperature.

Incidentally, the electrophotographic film can also be used as an overhead projection film, an X-ray film, and the like. When used in this field, it has become necessary to have solvent resistance in addition to the above-mentioned properties as an electrophotographic film. For example, when a copied film is corrected, a solvent is used, so the film used needs to be resistant to solvents.
That is, it is desirable that the electrophotographic film has excellent transportability, image density, toner adhesion (adhesiveness), etc., as well as solvent resistance and heat resistance.

From this point of view, the conventionally proposed methods use a solvent-soluble resin as the binder resin, so the film with the toner-receiving layer does not have solvent resistance and cannot be used with erasing liquid, for example. When using this method to correct an image, it has the disadvantage that the image becomes very untidy.

The present invention provides an electrophotographic film that solves these problems. By using plastic film as a base material and providing a toner receiving layer on this base material, it has excellent solvent resistance and heat resistance, eliminates misfeeds and double feedings during copying, has high image density, and has excellent adhesion between the base film and toner. The present invention provides an electrophotographic film with excellent properties.

That is, the present invention uses a film of an organic polymer as a base material layer (base film), and has particles having a particle diameter of 0.01 μ (micron) to
The surface of the toner receiving layer is formed by forming a toner receiving layer containing 0.05% to 5% by weight of a matting agent of 10μ and a binder resin whose main components are a polyester resin and/or an acrylic resin insoluble in an organic solvent. Specific resistance value is 1×10 ⁹ Ω to 1×10 ¹⁵ Ω
This is an electrophotographic film in the range of .

The electrophotographic film according to the present invention contains a resin and a matting agent on both surfaces of the base film, and has a surface resistivity value of 1×10 ⁹ to 1×10 ^{15 .}
A toner receiving layer having a toner in the range of Ω is convenient because it has excellent conveyance properties and there is no need to distinguish between a copying surface and a non-copying surface during use. However, it is also possible to have a toner receiving layer on one surface of the base film. However, in this case, it is preferable to provide an antistatic layer on the opposite side of the toner receiving layer.

Examples of base films made of organic polymers that can be used in the present invention include polyester films such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate films, cellulose acetate films, polysulfone films, polyphenylene oxide films, polyimide films, and polyamide films. Polymer films with excellent heat resistance and transparency such as , etc. are suitable. In particular, thermoplastic aromatic polyesters such as polyethylene terephthalate and polyethylene naphthalate can be preferably used. In the case of polyester film, it has a high degree of dimensional stability as a base material, for example, the heat shrinkage rate (JISC-2318) is preferably 1.5% or less in both the vertical and horizontal directions, and 1.0%.
The following are particularly preferred.

As mentioned above, heat fixing during copying is carried out at a relatively high temperature in the range of 180 to 200°C, so if a film with poor heat resistance is copied with a dry electrophotographic copying machine, the surface flatness of the film will be lost. It has little practicality.

The base film applicable to the present invention may contain additives such as colorants and lubricants as long as the performance as an electrophotographic film is not impaired. It is well known that the film used as an X-ray film is colored blue, and this type of film can also be applied to the base material of the present invention.

The matting agents used in the present invention include inorganic fine particles such as silicon dioxide, calcium carbonate, talc, and clay, polymer powders such as polyethylene, polypropylene, polyacrylonitrile, polystyrene, polyvinyl chloride, polycarbonate, and polyethylene terephthalate; A spurge body is used. In particular, spherical plastic powder or dispersion bodies are preferably used. A matting agent having an average fine particle size (primary particle size) of 0.01 μm to 10 μm can be used, and the particle size of the matting agent can be appropriately selected depending on the thickness of the toner receiving layer. However, the particle size of the matte agent
If it is less than 0.01μ, the slipperiness of the film will be poor and problems such as misfeed from the paper feed tray and double feeding during copying will likely occur. If the thickness exceeds 10μ, the film will have a rough surface, and as with the case where the thickness is less than 0.01μ, the slipperiness of the film will decrease and tumble will occur more easily, and the clarity of the copied image will be impaired.
The amount of matting agent added is based on the binder resin.
0.01% to 5% by weight are suitable, particularly preferably 0.1% to 2% by weight. If the amount of the matting agent added is less than 0.01% by weight, the slipperiness between the films will be low and misfeed or double feeding troubles will easily occur during copying. Moreover, if it exceeds 5% by weight, transparency will be impaired and it will not be suitable for overhead projection films, X-ray films, etc.

Examples of binder resin components insoluble in organic solvents that can be applied to the present invention include polyester resins, polyether ester resins; and acrylic monomers such as acrylic ester copolymers, methacrylic ester copolymers, and acrylic styrene copolymers. At least one type of acrylic resin containing 30 mol% or more of the component is mentioned. These binder resins can be used as water-soluble, emulsifiable or water-dispersible. In addition, as a resin insolubilized in an organic solvent,
30 mol of acrylic monomer such as polyester resin, polyether ester resin, acrylic ester resin, methacrylic ester resin, copolymer of styrene and acrylic ester, copolymer of styrene and methacrylic ester, acrylic polyol, etc. % or more of at least one type of acrylic resin, and includes those obtained by self-crosslinking or crosslinking between different polymers. Furthermore, polyester resin and/or acrylic resin, isocyanate compound, amino resin,
Insolubilized resins can also be obtained by reacting with epoxy resins, phenolic resins, etc. Examples of such isocyanate compounds include tolylene diisocyanate, P,P'-diphenylmethane diisocyanate, xylene diisocyanate, hexamethylene diisocyanate, and the like.

As the epoxy resin, glycidyl ethers of polyhydroxy compounds, glycidyl esters of polycarboxylic acids, etc. can be used. Amino resins include melamine, guanamine, benzoguanamine,
A methylolated amino compound obtained by reacting an amino compound such as urea with formaldehyde, a methylolated amino compound obtained by methylating or butylating this methylolated amino compound with an alcohol such as methanol or butanol, or an initial condensate thereof. etc. can be applied.

As the phenolic resin, a well-known resol type phenolic resin or the like can be used. Among such insolubilized polyester resins and/or acrylic resins, isocyanate compounds,
Melamine resin and epoxy resin are preferred. The polyester, acrylic resin, isocyanate compound, epoxy resin, amino resin, etc. that provides the resin insolubilized in the organic solvent may be provided in a form soluble in the organic solvent, and may be in the form of an aqueous solution, an aqueous emulsion, or a dispersion. It may be provided in

The surface resistivity value of the toner receiving layer is suitably in the range of 1×10 ⁹ Ω to 1×10 ¹⁵ Ω. If the surface resistivity value is less than 1×10 ⁹ , toner image transfer during copying will not be performed sufficiently, resulting in low image density on the transfer film. On the other hand, if the resistance exceeds 1 x 10 ¹⁵ Ω, the film will become electrostatically charged and dust will easily adhere to it during handling, and problems such as misfeeds and double feedings will often occur during copying. Moreover, the surface specific resistance value is 1
If the resistance exceeds ×10 ¹⁵ Ω, the charges accumulated during copying will not be removed for a long time, causing mutual blocking between the films and causing problems in handling.

The surface resistivity value of the toner receiving layer can be adjusted to a range of 1×10 ⁹ to 1×10 ¹⁵ Ω by any known method, but an effective method is to include an antistatic agent in the binder resin of the receiving layer. It is something that makes you As the antistatic agent, known ones such as alkyl phosphate salts, alkyl sulfate salts, and quaternary ammonium salts may be used.

The toner receiving layer is made of a composition containing the above-mentioned matting agent, binder resin, and, if necessary, an antistatic agent. Furthermore, thermoplastic synthetic resins, natural resins, colorants, ultraviolet absorbers, stabilizers, lubricants, antiblocking agents, curing accelerators, and the like may be added to the extent that they do not impair the performance of the electrophotographic film.

The electrophotographic film of the present invention can be obtained by coating at least one surface of the base film with a toner receiving layer.

The toner-receiving layer can be applied by a known method using a coating mechanism that is known per se, such as an air doctor coater, a blend coater, a rod coater, a knife coater, a squeezed coater, a reverse roll coater, and the like.

The electrophotographic film of the present invention has excellent transparency, solvent resistance, and heat resistance, and even if it is continuously copied using an electronic copying machine, it will not cause misfeeds or double feeding from the paper feed tray. There is an advantage that it does not happen. Furthermore, there are no image disturbances or transfer defects caused by electrostatic interference, and the images obtained are clear and high in density.
A transfer film with excellent adhesion to the toner receiving layer can be obtained.

This electrophotographic film is useful in a variety of applications including overhead projection applications and x-ray applications.

The present invention will be explained below with reference to Examples. The surface resistivity values in Examples were measured 1 minute after energization using an insulation meter manufactured by Takeda Riken Co., Ltd. The sample for measurement was conditioned for 24 hours at a temperature of 23°C and a relative humidity of 65%. The softening point was measured by the ring and ball method (JIS-K2531). Molecular weight is VPO
It was measured by the method.

Example 1 A 10 weight product containing a water-soluble copolyester containing sodium sulfonate base (molecular weight 5000, softening point 140°C), water-soluble methylolmelamine, and a crosslinking catalyst in a solid ratio of 67:30:3 % aqueous solution
100 parts, 0.1 part of calcium carbonate having an average particle size of 1 μm, and 0.15 parts of dioctyl phosphate triethanolamine salt (antistatic agent) were added and uniformly dispersed. This aqueous solution was applied to both surfaces of a 100μ thick biaxially oriented polyethylene terephthalate film using a percoater until the thickness was 1μ when wet.
It was coated so that it became transparent and heat treated with hot air at 130℃ for 3 minutes, resulting in good transparency and a surface resistivity value of 1.
An electrophotographic film of ×10 ¹¹ Ω was obtained. Even when the electrophotographic film thus obtained was lightly rubbed with toluene-containing gauze, no change was observed, and the film had excellent solvent resistance.

50 copies of electrophotographic film using a high-speed copying machine
When copies were made in succession, there were no misfeeds or double feeding troubles, and the resulting copy film had no disturbances in the toner-receiving layer coated surface or images, and had high image density. The toner that adhered to the toner during copying was completely adhered to the toner receiving layer when an adhesive strength test was performed in which cellophane tape was applied to the toner surface and then peeled off, and only a small amount of toner was observed to fall off. It was hot.

Comparative example 1 Methyl ethyl ketone/ethyl acetate/toluene =
To 100 parts of a 10% by weight solution of copolymerized polyester [molecular weight 15000, softening point 165°C] dissolved in a 1/1/1 mixed solvent, 0.1 part of calcium carbonate with an average particle size of 1 μ and potassium dioctyl phosphate (antistatic agent) were added. )0.15
parts were added and uniformly dispersed.

Using this solution, a film having a surface resistivity of 2×10 ¹¹ was obtained in the same manner as in Example 1. When this film was lightly rubbed with gauze containing toluene, the coating layer (toner receiving layer) was easily separated, and it was found that the film had poor solvent resistance.

Example 2 A water-soluble copolymerized polyester containing a sulfonic acid Na base (molecular weight 5000, softening point 140°C), an aqueous acrylic-styrene copolymer, a water-soluble methylolmelamine, and a crosslinking catalyst were mixed in a solid content ratio of 55: 15:
0.05 part of silicon dioxide having an average particle size of 1.5 μm and 0.10 part of potassium dioctyl phosphate were added to 100 parts of a 10% by weight aqueous solution containing the mixture in a ratio of 30:3 to disperse the silica well. An electrophotographic film with good transparency and a surface resistivity of 2×10 ¹² Ω was obtained in the same manner as in Example 1 using an aqueous solution.

Even when this electrophotographic film was lightly rubbed with toluene-containing gauze, no change was observed, and the film had excellent solvent resistance. When a copying test was conducted in the same manner as in Example 1, Example 1 was obtained.
Similarly, good copying results were obtained.

Example 3 A 10% by weight solution (methyl ethyl ketone/ethyl acetate/toluene =
0.05 part of polyolefin powder having an average particle size of 3 μm and 0.5 part of dioctyl potassium phosphate were added to 100 parts of a 1/1/1 mixed solvent, and the polyolefin powder was uniformly dispersed. Using this solution, an electrophotographic film with good transparency and a surface resistivity of 5×10 ¹¹ Ω was obtained in the same manner as in Example 1. Even when this electrophotographic film was rubbed with gauze containing toluene, no change was observed, indicating that the film had excellent solvent resistance. In addition, satisfactory results were obtained in a copying test conducted in the same manner as in Example 1.

Example 4 Water-soluble copolyester containing sulfonic acid Na base (molecular weight 10000, softening point 170°C) 5
% aqueous solution, 0.015 part of polyacrylonitrile powder with an average particle size of 5 μm and 0.04 part of dioctyl phosphate monoethanolamine salt were added, and the polyacrylonitrile powder was uniformly dispersed in the aqueous solution. The solution was applied by the same method as in Example 1, and the surface resistivity with good transparency was 1×.
An electrophotographic film of 10 ¹³ Ω was obtained. This electrophotographic film showed no change even when rubbed with gauze containing toluene, and was a film with excellent solvent resistance. A copying test was carried out in the same manner as in Example 1, and satisfactory results were obtained.

Claims (1)

[Claims] 1 A binder resin containing matting agent particles is applied to the base layer of the polymer film and one or both surfaces of the base layer to increase the surface resistivity to 1×.
In an electrophotographic film comprising a toner receiving layer with a resistance of 10 ⁹ Ω to 1×10 ¹⁵ Ω, the binder resin is a polyester resin and/or acrylic resin that is insoluble in an organic solvent or that has been treated to be insolubilized in an organic solvent. The main component is resin, and the matting agent particles have a particle size of 0.01μ (micron) to 10μ.
1. An electrophotographic film comprising a toner receiving layer in which 0.05% to 5% by weight (based on binder resin) is dispersed.