DE2301466A1 - ELECTROPHOTOGRAPHIC COPY FILM - Google Patents

Description

PATENT LAWYERS

DR-E. WIEGAND DIPL-ING. W. NIEAAANN DR. M. KÖHLER DIPL-ING. C GERNHARDT

MÖNCHEN HAMBURG

TELEPHONE: 555 476 8000 MÖNCHEN 15, 12.JgKlUaI * 1973

TELEGRAMS: KARPATENT NUSSBAUMSTRASSE

41 440/73 - Ko / Yes

Photo Film Co. Ltd. Minami Ashigara-shi, Kanagawa (Japan)

Electrophotographic copy film

The invention relates to an electrophotographic coating film and more particularly to an electrophotographic coating film to a temperature of 10O ⁰ C or more resistant plastic film comprises on a a coating layer comprising a styrene-acrylate or methacrylate esters copolymer having a styrene content of at least 10 wt.% contains.

According to the invention there is an electrophotographic

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Coating film with improved receptivity for electrophotographic see toner and a reduced tendency to block indicated, which has a thermally stable film base and a coating layer which contains 0.1 to 10 % by weight of one or more matting agents and is formed from resins which are a styrene Acrylate or methacrylate ester copolymer containing at least 10 percent by weight of copolymerized styrene.

It has been widely used as electrophotographic coating films for dry processes such as the Xerox system, uncoated polyester films and with an organic solvent-soluble ester resin coated polyester films are used. These usual electrophotographic Coating films, however, have some disadvantages in that they have a coating image thereon of low optical density due to the poor thermal fixation or compatibility with an electrophotographic see toner, and when a stack of numerous sheets of such a film in a copier for making a Number of copies is made, sometimes two or more sheets of paper are pulled out of the feed tray at the same time.

The object of the invention consists in an improved electrophotographi see coating film that has high thermal fixation or compatibility for electrophotographic Toner, gives a coated image of high optical density, and from the feed tray without double feed can be deducted.

It has been found that the above object is achieved by using a styrene-acrylic or methacrylic ester copolymer of resins which have a styrene content of at least 10% by weight _? is applied to a plastic film together with a matting agent which is opposite to temperatures of 100 ⁰ C or more stable (as determined by ASTM method no. D 759-66 by measuring the resistance

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of the plastic film against heat (softening point). In this context is referred to "Modern Plastics Encyclopedia" 1971-1972, pages 622 to 625, McGraw-Hill, Inc.)

It is difficult to satisfactorily achieve the above object using an ester resin, acrylic ester resin or methacrylic ester resin alone.

The above-mentioned matting agent-containing resin layer may be on a single surface or on the two surfaces of the plastic film are applied. When having a single surface of a plastic film one matte resin layer, it is preferred to have an antistatic coating layer on the other Apply surface.

In the drawings, FIGS. 1 and 2 show cross sections of electrophotographic films according to the invention.

In Figs. 1 and 2 1 denotes a Art st of film with a thermal resistance of 10O ⁰ C or more, 2 denotes a coating resin layer comprising a styrene-acrylate or -Hethacrylatester copolymer having a styrene content of at least 10 wt.% in which a matting agent has been incorporated according to the invention, and 3 denotes an antistatic coating layer.

The acrylic and methacrylic acid esters in the copolymers of styrene with an acrylic acid ester or a methacrylic acid ester to be used for carrying out the invention are illustrated, for example, by the following: methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, n-butyl methacrylate and isobutyl methacrylate. The alkyl acrylates or alkyl methacrylates having 1 to 5 carbon atoms in the alkyl group are preferred. In the copolymer, styrene is preferably used in an amount of at least 10 wt.% Up to 90 wt.%, More preferably 20 to 80 wt.%, More favorable in an amount of 20 Gev.% Or more is used and accordingly, an acrylic or Methacrylic acid ester in one

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An amount of at most 90% by weight , more favorably used in an amount of 80% by weight or less. These copolymers are generally used with a molecular weight of from about 10,000 to about 200,000, more preferably from 50,000 to 150,000. Although somewhat higher and lower molecular weights can be used, the results are generally not as good as when carried out within the broad range given. Resins which can be used for carrying out the invention and which can be present together with the copolymer include, for example, the following: nitrocellulose, cellulose acetate and other cellulose esters, an ester resin which is soluble in organic solvents, for example polymeric mixed terephthalic acid esters according to US Pat. No. 3,100,722, polycarbonate, Polysulfones, polyvinylidene chloride and polyphenylene oxide with a molecular weight of 100,000 to 250,000. These additional resins serve to increase the thermal stability of the copolymers used according to the invention. The expression "polymeric mixed terephthalic acid esters" denotes copolyesters which are obtained by esterification and polycondensation of mixtures of terephthalic acid and at least one other dicarboxylic acids, for example isophthalic acid, orthophthalic acid, adipic acid or sebacic acid, with dihydric alcohols containing up to 10 carbon atoms in the molecule will. Alcohols of this type are, for example, ethylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, heptamethylene glycol, decamethylene glycol and propylene glycol. The polymeric mixed terephthalic acid esters to be used according to the invention are known. Excellent results are obtained using mixed esters obtained from mixtures of acids having 10 to 50 moles of the other dicarboxylic acid per 100 moles of terephthalic acid. The copolymer is preferably used in an amount of 5 to 100% by weight of the total weight of the in

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the coating layer present resin used, that the additional resin optionally. in an amount of O to 95% by weight is used.

In general, a solvent for coating ease is added to the solution of the coating resins comprising the copolymer contain, used, for example, methanol, ethanol and similar alcohols; Acetone, methyl ethyl ketone and the like Ketones; Methylene chloride, ethylene chloride, tetrachloroethane and similar chlorinated hydrocarbons and their Mixtures. The solvent is removed during the final film formation.

When using such a solution on a polyester film as a film base, the solution can contain a Swelling agents for the polyester film can be incorporated to improve the adhesion between the copolymer layer and the polyester film to increase. The swelling agent for the polyester film is expediently in an amount of 2 to 10 wt. based on the total weight of the solvent applied. The swelling agents expediently used for the polyester film include, for example, phenol, resorcinol, o-chlorophenol, p-chlorophenol, cresol and similar phenol derivatives, Benzoic acid, salicylic acid, salicylic acid ester, monochloroacetic acid, trichloroacetic acid, trifluoroacetic acid, 2-nitropropanol, Benzyl alcohol, benzaldehyde, acetonylacetone, acetophenone, benzamide, benzonitrile and methyl nicotinate.

Different methods used to make the styrene-acrylate and styrene-methacrylate copolymers can, are in E.H. Ryddle "Monomeric Acrylic Esters", page 93, 1954, Reinhold Publishing Co.

Separately, a matting solution is prepared by dissolving a copolymer according to the invention and optionally dissolving other additional resins in a solvent to form a solution with 10 to 50 % by weight of the copolymer and other resin, adding a matting to the solution obtained.

309829 / 107B

agent with an average particle size of 0.1 to 10 / um, preferably 1 to 5 / umj in preparation of a solution, the 10 to 50 wt. 96 of a total amount of the copolymer and of the optionally used resin and 0.5 to 15 wt. # of the matting agent is added, for example fine Particles of silicon dioxide, starch or aluminum oxide or a plastic powder, e.g. polyethylene, polyester or polyacrylonitrile and the mixture obtained is stirred with an effective stirrer in order to add the matting agent to disperse the solution evenly. The matting agents preferably have a size of 0.1 to 10 μm, more preferably from 1 to 5 µm.

The final coating solution is then prepared by adding the matting solution to the solution of a copolyraeren according to is added to the invention, if necessary, a colorant and / or other optical additives are added, the resulting system is thoroughly stirred and then the mixture is stirred to remove any impurities or undissolved substances which may be present in the mixture, is filtered so that the total surface properties are equally good and avoid any tendency towards unevenness of the coating. As a coloring agent organic pigments such as anthraquinone dyes and derivatives such as 1- (p-methylphenylamino ) -4-hydroxyanthraquinone, 1,4-diphenylaminoanthraquinone, i-anilino-4-hydroxyanthraquinone, 1,4-di (m-methylphenylamino) anthraquinone and similar dyes; Azo dyes and their derivatives; Triphenylmethane dyes and their derivatives; Quinoline dyes and their derivatives; inorganic pigments such as carbon black, titanium white, White lead, red iron oxide and the like can be used.

The matting agent is preferably added in an amount of 0.1 to 10 wt.% Of the copolymer. An amount less than 0.1 wt. # Is not enough to prevent double feeding from one feed tray and

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230U66

Use of a matting agent in a 10 wt.% Amount exceeding leads to a poorer quality copied image.

The coating solution obtained in this way is applied to a plastic film with a thermal resistance that can ^{withstand temperatures of 100 °} C. or more, such as, for example, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyamide, polycarbonate, cellulose ester or polyamide in such an amount that a dried coating film with a thickness of 0.3 to 5 µm is obtained.

If only one side of the thermally resistant plastic film is coated with the copolymer / matting agent, the opposite side is preferably with coated with an antistatic coating layer, generally dried has a thickness of less than 1.0 / µm, preferably 0.1 to 0.5 / µm. Then contains the antistatic Coating solution usually 0.01 to 2.0 wt. # Of antistatic agent. The solvent for the antistatic Coating solution is usually the same solvent as that used for dissolving the copolymer according to the invention and the other Additional resin is used. Furthermore, 0.5 to 5 »O by weight 96 of the additional resin can be used as a binder in the antistatic The coating solution containing 0.01 to 2.0% by weight of an antistatic agent can be dissolved. In this case, the coating layer possesses usually a thickness of 0.5 to 3.0 µm when dry. An anti-static coating solution that contains a binder gives the same effect as an antistatic coating solution without a binder, but is antistatic effect more permanent, i.e. the antistatic layer contains 2.0 to 40% by weight of the antistatic agent, based on the total weight of the binder resins.

The antistatic agents that can be used according to the invention are naphthalene sulfonates, ethylene oxide addition products, Phosphoric acid esters, anionic surface-active agents, such as alkyl metal sulfates, alkylaryl metal sulfates,

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Alkylnaphthalene metal sulfates and alkyl metal sulfonates, the each have 10 to 20 carbon atoms in the alkyl portion and wherein the metal is Na, K, Mg or Ca, cationic surfactants such as alkylamine salts with 10 to 20 carbon atoms in the alkyl portion with a metal such as Na, K, Mg or Ca, alkyldimethylammonium chlorides with 10 to 20 carbon atoms in the alkyl portion and dialkyldimethylammonium chlorides with 10 to 20 carbon atoms in the alkyl moiety and nonionic "surfactants" such as polyoxyethylene alkylphenols with 10 to 20 carbon atoms in the alkyl portion and polyoxyethylene polyalcohols, the alcohol from aliphatic Alcohols with 10 to 20 carbon atoms.

Plastic films with thermal resistance that ^{cannot withstand temperatures of 100 °} C. or more are unsuitable for the present invention because they curl or otherwise deform when used in a Xerox machine or a similar electronic dry copier. The thickness of the plastic film is preferably on the order of 50 to 200 µm. The electrophotographic film thus obtained fuses well with an electrophotographic toner and gives a copied image of high optical density when subjected to a copying process in an electronic dry copier and can be sequentially peeled from a feed tray without double feeding. The electrophotographic printing film thus obtained is of great use for, for example, overhead projection and two-sided copying.

The invention will now be explained in detail with the aid of the following examples, in which all parts and percentages are based on weight.

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example 1

4 parts of a copolymer of 65% styrene with 35 % butyl acrylate (average molecular weight 150,000) were dissolved in 100 parts of a mixture of ethylene chloride, methylene chloride, phenol, tetrachloroethane in a ratio of 16: 2: 1: 1. 44 parts of the same copolymer were dissolved in 150 parts of the above solvent, and 6 parts of finely divided polyacrylonitrile was added thereto as a matting agent with stirring. 2.0 parts of this matting solution was then dissolved in the above coating solution with stirring. The solution was then applied to both sides of a polyester film having a thickness of 100 µm in an amount such that a dry coating film having a thickness of 1.3 µm was obtained on each side, thereby giving a coating film. The electrophotographic film thus obtained was superior to an ester resin-coated polyester film (Conventional Product 1) and an uncoated polyester film (Conventional Product 2) in Table I above.

Table I.

Used electronic usual
duct 1 Copier: Xerox 720, Product after
example 1 Fuji-Xerox Co. B. A. B. Pro-usual
Product 2 A. Image density no B. no thermal fixation
of the toner D. Double feed just one there both upper Usefulness Upper only one

surface usable surface areas bar usable usable

Double Feed: This term means that when a stack of sheets of printing film is fed into the feed tray of an electronic

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See the copier is loaded, two or more sheets of film are peeled off at the same time, or removed from the feed tray.
Evaluation: A excellent, B good, C moderate, D bad.

The image density was evaluated by sight; the thermal fixation of the toner was determined by comparing the releasing property the thermally fixed surface is determined by scratching the surface with a fingernail.

Example 2

On a single surface of a polyphenylene oxide film having a thickness of 100 µm, the same solution as in Example 1 was applied to form a coating film with a dry thickness of 1.5 µm and on the other Surface became a solution of one part of an antistatic agent, alkylbenzimidazole sulfonate in 500 parts of a Mixture of methanol and acetone in a ratio of 1: 1 under Formation of a coating layer applied with a dry thickness of 0.8 / µm. The coating film thus obtained was one Superior to uncoated polyphenylene oxide film in the points indicated in Table II.

Table II

Electronic copier used: Xerox 720, Fuji-Xerox Co.

not exaggerated
Movie there overdone
Movie Image density B. both sides
useful A. thermal fixation
of the toner D The evaluation standards were in this A. Double feed as in example 1. no Usefulness only one waiter
usable area Example the same

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Example 5

A solution of 4 parts of a copolymer of 20 % styrene and 80 % methylinethacrylate (average molecular weight 120,000), which was prepared as in Example 1, was applied to a polycarbonate film with a thickness of 100 μm to form a coating layer with a dry thickness of 2 .0 / µm on each side of the polycarbonate film (coated with coating film on both sides). On the other hand, the coating solution was applied to a single surface of another polycarbonate film having a thickness of 100 µm as in Example 2, and then, on the other surface, a solution of one part of an antistatic agent, alkylbenzimidazole sulfonate, in 500 parts of a mixture of methanol and Acetone in a ratio of 1: 1 to form an antistatic coating with a dry thickness of 0.5 µm (one side covered with coating film).

The two thus obtained according to the invention Films were superior to uncoated polycarbonate film on the points listed in "Table III.

Table III

Electronic copier used: Xerox 720, Fuji-Xerox Co.

not covered
a movie both be
ten over
pulled one a
umpteenth page
Overzopen Image density B. A ^f A. thermal fixation
of the toner C. A. A. Double feed Yes no there Usefulness both sides
useful both be
th need
bar just one
Page need
bar

3 0 9 8 2 9/1 0 7 B.

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The evaluation standards were the same as in Example 1 except that A was divided into two grades, A and A ¹ , and evaluation was made into five grades, A, A ¹ , B, C and D.

Example 4

A solution of 4 parts of a copolymer of 80 % styrene and 20 % isobutyl methacrylate (average molecular weight 90,000), which had been prepared according to Example 1, was applied to both sides of a polysulfone film of 80 μm thickness to form coating layers with a thickness of 2 .5 / µm in the dry state (both sides coated film). Separately, only one surface of another polysulfone film was coated as in Example 2 on a single surface as in Example 2 and on the other surface of the film was a solution of one part of an antistatic agent, alkylbenzimidazole sulfonate, in 500 parts of a mixture of methanol and acetone in a ratio of 1; 1 with the formation of a dry antistatic coating layer with a thickness of 1.0 / µm (one single side with coated film) applied woivicai.

Compared to an uncoated Polysulioiililm the Fi 1 thus obtained were me in the Table. IV consider the points given.

Table IV

Used electronic copyifjej Hi: Xerox 720, Fuji-Xerox Co.

nichtüberzoge "both sides a einzi- ner I'iliu 1 <ίι exceeded ne page

n overdrawn

Bilddiehie HA «/, ^f

thermiijoliu 1 a yi (nuif

of the toner Ii /. A.

Double feed, 1a *. in-in no

Usefulness both sides brmi <h- l-cide iJpi- just dna

ί ηι It ¹ Ii custom- iU-Hf *

The evaluation standards were the same as in Example 3.

Example 5

In 100 parts of a mixture of methylene chloride and tetrachloroethane in a ratio of 9: 1, 1.5 parts of a copolymer of 65 % styrene with 35 % buty (average molecular weight 80,000) and 3.5 parts of an ester resin (ester resin 20 from Toyobo Co. Ltd.) solved. In 120 parts of the above solution, 35 parts of a mixture of the above copolymer (30% by weight and ester resin (50% by weight) was dissolved, and then 0.06 part of finely divided silica as a matting agent was added thereto with stirring Matting solution was dissolved in the above coating solution with stirring.

The solution then became on both sides of a polyethylene terephthalate film with a thickness of 80 / µm to form a coating layer with a dry thickness of 2.0 / µm upset. The copier film thus obtained compared with uncoated polyethylene terephthalate film in the ranges shown in Table V. consider specified points.

Table V

Electronic copier used: Xerox 720, Fuji-Xerox Co. Ltd.

uncoated - on both sides

a movie 309829/1076 coated film Image density B A. thermal fixation of the toner D A. Double feed yes no Usability both sides both sides need useful bar. The evaluation standards were the same as in both game 1. ., .. "cr. _Nq atf; a cue «..-- * i- ^: ~" /

Example 6

£ A solution of 5.0 parts of nitrocellulose (RS 1/16, Da \ cel Ltd .; 1/16 sec, measured according to the JS K-6703 "ring drip method" on a solution of 12.2 % by weight Nitrocellulose, 22.0% by weight of ethanol, 17.5% by weight of ethyl acetate and 48.3% by weight of toluene, using this method to measure the dropping speed of a polymer solution into a glass tube with a diameter of 25 mm and a length of 254 mm and the pipe has an iron ring with a diameter of 7 to 9 mm and a weight of 7 g) and 0.5 part of a copolymer of 20 % styrene and 80 % methyl methacrylate (average molecular weight 50,000) and 3.0 parts of a like Matting solutions described in Example 5 were prepared in a similar manner to Example 5 and applied to a polycarbonate film having a thickness of 120 µm to form a coating layer having a dry thickness of 2.5 µm on each side of the polycarbonate film (a copier film coated on both sides ) applied. The copier film thus obtained was superior to an uncoated polycarbonate film in the points shown in Table VI.

Table VI

Electronic copier used: Xerox 720, Fuji-Xerox Co. Ltd.

uncoated film coated on both sides

Image density Bc A

thermal fixation

of the toner D A

Double feed yes no

Usability both sides both sides

usable usable

The evaluation standards were the same as in Example 1.. r

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The invention has been described above on the basis of preferred embodiments without being limited to it.

3 0 9 8 2 M / 1 0 7

Claims (1)

Claims Ci "'electrophotographic Kopierf ilm geke η η is characterized by a thermally resistant plastic film which is resistant to temperatures of 10O ⁰ C or more, with a formed of resin fitted to the surface coating layer, wherein the resin is a copolymer of at least 10 wt.% Styrene with a correspondingly at most 90 % by weight of a comonomer of acrylic and / or methacrylic acid esters and the coating layer contains 0.1 to 10 % by weight, based on the weight of the copolymer, of one or more matting agents. 2. Electrophotographic copier film according to claim 1, characterized in that the molecular weight of the copolymer is about 10,000 to 200,000. 3, Electrophotographic copying film according to claim 1 or 2, characterized by that the acrylic and methacrylic esters, alkyl acrylates or alkyl methacrylates with 1 to 5 carbon atoms in the alkyl group are. k. Electrophotographic copier film according to claims 1 to 3 3, characterized in that the Resin coating layer the copolymer and at least one additional Contains additional resin different from the copolymer. V 'VAV 9/1 Π 7 K 5. Electrophotographic copy film according to claim 4, characterized in that at least one additional resin is a cellulose ester / organic solvents soluble ester resins, a polycarbonate, a polysulfone, a polyvinylidene chloride or a polyphenylene oxide. 6. Electrophotographic copier film according to claim 1 to 5, characterized in that the amount of the additive resin is at least 5% by weight of the total weight of the resins present in the coating layer. 7. Electrophotographic coating film according to claim 1 to 6, characterized in that the matting agent has an average particle size of 0.1 to 10 / µm. 8. Electrophotographic copier film according to claim 1 to 7, characterized in that the matting agent made of silicon dioxide, starch, aluminum oxide, and / or a plastic powder. 9. Electrophotographic copy film according to claim 1 to 8, characterized in that the plastic film made of polyalkylene terephthalate, a polysulfone, a polyphenylene oxide, a polyimide, a polycarbonate, a cellulose ester and / or a polyamide. 10. Electrophotographic copier film characterized by a thermally resistant plastic film carrier that is exposed to temperatures of 10CPC or is more resistant, the coating layer formed from resins on opposite surfaces (1), wherein the Resin is a copolymer of at least 10% by weight of styrene with corresponding at most 90% by weight of a comonomer made of acrylic 309829/1 075 " ¹⁸ " 230H66 acid and / or methacrylic acid esters is formed and the coating layer contains 0.1 to 10% by weight, based on the weight of the copolymer] !, one or more matting agents and (2) contains a coated antistatic layer. 11. Electrophotographic copy film according to claim 10, characterized in that the molecular weight of the copolymer is about 10,000 to 200,000. 12. Electrophotographic copy film according to claim 10 or 11, characterized in that the acrylic acid and methacrylic acid esters or alkyl acrylates Are alkyl methacrylates having 1 to 5 carbon atoms in the alkyl group. 13. Electrophotographic copying film according to claim 10 bis 12, characterized in that the resin coating layer is the copolymer and at least one Contains additional resin other than the copolymer. 14. Electrophotographic copier film according to claim 13 »characterized geke η nzeich that at least one additional resin, a cellulose ester, ester resins soluble in organic solvents, a polycarbonate Polysulfone, a polyvinylidene chloride or a polyphenylene oxide is. 15. An electrophotographic copying film according to claim 13, characterized in that the amount of the additive resin is at least 5% by weight of the total weight of the resins present in the coating layer. 309829/1 075 230H66 16. Electrophotographic copying film according to claim 10 bis 15, characterized in that the matting agent has an average particle size of 0.1 "to 10 µm. 17. Electrophotographic copying film according to claim 10 bis 16, characterized in that the matting agent consists of silicon dioxide, starch, aluminum oxide and / or a plastic powder. 18. Electrophotographic copying film according to claim 10 to 17, characterized in that the plastic film made of polyethylene terephthalate, a poly-sulfone, a polyphenylene oxide, a polyimide, a polycarbonate, a cellulose ester or a polyamide. 19. Electrophotographic copying film according to claim 10 bis 18, characterized in that the antistatic layer is an antistatic agent with a Contains dry starch from 0.1 to 0.5 / µm. 20. Electrophotographic copy film according to claim 19, characterized in that the antistatic Means from liaplithalinsulfonaten, ethylene oxide addition products and / or phosphoric acid esters. 21 «electrophotographic copier according to claim 10 to 20, characterized in that the anti-static layer contains a binding resin. 22. 153 <> 3itrophotossraphic copii-ri'i3m according to claim 21, characterized by ο k ο η η ζ e ΐ ·. h η <·. i see that din anti rtii-l i? 2.0 layer 4 <y>Oew.'i IMT ii.iati see Hitte3 _f his relative aui the Gesamtgewic] i1 ui-.r ^ Jiindorhiirze with finer 11 9 «/ M / 1 U 7 Iy Has dry thickness of 0.5 to 3.0 / µm. 23. Electrophotographic copy film according to claim 22, characterized in that the Binder resin made from cellulose esters, ester resins soluble in organic solvents, polycarbonates, polysulfones, polyvinylidene chloride and / or polyphenylene oxides. 309829/107 5