CH633640A5 - Process for producing a photosensitive photographic film - Google Patents

Description

The present invention thus relates to the method defined in claim 1.

The light-sensitive silver halide emulsions used according to the invention adhere directly to the copolymeric primer layer of the film base treated with a coro-ion discharge, without further treatment or coating, e.g. with a gelatinous intermediate layer.

This is simpler and more economical with regard to the production, and certain technical disadvantages which can be associated with gelatinous layers are avoided. Such disadvantages are e.g. their stickiness in damp or wet conditions, their high surface friction, which can lead to winding problems, the optical interference patterns on the film, the build-up of static charge 20 and an effect called "aging on contact" and of components such as such as curing agents that are contained in coatings that are on the other side of the film and that, when the coated film is wound on a roll, migrate into the gelatinous intermediate layer and cause premature crosslinking of the gelatinous intermediate layer, which the adhesion of the photosensitive emulsion to the gelatin intermediate layer is impaired.

The self-supporting plastic film can be any suitable plastic film, e.g. from polysulfones and linear poly-30 esters, which are obtained by condensing one or more dicarboxylic acids or their diesters with lower alkyl groups, for example terephthalic acid, isophthalic acid, phthalic acid, 2,5-, 2,6- and 2,7-naphthalenedicarboxylic acid, Succinic acid, sebacic acid, adipic acid, azelaic acid, diphenyldicarboxylic acid 35 and hexahydroterephthalic acid or bis-p-carboxyphenoxyethane, optionally with a monocarboxylic acid such as pivalic acid, with one or more glycols, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol , Neopentylglykol and 1,4-Cyclohe-xandimethanol, can be obtained. Biaxially oriented and hot-fixed polyethylene terephthalate films are particularly suitable for producing the photographic films according to the invention. Such self-supporting plastic films can be transparent and translucent, optionally they can be photographically inert dyes, e.g. Blue dyes for X-ray films contain 45 or they can be made opaque by adding additives such as pigments and fillers, in particular they can have a white and paper-like texture, which can be achieved by adding suitable fillers and / or by creating pores can. The white, paper-like film can be used as the basis for photographic prints.

Particularly suitable alkyl ester comonomers are ethyl acrylate and methyl methacrylate, which have good primer layer material properties when they are copolymerized with one another or with other comonomers. 55 The epoxy group of the glycidyl methacrylate and glycidyl acrylate monomers has a crosslinking effect on the copolymer of the intermediate layer and thus forms a barrier against the penetration of organic solvents, which could weaken or destroy the bond between the intermediate layer and the carrier film 60.

A further increase in crosslinking can be achieved by the presence of a hydrophilic acrylic or methacrylic comonomer in conjunction with glycidyl acrylate and / or glycidyl methacrylate, since the hydrophilic group can crosslink with the Ep-65 oxy group of glycidyl methacrylate or glycidyl acrylate and thus to the barrier properties of the layer contributes. Suitable monomers are hydroxyethyl methacrylate and Y-methacryloxypropyltrimethoxysilane, which in aqueous

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dium under. Introduction of functional hydroxyl group solutions. Such pretreatments can be drolyzed. be connected to having a solution on the surface

Another suitable comonomer for making a coating which has a swelling, dissolving or oxidizing undercoat copolymer with barrier properties against the film. Alternatively or in addition, the penetration of solvents is acrylonitrile. 5 the film of a treatment with a corona discharge, with

Expose using flames or UV light using acrylic and methacrylic comonomers. If the plastic ionic character, e.g. the acetate salt of dimethylamino film is a linear polyester, e.g. Polyethylene terephthalate is, noethyl methacrylate, the copolymer can be antistatic egg, the pretreatment can be associated with the fact that properties are given. Applies material on its surface that has a swelling or dissolving effect on the film, which is particularly suitable or dissolving for the use according to the invention, for example a primer layer copolymers consist of 3 mol% to solution of p-chloro-m-cresol, 2.4 -Dichlorophenol, 2,4,6- or 25 mol% glycidyl methacrylate or glycidyl acrylate, 1 mol% 2,4,5-trichlorophenol or 4-chlororesorcinol or a mixture up to 60 mol% acrylonitrile and 35 mol% up to 95 mol % of at least such materials in an ordinary, organic solution of another comonomer of acrylic acid and / or measuring medium, such as acetone or methanol. If desired, thacrylic acid and / or derivatives of these acids, e.g. from acrylic, the pre-treatment solution is a polymeric component, e.g. contain and / or methacrylic acid ester (esters) and / or from a copolymer of vinyl chloride and vinyl acetate. After acrylic or methacrylic monomer with a functional Grup application of such a solution on the film surface can pe, especially from hydroxyethyl methacrylate. Preferably they are dried at elevated temperature for a few minutes, such copolymers contain 5 mole% to 10 mole% glycidyl before the interlayer composition is applied. Old methacrylate or glycidyl acrylate, 1 mol% to 5 mol% hydratively, the plastic film can carry an adhesion-accelerating, oxyethyl methacrylate, 1 to 40 mol% acrylonitrile and 50 to 80 polymeric layer to which the layer is applied. % Acrylic acid and / or methacrylic acid ester. One particular that contains the polymeric component. Suitable layer or interlayer copolymers of this group include Polymers and copolymers of acrylic acids and consists of 7 mol% glycidyl methacrylate, 1 mol% hydroxy methacrylic acids and their esters and copolymers of vinyl-ethyl methacrylate, 35 mol% ethyl acrylate, 21 mol% methyl 25 denchloride.

methacrylate and 36 mol% acrylonitrile. This is an example of The primer layer composition can, according to all known, a copolymer in which the total molar amounts of acrylic acid coating processes, e.g. by hot upsetting, pearling

and methacrylic acid derivatives make up 100 mol%. Layering, reverse roll coating or wide slot coating

The copolymeric undercoat layer may be conventional layering and in the form of an aqueous latex or an aqueous

Additives such as adhesion accelerators, e.g. a partially hygenic solution or a solution in an organic solution

drolyzed vinyl acetate-vinyl chloride copolymer, optionally applied under medium.

Addition of a chlorinated phenol, lubricant and antistatic agent if the film contains a molecular orientation method. is made what is normally done by stretching in

If desired, can be achieved in the coating dispersion or in one or more directions, then a suitable solution is to contain a crosslinking agent which, by crosslinking, applies the copolymeric primer layer during the heart of the primer layer copolymer, its adhesion to the position of the film. Oriented films are generally improved in plastic films. The crosslinking agent should be biaxially oriented by being capable of lowering it in two directions, in addition to internal crosslinking, to stretch in right directions, e.g. to provide protection against the penetration of solvents in the case of polyethylene tereen. phthalate films is the case. Suitable crosslinking components can be coated with epoxy resin before starting the process of stretching, alkyd resin, amine derivatives such as hexamethoxymethyl kung, or, which is preferred, between the two melamine and / or condensation products of an amine. e.g. Drawings carried out perpendicular to one another. In front of melamine, diazine, urea, cyclic ethylene urea, preferably one applies such a coating sequence between cyclic propylene urea, thiourea, cyclic ethylene - the stretching operations in the coating of lenthiourea, alkylmelamines, arylmelamines, benzoglylene-oriented polyamine. In the case of a sol-anamine, guanamine, alkyl guanamine and aryl guanamine operation, the primer layer is preferably coated internally with an aldehyde, e.g. with formaldehyde. So form of an aqueous dispersion is applied.

e.g. the condensation product of melamine with formaldehyde The treatment by corona discharge can be used in air at. The condensation product can, if necessary, alkoxylate atmospheric pressure with the usual equipment using

be. The crosslinking agent can be used in amounts of up to 25 50 times a high-frequency high-voltage generator, preferably

% By weight, based on the weight of the polymer, is generally used with a power output of 1 to 20 kW for a layer of coating. Potential from 1 to 100 kV can be carried out. Geeijgneter-

Preferably, a catalyst is also used to wise discharge is carried out by lightening the film via crosslinking. Preferred catalysts for the dielectric back-up roll at the relief point crosslinking of melamine formaldehyde include Ammonium- 55 at a linear speed of preferably 1.0 to chloride, ammonium nitrate, ammonium thiocyanate, ammonium- 500 m / min. The discharge electrodes can be dihydrogenphosphate, ammonium sulfate, diammonium hydrogen at a distance of 0.1 mm to 10.0 mm from the gene phosphate, p-toluenesulfonic acid, maleic acid, through the reactive surface of the moving film. After the betion stabilized with a base, and morpholinium p-toluenesulfonation with a corona discharge should be applied. 60 primer layer, preferably a wetting test value

The copolymeric undercoat layer may have during that measured by the standard wetting test of

Production of the plastic film or afterwards on the plastic union carbide (WC 81-3 / 1964) with a mixture of form

foil are applied. amide and «Cellosolve», 56 dynes / cm, while one

If the layer is generally subjected to a wetting test value after the production of the untreated plastic film, the film can be pretreated 65 in a manner between 35 and 45 dynes / cm. In this test, or are coated to ensure the adhesion of the layer to the surface using various concentrates of form

the film surface is improved. To modify this amide in «Cellosolve» (2-ethoxyethanol) liquid mixtures

Surface can be prepared and applied to chemical or physical pretreatment with different surface tensions

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painted the surface to be examined. The wetting test value is the surface tension of the liquid mixture, which has the highest surface tension of the mixtures, which do not contract into droplets within 2 s after being brushed onto the surface.

Adhesion was satisfactory for copolymeric primer layers with a layer weight in the range from 0.1 mg / dm2 to 10 mg / dm2. Layer weights in the range from 1.0 mg / dm2 to 3.0 mg / m2 are preferred.

The copolymeric primer layers applied to a polyethylene terephthalate film by the process according to the invention make the film base suitable for recycling by the film-forming extruder and the stretching device.

All suitable, light-sensitive silver halide emulsions can be applied to the modified surface of the primer layer by known methods. Such an emulsion can contain the known additives. The invention is explained in more detail by the following examples, dry adhesion and wet adhesion being defined and estimated as described below.

Dry adhesion refers to the adhesion of a gelatinous silver halide emulsion to the plastic film in the finished photographic film. Dry adhesion, before and after processing the film in standard photographic chemicals, was estimated by sticking a self-adhesive tape along the tear edge of the film and quickly removing the tape from the film.

Wet adhesion

Refers to the adhesion of a gelatinous silver halide emulsion to the plastic film in the finished photographic film over a gelatinous primer layer, if any, under the emulsion. Wet adhesion was assessed by processing the film in standard photographic chemicals, washing in water for 15 minutes, and then rubbing with a sponge over a series of lines that had been scored in the still wet emulsion.

example 1

A primer layer was made from the following monomer mixture:

36 mole% ethyl acrylate 29 mole% methyl methacrylate 8 mole% glycidyl methacrylate 2 mole% hydroxyethyl methacrylate 25 mole% acrylonitrile

600 ml of water, 20 g of an emulsifier commercially available under the name "GAFAC" RE610, 2 ml of dimethylamino-ethanol, 0.6 ml of lauryl mercaptan to control the molar weight, 10% by weight of the total monomer content and 25% by weight % of the total catalyst content was placed in a flask, degassed, stirred and heated to a polymerization temperature of 60 ° C. under an inert atmosphere. The total volume of the monomers was approximately 600 ml and the total volume of the catalyst was 300 ml in the form of a 0.1% by weight aqueous solution of potassium persulfate. After the reaction had progressed for 30 minutes, the remaining monomers and an additional 55% by weight of the catalyst were added over a period of about 3 hours. The resulting latex was stirred for a further 15 minutes, the remaining 20% by weight of the catalyst was added and the batch was stirred for a further 15 minutes before being emptied. The latex was freed from residual monomers by evaporation under partial vacuum.

This mass was diluted until 3.5% by weight solids content s had been reached and 0.5% by volume of a nonionic, surface-active agent, commercially available under the name “Lissapol” N, were added.

A polyethylene terephthalate film was extruded from the melt and rapidly cooled on a cooled, rotating drum, the film becoming amorphous. The resulting film was stretched slightly 3.5 times the original length in the extrusion direction. Then, the film was coated on both sides with the above-described aqueous dispersion by a roll application method and transferred to a stenter drying oven, where the coating was dried. The dried, coated film was then stretched in the lateral direction to about 3.5 times the original width and finally heat-set at a temperature of 210 ° C. The final thickness of the primer 20 layer on each side of the biaxially stretched film was about 0.3 | xm and the total thickness of the film was about 100 | xm.

The copolymeric primer layer was treated with a corona discharge at atmospheric pressure using a treatment device commercially available under the name "Vetaphone" with a power output of 3 kW. The coating thus obtained had a wetting test value, measured by the Union Carbide method, which was greater than 56 dynes / cm. The following conditions were observed during the treatment with corona discharge: throughput speed 6.10 m / min, power 2 kW, 1.5 mm distance between electrode and foil.

A common photographic silver halide emulsion for X-rays was applied directly to the corona-treated surface of the undercoat layer without interposing an intermediate layer of gelatin. The adhesion of the wet and the dry emulsion was satisfactory.

40 Example 2

A customary biaxially oriented, clear polyethylene terephthalate film with a thickness of 100 mm was pretreated with the following solution:

45 5 g p-chloro-m-cresol

1 g of a copolymer of vinyl acetate and vinyl chloride,

commercially available under the name VAGH 100 ml acetone.

The solution was applied to the film, giving a layer weight of 100 mg / dm2 for the wet layer, and dried at 80 ° C. for 2 minutes.

The following primer layer was applied to the pretreated surface:

55

5 g of a carboxy-modified acrylic polymer, commercially available under the name "Hycar" 2671, 95 g of distilled water.

6o The coated film was dried for 3 minutes at 80 ° C., the layer weight of the dry polymeric primer layer thus obtained was 2 mg / dm2.

The film was split into two parts, A and B.

65 Part A

A common gelatinous silver halide emulsion for X-rays was applied directly to the copolymer layer that had not been corona treated

5

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and chilled to gel the coating and dried at 35 ° C for 20 minutes.

Then the adhesion property of the silver halide emulsion was checked. The dry adhesion was good, but the wet adhesion was very poor and the emulsion could be removed by rubbing.

Part B

The copolymeric primer layer was corona treated using the device and conditions described in Example 1.

Finally, the treated film, like part A described above, was coated with a gelatinous silver halide emulsion for X-rays.

Then the adhesion of the photographic material was checked. The dry adhesion before and after processing was excellent, and the wet adhesion during processing was excellent.

Example 3

A common, biaxially oriented, clear polyethylene terephthalate film, 100 Jim thick, which had been precoated with a crosslinked copolymer formed from 45% by weight of ethyl acrylate, 50% by weight of methyl methacrylate and 5% by weight of methacrylamide was applied a primer layer solution with the following components:

3 g of a copolymer of ethyl a-chloroacrylate / ethyl

Acrylate / itaconic acid (60 mol% / 35 mol% / 5 mol%) 100 ml acetone on the precoat with a primer coat.

The copolymeric undercoat layer was treated with a corona discharge using the device and conditions described in Example 1, then a common photographic emulsion consisting of gelatinous silver halide was applied to the treated surface.

The dry and wet adhesion of the applied emulsion was satisfactory.

Example 4

The procedure of Example 1 was followed by stretching a polyethylene terephthalate film and coating the film with a primer layer composition which had the following composition:

10 g of a carboxy-modified acrylic polymer, commercially available under the name «Hycar» 260 X 84, 90 g of distilled water,

repeated.

The polymeric undercoat layer was treated with a corona discharge in accordance with Example 1 and coated with a common photographic emulsion consisting of gelatinous silver halide. The emulsion was subjected to accelerated aging at 50 ° C and 67% relative humidity for 16 hours before the adhesion test. The wet and dry adhesion of the emulsion was satisfactory.

Example 5

s The procedure of Example 1 was followed by stretching a polyethylene terephthalate film and coating the film with a primer layer composition consisting of the following:

10 g of an acrylic / vinyl chloride copolymer, commercially available under the name “Geon” 450 X 20, 90 g of distilled water,

repeated.

15 The copolymeric undercoat layer was treated with a corona discharge in accordance with Example 1 and coated with a common photographic emulsion containing gelatinous silver halide. The wet and dry adhesion of the emulsion was excellent.

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Example 6

Example 5 was repeated, with the difference that the primer layer composition was composed as follows:

10 g of an acrylic / acrylonitrile / styrene copolymer (Morton Williams Limited), commercially available under the name AA421 90 g of distilled water.

When the film was processed manually and also in customary solutions for use in automatic processing apparatus, the emulsion applied in this way showed excellent wet and dry adhesion.

Example 7

Example 3 was repeated, except that the primer layer composition was composed as follows:

40 3 g of a chloroacrylonitrile / ethyl acrylate / itaconic acid copolymer (60 mol% / 35 mol% / 5 mol%), 100 ml acetone.

A customary X-ray emulsion consisting of gelatinous silver halide was applied to the copolymeric primer layer treated with a corona discharge. The wet and dry adhesion of the emulsion was good.

50 Example 8

Example 5 was repeated, with the difference that the primer layer composition contained the following constituents:

10 g of an ethyl acrylate / methyl methacrylate / itaconic acid 55 / styrene copolymer latex (28.5 mol% / 28.5 mol% / 5

Mol% / 38 mol%),

90 g distilled water

A common photographic silver halide emulsion for X-rays was applied to the copolymeric undercoat layer treated with a corona discharge.

C.

Claims (8)

633 640 PATENT CLAIMS 1. A process for producing a photosensitive photographic film, characterized in that the surface of a self-supporting plastic film is coated with a primer comprising a copolymer consisting of 57-100 mol% of one or more monomers selected from glycidyl acrylate and methacrylate, methyl, ethyl, propyl, isopropyl, butyl, hexyl, heptyl, n-octyl, 2-ethylhexyl acrylate and methacrylate, halogen-substituted acrylate and methacrylate, acrylic and methacrylamide, N-methyl, N-ethanol, N-propanol-acrylamide, N-methylol, N-ethanol methacrylamide, N-methyl-acrylamide, N-tert-butyl-acrylamide, acrylonitrile, halogen-substituted acrylic and meth acrylonitrile, hydroxyethyl methacrylate, y-methacryloxypropyl trimethoxysilane, dimethylaminoethyl methacrylate, and 0-43 mol% of one or more monomers selected from styrene, butadiene, vinyl chloroacetate, benzoate, pyridine, chloride, vinylidene chloride, Maleic and itaconic acid and their appendix ydriden, the surface of the applied primer layer is subjected to a modification treatment by corona discharge and light-sensitive silver halide emulsion layer is applied directly to the surface of the primer layer thus modified, with the proviso that when the copolymer of the primer layer consists of 100 mol % of the former group of monomers, this copolymer is derived from at least two of these monomers 2. The method according to claim 1, characterized in that a copolymer is used for the primer layer, which is derived from ethyl acrylate and methyl methacrylate. 3. The method according to any one of the preceding claims, characterized in that a copolymer is used for the primer layer, the 3-25 mol% glycidyl methacrylate or acrylate, 1-60 mol% acrylonitrile and 35-95 mol% of at least one other comonomer selected from acrylic and / or methacrylic acid and / or from a derivative of these acids. 4. The method according to any one of the preceding claims, characterized in that a copolymer is used for the primer layer, which is composed of 7 mol% glycidyl methacrylate, 1 mol% hydroxyethyl methacrylate, 35 mol% ethyl acrylate, 21 mol% methyl methacrylate and 36 mol% acrylonitrile. 5. The method according to any one of the preceding claims, characterized in that the primer is applied to this film during the production of the plastic film. 6. The method according to claim 5, characterized in that the plastic film is biaxially oriented by stretching in two mutually perpendicular directions, and in that the primer is applied between the stretching operations in the two directions. 7. The method according to any one of the preceding claims, characterized in that a biaxially oriented, heat-set polyethylene terephthalate film is used as the plastic film. 8. A light-sensitive photographic film produced by the method of claim 1. It is widely recognized in the photographic art that a photosensitive photographic emulsion applied directly to the surface of a plastic base sheet does not adhere sufficiently to the base sheet for most of the usual photographic uses. It has therefore become common practice to insert two or more intermediate layers between the base film and the photographic emulsion. For example, if the photographic emulsion consists of a gelatinous silver halide mass, first apply a polymeric intermediate layer to the surface of the carrier film and then a gelatinous intermediate layer before coating the gelatinous intermediate layer with the photographic emulsion.