DE941764C - Photographic films and methods of making them - Google Patents

Description

The invention relates to photographic films having a novel substrate. In particular, it relates to photographic films comprising a hydrophobic support, a substrate consisting of a mixture of a solvent-soluble polyester and an organic polyisocyanate or an organic polyisothiocyanate, and at least one water-permeable colloid layer. The invention also encompasses the methods of making these films.
According to the invention, new methods for anchoring water-permeable, colloidal silver salt emulsions on hydrophobic carriers are created, it being possible to use the apparatus commonly used in phototechnology for applying coatings. The methods according to the invention are simple and yet effective and result in a solid anchoring of a colloidal silver salt emulsion on a hydrophobic carrier film, both in the wet and in the dry state. A further object of the invention is to achieve ao firm anchoring on carrier films made of polyethylene terephthalic acid ester.

It has been found that a colloidal silver salt emulsion layer can be firmly anchored on a hydrophobic orientable polyester carrier film by first applying a solution of a mixture of i. a polyester of a glycol and terephthalic acid with a molecular weight of over 5,000, which is at least ^{1 to} ₂ percent by weight soluble in trichlorethylene, and of 2. an organic polyisocyanate or an organic polyisothiocyanate including diisocyanate dimers. The second component can make up to 50 percent by weight of the solid substances contained in the coating solution.

The mixture of the polyester and the polyisocyanate or polyisothiocyanate can be applied to the orientable polyester base from an approximately ¹ _{I 2} to 25 or more percent by weight solution in a suitable non-reactive solvent, e.g. B. a chlorinated hydrocarbon applied. The solvents should be volatile. Preferred solvents are methylene chloride, trichlorethylene, carbon tetrachloride, etc. After the layer is dried, a thin substrate of a water-permeable colloid and then a water-permeable colloidal silver salt emulsion layer is applied. Although the application of the water-permeable colloid substrate is expedient, it can also be omitted if necessary, since a colloidal silver salt emulsion layer alone already firmly adheres to the layer consisting of the mixture of the polyester with the polyisocyanate or polyisothiocyanate. The water-permeable colloid can be gelatin, polyvinyl alcohol, a partially hydrolyzed polyvinyl acetate or chloroacetate, a polyvinyl acetal or a cellulose derivative, all of the compounds mentioned having a hydrophilic character.

Polyesters suitable for use in the blends for making the intermediate layer and are sufficiently soluble in trichlorethylene can be obtained by condensation of a mixture of 1. one Polymethylene glycol with 2 to 10 methylene groups and 2. a polyethylene glycol with 1 to 5 oxyethylene radicals with terephthalic acid or an acid chloride or bromide thereof or one Diesters of terephthalic acid with an alkanol with ι to 6 carbon atoms can be obtained. the Amount of polyethylene glycol in the polymethylene glycol-polyethylene glycol mixture can be 20 to 100 and preferably 25 to 75 mole percent.

Other suitable polyesters are by condensation of a polymethylene glycol with two to ten Methylene groups with a mixture of 1. terephthalic acid or an acid chloride or bromide or a diester thereof with an alkanol with 1 to .6 carbon atoms and 2. a saturated aliphatic dicarboxylic acid with 4 to 16 carbon atoms or an acid chloride or bromide or a diester thereof with an alkanol with 1 to 6 carbon atoms obtained. Preferred aliphatic Are dicarboxylic acids; Adipic acid, sebacic acid and azelaic acid and their acid chlorides and -bromides and their dimethyl and diethyl esters. The polyester formation can be based on the in the previous paragraph the manner described.

In the described polyester group the polymethylene glycol in excess is to be present and make up at least terephthalic 25 ° / ₀ of the total acids. The aliphatic dicarboxylic acid can make up 10 to 75% of the total acid. In addition to these two compounds, 1 to 25% of another dicarboxylic acid can also be present, which can form a polyester by condensation. These last-mentioned dicarboxylic acids include, inter alia, dibenzoic acid, phthalic acid, isophthalic acid and their dimethyl and diethyl esters.

Many known organic polyisocyanates and polyisothiocyanates can be used for the invention Procedures are used. These compounds contain two or more - N = C = Y groups, where Y is oxygen or sulfur. The easier accessible compounds contain 2N = C = Z groups, where Z is a chalcogen with an atomic weight below 33. Although the connections in which a hydrocarbon radical is attached to the - N = C = Y groups, are preferred, can also the diisocyanate dimers, which contain a uretidinedione or a 1,3-oxacetidene ring, be used.

Although the invention can be applied to any cold-stretchable, orientable polyester, including those described in US Pat microcrystalline, cold-stretchable, linear, high-polymer ester of terephthalic acid with glycols of the series H0 (CH ₂ ) n0H, where η is an integer between 2 and 10. These compounds are known from U.S. Patent 2,465,319.

Any conventional method can be used to apply the layer consisting of the mixture of the solvent-soluble polyester and the polyisocyanate or polyisothiocyanate to the surface of the carrier film. The layer can e.g. B. applied from a funnel or painted on, the surface of the film passes under a roller and comes into contact with the surface of the liquid, it can also be rolled on, sprayed on or the like. Be. Here, squeegees etc. can be used to remove excess liquid. After the intermediate layer has been applied to one or both surfaces of the filmstrip, it is ^{dried by heating to 50 °} or less to 150 ^° or higher. During the drying process, a stream of air can be passed over the coated surface.

The invention is illustrated by the following examples iao explained in more detail, but without being limited thereto. Parts and percentages are given by weight.

Example I.

A polyester was made by heating dimethyl terephthalate with a stoichiometric excess

shot of diethylene glycol to 170 to 220 ⁰ in the presence of 0.03 percent by weight lead oxide, based on the terephthalic acid dimethyl ester. The heating continued until no more methanol evolved. Then, the temperature was increased to 250 to 280 ⁰ lowers and the pressure to 0.1 to 0.5 mm Hg. As the polymerization proceeded, diethylene glycol evolved. The polyester obtained was clear, soft and pliable after cooling to room temperature and had a true viscosity of 0.64 in a mixture of 40 parts by volume of phenol and 60 parts by volume of tetrachloroethane.

A 4 ° / ₀ solution of the thus obtained polyester in methylene chloride containing 25 percent by weight of methylene-bis (based on the polyester) (4-phenyl isocyanate) was added, was then coated onto a piece of 0.1 mm, applied biaxially stretched polyethylene terephthalic acid ester film. After drying, a gelatin layer was applied to the polyester diisocyanate surface from the following dispersion:

Gelatin 1%

_a5 acetic acid 4%

Methanol 40%

Acetone 55%.

The film was dried at 100 ° for 5 minutes and coated with a gelatin silver bromide iodide emulsion, which is 4.9% of a mixture of 98.44% Containing silver bromide and 1.56% silver iodide. The silver halide was dispersed in gelatin (6.2% by weight of the entire emulsion). After drying, the adhesive strength was the emulsion layer on the carrier film good.

The film carrying this gelatin-halosilver layer was developed for 5 minutes at 21 ^° C. in the following solution:
40

N-methyl-p-aminophenol sulfate ... 5.0 g

Hydroquinone 31.4 g

Sodium sulfite 151.0 g

Potassium carbonate,. ^IO 4.3 g

Sodium hydroxide 6.6 g

Potassium bromide 11.7 g

Water except for 4 1.

The developed film was then rinsed in water for 5 minutes and then immersed in a fixing bath of the following composition ^{at 21 ° C. for 10 minutes:}

Sodium thiosulf at 350 g

Sodium sulfite 15 g

Sodium acetate 18 g

Potassium aluminum sulfate 32 g

Citric acid 8 g

Water except for I 1.

The film was finally washed in water for another 10 minutes, whereupon it gave a good wet and dry finish Possessed dry adhesive strength.

Example II

A photographic film was prepared, exposed and treated as in Example I, only with the Exception that instead of the polyester of Example I, a polyester was used which one by reacting equimolar amounts of dimethyl terephthalate and adipic acid with ethylene glycol received.

Example III

A photographic film was produced, exposed and processed as in Example I, only with the modification that instead of the polyester of Example I, a polyester was used which is obtained by reaction of dimethyl terephthalate with a mixture of 40 mol percent ethylene glycol and 60 mole percent diethylene glycol was obtained. The wet and dry adhesion strengths were good.

Example IV

A photographic film was made, exposed and treated as in Example I, with the exception that instead of the polyester of Example I, a polyester was used which is obtained by reaction equimolar amounts of dimethyl terephthalate and sebacic acid with ethylene glycol received. The wet and dry bond strengths were similar.

Example V Example VI

A photographic film was produced, exposed and processed as in Example I, only with the modification that a reaction of dimethyl terephthalate, dimethyl dibenzoate and Azelaic acid (40: 20: 40 mol percent) polyester obtained with ethylene glycol instead of the polyester of Example I was used. The wet and dry bond strengths were similar.

A photographic film was made, exposed and treated as in Example I, with the exception that instead of the polyester of Example I, a reaction of dimethyl terephthalate, Dimethyl isophthalate and sebacic acid (50: 25: 25 mol percent) obtained with ethylene glycol Polyester was used. The results were similar.

Example VII " ⁵

The whole procedure of Example II was obtained again _7, but with the difference that the carrier was not biaxially stretched. The wet and dry adhesion strengths were good.

Example VIII

Example II was repeated, except that there was no gelatin intermediate layer on the carrier film, but the gelatin-halosilver layer is applied directly to the carrier

became. The wet and dry bond strengths were sufficient, but not quite as good as in Example I.

Example IX 5

Example II was repeated, with the exception that 2,4-toluene-2,4-diisocyanate was used instead of methylene-bis (4-phenylisocyanate). The results for bond strength were similar, 10

Example X

Example II was repeated, the only difference being that instead of methylene bis (4-phenyl isocyanate) the dimer of toluene-2,4-diisocyanate was used. The results regarding the adhesive strength were similar.

Example XI

A 4% solution of the polyester from Example II in methylene chloride, which contains 25% methylene bis (4-phenyl isocyanate), based on the polyester, was based on the biaxially stretched polyethylene terephthalic acid ester film upset. After drying, a layer of the US Pat 2 513190 known mixed m- (Benzoylacetamido - benzaldehyde - sodium - ο - sulfobenzaldehyde polyyinyl acetals applied in the following solvent mixture:

Acetal 5%

Methanol 16%

Water 79%

After drying at 50 °, the following solution was applied:

Mixed m- (Benzoylacetamido) -benzaldehyde-sodium-o-sulfobenz-

aldehyde polyvinyl acetal '.. 1.5%

Boric acid: 1.9%

Diisopropanolamine 1.3%

Acetone .. 40.0%

. 95% ethyl alcohol 55.3%.

The film was made at. 50 ° dried and heated to 100 ° for 2 minutes. Then he was using a polyvinyl acetal - Color former - silver salt - dispersion coated, which 1.5 percent by weight of a mixture of about 1.3% silver iodide and 98.7% silver bromide contained in the polymeric color former (3.8 weight percent of the entire emulsion) was dispersed. The color former is from the USA patent 2,513,190 known. After drying at 24 ° C the emulsion adhered well to the support. The film was exposed and treated in the following solutions:

i. Developer (10 minutes at 20 ^° C.):

p-aminodiethylaniline hydrochloride 2.5 g

Sodium sulphate .. 10.0 g

Sodium carbonate 46.8 g

Potassium bromide 2.0 g

Water except ... 11.

2. Water rinse for 30 seconds.

3. Fixing bath 5 minutes at 20 '

Sodium thiosulfate

Sodium sulfite

Sodium tetraborate

Glacial acetic acid ■ .. ·

Potassium aluminum sulfate

Water except for

4. Water rinse for 5 minutes.

5. Bleach 5 minutes at 20 ⁰ C.

Potassium ferricyanide

Boric acid

Sodium tetraborate

Water except for

6. Water rinse for 5 minutes.

7. Fixing bath 5 minutes at 20 ° C.

Sodium thiosulphate .... »

Water except for

8. Water rinse for 10 minutes.

C.

240 G 15th cn? 18th G 12th ecm 20th cn? 3 1. 100 cn? IO G 5 G I. 1. 200 G I. 1.

The invention explained above is not restricted to the polyisothiocyanates or polyisocyanates mentioned in the examples. Many compounds are known as well. These include polymethylene diisocyanates and diisothioeyanates, e.g. B. ethylene diisocyanate, trimethylene diisocyanate, dodecamethylene diisocyanate, hexamethylene - diisoeyanate, tetramethylene - diisoeyanate, pentamethylene diisocyanate, and the corresponding diisothioeyanate, alkylene diisocyanate and diisothioeyanate, z. B. propylene-i, 2-diisocyanate, 2,3-dimethyltetramethylene-diisocyanate and -diisothioeyanate, butylene-i, 2-diisocyanate, butylene-i, 3-diisothioeyanate and butylene-i, 3-diisocyanate; Alkylidene diisoeyanates and diisothioeyanates, e.g. B. ethylidene diisoeyanate (CH ₃ CH (NCO) ₂ ) and heptylidene diisothioeyanate (CH ₃ (CH ₂ ) ₅ CH (CNS) ₂ ); Cycloal- ioe kylen-düsoeyanate and -diisothioeyanate, z. B. i, 4-diisocyanatocyclohexane, cyclopentylene-r, 3-diisocyanate and cyclohexylene-i, 2-diisothiocyanate; aromatic polyisocyanates and polyisothiocyanates, ζ. Β. m-phenylene diisocyanate, p-phenylene diisocyanate, p-phenylene diisothiocyanate, i-methyl-phenylene-2,4-diisocyanate, naphthylene-1,4-diisocyanate, o, o'-toluene diisocyanate, diphenyl-4,4'- diisothiocyanate and diisoeyanate, benzyl-i, 2, 4-triisothio'cyänat, 5-nitroi, 3-phenylene diisocyanate, xylylene-i, 4-diisocyanate, xylylene-i, 3-diisocyanate, 4, 4'-diphenylene methane diisoeyanate, 4,4'-diphenylene propane diisocyanate and xylylene-1,4-diisothiocyanate; aliphatic-aromatic diisocyanates and diisothioeyanates, e.g. B. phenylethylene diisocyanate (C ₆ H ₆ CH (NCO) CH ₂ NCO); Diisocyanates and diisothioeyanates containing heteroatoms, e.g. B.

SCNCH ₂ OCH ₂ NSc, SCNCH ₂ CH ₂ OCH ₂ Ch ₂ NSC, and SCN (CH ₂ ) ₃ -S- (CH ₂ ) ₃ NSC; 1, 2, 3, 4-tetraisoeyanatobutane, butane-i, 2,2-triisocyanate, i-isocyanato-4-isothiocyanatohexane and 2-chloro-1,3-diisocyanatopropane. Mixtures of two or more of these compounds can also be used. These compounds are more reactive when the coated film is heated to an elevated temperature, e.g. B. 150 ⁰ , is heated.

Have the preferred diisocyanates, diisothiocyanates, and mixtures of isocyanates and isothiocyanates the general formula ZCN — RNCZ, in where R is a divalent hydrocarbon radical and Z is a chalcogen with an atomic weight below 33 means.

Instead of those described in the previous examples colloidal silver salt emulsions can be applied to those containing the diisocyanate compounds Layer also other colloidal silver salt emulsion layers and water permeable colloidal ones, none light-sensitive silver salts containing intermediate layers are applied. Other colloids, which according to the invention can be anchored on the carrier film are: polyvinyl alcohols and water-soluble polyvinyl alcohol derivatives very generally, e.g. B. partially hydrolyzed polyvinyl acetates and mixed Polyvinyl chloride acetates, hydrolyzed copolymers of vinyl acetate with unsaturated compounds, z. B. maleic anhydride, acrylic acid ester, etc. Suitable colloids of the last mentioned Art are known from U.S. Patents 2,276,322, 2,276,323 and 2,397,866. And others Colloids are hydrophilic, partially substituted polyvinyl esters and acetals and the low-substituted ones Cellulose esters of saturated aliphatic monocarboxylic acids with 2 to 4 carbon atoms and low-substituted ones Cellulose ethers, e.g. B. methyl cellulose, ethyl cellulose, etc. Other natural colloids are including casein, albumin, gum arabic, agar-agar, polyglycuronic acid, etc., which with the help of the substrates according to the invention can also be anchored on the carrier tabs.

On color films for multicolor photography, three differently sensitized colloidal Silver salt emulsion layers are applied one on top of the other, which contain color formers. It can also colloidal color formers are used as binders for the halogen silver. These layers are supposed to be arranged that way and be sensitized to receive light of different colors of the visible spectrum. The color formers can, for. B. be selected so that they are yellow, blue-green (cyan) and magenta-colored quinonimine or azomethine dyes and the like in the corresponding layers result, such as this is common in color photography and is known, for example, from US Pat. No. 2,397,864 is. Filter dyes can be in one or more of the above color former layers or in a separate one Shift be present, namely z. B. a polyvinyl alcohol or equivalent layer, which has a hydroxyl polymer. Usually a yellow filter dye is used in one layer used, which extends over the two sides of the film facing the camera the most distant photosensitive layers.

The intermediate layers according to the invention can be used in black and white films as well as in color films for cinematography and conventional photographic, for portrait films, for holding documents for lithographic, industrial and medical X-ray films, etc. find use.

An advantage of the invention is the creation of a simple and economical method for Application of substrates to carrier films. Another advantage is that the intermediate layers according to the invention a good and sufficient anchoring between the carrier and effect of a colloidal silver halide emulsion layer. This advantage is especially useful with movies with a polyethylene terephthalic acid ester base is important. Another benefit lies in the same good anchoring when the mixture is applied to both an oriented and a non oriented film. Further advantages emerge from the above description. The invention can experience further changes without going beyond its scope.

Claims (12)

Patent claims: 1. Photographic film, characterized by a hydrophobic, molecularly orientable polyester carrier film, which on at least one side has a substrate consisting of a mixture of at least ¹ J ₂ percent by weight in trichlorethylene-soluble polyester of a glycol and terephthalic acid with a molecular weight of more than 5000 and an organic polyisocyanate or organic polyisothiocyanate and carries a water-permeable colloid layer. 2. 'Film according to claim 1, characterized by a water-permeable * colloid layer on the Substrate and a water-permeable silver salt colloidal emulsion layer on the colloid layer. 3. Film according to claim 1 or 2, characterized in that that the carrier film consists of polyethylene ■ terephthalic acid ester. ' 4. Film according to claim 1, 2 or 3, characterized in that that the organic polyisocyanate contained in the substrate is a polymethylene isocyanate having 2 to 12 carbon atoms. 5. Film according to claim 1, 2 or 3, characterized in that .that the organic polyisocyanate contained in the substrate is a diisocyanate of a aromatic hydrocarbon. 6. Film according to claim, characterized in that that the diisocyanate present in the substrate is methylene bis (4-phenyl isocyanate). 7. Film according to claim 5, characterized in that the diisocyanate present in the substrate Is toluene-2,4-diisocyanate. 8. Film according to one of the preceding claims, characterized in that the water-permeable Colloid layer is a gelatin-halosilver emulsion layer. 9. Photographic film according to one of claims ι to 7, characterized in that a gelatin layer over the substrate and over this a gelatin-halosilver emulsion layer is located. 10. Process for the production of photographic films according to Claims 1 to 9, characterized in that that one or more A layer-forming mixture is applied to surfaces of a hydrophobic orientable polyester carrier film, which consists of a ^{polyester, soluble to at least 1} ₂ % by weight in trichlorethylene, made of a glycol and terephthalic acid with a molecular weight of more than 5000 and an organic polyisocyanate or polyisothiocyanate, whereupon the layer obtained is dried and covered with a water-permeable colloid layer. 11. The method according to claim 10, characterized in that the drying at 50 to 150 ^{0 is} carried out. 12. The method according to claim 10 or 11, characterized characterized in that the water-permeable colloid contains photosensitive silver salts. © 509 691 4.56