DE1547705A1 - Process for the spectral sensitization of photographic light-sensitive materials - Google Patents

Description

May 24, 1966 8 MONKS 22

THIERSCHSTRASSE <TELEPHONE; (0811) 293297

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PATENTANWÄLTE _{25 /} i, o "** *

DR.-ING. WOLFF, H.BARTELS, DR. BRANDES, DR.-iNG. HERO

Eastman Kodak Company, 343 State Street, Rochester, New York State, United States of America

»Process for the spectral sensitization of light-sensitive, photographic materials

The invention relates to a method for spectral Sensitization of light-sensitive photographic materials, especially photographic silver halide demulsions.

Most of the spectral sensitizing dyes for photosensitive materials, such as silicon halide emulsions are known to be very insoluble in water. In many cases, however, it is necessary these water-insoluble dyes are aqueous systems -to be incorporated: like tml "pifcls ;; ei3e phot oji ^ -phl see 311-

i'ii-ViOfi

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play wise gelatin ·. Most of the known spectral sensitizing dyes are so insoluble that their introduction into aqueous systems requires large amounts of organic solvents to dissolve them. However, the introduction of large amounts of organic solvents into hydrophilic colloid systems poses serious problems on. In particular, the coating of photographic substrates with such emulsions is difficult * 9HL

The invention therefore had the object of an improved method for spectral Senslbllisierung light-sensitive photographic materials, particularly photogra- · develop phischer SllberhalogenidemulsIonen, ie a process, we Mies allows to incorporate the light-sensitive photographic materials spectrally sensIbIrisierende water-insoluble dyes, without the need for greater Solvents must be used.

The invention was based on the knowledge that the frame * te problem can be solved by the fact that one is to be sensitized Photographic material comprising a dispersion of a spectral sensitizing dye in one

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add id to form a dispersion.

Surprisingly, it has been shown that the Not only does the sensitization method of the invention obviate the problem of using large amounts of solvent, but that the light-sensitive photographic materials spectrally sensitized by the process of the invention, In particular, silver halide emulsion layers have a lower tendency to fog and higher Sensitivities are sensitized ^ as corresponding photographic materials, according to the previously known Procedures were spectrally sensitized. Another advantage of the method of the invention is that spectrally sensitized photographic emulsions obtained by the process of the invention at high speeds Allow photographic base materials to be coated without coating difficulties caused by their presence larger amounts of organic solvents are to be attributed.

In carrying out the method of the invention, it is preferred to dissolve the spectral sensitizing dye in a solvent with heating. As highly concentrated solutions as possible are expediently prepared. The solution of the dye ocl »": ⁵ if necessary, a solution of several dyes would then include a hydrophilic colloid

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carried, such as an aqueous gelatin solution. The dispersion of the; Dye in the hydrophilic colloid can be facilitated in an advantageous manner by using a dispersing agent Dispersion of the dye in the hydrophilic colloid prior to / addition to the photographic material to be sensitized is milled or homogenized · Preferably is grind or homogenize the dye dispersion in such a way that the dye particles have an average diameter of less than about 1.0 micron

The following examples are intended to further illustrate the process of the invention.

In Examples 1 and 4 the method of the invention is followed described using water-immiscible organic solvents which have such a low Have vapor pressure that they evaporate from the dye dispersion on drying or are easily volatilized can.

example 1

A negatively sensitive gelatin silver bromoiodine demulslon ν was used up to optimal sensitivity with a mixture consisting of a compound with a labile sulfur, atom and a soluble gold salt, whereupon the

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Emulsion was divided into two servings. Both servings were spellrally in the range of 5000 to 6000X spectrally sensitized as follows:

Emulsion a):

A benxothlazolylidene-isopropylidene-oxaxolidinedione-merocyanine dye (dye I), as described in Example 7 of U.S. Patent 2,165,338 was added to one molten portion of the emulsion with vigorous stirring. The concentration of the dye was 0.132 g of dye per mole of silver halide. The dye was added from an acetone solution.

Emulsion b):

For the preparation of this emulsion the same dye was used that was also used for the preparation of the emulsion a) was «The dye (dye I) was however this time in pre-dispersed in an aqueous gelatin solution a dye dispersion made, consisting of:

Dye # 1 0.130 g Acetic acid 3 gtbt Ethyl acetate 70 cm ³

10 aqueous gelatin,

solution 200 cm- ³

5 Jf aqueous solution of a

Alkylnaphthalene sodium sulfo-

nates (Alkane1 B) 75 cm- *

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After drying this dispersion, it became too * the added to another Eaulsionsportion, so then, again 0.132 g There were dyes per mole of silver halide.

A dispersion of a purple dye-forming coupler of the pyrazolone type in a high-boiling solvent was added to both emulsions.

The emulsions were then coated on a conventional photographic support. The films obtained were then Exposed for 1/25 of a second with a 500 watt tungsten lamp in an intensity scale sensitometer, which was set to 2650 ° K had been set. A No. 15 Wratten filter was located between the light source and the film strip. Both films were then produced in the same way using the color negative process Developed as it is described, for example, in the Journal of the Society of Motion Picture and Television Engineers, Volume 61, (1953), pages 667-701, in particular page 683

The following results were obtained:

Awareness 9t Development
duration ReI. Em
pfind
opportunity Minimum.
density according to a 12 minutes 100 0.36 "b 12 · 155 0.12 "a 14 " 79 0.44 "b 14 * 159 0.17 "a 16 " 76 * 0.53 • b 16 " 178 0.24 > y * fr / s ¥ Ψ9 BATH ORIGINAL

It is clear from the results obtained that a considerable increase in sensitivity (over 50 %) is obtained using the sensitization method of the invention. Furthermore, the results obtained indicate that a large reduction in the haze _{value (D n} -) is obtained when the method of the invention is applied »

Similar results are obtained if, for example, TiO ₂ or ZnO are used as the photosensitive material instead of silver halide.

Equally favorable results were also obtained when, instead of gelatin, a cellulose ether phthalate, a polyvinyl alcohol or a polyacrylamide with a combined acrylate group content of 30 to 60 % and a specific viscosity of 0.25 to 1.5 or mixtures of such colloids were used as the hydrophilic colloid .

The method of the invention is also suitable for Sensitization of binder-free silver halide films produced by the deposition of silver halide on a. nem carrier can be produced in a vacuum. '

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Example 2

A negatively sensitive gelatin silver bromoiodide emulsion was prepared with a mixture consisting of a compound with a labile sulfur atom and a soluble gold salt until optimum sensitivity was achieved. The emulsion was then divided into swel portions. Both portions were then optically sensitized in the catfish described below in the range from 5000 to 6000 X as follows:

Emulsion c):

With dye I as described in Example 1 (a).

Emulsion d):

First, a dye dispersion was prepared with the following composition:

Dye # 1 0.130 g

Benzene 10 cra ^

Ethyl acetate 65 cm ^

10 ϊ aqueous gelatin solution 200 cm ^

5 Jt aqueous solution of an aluminum

kylnaphthalene sodium sulfonates 75 e * ¹¹

After drying, the dispersion became the second emulsion portion added in the molten state so that there was 0.132 g of dye for 1 mole of silver halide.

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Since »eel« · * EaulsieMpertleiMO, a · Dispersion of a purple red · !! Dye forming Coupler v «« tyrssolontyp In «In ·· high-boiling solids • oil sugegesen. Then 41 · emulsions were applied suitable trifvr on «trac» n ·

Dl · «rhalt ·» ·!) Plla · then became 1/25 second long alttala • la «r 500 Vatt Holfraalaap · In · 1η · η Int« naltitaskal «na« n-> • ltoavttr duroll «In Wr» tt «nfllt # r Mr. 15 exposed. Dl

Volfraala «p · was divided into 2f50 ° K» lnf ··. After exposure, the plate was developed as described in Example 1. The following results were obtained!

Senal warning Development time ReI .Es) -
pfind-
lithJceit Minlau «
density OElIXg e 12 minutes 100 0.65 • d 12 · 100 0.18 «C 14 ■ · 110 0.84 • d 14th · 110 0.24 • s 1 € " 126 1.06 • d 16 ■ 132 0.39

From the obtained results that when applying the method of the invention, a lower fog and a t increased relative sensitivity is achieved arises.

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leiaflel $

s «eltlTeapfladUe» e 0elatlne-311 »er * Alere» realdeaulaiea vwtu »ane state * a« in lab 11 ·· Sabvefelatea having Yerbindaag digested on eptiaale Bapflndllehkelt * Aneealleaead «rar« · 41 · Emulsion in i «« l -MB split · Belee Fertienen was "then tpektrmi Im Berelth Ten" 000 kl · 7000 A sen "lbllle ι

Bewlalen e) t

Al · Fareeteff became a ■ hlaiolyllden-a-Butenjrllden ^ -tÄlo-Afdenteln «llere«] reja «far» stoff, de »in the USA-fetentsehrift 2 177 403 eeaehrieeenesi type »used. 9 Parostoff was long »·») water krlPtlge «XOnren» u »an Aeeten-Meth» nol «- leeirne der la «! ·!« · sngeeetit. On 1 Hol SlleeraeJLegenid absent «0.040 § Pereetoff.

bMlslen f):

Under Yerwandwng de »glelenec rmrvetoffe» II a Oieperelen made of the following composition:

Farbateff Kr. 2 0.066 g

Bemol 25 en ³

Xthylaeetat awK 75 c » ³

10! "Ige aqueous" gelatin solution 200 g

5 S aqueous solution of alkyl,

naphthalene sodium sulfonate 100 on ^J.

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The swollen dye dispersion obtained was added to the light-sensitive, photographic emulsion in such an amount that 0.060 g of dye was used per mole of silver halide.

The two emulsion portions were then also with a Dispersion of a pheatlischen, a blue-green image-forming coupler in a high-boiling solvent. The emulsions were then applied to film supports.

The resulting films were then exposed for 1 second to a 500 watt tungsten lamp in an intensity scale sensitometer using a No. 29 Wratten filter. The tungsten lamp was set to 320 ° K. After exposure, the two films were developed as described in Example 1. The following results were obtained:

Sensitization Relative Em- Minimum Density

dutifully

according to e 100 0.06

according to f 1JJ2 0.06

From the results obtained, a considerable increase in the relative sensitivity of the emulsion sensitized according to the invention compared to that in known way sensitized emulsion.

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BAD ORlOiNAL Example 4

This example shows that an anti-fogging effect also occurs in the context of reverse development of photographic materials if these are developed, for example, according to a method as described in US Pat. No. 2,294,898, column 11 "Color Process 1". A significant anti-fogging effect occurs at slightly higher concentrations of the dye on and does Especially in the black and white development stage in the form of lower ^D _m i _n "" ^w erte and in full color reversal process in the form of higher _^Dmax ~ ^values noticeable.

The following table summarizes the results obtained with films made as described in Example 2, with the exception, however, that slightly higher dye concentrations were used.

Sensitive O, Black and white Relative Em
sensitivity Max 60 Color inversion tion ⁶ " 0, in 100 U 86 sensitivity C * 26th 100 1. 100 15th 100

In a ratio of 0.198 g dye / mol Ag.

Example 5 below describes a particularly advantageous method of dispersing spectral sensitizing dyes in a hydrophilic colloid. 909851/14 79

In this process, the dye is initially in one high-boiling solvent that is partially miscible with water. The dye is advantageously used in dissolved in a heated solvent in order to achieve the highest possible dye concentrations. The concentrated Dye solution is then dispersed in an aqueous, hydrophilic colloid, whereupon the mixture is preferably ground or homogenized. This creates an oil-in-water emulsion with small spheres of solvent that form the Contain dye. These dispersions can then be used for sensitizing photosensitive materials. Optionally, the dispersion can be allowed to cool and stored before going to sensitization photographic materials is used.

Example 5

A thiazyanine dye of the type disclosed in U.S. Patent 2,231 658 described type (dye A) and an oxacarbocy * - ^ nin dye of the described in US Pat. No. 2,295,276

of the same type (dye B) were dissolved in methanol and in a \ high-boiling solvent, namely phenoxyethanol. \

The following table summarizes the amounts of solvent which are required when using the known conventional method and the amounts of solvent which are required when using the method of the invention. 909851 / U79

A. Color Well-known ver
travel Procedure of
invention dye B. Color 1.5 g 1.5 g dye for 0.9 g 0.9 g Methanol
fabric A for 887.0 ml Methanol
fabric B 1065.0 ml

Phenoxyethanol for Dye A - 75.0 ml Phenoxyethanol for Dye B - 15.0 ml Total solvent 1952.0 ml 120.0 ml

Note that dye A is dissolved in methanol In in an amount of 0.05 g per 28.35 g of methanol and the dye B in an amount of 0.025 g per 28.35 g of methanol solves.

The phenoxyethanol was eifee to 104 ° C to the solution of Färbst A and ⁰ to 82 * C for solution of the dye B is heated.

When using the known method, 1952 ml organic solvent is introduced into the emulsion, while using the method of the invention at the same dye concentrations only 120 ml of organic solvents are introduced into the emulsion.

Advantageously, the solution of the dye in the high-boiling solvent in the hot state

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an aqueous colloid solution, for example an aqueous gelatin solution, the latter preferably containing a surface-active compound, followed by the whole is ground or homogenized. The dispersion obtained is then left to cool and can e.g. be stored at temperatures of 4 to 10 ° C. The gel obtained can are then mixed directly with a warm silver halide emulsion, whereupon dye particles precipitate and a crystalline one Form ne or amorphous, solid dispersion of fine particles of uniform particle size. The resulting dye dispersion has a large surface area, i.e., a high surface area to mass ratio, which accelerates dye dissolution and transfer to the silver halide grains.

Particularly good results are also obtained if, for example, n-butanol or instead of phenoxyethanol Ethyl acetate is used.

Will become apparent from the following Examples 6 and 7, the ER _x targetable lower fog values and higher sensitivities of emulsions has been sensibllislert with a dispersion of the game in examples V type described. 5

CO CD CO OO

cn example 6

C- Two multilayer color films of the In Example 1 cc of the USA patent 2,956,879.

represents. The green-sensitive emulsion was spectrally with an oxazole-thiohydantoin color of the in Example 3 the type described in US Pat. No. 2,282,116, 180 mg of dye were used per mole of silver halide.

In one case, the dye was made from a solution consisting of 25 mg of dye per 30 ml of acetone-methyl alcohol added in a ratio of 1: 1. In the second case, the dye was predispersed in gelatin, with 2 g Dye was used per 0.13 kg of dispersion. the The dispersion was prepared as described in Example 5. The cooled dispersion became the warm, light-sensitive emulsion added.

The films were imagewise exposed t and 25 minutes developed in a developer of the type described in Example 1 JTder US Patent 2,956,879. The following results were obtained:

green 8en3ibilislert with purple-red haze dye solution 0.22

Dye dispersion 0.11

The following example illustrates the increase in sensitivity, which arise when using the sensitization \ Can achieve the method of the invention.

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Example 7

Two multilayer color photographic materials with color developing agents were used as in Example 1 of FIG U.S. Patent 3,146,102.

The red sensitive emulsion was spectrally with a thiocarbocyanine dye of that in Example 9 of the United States patent 2 503 776 type described spectrally sensitized. Included 140 mg of dye was used per mole of silver halide.

In one case, the dye was added to the emulsion from a solution consisting of 120 mg of dye per 30 cm ^ of methyl alcohol. In the second case, the dye was added added to the emulsion in the form of a dispersion containing 2 g of dye per 0.454 kg of dispersion. The dispersion was produced as described in Example 5. The cooled dispersion was then added to the warm, photosensitive emulsion.

The films obtained were then exposed and developed as described in US Pat. No. 3,146,102, using an activator corresponding to Activator IVQ of the US Pat. The following results were obtained:

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red sensitized with relative sensitivity of the.-_ --- _-_-_ · __________ «_. red sensitive 11 emulsion layer

Dye solution 100 Dye Dispersion 151

Results corresponding to those described in Examples 6 and 7 were obtained when n-butanol was used as the solvent and if polyvinyl alcohol was used as the hydrophilic colloid instead of iQelatine.

The following example describes the preparation of a dye dispersion using a volatile, water-miscible solvent, whereby a dye solution is first prepared and the solution is then added to a heated aqueous solution of a hydrophilic colloid, which is then quenched and allowed to cool. The solvent is then evaporated, leaving a fine dispersion of dye crystals in the colloid. The dispersion can then be used for the spectral sensitization of photographic material. A grinding or a special homogenization of the obtained Dispersion is not required

Example 8

1.6 g of a 2.2 * cyanine dye were dissolved in 119 S methanol boiled under reflux conditions * after dissolving the dye * substance, the solution obtained was immediately in 909851/14 7 9

510 g of a 5 ί lgen aqueous gelatin solution at 35 ° C. are added. During the addition of the dye solution, the mixture was stirred vigorously. The dispersion obtained was immediately followed cooled and allowed to solidify. The dispersion was then added to a gelatin-silver halide emulsion.

The method of the invention is particularly suitable for the use of spectrally sensitizing dyes which are insoluble or practically insoluble in aqueous solutions. The process of the invention is particularly suitable for the use of those spectral sensitizing dyes whose solubility in water at 20 ^° C. is not greater than about 1 % .

Spectral sensitizing dyes processable by the process of the invention are particularly those the cyanine series, hemicyanine series or merocyanine series, Styryl series and the like, such as:

3,3 ^f -diethyIthiacarbocyaniniodid;

l ', 3-diethyl-7-methylthla-2 ^l -cyanine iodide; 2, £ -dimethylaminostyrylbenzothiazole ethiodide;

[2- (3-EthylthiazolineQ [] 1- (2-acetaminophen-5 (4) -thiazolonjdimethinemerocyanin;

Further also useful oxonol dyes, such as 3-hydroxy-3 ^t are, for example oxy-2,2'-methenyldithionaphthen or Phthaleinreihe, such as erythrosine. 9 0 9 8 5 1/14/9 BAD ORIGINAL

Others processable by the method of the invention Dyes are, for example, the dyes with an auxochromic amidelumion system, such as, for example, rhodanines, Pinacyanol dyes and pinaflavol dyes.

Dyes useful in the process of the invention are also disclosed, for example, in U.S. patents

1,846,301; 1,846,302; 1,942,854; 1,990,507; 2 112 140;

2,165,338; 2,493,747; 2,739,964; 2,493,748; 2,503,776; 2,519,001; 2,666,761; 2 734 900 and 2 739 149 as well as in British Patent 450,958.

Photographic materials which can be spectrally sensitized * by the method of the invention are in particular silver halides, such as SH-berbromide, silver chloride, silver iodide and mixed silver halides, such as Silberchlorojodld and Silver bromoiodide.

Other photographic materials which can be spectrally sensitized by the method of the invention, are for example T10_ and ZnO.

The photographic material to be sensitized by the process of the invention can be dispersed or suspended form in a hydrophilic colloid binder

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demittellösung present »The method of the invention can however, they can also be used for the spectral sensitization of binder-free • precipitates of photographic materials, such as, for example, for sensitizing light-sensitive silver halide layers, which are deposited in a vacuum can be produced from silver halide on a support.

The most varied of substances can be used for the preparation of the dye dispersions Solvents can be used. Cyanine dyes are generally in lower alcohols such as Methanol and merocyanine dyes in general Easily soluble in ketones such as acetone. The used Organic solvents can be miscible with water, immiscible with water or partially in water be soluble.

In an advantageous embodiment of the method of the invention, the solvent has such a high vapor pressure that it can easily volatilize from the hydrophilic colloid, so that dispersions easily remain, which are completely solvent-free. On the other hand it is The amount of solvent remaining in the dispersion is so small that there are no difficulties in applying the emulsions af photographic carriers occur.

The use of with has proven to be particularly advantageous

Water partially miscible solvents proved the 909851/14/9

have a water solubility of from about 1 to 8% at room temperature (20 ⁰ C) and boiling points above 80 ° C. Such solvents include, for example:

Pentanol-2, ethyl acetate,

n-butanol, methyl-n-propyl ketone,

2-methylpropanol-1, methyl isobutyl ketone,

Butyl carbitol acetate, methylphenyl carbitol,

Cyclohexanol, 2-ethyl-l, 3-hexanediol unü

Cyclohexanone, diethyl acetal.

It has been shown that when using such solvents, particularly fine dispersions, i.e. dispersions with particularly small particle size can be obtained. The use of old solvents with boiling points above 80 ° C has proven to be particularly advantageous because it is particularly concentrated when such solvents are used te solutions can be made and the dyes are usually more soluble at elevated temperatures.

It has been shown that in order to achieve particularly advantageous spectral sensitivities, the particle size of the dye crystals The hydrophilic colloid should advantageously be less than about 1 micron »

The method of the invention is particularly suitable for spectral sensitization of hydrophilic, photographic emulsions, which are deposited on supports at high speeds

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be carried, for example at speeds of above 46 m per minute.

It has often proven useful to use the dye dispersions warm photographic emulsions just before they are applied to a support.

According to the invention, the dye dispersions can be concentrated, added to photographic systems, especially concentrated photographic silver halide emulsions e.g. gelatin silver halide emulsions of which more than 1/20, e.g. 1/3 or more of a silver halide and the viscosities of at least 50 cps, for example 500 cps or more.

The method of the invention can be particularly advantageous

use in the context of coating processes in which several layers are applied in one operation, whereby the application of the second and the following layers takes place before the previous layer has dried or

in which the casting of the layers by methods with high

Speeds takes place,

as for example in the UK patents 855 216 and 925 179 and U.S. Patents 2,620,285 and 2,681,294.

The emulsions sensitized by the process of the invention can optionally simultaneously with at least el- 9 0 9 8 5 1 / U 7 9;

- 21 -

Another coating composition on a photographic one Carriers can be applied as described, for example, in U.S. Patents 2,911,898 and 2,761,791 will. Appropriately, emulsions with a viscosity of 50 to 150 cp are used and coating speeds of about 45 to 152 m per minute are maintained.

It has been found that the dispersions used according to the invention for sensitization are extremely stable are. In contrast, it is known that solutions of spectrally sensitive dyes in organic solvents are only stable for a very short tent.

A wide variety of hydrophilic, water-permeable, organic colloids are suitable for producing the dispersions used according to the invention. Gelatin is preferably used. However, colloidal substances such as colloidal albumin, cellulose derivatives, synthetic resins and the like are also particularly suitable. For example, polyvinyl alcohol or hydrolyzed polyvinyl acetates, as described, for example, in US Pat. No. 2,286,215, and hydrolyzed cellulose esters, such as cellulose acetates up to hydrolyzed to an acetyl group content of 19 to 26% , as described for example in US Pat. No. 2,327,808,

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water-soluble ethanol arain cellulose acetates, as described, for example, in US Pat. No. 2,322,085, polyacrylamides with a combined acrylamide group content of 30 to 60 % and a specific viscosity of 0.25 to 1.5 or imldislerte polyacrylamides with the same acrylamide group content and corresponding viscosities, such as, for example , described described in US Patent No. 2 5 ¹ Il 47Ί zein as described for example in US Patent 2,563,791 Vlnylakoholpolymere with Urethancarbonsäuregruppen, such as in US Patent 2,768 15I, cyano-acetyl groups-containing polymers, such as Vinyl alcohol-vinyl cyanoacetate copolymers, as described, for example, in US Pat. No. 2,808,331, or polymeric products obtained by polymerizing a protein or a saturated acylated protein with a monomer with vinyl groups, such as, for example, in US Pat. No. 2,852,382 damn rubbed.

Another advantage of the method is based on the invention finally, that the risk of explosion or the risk of ignition by using lesser Amounts of organic solvents is reduced.

Furthermore, it was ultimately not to be expected that, when the process of the invention was carried out, the sensitizing dye would be replaced by an aqueous solution of a hydrophilic one 909851/1479

Colloid in which the dye is relatively insoluble, would diffuse and of light-sensitive compounds, how, for example, silver halide crystals would be absorbed »

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Claims (1)

Claims 1.) Process for the spectral sensitization of light-sensitive, photographic materials, particularly photographic silver halide emulsions, by means of spectral means Sensitizing sensitizing dyes, characterized in that the photographic to be sensitized Material with a dispersion of a spectrally sensitive dye in a hydrophilic colloid brings in contact. 2. The method according to claim 1, characterized in that one. the dispersion of the spectral sensitizing dye of a dispersion of light-sensitive material in one Colloid adds 3. The method according to claims 1 and 2, characterized in that that a dye dispersion prepared by dissolving a dye which is insoluble or practically insoluble in water substance in an organic solvent and dispersing the solution in a hydrophilic colloid. k, process according to Claims 3, characterized in that a dispersion of a spectral sensitizing dye in gelatin is used. 90 9851 / U9 5. The method according to claims 1 to 4, characterized in that a dye (dispersion prepared by dissolving a water-insoluble or practically insoluble dye in an organic solvent having a boiling point of over 80 ⁰ C and a solubility in water at 20 ° C from 1 to 8 i and dispersing a hot, concentrated solution of the dye in a hydrophilic colloid, used 6. The method according to claims 1 to 5, characterized ₉ that a dye dispersion prepared by dissolving a dye in a solvent at above 80 ° C, dispersing the solution in an aqueous gelatin solution containing a surface-active compound, Veraahlsen the dispersion up to one Dye particle size of less than 1 micron diameter and cooling the dispersion used and that the dispersion of a liquid gelatin-silver halide emulsion. * Us * et, ast. 7. The method according to claims 3 to 6, characterized in that that nan uses phenoxyethanol as an organic solvent. 8. Jerfahren according to claims 1 to 7, characterized in that that a thiacyanine, cyanine, nin, styryl or oxanol dye used. ^; ' 9. Process according to Claims 1 to 8, characterized in that a dye dispersion prepared by Dissolving a dye in a water-miscible solvent, dispersing the solution in a hydrophilic one Colloid and evaporation of the solvent, used BATH ORIGINAL 909851/1479