DE3250123C2 - Photographic recording material - Google Patents

Abstract

The invention relates to a multicolor photographic recording material having a support and emulsion layers thereon for the separate recording of blue, green and red light, each with silver halide grains dispersed in a dispersion medium having an average diameter of not more than 10 microns, and green and red spectral sensitizing Dyes in the green or red light recording layers. At least one of the green and red light-recording emulsion layers contains chemically and spectrally sensitized silver bromide or silver bromoiodide tabular grains having a thickness of less than 0.3 microns and an average thickness of at least 0.03 microns, a diameter of at least 0.6 microns, and have an average aspect ratio of 8: 1 to 100: 1. They account for at least 50% of the total projected area of the grains of the layer.

Description

Usually, the sensitivity of the silver halide emulsions becomes beyond its natural spectral sensitivity range only slightly enhanced by chemical sensitization. The sensation The nature of photographic silver halide emulsions can be determined but over the entire visible spectrum and beyond by using spectral sensitizers, in typically extend by use of methine dyes. The emulsion sensitivity over the range of natural sensation In addition, the level of use increases spectral sensitizer to an optimum value and then generally decreases rapidly, such as for example is known from the book of Mees, "Theory of the Photographic Process ", published by Macmillan, 1942, pages 1067-1069.

Within the range of silver halide grain sizes, the more normal wise for the production of photographic recording materials used, the maximum sensitivity increases optimal sensitization is achieved, linear with increasing Grain size too. The number of absorbed quanta required is to make a grain developable, is from the grain size is practically independent, but the density is a given Number of grains generated in the development, directly from their Size dependent. For example, if you want a maximum density of 2 are achieved, so are to achieve this density less Grains of a mean diameter of 0.4 microns required as a mean diameter of 0.2 microns. Less radiation is needed to make less grains developable.

Regrettably, since the ones produced by the larger grains occur Density is concentrated in fewer places, larger grains greater density variations. Such density fluctuations, the  to offer themselves to the viewer are called "graininess". The most common is to apply the graininess as "RMS granularity" which is defined as the density standard deviation within a micro-aperture (eg 24-28 microns).

Is the maximum possible granularity for an emulsion layer, often also referred to as "grain" identified, so too the maximum sensitivity in the case of this emulsion layer can be achieved, effectively set.

In the past years are in the field of photography intensive research to achieve maximum photographic Sensitivities have been carried out in the absolute sense. These Research, however, aimed at achieving maximum sensation with optimal sensitization and satisfactory Granularity or grain criteria. Real improvements allow the sensitivity of silver halide emulsions increasing the sensitivity without increasing the graininess, the reduction of graininess without loss of sensitivity or the simultaneous improvement of both the sensitivity as well as the graininess. Such sensitivity improvement is often referred to in the literature as an improvement of the Sensitivity-granularity ratio of an emulsion be records.

In the diagram of FIG. 1 are for five different silver halide emulsions 1, 2, 3, 4 and 5 of the same composition, but different grain size, the same sensitized bili in the same way applied to support and developed in the same way, the sensitivities applied as a function of graininess. Although the individual emulsions differ in their maximum sensitivity and granularity, there is a predictable linear relationship between the emulsions as indicated by the sensitivity Grain Line A. All emulsions lying on the straight line A have the same sensitivity-granularity relationship. Emulsions characterized by a true speed enhancement lie above the speed granularity straight line A. For example, the emulsions 6 and 7, which are on the common sensitivity granularity straight line B, are each of the sensitivity-granularity ratios Emulsions 1 to 5 superior. The emulsion 6 has a higher sensitivity than the emulsion 1, but no higher granularity. The emulsion 6 has the same sensitivity as the emulsion 2, but a considerably lower granularity. The emulsion 7 in turn has a higher sensitivity than the emulsion 2, but a lower granularity than the emulsion 3, which in turn has a lower sensitivity than the emulsion 7. The emulsion 8, which is below the sensitivity-granularity straight line A, has the worst sensitivity-granularity ratio of the Emul ions shown in Fig. 1. Although emulsion 8 has the highest photographic sensitivity of the emulsions, this sensitivity has only been achieved by a disproportionate increase in granularity. The importance of the sensitivity-granularity relationship has led to a strong effort to quantify and generalize sensitivity-granularity determinations. Normally, it is a straightforward process to accurately compare the sensitivity-granularity ratios of the emulsions of an emulsion series, which differ in one feature, for example, the silver halide grain size. Often the sensitivity-granularity ratios of photographic products are compared which provide the same or similar characteristic curves. However, universal quantitative sensitivity-granularity comparisons of photographic recording materials have not been achieved to date because sensitivity-granularity comparisons are increasingly subject to subjective judgment as other photographic features diverge. Finally, comparisons of photosensitivity ratios of photographic materials providing silver images (e.g., black-and-white photographic materials) to recording materials used to form color images (e.g., color recording materials and chromogenic recording materials) are numerous to consider other considerations than the silver halide grain sensitivities, since the nature and origin of the substances which produce the density and consequently contribute to granularity are very different. For granularity measurements in the case of silver and color images, reference is made, for example, to Kodak Publication No. F-20 entitled "Understanding Graininess and Granularity" (available from Eastman Kodak Company, Rochester, New York 14650); The work of Zwick "Quantitative Studies of Factors Affecting Granularity" published in the "Photographic Science and Engineering" reference, Vol. 9, No. 3, May-June 1965; the work of Ericson and Marchant: "RMS Granularity of Monodisperse Photographic Emulsions", published in the reference "Photographic Science and Engineering, Vol. 16, No. 4, July-August 1972, pages 253-257 and the work of Trabka:" A Random-Sphere Model for Dye Clouds ", published in the journal" Photographic Science and Engineering, Vol. 21, No. 4, July-August 1977, pages 183-192.

It is further known that other than silver bromide iodide emulsions for the production of photographic recording materials of Camera sensitivity find only limited use. A Silver bromide iodide emulsion with particularly advantageous sensibility ness-granularity ratios for the production of Silver images (black and white) are known from US Pat. No. 3,320,069. In particular, gelatine silver bromide is disclosed in this patent iodide emulsions having an iodide content of 1 to 10 mol% described.  

The emulsions are sensitized with a sulfur, selenium or tellurium sensitizer. Such an emulsion has, after application to a support in a Beschich thickness of 300 to 1000 mg per 0.929 m ² and exposure in a sensitometer with an intensity scale and 5 minutes of development in a developer of angege surrounded composition at 20 ° C:

Water (50 ° C) 500 ml Methyl-p-aminophenol 2.5 g Sodium sulfite, dehydrated 30.0 g hydroquinone 2.5 g alkali 10.0 g potassium 0.5 g AL = L <Made up to 1 liter with water

a logarithmic sensitivity of 280 to 400 and a residual value (obtained by subtracting the granularity value from the logarithmic sensitivity value) of 180 to 220.

To prepare such emulsions, gold is preferably used in combination with a sulfur group sensitizer. Furthermore, thiocyanate may be present during silver halide precipitation or may be added at some point prior to watering the emulsion. The use of thiocyanate during silver halide precipitation and sensitization is further known, for example, from US Pat. Nos. 2,221,805, 2,222,264 and 2,642,361. The emulsions known from US Pat. No. 3,320,069 are further characterized by excellent speed-granularity ratios in the case of color photographic recording materials, although quantitative values for color image granularity are not reported. In only a few cases have the highest achievable photographic sensitivities been studied at levels greater than those normally used. Farnell, in a paper entitled "The Relationship Between Speed and Grain Size," published in The Journal of Photographic Science, vol. 17, 1969, pages 116-125, reports on blue sensitivity studies on silver bromide and silver bromoiodide emulsions without spectral sensitization He found that with grain sizes greater than about 0.5 microns ^2, with projected area (diameter of 0.8 microns), no further increase in sensitivity can be achieved with increasing grain size, which is not surprising, assuming The number of absorbed light quanta required for developability is independent of the grain size, and a decrease in sensitivity with increasing grain size is reported by the author. The author attributes the decrease in sensitivity of large grains to their size relative to the limited one middle diffusion distance from photo generated electrons, which are needed for the production of latent image centers back. Thus, more quantum of light must be absorbed by a large grain than by a small grain to produce a developable latent image.

In another work entitled: "Factors Influencing Photographic Sensitivity ", published in the literature J. Soc. Photogr. Sci. Technol. Japan, Vol. 43, No. 6, 1980, Pages 335-346, the author agrees with Farnell and stretches the discussion of diminished sensitivity of large silver halide grains for additional reasons based on the back in a spectral sensitizing dye are to be supplied. In the work cited, the author reports that the sensitivity of spectrally sensitized emulsions In addition, the relative quantum yield is additionally influenced by (1) spectral sensitization, (2) dye desensitization and (3) light absorption by dyes. The author states that the relative quantum efficiency of the spectral sensitization  practically theoretical and as a result practically not is to be improved. The author further states that the light absorption by grains, that of dye molecules are covered, is proportional to the grain volume, if the grains blue light are exposed and the grain surface when the Grains minus blue light are exposed. This means that the Size of increase of minus blue sensitivity in general is less than the increase in blue sensitivity when the Size of the emulsion grains is increased. Attempts to increase the Lead to light absorption by increasing the coverage of the dye not necessarily to increased sensitivity since the dye desensitization with the amount of added Dye rises. The desensitization is rather on a diminished latent image production as a diminished one Attributed to photogeneration of electrons. Tani beats Ver improvements in the sensitivity-granularity ratio of larger silver halide grains by producing core-shell Emulsions to prevent desensitization before. A internal doping of silver halide grains with the goal of Ver use of otherwise desensitizing concentrations Dyestuffs are also known from US Pat. No. 3,979,213.  

It is further known that silver bromide and silver bromide iodide emulsions have sufficient natural sensitivity against the blue region of the spectrum to blue To be able to record radiation without a spectral blue sensitization. If such emulsions to on Drawing of green and / or red (minus blue) light used, so they are spectrally sensitized accordingly. In case of Black and white photography and the monochrome (eg chromogenic) Photograph is the obtained orthochromatic or pan chromatic sensitivity advantageous.  

In the case of multicolor photography is the natural sensation of silver bromide and silver bromide in emulsions, which are used for recording blue light, advantageous. However, when these silver halides are processed in emulsion layers turning to the recording of the green or red area of the Spectrum used, so is the natural blue sensation annoying, since a response for both blue and green light or both blue and red light in the emulsion layers the color tone of the multi-color image that will be recorded should, falsified.

In the case of multicolor recording materials under Use of silver bromide or silver bromoiodide emulsions have been prepared, can the color distortion of two consider separate points of view. The first point of view is the difference between the blue sensitivity of the green or red-recording emulsion layer and its green or red sensitivity. The second point of view is the difference between the blue sensitivity of each blue recording Emulsion layer and the blue sensitivity of the corresponding green or red recording emulsion layers. Generally it is in the production of multicolor photographic Recording materials used to record accurate image colors under daylight conditions (eg 5500 ° K), the goal, a difference of about an order of magnitude between the blue sensitivity of each blue light recording Emulsion layer and the blue sensitivity of the corresponding green or red light-recording emulsion layers to reach. It has been shown that the targeted Sensitive Differences in the use of silver bromide or silver bromide iodide emulsions can not be achieved unless it One or more modifications occur to the color falsification to correct. But even then sensitivity can be differences of a full magnitude in the product are not always  realize. However, even if the targeted Sensitive differences are realized leads to a further increase the separation between blue and minus blue sensitivity to one further reduction of the record of blue light Layers intended for recording minus blue light are.

By far the most common attempt the exposure of red and green-sensitized silver bromide and silver bromide iodide emulsions layers with blue light to thereby reduce their blue Effectively reducing sensitivity is this Emulsion layers below a yellow (blue absorbing) To arrange filter layer. For this purpose, both yellow Use filter dyes such as yellow colloidal silver. In one usual multicolor recording material consist all the emulsion layers of silver bromide or silver bromide iodide emulsion layers. The emulsion layers, the green and red To record light are located below one yellow filter, whereas the emulsion layer or emulsions layers that are to record blue light, above the Filter layer are arranged.

However, this arrangement of the layers has a number of times divide. While the recording of blue light through the Green light and red light recording layers on one tolerable level is diminished by the use a yellow filter layer a less than ideal layers arrangement. So meets the green light and red Light-recording emulsion layers light up that already the blue emulsion layer or the blue emulsion layers and the yellow filter layer has passed. In the process, the light becomes scattered, reducing the sharpness can be reduced. Because the blue light recording emulsions the least with respect to the visible record important layer carries its preferred position next to  Light source not to the sharpness to the extent at, such as by an appropriate arrangement of red light or green Light-recording emulsion layers. Furthermore, the yellow filter layer itself imperfect and absorbed to a lesser extent light of the green part of the spectrum, what leads to a loss of green sensitivity. Come in addition, that the yellow filter material, especially when it is out yellow, colloidal silver, which increases material costs and This leads to the development of the recording material used developing solutions, such as bleaching and Bleach-fix solutions will soon be replaced with new solutions have to.

Another disadvantage of the separation of blue emulsions layer or blue emulsion layers of a recording material from the red and green emulsion layers by insertion of a yellow filter layer occurs, is that the sensitive speed of the blue emulsion layer is reduced. This effect occurs because the yellow filter layer is blue light absorbed by the blue emulsion layer or layers otherwise, with the reinforcement of the exposure again could be reflected. In GB-PS 1 560 963 it is proposed to increase the sensitivity by the fact that the yellow filter layer is shifted so that they are not immediately below the blue emulsion layer is located. From GB-PS 1 560 963 results However, that the increase in the blue sensitivity only is achieved at the expense of adverse color reproduction in the green and red sensitized emulsion layers below the yellow filter layer.

There are further known proposals, the yellow To eliminate filter layers. However, it has been shown that Each of these proposals is subject to disadvantages. That's the way it is from US-PS 2,344,084, for example, a spectral green or red sensitized silver chloride or silver chloro  bromide emulsion layer to be arranged so that this layer of the closest to the light source used for exposure, since these silver halides are negligible or low have natural blue sensitivity. Because silver bromide one it does not produce high natural blue sensitivity the closest to the light source layer, but forms the emulsion layer used to record blue light is determined and lies down.

It is further known from US Pat. Nos. 2,388,859 and 2,456,954. a pollution of the green light and red light recording To avoid emulsion layers by blue light in that these layers are made 50 or 10 × less sensitive as the blue light-recording emulsion layer. The emulsions layers are covered with a yellow filter layer to a sensitivity adjustment of the blue, green and red light recording emulsion layers against blue, green or red light and to separate blue and minus Blue sensitivities of the minus-blue recording emulsion to increase levels.

This measure allows the emulsion layers in each desired layer arrangement to be applied to a support. A disadvantage of the known material, however, is that a yellow Filter layer is used, not to mention further after divide. To the sensitivity differences in the blue light and minus blue light recording emulsion layers without need to achieve the use of a yellow filter layer according to the teachings of U.S. Patents 2,388,859 and 2,456,954 larger silver bromide or silver bromoiodide grains in the blue light recording emulsion layer can be used. Attempts to achieve the desired sensitivity differences due to differences in grain size alone resulted in the blue light-recording emulsion layers are very grainy and / or that the grain size of the minus blue light-recording emulsion layers is extremely low,  why these layers have a low sensitivity. To remedy this difficulty, it is still known that Proportion of iodide on the grains of blue light recording To increase emulsion layer, thereby the blue sensitivity to increase the layer without increasing the grain size. Should the minus blue light recording emulsion layers more than have only a very moderate photographic sensitivity, so it is not possible blue-recording emulsion layers at least 10x greater sensitivity within normal Wise to achieve acceptable grain sizes, and not with an increased iodide content in the blue light recording Emulsion layer.

Although yellow filter layers are used to form the Impact of blue light on under the yellow filter layer They can, however, reduce their lying emulsion layers Do not eliminate the passage of blue light. This means, even if yellow filter layers are used, additional Advantages of further separation of blue and minus blue sensitivities of silver bromide and silver bromide iodide emulsions which can be achieved in the Record minus blue area of the spectrum.

Although silver chloride and silver chlorobromide emulsions are described in photo graphical multi-color recording materials for use with Use minus blue record layers without yellow filter protection as proposed in US Pat. No. 2,344,084, It should be noted that these emulsion layers also blue Absorb radiation, albeit of lesser amount. There are Use cases in which even a slight absorption in the blue Range of Spectrum (often referred to as "tail absorption") be disadvantageous in these emulsions containing silver chloride can. For example, if a photographic recording material with a silver chloride emulsion layer on camera sensitivity of radiation outside the blue region of the spectrum (for example, the green, red  or infrared region) and should be the recording material can be developed in the presence of blue light, so can the Emulsion layers have a sufficient natural blue sensitivity to increase the background density or fog increase as a result of the exposure of the work surface. Although the blue sensitivity of the chloride containing emulsion layer only a small part of their sensitivity to that at the imagewise exposure used radiation is, is not it the duration of the exposure with that available during development Light much longer. As a result, even silver chloride and silver chlorobromide emulsions benefit from a reduction their sensitivity to blue in relation to their sensitivity over other spectral ranges.

It is also known that in photographic silver halide Emulsions produce a variety of regular and irregular grain shapes can occur. Regular silver halide grains are often cubic or octahedral. The grain edges may be due to Ripening effects have rounding and in the presence of strong Maturing agents, such as ammonia, may even grain assume a spherical shape or occur in the form of thick platelets, which are nearly spherical, as described, for example in U.S. Patent 3,894,871 and in the book by Zelikman and Levi "Making and Coating Photographic Emulsions", published by Focal Press, 1964, pages 221-223. It is also known that rod-shaped and tabular grains in various proportions in the mixture can occur with other grain shapes, especially if the pAg value, d. H. the negative logarithm of the silver ions concentration of the emulsion) was changed during the precipitation, which is the case, for example, with single-run precipitation.

Tabular silver bromide grains have been extensively studied. This is especially true for macro sizes that are not photographic To have availability.  

Among tabular grains here are grains with two parallel or practically parallel crystal surfaces, of which each one is much larger than the other single crystal surfaces of the grain, to understand. The aspect ratio, d. H. the ratio of diameter to thickness of the sheet-like Grains is much larger than 1: 1.

Silver bromide emulsions with tabular silver bromide grains with high aspect ratio are known, for example from the Ar by de Cugnac and Chateau "Evolution of the Morphology of Silver Bromide Crystals During Physical Ripping ", published in the journal "Science et Industries Photographiques", Vol. 33, No. 2 (1962), pages 121-125.

From the company Eastman Kodak Company is from 1937 to in the 50s a double coated radio graphic footage called "No-Screen X-Ray Code 5133 ", containing the material on the two opposite sides of the layer Carrier layers of sulfur-sensitized silver bromide emulsions. Since the emulsions are exposed by X-ray were radiant, they were not spectrally sensitized. The tabular silver halide grains had an average Lich aspect ratio at about 5 to 7: 1. The tabular Grains accounted for more than 50% of the projected area where against the non-tabular grains more than 25% of the projected Make up surface. In repeated reproduction attempts this Emulsions showed that the emulsion with the thinnest or lowest average grain thickness tabular grains with a average or average grain diameter of 2.5 micro meters and a mean or average grain thickness of 0.36 microns and that the mean or average Aspect ratio was 7: 1. In case of other attempts to Preparation of the emulsions contained the emulsions thicker panel shaped silver halide grains of smaller diameter with a lower average aspect ratio.  

Although silver bromide iodide tabular grain emulsions However, none of these emulsions has a high through average aspect ratio. A discussion of blackboard silver bromide iodide grains is found in the book of Duffin, "Photographic Emulsion Chemistry", published by Focal Press, 1966, pages 66-72 and in a work by Trivelli and Smith titled "The Effect of Silver Iodide Upon the Structure of Bromo-Iodide Precipitiation Series ", published in the period Writing "The Photographic Journal, Volume LXXX, July 1940, pages 285-288. The authors of the latter reference observed a marked decrease in both grain size as well as in the aspect ratio with introduction of iodide. In a Work by Gutoff entitled "Nucleation and Growth Rates During the Precipitation of Silver Halide Photographic Emulsions ", published in the journal "Photographic Sciences and Engi neering ", Vol. 14, No. 4, July-August 1970, pages 248-257 from the preparation of silver bromide and silver bromoiodide emulsions of the type prepared by single-run precipitation method Use of a continuous precipitation device, reported.

From DE-OS 27 25 993 is a process for the preparation of photographic emulsions containing silver halide crystals of Keep twin type, known. In particular, from the DE-OS 27 25 993 an improved process for the preparation of Twin-type emulsions of silver iodobromide, silver iodide chloride or silver iodochlorobromide by targeted Ein Construction of silver iodide in the silver halide crystals during known for their growth. The forth by the known method Asked emulsions are characterized by a reduced Dispersity and can be images of high contrast develop.  

More recently, methods for the production of Emulsions have become known in which a substantial proportion of the silver halide in the form of tabular grains. Thus, in US Pat. No. 4,063,951, silver halide crystals of a tabular habit bounded by cubic {100} faces are and an aspect ratio (relative to the edge length) of 1.5 to 7.1, described. The tabular grains point square and rectangular main surfaces that are characteristic for {100} crystal faces. From US-PS 4,067,739 is and a process for producing silver halide emulsions known in which most of the crystals of the octahedral twin type are. In the known method, seed crystals are first which is grown under magnification of an Ostwald ripening throws on what you think grain growth without Renukleierung or Ostwald- Maturation completed, under control of pBr, d. H. the negative logarithm of the bromide ion concentration. From the U.S. Patent Nos. 4,150,994, 4,184,877 and 4,184,878, and British Patent 1,570,581 and DE-OS 29 05 655 and 29 21 077 are also methods for Preparation of silver halide grains of a flat octahedral Gemini configuration by using seed crystals, the at least 90 mol% of iodide known.

From several of the last mentioned references it is known that the emulsions described in these references a have increased opacity and are suitable for the production of both Black and white as well as color recording materials of the camera type suitable. In US Pat. No. 4,063,951, the highest is indicated Aspect ratio at 7: 1, but results from the very low Aspect ratios given in the example and only 2: 1, that the stated aspect ratio of 7: 1 is unrealistically high. Also shows a rework of the example and show the photomicrographs of US Pat. No. 4,067,739  and the other aforementioned patents that the aspect ratios of the tabular silver halide grains of the well-known emulsions are well below 7: 1. Another method for Preparation of Tabular Sil Silver Halide Emulsions berhalogenidkörnern similar to that known from US-PS 4,150,994 However, this does not affect the use of silver iodide is restricted as seed crystals, is from the Japanese Patent Application Kokai 142 329 known.

The object of the invention is a multicolored photographic Recording material with a support and applied thereon Emulsion layers for the separate recording of blue, green and red light, each in a dispersion medium distributed silver halide grains with an average Diameter of not more than 10 microns and green and red spectral sensitizing dyes in the green or red Indicate light-recording layers, in which at least one the green and red light recording emulsion layers has improved sensitivity-granularity ratio and an increased minus blue sensitivity (green or red sensitive in relation to the natural blue sensitivity.

This task is solved with a multicolored photographi recording material as indicated in the claims is net.

The recording materials according to the invention have opposite comparable photographic recording materials of the State of the art has significant advantages. Will the Preparation of the recording materials used emulsions  spectrally outside the blue region of the spectrum, whereas they have a natural sensitivity sensitized, they show a strong separation of theirs Sensitivity in the blue region of the spectrum on the other hand they have a natural sensitivity to the area of the spectrum, on the other hand, they are spectrally sensitized. It was found that minus blue sensitized silver halo genid-, z. B. silver bromide and silver bromoiodide emulsions, for the preparation of inventive recording materials can be used much less sensitive to Blue lights are as opposed to minus blue light and no filter require protection to acceptable minus blue records when exposed to neutral light, for example, daylight of 5500 ° K.

The drawings serve to illustrate the invention. In detail are shown in:

Figures 1 and 3-6 are diagrams showing the dependence of sensitivity on the granularity of different emulsions;

FIG. 2 is a photomicrograph of a high aspect ratio tabular silver halide grain silver halide emulsion useful in the invention . FIG .

The term "high aspect ratio" used here means in that the silver halide grains have a thickness of less than 0.5 micrometers (in particularly advantageous embodiments less 0.3 microns) and a diameter of at least 0.6 Microns, an average or average aspect ratio greater than 8: 1 and at least 50% of the total projected area of the silver halide grains.

Especially advantageous is the use of such Silver halide emulsions proved their silver halide grains a thickness of less than 0.3 microns, optimally less than 0.2 microns, a diameter of at least 0.6 microns and an average or average aspect ratio of at least 12: 1, and optimally at least 20: 1 point. According to a further advantageous embodiment of the Invention accounts for at least 70% of the total projected area  the grains of tabular silver halide grains of the angege give thickness and diameter ratios. In the optimal case At least 90% of the total projected area of the grains come from the layer of tabular silver halide grains of give thickness and diameter ratios.

It should be noted that the thinner the tabular grains are, which contribute to a certain percentage of projected area the higher the average aspect ratio of the emulsion is.

Typically, the tabular silver halide grains have an average thickness of at least 0.03 microns, preferably at least 0.05 microns.

To him It is believed that the thickness of the tabular grains is increased can to meet special applications. For example can be especially in the case of recording materials for the image transmission method, e.g. B. in the case of Bildüber supporting units are sheet-shaped silver halide grains with medium or average thicknesses of up to 0.5 microns ver turn.

Grain thicknesses of up to 0.5 micrometers will also be discussed below discussed for the recording of blue light. To achieve of high aspect ratios without unusual increase in the Grain diameter is usually recommended that the blackboard shaped grains of the emulsions have an average thickness of less than 0.3 microns.

The grain characteristics of the silver used in the invention Halide emulsions can be known to the person skilled in the art Determine methods.  

As already stated, under the "aspect ratio" is the To understand the ratio of diameter to thickness of a grain. The "diameter" of a grain is in turn defined as the Diameter of a circle with an area that is the same projected area of the grain resulting from a photomicrograph or an electron beam micrograph of an emulsion sample is recognizable. From the shadow districts of electron beam Micrographs of emulsion samples allow the thickness and the Determine the diameter of each grain. Furthermore, can be identify such tabular grains having a thickness of less than 0.5 or 0.3 microns and a diameter of have at least 0.6 microns. From these values can be the Aspect ratio of each such tabular grain calculate the aspect ratio of all tabular Grains in the sample that have a thickness of less than 0.5 or 0.3 microns and a diameter of at least 0.6 micro meters can be averaged, from which the middle or average aspect ratio.

By this definition is the average aspect ratio the mean value of the individual aspect ratios of the individual Grains. In practice, it is usually easier, a medium or average thickness and a mean or average diameter of the tabular grains with a Thickness of less than 0.5 micrometers (0.3 microns) and a Diameter of at least 0.6 microns and the average Aspect ratio as the ratio of these two means to reach. Regardless of whether the average individual aspect ratios or the averages of thicknesses and diameters used be used to determine the average aspect ratio, within the tolerances of the grain measurements, the obtained average aspect ratios are not significantly different from.  

The projected areas of the tabular silver halide grains, which satisfy the thickness and diameter criteria can be summed up. Furthermore, the projected areas of the remaining silver halide grains in the photomicrograph be summed separately. From the two determined sums leaves then the percentage of the total projected area of the Tabular silver halide grains having the indicated silver halide grains Calculate thickness and diameter criteria.

For the given determinations, a reference grain thickness for a tabular grain of less than 0.5 microns, (preferably wise 0.3 microns) given to the very thin board shaped grains of thicker tabular grains, with bad to distinguish photographic properties. A reference grain diameter of 0.6 microns was selected as it was at smaller diameters is not always possible in micrographs to distinguish tabular grains from non-tabular grains. The term "projected area" is used here in the same sense needs like the terms "projection surface" and "projective Surface ", which are often used side by side in the literature. Reference is made, for example, to the book by James and Higgins Fundamentals of Photographic Theory, published by Morgan and Morgan, New York 1948, p. 15.

FIG. 2 is an example of a photomicrograph of an emulsion used in accordance with the present invention selected to illustrate the various types of grains which may be present. FIG. In the case of the grain 101 , it is a tabular grain satisfying the specified thickness and diameter criteria. Photomicrography shows that the vast majority of the grains of Figure 2 are tabular grains that satisfy the thickness and diameter criteria given. The grains had a mean aspect ratio of 18: 1. As can be seen from the photomicrograph, there are also a few grains that do not satisfy the given thickness and diameter criteria. The grain 103 z. B. is a non-tabular grain. It has a thickness of over 0.3 microns. The grain 105 example, is a fine grain that does not meet the diameter criteria. Finally, the grain 107 is a thick tabular grain which satisfies the required diameter criterion but does not satisfy the thickness criterion.

Depending on the conditions under which the emulsion is produced takes place, in addition to the desired tabular Silver halide grains having the indicated thicknesses and diameters knife criteria, secondary grain populations of larger ones non-tabular grains, finer grains and thicker slab produce shaped grains. Possibly. may be other non-tabular Grains, such as rods or needles may be present. Although It has proven to be advantageous in general, the number of tabular grains corresponding to the indicated thicknesses and diameters knife criteria suffice to maximize the presence of secondary grain populations may be appropriate in some cases, provided that the emulsions have the stated high aspect maintain a relationship.

According to a particularly advantageous embodiment of the invention the recording material according to the invention has at least one Silver bromide iodide emulsion layer containing tabular silver bromide iodide grains of the specified high aspect ratio.

Silver bromide photographic silver iodide tabular emulsions He has high aspect ratio silver bromide iodide grains according to the invention for the production of photographic recording materials can be used, for example as follows:

In a conventional reaction vessel for silver halide precipitation, equipped with an effective stirring mechanism is a Disper medium. This is typically done first in the reaction vessel introduced dispersion medium at least 10 wt .-%, preferably 20 to 80 wt .-% of the dispersion medium in the silver bromoiodide emulsion at the conclusion of the Grain precipitation is present. Since the dispersion medium by Ultra  filtration from the reaction vessel during the silver bromide iodide grain precipitation can be removed, as for example in BE-PS 886 645 and FR-PS 2 471 620 is described, it is possible that the volume of the dispersion medium, which is initially present in the reaction vessel, be the same may be greater than the volume of the silver bromoiodide emulsion, in the reaction vessel at the time of completion of the grain precipitate present. The dispersion medium, first in the Reaction vessel is introduced, preferably consists of water or a dispersion of a peptizer in water, wherein the dispersion medium may optionally contain further components, such as one or more silver halide maturation medium and / or metal dopants, as they will be closer later be written. Is there a peptizer from the beginning, so this is preferably in a concentration of at least 10%, preferably in a concentration of at least 20%, based on the total Peptisationsmittel to complete the Silver bromide iodide precipitation used. Further dispersion medium is added to the reaction vessel with the silver and halide salts set, where appropriate, also supplied by a separate inlet nozzle can be led. According to common practice, the proportion of Dispersion medium, in particular for increasing the ratio on Peptisationsmittel, after completion of the salt addition turned be presented.

A small amount, typically less than 10% by weight of the silver bromide iodide grains used Bromide salts is present in the reaction vessel from the beginning to the bromide ion concentration of the dispersion medium at the beginning of silver bromide iodide precipitation. The dispersion medium in the reaction vessel is practical at the beginning of iodide ions free, since the presence of iodide ions before the simultaneous Introduction of silver and bromide salts the formation of thick and not tabular grains. The expression "of  Iodide ions practically free "means that the amount of iodide ion possibly present is not sufficient Compared to the Bromidionen a separate silver iodide phase to precipitate. Preferably, the iodide concentration in the Reaction vessel before silver salt introduction at less than 0.5 mole% of the total halide ion concentration present held. If the pBr value of the dispersion medium is initially too high high, tabular silver bromoiodide grains are produced, which are comparatively thick and consequently a low one Lead to aspect ratio. As appropriate, it has been proven, the pBr of the reaction vessel at the beginning at or below 1.6, preferably below 1.5. On the other hand, it is the pBr value too low, then the formation of non-tabular silver bromide iodide grains favored. As a result it turned out to be expedient, the pBr value in the reaction vessel on or above 0.6, preferably above 1.1. Like him already The pBr value is defined as the value of the negative Logarithm of bromide ion concentration. The pH value, pCl value, The pI value and the pAg value are the same for the Hydrogen, chloride, iodide and silver ion concentrations Are defined.

During silver halide precipitation, silver, bromide and iodide salts in the reaction vessel according to usual for the Precipitation of Silberbromidiodidkörnern conventional methods introduced. Thus, typically, for example, an aqueous silver salt solution of a soluble silver salt, e.g. B. silver nitrate, in the Reaction vessel simultaneously with the bromide and iodide salts leads. The bromide and iodide salts are also more typical Way in the form of aqueous salt solutions introduced, for. B. in shape aqueous solutions of one or more soluble ammonium, Alkali metal (eg, sodium or potassium), or alkaline earth metal (eg, magnesium or calcium) halide salts. The silver salt is at least initially separated from the bromide and iodide salts are introduced into the reaction vessel. The iodide and bromide salts  may be in the reaction vessel separated from each other or in the form mixture.

With the introduction of silver salt in the reaction vessel is initiated the nucleation stage of grain formation. So will one Population of grain nuclei generated as precipitation centers for Silver bromide and silver iodide are used when the introduction of Silver, bromide and iodide salts is continued. The precipitation of silver bromide and silver iodide on existing grain germs represents the growth stage of grain formation ratio of the tabular grains used in the present invention becomes less due to iodide and bromide concentrations during the growth stage than during the nucleation stage influenced. As a result, it is possible during the growth stage the permissible margin of pBr during concurrent Introduction of silver, bromide and iodide salts above 0.6, preferably in the range of 0.6 to 2.2, in particular of about 0.8 to about 1.6, the last indicated range is particularly advantageous in the case in which a wesent grain nucleation during the introduction of silver, bromide and iodide salts, as in the preparation of highly poly disperse emulsions. Increasing the pBr values to over 2.2 During the growth of the tabular grains leads to a Thickening of the grains, but can be tolerated in many cases while maintaining an average aspect ratio greater than 8: 1.

An alternative method of introducing the silver, bromide and iodide salts in the form of aqueous solutions is the silver, bromide and iodide salts in the form of finely divided silver halide grains suspended in a dispersion medium, at the beginning or during the growth stage. The Grain size is such that it easily Ostwald ripening be subject to larger grain sizes, if any, when they are introduced into the reaction vessel. The maximum  suitable grain size depends on the specific conditions in the From the reaction vessel, such as the temperature and the presence of solubilizing compounds and / or ripening agents. Introduced silver bromide, silver iodide and / or silver bromide iodidkörner. Since silver bromide and / or silver iodide with respect to silver chloride are preferably precipitated, it is also possible Silberchloridbromid- and Silberchloridbromidiodidkörner ver turn. Preference is given to very finely divided silver halide used grains, z. B. grains of a mean diameter of less than 0.1 microns.

Taking into account the pBr requirements discussed, usual concentrations of silver, bromide and iodide salts in the reaction vessel are introduced. For example, solutions can a concentration of 0.01 moles per liter up to saturation concentration be applied. Preferably, however, are Konzen applied from 0.1 to 5 moles per liter. Especially before Partial precipitation techniques are those in which short precipitation Times can be achieved by increasing the speed of Silver and halide salt addition during the manufacturing process. The silver and halide salt introduction can be increased either by increasing the rate at which the dispersion medium and the silver and halide salts are introduced or through Increase in the concentrations of silver and halide salts inside half of the dispersion medium that is introduced. As special it has proved advantageous to increase the speed of the silver and halide salt addition, but the speed of the Introduction below the threshold at which the Formation of new grain germs is favored, d. H. a Re to avoid nucleation, as for example in the US-PS 3 650 757, 3 672 900, 4 242 445, DE-OS 21 07 118, the euro European Patent Application No. 80102242 and in the work of Wey "Growth Mechanisms of AgBr  Crystals in Gelatin Solution ", published in the journal "Photographic Science and Engineering", Volume 21, No. 1, January / February 1977, page 14 et seq. By avoidance the formation of additional grain nuclei after transition into the Growth stage of the precipitation process can be a relative monodisperse tabular silver bromide iodide grain population hold. Emulsions with a coefficient of variation can be used less than about 30%. The coefficient of variation is defined as 100 times the standard deviation of the Grain diameter divided by the mean grain diameter. By intentional promotion of renucleation during Of course, it is also the growth stage of the precipitation process possible, polydisperse emulsions of a considerably higher Produce coefficients of variation.

The concentration of iodide in the invention used Silver bromide iodide emulsions can be prepared by the introduction of Control iodide salts. It can be customary iodide concentrations be turned. Even very small amounts of iodide, z. In sizes range of 0.05 mol% may be advantageous, in particular Advantageously, the inventively used include Emulsions at least about 0.1 mole percent iodide. Silver iodide settles into the tabular silver bromoiodide grains to its sol limit of silver bromide at the temperature of grain formation introduce. Thus, silver iodide concentrations of up to about 40 mole percent in the silver bromide iodide tabular grains Precipitation temperatures of 90 ° C achieve. In practice you can Precipitation temperatures down to near room temperature, for example 30 ° C are applied. In general, it has to be as before proved in part, the precipitation at temperatures of 40 to 80 ° C. perform. In the case of most photographic application areas, it has further proved to be advantageous, the maximum iodide concentration to about 20 mole%, optimally to limit up to about 15 mol%.  

The relative ratio of iodide and bromide salts incorporated into the Reaction vessel to be introduced during the precipitation process, can be a fixed ratio to a substantially the same shaped iodide profile in the tabular silver bromide iodide grains to achieve and on the other hand, the relative ratio, um to achieve different photographic effects.

Thus, special photographic advantages can be achieved be that the proportion of iodide in the annular areas the tabular silver bromoiodide grains of a high aspect ratio compared to the central area of the tabular Grains is increased. For example, the iodide concentrations in the central region at 0 to 5 mol%, at an at least 1 mol% higher iodide concentration in the since union, the center surrounding annular areas, where the iodide concentration in these areas to solubility limit of silver iodide in silver bromide may increase and before preferably up to about 20 mole%, and more preferably up to about 15 mole% is.

According to an advantageous production variant, the iodide or bromide and iodide salt addition to the reaction vessel before Completed completion of the addition of the silver salt, so that excess Halide reacts with the silver salt. This leads to education a shell of silver bromide on the tabular silver bromide iodidkörnern. From the above it follows that the panel shaped Silberbromidiodidkörner the invention used Emulsions a substantially uniform or graded May have iodide concentration profile and that the gradation, if desired, can be controlled to the training of higher iodide concentrations inside the grains or on or near the surface of the tabular silver bromoiodide grains to favor.  

Although the preparation of the silver bromoiodide emulsions with high aspect ratio tabular silver halide grains has been described with reference to a method in which neutral or non-ammoniacal emulsions are the emulsions used according to the invention and their use after all not limited to specific methods of production.

According to an alternative procedure, which is a Improvement over those of US-PS 4,150,994 and from the DE-OS 29 05 655 and 29 21 077 known method is carried out the preparation according to the invention usable silver halide emulsions in such a way that the silver iodide concentration in the reaction is reduced to less than 0.05 moles per liter and in that the maximum size of the silver iodide grains that begin in the reaction container is reduced to less than 0.05 microns.

High tabular silver bromide grain emulsions Aspect ratio without iodide can be further after produce the described method with the omission of iodide. Silver bromide emulsions with tabular silver bromide grains a high aspect ratio can be further example wise also produce a method that is similar to the Method described in the reference "Science et Industries Photographiques, Vol. 33, No. 2 (1962), pages 121-125 becomes. Silver bromide emulsions with a high aspect ratio with a content of in the supervision quadrangular and rectangular Grains can be prepared by the following method: Cube crystal nuclei of an edge length of less than 0.15 microns. While the pAg value of the crystal germ emulsion is maintained at 5.0 to 8.0, the emulsion becomes practical in the absence of non-halide silver ion complex binders left to produce tabular silver bromide grains with an average aspect ratio of at least 8: 1. Further processes for the preparation of silver bromide emulsions with tabular silver bromide grains of a high aspect ratio No iodide content is used in the examples below described.  

The diversity of the invention usable tabular grain silver halide emulsions a high aspect ratio can be illustrated thereby, that, for example, also tabular silver chloride grains Herge that can be placed inside virtually free from both Silver bromide and silver iodide are. Such emulsions can be, for example, after a double inlet process ago in which chloride and silver salts simultaneously in Gegen be introduced from ammonia into a reaction vessel, the contains a dispersion medium. During the chloride salt introduction is the pAg value within the dispersion medium to 6.5 to 10 and the pH is adjusted to 8-10. The presence of ammonia at higher temperatures leads to the formation of thick grains, which is why the precipitation temperatures up to 60 ° C are limited. The process can be used for the production of Silver chloride emulsions with tabular silver chloride grains optimize of high aspect ratio.

It is also possible to prepare the invention Recording Materials Tabular silver halide emulsions To use grains containing at least 50 mol% of chloride stand and have opposite crystal surfaces, which lie in {111} crystal planes and in a preferred form have at least one peripheral edge parallel to a <211 <crystal vector in the plane of one of the main areas lies. Such emulsions can be prepared by Reaction of aqueous silver and chloride halide salt solutions in the presence of a crystal habitus modifying Amount of an amino-substituted azaindene and a peptization by means of a thioether bond.  

Advantageous, usable according to the invention emulsions with panel shaped silver halide grains with a chloride and bromide content in at least the annular grain regions and preferential Wise distributed over the whole grain are those that are can be prepared by maintaining a molar ratio of chloride to bromide ions from 1.6: 1 to about 260: 1 at a Total concentration of halide ions in the reaction vessel of 0.10 to 0.90 normal during the introduction of silver, chloride, Bromide and optionally iodide salts in the reaction vessel. The molar Ratio of silver chloride and silver bromide in the tabular Grains can be between 1:99 and 2: 3.

For the production of novel recording materials suitable silver halide tabular silver emulsions Also, high aspect ratio halide grains can have extremely high average aspect ratios. The average aspect ratios of the tabular grains can be solved by increasing the average or increase mean grain diameter. This can add sharpness benefits lead, but are maximum average grain diameter generally limited by granularity requirements special photographic application. The average or average aspect ratios of the tabular grains also or alternatively increase by reducing the average or average grain thickness. With constant maintenance the silver coating thickness leads to a reduction in thickness the tabular grains in general to improve the Granularity in direct function of the increase of the aspect ratio. As a result, the maximum average aspect ver conditions of the emulsions used in the invention has a function the maximum average grain diameter suitable for special photographic applications are acceptable and achievable baren minimum thickness of the tabular grains that are produced can. The maximum average aspect ratios can be different, depending on the applied precipitation technique and the Halide composition of the tabular grains. The highest  observed average aspect ratios of 500: 1, in the case of tabular grains with photographically suitable Average grain diameters were determined by Ostwald Ripening process of silver bromide grains produced, wherein aspect ratios up to 100: 1, up to 200: 1 or above after Double-entry precipitation process can be produced. The presence of iodide generally reduces the maximum average Aspect ratios that can be realized, but the production is from Z. B. silver bromide iodide tabular grain emulsions an average aspect ratio of up to 100: 1 or 200: 1 or above possible. Furthermore, for example wise aspect ratios of as high as 50: 1 or even 100: 1 im Case of tabular silver chloride emulsions which may Bromide and or iodide.

During the precipitation of the tabular grains may be modifying Be present connections. These connections can be from the beginning be present in the reaction vessel or can with the one or more of the salts may be added by conventional methods. For example, modifying compounds, such as wise compounds of copper, thallium, lead, bismuth, cadmium, Zinc and also chalcogens, such as sulfur, selenium and tellurium gold and precious metals of Group VIII of the Periodic system of the elements during the silver halide Precipitation be present, as it in principle, for example, from the U.S. Patents 1,195,432, 1,951,933, 2,448,060, 2,628,167, 2,950,972, 3 488 709, 3 737 313, 3 772 031 and 4 269 927 and the literature "Research Disclosure", Vol. 134, June 1975, No. 13452 is.

The silver halide emulsions usable according to the invention tabular silver halide grains can be found in the interior during reduction of the precipitation process, for example according to methods as described in the reference "Journal of Photographic Science, Vol. 25, 1977, pp. 19-27.  

The individual silver and halide salts can be added to the reaction be fed by conventional methods via lines, the above the liquid level or below the liquid mirror ends, or by means of a feed device with which the Feeding rates and the pH, pBr and / or pAg values of Reaction vessel contents can be controlled, as example example, from US-PS 3,821,002 and 3,031,304 and the literature "Photographic Correspondence", Vol. 102, No. 10, 1967, page 162 is known. To ensure a rapid distribution of the reaction components Within the reaction vessel, special mixing can be achieved devices are used, as they are for. From US Pat. No. 2,996,287, 3 342 605, 3 415 650, 3 785 777, 4 147 551, 4 171 224, the GB patent application 2 022 431 A, DE-OS 25 55 364 and 25 56 885 and the Reference "Research Disclosure", Vol. 166, February 1978, No. 16662 are known.

In the preparation of the emulsions in the reaction vessel is a Dis submitted. Advantageously, the Disper Sionsmedium from an aqueous Peptisationsmittel suspension. at For example, in the reaction vessel Peptisationsmittelkonzentrationen from 0.2 to about 10 wt .-%, based on the total weight of Emul sion components, present in the reaction vessel. According to usual practice can the concentration of peptizer in the reaction vessel at below about 6%, based on the total weight before and during the Silver halide formation, and the emulsion binders Concentration to achieve optimum coating properties later supplemental binder additions can be adjusted. As purpose Moderately it has appeared, if the emulsion which initially creates is about 5 to 50 g, preferably about 10 to 30 g, peptizations contains medium per mole of silver halide. Additional vehicle can be added later to increase the concentration to beispielswei to bring up to 1000 g per mole of silver halide. Preferably the concentration of carrier in the finished emulsion is included over 50 grams per mole of silver halide. After coating a carrier and drying to form a photographic recording forms materials  the carrier preferably about 30 to 70% by weight of the emulsion layer.

The vehicle, which consists of binder and peptizer exists, can be selected from a variety of carriers commonly used in silver halide emulsions be used. Preferred peptizers are Hydrophilic colloids, alone or in combination with hydrophobic Substances can be used. Suitable hydrophilic peptizations agents may be proteins or protein derivatives, as well as cellulose derivatives, e.g. As cellulose esters, gelatin, z. B. with alkali be traded gelatin, (bone gelatin or skin gelatin) or Acid-treated gelatin (pigskin gelatin), gelatin derivatives, e.g. Acetylated gelatin and phthalated gelatin consist. These and other suitable carriers become closer for example in the reference "Research Disclosure", Vol. 176, December 1978, Item 17643, Section IX.

Such carrier materials, including the hydrophilic Colloids, as well as hydrophobic materials, which also with the hydrophilic colloids can not be used only for the preparation of the emulsion layers of the invention Use recording materials, but also for the production other layers, for example for the production of cover layers, Interlayers and layers under the emulsion layers lie.

The Kornreifung can during the preparation of the silver halide emulsions. When It has proven advantageous if the grain maturation within the reaction vessel during at least the silver bromide iodide grain formation takes place. The maturation can be done by known silver halide solvents are promoted. For example, it is known that an excess of bromide ions, which is present in the reaction vessel, can promote maturation. Thus it is obvious that the bromide  salt solution which is introduced into the reaction vessel itself can promote maturation. However, there may be other ripening be used in the medium and completely in the dispersion medium in Reaction vessel should be present before using the silver and halide salt addition is started or can such maturing agents into the reaction vessel together with one or more of the halo genidsalze, silver salts or peptizers are fed. According to a further variant of the method, the maturing agent added separately during the addition of the halide and silver salts will give. Ammonia, which is a known ripening agent, does not provide a preferred ripening agent for the her position of silver bromide iodide emulsions which can be used according to the invention with the highest realizable sensitivity-granularity ratio The preferred emulsions according to the invention are not ammoniacal and neutral emulsions.

Preferred ripening agents include those which Containing sulfur. For example, thiocyanate salts used, such as the alkali metal salts, especially sodium and potassium as well as ammonium thiocyanate salts. The ripening agents may be in the usual known concentrations be used. Konzen have proven to be particularly advantageous concentrations of about 0.1 to 20 g of thiocyanate salt per mole of silver halide proved. The use of Thiocyanatreifungsmitteln is for example from US-PS 2,222,264, 2 448 534 and 3 320 069 known. On the other hand, for example, also usual Thioether ripening agents are used, as for example from US Pat. Nos. 3,271,157, 3,574,628 and 3,737,313.

The silver halide emulsions according to the invention with tabular silver halide grains are preferably present their use for the production of inventive recording materials for the purpose of removing soluble salts. The removal of the soluble salts can be according to usual be knew methods, eg. B. decantation, filtration and / or Ab frightening and leaching occur, as is closer for example  in the reference "Research Disclosure", Vol. 176, December 1978, Item 17643, Section II.

Washing the emulsions has proven to be particularly advantageous to complete the ripening process of the tabular grains ter precipitation, and to increase the thickness and a Reduction of the aspect ratio of the grains and / or one over to avoid moderate increase in the diameter of the grains. The inventor emulsions which can be used according to the invention can be used with them before being used or dried and stored without sensitizer.

After preparing the tabular silver halo emulsions granules, a shell may be produced to produce nuclear Envelope emulsions are applied, including known methods can be applied. To create the shells on the tabular Silver halide grains may be any photographically usable Silver salts are used. The generation of the sheath can, for example be carried out according to methods as described in US Pat. No. 3,367,778, 3,206,313, 3,317,322, 3,917,485 and 4,150,994 are known. Since over Methods of Sheath Formation The Formation of Tabular Kör not favoring a high aspect ratio, if the Growth of the sheath progresses, the mean aspect ratio decreases from the emulsion. However, in the reaction vessel during the Sheath formation conditions maintained favorable for the Formation of tabular grains, so may preferably a Shell growth occurs at the outer edges of the grains, so that a decrease in the aspect ratio need not be made.

Silver halide tabular core-shell silver halide emulsions genidkörnern high aspect ratio are particularly suitable for generating latent interior images and can be used for position of both negative-working recording materials as well as direct reverse materials.  

Particularly advantageous emulsions are present if at least 70%, optimally at least 90% of the total projected Area of grains of a layer of tabular silver halide come from the specified thickness and diameter criteria and have the specified aspect ratio.

While comparatively smaller amounts of non-tabular Grains in many photographic applications fully accepted are, in order to achieve the full benefits of the invention, the proportions of tabular grains of the specified features be as high as possible. Possibly. can larger tabular silver halide grains by mechanical means from smaller non-board shaped grains in a mixed population of grains according to usual known separation methods are separated, for example by Use of a centrifuge or a hydrocyclone. A hydro Cyclone separation is known, for example, from US Pat. No. 3,326,641.

The silver halide grains of the silver used in the invention Halide emulsions are chemically sensitized. The invention according to emulsions used as well as others for the production Emulsions usable according to the recording materials can be used be chemically sensitized with active gelatin, as example from the book of T.H. James "The Theory of the Photographic Process ", 4th Edition, Macmillan, 1977, pages 67-76 is and / or with sulfur, selenium, tellurium, gold, platinum, palla dium, iridium, osmium, rhodium, rhenium or phosphorus sensi bilubilizing agents or combinations of such sensitization medium, z. At pAg values of 5 to 10, pHs of 5 to 8 and temperatures of 30 to 80 ° C, as more in detail, for example in the reference "Research Disclosure", Volume 120, April 1974, No. 12008, "Research Disclosure", Vol. 134, June 1975, Item 13452 and U.S. Patents 1 623 499, 1 673 522, 2 399 083, 2 642 361, 3,297,447, 3,297,446, 3,772,031, 3,761,267, 3,857,771, 3,565,633, 3,901,714 and 3,904,415 and GB-PS 1,315,755 and 1,396,696 is described. The chemical sensitization may be in Presence of thiocyanate compounds are carried out as they are For example, from US-PS 2,642,361 are known or in counter were sulfur-containing compounds, such as from U.S. Patents 2,521,926, 3,021,215 and 4,054,457.  

As it has proven particularly useful chemically in To sensitize the presence of compounds, which one Suppress fog and increase sensitivity if they are present during chemical sensitization, for example in the presence of azaindenes, azapyridazines, Azapyrimidines, benzothiazolium salts and sensitization with one or more heterocyclic nuclei. Examples for such "finish modifiers" or ripening modifying agents are disclosed, for example, in US Pat. No. 2,131,038, 3,411,914, 3,554,757, 3,565,631 and U.S. Patent 3,901,714, and the CA-PS 778 723 and the book by Duffin "Photographic Emulsion Chemistry ", published by Focal Press, (1966), New York, pp. 138-143 known.

The emulsions may additionally or alternatively be subjected to a reduction sensitization, for example with hydrogen, as disclosed, for example, in US Pat. No. 3,891,446 and 3,984,249 is known by low-level treatment pAg (eg less than 5) and / or high pH value (eg greater than 8) or by using Reducing agents, such as stannous chloride, thiourea dioxide, polyamines or amine boranes, such as for example the reference "Reserach Disclosure", Volume 136, August 1975, No. 13,654 and U.S. Patents 2,983,609, 2,518,698, 2,739,060, 2,743,182, 2,743,183, 3,026,203 and 3,361,564. When Advantageously, a Oberflächenensen has usually tion, including a sub-surface Sensitization, as described more closely in, for example, the US PS 3,917,485 and 3,966,476.  

Apart from a chemical sensitization, he will According to the invention used emulsions also a spectral Subjected to sensitization. It is particularly useful proved to spectral sensitizing to use an absorption maximum in the blue and minus blue, d. H. green and red parts of the visible spectrum to have. Furthermore, in special applications spectral sensitizing dyes are used, which is the spectral To improve response beyond the visible spectrum assets. Thus, for example, advantageously infra red absorbing spectral sensitizers are used.

For the spectral sensitization of the invention used Silver halide emulsions can be used in a wide variety of classes use of spectral sensitizing compounds, including the class of polymethine dyes, which include cyanine, merocyanine, complex cyanine and complex merocyanine dyes (i.e., tri-, Tetra- and polynuclear cyanines and merocyanines), as well as also dyes from the group of oxonols, hemioxonols, styryl, Merostyryle and streptocyanines.

Among the useful spectral sensitizing cyanine dyes For example, those include two, the one about a methine group or methine grouping related basic hetero have cyclic cores derived from quaternary Quinolinium, pyridinium, isoquinolinium, 3H-indolium, Benz [e] indolium, oxazolium, thiazolium, selenazolium, imi dazolium, benzoxazolium, benzothiazolium, benzoselenazolium, Benzimidazolium, Naphthoxazolium, Naphthothiazolium, Naphtho selenazolium, thiazolinium, dihydronaphthothiazolium and  Pyrylium, oxazolinium, thiazolinium, selenium azolinium, imida zolinium and imidapyrazinium salts.

The spectral sensitizing merocyanine dyes include for example, those containing a basic heterocyclic Cyanine type core having an acidic core are connected with each other via a methine dough, with the acidic nucleus, for example, can be derived from barbituric acid, 2-thiobarbituric acid, rhodanine, hydantoin, 2-thiohydantoin, 4-thiohydantoin, 2-pyrazolin-5-one, 2-isoxazolin-5-one, indan-1,3-dione, Cyclohexane-1,3-dione, 1,3-dioxane-4,6-dione, pyrazoline-3,5-dione, Pentane-2,4-dione, alkylsulfonylacetonitrile, malononitrile, iso quinolin-4-one and chroman-2,4-dione.

It may contain one or more spectral sensitizing dyes be used. They are dyes with sensitizing maxima at wavelengths across the entire visible spectrum and with very Many different spectral sensitization curves known. The choice and the relative proportions of the dyes too depend on the area of the spectrum for which one Sensitivity is sought and of the form of the desired spectral sensitivity curve. Dyes with each other overlapping spectral sensitivity curves often result in combination with each other to a curve in which the sensitive at each wavelength in the region of overlap approximately equal is the sum of the sensitivities of the single color substances. Thus, it is possible to use combinations of dyes to use different maxima to make a spectral sensitive curve with a maximum between the sensitization maxima to reach the individual dyes.

Also usable are combinations of spectral sensitizing Dyes that cause supersensitization, d. H. a spectral sensitization, which in best. spectral Be range is greater than the sensitization resulting from a  determined concentration of one of the dyes alone or greater than the sensitization resulting from the additive effect of the dyes would result. A supersen sensitization can be made with selected combinations of spectral sensitizing dyes as well as other additives, for example, stabilizers and antifoggants, Ent accelerators or development inhibitors, coating aids, brighteners and antistatic compounds to reach. Reference is made, for example, to the work Gilmsn's Review of the Mechanisms of Supersensitization, published in the journal "Photographic Science and Engi neering ", Vol. 18, 1974, pages 418-430.

Spectral sensitizing dyes can also do the emulsions influence in a different way. So can spectral sensitizing Dyes further, for example, the function of anti fogging agents or stabilizers, development accelerators or development inhibitors and halogen acceptors or Elek exert a tronenakzeptoren, as for example from the US-PS 2,131,038 and 3,930,860 is known.

Typical spectral sensitizing dyes for sensitization the silver halide emulsions used in the invention for example, in the reference "Research Disclosure", Vol. 176, December 1978, Item 17643, Section III.

The dyes used for spectral sensitization can be used in the usual known concentrations. To the To take full advantage of the present invention, it has proved to be advantageous when from the surfaces of tabular silver halide grains spectrally sensitizing Dye is adsorbed in an optimal amount, d. H. in an amount sufficient to be at least 60% of the maximum Photographic sensitivity brought about by the Grains under recommended exposure conditions  can be. The optimal amount of used in the individual case Dye or dyes used depends on the one or the other Dyes itself as well as the size and the aspect ratio of the grains.

It is well known that optimum spectral sensitivity with organic dyes by about 25 to 100% or higher single-layer coating available throughout standing surface areas of surface-sensitive silver halide grains is achieved. Reference is made in this regard for example, on the work of West and employees "The Adsorption of Sensitizing Dyes in Photographic Emulsions", published in Journal of Phys. Chem., Vol 56, page 1065, 1952, further to the work of Spence and Employees "Desensitization of Sensitizing Dyes", published in the reference "Journal of Physical and Colloid Chemistry", Volume 56, No. 6, June 1948, pages 1090-1103 and the US-PS 3 979 213. Optimal dye concentrations can be, for example Wise to find methods that are described in the book by Mees "Theory of the Photographic Process, pages 1067-1069 become.

Although in the case of silver bromide and silver bromoiodide emulsions, which are intended for recording blue light, the natural ones Blue sensitivity of the emulsions is exploited, it is a special feature of the present invention that essential Benefits from the use of spectral sensitization even if theirs can be drawn major absorption in the spectral region, in the emulsion has its natural sensitivity. Let it be For example, special advantages through the use of im blue region of spectral sensitizing dyes. So it has been shown that even if it is at the he According to the invention used emulsions to silver bromide and silver  is a high aspect ratio bromide emulsion, very high sensitivity increases can be achieved when spectral for spectral sensitization in the blue region sensitizing dyes are used. Is intended Recording materials according to the invention with light of their natural exposure range, so can Further sensitivity advantages by increasing the thickness of the tabular grains can be achieved.

For example, it may be advantageous to control the grain thickness, such as described above, increase when the recording material intended for the image transmission method.

According to a particularly advantageous embodiment of the invention Thus, the recording material has one or more blue sensitized silver bromide or silver bromoiodide emulsions in which the tabular grains have a thickness of less than 0.5 microns and a diameter of at least 0.6 microns have a mean aspect ratio of greater than 8: 1, preferably at least 12: 1, with at least 50% the total projected area of silver halide grains the emulsion, in particular at least 70% and in optimal Make at least 90% of the tabular silver halide grains come from.

For blue sensitization of the invention used Silver halide emulsions, especially silver bromide and silver Bromidiodide emulsions can be known spectrally known classes sensitizing dyes are used. Preferably ver used, in the blue region spectral sensitizing dyes are polymethine dyes, eg. Cyanines, merocyanines, hemicyanines, Hemioxonols as well as Merostyryle. The most favorable in the individual case, let in the blue area spectral sensitizing dyes  choose based on their absorption characteristics. there There are also general structural relationships that exist in the Selection of suitable sensitizers should be considered can. In general, it has been shown that the shorter the Methine chain is the shorter the wavelength of sensitization maximums is. The existing cores also influence the Absorption. The introduction of condensed rings to the Cores favor the absorption of longer wavelengths. Also, substituents can ver the absorption characteristics ver to change. In the following formulas, unless otherwise stated is alkyl groups, preferably 1 to 20 carbon atoms, in particular 1 to 8 carbon atoms and aryl groups preferably 6 to 15 carbons, wherein the aryl groups preferably consist of phenyl or naphthyl groups.

Preferably usable, sensitizing in the blue spectral range Cyanine dyes are monomethine cyanines. In general, however can be used in an advantageous manner, in the blue area spectral sensitizing cyanine dyes by the following Play back formula (I).

in which mean:
Z ¹ and Z ² , which may have the same or a different atom, in each case the atoms necessary for the completion of a basic heterocyclic nitrogen-containing nucleus, these nuclei being able to be derived, for example, from the oxazoline, oxazole, Benzoxazole, naphthoxazoles (e.g., naphtha [2,1-d] oxazole, naphtho [2,3-d] oxazole, and naphtha [1,2-d] oxazole), thiazoline, thiazole, benzothiazole, naphthothiazoles, (e.g. Naphtho [2,1-d] thiazole), thiazoloquinolines (e.g., thiazolo [4,5-b] quinoline), selenazoline, selenazole, benzoselenazole, naphthoselenazoles (e.g., naphtho [1,2-d ] selenazole), 3H-indole (e.g., 3,3-dimethyl-3H-indole), benzindoles (e.g., 1,1-dimethylbenz [e] indole), imidazoline, imidazole, benzimidazole, naphthimidazoles (e.g. B. Naphth [2,3-d] imidazole), pyridine and quinoline, wherein the cores may optionally be substituted by an upper several sub-substituents, such as H ydro groups and / or halogen atoms, eg. As fluorine, chlorine, bromine and iodine atoms, further alkyl groups or substituted alkyl groups, for. For example, methyl, ethyl, propyl, isopropyl, butyl, octyl, dodecyl, octadecyl, 2-hydroxyethyl, 3-sulfopropyl, carboxymethyl, 2-cyanoethyl or trifluoromethyl or optionally substituted Aryl groups, e.g. Phenyl, 1-naphthyl, 2-naphthyl, 4-sulfophenyl, 3-carboxyphenyl or 4-biphenyl or alkyl groups, e.g. B. benzyl and phenethyl groups or alkoxy groups, for. For example, methoxy, ethoxy or iso propoxy groups or aryloxy groups, eg. As phenoxy or 1-naphthoxy groups or further alkylthio groups, for. For example, methylthio and ethylthio groups or arylthio groups, e.g. Phenylthio, p-tolylthio and 2-naphthylthio groups, further methylenedioxy, cyano, 2-thienyl, styryl, amino or substituted amino groups, e.g. Anilino, dimethylamino, diethylamino and morpholino groups or finally acyl groups, e.g. B. carboxy groups, for example acetyl and benzoyl groups and sulfo groups;
R ¹ and R ² , which may have the same or different meaning, alkyl, aryl, alkenyl or aralkyl groups which may be optionally substituted, for. As carboxymethyl, 2-hydroxyethyl, 3-sulfopropyl, 3-sulfobutyl, 4-sulfobutyl, 4-sulfo phenyl, 2-methoxyethyl, 2-sulfatoethyl, 3-Thiosulfatopropyl-, 2-phosphonoethyl -, chlorophenyl and bromophenyl groups;
R ^{3 is} a hydrogen atom;
R ⁴ and R ⁵ each represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;
p and q = 0 or 1, it being understood that preferably p and q are not both = 1;
m = 0 or 1, provided that when m = 1, p and q = 0 and at least one of the rings completed by Z ¹ and Z ^{2 is} an imidazoline, oxazoline, thiazoline or selenazoline ring;
A is an anionic group;
B is a cationic group and
k and 1 = 0 or 1, depending on whether ionic substituents are present or not. Ggf, R ¹ and R ³ , R ² and R ⁵ or R ¹ and R ² (especially when m, p and q = 0) may together represent the atoms required to complete an alkylene bridge.

Typical blue-sensitive cyanine which can be used according to the invention Dyes are those listed in Table I below Dyes.

Table I

1. 3,3'-diethylthiacyanine bromide

2. 3-Ethyl-3'-methyl-4'-phenylnaphtho [1,2-d] thiazolothiazolinocyanine bromide

3. 1 ', 3-diethyl-4-phenyloxazolo-2'-cyanine iodide

4. Anhydro-5-chloro-5'-methoxy-3,3'-bis (2-sulfoethyl) thiacyanine hydroxide, triethylamine salt

5. 3,3'-bis (2-carboxyethyl) thiazolinocarbocyanine iodide

6. 1,1'-Diethyl-3,3'-ethylbenzimidazolocyanine iodide

7. 1- (3-ethyl-2-benzothiazolinylidene) -1,2,3,4-tetrahydro-2-methylpyrido [2,1-b] benzothiazolinium iodide

8. Anhydro-5,5'-dimethoxy-3,3'-bis (3-sulfopropyl) thiacyanine hydroxide, sodium salt

Particularly advantageous, in the blue region spectrally sensitizing merocyanine dyes are Zeromethinmerocyanine (apo-merocyanines). However, merocyanine dyes suitable for bluesensitization can be represented by the following general formula (II):

in which mean:
Z is the atoms necessary to complete a heterocyclic nucleus, corresponding to Z ¹ or Z ² of formula (I);
R is a group as indicated for R ¹ or R ² of formula (I);
R ⁴ and R ⁵ each represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or an aryl group, e.g. B. a phenyl or naphthyl group;
G ^{1 is} an optionally substituted alkyl group, an optionally substituted aryl group or an aralkyl, alkoxy, aryloxy, hydroxy or optionally substituted amino group, for. B. groups of the type indicated in formula (I);
G ^{2 is} a group as indicated for G ¹ , with the proviso that G ² additionally may be a cyano, alkyl or arylsulfonyl group or a group of the formula

with the proviso that G ² together with G ^{1 can} also stand for the atoms which form a cyclic acidic nucleus derived, for example, from a 2,4-oxazolidinone (for example 3-ethyl-2,4-oxazolidinedione ), 2-thiazolidinedione (e.g., 3-methyl-2,4-thiazolidinedione), 2-thio-2,4-oxazolidinedione (e.g., 3-phenyl-2-thio-2,4-oxazolidinedione), rhodanine , z. 3-ethylrhodanine, 3-phenylrhodanine, 3- (3-dimethylaminopropyl) rhodanine and 3-carboxymethylrhodanine, hydantoin (e.g., 1,3-diethylhydantoin and 3-ethyl-1-phenylhydantoin), 2-thiohydantoin (e.g. B. 1-ethyl-3-phenyl-2-thiohydantoin, 3-heptyl-1-phenyl-2-thiohydantoin and 1,3-diphenyl-2-thiohydantoin), 2-pyrazolin-5-one, e.g. B. (3-methyl-1-phenyl-2-pyrazolin-5-one, 3-methyl-1- (4-carboxybutyl) -2-pyra zolin-5-one and 3-methyl-2- (4-sulfophenyl ) -2-pyrazolin-5-one, 2-isoxazolin-5-one (eg 3-phenyl-2-isoxazolin-5-one), 3,5-pyrazolidinedione (e.g. Diethyl-3,5-pyrazolidinedione and 1,2-di-phenyl-3,5-pyrazolidinedione), 1,3-indanedione, 1,3-dioxane-4,6-dione, 1,3-cyclohexanedione, barbituric acid (e.g. 1-ethylbarbituric acid and 1,3-diethylbarbituric acid) and 2-thiobarbituric acid (e.g., 1,3-diethyl-2-thiobarbituric acid and 1,3-bis (2-methoxyethyl) -2-thiobarbituric acid);
r and n = 0 or 1, provided that when n = 1, Z is the atoms necessary to complete an imidazoline, oxazoline, selenazoline, thiazoline, imidazoline, oxazole or benzoxazole nucleus, or G ¹ and G ² do not represent a cyclic system.

Some typical blue-sensitizing merocyanine dyes are shown in the following Table II.  

Table II

1. 5- (3-ethyl-2-benzoxazolinylidene) -3-phenylrhodanine

2. 5- [1- (2-carboxyethyl) -1,4-dihydro-4-pyridinylidene] -1-ethyl-3-phenyl-2-thiohydantoin

3. 4- (3-ethyl-2-benzothiazolinylidene) -3-methyl-1- (4-sulfophenyl) -2-pyrazolin-5-one, potassium salt

4. 3-carboxymethyl-5- (5-chloro-3-ethyl-2-benzothiazolinylidene) rhodanine

5. 1,3-diethyl-5 - [(3,4,4-trimethyloxazolidinylidene) ethylidene] -2-thiobarbituric acid

Advantageously useful blue-sensitizing hemi-cyanine dyes can be represented by the following formula (III):

wherein Z, R and p have the same meaning as given in formula (II) and wherein
G ³ and G ⁴ , which may have the same or a mutually different meaning, in each case an optionally substituted alkyl or optionally substituted aryl radical or an aralkyl radical, such as those given for the nuclear substituents of the formula (I) or G ³ and G ⁴ together form the atoms required to complete a ring system derived from a cyclic secondary amine, e.g. Pyrrolidine, 3-pyrroline, piperidine, piperazine (e.g., 4-methylpiperazine and 4-phenylpiperazine), morpholine, 1,2,3,4-tetrahydroquinoline, decahydroquinoline, 3-azabicyclo [3,2,2] nonane , Indoline, azetidine and hexahydroazepine;
L ¹ to L ^{4 are} each a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or an optionally substituted aryl group or each two L ¹ , L ² , L ³ and L ^{4 are} the atoms necessary to complete an alkylene or carbocyclic bridge ;
n = 0 or 1 and
with the further proviso that A and k are as defined for formula (I).

Typical, easily used, bluesensitizing Hemicyanine dyes are those as shown in the following table (III) are indicated:

Table III

1. 5,6-Dichloro-2- [4- (diethylamino) -1,3-butadien-1-yl] -1,3-diethylbenzimidazolium iodide

2. 2- {2- [2- (3-Pyrrolino) -1-cyclopenten-1-yl] ethenyl} 3-ethylthiazolinium perchlorate

3. 2- (5,5-dimethyl-3-piperidino-2-cyclohexene-1-ylidene-methyl) -3-ethylbenzoxazolium perchlorate

Advantageous, employable according to the invention bluesensitizing hemioxonol dyes are those of the following formula (IV):

wherein G ¹ and G ^{2 have} the meaning already given in connection with the formula (II) and wherein further
G ³ , G ⁴ , L ¹ , L ² and L ^{3 have} the meaning given in connection with the formula (III) and wherein furthermore
n = 0 or 1.

Typical Bluesensitizing used in the invention Hemioxonol dyes are as shown in Table IV below indicated dyes:

Table IV

1. 5- (3-Anilino-2-propen-1-ylidene) -1,3-diethyl-2-thiobarbituric acid

2. 3-Ethyl-5- (3-piperidino-2-propene-1-ylidene) rhodanine

3. 3-Allyl-5- [5,5-dimethyl-3- (3-pyrrolino) -2-cyclohexene-1-ylidene] rhodanine

Blue-sensitizing merostyrene dyes which can be used according to the invention can be represented by the following formula (V):

wherein G ¹ , G ² , G ³ and G ⁴ and n have the meaning already given in connection with the formula (IV).

Typical Bluesensitizing used in the invention Merostyryl dyes are those shown in the following table (V) listed dyes:

Table V

1. 1-cyano-1- (4-dimethylaminobenzylidene) -2-pentanone

2. 5- (4-Dimethylaminobenzylidene-2,3-diphenylthiazolidin-4-one-1-oxide

3. 2- (4-Dimethylaminocinnamylidene) thiazolo [3,2-a] benzimidazol-3-one

The spectral sensitization of the silver halide grains can at any point in the emulsion production. Especially Usually, the spectral sensitization takes place in itself known manner after completion of the chemical sensitization. However, the spectral sensitization may alternatively be the same can be done early with the chemical sensitization, before the chemical sensitization can and can be carried out even started before the silver halide precipitation is finished, as for example from US-PS 3,628,960 and 4 225 666 is known. So it can, as in US-PS 4,225,666 be particularly advantageous, the introduction of the spectral sensitizing dye into the emulsion, so that part of the spectral sensitizing dye already is present before the chemical sensitization and such that the remainder is added after chemical sensitization becomes. Furthermore, unlike the teaching of the US PS 4 225 666 the spectral sensitizing Dye may be added to the emulsion after 80% of the silver halides have been precipitated. The sensitization can by a pAg setting, including the change in the pAg Value, which completes one or more cycles during the increased chemical or spectral sensitization. In this case, for example, to proceed as in the  Reference "Research Disclosure", Volume 181, May 1979, No. 18155 is described in more detail.

The invention is u. a. the Erkennis based that silver halide high tabular silver halide grain size emulsions Aspect ratio of the specified type better sensitivity Granularity ratios when the silver halide grains chemically and spectrally sensitized, known as usual Silver halide emulsions of corresponding halide content.

It is generally known that silver bromide iodide emulsions the best possible sensitivity-granularity ratios he to aim. As a result, such emulsions in the Rule for the preparation of phographic recording materials used by camera sensitivity. Optimal chemical and spectral sensitized silver bromide and silver bromoiodide emulsions with high aspect ratio tabular silver halide grains surprisingly have improved sensitivity granules keits ratios compared to the best known Sensitivity-granularity ratios, which at Belich could be achieved in the minus blue region of the spectrum. Generally speaking, optimally chemically and spectrally sensitized Silver halide emulsions containing tabular silver halide grains of high aspect ratio when spectral in one area Sensitization and beyond the range of natural sensation significant improvements the sensitivity-granularity relationship in relation to customary known emulsions of a corresponding halide content. Improve sensitivity-granularity ratios arise especially in the case of silver bromide and silver bromide iodide emulsions containing tabular silver halide grains having a high aspect ratio compared to the green and / or red Spectrally sensitized areas of the spectrum and ent be exposed to speaking light. Improvements of the sensation Lightness Grain Ratios in Natural Sensitivity  range of the spectrum, z. In the blue region of the spectrum, can also be realized if the invention ver used emulsions with blue sensitizing color sensitized substances and with appropriate conventional emulsions be compared.

According to an advantageous embodiment of the invention, spectral sensitizers can be incorporated into the emulsions prior to chemical sensitization. Similar results can in some cases also be achieved by incorporating other absorbable substances, such as so-called "finishing modifiers", into the emulsions prior to the chemical sensitization. Regardless of whether prior introduction of absorbents has been made or not, it has been found to be advantageous to use thiocyanates during chemical sensitization in concentrations of about 2 × 10 ^-3 - 2 mol%, based on silver, as in the US Pat. PS 2 642 361, use. However, other ripening agents may be used during chemical sensitization.

Furthermore, according to another embodiment, in Kom Combination with one or both of the above method or separately can be carried out in front of Partially the concentration of silver and / or halide be adjusted immediately before or during the chemical sensitization. So can be soluble Silver salts, such as silver acetate, silver trifluoro acetate and silver nitrate, as well as silver salts, which can deposit on the grain surfaces, such as silver thiocyanate, silver phosphate, silver carbonate.

Also, finely divided silver halide grains, e.g. B. of silver bromide, iodide and / or chloride resulting in Ostwald ripening on the tabular grain surfaces are introduced For example, during chemical sensitization introduce a Lippmann emulsion.  

The chemical sensitization of the spectrally sensitized tabular grains may also be attached to one or more ordered discrete locations of the tabular grains. It is believed that the preferred adsorption of spectral sensitizing dye to the crystallographic top surfaces, which are the major surfaces of the tabular silver halide grains form, a selective chemical sensitization other crystallographic surfaces of the tabular grains allows.

The preferred chemical sensitizers for the highest achievable sensitivity granularity Conditions are gold and sulfur sensitizers, gold and sulfur sensitizers Selenium sensitizers and gold, sulfur and selenium sensitizers capacitors. According to a particularly advantageous embodiment of the Invention comprise the emulsions according to the invention, in particular Silver bromide and silver bromoiodide emulsions, a sulfur, Selenium and / or tellurium sensitizer, not solid can be adjustable, and gold, which can be determined. The emulsions furthermore obtain normally detectable concentrations thiocyanate, although the concentration of thiocyanate in the finished emulsion can be greatly reduced due to common Washing process.

Possibly. For example, the tabular silver bromide and silver bromide iodide grains also another silver salt on their upper surface deposited, z. As silver thiocyanate or a other silver halide of different halide content, e.g. B. Silver chloride or silver bromide, the other silver salt possibly also be present in undetectable concentrations can.

Although it is not necessary to get all the benefits are the emulsions of the invention come to light, are but preferably the emulsions usable according to the invention  optimally chemically and spectrally sensitized. This means, that they preferably have sensitivities of at least 60% of the achieve maximum logarithmic sensitivity for the grains in the spectral region of sensitization below the recommended conditions of use and development conditions is reachable. The logarithm of the sensitivity is included defined as 100 (1-log E), where E is in lux-seconds a density of 0.1 above the veil is measured. Are the Characterized silver halide grains of an emulsion layer, so it is possible, due to further product analysis too determine if an emulsion layer of a recording material practically optimal chemical and spectral compared to comparison of commercially available products from other manufacturers sensitized or not.

By silver halide precipitation, washing and Sensibili tion, as described above, emulsions can be prepared further customary photographic additives are incorporated, whereupon they by conventional methods for the production of recording materials can be used, for example for the production of recording materials for black and white photography or Color photography.

The z. B. for the production of silver images certain erfindungsge According to recording materials may ge in such an extent hardens that the need of introducing additional Curing agent is eliminated during the development process. Thereby an increased silver covering power is possible compared to photographic recording materials corresponding in Hardened and developed, but for their production, however non-tabular silver halide emulsions or silver halide low tabular silver halide emulsions  Aspect ratio can be used. Especially it is possible the emulsion layers with the tabular silver halide high aspect ratio and other hydrophilic colloid granules layers of black and white photographic materials in one To harden dimensions sufficient to swell the layers less than 200%, with the percentage swelling is determined by (a) incubating the photo for 3 days graphic recording material at 38 ° C and 50% relative Humidity, (b) measuring the layer thickness, (c) 3 minutes long immersion of the photographic material in distilled water at 21 ° C; and (d) measuring the change in Layers thick. Although the curing of the recording materials, which are intended for the production of silver images, up to To an extent that the addition of curing agents in development Solutions is not required, is particularly advantageous needs however, such hardening does not occur, d. H. the invention Proper recording material can also be used in other conventional ways be hardened. For example, it can be beneficial To apply curing agent in development solutions, as example from the reference "Research Disclosure", Vol. 184, August 1979, no. 18431, § K, is known, in particular on the development of radiographic recording materials refers.

Typical suitable curing agents (pre-curing agent) are z. B. in the reference "Research Disclosure", Volume 176, Dec. 1978, No. 17 643, step X described.

The emulsions may further contain conventional stabilizers, anti fogging agents, means for preventing kinks, Stabilizers for latent images and other common additives be spent. Possibly. Such additives can also be layers  which are adjacent to the emulsion layers. Many of the known, to protect the emulsions described usable antifoggants which, when used in the Emulsions are also effective in developers be brought. They can be, for example, like in the book by C.E. Mees, "The Theory of the Photographic Process ", 2nd Edition, Publisher Macmillan, 1954, pages 677-680 specified, classify.

In order to protect the emulsion layers, thus conventional known stabilizers and antifoggants are used, as they are known for example from the literature "Research Disclosure", Vol. 176, December 1978, Item 17643, Section VI.

The materials for producing inventive recording materials used, for example, against over a fogging and desensitization, caused by traces of metals, such as copper, lead, Tin, iron by incorporation of usual additives, the be used for this purpose.

In the case where aldehyde type curing agents are used, For example, the emulsion layers can be coated with conventional antifoggants to be protected.

Besides sensitizers, hardeners, antifoggels agents and stabilizers can give the emulsions be incorporated into other acquisitions. The selection of such additives depends on the field of application of the recording to be made materials. A variety of additives that may affect the emulsions can be added, is described in the literature "Research Disclosure", Vol. 176, December 1978, Item 17643.  

Possibly. can the emulsions z. As incorporated optical brightener as described in § V of the cited reference under no. 17643 indicated. Finally, in the emulsion layers or in this adjacent layers also absorbing or light scattering substances are housed, as example be given in § VIII of the cited reference. Also, coating aids may be added to the emulsions and / or plasticizers and lubricants, as they are in paragraphs XI and XII of the reference cited be listed. The recording materials can the other, for example, antistatic layers as indicated in paragraph XIII of the reference. For introducing the additives into the emulsions may further For example, methods such as those described in Paragraph XIV the reference is given. Further, for example Matting agents as set forth in paragraph XVI. Developer compound and development modifier can for example as indicated in paragraphs XX and XXI become. Are the photographic materials for intended for radiographic purposes, so for the production of the recording materials used emulsions and others Layers of radiographic recording materials under consideration in the reference "Research Disclosure", Volume 176, December 1978, No. 18431, indicated measures herge be presented. Finally, the fiction for the invention emulsions used according to recording materials, if necessary together with other conventional silver halide emulsions and Coating compositions by production of cover layers and Zwi layers according to customary known methods on carriers applied and dried, as for example in Paragraph XV of the cited reference is described.  

Possibly. can be used according to the invention for the production of photographic Recording materials usable silver halide emulsions with tabular silver halide grains of high aspect Ratio according to the methods of the prior art with each other or mixed with other conventional silver halide emulsions to meet special requirements. So can at For example, different emulsions are mixed together, to achieve a certain characteristic curve. Furthermore Mixtures of emulsions can be prepared at the exposure and development achievable maximum densities increase or decrease the achievable minimum densities increase or decrease and / or the shape of the charac teristics curves between the shoulder area and the sag area modify. This means that the invention usable emulsions, for example with conventional silver halide emulsions, as described for example in the Reference "Research Disclosure", Volume 176, December 1978, No. 17643, Paragraph I, can be mixed. The emulsions can be advantageously as in the subparagraph F of paragraph I are mixed together. Will a comparison fine-grained silver chloride emulsion with one of the described Emulsions used according to the invention, in particular a silver bromide iodide emulsion mixed or adjacent to an emulsion layer arranged from one of the described fiction, produced according to emulsions used, so can one achieve further contrast and / or sensitivity increase, d. H. a further increase in the sensitivity-granularity ratio as disclosed in U.S. Patent Nos. 3,140,179 and 3,152,907.  

Instead of using mixed emulsions as described above, usually a similar effect can also be achieved achieve that the emulsions, rather than ver together mixed, applied in the form of separate layers on a support become. So it is known, for example from the book of Zelikman and Levi "Making and Coating Photographic Emulsions", Publisher Focal Press, 1964, pages 234-238, U.S. Patent 3,662,228 and GB-PS 923,045 that by applying separate emulsions Layers on a support to increase the exposure latitude. It is also well known that increased photo to achieve graphic sensitivities by more sensitive and less sensitive silver halide emulsions in the form of separate layers can be applied to a support, instead of mixing them together. In a typical way in such cases, the more sensitive emulsion such on the Carrier applied that they for the exposure of the recording materials used light source is closer than the less sensitive emulsion layer. Possibly. not only two can three or more layers of different sensitivity be arranged one above the other. Also to such layers Arrangements can be described silver halide emulsions with tabular silver halide grains in an advantageous manner use.

The described tabular silver halide emulsions grains may possibly be with others for making recording materials suitable emulsions and coating compositions usual, suitable for photographic purposes carrier applied be used, for example, on carriers made of polymer films, paper, Metal foils, glass and ceramic substrates, which may be a or more adhesive layers to increase the adhesion of the To improve layers on the substrate and, if necessary, the  antistatic properties, dimensional properties, abrasion characteristics, the hardness, the friction properties, the light carcase characteristics and other characteristics of the carcass surface to improve. For the preparation of inventive Auf Drawing materials suitable supports are thus known Layer support, which are described for example in more detail the reference "Research Disclosure", Volume 176, December 1978, No. 17643, section XVII.

Although the emulsions are typically more endless in shape Layers on support with opposing planar Surfaces are applied, this does not apply to the case his. Rather, the emulsions, for example, in the form of layer segments on planar supports Surfaces are applied. Should the emulsion layers Form segments, so it has proved to be advantageous so-called. to use microcellular carriers. Such microcellular carriers are described in more detail, for example, in the PCT application WO 80/01614, published on August 7, 1980 and in the BE-PS 881 513. The microcells can be for example a width from 1 to 200 microns and a depth of up to 1000 microns point. It has proved to be advantageous in general if the microcells have a width of at least 4 microns and a depth of less than 200 microns with optimal dimensions For example, in the field of black and white photography then when the microcells are about 10 to 100 microns wide and are deep. This is especially true in the event that the to be enlarged photographic image to be produced.

The photographic recording materials of the invention Granules are exposed imagewise in the usual manner. Ver In this regard, the reference "Research Dis closure ", Vol. 176, December 1978, Item 17643, Paragraph XVIII.  

The effects achievable according to the invention come in particular then when the imagewise exposure of the recording materials with electromagnetic radiation within the Range of the spectrum takes place in the existing spectral Sensitizers have their absorption maxima.

For the exposure of Recording materials can be conventional radiation or light sources are used, for example, laser beams. In the Radiation may also be a coherent or a non-coherent radiation act. The exposures can be other at normal, elevated or reduced temperature and / or pressure conditions. Furthermore, Expo with high or low intensity radiation be guided, with the exposures continuously or can also be carried out intermittently and wherein the Exposure times in the millisecond or microsecond range lie or can be up to minutes. Furthermore, you can For example, solarizing exposures occur within suitable response ranges determined by conventional methods may be described in more detail, for example the book by T.H. James "The Theory of the Photographic Process", 4th edition, Macmillan, 1977, chapter 4, 6, 17, 18 and 23.

The development of the exposed recording materials after the Invention can be carried out by customary known methods, and although using an aqueous alkaline medium in counter were one or more developer compounds used in the alkaline development medium and / or in the recording material can be accommodated.  

After forming a silver image in the recording material For example, the recording material can be prepared by conventional methods be fixed. It has been shown that emulsion layers the described tabular silver halide emulsions Silver halide grains fix in a shorter, than normal allow usual time span. This allows the gas Accelerate development process.

The recording materials according to the invention can for the preparation of dye images by use of Ent winders with color formers, such as color couplers, can be used, as for example from the literature "Research Disclosure", Vol. 176, December 1978, Item 17643, Section VII is known. When using color couplers for the production In the color images, the developer includes a color developer binding, z. In the form of a primary aromatic amine, the in its oxidized form with the coupler to produce a Image dye is able to couple.  

The dye-forming couplers may further also accommodated in the color photographic recording material itself become. The color couplers can be used in different quantities Achieving different photographic effect used become. For example, the color coupler concentration can be in relation to silver coating thickness diminish to less than those normally in comparatively sensitive layers and medium sensitivity layers used.

The dye-forming coupler can be known in the usual Be selected such that subtractive primary (i.e. yellow, purple and blue-green) image dyes are generated. The color couplers are preferably not diffusing, colorless compounds. Such couplers, in which are, for example, 2- and 4-equivalent couplers may, for example, consist of open-chain ketomethylene, Pyrazolone, pyrazolotriazole, pyrazolobenzimidazole, phenol and Naphthol couplers that are described in a variety of references be written. Possibly. can dye-forming coupler ver different reaction rates in individual or separate Layers are used to achieve certain desired effects achieve.

Advantageously, such dyes can also be supplied Couplers are used which are free in coupling connections which perform photographic functions, for example Development inhibitors or development accelerators, bleaching accelerator, developer compounds, silver halide solution agent, toner, hardener, fog, antifoggant, so-called competition coupler chemical or spectral sensitizing compounds and desensitizing acting connections. Thus, the Auf Drawing materials, for example, so-called Entwicklungsinhibi contain releasing couplers (DIR couplers), which in one Variety of references will be described. Also can one Inventive recording material, for example Ver  containing compounds which do not themselves provide dyes, However, by coupling the various compounds freizu ability, the photographic functions, as stated above to give, to fulfill. For example, development inhibitor-releasing compounds are used which themselves None in the oxidized color developing agent coupling Provide dye. Furthermore, for example, development inhibitor-releasing compounds are used which the Release development inhibitors by an oxidative cleavage. Such compounds are described, for example, in US Pat 3,379,529, 3,043,690, 3,364,022, 3,297,445 and 3,287,129 wrote. Possibly. can when using development inhibitors releasing compounds Silver halide emulsions ver light-insensitive, such as Lipmann Emulsions, for the production of intermediate layers or cover layers used to be an undesirable migration of the development To prevent or control inhibitors, as for example from US-PS 3,892,572 is known.

The recording materials of the invention may further also colored couplers provide, for example such as they are used to produce integral masks for negative color images are used, and / or so-called competition coupler. The recording materials can finally z. B. also contain color image stabilizers. All these Additives are closer z. In the reference "Research Dis closure ", Vol. 176, Dec. 1978, Item 17643, Section VII.

The dye images can be further generated by methods or reinforced, which in combination with a Dye image-forming reducing agent, an oxidizing agent in the form of an inert transition metal ion complex and / or a Peroxidoxidationsmittels is used.  

The novel recording materials can, for. B. be designed in an advantageous manner so that they Generation of dye images by methods are suitable, such as they are described more fully, for example, in US Pat. No. 3,822,129, 3,834,907, 3,902,905, 3,847,619 and 3,904,413.

The recording materials of the invention may further correspond to the type of recording materials in which color fabric pictures by selective destruction of dyes or color Substance precursors are generated, for example the so-called silver-dye bleaching method, as it is closer described by A. Meyer in the journal "The Journal of Photographic Science, Vol. 13, 1965, pages 90-97.

In the production of color images from silver halide It is photographically containing photographic materials usual to remove the developed silver by bleaching. The removal of the developed silver can be achieved by introduction a bleach accelerator or a corresponding precursor compound in a developing solution or in a layer of Accelerate recording material. In some cases, the Amount of silver generated by development, be small in comparison to the amount of dye produced, in particular in the case of color image intensification methods, as described above, why the fading of the silver without significant visual Effect can be omitted. In other cases, in turn, the silver image and the dye image is used to to enhance the density produced by the silver image or to complete. In the case of dye-enhanced silver images it usually sneezed to be beneficial, a neutral one Dye or a combination of dyes, who together create a neutral picture. It is further possible, monochromatic or neutral dye images from only To produce dyes and the silver completely out of the picture generating recording materials by bleaching and fixing to remove.  

It is known that some photodetectors z. B. Semiconductors in video cameras detectable photo have electrical quantum yields similar to those of photo are superior to graphic silver halide recording materials. A study of the properties of conventional photographic images silver halide based drawing materials shows that this more on the binary, two-step nature of each silver halide grains is attributable to their low quantum sensitivity ness. This is discussed, for example, in a work by Shaw "Multilevel Grains and the Ideal Photographic Detector", published in the journal "Photographic Science and Engi neering ", Volume 16, No. 3, May / June 1972, pages 192-200 the two-stage nature of the silver halide grains is meant that a silver halide grain becomes fully developable once a latent image center has been formed on the silver halide grain is. The normal development is independent of that on the grain the amount of light hit, provided that the latent image generating Minimum amount of light has hit the grain. The silver halide grain produces exactly the same product in the development, whether it absorbs many photons and no matter if different latent image centers were generated upper if only the minimum number of photons were absorbed to a single image center produce.

In an exposure of a recording material according to the invention thus become tabular in and on the silver halide grains Form and high aspect ratio generated latent image centers. On some grains can only a latent image center be generated on others several. The number of generated However, latent image centers are related to the amount of ex panning radiation. Since the tabular silver halide grains can have a comparatively high diameter and there Their sensitivity-granularity ratio can be high in the special in the case of chemically and spectrally sensitized Silver bromide iodide, their sensitivity can be comparatively high his. As the number of latent image centers in or on each grain  directly related to the amount of exposed radiation, which has hit the grain, is the potential for a high detectable quantum yield, provided that this information is not lost during development.

Advantageously, each latent image center will be under Er increase its size, without the silver halide grain full constantly evolve. This can be done by interrupting the silver halo gene development at an earlier than normal stage follow in time before optimal development in case usual photographic applications has been achieved. Another possibility is a so-called. DIR coupler and to use a color developer compound. The at the clutch Released inhibitor compound can be used to to complete the development of the silver halide grains prevent. Advantageously, even inhibiting Ent Winder be used, d. H. Developers who have a development of silver halide grains, but the development itself before the silver halide grains fully develop have been. Preferred developers are self-inhibiting Developers containing p-phenylenediamines, as for example be described in more detail by Neuberger and coworkers in one Work with the headline "Anomalous Concentration Effect: An Inverse Relationship Between the Rate of Development and Developer Concentration of Some p-Phenylenediamines ", published in the journal "Photographic Science and Engineering", Volume 19, No. 6, November-December 1975, pages 327-332. At one under rupted development or development in the presence of a DIR Coupler can silver halide grains with a longer Ent winding induction period as adjacent, evolving Grains are completely excluded from development. The However, use of a self-inhibiting developer has the advantage that the development of a single silver halide grain is not inhibited until a certain development of Kornes is done. By an increase in the development of the latent  Image centers will produce a variety of silver spots. These Silver patches are of a size and number that is proportional the degree of exposure of each grain. Since the preferred ver self-inhibiting developers used color developing agents contain the oxidized developing compounds with a a dye-forming coupler to form a color React the fabric image. However, there is only a limited amount of silver halide amount is developed, is the amount of dye that produced in this way is also limited. A possibility, by which such limitations with respect to a maximum Dye density formation are eliminated, but in which the ratio from dye density to degree of exposure is maintained therein, a silver-catalyzed oxidation-reduction reaction to be carried out using a peroxide or a transition metal ion complex as the oxidant and a dye image-forming reducing agent, e.g. B. a color developer compound. In the cases where the silver halide grains produce latent image centers on the surface, The centers themselves can supply enough silver to match the color catalyze fabric image amplification reaction. Consequently, the Stage of increase of the latent image by development not absolutely necessary if advantageous. Preferably every visible silver in the photograph material remains after color imaging, by bleaching removed, as is common in the field of color photography.

The resulting photographic image is a dye image with a dot-shaped dye density, which is proportional to the exposure used amount of light is. The result is that the detectable quantum yield of the photographic recording materials is high. High photographic sensitivities are easily achievable, although oxidation-reduction reactions, such as described above, can contribute to increased graininess.  

The graininess can be determined by using a microcellular Carrier, as shown in more detail, for example in the PCT-Anm. WO 80/01614 described, reduce. The impression of graininess becomes not only by the size of the individual image dye clouds but also by the arbitrariness of their Placement. By applying the emulsions in a regular Arrangement of microcells using a corresponding Carrier and blur the generated dye in each mic cell, so that it becomes uniform, the perception of the Graininess be reduced.

Although the partial grain development with reference to the generation of dye images has been discussed, a Such partial grain development also in the production of Silver pictures done. In the development of producing a Silver image, the graininess of the silver image can be diminished, by interrupting the development before grains with latent Image centers have been fully developed. Because a bigger one Number of silver centers or silver spots by a partial Grain development can be produced as by a development of the entire grain, the perception of graininess can contribute of a given density. A corresponding Reduction of graininess can also be in the production of color images using incorporated couplers rich, by limiting the coupler concentration so, that the coupler is present in a concentration which is below the normally used with respect to silver halide stoichiometric Coupler concentration is. Although silver coating thicknesses in the photographic recording material must be higher in the beginning, to allow partial grain development to maximum Density levels compared to those of total grain development To achieve this, the silver halide that has not been developed is to be removed by fixing and recovered, which is why the total consumption of silver does not need to be increased.  

Partial grain development during production photo graphic silver images using recording materials with carriers having a microcellular structure it is possible to diminish the graininess of silver images, similar to the above in connection with the production of color images described. If, for example, one of the ver ver reversible silver halide emulsions in an array of micro housed cells of a carrier and after the imagewise Be partially developed, so will a variety of silver blotches in proportion to the radiation quanta, which in Be exposure to the material and proportional to Number of generated latent image centers generated. Although the Opacity of the silver stains is low compared to the deck force achieved through complete grain development, it can be done by unmixing undeveloped silver halagenide, rehalogenating the silver present in the microcells and subsequent physical development of the silver to a uniform layer of physical development nuclei in increase the microcells. As silver, physically on fine Germs is designed to have a much higher density than developed by chemical means silver, can thus be easily achieve a considerably higher maximum density. Furthermore The physically developed silver produces a uniform Density within each microcell. This leads to a Decrease in graininess, as an arbitrary silver density is replaced by the uniformity of the microcell pattern.

Are the tabular emulsions used in this invention Silver halide grains of a high aspect ratio in optimal Way, as described above, within a selected spectral sensitizes and increases the sensitivity of the emulsion within this spectral range with a spectral range compared to which the emulsion is a suspected natural Has sensitivity due to the halide composition, so It can be seen that a considerably larger Sensitive keitsdifferenz exists, as in the usual known  Emulsions can be observed. An inadequate separation of the Blue and green or red sensitivities of silver bromide and Silver bromide iodide emulsions have long been in the field the multicolor photography proved disadvantageous. The advantage Use of spectral sensitivity differences fiction according to usable silver bromide and silver bromoiodide emulsions will be described below using the example of a multi-color recording explained in more detail. In fact, the elevated spectral Sensitivity differences, the invention usable Have emulsions, not only for multicolor photography advantageous or on silver bromide and silver bromoiodide emulsions limited. Rather, the spectral sensitivity affects differences of the emulsions, for example, in the case of photo graphic recording materials with only one emulsion layer out. In fact, the advantages of increased spectral Sensitivity differences on a wide variety of applications take advantage of using emulsions of various kinds Halide composition of the photographic art ver used type. While, for example, silver chloride and silver Bromidiodidemulsionen known to be sufficiently low have natural blue sensitivity, so that they to Auf Drawing of green or red light in photographic multicolor Recording materials without protection from blue light exposure can be used in other cases but advantage be liable if the sensitivity differences between different which spectral ranges are increased. For example, a Silver chloride emulsion with tabular silver chloride grains a high aspect ratio to the infrared range the spectrum sensitized and imagewise in the spectral range the sensitization exposed, it may later in the presence be developed by light with a smaller increase in the Minimum density, due to the reduced sensitivity of Emulsions in the spectral areas, which are spectral Sensitization are free.  

In general, every known Recording material for the production of multi-color images with at least one silver halide emulsion layer according to the invention improve it by one of its described silver halide emulsions with tabular silver halide grains of high aspect ratio added or instead a usual layer used. The emulsions can be used for Production of color images by the additive multicolor process as well as for the production of color images after subtractive Color method can be used.

For the production of multi-color images after the additive More Color process can be an inventive, for the production a silver image suitable recording material, for example wise in combination with a filter arrangement with blue, green and red filter elements. In this case, a erfindungsge moderate recording material with a panchromatisch sensibili silver halide emulsion layer with tabular silver halide grains of a high aspect ratio image by exposed the additive primary filter assembly. After the ent winding of the recording material to produce a silver Image and viewing through the filter arrangement results multicolored picture. Such pictures are best passed through Look at projecting. As a result, either the Recording material and the filter assembly each one or both together a common transparent carrier.

Particular advantages also arise when using the described tabular silver halide grain emulsions a high aspect ratio for the production of photographic Multi-color recording materials for the production of multicolor images of combinations of subtractive primary image dyes. Such recording materials usually consist of a Carrier and typically at least one on the carrier  plotted triad of stacked silver halide emulsion layers for the separate recording of blue, green and red light in the form of yellow, purple or blue green dye images. A for making a multicolor Image suitable recording material according to the invention has thus at least one emulsion layer with tabular Silver halide grains of a high aspect ratio. When it has proven particularly advantageous for the production of Multi-color recording materials Silver bromide or silver bromide iodide emulsions containing tabular silver halide grains of a high aspect ratio. The following description refers therefore to certain preferred embodiments inventive multi-color recording materials under Use of silver bromide and silver bromoiodide emulsions are made. However, advantageous results can be obtained even if these emulsions are replaced by other silver halide emulsions containing tabular silver halide grains be replaced with a high aspect ratio.

According to the invention, in a color recording material, a minus blue sensitized silver bromide or silver bromoiodide emulsion having high aspect ratio tabular silver halide grains forms at least one of the emulsion layers for recording green or red light in a triad of blue, green and red Emulsion layers of a multi-color recording material is determined. The silver halide tabular grain emulsion is thereby advantageously arranged so as to have blue light impinge upon it during the exposure of the neutral light recording material of 5500 ° K in addition to the light to be recorded by the layer. The ratio of blue light to minus blue light striking the layer can be expressed in terms of the Δ log E value, where:

Δ log E = log E _T - log E _B

where:
log E _{T is} the logarithm of green or red light exposure to record the emulsion layer and
log E _{B is} the logarithm of the simultaneous exposure to blue light impinging on the emulsion layer.

In all cases, unless otherwise stated, is following E given in lux-seconds.

According to the invention, Δ log E may be less than 0.7, preferably Less than 0.3, while achieving advantageous re gave a multicolored object. This is in terms of the high ratio of grains with a mean diameter greater than 0.7 microns in the tabular emulsions Silver halide grains surprising. Used to make a Recording material, a comparable silver halide emulsion with non-tabular silver halide grains or tabular Silver halide grains with low aspect ratio at the same Halide composition and same mean grain diameter instead of the silver bromide or silver bromide iodide emulsion high aspect ratio tabular silver halide grains used, so occurs a stronger and generally unacceptable bare color distortion on. It is known that a Farbver falsification by green or red sensitized silver bromide or silver bromoiodide emulsions by reducing the mean Can reduce grain diameter, but this leads simultaneously to a limitation of the maximum achievable photographic Sensitivity. The invention not only allows an advantage weak separation of the blue and minus blue sensitivities, but achieves this without restriction of the achievable minus blue sensitivities.  

According to a particularly advantageous embodiment of the invention At least the minus-blue recording emulsions exist layers of a triad of blue, green and red recordings Emulsion layers of silver bromide or silver bromide iodide emulsion layers. As beneficial it has further proved when the blue-recording emulsion layer of the triad also from a tabular silver halide emulsion layer grains of a high aspect ratio. According to one another particularly advantageous embodiment of the invention have the tabular grains present in each of the emulsion layers a triad are present, a thickness of less than 0.3 microns and a mean grain diameter of at least 1.0 micrometer, preferably at least 2.0 microns. Show in an advantageous manner the multi-color recording materials of the invention further an ISO sensitivity index of at least 180.

The multi-color recording materials according to the invention need no yellow filter layer between the light source and the green ones and / or red tabular silver halide emulsion layers grains of high aspect ratio to protect these layers to show before a blue light. Is still a yellow Filter layer before, so the density of the layer can be reduced be such that their density is lower than that of the past used yellow filter layers around the red or green Drawing emulsion layers of the recording material, the used to daylight exposures, before exposure to protect from blue light.

According to another particularly advantageous embodiment of the Invention is located between the green and / or rotaufzeichnende Emulsion layers of the triad and the light source do not turn blue drawing emulsion layer. As a result, the recording material practically free of blue absorbing material between the green and / or red recording emulsion layers and the incident radiation used for exposure.  

In a multi-color recording material according to the invention, in the only one of the green- or red-recording emulsions layers or both of a silver halide emulsion high aspect ratio tabular silver halide grains should exist, the other emulsion layers of a usual for photographic multi-color recording materials known type exist. This means that the other emulsions layers not composed of silver halide emulsion layers high aspect ratio tabular silver halide grains consist of emulsions can be produced, as example Wise described in the reference "Research Disclosure, Vol. 176, Dec. 1978, Item 17643, Section I.

According to a further advantageous embodiment of the invention All emulsion layers contain silver bromide or silver bromidiodidkörner. It has proved to be particularly advantageous when at least one green-recording emulsion layer and at least one red-recording emulsion layer of a silver halide emulsion with tabular silver halide grains of high aspect ratio is generated. Lying in the recording material more than one emulsion layer for recording in green and / or red area of the spectrum, so it has proved to be particularly advantageous if at least the sensation Licher emulsion layer of an emulsion layer with blackboard shaped silver halide grains is produced. According to another advantageous embodiment of the invention, all emulsions exist layers of the recording material, namely the blue, green and rotaufzeichnenden emulsion layers of emulsion layers with high aspect ratio tabular silver halide grains.  

The invention enables the production of photographic More Color-recording materials in which the sensitivity and the contrast of blue, green, and red emulsions layers can vary greatly. The relative blue insensitivity sensitivity of the green or red spectrally sensitized silver bromide or silver bromide iodide emulsion layers with blackboard shaped silver halide grains of high aspect ratio allows the green and / or red-recording emulsions layers in various positions of a multicolor independent of the others Emulsion layers and without the use of usual caution measures to protect their exposure to blue light.

Inventive multicolor recording materials are suitable especially for natural color reproduction during exposure with daylight. Photographic recording materials of this Type are characterized in that they are blue, green and red Color records of substantially matched contrast and provide limited sensitivity change when they do a source of light of 5500 ° K (daylight). The Means "substantially matched contrast" in that the blue, green and red records in contrast by less than 20, preferably less than 10%, based on distinguish the contrast of the blue record. The limited Sensitivity change of blue, green and red records can be expressed as a sensitivity change (Δ log E) less than 0.3 log E, with the sensitivity change the greater of the differences between the sensitivity of the green or red record and the sensitivity of the blue Record is. The contrast and logarithmic sensitivity sizes necessary for the determination of these relationships of the recording material according to the invention, can be by determining that a photographic recording material at a color temperature of 5500 ° K by a spectral Non-selective step wedge, for example, a test object  Carbon exposed and the recording material preferably developed under the recommended development conditions. By Measurement of the blue, green and red transmission densities of the Recording material for blue light of a wavelength of 435.8 nm, green light of a wavelength of 546.1 nm and red Light of a wavelength of 643.8 nm, as described in more detail in US Pat the American standard PH2.1-1952, publisher: American National Standards Institute (AINSI) 1430 Broadway, New York, N.Y. 10018, blue, green and red characteristic curves for the Recording material to be recorded. Indicates the recording Material is a reflective carrier instead of a transparent one Carrier on, so instead of the transmission density reflections densities are measured. From the blue, green and red charak teristics curves can be adjusted to the sensitivity and contrast according to the Determine the specialist's usual method. That in the individual case ange applied sensitivity and contrast measurement is of little Meaning, provided that the individual blue, green and red recorded in an identical manner. Of the American National Standards Institute (AINSI) is a variety of Standard Sensitometer Measurement Methods for Photographic Read More color recording materials have been published. The following Measurement method: American Standard PH2.21-1979, PH2.47-1979 and PH2.27-979 are representative.

The photographic multi-color recording of the present invention materials that deliver particularly lifelike color reproduction, when exposed to sunlight, offer over usual corresponding to known photographic recording materials Type significant advantages. In the inventive recording materials, the limited blue sensitivity of the spectral green and red sensitized tabular silver bromide and Take advantage of silver bromide iodide emulsion layers to obtain the Blue sensitivity of the blue recording emulsion layer and the blue sensitivity of the minus-blue recording emulsions separate layers. Depending on the specific application  may be the use of tabular silver halide grains in the green and red recording emulsion layers to a desirable large separation in the blue response of the lead blue and minus blue recording emulsion layers.

In some cases it may be desirable to have the blue sensation separations of blue and minus blue recordings To further increase emulsion layers by using conventional Blue sensitivity separation techniques to reduce blue sensitivity separations due to the presence of the tabular Silver halide grains of high aspect ratio can be achieved to complete. Is located for example in a photographic Recording material the most sensitive green-recording emulsions layer closest to the light source and is the most sensitive blue-recording emulsion layer from the light source farthest removed, the separation of the blue sensitivities of blue- and green-recording emulsion layers, albeit one Difference of a full order of magnitude (1.0 log E), when the emulsions are applied separately to a support and effectively diminished by the layer arrangement, since the green-recording emulsion layer all the blue light during exposure, the green recording layer and other overlying layers, however, a part of the blue Light can absorb or reflect light before it's blue recording emulsion layer achieved. In such a case may be the use of a higher iodide content in the blue recording emulsion layer can be used to the blackboard shaped silver halide grains in increasing the blue sensitivity separation of the blue and minus blue-recording emulsions support layers. There is a blue recording Emulsion layer of the light source closer than the minus-blue drawing emulsion layer, so can one between the blue and housed in the minus blue recording emulsion layer yellow filter material of limited density can be used to to increase the blue and minus blue separation. In no case  however, it is necessary to use one of the usual ones Sensitivity separation techniques to the extent to make that themselves a difference in the blue Sensitivity separation of an order of magnitude leads or one Approach to this, as previously required. The application However, such techniques can not be ruled out if a pronounced blue and minus blue sensitivity separation for a particular application is desired. The present The invention thus enables the production of multi-color recording materials for natural color reproduction when exposed to daylight conditions, with a larger Freedom in the construction of the recording material with respect to the Layer arrangement is achieved, as it was previously possible.

Advantageously, an inventive multicolour Drawing material also in for color recording materials usually from so-called color-forming layer units build his. Thus, the recording material according to the invention For example, three superimposed color-forming layers each having at least one silver halide emulsion layer, the light of a different Third of the spectrum is able to record and so a komple provide a subtractive primary dye image. This means, that in the case of such a recording material blue, green and red-recording color-forming layer units are the yellow, purple or cyan dye images too deliver wealth. Need in the color-forming layer units Dye-providing compounds should not be present. You can from development solutions used in color development be supplied. Are image dyes supplying compounds in the recording material, they may be in emulsion layers itself or be housed in layers that arranged so are that the color former with oxidized developing agent or an electron transfer agent from an adjacent one Emulsion layer of the same color-forming layer unit in Can contact.  

To a migration of oxidized developing agent or Electron transfer agent between color-forming layers to prevent units from degrading color reproduction can in the usual manner known. Capture compounds be used. These scavenging compounds can be found in the Emulsion layers are housed themselves, as example example, from US-PS 2,937,086 is known or in intermediate layers between adjacent color-forming layer units, as described, for example, in US Pat. No. 2,336,327.

Each of the color-forming layer units can be one, two, have three or more emulsion layers that are in differ from each other in their photographic sensitivity. If the desired layer arrangement does not permit several emulsion layers, distinguished by their sensitivity different from each other, in a color-forming layers can be arranged, so can several, usually two or three blue, green and / or red color forming Layer units in a photographic recording material to be available.

According to the invention, there is at least one green or red recording emulsion layer of a recording according to the invention materials from a layer of tabular silver halide grains of a high aspect ratio, in particular one Silver bromide or silver bromide iodide emulsion layer, such is arranged to have an increased proportion of the blue light in the imagewise exposure of the recording material takes. The increased proportion of blue light that the emulsions layer with the tabular silver halide grains of a high Aspect ratio can be reached from a diminished Blue light absorption by a yellow lying over the layer filter layer yielded or preferably by complete Elimination of the yellow filter layers. The increased proportion of blue light containing the silver halide emulsion layer with the  obtained tabular silver halide grains may also resulting from a rearrangement of the color-forming layer unit, in which the layer is located closer to the light source. So can for example, the green and rotaufzeichnenden color-forming Layer units with green and red recording emulsions layers with high aspect ratio silver halide grains be arranged closer to the light source than a blue recording color-forming layer unit.

Apart from the requirements of claim 1, can a fiction According to a multi-color recording material in its construction one of customary known color photographic recording materials correspond. For example, the layer arrangement of a correspond to the 6 possible layer arrangements, from the Gorokhovskii's book "Spectral Studies of the Photographic Process ", publisher Focal Press, New York, page 211, Table 27a are known.

In general, it is possible in the production of a usual Silver halide based multi-color recording material, one or more several of the described silver halide emulsion layers tabular silver halide grains opposite to the minus blue are sensitized to the range of the spectrum, add and so on to arrange that on them the radiation used for the exposure rather than the other layers. In most cases However, it is particularly advantageous to have one or more of the minuses blue recording layers with the tabular silver halide grains with a high aspect ratio instead of the usual minus blue recording layers, if necessary with a modification of the layers arrangement.  

For example, a recording material according to the invention for the production of color images may have one of the following layers:

in which mean:
B, G and R denote blue, green and red recording color forming layer units of conventional type;
T means that the emulsion layer or layers have been prepared from silver bromide or silver bromoiodide emulsions with high aspect ratio tabular silver halide grains as described;
HE means that the color forming layer unit has a higher photographic speed than at least one other color forming layer unit which records light of the same third of the spectrum in the same layer arrangement;
WE means that the color forming layer unit concerned has a lower sensitivity than at least one other color forming layer unit which records light of the same third of the spectrum in the same layer arrangement and
ZWS denotes an interlayer with a scavenger compound, but which is free or substantially free of yellow filter fabrics.

Any higher sensitive or less sensitive color forming layer unit may be in their photographic Sensitivity of another color-forming layer unit, the light of the same third of the spectrum records, distinguish as a consequence of their position in the layer arrangement, their own sensitivity properties or one of their own Combination of these.  

In the layer arrangements I-IX, the position of the carrier is not shown. According to the practice, the wearer is located farthest from the light source in most cases, d. H. below the layers shown. Is the carrier colored go and permeable to radiation, d. H. transparent, he can too arranged between the light source and the specified layers his. This means that the substrate between the light source and each color-forming layer unit can be arranged which is intended for recording light for which the wearer is permeable.

In the case of the layer arrangement I, there is no yellow filter material in front. In for recording materials with a yellow filter layer usual practice is the blue-recording color-forming Layer unit, however, closest to the light source. in case of a Recording material of the type described can in the simplest Trap each color forming layer unit from a single silver consist of halide emulsion layer. Each of the color-forming layers However, units can also have 2, 3 or even more different silver having halide emulsion layers. Becomes a triad of Emulsion layers, one of highest sensitivity of each the color-forming layer units, compared, so is their contrast preferably substantially matched to each other and the photo graphical sensitivity of green and red recording emulsions layers differs from the sensitivity of the blue-recording emulsion layer by less than 0.3 log E. If there are two, three or more emulsion layers that are in each color forming layer unit in its sensitivity differ from each other, so are preferably two, three or more triads of emulsion layers in the layers order I with the specified contrast and sensitivity relationship. The absence of a yellow filter material below half of the blue-recording color-forming unit increases photographic sensitivity of this unit.  

In the case of layer arrangement I, it is not necessary that the intermediate layers are free or practically free of one yellow filter material are. For example, less than usual concentrations of yellow filter material between the housed blue and green recording color forming units without departing from the teachings of the invention. Furthermore, the intermediate layer, the green and rotauf separating color-forming layer unit from each other, up to usual amounts of yellow filter material, without to deviate from the teachings of the invention. In the case in which usual concentrations of yellow filter material are used, the red recording color forming unit is not limited to the use of tabular silver bromide or silver Bromidiodidkörnern, as described above, but rather can have any usual shape taking into account the specified Contrast and sensitivity considerations.

In order to avoid unnecessary repetitions, the following should in the discussion of layer arrangements II-IX only such Characteristics are discussed by the characteristics of the layers arrangement I differ.

In the case of the layer arrangement II are instead of higher em sensitive and less sensitive blue, red or green recording emulsion layers in the same color-forming Layer unit two separate blue, green and red recording provided color forming layer units. Only the Emul layer or the emulsion layers of the more sensitive ones color-forming units contain tabular silver bromide or silver bromoiodide grains of the type described. The less more sensitive green and red color-forming layers units are due to their lower sensitivities like also due to the overlying more sensitive blue record protected the layer unit from blue light exposure, without a yellow filter material is used. The usage  of silver bromide or silver bromoiodide emulsions with silver halide grains of high aspect ratio in the emulsion layer or the emulsion layers of the less sensitive ones green and / or red color forming units Of course not excluded. The fact that the sensation more intense red-recording color-forming layer unit over the less sensitive green-forming color-forming layers unit is arranged, can be an increased sensitivity reach, as for example from US-PS 4,184,876 and DE-OS 27 04 797, 26 22 923, 26 22 924 and 27 04 826 known is.

The layer arrangement III differs from the layers I arrangement in that the blue-recording color-forming layers unit is furthest away from the light source. The green recording color forming layer unit is located closest to the light source and the red recording color forming Layer unit is located between the green and the blue recording layer unit. This arrangement has proven to be particularly advantageous for producing sharp, high-quality Multi-color images proved. The green recording layer unit, the most important visual contribution to color image production As a result, they can be closest to the light source lies, produce a very sharp image, since none above the green layers are arranged on the recording layer, the can lead to a light scattering. The rotaufzeichende color forming layer unit, the next most important visual Contributing to color image making supplies light that receives only by the green-recording color-forming layer unit and as a result has not yet recorded in blue the color-forming layer unit has been scattered. Although the blue recording color forming layer unit in comparison is disadvantaged to the layer arrangement I, the sharpness loss increases not the advantages of having the green and red up drawing color-forming layer units are generated since  the blue recording color forming layer unit at by far the lowest visual contribution in image production supplies.

The layer arrangement IV differs from the layers Arrangement III essentially in that they green and red recording color-forming layer units with separated higher sensitive and less sensitive emulsion layers with tabular silver halide grains of a high aspect contains ratio. The layer arrangement V differs from the layer arrangement IV in that a further blue-recording color-forming layer unit over the less more sensitive green, red and blue color forming Layer units is arranged. The more delicate blue drawing color-forming layer unit contains a Silver bromide or silver bromide iodide emulsion layer with blackboard shaped silver halide grains of high aspect ratio, as described above. The more sensitive blue color forming layer unit absorbs blue light in this case and reduces the amount of blue light that is on the less sensitive green and red imaging image-forming layers units impinges.

In a modified form, the less sensitive green and red recording color forming layer units none Emulsion layers with tabular silver halide grains of a high aspect ratio.

The layer arrangement VI differs from the layers Arrangement IV in the arrangement of a blue recording color forming layer unit with tabular silver halide grains between the green and red color forming Layer units and the position of the exposure ver used light source. As already stated, the blue light can recording color-forming layer unit of one or more blue-recording emulsion layers with tabular silver halide grains and in the case in which several blue Light-recording emulsion layers are present, can  they differ in their sensitivity from each other. To the less favorable position to compensate for the red otherwise occupy drawing color-forming layer units In addition, the layer arrangement VI differs further of the layer arrangement IV in that a second more sensitive provided red light recording color-forming layer unit is that color-forming between the blue light recording Layer unit with tabular silver halide grains and the is arranged for exposure used light source. In terms of to the more favorable position, which the second more sensitive red light recording color forming layer unit with the tabular grains, it is more sensitive than the first more sensitive red-recording layer unit when the two more sensitive red-recording layer units same emulsions are produced. It should be noted, of course, that the first and the second more sensitive red-recording color if it is, tabular grain forming layer unit desires to be generated by the same or different emulsions can, and that their relative sensitivities after usual known methods can be adjusted. Instead of using of two comparatively sensitive red light recording Layer units, as shown, may be the second sensitive one red light recording layer unit possibly also by a second sensitive green light recording color-forming Layer unit to be replaced. The layer arrangement VII can However, the layer arrangement VI correspond, differs characterized by the layer arrangement VI that both a second more sensitive red-recording color-forming layer unit with tabular silver halide grains, as well as a second more sensitive green-forming color-forming layers unit with tabular grains between for exposure used light source and the blue light recording color forming tabular silver halide grain layer unit.

The layer arrangements VIII and IX are usual layer arrangements, in which the intermediate layers under half of the layers that record blue light, a yellow filter have material. In the case of these layer arrangements, however,  there is a silver halide emulsion layer with blackboard shaped silver halide grains of a high aspect ratio closest to the light source used for exposure. The to Preparation of these layers used emulsions with panel silver bromide iodide grains can be used to record red light, as indicated, against the record of green Light or be sensitized in pairs of layers to red or to record the green light.

Apart from the example illustrated layer arrangements I-IX many other advantageous layer arrangements are possible. In each of the different layer arrangements, for example example corresponding green and red color-forming Layer units are exchanged, d. H. the more sensitive red- and green-recording color-forming layer units can change their position in the different layer arrangements, additionally or alternatively, the less sensitive green and red recording color forming layer units their position can change.  

Although photographic emulsions used for the preparation of multicolor images are intended, which consist of a combination constructed of subtractive primary dyes, more normal wise in the form of a plurality of superimposed layers used with incorporated dye-forming compounds be supplied, for example with incorporated dyes Couplers, this is not required in any way. Much more it is also possible to have three color-forming components, more normal referred to as "packs", each containing a silver halide emulsion for recording light of one-third of the view Baren spectrum and a color coupler, leading to the formation of a complementary subtractive primary dye is capable of contained in a single layer of a photographic Recording material for producing a multicolored image accommodate. Recording material of this type, d. H. suction. For example, multicolor mixed package recording materials from US Pat. Nos. 2,698,794 and 2,843,489.

As already stated, it is the comparatively large separation Blue and minus blue sensitivities of green and red drawing color-forming layer units with silver bromide or silver bromide iodide emulsion layers with tabular silver halide grains which reduce or eliminate yellow filter material and / or the use of new layers arrangements.

One method that can be used to obtain a quantitative measure of the relative response of green and red recording color forming layer units to blue light in more colored photographic materials is to expose a portion of the multi-color photographic material by a step wedge with a neutral light emitting light source, ie light of 5500 ° K and then develop the section. A second section is exposed in the same way with the exception, however, that between the recording material and the light source a Wratten filter No. 98 is arranged, which passes only light of wavelengths between 400 and 490 nm. The section is then developed in the same way. Using blue, green and red transmittance densities as determined by American Standard PH2.1-1952 as described above, three dye characteristic curves can be recorded for each section. The differences Δ u. Δ 'in the blue sensitivity of the blue recording color forming layer unit (s) and the blue sensitivity of the green or red recording color forming layer unit (s) can be determined from the following relationship:

Δ = (B _E98 - G _W98 ) - (B _N - G _N ) or (A)

Δ '= (B _W98 - R _W98 ) - (B _N - R _N ) (B)

in which mean:
B _W98 the blue sensitivity of the blue-recording color-forming layer unit (s) exposed by the Wratten filter No. 98;
G _W98 the blue sensitivity of the green recording color-forming layer unit (s) exposed by the Wratten filter No. 98;
R _W98 the blue sensitivity of the red-recording color-forming layer unit (s) exposed by the Wratten filter No. 98;
B _{N is} the blue sensitivity of the blue recording color-forming layer unit (s) exposed to neutral (5500 ° K) light;
G _{n is} the green sensitivity of the green recording color-forming layer unit (s) exposed to neutral light (5500 ° K) and
R _{N is} the red sensitivity of the red-recording color-forming layer unit (s) exposed to neutral light (5500 ° K).

The above description writes blue, green and red densities the blue, green and red color forming layers units and ignores an unwanted spectral Ab absorption by the yellow, purple and blue-green dyes. Such unwanted spectral absorption is not of of sufficient magnitude to the results achieved for the purpose required here.

The multi-color recording materials according to the invention have in the absence of any yellow filter material, a blue sensitivity due to the blue-recording color-forming layers unit at least 6 times, preferably 8 times and optimally at least 10 times the blue sensation the green and / or red color forming Layer units with tabular silver halide emulsions Corresponds to high aspect ratio silver halide grains.

For the sake of comparison, an example is to illustrate that a conventional multicolor photographic material without a yellow filter layer has a blue sensitivity difference between the blue recording color forming layer unit and the green recording color forming layer unit less than 4 times (0.55 log E) compared to almost 10 times (0.95 log E) in the case of a comparable multi-color recording material according to the invention. This comparison illustrates the advantageous reduction in the blue sensitivity of green-recording color-forming layer units which can be achieved according to the invention by using silver halide or silver bromoiodide emulsions with tabular silver halide grains having a high aspect ratio. Another measure of the strong separation of the blue and minus blue sensitivities of a multi-color photographic material of the invention is to compare the green sensitivity of a green recording color forming layer unit or the red sensitivity of a red recording color forming layer unit with its blue sensitivity. For this purpose, the same exposure and development methods as described above, be applied, except that instead of the exposure to neutral light, a minus-blue clearing by interposition of a Wratten filter No. 9, which passes only light beyond 490 nm. The quantitative differences Δ "and Δ '''that can be determined are:

Δ "= G _W9 - G _W98 or (C)

Δ '''= R _W9 - R _W98 (D)

wherein
G _W98 and R _{W98 have} the stated value and furthermore mean:
G _{W9 is} the green sensitivity of the green recording color-forming layer unit (s) exposed by the Wratten filter No. 9 and FIG
R _{W9 is} the red sensitivity of the red-recording color-forming layer unit (s) exposed by the Wratten No. 9 filter. Again, the undesirable spectral absorption by the dyes is ignored because they are relatively insignificant.

Red and green color-forming layered units with tabular silver bromide or silver bromide iodide emulsions layers, as described above, have a difference between their sensitivity in the blue region of the spectrum and their Sensitivity in the part of the spectrum that is opposite to them are spectrally sensitized (i.e., a difference in their blue color). and minus blue sensitivities) of at least 10 times (1.0 log E), preferably at least 20 times (1.3 log E) on. For example, the difference may be greater than that 20 times (1.34 log E), while in the case of a comparable conventional photographic multi-color recording material without Yellow filter material the difference less than 10 times (0.95 log E) is located.

Comparing the quantitative relationships A to B and C to D in the case of a single-layer arrangement are the results not identical, even if not the green and identical to red-recording color-forming layer units are (except their wavelength of spectral sensitization). The reason for this is that in most cases the red-recording color-forming layer unit (s) light that hits the corresponding green-recording color-forming Layer unit (s) has already passed. Will one, however second layer assembly made identical to the first is, with the exception that the corresponding green and red recording color-forming layer units with respect to their Position were changed, then the rotaufzeichnende color-forming layer unit (s) of the second layer arrangement provide virtually identical values for relationships B and D, which the green recording color forming layer unit of first layer arrangement for the relationship A and C supplies. In short, the choice of green spectral sensitization In contrast to red spectral sensitization, this affects the values not obtained by the above quantitative comparison essential. As a result, it is common practice, not between green and red sensitivities compared to blue ones  Sensitivity but rather to the Green and red sensitivities as the minus blue sensitivity To refer to.  

The following examples are intended to illustrate the invention in more detail. By "percent" is always meant "wt .-%", if nothing another is indicated. The letter "M" means "molar". Provided Unless otherwise stated, aqueous solutions were used.

Examples showing the sensitivity-granularity ratio illustrate

First, a series of silver bromoiodide emulsions of produced various aspect ratios. In each of the following examples were the contents of for the production of the Emulsions vigorously used reaction vessels during Ein stirring the silver and halide salts. The characteristics the emulsions produced are shown in Table VI below following the description of the preparation of the emulsion 7 compiled.  

example 1 A. Emulsion Preparation and Sensitization Emulsion 1 (according to the invention)

To 5.5 liters of 1.5% gelatin solution with 0.17 M potassium bromide at a temperature of 80 ° C were stirred, after Double inlet process within a period of 2 minutes a 2.2 M potassium bromide and a 2.0 M silver nitrate solution given, with a pBr value of 0.8 was maintained. (This accounted for 0.56% of the total silver nitrate used consumed). The feed of the bromide solution was then stopped, while running silver nitrate solution for 3 minutes was (where 5.52% of the total silver nitrate ver were needed). The bromide and silver nitrate solutions were then run concurrently while maintaining a pBr Value of 1.0 accelerates (2.2 times faster at the end than at Beginning) over 13 minutes (wherein 34.8% of the total silver nitrate were consumed). The feed of the bromide solution was interrupted, whereupon for 1.7 minutes silver nitrate solution (corresponding to a consumption of 6,44% of the total silver nitrate used). A 1.8 M potassium bromide solution, which was further 0.24 M in terms of potassium iodide with the silver nitrate solution for 15.5 minutes after the double Enema process speeds up (1.6 times faster at the end than at Beginning), with 45.9% of the total used Silver nitrates were consumed, and where the pBr value was kept at 1.6. The feed of both solutions then became interrupted for 5 minutes using 1.5 g Sodium thiocyanate per mole of silver was digested. thereupon according to the double-inlet method, a 0.18 M potassium iodide solution and the silver nitrate solution at the same speed added until a pBr of 2.9 had been reached (ent speaking a 6.8% consumption of the total used  Silver nitrate. In total, about 11 moles of silver salt used. The resulting emulsion was then cooled to 30 ° C and according to the coagulation known from US Pat. No. 2,614,929 washed procedure. The emulsion was then at 40 ° C per mole Silver 464 mg anhydro-5-chloro-9-ethyl-5'-phenyl-3 '- (3-sulfo butyl) -3- (3-sulfopropyl) oxacarbocyanine hydroxide, sodium salt added as a green spectral sensitizer. Of Further, the pAg value was sustained after a 20 minute period Holding period set to 8.4. Finally, the emulsion 3.5 mg of sodium thiosulfate pentahydrate per mole of silver and 1.5 mg potassium tetrachloroaurate added per mole of silver. The pAg was adjusted to 8.1 and the emulsion became 5 Heated to 65 ° C for minutes. The pAg value adjustment was made with a potassium bromide solution.

Emulsion 2 (according to invention)

To 5.5 liters of a 1.5% gelatin solution containing 0.17M Potassium bromide of 80 ° C and a pH of 5.9 were below Stir a 2.1 M potassium bromide after the double-jet process solution and a 2.0 M silver nitrate solution over a period of time of 2 minutes, with a pBr of 0.8 was obtained (with consumption of 0.53% of the total ver used silver nitrates). The feed of the bromide solution was under broken and the feed of silver nitrate solution still 4.6 minutes long continued, such that 8.6% the total amount of silver nitrate used was consumed. Thereafter, the bromide and silver nitrate solutions became again run simultaneously for 13.3 minutes, with a pBr value of 1.2 was maintained and the feed was accelerated (2.5 times faster than at the beginning), with consumption of 43.6% of the Total consumed silver nitrate. The feed of the bromide solution was then interrupted, whereupon for a minute silver nitrate solution was supplied (with consumption of 4.7% of the total used silver nitrate).  

A 2.0 M potassium bromide solution containing potassium iodide and with respect to potassium iodide was 0.30 M, after double Run-in procedure for 13 minutes with the silver nitrate solution accelerated added (1.5 times faster at the end of the addition) under Maintaining a pBr of 1.7 and below consumption of 35.9% of the total silver nitrate used. To the emulsion 1.5 g of sodium thiocyanate were then added per mole of silver, after which the emulsion was stored for 25 minutes. Then were according to the double-inlet method, a 0.35 M potassium iodide solution and further silver nitrate solution at a constant rate, for about 5 minutes until a pBr of 3.0 is reached (with consumption of about 6.6% of the total ver used silver nitrates). The total silver nitrate consumption was about 11 moles. Then a solution of 350 g became more phthalated Gelatin as described in US Pat. Nos. 2,614,928 and 2,614,929, added in 1.2 liters of water, whereupon the emulsion at 30 ° C. cooled and according to the known from US-PS 2,614,929 coagulation method was washed. The emulsion then became optimally spectrally and chemically sensitized, as in the preparation of the emulsion 1 described.

Emulsion 3 (according to the invention)

To 30.0 liters of 0.8% gelatin solution with 0.10 M potassium bromide were stirred at a temperature of 75 ° C with stirring the double-inlet process, a 1.2 M potassium bromide solution and a 1.2 M silver nitrate solution over a period of 5 minutes added while maintaining a pBr of 1.0 (corresponding to a 2.1% consumption of the total silver nitrate used). Then, 5.0 liters of a 17.6% solution of phthalated Gelatin was added, whereupon the emulsion kept for 1 minute has been. Then silver nitrate solution was run into the emulsion left until a pBr of 1.35 was reached  Consumption of 5.24% of the total silver nitrate used. Now, according to the double-inlet method, a 1.06 M Potassium bromide solution, further with respect to potassium iodide 0.14 M, and added more silver nitrate solution added (2 times faster at the end) with consumption of 92.7% of the total silver nitrate used, with a pBr of 1.35 was maintained. In total, about 20 moles of silver nitrate consumed. The emulsion was cooled to 35 ° C, after the Coagulation method washed and, as in the preparation of Emulsion 1 described optimally spectrally and chemically sensitized.

Emulsion 4 (according to invention)

To 4.5 liters of a 1.5% gelatin solution containing of 0.17M potassium bromide at 55 ° C and a pH of 5.6 with stirring according to the double-inlet method, a 1.8 M potassium bromide solution and a 2.0 M silver nitrate solution with constant Speed over a period of 1 minute with a pBr Value of 0.8 added (corresponding to a consumption of 0.7% Silver nitrate based on the total amount used). The Bromide, silver nitrate and a 0.26 M potassium iodide solution then simultaneously at constant speed over time allowed to run for 7 minutes, with a pBr of 0.8 was maintained and 4.8% of the total silver used Nitrate were consumed. The triple feed was then over continued for a further period of 37 minutes, taking a pBr of 0.8 was maintained, the feed rate but increased (4 times in relation to the beginning speed) corresponding to a consumption of 94.5% silver nitrate, based on the total amount of silver nitrate used. In total, about 5 moles of silver nitrate were used. The Emulsion was then cooled to 35 ° C followed by 1 liter of water was added with a content of 200 g of phthalated gelatin. The emulsion was then washed by the coagulation method. Subsequently, the emulsion was optimally spectrally and chemically  sensitized as described in the preparation of the emulsion 1.

Emulsion 5 (according to the prior art)

The emulsion was prepared by the method known from US Pat. No. 4,184,877 Process produced.

To a 5% solution of gelatin in 17.5 liters of water 65 ° C with stirring by the double-inlet method a 4.7 M ammonium iodide solution and a 4.7 M silver nitrate solution at a constant speed over a period of 3 minutes added, maintaining a pI of 2.1 (Consuming about 22% of silver nitrate at the the production of the germs was used). The feed rate The speed of the two solutions was then adjusted so that unge about 78% of the total silver nitrate used for germination used within a period of 15 minutes ver was needed. The feed of the ammonium iodide solution then became interrupted and the feed of the silver nitrate solution up to a pI value of 5.0 continued. In total, about 56 moles of silver nitrate used for the production of the germs. The emulsion was on Cooled to 30 ° C and as seed emulsion, as in the following be closer written, used. The mean grain diameter of the germs was 0.24 microns.

15.0 liters of a 5% gelatin solution containing 4.1 moles of 0.24 μm AgI emulsion as described above was added Heated to 65 ° C. A 4.7 M ammonium bromide solution and a 4.7 M Silver nitrate solution was with the double-inlet method with same speed over a period of 7.1 minutes added while maintaining a pBr of 4.7 (under a consumption of 40.2% of the total for precipitation of the germs required silver nitrate). Subsequently, more Ammonium bromide solution alone, until pBr was reached at about 0.9, whereupon the feed was interrupted  has been. Now, 2.7 liters of a 11.7 M ammonium hydroxide solution, whereupon the emulsion stands for 10 minutes was left. The pH was adjusted to 5.0 with sulfuric acid adjusted, which again after the double-inlet method Ammonium bromide solution and silver nitrate solution for 14 minutes were added while maintaining a pBr of about 0.9 and a 56.8% Consumption of the total silver nitrate used. The pBr value was then adjusted to 3.3 and the emulsion was at 30 ° C cooled. In total, about 87 moles of silver nitrate were used applies. Now, a solution with 900 g of phthalated gelatin followed by the emulsion according to the coagulation method was washed.

The pAg of the emulsion was then adjusted to 8.8, whereupon the emulsion 4.2 mg of sodium thiosulfate pentahydrate and 0.6 mg Potassium tetrachloroaurate each per mole of Ag were added. The emulsion was then heated to 80 ° C (16 minutes) and then cooled to 40 ° C, whereupon 387 mg of the green spectral sensitizing dye anhydro-5-chloro-9-ethyl-5'- phenyl-3 '- (3-sulfobutyl) -3- (3-sulfopropyl) -oxacarbocyanine hydroxide, sodium salt per mole of silver were added. thereupon the emulsion was kept for a further 10 minutes. The chemical and the spectral sensitization were with respect to ver used sensitizers optimally.

Emulsion 6 (according to the prior art)

It became an emulsion of the type known from US Pat. No. 3,320,069 manufactured.

To 42.0 liters of a solution of 1.25% phthalated gelatin, with respect to potassium bromide 0.050 molar, with respect to potassium iodide 0.012 molar and with respect to potassium thiocyanate was 0.051 molar, with a temperature of 68 ° C, were after the double-inlet method added with stirring at the same feed rates:  

A 1.32 M potassium bromide solution containing potassium iodide 0.11 molar and a 1.43 M silver nitrate solution. The feed took place for about 40 minutes. In the precipitation 21 moles Consumed silver nitrate. The emulsion was then lowered to 35 ° C cools and after the coagulation method, as in the US-PS 2 614 928, washed.

The pAg of the emulsion was adjusted to 8.1, whereupon 5.0 mg of sodium thiosulfate pentahydrate and 2.0 mg of the emulsion Potassium tetrachloroaurate per mole of silver were added. The Emulsion was then heat treated at 65 ° C and then cooled to 40 ° C. Then 464 mg of the spectral green sensitizing dye anhydro-5-chloro-9-ethyl-5'- phenyl-3 '- (3-sulfobutyl) -3- (3-sulfopropyl) -oxacarbocyanine hydroxide, sodium salt, per mole of silver added, whereupon the Emulsion was kept for 10 minutes. The chemical and spectral sensitization were relative to those used Sensitizer optimal.

Emulsion 7 (according to the prior art)

There was another emulsion of the US-PS 3,320,069 manufactured known type.

To 42.0 liters of a solution of 1.25% phthalated gelatin, concerning KBr 0,050 M, with respect to KI 0,012 M and concerning KSCN 0.051M, were stirred under the double inlet method added at the same speed and 68 ° C: a 1.37 M Potassium bromide and 0.053 M potassium iodide solution and a 1.43 M silver nitrate solution. The feed was over a period of 40 minutes. In the precipitation 21 moles Silver salt consumed. The emulsion was cooled to 35 ° C and washed by the coagulation method, and in the same As the emulsion No. 6.  

The pAg of the emulsion was adjusted to 8.8, whereupon the emuls 10 mg sodium thiosulfate pentahydrate and 2.0 mg potassium tetrachloroaurate were added in each case per mole of silver.

The emulsion was then heated to 55 ° C Cooled to 40 ° C and with 387 mg of the spectral green sensitizing Dye Anhydro-5-chloro-9-ethyl-5'-phenyl-3 '- (3-sulfobutyl) - 3- (3-sulfopropyl) oxacarbocyanine hydroxide, sodium salt per mole Silver added, whereupon the emulsion for 10 minutes on was saved. Chemical and spectral sensitization was optimal with respect to the sensitizers used.

Table VI

Characterization of Bromidiodide Emulsions 1-7

Emulsions 1-4 were silver halide high tabular silver halide grain size emulsions Aspect ratio according to the definition of the invention. Although some tabular grains of less than one diameter 0.6 microns in the calculation of average grain diameter knife of the tabular grains and in the determination of the processes tual projected area in these and the following examples were included - unless otherwise stated - were but insufficient amounts of tabular grains with such small diameters available to the given numerical values too distort.

To get a representative average aspect ratio for To obtain the grains of the comparative emulsions, the average grain diameter with the average grain compared thick. The projected area on the few tabular grains could be attributed to the criteria a thickness of less than 0.3 microns and a diameter of at least 0.6 microns, was in each case determined by visual observation. This area made, though at all, only a very small proportion of the total projected Area of the total grain population of the comparative emulsions.

B) Production of recording materials

The chemically and spectrally sensitized emulsions 1 to 7 were each applied to cellulose triacetate supports in the form of layers suitable for forming a magenta dye image. Each recording material thus contained a silver halide emulsion layer with per m ^{2 of support} surface: 1.07 g of silver and 2.14 g of gelatin. To the emulsions was added, prior to application, a solvent dispersion with the magenta image dye providing coupler 1- (2,4-dimethyl-6-chlorophenyl) -3- [α- (3-n-pentadecylphenoxy) -butyramido] -5-pyrazolone , 5-sec-octadecylhydroquinone-2-sulfonate, potassium salt and 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene. On a support surface of 1 m ² accounted for: 0.75 g of the coupler, 3.2 g of the potassium salt and 3.6 g of Tetraazaindens. A top layer of gelatin in a coating thickness of 0.88 g gelatin per m ² carrier surface, cured with 1.75% bis (vinylsulfonylmethyl) ether, based on the total gelatin weight, was then applied to the emulsion layer.

The obtained photographic materials were then 1/100 second through a step wedge with 0 to 3.0 Density levels and a Wratten # 9 filter and a 1.26 neutral Density filter exposed, using as a light source 600 watts, 3000 ° K tungsten lamp was used. The evolution of the recording Materials was carried out at 37.7 ° C according to a Farbentwicklungsver drive, as it is known from the reference "British Journal of Photo graphy Annual ", 1979, pages 204-206 times were changed to give fog densities of about 0.10 witness. The relative green sensitivity and the RMS granularity were determined in the case of each recording material. The RMS granularity was determined by a method such as by H. C. Schmitt, jr. and J.H. Altman in the journal Applied Optics, 9, pp. 871-874, April 1970.

The sensitivity-granularity ratio of the produced recording materials can be seen from the diagram presented in FIG. 3, in which the logarithm of the green sensitivity as a function of the RMS granularity × 10 is shown. It is clear from Fig. 3 that optimally chemically and spectrally sensitized high aspect ratio silver bromoiodide emulsions provide a significantly better speed-granularity relationship than low aspect ratio silver bromoiodide emulsions.

It should be noted that the use of a single layer format, in which the silver halide emulsions are coated in the same silver and at the same silver-coupler ratio lie, the best format represents the sensitivity-grainy behavior of a silver halide emulsion.  

Example 2 Improvement of the sensitivity-granularity ratio in a multilayer color photographic coupler containing recording material A. (prior art)

It became a multi-color recording material with color couplers prepared by the fact that the layers indicated below in the order given on a Cellulosetriacetat- Layers were applied:

Layer 1: Less sensitive cyan layer: from one red-sensitized silver bromoiodide emulsion, gelatin, a cyan image dye-forming agent Coupler, a colored coupler and a DIR coupler.

Layer 2: more sensitive cyan layer: from a sens more red-sensitized silver bromoiodide emulsion, Gelatin, one to create a cyan image dye the coupler, a colored coupler and a DIR Coupler.

Layer 3: Interlayer: Made of gelatin and 2,5-di-sec-dodecyl hydroquinone as an anti-discoloring agent.

Layer 4: Less Sensitive Purple Layer: From a green-sensitized silver bromoiodide emulsion (1.48 g / m ² silver), gelatin (1.21 g / m ² ) containing the magenta image dye-forming coupler 1- (2,4,6-). Trichloro phenyl) -3- [3- (2,4-diamylphenoxyacetamido) benzamido] -5-pyrazolone (0.88 g / m ² ), the colored coupler (1- (2,4,6-trichlorophenyl) -3 - [α- (3-tert-butyl-4-hydroxyphenoxy) - tetradecanamido-2-chloroanilino] -4- (3,4-dimethoxy) - phenylazo-5-pyrazolone (0.10 g / m ^2), the DIR Coupler 1- {4- [α- (2,4-di-tert-amyl-phenoxy) -butyramido] -phenyl) -3-pyrrolidino-4- (1-phenyl-5-tetrazolylthio) -5-pyrazolone (0, 02 g / m ² ) and 5-sec-octadecylhydroquinone-2-sulfonate, potassium salt (0.09 g / m ² ) as an anti-staining agent.

Layer 5: More Sensitive Purple Layer: From a more sensitive green-sensitized silver bromoiodide emulsion (1.23 g / m ² silver), gelatin (0.88 g / m ²⁾ , the magenta image dye providing coupler 1- (2,4,6-trichlorophenyl ) -3- [3- (2,4-diamylphenoxyacetamido) - benzamido] -5-pyrazolone (0.12 g / m ^2), the colored coupler 1- (2,4,6-trichlorophenyl) -3- [α -3-tert-butyl-4-hydroxy-phenoxy) tetradecanamido-2-chloroanilino] -4- (3,4-dimethoxy) - phenylazo-5-pyrazolone (0.03 g / m ²⁾ and 5-sec- Octadecylhydroquinone-2-sulfonate, potassium salt (0.05 g / m ² as anti-discoloring agent.

Layer 6: From gelatin and 2,5-di-sec-dodecylhydroquinone as Anti-stain agents.

Layer 7: Yellow filter layer: Of yellow colloidal silver and gelatin.

Layer 8: less sensitive yellow layer: from a blue sensitized silver bromoiodide emulsion, gelatin, a yellow image dye-forming coupler and an anti-staining agent of 5 sec octadecylphydro quinone-2-sulfonate, potassium salt.

Layer 9: more sensitive yellow layer: from a more sensitive one bluesensitized silver bromoiodide emulsion, Gelatin, a yellow dye Coupler and an anti-staining agent from 5-sec. Octadecylhydroquinone-2-sulfonate, potassium salt.  

Layer 10: UV-absorbing layer: From the UV adsorber 3- (di-n-hexylamino) allylidene-malononitrile and Gelatin.

Layer 11: Protective topcoat of: gelatin and bis (vinyl sulfonyl methyl) ether.

The silver halide emulsions of the individual color-forming layers of the prepared recording material contained polydisperse Silver bromide iodide grains of a low aspect ratio of from US-PS 3,320,069 known type. The emulsions were all in the presence of thiocyanate optimally chemically with sulfur and gold sensitized and spectrally compared to the corresponding Areas of the visible spectrum. The for the production of emulsion more sensitive to purple was composed a polydispersed (0.5-1.5 μm) silver bromoiodide emulsion of low aspect ratio (approximately 3: 1) with an iodide content of 12 M%, in a manner corresponding to the emulsion described No. 6 had been made.

B. (according to invention)

A second color photographic recording material was used in a similar manner with the exception, however, that the Making the more sensitive magenta layer a silver bromide iodide emulsion containing 8.4 M% iodide and tabular silver halide grains with a high aspect ratio instead of the emulsion the low aspect ratio was used. The average Grain diameter of the emulsion was about 2.5 microns. The thickness of the Grains was 0.12 μm or less and the average aspect ratio was over 20: 1. The projected area of the tabular Grains corresponded to more than 75%.  

The two high and low aspect ratio emulsions were correspondingly optimal chemical and spectral sensitized.

The produced recording materials were each 1/50 For a second through a multi-color step wedge with 0-3.0 density stages (plus 0.60 neutral density) with a tungsten lamp of 600 Watt 5500 ° K illuminated. The development duration in one color developer, as described in the reference "British Journal of Photography Annual, 1979, pp. 204-206 3 1/4 minutes.

The color developer had the following composition:
pH: 10.1-10.2

Sodium tripolyphosphate (Calgon) 2.0 g Sodium sulfite (anhydrous) 2.0 g Sodium bicarbonate or 8.0 g Potassium or sodium hydrogen sulfate 7.0 g potassium 1.8 g Potassium or sodium carbonate (anhydrous) 30.0 g Hydroxylamine 3.0 g Nitrobenzimidazole nitrate (0.3% solution) 10.0 ml

The resulting sensitometric results are as follows Table VII.

Table VII

Comparison of a high aspect ratio tabular silver halide silver halide emulsion with a silver halide emulsion having low aspect ratio three-dimensional silver halide grains in a multilayer multi-color recording material

Image-forming recording materials

From the values compiled in Table VII that when using a tabular silver emulsion Halide grains a considerable increase in green sensitivity occurs, with only a very small increase in granularity ness.  

Example 3 Enhanced sensitivity separation of spectrally sensitized Areas and areas of natural sensitivity

There were four different multi-color recording materials, hereinafter referred to as materials I to IV produced.  

Except for the differences specifically mentioned below the recording materials have the same structure.

Where:
DS, a gelatin topcoat; GFS a layer of colloidal silver in a concentration of 0.69 g / m ² ;
B is a blue-recording color-forming layer unit,
G is a green-recording color-forming layer unit and
R is a red recording color forming layer unit;
T tabular silver halide grains, ZWS an intermediate layer and the letters HE and WE represent a higher sensitive layer and a less sensitive layer, respectively.

The color-forming layer units without the letter "T" were prepared from low bromide silver iodide emulsions Aspect ratio as described in US Pat. No. 3,320,069, manufactured.

Corresponding layers of the individual materials showed, provided Unless otherwise stated, the same iodide content.

The higher sensitive tabular green sensitive Emulsion layers with the prefix "T" were obtained from Silver bromide iodide tabular silver halide emulsions emulsions, which in turn herge in the following manner were placed:

To 2.25 liters of an aqueous solution of bone gelatin with 1.5% by weight of gelatin which was 0.17 molar in potassium bromide, (Solution A) became equal at 80 ° C and a pBr of 0.77 early after the double-entry method within a period of time of 2 minutes at constant feed rate an aqueous 2.19 molar potassium bromide solution (solution B-1) and 2.0 molar Silver nitrate solution (solution C-1) at a consumption of 0.61% of the total silver nitrate used.

After this 2-minute inflow, the feed of the solution B-1 interrupted while the solution C-1 run so long was allowed to reach a pBr of 1.00 at 80 ° C, (2.44% of the total silver nitrate used). Thereupon became an aqueous solution of phthalated gelatin (0.4 liter of a 20% by weight gelatin solution) containing potassium bromide 0.10 molar (solution D) at a pBr of 1.0 and Allow to run at 80 ° C.

Then, for 24 minutes, solutions B-1 and C-1 were Inflow method into the reaction vessel (under Consumption of 44% of the total silver nitrate used), the feed rate was increased (4 times faster at the end than  at the start). After 24 minutes, the feed of solution B-1 while the solution C-1 still runs so much was allowed to reach a pBr of 1.80 at 80 ° C has been.

Then, after the double-inlet method, it became 12 minutes long Solution C-1 and an aqueous solution (solution B-2) of potassium bromide (2.17 molar) and potassium iodide (0.03 molar), under a consumption of 50.4% of the total used Silver nitrate. The feed rate was at the end of the addition 1.37 times faster than at the beginning of the addition.

After the double inlet method were then with constant Rate of an aqueous 0.36 molar potassium iodide solution (B-3) and a 2.0 molar silver nitrate solution (solution C-2) left until a pBr of 2.16 at 80 ° C was reached, corresponding to a consumption of silver nitrate of 2,59% of Total silver nitrate used. To prepare the emulsion A total of 6.57 moles of silver nitrate were used.

The resulting emulsion was cooled to 35 ° C and 0.30 Liter of an aqueous solution of phthalated gelatin (13.3 Wt .-% gelatin) and 2 × after the coagulation process washed.

The produced more green-sensitive emulsions layers of tabular silver halide grains formed by the prefix "T" are marked, lay a tabular silver bromide emulsion whose silver halide grains have a middle Grain diameter of 5.0 microns and an average grain thickness of about 0.11 μm. The tabular grains accounted for about 90% of the total grain projected area and had an average aspect ratio of about 45: 1. The more sensitive green and red sensitive emulsions Layers of materials I and II contained 9 mol% iodide, where  against the more sensitive tabular green and red senses emulsion layers of the materials III and IV 1.5 or 1.2 mol%. Iodide contained.

The higher green sensitive tabular silver halide emulsion Silver halide grains were then optimally spectrally and chemically sensitized by adding 350 mg of anhydro-5-chloro-9-ethyl 5'-phenyl-3 '- (3-sulfobutyl) -3- (3-sulfopropyl) oxacarbocyanine hydroxide, Sodium salt, 101 mg anhydro-11-ethyl-1,1'-bis (3-sulfopropyl) - naphth- [1,2-d] oxazolocarbocyanine hydroxide, sodium salt, 800 mg Sodium thiocyanate, 6 mg sodium thiosulfate pentahydrate and 3 mg Potassium tetrachloroaurate, each per mole of silver.

The higher red sensitive tabular emulsion layer Silver halide grains were prepared from a silver bromide iodide emulsion prepared with tabular silver halide grains whose Production and optimal sensitization took place in a manner that of the preparation of the green-sensitive silver bromide emulsion with tabular silver halide grains, except however, that 144 mg of anhydro-5,6-dichloro-1-ethyl-3- (3-sulfobutyl) - 3 '- (3-sulfopropyl) benzimidazolo-naphtho [1,2-d] -thiazolocarbocyanin- hydroxide and 224 mg of anhydro-5,5-dichloro-3,9-diethyl-3 '- (3-sulfo butyl) thiacarbocyanine hydroxide, each per mole of silver as a spectral Sensitizers were used.

Further details regarding the recording materials I-IV result from U.S. Patent 4,184,876.

The recording materials I-IV were the same illuminated by a 600 Watt 2850 ° K lamp for 1/100 second, using a No. 5 daylight filter and a step of a density range from 0 to 4 with density levels of 0.20. Other sections of the recording materials I-IV were exposed in a similar manner, but with additional Ver use of a Wratten # 98 filter to achieve blue  exposures. Further sections of the recording materials I-IV were exposed in the manner described, but under additional use of a Wratten No. 9 filter to achieve of minus blue lights.

All samples were in the same way after the color Negative C-41 developed as it is closer in the journal "British Journal of Photography Annual", 1979, page 204 is written. The development time was 3 minutes 15 seconds at 38 ° C. Of the developed recording materials were Yellow, purple and blue-green characteristic curves recorded. The curves of different specimens were at agree compared the minimum densities, d. H. by Overlay the minimum density sections of the curves. The results obtained are in the following Table VIII compiled.

Table VIII

Δ is the difference in the logarithm of the blue sensitivity of the blue recording color forming unit and the log of the blue sensitivity of the green recording color forming unit as determined by the equation

Δ = (B _W98 - G _W98 ) - (B _N - G _N );

Δ'is the difference in the logarithm of the blue sensitivity of the blue recording color forming unit and the log of the blue sensitivity of the red recording color forming unit as determined by the equation

Δ '= (B _W98 - R _W98 ) - (B _N - R _N );

Δ "is the difference in the logarithm of the green sensitivity of the green recording color forming unit and the log of the blue sensitivity of the green recording color forming unit determined by the equation

Δ "= G _W9 - G _W98 and

Δ '''is the difference in the logarithm of the red sensitivity of the red recording color forming unit and the log of the blue sensitivity of the red recording color forming unit as determined by the equation

Δ '''= R _W9 - R _W98 .

In the given equations mean:
W ₉₈ = Wratten filter 98
W ₉ = Wratten filter 9
N = neutral density filter

In a comparison of the recording materials II and III it follows that in the case of the material III, the use of of tabular silver halide grain emulsions was, superior sensitivity separations occur. Although in the case of the recording material III, not the sensitivity is achieved separations of the recording material I is too note that in the case of the recording material III no yellow Filter material was used and consequently not the Disadvantages occur when using such materials  to step. Although in the recording material IV larger amounts on yellow filter material were used as in the case photographic recording materials of the invention are required, show the recording material IV, that the Sensitivity separations of the recording material III, if necessary can be increased, even by using small yellow filter densities.

Example 3A

A monochrome recording material was prepared by coating onto a film support a more sensitive green-sensitized silver halide tabular grain silver halide emulsion layer as described above. A gelatin topcoat was then applied to this layer. The blue-minus-blue sensitivity separation of the recording material which was exposed and developed in the manner described was determined. The quantitative difference, determined according to the equation Δ "= G _W9 - G _W98 , was 1.28 log E. It follows that an advantageous partial blue-blue sensitivity separation can be achieved according to the invention if the minus blue recording emulsion layer is tabular Silver halide grains of a high aspect ratio of the light source used for the exposure is closest and is not protected by an overlying blue absorbing layer.

Example 4 Spectral blue sensitization of a tabular silver halide emulsion

A tabular silver bromide iodide silver halide emulsion grains (3 mol% iodide) was prepared in the following manner: To 3.0 liters of a 1.5% gelatin solution of 60 ° C at 0.17M Potassium bromide was added with stirring by the double-inlet method added: 4.34 M potassium bromide in a 3% gelatin solution and a 4.0 M silver nitrate solution within a period of time of 2.5 minutes, maintaining a pBr of 0.8 has been. It was 4.8% of the total silver nitrate used consumed. The feed of the bromide solution was then stopped, followed by 1.8 minutes of silver nitrate solution was consumed until a pBr of 1.3 was reached of 4.3% of the total silver nitrate used. simultaneously with the silver nitrate solution was then within a period of time of 24.5 minutes at increased speed (2.0 times faster at the end) a 6% gelatin solution with 4.0 M potassium bromide and 0.12 M potassium iodide while maintaining a pBr of 1.3, with 87.1% of the total used Silver nitrates were consumed. The feed of the bromide solution was then interrupted, whereupon the silver nitrate solution for a further 1.6 minutes was allowed to run long so that 3.8% of the total ver silver nitrate consumed until a pBr of 2.7 was achieved. The emulsion was then cooled to 35 ° C, whereupon 279 g of phthalated gelatin, dissolved in 1 liter of distilled Water was added and the emulsion after coagulation procedure was washed. The obtained silver bromoiodide emulsion (3 mol% iodide) had a mean grain diameter of about 1.0 μm, an average thickness of about 0.10 μm and an aspect ratio of about 10: 1. The tabular silver halide grains made more than 85% of the total projected area of silver halo  genidkörner the emulsion layer. The emulsion would become chemical with sodium thiocyanate, sodium thiosulfate and potassium tetrachloro aurat sensitized.

Recording material 1

A portion of the chemically sensitized emulsion was coated on a cellulose triacetate film support. The emulsion layer consisted of the tabular silver bromoiodide emulsion (1.08 g Ag / m ² ), gelatin (2.9 g / m ² ) containing a magenta dye-forming coupler: 1- (6-chloro-2,4-dimethylphenyl) -3- [α- (m -penta-decylphenoxy) butyramide] -5-pyrazolone (0.79 g / m ² ); 2-octadecyl-5-sulfohydroquinone (1.69 g / mole Ag) and 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene (3.62 g / mole Ag).

Recording material 2

A second portion of the tabular silver bromoiodide emulsion was spectrally sensitized to blue light by adding 3 x 10 ^-4 moles of anhydro-5,6-dimethoxy-5-methylthio-3,3'-di (3-sulfopropyl) thiacyanine hydroxide, triethylamine salt ( λ max 490 nm) per mole of Ag.

The spectrally sensitized emulsion was then used the same magenta dye-forming coupler, as described above, onto a cellulose triacetate film support carried.

The produced recording materials were then 1/25 For a second through a step wedge with / density levels from 0 to 3.0 exposed to a 500 watt 5400 ° K tungsten lamp. Thereupon were the recording materials in a color developer for 3 minutes from the British Journal of Photography Annual, 1979, page 204-206 known composition developed.  

The recording material 2 had a photographic sensitivity which was 0.42 log E units larger than the sensitive one speed of the recording material 1, resulting in an effective An sensitivity increased due to the blue sensitization gives.  

Example 5

This example illustrates the properties of Invention according to usable silver bromide emulsions.

A. Preparation of the emulsions Emulsion 1 (invention)

To 8.0 l of an aqueous 1.5% by weight bone gelatin solution, which was 0.14 molar with respect to potassium bromide were under vigorous Stirring after the double inlet process at constant feed rate Speed added: a 1.15 molar potassium bromide solution and  a 1.0 molar silver nitrate solution. The feed was 2 minutes long at a pBr of 0.85 at 60 ° C with consumption of 2.3% of the total silver nitrate used. Then one became 2.0 molar silver nitrate solution at constant feed rate Allow to run for 5 minutes until at a temperature of 60 ° C, a pBr of 1.2 had been obtained. Were 5.7% of the total silver nitrate consumed. Now were a 2.3 molar potassium bromide solution and a 2.0 molar Silver nitrate solution accelerated after the double inlet process admitted, d. H. 5.6 times faster at the end of the feed than at the beginning. The feed lasted 25.6 minutes at a monitored pBr of 1.2 at 60 ° C. This was 49.4% of the total silver nitrate used consumed. Then it was 5.4 at a constant feed rate Run a 2.0 molar silver nitrate solution for minutes, until a pAg of 8.25 was reached at 60 ° C. Were 7.7% of the total silver nitrate consumed. Now were a 2.3 molar potassium bromide solution and a 2.0 molar silver nitrate solution after the double inlet process at constant feed speed over a period of 49.4 minutes at over pAg of 8.25 at 60 ° C was added, with 34.9% of Total used silver nitrate were consumed. A total of About 11.3 moles of silver nitrate were used to make this emulsion used. Upon completion of the precipitation process, the emulsion became cooled to 40 ° C, whereupon 2.2 liters of phthalated gelatin solution (15.3 wt .-%) were added. The emulsion was then after Coagulation washing methods known from US Pat. No. 2,614,929 washed. Then, 1.9 L of 13.5% by weight bone gelatin solution, whereupon the emulsion at 40 ° C to a pH of 5.5 and a pAg of 8.2 was set.

The silver bromide tabular silver bromide emulsion obtained grains had an average grain diameter of 1.67 μm, an average thickness of 0.10 μm and an average Aspect ratio of 16.7: 1. The tabular grains made more than 95% of the projected area.  

Emulsion 2 (invention)

To 6.0 liters of an aqueous 1.5% by weight bone gelatin solution, which was 0.14 molar with respect to potassium bromide were under vigorous Stirred by the double jet method added: a 1.15 molar Potassium bromide solution and a 1.0 molar silver nitrate solution. The addition took place within 2 minutes at constant feed rate at a pBr of 0.85 and a temperature of 65 ° C with consumption of 1.6% of the total silver nitrate used. After a holding period of 0.5 minutes at a pBr of 0.85 and 65 ° C became a 2.0 molar silver nitrate solution for 7.5 minutes added until a pBr of 1.23 at 65 ° C was reached. In this case, 6.0% of the total silver nitrate used ver needs. Now, a 2.3 molar potassium bromide solution and a 2.0 molar silver nitrate solution at a controlled pBr of 1.23 at 65 ° C by the double jet method for 25.5 minutes accelerated added, d. H. 5.6 times faster at the end than at the beginning, wherein 29.8% of the total silver nitrate consumed were. Thereupon a 2.0 molar silver nitrate solution was added running at a constant feed rate for 6.5 minutes, until a pAg of 8.15 was reached at 65 ° C, with 6.4% of the Total used silver nitrate were consumed. Then were a 2.3 molar potassium bromide solution and a 2.0 molar silver nitrate after the double-entry procedure over a period of 70.8 minutes at constant feed rate at a pAg Value of 8.15 and a temperature of 65 ° C, wherein consumes 56.2% of the total silver nitrate used were. To prepare this emulsion, about 10 moles of silver were used nitrate used. After completion of the precipitation process, the Emulsion cooled to 40 ° C, whereupon 1.65 l of 15.3 wt .-% Solution of phthalated gelatin were added and whereupon the 2 × emulsion according to the coagulation known from US Pat. No. 2,614,929 washing process was washed. Then 1.55 l of a 13.3 % by weight bone gelatin solution. Furthermore, the Emulsion at 40 ° C to a pH of 5.5 and a pAg of 8.3 set.  

The obtained tabular silver bromide emulsion bromide grains was by an average grain diameter of 2.08 μm, an average thickness of 0.12 μm and a through average aspect ratio of 17.3: 1. The tabular grains accounted for more than 95% of the projected area out.

Example 3 (invention)

To 8.0 l of a 1.5% by weight bone gelatin solution, which was assayed for Potassium bromide 0.14 molar, were with vigorous stirring after the double inlet process at constant feed rate within a 2 minute period at controlled pBr of 0.85 at 60 ° C was added: a 1.15 molar potassium bromide solution and a 1.0 molar silver nitrate solution. Here, 3.6% of consumed total silver nitrate consumed. Now became a 2.0 molar silver nitrate solution with constant feed rate run for 5 minutes until a pBr of 1.2 reached at 60 ° C. For this purpose, 8, 8% of the total was used silver nitrate consumed. Now, a 2.3 molar Potassium bromide solution and a 2.0 molar silver nitrate solution accelerated added to the double jet process, d. H. 5.6 × faster at the end of the feed than at the beginning. The feed time was 25.5 minutes at a controlled pBr of 1.2 at 60 ° C. In this case, 75.2% of the total silver nitrate used consumed.

Now, over a period of 5.73 minutes, a 2.0 molar Silver nitrate solution added until a pAg of 7.8 at 60 ° C 12.4% of the total had been achieved used silver nitrate consumed. For the preparation of this emulsion In total, about 7.4 moles of silver nitrate were used. After finishing tion of the precipitation process, the emulsion abge on 40 ° C abge cooled, followed by 1.4 l of a phthalated, 15.3 wt .-% gelatin solution were added. The emulsion was then after that from the  U.S. Patent 2,614,919, which has been previously washed. Then, 1.3 L of a 13.5% by weight bone gelatin solution and, further, the emulsion was brought to a pH of 5.5 and a pAg value of 8.2.

The silver bromide tabular silver bromide emulsion obtained grains was by an average grain diameter of 1.43 μm, an average thickness of 0.07 μm and a through average aspect ratio of 20.4: 1. The tabular grains accounted for more than 95% of the projected area out.

Emulsion 4 (invention)

4.5 l of a 0.75% by weight aqueous bone gelatin solution, which was 0.14 molar with respect to potassium bromide were under vigorous Stirring by the double jet method within a period of time of 8 minutes at constant feed rate and a pBr Value of 0.85 run at 55 ° C: a 0.39 molar potassium bromide solution and a 0.10 molar silver nitrate solution. Were 3.4% of the total silver nitrate consumed. To a waiting time of 0.5 minutes at a pBr value of 0.85 55 ° C was 2.0 molar at constant feed rate Silver nitrate solution within a period of 18 minutes run until a pBr of 1.23 at 55 ° C was reached. In this case, 15.4% of the total silver nitrate used ver needs. Now, after the double inlet process, a 2.3 molar potassium bromide solution and a 2.0 molar silver nitrate solution at a controlled pBr of 1.23 at 55 ° C within 27 minutes accelerated added, d. H. 5.6 times faster at the end of the inlet as at the beginning, wherein 64.1% of the total silver nitrate used were consumed. Then, a 2.0 molar silver nitrate solution within a period of 8 minutes with constant inflow speed until a pAg of 8.0 at 55 ° C had been achieved. 17.1% of the total was used Silver nitrate consumed. To prepare this emulsion were used about 4.7 moles of silver nitrate. After completion of the off  precipitation process, the emulsion was cooled to 40 ° C, whereupon 0.85 l of a 15.3% by weight solution of phthalated gelatin were added. The emulsion was then 2 times after from the U.S. Patent 2,614,929 has been described for washing coagulation washing. Then, 0.8 L of a 13.3% by weight bone gelatin solution added and the pH of the emulsion to 5.5 and the pAg set to 8.3 at 40 ° C.

The silver bromide tabular silver bromide emulsion obtained Grains were characterized by an average grain diameter of 2.09 μm, an average thickness of 0.08 μm and an average aspect ratio of 26.1: 1. The blackboard shaped grains accounted for more than 95% of the projected area.

Emulsion 5 (invention)

To 6.0 l of a 1.5% by weight aqueous bone gelatin solution, the with respect to potassium bromide 0.14 molar, were under vigorous Stirring after the double inlet process at constant feed speed within a period of 16 minutes controlled pBr value of 0.85 at 55 ° C added: a 1.15 molar Potassium bromide solution and a 1.0 molar silver nitrate solution. there 3.4% of the total silver nitrate used was consumed. Now, a 2.3 molar potassium bromide solution and a 2.0 accelerated molar silver nitrate solution after the double inlet process d. H. 5.0 times faster at the end of the addition than at the beginning of the addition within 25 minutes at a controlled pBr of 0.85 added at 55 ° C. Here, 64.4% of the total used Silver nitrate consumed. This was followed by a 2.0 molar silver nitrate solution at constant feed rate for 15 minutes added until a pAg of 8.0 at 55 ° C had been reached. For this purpose, 32.2% of the total silver nitrate used ver needs. To prepare this emulsion were about 4.66 moles Used silver nitrate. After completion of the precipitation process The emulsion was cooled to 40 ° C, whereupon 0.85 l of a 15.3  wt .-% solution of phthalated gelatin were added. The Emulsion was then subjected to the coagulation washing procedure, as was from US Pat. No. 2,614,999. Then 0.8 l added to a 13.3 wt .-% bone gelatin solution and the Emulsion was adjusted to a pH of 5.5 at 40 ° C and a pAg Value set to 8.1.

The obtained silver bromide tabular grain emulsion was characterized by an average grain diameter of 2.96 μm, an average thickness of 0.08 μm and a through average aspect ratio of 37: 1. The tabular grains accounted for more than 95% of the projected area.

Emulsion A (comparison)

To 2.2 l of a 4.54 wt .-% aqueous solution of phthalated Gelatin was added with vigorous stirring at a pH of 5.6 after the double jet process at controlled pAg of 8.3 at a temperature of 70 ° C, an aqueous 3.5 molar potassium bromide solution and an aqueous 3.5 molar silver nitrate solution given. The halide and silver salt solutions became gradual according to the known from DE-PS 21 07 118 known method, namely in seven 4-minute time intervals with increasing inflow speeds, wherein the feed rate compared to the 1. Time interval in the second time interval was increased to 2.3 times, whereupon in the following Time intervals, the feed rate was increased in each case and 4 times, 6.3 times, 9 times, 12 times and 16 times in milli liters / minute from the beginning of the addition to the end of the addition. to Preparation of the emulsion was about 7.0 moles of silver nitrate ver applies. After completion of the precipitation, 0.4 l of an aqueous Added 10.0 wt .-% solution of phthalated gelatin at 40 ° C, whereupon the emulsion is 2 × by the method known from US Pat. No. 2,614,929 Coagulation washing was washed. Then 2.0 l an aqueous, 10.5 wt .-% bone gelatin solution, and the emulsion was adjusted to a pH of 5.5 and a pAg  from 8.5 at 40 ° C.

Emulsion B (comparison)

To 2.0 l of an aqueous, 1.25% by weight bone gelatin solution and 3.75% by weight solution of phthalated gelatin were added Stir at pH 5.8 558 g (0.6 mole) of Emulsion A added. Thereupon, after the double entry method controlled pAg of 8.3 at 70 ° C was added: an aqueous, 3.5 molar potassium bromide solution and an aqueous 3.5 molar silver nitrate solution. The halide and silver salt solutions were after the method known from DE-PS 21 07 118 stepwise in seven 4-minute time intervals accelerated added. The accelerated Addition corresponded to X, 1.2X, 1.5X, 1.8X, 2.0X, 2.4X and 2.7X ml / minute from the beginning to the end of the encore. About 6.4 moles of silver nitrate were ver except the seed for the preparation of this emulsion applies.

After the precipitation process, 0.65 l of an aqueous, 10 wt. % solution of phthalated gelatin at 40 ° C was added, followed by the emulsion is washed twice by the coagulation washing method has been. Then, 2.0 l of an aqueous, 10.5 wt .-% bone gelatin solution was added, and the emulsion was at 40 ° C on adjusted to a pH of 5.5 and a pAg of 8.5.

Emulsion C (comparative)

To 2.0 l of an aqueous 2.8% by weight bone gelatin solution and 2.2 wt .-% solution of phthalated gelatin were under Stirring at a pH of 5.7 1169 g (1.3 moles) of emulsion B added. Thereupon, after the double entry method added to a controlled pAg of 8.3 at 70 ° C: an aqueous, 3.5 molar potassium bromide solution and an aqueous 3.5 molar silver nitrate solution. The addition of the halide and silver salt solutions took place gradually according to the known from DE-PS 21 07 118 Procedure in twelve 4-minute time intervals at ge  increased feed with X, 1,2X, 1,3X, 1,5X, 1,6X, 1,8X, 1,9X, 2.1X, 2.3X, 2.5X, 2.7X and 2.9X ml / minute from start to finish End of the encore. About 5.7 moles of silver nitrate were added used to the seed for the preparation of this emulsion. To the precipitation process, 0.96 l of an aqueous 10 wt .-% were Solution of phthalated gelatin at 40 ° C was added, whereupon the Emulsion was washed 2 × after the coagulation washing procedure. Then, 2.0 l of an aqueous bone gelatin solution containing 10.5 g wt .-% was added, and the pH of the emulsion was on 5.5 and the pAg of the emulsion was adjusted to 8.5 at 40 ° C.

Emulsion D (comparative)

To 1.3 l of an aqueous, 5.07% by weight bone gelatin solution 1395 g (1.4 moles) of emulsion C were stirred at a pH Value of 5.3 added. Thereupon, after the double entry process at a controlled pAg of 8.3 and 70 ° C added: an aqueous, 3.5 molar potassium bromide solution and an aqueous, 3.5 molar silver nitrate solution. The halide and silver salt Solutions were added at an accelerated rate, within 60 minutes, d. H. 1.86 times faster at the end than at the beginning of the addition, wherein 89% of the silver salt solution used was consumed. Thereafter, the halide and silver salt solutions became constant Feed rate was added over a period of 5 minutes, 11% of the silver salt solution used was consumed. About 2.1 moles of silver nitrate were added to the seed Preparation of this emulsion used. After the precipitation process were 0.70 l of an aqueous, 10 wt .-% solution of phthalated Gelatin at 40 ° C was added, whereupon the emulsion 2 × after the Coagulation washing method according to US-PS 2,614,929 was washed.

Then, 1.0 L of an aqueous, 10.5 wt% bone gelatin solution was added and the pH of the emulsion was adjusted to 5.5 and the pAg was adjusted to 8.5 at 40 ° C.  

The physical properties of the emulsions produced are summarized in the following Table IX.

Table IX

B. Sensitization of the emulsions

The prepared AgBr emulsions with the tabular silver bromide grains and the octahedral AgBr comparison emulsions were optimally chemically sensitized and then optimally spectrally sensitized towards the green area of the spectrum, under the conditions given in Table X below. All  Numerical values refer to milligrams of sensitizer per mole of Ag.

Table X

C. Preparation of recording materials

The prepared tabular grain emulsions and comparative emulsions were separately used to prepare recording materials for the production of magenta images. The emulsions were for this purpose, after addition of a magenta dye-forming coupler, an anti-fogging agent and an anti-discoloration agents, as described in more detail below, applied to Cellulosetri acetate film support such that accounted for a support surface of 1 m ² 1.07 g of silver and 2.15 g of gelatin. The indicated additives were incorporated into the emulsion in the form of a solvent dispersion. A support surface of 1 m ² accounted for: 0.75 g of the magenta image dye-forming coupler 1- (2,4-dimethyl-6-chlorophenyl) -3- [α- (3- n -pentadecylphenoxy) butyramido] - 5-pyrazolone, 3.6 g of the anti-fogging agent 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene, sodium salt per mole of Ag and 3.5 g of the anti-staining agent 5-sec-octadecylhydroquinone 2-sulfonate, potassium salt per mole of Ag.

Gelatin top layers were applied to the emulsion layers applied at a coating thickness of 0.51 g / m ^{2 of} gelatin, which, with respect to the total gelatin content, was cured to 1.0% of bis (vinylsulfonylmethyl) ether.

D. Sensitivity-consistency comparisons

The produced recording materials became 1/100 second long with a 600 W 3000 ° K tungsten lamp through a step wedge with density levels of 0-3.0 and a Wratten filter # 9 as well exposed a neutral density filter of 1.2. The development was done using different development times of 1 1/2 to 6 minutes, to obtain matching veils at 37.7 ° C in a color developer of the type described in U.S. Pat British Journal of Photography Annual, 1979 Pages 204-206 is described.

Relative and granularity data were independently determined at 0.25 density units above the fog. A graph in which the logarithm of the green sensitivity is plotted as a function of the RMS granularity × 10 ³ is shown in FIG. 4. The logarithmic sensitivity is equal to 100 (1-log E), where E stands for exposure in lux-seconds at a density of 0.25 above the fog. As shown by the data obtained, the high aspect ratio tabular grain silver bromide emulsions of the present invention have superior speed-granularity ratios as compared with the comparative non-tabular silver bromide grain comparative emulsions.

E. Separation of the minus blue speed and the blue speed

Emulsions 1, 3, 4 and 5 with the tabular silver halide grains were mixed with Comparative Emulsions A, B and D with non- tabular grains in terms of their separation of the minus blue Sensitivity compared to the blue sensitivity. The Emulsions were optimally chemically and spectrally - as above be written - sensitized. The sensitized emulsions were then applied to the substrate and in a corresponding manner as above for the sensitivity-granularity comparisons written - developed. The exposure to the blue area The spectrum was 1/100 second long with a 600 W 5500 ° K Tungsten lamp through a step wedge with density levels from 0-3.0 and Wratten filters Nos. 36 and 38A. The minus blue exposure was done in the same way with the exception, however, that a Wratten filter no. 9 instead of Wratten filters 36 and 38A ver was turned. The relative sensitivity values became 0.25 Density units recorded above the veil. The obtained sensitometric results are shown in the following Table XI compiled.  

Table XI

As can be seen from the figures in Table XI show the tabular silver bromide emulsions significantly higher separations of blue sensitivity and Minus blue sensitivity on. The results obtained, optimally minus blue sensitized silver halide emulsions with tabular silver bromide grains of a high aspect ratio an increased separation of the sensitivity in the spectral minus Blue and blue areas show, compared to optimal sensibili based silver bromide emulsions with non-tabular silver bromidkörnern.

Example 6

This example illustrates the properties of silver bromide iodide emulsions with silver bromide iodide grains having uniform Iodide distribution.  

A. Preparation of the emulsions Emulsion 1 (invention)

To 30.0 l of a 0.8% by weight bone gelatin solution, which was found to be Potassium bromide was 0.10 molar, were after Doppeleinlaufver drive at constant feed rate with vigorous stirring added: a 1.20 molar potassium bromide solution and a 1.2 molar Silver nitrate solution. The addition took place within a time 5 minutes at a pBr of 1.0 at 75 ° C a consumption of 2.40% of the total silver nitrate used. Thereafter, 2.4 l of a 20 wt .-% solution of phthalated Gelatin was added and it was stirred at 75 ° C for 1 minute. thereon towards the described silver nitrate solution became constant running speed for 5 minutes until one pBr value of 1.36 at 75 ° C had been reached, under consumption of 4.80% of the total silver nitrate used. thereupon were accelerated after the double entry procedure, d. H. 2.4 × faster at the end than at the beginning of the addition at a pBr of 1.36 at 75 ° C was added: an aqueous, 1.06 molar potassium bromide and 0.14 molar potassium iodide solution, and further an aqueous, 1.2 molar silver nitrate solution. The addition took place within one Period of 50 minutes, until the silver nitrate solution was exhausted. In this case, 92.8% of the total silver nitrate used ver needs. To prepare the emulsion were about 20 moles Used silver nitrate. After completion of the precipitation process was The emulsion was cooled to 35 ° C, whereupon 350 g of additional phthalier Gelatin was added and stirred vigorously, whereupon the Emulsion three times according to the Koagu known from US Pat. No. 2,614,929 lationswaschverfahren was washed. Then 2.0 l became one Added 12.3 wt .-% bone gelatin solution, and the emulsion was added to a pH of 5.5 and a pAg of 8.3 40 ° C set.  

The obtained tabular silver bromide iodide emulsion Silver bromide iodide grains (ratio of bromide to iodide = 88: 12) was characterized by an average or average Grain diameter of 2.8 microns, an average or average Thickness of 0.095 microns and an average or average aspect ratio of 29.5: 1. The tabular grains did more than 85% of the total projected area of existing silver bromide iodide grains out.

Emulsion 2 (invention)

To 7.5 l of a 0.8% by weight solution of bone gelatin, the with respect to potassium bromide was 0.10 molar, were after the double with vigorous stirring added: a 1.20 molar potassium bromide solution and a 1.20 molar silver nitrate solution.

The addition was carried out at constant feed rate inside half of 5 minutes at a pBr of 1.0 and a temperature of 65 ° C with consumption of 2.4% of the total silver used nitrate is. After addition of 0.7 l of an aqueous, 17.1 wt .-% Solution of phthalated gelatin became the emulsion for 1 minute stirred at 65 ° C. Then a 1.20 molar silver nitrate solution at 65 ° C until a pBr of 1.36 was reached, 4.1% of the total silver nitrate used was consumed. Then, after the double jet process was accelerated, i. H. 2 times faster at the end than at the beginning of the addition, within 52 minutes at a pBr of 1.36 and a temperature of 65 ° C added: a halide solution containing potassium bromide 1.06 molar and with respect to potassium iodide was 0.14 molar and a 1.20 molar silver nitrate solution. This was 93.5% of the total consumed silver nitrate consumed. For the production of this Emulsion was used about 5 moles of silver nitrate. To the precipitate, the emulsion was cooled to 35 ° C, to a pH of 3.7 and according to the US-PS 2,614,929 washed washing process known. Then another 0.5 l of a Added 17.6 wt .-% solution of phthalated gelatin. After stirring for 5 minutes, the emulsion re-opened Cooled to 35 ° C. The pH was 4.1. The emulsion was then washed again after the coagulation washing procedure. Then were  again 0.7 l of an aqueous, 11.4 wt .-% solution of Bone gelatin was added, whereupon the emulsion at 40 ° C on a pH of 5.5 and a pAg of 8.3 was set.

The obtained silver bromoiodide emulsion (ratio of bromide to iodide = 88:12) with silver bromide iodide tabular grains characterized by an average grain diameter of 2.2 μm, an average thickness of 0.11 μm and a through average aspect ratio of 20: 1. The tabular grains accounted for more than 85% of the total projected area in the Emulsion existing Silberbromidiodidkörner from.

Emulsion 3 (invention)

To 7.5 l of a 0.8% by weight bone gelatin solution containing potassium bromide was 0.10 molar, were added with vigorous stirring added by the double jet method: a 1.20 molar Potassium bromide solution and a 1.20 molar silver nitrate solution. The Addition occurred at constant feed rate within 5 minutes at a pBr of 1.0 and a temperature of 55 ° C. This was 2.40% of the total silver nitrate used consumed. After addition of 0.7 l of a 17.1 wt .-% aqueous Dissolve phthalated gelatin and stir for one minute 55 ° C was at a constant feed rate, a 1.20 molar Add silver nitrate solution until a pBr of 1.36 is reached was. For this purpose, 4.1% of the total silver nitrate used ver needs. Now, after the double inlet process, a Halide solution which is 1.06 molar in potassium bromide and potassium iodide was 0.14 molar, and a 1.20 molar silver nitrate Solution added. The addition was accelerated, d. H. 2 × faster at the end than at the beginning of the addition within 52 minutes at a pBr of 1.36 and a temperature of 55 ° C. there 93.5% of the total silver used was consumed. to Preparation of this emulsion was about 5 moles of silver nitrate ver applies. Upon completion of the precipitation process, the emulsion became cooled to 35 ° C, adjusted to a pH of 3.7 and washed according to the washing method known from US Pat. No. 2,614,929.  

Thereupon, a further 0.5 l of a 17.6 wt .-% solution of phthalated gelatin added. After 5 minutes of stirring The emulsion was cooled to 35 ° C at a pH of 4.1 and washed again. Then another 0.7 l of a 11.4 wt .-% solution of bone gelatin was added, whereupon the Emulsion at 40 ° C to a pH of 5.5 and a pAg was set from 8.3.

The prepared tabular silver bromide iodide emulsion Silver bromide iodide grains (ratio of bromide to iodide = 88: 12) was characterized by an average grain diameter of 1.7 μm, an average thickness of 0.11 μm and a through average aspect ratio of 15.5: 1. The tabular grains accounted for more than 85% of the total projected area in the Emulsion existing Silberbromidiodidkörner from.

Emulsion 4 (invention)

To 7.5 l of a 0.8% by weight solution of bone gelatin, the with respect to potassium bromide 0.10 molar, were under vigorous Stirring after the double inlet process within 2.5 minutes at a pBr of 1.0 and a temperature of 55 ° C given: a 1.20 molar potassium bromide solution and a 1.20 molar Silver nitrate solution. The feed was carried out at constant feed speed. It was 2.40% of the total used Silver nitrate consumed. After addition of 0.7 l of a 17.1 wt. % aqueous solution of phthalated gelatin and one minute Stirring at 55 ° C at constant feed rate was a Add 1.20 molar silver nitrate solution until a pBr of 1.36 had been achieved. This was 4.1% of the total used silver nitrate consumed. Now after the double Incorporated within 52 minutes: one Halide salt solution which is 1.06 molar in potassium bromide and with respect to potassium iodide 0.14 molar and a 1.20 molar Silver nitrate solution. The addition took place within 52 minutes accelerated, d. H. 2 times faster in the end than at the beginning of the  Feed at a pBr of 1.36 and a temperature of 55 ° C. This 93.5% of the total silver nitrate used consumed. To prepare this emulsion were about 5.0 moles Used silver nitrate. After precipitation of the emulsion was this cooled to 35 ° C, adjusted to a pH of 3.7 and washed by the method known from US Pat. No. 2,614,929. Then again 0.5 l of a 17.6 wt .-% solution of added phthalated gelatin, whereupon the emulsion at a pH Value of 6.0 and a temperature of 40 ° C was redispersed. After stirring for 5 minutes, the emulsion again became a pH of 4.1 cooled to 35 ° C and washed again. Then were 0.7 l of an aqueous, 11.4 wt .-% solution of bone added gelatin, whereupon the emulsion to a pH of 5.5 and a pAg of 8.3 at 40 ° C was set.

The obtained tabular silver bromide iodide emulsion bromide iodide grains (molar ratio of bromide to iodide = 88: 12) was characterized by an average grain diameter of 0.8 μm, an average thickness of 0.08 μm and a through average aspect ratio of 10: 1. The tabular grains accounted for more than 55% of the total projected area in the Emulsion existing Silberbromidiodidkörner from.

Emulsion A (comparison)

In a precipitation vessel 9.0 l of an aqueous, 1.07 wt .-% were Solution of phthalated gelatin, which in terms of potassium bromide 0.045 molar, with respect to potassium iodide 0.01 molar and bezüg sodium thiocyanate was 0.11 molar. The temperature of the emulsion was brought to 60 ° C with stirring. In the precipitation vessel were then after the double feed process within 40 minutes constant feed rate and 60 ° C added: an aqueous Solution with respect to potassium bromide 1.46 molar and with respect to potassium iodide was 0.147 molar and a 1.57 molar silver nitrate solution. About 1 minute before the end of the double inlet was the inflow of Halide salt solution stopped. After completion of the precipitation  Process, the emulsion was cooled to 33 ° C and 2 × after the from coagulation washing method known from US Pat. No. 2,614,928 to wash. Then, 680 ml of a 16.5% by weight solution of bone was added added gelatin, and the emulsion at 40 ° C to a pH set by 6.4. During the double-feed, 4.0 moles Added silver nitrate.

Emulsion B (comparison)

This emulsion was prepared as the emulsion A with the Except, however, that the temperature was reduced to 50 ° C. and the total feed time of the solutions is reduced to 20 minutes has been.

Emulsion C (comparative)

This emulsion was also prepared as the emulsion A with with the exception, however, that the temperature was reduced to 50 ° C, and the feed time of the solutions was reduced to 30 minutes.

Emulsion D (comparative)

This emulsion was prepared as the emulsion A with the Exception, however, that the temperature was raised to 75 ° C, and the total feed rate of the solutions was 40 minutes.

The physical properties of the emulsions produced with the tabular grains and the comparative emulsions are in the following Table XII.  

Table XII

Each of Emulsions 1 to 4 and A to D contained 88 mol% Bromide and 12 mole% iodide. In each of the emulsions was the iodide practically uniformly distributed over the grains.

B. Preparation of Dye Images

The produced emulsion was optimally chemically treated with a pAg Value, set at 8.25 at a temperature of 40 ° C below the sensitized in the following Table XIII conditions. In the case of the tabular grain emulsions, a spectral sensitization at a pAg of 9.95 at 40 ° C before chemical sensitization, whereas in case of Ver same emulsions optimal spectral sensitization after chemical sensitization without further pAg value adjustment  took place. All stated numerical values refer to mg sensitizer per mole of Ag.

Table XIII

The differences in sensitization resulting from table XIII revealed were required in the case of the individual Emulsions each to achieve optimal sensitization. In the cases where the comparative emulsions in the same way chemical and spectral like the tabular emulsions Grains were sensitized, their sensitization was not optimal.  

To compare the results of an identical sensitization Tabular grain emulsion and a control emulsion To illustrate, proportions of the emulsion 2 and the emulsion C, hereinafter referred to as Emulsion 2x and Emulsion Cx, identical sensitized chemically and spectrally as follows:

Each emulsion was spectrally sensitized with 900 mg per mole of Ag Dye A at a pAg of 9.95 at 40 ° C, setting the pAg at 40 ° C on 8.2 and 20 minutes chemical Sensi stabilization at 65 ° C. with 4.0 mg potassium tetrachloroaurate per mole of Ag, 12.0 mg of sodium thiosulfate, pentahydrate per mole of Ag and 100 mg Sodium thiocyanate per mole of Ag.

The sensitized emulsions were coated separately on cellulose triacetate film supports such that a support area of 1 m ^{2 was used} : 1.07 g silver and 2.15 g gelatin. Prior to coating the emulsions on the supports, a solvent dispersion of a magenta image dye-providing coupler, antifoggant, and anti-staining agent was added to the emulsions.

The magenta image dye-forming coupler was 1- (2,4-dimethyl-6-chlorophenyl) -3- [α (3-n-pentadecylphenoxy) -butyramido] -5-pyrazolone. It was used in such a concentration that accounted for 0.75 g on a support surface of 1 m ² . The antifoggant consisted of 4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene, sodium salt. It was used at a concentration of 3.6 g per mole of Ag. The anti-staining agent was 5-sec-octadecylhydroquinone-2-sulfonate, potassium salt and was used at a concentration of 3.5 g per mole of Ag.

Cover layers of gelatin were then applied to the emulsion layers applied, with 0.51 g of gelatin being dispensed onto a support surface of 1 m ² . Curing was carried out with 1.5% bis (vinylsulfonylmethyl) ether, based on the total gelatin content.

The recording materials were then for 1/100 second with a 600 W 3000 ° K tungsten lamp through a step wedge with density stages from 0-3.0 and a Wratten filter no. 9 as well as a filter exposed to a neutral density of 1.8. The development time was 1 1/2 to 6 minutes to achieve matched levels of fog at 37.7 ° C in a color developer of the literature British Journal of Photography Annual, 1979, pp. 204-206 known type.

The relative speed and granularity values were determined independently at 0.25 density units above the fog. In the diagram of Fig. 5, the logarithmic green sensitivity in response to the RMS granularity × 10 ³ is set. As is apparent from Fig. 5, in the case of the silver bromide iodide emulsions containing the tabular grains, the sensitivity-granularity ratios are far superior to the corresponding ratios of the comparative emulsions.

Particularly informative are the sensitivity-granularity ratios of the emulsions 2x and Cx. In the case in which the emulsions 2x and Cx were chemically and spectrally sensitized in an identical manner, the emulsion 2x shows an even greater superiority over the emulsion Cx than in the case of a comparison of the emulsions 2 and C, both of which are optimally chemically and spectrally sensitized. This is particularly surprising because the emulsions 2x and Cx have substantially equal grain volumes per grain of 0.418 μm ³ and 0.394 μm ³ , respectively. To compare the relative separations of the minus blue sensitivities and blue sensitivities of the emulsions with each other, the emulsions were exposed to the blue region of the spectrum after sensitization and coating on a support as described. For this purpose they were 1/100 second with a 600 W 3000 ° K tungsten lamp through a step wedge with 0-3.0 density levels (0.15 density levels) and Wratten filter No. 36 and 38A and a neutral density filter of 1, 0 exposed. The minus blue exposure was carried out in the same manner except that a Wratten No. 9 filter was used in place of the Wratten No. 36 and No. 38A filters, and a 1.8 density unit neutral filter was used. The development took variously between 1½ and 6 minutes at 37.7 ° C in a color developer of the type described in British Journal of Photography Annual, 1979, pages 204-206. Sensitivity fog curves were recorded and the relative blue and minus blue sensitivities were determined at 0.20 density units above the fog. In the following Table XIV, the resulting sensitometric results are summarized.

Table XIV

As can be seen from Table XIV, the silver bromide iodide emulsions with the tabular grains a considerably larger Minus blue-blue sensitivity separation on than the comparison emulsions of the same halide composition. From these Results show that optimally sensitized silver bromide  high aspect tabular grain iodide emulsions ratio increased sensitivity in the spectral Range versus optimally sensitized conventional silver having bromide-iodide emulsions. If the iodide content decreases, then becomes a much larger separation of the minus blue and blue senses achieved, as can be seen from the earlier examples.

Emulsions 1, 2 and 3 and the comparative emulsion A, B, C and D were further compared to their sharpness. The for These investigations conducted sensitization, preparation Recording materials and development of the same occurred as described above. Modulation transfer functions for green Light was obtained by exposure of the recording materials different lengths, between 1/30 and 1/2 seconds at a 60% Modulation in conjunction with a Wratten filter No. 99. After Development was from the MTF curves, d. H. the modulation Transfer Function Modulation Modulation Transfer (CMT) Edges sharpening values determined at a 16 mm magnification. The invention According to emulsions used, green CMT edge acutance values from 98.6 to 93.5. In contrast, the comparative emulsions showed green CMT edge sharpness values of 93.1-97.6. The green CMT Edge sharpness of the emulsions 2 and C, the very similar through average grain volumes are shown in the following table XV compiled.

Green CMT edge sharpness Emulsion 2 97.2 Emulsion C 96.1

C. Making black and white pictures

The comparative emulsions were at 40 ° C to a pH of 6.2 and a pAg value of 8.2 and then optimally chemical  sensitized by addition of sodium thiosulfate, pentahydrate and potassium tetrachloroaurate. The emulsions then became one stand for a certain period of time at a certain temperature calmly. The emulsions were then spectrally sensitized by addition of anhydro-5-chloro-9-ethyl-5'-phenyl-3 '- (3-sulfo butyl) -3- (3-sulfopropyl) oxacarbocyanine hydroxide, sodium salt (Dye A) and Anhydro-3-ethyl-9-methyl-3 '- (3-sulfobutyl) - thiocarbocyanine hydroxide (Dye B), which are described in the following Table XXV.

The tabular silver halide grain emulsions were spectrally sensitized by the addition of dyes A and B at a pAg of 9.95 at 40 ° C before chemical sensitization with sodium thiocyanate, sodium thiosulfate, pentahydrate and potassium tetrachloroaurate given in the following table Temperatures.

Table XVI

The emulsions were applied in a layer thickness of ² m per 4.3 g of Ag and 7.53 g of gelatin on film support. All samples were cured with mucochloric acid (1.0% wt / gelatin). The emulsion layers were then covered with a cover layer of 0.89 g gelatin / m ² .

The method for determining the photographic modulation transfer functions is described in more detail in the journal "Journal of Applied Photographic Engineering", 6 (1): 1-8, 1980.

The modulation transfer functions were obtained by exposing at 60% modulation for 1/15 second using a 1.2 neutral density filter. The development of the exposed recording materials was carried out for 6 minutes at 20 ° C. in an N-methyl-p-aminophenol sulfate hydroquinone developer of the following composition:

Water, about 50 ° C 750 ml N-methyl-p-aminophenol 2.0 g Sodium sulfite, dehydrated 100.0 g hydroquinone 5.0 g Borax, solution 2.0 g Padded up with water 1.0 liter

After development, the modulation transfer (CMT) edge sharpness values at 35 mm magnification from the MTF curves determined (see Table XVI).

From the numerical values listed in Table XVI Clearly, the sharpness improvement that occurs when using Black tabular grain silver halide emulsions Achieve white recording materials.  

In order to be able to compare silver image sensitivity-granularity ratios, separate portions of the described recording materials were further exposed for 1/100 second with a 600 W 5500 ° K tungsten lamp through a 0-4.0 continuous density tablet and 4, 6 or 8 minutes at 20 ° C in the developer of the specified composition ent. Relative sensitivity values were measured at 0.30 density units above the fog and semispecific (green) RMS granularity determinations were made at 0.6 density units above the fog. Fig. 6 is a graph plotting logarithm sensitivity versus semispecular RMS granularity in the case of the 6-minute development.

The sensitivity-granularity ratios of the silver bromide iodide tabular grain emulsions are therefore far superior to the comparative emulsions. At development times of 4 and 8 minutes, corresponding results were obtained. In cases where matched contrasts were not achieved, the tabular grain emulsions had higher contrasts. As a result, the high-contrast tabular grain emulsions showed higher graininess than would be the case if the contrasts of the emulsions had been matched. Thus, while it is apparent from Fig. 6 that the tabular grain emulsions are clearly superior to the control emulsions to the extent that the tabular grain emulsions have higher contrasts than the comparative emulsions, the full extent of their superiority will be appreciated the sensitivity-granularity ratio is not illustrated.

Claims (23)

1. A multicolor photographic material comprising a support and emulsion layers thereon for separate recording of blue, green and red light, each having dispersed in a dispersion medium silver halide grains having an average diameter of not more than 10 microns, and green and red spectral sensitizing Dyes in the green and red light-recording layers, characterized in that at least one of the green and red light-recording emulsion layers contains chemically and spectrally sensitized silver bromide or silver bromoiodide tabular grains having a thickness of less than 0.3 micrometers and an average thickness of at least 0.03 microns, a diameter of at least 0.6 microns and an average aspect ratio of 8: 1 to 100: 1, and which make up at least 50% of the total projected area of the grains of the layer. 2. Photographic recording material according to claim 1, since characterized in that the tabular silver bromide or silver bromide iodide grains containing at least 50% of the total the projected area of the grains, a thickness of have less than 0.2 microns. 3. Photographic recording material according to claim 1, since characterized in that the silver halide grains of the green nes or red light recording emulsion layer of Sil Berbromidiodidkörnern with an average iodide hold from 0.05 to 20 mol%. 4. Photographic recording material according to Ansprü che 1 to 2, characterized in that the average Average aspect ratio of the tabular silver halide grains at least 12: 1. 5. Photographic recording material according to claim 4, since characterized in that the average aspect ver of the tabular silver halide grains at at least 20: 1. 6. Photographic recording material according to Ansprü che 1 to 5, characterized in that at least 70% of total projected area of grains of silver halide emulsion layer of the tabular silver halide grains come. 7. Photographic recording material according to claim 6, since characterized in that at least 90% of the total proji grained surface of the grains of the silver halide emulsion layer derived from the tabular silver halide grains. 8. Photographic recording material according to Ansprü che 1 to 7, characterized in that the silver halide grains of the silver halide emulsion layer up to 20 mol% consist of iodide.   9. Photographic recording material according to one of An Claims 1 to 8, characterized in that at least 50% the total projected area of the grains of blue light chemically recording silver halide emulsion layer and spectrally sensitized tabular silver halide grains whose thickness - with a diameter of min at least 0.6 microns - less than 0.5 microns lies and which has an average aspect ratio of greater than 8: 1. 10. A photographic material according to any one of claims 1 to 9, characterized in that at least one of the green and red light-recording emulsion layers chemically and spectrally sensitized tabular Silberbro mid- or Silberbromidiodidkörner containing a thickness of less than 0.2 microns, a Have diameters of at least 0.6 microns and an average aspect ratio of at least 12: 1 and which make up at least 70% of the total projected area of the silver bromide or silver bromoiodide grains in the emulsion layer and at least one of the tabular silver halide grains in the recording material with respect to the other Layers is arranged so that it is exposed during the Belich tion of the material at a color temperature of 5500 ° K in addition to the light to record the layer, the Einwir effect of blue light and that Δ log E of this emulsion Schi cht is less than 0.6, where:
Δlog E = log E _T - log E _B
where:
log E _{T is} the logarithm of the exposure to red or green light that is to record the layer containing the tabular silver halide grains, and
log E _{B is} the logarithm of the simultaneous exposure of the layer containing the tabular silver halide grains to blue light. 11. Photographic recording material according to claim 10, since characterized in that the recording material no Having a yellow filter layer and no yellow filter material, the or with respect to the light source over the tafelför arranged with silver halide grains containing layer is. 12. Photographic recording material according to Ansprü che 10 and 11, characterized in that at least one the layers with the tabular silver halide grains with respect to the blue light recording layer on ordered that they record before the blue light Layer is exposed. 13. Photographic recording material according to Ansprü che 10 and 11, characterized in that at least one the layers containing the tabular silver bromide or Sil berbromidiodidkörnern respect to the other layers such is arranged that they belich before these other layers tet is. 14. Photographic recording material according to Ansprü che 10 to 13, characterized in that both the green Light as well as the red light-recording layers ta containing shaped silver bromide or silver bromide iodide grains tende layers are. 15. Photographic recording material according to Ansprü che 1 to 14, with layer units for the separate Auf Drawing of blue, green and red light, its light recording layer units in such a way on a support are ordered that the recording material after the Belich  at a color temperature of 5500 ° K by a spek tral non-selective step wedge and development in relation on the blue contrast and the blue sensitivity green and blue Red contrast deviations of less than 20% and green and Red sensitivity deviations of less than 0.3 log E, at blue, green and red densities determined by the USA Stan dard PH 2.1-1952, and in which each of the color record layer units at least one silver halide having emulsion layer and the silver halide grains of at least one triad of silver halide emulsion layers for separate recording of blue, green and red Light with an average diameter of at least 0.7 micrometers are arranged so that they are the Be Light of the recording material used meets before it reaches the remaining emulsion layers, characterized in that at least 70% of the total per jied surface of silver halide grains made of silver bromide iodide grains exist, the red and green light drawing layers of the triad of tabular silver ha logenidkörnern whose thickness - at a diameter of at least 0.6 microns - at less than 0.2 microns ter and which has an average aspect ratio of have at least 12: 1 and which are chemically mixed with (a) gold and (b) sulfur and / or selenium are surface-sensitized, and that the material is free of yellow filter material between the light source and the green and red light recording Layers of the Triad is. 16. Photographic recording material according to claim 15, since characterized in that each of the green and red light triad recording layer units a minus blue Sensitivity is at least 10 × greater as their blue sensitivity.   17. Photographic recording material according to claim 16, since characterized in that each of the green and red light triad recording layer units a minus blue Sensitivity is at least 20 × greater as their blue sensitivity. 18. Photographic recording material according to claim 17, since characterized in that the blue sensitivity of the blue Recording in the recording material at least 6 × larger is the blue sensitivity of the minus blue record of the recording material. 19. Photographic recording material according to claim 18, since characterized in that the blue sensitivity of the blue Recording in the recording material at least 8 × larger is the blue sensitivity of the minus blue record of the recording material. 20. Photographic recording material according to Ansprü che 15 to 17, characterized in that the layersein separate recording of blue, green and blue red light, yellow, purple or blue-green dyes lie far away couplers included. 21. Photographic recording material according to Ansprü che 15 to 20, characterized in that the blue light recording emulsion layer of the triad more mol% iodide contains as the green and red light recording Emul layers of the Triad. 22. Photographic recording material according to Ansprü che 15 to 21, characterized in that one of the green and red light-recording emulsion layers of the triad is arranged so that on them the entire Belich light used in the recording material. 23. Photographic recording material according to claim 1, characterized in that the average minimum Grain diameter of the emulsion is 1.0 micrometers.