DE2116157A1 - Continuous mixer for the production of silver halide emulsions - Google Patents

Description

AGJ A-GEVAEET AG LEVERKUSEN '

Continuous mixer for the production of silver halide emulsions.

Priorities: Great Britain, April 5, 1970, note no. 15 9 ^ 8/70 Great Britain, April 3, 1970, note no. 15 950/70 Gevaert-Agfa N.V., Mortsel, Belgium

The present invention relates to a continuous mixer, a method of mixing in which such a device is used and, in particular, to the use of such a device in the display of silver halide photographic materials.

This invention has been made in the course of studies in Connection with the representation of fine-grained silver thiogenide emulsions. In these investigations it was found that emulsions with extremely fine grain size can be formed by dividing the substances that are to come into reaction with each other in very small Brings quantities together at the same time and generates shear forces during the precipitation through the entire volume of space of the mixture. The present invention provides an apparatus with the aid of which this principle can be applied in a rapid continuous mixing process can.

The device according to the invention comprises inner and outer bodies which delimit between them an annular passage through which the constituents can flow continuously from one end to the other; said bodies are relatively rotatable in order to expose the constituents in the passage to tangentially acting frictional forces and have such a facing surface shape that the frictional forces can induce shear stresses which generate turbulence throughout the entire volume of the liquid which passes through such a passage when the device is in operation.
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So that turbulence can be generated through the entire amount of space of the liquid that is located in the annular passage, the free space between the inner and outer body must be small. The maximum allowable free space depends in part on the relative rotational speed of the bodies that must be achieved. In general, the free space should preferably not be larger than 10 mm and most preferably not larger than 5 mm at any point in the passage.

Only very small amounts of liquid are in the annular passage brought together at every moment and precipitation reactions, as they occur in the preparation of silver halide emulsions, can be made such that the amounts of each other reacting substances that enter the annular passage are essentially completely used up at any time for nucleation and not essentially for grain growth.

It has now been found that the continuous representation of Silver halide grains by mixing aqueous solutions separately containing silver ions and halide ions, advantageously takes place in a flow mixer, which has a central inner body (rotor) and an outer body (cladding or housing) which surrounds the lateral surface of the rotor and in which the housing and the rotor are arranged coaxially and a free space or thin film space in the form of an annular one Form passage which has cross-sections that are constantly becoming smaller in a direction perpendicular to the axis of rotation, this

'.innfilmraüm in its larger cross-section serves as an inlet for the mixing zone that is formed between the rotor shell and the surrounding housing surface and that in its narrower cross-section serves as an outlet for the mixing zone, and in which the opposing walls that delimit the thin-film space are not perforated, are grooved smoothly or helically or have a roughness and / or point-like projections that contribute to To create turbulence in a liquid that is forced through

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walking through the free space, the Kotor and / or the housing with Drive means for his or her rotational movement (s) along said said Axis is / are provided and wherein the housing turns away from the region of the larger cross-sections, extends non-perpendicularly, preferably in alignment with the axis of rotation, over the rotor, and in which the head part of the rotor in the area of the larger cross-sections has a Has a surface that is free of guide slots that could isolate separated parts of the liquid

The device according to the invention can be used in a method for mixing a number of liquids which comprise a component or contain constituents which, when mixed, form a disperse phase, characterized in that the liquids to be mixed are continuously fed into a passage, through the entire cross-section of which the fed liquids flow into constant flow away from the inflow point (s) and within the same the mass of the liquid flowing through this passage is subjected to forces that essentially create turbulence through the entire amount of space

The components used are ζ · Β «, which in a chemical Reaction to form a solid disperse phase, like crystalline grains. In this regard, "especially silver halide grains should be mentioned, which are made up of a dissolved silver salt and a dissolved halide from separate aqueous solutions.

In such a process the various liquids, which contain components for a chemical precipitation reaction, fed continuously and separately into the mixing passage, the cross-sectional dimensions of which and the degree of turbulence are such, that the quantities of the reagents constantly entering the passage are essentially completely used up by nucleation and do not produce substantial mass grain growth.

The passage preferably has cross-sectional dimensions that correspond to the flow -Allow a liquid titan film no thicker than 5 mm

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The bulk of liquid in the passage preferably points at each point an average velocity component in the direction in which the liquid moves along the passage and is carried by all or substantially all of its tree quantity Amount of space in this passage exposed to shear loads creating a flow of turbulence.

Turbulent flow can be achieved by applying pressure to the entire mass of liquid in the passage in the direction of flow, which is sufficient to keep the Reynolds number well above the critical value hold at which see set turbulence flow conditions

Turbulent flow conditions can be created by in the same way ^ Moving one wall (or walls) of the culvert at sufficient speed or speeds to create the turbulent flow through frictional forces caused by the contact of the bulk of the liquid set with said moving wall (or walls)

Such is the case in the device according to the invention, in which the passage is an annular thin film space which is bounded by walls which constantly perform a relative rotation about an axis for the purpose of generation of frictional forces and wherein the amounts of liquid that are constantly entering the passage are mixed with the material that is in the passage was already exposed to thrust "

In a device according to the present invention, one or each F of the surfaces of the inner and outer body can be provided with a helical groove. However, so that the liquid in the groove or grooves is not shielded from the tangentially acting thrust forces, the slope of the groove should or each groove relative to the axis of rotation be greater than k $ degrees and the groove depth preferably not deeper than 5 mm enters this through the action of gravity, can remain there while said bodies perform several relative rotations.

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Because the cross-section of the annular passage towards the outlet end decreases, but the axial speed of the fed-in liquid in the direction of the outlet increases, the thrust forces occur change along the passage from the inlet to the outlet end

The opposing surfaces of the rotating relative to each other Bodies are preferably conical.

When operating the device, the best mixing results are achieved if it is noted that the shear load to which the mixture is subjected during its residence time in the annular passage is essentially is the same for all quantities of the mixture. This therefore means that all the quantities also remain in the passage for essentially the same length of time. Accordingly, there should be a constant flow from the point of influence or away from the points of inflow at all points of the passage prevail without any possibility that substantial parts of the liquid are in zones at different distances between the inflow point or points are random circulate·

While the invention was primarily made for use in the preparation of silver halide emulsions, inventions of the invention can Devices are used for the display of any dispersion, emulsion or suspension produced by mixing liquids and which are composed in such a way that the mixture causes the formation of a disperse phase. For example, a Liquid contain a dissolved substance that precipitates when the pH of the liquid is changed, or the other liquid may contain an ingredient that causes such a change in pH .

As another example, a liquid can be a solute while the other liquid may be a liquid that is miscible with the first, but not for such a body Represents solvent. Or else the various liquids can contain constituents that cause a precipitate to form react, e.g. of silver halide grains through the reaction of a

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soluble silver salt and a soluble balogenide · The invention Device can also be used for the purpose of reducing the size of the dispersed. Drops in an emulsion or on a continuous basis Melting thermoplastic material, e.g. to melt the noodles of a silver halide emulsion

In particular for carrying out chemical precipitation reactions, should be the different liquids whose mixture causes precipitation caused to be fed continuously and individually to the annular passage. Devices according to the invention therefore preferably include at least two feed devices to feed the two liquids separately into the annular passage · Preferably is the average diameter of the annular mixing passage in any plane perpendicular to the axis of rotation of the inner and outer Body substantially less than the length of the annular passage measured from the inlet to the outlet end of the same. The bottom this consists in the fact that it is necessary for the procedure on the one hand. keep the annular passage filled with liquid, while only small amounts of liquid are fed into the passage, while the passage, however, on the other hand, be sufficiently long must to ensure that the injected liquid material is exposed to shear forces for a long enough time. Preferably must the length of the passage must be at least 1.25 times greater than it should be average diameter.

The inner body of revolution is preferably inside the outer Body attached, the latter being non-rotatable. The inner body can have a spindle extending in the axial direction via which it is connected to a motor.

The device can be arranged, and preferably will be arranged in a vertical position of use, e.g. with an essentially vertically arranged axis, for relative rotation of the inner and outer bodies and for feeding the liquid material into the top of the annular passage by gravity.

According to a preferred design feature, the upper part of the

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inner body, which is rotatable (Botor), conical. The liquid one Material can be fed to the cone tip of the inner body, so that it then persists in. the top piece of the annular passage flows in.

The creation of means to the liquid material in the annular Feeding the passage under pressure is not ruled out, though Gravity conveying is preferred.

Important "for the representation of fine-grain silver halide emulsions and in the representation of various other dispersions with a small size distribution in the disperse phase it is Eeynolds' The number must be kept above the critical value that characterizes the transition from laminar to turbulent flow. It is evident that the critical "Seynolds number" can be partially realized by letting the liquid material flow into the annular passage under positive and constant pressure, in which Fall is the speed with which the bodies are set in relative rotation need to be to establish turbulent flow conditions, not needs to be large »However, in the currently preferred embodiments, the feeding of the liquid material takes place by gravity and the inner and outer bodies, which limit the annular mixing passage, rotate relatively to each other with sufficient Velocity to create turbulent flow conditions due to tangential frictional forces acting on the fluid the walls of the passage are exercised.

For the sake of simplicity, it should be assumed hereafter that only the inner body rotates, but it should be remembered that the forces of friction necessary to generate turbulence also by erosion of the outer body (hereinafter also referred to as the "housing"), relative to the inner body instead of the other way around, or by ionizing the inner body and the housing in opposite directions Establishments. Can arise.

Inner and outer bodies can be cylindrical or one of them or both may have a diameter which is different along its axis * with the thickness of the annular space at the end

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decreases towards which the mixed liquids flow out. Of the The inner diameter of the housing can therefore remain constant or decrease, while the outer diameter of the inner housing increases or both Diameters can increase, but to different degrees, or the outer diameter of the inner body can remain the same, while the inner diameter of the housing is reduced. Preferably are the inner profile of the housing and the outer profile of the inner body are conical towards the outlet end.

The opposing walls that delimit the layered space, can be smooth or have a degree of roughness and / or have point-like projections that help to achieve the required To generate turbulence. The turbulence can sometimes be promoted by constructing or using the device in such a way that the liquid in the mixing passage is subjected to frictional forces is. as a result of a relative movement of the walls that delimit the layered space, which are in the order of magnitude and / or Direction from one point to another along the liquid passage change. A change in the peripheral speed can occur suddenly if one or both bodies make a groove or on the surface Has or have grooves that have already been mentioned earlier «More or less large changes in the angular velocity can be caused by a change in the relative rotational speed of the bodies will. In addition or as an alternative solution, means can be provided to change the direction of rotation of the inner body to be able to while a given amount of liquid flows through, and / or the inner and / or the outer body can be made to vibrate in a direction that is parallel to the inlet / Outlet runs.

In the following, reference is made to the accompanying drawings, which represent :

Fig. 1 and Fig. 10 to 12 are schematic sectional views according to the invention Reactors for the passage of a liquid film;

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FIGS. 2 to 3 show different types of rotors for the one shown in FIG Device;

Figure k is a sectional view of a reactor for the continuous passage of a liquid film similar to the type shown in Figure 1;

Figure 5 shows a particular form of inlet for use with the A step of emulsifying a silver halide photographic emulsion using the mixer shown in Fig. 4;

Fig. 6 is a block diagram showing an electronic measurement and control system shows to control the inflow of ingredients for preparing a silver halide emulsion;

Fig. 7 is a flow chart showing production in continuous operation of photosensitive silver halide coating compositions with the aid of the mixing devices according to the invention;

Figures 8 and 9 are grain size distribution curves relating to silver halide dispersions made with the mixer of Figures h and 5 ;

Figures 10 through 12 are schematic sectional views of three others mixing devices according to the invention, the parts of which are provided with the same reference numerals which correspond to the parts in FIG.

The mixing device shown in Fig. 1 comprises a conical body 1 (rotor) which is set in rotation by means of a shaft 2 which is connected to a suitable drive means, such as an electric motor. The rotor 1 rotates in a conical chamber 3 «. The free space labeled C between the rotor 1 and the chamber 3 can be changed with the aid of adjusting means which contain a threaded bolt h. The constituents for the formation of a dispersion, for example by chemical reaction, emulsification, salting out or crystallization, are fed through separate inlets, pipes or fittings 5 into the hopper 6, which is formed by the upper part of the device. The mixture formed or the reaction products are discharged through a pipe 7.

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The upper section of the chamber 3 can be left open as shown, or can be light-tight depending on the requirement of the work to be performed be completed.·

The angles α and β shown in FIG. 1 do not necessarily have to be the same. The angle y can vary, for example, between 0 and 30 degrees. The part of the rotating body which is arranged inside the hopper 6 does not necessarily have to have a conical shape.

The diameters 0 and 0 ~ and the heights h ,. and h were chosen according to the mixing time and intensity required. Laboratory mixing devices can 20 cm high rotors cm with a diameter of 10 0, for example. Mixing devices for continuous operation for mixing fairly large quantities of constituents can have a rotor with a height of the order of 100 cm and a diameter of 0 at 50 cm

The diameter 0 of the rotor at the discharge opening can be very small provided that the mechanical strength of the lower rotor part is sufficient and that the rotor can still be properly balanced

The Mischgerat of FIG. 1 is normally operated in a vertical position, so that gravity towards supported along the annular mixing passage the flow of the liquid material to the outlet. However, the device can also be used in an inclined or even horizontal position. In the latter case, the rotor or the rotating chamber should preferably have a screw profile on the surface in order to keep the mixture two. To promote outlet.

When looking at the device, for example in a vertical position, the components that are to be mixed in liquid form are fed in a controlled amount continuously through the inlets 3 , and continuously into the annular ones. Mixing passage entered between rotor 1 and chamber · The liquid material flows downwards, on a helical path within the mixing passage, with the combined action of gravity and the frictional forces that arise

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the liquid act as a result of the high-speed rotation of the rotor 1. In the passage, the liquid materials are thoroughly mixed due to the thrust forces generated in the passage through substantially the entire volume of the liquid, whereby the entire liquid is in turbulent flow . Only very small amounts of liquid come into contact at any time at the inlet end of the mixing passage and such amounts are always forced to move from the inlet end to the outlet end.As a result, in the case of precipitation reactions, the substances that react with one another are essentially completely used up by nucleation with such small amounts of liquid , and not, or not to a significant extent, to bring about the grain growth.The importance of the features presented is evident from the fact that when a silver halide emulsion is represented, the average grain size of the finished silver halide emulsion increases when the substances that react with one another are at such a speed that an overflow occurs and they come into contact with one another above the rotor instead of in the annular passage · It is understandable that when using a Rotors without a screw-shaped profile for the purpose of pumping liquid, the speed of rotation and the free space between the rotor and the chamber must be such that effective friction and turbulent flow of the components still takes place. For this reason, according to a preferred embodiment, the thickness of the annular passage between the chamber 2j5 and the rotor is made variable by providing adjustment means k .

With reference to FIG. 1, it goes without saying that the rotor and the inner wall of the housing need not be conical and can have the geometric shape of another rotating body with a decreasing diameter. The rotor body can, for example, have a shape that corresponds to a curve that is part of a parabola, a hyperbola or an ellipse. In such cases the diameter of the rotor can still decrease from diameter 0. to diameter 0p.

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According to another embodiment, a rotor is used that has a generally conical shape but is helical Has circumferential groove with constant or changing pitch. The head surfaces or grooves can e.g. be conical, square, be sinusoidal, semicircular, or any other desired shape.

Figures 2 and 3 show two different other forms of the helical shape profiled rotor, which can be mounted in a housing according to Fig. 1. The rotor shown in Fig. 2 is the same provided with a helical groove, the depth of which decreases progressively towards the outlet end of the rotor, while the rotor diameter remains constant measured on the grooved messenger. The rotor shown in Fig. 3 is generally conical in shape and tapered . towards the outlet end, both at the threaded head and at the bottom of the threaded Groove. The cone angle along the groove head and along the groove bottom can be constant or different, so that the Depth of the helical groove remains constant or depending on the situation changes evenly.

Instead of causing the liquids to be displaced by a rotor rotates within a fixed chamber or housing, it is also possible for the fluids to be in a helical shape Follow the path by only turning the chamber or the chamber and the rotor turning in the same sense with different ones Rotate angular speeds or in opposite directions. For simple construction and efficient mixing, it is preferable to have a rotating internal body and a fixed one Housing to use.

Further devices for carrying out the invention are shown in FIGS. 11 and 12 shown. The components marked with the numbers 1, 2, 3, 6 and 7 have the same function as those with the same Reference numbers denote parts in FIG. 1.

In Fig. K a more detailed view of a laboratory mixer is given, which is particularly suitable for the representation of photographic silver halide emulsions in continuous operation. The rotor 1 is conical

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and provided with threads. The chamber 3, which surrounds the Ko tor ", i * st provided with a heating or cooling jacket 8, which has an inlet 9 and an outlet 10 for a heating liquid, steam or a coolant, has depending on the intended use. As an alternative solution, electrical heating means can also be used.

The free space between the chamber 3 and the rotor 1 is variable by means of a centrally arranged threaded screw h , which is a ball bearing

11 supports for the rotor. The rotor 1 is powered by an electric motor

12 driven, which is connected to a shaft 2, the vertical adjustment of the rotor 1 allowed. The mixer has an outlet 7 at the bottom and at least one inlet pipe 5 for feeding in the products to be mixed Components. The upper part 6 of the chamber is provided with a pneumatic or electric sensor 13. The sensor consists, for example, of a electrically insulated tube, which contains two electrically conductive needles that are electrically connected to the liquid materials in the mixer Make contact when these materials have reached a predetermined height. The resulting electrical signal (control signal) is on the tour control device of the gear pumps or other dosing means that regulate and / or will control the delivery of the components on a tour control device for the rotor 1 with a helical Transfer groove to increase the rotor rotation so that the flow rate of the liquids is readjusted and the Liquid cannot rise above a predetermined height

The free space between the chamber 3 and the rotor 1 is normally kept constant for one and the same mixing process, but can also be made adjustable if factors such as viscosity, mixing effect, reaction rate, heat transfer or volumes to be mixed within a certain time are taken into account pulls. The mixing efficiency increases in reciprocal relation to the free space, so that the so-called "thin film mixing" is to be given preference, the mixer working with a free space which, when measured between the outermost surfaces of the rotor and the chamber wall, is preferably 3 mm Laboratory mixers (rotor height 20 cm) should be and no more than 10 mm for industrial models (rotor height 100 cm). Of the

ORIGINAL JNSPECTED 109843/1656

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free space is preferably variable between 0.01 and 10 mm

To demonstrate the use of the device according to the invention for Precipitation of silver halide in continuous operation for the representation of photographic emulsions, particular reference is made to Figures 5 and 6.

Fig. 5 shows a specific intake system for Silbe'rhalogenidausfällung which is. K to view for a modification of the Einlassystems of FIG. The inlet system consists of three separate supply channels 14, 15 and 16 which are equipped with solenoid valves 17, 18 and 19, respectively. Apart from the inlet system, the mixing device is the same as shown in FIG. K , including a jacket 8 for a heating or cooling medium, for example steam or water. The dispersion formed in the mixer runs off again through the channel 7 (FIG. K) , which, as shown in FIG. 6, is provided with a thermometer and electrodes. The mixer is intended for operation in a vertical position and is held for this purpose by a support frame or by mounting brackets (not shown).

An aqueous silver nitrate solution is only used in a controlled amount fed through channel 14 and an aqueous solution of gelatin and a water-soluble halide, ζ · Β * potassium bromide or sodium chloride is fed in in a controlled amount through channel 15.

The channel 16 can be used for special ingredients as desired or to feed pH-regulating compounds into the emulsion-forming mixture. For example, such a channel can be used for this Entering an aqueous solution of ammonium hydroxide or acetic acid or other substances that affect the pH and grain growth influence.

The temperature of the reaction mass can be changed within wide limits will. According to the results to be achieved, however, it is normally below 80 degrees C. in the silver halide precipitation stage. held.

The processing time through the mixer is determined by gravity and / or determined by the pressure e.g. air pressure, as well as by the speed of the

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Rotcrc ;, through the rotor profile or the profile of the inner chamber walls and through the free space between the rotor and the chamber wall.

Because the flow in the annular passage around the eotor is high If turbulence happens, rapid contact is ensured between the reactants, which are present in a thin liquid film and not in large quantities as in batch processes. Only very small amounts of reaction substances may come into contact at the same time step. The resulting products are continuously and quickly drained from the mixer.

The formation of silver halide is a rapid chemical reaction, which takes place consistently in such mixers, so that large amounts of silver halide grains can be reproduced in a relatively short time Quality can be maintained

The substances that react with one another become vigorous with one another mixed under conditions that allow excellent temperature control without the need for any of the reactants to have to use in considerable quantities. The contact of small amounts of reagents with a short contact time (e.g. a fraction of a second up to a few seconds) and the rapid withdrawal of reaction products from the thin film mixer with turbulent flow makes it possible to produce SiI-berhalide emulsions that have a small grain size distribution and very small grain sizes, e.g. one grain size below 100 nm or even below 30 nm.

Silver halide precipitation can be used to achieve reproducible results at any time electronically control and regulate by means of signals obtained through constant measurements, as with reference to Fig. 6 is described. The outlet pipe 7 of the thin film reactor is equipped with a glass electrode 20 (pH value control), a silver electrode 21 (pAg value control) and a standard thermostated reference calomel electrode 22. The latter electrode is connected to the emulsion flow by means of a saturated potassium nitrate bridge 23, the potassium nitrate contains, e.g. absorbed in agar-agar. The voltage difference between 'the glass electrode 20 and the calomel electrode 22 is an

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electronic potentiometer 2k , which is calibrated in pH readings. The voltage difference that results between the silver electrode 21 and the calomel electrode is given to an electronic potentiometer 2f>, which allows millivolt readings, from which the pAg value can be calculated. The quantities of substance, such as acetic acid and water-soluble halide for correcting the pH and pAg values, are controlled by the solenoid valves 30 and 31, which are connected to the two process flow controllers 26 and 27, which are set in such a way that they have a preset pH or maintain the pAg value.

The output of the potentiometers 2k and 25 is given to the said process controllers 26 and 27 and the difference signal is used to control the solenoid valves 30 and 31. The electronic signals corresponding to the pH and pAg measurements are also sent to a galvanometer 32 with a writing device, so that a continuous diagram of the development of the pH and pAg values during the precipitation is recorded.

The temperature required to produce reproducible results is constant must be held, can be measured at the output with a resistance thermometer and the output signal is with a preset Control signal compared in a differential potential transformer. When the desired temperatures are reached, the difference between the two signals is zero. The difference signal becomes used, e.g. to control a needle valve at the inlet of the steam supply of the heating jacket of the conical mixer, or to control the number of revolutions of a motor connected to a gear pump that pumps the liquid coolant into the jacket. The outlet of the Mixing device can also be equipped with measuring devices to measure the turbidity, the spectral absorption and / or the conductivity of the to measure flowing liquid "

. Devices according to the invention can be used for the display of all types of photographic Emulsions can be used, e.g. neutral acidic and ammoniacal emulsions and according to a pre-selected program an adaptation to the different types of emulsification possible. the

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The way in which the constituents are added, the emulsification temperature and the excess of the halides present, either in constant or decreasing amounts, can easily be modified or changed. With regard to the form of emulsification, the common way of determining the amount of halide is by percentage excess over the equivalent amount of silver · iodobromide emulsions usually contain between 20 % and 250 % excess bromide during precipitation and ripening. Chlorobromide and chloride emulsions rarely contain more than 10 % excess halide, and the excess can be as low as 1 to 2 % in cases where very little grain growth is desired.

The amount of ammonium hydroxide, if used, can be fed into the silver nitrate solution, whereby silver oxide initially precipitates, which upon further addition of ammonium hydroxide dissolves and results in a solution of ammine complexes. As an alternative solution, the ammonium hydroxide can be contained in the halide / gelatin solution.

The pH of the precipitation mixture can in the case of ammoniacal Emulsions can be controlled to a large extent by the addition of ammonium hydroxide, but with other emulsions the pH during precipitation can be reduced critical and must therefore be carefully kept under control especially with regard to the production of small silver halide grains

The ratio of the various halides in the silver halide crystal and the order in which they are introduced can be easily checked and can, for example, consist of two or more in series Mixers are distributed · In this way it is easy to obtain mixed grain emulsions, e.g. as in the British patent 1 O27 1 ^ 6 has been described.

According to the last-mentioned method, a fine-grain emulsion is made with small grain size distribution produced first. After a break Chemical ripening is carried out after the precipitation, and then the precipitation is continued. An emulsion with silver halide grains is obtained which each consist of a chemically matured core, the

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covered with a layer of unripe silver halide.

The turbulent flow mixing according to the invention with a thin film is also suitable for the representation of silver halide demulsxons, in which the silver halide of the initially formed silver halide grains be completely or partially converted or replaced by another type of silver halide, e.g. a silver chloride part is replaced by replaces a bromide part without changing the grain size. Such a type of silver halide emulsion is called a "converted emulsion". ■

The cations of the halides used in the preparation of the emulsion are usually potassium or ammonium cations; cations of alkaline earth metal salts such as calcium chloride or other soluble metal halides can also be used. The latter can be introduced in larger or ψ smaller quantities for special effects, eg cadmium ions are used to delay the ripening process of the silver halides and to produce contrasting silver chloride and silver chlorobromide emulsions.

Various measures can be taken to delay grain growth as desired to be hit. It is known that the silver halide grains formed during precipitation are finer if the solubility of the Silver halide is lowest when the gelatin concentration is increased to a certain limit when the temperature is above the gelation point the gelatin is preferably between 30 and 40 degrees C, or if crystallization nuclei such as silver iodide or silver sulfide | are present.

It is also possible to retard the crystal growth by means of chemical compounds selected from the following groups, for example: imidazoles, thiazoles, thiolactic acid, i-phenyl-5-mercaptotetrazole, Nucleic acids, thiosulfates, cystine, thioglycolic acid and dithiopyrimidine. These grain growth inhibiting or retarding compounds can be added during the precipitation or the Silver halide dispersion can be added after it has left the turbulent flow mixer. It is of the utmost importance that " that in forming a silver halide emulsion in one

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inventive turbulence flow mixer under conditions' tire Promote the formation of fine grains, the addition of a retarder for the grain growth only when leaving the mixer through the emulsion takes place

Other useful grain growth retarders are mercaptotetrazole compounds, to which British patent specification 561 875 refers, the heterocyclic compounds or mercapto compounds described in US Patents 2 ^ 32 506 and 2 * t32 86 ^, in the French Patent specification 1 557 289, in Belgian patent specifications 710 602, and 723 ^ + 92, in German patent applications 2 053 023 · 8 and 2 O53 961o1 sulfonated heterocyclic mercapto compounds, ζ · Β » 2-mercapto-5-sulfobenzothiazole, 2-mercapto-8-sulfonaphthoxazole and 2-mercapto-5-chloro-7-sulfobenzoxazole, Selenium compounds, e.g. the diselenidr described in Belgian patent 7 ^ 7 012 e.g. diphenyl diselenide and p, p'-dichlorodiphenyl diselenide.

It is preferable to use grain growth retardants that are aromatic Cores included.

The use of devices according to the invention for the preparation of silver halide emulsions is of course not restricted to the preparation of fine-grain emulsions limited. It is also possible and desirable for various purposes that emanate from the turbulent flow passage Ripe the emulsion. This maturation can be carried out without the advantage of a uniform emulsion with a narrow grain size distribution is lost. Indeed, by physical Ripening the grain size distribution can be made even narrower.

A wide grain size distribution can be achieved by using the Performs precipitation on pre-existing grains, ζ-B. by re-enters the initially received grains into the working cycle or by performing a further precipitation in an or several interconnected mixers through which the emulsion produced first is fed back in.

The flow chart shown in Fig. 7 shows the continuous production of photosensitive silver halide emulsions in Verwen-GV.430 .

10 9 8 4 3/1 6 5 6 OWGINAL INSPECTED

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formation of a series of thin-film turbulence - jr-c ^ flussnii ö; he: .- n gemärks'Mg. τ-

The production begins with the precipitation of silver halide grains in a heatable and thermostated mixer M at a given temperature T. Said device is provided with two separate inlets hZ and ^ 3, one for the aqueous solution of silver nitrate and one for the desired halide and protective colloid, usually gelatin. The feed takes place in an amount that is controlled by the solenoid valves kk and ^ 5, which are controlled by signals generated by the control, regulating and writing unit k6, which has been described in more detail in connection with FIG. the unit is connected with a resistance thermometer ^ 7 a glass electrode ^ 6, a calomel electrode ^ 9 and a silver electrode 50th emulsion ¹ H obtained in the device is fed to the device 51, in which the emulsion a ripening treatment is subjected, at a temperature T which need not necessarily be the same as T; additional precipitation of silver halide on the already formed nuclei can take place, which results in crystal growth. Inlet 52 with control valve 53 is used to add additional silver salts, halides and / or silver halide solvents or to feed gelatin, e.g. phthaloyl gelatin '

The emulsion can be wholly or partly through the channel 5 ^, which is equipped with a regulating pump, into the circuit again to be fed in

After completion of the physical ripening, the gelatin is coagulated in a cheesy manner and precipitates together with the silver halide in the mixer 56. For this purpose, a suitable precipitant is fed in through the inlet 57 , which is provided with a control valve 50. An aqueous solution of ammonium sulfate can be used as the precipitant , organic sulfonic acids, for example polystyrene sulfonic acid, or simply a pH-reducing agent can be used if acylated gelatin has been added to the emulsion in the previous stages. The acylated gelatin is used in the emulsification stage or added at the end of ripening, which in the latter case is carried out above the isoelectric point of the gelatin *. In the coagulation stage

10: 384 3./-1656-

iuf about

> 3 acid is fed in through inlet 57 to reduce the pH to k , whereupon the gelatin coagulates. The coagulate, which is preferably in the form of a fine clot, is applied to an endless belt 59 which is designed like a sieve. A fine jet flushing water is drawn to the clot, for example from a channel 60 which extends over the entire length of the tape 59 extends · According to a particular embodiment, a second or third washing stage being introduced at a LABEL FOR with cooling mixer according to the present invention, which, however, has sieve-like perforated chamber walls through which the washing liquid flows out.

At the end of the washing stage, the clot is fed to the pouring funnel of a mixer 61 and is stirred vigorously at the correct rate Temperature and pH value, the clot is re-dispersed into it by new ones. The pH-controlling compounds and the water, which are delivered at the correct temperature are for the purpose of Eedispersion through the inlet 62, which is equipped with a control valve 63 is equipped, fed.

The redispersed silver halide crystals are, after they have achieved their distribution to the final grain size distribution and have been freed from impurities and superfluous halide ions, now in a suitable state that they can be mixed with chemical sensitizers in a mixer 65, which is equipped with connected to the mixer 61 through the outlet 6k .

In short, chemical sensitization of the emulsion consists of adding chemical compounds that increase its sensitivity to light. Sensitization involves a special heat treatment that is usually carried out after the sensitizers have been added. The treatment at elevated temperature, for example from 0 to 75 °, can last from a few minutes to a few hours until the desired sensitivity and maximum permissible fogging has been achieved. The chemical sensitizers are added in a controlled amount through the channel 86, which is provided with a valve 87 o The outlet 66 of the mixer 65 is connected directly or via an intermediate drum to a spiral 69, arranged in a large thermostat 70 which is connected to

109843/1656

the necessary temperature control unit 71 and Eührorganen 72 equipped is. The amount of emulsion that passes through the spiral determines the digestion time.

Three types of chemical sensitization are available for use in the digestion process, depending on the purpose envisaged: ") Sulfur sensitization,

2) Reduction awareness, and

3) Precious metal sensitization o

After completion of the chemical sensitization, the necessary additives to obtain the final photographic emulsion in ready-to-pour form are added, which is done through the channel 73, which is equipped with a valve 76, into the mixer 7h for mixing therein with the halide emulsion fed through the channel 73 · The ready-to-pour emulsion is drained into the application trough 77, in which the emulsion level is carefully checked. The drawing illustrates, as an example, the so-called trough application method for spreading onto a substrate in the form of paper or film 78, which are guided by guide rollers 79 and pass under a roller 80 which is arranged in such a way that the substrate 78 with the surface of the emulsion 81 in Coming into contact, which is kept at a precisely controlled temperature

To facilitate the transport of the photographic emulsion to and from the The various mixing devices used in their representation are similar, preferably in cascades or in a tower placed in a still tower so that gravity helps to facilitate the movement of the emulsion from one device to the other. When operating in light-tight containers, only the washing and application chambers need to be provided with the well-known dark room safety light, so that a large part of the processing takes place in normally lit workrooms can be executed.

Apart from its use for the preparation of silver halide emulsions, Devices according to the invention can be used in the representation of all types of suspensions and emulsions by means of physical or chemical reactions of all kinds, by which substances in

GV.43O 109843/1656

an iHL · ?. "zjn Pii-ic v.>. ■■ ,: *: - χ * ± be? '**'

Toll, .en- or drip e-nlcria- π
The device can: 3. can be used for the preparation of all kinds of soluble salts or complexes :; Turbulence flow conditions, cB Nickel'Iimethylglyoxim, BaSO ^, PbCrG ^, ZuGrO ^ ₁ -GdS, ZnS, and other phosphors, eg suitable for Fluoreözir-iisiühirme, metal oxides and hydroxides, ε · Β. HgO, Pb (OH), Te (OH) and Cr (OH) and metal particles, for example gold, mercury and silver dispersions, which are obtained by reduction. The device can also be used to salt out organic and inorganic compounds and to display types of polymer latex and all types of colloidal dispersions, starting with colloidal or polymer solutions.

Further examples for the use of the efficient devices exist in the representation vox. Emulsions in tiny droplets by feeding an ion containing larger droplets into the mixing passage, in which there is turbulence, so that the droplets are divided by the action of the thrust which is produced by the scarcest amount of water in the passage are «The ^creation of emulsions by mixing the materials that make the continuous and disperse phases in the device re.iiäss eer ilrfiridurj. generate s-llon. or the use of the device for pressu "r-.4ng the Trcpfciieiigr *: * .- o-3 ei: ier z uBefore prepared emulsion is \ on particular importance in de: / Um al £ .ij tion of Far'- Couplers that are used in photographic painting, zE at the Hrjrstellunf, van Oi - in gelatiiieenuilsioneii, »v-where the disperse phase contains a dissolved further coupler narrow distribution of the oil droplets is important for: .rr ^: iciVt «'u -.-; g-6iiiei ^v: equal coalition of the ki-urler on alone style . uio photographic material and for the nesting of images of low core quality «. It has also been found that emulsions exist. OEJ color couplers in gelatin which were prepared in a preferred Ansführungoform of the inventive device 'are not opalescent, sandsrn layers form, which are perfectly transparent when dry. In addition, these layers are more resistant to spoilage due to wrinkles than layers made from conventional emulsions. This is due to the very high elasticity of the layers. ; - Invention is the

GV.430 BATH ORIGINAL

109843/1658

-Zk-

211615?

Production of barium sulfate dispersions in a protective colloid for Formation of top layers on paper or other substrates "

In addition, the mixing device according to the invention can be used e.g. in the preparation of paints, varnishes, lubricants, cosmetic products, pharmaceuticals, foods e.g. fats, oils and Emulsions thereof «It can also be used as a flow-through thin film reactor for chemical processes, e.g. salt formation through precipitation, nitration, sulfonation, diazotation, coupling, hydrolysis, Alkylation, Friedel-Graft syntheses, acylation, esterification and Polymerization · According to a special embodiment, the mixing vessel is also suitable for mixing liquids with gases (e.g. under pressure) and for the reaction of liquids with gases, e.g. in chemical processes such as halogenation, amine formation through reduction, amine formation through ammonolysis, oxidation and hydrogenation. " According to one special training example, the gases are fed in through openings, which are provided in the rotor wall.

The mixing device according to the invention is in particular used as a reaction vessel suitable for chemical reactions in different non-mixing bears Liquid phases known as interfacial reactions. According to an interfacial condensation technique, polycondensates, polyamides and Polyester are represented.

Precise temperature control is very easy to maintain because there are no major ones Reaction masses come into contact with one another and they come into contact with one another in a thin liquid film in reproducible concentrations Achieve- The mixing device according to the invention can therefore also be used are used for the continuous melting of gels such as the noodles of a photographic gelatin-containing silver halide emulsion.

When using the device for chemical reactions, the reaction mass fed into the mixer anew and sent through a battery of mixers arranged in series are.

The application of the device according to the invention is illustrated by the following Examples demonstrated.

1098 43/1656

example 1

The following three solutions are prepared separately:

(A) an aqueous ammoniacal silver nitrate solution per liter Contains 0.857 moles of silver nitrate and 1.71 ^ moles of ammonium hydroxide,

(B) an aqueous halide solution containing 3 moles of potassium halide per liter contains (KBr / KCl / KJ - IOO / IO / I parts by weight),

(C) an aqueous acetic acid solution containing 3> 5 moles of acetic acid per liter contains,

(D) an aqueous 0.5% strength by weight gelatin solution.

With these solutions, the precipitation (emulsification) is made of photosensitive silver halide in a mixing vessel, which contains shown a delivery system according to FIG 5 and a housing and a Eotor as shown schematically on the figure h.

The height h. (Figure 1) of the rotor part in the conical chamber was 122 mm. The height h _? of the eotor part in the funnel was 65 mm. The diameter 0 of the eotor was 5 ^ mm and the diameter jZL 5 mm. The angles α and β were both 10 °. The clearance (c) was 1.5 mm.

In the rotor there was a helical groove with a right-angled Incised cross-section.

The width of the groove between the peaks of the thread was 7 mm, the width of the peaks 3 mm and the depth of the groove 1.5 mm · The rotor and the light-tight housing were made of stainless steel. The angular speed of the rotor during the precipitation was 76Ο rpm.

The solutions (A), (B), (C) and (D) were at the same time in the the following ratios through the separate inlet openings 1Α ·, 15, 16 and 29 as indicated in Figure 5, introduced:

Solution (A): 17 ^ ml per min

Solution (B): 1 ^ 8 ml per min.

Solution (C): 82 ml per min «

Solution (D): 280 ml per min.

109843/1658

When operating under these conditions, the contact time of the keagents in the thin film space was approximately 2.5 seconds.

The temperature was kept constant at ^ 9 ° during the precipitation. The pH and pAg values at the drain opening are expressed in mV measured were 8.15 and -35 mV, respectively. Right after the When the dispersion left the mixer, its pH was lowered to 5.00.

The apparatus was operated under the working conditions given above for 16 min. kept in operation.

The mean diameter of the obtained silver halide grains was 11 ^ nm. This diameter was determined on the basis of the specific adsorption · of a dye as described in Photographische Korrespondenz, Vol. 101, No. 3 (19 ^ 5), pp. 38-39 and by electron microscopic Measurement determined.

The grain size distribution curve in FIG. 8 shows that this distribution is very narrow. The ordinate shows the increasing ai grain diameters expressed in nanometers (nm), while the abscissa shows the number (K) which is expressed as the percentage? . .. α i-drner with a diameter smaller than the corresponding value in the ordinate. The diagram shows that 98 % of the grains have a size between 50 and 300 nm.

Example 2

This example relates to the manufacture of photographic prints Large size distribution silver halide emulsions by multistage treatment · The following solutions were used produced in a first precipitation stage:

(A) A mixture of 1.5 parts by volume of ammoniacal silver nitrate, those per liter are 3 moles of silver nitrate and 6 moles of ammonium hydroxide contains, and 3.5 parts by volume of demineralized water;

(B) a homogeneous mixture of:

a 3 molar aqueous solution of potassium bromide ^ fOOO ml a 3 molar aqueous solution of sodium chloride 300 ml of a 3 molar aqueous solution of potassium iodide 100 ml

109843/1656

demineralized water 2116157 2700 ml

Inert gelatin 500 g

enough aqueous ammonium hydroxide to obtain a pH value equal to 10.5 measured at 30 °

- First stage of precipitation

A mixing device 1 of the type described in Example 1 was used used, and the solutions (A) and (B) were through separate inlets in the ratio of 65 and 300 ml per Min. Introduced therein.

The angular velocity of the eotor was 500 during the precipitation RPM The temperature measured at the outlet was 62 °.

The pH and pH values measured at the drain port and expressed in mV pAg values were 10.8 and -I60 mV, respectively. This first stage of precipitation lasted 3 min.

- Second stage of precipitation

In the same. Mixing device as used in the first precipitation stage, the following solutions were introduced through separate inlet openings in the respective proportions:

- Liquid (A) as used in precipitation stage 1 in a ratio of 65 ml per minute

- Liquid (B) as used in precipitation stage 1 in a ratio of 300 ml per minute

- the dispersion which comes from the mixing device at the precipitation stage 1 was drained, at a ratio of 500 ml per min.

This second stage of precipitation took 2 minutes.

- Third stage of precipitation

The first precipitation step was repeated with the difference however, that the dispersion obtained from the second precipitation stage, together with the solutions (A) and (B) of the first stage were used · The introduction rates were the following:

- Solution (A): 65 ml per min.

- Solution (B): 300 ml per min

109843/1656

Yield of the dispersion of the second precipitation stage: 500 ml per minute The mean diameter of the obtained silver halide grains became measured with an electron microscope · It was 300 mn.

The results are shown in FIG. 9, from which it can be deduced that 98 % of the grains had a grain size between 10 and 1000 nm. The increasing grain diameters, expressed in nanometers (nm), are plotted on the ordinate of the diagram, while the number N (expressed as percentages) of grains with a diameter smaller than that which corresponds to the nm value is plotted on the abscissa.

Example _3

The following four solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous halide solution containing 0.3 moles of potassium bromide per Liter contains,

(C) an aqueous acetic acid solution containing 3.5 moles of acetic acid per liter contains,

(D) an aqueous 1% strength by weight gelatin solution.

With these solutions, the precipitation (emulsification) of the photosensitive silver bromide was carried out in a mixing vessel containing an intake system in accordance with FIG 5, and a housing and a rotor as shown schematically in the figure h.

The height h. (Figure 1) of the eotor part in the conical chamber was 122 mm. The height h_ of the rotor part in the funnel was 65 mm · The diameter 0 of the rotor was 5 ^ mm and the diameter 1 5 mm · The angles α and β were both 10 °. The clearance (c) was 1.5 mm.

In the rotor there was a helical groove with a rectangular shape Incised cross-section. The width of the groove between the peaks of the thread was 7 mm, the width of the peaks 3 mm and the depth of the Groove 1.5 mm · The rotor and the light-tight housing were made of stainless steel Made of steel. The angular speed of the rotor during the precipitation was 900 rpm.

GV.43Ο

109843/1656

The solutions (A), (B), (C) and (D) were introduced at the same time in the following proportions through the separate inlet openings 1 ^ 15, 16 and 2-9, as indicated in FIG. 5: Solution (A): 193 ml per min.
Solution (B): 16A- ml per min.
Solution (C): 58 ml per min.
Solution (D): 700 ml per min.

By operating under these conditions, the silver ion concentration, which was measured potentiometrically at the outlet of the mixer, was such that it coincided with a millivolt reading between + 300 and + ^ fOO mV. The pH of the emulsion leaving the device was between 3 and h * The contact time of the reagents in the headroom was approximately 2.5 seconds.

The temperature was kept constant at 35 ° during the precipitation.

The dispersion leaving the device became mu at such a rate an aqueous potassium bromide solution mixed, that in the mixed composition a voltage of +50 mV measured potentiometrically became.

The mean diameter of the silver halide grains obtained at the vent was 100 nm. The mean diameter of the grains was turbidimetrically as described in Sei.Ind.Phot. (2) Volume 19, November 19 ^ 8, pp. 401- ^ 18 and by measurement with an electron microscope certainly.

If 300 mg of 1-phenyl-2-tetrazoline-5-thione are used per mole of silver nitrate of the following tautomeric structure:

S = CN
I, 1

HN_ N <

in solution (B) was used as a grain growth retarder, and if one worked there under the conditions described above Obtained silver bromide grains with an average diameter of 20 nm.

αν. ^ o 109843/1658

Example ^

Barium sulfate was prepared using the apparatus like that of example 3, but which has an eotor without a helical Had circumferential groove.

There were two liquids (P) and (Q) separately in the slack inserted between the eotor and the housing ^

(P) an aqueous 1 molar sulfuric acid solution, (Q) an aqueous 1 molar barium chloride solution

The feed ratio of the liquids (P) and (Q) was 100 ml in 2 hours sec. Or "100 ml in 25 seconds. The liquids were introduced tangentially W to the rotor surface in the clearance and in the direction of rotation of the rotor. The clearance was 1.7mm wide, the. The temperature was 20 ° and the rotor speed was 815 rpm.

To compare the difference in grain size between barium sulfate, that from the same solution in a batch process (ΰ · η « in a vessel equipped with a helical agitator is) and the barium sulfate produced according to this example their deposition rates were measured.

A sample produced in a batch process, exhibited a 15 minute settling time in a sample tube. A sample made according to the continuous process of this example required the same degree of deposition (1 cm clear liquid at the top of the column) a 95 minute deposition time.

Example 5

A dispersion of ethyl cellulose in an ethanol-water mixture was prepared in the mixer as shown in FIG. The height of the rotor part in the conical chamber was 122 mm. The height of the rotor part in the funnel was 65 mm. The diameter j3 of the rotor was 5 ^ mm and the diameter 0 _? 5 mm · The angles α and β were both 10 °. The rotor had a smooth surface and was made of stainless steel.

GV.3

1098A3 / 1S58

*) 1 1 C 1 E "?

Two starting fluids, namely water and a 5% by weight Ethanol solution of ethyl cellulose N7 (trade name of The Hercules Powder Company Inc, Wilmington, Del ·, U.S.A. for a Sthyl cellulose, which is contained in a water-ethanol mixture (1/1 in volume) is insoluble) were introduced separately into the clearance between the rotor and the housing. The rotor speed was 930 rpm, the backlash 0, Mf mm and the temperature of liquids 20 °.

The water and ethyl cellulose solution were in proportions of 104 or 1 * f ml per minute introduced.

A batch process in which with a high-speed agitator was worked, and using the same liquids in the same volume ratio, resulted in a much coarser grain Dispersion as this, which was obtained with the continuously working mixer with turbulent flow according to this example.

Be i game β

The following four solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous halide solution containing 0.3 mol of potassium bromide per liter contained

(C) a 20 % ± aqueous acetic acid solution,

(D) a 1% strength by weight aqueous gelatin solution.

The photosensitive silver bromide was precipitated with these solutions - made in a mixing vessel with turbulent flow, which has a feed jet according to FIG. 5 and a housing and possessed a rotor according to the figure * f.

The height h (Figure 1) of the rotor part in the conical chamber was 122 mm. The height of the rotor part in the funnel was 65 mm. The diameter 0 of the rotor was ^ k mm and the diameter 0 ^ 5 mm. The clearance (C) was 1.5 mm. The pitch of the thread on the rotor was 6 mm. The depth of the groove was 2 mm and the width of the groove between the thread crests was 6.5 mm.

109843/1656

The eotor and the light-tight housing were made of stainless steel ⁰ * ^ '.

The angular speed of the rotor during the precipitation was 850 rpm. The solutions (A), (B), (C) and (D) were prepared at the same time by the separate supply openings 1 ¹ J-, 15, 16 and 29 as shown in Figure 5, is introduced.

Solution (C) was introduced at such a rate that has a pH of 3.5 in. at the drain opening of the device all experiments described below was obtained.

Solution (D) was used in all of the experiments described below at a ratio of 600 ml per minute.

The following Table 1 gives data which of sixteen different Experiments originate and show the evolution of the silver halide grain size as a function of the pAg value at the vent of the mixer with turbulent flow was measured. The pAg values and the density values (D) which correspond to the turbidity of the dispersions match were measured at 750 nm 1.5 min after the When the emulsion leaves the mixer, it is measured. The measurement was carried out in the cells of a spectrophotometer "Spectronic 505" (Trademark of Bausch and Lomb Inc., Koohester, N.Y., U.S.A.) performed.

The turbidity density is directly proportional to the grain size of precipitated silver halide "

The silver nitrate solution (solution A) and the potassium bromide solution (solution B) were introduced in an equimolar ratio at a flow rate of 152 ml per min. The one in the precipitation reaction maintained temperature was 35 °

Table 1

Attempt no. pAg value Density (D) . 1
2 2.75
3.15 0.31
0.30

10 9843/1656

211Ä157

3 3.65 0.34 4th 4.00 0.39 5 M5 0.51 6th 4.70 0.47 7th 4, 85 0.84 8th 5.60 0.46 9 5.85 0.43 10 10.00 0.50 11 9.20 0.33 12th 8.50 0.31 13th 7.80 0.40 14th 7.40 0.44 15th 6.50 0.52 16 6.30 0.52

The diagrams of Figures 13 and 14 were made in relation to the experiments 1 to 16 is obtained by plotting the Turbidi tat density C-D) against the Wavelength from 76O to 600 nm entered. Curves 1-9 of the figure 13 correspond to experiments 1-9 of the above table and curves 1-7 of FIG. 14 correspond to experiments 10-16 of this table.

It can be seen from these curves that in the region of low pAg values, i.e. from 2.75 to 6, the turbidity, m. A.W. the middle Grain size is minimal at the pAg value at which the solubility of the silver halide is also minimal (pAg = 3.00).

In the area of the higher pAg values 10 to 6, the turbidity is minimal at pAg = 8.5 because of the excess of halide ions in Relation to silver ions.

Example 7

The procedure was as in Example 6 with a pAg value of 7.9 (= 85 mV) at precipitation temperatures of 35 and 42 °, respectively.

In FIG. 15, curves 1 and 2 show the relationship between turbidity density (D) and wavelength (nm) in relation to silver bromide dispersions, which were produced at 35 and 42 °, respectively.

GV. 430

1Q9843 / 1S56

rbromids

From these curves it is evident that the grain size of the syllable
grows proportionally to the precipitation temperature.

Example 8

The following four solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous halide solution containing 0.3 moles of potassium bromide per liter and contained 2 wt. # gelatin,

(C) a 20 # aqueous acetic acid solution,

(D) an aqueous 1% strength by weight gelatin solution.

With these solutions the precipitation of photosensitive silver bromide was carried out made in a mixing vessel with turbulent flow as described in Example 6.

The angular velocity of the rotor was 85 ° during the precipitation RPM

Curves 1 and 2 of Figure 16 indicate the effect of the silver ions and halide ion concentration based on the grain size of the silver halide.

At the beginning of the precipitation these concentrations could easily be achieved by the addition of the solution (D), which acted as a diluent,
being controlled.

The working conditions for two experiments were chosen in such a way that the silver nitrate and potassium bromide in a first experiment
came into contact with the mixing vessel in concentrations of 0.05 mol / liter, while in a second experiment the concentrations at this contact amounted to 0.075 mol / liter. These conditions were
achieved »by adding the silver nitrate solution (A) and the potassium bromide solution (B) in equimolar amounts in a ratio of 152 ml
per min. and the liquid (D) in a ratio of
6OO and 3OO ml per min. For experiments 1 and 2, respectively. During this process, the pH value is kept at 3.5 by means of solution (C). The temperature was maintained at 35 ° .

109843/1656 oWGiNAL inspected

2118157

Emulsion patterns obtained from the mixing vessel were 1.5 min after taken from the formation of precipitation and its turbidity was measured as described in Example 6-

Curve 1 of FIG. 16 represents the dependence of the turbidity density of the wavelength of the sample obtained in Experiment 1, with 0.05 mol of silver nitrate and 0.05 mol of potassium bromide per liter in the Precipitation stage were used.

Curve 2 in FIG. 16 shows the dependence of the turbidity density of the wavelength for the sample obtained in Experiment 2, with 0.075 mol of silver nitrate and 0.075 mol of potassium bromide per liter were used in the precipitation stage.

From the curves in FIG. 16 it can be deduced that with a Increase in the concentration of the starting materials (silver and halide ions) the grain size of the silver halide increases, and that by the use of a low concentration solution, i.e. a solution containing approximately 0.05 per liter of each reagent, very fine grains can be obtained under the conditions described. The mean grain size of the silver halide grains obtained in Experiments 1 and 2 were 11 or 26 nm

Example 9

The following six solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous solution containing per liter 0.3 mol of potassium bromide and 2 wt.% Of gelatin,

(C) a 20 # aqueous acetic acid solution,

(D) an aqueous 1% strength by weight gelatin solution,

(E) an aqueous 1 N sodium hydroxide solution as the pH-controlling solution,

(F) as the solution controlling the pAg value, an aqueous solution of 0.03 mol Silver nitrate per liter.

The photosensitive silver bromide was precipitated with these solutions in a mixing vessel with turbulent flow such as

109843/1656

_ 36-

2116167

written in Example 6. During the precipitation, the Angular speed of the rotor 8 50 D / min · The curves 1 and 2 of the Figure 17 is an indication of the pH effect on silver halide grain size at a constant pAg value of 2.75

In a first test, represented by curve 1, has been the Niederschlägsreaktion at a pH of 3, 5 made whilst held represented by the curve 2, the precipitation at a pH value of 5 in a second experiment, ·

Küster of the emulsions produced in this mixer Taken 1.5 minutes after the precipitation and its turbidity was as described in example. «Measured

) The curve 1 of Figure 1? provides the. ÜTurbidität dependence of density (D) of the wavelength (nm) of the product of the first experiment is obtained by _t at a pH equal to 3 5 proceeded.

Curve 2 in FIG. 17 represents the dependence of the turbidity density (D) represents the wavelength of the product prepared according to the second experiment obtained at a pH equal to 5.0 became.

From the curves in FIG. 17 it can be deduced that the grain size of silver halide grows with increasing pH. The k mean grain size was in the first and second tests 11 or 36 nm

Example 1 0

The following four solutions were made:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous one. Halide solution containing 0.3 mol of potassium bromide per liter _as' 2 Gev.% Gelatin,

(C) a 20 # aqueous acetic acid solution,

(D) an aqueous 1% strength by weight gelatin solution.

With these solutions, the precipitation reaction of the light-sensitive GVA30

109843/1658

St.

silver bromide carried out in a mixing vessel with ' Flow with a Ziiführ.ungssystem according to Figure 5 and with a Housing and a Rotox as shown in FIG.

The height h. (Figure 1) of the eotor part in the conical chamber was 122 mm · The height of the eotor part in the funnel was 6.5 mm. The diameter 0 of the rotor was 5 ^L mm and the diameter 0 ^ was 3 mm. The clearance (C) was 1.5 mm.

The -Sötor and the light-tight housing were made of stainless steel. The angular speed of the eotor during the precipitation was 800 rpm

The solutions (A) ₁ (B), (C) and (D) were introduced at the same time through the separate inlet openings 1 ^, 15> 16 and 29, respectively, as shown in the figure.

The solution (C) was added in such a ratio that at a pH of 3.5 was measured at the drain opening of the device in all of the experiments described below.

The solution (D) was in a ratio of 600 ml per min · in all added to the experiments described below. The millivolt reading at the discharge opening was ^ 20 mV. Immediately after As the silver bromide solution exited the device, enough aqueous potassium bromide solution was added to bring the millivolt value to 50.

In experiment 1, which is the reference experiment, during the precipitation no grain growth retarder added.

In experiment 2, 1 ml of 20 # aqueous was used as a grain growth retarder Solution of poly-N-vinylpyrrolidone per 100 ml of emulsion that left the device, added.

In FIG. 18, curves 1, 3 and k show the dependence of the turbidity density on the wavelength of a sample of the product from experiment 1, 1.5 min., 10 min. And 20 min. After it Mixing vessel was taken from «Curve 2 shows the dependence of the turbidity density on the wavelength of a sample

ORIGINAL. INSPECTED

109843/1658

of the product from Experiment 2, 1.5 minutes after it was the mixer left. The turbidity was measured with a "Spectronic 505" ~ Spectrophotometer described in Example 6 was measured.

Example 1 1

The following four solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter,

(B) an aqueous solution containing per liter 0.3 mol of potassium bromide and 2 wt.% Of gelatin,

(C) an aqueous acetic acid solution,

(D) an aqueous 1% by weight gelatin solution

These solutions made the precipitation reaction of the light-sensitive Silver bromide carried out in a mixer with turbulent flow as described in Example 6. During the precipitation reaction the angular speed of the eotor was 900 rpm.

The solutions (A), (B), (C) and (D) were added at the same time through the separate inlet openings 1 ^, 15 ₅ 16 and 29, as shown in the figure, in the proportions of 190, 16O, 70 or 700 ml per min.

A number of experiments were carried out in which immediately after the silver bromide emulsion left the mixing vessel, 0.5 millimoles a grain growth retarder was added. The dispersion was measured to a millivolt reading with an aqueous potassium bromide solution of +50 mV (silver electrode / saturated calomel electrode).

Emulsion samples from the various experiments were then treated with an aqueous 20% strength by weight ammonium sulfate solution under the same conditions treated, and the precipitated, gelatin coated silver halide grains washed with 5 liters of demineralized water, the 0.25 millimoles of a grain growth retarder as used above.

The whole process of precipitation and washing of the emulsion grains took 1.5 hours. After each specimen had been stored at kO ° for 2 hours, specimens were removed and photographs of the silver bromide grains were taken in an electron microscope (50,000 times magnification).

109843/1656

The following table II shows the grain growth retarders used and the average silver bromide grain sizes achieved in the various experiments.

Table II

Attempt no Grain growth retarder N
/ \
S = CN
I II
HN N Medium grain
size 1 ' - 0
tZ ^ S ^S C = S
j Il J 60 nm 2 H ₂ NI ^ JI-NH hQ nm 3 0 30 nm S = CN
I Il,
HN N H
NN
f ^ ( y _s -cH ₂ Y ν k HO ₅ SI ₅ ^ Jl-N l ^ JI 22 no 5 18 nm

In FIG. 19, curve 1 shows the dependence of the turbidity density of the wavelength of a sample produced under the conditions of Experiment 1, 1.5 minutes after leaving

GVA30 ■

109843/1656

the misery's barrel it was removed. The curve 2: represents the speed of the Siirbidd.tat-Dieilte van der- 'wavelength of a sample which was produced and taken under the same conditions as in experiment k , 1.5 Kim. after it left the miseh jar.

Example 12

The following liquids (A) and (B) were prepared with regard to Their mixing in the mixer as shown in Figure 1 r

(A) a 10 wt. S & ge aqueous gelatin solution.,.

(B) dibutyl phthalate.

The height h of the Botorteil in the · kegelfarmig.es. Chamber was 122 mm «The height of the Eo tor part in the Erie & ter was & 5 mm. The diameter 0 of the botor was 5 ^ mm and the diameter C 5 mm. The angles ct and ß each amounted to 10 °. The clearance Cc) during the process was 0.87 mm · The rotor was now made of stainless steel. had a smooth surface. Its speed was 100 rpm.

The liquids (A) and (B) were introduced into the clearance on the upper part through separate inlet openings, the liquid (A) in a ratio of 700 ml in 3 min. 55 sec., The liquid (B) in a ratio of 8, 4 ml in the same period of time.

The temperature of the liquids in the mixing zone was ^ 0 °. the Liquid obtained at the drain port was reintroduced once into the mixer through one of the inlet ports.

The obtained emulsion was gelatin in a proportion of 12.5 g applied per m2 on a subbed cellulose triacetate carrier. Tests to measure the brittleness showed that the emulsion layer had much better resistance to damage by folding showed as layers which did not contain any dibutyl phthalate droplets.

The gelatin layer with the oil droplets was completely transparent when dry. With dimethyl phthalate were equally good Achieving results An even better elasticity was obtained by adding

10 9 8 4 3/1658 OftiGiWAi inspected

using exe,

x higher levels of dibutyl phthalate or dimethyl phthalate and this in the liquids in proportions of 11.2 ml or- 1 ^ ml per 3 JUin * 55 sec. introduced

This example shows, as in an analogous way, an emulsion of organic, hydrophobic liquid droplets which have a color coupler contained in a dissolved state in a colloidal hydrophilic binder can be produced in accordance with the present invention.

Example 13

The following four solutions were made separately:

(A) an aqueous solution containing 0.3 mol of silver nitrate per liter, and was diluted with 5 times the volume of distilled water

(B) 500 ml of an aqueous solution containing 0.3 mol of potassium bromide, 16 g of gelatin, 2.k8k ml of distilled water, 1000 ml of ethanol and 10 g of the grain growth retarder with the following formula:

(C) a dilute aqueous acetic acid solution,

(D) an aqueous solution containing 3200 ml of water, 800 g of gelatin and 5 g of the above-mentioned grain growth retarder.

Starting from these solutions, the precipitate of the light-sensitive silver bromide carried out in a mixer with turbulent flow as shown schematically in Figure 1, but in ^ which the solutions (A) and (D) in the center of the conical Rotor part in the funnel and the solutions B and C were added by spraying on the inner wall of the funnel

The dimensions of the mixer were as follows: h ^ = 91 mm
h ₂ = h3 mm
/ Zi ₁ = h2 mm
0 ~ - 6 mm.

109843/1658

The clearance (C) was 1.2 mm and the angular velocity was el Eotors during the introduction of these aqueous solutions 115QHi

Solutions (A), (B), (C) and (D) were in a ratio of 200, 205, 150 or 190 ml per minute added.

The pH value was kept at 3> 2 and the millivolt reading at the outlet opening, which is a measure of the pAg value, was + hkO mV if at a precipitation temperature of 38t! was worked. After precipitation, the millivolt reading was adjusted to 70 mV by mixing the precipitate with aqueous potassium bromide solution.

Samples taken from this treated precipitate were obtained a larger part of ^ silver halide grains with a grain size of 5 mn.

Example 1 ² *

A modified device of the type shown schematically in Figure h was used for melting silver halide emulsion noodles. The device did not contain an inlet system as shown in the figure, but the funnel was left open and served as a wide feed line into which the noodles were introduced. The height h (FIG. 1) of the eotor part in the conical chamber was 122 mm. The height of the cone-shaped kotor part in the funnel was 65 mm. The height h_ of the funnel was 150 mm and its diameter was 80 mm. The diameter of 0 Eotors was 5 ^ mm and the diameter 0 "5 mm. The free tree (C) was 0.8 mm. The eotor surface was incised in a helical shape with two parallel grooves. The pitch of the thread was 6 mm. The depth of the grooves was 3 mm and the width of each groove was 6.5 mm.

The noodles were introduced at 14 ° and the temperature of the das The eotors surrounding the housing were kept at V °. The angular velocity was 500 rpm. The introduction of the pasta happened at such a speed that the funnel during the Operation of the device was kept filled. The gelatin silver halide emulsion left the device in the sol state at 37 ° C.

109843/1656

The following two solutions were made separately:

(A) a solution of 150 g of polymethyl methacrylate in 750 ml of ethyl acetate,

(B) a solution of 300 g of gelatin, dissolved in 2100 ml of water, which contained 2,000 ml of a 20% strength by weight aqueous solution of the dispersant MERSOLAT (trade name of Bayer AG, Leverkusen, for a sulfonated paraffin).

These solutions A and B were introduced at the same time into the annular passage of a mixing vessel with a k in the figure housing and rotor "shown schematically.

The height Ir (see Figure 1) of the rotor part in the conical chamber was 122 mm. The height Ta ^ of the rotor part in the funnel was 65 mm. The diameter 0 of the rotor was 5 ¹ * mm and the diameter 0 ^ 5 mm. Both angles β and β amounted to 10 °. The scope

(C) was 1.7 mm

The rotor had a smooth surface and like that was lightproof Housing made of stainless steel.

The angular speed of the rotor during the mixing process was 1030 rpm.

Solutions (A) and (B) were in the proportions of 70 and 92 ml, respectively added per minute.

When working under these circumstances, the contact time of the reagents in the margin was approximately 2 seconds. The temperature was kept at hk ° during the dispersion process. The mean diameter of the dispersed polymethyl methacrylate particles was determined by microscopic measurement. It was 5000 nm.

The size distribution of the particles obtained in this process was much more homogeneous than in a batch dispersing technique Moreover, it is with the present mixing process with continuous flow in the form of a thin film possible, much more concentrated polymer solutions as well as less To use dispersants and gelatin as protective colloid.

109843/1656

211S1S7

example

Example 1J was repeated with the difference, however, that one an equal amount of the grain growth retarder according to one of the following geiidett structural formulas used:

Cl-

Cl-

C-SH

Silver halide grains which have the presence of such gerers were made. " owned a mean grain size lake of 5 nüU

10984-3 / 1656

Claims (1)

Claims iYj flow mixer that has a centrally located inner body ■ (rotor) and an outer body (casing or housing) which surrounds the outer surface of the rotor and in which the housing and the rotor are arranged coaxially and have a free or layered shape Form space in the form of an annular diameter, which has a cross section that is steadily smaller in one direction perpendicular to the axis of rotation, the layered space in its larger cross-section serving as an inlet for the mixing zone which is formed between the rotor shell and the surrounding housing surface, and in its narrower cross section as an outlet for the Mixing zone serves * and in which the opposing walls that the delimit layered space, are not perforated, smooth or helically grooved or have a roughness and / or punctiform Have projections which help to create turbulence in a liquid which is forced through said free space to flow through, the rotor and / or the housing being provided with drive means for its rotational movement about said axis is or are and wherein the housing, turning away from the area of the larger cross-sections, does not extend perpendicular to the axis of rotation extends the rotor, and wherein the head part of the rotor in the area of the larger cross-sections has a surface which is free of Guide slots that could isolate separated parts of the liquid. 2. Continuous mixer according to claim 1, characterized in that the housing extends beyond said rotor in extension with the axis of rotation. 3 «Continuous mixer according to claim 1 or 2, characterized in that that one or each of the opposing surfaces of the inner or outer body (rotor and housing) have a has helical groove, the inclination of which is greater than ^ 5 ° relative to the axis of rotation. 109843/1656 - k6 - H. Continuous mixer according to any one of claims 1 to 3, characterized in that the opposing surfaces of the bodies and the length of the annular passage are such that any amount of liquid that enters the passage as a result of gravity can linger in it during several relative rotations of this body · 3 ". Continuous mixer according to any of claims 1 to 3, characterized in that that the inner profile of the housing and the outer profile of the inner body taper towards the outlet end. 6. Continuous mixer according to claim 5, characterized in that the inner surface of the housing and the outer profile of the inner body are conical. 7 «continuous mixer according to each of claims 1 to 6, characterized in that that the inner body is set up for rotation and the outer body does not rotate. 8. Continuous mixer according to claim 7, characterized in that the inner body has an axially extending spindle, through which it can be connected to a motor. 9 «continuous mixer according to each of claims 1-ö, characterized in that that the device is arranged for the vertical position of use "10. Continuous mixer according to any one of claims 7 to 9, characterized in that that the top of the rotatable inner body has a top surface that slopes down from a central region to the periphery. 11. Continuous mixer according to any one of claims 1 to 10, characterized marked that the free space in the passage is not greater than 10 mm. 12. Continuous mixer according to claim 11, characterized in that animal-free space is not larger than 5 mm at any point in the passage. 109843/1656 13 · Continuous mixer according to any one of claims 1 to 12, characterized in that characterized in that the average diameter of the annular passage in each plane perpendicular to the axis of relative rotation the inner and outer bodies are substantially smaller than the length of the annular passage measured from the feed to the Drain end of the same. Ί ^ f continuous mixer according to claim 13, characterized in that that the length of the passage is at least 1.25 times greater than its length. 15 · Continuous mixer according to any one of claims 1 to 1A · characterized marked that it is in the section of the housing which extending beyond the inner body, having a device for feeding liquid material into the annular passage 16. Continuous mixer according to any one of claims 1 to 15, characterized in that characterized in that the housing of the continuous mixer contains a heating or cooling jacket. 17 · Continuous mixer according to each of the preceding claims, characterized in that the upper part of the device or the hopper is provided with a sensing device to measure the height to control the liquid introduced " 18. Continuous mixer according to any of the preceding claims, characterized in that the housing and body are connected to one another in such a way that the free space between the inner Wall of the housing and the outer wall of the body is between 10 and 0.01 mm or changes between these sizes. 19 · Continuous mixer according to claim 18, characterized in that the device contains a device to change the free space between 0.01 mm and 10 mm 2Oo flow mixer according to any of the preceding claims, characterized in that the annular space or passage between the housing and the body is variable by means of a 109843/1656 2118157 Device for moving the body and the housing relative to one another along the axis of rotation 21. Continuous mixer according to claim 1, characterized in that the free space between the housing and the inner body is variable is made by arranging the inner body in the area of the narrower cross-sections on a threaded bolt, which reduces friction Pressing means against the body. 22. Continuous mixer according to. Claim 21, characterized in that the friction reducing agent is a steel ball. 23 · Continuous mixer according to any one of the preceding claims, characterized in that characterized in that the body is a rotor that rotates around | said axis driven by a tour-controlled electric motor will. Zk. Continuous mixer according to claim 22, characterized in that the rotor is driven by means of an electric motor which is connected to a shaft which allows vertical adjustment of the rotor. 25 · Continuous mixer according to any one of the preceding claims, characterized in that characterized in that the housing is provided with a support frame or mounting brackets to hold the device in such a position, that gravity helps to mix those in the device Transporting substances. - 26. Continuous mixer according to any one of the preceding claims, characterized in that characterized in that the apparatus includes a hopper provided with a plurality of inlet pipes. 27 «Continuous mixer according to claim 26, characterized in that the inlet pipes are provided with a metering device. 2.8. Process for mixing and / or reacting substances, that is to say that it includes the following working steps: (1) Feeding said substances in a liquid medium into one layered or free space of a continuous mixer, GV.3 109843/1656 , which has a centrally located inner body (rotor) and comprises an outer body (housing or casing) which surrounds the outer surface of the rotor and wherein the housing and the rotor are arranged coaxially and have a free or layered Form space in the form of an annular passage having a cross-section that is perpendicular to the axis of rotation is constantly smaller, this layered space in its larger cross-section as an inlet for . the mixing zone is used, which is formed between the casing of the rotor and the surrounding housing surface and in its smaller one Section serves as an outlet for the mixing zone and in which the opposing walls that make up the layered space are smooth or are provided with a helical groove or a roughness and / or point-like projections which help to create turbulence in a liquid that is forced to flow through the free space, wherein the rotor and / or the housing is provided with drive means for his or her rotational movement, and the housing extends from the region of the larger cross-sections non-perpendicular to the axis of rotation, over the rotor, and wherein the top surface of the rotor in the area of the larger cross-sections has a surface that is free of guide slots that could isolate individual liquid parts (2) actuation of the rotor and / or the housing for relative rotation whereby the liquid medium is exposed to thrust forces which change along the annular passage, and (3) Removing or draining the liquid through the outlet ·. 29 «The method according to claim 28, characterized in that the to mixing ingredients are fed through separate inlets. 30. The method according to claim 28 or 29, characterized in that the ingredients to be mixed are fed in in a controlled ratio. 109843/1656 31 · The method according to any one of claims 2.8 to 30, characterized in that the assembly formed from said components is heated or cooled in the annular passage. 32. The method according to any one of claims 28 to 31, characterized in that that at least some of the substances fed are water-soluble chemical reagents that are in an aqueous medium are reacted in the annular passage. 33 «The method according to any one of claims 28 to 32, characterized in that that the substances are or constitute photographic components. 3 ^ · The method according to claim 33 »characterized in that as Reagents a water-soluble silver salt and a water-soluble halide are used, which are obtained from separate aqueous solutions to be introduced. 35 · The method according to claim 3 ^, characterized in that as Reagents Silver nitrate and a water-soluble chloride and / or bromide and / or iodide is used. 36. The method according to claim 3 ^ _5, characterized in that one of the introduced liquids is an aqueous ammonia-containing silver nitrate solution. 37 · The method according to any one of claims 33 to 36, characterized in that that the reagents are introduced from aqueous solutions in the presence of a protective colloid. 38. The method according to claim 37, characterized in that the Protective colloid gelatin. 39 · The method according to claim 37, characterized in that in silver halide crystals distributed in an aqueous medium can be formed in a first continuous mixing stage and in a second Mixing stage allows the crystals to grow. ^ fO. Process according to claim 3 _5, characterized in that in a first continuous mixing stage an aqueous dispersion of through 109843/1656 2118167 Gelatin coated silver halide grains is formed, and in a second mixing stage these coated silver halide grains through simultaneously introducing this dispersion and an appropriate amount of an inorganic salt into the annular passage be flocculated. * f1 · method according to Ansprych ^ -0, characterized in that the inorganic Salt is ammonium sulfate 42o method according to claim kO, characterized in that ₍ in a first continuous mixing stage an aqueous dispersion of gelatin-coated silver halide grains is formed, and in a second mixing stage these coated silver halide grains are formed by the simultaneous introduction of this dispersion and a corresponding amount of an organic sulfonic acid in dtn annular passage to be flocculated. hj>. Process according to claim ^ 2, characterized in that the organic sulfonic acid is polystyrene sulfonic acid. kk. A method according to claim k2, characterized in that in a first continuous mixing stage an aqueous dispersion of acylated gelatin coated silver halide grains is formed, and in a second mixing stage these acylated gelatine coated silver halide grains are formed by the simultaneous introduction of this dispersion and an amount of acid to reduce the pH Value to be flocculated to about ^ in the annular passage. ^ f? The method according to any of claims ^ O to Mt, characterized in that that pinned silver halide grains, which are surrounded with a protective colloid, by mixing with water in the ring-shaped Passage to be freed from excess salts. kS. Process according to any one of claims ^ O to h $, characterized in that flocculated silver halide grains which are surrounded with a protective colloid are freed from excess salts by being redispersed in the annular passage by mixing them in water. 109843/165 211S1S7 η · 7 · The method according to any one of claims 3 ^ - to 46, characterized in that that light-sensitive silver halide with respective ingredients of a photographic silver halide emulsion in the annular The passage is mixed 48. The method according to claim 47, characterized in that the Ingredients grain growth retardants, chemical sensitizers, Anti-fogging agents, stabilizers, development retarders, development accelerators , Developing agents, viscosity reducing agents, wetting agents, preservatives, thickening agents, Plasticizers, binders, hardeners, color couplers, makeup agents, filter dyes and spectral sensitizers are. 49 · The method according to claim 48, characterized in that the liquid medium flowing through the passage, an agent retarding the growth of silver halide grains is added and / or added to the liquid medium immediately after leaving the passage. 50. The method according to claims 34 to 41, characterized in that that the relative rotating speed of the inner body and the case and the feeding amount of the aqueous solutions are such are that silver halide grains with a grain size of 100 nm be generated· 51 · The method according to claim 50, characterized in that silver halide grains can be produced with a grain size below 30 nm. 52. The method according to any one of claims 34 to 38, characterized in that that in the annular passage silver halide grains with a large grain size distribution are produced by the precipitation is made in this passage on ready existing silver halide grains that have been introduced into this passage, by recycling the silver halide dispersion anew or by removing the precipitate in one or more annular passages whose outlets and inlets are connected to each other. GV.43O 10 984 3/1656 original 'inspected 53 «Process for the precipitation of silver halide grains, characterized in that that it comprises the following steps: (1) simultaneous introduction of a dissolved syllable compound and of a dissolved halide to be mixed in the passage of a continuous mixer, which has a centrally arranged inner body (rotor) and an outer body (casing or housing) which surrounds the outer surface of the rotor, and wherein the housing and the rotor are arranged coaxially and have a vacant or layered space in the form of an annular one Form a passage which has a cross-section that is constantly decreasing in a direction perpendicular to the axis of rotation, in its larger cross-section serves as an inlet for the mixing zone between the casing of the rotor and the surrounding Surface of the housing is formed and serves in its smaller cross section as an outlet for the mixing zone and in which the opposing walls that delimit the layered space are smooth, with a helical groove are provided or have a roughness and / or protrusions that contribute to turbulence in a liquid generate, which is forced to flow through the free space, wherein the rotor and / or the housing with drive means for the rotary movement of the inner and outer body are equipped, which is such that the friction of the liquid mass with the opposing walls of this body generated in it shear forces, resulting in a mixing of the components, and (2) the emptying of the obtained silver halide dispersion in the area of the smaller cross-sections. 5 ^ · Method according to claim 5 ^, characterized in that the Device contains one or more features which are described in any one of claims to 27. 55 «Method according to claim 53», characterized in that the free " Space between the inner surface of the housing and the outer surface of the inner body is between 0.01 and 2 mm. 1 098 A3 / 1656 - 5 ¹ * - 56. The method according to any one of claims 53 to 55, characterized in that that the housing has several inlet openings for separate Contains feed of constituents forming silver halide grains. 57 · Method according to any of claims 5 ^ to 57 , characterized in that the housing has a drain opening which is equipped with measuring and control means 58. The method according to claim 58, characterized in that said Average pH value, pAg value, temperature, turbidity and spectral absorption measurement and control means that can each be connected to a writer. 59 · Method of melting gelatin silver halide noodles, thereby characterized in that it comprises the following steps: (1) inserting said noodles into the flow passage of a Flow mixing device, which has a centrally arranged inner body (rotor) and an outer body (cladding or housing) comprises, which surrounds the outer surface of the rotor, and wherein the housing and the rotor are arranged coaxially and form a free or layered space in the form of an annular passage which one in a direction perpendicular to the Axis of rotation has steadily decreasing cross-section, which schichtförraige space in its larger cross-section as an inlet serves for the mixing zone, which is formed between the shell of the rotor and the surrounding surface of the housing and in his smaller cross-section serves as an outlet for the mixing zone and in which the opposing walls, which form the layered Delimit space, are not perforated or smooth, or are provided with a helical groove or have a roughness and / or have protrusions that help to create turbulence in a liquid that is forced through the free space to flow through, the rotor and / or the housing having drive means for his or her rotational movement are provided around said axis and wherein the housing extends from the region of the larger cross-sections over the rotor, ανΛ30 109843/1656 (2) heating the noodles in the passage so that they melt and are transferred from the gel form to the sol form, and (3) removing the gelatin silver halide sol from the area of smaller diameter 60.Method of mixing several liquids which contain constituents, which form a disperse or discontinuous phase by mixing, characterized in that the Liquids are continuously introduced into a passage, over the entire cross section of which the injected liquids in constant flow are kept away from the inflow point or the inflow points within which the flowing liquid Mass forces), which essentially generate turbulence through their entire volume of space 61. Mixing method according to claim 60, characterized in that the The components are a dissolved silver salt and a dissolved halide, which are added from separate aqueous solutions 62. Mixing method according to claims 60 and 6i, characterized in that that the various liquids contain components for a chemical precipitation reaction, and steady and individually fed into the mixing passage, with the cross-sectional dimensions this mixing passage and the degree of turbulence are such that the amounts of the constituents reacting with one another, which enter the passage at any, essentially all for nucleation and not essentially in bulk are used up to produce grain growth 63 · Mixing method according to each of claims 60 to 62, characterized in that that the passage has a cross section that corresponds to the flow of a liquid film, with a thickness of less allowed than 5 mm. Sk. Mixing method according to any one of claims 61 to Sk, characterized in that the liquid mass in the passage is an average at every point in the flow direction in the passage 109843/1656 211615? Having Geschwxndigkextskomponente, and 'essentially by their entire amount of space through in the passage is exposed to thrust loads that result in a turbulent flow. 65 « Mixing method according to claim 6k, characterized in that the turbulence flow is achieved by exerting a pressure on the liquid in the passage which is sufficient to keep the Reynolds number noticeably above the critical value at which turbulence conditions occur» 66. Mixing method according to claim 64, characterized in that one a turbulent flow is achieved by moving a wall or the walls of the passageway at sufficient speed or velocities moved in order to achieve a turbulent flow by frictional forces, which by contact of the liquid mass with the moving Walls is created. 67 » Mixing method according to claim 66, characterized in that the passage is a layered space which, for the purpose of generating such frictional forces, is constantly rotated in relative motion around an axis. Mixing method according to claim 67 , characterized in that the layered space has the shape of an annular space which is delimited by opposing rotating surfaces, and that the liquid within the passage is wholly or partially kept in turbulent flow by frictional forces caused by relative rotation such surfaces are generated around their common axis of rotation. 69 «Mixing method according to claim 68, characterized in that the Liquids are mixed in a device that contains an inner body that is rotatable within a radially symmetrical one Space, delimited by a surrounding housing or cladding and which thus delimits an annular layer-shaped space that can be kept filled with liquid material. GV.43O 109843/1656