Fuji Photo Film Company, Limited

Hiroshi Ohnishi

Yasunori Ichikawa

Shigeharu Urabe

Akira Kojima

Akira Katoh

Shigeru Yamaguchi

Chuzo Kobayashi

Noboru Higuchi

Keizo Matsui

Akira Kato

Hirokazu Yuhki

Mikio Ihama

Fuminori Arai

Tadaaki Tani

Kazuhiko Fujiwara

Sadao Kumazawa

A process and apparatus for producing silver halide grains wherein by removing water, etc., from a liquid containing fine, silver halide grains formed in a mixer and being added to a reaction vessel, the yield of the silver halide grains grown in the reaction vessel per unit amount of the raw materials used is increased. Also, by removing a portion of the water, used for the dilution, from the liquid being added to the reaction before the addition thereof, the amount of diluting water effective for the formation of silver halide fine grains in the mixer is increased, to thereby form finer silver halide grains in the mixer.

Process of producing silver halide grains and apparatus therefor

An apparatus for forming silver halide grains comprises a reaction vessel for causing the nucleus formation and the crystal growth of silver halide grains. The apparatus further includes: a mixer disposed outside of the reaction vessel and having a high-speed stirring blade; conduits for supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of water-soluble halide, and an aqueous protective colloid solution to the mixer while controlling the rotational speed of the high-speed stirring blade to form fine, silver halide grains; and a conduit for connecting the mixer to the reaction vessel for immediately supplying the fine grains in the mixer to the reaction vessel.

Apparatus for forming silver halide grains

A method and apparatus for manufacturing photographic photosensitive solultion to produce crystals of silver halide emulsion having a uniform size and shape and without substantial waste of expensive Ag.sup.+ solution. Flow control valves for controlling the flow rates of Ag.sup.+ and X.sup.- solutions are controlled according to a predetermined flow rate or pAg potential program and using output signals of respective flow meters or a pAg potentiometer. The flow control valves are motor-controlled flow control valves for which the rate of change of flow rate with valve stroke is small and linear.

Photographic photosensitive solution manufacturing method and apparatus

A process of producing silver halide grains by disposing a mixer outside of a reaction vessel for causing a nucleus formation and/or a crystal growth of silver halide grains and containing an aqueous protective colloid solution. The process further includes the steps of: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide(s), and an aqueous solution of a protective colloid to the mixer while controlling the flow rates of the solutions; mixing them while controlling the rotational speed of a stirring blade of the mixer to form fine, silver halide grains; and immediately supplying the fine grains into the reaction vessel to perform the nucleus formation and/or the crystal growth of the silver halide grains in the reaction vessel. The silver halide fine grains thus formed in the mixer are quickly diluted with a liquid withdrawn from the reaction vessel and then the diluted mixture is supplied to the reaction vessel.

Process of forming silver halide grains

A process of forming silver halide grains which comprises disposing a mixer outside of a reaction vessel for causing the nucleus formation and crystal growth of silver halide grains. The process further includes the steps of: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of a water-soluble halide, and an aqueous protective colloid solution into the mixer to form fine, silver halide grains therein; immediately supplying the fine grains into the reaction vessel; and performing the nucleus formation and crystal growth of the silver halide grains in the reaction vessel. The formation of the fine grains is controlled by controlling the flow rates of the solutions being supplied to the mixer and the r.p.m. of a stirrer provided in the mixer.

A method of dissolving a powder material is disclosed in which the material is wholly dissolved and the existence of bubbles in the resultant solution is greatly minimized. An agitating blade stirs a liquid in an air-tight tank while the powder material is inserted into the liquid. The pressure is then reduced in the tank causing large bubbles to swell. The bubbles are destroyed by the agitating blade. The pressure reducing operation is then turned off so that the bubbles do not leave the tank through a pressure reduction port. The pressure reducing operation is then repeated a number of times to dissolve the powder material and to destroy bubbles.

Dissolving and deaerating method

A control process and apparatus for the formation of silver halide grains comprising a mixer disposed outside of a reaction vessel containing an aqueous protective colloid solution and causing a nucleus formation (nucleation) and/or a crystal growth of silver halide grains. The process and apparatus further include: supplying an aqueous solution of a water-soluble silver salt, an aqueous solution of water-soluble halide(s), and an aqueous solution of a protective colloid to the mixer through supply conduits while controlling the flow rates of the solutions; mixing them while controlling the rotational speed of a stirrer of the mixer to form fine, silver halide grains; and immediately supplying the fine grains into the reaction vessel through a conduit connecting the mixer to the reaction vessel to perform the nucleus formation and/or the crystal growth of the silver halide grains in the reaction vessel. The control process and apparatus further comprise measuring the silver ion potential of the fine grains formed in the mixer or the silver ion potential in the reaction vessel with an electrode, and controlling the flow rate of at least one of the aqueous silver salt solution, the aqueous halide solution, and the aqueous protective colloid solution being added to the mixer, such that the measured value equals a predetermined value.

Control process and apparatus for the formation of silver halide grains

A flow control having a wide flow rate range and excellent linearity between the degree of valve opening and flow rate. The valve includes a cylindrical or conical valve head formed on a circular-truncated-cone-shaped working face which is tapered towards the outlet of the valve with the valve head being located inside the outlet-side casing. With respect to the area of the valve opening defined by the valve head and the valve seat, the valve head is shaped so that the rate of change of the flow rate with valve stroke is small and linear, whereby fine control of the flow rate can be accurately achieved over the entire flow rate range. The valve stroke to fully open the valve occurs in the inlet-side casing. A servo motor or the like is employed as the drive source for operating the valve.

Flow control valve

A dry analytical element for use in detecting a specific component contained in a liquid, which element comprises one or more water permeable layers provided on a water impermeable support, at least one layer of the water-permeable layers containing a composition capable of interacting with said specific component contained in said liquid. The composition contains a leuco dye and a dispersion containing said leuco dye is incorporated in the water-permeable layer, which is formed by dissolving the leuco dye in a hydrophobic solvent containing an aliphatic higher alcohol and dispersing the resulting solution in a hydrophilic medium. The leuco dye has the formula: ##STR1## where R.sup.1 represents an unsubstituted or substituted aryl group, R.sup.2 represents an unsubstituted or substituted alkyl group, and R.sup.3 represents an unsubstituted or substituted aryl group. A process for producing said dry analytical element is also disclosed.

Dry analytical element and process for producing the same

A powder measuring device and powder measuring mixer in which powder is supplied from a supply hopper to a measuring hopper with its flow rate controlled by a flow regulator associated with the hopper. The weight of the measuring hopper is monitored. A controller compares the measured weight with a target rate to produce a deviation therebetween and a time variation of the deviation. The controller operates according to fuzzy inference to produce a desired flow rate for the next control cycle. This desired flow rate is then supplied to the flow regulator. Several supply hoppers with associated flow regulators can be used. Then the output of the controller is switched between the different flow regulators at different phases of the mixing measurement. Additionally, the measuring hopper can be movable between the different supply hoppers so as to avoid complicated piping.

Powder weighing mixer and method thereof

A measuring mixer for use with either liquids or powders in which different supply systems supply different stock liquids or powders to a receiving container from supply containers. A continuously variable flow regulator is associated with each supply container. The cumulative weight of the receiving container is measured and compared with a target weight. Then a computation section calculates a desired flow rate based upon both the deviation from the target weight and a time variation thereof. This calculation is preferably done according to fuzzy inference. The desired flow rate is then used to control a selected one of the flow regulators so that the measurement is sequentially performed between supply systems. Optionally, the receiving container can be movable between the different supply systems.

Controlling method and a measuring mixer for liquids and powders

A process for producing a spectrally sensitized silver halide photographic emulsion is described, comprising adding a substantially water-insoluble spectral sensitizing dye in an aqueous carrier to an emulsion before completion of the formation of silver halide grains without using an organic solvent.

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Kanagawa, Japan

Hiroshi Ohnishi