Abstract: A method of gelation of a photographic emulsion, oil in water emulsion, or a gelatin-containing solution comprising continuously rapidly cooling the photographic emulsion, oil in water emulsion, or the gelatin-containing solution, which has good thermal efficiency and requires no adjustment of the amount of water contained in the rapidly cooled product prior to use, and a unit therefor comprising a static mixer-installed double pipe for rapidly cooling the photographic emulsion, oil in water emulsion, or the gelatin-containing solution by a conduction type heat exchange system, and a double pipe without static mixer for conveying the rapidly cooled product to a storage vessel while avoiding adhesion of the rapidly cooled product transformed into a gel state to the inside surface of the inner pipe of the double pipe by warming the inner pipe with water kept at 30.degree. C., although transformation of the rapidly cooled product to a gel state successively proceeds in an inner portion of the inner pipe.

Abstract: A flow control valve includes: an inlet casing concentric to a spindle; an outlet casing coupled with the inlet casing, an inlet portion of the outlet casing having a countersunk edge part; a head having two notches in the surface of a cylindrical portion, the head being put into the outlet casing; and a disk shaped as a truncated cone which is continuously provided to the head, the disk coming into contact with the countersunk edge part.