Abstract: A solvent vapor fixing method is provided. Novel dry toner formulations for use with the method are also provided. The method and system of the invention may be advantageously utilized in color imaging, security document imaging, and magnetic ink character recognition printing within electrophotographic, electrographic, and magnetographic imaging systems designed for solvent vapor fixing.

Abstract: A compact fingerprinting system includes an applicator comprising a sealed packet (13) containing a porous pad (12) impregnated with a solution of water-soluble, color-forming, marking compound, such as iron chloride having a controlled, optimum water content. A print of a body part, such as a finger, is formed by opening the packet (60) and wiping the distal portion of a finger (76) on the pad (62), such as a folded towelette to form a non-visible, latent image pattern. The pattern is transferred to a card (40) which can contain an area (44) impregnated with developer for the marking compound. The developer reacts with the pattern to form a dark, distinct, permanent image (84). The card (40) and packet (13) can be enclosed in an envelope (64) to form a low profile, lightweight, mailable, self-administered fingerprinting system.

Abstract: Fingerprints images are formed by applying the distal portion 29 of a finger 32 to a porous pad 10 impregnated with a solution of marking compound. The finger portion may be prewetted or cleaned with cloth 30 impregnated with detergent solution. The finger 32 is then applied to a square 36 of a fingerprint card 38 impregnated with an aqueous solution of polyhydroxy developer such as 8-hydroxy-quinoline and propyl gallate containing a high molecular weight dibasic acid such as azelaic acid. A fingerprint image 40 immediately develops. Traces of the image can be removed with a cleaning solution impregnated cloth 42.

Abstract: Electrophotographic developer compositions containing carrier, toner and special purpose additives such as flow promoters, dry lubricants and the like are prepared by coating carrier particles with a coating selected so that the triboelectric relationship between the surface of the carrier and the surface of the additive is substantially zero.

Abstract: A free-flowing, non-spherical, fragmentary, toner particle is prepared by blending a mixture of thermoplastic resins with magnetic iron oxide. The dispersion is processed to a fine powder and dry blended with conductive carbon black which is anchored onto the surface of the particle by warm air or gas.

Abstract: Electrophotographic developer compositions containing carrier, toner and special purpose additives such as flow promoters, dry lubricants and the like are prepared by coating carrier particles with a coating selected so that the triboelectric relationship between the surface of the carrier and the surface of the additive is substantially zero.

Abstract: A free-flowing, non-spherical, fragmentary, toner particle is prepared by blending a mixture of thermoplastic resins with magnetic iron oxide. The dispersion is processed to a fine powder and dry blended with conductive carbon black which is anchored onto the surface of the particle by warm air or gas.

Abstract: Method and apparatus for recording sweat gland activity which provides a pictorial representation thereof by physical contact of an iodide treated skin area with a dry sensitized substrate. In one preferred embodiment, the sensitized substrate comprises a sheet material which has been coated with an aqueous solution containing from 1 to 10 percent by weight of starch and from 2 to 10 percent by weight of a suitable oxidizing agent such as potassium persulfate. Alternately, the dry sensitized substrate comprises a starch-oxidizing agent mixture which has been impregnated into an absorbent base layer. With slight modification of the foregoing embodiment, the present invention also provides a method and apparatus for obtaining inkless fingerprints by forming a sensitized coating in situ on a substrate. For fingerprinting purposes, the sensitized coating is preferably formed from a quick drying starch-oxidizing agent solution including alcohol as a solvent.

Abstract: A real-time laser recording film having a plastic/dye coating on one side thereof provides improved image sharpness and visual qualities. The film fabrication is compatible with continuous production techniques to provide an economical, high quality film.