The ink is formed by a solution of a direct dye in a mixture of water and glycol wetting agents, to which a pigment which is finely ground to particles of dimensions of not more than 1000 .ANG. is added in dispersion, in a concentration of between 0.1 and 2%. The pigment particles serve to anchor the gaseous nuclei of gases which are dissolved in the ink for the purpose of stabilizing the boiling point of the ink. The ink is particularly suited to an ink jet printer of the type in which expulsion of the droplets is produced by causing instantaneous vaporization of a portion of ink in a nozzle.
An ink jet apparatus is formed of a storing section for storing an electrically conductive ink, an electrode device formed in the storing section, and a nozzle. The conductive ink contains an electrically conductive liquid and an electrically conductive material having an electrical conductivity higher than that of the conductive liquid. The electrode device applies an alternating current to the conductive ink stored in the storing section to generate bubbles in the conductive liquid. The conductive ink is ejected through the nozzle due to generation of the bubbles by application of the alternating current.
An image formation apparatus includes a carriage for moving an ink jet recording head relatively with respect to a recording medium to discharge ink containing coloring materials in it from the ink discharge ports, means for applying to the recording medium the processing liquid that coheres the coloring materials in ink. This means for applying the processing liquid is arranged to be in contact with the recording medium and apply the processing liquid to the recording medium before ink to be discharged from the recording head of the ink jet recording head. This application means is mounted on the carriage. With such structure, images are formed on the recording medium, while the processing liquid and ink are caused to react upon each other thereon, thus obtaining the uniform images in good quality and condition.
An image forming apparatus includes a head mounting portion for mounting an ink jet recording head for discharging ink liquid having a coloring material from an ink discharge port. Also included is a process liquid storing member for storing a process liquid for condensing the coloring material in the ink liquid. A process liquid supply roller is arranged immersibly in the process liquid stored in the process liquid storing member. The process liquid supply roller does not contact a recording surface of the recording medium. A process liquid coating roller coats the recording surface with the process liquid supplied through the process liquid supply roller, the process liquid coating roller being provided so that a peripheral surface of the process liquid coating roller is contactable with the recording surface upstream of a conveyance direction of the recording medium with respect to the head mounting portion.
A process for applying an ink-jet printing ink comprising the steps of: (a) preparing an aqueous Newtonian dispersion containing acidic or neutral carbon black or pigments and a surfactant; (b) removing all aggregates larger than 5 microns; and (c) ink-jet printing said dispersion onto a receptor substrate.
A recording liquid comprises at least one of certain specified dyes carbon black, a water-soluble resin, a water-soluble organic solvent and water. The organic solvent includes polyhydric alcohol and/or its alkyl ether and an aliphatic monohydric alcohol. The water-soluble resin has an acid value of 50 to 300. The amount of the dissolved water-soluble resin is not more than 2% by weight. A method for ink jet recording comprises ejecting the recording liquid as liquid droplets from fine orifices by endowing the recording liquid with heat energy.
