Abstract: A printing apparatus employing a bubble jet (a registered trademark) capable of maintaining at all times conditions of ink at and around a discharge port suitable for discharge without performing a predischarge or the like involving an interruption of a printing operation is provided. The printing apparatus supplies the electrothermal energy converting element with such an electrical energy that generates a bubble to the extent that ink droplets are discharged from the nozzle.

Abstract: A printing apparatus employing a bubble jet (a registered trademark) capable of maintaining at all times conditions of ink at and around a discharge port suitable for discharge without performing a predischarge or the like involving an interruption of a printing operation is provided. The printing apparatus supplies the electrothermal energy converting element with such an electrical energy that generates a bubble to the extent that ink droplets are discharged from the nozzle.

Abstract: In an inkjet recording apparatus, a head unit composed of a recording head and a ink tank is mounted on a carriage with an ejection port surface facing upward. The recording head records an image on a lower surface of a medium to be recorded by ejecting ink upward from ejecting ports. A preliminary ejection receiver is disposed outside of a region where an image can be recorded on the medium to be recorded to receive ink preliminarily ejected from the recording head in order to maintain and recover an ink ejection performance of the recording head. The preliminary ejection receiver has an opening acting an inlet for the preliminarily ejected ink. Further, a ceiling surface, which inclines with respect to a horizontal direction and on which the ink preliminarily ejected into the preliminary ejection receiver deposits, is disposed above the opening. With this arrangement, ink ejected into the preliminary ejection receiver is prevented from leaking from the opening.

Abstract: An ink supply mechanism, which is provided with an ink supply path to supply ink contained in an ink container to an ink jet recording head for recording images on a recording medium by discharging ink from discharge ports, comprises agitating means provided for the ink supply path for agitating ink flowing in the ink supply path. With the structure thus arranged, ink is supplied to the ink jet recording head in a state of being agitated by agitating means arranged in the ink supply path, thus making it possible to prevent the uneven concentrations of ink in an ink container left intact for a long time from appearing as the uneven densities of recorded images on a recording medium.

Abstract: The present invention relates to an ink set capable of achieving a further improvement in quality of an image formed on commercial plain paper. The ink set includes a combination of a recording performance improving liquid for improving the recording performance of ink jet ink, and ink jet ink for forming an image on a recording medium by an ink jet recording method, wherein the recording performance improving liquid contains at least cationic resin fine particles, the ink jet ink contains an organic pigment as a colorant, and the difference between the zeta potentials of the recording performance improving liquid and the ink jet ink is 30 mV or more.

Abstract: An ink supply mechanism, which is provided with an ink supply path to supply ink contained in an ink container to an ink jet recording head for recording images on a recording medium by discharging ink from discharge ports, comprises agitating means provided for the ink supply path for agitating ink flowing in the ink supply path. With the structure thus arranged, ink is supplied to the ink jet recording head in a state of being agitated by agitating means arranged in the ink supply path, thus making it possible to prevent the uneven concentrations of ink in an ink container left intact for a long time from appearing as the uneven densities of recorded images on a recording medium.

Abstract: Ink permeation with respect to paper differs in accordance with the temperature of the paper. As the temperature increases, the permeation increases, thus the ink immediately permeates into the paper as soon as it is attached to the paper. Accordingly, in a color ink-jet printer, upon printing, a portion in a print line of the paper is heated in accordance with control information corresponding to area designation information which is separate from print information. As ink quickly permeates at the heated portion, after printing with ink of a color, subsequent ink of another color does not mix with the previous color ink, thus bleeding can be prevented. Further, an area of character or the like is not heated, so that ink does not quickly permeate, thus feathering of outlines can be prevented.

Abstract: The ink jet recording apparatus of this invention comprises a means 67 for heating a record material to a predetermined temperature range at the position of recording, a recording head 41 for ejecting ink 46 from an ink ejection orifice 49 toward the record material to perform recording, the ink containing a substance having thickening properties when undergoing heat, and/or a substance having a cloud point for the heat; a means 69 for measuring the duration for which the recording head resides at the position of recording; and means for controlling the duration of residence in accordance with the properties of the ink to prevent the ejection function being impaired owing to the heating of the surroundings of the ink ejection orifice.

Abstract: Disclosed herein is a water-based ink for ink-jet, comprising a liquid composition containing a coloring material and a liquid medium, wherein the ink comprises a polymer exhibiting a heat-reversible type thickening property and a compound having a light-heat converting function, or a polymer which exhibits a heat-reversible type thickening property and has a moiety capable of undergoing light-heat conversion.

Abstract: In an inkjet recording apparatus, a head unit composed of a recording head and a ink tank is mounted on a carriage with an ejection port surface facing upward. The recording head records an image on a lower surface of a medium to be recorded by ejecting ink upward from ejecting ports. A preliminary ejection receiver is disposed outside of a region where an image can be recorded on the medium to be recorded to receive ink preliminarily ejected from the recording head in order to maintain and recover an ink ejection performance of the recording head. The preliminary ejection receiver has an opening acting an inlet for the preliminarily ejected ink. Further, a ceiling surface, which inclines with respect to a horizontal direction and on which the ink preliminarily ejected into the preliminary ejection receiver deposits, is disposed above the opening. With this arrangement, ink ejected into the preliminary ejection receiver is prevented from leaking from the opening.

Abstract: In control of a recording process in accordance with block driving, the driving timing of a pulse train is avoided from overlapping with each other between blocks, and a load imposed on a power supply during the operation is reduced. To that end, a recording apparatus includes a pulse generating unit for generating a driving pulse train consisted of a number (m) of pulses including a plurality of preheating pulses and one main driving pulse taking part directly in a recording process, the intervals between the (m) pulses being each not less than the total time of pulse widths of the (m) pulses, and a driving unit for dividing a plurality of recording elements into multiple blocks, and driving the recording elements in units of block to perform recording in such a manner that just before the second preheating pulse of the driving pulse train for one block, the first preheating pulse of the driving pulse train for the next block is applied.

Abstract: Ink permeation with respect to paper differs in accordance with the temperature of the paper. As the temperature increases, the permeation increass, thus the ink immediately permeates into the paper as soon as it is attached to the paper. Accordingly, in a color ink-jet printer, upon printing, a portion in a print line of the paper is heated in accordance with control information. As ink quickly permeates at the heated portion, after printing with ink of a color, subsequent ink of another color does not mix with the previous color ink, thus bleeding can be prevented. Further, an area of character or the like is not heated, so that ink does not quickly permeate, thus feathering of outlines can be prevented.

Abstract: The ink jet recording apparatus of this invention comprises a means 67 for heating a record material to a predetermined temperature range at the position of recording, a recording head 41 for ejecting ink 46 from an ink ejection orifice 49 toward the record material to perform recording, the ink containing a substance having thickening properties when undergoing heat, and/or a substance having a cloud point for the heat; a means 69 for measuring the duration for which the recording head resides at the position of recording; and means for controlling the duration of residence in accordance with the properties of the ink to prevent the ejection function being impaired owing to the heating of the surroundings of the ink ejection orifice.

Abstract: An ink container connectable with an ink inlet portion of an ink jet head having a plurality of ink ejection outlets, having an improvement in which a surface of the ink container to be connected with the ink jet head is inclined from a plane perpendicular to a direction in which the ink container is connected with the ink supply portion.

Abstract: The ink jet recording apparatus of this invention comprises a means 67 for heating a record material to a predetermined temperature range at the position of recording, a recording head 41 for ejecting ink 46 from an ink ejection orifice 49 toward the record material to perform recording, the ink containing a substance having thickening properties when undergoing heat, and/or a substance having a cloud point for the heat; a means 69 for measuring the duration for which the recording head resides at the position of recording; and means for controlling the duration of residence in accordance with the properties of the ink to prevent the ejection function being impaired owing to the heating of the surroundings of the ink ejection orifice.

Abstract: A liquid storing container employable for an ink jet recording apparatus includes a housing, a storing area containing a porous ink absorbing member, a valve mechanism, a filter in contact with the porous member, and a stopper. The liquid storing container is detachably connected to an ink jet recording head, where the valve mechanism allows an outflow of ink to the ink jet head through the joint portion when connected to an ink feed pipe, and closes the joint portion when disconnected from the ink feed pipe.

Abstract: A recording head includes a liquid ejecting outlet, a liquid passage communicating with the ejection outlet, and a heat generating resistor for supplying heat to the liquid in a heat acting portion in the liquid to create a bubble in the liquid passage to eject the liquid through the ejection outlet. A cross-sectional area of the liquid passage increases from the heat acting zone toward the ejection outlet, and this improves performance while also improving head durability.

Abstract: Provided is an ink-jet recording process comprising, using an ink containing a coloring matter, a liquid medium and at least one thermoreversible thickening polymer, ejecting the ink from orifices of a recording head onto a recording medium in accordance with recording signals to perform recording, wherein said ink is heated to various temperatures corresponding to recording image color signals to vary an optical density or a color reproduction range of a printed matter formed on a recording medium, thereby performing recording.

Abstract: Disclosed herein is a water-based ink for ink-jet, comprising a liquid composition containing a coloring material and a liquid medium, wherein the ink comprises a heat-reversible type thickening polymer.

Abstract: An ink-jet recording method comprises actuating a heating element which is in contact with an ink in a recording head, in response to a recording signal, to heat the ink thereby creating bubbles in the ink and thus ejecting ink droplets from the head so that recording is effected with the ink droplets. The ink is a liquid having a property such that its viscosity changes abruptly when heated and the heating element generates heat so that the average heat flux q.sub.o from the surface of the heating element to the ink satisfies the condition represented by the following formula: ##EQU1## where .kappa. denotes the coefficient of thermal conductivity of the ink, S the effective area of the heating element, V the volume of ink droplets ejected by one driving operation, T.sub.B the temperature of the ink at which bubbles are created in the ink, T.sub.o the temperature of the ink before the ink is ejected, T.sub.