Abstract: [Problem]: An optical recording medium having a capability of recording and/or reading high density optical information using a short wavelength laser light is provided. [Means to Address the Problem]: The optical recording medium has a capability of recording and/or reading high density optical information using a short wavelength laser light having a wavelength of 350 nm to 530 nm. The optical recording medium has a recording layer containing a metal complex compound and formed on a substrate. The metal complex compound is composed of a cyclic ?-diketone azo compound represented by the general formula (I) or general formula (II) and a divalent metal ion coordinated to the cyclic ?-diketone azo compound.

Abstract: An actuator can selectively take a first state wherein a volume of a pressure chamber is V1 and a second state wherein the volume of the pressure chamber is V2 larger than V1. The actuator changes from the first state to the second state and then returns to the first state to eject ink from an ejection port. A proper oscillation period Ts of an oscillation generated by integral deformation of the actuator and the pressure chamber when ink is ejected from the ejection port, and a proper oscillation period Td of ink filling up a first partial passage leading from an outlet of the pressure chamber to the ejection port in an individual ink passage, satisfy a condition that Ts/Td is not less than 0.36 and not more than 0.90; or not less than 1.1 and not more than 1.7.

Abstract: The azo-metal chelate dye to which the present invention is applied is a compound formed as follows: for example, 1,3,4-thiadiazole ring is selected as the diazo component; the diazo component is combined with a coupler component having condensed rings including a fluorine-substituted alkylsulfonylamino group and an amino group, to form an azo dye compound; and the azo dye compound forms chelate bonds with at least one metal selected from the group consisting of Co, Ni, Cu and Pd. Here, two absorption bands (OD1 and OD2) are seen in the absorption spectrum, which is measured in a range of 400 to 800 nm wavelengths. The azo-metal chelate dye is characterized in that the optical density ratio (OD2/OD1) of the two absorption bands is greater than 1.25. By using this azo-metal chelate dye, an optical recording medium capable of high-speed recording is provided.

Abstract: The present invention has an object to widen the range of applicable field of organic compounds to be selected as light absorbing materials in various fields including information recordings, solar energy generations, electric machinery apparatuses, electric communicating apparatuses, optical apparatuses, clothes, building/bedding/decorating products, sanitary and health goods, and agricultural materials, particularly, in the field of optical recording media by providing novel organic materials which absorb short-wavelength visible light, have improved lightfastness and solubility in solvents, and also have heat characteristics depending upon uses to be applied. The object is attained by providing cyanine dyes having a specific structure.

Abstract: The present invention teaches and claims an image forming apparatus comprising: an image forming portion including one or more inkjet heads for forming an image on a recording medium by discharging ink from an ink discharge surface of the inkjet head; a recording medium transporting portion having a transport surface which is positioned below the ink discharge surface and on which the recording medium is placed for transporting a sheet to a position facing the ink discharge surface; a moving mechanism for moving the transport surface toward and away from the ink discharge surface; an ink discharge surface protecting mechanism including but not limited to a cap member and a driving device for moving the cap member; and a control unit for moving the transport surface away from the ink discharge surface to operate the ink discharge surface protecting mechanism when the recording medium is jammed during transportation of the recording medium.

Abstract: The azo-metal chelate dye of the present invention is formed, for example, from zinc (divalent) as a center metal ion and an azo compound bonded with a coupler component having an amino group and a fluorine-substituted alkylsulfonylamino group subjected to condensed ring-formation to have a 1,3,4-thiazole ring as a diazo component.

Abstract: The present invention provides a method for driving a piezoelectric ink jet head that surely suppresses the ensuing vibration of the drive section while suppressing the flying speed of the ink droplet from decreasing, by setting the time constant ?UP of rise of voltage when the drive voltage is applied and/or the time constant ?DN of fall of voltage when stopping the application of the drive voltage are set in ranges that satisfy the relations of the expressions (i) and (ii): Ta/(?ln 0.01)??UP?Ta/(?ln 0.25) ??(i) Ta/(?ln 0.01)??DN?Ta/(?ln 0.25) ??(ii) with respect to the period Ta of the ensuing vibration of the drive section, or pulse width T3 of the drive voltage is set at an integral multiple of the period Ta of the ensuing vibration of the drive section.

Abstract: The present invention is directed to a method for driving a piezoelectric ink jet head comprising a piezoelectric actuator AC that includes two piezoelectric ceramic layers 7a, 7b having such a size that covers the plurality of pressure chambers 2, wherein an electric field of opposite sense to the polarizing direction is applied to the second piezoelectric ceramic layer 7b by using the common electrodes 8a, 8b and, (1) for the pressure chambers 2 from which the ink is discharged, an electric field of the same sense as the polarizing direction of the layer is applied to the first piezoelectric ceramic layer 7a by using the individual electrode 10 and the first common electrode 8a, thereby causing the region of the piezoelectric actuator AC to deflect toward the pressure chamber 2, while (2) for the pressure chambers 2 from which the ink should not be discharged, an electric field of the opposite sense to the polarizing direction is applied to the first piezoelectric ceramic layer 7a by using the electrodes 10

Abstract: An object of the present invention is to inhibit a decrease in cleaning efficiency when the amount of ink discharged from the ink discharge portion is increased. A method of cleaning an ink discharge portion of an inkjet printer includes a scraping-away-ink step, a cleaning step with water, and scraping-away-fluid step. The inkjet printer includes the ink discharge portion that is formed to extend in a direction and includes an ink discharge surface being capable of discharging ink. The inkjet printer is also capable of forming an image on media by discharging the ink on the media by way of the ink discharge portion. Here, the scraping-away-ink step is a step of scraping away the ink adhering to the surface of the ink discharge portion. The cleaning step with water is a step of cleaning the surface of the ink discharge portion with water.

Abstract: The present invention provides a method for driving a piezoelectric ink jet head that surely suppresses the ensuing vibration of the drive section while suppressing the flying speed of the ink droplet from decreasing, by setting the time constant ?UP of rise of voltage when the drive voltage is applied and/or the time constant ?DN of fall of voltage when stopping the application of the drive voltage are set in ranges that satisfy the relations of the expressions (i) and (ii): Ta/(?ln 0.01)??UP?Ta/(?ln 0.25) ??(i) Ta/(?ln 0.01)??DN?Ta/(?ln 0.25) ??(ii) with respect to the period Ta of the ensuing vibration of the drive section, or pulse width T3 of the drive voltage is set at an integral multiple of the period Ta of the ensuing vibration of the drive section.

Abstract: An actuator can selectively switch a volume of a pressure chamber between a first state V1 and a second state V2, which is greater than V1. The actuator changes from the first state into the second state and then changes back into the first state to eject ink from an ejection port. A controller controls the actuator such that To/Tc falls within a range from 0.51 to 0.54. To represents the time period between time the actuator starts to change from the first state into the second state, to a time the actuator starts to change from the second state into the first state. Tc represents the period of proper oscillation of ink filling up the individual ink passage. The actuator is controlled so that a variation in ink ejection speed is prevented from being too large relative to the variation in the degree of deformation of the actuator.

Abstract: An inkjet head includes a passage unit and an actuator unit. The passage unit includes a common ink chamber and an individual ink passage leading from an outlet of the common ink chamber through a pressure chamber to an ejection port. The actuator unit can selectively take a first state in which the volume of the pressure chamber is V1 and a second state in which the volume of the pressure chamber is V2 larger than V1. The actuator unit changes from the first state into the second state and then returns to the first state to eject ink from the ejection port. The individual ink passage is formed such that the volume Vd of a partial passage in the individual ink passage corresponding to a region from an outlet of the pressure chamber to the ejection port, and the volume Vc of the individual ink passage, satisfy a condition that Vd/Vc is not less than 0.12 and not more than 0.40.

Abstract: An actuator can selectively take a first state wherein a volume of a pressure chamber is V1 and a second state wherein the volume of the pressure chamber is V2 larger than V1. The actuator changes from the first state to the second state and then returns to the first state to eject ink from an ejection port. A proper oscillation period Ts of an oscillation generated by integral deformation of the actuator and the pressure chamber when ink is ejected from the ejection port, and a proper oscillation period Td of ink filling up a first partial passage leading from an outlet of the pressure chamber to the ejection port in an individual ink passage, satisfy a condition that Ts/Td is not less than 0.36 and not more than 0.90; or not less then 1.1 and not more than 1.7.

Abstract: The present invention is directed to a piezoelectric ink jet head wherein contacts for the electrical connection of the upper and lower electrodes that sandwich the piezoelectric element on the upper and lower sides are disposed in a solid region of the substrate where any of recess to make the pressure cavity, common feed path, feed port, nozzle passage or nozzle is not formed, in order to surely prevent the vibration characteristic of individual drive regions or individual piezoelectric element from varying.

Abstract: A controller controls a pressurizing actuator in such a manner that a pressure chamber changes from a first state where a volume of the pressure chamber is V1 to a second state where the volume is V2 larger than V1 and then returns from the second to the first state to cause ink to be ejected from an ejection opening, that a time length Tv1 from a time point at which the pressure chamber starts to change from the first to the second state to a time point at which the pressure chamber is in the second state becomes 33% or more of a characteristic vibration period Td of ink filled in a first ink passage extending from an outlet of the pressure chamber to the ejection opening, and that the time length Tv1 becomes 83% or less of the characteristic vibration period Td.

Abstract: The azo-metal chelate dye of the present invention is formed, for example, from zinc (divalent) as a center metal ion and an azo compound bonded with a coupler component having an amino group and a fluorine-substituted alkylsulfonylamino group subjected to condensed ring-formation to have a 1,3,4-thiazole ring as a diazo component.

Abstract: The present invention is directed to a method for driving a piezoelectric ink jet head comprising a piezoelectric actuator AC that includes two piezoelectric ceramic layers 7a, 7b having such a size that covers the plurality of pressure chambers 2, wherein an electric field of opposite sense to the polarizing direction is applied to the second piezoelectric ceramic layer 7b by using the common electrodes 8a, 8b and, (1) for the pressure chambers 2 from which the ink is discharged, an electric field of the same sense as the polarizing direction of the layer is applied to the first piezoelectric ceramic layer 7a by using the individual electrode 10 and the first common electrode 8a, thereby causing the region of the piezoelectric actuator AC to deflect toward the pressure chamber 2, while (2) for the pressure chambers 2 from which the ink should not be discharged, an electric field of the opposite sense to the polarizing direction is applied to the first piezoelectric ceramic layer 7a by using the electrodes 10

Abstract: The present invention provides a method for driving a piezoelectric ink jet head that surely suppresses the ensuing vibration of the drive section while suppressing the flying speed of the ink droplet from decreasing, by setting the time constant ?UP of rise of voltage when the drive voltage is applied and/or the time constant ?DN of fall of voltage when stopping the application of the drive voltage are set in ranges that satisfy the relations of the expressions (i) and (ii): Ta/(?ln 0.01)??UP?Ta/(?ln 0.25)??(i) Ta/(?ln 0.01)??DN?Ta/(?ln 0.25)??(ii) with respect to the period Ta of the ensuing vibration of the drive section, or pulse width T3 of the drive voltage is set at an integral multiple of the period Ta of the ensuing vibration of the drive section.

Abstract: The present invention provides a method for driving a piezoelectric ink jet head that surely suppresses the ensuing vibration of the drive section while suppressing the flying speed of the ink droplet from decreasing, by setting the time constant ?UP of rise of voltage when the drive voltage is applied and/or the time constant ?DN of fall of voltage when stopping the application of the drive voltage are set in ranges that satisfy the relations of the expressions (i) and (ii): Ta/(?ln 0.01)??UP?Ta/(?ln 0.25) ??(i) Ta/(?ln 0.01)??DN?Ta/(?ln 0.

Abstract: The present invention is directed to a method for driving a piezoelectric ink jet head comprising a piezoelectric actuator AC that includes two piezoelectric ceramic layers 7a, 7b having such a size that covers the plurality of pressure chambers 2, wherein an electric field of opposite sense to the polarizing direction is applied to the second piezoelectric ceramic layer 7b by using the common electrodes 8a, 8b and, (1) for the pressure chambers 2 from which the ink is discharged, an electric field of the same sense as the polarizing direction of the layer is applied to the first piezoelectric ceramic layer 7a by using the individual electrode 10 and the first common electrode 8a, thereby causing the region of the piezoelectric actuator AC to deflect toward the pressure chamber 2, while (2) for the pressure chambers 2 from which the ink should not be discharged, an electric field of the opposite sense to the polarizing direction is applied to the first piezoelectric ceramic layer 7a by using the electrodes 10