Abstract: A thermal recording apparatus operates to efficiently utilize a smaller capacity power supply by the provision of a capacitor in parallel with the power supply source. The capacitor is discharged during printing cycles and is recharged in the interval between the end of one line printing operation and the beginning of the next. This interval is increased in proportion to the percentage of black bits printed in a given line, such that the capacitor may be sufficiently charged and the power supply efficiently used.

Abstract: A thermal head drive circuit with the input connected to a source of printing data and the output connected to a thermal head including heater elements, so as to improve the printing quality of a thermal head recording apparatus for printing successive lines. Improved printing quality is effected by using data from previously printed lines to compute a corrected pulse energy for the line being printed. The circuit uses a heat accumulation state operator for computing the heat storage state of each of the heater elements constituting a thermal head, a pulse energy operator for computing a printing pulse energy to be applied to each of the heater elements, a memory for storing the electrical pulse energy used in the previously printed line, and either a pulse interval detector for detecting a time interval from a termination of printing of a previously printed line, or a temperature detector for detecting an internal-temperature of a thermal head.

Abstract: A thermal head is provided with a plurality of juxtaposed heat generating resistors for applying heat to heat sensitive printing medium for reproducing a picture. The resistance values of the heat generating resistors are individually detected at predetermined times and used to update the contents of a memory means. An arithmetic operating circuit calculates quantities of electric power to be supplied to respective heat generating resistors for causing them to generate the same quantity of heat irrespective of the difference in the resistance values of the heat generating resistors.

Abstract: A thermal head drive circuit with the input connected to a source of printing data and the output connected to a thermal head including heater elements, so as to improve the picture quality of a thermal head recording apparatus for printing successive lines. Improved picture quality is effected by using data from previously printed lines to compute a corrected pulse energy for the line being printed. The circuit uses a heat storage state operator for operating the heat storage state of each of the heater elements constituting a thermal head, a pulse energy operator for computing a printing pulse energy to be applied to each of the heater elements, a memory for storing the electrical pulse energy used in the previously printed line, and a counter to count the number of dots on the line to be printed. The pulse energy operator uses data from the heat storage state operator, the counter, and from the memory which has data on the pulse energy used in previously printed lines.

Abstract: A transfer type heat sensitive recording medium includes a base member and an ink layer formed thereon of a colored ink which is adapted to be fluidized or sublimated at a predetermined temperature higher than room temperature. The surface of the ink layer is covered with a coating layer of a coating material which is adapted to be dissolved into the ink layer or sublimated when heated at a temperature higher than a predetermined temperature.

Abstract: A thermal head is provided with first and second sets of parallel bar-shaped electrodes which are arranged in slightly spaced parallel planes and cross over one another. Individual crossing resistors are selectively energized to produce a heat generating dot which may be reproduced on a heat sensitive media.

Abstract: A heat-sensitive recording head, comprising:two heat generating resistors which are obtained by dividing a conventional heat generating resistor, the resistors being arranged substantially in parallel with each other on a substrate; andfirst and second groups of lead electrodes which are coupled to the two heat generating resistors, respectively, in such a manner that the first and second groups of lead electrodes are shifted by half a pitch from each other.

Abstract: A two-color copying machine includes a scanner unit for producing output signals representing different colors of an original image and a thermal printer heating its heating elements to temperature ranges in accordance with the scanner unit output signals and utilizing a recording medium which records in two different colors depending on the applied temperature.

Abstract: A heat sensitive recording apparatus using an ink donor sheet in the form of a continuous band includes a device for detecting and correcting the tension applied to the band so as to prevent creases, etc. from being formed therein.

Abstract: An ink donor sheet recording medium is disclosed. The medium is comprised of a paper base which has a solidified ink layer formed on one surface. The paper base is rendered moisture proof by providing a dampproof layer on the surface opposite the ink layer or by incorporating a hydrophobic compound within the paper. By rendering the medium moisture proof the medium can be used under adverse humidity conditions without being physically distorted. Accordingly, the medium can form clear sharp images even when used in adverse humidity conditions.

Abstract: A heat-sensitive transfer type recording device is provided with a thermal head having heat generating elements and a backing roll operatively positioned relative to the heat generating elements to accommodate the passage of an ink donor sheet and a recording sheet therebetween under pressure. A separation roll is spaced from the backing roll to provide for the passage of said ink donor sheet and said recording sheet therebetween at a pressure substantially less than the pressure exerted on the sheets upon passage between the backing roll and the heat generating elements. The ink donor sheet is directed about the separation roll at a relatively sharp angle to separate the recording sheet from the ink donor sheet with a complete transfer of the ink from the ink donor sheet to the recording sheet as a result of the reduced pressure on the sheets at the separation roll.

Abstract: A thermal head driving method in which serial picture data to be recorded on one line is inputted into a shift register which produces parallel picture data corresponding to the input series picture data to drive heating elements of a thermal head by the parallel picture data. The method comprises the steps of inputting serial picture data into the shift register and a distinguishment data element is added in front of the serial picture data. A timing determination of when a predetermined amount of picture data to be simultaneously recorded have been set in the shift register is made on the basis of a timing when the distinguishment data element is outputted from an output terminal through which the serial picture data is outputted. The thermal head is driven while stopping input of a serial picture data into the shift register, at the first-mentioned timing.

Abstract: An ink donor sheet comprising a porous sheet and a heat-fusible ink layer formed on it is disclosed. The ink layer has such temperature-dependent gradation characteristics that it remains solid at ordinary temperatures and when it is heated to a certain temperature its viscosity is suddenly decreased and upon further heating, the viscosity is decreased gradually. The ink donor sheet is capable of producing halftones in the images it creates.

Abstract: A heat transfer recording medium which comprises tissue paper having thereon an ink layer comprised of material fluidizable or sublimatable upon the application of heat. The tissue paper has a thickness of 5 to 25 .mu.m, a density of 0.8 to 1.45 g/cm.sup.3, a smoothness of 200 to 20,000 seconds (determined by the Oken type measurement) and a water content adjusted to 6 to 13 wt % after forming the ink layer thereon. The medium does not generate puckers when employed in a transfer type heat sensitive recording apparatus under high temperature and humidity conditions.

Abstract: A thermal head driving system having a plurality of thermal heads, an electric power source commonly used to drive the heads at the same voltage. A pulse generator provided between the power source and each of the heads for producing a driving pulse having a width determined in accordance with a ratio of a resistance value of each thermal head. The plurality of thermal heads are accordingly driven by the respective driving pulses corresponding thereto to effectuate thermal recording.

Abstract: A heat-sensitive recording apparatus includes a two-stage buffer memory for storing input video signals corresponding to one line, and a counter which determines the proportion of "black" signals in one line as the signals are input thereto. Whether printing of the line is to be carried out in one or plural operations is determined by the determined proportion, and a signal indicative of the number of operations is outputted to a block driver prior to the time when the corresponding video signals are outputted by the second stage of the buffer memory to a shift register.

Abstract: A thermal recording method which prevents recording density defects includes preheating the heating elements of the thermal recording head during a time when printing is not carried out. Particularly, the head may be preheated during times when a line is not printed, as between adjacent character lines of a printed or typed document, to prevent recording density deterioration of the next printed line.

Abstract: A copying machine includes an optical sensor of the line scanning type for converting an image into electrical signals, and a thermal recording head controlled in accordance with the image signals. The platen moves with respect to the read unit and the read unit will read in both forward and reverse directions of the platen, and the magnification value can be varied. The total width of energized heating elements and the movement length and speed of the platen may be controlled in accordance with the size of the original. The total number of heating elements energized at any one time is limited, and the machine includes input and output terminals for sending image information externally and for receiving and recording image information other than directly from the read unit.

Abstract: A copying machine includes an optical sensor of the line scanning type for converting an image into electrical signals, and a thermal recording head controlled in accordance with the image signals. Either the platen or read unit are movable and the read unit will read in both forward and reverse directions of movement, and the magnification value can also be varied. The total width of energized heating elements and the movement length of the read unit or platen may be controlled in accordance with the size of the original. The total number of heating elements energized at any one time is limited, and the machine includes input and output terminals for sending image information externally and for receiving and recording image information other than directly from the read unit. A cutter is provided for cutting the recording paper web immediately prior to discharge.

Abstract: The adjustment of pressure between the thermal head assembly and back roll in a thermal recording device is achieved by adjusting the bias force applied to the thermal head rather than the back roll, to thereby maintain a substantially constant contact pressure between the back roll and a drive roll.