Abstract: A color image forming method and apparatus using larger microcapsules each of which contains a plurality of kinds of smaller microcapsules scattered within the larger microcapsule, reacting substances that are mixed with each other to perform a coloring reaction being scattered inside and outside the smaller microcapsule. A protective wall of each smaller microcapsule is broken with a corresponding predetermined ultrasonic stimulus depending upon color component information to thereby cause the reacting substances to diffuse with each other to perform a coloring reaction and hence image printing. The conditions for breaking the protective walls of the respective smaller microcapsules that contain a color former component vary from smaller microcapsule to smaller microcapsule, or are determined depending upon the outer shapes, materials and thickness of the protective walls of the smaller microcapsules.

Abstract: Ink for use in an ink-jet color recording apparatus and a plurality of kinds of small microcapsules dispersed in the solvent, each small microcapsule having an outer shell destroyable with ultrasonic waves of a predetermined resonant frequency, each small microcapsule containing a color former within its outer shell with the outer surface of the outer shell covered with a developer. The plurality of kinds of small microcapsules are destroyed selectively with the corresponding predetermined stimuli to thereby produce magenta, cyan, yellow or black. The ink is colorless before producing the color. The ink-jet color recording apparatus irradiates the plurality of small microcapsules with ultrasonic waves of a selected frequency corresponding to a desired color to thereby change the color of the ink on a path through which the ink is fed from a color ink feeding device to an ink cartridge.

Abstract: A PC supplies previously compressed print data to a printer. In the printer, image data are generated based on the supplied print data, and the generated image data are developed in an image memory. Since the print data are compressed, a compressor/decompressor decompresses the print data. If available free area in the image memory is insufficient for developing the image data, the compressor/decompressor compresses the image data previously stored in the image memory, and the image memory is refreshed with the compressed image data. The compressed image data are decompressed by the compressor/decompressor before output to a printer engine. The compressor/decompressor is available for decompressing the print data during a period since the data reception from the PC until a sheet of paper onto which an image is formed reaches a predetermined position. When the sheet of the paper reaches the predetermined position, the compressor/decompressor is switched to decompress only the image data in the image memory.

Abstract: A color image forming method and apparatus using larger microcapsules each of which contains a plurality of kinds of smaller microcapsules scattered within the larger microcapsule, reacting substances that are mixed with each other to perform a coloring reaction being scattered inside and outside the smaller microcapsule. A protective wall of each smaller microcapsule is broken with a corresponding predetermined ultrasonic stimulus depending upon color component information to thereby cause the reacting substances to diffuse with each other to perform a coloring reaction and hence image printing. The conditions for breaking the protective walls of the respective smaller microcapsules that contain a color former component vary from smaller microcapsule to smaller microcapsule, or are determined depending upon the outer shapes, materials and thickness of the protective walls of the smaller microcapsules.

Abstract: Video data of yellow (Y), magenta (M), cyan (C) and black (K), stored in a DRAM, are transferred to an SRAM via a DMAC. The video data of yellow stored in the SRAM is transferred to a color printer engine by a DMAC for yellow. The video data of magenta stored in the SRAM is transferred to the color printer engine by a DMAC for magenta. The video data of cyan stored in the SRAM is transferred to the color printer engine by a DMAC for cyan. The video data of black stored in the SRAM is transferred to the color printer engine by a DMAC for black.

Abstract: An upper body which can be shifted from and toward a lower body through a link mechanism is formed. A drum unit and a toner unit are arranged on the side of the upper body. The upper body is opened in the parallel with respect to the lower body with a predetermined interval, by the link mechanism including arms. In the state where the upper body is opened, the drum unit and the toner unit can be detached from and attached to the printer device in frontward and backward directions, by sliding a sliding member arranged on the upper body.

Abstract: An identification label is affixed on a top surface of an image forming unit which is detachably installed in a main component of an image forming apparatus. The identification label is made of a thermosensitive paper on which a trademark logo is printed. A logo reader in the main component reads a pattern of the logo mark on the identification label. A control unit compares the read logo pattern with a previously stored pattern to discriminate whether the read logo mark is genuine or not. If the identification label has the genuine logo mark, the control unit executes printing. If the identification label has an irregular logo mark, printing is abandoned and an error message is displayed. When a genuine image forming unit is exhausted, the control unit controls a heating device to apply heat to the identification label in order to wholly or partially discolor the identification label so that the logo mark is transformed to unreadable one. That unit will be regarded as an irregular one thereafter.

Abstract: A head controller 2 reads out adjustment data from a ROM 3 immediately after a power-on operation. The adjustment data is prepared for adjusting unevenness of light emission from LEDs in a LED head 5. A buffer memory 4 stores the read adjustment data. The head controller 2 reads the adjustment data from the buffer memory 4 with high data transfer rate, and obtains bitmap data from a frame memory or the like (not shown). The head controller 2 sends the read bitmap data and the adjustment data to an anode driver 51. The head controller 2 sends a strobe signal to the anode driver 51 and a cathode driver 53. The anode driver 51 adjusts ampere of supplied currents (i.e. drive signals corresponding to the bitmap data) from the head controller 2, in accordance with the received adjustment data in response to the reception of the strobe signal. The adjusted drive signals are sent to LED array chips 52.

Abstract: A printer controller 41 sets compensation values, representing the positional deviations of LED array chips 31, in a delay circuit section 68 via shift register 61 and a latch circuit 63. The shift register 69 sequentially acquires bit map data from the printer controller 41, and supplies the acquired bit map data to an AND gate 66 through the latch circuit 62. Upon receiving a strobe signal from the printer controller 41, the delay circuit section 68 supplies the received strobe signal to the AND gate 66 after a delay time corresponding to a preset compensation value has lapsed. The AND gate 66 generates drive signals each being the logical product of the input bit map data and the strobe signal, and supplies them to the LED array chips 31 through a buffer 67. The LED array chips 31 make LEDs emit light at the timings corresponding to the positional deviations so that images are formed without a positional deviation.

Abstract: A ROM in the control circuit of a color printer stores a threshold matrix. The individual elements of the threshold matrix correspond to print dots, the number of which is X.times.Y and which form 1 pixel in the original image. Values t (x, y) which are integral numbers not less than 0 are assigned one to each of the individual elements in a predetermined order. Using the threshold matrix, the CPU of the control circuit creates mask patterns for representing halftones. A value of 1 is subtracted from the tone number allotted to the tone of color of a pixel in an image to be printed, and the resultant value is substituted for a variable G. When a gradation for image data representing the pixel is given as "g", the condition required for setting ON (transferring toner to print) the dot specified by the coordinates (x, y) in the pixel in the case of the gradation "g" is expressed by the following formula (6):t (x, y).ltoreq.g.times.X.times.

Abstract: A developing device used in an image forming apparatus has a developing roller at a lower opening of a toner hopper, and the developing roller contacts a photosensitive drum to form a developing portion therebetween. The hopper stores nonmagnetic toner and is provided with a toner stirring member and a toner feed roller being in press-contact with the developing roller in a lower part of the hopper. A doctor blade contacts a circumferential surface of the developing roller on an upstream side of the developing portion in a rotation direction of the drum. A conductive scooping sheet contacts the circumferential surface of the developing roller on a downstream side of the developing portion. A residual toner not used to develop a latent image on the drum and left on the developing roller is passed under the sheet into the hopper with the rotation of the developing roller.

Abstract: A form for printing print data, such as business data generated by an application program is generated by a form defining program. The form defining program designates a specific item (specific data item) in the form based on the predesignated print color of the form. A data discriminating section extracts data in a specific data item from the print data supplied from the application program. In accordance with the contents of the data in the specific data item, a color control command for changing the predesignated color of the form is generated. A printer controller change the color of the form in accordance with the color control command, supplied via a printer driver, and outputs the resultant data to a printing section. The printing section prints the print data in the color-changed form.

Abstract: A roller-shaped contact charging member which is in contact with and electrically charges a photosensitive drum is provided on a center shaft, and includes a roller-shaped conductive foam material portion covering the shaft, and a tubular-shaped conductive resin material portion covering the foam portion. The foam portion has an electric resistance of 9.times.10.sup.5 .OMEGA. or less, the resin portion includes conductive agents and has a surface electric resistance in a range from 1.times.10.sup.5 .OMEGA./.quadrature. or more to 9.times.10.sup.7 .OMEGA./.quadrature. or less, and a hardness of the charging roller as a whole is Asker F 90.degree. or less. An image forming unit includes the charging member and the drum. An electrophotographic image forming apparatus supplies a recording paper to the unit, transfers an image from the drum to the paper, and discharges the image-transferred paper.

Abstract: A motor starts its rotation, and a clutch is operated to drive both of a first driving force transmission system for color printing, including drum gears, and a second driving force transmission system for monochrome printing, including a drum gear. The clutch is disengaged to stop the first system when a first sensor detects a mark on one photosensitive drum of the first system at the same time that a second sensor detects a mark on one drum driving gear of the first system. Next, when a third sensor detects a mark on another photosensitive drum of the second system at the same time that a fourth sensor detects a mark on another drum driving gear of the second system, the clutch is reengaged. Consequently, positionings of all the photosensitive body drums (drum gears) for color printing to the photosensitive drum (drum gear) for monochrome printing are performed without causing positional differences by inertia at the time of stop.

Abstract: Defining information for defining the condition for adding background colors is previously stored in a condition storage area, and a spreadsheet form is registered in a form storage area. Alphanumeric character data to be written in a cell of a spreadsheet are stored in a record storage area. When a CPU is instructed to start printing, the CPU outputs the alphanumeric character data as output data to a data value decision section. The data value decision section reads the output data and determines a background color in accordance with the read output data to prepare a print record to which color information is added. A printer control section prepares print data to which the background color is added in accordance with the color information for the print record and the spreadsheet form registered in the form storage area.

Abstract: An apparatus for cleaning an endless belt, on both side end portions of the inner peripheral surface of which a pair of belt-shaped side stoppers are provided, includes a blade pressed against the outer peripheral surface of the belt and a backup roller. At both side end surfaces of the roller, assistant support rollers are provided to support the both side stoppers to prevent the both side end portions of the belt from moving inward to separate from the blade by a pressure applied from the blade. An image forming apparatus having such a belt cleaning apparatus includes a plurality of image carrying bodies arranged side by side along the belt, a plurality of toner image developer for developing images on the carrying bodies by toner, and a plurality of transfer units for transferring the developed toner images on the image carrying bodies to a paper sheet transferred by the belt.

Abstract: An image forming apparatus has four color image forming and transferring portions and four image writing heads supported by a cover to be rotatably movable upwardly and downwardly. Each case of the portions is so shaped that it does not interfere with the rotational movement of the heads, and has the same shape. Particularly, two opposite side surfaces of the case is so shaped that it does not project into the movement locuses of the heads not to collide them.