JP2006168315A - Ink-jet recording head and ink-jet recording method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet recording head and an ink-jet recording method which can realize the improvement of a heater board shrink and a BJ head throughput. <P>SOLUTION: In the BJ head for performing a time-sharing driving, a nozzle sequential selection means for sequentially selecting the driving nozzle according to a clock signal input from outside is composed inside the head. Apart from the nozzle sequential selection means, an adjoining nozzle selection means for non-ejection correction is composed. The ink-jet recording method using the above-mentioned composition is provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording head and an ink jet recording method for discharging a desired liquid by applying energy from the outside to the liquid.

  With respect to this type of ink jet recording head, for example, the ink jet recording method described in Patent Document 1 is different from other ink jet recording methods in that thermal energy is applied to a liquid to obtain a driving force for droplet ejection. It has characteristics. That is, in the recording method disclosed in Patent Document 1 described above, the liquid that has been subjected to the action of thermal energy is heated to generate bubbles, and the action force based on the generation of the bubbles causes the liquid from the orifice at the tip of the recording head unit. It is characterized in that droplets are formed and the droplets adhere to the recording member to record information.

  A recording head applied to this recording method generally includes an orifice provided for ejecting a liquid, and a heat acting portion that is a portion where heat energy for ejecting droplets communicated with the orifice acts on the liquid. A liquid discharge portion having a liquid flow path having a liquid crystal structure as a part, a heat generation resistance layer as a heat conversion body which is a means for generating thermal energy, an upper protective layer for protecting it from ink, and a lower layer for storing heat It has.

  In recent years, in order to realize high-definition image recording at a higher speed, there has been a demand for a printing width wider and a higher orifice arrangement density. A conventional example will be described with reference to FIGS.

  FIG. 8 is an external perspective view showing an example of a conventional ink jet recording head, FIG. 9 is a schematic perspective view schematically showing a cross section of the main part, and FIGS. 10 to 13 show the driving method and recording paper. It is a figure for demonstrating the recording method.

  In this ink jet recording head, a heater 111 is provided on a silicon substrate 101, and nozzles are formed by a nozzle material (not shown). Ink is supplied from the back surface of the silicon substrate 101 through an ink supply port 110 formed as a hole penetrating the silicon substrate 101. By applying electric energy to the heater 111 to heat and foam the ink, the ink is ejected from the ejection port 102 and recording is performed.

  Electric energy is applied to the heater 111 by a built-in driving element 103 provided on the silicon substrate 101 through the electric circuit board 107 and the flexible circuit board 105 in accordance with a signal input from the outside through the electric connector 108. Is called. As methods for forming high-density, high-precision nozzles and ejection openings in such an ink jet recording head, methods disclosed in Patent Document 2 and Patent Document 3 have been proposed.

  The most common conventional example of such an ink jet recording head drive circuit will be described with reference to FIG.

  A driver transistor 601 is provided corresponding to each heater 111, and the driver transistor 601 is driven in accordance with print data, a time-division drive signal, and an ejection pulse input from the outside of the head, and ink is ejected.

  In the circuit shown in FIG. 10, a 1-bit shift register 604 and a latch register 605 are provided corresponding to each heater 111, and print data is shifted in synchronization with the clock signal from Data1 in FIG. The signals are sequentially input to the register 604 and stored in the latch register 605 together with the input of the latch signal. The decoder circuit 606 is driven in accordance with a decoder input signal input from the outside, and the data stored in the latch register 605 is sequentially selected in a time-sharing manner, and the AND circuit 603 and driver are applied together with the application of the ejection pulse signal (ENB). The transistor 601 is driven.

  For such a configuration, a drive circuit as shown in FIG. 11 is also known for the purpose of reducing the number of data lines of the decoder input signal.

  In the drive circuit shown in FIG. 11, a decoder input signal input to a decoder circuit 606 for performing time-division driving is input from a decoder input data storage shift register 607 and a decoder input data storage latch register 608. The decoder input data storage shift register 607 has a signal line connected in cascade with the shift register 604 for storing print data.

  In order to perform high-speed printing with such an ink jet recording head, a large number of ink ejection openings 102 are formed side by side across the width of the recording paper, and all the recording paper is scanned once relative to the ink jet recording head. A method for recording print data is known.

  In such an ink jet recording head, if any one of the many nozzles is defective, it will lead to defective printing. Therefore, even if there are defective nozzles, other nozzles are used to compensate for defective printing. The method of doing is known conventionally. This method will be described with reference to FIGS.

  FIG. 13 shows a first example of a conventionally known method for complementing printing defects in an inkjet recording head having a partially defective nozzle. This figure is a diagram when a pattern of 100% print duty is printed. In the drawing, an ink jet recording head is arranged in the X direction, and printing is performed while scanning in the Y direction. Originally, when a print pattern as shown in FIG. 13A is formed, but there is a nozzle that cannot eject ink due to some trouble, white stripes are formed as shown in FIG. 13B.

In order to compensate for this, as shown in FIG. 13C, there is a method in which the nozzle adjacent to the non-ejection nozzle ejects at a frequency twice the original recording density and ejects the non-ejection nozzle complementary dot 503. Are known. As an example of the flying ink droplet when such complementary driving is performed, there is a problem in the nozzle with nozzle number 507, and an example in which complementary ejection is performed with the nozzle with nozzle number 508 is shown in FIG.
JP 54-51837 A JP-A-5-330066 JP-A-6-286149

  However, the conventional ink jet recording head and recording method as described above have the following problems.

  First, in the circuit configuration shown in FIG. 10, with the use of other nozzles in the head, the input signal of the decoder circuit 606 increases, leading to an increase in the number of signal electrodes taken out from the silicon substrate 101. As a result, the silicon substrate As a result, the size of the ink jet recording head is increased.

  In the circuit configuration shown in FIG. 11, although the number of extraction signal electrodes can be kept low, it is necessary to input all the data corresponding to the decoder input signal in addition to the print data as serial data for each temporary division drive in addition to the print data. The amount of data was increasing. As a result, the time required for each temporarily divided drive is accelerated by the data transfer time, and the drive frequency of the ink jet recording head has to be lowered, which in turn causes a decrease in the throughput of the ink jet recording head.

  The present invention has been made paying attention to the above points, and provides an ink jet recording head and an ink jet recording method capable of performing complementary printing of defective nozzles with almost no sacrifice in printing time. For the purpose.

  The present invention solves the above-described problems in an ink jet recording head in which a large number of nozzles are arranged in a row and the nozzles are driven in a time-sharing manner. The summary is described below.

A first aspect of the present invention is an ink jet recording head having a plurality of nozzles for forming an image on a recording medium,
Having time-division driving means for driving each of the nozzles in a time-division manner;
The time-division driving means is present in an ink jet recording head having nozzle sequential selection means for sequentially selecting nozzles to be driven in a desired order in accordance with a clock signal input from the outside.

  According to a second aspect of the present invention, the nozzle sequential selecting means selects a counter circuit that outputs a binary signal in accordance with a clock signal input from the outside, and a driving nozzle in accordance with an output signal of the counter circuit. The inkjet recording head according to the first aspect is characterized by having a decoder circuit.

According to a third aspect of the present invention, the time-division driving means is
The nozzle sequential selection means;
An individual nozzle selecting means capable of individually and electrically selecting an arbitrary nozzle in accordance with a nozzle selection signal input from the outside;
The inkjet recording according to the first or second aspect, further comprising: a nozzle selection signal selection unit that selects which of the signals of the nozzle sequential selection unit and the individual nozzle selection unit is to be activated. Present in the head.

A fourth aspect of the present invention is a recording method for an ink jet recording head that forms an image by ejecting ink in accordance with an image signal input from the outside while scanning once relative to the recording medium. There,
The inkjet recording head includes a plurality of nozzles at a pitch corresponding to an image recording density in the nozzle row direction in a nozzle row direction perpendicular to a scanning direction for scanning the inkjet recording head with respect to the recording material. Is formed,
An inkjet recording method for performing recording by driving the plurality of nozzles divided into a plurality of timings dispersed in time within an image recording density unit in the scanning direction,
The inkjet recording head has a nozzle group unit that is divided and driven at different timings within the image recording density unit among the plurality of nozzles, and the nozzles in the nozzle group unit , An ink jet recording method for electrical selection by the nozzle sequential selection step,
When the nozzle group unit has a normal nozzle that can eject ink and a defective nozzle that cannot eject ink, the normal nozzle corresponding to the pixel adjacent to the defective nozzle in the nozzle row direction is the defect. An inkjet recording method that performs dot complementation of the defective nozzle by driving in response to an image signal corresponding to a nozzle,
In the ink jet recording method, the defective nozzle is complemented by selecting a normal nozzle corresponding to a pixel adjacent to the defective nozzle in the nozzle row direction by the nozzle individual selection step.

  The present invention does not directly input the input data of the decoder circuit from the outside of the head, but uses a counter circuit, thereby reducing the number of signal input terminals from the outside, realizing a reduction in size of the silicon substrate 101, and thus an inexpensive inkjet. A recording head is provided.

  Further, by providing signal input means to a decoder circuit of a system different from the signal from the counter circuit, it is possible to perform complementary printing of defective nozzles with almost no sacrifice of the printing time of the ink jet recording head. An ink jet recording head and an ink jet recording method are provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to examples.

  1 to 4 are diagrams for explaining a first embodiment of the present invention. FIG. 1 is a block diagram of a drive circuit for an ink jet recording head according to a first embodiment of the present invention, FIG. 2 is an external perspective view of the ink jet recording head for implementing the ink jet recording method of the present invention, and FIG. FIG. 4 is a sectional perspective view of the main part of the ink jet recording head.

  In the ink jet recording head for carrying out the present invention, two rows of 2048 heaters 111 are provided on a silicon substrate 101 at a pitch of 600 dpi, and nozzles are formed corresponding to each of the heaters 111 using a nozzle material. Ink is supplied from the ink common liquid chamber 117 formed in the support member 106 through the base plate 104 to the heater 111 from the back surface of the silicon substrate 101 through the ink supply port 110 formed as a hole penetrating the silicon substrate 101. Is done.

  These configurations are substantially symmetrical with respect to the ink supply port 110, and the two rows of heaters 111 are shifted from each other by a half pitch, and by using the two rows of heaters 111 together, 1200 dpi. The print density is realized.

  The ink supply port 110 may be formed by using a silicon substrate 101 having a plane orientation of (100) and using a silicon anisotropic etching method, or by forming the silicon substrate 101 by machining. However, in this embodiment, the silicon substrate is formed by performing anisotropic etching.

  Printing is performed by applying electric energy to the heater 111 to heat and foam the ink, thereby discharging the ink from the discharge port 102. Electric energy is applied to the heater 111 in the built-in drive element 103 provided on the silicon substrate 101 through the electric circuit board 107 and the flexible circuit board 105 in accordance with a signal input from the outside via the electric connector 108. Performed by a transistor circuit. The built-in drive element 103 was formed on the silicon substrate 101 directly using a semiconductor process.

  A sealing material 112 is formed on the built-in drive element 103 so as not to be directly exposed to ink.

  A circuit block diagram for driving the ink jet recording head is shown in FIG.

  As described above, the ink jet recording head embodying the present invention has a substantially symmetric structure with respect to the ink supply port 110, and its drive circuit has a symmetric structure as well. For explanation, in FIG. 1, heater numbers (nozzle numbers) are given to the respective heaters 111 in order from the end. Since the heaters 111 of each nozzle row are shifted from each other by a half pitch, in FIG. 1, the upper half is a drive circuit belonging to the heater 111 having an odd nozzle number, and the lower half is a heater 111 having an even nozzle number. These drive circuits are configured such that they can be driven independently of each other.

  In the present invention, for the purpose of suppressing the instantaneous power consumption of the ink jet recording head and for the purpose of preventing pressure interference in the ink liquid chamber, the print data for one column is not printed at the same time, All heaters 111 are driven while being dispersed in time. At the time of driving, data for one column is transferred to the shift register 604, and then stored in the latch register 605. The decoder circuit 606 drives the data in a time division manner.

  In this embodiment, the nozzle on one side 2048 was divided into 8 blocks each having 256 blocks, and each block was driven in 256 time divisions. The decoder circuit 606 has eight input terminals, which are connected to the output signal of the counter circuit 612 driven by a clock signal input from the outside. With such a configuration, the number of signal lines for driving the decoder 606 can be reduced from eight to two (including reset signal lines) as compared with the conventional example shown in FIG.

  As described above, according to the present invention, the number of signal wirings for controlling the time-division driving timing is increased in the ink-jet recording head in which the input terminals of the decoder circuit 606 are increased, that is, the ink-jet recording head having a large number of time divisions. As a result, a cheaper inkjet recording head is provided.

  A second embodiment of the ink jet recording head of the present invention will be described with reference to FIGS.

  FIG. 5 is a drive circuit block diagram of the ink jet recording head according to the second embodiment of the present invention, and FIG. 6 shows a case where defective nozzles are complementarily driven using the ink jet recording head according to the second embodiment of the present invention. FIG. 7 is a schematic diagram schematically showing a printing dot when undischarge complementing driving is performed.

  The difference from the first embodiment of the present invention is that the input signal of the decoder circuit 606 can be input and selected from a signal system different from the output signal of the counter circuit 612, and for a defective nozzle, It is the point which was set as the structure which can perform complementary discharge with an adjacent nozzle.

  The discharge failure complement driving of the present embodiment will be described with reference to FIG. FIG. 6 shows an example in which there is a defect in the 507th nozzle, and complementary discharge is performed using the 508th nozzle. As for the driving of the other nozzles excluding the defective nozzle, the decoder circuit 606 is driven in accordance with the clock signal input to the counter circuit 612 in the same manner as in the first embodiment of the present invention, and the time division driving is performed. At this time, the SEL signal is set to the LOW level so that the output of the counter circuit 612 is input to the decoder circuit 606. While this non-complementary ejection is being performed, decoder input data corresponding to the 508th nozzle is input to the decoder input data storage shift register 607 and stored in the decoder input data storage latch register 608.

  Next, after the non-complementary discharge for one column is completed, the SEL signal is set to the HIGH level, and control is performed so that the output data of the decoder input data storage latch register 608 is input to the decoder circuit 606, and the 508th nozzle is controlled. Drive.

  By adopting such a configuration, the present embodiment can perform discharge failure complement driving with a smaller data transfer fee than the conventional example shown in FIG.

Drive circuit diagram of first embodiment of the present invention (counter circuit → Dec) Head external view of the first embodiment of the present invention Head sectional view of the first embodiment of the present invention Head sectional perspective view of the first embodiment of the present invention Drive circuit diagram of second embodiment of the present invention Non-discharge supplementary flying dot diagram of the second embodiment of the present invention Non-discharge complementary printing dot diagram of the second embodiment of the present invention Conventional head appearance Conventional head sectional perspective view Conventional head drive circuit diagram (all shift register type) Conventional head drive circuit diagram (block matrix type) Conventional adjacent discharge failure complement dot recording diagram Conventional adjacent discharge failure complement dot recording diagram

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Silicon substrate 102 Ink discharge port 103 Built-in drive element 104 Base plate 105 Flexible circuit board 106 Support member 107 Electric circuit board 108 Electric connector 109 Cap receptacle 110 Ink supply port 111 Heater 112 Sealant 114 Nozzle 117 Ink common liquid chamber 401 Dot 402 non-discharge dot 403 complementary discharge dot 501 print column 502 print dot 503 undischarge nozzle complementary dot 601 driver transistor 603 AND circuit 604 print data storage shift register 605 print data storage latch register 606 decoder circuit 607 decoder input data storage shift register 608 Decoder input data storage latch register 612 Counter circuit 613 3-state buffer

Claims (4)

An inkjet recording head having a plurality of nozzles for forming an image on a recording medium,
Having time-division driving means for driving each of the nozzles in a time-division manner;
2. The ink jet recording head according to claim 1, wherein the time-division driving means includes nozzle sequential selection means for sequentially selecting nozzles to be driven in a desired order in accordance with a clock signal input from the outside.   The nozzle sequential selection means includes a counter circuit that outputs a binary signal in accordance with an externally input clock signal, and a decoder circuit that selects a drive nozzle in accordance with an output signal of the counter circuit. The ink jet recording head according to claim 1. The time-division driving means is
The nozzle sequential selection means;
An individual nozzle selecting means capable of individually and electrically selecting an arbitrary nozzle in accordance with a nozzle selection signal input from the outside;
3. The ink jet recording head according to claim 1, further comprising a nozzle selection signal selection unit that selects which of the signals of the nozzle sequential selection unit and the nozzle individual selection unit is to be activated. An inkjet recording head recording method that forms an image by ejecting ink in accordance with an image signal input from the outside while scanning the recording medium once relative to the recording medium,
The inkjet recording head includes a plurality of nozzles at a pitch corresponding to an image recording density in the nozzle row direction in a nozzle row direction perpendicular to a scanning direction for scanning the inkjet recording head with respect to the recording material. Is formed,
An inkjet recording method for performing recording by driving the plurality of nozzles divided into a plurality of timings dispersed in time within an image recording density unit in the scanning direction,
The inkjet recording head has a nozzle group unit that is divided and driven at different timings within the image recording density unit among the plurality of nozzles, and the nozzles in the nozzle group unit , An ink jet recording method for electrical selection by the nozzle sequential selection step,
When the nozzle group unit has a normal nozzle that can eject ink and a defective nozzle that cannot eject ink, the normal nozzle corresponding to the pixel adjacent to the defective nozzle in the nozzle row direction is the defect. An inkjet recording method that performs dot complementation of the defective nozzle by driving in response to an image signal corresponding to a nozzle,
An ink jet recording method comprising: performing dot complementation of the defective nozzle by selecting a normal nozzle corresponding to a pixel adjacent to the defective nozzle in the nozzle row direction in the individual nozzle selection step.

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