JP2006305918A - Ink-jet recorder and method for recording - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a recorder such as a line printer for printing at a high speed with a recording head of broad width makes ink drying insufficiently at a paper-delivery section or just after delivering a paper due to the remarkable unevenness of the absorbency and fixability of a paper depending on environmental conditions and then tends to generate a tinting on printed portion. <P>SOLUTION: The printed portion is irradiated with a ultrasonic wave from the position close to the paper just after printing by the recording head. From the receiving amount of the ultrasonic wave which has permeated the image portion, the ink absorption characteristic of the applied paper is measured. Based on the measured result, the paper feeding speed is determined. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus and an ink jet recording method. More specifically, in a printing apparatus that has a fixed full multi-recording head having a recording element array corresponding to the printing width and performs high-speed inkjet printing, the inkjet recording apparatus controls the recording apparatus according to the ink absorption characteristics of the printing medium. And a recording method.

  Inkjet printing method using fixed type full multi-recording head with printing element array corresponding to printing width can print variable data, make plate, change ink color, etc. compared with conventional analog printing method Has been widely used for form printing, physical distribution printing, address printing, and the like. In general, such printing devices are installed continuously in offset, flexographic printing machines, etc., and their use has expanded from printing only variable data sections to printing all images such as ruled lines and layouts of forms. ing.

  These printing apparatuses are required not only to perform high-speed printing, but also to print delicate images such as characters, barcodes, graphics, and photographs at high speed on general printing media that do not have an inkjet ink receiving layer.

In such a printing apparatus, a water-soluble dye, a pigment dispersed with a water-soluble resin, a microencapsulated pigment, or a pigment having a hydrophilic group adsorbed on the surface is used as a coloring material, and the solvent is water as a main component. It is common to use inks containing water-soluble high-boiling solvents such as glycol and additives such as surfactants for the purpose of preventing drying and clogging, and using such inks for general printing When recording on a medium, a printing medium with poor absorbability has a problem that the printed matter is wound up or stacked before the ink penetrates the printing medium, and the printed matter is stained with ink. In order to prevent such inconveniences, a contrivance has been made such as installing a dryer on the downstream side of the printing unit and drying it sufficiently.
An ink jet printer is disclosed in which a dryer is arranged in a continuous printing system for drying printed matter.
(For example, Patent Document 1)
Proposals have also been made using microwaves as drying means.
(For example, Patent Document 2)
In addition, a technique is disclosed in which a dryer is provided on the downstream side of the printing machine so that the conveyance time and the fixing time can be changed in accordance with the printed area and the mass of ink used for printing.
(For example, Patent Document 3)

JP 08-216467 A JP 07-195683 A JP 05-270100 A

  However, in addition to the variety of types of general printing paper, ink jet suitability is not considered, so even with the same type of recording medium, there is a large variation in ink absorbability between production lots, and the same printing Even if the ink is dried under the conditions, the printed matter may be contaminated (such as set-off) due to insufficient fixability of the ink. This is considered to be caused by the filler on the surface of the print medium, the uneven distribution of the sizing agent, and the like.

  As described above, when high-speed continuous printing is performed on conventional printing paper using the inkjet method, in order to prevent contamination of the printed matter, the fixing time of the ink to be used on the printing paper is measured in advance and appropriate printing conditions are set. It is necessary to make the transport time and the fixing time variable according to the printed area and the mass of the ink used for printing, as disclosed in JP-A-05-270100. However, since the ink fixing time varies greatly depending on the type of print medium, production lot, and the environment in which the apparatus is installed, such a method cannot cope with such variable factors. . As a result, troubles such as a set-off of printed matter occur.

  Accordingly, an object of the present invention is to perform high-speed continuous ink jet printing using a fixed full multihead having a recording element array corresponding to the printing width, due to the type of print medium, variations in the production lot of the print medium, and changes in the operating environment of the apparatus. An object of the present invention is to realize an ink jet recording apparatus and an ink jet recording system that provide a good printed matter that does not show up after winding and stacking even if the absorbability of the ink into the print medium changes.

  The above object is achieved by the present invention described below. That is, the present invention provides an inkjet recording apparatus including a recording unit having at least one type of recording head, an ultrasonic transmission unit, an ultrasonic reception unit, and a recording medium conveyance unit, and uses ultrasonic intensity information detected from the ultrasonic reception unit. An ink jet recording apparatus comprising a control means for controlling a transport speed of a transport means, wherein the ultrasonic wave transmitting means and the ultrasonic wave receiving means are located downstream of the recording head in the transport direction of the recording medium. An ink jet recording apparatus arranged in pairs on the front and back of a recording medium. In addition, the present invention includes two or more pairs of the ultrasonic wave generation unit and the ultrasonic wave reception unit, which are arranged at different positions with respect to the recording medium conveyance direction. In the inkjet recording apparatus, the conveyance speed is controlled based on the detected change rates of a plurality of ultrasonic intensities.

  Also, the present invention provides an inkjet recording apparatus including a recording unit having at least one type of recording head, an ultrasonic wave generation unit, an ultrasonic wave reception unit, a recording medium transport unit, and a drying unit. An ink jet recording apparatus comprising: a control unit that controls a drying unit according to sound wave intensity information, wherein the ultrasonic wave generating unit and the ultrasonic wave receiving unit are downstream of the recording head in a conveyance direction of the recording medium. And an ink jet recording apparatus disposed in contact with the front and back of the recording medium. In addition, the present invention includes two or more pairs of the ultrasonic wave generation unit and the ultrasonic wave reception unit, which are arranged at different positions with respect to the recording medium conveyance direction. In the inkjet recording apparatus, the drying unit is controlled based on the detected change rates of a plurality of ultrasonic intensities.

Furthermore, the present invention is an ink jet recording method comprising at least the following steps.
A step of printing on a recording medium by a recording means having at least one type of inkjet recording head,
A step of applying ultrasonic waves to the printing surface by a plurality of ultrasonic wave generating means, and detecting the intensity at each receiving unit provided in a pair;
Calculating the detection signal to obtain ultrasonic intensity information;
The step of controlling the conveying speed based on the ultrasonic intensity information Further, the present invention is an ink jet recording method comprising at least the following steps.
(1) Step of printing on a recording medium by recording means having at least one type of ink jet recording head (2) Applying ultrasonic waves to the printing surface by a plurality of ultrasonic wave generating means, and receiving units provided in pairs Step of detecting intensity (3) Step of calculating the detection signal to acquire ultrasonic intensity information (4) Step of controlling drying means by ultrasonic intensity information

  The inkjet recording apparatus and the recording method of the present invention measure the ink absorption characteristics, which vary according to the type of printing medium, the production lot, and the environment in which the apparatus is operating, in real time using ultrasonic waves, and transport the recording apparatus. By controlling the speed or the dryer, it is possible to provide a printed matter having a good image free from contamination such as set-up caused by winding or stacking. Further, since the dryer is controlled based on the absorption characteristics, the dryer can be turned off at any time when it is not necessary, so that energy saving can be achieved.

  The best mode of the present invention will be described below.

In general, when ink lands on the printing surface of a print medium and an image is formed,
1. The air between the print medium fibers is replaced with ink by capillary action in the recording medium. 2. The ink is absorbed by the paper fibers.
3. As the ink is absorbed, the paper fibers swell and the air in the fiber structure replaces the ink.
Through this process, the ink is fixed on the print medium. The absorption characteristics of the ink into the print medium can be measured using ultrasonic waves. In other words, the process of replacing the air in the print medium with ink can be measured over time using the property that the ultrasonic transmission is higher as the density is higher (harder).

  Since the amount of ultrasonic transmission of ink is larger than that of air, the amount of ultrasonic transmission increases when the air between the paper fibers is replaced by the ink. As a result, the fibers in the printing area become soft and the amount of ultrasonic transmission decreases.

  The present invention utilizes the above phenomenon, provides a plurality of ultrasonic transmitters and receivers in the recording device, measures the change rate of ultrasonic intensity with time in real time, and obtains absorption characteristic information for the print medium, It sets the optimal conveyance speed or drying conditions for the print medium.

  A first embodiment of the present invention will be described with reference to FIG.

  The recording head 101 included in the ink jet recording apparatus of the present invention is a fixed line head having a large number of ink discharge ports.

  The recording head 101 may be a thermal ink jet system that ejects ink by thermal energy, or a piezo system that utilizes physical deformation of a pressure chamber.

  It is also possible to arrange a plurality of such recording heads in the transport direction to form a color printing apparatus. In order to obtain a high recording speed, it is also preferable to share and discharge ink of the same color from a plurality of recording heads.

  The recording head 101 of this embodiment discharges black ink. The resolution of the head varies depending on the type of printed matter. For example, when printing a two-dimensional barcode or a pattern, a resolution of 300 dpi (dot / inch) or more is preferable.

  In order to realize high-speed printing, it is essential that the recording width of the recording head is equal to or larger than the printing width of a desired printed matter.

  In order to perform color printing, a plurality of independent recording head groups are used for each color, and each head group requires four recording heads, black, cyan, magenta, and yellow. In the case of multi-color printing, at least as many recording heads as the types of recording liquids to be used are required. It is also possible to use light color inks of each color separately.

  The information processing apparatus 100 includes an application program for creating image data and a printer driver for controlling the recording apparatus. In the case of color printing, the RGB image data created by the application program is output by the printer driver, for example, C , M, Y, and K, and after that, recording data corresponding to the presence or absence (binarized signal) of ink ejected from each recording head is created.

  The abbreviations indicate R: red, G: green, B: blue, C: cyan, M: magenta, Y: yellow, and K: black.

  The print medium 102 is conveyed on a conveyance stage 107 by a take-up roller 103 provided downstream. The controller 106 and the take-up roller 103 are coupled by a cable (not shown), and are arranged so as to synchronize transmission / reception of a recording medium cueing signal and conveyance of the recording medium and printing. A driving motor (not shown) is coupled to the winding roller 103.

  Two sets of ultrasonic wave transmitting means 104-1 and 104-2 and ultrasonic wave receiving means 105-1 and 105-2 are arranged on the downstream side of the recording head 101 in the conveying direction, respectively, at positions sandwiching the print medium. Yes. The ultrasonic receiving means 104-1 and 104-2 detect the ultrasonic reception intensity at the time when the image formed by the ink ejected by the recording head 101 passes between the respective ultrasonic transmission / reception means. The oscillation frequency of the ultrasonic signal is preferably 1 to 10 MHz, particularly 1 to 2 MHz, in order to detect a change in ultrasonic intensity due to ink absorption.

The two or more detected ultrasonic intensities are sent to the information device 100, and the rate of change of the ultrasonic intensity is calculated. Since the detected ultrasonic intensity is relative, it is preferable to look at the rate of change of the value measured with two or more ultrasonic pairs.
The calculated change rate is referred to a table of intensity information and conveyance speed information stored in advance in the information processing apparatus as ultrasonic intensity information, and conveyance speed information corresponding to the intensity information is obtained, and the controller is used as a conveyance speed instruction value. 106.

FIG. 3 shows the positional relationship between the ultrasonic receivers 104-1 and 104-2, the recording head 101, and the print medium 102 as viewed from above.
FIG. 2 shows a second embodiment of the present invention. The same recording heads 201 to 204 as the recording head 101 described in the first embodiment are arranged on the conveyance path of the print medium. Two ultrasonic transmission means 205-1 and 205-2 and ultrasonic reception means 206-1 and 206-2 are arranged on the downstream side of the recording head in the conveying direction, and a dryer 207 is arranged further downstream. Has been. As the dryer 207, a halogen lamp, an infrared lamp, or a microwave oscillator can be used. Similar to the first embodiment, the intensity change rate is calculated from the ultrasonic intensity information, and the calculated change rate is stored in a table of intensity information and dryer control information stored in advance in the information processing apparatus as ultrasonic intensity information. Inquired and obtains dryer control information according to strength information. The dryer control information is sent to the controller 106, transmitted to the dryer 207 connected by a cable (not shown), and subjected to predetermined control. Specifically, the presence or absence of the operation of the dryer, the control of the lamp intensity, and the like.

FIG. 4 shows a printing flowchart of the ink jet recording apparatus of the present invention.
The information processing apparatus 100 creates ultrasonic intensity measurement pattern data, and when the user issues a print start command on the display screen, transmits the pattern data to the recording apparatus (S102).

  The information processing apparatus 100 transmits a conveyance start command for activating the print medium winding roller 103 and a transmission start command to the ultrasonic transmission unit almost simultaneously (S103).

  When the leading edge of the print medium 102 is detected by a sensor (not shown) after the start of conveyance (S112) (S113), a leading edge detection signal is transmitted to the recording apparatus (S114).

  In the recording apparatus, a printing operation is executed by the recording head 101 (S109), and an ultrasonic intensity measurement pattern is printed. In the information processing apparatus 100, intensity information is sent to the ultrasonic receiving means 105-1 and 105-2 at a predetermined timing when the ultrasonic intensity measuring pattern passes below the ultrasonic transmitting means 104-1 and 104-2. An ultrasonic intensity acquisition command is transmitted so as to be acquired (S104, 105).

  The ultrasonic receiving means 105-1 and 105-2 each transmit the acquired ultrasonic intensity to the information processing apparatus 100 (S118, 120). In the information processing apparatus 100, the rate of change of the two detected ultrasonic intensities is calculated, the table of intensity change rate information and the conveyance speed information stored in advance is referred, and the conveyance speed corresponding to the intensity change rate information is set. Then, the conveyance speed instruction value is transmitted to the drive control unit of the winding roller (S106).

  At the same time, the information processing apparatus 100 creates print data (S107). When the desired conveyance speed is reached, the take-up roller drive unit sends a print start command to the recording apparatus, and printing is executed (S110).

  After the completion of the predetermined printing operation, the information processing apparatus 100 receives an end status (S111) from the recording apparatus, transmits a conveyance motor stop signal (S121), stops the winding roller (S122), and ends the operation.

FIG. 5 shows another printing flowchart of the ink jet recording apparatus of the present invention.
The information processing apparatus 100 creates ultrasonic intensity measurement pattern data, and when the user issues a print start command on the display screen, transmits the pattern data to the recording apparatus (S202).

  The information processing apparatus 100 transmits a conveyance start command for activating the print medium winding roller 103 and a transmission start command to the ultrasonic transmission unit almost simultaneously (S203).

  After the start of conveyance (S213), when the leading edge of the print medium 102 is detected by a sensor (not shown) (S214), a leading edge detection signal is transmitted to the recording apparatus to start printing (S215).

  In the recording apparatus, a printing operation is executed by the recording head 101 (S209), and an ultrasonic intensity measurement pattern is printed. In the information processing apparatus 100, intensity information is sent to the ultrasonic receiving means 105-1 and 105-2 at a predetermined timing when the ultrasonic intensity measuring pattern passes below the ultrasonic transmitting means 104-1 and 104-2. An ultrasonic intensity acquisition command is transmitted so as to be acquired (S204, 205).

  The ultrasonic receiving means 105-1 and 105-2 transmit the acquired ultrasonic intensity to the information processing apparatus 100 (S219, 221). The rate of change is calculated based on the two detected ultrasonic intensities, the table of intensity information and drying condition information stored in advance is queried, drying conditions are set according to the intensity information, and sent to the dryer 207. (S206).

  Subsequently, the information processing apparatus 100 creates print data (S207). When the desired conveyance speed is reached, the take-up roller drive unit sends a print start command to the recording apparatus, and printing is executed (S210).

After the completion of the predetermined printing operation, the information processing apparatus 100 receives an end status (S211) from the recording apparatus, transmits a conveyance motor stop signal (S222), stops the winding roller (S216), and ends the operation.
In the above, the conveyance speed control and the drying means control are performed separately, but they may be performed in combination.

  The present invention is mainly applicable to a high-speed line printer, in particular, an ink jet recording apparatus.

1 is a schematic diagram of an ink jet recording apparatus embodying the present invention. It is a schematic diagram of another inkjet recording apparatus which implemented this invention. 1 is a top view of an ink jet recording apparatus embodying the present invention. 3 is a flowchart of an ink jet recording method embodying the present invention. It is another flowchart of the inkjet recording method which implemented this invention.

Explanation of symbols

100 Information processing device (host PC)
101 Recording head
102 print media
103 Winding roller (Rewinder)
104-1,104-2 Ultrasonic transmission means
105-1,105-2 Ultrasonic wave receiving means
106 controller
107 Transfer stage

201,202,203,204 Recording head
205-1,205-2 Ultrasonic transmission means
206-1,206-2 Ultrasonic wave receiving means
207 Drying means

Claims (12)

  In an inkjet recording apparatus including a recording unit having at least one type of recording head, an ultrasonic transmission unit, an ultrasonic reception unit, and a recording medium conveyance unit, the conveyance speed of the conveyance unit is controlled based on information obtained from the ultrasonic reception unit. An ink jet recording apparatus comprising a control means.   2. The inkjet recording according to claim 1, wherein the ultrasonic wave transmitting unit and the ultrasonic wave receiving unit are arranged in pairs on the front and back of the recording medium on the downstream side in the conveyance direction of the recording medium with respect to the recording head. apparatus.   3. The ink jet recording apparatus according to claim 2, wherein two or more pairs of the ultrasonic wave transmitting unit and the ultrasonic wave receiving unit are included, and are arranged at different positions with respect to the conveyance direction of the recording medium.   The inkjet recording apparatus according to claim 3, wherein the ultrasonic intensity information is a change rate of a plurality of ultrasonic intensities detected by the plurality of arranged ultrasonic receiving units.   The inkjet recording apparatus according to claim 4, wherein the inkjet recording head is a fixed full multihead having a recording element array corresponding to a printing width.   In an ink jet recording apparatus including a recording unit having at least one type of recording head, an ultrasonic transmission unit, an ultrasonic reception unit, a recording medium transport unit, and a drying unit, a drying unit based on ultrasonic intensity information detected from the ultrasonic reception unit An ink jet recording apparatus comprising control means for controlling the ink jet recording apparatus.   The inkjet recording according to claim 6, wherein the ultrasonic transmission unit and the ultrasonic reception unit are arranged in pairs on the front and back of the recording medium on the downstream side of the recording head in the conveyance direction of the recording medium. apparatus.   8. The ink jet recording apparatus according to claim 7, comprising two or more pairs of the ultrasonic wave transmitting means and the ultrasonic wave receiving means, which are arranged at different positions with respect to the conveyance direction of the recording medium.   9. The ink jet recording apparatus according to claim 8, wherein the ultrasonic intensity information is a change rate of a plurality of ultrasonic intensities detected by the plurality of arranged ultrasonic receiving means.   The inkjet recording apparatus according to claim 9, wherein the inkjet recording head is a fixed full multi-multi head having a recording element array corresponding to a printing width. Printing on a recording medium by a recording means having at least one type of inkjet recording head;
A step of applying ultrasonic waves to the printing surface by a plurality of ultrasonic transmission means, and detecting the intensity at receiving portions provided in pairs on the front and back of the printed matter,
Calculating the detection signal to obtain ultrasonic intensity information;
An inkjet recording method comprising a step of controlling a conveyance speed of a print medium based on ultrasonic intensity information. Printing on a recording medium by a recording means having at least one type of inkjet recording head;
A step of applying ultrasonic waves to the printing surface by a plurality of ultrasonic transmission means and detecting the ultrasonic intensity by receiving means provided in pairs;
Calculating the detection result to obtain ultrasonic intensity information;
Controlling the drying means according to the ultrasonic intensity information;
An ink jet recording method comprising:

Images