JPH0976556A - Spot color laser beam printer and spot color printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam printer adaptive to spot color print in one or two colors on a sheet previously monochromatically printed. SOLUTION: The laser beam printer comprises a printer body and an electrophotographic recorder. The body has a guide roller for guiding a continuous recording sheet 5 to the recorder. The recorder has a charger, a laser optical system 8, a developing unit 7B, a transfer unit 7C disposed around a photosensitive drum and a fixing unit 9 disposed at the rear. The fixing unit 9 has a heat roller 92 for heating. Further, an ink jet recorder 3 disposed at the rear side of the fixing unit 9 is provided. An ink jet recorder recording head is disposed at the place where the sheet becomes a temperature of 100 deg.C or lower.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser beam printer, and more particularly to a laser beam printer capable of high speed spot color printing and a printing method using the same.

[0002]

2. Description of the Related Art A high-speed laser beam printer has an ability to perform high-speed printing of about 5,000 lines / minute to 16,000 lines / minute in monochrome on continuous recording paper.

By the way, recently, a spot color printing method has been recently demanded in which color printing of one or two colors is performed on a paper which has been previously monochrome printed. This is used in order to make the material more conspicuous by printing the logo mark of the organization or the like in color on a large amount of distributed material or the like. However, in order to do this with a laser beam printer, another printer is required, resulting in very expensive printing. Therefore, it was naturally considered to apply an inkjet printing method, which is an inexpensive printing method, but in the water-based ink method, the drying time of the ink is 5 to 10
It took a long time, and it was impossible to print at the same speed.
For this reason, use with an inkjet printer that uses a solid ink that solidifies instantly is under consideration. However, it is difficult to increase the number of nozzles in the print head for solid ink, and it is difficult to perform wide color printing.

[0004]

On the other hand, the present inventor succeeded in increasing the number of nozzles and lengthening the print head of an ink jet printer using an aqueous ink (see, for example, Japanese Patent Application No. 07-135185). The remaining issue is the development of a rapid drying method for water-based inks.

An object of the present invention is to provide a laser beam printer suitable for spot color printing with a color of 1 to 2 colors using a water-based ink on a paper which has been previously monochrome printed at high speed, and a printing using the same. To provide a method.

[0006]

The above-mentioned object is provided with a printer body and an electrophotographic recording section, and the printer body is
A guide roller for guiding the continuous recording paper to the electrophotographic recording unit is provided, and the electrophotographic recording unit is provided with a charger, a laser optical system, a phenomenon machine, a transfer unit around the photosensitive drum, and a fixing unit located behind the charger. In the laser beam printer having a heating roller for heating, the fixing device includes an ink tank, a recording head, and a recording paper conveying unit, and includes an inkjet recording unit disposed on the rear side of the fixing device. This is achieved by arranging the recording head at a location where the continuous recording paper heated by the heat roller has a temperature of 100 ° C. or lower.

[0007]

[Function] The moisture absorbed in the recording paper is
Immediately after leaving the fixing device heated to 0 to 140 ° C., the continuous recording paper is completely dried and the temperature thereof is rapidly lowered by the heat of evaporation. When printing with a water-based ink on the recording paper in this state, it is dried almost instantly, and high-quality printing without bleeding peculiar to the water-based ink becomes possible. 160 as long as a fixed inkjet printhead is used
A printing speed of 00 lines / minute to 20000 lines / minute can also be supported. However, when printing on recording paper of 100 ° C or higher, the line width becomes wider due to ink scattering, so the head temperature of the recording paper is 1
Set it to a position where it will be below 00 ° C.

The temperature of the recording paper is below 100 ° C.
It is about 30 cm or more away from the fixing device, and the ink jet recording section should be set at this position.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a transverse sectional view showing an embodiment of a laser beam printer capable of high-speed spot color printing according to an embodiment of the present invention. In the figure, 1 is a printer main body of a laser beam printer, 2 is an electrophotographic recording unit for performing monochrome printing, 3 is an inkjet recording unit for performing spot color printing, 4 is a controller,
6A is a paper feed tray for storing the continuous recording paper 5 to be supplied to the printer main body, and 6B is a discharge tray for storing the image-formed continuous recording paper 5.

The electrophotographic recording section 2 comprises a charging device 7A, a laser optical system 8, a developing device 7B, a transfer device 7C and a fixing device 9. A cantilever 10 is arranged between the developing device 7B and the fixing device 9.

The charging device 7A includes a cleaning device and a charging device 7A that charges the surface of the photosensitive drum 71 after being cleaned by the cleaning device. The laser optical system 8 supplies a laser beam 82 for forming a latent image on the surface of the photosensitive drum 71 through a laser light inlet 81.

The developing device 7B is a developing roller 7 for developing toner on the surface of the photosensitive drum 71 on which the latent image is formed.
3 is provided.

The fixing device 9 is provided with a belt-shaped preheater 91 provided along the conveyance direction of the continuous recording paper 5, a heating heat roller 92, a pressure roller 93, a ventilation path 94, and an exhaust fan 95.

The ink jet recording section 3 is composed of an ink jet recording head 31 for ejecting ink, a platen roller 32, a drying zone 33, a tension roller 34 and a drive roller 35. The inkjet recording unit 3 further includes an ink cartridge, a carriage that conveys the recording head, and a guide rail.

The recording head 31 is fixed by the fixing device 9 to 13
The continuous recording paper 5 heated to 0 to 140 ° C. is arranged at a place where the temperature becomes 100 ° C. or less. As a specific example, it is about 30 cm or more away from the heat roller 92 of the fixing device 9. The length of the drying zone 33 between the platen roller 32 and the tension roller 34 must be at least 40 cm or more, which is the distance required for the continuous recording paper 5 to dry.

The controller 4 includes a CPU 41 for controlling the electrophotographic recording unit 2 and the inkjet recording unit 3, and this CPU operates according to a program stored in the ROM 42. 43 stores coded print data or image data and develops the print data into image data printable by the electrophotographic recording unit 3 and the inkjet recording unit 10,
It is a memory for storing.

The height of the laser beam printer of this embodiment is approximately 1.4 m and the width thereof is 2.3 m.
It has the ability to perform high-speed color printing at about 0 lines / minute.

2 to 3 show details of an example of the configuration of the head 31 of the ink jet recording section 3. 2 is a sectional view of one nozzle row of the ink jet recording head, and FIG. 3 is an enlarged view of the vicinity of the silicon substrate 1 shown in this sectional view. The head 31 includes a plurality of heating resistors 30 including a thin film resistor and a thin film conductor on the first surface of the Si substrate 301.
3, a driving LSI 302 for driving the heating resistor, a driving wiring 307, etc. are formed. The orifice plate 31 is provided with a plurality of ejection openings 312 for ejecting ink droplets in a direction perpendicular or substantially perpendicular to the heating resistors 303 by sequentially energizing the heating resistors 303 in pulses.
1 is provided. A plurality of individual ink passages 309 are provided corresponding to each of the plurality of ejection ports 312, and a common ink passage 310 is provided so as to communicate all of these individual ink passages.

The individual ink passages 309 and the common ink passages 310 are formed on the first surface of the Si substrate 1 by the partition layer 3.
08, and the orifice plate 3 is formed on the partition layer.
11 are provided. The common ink passage 310 is connected to the ink supply port 318 of the frame 317 through the ink groove 314, the connection hole 315, and the ink groove 316, and the ink supply port 318 is further connected to the ink supply pipe 319. 321 is a connector.

The head 31 of the ink jet recording section 3 is
One or a plurality of them are mounted on a carriage that can move on a guide rail extending in a direction orthogonal to the transport direction of the continuous recording paper 5. This is for moving the head 31 to the printing position in order to form a spot color image at an arbitrary position on the continuous recording paper 5.

According to the present invention, first, the electrophotographic recording unit 2
At the same time, normal monochrome printing was made on the continuous recording paper 5,
Then, the inkjet recording unit 3 performs spot-color printing on the continuous recording paper 5.

That is, at the time of printing, in the electrophotographic recording section 2,
A latent image of a recorded image is formed by laser light on the surface of the photosensitive drum 71 charged by the charger 7A. Next, the developing roller 73 develops the latent image with toner. On the other hand, the continuous recording paper 5 in the paper feed tray is the electrophotographic recording unit 2
Of the toner image formed on the surface of the photosensitive drum 71 while being guided between the photosensitive drum 71 and the transfer unit 7C after passing through the guide roller in the printer body 1. After receiving the transfer, it is conveyed to the fixing device 9. In the fixing device 9, the toner on the continuous recording paper 5 is heated and pressed by the heat roller 92 and the pressure roller 93, and the toner image is fixed on the continuous recording paper 5.

The cantilever 10 is for absorbing the speed difference between the photosensitive drum 71 and the heat roller 92.
When the speed of the heat roller 92 is too high, the amount of the heat roller 92 is detected and the speed of the heat roller 92 is suppressed. Further, the speed of the drive roller 35 is controlled so that the position of the tension roller 34 is detected and the tension acting on the continuous recording paper 5 is made constant. These controls are executed by the controller 4.

After the continuous recording paper 5 passes through the fixing device 9,
Further, it is guided to the inkjet recording unit 3. The continuous recording paper 5 is conveyed to the inkjet recording head 31 by a platen roller 32 and a pinch roller and spot-color printed with liquid ink.

The position of the head 31 of the ink jet recording section 3 is set at a position where the heated continuous recording paper 5 becomes 100 ° C. or lower. Then, the continuous recording paper 5 is conveyed through the drying zone by the tension roller 34 and the drive roller 35, and is further discharged from the paper discharge port to the paper discharge tray 6B.

By the fixing device 9, the continuous recording paper 5 is
Heat to 140 ° C. The continuous recording paper 5 heated by the fixing device 9 abruptly evaporates the water stored after leaving the fixing device, and is rapidly cooled by the heat of evaporation at this time, and at a distance of about 30 cm from the fixing device 9. It will be below 100 ° C. The ventilation passage 94 is for discharging the vapor at this time to the outside and efficiently drying and cooling the continuous recording paper 5, and the fan 95 forcibly exhausts the vapor to dry and cool the continuous recording paper 5.

When spot color printing is performed with liquid ink on the continuous recording paper 5 heated and dried by the fixing device 9,
It is dried for 0.5 sec or less so as not to be retransferred to others. That is, since the running speed of the continuous recording paper 5 in the laser beam printer having the capability of 16000 lines / second is about 83 cm / sec, the continuous recording paper 5 is sufficiently dry after running about 40 cm from the head 31, There is no problem even if the tension roller etc. touches the surface. The drying zone and the tension roller must satisfy at least the conditions for drying the spot-printed liquid ink.

The two drive rollers respectively detect the positions of the cantilever and the tension roller, and the rotational speeds thereof are adjusted.

There are nozzles that do not eject ink depending on the spot color printing, and there is a possibility that the ink of these nozzles gradually thickens and clogging occurs. Therefore, for the purpose of preventing clogging, it is desirable to perform a dummy discharge for preventing clogging from all nozzles at a rate of once or more every 10 minutes.

It is most effective that the dummy discharge from all the nozzles for preventing clogging is performed at the crease position of the continuous recording paper 5 with the perforations.

Although the electrophotographic recording method is adopted in the above embodiment in order to perform monochrome printing on the continuous recording paper 5 in advance, another printing method may be used as long as the printing involves heating the recording paper.

[0032]

According to the present invention, the water occluded in the continuous recording paper during monochrome printing evaporates immediately after it leaves the fixing device of the electrophotographic recording section, and the recording paper is completely dried.
When spot color printing is performed with a water-based ink on a continuous recording paper that has reached a temperature of 100 ° C. or less, the ink dries almost instantly, and high-quality printing without bleeding peculiar to the water-based ink becomes possible. Therefore, 16000 lines / minute to 2
Spot color printing capable of printing at a printing speed of 0000 lines / minute is possible with a small and inexpensive device.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a laser beam printer capable of high-speed spot color printing according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of one nozzle row of the ink jet recording head of the inkjet recording unit in FIG.

FIG. 3 is an enlarged view of the vicinity of the silicon substrate shown in the cross-sectional view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Printer body of laser beam printer, 2 ... Electrophotographic recording part, 3 ... Inkjet recording part, 4 ... Controller, 5 ... Continuous recording paper, 9 ... Fixing device, 91 ... Preheater, 92 ... Heating roller, 31 ... Inkjet recording head 31, 32 ... Platen roller, 33 ... Drying zone, 34 ... Tension roller

Claims (6)

[Claims] 1. A printer body and an electrophotographic recording section are provided,
The printer body is provided with a guide roller that guides continuous recording paper to the electrophotographic recording unit, and the electrophotographic recording unit includes a charger around the photosensitive drum, a laser optical system, a phenomenon machine, and a transfer unit. A laser beam printer having a heat roller for heating, which includes an ink tank, a recording head, and a recording paper conveying unit,
The inkjet recording unit is provided on the rear side of the fixing device, and the recording head is disposed at a position where the continuous recording paper heated by the heat roller has a temperature of 100 ° C. or less. Characteristic laser beam printer. 2. A printer body and an electrophotographic recording section are provided,
The printer body is provided with a guide roller that guides continuous recording paper to the electrophotographic recording unit, and the electrophotographic recording unit includes a charger around the photosensitive drum, a laser optical system, a phenomenon machine, and a transfer unit. A laser beam printer having a heat roller for heating, which includes an ink tank, a recording head, and a recording paper conveying unit,
An inkjet recording unit is provided on the rear side of the fixing device, wherein the position of the recording head is a position where the temperature of the recording paper heated by the heat roller is 100 ° C. or lower, the fixing device and the recording head. The vapor discharged from the continuous recording paper is discharged to the outside in the interval to efficiently dry the recording paper.
2. The laser beam printer according to claim 1, wherein a ventilation passage for cooling is provided and forced exhaust is performed by a fan. 3. The recording head comprises a plurality of heat generating resistors formed of a thin film resistor and a thin film conductor formed on a first surface of a Si substrate, and the same Si substrate for driving the heat generating resistors. Drive LSI formed and connected to the heating resistor
A plurality of ejection ports for ejecting ink droplets in a direction perpendicular or substantially perpendicular to the heating resistors by sequentially energizing the plurality of heating resistors in a pulsed manner, and corresponding to the plurality of ejection ports, respectively. And a plurality of individual ink passages provided on the Si substrate, a common ink passage provided on the Si substrate so that all of the individual ink passages communicate with each other, and the entire length of the common ink passage is electrically connected. The above Si
One ink groove provided on the substrate and at least one connection formed on the second surface of the Si substrate so that the ink groove communicates with the second surface which is the back surface of the first surface of the Si substrate. 3. A laser beam printer according to claim 1, wherein the laser beam printer is composed of a head chip of a Si substrate having a hole and a frame having a predetermined ink supply path and mounting the head chip. 4. The recording head is configured so as to perform clogging prevention dummy ejection from all nozzles at a rate of once or more in 10 minutes.
Laser beam printer described. 5. The laser beam printer according to claim 4, wherein the dummy ejection from all the nozzles is configured to be performed at a perforated position of perforations of the continuous recording paper. 6. A printer body and an electrophotographic recording section are provided,
The printer body is provided with a guide roller that guides continuous recording paper to the electrophotographic recording unit, and the electrophotographic recording unit includes a charger around the photosensitive drum, a laser optical system, a phenomenon machine, and a transfer unit. The fixing device is a spot color printing method in a laser beam printer having a heat roller for heating, which transfers a toner image to continuous recording paper in the electrophotographic recording unit. , Monochrome printing is performed by heating and fixing the continuous recording paper by the heat roller of the fixing device, and the continuous recording paper heated by the heat roller is placed at a temperature of 100 ° C. or lower. In the laser beam printer, the spot color printing is performed on the continuous recording paper by the inkjet recording unit. Pot color printing method.