JP2002234143A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an ink receiving layer on a recording sheet, as required, when printing is performed using a recording sheet in which an ink receiving layer is not formed. SOLUTION: A roller 1 wound with a recording sheet, a sensor 6 and an ink receiving layer forming section 5 are disposed in this order and when the sensor detects a plain recording sheet, an ink receiving layer is formed on the recording sheet P at the ink receiving layer forming section 5 before the recording sheet P is carried to a print section 2 for printing. Consequently, a high quality blur free image can be printed even on a plain recording sheet similarly to a print sheet in which an ink receiving layer is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer.

[0002]

2. Description of the Related Art An ink jet printer prints an image (including characters and the like) by discharging minute droplets of ink onto a recording paper. In this case, if the ink is directly ejected onto plain paper, the ink does not blend with the printing paper and the image bleeds, and there is a problem that it is generally difficult to obtain a high-definition (high-quality) image. For this reason, in order to obtain a high quality image with little bleeding, a recording paper in which an ink receiving layer made of a porous inorganic pigment such as silica or alumina is applied in advance to the paper surface is used. Conventionally, inexpensive recording paper having no ink receiving layer is set at the recording paper set position and printing is performed.If high quality printing is desired, the recording paper is replaced to form the ink receiving layer. The expensive recording paper was set at the set position and printing was performed.

[0003]

However, it is troublesome to change the type of recording paper between normal image quality and high quality printing each time, and the recording paper on which the ink receiving layer is formed. Since paper is more expensive than ordinary recording paper, there is a problem in that always providing both types of recording paper is costly.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and when printing is performed using a recording paper on which an ink receiving layer is not formed, an ink jet printer capable of forming an ink receiving layer as necessary. It is intended to provide a printer.

[0005]

According to a first aspect of the present invention, there is provided an ink jet printer for recording an image by discharging ink from a printing unit onto a recording sheet. A transport section that configures a transport path for transporting the recording paper from the set position to at least the print section, and is provided to face the transport path between the set position and the print section, and forms an ink receiving layer on the recording paper surface. And an ink receiving layer forming means.

According to this configuration, even when plain paper not coated with an ink receiving layer is used, printing is performed after the ink receiving layer is applied to the surface of the plain paper by the ink receiving layer forming means. Therefore, even when plain paper is used, a high-quality image free from bleeding can be obtained in the same manner as the recording paper on which the ink receiving layer is applied and formed.

According to a second aspect of the present invention, there is provided a sensor for detecting whether or not a recording sheet has an ink receiving layer formed in a conveyance path between the set position and the ink receiving layer forming means. The inkjet printer according to claim 1, wherein: According to this configuration, since the sensor detects whether or not the recording paper is coated with the ink receiving layer, the ink receiving layer forming unit can be driven as necessary.

According to a third aspect of the present invention, there is provided the ink jet printer according to the first or second aspect, further comprising switching means for switching whether to drive the ink receiving layer forming means. According to this configuration, since the switching means is provided, the ink receiving layer forming means can be driven or not driven by manual operation. In addition, it is possible to automatically switch between driving and non-driving according to the detection result of the sensor.

According to a fourth aspect of the present invention, the switching means includes:
4. The ink receiving layer forming means is driven in response to detecting that the sensor is a recording sheet having no ink receiving layer formed thereon.
It is an inkjet printer of the description. According to this configuration, since the sensor for detecting the ink receiving layer is provided and the switching unit is driven according to the reaction of the sensor, the driving of the ink receiving layer forming unit can be automatically performed.

According to a fifth aspect of the present invention, the ink receiving layer forming means includes a container accommodating the ink receiving layer material, a coating roller provided opposite the ink receiving layer material outlet of the container, and the coating roller. 5. The ink receiving layer forming roller pair including a roller and a pressure roller urged toward the application roller and opposed to each other with the transport path interposed therebetween, the roller comprising: 2. The inkjet printer according to item 1.

According to this configuration, since the ink receiving layer is formed on the photographic paper by the application roller, it is possible to form the ink receiving layer uniformly and uniformly on the photographic paper.

According to a sixth aspect of the present invention, the recording paper is a long body wound in a roll shape and is set at the set position so as to be able to be fed out. An inkjet printer according to any one of the above. According to this configuration, since the recording paper is formed of a roll-shaped long body, high-speed printing becomes possible when performing continuous printing.

The invention according to claim 7 is characterized in that a cutter section for cutting recording paper to a required size is provided downstream of the printing section. It is an inkjet printer. According to this configuration,
Since the cutter unit is provided, the recording paper can be cut at every frame or at a desired length.

[0014]

FIG. 1 shows an embodiment of an ink jet printer according to the present invention. This ink jet printer includes a roller 1 as recording paper setting means, a printing unit 2 provided at a predetermined position, and a cutter unit 3 for cutting the recording paper after printing into a required size. And a transport unit 4 that configures a transport path for transporting the recording paper to the cutter unit 3 via the printing unit 2. Further, an ink receiving layer forming section 5 for applying the ink receiving layer material to the recording paper surface and a sensor 6 on the upstream side thereof are disposed in the transport path between the roller 1 and the printing section 2.

The roller 1 is connected to a rotary drive mechanism such as a motor (not shown), and is configured to be rotated in the direction of the arrow when the drive power of the operator is turned on. The roller 1 can be inserted (set) so that the recording paper P wound in a roll shape can be rotated.

The printing unit 2 includes a printing head 21 and a printing table 22.
In addition, the print head 21 is connected to the print head 21 so that image information to be printed from the image processing unit 24 can be output. The print head 21 has a length corresponding to, for example, the width of the recording paper, and is disposed above the print table 22 with a predetermined gap therebetween and in parallel with the width direction. The print head 21 employs a known inkjet head, in which a plurality of minute holes are arranged and formed at a predetermined minute pitch in the width direction, and the presence or absence or the amount of ejection of ink is controlled in each minute hole. For example, a discharge control function unit using a piezoelectric element or the like is incorporated. An image processing unit 24 that outputs a print image is connected to the print head 21. The image processing unit 24 outputs image information for lines corresponding to the number of lines of the head from the image processing unit 24 to the transport speed of the recording paper P by the transport unit 4. Relatedly, line images are sequentially output and printed at a preset speed. The image processing unit 24 temporarily stores, for example, an image (including text data) transferred from an external information processing unit or an image read by a scanner as a print image, and outputs the image in line units.

Note that the print head 21 is not linear,
A planar head having a required width in the transport direction may be used. Further, in an aspect capable of color printing, inks of a plurality of colors such as three primary colors can be ejected in the transport direction.

The printing table 22 has a large number of small holes formed on the surface thereof, and a fan 231 of a suction portion 23 provided on the lower surface thereof.
Is rotated to generate a negative pressure, so that the recording paper P located on the printing table 22 is attracted to the surface of the printing table 21, eliminating the bending of the recording paper P and stabilizing the distance from the printing head 21. Is to be held.

The cutter portion 3 is a fixed blade 3 provided so as to face downwardly with a vertically long upper blade 31 which is movable in the width direction.
2, and the fixed blade 32 is provided in a collection chamber 33 for collecting chips and the like. The upper blade 31 receives a driving force from an elevation drive unit (not shown) and moves downward to mesh with the fixed blade 32, thereby enabling the recording paper P to be cut.

The transport section 4 includes a pair of rollers 41 on the downstream side of the printing section 2 and a pair of rollers on the downstream side of the cutter section 3, and guide pieces for suitably guiding the recording paper P on the upper surface upstream of the printing table 22. Part 43 and a guide piece part 44 for suitably guiding the recording paper P between the upper blade 31 and the fixed blade 32 of the cutter part 3.
And In the present embodiment, the recording paper P is of a type whose driving is started from a state where the leading end is nipped at least by the roller pair 41. Note that a configuration may be adopted in which an upstream roller pair is provided immediately upstream of the printing unit 2.

The ink receiving layer forming section 5 has a container 51 having a length corresponding to the width of the recording paper P in which the ink receiving layer material is built (stored), and the ink receiving layer material from the container 51 is adhered to the peripheral surface. Application roller 521 and the application roller 5
Crimping roller 5 urged to hold the conveyance path on the 21 side
22 is provided.

The container 51 has a lowering roller 511 arranged in parallel so as to cover a slit serving as an outlet of a member formed in parallel with the lengthwise direction. The peripheral surface of the application roller 521 is disposed in contact with the surface, so that the ink receiving layer material in the container 51 is evenly supplied to the peripheral surface of the application roller 521. The roller pair 52 may be driven and rotated by receiving the transfer force of the recording paper P being conveyed, but is similar to the roller pairs 41 and 42 in achieving more appropriate (desired thickness) of the ink receiving layer material. It may be configured to be driven by a driving unit such as a motor at a constant speed.

The container 51 is filled with an ink receiving layer material obtained by dispersing a porous inorganic pigment in water and adding an adhesive thereto. The porous inorganic pigment comprises synthetic silica or hydrated aluminum oxide. Synthetic silica refers to a synthetic silicon compound mainly composed of silicon dioxide. Further, hydrated aluminum refers to aluminum salts such as aluminum sulfate, aluminum nitrate, and aluminum chloride. The adhesive is
Cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose are used. Applying an ink receiving layer material made of a porous inorganic pigment to the surface of the recording paper P;
An ink receiving layer having a pore size of 50 to 5000 Å is formed.

The switching unit 53 drives the container 51 and the application roller 521 up and down, for example, integrally with respect to the transport path by driving means (not shown) such as a motor and a solenoid.
21 is moved toward and away from the pressure roller 522. Thus, it is possible to switch between the application and non-application of the ink receiving layer material on the surface of the recording paper P according to the type of the recording paper.

The sensor 6 detects the type of the recording paper P, that is, whether or not the recording paper P is coated with an ink receiving layer. The sensor 6 is, for example, a dielectric sensor or the like, and detects the presence or absence of an ink receiving layer material from a difference in dielectric constant depending on the material of the recording paper. Further, a distance sensor (for example, a PSD having a light emitting unit and a light receiving unit and using a triangulation method) that can detect the presence or absence of the ink receiving layer can also be applied as a proximity sensor. Further, a sensor that determines a difference in surface properties by a sensor that is in direct contact is applicable.

Next, the printing operation of the recording paper P will be described.

The recording paper P is sent out from the roller 1 onto the transport path, and the sensor 6 detects whether or not an ink receiving layer is formed on the recording paper P. If the ink receiving layer is formed on the recording paper P, the switching unit 53 operates to raise the application roller 521 so that the ink receiving layer forming unit 5 is not driven. If the ink receiving layer is not formed on the recording paper P, the switching unit 53 does not operate and the ink receiving layer forming unit 5 is driven. When the ink receiving layer forming section 5 is driven, the material of the ink receiving layer in the container 51 is transferred to the material discharging roller 5.
11, the ink is uniformly supplied to the peripheral surface of the application roller 521. The roller pair 52 receives the transfer force of the recording paper P being conveyed and rotates passively, so that the ink receiving layer material is uniformly applied and formed on the upper surface side of the recording paper P via the application roller 521. Recording paper
After the ink receiving layer is formed on P, the deflection of the recording paper P is removed by the negative pressure of the suction fan 231, and the print head 21 is moved based on image data transferred from an external information processing unit (not shown). When driven, an image is formed on the recording paper P.
The recording paper P on which the image is formed is conveyed to the cutter unit 3 by the roller pair 41. Recording paper P conveyed to cutter unit 3
Is cut into a predetermined length by the upper blade 31 and the fixed blade 32 of the cutter unit 3 and is carried out.

In the present embodiment, the ink receiving layer forming section 5 is of the coating type using a roller. However, the present invention is not limited to this, and the ink receiving layer forming section of the same ink jet type as the print head 21 is employed. May be. In this method, since the ink receiving layer formation is separated from the recording paper, when the switching unit 53 performs switching as in the roller method, the switching is performed without raising and lowering the ink receiving layer forming roller by a motor (not shown). It can be carried out. In addition, a structure in which a beak-shaped nozzle is formed at the lower part of the container 51 may be used.

In the ink jet printer according to the present invention, an external computer for transmitting image data is connected, and paper having no ink receiving layer, such as plain paper, is selected by setting on the screen of the computer. Sometimes, the ink receiving layer forming device may be driven.
Further, an ink jet printer that drives an ink receiving layer forming apparatus when a photograph mode (a large amount of data due to high gradation) is selected in an operation unit (not shown) of an external computer or an ink jet printer may be used.

[0030]

According to the first aspect of the present invention, even when plain paper having no ink receiving layer applied thereto is used, after the ink receiving layer is formed on the plain paper surface by the ink receiving layer coating means. Since printing is performed, high-definition with no bleeding is obtained as with printing paper on which an ink receiving layer has been formed in advance.
(High quality) images can be obtained.

According to the second aspect of the present invention, it is possible to determine whether or not the ink receiving layer is formed on the printing paper by providing the sensor, and to drive the ink receiving layer as necessary.

According to the third aspect of the present invention, the ink receiving layer forming means can be driven manually.

According to the fourth aspect of the present invention, the driving of the ink receiving layer forming apparatus can be automatically performed.

According to the fifth aspect of the present invention, the ink receiving layer can be uniformly applied to the printing paper.

According to the sixth aspect of the invention, high-speed printing can be performed.

According to the seventh aspect of the present invention, the printing paper is
It can be cut at every frame or at a predetermined length.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of an inkjet printer according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 roller 2 printing unit 3 cutter unit 4 transport unit 5 ink receiving layer forming unit 6 sensor 51 container 52 roller pair 521 application roller 522 pressure roller 53 switching unit

Claims (7)

[Claims] 1. An ink jet printer that records an image by ejecting ink from a printing unit onto a recording paper surface, a transport unit that configures a transport path that transports the recording paper from a set position where the recording paper is set to at least the printing unit. And an ink receiving layer forming means for forming an ink receiving layer on a recording paper surface, the ink receiving layer forming means being provided to face the conveyance path between the setting position and the printing section. 2. A sensor for detecting whether or not a recording sheet having an ink receiving layer formed in a transport path between the set position and the ink receiving layer forming means. 2. The inkjet printer according to 1. 3. The ink jet printer according to claim 1, further comprising a switching unit for switching whether or not to drive the ink receiving layer forming unit. 4. The apparatus according to claim 1, wherein the switching unit drives the ink receiving layer forming unit in response to detecting that the sensor is a recording sheet having no ink receiving layer formed thereon. The inkjet printer according to claim 3. 5. The ink receiving layer forming means includes: a container accommodating an ink receiving layer material; an application roller provided opposite an ink receiving layer material outlet of the container; and an application roller and the transport path. 5. An ink receiving layer forming roller pair comprising a pressure roller urged toward the application roller and disposed so as to be opposed to each other with a pinch therebetween.
The inkjet printer according to any one of the above. 6. The recording paper according to claim 1, wherein the recording paper is a long body wound in a roll shape and is set at the set position so as to be able to be fed out. Inkjet printer. 7. The ink jet printer according to claim 1, further comprising a cutter section for cutting recording paper to a required size on a downstream side of the printing section.