JP2002067294A - Ink-jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording device capable of making the recording medium evenly transparent, achieving miniaturization of the device and recording an image at a high speed at the time of the transparentizing treatment of the ink receiving layer by heating and pressuring a sheet-like recording medium having an ink receiving layer containing thermoplastic resin particles in the surface layer. SOLUTION: An ink-jet recording device comprising a recording head 3 for recording by ejecting an ink onto a sheet-like recording medium 1 having an ink receiving layer containing thermoplastic resin particles, a heating and pressuring means 4 for the transparent treatment of the ink receiving layer of the recording medium by heating and pressuring the recording medium, a recording medium conveying means for conveying the recording medium 1 after a recording operation by the recording head 3 to the heating and pressuring means 4, and a recording medium conveyance path capable of forming sag of the recording medium 1 between the recording head and the hearting and pressuring means 4, wherein the recording medium 1 is conveyed at a high speed to a position whereat the next ink ejection is executed without the recording operation by the recording head 3 in the case printing data corresponding to a value without ink ejection are provided successively, is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus, and more particularly, to a recording medium having an ink receiving layer containing thermoplastic resin particles on its surface layer, by performing recording by discharging ink, and then applying heat and pressure. The present invention relates to an ink jet recording apparatus in which a recording medium is heated and pressed by means.

[0002]

2. Description of the Related Art An ink jet recording system for recording an image by ejecting ink in the form of fine droplets onto a recording surface of a recording medium has been improved in recent years with high image quality approaching that of silver halide photography and cost reduction of the apparatus. Has become possible and has spread rapidly.

[0003] In the ink jet recording, a surface layer (image recording surface side) is provided for the purpose of imparting gloss to the surface of a recording medium on which an image is recorded, preventing bleeding of the image due to contact with water, and improving abrasion resistance. An image is recorded and formed using a recording medium having an ink receiving layer containing thermoplastic resin particles, and thereafter, the thermoplastic resin particles in the ink receiving layer are melted and smoothed by heating and pressing the recording medium, A method for making the ink receiving layer transparent has been proposed.

[0004]

In such a technique,
The recording medium on which the image has been recorded by the recording head is conveyed to the heating and pressing means by the conveying means in order to make the ink receiving layer transparent. As the heating / pressing means, for example, a heating roller having a built-in heating element is used, and while the recording medium is being conveyed, it is heated and pressed by the heating roller in the process to make the ink receiving layer transparent.

At this time, it is desired that the ink receiving layer be made transparent uniformly over the entire surface of the recording medium. For this purpose, it is necessary to convey the recording medium at a constant speed by the heating and pressurizing unit. However, the transfer speed of the recording medium during image recording by the recording head and the conveying speed of the recording medium by the heating and pressurizing unit are different. If there is a difference, it is difficult to perform the heating and pressurizing treatment uniformly at a constant speed.

In order to cope with this, by setting the distance between the recording head and the heating and pressing means to be equal to or longer than the maximum length of the sheet-shaped recording medium, the heating and pressing after the image recording by the recording head is completed. When the process starts,
Since the distance between the recording head and the heating / pressing means is restricted, there is a problem that the degree of freedom of the device design is low and the size of the device is increased.

Accordingly, an object of the present invention is to provide a recording medium having an ink receiving layer containing thermoplastic resin particles on its surface layer, which is heated and pressed to make the ink receiving layer transparent. An object of the present invention is to provide an ink jet recording apparatus which can be downsized, can be downsized, and can record images at high speed.

[0008]

The object of the present invention is achieved by the following means.

According to a first aspect of the present invention, there is provided a recording head which performs recording by discharging ink on a sheet-shaped recording medium having an ink receiving layer containing thermoplastic resin particles, and a recording medium which is heated and pressurized. A heating and pressurizing unit for making the ink receiving layer of the recording medium transparent, a recording medium conveying unit for conveying the recording medium on which recording has been performed by the recording head to the heating and pressing unit, and the heating and pressurizing from the recording head. Between the means, a recording medium transport path on which a slack of the recording medium can be formed,
When print data corresponding to a value that does not eject ink is continuous, printing is not performed by the print head,
Next, there is provided an ink jet recording apparatus which conveys a recording medium at a high speed to a position where ink is to be ejected.

According to the present invention, the apparatus can be miniaturized, the image recording time can be reduced, and the print medium is conveyed at high speed because the print data corresponding to the value at which no ink is ejected continues. Even if this is done, the change in the conveying speed does not directly affect the conveying speed of the recording medium by the heating and pressing means, and the conveying speed of the recording medium by the heating and pressing means can be kept constant. Therefore, the effect of reducing the size of the apparatus, shortening the image recording time, and uniformly and transparently processing the ink receiving layer by the heating and pressing means can be satisfied.

The invention according to claim 2 is the ink jet recording apparatus according to claim 1, wherein the recording head is a linear recording head having a length corresponding to the width of a recording medium. According to the present invention, image recording can be performed at a higher speed by using a linear recording head.

[0012]

Embodiments of the present invention will be described below.

As shown in FIG. 6, the recording medium 1 mainly used in the ink jet recording apparatus according to the present invention has an ink receiving layer 1B containing thermoplastic resin particles on the surface of a support 1A. An ink solvent absorbing layer 1C having a void layer that adsorbs the ink solvent component after the coloring material and the ink solvent component are separated on the surface of the ink receiving layer 1B adjacent to the inside of the ink receiving layer 1B may be provided. .

As the support 1A, a support conventionally used as an ink jet recording medium can be used. For example, other than a paper support such as plain paper, art paper, coated paper and cast coated paper, etc. , A plastic support, a paper support coated on both sides with a polyolefin, and a composite support obtained by laminating these.

The thermoplastic resin particles contained in the ink receiving layer 1B include, for example, polycarbonate, polyacrylonitrile, polystyrene, polyacrylic acid, polymethacrylic acid, polyvinyl chloride, polyvinylidene chloride,
Examples include polyvinyl acetate, polyester, polyamide, polyether, copolymers thereof, and salts thereof.
The thermoplastic resin particles are appropriately selected in consideration of ink receptivity, glossiness of an image after fixing by heating and pressurizing, image fastness and releasability.

Regarding the ink receptivity, when the particle size of the thermoplastic resin particles is less than 0.05 μm, the separation of the pigment particles from the ink solvent in the pigment ink becomes slow, which leads to a decrease in the ink absorption speed. . If it exceeds 10 μm,
When coated on a support, it is not preferable from the viewpoint of the adhesiveness to the pigment ink solvent absorbing layer 1C adjacent to the ink receiving layer 1B and the film strength of the recording medium after coating and drying. For this reason, the preferred thermoplastic resin particle diameter is preferably 0.05
10 μm, more preferably 0.1 to 5 μm.

The thermoplastic resin particles forming the outermost layer exist in a dispersed state in a solvent such as water before coating and drying.
In the case of a single thermoplastic resin particle having no variation in the dispersed particle size, the particles are packed in the closest dense hexagon by drying after coating to form a single particle layer, and the porosity at that time is about 26%. It is.
However, thermoplastic resin particles are usually polydisperse, and the porosity changes depending on the state of aggregation of the thermoplastic resin particles. In addition, the size of the formed void depends on the particle size of the thermoplastic resin particles.

The coating thickness on the support 1A is as follows.
0.1 to 10 μm is preferable, and more preferably 0.5 to
7 μm.

The criteria for selecting the thermoplastic resin particles include the glass transition point (Tg). If the Tg is lower than the coating and drying temperature, for example, the coating and drying temperature during the production of the recording medium is already higher than the Tg, and the voids due to the thermoplastic fine particles through which the ink solvent permeates disappear. When Tg is equal to or higher than the temperature at which the support 1A is denatured by heat,
In order to form a melt film after inkjet recording with a pigment ink, a fixing operation at a high temperature is required, which causes problems on the load on the apparatus and the thermal stability of the support 1A. The preferable Tg of the thermoplastic resin particles is 50 to 150 ° C., and this temperature Tg is set as a target temperature range in the temperature control in the heating and pressurizing means of the ink jet recording apparatus as described later.

The ink solvent absorbing layer has an ink solvent absorbing ability, which is exhibited by incorporating inorganic fine particles into the ink solvent absorbing layer. Examples of the inorganic fine particles used for this purpose include light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc hydroxide, zinc sulfide, Zinc carbonate, hydrotalcite, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica,
Examples include white inorganic pigments such as colloidal silica, alumina, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, zeolite, and magnesium hydroxide.

The average particle size of the inorganic fine particles can be determined by observing the fine particles themselves or the fine particles that have appeared on the cross section or surface of the void-type pigment ink solvent absorption layer with an electron microscope, and calculating the average particle size of 100 arbitrary particles. It is obtained as a simple average (number average). Here, the particle size of each fine particle is represented by a diameter assuming a circle equal to the projected area.

As the inorganic solid fine particles, it is preferable to use inorganic solid fine particles selected from fine particle silica, colloidal silica and alumina or alumina hydrate synthesized by a gas phase method. Alumina or alumina hydrate may be crystalline or non-crystalline, and may have any shape such as irregular particles, spherical particles, and acicular particles. At present, fine particle silica synthesized by such a gas phase method is commercially available, and there are various types of Aerosil manufactured by Nippon Aerosil Co., Ltd. as commercially available fine particle silica.

The average particle size of the inorganic fine particles is not particularly limited, but is preferably 100 nm or less, and the most preferable average particle size for forming the void layer differs depending on the compound. For example, in the case of the above-mentioned fumed silica, it is most preferable that the average particle diameter of the primary particles of the inorganic fine particles dispersed in the state of the primary particles (the particle diameter in the dispersion state before coating) is 4 to 20 nm. It can be preferably used.

The ink ejected from a recording head described later toward the ink receiving layer 1B of the recording medium 1 is absorbed by the ink receiving layer 1B and the ink solvent absorbing layer 1C, and an image is recorded. In the recording medium 1 on which an image is recorded in this manner, the thermoplastic resin particles contained in the ink receiving layer 1B are melted and smoothed by heating and pressurizing the ink receiving layer 1B on the surface, Being transparent, the recording medium 1
A transparent protective layer is formed on the surface of the substrate.

FIG. 1 is a schematic structural view of an ink jet recording apparatus according to the present invention.

The recording medium 1 is a sheet-shaped recording medium which has been cut into a suitable size in advance. The recording medium 1 is supplied by a recording medium supply means (not shown), and is conveyed rightward by a recording medium conveying means 2. I have.

The recording medium conveying means 2 has a first conveying roller 21, a second conveying roller 23, and a third conveying roller 25 from the upstream side, respectively.
23 and 25 are independently driven to rotate by driving means (transport motor) (not shown).

The recording medium 1 is applied to each of the transport rollers 21, 23, 25 corresponding to each of the transport rollers 21, 23, 25.
1st press roller 2 for pinching between
2, a second pressing roller 24 and a third pressing roller 26 are disposed, and the recording medium 1
In the state of being sandwiched between the holding rollers 3, 25 and the pressing rollers 22, 24, 26, the rotation of the respective conveying rollers 21, 23, 25 causes the recording head 3 (described later) to rotate in the right direction ( (Scanning direction).

The recording head 3 includes a pair of a first conveying roller 21 and a first pressing roller 22 and a pair of a second conveying roller 23 and a second pressing roller 22.
It is arranged between the pair of holding rollers 24. As shown in FIG. 2, the recording head 3 is movably attached to a scanning guide 31 erected in the width direction of the recording medium 1 so as to be substantially perpendicular to the conveying direction of the recording medium 1, and a driving unit (not shown) (Carriage motor) by the scanning guide 31
Along the main scanning direction.

The recording head 3 includes, for example, Y (yellow), M (magenta), C (cyan), and K (black).
And the like, and a plurality of ink tanks storing inks of respective colors, etc., are ejected at predetermined timing in accordance with image data, thereby cooperating with the conveyance of the recording medium 1 by the conveyance means 2. Then, a predetermined image is recorded and formed on the recording surface of the recording medium 1.

The heating and pressurizing means 4 is disposed downstream of the recording head 3 so as to heat and press the recording medium 1 on which an image has been recorded by the recording head 3. A pressure roller 42 for sandwiching the medium 1 between the medium 1 and the heating roller 41 is provided.

The heating roller 41 is a hollow roller, is configured to be rotatable by driving means (heating roller motor) (not shown), and is a heating element 43 such as a halogen lamp heater, a ceramic heater, or a nichrome wire as a heat source. The heating roller 41 is heated by the heat of the heating element 43. The heating roller 41 is used for the heating element 4.
The recording medium 1 is preferably formed of a material having a high thermal conductivity so that the recording medium 1 can be efficiently heated by the heat generated from the metal roller 3, and a metal roller is preferably used. The surface is preferably coated with a fluororesin in order to prevent contamination by ink when the recording medium 1 is heated and pressed. In addition, a silicon rubber roller coated with heat-resistant silicon can be used.

The pressing roller 42 is urged by an urging means (not shown) so as to press the recording medium 1 against the heating roller 41 with a predetermined pressing force. 1 is pressurized.

In the nip area formed between the pressure roller 42 and the heating roller 41, it is possible to make the recording medium 1 come into pressure contact with the surface of the heating roller 41 with a large contact area to increase the heating / pressing time. It is desirable to have a certain width so that it can be performed. Therefore, the pressure roller 42
It is preferable that at least the surface has elasticity. For example, an elastic roller having a metal shaft surface coated with elastic rubber is preferably used.

Reference numeral 5 denotes a temperature sensor disposed close to the surface of the heating roller 41. The temperature sensor detects the temperature of the surface of the heating roller 41 and controls the amount of heat generated by the heating element 43 by temperature control means (not shown). The heating roller 41 is maintained in a predetermined temperature range.

In the present invention, the recording medium 1 is disposed between the first transport roller 21 and the first pressing roller 22 and the second transport roller 2.
3 and the second pressing roller 24, between the third conveying roller 25 and the third pressing roller 26, and between the heating roller 41 and the pressure roller 42. Therefore, a recording medium transport path is formed between these, and the recording medium 1 on which a predetermined image has been recorded by the recording head 3 is heated and pressed by the rotation of the transport rollers 21, 23 and 25. Transported to

The heating / pressurizing means 4 holds the recording medium 1 between the heating roller 41 and the pressure roller 42, and conveys the recording medium 1 at a predetermined constant speed by rotating the heating roller 41.
In the process, the recording medium 1 is heated and pressurized to melt and smooth the thermoplastic resin particles in the surface ink receiving layer to make it transparent.

Next, the electrical configuration of the ink jet recording apparatus according to the present invention will be described with reference to the block diagram shown in FIG. In the drawings, the description of the already-described reference numerals is omitted.

In the figure, reference numeral 100 denotes a host device, which is composed of a computer having image data to be recorded in an ink jet recording apparatus (parameters such as a recording size of an image, data of an image color-separated into YMCK, etc.). . The image data transmitted from the host device 100 is taken into the inkjet recording device via the interface unit 101.

Reference numeral 102 denotes an image memory for temporarily storing image data fetched from the host device 100; 103, a memory write controller for controlling writing of image data to the image memory 102; 104, an image memory for storing image data stored in the image memory 102; A memory read controller 105 for controlling reading;
A head driver for driving and controlling the ejection of ink from the recording head 3 in accordance with image data read from the image memory 102 by the memory read controller 10
4 is an ejection data detecting means for detecting whether or not the image data read from the image memory 102 includes print data to eject ink.

Reference numeral 107 denotes a first conveyance motor for driving the first conveyance roller 21 to rotate, 108 denotes a second conveyance motor for driving the second conveyance roller 23 to rotate, and 109 denotes a third conveyance motor for driving the third conveyance roller 25 to rotate. Reference numeral 110 denotes a heating roller motor for driving the heating roller 41 to rotate, and 111 denotes a carriage motor for moving and scanning the recording head 3 along the scanning guide 31.

Reference numeral 112 denotes the host device 1 that controls the interface unit 101, the image memory 102, the memory write controller 103, and the memory write controller 104.
00, the head driver 105, the first conveyance motor 107, the second conveyance motor 108, and the third conveyance motor 10 according to the image data, the ejection data detection means 106, and the temperature of the heating roller from the temperature sensor 5.
9, a CPU that controls the heating roller motor 110, the heating element 43, and the carriage motor 111.

Next, the operation of the ink jet recording apparatus according to the present invention will be described.

The sheet-shaped recording medium 1 is nipped and conveyed between a first conveying roller 21 and a first pressing roller 22, and an image is recorded by the recording head 3 when the recording head 3 reaches a predetermined recording start position. You. The recording medium 1 during image recording is intermittently driven at a predetermined speed each time the recording head 3 scans, with the first conveyance roller 21 and the second conveyance roller 23 being substantially synchronized with each other. 1 is intermittently conveyed on a conveying path at a predetermined speed.

On the other hand, during the image recording, the third transport roller 2
5 is controlled to stop the rotation drive. As a result, the recording medium 1 that has passed between the second conveying roller 23 and the second pressing roller 24 is not conveyed by the third conveying roller 25, and the leading end of the recording medium 1 contacts the third conveying roller 25 and the third pressing roller 26. And the recording medium 1 is further conveyed by the rotation of the second conveying roller 23, and the second conveying roller 23 and the second pressing roller 24
Of the recording medium 1 is formed in the recording medium conveying path between the pair of the third conveying roller 25 and the third pressing roller 26. After the recording medium 1 is conveyed until the formed slack 1a reaches a predetermined amount to perform image recording, the third conveying roller 25 is driven to rotate and the recording medium 1 is moved to the third pressing roller 26.
And transported to the heating and pressing means 4.

At this time, by making the average speed of the intermittent conveyance of the recording medium 1 during image recording by the first conveyance roller 21 and the second conveyance roller 23 substantially equal to the conveyance speed of the heating / pressurizing means 4, The pressurizing means 4 can convey at a constant speed.

Thus, the heating and pressurizing process of the recording medium 1 by the heating and pressing means 4 is not affected by the intermittent conveyance of the recording medium 1 during image recording, and the recording medium 1 is heated at a constant speed. Pressure treatment can be performed, and the ink receiving layer can be uniformly and transparently processed without unevenness. Further, the slack 1 of the recording medium 1 is set between the recording head 3 and the heating / pressing means 4.
Since a can be formed, the distance between the recording head 3 and the heating and pressing means 4 can be reduced, and the size of the apparatus can be reduced.

In the present invention, the image memory 102
Ejection data detection means 1
When the print data corresponding to the value at which no ink is ejected detected at step 06 is continuous, the image recording by the recording head 3 is not performed, the first transport roller 21 and the second transport roller 23 are driven to rotate, and Is controlled so that the recording medium 1 is conveyed at a high speed to a position where the liquid is to be ejected.

Here, the printing data corresponding to the value at which no ink is ejected is determined to be continuous.
This is a case where the entire print data corresponding to one scan is a value that does not eject ink.

For example, as shown in FIG. 7, when the print head scans in the direction of the arrow (right direction in the figure) in the figure, if there is no place where ink should be ejected over the entire width of the print medium 1, this There is no point in performing such a scan. In such a case, if the recording medium 1 is conveyed to the next recording position without scanning the scanning head 3, the recording time can be reduced.

The flow of the transport control will be described with reference to FIG.

The CPU 112 controls the memory read controller 104 to read the image data stored in the image memory 102, and checks the data for one scan of the print head 3 by the ejection data detecting means 106 (S
1) It is determined whether or not there is data for ejecting ink in the data for one scan (S2). As a result, when there is data for ejecting ink in the data for one scan, the recording head 3 is scanned to record an image for one scan (S3), and then the recording medium is conveyed for one scan (S3).
4).

When there is no data for ejecting ink in the data for one scan by the ejection data detecting means 106,
The print medium 3 is conveyed by one scan without scanning the print head 3 (without printing) (S4). Thereafter, if there is the next image data, the process returns to S1 and the above processing is repeated.

At this time, since the recording medium 1 can form the slack 1a before the heating and pressurizing means 4 as described above, since the printing data corresponding to the value at which no ink is ejected continues, the recording medium 1 is continuously moved. The transport speed does not affect the transport speed of the recording medium 1 by the direct heating / pressurizing unit 4 and the transport speed of the recording medium 1 by the heating / pressurizing unit 4 is maintained constant. It is possible.

As a result, the image recording time can be shortened, and the heating and pressurizing means 4 can evenly make the ink receiving layer transparent. Further, by ending the image recording earlier, the transfer of the image data from the host computer is also finished earlier, and the host computer can be released earlier. In addition, in preparation for the next recording, the recording head can be cleaned, clogging prevention processing can be performed, and feeding of the next recording medium can be started quickly.

In the above description, the image recording is performed while the recording medium 1 is intermittently conveyed by using the recording head 3 of the reciprocal scanning type. However, the line recording shown in FIG. It is also preferable to use the head 32.
The linear recording head 32 has a length corresponding to the width of the recording medium 1 and extends in the width direction of the recording medium 1 (a direction orthogonal to the transport direction of the recording medium 1). While conveying at a constant speed, ink is ejected in the width direction to record an image.

In the linear recording head 32, the image data read from the image memory 102 includes
When print data corresponding to the value at which ink is not ejected detected by the ejection data detecting means 106 is continuous, the image recording by the recording head 32 is not performed, and the first transport roller 21 and the second transport roller 23 are driven to rotate. If the recording medium 1 is conveyed at a high speed to a position where ink is to be ejected next, image recording can be completed quickly, while the conveying speed of the recording medium 1 by the heating and pressing means 4 is maintained constant. Thus, the ink receiving layer of the recording medium 1 can be transparently processed without unevenness.

[0058]

According to the present invention, when a sheet-shaped recording medium having an ink receiving layer containing thermoplastic resin particles on its surface layer is heated and pressurized to make the ink receiving layer transparent, the recording medium is uniformly transparent. It is possible to provide an ink jet recording apparatus which can be downsized, can reduce the size of the apparatus, and can perform high-speed image recording.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an ink jet recording apparatus according to the present invention.

FIG. 2 is a configuration diagram illustrating an example of a recording head.

FIG. 3 is a block diagram for explaining an electrical configuration of the ink jet recording apparatus according to the present invention.

FIG. 4 is a flowchart of the transport control according to the present invention.

FIG. 5 is a configuration diagram showing another example of a recording head.

FIG. 6 is a cross-sectional view illustrating a laminated structure of a recording medium.

FIG. 7 is a schematic configuration diagram of a recording head and a recording medium for describing a recording state.

[Explanation of symbols]

 1: recording medium 2: recording medium conveying means 21: first conveying roller 22: first pressing roller 23: second conveying roller 24: second pressing roller 25: third conveying roller 26: third pressing roller 3: recording head 31: scanning guide 32: linear recording head 4: heating and pressurizing means 41: heating roller 42: pressure roller 43: heating element 5: temperature sensor 100: host device 101: interface unit 102: image memory 103: memory light controller 104: Memory read controller 105: Head driver 106: Discharge data detecting means 107: First transport motor 108: Second transport motor 109: Third transport motor 110: Heating roller motor 111: Carriage motor 112: CPU

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2C056 EA01 EB58 EC12 EC31 FA13 HA29 HA45 HA46 2C058 AB17 AC07 AC11 AD01 AE10 AF20 AF23 GA08 GB19 GB20 GB47 GE22 GE24 2C059 AA26 AA32 AA39 AA76 BB07 BB11 3F053 HA08 H07LB08B

Claims (2)

[Claims] 1. A recording head for performing recording by discharging ink on a sheet-shaped recording medium having an ink-receiving layer containing thermoplastic resin particles, and an ink-receiving layer of the recording medium by heating and pressing the recording medium. Heating and pressurizing means for making the recording medium transparent, a recording medium conveying means for conveying the recording medium on which recording has been performed by the recording head to the heating and pressing means, and between the recording head and the heating and pressing means, A print medium transport path on which a slack of the print medium can be formed, and when print data corresponding to a value that does not discharge ink continues, printing by the print head is not performed, and ink should be discharged next. An ink jet recording apparatus for conveying a recording medium to a position at a high speed. 2. An ink jet recording apparatus according to claim 1, wherein said recording head is a linear recording head having a length corresponding to a width of a recording medium.