JPH07329413A - Ink jet recording method - Google Patents

Abstract

PURPOSE:To provide an ink jet recording method preventing such a phenomenon that paper to be recorded is largely curled when a large amt. of a recording soln. is applied to the paper to be recorded within a short time to perform recording. CONSTITUTION:In an ink jet recording method wherein small liquid droplets of a recording soln. are emitted from emitting orifices corresponding to data to be recorded to be bonded to the coating layer 32 of a material to be recorded obtained by providing the coating layer 32 on the surface of base paper 31 to record a desired image on the material to be recorded, a damage or hole 35 of which the depth does not reach the coating layer 32 is formed to the rear surface of the base paper 31 of the material to be recorded before recording or simultaneously with recording.

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 method, and more particularly to improvement of a multicolor ink jet recording method.

[0002]

2. Description of the Related Art Ink jet recording methods include various recording liquid ejection methods (for example, an electrostatic suction method, a method in which a piezoelectric element is used to mechanically vibrate or displace the recording liquid, and the recording liquid is heated and foamed to adjust its pressure Depending on the method used, etc., small droplets of recording liquid (ink) are generated from the discharge port and are made to fly, and some or all of them are attached to a recording material such as paper to record characters, figures, etc. Is to
It is attracting attention as a recording method that generates less noise, has a low running cost, can be easily downsized, and can perform high-speed printing and multicolor printing, and it is used in printers, copiers, facsimiles, and the like.

As a recording liquid for ink jet recording,
Water-based materials are mainly used in terms of safety and printability, and paper and film are generally used as recording materials. When recording with liquid ink, it is generally necessary that the ink does not blur more than necessary on the recording material and the dots do not blur, and that the ink dries quickly after it adheres to the recording material. Is desirable. Therefore, the recording material is generally a base paper coated with an ink absorbing layer containing a pigment or the like.

Particularly in a color ink jet recording system using two or more colors of ink, the recording material is: 1) The ink is quickly absorbed by the recording material, and even if there are overlapping inks of different colors, they adhere afterwards. Do not mix the formed ink with the previous ink, disturb the dots, or flow out. 2) The ink droplets do not spread on the recording material and the dot diameter does not become larger than necessary. 3) Ink dots It is necessary to satisfy various characteristics such as a high density, a dot shape close to a perfect circle, and 4) little dimensional fluctuation (wrinkle, elongation, curl, etc.) of the recording material.

However, the conventionally used recording material cannot satisfy these various characteristics, and thus the conventional color ink jet recording method cannot meet these requirements.

[0006]

That is, when a large amount of ink is ejected onto the recording paper in a short time, the ink which cannot be completely absorbed by only the coating layer reaches the surface layer of the base paper. Then, a difference in water distribution is created between the surface layer and the lower layer of the base paper, and if the ink is dried as it is, a large curl will occur. Further, if the amount of ink to be ejected is reduced in order to avoid this phenomenon, there is a problem that the print density is lowered and the image quality is lowered.

The present invention has been made to solve the above-mentioned problems, and even if a large amount of recording liquid is jetted onto a recording paper in a short time for recording, the recording paper causes a large curl due to the recording. The present invention provides a non-inkjet recording method.

[0008]

According to the present invention, the above object can be achieved by forming a scratch or a hole on the back side of the base paper of a recording material having a coating layer on the surface of the base paper. I knew it was.

That is, according to the present invention, small droplets of the recording liquid are ejected from the ejection port according to the data to be recorded, and the small droplets are formed on the covering layer of the recording material having the covering layer provided on the surface of the base paper. In an inkjet recording method for recording a desired image on a recording material by depositing droplets, the depth does not reach the coating layer on the back surface of the base paper of the recording material before or at the same time as recording. The inkjet recording method is characterized by forming such scratches or holes.

Embodiments of the present invention will be described below. First, a recording material used in the method of the present invention will be described with reference to the drawings.

FIG. 2 is a perspective view showing the structure of a recording material in which a coating layer is provided on the surface of a base paper. In FIG.
Is a base paper, and 32 is a coating layer, and this layer mainly acts as an absorbing layer for the recording liquid.

The coating layer 32 contains casein and styrene-butadiene rubber, which are water-based binders, and at least synthetic silica. Other pigments that can be used in combination with the synthetic silica include, for example, kaolin, talc, calcium carbonate, barium sulfate, aluminum hydroxide, titanium dioxide, zinc oxide, satin white, diatomaceous earth, acid clay, zeolite, colloidal silica. , Organic pigments and the like. At this time, the content of synthetic silica in the pigment in the coating liquid is preferably 80% by weight or more. Further, if necessary, a pigment dispersant, a water retention agent, a thickener, an antifoaming agent, a release agent, a colorant, a water-proofing agent, a wetting agent, a fluorescent dye, an ultraviolet absorber, etc. are appropriately mixed in the coating liquid. There are also things to do.

To form the coating layer 32, the coating solution is coated on the base paper 31 by a known method (roll coating method, blade coating method, air knife coating method, etc.). Usually, after coating, the casein in the coating liquid is solidified by a solidification method, and for drying, a method is used in which the coating layer 32 is pressure-bonded to the heated finished surface and dry-finished.

According to an embodiment of the present invention, before the desired image is ink-jet recorded on the coating layer of the recording material formed as described above, the depth of the recording medium on the back surface of the base paper is reduced. A scratch or a hole that does not reach the coating layer is formed, and recording is performed using such a scratch or hole formed on the back surface of the base paper as a recording material for inkjet recording. In another embodiment,
The formation of the scratches or holes on the back surface of the base material of the recording material is performed in the recording apparatus at the same time as the recording of the image on the recording material by the inkjet recording method. A preferable example of the former embodiment is that, as shown in FIG. 3, a step 33 for making a scratch or a hole on the back surface of the base paper is provided before the cutting step 34 when the completed recording material is cut into a small size. Is. The step 33 of making a scratch or a hole is a cutting step 34.
However, if it is provided before the cutting step, it is not necessary to prepare various patterns of scratches or holes depending on the paper size.

When a scratch or a hole is formed on the back surface of the base paper of the recording material, it is preferable to make it parallel to the flow direction of the paper making of the base paper in both of the above embodiments. This will be described with reference to FIG. 4, which is a cross-sectional view of the recording material. Here, the paper surface and the vertical direction are the flow directions of the papermaking. Figure 4
When the ink 37 is struck on the surface of the coating layer 32 as shown in (a), the ink diameter slightly expands, but the ink permeates mainly in the depth direction and cannot be absorbed by the coating layer alone.
Reaches the surface layer of the base paper 31 as shown in FIG.
The back side of the base paper remains dry. Since many pulp fibers are arranged parallel to the flow direction of the papermaking, when the ink dries, the coating layer side shrinks as shown in FIG. 4 (c),
With this inside, curl perpendicular to the paper flow direction,
The base paper 31 side is relatively stretched. By providing the scratches or holes in parallel with the flow direction of the paper making of the base paper, even when the ink is ejected as shown in FIG. 4, the relative elongation of the base paper 31 is cut and the curl after printing is curled. Reduce.

The width of the holes or scratches provided on the back surface of the base paper is preferably as small as 0.5 mm or less so as not to be noticeable, and the depth should not reach the surface of the base paper. When the scratch reaches the surface of the base paper, the strength of the paper is weakened, and when the coating layer is damaged, the ink absorbing ability is deteriorated. Also, the greater the number of rows of holes or scratches provided in parallel with the flow direction of the papermaking of the base paper, the greater the curl reduction effect, but in order to maintain the strength of the paper, it is cut into a small size for recording. For the material, there may be at least one row of holes or scratches parallel to the flow direction of the paper making of the base paper.

[0017]

EXAMPLES Examples of the above-described embodiments of the present invention will be described below with reference to the drawings.

(Example 1) When a recording material having a coating layer on the surface of a base paper is cut into a small size, the back surface of the base paper is scratched before the cutting step 34 as shown in FIG. Step 33 was provided. The recording material flows in the flow direction of the base paper. In step 33, the blade of the cutter is arranged so as to face the back surface of the base paper, and as shown in FIG. 1B, the scratch 35 is formed on the back surface of the base paper 31 so that the depth thereof does not reach the coating layer 32. Formed. Scratched recording material 3
4 was cut, and a recording material having a scratch 35 on the back surface of the base paper in parallel with the flow direction of the paper making of the base paper was obtained as shown in FIG.

Using the recording material thus obtained, an ink jet recording apparatus was used to form a recording layer on the coating layer.
When ink is ejected as shown in FIG. 4A, FIG.
The curl phenomenon after printing as shown in (1) was remarkably reduced as compared with the case of printing using a recording material having no such scratches formed on the back surface of the base paper.

(Embodiment 2) In step 33 shown in FIG. 3, instead of the blade of the cutter of Embodiment 1, a needle is arranged so as to face the back surface of the base paper, and the recording material is a base paper flow. A row of holes was formed on the back surface of the base paper 31 so that the depth of the needle did not reach the coating layer 32 due to the needle moving up and down when flowing in the direction. The recording material with the row of holes is cut in a cutting step 34.
The recording material, which is cut with, and has rows of perforations 36 like perforations formed on the back surface of the base paper in parallel with the flow direction of the paper making of the base paper as shown in FIGS. Was obtained.

When ink jet printing was performed using this recording material in the same manner as in Example 1, the curling phenomenon after printing was substantially the same as in Example 1. Further, this embodiment has an advantage that the row of holes on the back surface of the base paper is less conspicuous than in the first embodiment.

(Embodiment 3) The recording material is cut as it is without passing through a step of making a scratch or a hole, and at the same time when an image is recorded by the ink jet recording method, a scratch or a hole is formed on the back surface of the base paper of the recording material. It is an example of a mode to form.

FIG. 6 is a perspective view showing the ink jet recording apparatus used in this embodiment, and FIG. 7 is a sectional explanatory view thereof. First, the overall configuration will be described. This device comprises a reading device R and a recording device P. The reading device R is configured such that the reading means 1 is provided on the reading carriage 2 and the carriage 2 can reciprocate in the main scanning direction (direction of arrow a). The carriage 2 is attached to the reading unit 3, and the unit 3 is configured to be capable of reciprocating in the sub-scanning direction (arrow b direction).

Therefore, when the original 5 is placed with the original surface facing down on the original table glass 4 attached to the upper surface of the apparatus, the original 5 is fixed and set by the cover 6, and the copy switch (not shown) is pushed, the carriage 2 Moves in the main scanning direction to read one line of a document, and transmits the information to a control system (not shown) via the signal cable 7. When the reading of one line is completed as described above, the carriage 2 is returned to the home position, the reading unit 3 moves in the sub-scanning direction by one line, and the subsequent lines are read in the same manner as described above. .

The recording device P is constructed such that the recording means 8 is mounted on the recording carriage 9 and the recording material 11 is conveyed to the position of the recording means 8 by the conveying means 10.

Therefore, when the read signal from the reading device R is transmitted through the signal cable 7, the recording material 1
When 1 is conveyed by the conveying means 10 in the direction of arrow c and is conveyed to the recording position, the recording carriage 9 reciprocates in the direction of arrow d in FIG. 6, and the recording means 8 is synchronized with this movement.
Drive according to the image signal to record an image on the recording material 11. When the recording of one line is completed, the recording material 11
Is conveyed in the direction of arrow c for one line, recording is similarly performed, and the recording material 11 after recording is ejected to the ejection tray 12.

The transporting means 10 is for transporting the recording material 11 for recording. As shown in FIG. 7, the transporting means 10 has a cassette 10a detachably attached to the lower part of the apparatus. A plurality of recording materials 11 are stacked and stored. The recording material 11 is a pickup roller 10b.
And a separation claw 10a provided at the tip of the cassette 10a
_The sheet is separated and fed one by one in the direction of arrow c by ₁ and is conveyed by a pair of conveying rollers 10c and 10d arranged on the upstream and downstream sides of the recording head 8b in the conveying direction.

Reference numeral 18 shown in FIG. 7 is a means for forming scratches or holes at the same time as the recording of an image by the ink jet recording method on the back surface of the base paper of the recording material in this embodiment, such as a blade or a needle of a cutter. Is placed upside down so that it is brought into contact with the back surface of the base paper of the recording material at the time of conveyance, and the same scratches as in Example 1 are made. According to the second embodiment, the needle is arranged as the means 18 so as to face the back surface of the base paper, and the needle moves up and down when the recording material passes the image recording position. It was also possible to form a row of perforations similar to those in Example 2 on the back surface of the base paper.

As described above, by using the ink jet recording apparatus having the above-described structure including the means 18, the recording material 11 having a coating layer on the surface of the base paper is used, and the recording material 11 is used as a base paper. When an image is recorded while being conveyed in the flow direction, the curl phenomenon of the recording material due to the image recording is similarly recorded using the same recording material by the ink jet recording apparatus having no means 18. It was remarkably reduced as compared with the case of performing.

[0030]

As described above, according to the present invention, recording liquid is formed by forming small droplets of the recording liquid and adhering these small droplets onto the coating layer of the recording material provided with the coating layer on the base paper. In the inkjet recording method to be performed, a curl of the recording material after inkjet recording is reduced without damaging the coating layer by forming a scratch or a hole on the back side of the base paper of the recording material before or simultaneously with recording. There is an effect.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a recording material used in the present invention, in which (a) shows a back surface thereof and (b) shows a cross section thereof.

FIG. 2 is a diagram showing a structure of a recording material.

FIG. 3 is an explanatory diagram of a flow up to cutting of a recording paper according to an embodiment of the present invention.

FIG. 4 is an explanatory diagram of a curl phenomenon of a recording material accompanying recording, where (a) shows a state where ink is ejected on the surface,
(B) shows where the ink reaches the surface of the base paper, and (c) shows where the ink is dried and the recording material is curled.

5A and 5B are diagrams showing another example of a recording material used in the present invention, in which FIG. 5A shows a back surface thereof and FIG. 5B shows a cross section thereof.

FIG. 6 is a perspective view for explaining an inkjet recording apparatus used in another embodiment of the present invention.

7 is a cross-sectional view of the inkjet recording apparatus of FIG.

[Explanation of symbols]

 R Reader P Recording device 10 Conveying means 11 Recording material 18 Means for forming scratches on the back side of base paper 31 Base paper 32 Covering layer 33 Process for forming scratches on the back side of base paper 34 Cutting process 35 Scratches 36 Holes 37 Ink

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Claims (6)

[Claims] 1. A small droplet of a recording liquid is discharged from a discharge port according to data to be recorded, and the small droplet is attached onto a covering layer of a recording material having a covering layer on the surface of a base paper. In an ink jet recording method for recording a desired image on a recording material by such a method, scratches or a depth of which does not reach the coating layer are formed on the back surface of the base paper of the recording material before or simultaneously with recording. An ink jet recording method comprising forming a hole. 2. The ink jet recording method according to claim 1, wherein the scratch or the hole is formed on the back surface of the base paper of the recording material before the recording of the image on the recording material. 3. The ink jet recording method according to claim 1, wherein the scratches or holes are formed on the back surface of the base paper of the recording material at the same time when the image is recorded on the recording material. 4. The ink jet recording according to claim 1, wherein the scratches or holes are formed on the back surface of the base paper of the recording material in parallel with the flow direction of the paper making of the base paper. Method. 5. The shape of the scratch or hole formed on the back surface of the base paper of the recording material in parallel with the flow direction of the paper making of the base paper is at least one straight line or perforation line. The inkjet recording method according to claim 4. 6. A small droplet of a recording liquid is discharged from a discharge port in accordance with data to be recorded, and the small droplet is attached onto a coating layer of a recording material having a coating layer on the surface of a base paper. In the ink jet recording apparatus used for recording a desired image on the recording material by this, on the back surface of the base paper of the recording material, at least 1 is provided in parallel with the flow direction of the paper making of the base paper.
An ink jet recording apparatus comprising means for forming a straight line or a perforated line of a book at the same time as recording at a depth that does not reach the coating layer.