JPS61219661A - Liquid jet recorder - Google Patents

Abstract

PURPOSE:To prevent a record (contamination) from being generated at parts other than desired parts, by providing an ink support with a sponge form ink- impregnated layer and an isolating layer for isolating an ink held in a multiplicity of holes from a recording medium. CONSTITUTION:When the ink support 4 comes to a recording part on a thermal head 2, a recording paper 3 and the ink support 4 are brought into close contact with each other by pressing the head 2 and a platen roller 1 against each other, whereby the ink infiltrated in the sponge form ink-holding layer 7 of the ink support 4 exudes to fill also the holes which have not been filled with the ink. When the support 4 thus filled with the ink comes into contact with a heating element 5 of the head 2, the element 5 is heated according to an image signal, and the ink contained in the hole is set into a bumping state, a bubble rapidly grows in the ink, and an ink droplet flies onto the recording paper 3, whereby a record dot is obtained. Since an ink-isolating space layer 8 of the ink support 4 is sufficiently thicker than the ink-holding layer 7, the ink contained in the hole not heated will not exude to adhere to the paper 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a liquid jet recording apparatus, which is a new electronic printing technology that performs recording by conveying liquid ink.

[Technical background of the invention and its problems]

Conventionally, there are the following thermal inkjet recording methods that perform recording by selectively ejecting ink using heat. One method is to instantaneously generate bubbles due to heat generated by a piezoelectric element or a heating resistor provided in a nozzle chamber, and the pressure of the generated bubbles forces ink out of an orifice (or nozzle). When the heating is stopped, the bubble contracts and draws the ink back. Then, some of the ink does not return and flies out, thereby creating a recording method (%
(Refer to Kosho 56-9429). This method is called an on-demand method in which ink is ejected only when necessary, and has the advantage of not wasting ink and recording speed is relatively high. However, on the other hand, the production of the recording head is complicated due to the drilling of nozzle holes and the arrangement of piezoelectric elements and heat-generating resistive elements in the ink chamber, and ink coagulation occurs when the device is stopped, resulting in clogging. Despite having the above-mentioned features, printers using the thermal inkjet recording method have not become popular because they have the biggest problem of causing malfunctions.

On the other hand, a recording device (Japanese Unexamined Patent Publication No. 51-13203
6) is disclosed. In this method, a heating resistor element is provided below the surface of the ink liquid to perform rapid heating to generate bubbles, and the impact caused by the destruction of the bubbles causes ink droplets to fly from the liquid surface to perform recording. Although this method essentially does not cause the problem of ink clogging, it causes environmental pollution (bad smell) due to ink evaporation and has many restrictions on the structure of the device. Furthermore, many problems remain, such as spillage of ink during transportation and movement, and difficulty in maintaining a constant distance between the ink surface and the heat generating part in terms of image quality.

In other words, the emergence of new recording technologies that have the advantages of low recording energy like inkjet recording, the ability to record on rough surfaces, and ease of handling like thermal transfer. It was something to wait for.

[Purpose of the invention]

The present invention has been made in response to the above requirements, and its purpose is to transport liquid ink using an ink support having multiple holes, and to eject the liquid ink using energy generated from a recording head. The present invention provides a new liquid jet recording device that records on a recording medium by using a liquid jet recording device, and in particular, even if recording is performed with the ink support and the recording medium in close contact, no recording (stains) will occur in unnecessary areas. The present invention provides a liquid jet recording device that does not cause

[Summary of the invention]

The present invention includes an ink support having multiple holes that holds liquid ink, and a recording head that selectively applies heat or an electric field to the ink held in the ink support. Alternatively, the ink held on the ink support is ejected by an electric field, and the ejected ink is placed on a recording medium that is arranged to sandwich the ink support, face a recording head, and press the ink support in close contact with the ink support. A liquid jet recording device that performs recording by adhering the ink, wherein the ink support has a spongy ink-impregnated layer and an isolation layer for isolating the ink held in the multiple holes from the recording medium. A liquid jet recording device is provided.

〔Effect of the invention〕

According to the present invention, since no nozzles are used at all, nozzle clogging, which has been a problem in the past, is completely eliminated. Since it is compatible, the position of the recorded image is not affected at all.

In addition, since recording is performed in close contact between the ink support that retains the ink and the recording medium, the ideal position is the point where the ink is actually ejected and attached to the recording medium, and the ink retention layer of the ink support Since it is made of a hydrophilic material such as a spongy substance, the ink oozes out from here when pressure is applied for close contact, and the ink acts to fill the unfilled holes.

[Embodiments of the invention]

An embodiment of the present invention will be described below in detail with reference to the drawings. First, the recording principle of the present invention will be briefly explained using FIG. A recording paper (not shown) is disposed at a position facing the thermal head (2), sandwiching the ink support (2). For example, this ink support (1) is made by etching a nickel plate made by electroforming to form a large number of holes. The ink support (1) then retains the liquid ink (hereinafter referred to as ink) in its pores before reaching the thermal head (1).

The ink held in this hole moves in the direction of the arrow in the figure.

The ink support (1) is brought into contact with a thermal head (1) comprising a plurality of heating elements (1). Here, the heating element @ selectively generates heat according to the image signal. The ink that comes into contact with this heating element trowel rapidly forms bubbles inside it and is discharged from the holes. (to) in the figure shows a state where the discharge is in progress. The ink ejected in this manner is transferred to the recording paper facing the thermal head (A) through the ink support (2), thereby obtaining recording dots.

In the figure (to) shows the holes after ink is ejected. Further, the ink support (7) advances in the direction of the arrow in the figure, and the above recording process is repeated to obtain a desired image on the recording paper.

This method of transporting ink by providing a large number of holes in the ink support (1) is a recording method that does not use nozzles, in which one pixel is formed by ink emitted through a plurality of holes. In other words, since nozzles are not used, clogging is virtually non-existent. Even if clogging occurs for some reason, it will not affect the majority of printing because one pixel corresponds to multiple holes. Furthermore, since the ink support (3) always carries fresh ink, it is a new recording method that eliminates recording errors caused by air bubbles in the ink.

Next, referring to FIG. 4, the overall configuration and operation of an embodiment of a liquid jet recording apparatus using the above-mentioned recording principle when used as a serial printer will be described. The recording paper) is wound around the platen roller (41). The axis of this platen roller (rotation of 411 (the recording paper is freely conveyed by platen roller 61) ) and a belt (41).The rotation of the platen roller 0D is performed together with the drive of the recording paper feed motor (6).On the other hand, the ink support body (described later) is connected to the belt (41) by the ink tank cassette (41). 4η is attached to the carriage throat,
It is removable.

The carriage rod to which the ink tank cassette 47) is attached is guided and moved by a shaft (c).

Pulley 61) provided on the shaft of the motor iron and carriage 1
4υ are connected by the belt 63, the movement of the carriage +48 is performed together with the drive of the motor (2). Also, an endless ink support (c) is wound up in the ink tank cassette +47), and new ink is sequentially fed out by this. A detailed explanation of this will be given later.

This ink support (c) is in contact with the thermal head group. The heating element of this thermal head selectively generates heat, creating bubbles in the ink. Recording is performed by causing the ejected ink to flow toward the recording paper and adhere to the recording paper. The ink support (Ile is wound up on reel 5.
4) is performed by rotation. As the reel rotates, the ink support is continuously supplied with new ink.

FIG. 5 is a diagram showing the principle of transporting ink within the ink tank cassette. The recording paper ■ is fed sequentially as the platen roller rotates. The ink application roller I33 and the auxiliary roller are connected to the ink support 19.
rotates so as to move in the direction of arrow A in the figure. first,
The ink support does not hold any ink at the position (marked) in the figure, but is coated with ink stored in the ink reservoirs 6 and 51 by the ink application roller 13. In the figure, the ink is held on the ink support (69).As the ink continues in the direction of arrow A, the ink is conveyed onto the heating element of the thermal head by the ink support II. The ink forms a protective film (not shown) on the thermal head.
□In contact with the heating element through. Then, this heating element is selectively heated in accordance with the signal, and the ink on the ink support II on this heating element suddenly bumps. The selectively heated and bumped ink adheres to the recording paper due to the cooperative relationship between the platen roller and the thermal head trowel, thereby forming the recorded image σ1. Further, the movement of the ink support II and the recording paper is synchronized with the signal from the thermal head, and the ink support device repeats the above process endlessly.

Next, the structure of the above-described ink support will be explained using the cross-sectional views of the recording portion shown in FIGS. 1(a) and 1(b).

In FIG. 1(a), the arrangement relationship is that the platen roller (
1) and the thermal head (2), a recording paper (8) is carried in between the thermal head (2) and the recording paper (8). (2) For example, a heating resistor (5
) is provided, and this heating resistor (5) is covered with a protective film (6).

FIG. 1(b) is an enlarged view of the portion of FIG. 1 (al).

The ink support (4) consists of an ink retaining layer (7) sandwiched between an ink isolation space layer (8) and an ink isolation layer (9).

This ink and the retaining layer (7) are made of paper that has ink affinity.
It is made of porous elastic sponge material like cloth. Both the ink-isolating space layer (8) and the ink-isolating layer (9) are materials that exhibit ink-incompatibility. In the former ink isolation space layer (9), the recording paper (8) is the ink support (4).
The latter ink isolation layer (9) is provided to prevent the recording paper from being unnecessarily stained by the ink impregnated in the ink retention layer (7) when it comes into close contact with the thermal head (2) and the ink retention layer (7). 7) is provided to isolate the

The recording method will be explained. First, the ink support (2) that has moved from the direction of the arrow in the figure has its ink retaining layer (7)
is filled with ink. When the ink support (4) filled with this ink comes to the recording area on the thermal head (2), the pressure between the thermal head and the platen roller (1) causes the recording paper (8) and the ink support ( 4) and are in close contact with each other.

Then, due to this pressurization, the ink impregnated in the ink retaining layer (7) of the ink support (4) oozes out, and the pores that were not filled with ink are also filled with ink. In other words, due to the spongy nature of the ink retaining layer (7), ink always fills the ink retaining layer (7) on the thermal head (2). An ink support filled with this ink (
4) comes into contact with the heating element (5) of the thermal head (2),
This heating element (5) is heated in accordance with the image signal. The ink filled in the holes enters a bumping state, and bubbles rapidly grow within the ink and fly onto the recording paper (3) to form recording dots. In the figure, αO indicates the ink in that state. During this series of operations, the ink support (4) was in contact with the recording paper (8).
), the ink isolation space layer (8) is the ink retaining layer (7).
Since it is sufficiently thicker, the ink in the holes that are not heated will not ooze out and adhere to the recording paper (3). Furthermore, if an ink anti-affinity agent is applied to these ink isolation space layers (8), ink intrusion can be effectively prevented, and unnecessary ink seepage and stains on the recording paper (8) can be more completely eliminated. becomes possible.

[Other embodiments of the invention]

In the embodiments described above, the ink ejecting method is performed using thermal energy of a heating element provided in a thermal head, but the method is not limited to this, and the method shown in FIG. 2 may also be used. It is as follows. The recording head σD is provided with a recording electrode υ. This recording electrode α
A is connected to a recording electrode drive circuit (not shown) that controls energization according to a recording signal and a power source. The ink support (14) is made up of an ink retaining layer (14) made of an insulating spongy material sandwiched between an insulating ink isolation space layer αO, and has a large number of holes when viewed from above. It consists of an ink retaining layer I that retains the ink when it is supplied by the means, and an ink isolation space layer αO that isolates the ink from the recording paper ae. The recording paper αe is sequentially conveyed by a conductive platen roller α.

This platen roller α is grounded.

Ink fills the holes of the ink support and is conveyed from the left side in the figure. The ink inside this hole is absorbed by the ink retaining layer (I
4) and the ink isolation space layer αe to form a convex meniscus toward the recording paper αe. Pressure is applied to the recording electrode 0 of the recording head (11) and the platen roller α71 from both sides so that the recording paper αQ and the ink support 0 come into close contact with each other. At this time, when a voltage is applied to the recording electrode (2), an electric field is concentrated on the convex meniscus of the ink retaining layer in contact with the recording electrode. The electrostatic force generated by the action of this electric field overcomes the surface tension of the ink, and the ink flies onto the recording paper αΩ.
It is possible to obtain recorded image points.

Further, the structure of the ink support is not limited to that shown in FIG. 2(a). For example, as shown in Figure 2 (bl), an ink retaining layer (a) made of an insulating spongy material is sandwiched between an insulating ink isolation space layer, and a conductive layer is further applied to the surface of the ink isolation space layer (c) on the recording paper @ side. (c) may also be provided.
Numbers used in b) that are the same as in FIG. 2(a) indicate the same parts. By doing so, the electric force acts on ink ejection more effectively. In other words, various modifications can be made without departing from the gist of the present invention.

[Brief explanation of drawings]

FIGS. 1(a) and 1(b) are cross-sectional views showing a recording section of an apparatus according to an embodiment of the present invention, and FIG. 2(a) (bl is a cross-sectional view showing a recording section of another embodiment apparatus according to the present invention. 3 is a diagram showing the recording principle of the present invention, FIG. 4 is a schematic configuration diagram showing a printer made using the recording principle according to the present invention, and FIG.
The figure is a diagram showing the principle of ink transport. l...Platen roller 2...Thermal head 3...Recording paper 4...Ink support 5...Heating resistor element 6...Protective film 7...Ink retaining layer 8.
... Spatial layer for ink isolation 9... Ink isolation layer agent Patent attorney Noriyuki Chika (and one other person) Figure 1 (α) (b) 2nd prisoner Figure 3

Claims (2)

[Claims] (1) An ink support having multiple holes that holds liquid ink, and a recording head that selectively applies heat or an electric field to the ink held in the ink support, and the heat applied by the recording head or ejecting the ink held on the ink support by an electric field, and directing the ejected ink onto a recording medium that is placed so as to sandwich the ink support, face a recording head, and press the ink support in close contact with the ink support; The liquid jet recording device performs recording by adhering the ink to the recording medium, and the ink support has a spongy ink-impregnated layer and an isolation layer for isolating the ink held in the multiple holes from the recording medium. Characteristic liquid jet recording device. (2) The liquid jet recording device according to claim 1, wherein the isolation layer is formed on both sides of the ink-impregnated layer.