JPH01178460A - Image recording apparatus - Google Patents

Abstract

PURPOSE:To enable the quick and sure control of ink supply onto the surface of an ink transfer means and to obtain an image of high picture quality, by enabling the conduction of electricity through the intermediary of fluid ink transferred by the ink transfer means, between the ink transfer means and a coating means. CONSTITUTION:An ink transfer roll 1 is so disposed as to be rotatable in the direction of an arrow A while transferring fluid ink 2, on the left side of an ink retaining means 3 for retaining the ink 2. Under the ink retaining means 3, a coating roll 4 applying the ink 3 in a prescribed layer thickness for coating on the surface of the ink transfer roll 1 is disposed. The surface of the coating roll 1 is formed of a conductive material such as stainless steel, and this enables the desired conduction of electricity through the fluid ink 2 to the ink transfer roll 1. By this electrification, a sticking force of the fluid ink 2 is varied selectively, and this facilitates quick and sure implementation of the application of the fluid ink 2 onto the ink transfer means 1 and the fitting and removal thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION 1. Summary of the Invention The present invention relates to an image recording apparatus capable of recording on a recording medium at low cost using fluid ink.

! Today, a variety of information processing recording methods have been developed that can record on plain paper, such as impact printers, electrophotography, laser beam printers, and thermal transfer printers. There is.

Among these, thermal transfer type recording devices are widely used because they have low noise and can be miniaturized. This recording method uses an ink ribbon made by coating hot-melt ink on a base sheet, heats the ink ribbon in an image pattern with a recording head, and transfers the molten ink to recording paper. This has advantages such as low noise, relatively small device size, and low device cost.

However, in the conventional thermal transfer method described above, when manufacturing an ink ribbon, it is necessary to apply heat-melting ink onto a heat-resistant base sheet in a complicated process, and this ink ribbon cannot be used for one recording. There were problems such as high running costs because the devices had to be disposed of only after being used.

As a means to solve the above-mentioned problems, the present applicant has previously developed a method in which a fluid ink is transferred in the form of a film using an ink transfer means, and a predetermined energy is selectively applied to this ink to make it stick in an image pattern. proposed a recording apparatus that forms a colored ink image and transfers this ink image onto a recording medium (Japanese Patent Application No. 175191/1982).

This recording device does not require the use of an ink ribbon as in conventional thermal transfer methods, and by transferring only the ink that forms an ink image onto the recording medium and repeatedly using the ink that does not form an ink image, Although this enables low-cost recording, it is desired that such recording apparatuses also be able to support higher speeds and more colors.

11 11 An object of the present invention is to improve the recording apparatus to enable quick and reliable control of ink supply to the surface of the ink transport means, prevent image deletion, etc., and provide a high-quality image. The purpose is to provide a recording device.

Another object of the present invention is to provide an image recording device that is more suitable for high-quality images while maintaining high image quality.

As a result of intensive research, the present inventors have found that it is possible to utilize the difference in adhesive strength between the anode side and the cathode side based on energization when forming an ink layer on the ink transport means using a rotatable coating means. It has been found that the ink layer can be quickly and reliably attached to and detached from the ink transport means, and is extremely effective in achieving the above object.

The image recording device of the present invention is based on the above knowledge,
More specifically, an image recording apparatus capable of transferring fluid ink to a recording medium in response to selective application of energy, comprising: an ink transport means for transporting the fluid ink; and an ink transport means for transporting the fluid ink. an energy applying means for selectively applying energy to the transferred ink; a transfer means for transferring the ink, the transfer characteristics of which have changed in accordance with the selective application of the energy, to a recording medium; a rotatable coating means disposed facing the ink transport means upstream of the energy application means in a direction in which ink is transported by the ink transport means, and for supplying ink to the ink transport means at a constant thickness; death,
Further, the present invention is characterized in that electricity can be applied between the ink transfer means and the coating means via the fluid ink transferred by the ink transfer means.

In the image recording device of the present invention having the above configuration,
Based on the energization between the ink transport means and the coating means, it is possible to selectively impart tackiness to either the ink transport means side or the ink coating means side of the ink layer between them. It becomes possible to quickly and reliably control the attachment and detachment of the ink coating layer to and from the ink transport means, thereby facilitating high-speed image recording.

Furthermore, according to the image recording apparatus of the present invention, even when two or more fluid inks of different colors are used, they can be quickly and reliably attached to and detached from the respective ink transport means.
By cutting these inks, it becomes easy to handle multicolor printing.

Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary. In the following description, 1% represents the quantitative ratio.
and "part r" are based on weight unless otherwise specified.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Refer to FIG. 1, which is a schematic side sectional view as seen in the thickness direction of a recording medium, showing an embodiment of the image recording apparatus of the present invention, and FIG. 2, which is a partial schematic perspective view of the apparatus. Meanwhile, the basic configuration of the recording apparatus will be explained.

Referring to FIG. 1, an ink transport roll 1, which is an ink transport means whose surface is made of stainless steel or the like, is placed to the left of an ink holding means 3 holding fluid ink 2 (the ink 2 of the ink holding means 3 is stored). The ink 2 is placed on the ink reservoir 3a side).
is arranged so as to be rotatable in the direction of arrow A while being transferred.

Below the ink holding means 3 (on the upstream side in the direction of transport of the ink 2), a coating roll 4, which is a coating means for coating the surface of the ink transport roll 1 with the ink 3 in a constant thickness, is installed on the ink transport roll 1. It is arranged at a constant distance from the outer peripheral surface. The surface of this coating roll 1 is made of a conductive material such as stainless steel,
The ink transport roll 1 is constructed so that desired current can be passed through the fluid ink 2 between the ink transfer rolls 1 and 1.

At the ink transfer position, a cylindrical shape whose surface is made of stainless steel or the like is placed above the ink transfer roll 1 in the drawing (the surface of the ink carrying roll 1 or the ink carrying surface side), facing the roll 1 with a certain gap. An intermediate transfer roll 5, which is an intermediate transfer medium and is rotatable in the direction of arrow B, is disposed.

This intermediate transfer roll S is arranged so that its surface can come into contact with the layer 2a of fluid ink 2 formed on the surface of the ink transport roll 1.

In the present invention, it is also possible to omit this intermediate transfer roll 5 and configure the ink layer 2a to directly contact the recording medium 6 made of coated paper or the like.

On the other hand, at the ink image transfer position, a recording medium 6 made of plain paper or the like and transported in the direction of arrow C is placed in contact with the surface (ink image forming surface) of the intermediate transfer roll 5. be done. Further, a platen roll 7, which is a transfer means, is disposed so as to be able to sandwich the recording medium 6 with the intermediate transfer roll 5, and whose surface is made of silicone rubber or the like and which rotates in the direction of the arrow. Ru.

On the surface side of the ink transfer roll 1 on the upstream side of the ink transfer position where the ink transfer roll 1 and the intermediate transfer roll 5 face each other, with a certain gap from this surface, there is provided a means for applying energy according to an image signal. A recording electrode 8 is arranged. The tip of this recording electrode 8 (one end where the electrode element is formed)
is arranged so as to be able to contact the ink layer 2a on the surface of the ink transport roll 1.

In the image recording apparatus of the present invention having the basic configuration as described above, an intermediate transfer roll is placed on the intermediate transfer roll 5 on the downstream side of the ink image transfer position where the intermediate transfer roll 5 and the platen roll 7 face each other. A cleaning means 9 having a blade 98 made of urethane rubber or the like is disposed as necessary so as to be able to come into contact with the surface of the cleaning means 5 . According to the image recording apparatus of the present invention, as will be described later, the fluid ink 2 Fl 2 a is formed in a uniform thickness on the ink transport means 1 by the coating means 4, and the Fl 2 a is transported by the ink transport means 1. By applying energy corresponding to the image signal to the ink 2, an ink image with changed transfer characteristics is formed, and the ink image is transferred to the recording medium 6. Furthermore, ink 23 that was not transferred to the intermediate transfer roll
As the ink transfer roller 1 rotates, the ink is re-accommodated in the ink reservoir 3a and used again, so that high-quality image recording can be performed at low cost.

The configuration of the image recording device of the present invention is as described above,
The operation of such a device system will be explained next.

In the following, a preferred embodiment of the present invention, that is, a case where a portion of the fluid ink 2 to which energy has been applied is selectively transferred to the intermediate transfer roll 5 will be described.

Referring to FIG. 1, the fluid ink 2 in the ink reservoir 3a is a fluid ink that has fluidity but has tackiness and can be made tackified by applying electrical energy. Use. The tack here refers to selective tackiness; when ink comes into contact with an object such as an intermediate transfer medium, a portion of the ink breaks off from the entire ink (that is, selectively separates) and adheres to the object. Say what you do.

In other words, it does not matter whether the entire ink is sticky or not, such ink 2 has a gel state in a broad sense in which the solvent is retained by a crosslinked structure chamber, for example, the patent application previously filed by the present applicant. Gansho 61-175191
The inks described in No. 62-131586 are preferred.

As the ink transfer roll 1 rotates in the direction of the arrow, the fluid ink 2 is carried in the direction of the arrow while being supported on the surface of the roll 1.

The fluid ink 2 thus transferred is applied with a patterned voltage according to the image signal from the recording electrode 8 at an energy application position where the ink contacts the recording electrode 8 . A current based on the voltage flows from the recording electrode 8 to the ink transfer roll 1 via the fluid ink 2, so that the fluid ink 2 is selected based on a change in the crosslinking structure due to an electrochemical reaction in the ink 2, for example. It imparts a certain level of tackiness.

The fluid ink 2 imparted with selective tackiness is further transferred in the direction of the arrow to form a layer 2a made of the ink 2.
The intermediate transfer roll 5 comes into contact with the ink transfer position, and the above-mentioned selective tackiness 1. Based on this, at least a portion of the ink 2 constituting the ink layer 2a formed on the ink carrying roll 1 is transferred onto the intermediate transfer roll 5 rotated in the direction of arrow B, thereby forming the ink pattern 21.

The ink pattern 21 formed on the intermediate transfer roll 5 is also transferred as the roll rotates in the direction of arrow B, and at the ink image transfer position, it is applied to the recording material 6 under pressure from the platen roll. to form a transferred recorded image 22. Recording medium 6 on which this transferred recorded image 22 is recorded
is moved in the direction of arrow C (first
(left side of the figure).

On the other hand, at the ink transfer position, the fluid ink 2 that has not been transferred to the intermediate transfer medium roll 5 is further transferred in the direction of arrow A, and is transferred to the intermediate transfer roll 5 by the action of gravity etc. based on its non-adhesive property. The ink is separated and returned to the ink reservoir 3a, where it can be used again based on its fluidity.

The operation of the image recording device of the present invention is as described above.
In the present invention, the fluid ink 2 is configured to be energized between the ink transport roll 1 and the coating roll 4.

This energization is carried out by selecting the anode side or the cathode side so that adhesiveness is selectively imparted to either the ink transfer roll 1 side surface of the ink layer 2a or the coating roll 4 side surface.

More specifically, when coating the ink transport roll 1 is started (for example, when the image recording apparatus is started to be used), it is preferable to apply electricity so that the ink layer 2a on the ink transport roll side becomes sticky.

Although it is possible to coat the ink 2 on the ink transfer roll 1 even when no electricity is applied in this way, in the case where no electricity is applied in this way, as shown in the examples below, it is possible to coat the ink 2 on the ink transfer roll 1. It takes a relatively long time to stably obtain the ink layer 2a of uniform thickness.

On the other hand, when it is desired to interrupt or terminate the coating of the ink 2 onto the ink transfer roll 1, it is preferable to apply electricity so that the coating roll 4 side of the ink layer 2a becomes sticky. In this case, for example, by removing the ink layer 2a on the ink transport roll 1 corresponding to a relatively large blank (non-image area) of the recording material 6, the rotational speed of the intermediate transfer roll 5 and furthermore the recording material It becomes possible to "fast-forward" the transport speed of the material 6 regardless of the rotational speed of the ink transport roll 1, and the overall recording speed can be improved. Note that when the ink j12a is not removed, the intermediate transfer roll 5 is usually set to be approximately the same as the ink transfer roll 1 in order to suppress non-selective full-layer transfer of the ink layer 2a to the intermediate transfer roll 5. It is preferable to rotate at a constant speed (or rather at a low speed).

The electricity supply between the ink transfer roll 1 and the coating roll 4 as described above is normally carried out for a certain period of time when coating the ink layer 2a on the ink transfer roll 1 is started or when coating is interrupted (or finished). This current application time varies depending on the composition of the ink 2, the thickness of the ink layer 2a to be formed, etc., but is generally 10 seconds or less, and moreover O, S~
It is preferable that the time is about 3 seconds from the viewpoint of striking a balance between preventing unnecessary changes in the physical properties of the ink 2 and ensuring that the ink is attached and detached.

Furthermore, if electricity is applied to the ink transfer roller side so as to make it sticky, a hard, skin-like layer is formed on the surface of the ink layer 2a. This reduces unevenness on the surface of the ink layer, prevents the ink from twitching or trailing when the head contacts the head, and provides a better image (during recording).

As described above, by supplying electricity between the ink transport means 1 and the coating means 4 via the fluid ink 2 transported by the ink transport means 1, the fluid ink 2 is transferred to the ink transport means 1 or coating. By selectively changing the adhesion force to the means 4, coating and attachment/detachment (peeling off of the ink layer) of the fluid ink 2 onto the ink transport means 1 can be made faster and more reliable.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Ink formulation> Part by weight After cooling to ℃ (room temperature), add borax (Na2 B407 '1
0H20) 14 parts by weight, and an appropriate amount of IN-NaOH (
(approximately 15 parts) to prepare a fluid gel ink.

This ink was applied to the apparatus shown in FIG. 1 to conduct an image formation test.

Referring to FIG. 1, the coating roll 4 is a 40'-IIIMφ cylindrical roll made of stainless steel 304 (surface polished with a grinder), and made of stainless steel 304 whose surface has been blasted (Rz=100 μm). Ink transfer roll 1 consisting of a cylindrical roll (40mmφ)
The ink transfer roll 1 and the intermediate transfer roll 5, which is made of stainless steel and has a cylindrical roll of 40 mm+φ (surface polished with a grinder), face each other at an interval of d2=1 mm at the ink transfer position. = facing each other with an interval of 1 mm.

Ink reservoir 3a of the apparatus shown in FIG. 1 having the above-described configuration
Then, the gel ink 2 suitable for the present invention obtained as described above was added, and an image was printed.

The ink transfer roll 1 is in the A direction, and the coating roll 4 is
were rotated in the F direction at a circumferential speed of 20 am/sec. Immediately after putting the gel ink 2 into the ink reservoir 3a, the ink transfer roll 1 is used as an anode and the coating roll 4 is used as a cathode via the ink 2, and a voltage of 15V, 1
Electricity was applied for sec.

As a result, the ink 2 becomes partially sticky on the anode side, increases its adhesion to the ink transfer roll 1, and is deposited on the surface of the ink transfer roll 1 within a few seconds after the ink transfer roll 1 starts rotating. Uniform coating was achieved, and the surface of the ink layer 2a was smooth. Although it was possible to coat ink onto the ink transfer roll 1 even without such energization, in this case it took several tens of seconds for uniform coating to occur. However, depending on the purpose of the ink coating, this may be inconvenient. In this way, the above-described energization between the ink transfer roll 1 and the coating roll 4 had a remarkable effect on the attachment and detachment of the ink layer 2a.

The intermediate transfer roll 5 is moved in the direction indicated by the arrow B in contact with the layer 2a of ink 2 formed on the ink transport roll 1 as described above.
direction at a rotation speed of about 20 mm/sec. At this time, at the energy application position, the ink transfer roll 1
If electrical energy is not supplied to the ink layer 2a from the recording electrodes 8 which are opposed to each other with a gap of 0°8cm, the ink 2 is actually transferred onto the intermediate transfer roll 5. I didn't.

On the other hand, the recording electrode 8 having a plurality of electrode elements (the area of the electrode element made of logicum plated copper exposed from the insulating film is 100 μta x 10'0 μm) is used as an anode, the ink transport roll 1 is used as a cathode, and the ink layer 2a is When a pulse of 15 V and 5 m sec was applied through the ink, the ink 2 was selectively transferred onto the intermediate transfer roll S, and an ink pattern 21 was formed.

Furthermore, at the ink image transfer position, a platen rotating at the same speed as the intermediate transfer roll 5 in the direction of the arrow C is attached to the intermediate transfer roll 5 via a recording material 6 made of plain paper that is fed in the direction of the arrow C. When rolls (a 16 mm diameter iron cylindrical roll with a 2 inch thick silicone rubber layer provided) were placed facing each other and a slight pressure was applied from this platen roll 7,
A black dot image (
A print) 22 was obtained on the recording material 6.

Further, the ink remaining after transfer, which was not used for image formation on the recording material 6 and remained on the intermediate transfer roll 5, was cleaned by the cleaning means 9.

Next, electricity was applied at 15 V for 2 to 3 seconds through the gel ink layer 2a, using the coating roll 4 as an anode and the ink feed roller 1 as a cathode. As a result, the ink 2 became partially sticky on the anode side, that is, the coating roll 4 side, and became hard on the cathode side, that is, the ink transfer roll 1 side. The ink layer 2a on the ink transport roll 1 was wrapped around the coating roll 4 by a portion of the sticky ink. As a result, the intermediate transfer roll 5 does not come into contact with the ink layer 2a, and the rotation speed of the roll 5 can be easily increased.
Rapid forwarding of the recording material 6 is now possible. This method of attaching and detaching the ink layer 2a on the ink transport roll 1 was more effective when used in a recording apparatus that uses inks of two or more colors.

After the above-mentioned fast forwarding was completed, in order to obtain an image again, the ink transport roll 1 was used as an anode and the coating roll 4 was used as a cathode, and electricity was applied at 15V for 1 sec in the same manner as described above. Coating is quickly done again, and image 2 is formed on the recording material 6 in the same manner as described above.
2 was obtained.

5 JJL Yuku Ink Prescription> Part by Weight After heating the ingredients of the above Prescription A at 70 to 80°C for 10 minutes, add a predetermined amount of the above silica and stirring.
After cooling to 0.degree. C., 50 drops of 10% borax aqueous solution were added, and the mixture was thoroughly stirred to prepare a gel-like fluid ink.

The ink 2 thus obtained was applied to the apparatus shown in FIG. 1 in the same manner as in Example 1, and the ink layer for image formation and ink transport roll 1 was carried out in the same manner as in Example 1, except that the following recording conditions were adopted. When 2a was subjected to i-desorption, good results similar to those in Example 1 were obtained.

<Recording conditions> Peripheral speed of ink transfer roll 1: 40 mm/sec Peripheral speed of coating roll 4: 25 mm/sec Current conduction (during image formation) IOV, 2m5ec Pulse conduction (during coating) IOV, 1 s
ec

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view in the thickness direction of a recording medium of a recording apparatus according to an embodiment of the present invention, and FIG. 2 is a partial schematic perspective view of the apparatus. 1... Ink transport roll 2... Fluid ink 3... Ink holding means 4... Coating roll 5... Intermediate transfer roll 6... Recording material 7... Platen roll 8...・Representative diagram of recording electrodes: Fig. 1 Fig. 1

Claims (1)

[Scope of Claims] An image recording apparatus capable of transferring fluid ink to a recording medium in response to selective application of energy, comprising: an ink transport means for transporting the fluid ink; and an ink transport means for transporting the fluid ink. an energy application means for selectively applying energy to the ink transferred by the means; a transfer means for transferring the ink, the transfer characteristics of which have changed in response to the selective application of the energy, to a recording medium; , rotatable coating means disposed facing the ink transfer means upstream of the energy application means in the direction in which the ink is transferred by the ink transfer means, and for supplying ink at a constant thickness to the ink transfer means; has
An image recording apparatus characterized in that electricity can be supplied between the ink transport means and the coating means via fluid ink transported by the ink transport means.