JPH062418B2 - Print recording medium - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink medium for print recording which converts an electric signal into heat energy and transfers the ink to plain paper by the heat energy to form an image.

2. Description of the Related Art Conventionally, as a printing method for forming an image by converting an electric signal into heat energy and melting the ink with the heat energy to transfer it to a paper, a print recording medium provided with an electrically heated ink is provided on a support. An electric signal corresponding to the image is applied from the support side by the needle electrode to directly energize the ink through the support, and the heat generated at that time melts the ink and transfers it to paper, so-called energization transfer There is a way.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in such a print recording medium, a high resistance resin film and a resin body in which metal powder is dispersed are used as a support,
Since the support and the energizing needle electrode are in direct sliding contact with each other, the conductive loss on the contact surface is large, and the electrical anisotropy in the print recording medium is insufficient, causing leakage, resulting in an extremely large energy loss. It was difficult to properly control the dot precision.

As a similar energization transfer method, a print recording medium composed of a heating element layer, a return electrode layer, and a hot-melt ink layer, which generate heat when an electric signal corresponding to an image is input from an electrode in pressure contact, is used. In some cases, electric energy is also supplied by rubbing against the electrodes, a current path is formed in the heating element layer, and the heat in the heating element layer causes the ink in the hot-melt ink layer to melt and transfer to the paper. Although proposed, even in this method, there is a large conduction loss at the contact surface between the needle electrode and the heating element layer, or since the heating element layer does not have anisotropic conductivity, there is a large leak current that does not contribute to heat generation and there is an extremely high energy loss. It was difficult to properly control the accuracy of the printed dots.

The present invention has been made for the purpose of improving the drawbacks of the above-mentioned conventional energization transfer method, and an object of the present invention is to perform printing with less conductive loss between a needle electrode for applying an image electric signal and a print recording medium. Providing a recording medium.

Another object of the present invention is to provide a conductive print recording system,
In addition to providing a print recording medium with high print dot accuracy,
An object of the present invention is to provide a print recording medium having high energy efficiency in the conductive print recording system.

Another object of the present invention is to provide a print recording medium having good durability.

And an object of the present invention is a print recording medium having a heating element layer which generates heat by inputting an electric signal corresponding to an image from an electrode in pressure contact, a conductive layer, and a hot-melt ink layer which is melted by heat generation of the heating element layer, This is achieved by arranging a large number of electrically isolated microelectrodes on at least the surface of the print recording medium on which the electrodes are in pressure contact.

Further, since many micro electrodes provided on the electrode pressure contact surface side of the print recording medium are present between the print needle electrode and the print recording medium, the contact resistance between the print needle electrode and the print recording medium is lowered. It is provided for the purpose of reducing the heat generation loss in the current path in the recording medium and at the same time suppressing the heat generation in areas other than the heat generating layer.

On the other hand, as a print recording medium in which a large number of electrically isolated microelectrodes are provided on at least the surface on which the electrodes of the present invention are in pressure contact, heat is basically generated by inputting an electrical signal corresponding to an image. Any heating element of the electrical heating type having a heating element layer, a conductive layer, and a heat-melting ink layer that melts due to heat generation of the heating element layer can be used. In addition to a print recording medium that is formed by sequentially stacking ink layers and arranging a number of electrically isolated microelectrodes on the side of the heating element layer, anisotropic heating on the heating element layer side (perpendicular to the surface of the recording element) Direction) may be provided.

Further, as the print recording medium of the present invention, one having an ink peeling layer at the interface between the conductive layer and the hot melt ink layer can be used. Such an ink peeling layer may be made of a wax-based material that melts when heated, or a heat that peels the melted ink due to the difference in surface energy that does not melt when heated like a low surface energy resin layer. It may be a molten layer.

Means and Actions for Solving the Problems The print recording medium of the present invention will be described in detail with reference to FIGS. 1 to 3. First, a large number of print recording media, which are the features of the present invention, on the electrode pressure contact surface side. Microelectrode 1 provided
The volume resistivity of each layer is the layer 2 on which the microelectrode 1 is provided.
It is necessary to have a value lower than the volume resistivity value of, but it is preferable to have a value of 1/100 or less. The area of each microelectrode 1 is not particularly limited as long as they are electrically isolated, and the size of the microelectrode 1 can be arbitrarily determined in terms of image dot transfer position accuracy and energy efficiency. It is preferable that the area is equal to or smaller than the area of one pixel electrode of the image signal applying electrode 6 to be in pressure contact, specifically 4/5 or less, and more preferably 1/5 or less. For example, from a circle having a square of 5 μm or a radius of 5 μm to a microelectrode 1 having a circle of 400 μm square or a radius of 400 μm, 10 μm to 500
It is good to arrange them at a pitch of μm. If the area of the pixel electrode is much smaller than the area of the pixel electrode, the current flux of the layer heat layer 2 may be coarse and spread, the energy efficiency may be deteriorated, and the image quality may be deteriorated.

Each microelectrode 1 needs to be electrically isolated. Specifically, the surface other than the microelectrode 1 is preferably made of a member having a volume resistance value 100 times or more that of the microelectrode 1. Only the microelectrode 1 is provided, and the microelectrodes are separated from each other by a space. Besides being electrically isolated, an insulating member may be provided between the electrodes 1 to electrically isolate the electrodes. Specific materials for forming the microelectrodes 1 include metals such as Au, Cu, Cr, Al, Ni, Fe, Pt, Ta, Ah, and Zn, RuO ₂ , SiC, WC, MoSi ₂ , TiC, etc. Any conductive material such as conductive ceramics, polyacetylene, and a polymer material obtained by dispersing a conductive material may be used, and specifically, the volume specific resistance value is 10 ³ Ωcm or less, preferably 10 ⁻² Ω.
cm or less is good. The thickness of the electrode 1 is preferably 40 μm or less, more preferably 1 μm or less. It is preferable to provide a large number of these microelectrodes 1 uniformly on one side surface of the print recording medium, but they may be provided in part, and the size of each microelectrode 1 may be the same or different. The shape of these microelectrodes 1 is arbitrary. As a method of forming the microelectrode 1, any method such as a vacuum vapor deposition method, a sputtering method, a photolithography etching method, a plasma CVD method, a printing method can be used.

In the print recording medium of the present invention, the volume specific resistance value of the heating element layer 2 provided with the microelectrodes 1 is from 10 ⁻³ Ωcm to
Values in the range between 10 ⁴ Ωcm are preferred, 10
A value in the range of ⁻¹ to 10 ² Ωcm is preferable because a particularly good printing quality can be obtained.

The heating element layer 2 preferably has a heat resistance of 200 ° C. or higher, preferably 300 ° C. or higher. Specifically, for example, a resin such as a polyimide resin, a polydiphenyl ether resin, a polyamideimide resin, a polyesterimide resin, or the like. In addition to those in which conductive powder such as carbon powder or conductive ceramic powder is dispersed, those in which a composite metal and a composite ceramic are physically deposited are listed. The thickness of the heating layer is 1000Å-10
0μ is preferable, more preferably 1μm to 50μ
Those of m are good in terms of strength and heat generation efficiency. An anisotropic conductive layer 3 may be provided between the heating element layer 2 and the microelectrode 1. This conductive layer 3 has a role as a return electrode for an applied signal, and such a return electrode layer may be made of a conductive material, such as Al, Cr, Cu, Ni, Au, Ag, Pt. , F
Metals such as e, alloys, carbon, conductive organic substances, conductive ceramics, etc. are used. The thickness of the return electrode layer 3 is 200
Å to 10 μm is good, preferably 800 Å to 1 μm
Is good. The hot-melt ink layer 5 may be formed by dispersing a known dye or pigment such as carbon black in a wax binder, or may be formed by dispersing a dye or pigment in a resin binder. The resin may be crystalline or amorphous as long as it is a thermoplastic resin, but it is preferably a polymer substance having a melting point of 200 ° C. or lower and a glass transition point of 120 ° C. or lower. .

The ink peeling layer 4 is provided between the hot melt ink layer 5 and the conductive layer 3.
Is preferably provided. The ink peeling layer 4 may be made of a wax-based material that melts when heated, and does not melt when heated like a low surface energy resin layer and peels only the melted ink due to the difference in surface energy. The above layer may be used, and the latter is preferable from the viewpoint of reproducing and using the print recording medium because only the ink layer needs to be reproduced.

The critical surface tension value of the ink release layer 4 such as the latter is preferably lower than the critical surface tension (γ ₀ ) value of the transfer material surface (paper, film, etc.) to which the ink is to be transferred. Paper and OHP film are approximately 42 to 45
Since it has a value of about dyn / cm, it is preferable that the ink peeling layer 4 has a value of 35 dyn / cm or less.

Examples of the ink release layer 4 having a low surface energy property include a hard coat film or a plasma-polymerized film of fluorine resin, silicone resin or the like, and silicone resin is particularly preferable because it can easily form a uniform thin layer.

The thickness of the ink release layer 4 is 10 μm or less, especially 1 μm
The following is preferable.

Next, a print recording method using the print recording medium of the present invention will be described with reference to FIG. 3. In the ink medium having the above-described structure, the printing electrode 6 is arranged so that the isolated conductive pattern 1 side is in contact with the printing electrode 6. And the elastic press contact member 8 between the transfer machine 7
In addition, as shown in FIG. 3, it is used for printing and recording, and a current path is provided in the heating layer 2 between the printing electrode 6 and the return electrode layer 4 by the image signal input applied to the printing electrode 6. By forming and melting the heat-melted ink layer 5 by the heat energy generated at that time, and transferring the melted ink 9 to the transfer machine 7 pressed against the heat-melted ink layer 5, the melted ink 9 is transferred onto the transfer machine 7. An image corresponding to the image input signal can be recorded.

The image input signal to the printing electrode 6 is more efficiently driven when it is applied to the return electrode layer 3 in synchronization with the signal frequency, but a bias voltage is directly applied to the return electrode layer 3 or is grounded. Alternatively, a simple and inexpensive driving method may be adopted.

The energization path of the applied image electric signal may be transferred to the conductive layer 3 by any method, but as shown in FIG. 4, for example, the electrode a may be provided on the same side as the signal application needle electrode b to form a closed circuit. Good. In this case, the pressing area of the electrode a to the print recording medium needs to be sufficiently larger than that of the signal application needle electrode b. Alternatively, a closed circuit may be formed by providing an electrode taken out from the conductive layer 3 in the non-printing portion of the print recording medium and sliding this electrode with another electrode.

Next, examples and comparative examples will be described.

Example 1 Cu was deposited to a thickness of 2000 Å on both sides of a 25 μm thick sheet of polyimide resin in which conductive carbon was mixed and dispersed by 45 wt% using an electron beam vacuum deposition apparatus, and then a thermosetting silicone resin was applied to the upper surface of 0.8 A thickness of μm was applied by dipping to provide an ink release layer having a critical surface tension of 31 dyn / cm. Next, an OFPR photo resist solution manufactured by Tokyo Ohka Kogyo Co., Ltd. was applied to the lower Cu film surface at a rotation of 3000 rpm using a spinner, dried at 80 ° C. for 6 minutes, and then a polka dot pattern of 20 μmφ30 μm pitch was baked to develop for OFPR. 3 sides development with the agent, 3 sides washing with water, dipping in a 20wt% iron chloride solution for 2 minutes, etching the Cu thin film outside the polka dot pattern, washing with water and drying, and the isolated conductor pattern on the entire lower surface of the conductive polyimide film. Provided.

2wt% of 6μm thickness and melting point 105 ℃ on the tongue of ink release layer
A heat-fusible ink layer of a thermoplastic resin material in which the azo pigment was dispersed was provided, and this was used as an ink medium.

Using a stylus line print head with a density of 8 lines / mm of 100 μm square, a pulse width of 400 μs and a 12 V signal are input to the stylus, and electricity is applied from the stylus to the surface of the isolated conductor pattern of the ink medium. established the paper pressed with a press pressure of 600 g / cm ^2, at the signal input to the plain paper
A dot transfer image of 120 μmφ was recorded.

Next, when a signal was input with a signal pulse width of 80 μs and 12 V using the above printing device, a 170 μmφ dot transfer image was created on plain paper.

Comparative Example 1 Using the ink medium of Example 1 having no isolated conductor pattern on the surface and using the same printer, a pulse width of 400 μs,
A 12V signal was input, but there was no transfer image.

When a signal was applied under the signal application conditions of a pulse width of 800 μs and 50 V, a 90 μφ dot image was transferred. However, the concave trace due to the current flow is 130μ in the stylus contact area of the ink medium.
mφ remained.

Example 2 Conductive Polycarbonate (Hoechstone Macro Hole)
Sheet 30μm thick with double-sided Cr by electron beam vacuum deposition
A 5000 Å thick conductive film was created. Next, a thermosetting silicone resin was applied on the upper surface, dried and cured to form a 1.0 μm thick film.
Then, an ink release layer having a critical surface tension of 29 dyn / cm on the surface was provided. Next, a photoresist is applied to the lower Cr surface using a spinner, and after drying, a grid-like isolated conductor pattern having a pitch of 20 μm and 15 μm square is baked. After development and hardening, etching is performed with dilute hydrochloric acid, followed by washing and drying to form a Cr layer of the grid-like isolated conductor pattern. Was set up.

Melting point 95 containing 3 wt% color pigment on the ink release layer
A 8 μm thick heat fusible ink layer was provided. This was used as the ink medium.

Next, a stylus electrode having a diameter of 45 μm is used to press a line printing head of 16 lines / mm pitch against the surface of the isolated conductor pattern of the ink medium, plain paper is pressed against the ink layer side, and a pressure roller with a rubber hardness of 45 is pressed on the back surface. The sliver head was pressed at 800 g / cm ² , and a signal pulse of 15 V was applied with a pulse width of 500 μs to print a dot image of 70 μmφ on the paper surface.

Curing of the Invention The print recording medium of the present invention has the following effects because a large number of microelectrodes are provided in the portions that are in pressure contact with the signal applying electrodes.

(1) Since the contact resistance between the print recording medium and the signal application electrode can be reduced, heat loss in the electrode contact portion and the heating element layer is reduced, and printing energy efficiency is good.

(2) Unnecessary heating in the print recording medium and the electrode contact portion is eliminated, and the current-carrying portion of the heating element uniformly generates heat, so that the print recording medium is hardly thermally damaged.

(3) The heat generation amount can be controlled easily by the signal input electricity amount, the print dot control can be easily performed, and the transfer response of the ink material is excellent. A highly accurate dot image can be obtained.

(4) Since there is no unnecessary heating in the print recording medium, a large input signal can be applied with a short pulse, and printing speed can be increased.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a sectional view of an ink medium, FIG. 2 is a plan view of the same, FIG. 3 is an operation explanatory view, and FIG. 4 is a conventional explanatory view. 1 is an isolated conductor pattern, 2 is a heating layer, 3 is a return electrode layer,
4 is an ink peeling layer, 5 is a hot melt ink layer, and 6 is a printing electrode.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication point 8907-2C B41J 3/20 117 A (72) Inventor Naho Naho 2274 Hongo, Ebina City, Kanagawa Prefecture Fuji Zero Tux Co., Ltd. Ebina Business Site (72) Inventor Kiyoshi Horie 2274 Hongo, Ebina City, Kanagawa Prefecture Fuji Zero Tux Co., Ltd. Ebina Business Site (56) References JP 62-244697 (JP, A) JP 58-90976 (JP, A)

Claims (2)

[Claims] 1. A print recording medium having a heating element layer that generates heat when an electric signal corresponding to an image is input from an electrode that is in pressure contact, a conductive layer, and a hot-melt ink layer that melts due to heat generation of the heating element layer. A plurality of fine electrodes electrically isolated from each other are provided on at least the surface of the surface on which the electrodes are in pressure contact with each other. 2. The print recording medium comprises a heating element layer, a conductive layer, a heat-melting ink peeling layer, and a heat-melting ink layer, which are sequentially laminated from the electrode pressure contact surface side. Print recording medium.