JP2757432B2 - Ink recording medium - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink recording medium used for converting an electric signal into thermal energy and transferring an ink image to a transfer material.

2. Description of the Related Art Conventionally, when recording an image corresponding to a predetermined digital image signal on a recording medium, for example, plain paper, a recording method using a thermal transfer recording medium such as an ink donor film is widely known.

Among such recording methods, a current-carrying thermal transfer recording method using a print recording medium provided with a heating layer and a return electrode on a medium-resistance ink support (Japanese Patent Laid-Open No. 56-93585) or a return electrode on the same side as the needle electrode , And a current path to the return electrode is formed in the heat generating layer of the print recording medium to utilize the heat generated in the heat generating layer. The current thermal transfer recording method has a relatively high printing speed and imparts conductivity to the ink. There is an advantage that there is no necessity and the degree of freedom in selecting an ink material is high, and various proposals have been made.
However, in these energized thermal transfer recording methods, since the ink support does not have anisotropic conductivity, there is a spread of dots,
The leakage current is large and the energy efficiency is poor, or the applied current passes through the heating layer twice, causing a lot of energy loss. Also, the sliding contact is performed twice by the needle electrode and the return electrode, so that the contact resistance is reduced. In addition, a large amount of heat loss occurs, and in order to preferentially supply a current to the return electrode, a certain resistance is required for the conductive layer in the print recording medium, and the heat loss in the conductive layer also increases. .

In order to solve this drawback, an ink recording medium having an anisotropic conductive layer provided on one surface of a heating resistor layer, a return electrode layer provided on the other surface, and a conductive layer exposed on both side edges to form a side electrode portion is provided. It has been proposed to perform printing by using a conductive sliding member or a conductive roll in contact with a side end electrode. As an ink recording medium of this type, an isolated electrode pattern layer composed of a large number of minute isolated electrodes, a heating resistor layer that generates heat by input of an electric signal, a conductive layer, an ink release layer, and a heat-meltable ink layer are laminated. Various structures having the following structure have been proposed.

Problems to be Solved by the Invention By the way, in this type of ink recording medium,
Normally, micro-isolated electrodes are made of Ni, C directly on the heating resistor layer.
Metals such as u, Sn, Ta, Ti, Zn, Au, Ag, Fe, Al, Pt, RuO
₂ , conductive ceramics such as SiC, WC, MoSi ₂ , and TiC are deposited by ion plating, sputtering, or vapor deposition, and are patterned by a lithographic method.

When the minute isolated electrode is formed of a metal having a relatively low melting point, such as Cu, there is a disadvantage that abrasion is remarkable due to rubbing with the print recording head. On the other hand, when high-melting point metal or conductive ceramics is used, the point of abrasion due to rubbing with the print recording head is improved, but due to sliding of the print recording head or thermal stress due to heat generation of the thermal resistor. In addition, there has been a problem that the micro-isolated electrode often peels off from the heat-sensitive resistor layer. Therefore, in any case, the life of the ink recording medium is shortened,
Further, there is a disadvantage that a stable recorded image cannot be obtained.

The present invention has been made in view of the above-described problems in the related art.

Therefore, an object of the present invention is to provide an ink recording medium that can be used repeatedly and can perform stable printing and printing, and a printing and recording method using the same.

Another object of the present invention is to enable repetitive printing and recording,
High-speed printing, high-density energy input is possible, high-quality color images can be reproduced, robust images with multiple gradations can be recorded, and energy-efficient printing can be performed. An object of the present invention is to provide an ink recording medium capable of performing print recording at a running cost and a print recording method using the same.

Means for Solving the Problems The ink recording medium of the present invention has a conductive layer, an ink release layer,
And a heat-fusible ink layer were sequentially laminated, and on the other surface of the heating resistor layer, a large number of minute isolated electrodes made of a refractory metal or conductive ceramic were provided as an isolated electrode pattern layer via a metal adhesive layer. It is characterized by the following.

The ink recording medium of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view of the ink recording medium of the present invention, and FIG. 2 is a partially enlarged view of the anisotropic conductive layer of FIG. In the figure, 11 is an isolated electrode pattern layer, 12 is a heating resistor layer, 13 is a conductive layer, 14 is an ink release layer, and 15 is a heat-meltable ink layer. The isolated electrode pattern layer 11 has
1 and a metal adhesive layer 112, and provided on the heating resistor layer 12.

The isolated electrode pattern layer is formed on one surface of a heating resistor layer serving as a support with a large number of minute isolated electrodes made of high melting point metal or conductive ceramics, which are uniformly isolated from each other, via a metal bonding layer.

Materials constituting the metal adhesive layer include Al, Cr, Cu, S
n, Zn, Co, Ag, Pd, Cu-Ni alloy, Co-Ni alloy, Co-Cr
A metal or alloy selected from the group consisting of alloys can be used. The thickness of the metal adhesive layer is preferably formed in the range of 30 to 1000 mm.

A minute isolated electrode is formed on the metal adhesive layer. Examples of the high melting point metal constituting the minute isolated electrode include Ta, T
i, Mo, W, Ru, Re, Rh, Zr, etc. can be used. Examples of conductive ceramics include RuO ₂ , SiC, WC, and MoS.
_{i, TiC, B 4 C,} ZrC, HfC, VC, NbC, W 2 C, TaC, Ta 2 N, Ta
N, TiN, ZrN, NbN, VN, TiB 2, ZrB 2, HfB 2, TaB 2, Mo
_{B, CrB 2, NbB 2,} MoB 2, NbB, Mo 2 B, TaSi 2, WSi 2 , and the like.

The isolated electrode pattern layer, on one surface of the heating resistor layer, the metal or alloy constituting the above-mentioned adhesive metal layer, for example, an ion plating method, a sputtering method, deposited to a predetermined thickness by a vapor deposition method, and then The above-mentioned high melting point metal or conductive ceramics, for example, by ion plating, sputtering, deposition to a predetermined thickness by vapor deposition or the like, and then, for example, by patterning by photolithography and etching Can be formed.

Further, the thickness of the minute isolated electrode is from 500 ° to 30 μm, preferably 10 μm or less.

The pattern area of each minute isolated electrode is not particularly limited as long as each is electrically isolated, and 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 in the print recording head to be pressed. Specifically, pitch 1μm
To 500 μm, preferably a pitch of 10 μm to 120 μm and a diameter of 5 μm to 400 μm in a circular, rectangular or other polygonal shape.

In the ink recording medium of the present invention, the heating resistor layer has a function as a support, and generates Joule heat by current from the isolated electrode pattern layer to melt the ink and transfer it to the transfer material. A resistor layer made of a heat-resistant resin (pyriimide resin, polyimide amide resin, silicone resin, fluororesin, epoxy resin, etc.) in which a conductive substance such as carbon or metal powder is dispersed, ZrO ₂ , Al ₂ O ₃ , SiO ₂ and other high resistance materials and Ti, Al, T
A thin film formed using a conductive material such as a, Cu, Au, or Zr is used. The volume resistivity of the heating resistor layer is 10
^-2 to 10 ² Ωcm, and the film thickness is 1000 to 10
It is preferable to set it in the range of μm. Those in this range have excellent characteristics in film deposition stability, film adhesion, and the like.

The conductive layer diffuses the current flowing into the heating resistor layer,
In the present invention, the electrode is made of metal or conductive ceramic. That is, this conductive layer is made of a metal or a conductive ceramic layer having a Vickers hardness of 1000 or more, having a volume resistivity of 10 ⁻² Ω · cm or less, preferably 10 ⁻⁴ Ω · cm or less. As metal layers, Ni, Al, Cr, Cu, Sn, Zn, Co, Ag, Au, Ta,
Ti, Pd, Cu-Ni alloy, Co-Ni alloy, Co-Cr alloy, etc.,
Examples of conductive ceramics that can be used include metal oxides such as RuO ₂ , metal nitrides such as Ta ₂ N, TaN, TiN, ZrN, NbN, and VN,
_{TiB 2, ZrB 2, HfB 2} , TaB 2, MoB 2, CrB 2, NbB 2, MoB, Nb
Metal borides such as B and Mo ₂ B, B ₄ C, TiC, ZrC, HfC, VC, Nb
Examples include metal carbides such as C, WC, W ₂ C, and TaC, and silicides such as MoSi, TaSi ₂ , and WSi ₂ , which can be used alone or as a mixture. Further, a configuration in which a protective layer of the conductive ceramic is provided on the metal layer may be adopted.

The conductive layer is formed by vapor deposition, sputtering, or other thin film forming methods. The thickness is preferably set in the range of 500 ° to 1 μm.

The ink release layer is a layer adjusted to a critical surface tension so that ink transfer can be performed well even at a low printing energy, and is a thin film having a function of a low surface energy. It has a critical surface tension value lower than the energy. For example, when the transfer material is plain paper, the critical surface tension needs to be 43 dynes / cm or less. Further, when the critical surface tension of the ink release layer is lower than the surface tension of the hot-melt ink layer, it is preferable that a greater effect can be obtained in the transition phenomenon of the hot-melt ink layer. The thickness of the ink release layer itself is 500 mm
It is preferable to set the thickness as thin as possible in the range of 6 to 6 μm from the viewpoint of energy transfer efficiency. As a material constituting the ink release layer, for example, a thermosetting silicone resin,
Fluorine-containing resins can be used.

The heat-meltable ink layer provided on the ink release layer,
A resin obtained by dispersing a known dye or pigment such as carbon black in a thermoplastic resin having a melting point of 140 ° C. or lower is used. The thickness of the hot-melt ink layer is preferably set in the range of 1 to 15 μm.

A method of performing print recording using the ink recording medium of the present invention will be described with reference to FIG.

In FIG. 3, an electric signal is input from the print recording head 2 to the ink recording medium 1 conveyed by the conveying roll 7, and a current flows from the isolated electrode pattern layer via the heating resistor layer and the conductive layer to the return contact roll 5 From ground. The heat-meltable ink melted by the heat generated by the heat-generating resistor layer is transferred to the transfer material 3 on the back pressure roller 4. Reference numeral 6 denotes a backup roll for ensuring contact with the return contact roll. After the printing, the heat-meltable ink is supplied to the ink transfer mark on the ink recording medium, and the colored heat-meltable ink layer is reproduced.

In the ink recording medium of the present invention, the isolated electrode pattern layer provided on the heating resistor layer is composed of a minute isolated electrode made of a high melting point metal or a conductive ceramic, and a metal adhesive layer. Since the isolated electrode is provided on the heating resistor layer via a metal adhesive layer, the minute isolated electrode is firmly adhered to the heating resistor layer. Therefore, even if the print recording head rubs against the surface of the isolated electrode pattern layer, or if the heating resistor layer generates heat and a thermal stress is applied to the isolated electrode pattern layer, the minute isolated electrode separates from the heating resistor layer. Will not be done.

EXAMPLES Next, the print recording medium of the present invention will be described with reference to examples.

Example 1 Cr was deposited on one side of a conductive polyimide film having a surface resistance of 550 Ω / □ and a thickness of 30 μm by a high frequency sputtering deposition method to form a 400 mm thick Cr layer as a metal adhesive layer. And Ta were deposited by a high-frequency sputtering deposition method to form a 4,000-mm-thick Ta layer. Next, a photoresist is formed on the formed Ta layer,
After drying for a minute, a resist film having a thickness of 1.6 μm was formed. The resist film was exposed through a mask having a rectangular pattern of 19 μm square at a pitch of 30 μm on the entire surface, developed, and then heated in an oven at 110 ° C. for 15 minutes in an N ₂ atmosphere to cure the resist film. Next, reactive ion etching was performed to remove Ta and Cr in a portion without a photoresist film. Next, the film was put into an acetone bath, and ultrasonic waves were applied to remove the resist film, thereby completing the formation of a layer made of a conductive pattern of minute isolated electrodes.

Next, on the other surface of the conductive polyimide film, Al was deposited as a return electrode to a thickness of 1200 ° by DC sputtering. A thermosetting silicone resin was applied on the formed return electrode layer, and was heated and cured at 150 ° C. for 1 hour to form an ink release layer having a critical surface tension of 31 dynes / cm and a film thickness of 0.4 μm. In this case, in order to provide a return contact, the film was applied so that the ink stripping layer was not formed on both end belt-shaped portions of the film.

The obtained film was connected so that the isolated electrode pattern layer was on the inside, and an endless belt was produced.

Next, a 6 μm-thick colored heat-meltable ink layer mainly composed of a thermoplastic resin having a melting point of 80 ° C. was provided on the ink release layer to obtain an ink recording medium.

Using this ink recording medium, evaluation was performed as shown in FIG. That is, the return electrode contact part is grounded,
A stylus head having a density of 8 needles / mm was pressed into contact with a pressure of 400 g / cm, and the endless belt-shaped ink recording medium was moved at a speed of 50 mm / sec while applying a current of 20 mA. At this time, the peeling rate of the minute isolated electrode was measured. The results are shown in Table 1.

Comparative Example 1 An ink recording medium was prepared in the same manner as in Example 1 except that the metal adhesive layer made of Cr was not provided, and evaluation was performed in the same manner. Table 1 shows the results.

As is clear from the results in Table 1, in the example of the present invention, it is found that the peeling of the minute isolated electrode is prevented by the effect of the metal adhesive layer below the minute isolated electrode. This is because the adhesion between Ta and the conductive ceramics is low, so that the stylus head slides and peels off due to scratching, and the energizing resistor layer generates heat when the stylus head is energized, causing peeling due to thermal stress. is there.

Example 2 TaN was used as a material for forming a minute isolated electrode, and C
An ink recording medium was prepared and evaluated in the same manner as in Example 1 except that a 2500-nm thick TaN layer was formed on the r layer. The results are shown in Table 2.

Comparative Example 2 Example 2 was repeated except that the metal adhesive layer made of Cr was not formed.
An ink recording medium was prepared in the same manner as described above, and the same evaluation was performed. The results are shown in Table 2.

As is clear from the results shown in Table 2, Example 2
It can be seen that the peeling of the minute isolated electrode is prevented by the effect of the metal adhesive layer.

Effect of the Invention In the ink recording medium of the present invention, since the minute isolated electrode is provided on the heating resistor layer via the metal adhesive layer, the minute isolated electrode is firmly adhered to the heating resistor layer. Therefore, even if the surface of the isolated electrode pattern layer is repeatedly rubbed by the print recording head, or even if the heating resistor layer generates heat and thermal stress is applied to the isolated electrode pattern layer, the minute isolated electrode is separated from the heating resistor layer. It does not peel off.
Therefore, the ink recording medium of the present invention has a longer service life in which repeated use is possible. Therefore, high-speed printing, high-density energy input is possible, a high-quality color image can be reproduced, a robust image with multiple gradations can be recorded, and printing with high energy efficiency can be performed. And printing can be performed at low running cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of the ink recording medium of the present invention, and FIG.
FIG. 3 is an enlarged cross-sectional view of the minute isolated electrode of FIG. 1, and FIG. 3 is an explanatory diagram for explaining a state in which print recording is performed using the ink recording medium of the present invention. 1 ... Ink recording medium, 2 ... Print recording head, 3 ...
Transfer material, 4 ... Back contact roll, 5 ... Return contact roll, 6 ... Backup roll, 7 ... Transport roll, 11
…… isolated electrode pattern layer, 12 …… heating resistor layer, 13 ……
Conductive layer, 14: ink release layer, 15: hot-melt ink layer, 111: minute isolated electrode, 12: metal adhesive layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41M 5/26

Claims (2)

(57) [Claims] A conductive layer, an ink release layer, and a heat-meltable ink layer are sequentially laminated on one surface of a heating resistor layer that generates heat by input of an electric signal, and an isolated electrode is formed on the other surface of the heating resistor layer. An ink recording medium comprising a plurality of minute isolated electrodes made of a high melting point metal or a conductive ceramic as a pattern layer via a metal adhesive layer. 2. The method according to claim 1, wherein the metal adhesive layer comprises Al, Cr, Cu, Sn, Zr, Co, A
An ink recording medium comprising a metal or an alloy selected from the group consisting of g, Pd, Cu-Ni alloy, Co-Ni alloy, and Co-Cr alloy.