JPS6023056A - Recording head - Google Patents

Abstract

PURPOSE:To obtain an inexpensive high speed and high quality full-color printer, by fixing metal wires each having an insulating film to a metal plate provided with holes at equal intervals through said holes to use the same as recording electrodes, and polishing the metal plate. CONSTITUTION:Recording electrodes 201 each having an insulating film are passed through the holes of a metal plate 16 provided with said holes at equal intervals and fixed thereto by solder or a conductive adhesive 17 or the recording electrodes 201 each having the insulating film are arranged on the metal plate 16 and fixed thereto by the conductive adhesive 17. When said recording electrodes are passed through the holes of the metal plate, the single surface of said metal plate is polished. The metal plate for fixing the recording electrodes and the filling material itself are used as return electrodes and crosstalk between the recording electrodes is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printing device, and more specifically, the present invention relates to a printing device, and more specifically, a current is passed through a conductive sheet, heat-melting ink is melted by heat generated by Joule heat, and printing is performed by transferring the ink to a transfer paper. This invention relates to so-called energized heat transfer.

Various attempts have already been made to use heat generated by electricity to melt solid ink and transfer it to recording paper.

The basic concept is shown in Figure 1. The energizing heat generating sheet 1 has a resistance layer 2. Support layer 3. It consists of a heat-melting ink layer 4,
The support layer 3 may also serve as a current-carrying layer. The recording principle is as follows. When a voltage according to a recording pattern is applied to the recording electrode 5 by the signal voltage generator 7, a current flows to the return electrode 6 via the current-carrying layer 2. At this time, if the return path 1L is made to have a sufficiently large contact area between the recording electrode 5 and the current-carrying layer 2, the Joule heat due to the current flow will mostly be generated directly below the recording electrode 5. The generated Joule heat is transferred to the p support 3 by thermal conduction.
The heat-melting ink 4 is melted, and the melted portion of the ink is transferred onto the recording paper 8, thereby making a print.

As described above, recording by energized heat transfer can be performed on plain paper. ■No noise. ■Can record gradations. ■Can record in color. It has advantages such as However, despite having the above-mentioned advantages, the prospects for commercialization are extremely low compared to other printing methods such as the inkjet method and the thermal transfer method using a thermal head. This is due to the following reasons.

The electric heating transfer method that has been proposed in the past basically performs serial printing with a single recording electrode as shown in Figure 1, or has multiple recording electrodes and one return electrode. Either a plurality of recording electrodes were driven one at a time in a time-division manner.

Therefore, these methods were extremely slow and did not lead to widespread commercialization. The reason why it is not possible to increase the speed in this manner is that a plurality of recording electrodes cannot be driven simultaneously according to the above method, and this is based on principle.

This will be briefly explained below.

Now, as shown in FIG. 2, a head with recording electrodes 201 to 215 surrounded by return electrode 101 is pressed against the energized heating sheet to apply a signal voltage.

Now, for example, on the recording electrodes 207, 20.8, 209,
Apply a voltage IVI, disconnect the other recording electrodes,
When the return electrode 101 is set to zero, the equipotential surface in the current-carrying layer becomes as shown in FIG. As shown in the figure, recording electrical contact 207
Since there is no potential gradient between 208 and 208, 208 and 209, the current density decreases compared to when the recording electrode 208 is set to the E loop alone, and in particular, almost no current flows through the middle recording electrode 207. Therefore, printing unevenness and printing omissions occur, making it impossible to perform high-speed printing using conventional methods. It is.

A first object of the present invention is to enable high-speed printing by providing recording electrodes that can simultaneously select a plurality of recording electrodes.

Another object of the present invention is to distribute the current density corresponding to the recording dots, and by changing the intensity, area modulation can be applied to the recording dots to express gradations, thereby achieving low cost and high quality. , it becomes possible to realize a high-speed full-color printer.

The principle of recording by the recording head of the present invention is shown in FIG.

Since the recording electrodes 201 to 203 are surrounded by the return electrode lO1, the lines of electric force from each recording electrode do not interfere with the other recording electrodes. Therefore, unlike the case described above, adjacent recording electrodes can be driven simultaneously and independently.

FIG. 4 shows 1α) the potential distribution in the current-carrying layer when a voltage is applied between the recording electrode 201 and the return electrode 101. Obviously, the potential gradient is considered to be inversely proportional to the distance r from the center of the recording electrode, so the temperature distribution at the X-Y soil is 1b1
As shown in the figure, it becomes an axially symmetrical mountain shape. The solid line and dotted line represent the difference in input energy.

Mltl! If the melting point of the solution ink is T-rI'L,
'rfn or higher g, 4 degrees is transferred to the recording paper. In other words, by changing the input energy, the area of the recording dot will change by l.

Furthermore, as in this system, since the heat generating portion is the current-conducting layer on the side of the passing heat generating sheet, the thermal history is much smaller than that of a thermal head, and good gradation reproducibility can be achieved.

Examples according to the present invention will be shown below.

FIG. 5 shows a recording electrode 201 having an insulating coating 11 used in the present invention. The metal wire 201 has a diameter of 1 μm and is made of tungsten, molybdenum, nickel, copper, or an alloy thereof. When using tungsten or molybdenum, the surface is plated with nickel or the like to enable wiring by soldering.

As shown in FIG. 4, the outer diameter of the insulating film needs to be larger than the desired recording dot diameter because current flows through the gap formed by the insulating layer through the resistive layer. In the case of the present invention, the recording density was set to 5 dots/U, so the outer diameter was set to 30
It was set to 0 μm.

The recording head is fixed with an adhesive by passing an insulated wire shown in FIG. 5 through a metal plate 15 in which two rows of holes 16 are formed in a staggered manner at a pitch of 400 μm as shown in FIG. This 11iy adhesive is preferably one with high heat resistance, and if the insulating film is plated with Ni, it may be identified by solder.

The top surface of this is polished as shown in Figure 7, and the recording head 2 ()
get.

In the recording head described above, the metal plate that fixes the recording electrode 201 and the filling blade itself also serve as the return path and the pole.

As mentioned above, this recording head is capable of recording individual recording '7ji.
Since all the poles are surrounded by return electrodes via insulating layers, there is no crosstalk between recording electrodes, and since the insulating layers are concentric circles, it is possible to record data at high speed. .

As described above, according to the present invention, since a recording head can be realized with a simple tank bottom, an inexpensive, high-speed, high-quality full-color printer can be realized.

[Brief explanation of drawings]

FIG. 1 shows a principle diagram of a conventional energized heat transfer recording system. FIG. 2 shows the potential distribution in the resistance layer when driven by a conventional recording head. FIG. 3 shows a conceptual diagram of a recording head according to the present invention. FIG. 4 Cα1(b) shows the potential distribution and heat distribution of the resistance layer when driven by the recording head according to the present invention. FIG. 5 shows the insulating coated wire (recording electrode) used in the present invention. FIG. 6 shows a metal plate used in the present invention. FIG. 7 shows a staggered recording head according to the present invention. Overelectrical heating sheet - 1 Resistance layer - 2 Support layer - 3 Heat-melting ink - 4 Recording paper - 8 Recording electrode - 201 to 215 Return electrode - 101 Insulating coating (insulating layer) - 11 Metal plate - 15 Recording head - Addition Applicant Suwa Seikosha Co., Ltd. Agent Patent Attorney Mogami Ml Figure 01 (or Figure 2, Figure 31) (1) No. 4. Procedural Amendment (Spontaneous) Patent Application No. 131487 1988 2 Invention Name recording head, 4 Supplement 4-4 Name/Relationship with 11 cases Applicant 4 Agent 5-6-21 Kyobashi 2-chome, Chuo-ku, Tokyo 104 Amendment 1r, J increase in number of inventions Procedural amendment (voluntary) 1. Specification page 6, lines 18 to 7) i4 line [The recording head is shown in Figure 6 and can receive π to 20 cycles]. Gashi7ζ. As shown in FIG.
Fixed with 1 and 17. 4 on the metal board on the 7ζ car
Even if they are arranged at a pitch of 0.00 μm and fixed with conductive adhesive, it will not work. In the case of the present invention, the eighth problem is that two sheets of tiles are placed in a staggered manner to form a recording head with a pitch of 200 μm. ” Hydraulic pressure. Z Specification, page 8, line 8, ``Figure 6 is a metal-like seven embossed version of the present invention.'' Corrected to ``Figure 6 is an embossed version of the recording head according to the present invention.'' . 5 Ming a Cao page 8 line 17 "Metal 4 μm 15 ijC record Heno V'-2 [JJ."

Claims (1)

[Claims] (1) In a printing device for producing a record by passing an electric current through an electrically conductive heating sheet having a resistive layer and a heat-melting ink layer to generate heat and transferring the heat-melting ink onto recording paper. , a recording head passes a wire through a metal plate having a plurality of equally spaced holes and an insulating coating, and fixes this with adhesive,
Furthermore, one side of this metal plate is polished! 4 for collusion
A recording head characterized in that the wire is a recording electrode, and the metal plate and conductive tIL adhesive or solder are a return electrode. ■ The insulating coating is made of a high thermal material such as Teflon or polyimide polymer, and the outer diameter of the insulating coating is larger than or equal to the dot diameter. A recording head according to claim g=1. (2) The recording head according to claim 1, wherein the recording electrodes are arranged in a staggered manner.