JPS5824460A - Electric conduction transfer recording method - Google Patents

Abstract

PURPOSE:To provide video recording at high resolving power, high density and high quality using small energy, by a method wherein diameter of electrodes and distance between the recording electrode and the return electrode satisfy a specific condition, when an electric conduction is performed in a conductive ink sheet and ink is melted and transferred for printing. CONSTITUTION:An ink sheet 1 is overlaid on a recording paper 2. A needle- shaped recording electrode 3 and a return electrode 4 spaced by a prescribed distance from the recording electrode 3 and having large contact area are contacted with upper surface of the ink sheet 1. Connection is effected between both electrodes 3, 4 corresponding to video signal, and an ink layer adjacent to the recording electrode 3 is melted by means of Joule heat and ink is transferred to the recording paper 2 for recording. If thickness of the ink sheet is l, values are specified to satisfy the formulasI-III.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording method in which an ink sheet is melted by Joule heat caused by electricity and transferred to a recording medium.

Previously, the inventor contacted the ink sheet as a medium,
Ink sheet) A needle-shaped recording electrode and a return electrode are brought into contact, an image signal voltage is applied between them, and the ink sheet near the arrangement electrode is melted by heat generated by electrical current, forming a recording medium. We have proposed an electrical transfer recording method that transfers images.

Ink sheets used in this electrical transfer recording method are generally disclosed in JP-A-49-38629 and JP-A-53-724.
6 and Japanese Patent Application Laid-Open No. 56-8276, which consist of a conductive ink layer and an anisotropically conductive base layer, are known.

However, the ink sheet shown in the specification of JP-A-49-38629 has an anisotropic conductive base layer in which ferromagnetic metal powders dispersed in a binder resin are oriented in a constant magnetic field. Since it is made of a large area, it is not possible to produce a uniform image over a large area. Therefore, the electric transfer le sickle method using this ink sheet has the disadvantage that when a large area ink sheet is used, the arranged image is not uniform.

Furthermore, the ink sheet shown in the specification of JP-A-53-7246 has an anisotropically conductive base layer in which metal powder is dispersed in a binder resin, but it is difficult to disperse the metal powder, and the metal powder is difficult to disperse. Since agglomerated areas occur, the current transfer recording method using this ink sheet does not rely on faithful energization to the recording electrodes, resulting in a decrease in resolution.

Furthermore, there is an ink sheet shown in the specification of JP-A No. 56-8276, in which the anisotropically conductive paste layer is made of silicone rubber and conductive material such as metal or carbon arranged in a columnar manner in the thickness direction. The maximum resolution of the current transfer recording method using an ink sheet is about 4 lines/■.

Furthermore, the above-described current transfer recording method is expensive because its ink sheet uses special materials and manufacturing methods.

An object of the present invention is to enable recording of images with high resolution, high density, and high quality without using an ink sheet made of special materials and manufacturing methods, and with sufficient recording energy. Another object of the present invention is to provide a current transfer recording method.

In the present invention, a conductive multi-ink sheet consisting of a single layer that can be thermally melted is stacked on a recording medium, a needle-shaped recording electrode and a return electrode are brought into contact with the ink sheet, and an image signal voltage is applied between these electrodes. In the current transfer recording method, in which the ink sheet is energized by applying a current to melt the ink sheet using Joule heat and is transferred to the recording medium, the thickness of the ink sheet is determined. If the diameter of the recording electrode is d, the distance between the recording electrode and the return electrode is K, and pi is K, then l(
It is characterized by satisfying the following conditions.

The present invention will be explained in detail below with reference to the drawings.

The ink sheet used in the current transfer recording method of the present invention has a single heat-meltable layer and is electrically conductive, and is formed by uniformly dispersing a conductive coloring material in a binder resin. The nine resins suitable for the above binder resins include:
Examples include polycarbonate, polyvinyl butyral resin, acrylic resin, and vinyl chloride resin, and it is desirable that the softening point or melting point thereof is 100 to 250C. Suitable materials for the conductive colorant include various raw materials such as carbon black and dyes.

As shown in FIG. 1, an ink sheet (IK) 1 configured as described above is stacked on a recording medium 2 such as paper, and an ink sheet (IK) needle-shaped recording electrode 3 and a return electrode 4 arranged at a predetermined interval from the ink sheet IK are arranged. The contact area of the return electrode 4 with the ink sheet IK is made much larger than the contact area of the recording electrode 3 with the ink sheet 1, and an image signal voltage applying device 5 is applied between the recording electrode 3 and the return electrode 4. When an image signal voltage is applied, the ink sheet near the recording electrode 3)1
A part of it is melted by the Joule heat generated by electricity and transferred to the recording medium 2.

When an image signal voltage is applied between the recording electrode 3 and the return electrode 4, a current flows in the ink sheet 1, and the contact area of the return electrode 4 with the ink sheet IK is
Since the area of contact with the ink sheet 1 is much larger, the current density near the recording electrode 3 is much larger than the current density near the return electrode 4, and the total current density flowing between the recording electrode 3 and the return electrode 4 is much larger than the current density near the return electrode 4. Since the current is the same, the Joule heat near the recording electrode 3 becomes larger than the Joule heat near the return electrode 4, which is necessary to melt the ink sheet 1. )1
A part of it is melted by Joule heat and transferred to the recording medium 2.

The thickness of the ink sheet 1 is j, the diameter of the recording electrode 3 is d, the distance between the recording electrode 3 and the return electrode 4 is D,
In addition, it is necessary to satisfy the following conditions, where pi is π.

Since the ink sheet 1 has the same volume resistivity in the thickness direction and in the planar direction, it is necessary to satisfy /<' t and l<D. In this way, the resistance R1 in the thickness direction of the ink sheet 1 can be made smaller than the resistance R1 in the planar direction, so that current can be mainly applied in the thickness direction of the ink sheet 1. Inksy) 10 How to maintain strength! ≧5 μ sea bream is required, and the recording energy increases in proportion to 7! Must be ≦30 voices. The practical range of resolution is 8 to 16 dots/
Since it is W, it is necessary that 50μ clear≦d≦150μ clear.

In the case of 2d)D, the ink sheet 10 portion between the recording electrode 3 and the return electrode 4 will be melted and transferred to the recording medium 2Ilc, so it is necessary to satisfy the condition 2d≦D. As D becomes larger, energy consumed in the current-carrying path other than the arrangement portion increases, so a preferable condition for d and D is 5d≦D≦80d.

πdD Furthermore, the reason why it is necessary to satisfy the condition that 50≦-[ and -≦5X10' is explained below.

If the volume resistivity of the ink sheet 1 is pv, then the resistance R1 in the thickness direction and the resistance R in the planar direction of the ink '/-) 1
, is expressed by the following formula R@'Q jl y
(up to), preferably 10-1 to 10'' Ωl.

The above (1) t (to calculate the ratio of R2 and R1 from Equation 21) is expressed by the following equation.

However, the value of! Although it depends on
Since it is a μ trout, the variable that can greatly change the value of KE is D.

Therefore, when we investigated the changes in recording energy and dot magnification when D was mainly varied in the range of Kzv 10 to 10'', we found that the recording energy was approximately as shown in song!IA in Figure 2. It increased as K K x increased, and the dot expansion rate decreased as K Kz increased, as shown by curve B in Figure 3.

Practically speaking, it is desirable that the recording energy is 20 mJ/dot or less, and the dot magnification is -20- to +1.
Since it is desirable that it be 00-, it should be 50≦! ≦5×1
It is necessary to satisfy the condition 0.

Note that a plurality of recording electrodes 3 may be arranged in a row, held by an insulating electrode holder, and an image signal voltage may be applied between the recording electrodes 3 and the return electrode 4. , a plurality of recording electrodes 3 may be arranged in a plurality of rows, and each row of recording electrodes 3 may be located between recording electrodes 3 of other rows.

Example In the above-described current transfer recording method, polycarbonate 8
0~90wt- and conductive carbon black 10~201
i1%, and the volume resistivity ρV is 0.03 to 0.
38 (using an ink sheeter that is jtxx, d-13
0 μ sea bream, D = 1
When a pulsed image signal voltage of m1ec was applied, dots were obtained which had the same round shape as the recording electrode 3 and a diameter of approximately 15μ, and the density of the dots was 1. θ〜
1.2 and the quality of the dots was high. Further, it was confirmed that the maximum resolution was about 16 dots/lIK.

The current transfer recording method of the present invention does not require the use of an ink sheet made of special materials and manufacturing methods, and has high resolution and
It is possible to record high-density and high-quality images, and
The recording energy is also sufficiently low.

[Brief explanation of the drawing]

FIG. 1 shows the structure of an apparatus for implementing the present invention, and FIGS. 1, 2, and 3 are diagrams for explaining the present invention in detail. DESCRIPTION OF SYMBOLS 1... Ink sheet, 2... Recording medium, 3... Recording electrode, 4... Return path electrode, 5... Image health signal voltage application device

Claims (1)

[Claims] A conductive ink sheet consisting of a single layer that can be thermally melted is placed on a recording medium, and a needle-shaped recording electrode is brought into contact with a nine-return electrode arranged at a predetermined distance from the ink sheet. In the energization transfer placement method in which an image signal voltage is applied between the electrodes and the ink sheet is energized, the ink sheet is melted by George's heat and transferred to the placement medium, the thickness of the ink sheet is determined. , d is the diameter of the auxiliary electrode, d is the distance between the recording sickle electrode and the return electrode, and
If pi is π and 9, then j(d, 2d≦4)
1111, an electrical transfer recording method.