JPS63160889A - Electrothermal transfer recording method - Google Patents

Abstract

PURPOSE:To enable high-speed printing and high resolution, by performing energization while moving an electrothermal recording needle and a heat generating plate relative to each other, and thermally transferring a thermal transfer layer by the heat generated by an electrically energized heat generating layer and a conductive layer or by the heat generating layer and a conductive base layer. CONSTITUTION:A heat generating plate comprises an electrically energized heat generating layer comprising a conductive inorganic material having a surface resistance of 10<2>-10<7>OMEGA provided on one side of a plate-shaped body comprising a conductive ceramic and having a surface resistance of 1-10<4>OMEGA and a volume resistivity of 10<-6>-10<3>OMEGA-cm. The heat generating plate is laid on the surface of a conductive layer of a recording material comprising a thermal transfer layer on one side of an insulating base and the conductive layer, which comprises a thin metallic film having a surface resistance of less than 50 OMEGA, on the other side of the base, or is laid on the surface of a conductive base of a recording material comprising a thermal transfer layer provided on one side of the conductive base layer which comprises a metallic foil having a surface resistance of less than 1OMEGA and a thickness of 2-30mum, with the heat generating layer in contact with the surface of the conductive layer or the conductive base layer. Energization is conducted while moving an electrothermal recording needle placed in contact with the other side of the plate-shaped body and the heat generating body relative to each other, and the thermal transfer layer is thermally transferred by the heat generated by the heat generating layer and the conductive layer or by the heat generating layer and the conductive base layer.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an electrically conductive thermal transfer recording method.

(Prior Art) In recent years, information has become extremely abundant, and the need for rapid transmission and recording of that information has increased, and various developments have been made regarding information management systems such as information processing systems, information transmission systems, and information recording systems. A typical example of this is an electrically conductive thermal transfer recording system.

As a recording material used in the above recording system, there is, for example, an energizing recording device described in Japanese Patent Application Laid-open No. 179764/1983. The product described in this publication has a heating resistance layer and a conductive layer formed on one heating sheet and is separated from a heat-melting ink layer, and since the heating sheet can be used repeatedly, it can be used for running without reducing printing speed. It has the advantage of being able to reduce costs.

(Problem to be solved by the invention) However, as a heat generating sheet, polycarbonate with conductive carbon dispersed or metal silicide is used for the heat generating resistance layer, and vapor deposited aluminum or stainless steel film is used for the conductive layer. However, polycarbonate in which conductive carbon is dispersed as a filler has poor durability and is extremely difficult to use repeatedly at a thickness of 0.5 to 2.0 pm. In addition, metal silicide is also 0.5
With a thickness of ~2.0 um, it is extremely easy to break and cannot be used alone. Furthermore, it is not easy to provide a conductive layer on these surfaces.

(Means for Solving the Problems) The present invention has been made to solve the above-mentioned conventional drawbacks, and its gist is that a heat-sensitive transfer layer is laminated on one side of an insulating base material, and the other side is laminated with a heat-sensitive transfer layer. The conductive layer surface of a recording material on which a conductive layer made of a metal thin film with a surface resistance of less than 50 Ω is laminated on the surface of the recording material, or a conductive layer made of a metal foil with a surface resistance of less than 1 Ω and a thickness of 2 to 30 um. A recording material having a heat-sensitive transfer layer laminated on one side of the base layer has a layer made of conductive ceramics and a surface resistance of 1 to 1 on the surface of the conductive base layer.
04 Ω, which is larger than the surface resistance value of the conductive layer, and has a volume resistivity of 10 −6 to 10 3 Ω-cm. Heat-generating plates laminated with electrically conductive heat-generating layers made of conductive inorganic materials having a large The heating plate is energized while moving its relative position, and the heat-sensitive transfer layer is thermally transferred with the heat generated by the energizing heat generating layer and the conductive layer, or the energizing heat generating layer and the conductive base material layer. It is something to do.

(Summary of the Invention) Electrical isotropy as used in the present invention refers to a property in which the flow of an applied current has no directionality.

The heating plate generates heat in the thickness direction directly under the current-carrying recording needle due to the current passed from the current-carrying recording needle that is in contact with the heat-generating plate. It is a stack of electrically conductive heat generating layers made of inorganic materials.

The plate-like body has the role of maintaining the self-supporting properties of the heating plate and allowing the current to flow only in the thickness direction directly below the current recording needle. When the volume resistance of this plate-like material becomes small, too much current flows through it and it becomes difficult to generate heat.On the other hand, when the volume resistance becomes large, it becomes difficult for current to flow and it becomes difficult to generate heat, so the volume resistance is 10-6.
~103Ω-equipment. In addition, when the surface resistance of this plate-like material decreases, the amount of current passed directly under the current-carrying recording needle decreases, making it difficult to generate heat. Ru.

In the present invention, conductive ceramics are used as the plate-like body, and examples of the conductive ceramics include molybdenum silicide (MoSiz), titanium carbide (TiC), tungsten carbide (WC), and zirconium boride (Zrll).
z), silicides, carbides, borides, nitrides of transition metals such as titanium nitride (TiN), silicon carbide (SiC), lanthanum chromate, etc. are suitable. Among these, the volume resistivity of ZrBz, TiC, TiN, etc. is 10-6 to 10-bΩ-. In addition, in order to adjust the volume resistance value and improve the physical properties such as strength of the conductive ceramics, non-conductive ceramics may be mixed as necessary, and examples of the non-conductive ceramics include beryllium oxide (Bed), oxide Magnesium (MgO
), oxides such as aluminum oxide (AlzO,), aluminum nitride (AIN), boron nitride (O
N), nitrides such as silicon nitride (Si3N4), and carbides such as boron carbide (84C) are suitable.

In this way, a plate-shaped body made of conductive ceramics or a mixture of conductive ceramics and non-conductive ceramics is electrically isotropic with no directionality in the flow of current.

Among the above-mentioned plate-shaped bodies, those using conductive ceramics are used with a thickness in the range of approximately 10-tsoum.

However, since conductive ceramics are brittle,
If it is thinner than m, it is particularly prone to breakage, and if it is more than 150 um, the applied current will be excessively diffused, resulting in a significant decrease in the resolution of the recorded image. Therefore, a more preferable thickness is 50 to 120 um.

The thickness of the current heating layer is preferably 2 to 50 um, and the conductive inorganic material constituting the current heating layer has a surface resistance of 1
02 to 107 Ω and a surface resistance higher than that of the conductive layer described later, for example, ruthenium oxide glass,
Tin oxide (Snug) and other low conductivity ceramics are suitable.

The conductive layer and the conductive base material layer of the present invention serve as a counter electrode for the current-carrying recording needle, and also conduct heat generated by the heating plate to the heat-sensitive transfer layer, and the conductive layer is not destroyed by the current flow. Although it is not necessary, it is preferable that heat is generated by being destroyed, since sufficient heat can be given to the insulating base material.

If the surface resistance of the conductive layer and the conductive base layer becomes large, they will no longer function as a counter electrode, so the surface resistance of the conductive layer is less than 50Ω, and the surface resistance of the conductive base layer is 1.
made smaller than Ω. Further, the ratio of the surface resistance of the current heating layer and the plate-like body is determined to be in the range of 10-105.

If the thickness of the conductive layer is thinner than 0.05 um, the surface resistance will increase and it will not function sufficiently as a counter electrode.
If it is thicker than this, the conductivity of heat will be poor, and it will be difficult to be damaged by electricity, causing disadvantages such as the heat from the heat generating plate will be diffused and it will take time for heat transfer, so the thickness should be 0.05 to 10 um.
It is done. Further, the thickness of the conductive base material layer is preferably 2 to 30 um for the same reason as the above-mentioned conductive layer and from the viewpoint of durability as a base material.

As the conductive base material layer, for example, a metal foil such as aluminum, stainless steel, copper, or brass is suitable, and as the conductive layer, a thin film obtained by vacuum-depositing aluminum is suitable. Further, as the conductive layer, conductive ceramics laminated on one surface of the heating plate by thermal spraying or the like can also be used.

In the present invention, a heating plate is superimposed on the conductive layer side or the conductive base layer side of the recording material via the current-carrying heat-generating layer, and a current-carrying recording needle is placed on the surface of the heat-generating plate opposite to the current-carrying heat-generating layer. Thermal recording is performed by contacting the recording needle and energizing the recording needle. In other words, when electricity is applied to the current-carrying recording needle, point heat generation occurs directly below the part of the heating plate that the current-carrying recording needle contacts, and this heat is transmitted through the conductive layer and the insulating base material, or through the conductive base material layer. The ink in the heat-sensitive transfer layer is dissolved and transferred onto the surface of a recording medium such as plain paper that is superimposed on the heat-sensitive transfer layer. Note that the current flowing through the conductive layer or the conductive base material layer is returned to the power source through another return electrode that is in contact with the heat generating plate.

At this time, in the case of an electrically sensitive layer made of a metal thin film, when the metal thin film is broken by electric current, it generates heat and further supplements the amount of heat generated by the heat generating plate, which is preferable because thermal transfer is easy and a high density image can be obtained. In this way, although the four-electroconductor layer may be destroyed by discharge, it is a thin metal film, so although it is scattered by discharge destruction, soot and bad odor are not generated, and a small amount of it adheres to the heating plate, so it can be used as appropriate. If removed, there will be no practical problem at all.

On the other hand, with a conductive base material layer made of metal foil, no discharge damage occurs due to energization, and the heat generated by the heat generating plate is transmitted through the metal foil to the heat-sensitive transfer layer. The required amount of heat can be supplied sufficiently, and images with high density can also be obtained.

According to the present invention, by applying electricity while moving the relative positions of the energizing recording needle and the heat generating plate during thermal transfer recording, heat is not stored in the heat generating plate, and recording can be performed more efficiently.

Furthermore, since the heat generating plate has high conductivity in the thickness direction, even if the thickness of the heat generating plate is increased, image density and sharpness are not impaired. Furthermore, the heating plate has excellent abrasion resistance, is durable, and can be used semi-permanently, making it economical. It also simplifies the structure of the printer because it does not require a long heating sheet as in the past. .

(Example) Next, an example of the present invention will be described. Hereafter simply "department"
"parts by weight" means "parts by weight".

[Example 1] A plate-shaped body having a thickness of 40 um was obtained by polishing a ceramic plate obtained by sintering silicon carbide (SiC), which is a conductive ceramic, using a hot press method.

The plate had a volume resistivity of 50XlO-''Ω-0 and a surface resistance of 50Ω.Next, a ruthenium oxide-glass based resistance paste was screen printed on one side of the plate and baked. A heat generating plate was obtained by forming an energizing heat generating layer with a film thickness of 20 um and a surface resistance of 5 Ω.

K) Resin (manufactured by Honshu Kagaku Co., Ltd., trade name 15tln80)
100 parts metal-containing dye (manufactured by Hodogaya Chemical Co., Ltd., trade name: Suhiunburafuku BNH)
25 Part Beeswax
15 parts carnauba wax
15 parts ethyl acetate
50 parts toluene
25 parts Next, the compound having the above composition was dissolved and dispersed, and applied to the other side of the polyester film on which a conductive layer consisting of an aluminum vapor-deposited layer with a surface resistance of 0.8 Ω was formed, and dried to give a thick A heat-sensitive transfer layer with a thickness of 3 um was formed to obtain a heat-sensitive transfer recording material with a thickness of 9 um.

The resulting heat-sensitive transfer recording material was cut into a width of 7 m, and the energized heat-generating layer surface of the heat-generating plate was superimposed on the conductive layer of the heat-sensitive transfer recording material. A high-quality paper is brought into contact with the underside of the heat-sensitive transfer layer, an energized recording needle is brought into contact with the heating plate, and a DC voltage of 20 V is applied to the energized recording needle.
Scanning line density 161/m, recording speed 1, 2 m/s
When electricity was recorded under EC conditions, there was no soot or carbon black scattering or bad odor, there were no through holes in the heating plate or polyester film, and a clear black color was printed on the high-quality paper without cutting during recording. Image obtained.

The density of the obtained image is 1.35, and the resolution is 16.
It was j2/N. Similar results were obtained after repeated use of the heat generating plate over a distance of 20 m.

[Example 2] One side of the plate obtained in Example 1 was coated with tin oxide (S
forming a current-carrying heating layer with a film thickness of lOum,
A heating plate was obtained.

Next, a heat-sensitive transfer recording material similar to that in Example 1 was obtained, this heat-sensitive transfer recording material was cut into widths of 7 mm, and the current-carrying heat-generating layer surface of the heat-generating plate was superimposed on the conductive layer of the heat-sensitive transfer recording material. The paper was supplied to the same mimeograph paper making machine as in Example 1, high-quality paper was brought into contact with the bottom of the heat-sensitive transfer layer, and an energized recording needle was brought into contact with the heating plate, and energized recording was performed under the same conditions as in Example 1. There was no scattering or bad odor of the carbon blank, no through-holes were formed in the heating plate or polyester film, and clear black images were obtained on the high-quality paper without being cut during recording. The density of the obtained image is 1.35, and the resolution is 1
64! /am. Similar results were obtained after using the heating plate 20 times.

[Example 3] The following material was used in place of the thermal transfer recording material of Example 1. That is, a compound having the following composition was dissolved and dispersed on one side of a conductive base layer made of aluminum foil with a surface resistance of 0.1 Ω and a thickness of 108 m, and the mixture was applied and dried to form a heat-sensitive transfer layer with a thickness of 3 um. A thermal transfer recording material was obtained.

H resin (manufactured by Honshu Kagaku Co., Ltd., trade name nan 80) 1
00 parts metal-containing dye (manufactured by Hodogaya Chemical Co., Ltd., trade name: SUHION PLAFUK BNH)
25 parts ethyl acetate
50 parts toluene
25 parts carnauba wax
15 parts beeswax 1
5 parts The surface of the energized heat generating layer of the heat generating plate obtained in Example 1 was superimposed on the surface of the conductive base material layer made of aluminum foil, and energization recording was performed under the same conditions as in Example 1. As a result, soot and carbon black were removed. There was no scattering or bad odor, no through holes were formed in the heat generating plate, and a clear black image was obtained on the high-quality paper. The density of the obtained image was 1830, and the resolution was 151/mm. Similar results were obtained after using the heating plate 20 times.

(Effects of the Invention) Since the present invention has the above-described structure, there is no need to replace the heating plate even if it is repeatedly used for a long period of time, and running costs can be significantly reduced.

Furthermore, since the heating plate has electrical anisotropy, it can be made thicker and has excellent durability. Furthermore, since a reinforcing member for reinforcing the heat generating plate is not required, the structure of the printer printing unit can be simplified, and the manufacturing cost of the entire printer printing unit can be reduced. Furthermore, since the heat generating position is concentrated at one point and brought closer to the recording material, the amount of energy applied is reduced and thermal diffusion is suppressed, thereby improving resolution. In addition, it is possible to eliminate background smudges and print tails on the recording medium due to heat accumulation, so that the high speed printing and high resolution that are the characteristics of the electrically conductive thermal transfer system can be effectively achieved.

Patent applicant Sekisui Chemical Co., Ltd. Representative Hiro 1) Kaoru

Claims (1)

[Scope of Claims] 1) The conductivity of a recording material in which a heat-sensitive transfer layer is laminated on one side of an insulating base material and a conductive layer made of a metal thin film having a surface resistance of less than 50Ω is laminated on the other side. The layer surface or surface resistance is less than 1Ω and the thickness is 2 to 30u.
A conductive substrate layer made of conductive ceramics having a surface resistance of 1 to 10^4 Ω and having a surface resistance of 1 to 10^4 Ω of a recording material in which a heat-sensitive transfer layer is laminated on one surface of a conductive base layer made of a metal foil of is larger than the surface resistance value of the sexual layer and has a volume resistivity of 10^-^6 to 10^3 Ω-cm
The surface resistance on one side of the plate-shaped body is 10^2 to 10^7Ω.
A heat-generating plate laminated with a current-carrying heat-generating layer made of a conductive inorganic material having a surface resistance larger than that of the plate-like body is superimposed via the current-carrying heat-generating layer, and a current-carrying recording needle is placed on the other side of the plate-like body. The electricity is applied while moving the relative position of the current-carrying recording needle and the heat-generating plate, and the heat generated by the current-carrying heat-generating layer and the conductive layer, or the current-carrying heat-generating layer and the conductive base layer causes the temperature to rise. An electrically conductive thermal transfer recording method characterized by thermally transferring a thermal transfer layer. 2) The ratio of the surface resistance of the current heating layer and the plate-shaped body is 10 to 10^
5. The electrically conductive thermal transfer recording method according to claim 1.