JPS6294355A - Recording head - Google Patents

Abstract

PURPOSE:To enhance the durability of a current supply thermal transfer recording head, by using conductive ceramics as the material of a recording electrode. CONSTITUTION:A support 12 is formed of machinable ceramics based on mica and a recording electrode 6 is formed by applying ceramics having conductivity applied thereto to a support according to a CVD method. A recording electrode has three-layered structure consisting of a titanium layer 63, a titanium carbonitride layer 62 and a titanium nitride layer 61 provided from the support side. By this three-layered structure, the close adhesiveness of the recording electrode with the support is enhanced. The conductive ceramics has hardness of about 1,300Hv and extremely hard as compared with a high m.p. metal such as tungsten. The total thickness of the recording electrode is about 10mum. After the conductive ceramics is applied to the entire surface of the support, only the unnecessary part of the conductive ceramics is etched and removed by dry etching to form a desired pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a recording head used in a printing device using an energized thermal transfer recording method.

[Prior Art] As shown in FIGS. 3-A and 3-1, the electrical thermal transfer recording method uses a resistive layer 1 on one side of a base 2 such as a polyethylene film, and a heat-melting ink on the other side. While using the thermal transfer arm 4 on which the layer 3 is formed, a recording head 7 is used in which recording electrodes 6 directly connected to the decoder circuit 5 are arranged at regular intervals. The ink layer 1 is brought into contact with the resistive layer 1 of the film 4, and a voltage is applied between the recording electrode 6 and the return electrode 8 to generate Joule heat in the resistive layer 1, melting the ink layer 3 and forming a predetermined pattern into dots. It is printed by

In addition, compared to the thermal transfer method, the energized heat transfer recording method has features such as better thermal efficiency, less thermal history, high speed printing, and the ability to express high-quality gradations.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional example, the recording electrode is worn out due to mechanical sliding with the resistance layer, discharge during energization, thermal shock, etc. during long-term printing, and the result is This has the problem of poor contact with the resistive layer, resulting in a printing rate of Iil.

In particular, by devising the contact shape between the resistive layer and the recording electrode, creating a gradient in the heat generation distribution on the resistive layer, and changing the input energy, the transfer driver can be improved. - In a gradation printing device that changes the area and enables areal density gradation using a single-layer element, the reproduced density changes slightly depending on the contact shape between the resistive layer and the recording electrode, so slight changes in the shape of the recording electrode This caused a fatal deterioration in image quality. SUMMARY OF THE INVENTION The present invention is intended to solve these problems, and its purpose is to improve the durability of the recording head and provide a high-quality, highly durable head for electrical thermal transfer recording. be.

[Means for Solving the Problems] The recording head of the present invention is characterized in that the recording electrodes are made of conductive ceramics.

[Operation] Originally, it is thought that there are many factors underlying the causes of abrasion of recording electrodes in the electrical thermal transfer recording method. One is the wear of the recording electrode due to purely mechanical sliding with the resistance layer of the thermal transfer film, and the other is the heat generation 1f of the resistance layer when electricity is applied during printing.
The other is wear due to collapse or softening of the recording electrode material due to Ji impact, and the other is wear due to discharge that occurs when printing current is applied.

Therefore, the characteristics required of the recording electrode material are hardness at room temperature, heat resistance (-1
Examples include hardness in a high temperature state of 0°C to 1000°C, discharge resistance, etc.

Ceramics have the above properties that are superior to those of general metals. According to the above configuration, it is possible to realize a head for an electrically conductive thermal transfer recording system with excellent durability.

[Example] Figure 1-A is a structural diagram in an example of the present invention,
FIG. 1-1 is an enlarged view of the tip of the recording section of the recording head according to the present invention. The recording head 7 is composed of a recording section 9, a quick-action IC mounting section 10, and a coupling section 11 that electrically couples the recording section 9 and the quick-motion IC mounting section 0.

In this embodiment, a line head configuration was adopted. The recording section 9 is composed of a recording electrode 6, a support 12 for the recording electrode, and an insulating film 30 on the recording electrode. The support 12 was made of machinable ceramics containing mica as a main component. The recording electrode was made by coating ceramics having conductivity of 1=t,'j-t on the support by CVD method.

The recording electrode has a three-layer structure, and its main components are titanium carbide 63, titanium carbonitride 62, and titanium nitride 61 from the support side. By forming the three-layer structure as shown in "-", the adhesion to the support was improved. The hardness of the conductive ceramic is about 1300 Hv, which is much harder than high melting point metals such as tungsten, and the total thickness of the recording electrode is about 10 μm. After coating the entire surface of the support with conductive ceramics using the above method, dry etching was performed to erode and remove unnecessary portions of the conductive ceramics to form the intended pattern.

P on the recording electrode! The rim film 30 is for preventing conductive dust or peeled pieces of resistive layer components generated during printing from adhering to the recording electrode and causing an electrical short circuit between the conductors. A relatively soft inorganic insulating heat resistant coating material was applied uniformly by dipping. The heat resistance may be such that the resistance layer does not undergo deterioration due to heat generation during printing. In addition, if the material is relatively softer than the recording electrode, even if the insulating layer covers the part of the recording electrode that must be exposed for energization at the tip of the recording head, it will not work as the resistive layer during printing. The sliding of the insulating layer automatically removes the insulating layer, ensuring a good energizing condition at all times, and efficiently removes the peeling components of the resistive layer from the areas that are not involved in energizing and are closest to the heat generating part of the resistive layer. This is because it provides good coverage and protection. In this example, inorganic glass was used.

Of course, the insulating film was manufactured.'' - Appropriate masking was applied to unnecessary areas in advance.

Next, an outline of a printing apparatus using the recording head of the present invention will be described.

FIG. 2 is a diagram showing the structure of an electric thermal transfer printing apparatus using a recording head according to the present invention. A transfer paper 24 is supplied from a transfer paper supply roller 21 and also from a thermal transfer film 4, which is supplied from a supply roller 27, and is pressed and energized onto the platen 23 by the recording head 7. The thermal transfer film 1.4 after printing is wound up by a take-up roller 29.

Thermal transfer film is based on PET with a thickness of 6 μm, and carbon grains are dispersed in the resin as a resistance layer on one side.
One was coated with a thickness of μm, and the other was coated with a pigment dispersed in wax and coated with a thickness of 2 to 3 μl.

Table 1 shows the evaluation results of the durability of the recording head of the present invention and recording heads of other configurations using the printing apparatus described in ``1''. Although titanium carbonitride and titanium nitride were used as the main ingredients, any other conductive ceramics such as silicon nitride, silicon carbide, and tungsten carbide may be used. In addition, in this example, the method of forming the conductive film was C.
VI) method was used, but other P methods such as vapor deposition and sputtering were used.
Furthermore, in this example, after forming a film on the entire surface of the support, a pattern is formed by dry etching. Appropriate masking may be performed at the same time as film formation. It is also possible to use patterning methods other than dry etching, such as electrical discharge machining and machining. Moreover, it goes without saying that the layer structure is not limited to three layers.

Furthermore, regarding the structure of the recording head, a conventional recording head having a return electrode is also sufficiently effective.

[Effects of the Invention] As described above, according to the present invention, by using conductive ceramics for the recording electrode, there is an effect that the durability of the electrically conductive thermal transfer recording head is improved.

[Brief explanation of drawings]

FIGS. 1-A and 1-B are diagrams showing an embodiment of the structure of a recording head using current-carrying heat transfer according to the present invention. FIG. 2 is a diagram schematically showing a printing apparatus using the energized thermal transfer recording head of the present invention. FIGS. 3-A and 3-B are diagrams showing the principle of the electric thermal transfer recording method. 1...Resistance layer 2...Base layer 3...Ink layer 11...Thermal transfer film 5...Drive circuit 6...Recording electrode 7. ... Recording head 30 ... Insulating film

Claims (1)

[Claims] A printing device that obtains a record by applying a voltage to the resistive layer of an electrically conductive thermal transfer film having at least a resistive layer and an ink layer, causing the resistive layer to be energized and generate heat, melting the ink layer, and transferring the ink to a printing medium. A recording head comprising at least a recording electrode for contacting the resistance layer and applying a voltage, and a support member for the recording electrode, the recording electrode being made of conductive ceramics.