JPH0343259A - Manufacture of thermal head and manufacture of glaze substrate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a thermal head used in a thermal recording device.

Conventional thermal heads are classified into (1) planar type and (2) end face type depending on the position in which the heating resistor is formed. Fig. 3 shows an example of the structure of a conventional planar thermal head, and Fig. 4 shows an example of its manufacturing process. Fig. 5 shows an example of the structure of an end-face type thermal head, and Fig. 6 shows its manufacturing process. FIG. 3 shows an example of each.

In FIG. 5, 1 is an alumina substrate, 2 is a heat storage layer, 3 is a common electrode, 4 is an individual electrode, 5 is a heating resistor, 6 is a protective layer,
7 is the thickness t of the heat storage layer. In order to increase heat generation efficiency in the thermal head, heat storage N2 must be provided on the substrate. This M thermal layer 2 is generally a glass layer such as glazed glass.

As shown in FIG. 4, in the conventional flat thermal hesode, a paste containing a glass component is screen printed 10L on an alumina substrate 1, and this is fired 11 to form heat storage N2. After forming 13, the heating resistor 5 is formed 16 and the protection layer N6 is formed 1B. In addition, as shown in FIG. 6, in the end face type thermal head, after forming ii1 electrode 3 on alumina substrate 1, screen printing 10 of a paste containing a glass component and baking 11 are repeated several times to form heat storage M2. Next, after forming 12 the individual electrodes 4 and forming 11Ji6 of the electrodes, the end faces of the laminated substrates are cut 15.Next, the heat generating resistor 5 is formed 16, and then the heat generating resistor 5
(individual can) 17.

Problems to be Solved by the Invention However, the conventional thermal head manufacturing method including the above steps has the following problems.

■ It is difficult to adjust the thickness of the heat storage layer, and the edges of the print tend to be particularly thick.

(2) When the heat storage layer becomes thick, several tens of micrometers or more, as in the end-face type, the printing and firing steps must be repeated several times, making it difficult to obtain a more uniform thickness. Furthermore, in FIG. 5, the length of the heating resistor is defined by the thickness t of the heat storage layer formed by printing, so that the length of the heating resistor varies.

Means for Solving the Problems In order to solve the above problems, the present invention includes a step of bonding an insulating green sheet to a pre-sintered substrate by heat pressing as a means for forming a heat storage layer etc. which is an insulating layer of a thermal head. The present invention provides a method for manufacturing a thermal head, and a method for manufacturing a glaze substrate, including a step of firing the thermal head.

Function: According to the present invention, the heat storage layer is formed of a green sheet having a uniform thickness. The green sheet and the sintered substrate can be bonded together by using a thermoplastic resin as a binder for the green sheet and hot pressing the green sheet with the sintered substrate. Since the green sheet is supported by the substrate, thick undulations do not occur after sintering. Therefore, by changing the thickness of the green sheet, the thickness of the heat storage layer and the protective layer can be easily adjusted, and the thickness of the heat storage layer and the protective layer can be adjusted evenly to the edges. heat storage layer.

A protective layer can be obtained. In addition, especially in the case of edge-type thermal heads where the heat storage layer has a thickness of several tens of micrometers or more, it can be formed in one heat pressing process and one baking process, which is faster than when using screen printing. The number of man-hours can be reduced, and the length of the heating resistor can be easily defined.

Furthermore, the tlA edge material composition and the electrode material composition are -i
The number of manufacturing steps can be reduced by hot-pressing green sheets patterned one by one or in multiple layers onto a sintered substrate.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

In the example, a 96% alumina substrate is used.

Embodiment 1 FIG. 1 shows an example of the configuration of a planar thermal head according to the present invention.

For example, the green sheet contains 10 parts of the thermoplastic resin polybutyl methacrylate (PBMA) and 3 parts of the plasticizer DBP to 10 parts of the lead borosilicate glass frit by weight. ? MEK, which is an 8-part agent, was blended to a concentration of 40, mixed and dispersed using a ball mill, and then shaped into a sheet bottom using a doctor blade method.

Manufacturing begins with a green sheet at 70'C, 20kg/cj
It is hot pressed onto the alumina substrate 1 for 1 min. After that, it was baked in the air at 900'C for 30 minutes, and the heat storage 11
2, a glazed aluminum substrate l on which a glaze layer is formed is manufactured. Next, a gold thin film is formed using gold resinate, and then patterned by photoetching to form individual electrodes 4 and common electrodes 3. After printing a resistor paste using a screen printing method, it is fired to form a heating resistor 5. Next, a resistor paste is printed using a screen printing method.
A protective layer 6 is formed by printing a material and firing it.

In this thermal head made of birch with a heat storage layer formed of a green sheet, the thickness of the heat storage layer 2, which affects printing quality, is uniform, so that good printing can be obtained with little unevenness.

Embodiment 2 FIG. 2 shows an example of the configuration of an end face type thermal head according to the present invention.

Examples of green sheets include Affi203 (55% by weight), SiO2 (24% by weight), B20B (2.4% by weight), Na20 (1.2% by weight), and 20 (0.8% by weight).
(% by weight), Cab (3,2% by weight), Mg0 (1,2% by weight).

The weight ratio of polybutyl methacrylate (PBMA), which is a thermoplastic resin, is 10. DBP (3,
? MEK, which is an S agent, is blended to a concentration of 40, mixed and dispersed in a ball mill, and then formed into a sheet by a doctor blade method.

The manufacturing process begins by printing a thick gold paste on an aluminum substrate 1, baking it, patterning it by photo-etching, and forming a common electrode 3.
Hot pressing is performed on the alumina substrate 1 on which the common electrode 3 is formed under the conditions of 'C, 20'u/cj 1 min. Thereafter, the heat storage layer 2 is formed by firing in air at 900°C.
Next, individual electrodes 4 are formed on the heat storage layer in the same manner as the common electrode 3 is formed. The thickness of the electrode was approximately 4 μm. Next, the end surfaces of the heat storage N2 and the substrate 1 were polished obliquely so that a plurality of ends of each electrode layer were exposed. If necessary, a preventive layer may be further formed on the individual electrodes using a green sheet to prevent chipping during polishing. Next, tantalum nitride, which is a resistor material, is deposited on the polished surface using a sputtering method. , forming the heating resistor 5.

Next, the heating resistors 5 are separated into individual parts using a laser. 8 is a laser cut groove.

In this end-type thermal head, in which the heat storage layer 2 is formed on the keyaki by adhering a green sheet, the thickness t of the heat storage layer, which defines the length of the heating resistor, is uniform, so the variation in individual resistance values is reduced by 5. % or less, the thickness of the heat storage layer can be easily controlled, and it can be formed in one firing.

Example 3 In the case of manufacturing an edge-type thermal head having the same structure as Example 2, a pattern of CuO paste consisting of CuO powder, glass frit, and vehicle was printed on both sides of the green sheet shown in Example 2, and this lamination was performed. Heat press the green sheet onto the alumina substrate. In this case, the green sheet may have multiple layers.The 0th order, the laminated substrates are debindered in the air at 800°C, and the 500°
After reducing CuO in a reducing atmosphere of about C, 900°
C1 Calcinate in a non-oxidizing atmosphere. Thereby, the common electrode 3, the heat storage layer 2, and the individual electrodes 4 can be formed at the same time.

After this, the end face is polished in the same manner as in Example 2 to form the heating resistor 5.

By forming a thermal head using a green sheet that is a laminate with an electrode material in this way, the number of manufacturing steps can be reduced and the thermal head can be easily lidded. Naturally, this method can also be applied to manufacturing flat thermal heads.

Example 4 For example, in the green sheet, the weight ratio of polybutyl methacrylate (PBMA), which is a thermoplastic resin, to 100 parts of lead borosilicate glass flint is 10 parts, and DBP, which is a plasticizer, is 3 parts. MEK, which is a solvent, is mixed and dispersed in a ball mill to form a sheet using a doctor blade method.

This green sheet is heated at 70°C, 20kg/c+j1m
The sample is hot pressed onto alumina-based FiI under conditions of in. Thereafter, a glazed alumina substrate was produced by firing in air at 900° C. for 30 minutes to form a glaze layer as heat storage N2. The appearance of the obtained glazed alumina substrate was good, and the adhesion between the glaze and alumina was also good.

In Example 2.3, the heating resistor 5? A protective layer covering JS4 is not formed, but if necessary, it may be formed using a vapor deposition method or the like.

Note that the structure and composition of the glazed substrate and thermal head manufactured according to the present invention are not limited to the above embodiments. In the embodiments, 96% alumina was used for the substrate, but other ceramic substrates such as zirconia could be used. It is also possible to do so. In addition, although the electrodes were formed using the photo-edge puffer method and printing method, they can also be formed using other methods such as vapor deposition and sputtering, and the electrode material is not limited to gold or copper. The resistor may be of a thin film type or a thick film type such as a glazed resistor, and the method of forming the heating resistor and protective layer is not limited to vapor deposition or printing. is P
BMA is used, and the insulator raw material powder is borosilicate lead glass frit or An! ,O.

(55% by weight) + S i Ox (24% by weight) I
B, 0° (2.4% by weight), Na 20 (1.2% by weight), Ni20 (0.8% by weight), CaO (3.2% by weight), Mg0 (1.2% by weight) , PbO(7,
2% by weight), DBP as a plasticizer, and MEK as a solvent. However, the raw materials for the green sheet are not limited to these. For example, polyvinyl butyral (PVB) is used as a thermoplastic resin. ), dioctyl phthalate (DOP) as a plasticizer, barium borosilicate glass frit as the raw material powder for the m-rim body, and toluene as the solvent.

Effects of the Invention As described above, the present invention provides a thermal head using a process of hot pressing a green sheet using a thermoplastic resin as a resin binder or a green sheet laminated with T-pole material onto a sintered substrate, and then firing the green sheet. By manufacturing a heat storage layer that affects printing quality and thermal performance, it is possible to uniformly and easily form a heat storage layer of any thickness, thereby providing a high-quality thermal head with less variation in resistance value and reducing manufacturing man-hours. reduction can be achieved. Furthermore, the present invention can easily produce a glazed substrate with a uniform glaze thickness.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of an example of a planar thermal head manufactured according to the first embodiment of the present invention, and FIG. 2 is a configuration diagram of an example of an end-face type thermal head manufactured according to the second and third embodiments of the present invention. FIG. 3 is a configuration diagram of an example of a conventional planar thermal head, FIG. 4 is a block diagram showing an example of the manufacturing process of the conventional planar thermal head shown in FIG. 3, and FIG. FIG. 6 is a block diagram showing an example of the manufacturing process of the end-face type thermal head shown in FIG. 5. FIG. l...Substrate, 2...Heat storage layer, 3...
...Common electrode, 4...Individual electrode, 5...
...Heating resistor, 6...Protective layer, 7...
・Thickness of heat storage layer t, 8... Laser cut groove, 9
...... M thermal layer formation, 10... Screen printing, 11... Baking, 12... Individual electrode formation, 13... Common and Individual electrode formation, 14
..... Electrode protective layer formation, 15 .... End face cutting, 16 ..... Heating resistor formation, 17 ....
- Cut heating resistor, 18... Form protective layer.

Claims (5)

[Claims] (1) A method for manufacturing a thermal head, comprising the steps of bonding an insulating green sheet using a thermoplastic resin as a resin binder to a pre-sintered substrate by hot pressing, and firing the same. (2) The method for manufacturing a thermal head according to claim (1), wherein the portion formed by the insulating green sheet is a heat storage layer. (3) Claim using a pre-sintered substrate on which an electrode layer is formed (
1) The method for manufacturing the thermal head described above. (4) The method for manufacturing a thermal head according to claim (1), wherein the insulating green sheet is a laminate with an electrode material. (5) A method for producing a glazed substrate, comprising the steps of bonding an insulating green sheet using a thermoplastic resin as a resin binder to a pre-sintered substrate by hot pressing, and firing the same.