JPH0316746A - Substrate and thermal head having the same substrate - Google Patents

Abstract

PURPOSE:To obtain a substrate having superior surface smoothness, physical and chemical stability, and easily controllable thermal conductivity by a method wherein, in a laminated material consisting of an adhesive layer on a metal substrate and a planar glass, the thermal expansion coefficients are made consistent with each other. CONSTITUTION:Lead glass powder (an expansion coefficient of 110X10<-7>) is printed on a stainless steel plate 1 (an expansion coefficient of 114X10<-7>) together with an organic binder and burned to form an adhesive layer 2. Furthermore, thereon a soda-lime glass 3 (an expansion coefficient of 110X10<-7>) superior surface smoothness (average roughness height in the center line, Ra of 0.006) is disposed, burned, and bonded. In a thermal head using a substrate produced in this manner, the patterning and etching of electrodes 4 and heating elements 5 is remarkably enhanced, thus resulting in an improved pattern accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a substrate used in a thermal head, etc., and an article using this substrate. This will be explained by taking as an example an insulated hole-hole substrate for a thermal head, as shown in FIG. As for the manufacturing method of this substrate, first, the prepared glass frit is ground in a ball mill to form a slurry for electrophoretic electrodeposition (electrodeposition) with an average particle size of 2 to 3 μm. A direct current voltage is applied between the counter electrode and the metal substrate 1, and the charged glass frit particles are electrolyzed onto the metal substrate 1.
The center line average roughness Ra is 0.05 to 0.08 μm, and it is different from the conventional hollow substrate (Ra; 0.15 to 0.3, u
Problem to be Solved by the Invention Even though the surface of the substrate is extremely smooth compared to the electrode 4 shown in FIG.
In the process of patterning the heating resistor 5 and overcoat layer 6 to form the conductive circuit of the thermal head, the surface smoothness of the substrate is insufficient, making it impossible to form a fine pattern with high accuracy. There is also the problem that the thermal conductivity of the substrate is extremely difficult to control due to the reaction between the resistor 5 or overcoat layer 6 and other structural materials and the hollow substrate, making it impossible to form a thermal head with good characteristics. Means for Solving the Problems In order to solve the above problems, the present invention has a laminated structure consisting of an adhesive layer and a sheet of glass on a metal substrate, and the thermal expansion coefficients of the laminated structures are respectively The substrate of the present invention has a laminated structure consisting of an adhesive layer and a sheet of glass on a metal base, and the coefficients of thermal expansion of the laminated structures are matched, respectively. Excellent surface smoothness of the substrate
As shown in FIG. 1, a substrate with a thickness of 2 mm can be obtained. stainless steel plate 1
(Expansion coefficient 114X 10-') and glass transition point 40
Printing L,. After baking at a temperature of 800°C for 20 minutes, a 40 μm thick adhesive layer 2 is formed, and on top of that, a 50 μm thick adhesive layer 2 with an excellent surface smoothness and a center line average roughness Ra of 0. 006) Soda lime glass (expansion coefficient 1
10X 10-') was baked at 800°C for 10 minutes, and a plate-shaped glass 3 made of soda-lime glass was glued onto the substrate thus created to form the structure shown in Figure 1. A thermal head with a cross section was prototyped, and 1 and 4 were electrical symbols, 5 was a heating resistor, and 6 was an overcoat layer.The patterning and etching of the electrodes 4 and heating resistor 5 were also very good, compared to the conventional structure. The pattern accuracy is improved compared to ゛.
Second Example> As in the first example, a stainless steel plate 1 with a thickness of 2 mm (
Expansion coefficient 114 x 10-') and glass transition point 405
t, lead-based glass powder (expansion coefficient 110x 10-▼) with a softening point of 520°C and a particle size of 10 μm or less, an organic binder of 5 wt%, and stainless steel fine powder (particle size of 10 μm or less) 1
Printing after mixing with 0wt% L 20 at a temperature of 800℃
An adhesive layer 2 of 40 μm thickness was formed by baking for a minute, and on top of that was formed a soda lime glass (expansion coefficient 110X to -') installed L, 10 at 800℃
Minute baking Plate glass 3 different from soda lime glass
1. On the substrate thus prepared, a thermal head having the cross section shown in Fig. 1 was fabricated as a prototype, and the patterning and etching of the electrode 4 and heating resistor 5 were very good. 3rd Embodiment> Similar to the 1st embodiment, a stainless steel plate 1 with a thickness of 2 mm (
Glass transition point 390a on expansion coefficient 114X10-▼〉
Lead-based glass powder (expansion coefficient 118 x 10-') with a softening point of 450°C and a particle size of 10 μm or less, 5 wt% organic binder, and stainless steel fine powder (particle size of 10 μm or less)
10wt%. Mix with an appropriate amount of organic solvent (proparol), spray L, and burn for 20 minutes at a temperature of 650°C.
A 40 μm adhesive layer 2 is applied 1, and on top of that is a 50 μm thick soda lime glass with excellent surface smoothness (center line average roughness Ra of 0.006) (expansion coefficient 11).
0XIO1▼) was installed IA and burned at 650℃ for 10 minutes, and a certain plate-shaped glass 3 was glued from soda lime glass.
We fabricated a prototype thermal head with the structural cross section shown in Figure 1 on the substrate created in this way, and found that the patterning and etching of the electrodes 4 and heating resistor 5 were very good, compared to the conventional structure. Fourth Embodiment In order to improve the pattern accuracy compared to the previous example, a 2 mm thick stainless steel plate l (
Expansion coefficient 114X 10-') and glass transition point 390
'tl,, 5wt of lead-based glass powder (expansion coefficient 118X 10-') with a softening point of 450°C and a particle size of 10 μm or less
% organic binder, stainless steel fiber (diameter 10μ, length 1mm or less) 10 wt! %. After mixing with an appropriate amount of organic solvent (proparol), Soubrei L, 65
Baked for 20 minutes at a temperature of 0°C. Adhesive layer 2 of 40 μm.
Further, on top of that, soda lime glass (expansion coefficient 110 x 10-') with a thickness of 50 μm and excellent surface smoothness (center line average roughness Ra of 0.006) was installed L-6
After baking at 50°C for 10 minutes, a plate-shaped glass 3 made from soda-lime glass was adhered, and a thermal head having the cross-section shown in Figure 1 was fabricated on the thus prepared substrate. The patterning and etching of the electrode 4 and heating resistor 5 are also very good, and the pattern accuracy is improved compared to the conventional structure. Steel plate 1 (
Apply a layer of epoxy resin and fine silica powder (expansion coefficient: 115 x 10-') onto the surface (with an expansion coefficient of 114 x 10-'), form an adhesive layer 2 with a thickness of 30 μm, and then smooth the surface with a thickness of 50 μm on top. Excellent center line average roughness Ra of 0. 006) Soda lime glass (expansion coefficient 1
10 x 10-') was baked at 250°C for 10 minutes, and the structure shown in Figure 1 was placed on the substrate made in this way, on which a certain plate-shaped glass 3 was glued from soda-lime glass. The patterning and etching of the electrode 4 and the heating resistor 5 of which a prototype thermal head having a cross section was made was very good, and the pattern accuracy was improved compared to the conventional structure.6th Example〉 First Example Stainless steel plate 1 with a thickness of 2 mm similar to (
Expansion coefficient: 114 x 10-') Washed with water Acid round nickel plated, washed with water and pretreated, average particle size is 5μ
glass transition point 390a, softening point 450°C, lead-based glass powder (expansion coefficient 118 x 10''') and proparol solution. A 30 μm thick glass powder was electrodeposited on a stainless steel plate, dried at room temperature, and then burned at a temperature of 650°C for 20 minutes. Soda lime glass (expansion coefficient: 110 x 10-') with excellent surface smoothness (center line average roughness Ra: 0.006) was installed and annealed at 650°C for 10 minutes to produce a plate-shaped glass 3 from soda lime glass. A prototype thermal head having the cross section shown in Fig. 1 was fabricated on the thus-produced substrate bonded to the substrate. Comparative example with improved pattern accuracy compared to a certain one > 2 mm thick stainless steel plate l (expansion coefficient l14 x 1
0-') was taken off. Water Nine acid pills were nickel plated, washed with water, and pretreated. Immersed in a slurry consisting of glass particles with an average particle size of 2.5 μm, and the k transition point was 390'u.
Lead-based glass powder with a softening point of 450℃ (expansion coefficient 118X)
10-') and a proparol solution, and a DC voltage was applied to the counter electrode and the stainless steel plate 1 to electrodeposit crystalline glass particles having a thickness of 150 μm as shown in Table 1 on the stainless steel plate 1. Dry this at room temperature.
A substrate was formed by baking at a temperature of 900°C for 20 minutes. Then, as shown in Fig. 2, an electrode 4, a heating resistor 5, and an overcoat layer 6 were formed on this substrate, and a thermal head was prototyped. Table 1 Table 2 Table 3 Regarding the above Examples 1 to 5 and comparative examples, center line average roughness R on the substrate surface, resistance value variation of the heating resistor 5 of the thermal head, thermal efficiency of the thermal head (OD concentration 1.0
The results are shown in Tables 2 and 3.

Effects of the Invention As explained above, according to the present invention, a substrate with excellent surface smoothness, physicochemical stability, and easy control of thermal conductivity can be obtained, and when used as a thermal head, there is no resistance value variation. It can also reduce and improve thermal efficiency

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a thermal head using a substrate according to an embodiment of the present invention, and Fig. 2 is a cross-sectional view of a thermal head using a conventional substrate. ...Adhesive material #3...
Plate-shaped container

Claims (4)

[Claims] (1) A substrate characterized in that it has a laminated structure consisting of an adhesive layer and a plate-shaped glass on a metal substrate, and the thermal expansion coefficients of the laminated structures are matched. (2) The adhesive layer is formed by spraying, printing, or electrophoretic electrodeposition, and is made of glass such as lead-based glass or resin, which has a lower softening point than sheet glass. The substrate according to claim 1. (3) The substrate according to claim 2, wherein the adhesive layer contains metal powder or metal fibers having good thermal conductivity. (4) A thermal head characterized by using a substrate having a laminated structure consisting of an adhesive layer and a plate-shaped glass on a metal base, and in which the coefficients of thermal expansion of the laminated structures are matched.