JP3197257B2 - Glaze substrate for thermal head and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glaze substrate for a thermal head used for a facsimile, a thermal printer, and the like.

[0002]

2. Description of the Related Art Conventionally, as a printing mechanism of a facsimile, a thermal printer, or the like, for example, a thermal head has been known. This thermal head includes a glaze substrate having a glassy glaze layer formed on a ceramic substrate. It is used.

As the above glaze substrate, for example,FIG.
As shown in (a), on a flat ceramic substrate P1
Then, the glaze layer P2 is arranged in a belt shape to form a projection P3.
A heating element is known on the surface of the projection P3.
P4 is formed, and a conductive pattern is formed on the ceramic substrate P1.
Line P5 is wired.

Further, as shown in FIG. 4B, the entire surface of a ceramic substrate P7 having a projection P6 is covered with a glaze layer P7.
8, a projection P9 is formed, and a heating element P10 is formed on the surface of the projection P9.
The conductive pattern P1 is formed on the flat plate portion P11 of the glaze layer P8.
2 is wired.

[0005]

However, the above-mentioned prior art has not been sufficient because of the following problems. That is, in recent years, the demand for refinement of equipment has been increasing, and the glaze layer P is formed on the flat ceramic substrate P1.
2, the projection P3 is formed by the glaze layer P
When baking is performed, a phenomenon called so-called “sinking” occurs in which the end portion of the glaze layer P2 shrinks, whereby the protrusion P3 is formed.
There has been a problem in the linearity and dimensional accuracy of the device. Further, high precision is also required for the above wiring, and the conventional conductive pattern P5 is directly formed on the ceramic substrate P1 having a rough surface.
In the case of wiring, there has been a problem that higher precision and homogenization cannot be achieved.

In the case where the glaze layer P8 is formed on the ceramic substrate P7 having the projections P6, the smoothness is improved by covering the entire surface of the ceramic substrate P1 with the glaze layer P8. Due to the softening of P8, the projection P9 is easily spread, and there is a problem that a projection P9 having a sufficient shape and a sufficient height and width cannot always be formed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a glaze substrate for a thermal head, which has a protruding portion having a suitable shape and which can perform precise and uniform wiring, and a method of manufacturing the same. .

[0008]

Means for Solving the Problems (1) In order to solve the above-mentioned problems, the invention of claim 1 comprises a first glaze layer covering the surface of a ceramic substrate, and a first glaze layer having a thickness of 5%.
0 ℃ above the softening point is low at least an end portion is the first glaze layer which is formed in a convex-shaped second glaze layer and the Bei <br/> example Rutotomoni, the first glaze layer Rare earth element
The second group including at least one of La and Y;
The lasing layer does not contain any of the rare earth elements La and Y.
Roast that the gist of the glaze substrate for a thermal head according to claim.

According to the first aspect of the present invention, the first glaze layer having a high softening point covers the surface of the ceramic substrate.
On top of this first glaze layer, 5
The second glaze layer having a softening point lower than 0 ° C. is formed in a convex shape. Thereby, since the end of the second glaze layer is not directly in contact with the ceramic substrate, but is on the first glaze layer, "sink" does not occur when firing the second glaze layer. . Therefore, the second glaze layer is excellent in straightness and the shape of the convex portion is clearly preserved.

(2) The second aspect of the present invention is to provide at least one of the rare earth elements La and Y covering the surface of the ceramic substrate.
After forming the first glaze layer including the first glaze layer by firing, a rare earth element having a softening point lower than that of the first glaze layer by 50 ° C. or more.
A composition to be a second glaze layer containing neither La nor Y is formed in a convex shape so that at least an end is disposed on the first glaze layer, and then the first glaze layer is formed. A method for manufacturing a glaze substrate for a thermal head, characterized in that the glaze layer is fired at a temperature lower by at least 100 ° C. than the firing temperature of the glaze layer.

According to the second aspect of the present invention, the second glaze layer having a softening point lower by 50 ° C. or more than the first glaze layer is formed on the first softened glaze layer fired at a high temperature. By forming the object in a convex shape and firing at a temperature 100 ° C. or more lower than the firing temperature of the first glaze layer,
The devitrification caused by the reaction between the two glaze layers is prevented. Further, since the firing temperature of the second glaze layer is low, the firing can prevent the softening of the first glaze layer, whereby the shape of the convex portion is clearly preserved.

Here, it is more preferable that the temperature difference of the softening point between the first glaze layer and the second glaze layer is 100 ° C. or more, since a convex portion with a clear shape is formed. . As the ceramic substrate, alumina, aluminum nitride, silicon nitride, silicon carbide, mullite, or the like can be used.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, examples (embodiments) of the embodiments of the present invention will be described. Here, the first to third embodiments are directed to the first glaze having a high softening point on a ceramic substrate. after forming a layer with a uniform thickness, Ru der those provided with the second glaze layer having a low softening point to form the protrusion. (First to Third Embodiments) First, materials and the like used in these embodiments will be described.

As the ceramic substrate on which the first and second glaze layers are formed, a substrate containing 97% by weight of alumina is used. In addition, aluminum nitride, silicon nitride, silicon carbide, mullite or the like is used. it can. Also, the first
Alternatively, the paste to be the second glaze layer is prepared by first adjusting the raw materials of glass so as to have the composition shown in Table 1 below.
After melting at a temperature of from 1500C to 1500C, the glass frit is produced by quenching in water. Next, the glass frit is pulverized and mixed with an ethylcellulose-based binder to produce a paste. In Table 1 below, the glaze composition used in Comparative Examples described later is also described.

[0015]

[Table 1]

(First Embodiment) As shown in FIG. 1, a glaze substrate 1 used in a thermal head according to the present embodiment has a ceramic substrate 2 on a first substrate having the composition of Sample No. 1 in Table 1 above. Glaze layer 3 is 50
It is formed uniformly with a thickness of μm. Further, a second glaze layer 4 having the composition of Sample No. 2 is provided on the surface of the first glaze layer 3, and the second glaze layer 4 has a convexity of 40 μm in height and 1.0 mm in width. A projection 5 is formed. A heating element 6 is formed on the surface of the projection 5, and wirings and the like are formed in close contact with the flat surface of the first glaze layer 3 by etching or the like.

In order to manufacture this glaze substrate 1, first, as shown in Table 2 below, a first
Apply the paste of sample No. 1 to become the glaze layer 3 of
The first glaze layer 3 having a uniform thickness was formed by firing at 1250 ° C. for 2 hours. Next, on the surface of the first glaze layer 3, the paste of the above-mentioned sample No. 2 was applied in a strip shape with a width of 1 mm, and baked at 1020 ° C. for 2 hours to form a projection 5.

The glaze substrate 1 manufactured as described above
Since the second glaze layer 4 is formed on the first glaze layer 3, “sink” is 0.1 mm even by firing.
The following hardly occurs, and the linearity is not impaired. Furthermore, the difference in softening temperature is as large as 170 ° C,
In addition, since the difference in the firing temperature is set to be as large as 230 ° C., the first glaze layer 3 is softened when the second glaze layer 4 is fired and reacts with the second glaze layer 4. There is no devitrification, and the first glaze layer 3 does not soften and the second glaze layer 4 sinks.

That is, as in this embodiment, the softening point Ts of the first glaze layer 3 is
If the temperature is higher than s by 100 ° C. or more, the firing temperature of the second glaze layer 4 is set to a temperature range in which the first glaze layer 3 does not have fluidity, that is, a temperature range in which a difference in firing temperature of 100 ° C. or more occurs. it can. Therefore, it is possible to prevent the occurrence of devitrification and the collapse of the shape of the projection 5.

If the difference in softening point Ts between the second glaze layer 4 and the first glaze layer 3 is 100 ° C. or more, or if the difference in firing temperature is 100 ° C. or more, the two glaze layers 3 , 4 can be significantly combined. For example, as the second glaze layer 4 constituting the protrusion 5, a material having excellent heat resistance and heat storage properties is employed, while the flat first glaze layer 3 has excellent smoothness and etching resistance. Any material can be selected, such as adoption of a material.

(Second Embodiment) As shown in FIG. 2, a glaze substrate 11 of this embodiment has a ceramic substrate 12 on which a first glaze layer 13 having the composition of sample No. 1 has a uniform thickness. Although it is formed to have a thickness of 40 μm, it is greatly different from the above-described first embodiment in that a band-like portion 15 in which the first glaze layer 13 is not formed is provided in a part. Then, a second glaze layer 14 having the composition of Sample No. 3 is provided on the belt-like portion 15, and the second glaze layer 14 forms the convex protrusion 16 having a height of 60 μm and a width of 10 mm. ing. When the second glaze layer 14 is formed on the strip 15, the end of the second glaze layer 14 needs to be formed on the end of the first glaze layer 13. .

When the glaze substrate 11 is manufactured, as shown in Table 2, the first glaze layer 13 is first baked at 1250 ° C. for 2 hours, and then the second glaze layer 15 is heated at 930 ° C. For 2 hours. The glaze substrate 11 manufactured as described above has the same functions and effects as those of the first embodiment.

(Third Embodiment) The glaze substrate 21 of the present embodiment is almost the same as that of the first embodiment, but the composition of the material used is different. That is, as shown in FIG. 3, a first glaze layer 23 having the composition of Sample No. 4 is formed on the ceramic substrate 22 with a uniform thickness, and the projections 24 are further formed on the first glaze layer 23.
A second glaze layer 25 having a composition of Sample No. 2 is provided.

When the glaze substrate 21 is manufactured, first, as shown in Table 2, the first glaze layer 23 is formed.
Was fired at 1300 ° C. for 2 hours, and then the second glaze layer 25 was fired at 1020 ° C. for 2 hours. Although the glaze substrate 21 manufactured in this manner had slightly crystallized, the surface was smooth and the second glaze layer 25 was not devitrified.
The shape of the projection 24 was also well maintained.

Next, a comparative example will be described. (First Comparative Example) The glaze substrate (not shown) of this comparative example is almost the same as the configuration of the first embodiment, but differs in the composition of the material used.

That is, the sample No. 1 was placed on the ceramic substrate.
Is formed with a uniform thickness, and a second glaze layer having a composition of Sample No. 5 serving as a protrusion is provided on the first glaze layer. When manufacturing this glaze substrate, as shown in Table 2, first, the first glaze layer was fired at 1250 ° C. for 2 hours, and then the second glaze layer was fired at 1150 ° C. for 2 hours.

The glaze substrate manufactured in this manner is
Since the softening point Ts of the first glaze layer is 970 ° C. and the softening point Ts of the second glaze layer is 940 ° C. and the temperature difference is 50 ° C. or less, the reaction occurs because both glaze layers soften and mix. And devitrification occurs around the interface between the first glaze layer and the second glaze layer, and the crystal becomes non-smooth due to the generation of the crystal (projection of the crystal), and the width and thickness of the projection are precisely adjusted. Problems such as the inability to form them will occur.

(Second Comparative Example) The glaze substrate of this comparative example has substantially the same configuration as that of the first comparative example, except that the glaze compositions of the first glaze layer and the second glaze layer are the same. Are very different.

That is, the sample No. 5 was placed on the ceramic substrate.
Is formed with a uniform thickness, and a second glaze layer having a composition of Sample No. 5 serving as a protrusion is provided on the first glaze layer. When manufacturing this glaze substrate, as shown in Table 2, first, the first glaze layer is fired at 1250 ° C. for 2 hours, and then the second glaze layer is fired at 1150 ° C. for 2 hours.

The glaze substrate thus manufactured is
Since the softening points Ts of the first glaze layer and the second glaze layer were the same, the boundary became unclear and a clear projection shape could not be maintained.

[0031]

[Table 2]

Although the embodiments of the present invention have been described above, the present invention is not limited to such embodiments at all, and it is needless to say that the present invention can be implemented in various modes without departing from the gist of the present invention. It is.

[0033]

According to the first aspect of the present invention, since the second glaze layer is formed on the first glaze layer, a clearly shaped convex portion is formed. Further, at that time, there is a feature that a convex portion having high linearity and accuracy is formed without sink marks.

The material of the second glaze layer according to claims 1 and 2 is, for example, excellent in heat storage properties, but is difficult to adapt to ceramic substrates in terms of thermal expansion and the like, and has been difficult to use conventionally. There is an advantage that can also be used. Further, the surface of the ceramic substrate is claimed
The first glaze layer can dramatically improve the surface roughness of the ceramic substrate surface, thereby eliminating the need for surface processing on the ceramic substrate. Can be easily manufactured.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a glaze substrate according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a glaze substrate according to a second embodiment.

FIG. 3 is a sectional view showing a glaze substrate according to a third embodiment.
You.

FIG. 4 is a cross-sectional view showing a conventional glaze substrate.

[Explanation of symbols]

1, 11, 1, 1 ... Glaze substrate 2, 12, 2 2 ... Ceramics substrate 3, 13, 2 3 ... First glaze layer 4, 14, 25 5 ... Second glaze layer

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-60-42069 (JP, A) JP-A-62-153178 (JP, A) JP-A-60-155550 (JP, A) JP-A-58-58 179668 (JP, A) JP-A-62-138257 (JP, A) JP-A-62-259874 (JP, A) JP-A-63-3971 (JP, A) Actually open JP-A-62-102640 (JP, U) Shokai 59-155139 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B41J 2/335

Claims (2)

(57) [Claims] A first glaze layer covering a surface of a ceramic substrate; a first glaze layer having a softening point lower than that of the first glaze layer by at least 50 ° C. and at least an end formed on the first glaze layer; Rutotomoni comprising a second glaze layer, wherein the the first glaze layer of La and Y of rare earth elements less
At least one, and the second glaze layer is rarely contained.
A glaze substrate for a thermal head, wherein the glaze substrate does not contain any of the earth elements La and Y. 2. A rare earth element covering the surface of a ceramic substrate.
After firing and forming a first glaze layer containing at least one of elemental La and Y, the first glaze layer
Any of La and Y rare earth elements having a softening point of 0 ° C. or higher
The second glaze layer- free composition is formed in a convex shape so that at least the ends are disposed on the first glaze layer, and then the firing temperature of the first glaze layer is higher than 100%. A method for producing a glaze substrate for a thermal head, characterized in that the substrate is fired at a temperature lower than or equal to ° C.