JPH0382555A - Production of thermal head - Google Patents

Abstract

PURPOSE:To stabilize the raised shape of second glaze layers even under proximate forming conditions by a method wherein a glaze layer surface between second glaze layers which have been fused and cured to be proximate and adjacent to each other are disconnected at a part of a second slit-form opening. CONSTITUTION:On the main surface of a substrate 3, a first glass paste 11 is applied by screen printing with a pattern that a plurality of first slit-form openings 13-1, 13-2 are formed in proximity and parallel to each other and a second slit-form opening 17 is also formed between both the openings. Next, a second glass pastes 12-1, 12-2 having a softening temp, higher than that of the first glass paste are printed with independent band-form patterns that the first slit-form openings are respectively covered but the second slit-form opening is not covered. The width of the second glass paste band is minutely larger than that of the slit. After the printing process, the second glass pastes are thermally treated at a temp, higher than the softening temp, thereof to be fused and cured. After the thermal treatment, small glaze recesses 4-1, 4-2 are formed on the skirts of raised second glaze layers 2-1, 2-2. On the other hand, there is no recess in the vicinity of a slit-form groove 7 provided between the second glaze layers.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing a thermal head having a convex glaze layer, and particularly relates to a method for manufacturing a thermal head having a convex glaze layer on the main surface of one substrate. The present invention relates to a method for manufacturing a thermal head in which a plurality of parallel rows of strip-shaped glaze layers are formed in close proximity.

[Summary of the invention]

The present invention prints at least two kinds of glass pastes having different softening temperatures in an appropriate pattern, and heat-treats the paste to form a plurality of protruding band-shaped glaze layers arranged in parallel in a stable shape. The method is characterized by providing slit-like openings so that the surface of the glaze layer is discontinuous between a plurality of adjacent convex glaze layers, and using at least two kinds of glass pastes described above in an appropriate pattern. By forming a glaze layer with
In the molten state during heat treatment of the glaze layer,
The two protruding band-shaped glaze layers adjacent to each other can be stably formed in close proximity without merging, and the substrate surface other than the convex glaze layer can be smoothly formed. The present invention provides a technique for coating with an insulating glaze layer, and is therefore applicable to cases in which a plurality of edge-type thermal heads having a convex glaze layer on the edge portion of the main surface of a thermal head substrate are obtained from one substrate, The present invention provides an easy manufacturing means for manufacturing a multi-array type thermal head having a plurality of convex glaze layers and a heating element array on each convex glaze layer.

[Conventional technology]

When obtaining multiple edge-type thermal heads from one substrate, which have a convex glaze layer on the main surface edge of the thermal head substrate, or when having multiple convex glaze layers and generating heat on each convex glaze layer. In the formation of a glaze layer in the manufacture of a multi-array type thermal head having a glass space array, as shown in FIGS. There is a method of printing two pieces of glass paste (101) close to each other in parallel, and then heat-treating the glass paste to form a glaze layer (103) having a raised arc-shaped cross section as shown in FIG.

For example, when obtaining the edge-type thermal head from the glaze substrate, after forming a heating element etc. on the glaze layer (103), the substrate (102) is placed between the glaze layers.
Divide.

[Problem to be solved by the invention]

However, if a band-shaped glaze layer is simply formed on the ceramic as described above, the surface of the substrate without the glaze layer is porous and has irregularities of about 1-degree, so short circuits and disconnections occur when forming electrodes. Such defects were likely to occur. In addition, subtle differences in wettability between the main surface of the substrate and the molten glass can cause defects such as variations in the width of the glaze layer and waviness of the surface of the glaze layer, resulting in adjacent glaze layers coalescing. Ta.

[Means to solve the problem]

The present invention was made in view of the above-mentioned problems, and is a manufacturing method that includes a step of printing at least two kinds of glass pastes having different softening temperatures in an appropriate pattern and heat-treating this. That is, the first glass paste is printed in a pattern having a plurality of adjacent parallel first slit-like openings and a second slit-like opening between the adjacent first slit openings. A step of applying a second glass paste having a higher softening temperature than the first glass paste to cover each of the plurality of first slit-like openings individually, and applying a second glass paste having a softening temperature higher than that of the first glass paste to cover each of the plurality of first slit-like openings, and applying a second glass paste to a plurality of band-like pastes that do not cover the second slit-like openings. A process of printing with a pattern to be patterned;
The method includes a step of melting and hardening the first and second glass pastes by heat treatment, and the method includes a step of melting and hardening the first and second glass pastes, and a slight depression is formed near the contact area between the first glass paste and the second glass paste after melting and hardening. , the surface of the glaze layer between the second adjacent glaze layers is discontinuous at the portion where the second slit-shaped opening is located. That is.

[Effect]

In the combination of the glass pastes, by providing the second slit-like opening in the pattern of the first glass paste between the adjacent second glass pastes, the two adjacent second glass pastes are In the glaze layer, when the glass is melted during heat treatment, surface tension acts in the direction of forming a bulge in each glaze layer, that is, in the direction in which the molten glass gathers around each second glaze layer, causing the two glaze layers to coalesce. The second slit-shaped opening of the first glass paste, which does not act in the direction, is much less likely to be crushed by the surface tension during melting, compared to the conventional case. The present invention is a method for making the raised shape of the second glaze layer stable even under conditions of close formation.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1(^) is a perspective view of a glazed substrate during processing of a thermal head according to the manufacturing method of the present invention.
B) is a cross-sectional view thereof. Substrates to avoid from Ceramink (
3), a first glaze layer fil and a band-shaped second glaze N(2) forming a convex bulge in contact with the first glaze layer are formed. Most of the main surface of the substrate (3) is covered with the first glaze layer and the second glaze layer, and the surface is a smooth and continuous surface made of amorphous glaze. Between the second glaze layers (2) provided in parallel in close proximity, there is a slit-shaped groove (2) in which the surface of the substrate (3) is exposed.
7).

To explain the process of obtaining the above glazed substrate, first, the second
As shown in the perspective view in Figure (A) and the cross-sectional view in Figure 2 (B), there are a plurality of first slit-shaped openings (13-1) (13-2) close to the main surface of the substrate (3). are provided in parallel, and a second slit-shaped opening α sandwiched between the first slit-shaped opening
A pattern in which D is also provided, and the first glass paste Ql)
3 (A) is applied by screen printing.
), and as shown in the cross-sectional view in FIG. A second glass paste (12-1) having a softening temperature higher than that of the first glass paste, which is an independent band-like pattern that is not covered.
12-2) is printed. The width of the band of the second glass paste is slightly wider than the width of the slit.The first glass paste and the second glass paste can be printed in any order, but the second glass paste is printed in the second slit. When the width of the opening is narrower than the first slit opening, it is preferable to print the first glass paste first so that the second slit opening pattern is less likely to be crushed during printing and heat treatment. After the printing process, heat treatment is performed at a temperature higher than the softening temperature of the second glass paste to melt and harden it. Regarding the softening temperature of glass paste, see the first and second
The difference between the two glass pastes is 50~200℃, and the heat treatment temperature is 200~200℃ higher than the softening temperature of the second glass paste.
Conditions higher by 400° C. give more favorable results for glass crystallization and the shape of the glaze layer.

By the way, in FIG. 1(B), (4-1) (4-2
) is the second glaze I'! (2-1) A slight indentation in the glaze that occurs at the base of the bulge in (2-2), and the depth and location of the indentation vary depending on the printing dimensions of the glass paste, the forming conditions of the glass material used, etc. However, the dents are formed in the glaze layer in the configuration of the present invention. On the other hand, there is no depression around the slit-shaped groove (7) sandwiched between the second glaze layers.

The slit-like grooves and the depressions will be explained in more detail using FIGS. 4(A) to 4(C) and 4(AA) to (CC). FIGS. 4(A) to 4(C) are cross-sectional views of a substrate printed with first and second glass pastes in forming a glaze substrate, and show slit-shaped openings in the printing pattern of the first glass paste ( 13-1) (13-2
) during the interval (5), and the interval between the strip patterns (121) < 12-2) in the printing of the second glass paste)
FIG.

FIGS. 4(AA) to (CC) are cross-sectional views of glazed substrates produced as a result of heat-treating the glass pastes shown in FIGS. 4(A) to (C). Accordingly, the second glaze layers (2-1) (2-2) approach each other, and the independent depressions (6-1) (6-2) between these two second glaze layers become shallower. Finally, as shown in Figure 4 (CG), the depression disappears and the groove (7)
Immediately apply the second glaze layer (2-1) (2
-2) The excitement will end.

When the groove (7) and the second glaze layer are separated from each other as shown in FIG. It is less susceptible to the strong surface tension that acts around the layer, and therefore the first
Depending on the surface tension of the glaze itself and its wettability with the substrate (3), the first glaze layers on both sides of the groove (7) tend to coalesce. However, in the positional relationship where the depression disappears or becomes shallow as shown in FIG. 4 (CG), the area around the groove (7) is also affected by the strong surface tension acting around the second glaze layer. The possibility of filling the groove (7) is reduced. Therefore, the cross-sectional shapes of the two second glaze layers maintain a good convex shape.

As shown in FIG. 4 (CC), the spacing fat is such that the second glaze layer is reliably separated and maintains a good convex shape.
The value of (b) is the printing thickness of the first glass paste,
It depends on the first slit-like opening width (C), the second slot-shaped opening width tel, and the band-like pattern width fdl of the second glass paste, and also on the type of glass material. The second slit-like opening width (81) is required to be at least 0.20 in order to reliably separate the adjacent second glaze layer. (For e1 or more, the maximum is approximately 2.5fi.As a result, the distance between the highest parts of the convexities of the second glaze layer (illusion) is
．． In the case of 5fi, 1.0 to 2. It is about ON. The various dimensions described above depend on the type of thermal head to which the present invention is applied;
Depending on the application, the above 1. It may be selected as appropriate along with the thickness or height of the second glaze layer.

FIG. 5 is a cross-sectional view showing an example of steps after glaze formation in the manufacturing method of the present invention.

In FIG. 5, the second glaze layer (2-1) (2-2
), a heating element (to) is formed by forming a resistive film and patterning, and after forming an electrode el+ in the same way, a snap line (to) provided on the back surface of the substrate (3) is used to Alternatively, insert a snap line (2) at an accurately positioned location using a diamond blade, etc., and insert the substrate into the slit-like groove (2) between the two glaze layers.
7) can be divided to obtain an edge-type thermal head. In this substrate division, since the division is performed using slit-like grooves in which no glaze layer is formed, there is an advantage that chipping of the glaze does not occur.

FIG. 6 is a perspective view of a thermal head to which the manufacturing method of the present invention is applied, in which two second glaze layers (2-1) and (2-2) are parallel to each other in the center of the main surface of the substrate (3). This is a multi-array type thermal head in which an array of heating elements (2) is formed on the glaze layer. Slit groove (7)
The bottom surface of the second glaze layer is 40~
Since the depth is 80 μm, a common electrode made of thick film conductive paste with a thickness of 30 μm can be provided in the groove (7).

In the above embodiment, two second glaze layers were provided close to each other, and FIGS. 7(A) and 7(B) are cross-sectional views of the substrate printed with glass paste, and the cross-sectional views of the substrate after heat treatment. As shown in the cross-sectional view, three or more second adjacent glaze layers can also be formed. In this case, the first slit-shaped openings (13-1) (13-2) (13-3) in the first glass paste Qll pattern, the second
a slit-shaped opening, and a second glass paste (
12-1) (12-2>(12-3)) is the same as the relationship in the above-mentioned example.As shown in FIG. 4(B), in the second glaze layer after heat treatment, A second glaze layer sandwiched on both sides by another second glaze layer (2-1) (2-2)
The glaze layer (2-3) is the first glaze TI! I(1
) Since there is no top-to-bottom contact, the cross-sectional shape is different, and if the printed pattern of glass paste is the same on both sides, there will be a difference in thickness. In the inventor's tests, the second glaze layer in the center tends to be thicker. In applications where the height is unified, the first slit-like opening width fc) of the first glass paste in FIG. 7(A) and the pattern width (dl) of the second glass paste should be Set and form narrower.

〔Effect of the invention〕

The effects of the present invention are listed below.

The shape of the glaze layer is stabilized when the band-shaped glaze layer with convex bulges is provided close to and parallel to the main surface of the substrate.

Since a desired location on the main surface of the substrate can be coated with the first glaze layer, if the substrate is ceramic, the surface can be smoothed and the patterning yield can be increased, and if the substrate is metal, it can function as an insulating coat.

By dividing the substrate in the slit-like grooves of the glaze layer,
No glaze chipping occurs.

[Brief explanation of drawings]

FIG. 1(A), FIG. 2(A), and FIG. 3(A) are perspective views of the glazed substrate during processing of the thermal head in the present invention, FIG. 1(B), and FIG. 2(B). , Figure 3(B) is
FIGS. 4A to 4C are cross-sectional views of a glazed substrate during processing of a thermal head in the present invention, and FIGS. 4A to 4C are cross-sectional views of a substrate printed with glass paste in forming a glazed substrate, CC) is shown in Fig. 4 (A) to (C
), FIG. 5 is a cross-sectional view of the substrate of the thermal head according to the present invention, FIG. 6 is a perspective view of the thermal head according to the present invention, and FIG. 7(A) ( B) is a cross-sectional view of the glazed substrate during processing of the thermal head in the present invention, FIG.
FIG. 9 is a perspective view of a glazed substrate during processing of a conventional thermal head. 1... First glaze layer 2.2-1.2-2.2-3... Second glaze layer 3... Substrate 4-1.4-2.6-1.6-2 ...glaze depression 7...slint-like groove 11...first glass paste 12-1, 12-2.12-3...second glass paste 13-1.13-2.13 -3...First slit-shaped opening 17...Second slit-shaped opening 20...Heating elements 23, 24...Snap line or more

Claims (1)

[Scope of Claims] A first glaze layer and a band-shaped second glaze layer protruding from the surface of the first glaze layer in contact with the glaze layer, on the main surface of one substrate. In the method of manufacturing a thermal head, a first glass paste has a plurality of first slit-shaped openings arranged in parallel in close proximity to each other, and the first glass paste has a plurality of first slit-shaped openings arranged in parallel in close proximity to each other, printing a pattern having second slit-like openings between the openings; applying a second glass paste having a higher softening temperature than the first glass paste to each of the plurality of first slit-like openings; a step of printing a plurality of strip patterns that do not cover the second slit-like opening; a step of melting and hardening the first and second glass pastes by heat treatment; and a step of printing a heating element and an electrode on the glaze layer. The glaze layer surface between the adjacent second glaze layers due to the melt hardening is discontinuous at the portion where the second slit-shaped opening is located. A method for manufacturing a thermal head.