JPH02212158A - Production of thermal head - Google Patents

Abstract

PURPOSE:To reduce a change of the contact efficiency with a transfer ribbon by printing crystallized glass paste at least in two rows when the glass paste is printed and further printing amorphous glass paste so as to cover the crystallized glass paste. CONSTITUTION:Crystallized glass pastes 4', 4' are parallelly printed in two rows so as to provide a predetermined distance and amorphous glass paste 5' perfectly covers the crystallized glass pastes 4', 4'. The amorphous glass paste 5' becomes almost flat at the upper part thereof because of amorphous glaze layers 4, 4 and a glaze layer 3 having an almost trapezoidal cross-section is constituted. The part held between the electrodes 7, 8 of a heating resistor 6 is positioned at the flat part of the glaze layer 3 and the contact efficiency with a transfer ribbon does not change very much.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a method for manufacturing a thermal head provided with a glaze layer.

(b) Prior Art FIG. 4(a) shows a cross-section of a main part of a γ!v11 type normal head with a glaze layer (rn). Reference numeral 12 is an insulating λ plate made of alumina ceramic or the like. Insulating substrate 12
A glass paste is printed on top and fired to form a glass glaze layer I3. This glass glaze layer 13
A heat generating resistor 16 is formed so as to straddle the insulating substrate 12, and an electrode 1 for energizing the heat generating resistor 16 is further formed on the insulating substrate 12.
7.18 is formed. Heat generating resistor 15 and electrode 1
7.18 are both patterned by applying photolithography. At this time, so that the heat generating resistor 16 and the glass glaze layer 13 have a predetermined positional relationship of 6°W, for example, the center of the heat generating resistor 1G
Care must be taken to ensure that it is at the top.

(C) Problems to be Solved by the Invention - H In the conventional thermal head 11, the heating resistor 16
Since photolithography is applied to the formation of the electrodes 17 and 18, their positional accuracy is extremely high. However, since the glass glaze layer 13 is formed by a method of printing and firing, the position tff cannot be made very high. Therefore, as shown in FIG. 4(b), the position of the glass glaze layer 13 is shifted, and the heating resistor 1
The center of the glass glaze layer 13 was shifted from the top of the glass glaze layer 13, which changed the efficiency of contact with the transfer ribbon or thermal recording paper, which could adversely affect printing quality.

The present invention has been made in view of the above, and is intended to provide a first method for manufacturing a thermal head in which the efficiency of contact with a transfer ribbon etc. is less affected even when the glass glaze layer is formed with some deviation. .

(d) Means for Solving the Problems In order to solve the above problems, the method for manufacturing a thermal head of the present invention includes printing glass paste on an insulating substrate, applying the glass paste, and then applying the glass paste as a glaze layer. in which a heating resistor is formed so as to straddle the glaze layer, and an electrode is further formed on the insulating substrate to make the heating resistor thinner, when printing the glass paste, at least This method is characterized by printing crystallized glass paste in two rows and further printing an amorphous glass paste so as to cover these crystalline 1L glass pastes.

(E) Function Crystallized glass paste does not easily lose its shape when fired, but it has the characteristic that the surface of the resulting glaze layer becomes sharp.

On the other hand, amorphous glass space 1- tends to flow when fired, but the surface of the resulting glaze layer is smooth.

In the method for manufacturing a thermal head of the present invention, crystallized glass paste is printed in two rows, and amorphous glass paste is further printed to cover these crystallized glass pastes. When this is fired, the two rows of crystallized glass paste do not lose their shape very much, and the two rows of crystallized glass paste [・
- becomes. Amorphous glass paste tends to flow during firing, but the crystallized glass glaze acts like a core, which not only suppresses that flow, but also because there are two rows of crystallized glass glaze side by side. The L portion of the glass glaze becomes substantially flat, and a glaze layer with a trapezoidal cross section is obtained as a whole.

If the cross-sectional shape of the glaze layer is trapezoidal, even if the glaze layer is formed with some deviation, the center of the heating resistor will still be located on the flat top of the glaze layer, and the efficiency of contact with the transfer ribbon etc. will be negligible. It does not change.

(F) Embodiment An example of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 (al indicates a crystallized glass space) 4'4' printed on an insulating substrate 2 made of alumina ceramic or the like using a silk screen. The crystallized glass paste 4'4' is printed in two parallel rows with a predetermined distance 1 apart. FIG. 1(1)) shows a state in which 5 degrees of amorphous glass paste was further printed using a silk screen. This amorphous glass paste 5° completely covers the crystallized glass paste 44′.

The printed glass ceramic substrate 2 with the crystallized glass paste 4'' and the amorphous glass paste 5'' is introduced into a furnace, and the glaze layer is fired. FIG. 1(C) shows the fired glaze layer 3. The crystallized glass paste 4' and 4' are respectively the crystallized glass glaze layer 4.
4, which almost retains the two-row form of paste printing. The amorphous glass paste 5'' becomes the amorphous glass glaze layer 5, but because of the two rows of crystallized glass glaze layers 4.4, its upper part is approximately flat. The fused glass glaze layer 4.4 and the amorphous glass glaze layer 5 constitute a glaze layer 3 having a substantially trapezoidal cross section. Although the boundary between the fused glass glaze layer 4.4 and the amorphous glass glaze layer 5 is shown by a line, in reality,
At the boundary, a complex state occurs where crystallized glass and amorphous glass react.

A heating resistor 6 is formed so as to straddle this glaze layer 3, and electrodes 7, 8 for making the heating resistor 6 thinner are formed.
is formed [see Fig. 2(,-1) and Fig. 3]. The heating resistor 6 and the electrodes 7.8 are formed using photolithography. Since the surface of the glaze layer 3 is composed of the smooth amorphous glass glaze layer 5, no problem occurs in forming the heating resistor 6.

In FIG. 2(a), the heating resistor 6 and the glaze layer 3 are in a predetermined positional relationship. For example, the center of the heating resistor 6 and the center of the glaze layer 3 are shown in a state where they are completely destroyed. but,
Since the positional accuracy of printing the crystallized glass paste 4° 4" and the amorphous glass paste 5° is not so high, as shown in FIG. 2(b), the center of the heating resistor 6 and the glaze layer 3
The center of the image may be misaligned. If this deviation is within a certain range, the part of the heating resistor 6 sandwiched between the electrodes 7 and 8 will still be located on the flat part of the glaze layer 3, and the efficiency of contact with the transfer ribbon etc. will be less. It does not change.

Note that an insulation protection layer is further formed on the insulating substrate 2, and the heating resistor 6 and the electrodes 7.8 are covered and protected.
This is omitted in FIGS. 2 and 3.

(g) Effects of the Invention In the method for manufacturing a thermal head of the present invention, when printing glass paste, crystallized glass paste is printed in at least two rows, and amorphous glass paste is further applied to cover these crystallized glass pastes. Special to print 1'l
! Therefore, the cross-sectional shape of the glaze layer formed by firing is approximately trapezoidal, and it is called a glaze layer.
Even if the positional relationship with the resistor is slightly shifted, the efficiency of contact with the transfer ribbon etc. does not change easily, and it has the advantage that variations in the contact efficiency of the seamal head can be reduced.

[Brief explanation of the drawing]

Fig. 1 (, -13, Fig. 1 (b3 and Fig. 1 (cl) C, C (7) Fig.・〕
) and FIG. 2(b) are sectional views of main parts of the thermal head in the same embodiment with heating resistors and electrodes formed, respectively, and FIG. 3 is a sectional view of FIG. 2(a). The main part plan views of the thermal head shown in FIGS. 4(a) and 4(b) are as follows:
FIG. 3 is a sectional view of a main part of a conventional thermal head. 2; Honshiro Jl (4 pieces, 3: Glaze layer, 4
: Crystallized glass glaze layer, 4゛: Crystallized glass space I., 5: Amorphous glass glaze layer, 5° Bi-amorphous glass paste, 6: Heat generating resistor, 7 and 8: Electrode. Figure 1 (a) ¥191i ROHM Co., Ltd. agent
Shigeru Nakamura 1. <Figure 1 (C) Figure (a) Figure

Claims (1)

[Claims] (1) Print glass paste on an insulating substrate, heat this insulating substrate and bake the glass paste into a glaze layer,
In the method for manufacturing a thermal head, in which an electrode for energizing the heating resistor is formed so as to span over the glaze layer, and the heating resistor row is further formed on the insulating substrate, when printing the glass paste, A method for manufacturing a thermal head, comprising printing crystallized glass paste in at least two rows, and further printing an amorphous glass paste to cover the crystallized glass paste.