JPH06144964A - Line type glazed substrate and production thereof - Google Patents

Abstract

PURPOSE:To provide a line type glazed substrate provided with a line glazed part low in heat conduction and excellent in linearity. CONSTITUTION:A line glazed part 11 having a prescribed thickness is formed by printing on the surface of an alumina substrate 10 by using a glazing paste consisting of a glazing material thermal expansion coefficient of which is -15% to 0% of that of the alumina substrate. The line type glazed substrate provided with the line glazed part having >=120mum glazing thickness and having circular- arc shaped cross section of 3-60mm radius of curvature in the width direction of the glazed part is obtained by firing the printed alumina substrate to make the width of the line glazed part larger than the width after printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line type glaze substrate provided with a linear glaze portion (hereinafter referred to as a line glaze portion), and more particularly to a page print type line in which head top linearity is required. The present invention relates to a line-type glaze substrate which is suitable for a thermal print head such as a type thermal head and a low power consumption or battery-powered portable thermal printer and a facsimile which are excellent in heat storage.

[0002]

2. Description of the Related Art Conventionally, this type of line-type glaze substrate is mainly used in page printers and the like, and in order to perform highly accurate printing, a glaze shape having a width of 1 mm or less and a thickness of 60 μm or less is adopted. (Japanese Patent Laid-Open No. 59-1569)
79). As the line-type glaze substrate, for example, as shown in Japanese Patent Laid-Open No. 4-46035, a BaO—SiO ₂ —Al ₂ O ₃ —CaO—B ₂ O ₃ -based glaze with low thermal conductivity is used. There is one used.

[0003]

By the way, in order to use the above-mentioned conventional line-type glaze substrate for a battery-driven facsimile, etc., the thickness of the line glaze portion is increased to further reduce the heat conduction and to improve the heat storage property. Need to improve. However, if it is attempted to further increase the thickness of the line glaze portion of the conventional line type glaze substrate, the rising angle of the glaze portion with respect to the substrate at the end of the line glaze portion becomes too large, and the conductor wiring formed in that portion is disconnected. There is a high possibility that a conduction failure such as a short circuit will occur. Further, if the width of the line glaze portion is made too wide, the glaze cross section does not have a single bow shape, and the linearity of the line glaze portion deteriorates. Furthermore, when the low thermal conductivity glaze of the above composition system is used, the coefficient of thermal expansion of the line glaze portion increases, causing a problem that a crack is generated between the substrate and the substrate due to a difference in thermal expansion. The present invention is intended to solve the above problems, and an object of the present invention is to provide a line-type glaze substrate having a line glaze portion having low thermal conductivity and good linearity.

[0004]

To achieve the above object, the structural feature of the invention according to claim 1 resides in that a line glaze portion having a glaze thickness of 120 μm or more is provided on a ceramic substrate.

Further, the structural feature of the invention according to claim 2 is that in the line-type glaze substrate according to claim 1, the cross-sectional shape of the line glaze portion in the width direction has an average curvature radius of 3 to 60 mm. There is a single bow shape in the range. If the average radius of curvature is 3 mm or less, the rising angle of the glaze portion with respect to the substrate at the end of the line glaze portion becomes too large, and there is a high possibility that the conductor wiring formed in that portion will have a conduction failure such as a disconnection or a short circuit. become. Further, if the average radius of curvature is 60 mm or more, the glaze cross section cannot be formed into a single bow shape. The average radius of curvature is controlled by the wettability of the ceramic substrate used, glaze composition, glaze printing conditions (paste viscosity, printing thickness, printing width), firing conditions (heating rate, holding temperature, holding time, cooling). It can be carried out by appropriately selecting conditions from each condition such as speed). Further, the average radius of curvature R is obtained by the following mathematical expression 1.

[0006]

## EQU1 ## R = (4t ² + w ² ) / 8t

However, t is the glaze thickness and w is the glaze width.

Further, the structural feature of the invention according to claim 3 is that in the line-type glaze substrate according to claim 1 or 2, the coefficient of thermal expansion of the material of the line glaze portion (from room temperature to 400 °). (Up to C) is within the range of -15% to 0% of the coefficient of thermal expansion of the ceramic substrate.

Further, the structural feature of the invention according to claim 4 is that the line glaze portion formed by printing in the method for producing a line glaze substrate according to claim 1, claim 2 or claim 3 The purpose is to increase the widthwise dimension by firing.

[0010]

In the invention according to claim 1 configured as described above, the line glaze portion has a glaze thickness of 120 μm or more, thereby lowering the heat conduction of the line glaze portion and enhancing the heat storage property. Is now possible. As a result, by forming the resistor of the thermal print head in this line glaze part, conduction of heat generated by the resistor to the ceramic substrate side can be suppressed and heat can be effectively used for printing. It is possible to provide a thermal print head capable of printing with low power consumption. Therefore, this line-type glaze substrate is preferably used for a thermal print head of a low power consumption or battery driven type facsimile.

Further, in the invention according to claim 2 configured as described above, by setting the average radius of curvature of the cross section in the width direction of the line glaze portion in the range of 3 to 60 mm, the glaze thickness is 120 μm or more and the width is It became possible to make the cross-sectional shape of the direction a single bow shape, which also improved the linearity of the glaze. Also, by defining the average radius of curvature in the above range, even though the glaze thickness is increased, the rising edge of the line glaze portion with respect to the substrate becomes smooth, so There is no possibility that the formed conductor wiring will be defective in conduction such as disconnection or short circuit.

Further, in the invention according to claim 3 configured as described above, the thermal expansion coefficient of the glaze material (from room temperature to 400 ° C) is -15% to 0% of the thermal expansion coefficient of the ceramic substrate. By setting the range, it is possible to prevent the warp of the line-type glaze substrate which may be caused by making the glaze thickness as thick as 120 μm or more.

Further, in the invention according to claim 4 configured as described above, unlike the prior art, the dimension in the width direction of the line glaze portion is made wider than the dimension in the width direction of the print line glaze portion before firing. By forming, 1
It was possible to form a line glaze portion having a glaze thickness of 20 μm or more and a single bow-shaped cross section.

[0014]

EXAMPLE An example of the present invention will be specifically described below. First, the plane size is 280 mm x 80 mm, and the thickness is 0.6.
35 mm alumina substrate (96% alumina content) 10
To prepare. SiO ₂ = 50.5, Al ₂ O ₃ = 6.9, B ₂ O ₃ = 2.7, MgO = 0.3, C on the surface of this alumina substrate 10 in terms of oxide equivalent weight%.
Using a glaze paste for printing in which a glass powder having a composition of aO = 3.8, SrO = 26.8, BaO = 8.9 was mixed with an ethylcellulose-based organic binder, as shown in FIG. A line glaze portion (hereinafter, referred to as a glaze portion) 11 was printed so as to have a thickness of 200 μm based on the thickness multiplication of the partial glaze, to obtain a test product. The glaze composition has a thermal expansion coefficient of 7.2 × 10 ⁻⁶ / ° C, and a thermal expansion coefficient of 7.8 to 8.0 × 10 ⁻⁶ / ° C of a normal alumina substrate. The difference in expansion is about -9% (from room temperature to 400 ° C), and there is no problem with respect to acid resistance. As a reference, a comparative product having a width of 2 mm and a glaze portion having a thickness of 60 μm after firing was prepared by printing. Next,
This test product and the comparison product, alumina substrate 10, were
By firing at 0 ° C. for about 2 hours, line-type glaze substrates of test products and comparative products were obtained.

The glaze substrate of the test product had a thickness of the glaze portion 11 of 150 μm and a width of 2.5 mm, and the average radius of curvature was about 6.6 mm. The cross-sectional shape of the glaze portion 11 in the width direction is a single bow shape as shown in FIG.
The linearity of 1 was also good. Further, the warp of the glaze substrate was also equal to that of the conventional product. Further, the comparative glaze substrate had a thickness of 60 μm and a width of 2 mm, and the cross-sectional shape of the glaze portion 12 in the width direction had ridges formed at both ends, as schematically shown in FIG. Thus, it became clear that when the glaze thickness is thin, the glaze portion does not spread in the width direction and the cross section does not have a single bow shape.

As described above, in this embodiment, the glaze portion is formed by printing on the alumina substrate so that the thickness after firing is 120 μm or more, and the glass after firing is fired by melting the glass during firing. By making the dimension in the width direction larger than the dimension in the width direction of the glaze portion after printing, a single bow-shaped glaze having a thickness of 120 μm or more and a cross-sectional shape in the width direction having an average curvature radius of 3 to 60 mm. A line type glaze substrate having a portion could be obtained. For this reason, this line-type glaze substrate has low thermal conductivity in the glaze portion and good linearity. Also,
By defining the average radius of curvature in the above range, even though the glaze thickness is increased, the rise of the glaze portion at the end portion of the line glaze portion with respect to the substrate becomes smooth, so it is formed at the end portion of the line glaze portion. There is also no possibility of a conductive failure such as disconnection or short circuit in the conductor wiring. Further, by setting the thermal expansion coefficient of the glaze material of this substrate within the range of −15% to 0% (from room temperature to 400 ° C.) of the thermal expansion coefficient of the alumina substrate, the substrate by the glaze portion which is significantly thicker than the conventional one Can be prevented from warping.

By forming the resistor of the thermal print head in the glaze portion of the line-type glaze substrate having such characteristics, conduction of heat generation by the resistor to the alumina substrate side is suppressed, and heat generation is effective for printing. Since it can be utilized, it is possible to provide a thermal print head capable of printing with lower power consumption than before. Therefore, the line type glaze substrate,
It is preferably used for thermal print heads of low power consumption or battery driven type facsimiles.

Although the line type glaze substrate using the alumina substrate has been described in the above embodiments, the present invention may be applied to an aluminum nitride substrate or the like.

[Brief description of drawings]

FIG. 1 is a plan view of a line-type glaze substrate according to an embodiment of the present invention.

FIG. 2 is a schematic view showing a cross section in the width direction (thickness: 150 μm, width: 2.5 mm) of a glaze portion of the same line-type glaze substrate.

FIG. 3 is a schematic view showing a cross section in the width direction (having a thickness of 60 μm and a width of 2 mm) of a glaze portion of a line-type glaze substrate of a comparative product.

[Explanation of symbols]

 10; Alumina substrate, 11, 12; Glaze part.

Claims (4)

[Claims] 1. A glaze thickness 12 on a ceramic substrate.
A line-type glaze substrate having a line glaze portion of 0 μm or more. 2. The line-type glaze substrate according to claim 1, wherein the cross-sectional shape of the line glaze portion in the width direction is a single bow shape having an average radius of curvature in the range of 3 to 60 mm. Line type glaze board. 3. The line-type glaze substrate according to claim 1 or 2, wherein the coefficient of thermal expansion (from room temperature to 400 ° C.) of the material of the line-glaze portion is equal to the coefficient of thermal expansion of the ceramic substrate. A line-type glaze substrate having a range of 15% to 0%. 4. The claim 1, claim 2, or claim 3.
The method for manufacturing a line-type glaze substrate according to the item 1, wherein the dimension of the printed line-glaze portion in the width direction is increased by firing.