JPS5835369B2 - Method of manufacturing thermal substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a heat-sensitive substrate having an electrode body and a resistor that are bonded to each other.

A thermosensitive substrate has a lead electrode body and a resistor connected to the electrode body formed on a base body, and forms an image on thermal paper by heat generation when electricity is applied to the resistor through the electrode body.

Therefore, the resistor on this heat-sensitive substrate is formed as a thick film by screen printing together with the electrode body, but conventionally the resistor is formed in a planar shape across the electrode body, or the resistor is formed between the electrode bodies. , a manufacturing method is disclosed in which unnecessary portions are then removed by photoetching to form a resistor into a predetermined shape.

However, in a resistor formed as a thick film by screen printing, the outer peripheral edge is not straight due to the mesh of the screen, but has a non-linear shape such as a sawtooth shape, and is not formed with high precision.

For this reason, the bonding edge of the resistor that is superimposed and bonded to the electrode body also becomes non-linear, making it impossible to obtain an accurate shape.

However, the conventionally disclosed method of obtaining the shape of the resistor by photoetching is only for accurately obtaining the line width of the resistor, and it is not possible to accurately form the joining edge of the resistor with the electrode body in a straight line. It is not considered that the formation of

For this reason, the problem that the bonding edge of the resistor with the electrode body is non-linear and inaccurate remains unresolved, and therefore the resistance value changes due to the inaccuracy of the shape of the resistor. There is a problem in that the amount of heat generated by the resistor changes and the image on the thermal paper becomes unclear.

The present invention provides a method for manufacturing a heat-sensitive substrate that solves these problems.

The method for manufacturing a heat-sensitive substrate of the present invention includes forming an electrode body made of a thick film on a base, then forming a resistor made of a thick film on the base by joining the electrode body, and then forming a resistor made of a thick film on the base. This method is characterized in that the joint edges of the body are removed by photo-etching.

Therefore, in the method of manufacturing a heat-sensitive substrate of the present invention, when forming an electrode body and a resistor made of a thick film body and bonded to each other on a substrate by screen printing, the resistor is bonded to the electrode body by polymerization. The edges are removed by photo-etching to form straight lines. By using photo-etching with high molding accuracy, the non-linear joining edges of screen-printed resistors can be easily and precisely formed. This allows for linear removal.

With this manufacturing method, by combining the process of removing the other non-linear outer peripheral edges of the resistor by photoetching and forming the resistor in a straight line, the entire resistor can be formed into a precise shape with high precision. .

In the heat-sensitive substrate obtained by the manufacturing method of the present invention, in addition to the bonding portion between the electrode body and the resistor formed on the base, the bonding edge of the resistor that is polymerized and bonded onto the electrode body forms a straight line. Therefore, the joining edge of the resistor and its shape are highly precise and accurate, and therefore the resistance value of the resistor is constant and accurate.

Therefore, in the manufactured thermal substrate, the amount of heat generated by the resistor is constant, and a clear image can be formed on thermal paper.

As described above, according to the present invention, in addition to the shape accuracy that occurs at the joint portion of the resistor formed by screen printing,! =-
By using photoetching to solve the drawbacks of heat sensitive substrates, it is possible to improve the shape accuracy of the entire resistor including the bonding edges, maintain a constant and accurate amount of heat generated by the resistor, and improve the characteristics of the heat-sensitive substrate.

Next, a method for manufacturing a heat-sensitive substrate according to the present invention will be described.

As shown in FIG. 1, a plurality of electrode bodies 2 made of conductive paste are thickly formed on the main surface of a base 1 made of ceramic or glass by screen printing, and the formed electrode bodies 2 are fired.

In this case, the electrode bodies 2 are arranged, for example, in a pattern on both sides of the base 1 so as to face each other at parallel intervals.

Next, as shown in FIG. 2, a planar resistor layer 3 made of resistor paste is formed as a thick film by screen printing on the central part of the main surface of the base 1 so as to cross between each electrode body 2. The formed resistor layer 3 is fired.

Among them, both sides of the resistor layer 30 serve as bonding parts for each electrode body 2.
Polymerize and join onto the ends of the.

Next, a photoresist (photosensitive agent) is applied on the main surface of the substrate 1 including the planar resistor layer 3, and then a mask having a predetermined resistor shape is placed on the main surface of the substrate 1 and exposed to infrared rays. By performing further development using a developer, unnecessary portions of the resistor layer 3 are removed, and resistors 4 are formed individually between each electrode body 2 facing each other as shown in FIG. .

The resistor 4 has straight edges 4a on both sides in the longitudinal direction between each electrode body 2, and a joining edge 4b that overlaps and joins each electrode body 2.
Also assume that the shape is a straight line.

As shown in FIG. 5, during exposure, the mask is placed on the resistor layer 3 at both side edges 4a between each electrode body 2 and at the joint edge 4b.
is divided by a straight line and only the inside thereof is exposed to light, and then during development, the unnecessary resistor layer 3 portion A (present on the substrate 1) excluding the resistor 4 is removed via the straight side edges 4a. At the same time, the unnecessary resistor layer 3 portion B (existing on the electrode body 2) excluding the resistor 4 is removed via the bonding edge 4b to form the resistor 4.

To explain further, the resistor layer 3 is formed into a thick film by screen printing, and the outer peripheral edge 3a including the portion located on the electrode body 2 has a non-linear shape, but as described above, the bonding edge of the resistor 4 By forming the portion 4b in a straight line, the non-linear outer peripheral edge 3a is removed during development and a straight joining edge 4b is formed.

(Note that the joint edge 4b is located inside the outer peripheral edge 3a.

In addition, the outer peripheral edge 3a other than on the electrode body 2 is an unnecessary resistor layer 3.
will be removed together with.

) Moreover, by using photoetching, it is possible to form the joining edge 4b of the resistor 4 into a straight line with high accuracy.

As described above, the present invention is characterized in that both edges 4a of the resistor 40 are formed by photoetching, and at the same time, the joining edges 4b are formed straight.

Next, as shown in FIG. 4, an overcoat glass layer 5 is formed and covered by screen printing on the electrode body 2 button and the resistor body 4.

In the heat-sensitive substrate thus obtained, not only the resistor 40 and both measuring parts 4a but also the bonding edge 4b form a straight line, so a highly accurate shape can be obtained, and the resistance value is accurate and there is no variation. Therefore, the amount of heat generated by the resistor remains constant, making it possible to form a clear image on thermal paper.

In the method for manufacturing a heat-sensitive substrate of the present invention, the conductive paste for forming the electrode body is, for example, Au paste, which is applied to a thickness of, for example, 5 to 20 μm, and heated at, for example, 800 to 900°C. Bake at a temperature of

The insulating paste for forming the resistor is, for example, RuO.
2 paste, etc., is applied to a thickness of, for example, 30 to 80 μm, and baked at a temperature of, for example, 800 to 900°C.

The photoresist used in photoetching includes diazotized polyvinyl alcohol, acroyl compound, etc., and the developer used includes water, trichlorethylene, tetracool ethylene, etc.

Additionally, the electrode body and the resistor may be formed not only directly on the base, but also on a base layer formed on the base.

[Brief explanation of drawings]

Claims (1)

[Claims] 1. An electrode body made of a thick film is formed on a base, and then a resistor made of a thick film is formed on the base by joining with the electrode body, and then the bonded edge of this resistor is photoetched. A method for producing a heat-sensitive substrate, the method comprising removing the heat-sensitive substrate.