Novel heating substrate for thermal printing head
By setting a dense transition layer below the silver public electrode with the thermist -sensitive head and setting a micro -tooth array on it, the problem of penetration of the silver public electrode and the substrate glass glaze layer is solved. Effect of adhesion.
Patent Information
- Application Number
- CN202421416901.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-20
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-06-20
AI Technical Summary
The silver common electrode of the conventional thermal print head is prone to permeate with the glass glaze layer of the substrate during the sintering process, resulting in poor shape, increased linear resistance, and reduced adhesion between the electrode and the substrate.
There is a dense transition layer below the silver public electrode. The dense transition layer adopts a conductive layer structure formed by sintering. The area is greater than the area of the silver public electrode. The micro -tooth array is set on the transition layer to improve the binding force.
Effectively prevent the silver public electrode from penetrating with the substrate glass glaze layer during the sintering process, reduce the line resistance, improve the adhesion of the electrode and the substrate, and enhance the reliability and quality of the product.
Smart Images
Figure CN222407701U_ABST
Abstract
Description
Technical field:
[0001] The utility model relates to the technical field of thermal print head manufacturing, and specifically to a new type of heating substrate for thermal print heads, which can improve the quality of the silver common electrode in the thermal print head product, reduce its line resistance, and improve its bonding strength with the bottom glaze layer without damaging the bottom glaze. Background technology:
[0002] In the field of thermal printing, a thermal print head has a full bottom glaze layer on the heating substrate, which is formed by chemical etching or mechanical grinding, and a local raised structure is formed on the full bottom glaze layer to facilitate contact with the printing medium. In the prior art, a first glaze layer with a raised structure can also be formed locally on the heating substrate by screen printing, and a full glaze layer is set in the area outside the first glaze layer and connected to the first glaze layer. However, the material softening point of the full glaze layer set by the above technical means must be much lower than the first glaze layer, otherwise the first glaze layer will be deformed due to heat in the subsequent preparation process of the full glaze layer. The manufacture of thermal print heads also includes forming a silver common electrode by screen printing and sintering on the full glaze layer. In order to reduce the line resistance of the silver common electrode, powdered or sheet-shaped silver paste is generally used to form a silver common electrode of more than 10μm. The powdered silver paste used has a high porosity, and in the process of forming the silver common electrode, the sintering temperature of the silver paste must be lower than the softening point of the full glaze layer, otherwise it will cause the full glaze layer to flow, and further the full glaze layer will penetrate the silver electrode, resulting in poor shape and increased line resistance of the silver electrode. Under the existing product structure and process conditions, if the sintering temperature of the silver common electrode is reduced, the adhesion between the silver common electrode and the substrate will be greatly reduced, and the powdered silver paste sintered at low temperature has a very loose and porous structure and is not dense, resulting in an increase in the resistivity of the formed silver electrode. Summary of the invention:
[0003] In view of the shortcomings and deficiencies in the prior art, the utility model proposes a novel heating substrate for a thermal print head which has a reasonable structure and is easy to operate and can effectively improve the quality of the silver common electrode without significantly increasing the production cost.
[0004] The utility model achieves this through the following measures:
[0005] A novel heating substrate for a thermal print head is provided with an insulating substrate, a base glaze layer is provided on the insulating substrate, a heating resistor and an electrode wire are provided on the upper surface of the base glaze layer, wherein the electrode wire includes a common electrode, an individual electrode and a common electrode, and the common electrode includes an X-direction segment arranged parallel to the heating resistor. It is characterized in that a dense transition layer is also provided between the common electrode and the base glaze layer, and the area of the dense transition layer is larger than the area of the common electrode.
[0006] The bottom glaze layer of the utility model adopts a glass glaze layer whose sintering temperature is higher than the sintering temperature of the dense transition layer and the common electrode.
[0007] The thickness of the dense transition layer of the utility model ranges from 0.5 to 2 μm, and adopts a magnetron sputtering silicon oxide layer, a magnetron sputtering silicon nitride layer, a magnetron sputtering silicon carbide layer, a magnetron sputtering silver layer, an organic silver sintered layer, an organic gold sintered layer, or a magnetron sputtering silver layer.
[0008] The upper surface of the dense transition layer of the utility model is provided with a micro-tooth array to improve the surface roughness and ensure the bonding force between the common electrode and the dense transition layer; further, the upper surface of the bottom glaze layer corresponding to the dense transition layer is provided with a micro-tooth array to improve the bonding force between the bottom glaze layer and the dense transition layer.
[0009] The common electrode of the utility model also includes two common electrode segments in the Y direction which are respectively connected to the two ends of the X direction segment vertically. The common electrode is arranged along the outer sides of the heating resistor, the individual electrode and the common electrode.
[0010] The utility model discloses an insulating substrate having an upper surface provided with a first glaze layer along the length direction of the heating resistor, the first glaze layer having an arched surface, a second glaze layer corresponding to the common electrode setting area on the upper surface of the insulating substrate, the second glaze layer having a thickness less than the first glaze layer and a flat surface, the first glaze layer and the second glaze layer being glass glaze layers with a softening point in the range of 850-1000°C, a silver common electrode being provided on the second glaze layer, a dense transition layer being provided between the second glaze layer and the silver common electrode, a heating resistor being provided on the first glaze layer, and also a common electrode and individual electrodes being provided, the heating resistor being arranged between the common electrode and the individual electrodes; further, a third glaze layer is provided on the insulating substrate, the third glaze layer covering the area outside the first glaze layer and the second glaze layer, the common electrode and individual electrodes made of aluminum being provided on the upper surfaces of the third glaze layer and the first glaze layer, the insulating substrate, the heating resistor and the local wire electrode being covered with a first insulating protective layer and a second wear-resistant protective layer.
[0011] The utility model further provides a solder resist coating in the blank area between the solder pad and the glaze layer, and the thickness of the solder resist layer is set in the range of 5μm-25μm.
[0012] In the utility model, the width of the first glaze layer is set in the range of 0.3mm-2.0mm, the thickness of the first glaze layer is set in the range of 20μm-100μm, the thickness of the second glaze layer or the third glaze layer is set in the range of 3μm-10μm, and further, the third glaze layer is used to cover the area on the surface of the insulating substrate where the first glaze layer and the second glaze layer are not set, and the overlapping width of the third glaze layer and the first glaze layer and the second glaze layer is set in the range of 50μm-150μm.
[0013] The total thickness of the protective layer in the utility model is set in the range of 3μm-10μm.
[0014] When the utility model is working, since a dense transition layer is added on the upper side of the high softening point glass glaze layer below the silver common electrode, especially when the dense transition layer adopts a conductive layer structure formed by sintering, the bottom of the dense transition layer and the high softening point glass mutually penetrate during the sintering process, which can enhance the adhesion with the substrate. However, since the dense transition layer is not penetrated in subsequent processing, the problem of mutual penetration between the silver common electrode and the bottom glass glaze layer due to high sintering during preparation can be effectively prevented, thereby achieving the purpose of reducing the line resistance of the silver electrode and improving product reliability and quality. Description of the drawings:
[0015] Figure 1 It is a structural schematic diagram of the utility model.
[0016] Figure 2 It is a schematic diagram of the structure of the silver common electrode arrangement area in the utility model.
[0017] Figure 3 It is a schematic diagram of the glaze layer arrangement structure of the utility model.
[0018] Figure 4 It is a schematic diagram of the plane structure of the utility model.
[0019] Figure numerals: 10 - insulating substrate, 20 - first glaze layer, 30 - second glaze layer, 40 - dense transition layer, 50 - silver common electrode, 60 - third glaze layer, 70 - heating resistor, 80a - common electrode, 80b - individual electrode, 90 - first protective layer, 100 - second protective layer, 110 - solder resist coating. Specific implementation method:
[0020] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings.
[0021] Embodiment 1:
[0022] like Figure 1 As shown, this example proposes a novel heating substrate for a thermal print head, wherein an underglaze layer is provided on an insulating substrate, a heating resistor 70 and an electrode wire are provided on the upper surface of the underglaze layer, wherein the electrode wire comprises a common electrode 80a, an individual electrode 80b and a common electrode 50, wherein the common electrode 50 comprises an X-direction segment arranged parallel to the heating resistor, and a dense transition layer 40 is further provided between the common electrode 50 and the underglaze layer, wherein the area of the dense transition layer 40 is larger than the area of the common electrode 50;
[0023] The bottom glaze layer of this example adopts a glass glaze layer with a sintering temperature higher than that of the dense transition layer 40 and the common electrode. Specifically, the bottom glaze layer of this example is formed by partially printing an amorphous bottom glaze slurry on the insulating substrate 10 and sintering it at a temperature of 1200-1250° C. The bottom glaze layer includes: a first glaze layer 20 distributed along the long side direction of the insulating substrate 10, the width of the first glaze layer 20 is set in the range of 0.3mm-2.0mm, and the thickness is set in the range of 20μm-100μm, and a second glaze layer 30 is further provided, the setting area of the second glaze layer 30 overlaps with the setting area of the silver common electrode 50, and the area of the second glaze layer 30 is larger than the area of the common electrode 50, and the thickness of the second glaze layer 30 is set in the range of 3μm-10μm;
[0024] Printing glass glaze slurry on the insulating substrate 10 on one side of the first glaze layer 20 along the short side direction (Y direction) of the insulating substrate 10, sintering at a temperature of 750-850° C. to form a third glaze layer 60 partially overlapping the first glaze layer 20 and the second glaze layer, with the overlapping width being set within a range of 50 μm-100 μm;
[0025] On the second glaze layer, screen-printed organic silver paste or organic gold paste is used, and sintered at a temperature of 750-850° C. to form a dense transition layer 40, the thickness of which is 0.5-2 μm, wherein the organic silver sintered layer or the organic gold sintered layer refers to a dense transition layer formed by sintering an organic silver paste or an organic gold paste, wherein the organic gold paste or the organic silver paste can be a mature product available on the market, such as the organic gold paste or the organic silver paste provided by manufacturers such as Xi'an Hongxing Electronic Paste Technology Co., Ltd.;
[0026] Further, a powdered silver paste layer for preparing a silver common electrode 50 is provided on the dense transition layer 40 by screen printing, and sintered at a temperature of 750-850° C. to form the silver common electrode 50, with a thickness of 10-20 μm;
[0027] A plurality of heating resistors 70 are provided on the first glaze layer 20. The heating resistors 70 are arranged along the main printing direction (i.e., the long side direction of the insulating substrate 10). The heating resistors 70 are formed on the first glaze layer 20 by sputtering coating and photoengraving technology. In this example, the heating resistors 70 can be formed of tantalum silicon oxide or tantalum nitride. Sputtering coating and photoengraving technology are used to form wire electrodes 80 on the first glaze layer 20 and the second glaze layer 30. The wire electrodes 80 include a common electrode 80a and an individual electrode 80b. The heating resistors 70 are arranged Between the common electrode and the individual electrode, a first protective layer 90 and a second protective layer 100 are formed by sputtering coating on the outside of the insulating substrate 10, the first glaze layer 20, the second glaze layer 30, the third glaze layer 60, the silver common electrode 50, the heating resistor 70 and the wire electrode 80. The protective layer at least covers the insulating substrate 10, the heating resistor 70 and the partial wire electrode 80. The total thickness of the two protective layers is set at 3-10 μm. A solder resist coating 110 is set on a part of the protective layer. The thickness of the solder resist is set at 5-25 μm.
[0028] The beneficial effect of this example is that the above-mentioned new type of heating substrate for thermal print head can enhance the adhesion between silver and the substrate by arranging a high melting point second glaze layer on the paper outlet side of the first glaze layer, arranging a dense transition layer 40 thereon, and printing and sintering the silver common electrode 50 on the dense layer, and preventing the mutual penetration of silver and glass at high sintering temperature. The dense transition layer used can reduce the line resistance of the silver electrode, and the performance and reliability of the above-mentioned new type of heating substrate for thermal print head can be improved.
[0029] Embodiment 2:
[0030] Benli provides a novel heating substrate for a thermal print head, which is provided with an insulating substrate 10, on which an underglaze layer is provided, and a heating resistor 70 and an electrode wire are provided on the upper surface of the underglaze layer, wherein the electrode wire includes a common electrode 80a, an individual electrode 80b and a common electrode 50, and the common electrode 50 includes an X-direction segment provided in parallel with the heating resistor 70, and a dense transition layer 40 is provided between the common electrode 50 and the underglaze layer, and the area of the dense transition layer is larger than the area of the common electrode; the underglaze layer is a glass glaze layer having a sintering temperature higher than the sintering temperature of the dense transition layer 40 and the common electrode 50; in this example, the dense transition layer 40 has a thickness range of 0.5-2 μm, and adopts a magnetron sputtering silicon oxide layer, or a magnetron sputtering silicon nitride layer;
[0031] In this example, the upper surface of the dense transition layer 40 is provided with a micro-tooth array to improve the surface roughness and ensure the bonding force between the common electrode 50 and the dense transition layer 40; the upper surface of the bottom glaze layer corresponding to the dense transition layer 40 is provided with a micro-tooth array to improve the bonding force between the bottom glaze layer and the dense transition layer 40;
[0032] The common electrode 50 in this example also includes two common electrode segments in the Y direction that are perpendicularly connected to the two ends of the X direction segment. The common electrode 50 is arranged along the outer sides of the heating resistor 70, the individual electrode 80b, and the common electrode 80a.
[0033] In this example, the upper surface of the insulating substrate is provided with a first glaze layer 20 along the length direction of the heating resistor 70, and the first glaze layer 20 has an arched surface. The upper surface of the insulating substrate is provided with a second glaze layer 30 corresponding to the common electrode setting area. The second glaze layer 30 is thinner than the first glaze layer 20 and has a flat surface. The first glaze layer 20 and the second glaze layer 30 are both glass glaze layers with a softening point range of 850-1000°C. A silver common electrode 50 is provided on the second glaze layer 30, and a dense transition layer 40 is provided between the second glaze layer 30 and the silver common electrode 50. A heating resistor 70 is provided on a glaze layer 20, and a common electrode 80a and an individual electrode 80b are also provided. The heating resistor 70 is arranged between the common electrode and the individual electrode; further, a third glaze layer 60 is provided on the insulating substrate, and the third glaze layer 60 covers the area outside the first glaze layer 20 and the second glaze layer 30. The common electrode and the individual electrode made of aluminum are arranged on the upper surface of the third glaze layer 60 and the first glaze layer, and the insulating substrate, the heating resistor 70 and the local wire electrode are covered with a first insulating protective layer and a second wear-resistant protective layer.
[0034] In this example, a solder resist coating is provided in the blank area between the pad and the glaze layer, and the thickness of the solder resist layer is set in the range of 5 μm-25 μm; in this example, the total thickness of the protective layer is set in the range of 3 μm-10 μm.
[0035] When this example is working, a dense transition layer is added on the upper side of the high softening point glass glaze layer below the silver common electrode. The dense transition layer adopts an insulating silicon oxide layer or silicon nitride layer formed by sputtering, thereby avoiding the problem of mutual penetration between the silver common electrode and the underlying glass glaze layer due to high-temperature sintering during preparation. In order to improve the bonding force between the layer structures, a micro-tooth array is also provided between the dense transition layer and the silver common electrode, and between the dense transition layer and the bottom glaze layer. Compared with the prior art, this example can enhance the adhesion between the silver common electrode and the substrate and achieve the purpose of improving product reliability and quality.
Claims
1. A novel heating substrate for a thermal print head, comprising an insulating substrate, an underglaze layer on the insulating substrate, a heating resistor and an electrode lead arranged on the upper surface of the underglaze layer, wherein the electrode lead comprises a common electrode, an individual electrode and a common electrode, and the common electrode comprises an X-direction segment arranged parallel to the heating resistor, characterized in that: A dense transition layer is also provided between the common electrode and the bottom glaze layer, and the area of the dense transition layer is larger than the area of the common electrode.
2. A novel heating substrate for a thermal print head according to claim 1, characterized in that: The bottom glaze layer is a glass glaze layer whose sintering temperature is higher than the sintering temperature of the dense transition layer and the common electrode.
3. A novel heating substrate for a thermal print head according to claim 1, characterized in that: The thickness of the dense transition layer is in the range of 0.5-2 μm, and is a magnetron sputtered silicon oxide layer, a magnetron sputtered silicon nitride layer, a magnetron sputtered silicon carbide layer, a magnetron sputtered silver layer, an organic silver sintered layer, or an organic gold sintered layer.
4. A novel heating substrate for a thermal print head according to claim 1, characterized in that: The upper surface of the density transition layer is provided with a micro-tooth array to improve the surface roughness and ensure the bonding force between the common electrode and the density transition layer.
5. A novel heating substrate for a thermal print head according to claim 4, characterized in that: A micro-tooth array is provided on the upper surface of the bottom glaze layer corresponding to the density transition layer to improve the bonding force between the bottom glaze layer and the density transition layer.
6. A novel heating substrate for a thermal print head according to claim 1, characterized in that: The common electrode also includes two common electrode segments in the Y direction which are respectively connected to the two ends of the X direction segment vertically. The common electrode is arranged along the outer sides of the heating resistor, the individual electrode and the common electrode.
7. A novel heating substrate for a thermal print head according to claim 1, characterized in that: A first glaze layer is provided on the upper surface of the insulating substrate along the length direction of the heating resistor, and the first glaze layer has an arched surface. A second glaze layer is provided on the upper surface of the insulating substrate corresponding to the common electrode setting area. The second glaze layer is thinner than the first glaze layer and has a flat surface. Both the first glaze layer and the second glaze layer are glass glaze layers with a softening point range of 850-1000°C. A silver common electrode is provided on the second glaze layer, and a dense transition layer is provided between the second glaze layer and the silver common electrode. A heating resistor is provided on the first glaze layer, and a common electrode and individual electrodes are also provided. The heating resistor is arranged between the common electrode and the individual electrode.
8. The novel heating substrate for a thermal print head according to claim 7, characterized in that: A third glaze layer is also provided on the insulating substrate, and the third glaze layer covers the area outside the first glaze layer and the second glaze layer. Common electrodes and individual electrodes made of aluminum are arranged on the upper surfaces of the third glaze layer and the first glaze layer. The insulating substrate, the heating resistor and the local wire electrode are covered with a first insulating protective layer and a second wear-resistant protective layer.
9. The novel heating substrate for a thermal print head according to claim 1, characterized in that: A solder resist coating is provided in a blank area between the pad and the glaze layer, and the thickness of the solder resist layer is set within a range of 5 μm-25 μm.
10. The novel heating substrate for a thermal print head according to claim 8, characterized in that: The width of the first glaze layer is set in the range of 0.3mm-2.0mm, the thickness of the first glaze layer is set in the range of 20μm-100μm, the thickness of the second glaze layer or the third glaze layer is set in the range of 3μm-10μm, the third glaze layer is used to cover the area on the surface of the insulating substrate where the first glaze layer and the second glaze layer are not set, and the overlapping width of the third glaze layer and the first glaze layer and the second glaze layer is set in the range of 50μm-150μm; the total thickness of the protective layer is set in the range of 3μm-10μm.