Scratch-proof thermal printing head

Abstract

The utility model relates to the technical field of thermal printing head manufacturing, in particular to a scratch-proof thermal printing head which is reasonable in structure, low in cost and capable of remarkably reducing scratches to a printing medium in the printing process so as to improve the printing quality, and is characterized in that a glass glaze layer is further arranged on the upper surface of an insulating substrate; the glass glaze layer is arranged on the paper outlet side of the heating resistor body, the distance between the center of the glass glaze layer and the center of the heating resistor body is not smaller than 1.0 mm, the width ranges from 0.2 mm to 1.2 mm, the thickness ranges from 10 micrometers to 70 micrometers, the glass glaze layer is in a strip shape and is parallel to the heating resistor body, and the electrode wire part is located above the glass glaze layer. The device has the remarkable advantages of reasonable structure, low cost, simplicity and convenience in operation and the like.

Description

Technical field:

[0001] The utility model relates to the technical field of thermal print head manufacturing, in particular to an anti-scratch thermal print head which has a reasonable structure and low cost and can significantly reduce scratches on a print medium during printing, thereby improving the printing quality. Background technology:

[0002] The thermal print head structure commonly used in the prior art is as follows: Figure 1 As shown, it includes a heat sink 1, on which an insulating substrate 2 and a circuit board 3 are arranged, on the surface of the insulating substrate 2 at least a portion of which is provided with a heat storage layer 4, on the surface of at least the heat storage layer 4 a heating resistor 5 is arranged, on both sides of the heating resistor 5 electrodes 6 are arranged, and on the surfaces of the heating resistor 5 and part of the electrodes 6 a protective layer 7 is covered. The upper corner of the insulating substrate 2 of the above structure is generally a right angle, such as Figure 2 As shown, when the printer is working, the print roller rotates and the print medium 9 moves along the secondary scanning direction. At the same time, the print roller is elastically deformed due to the pressure, pressing the print medium 9 toward the thermal print head, thereby contacting the upper corner of the insulating substrate 2, which will cause scratches on the print medium 9 and damage the text or image on the print medium 9, affecting the printing quality; and if the printer is provided with a paper return function, this structure will also be accompanied by the occurrence of printing paper jam problems.

[0003] In order to prevent the printing medium from being scratched, the following related solutions are proposed in the prior art: the patent with publication number CN217293997U, entitled a scratch-resistant heating substrate for a thermal print head, discloses that the heat storage layer is arranged on a chamfered surface with a certain angle to the upper surface along the length direction of the insulating substrate, and the gap to the edge of the insulating substrate in the main scanning direction is not less than 0.1mm. This structure can effectively prevent the sharp tip of the substrate edge from scratching the printing medium due to cutting. This technical solution has high process difficulty.

[0004] The patent with publication number JP5425511B2, titled Thermal Print Head and Manufacturing Method thereof, discloses that a first blade with a sharp tip is used to grind and chamfer the end of an insulating plate on the downstream side of the printing medium conveying direction, and after the chamfering step, a second blade with a flat tip is used to perform end surface processing on the chamfered portion of the insulating plate. This structure can prevent damage to the end of the printing medium of the thermal print head on the downstream side of the conveying direction.

[0005] The above-mentioned related documents all design chamfers for the insulating substrate of the thermal print head to prevent the printing medium from being scratched. However, in the above-mentioned method, the edge of the insulating substrate needs to be processed multiple times, which makes the processing complicated and increases the production cost. Summary of the invention:

[0006] In view of the shortcomings and deficiencies in the prior art, the utility model proposes an anti-scratch thermal print head which has a reasonable structure and is easy to operate and can significantly reduce scratches on printing media without increasing production costs.

[0007] The utility model achieves this through the following measures:

[0008] A scratch-resistant thermal print head is provided with an insulating substrate, a heat storage layer is provided on the insulating substrate, a heating resistor and an electrode wire are provided on the heat storage layer, and a protective layer is provided above the heating resistor and part of the electrode wire. The invention is characterized in that a glass glaze layer is also provided on the upper surface of the insulating substrate, the glass glaze layer is arranged on the paper outlet side of the heating resistor, the center of the glass glaze layer is not less than 1.0 mm from the center of the heating resistor, the width range is 0.2-1.2 mm, and the thickness range is 10-70 μm. The glass glaze layer is strip-shaped and arranged parallel to the heating resistor, and the electrode wire portion is located above the glass glaze layer.

[0009] The edge of the glass glaze layer of the utility model is not less than 0.01mm away from the edge of the insulating substrate. Furthermore, the cross-section of the glass glaze layer is triangular or a trapezoid that is narrow at the top and wide at the bottom, and a protective layer is directly provided above the glass glaze layer, or a protective layer is provided after a portion of the wire electrode is provided on the upper surface of the glass glaze layer. The protective layer smoothly hangs down along the top of the glass glaze layer and covers the edge of the paper outlet side of the insulating substrate, forming a downward inclined surface with a slope located at the edge of the paper outlet side of the insulating substrate, thereby effectively lifting the printing medium hanging on the edge of the paper outlet side of the insulating substrate during the printing process, so that after the printing medium contacts with the top of the glass glaze layer, the probability of contact with the edge of the paper outlet side of the insulating substrate is reduced, so as to overcome the problem of the existing printing medium being scratched by the sharp edge of the insulating substrate.

[0010] The glass glaze layer described in the utility model is a continuous strip arranged parallel to the heating resistor, or a strip arranged intermittently, and the gap range between adjacent intermittent strip glass glaze layers is not less than 0.2mm, so as to ensure stable product quality and reduce production costs. At the same time, it can avoid the formation of irregular horn protrusions at both ends of the strip glaze layer due to too small a gap, thereby affecting the quality of printed text or images.

[0011] The protective layer of the utility model is an insulating protective layer, a wear-resistant layer, a corrosion-resistant layer or an organic resin layer, or a stack of several of them.

[0012] Compared with the prior art, the utility model forms a strip glass glaze layer structure at the paper outlet side of the flat insulating substrate surface, thereby eliminating the need for repeatedly grinding the edge of the insulating substrate to form a smooth chamfer in the traditional process, or eliminating the complicated chamfer surface film forming operation in the traditional process. It can reduce the probability of contact between the printing medium on the paper outlet side and the sharp edge of the insulating substrate without affecting the normal printing, thereby improving the printing quality, and has the significant advantages of reasonable structure, low cost, and easy operation. Description of the drawings:

[0013] Attached Figure 1 It is a schematic diagram of the side structure of a thermal print head in the prior art.

[0014] Attached Figure 2 It is a schematic diagram of the printing state of a thermal print head in the prior art.

[0015] Attached Figure 3 It is a schematic diagram of the side structure of the thermal print head of the utility model.

[0016] Attached Figure 4 It is a schematic diagram of the printing state of the thermal print head of the utility model.

[0017] Attached Figure 5 It is a front schematic diagram of a continuous strip glass glaze layer on an insulating substrate in an implementation case of the utility model.

[0018] Attached Figure 6 It is a front view schematic diagram of a strip glass glaze layer intermittently arranged on an insulating substrate in an implementation case of the utility model.

[0019] Reference numerals: heat sink 1 , insulating substrate 2 , circuit board 3 , heat storage layer 4 , heating resistor 5 , electrode 6 , protective layer 7 , glass glaze layer 8 . Specific implementation method:

[0020] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] Example:

[0022] This example provides a scratch-resistant thermal print head, such as Figure 3 As shown, it includes a heat sink 1, on which an insulating substrate 2 and a circuit board 3 are provided, on at least a part of the surface of the insulating substrate 2, a heat storage layer 4 is formed by screen printing and sintering, and a glass glaze layer 8 is provided at the upper end near the insulating substrate 2, and the formation of the glass glaze layer 8 can be completed simultaneously with the heat storage layer 4; a heating resistor 5 and an electrode 6 are provided at least on the upper surface of the heat storage layer 4 and the glass glaze layer 8, and a protective layer 7 is provided on the surface of the heating resistor 5 and part of the electrode 6, and the protective layer 7 generally includes an insulating protective layer, a wear-resistant layer, a corrosion-resistant layer, an organic resin layer, etc.;

[0023] In this example, a glass glaze layer 8 is added along the main scanning direction near the upper end of the insulating substrate 2. The glass glaze layer 8 is continuous or has a plurality of intervals of long strips, such as the attached Figure 5 or attached Figure 6 As shown, the glass glaze layer 8 has a width of 0.2-1.2 mm and a thickness of 10-70 μm, and a distance from the upper end and the left and right ends of the insulating substrate 2 of ≥ 0.01 mm.

[0024] Compared with the prior art, the thermal print head involved in this example is as follows Figure 4 As shown, during the printing process, the raised structure of the glass glaze layer 8 can keep the printing medium 9 away from the upper corner of the insulating substrate 2, preventing the sharp tip there from scratching the printing medium 9, thereby ensuring high printing quality.

[0025] Compared with the prior art, this example has significant advantages such as reasonable structure, low cost, and easy operation.

Claims

1. A scratch-resistant thermal print head, comprising an insulating substrate, a heat storage layer on the insulating substrate, a heating resistor and an electrode lead on the heat storage layer, and a protective layer above the heating resistor and part of the electrode lead, characterized in that: A glass glaze layer is also provided on the upper surface of the insulating substrate, and the glass glaze layer is arranged on the paper outlet side of the heating resistor. The center of the glass glaze layer is not less than 1.0 mm from the center of the heating resistor, the width range is 0.2-1.2 mm, and the thickness range is 10-70 μm. The glass glaze layer is strip-shaped and arranged parallel to the heating resistor, and the electrode wire portion is located above the glass glaze layer.

2. The scratch-resistant thermal print head according to claim 1, characterized in that: The edge of the glass glaze layer is not less than 0.01 mm away from the edge of the insulating substrate.

3. The scratch-resistant thermal print head according to claim 2, characterized in that: The cross-section of the glass glaze layer is triangular or a trapezoid that is narrow at the top and wide at the bottom, and a protective layer is directly provided on the glass glaze layer, or a protective layer is provided after a partial wire electrode is provided on the upper surface of the glass glaze layer. The protective layer smoothly hangs down along the top of the glass glaze layer and covers the edge of the paper outlet side of the insulating substrate, forming a downward inclined surface with a slope located at the edge of the paper outlet side of the insulating substrate.

4. The scratch-resistant thermal print head according to claim 1, characterized in that: The glass glaze layer is in the form of a continuous strip arranged parallel to the heating resistor, or in the form of a discontinuous strip, and the gap between adjacent discontinuous strips of the glass glaze layer is not less than 0.2 mm.

5. The scratch-resistant thermal print head according to claim 1, characterized in that: The protective layer is an insulating protective layer, a wear-resistant layer, a corrosion-resistant layer or an organic resin layer, or a stack of several of them.

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