JP5317831B2 - Thermal head and thermal printer equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal head capable of slide-contacting satisfactorily with a recording medium, and a thermal printer equipped therewith. <P>SOLUTION: This thermal head 10 includes a head substrate 20 having end faces 20a extended along main scanning directions D1, D2, and a plurality of heating parts 40a arrayed along the main scanning directions D1, D2 on the end faces 20a of the head substrate 20, the head substrate 20 has chamfering faces 20a<SB>1</SB>in both ends of the end faces 20a in the main scanning directions D1, D2, and a cross angle &theta; between the chamfering face 20a<SB>1</SB>and the end face 20a is brought into 6&deg; or more to 19&deg; or less. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a thermal head including a substrate and heating elements arranged on an end surface of the substrate, and a thermal printer including the thermal head.

  An example of a printing apparatus that employs a thermal recording method is a thermal printer for plastic cards. In this thermal printer, a thermal head having a head substrate, a plurality of heating elements arranged on the head substrate, and a protective layer covering the plurality of heating elements, a plastic card serving as a recording medium toward the heating elements, and A transport mechanism that transports the ink film containing the ink component while pressing the protective film against the protective layer on the heating element. In the thermal printer having such a configuration, the plastic card and the ink film are conveyed while being pressed almost uniformly on the protective layer on the heating element of the thermal head, and the ink component of the ink film melted or sublimated by the heat of the heating element is made into plastic. A desired image is printed by transferring to the card.

However, in the above thermal printer, in transferring the ink component ink film to a plastic card, it pressed against the ink film at the corner portion of the head substrate of the thermal head, will occur wrinkles in Lee ink film, this ink film The wrinkle pattern may be printed as an image. In view of this, a thermal head has been developed in which a chamfered portion is provided at the corner of the head substrate and the recording medium is most strongly pressed to the center of the chamfered surface in the main scanning direction to reduce wrinkles. Yes.

JP 2005-7826 A

  However, in a thermal printer that employs an end face type thermal head in which a heating element is provided on the end face of the head substrate, the heating element is provided on the end face that is in sliding contact with the recording medium. Therefore, in such a thermal printer, when the recording medium is most strongly pressed against the center of the end surface, the pressing force of the recording medium varies, and density unevenness due to the variation of the pressing force occurs. There is a case.

  The present invention has been conceived under such circumstances, and an object thereof is to provide a thermal head capable of satisfactorily contacting a recording medium and a thermal printer including the same. .

The thermal head of the present invention includes a substrate having an end surface extending along the main scanning direction, a plurality of heating elements arranged along the main scanning direction on the end surface of the substrate, and the end surface of the substrate. And a heat storage layer provided between the plurality of heat generating elements, a plurality of heat generating elements, and a covering layer covering a part of the heat storage layer, and the substrate has a surface which is chamfered at both ends in the main scanning direction, Ri 19 ° der less angle of intersection 6 ° or more and the chamfered to face the end surface, the heat storage layer was the chamfered surface It has the site | part exposed from the said coating layer, and the surface roughness of the said exposed site | part is small compared with the surface roughness of the said coating layer, It is characterized by the above-mentioned.

  In the thermal head of the present invention, it is preferable that an intersection angle between the chamfered surface and the end surface is 6 ° or more and 15 ° or less.

Also, the exposure in the thermal head, a portion exposed from the coating layer, in the main scanning direction has become wider in the sub-scanning direction toward outward from said end face, and from the covering layer It is preferable that the length in the main scanning direction is the longest in a portion adjacent to the row of the plurality of heat generating elements among the portions that are arranged .

  The thermal printer of the present invention includes the thermal head of the present invention and a transport mechanism that presses the recording medium against the end face and the chamfered surface side of the thermal head and transports the recording medium in the sub-scanning direction. It is characterized by.

The thermal head of the present invention includes a substrate having an end surface extending along the main scanning direction, a plurality of heating elements arranged along the main scanning direction on the end surface of the substrate, and the end surface of the substrate. And a heat storage layer provided between the plurality of heat generating elements, a plurality of heat generating elements, and a covering layer covering a part of the heat storage layer, and the substrate has a surface which is chamfered at both ends in the main scanning direction, Ri 19 ° der less angle of intersection 6 ° or more and the chamfered to face the end surface, the heat storage layer was the chamfered surface The surface roughness of the exposed portion is smaller than the surface roughness of the coating layer. Therefore, with the thermal of the present invention, even when the recording medium is pressed against the boundary between the chamfered surface and the end surface, the pressing force applied to the recording medium can be dispersed. Therefore, in the thermal head of the present invention, the recording medium can be satisfactorily brought into sliding contact. Further, this thermal head can relatively increase the dynamic friction force applied to the recording medium at the central portion where the heating elements are arranged, as compared with the both end portions where the chamfered surfaces are provided. For this reason, in this thermal head, by concentrating the area where the dynamic friction force applied to the recording medium acts on the central part, for example, the conveyance area of the recording medium due to the difference of the dynamic friction force at the both ends of the area where the dynamic friction force acts is reduced. can do
.

  In the thermal head of the present invention, when the crossing angle between the chamfered surface and the end surface is 6 ° or more and 15 ° or less, even when the recording medium is pressed against the boundary portion between the chamfered surface and the end surface, the recording medium Can be dispersed well, and the recording medium can be slidably contacted.

Further, in this thermal head, the portion exposed from the coating layer has a width in the sub-scanning direction that increases outward from the end face in the main scanning direction, and is exposed from the coating layer. When the length in the main scanning direction is the longest in the portion adjacent to the row of the plurality of heating elements among the portions that are, the case where the recording medium is pressed against the boundary between the chamfered surface and the end surface In addition, the recording medium can be satisfactorily slidably contacted in a region adjacent to the row of the plurality of heating elements having the largest pressing force.

  The thermal printer of the present invention includes the thermal head of the present invention. Therefore, the thermal printer of the present invention can enjoy the effects of the thermal head of the present invention. Therefore, in the thermal printer of the present invention, the recording medium can be satisfactorily slid and the recording medium can be transported satisfactorily.

1 is a perspective view illustrating a schematic configuration in which a protective layer is omitted as an example of an embodiment of a thermal head of the present invention. It is the front view which expanded the principal part of the thermal head shown in FIG. FIG. 2 is an enlarged plan view of a main part of the thermal head shown in FIG. 1. FIG. 2 is an enlarged side view of a main part of the thermal head shown in FIG. 1. It is sectional drawing along the VV line shown in FIG. 1 is a schematic configuration diagram illustrating an example of an embodiment of a thermal printer of the present invention. Is a plan view showing a reference example of service Maruheddo.

<Thermal head>
The thermal head 10 which is an example of the embodiment of the thermal head of the present invention shown in FIGS. 1 to 5 includes a head substrate 20, a heat storage layer 30, an electric resistance layer 40, a conductive layer 50, a protective layer 60, The drive IC 70 is included.

  The head substrate 20 has a function of supporting the heat storage layer 30, the electrical resistance layer 40, the conductive layer 50, the protective layer 60, and the drive IC 70. As a material for forming the head substrate 20, for example, an insulating resin including ceramics, glass, or epoxy resin can be used.

  The head substrate 20 has an end surface 20a extending in the main scanning directions D1 and D2 on the D5 direction side of the main surface extending directions D5 and D6. The end surface 20a of the head substrate 20 is configured in a rectangular shape having a longer length in the main scanning directions D1 and D2 than a length in the sub-scanning directions D3 and D4 in plan view. Here, the “plan view” means a view in the D6 direction in the main surface extending directions D5 and D6. The length of the end surface 20a of the head substrate 20 in the main scanning directions D1 and D2 is appropriately set according to the size of the recording medium to be printed. The length of the end surface 20a of the head substrate 20 in the sub-scanning directions D3 and D4 is, for example, in the range of 1.5 mm to 3.5 mm.

  The heat storage layer 30 has a function of temporarily storing a part of heat generated in a heat generating portion 40a described later of the electric resistance layer 40. That is, the heat storage layer 30 plays a role of improving the thermal response characteristics of the thermal head 10 by shortening the time required to raise the temperature of the heat generating portion 40a. The heat storage layer 30 is located on the end surface 20a of the head substrate 20, and is configured in a strip shape extending in the main scanning directions D1 and D2. Further, in the heat storage layer 30, the upper surface 30a on the D5 direction side in the main surface extending directions D5 and D6 is formed in a substantially semi-elliptical shape in a cross section along the sub-scanning directions D3 and D4. Examples of the curvature of the upper surface 30a of the heat storage layer 30 include a range of R1.15 or more and R1.50 or less at a portion where the heat generating portion 40a is provided. Moreover, as thickness along the main surface extension direction D5, D6 of this thermal storage layer 30, the range of 55 micrometers or more and 95 micrometers or less is mentioned in the thickest part, for example.

  The electrical resistance layer 40 includes a heat generating portion 40a that functions as a heat generating element that generates heat when power is supplied. The electrical resistance layer 40 is configured such that the electrical resistance value per unit length is larger than the electrical resistance value per unit length of the conductive layer 50. Examples of the material for forming the electric resistance layer 40 include a TaN-based material, a TaSiO-based material, a TaSiNO-based material, a TiSiCO-based material, and an NbSiO-based material. Here, the “material mainly comprising” means that the principal material is 50% by mass or more based on the whole, and may contain, for example, an additive. Such an electric resistance layer 40 can be formed by various well-known manufacturing methods using, for example, vapor deposition, CVD, sputtering, photolithography, or printing. The electric resistance layer 40 of this example is formed of a TaSiO-based material. Examples of the thickness along the principal surface extending directions D5 and D6 of the electric resistance layer 40 include a range of 20 nm to 80 nm. A part of the electric resistance layer 40 is provided on the heat storage layer 30 and the other is provided on the main surface of the head substrate 20. Moreover, in the electrical resistance layer 40 of this example, the site | part in which the conductive layer 50 is not formed among the site | parts provided on the thermal storage layer 30 functions as the heat generating part 40a.

  The heat generating part 40a is a part that functions as a heat generating element that generates heat by power supply. The heat generating portion 40a is configured such that the heat generation temperature due to power supply from the conductive layer 50 is in the range of 200 ° C. or higher and 550 ° C. or lower, for example. The heat generating portions 40a are located in the heat storage layer 30 and are arranged at substantially the same separation distance along the main scanning directions D1 and D2. In addition, each of the heat generating portions 40a is configured in a rectangular shape in plan view. Furthermore, the heat generating part 40a is configured to have substantially the same length along the main scanning directions D1 and D2. Further, the heat generating portion 40a is configured to have substantially the same length along the sub-scanning directions D3 and D4. Here, “substantially the same” includes those within a general manufacturing error range, for example, a range in which an error with respect to the average value of the length of each part is within 10%. Here, examples of the value of the separation distance between the center of one heat generating portion 40a and the center of another heat generating portion 40a adjacent to the heat generating portion 40a include a range of 5.2 μm or more and 84.7 μm or less.

  The conductive layer 50 has a function of applying a voltage to the heat generating part 40a provided on the electric resistance layer 40 as a wiring pattern. A part of the conductive layer 50 is provided on a part of the electric resistance layer 40 provided on the heat storage layer 30, and the other is provided on the main surface of the head substrate 20. Examples of the thickness along the principal surface extending directions D5 and D6 of the conductive layer 50 include a range of 500 nm to 800 nm. As a material for forming the conductive layer 50, for example, any one of aluminum, gold, silver, and copper, or an alloy thereof can be used. Such a conductive layer 50 can be formed by various well-known manufacturing methods using, for example, vapor deposition, CVD, sputtering, photolithography, or printing. The conductive layer 50 includes a first conductive layer 51 and a second conductive layer 52.

  The first conductive layer 51 functions as a control wiring together with the electric resistance layer 40 located on the D6 direction side in the main surface extending directions D5 and D6. The first conductive layer 51 contributes to supplying power to the heat generating portion 40a. The first conductive layer 51 has one end portion electrically connected to each heat generating portion 40 a and the other end portion electrically connected to the control IC 70.

  The end of the second conductive layer 52 is electrically connected to the other end of the plurality of heat generating portions 40a. The second conductive layer 52 contributes to supplying power to the heat generating portion 40a in pairs with the first conductive layer 51. The second conductive layer 52 of this example is electrically connected to a reference voltage source as a power source.

The protective layer 60 has a function of protecting the heat generating portion 40 a and the conductive layer 50. The protective layer 60 is formed so as to cover the heat generating portion 40a and a part of the conductive layer 50 along the main scanning directions D1 and D2. Examples of the material for forming the protective layer 60 include diamond-like carbon materials, SiC materials, SiN materials, SiCN materials, SiAlON materials, SiO ₂ materials, and TaO materials. Here, “diamond-like carbon-based material” refers to a material in which the proportion of carbon atoms (C atoms) taking sp ³ hybrid orbitals is in the range of 1 atomic% or more and less than 100 atomic%. Examples of the thickness of the protective layer 60 include a range of 5 μm to 12 μm. Examples of the curvature of the upper surface 60a of the protective layer 60 include a range of R1.15 or more and R1.50 or less at a portion covering the heat generating portion 40a.

Head substrate 20 of the present embodiment, both end portions in the main scanning direction D1, D2 of the end face 20a are chamfered, and has a chamfered surface 20a _1. Further, the heat storage layer 30 of the present embodiment, both end portions in the main scanning direction D1, D2 are chamfered, and has a chamfered surface 30a _1. Further, the protective layer 60 of the present embodiment, both end portions in the main scanning direction D1, D2 are chamfered, and has a chamfered surface 60a _1. The chamfered surface 20a ₁ of the head substrate 20, the chamfered surface 30a ₁ of the heat storage layer 30, the chamfered surface 60a ₁ of the protective layer 60 constitutes the same chamfered surface 10a _1. The chamfered surface 10a ₁ is provided as a plane. Such chamfer 10a ₁ can be formed by chamfering for example, a heat storage layer 30 and the protective layer 60 on the head substrate 20 having on the end face 20a _1. Such chamfering can be processed by, for example, mechanical polishing, chemical polishing, or the like. That is, the chamfered surface 20a ₁ of the head substrate 20 of the present embodiment, the chamfered surface 30a ₁ of the heat storage layer 30, is exposed from the protective layer 60.

Further, the chamfered surface 20a ₁ of the head substrate 20, the chamfered surface 30a ₁ of the heat storage layer 30, the chamfered surface 60a ₁ of the protective layer 60 constitutes the same chamfered surface 10a, and the chamfered surface 10a ₁ head The intersection angle θ with the end surface 20a of the substrate 20 is set to be 6 ° or more and 19 ° or less. Here, the “intersection angle” means that when the head substrate 20 is viewed in the D3 direction in the sub-scanning directions D3 and D4, the end of the end surface 20a of the head substrate 20 extends at the end on the D5 direction side in the thickness directions D5 and D6. a virtual line, refers to an angle intersecting with the chamfered surface 20a _1. That means the angle at which the main scanning direction D1, D2 and the chamfered surface 20a ₁ intersect.

Further, the chamfered surface 30a ₁ of the heat storage layer 30 is most widely width _{W G} in the main scanning direction D1, D2 in the region in a row and column of the plurality of heat generating portions 40a, the width _{W G} is the sub-scanning direction D3, In D4, the distance from the row of the plurality of heat generating portions 40a becomes narrower. That is, the chamfered surface 30a ₁ of the heat storage layer 30 is exposed most in the area that protrudes D5 direction of the main surface extending direction D5, D6. Further, the chamfered surface 30a ₁ of the heat storage layer 30, the width _{L G} in the sub-scanning direction D3, D4 toward the end surface 20a to the both ends is wider in the main scanning direction D1, D2.

Furthermore, the chamfered surface 30 a ₁ of the heat storage layer 30 is provided so that the surface roughness is smaller than the surface roughness of the upper surface 60 a of the protective layer 60. Such a chamfered surface 30a ₁ can be provided by forming the chamfered surface 30a ₁ by polishing.

  The drive IC 70 has a function of controlling the power supply state of the plurality of heat generating units 40a. The drive IC 70 is electrically connected to the other end portion of the first conductive layer 51. With this configuration, the heat generating portion 40a can be selectively heated.

The thermal head 10 has a head substrate 20 having an end surface 20a extending along the main scanning directions D1 and D2, and a plurality of thermal heads 10 arranged on the end surface 20a of the head substrate 20 along the main scanning directions D1 and D2. and a heat generating portion 40a, the head substrate 20 has a chamfered surface 20a ₁ at both ends of the end surface 20a in the main scanning direction D1, D2, the intersection angle θ between the chamfered surface 20a ₁ and the end face 20a It is 6 ° or more and 19 ° or less. Therefore, in the thermal head 10, even when pressed against a recording medium at the boundary between the chamfered surface 20a ₁ and the end face 20a, it is possible to disperse the pressure applied to the recording medium. Therefore, in the thermal head 10, the recording medium can be brought into good sliding contact.

The thermal head 10 includes a heat storage layer 30 provided between the end surface 20a of the head substrate 20 and the plurality of heat generating portions 40a, and a coating layer that covers the plurality of heat generating portions 40a and a part of the heat storage layer 30. has a protective layer 60, the heat storage layer 30 is adjacent to the chamfered surface 20a _1, has a portion exposed from the protective layer 60, the chamfered surface 30a is a portion which is the exposed since the _first surface roughness is smaller than the surface roughness of the top surface 60a of the protection layer 60, the recording medium in the central portion which is arranged in the heat generating portion 40a than at both ends provided with chamfers 20a ₁ The applied dynamic friction force can be relatively increased. For this reason, in the thermal head 10, by concentrating the region where the dynamic friction force applied to the recording medium acts on the central portion, for example, the region where the dynamic friction force acts is different in the dynamic friction force at both ends, thereby causing variations in conveyance of the recording medium. Can be reduced. Therefore, the thermal head 10 can transport the recording medium satisfactorily.

In the thermal head 10, portions exposed from the protective layer 60 of the heat storage layer 30 is wider width L _G in the sub-scanning direction D3, D4 toward the both end sides from the end surface 20a in the main scanning direction D1, D2 and the length W _G in the main scanning direction D1, D2 adjacent the columns of heating elements 40a is the longest, when pressed against the recording medium at the boundary between the chamfered surface 20a ₁ and the end face 20a The recording medium can be satisfactorily slidably contacted in the region aligned with the row of the plurality of heat generating portions 40a having the largest pressing force.
<Thermal printer>
The thermal printer 1 as an example of the embodiment of the thermal printer of the present invention shown in FIG. 6 has a thermal head 10, a transport mechanism 11, and a control mechanism 12.

  The transport mechanism 11 transports the recording paper P and the ink film F as recording media in the D3 direction in the sub-scanning directions D3 and D4, while the recording paper P is placed on the protective layer 60 positioned on the heat generating portion 40a of the thermal head 10. It has a function of contacting through the ink film F. The transport mechanism 11 includes a platen roller 111 and transport rollers 112, 113, 114, and 115.

The platen roller 111 has a function of pressing the recording medium against the protective layer 60 located on the heat generating portion 40a. The platen roller 111 is rotatably supported in contact with the protective layer 60 located on the heat generating portion 40a. Further, the platen roller 111 is rotatably supported in contact to the chamfered surface 10a _1. The platen roller 111 of this example has a configuration in which the outer surface of a columnar base is covered with an elastic member. The base is made of, for example, a metal such as stainless steel, and the elastic member is made of, for example, butadiene rubber having a thickness dimension in the range of 3 mm to 15 mm. That is, in the thermal printer 1 of the present embodiment, the recording medium is brought into sliding contact with the thermal head 10 by the elastic pressure of the elastic member that constitutes the platen roller. At this time, the recording medium, so that the sliding contact with the upper surface 60a of the protection layer 60 of the thermal head 10, on the chamfered surface 10a _1.

  The transport rollers 112, 113, 114, and 115 have a function of transporting the recording medium. That is, the transport rollers 112, 113, 114, and 115 supply a recording medium between the heat generating part 40 a of the thermal head 10 and the platen roller 111, and from between the heat generating part 40 a of the thermal head 10 and the platen roller 111. It plays the role of pulling out the recording medium. These transport rollers 112, 113, 114, and 115 may be formed of, for example, a metal columnar member. For example, like the platen roller 111, the outer surface of the columnar substrate is covered with an elastic member. There may be.

  The control mechanism 12 has a function of supplying image information to the drive IC 70. That is, the control mechanism 12 plays a role of supplying image information for selectively driving the heat generating portion 40 a to the drive IC 70.

  The thermal printer 1 includes a thermal head 10. Therefore, the thermal printer 1 can enjoy the effects of the thermal head 10. Therefore, in the thermal printer 1, the ink film F and the thermal head 10 can be conveyed in good sliding contact.

  While specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications can be made without departing from the scope of the invention.

  The heat generating portions 40a of this example are each connected to the independent first conductive layer 51, but are not limited to such a configuration. For example, different heat generating portions 40 a and heat generating portions 40 a may be connected to one independent first conductive layer 51.

  Here, the effect of the thermal head of the present invention was confirmed by experiments.

  First, thermal head A without a chamfered surface and thermal heads B to I with a chamfered surface were prepared. These thermal heads B to I differ only in the intersection angle θ between the end surface of the head substrate and the chamfered surface. The crossing angle θ in each of the thermal heads B to I is such that B is 4 degrees, C is 6 degrees, D is 10 degrees, E is 12 degrees, and F is 15 degrees, G is 19 degrees, H is 27 degrees, and I is 47 degrees.

-Schematic structure of thermal heads A to I-
-Head substrate forming material: Alumina ceramics-Head substrate length in main scanning direction: 65.05 mm
-Length (thickness) in the sub-scanning direction of the head substrate: 2 mm
-Curvature of the end surface of the head substrate: R1.35 ± 0.15
-Heat storage layer forming material: SiO-based material-Heat storage layer thickness: 75 ± 15 μm
-Curvature of end face of heat storage layer: R1.30 ± 0.15
・ Material for forming protective layer: SiC-based material ・ Thickness of protective layer: 6 μm
-Curvature of protective layer: R1.30 ± 0.15
Next, each of the thermal heads A to I is mounted on a thermal printer A (manufactured by Kyocera Corporation, an experimental machine), and an ink film (an ink film adopted as a standard of the label printer SR424 manufactured by SATO) is slid onto each thermal head as a recording medium. The recording medium was transported while being in contact with the recording medium.

-Thermal printer A-
-Diameter of platen roller: 19 mm
・ Thickness of elastic part of platen roller: 4 mm
・ Length of platen roller in main scanning direction: 66 mm
・ Platen roller hardness: 65 °
・ Pressing pressure of the platen roller: 0.5 × 10 ⁶ Pa per one
-Conveying conditions-
-Conveying speed of recording medium: 100 mm / s
Table 1 shows the experimental results of this conveyance experiment. In Table 1, “イ ン ク” indicates that the ink film was not wrinkled, and “◯” indicates that the ink film was wrinkled but had no practical problem. Those with wrinkles are evaluated as “Δ”.

  From the above results, it is understood that the recording medium can be slidably brought into practical use by employing the thermal heads C to G in which the crossing angle θ between the end surface of the head substrate and the chamfered surface is 6 degrees or more and 19 degrees or less. It was.

  In addition, from the above results, it is possible to make the recording medium more slidable by adopting the thermal heads C to F in which the intersection angle θ between the end surface of the head substrate and the chamfered surface is 6 degrees or more and 15 degrees or less. I understood.

1 Thermal Printer 10 Thermal Head 10a Chamfered Surface 11 Transport Mechanism 111 Platen Rollers 112, 113, 114, 115 Transport Roller 12 Drive Mechanism 20 Head Substrate (Substrate)
20a End face 20a _One chamfered surface 30 Heat storage layer 30a Upper surface 30a _One chamfered surface 40 Electrical resistance layer 40a Heat generating part (heat generating element)
50 conductive layer 51 first conductive layer 52 second conductive layer 60 protective layer 60a upper surface 60a ₁ chamfered surface 70 control IC
θ Crossing angle F between the end surface of the head substrate and the chamfered surface F Ink film P Recording medium

Claims (4)

A substrate having an end surface extending along a main scanning direction;
A plurality of heating elements arranged along the main scanning direction on the end face of the substrate;
A heat storage layer provided between the end face of the substrate and the plurality of heating elements;
A plurality of heating elements, and a covering layer covering a part of the heat storage layer ,
The substrate has chamfered surfaces at both ends in the main scanning direction of the end surface;
Intersection angle between the end face and chamfered been face 6 ° or 19 ° Ri der below,
The heat storage layer is adjacent to the chamfered surface and has a portion exposed from the coating layer, and the surface roughness of the exposed portion is compared to the surface roughness of the coating layer. And small thermal head.   The thermal head according to claim 1, wherein an angle of intersection between the chamfered surface and the end surface is 6 ° or more and 15 ° or less. The portions exposed from the coating layer have a width in the sub-scanning direction that increases outward from the end surface in the main scanning direction, and the plurality of portions exposed from the coating layer 3. The thermal head according to claim 2 , wherein a length in the main scanning direction is longest at a portion adjacent to the row of heating elements . The thermal head according to any one of claims 1 to 3 ,
A thermal printer, comprising: a transport mechanism that presses the recording medium toward the end face side and the chamfered surface side of the thermal head and transports the recording medium in a sub-scanning direction.

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