JP2010194856A - Recording head and recording apparatus equipped with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording head high in reliability, and a recording apparatus. <P>SOLUTION: A thermal head 10 includes a head base body 20 which has heating parts 23a arranged along main scan directions D1 and D2, drive ICs 26, and conductive layers 24 connected with the heating parts or the drive ICs and prepared at both sides of each drive IC; and a wiring base body 30 which has a first wiring substrate, a second wiring substrate 32, and a wiring layer 33 set between the first and second wiring substrates and connected with the conductive layers. The second wiring substrate has a main extension 321 which extends along an end of the heating part side of the first wiring substrate, and a projecting part 322 which projects from the end of the first wiring substrate to the heating part side. The projecting part has an end of the heating part side along the main scan directions D1 and D2. The wiring layer has a first extension and a second extension which extend to the projecting part. The first extension and the second extension are connected with the conductive layers along the main scan directions D1 and D2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a recording head and a recording apparatus including a head substrate having a plurality of heat generating portions, and a wiring substrate electrically connected to the head substrate to energize the plurality of heat generating portions. About.

  As a printer such as a facsimile or a register, a thermal printer including a thermal head and a platen roller is used. As a thermal head mounted on such a thermal printer, a head base having a plurality of heat generating portions arranged on a substrate surface, and a mechanical structure along the main scanning direction with respect to the head base. And a wiring substrate that is electrically connected to a plurality of heat generating portions. The platen roller has a function of pressing a recording medium such as thermal paper against the heat generating portion. In the thermal printer having such a configuration, the heat generating portion generates heat according to a desired image, and the recording medium is pressed evenly on the heat generating portion with a platen roller, thereby generating heat generated by the heat generating portion with respect to the recording medium. Good transmission. Desired printing on the recording medium is performed by repeating this process.

  Some of the thermal heads as described above have a head base and a wiring base that are mechanically and electrically connected in the main scanning direction. In such a thermal head, thermal expansion occurs when the heat generating portion generates heat.

JP-A-6-262790

In such a thermal head, thermal expansion occurs when the heat generating portion generates heat. At the time of this thermal expansion, since the thermal expansion coefficients of the head substrate and the wiring substrate are different, the thermal stress resulting from this thermal expansion is concentrated at the end in the main scanning direction. As a result, when the thermal head is repeatedly driven and the heat cycle of heat generation and heat dissipation is repeated, the wiring substrate may be peeled off from the head substrate. In particular, the peeling between the wiring substrate and the head substrate is likely to occur significantly when the difference in thermal expansion coefficient between the wiring substrate and the head substrate becomes large or the conductive material in the wiring substrate becomes thin.

  The present invention has been conceived under such circumstances, and an object of the present invention is to provide a recording head having high reliability against heat and a recording apparatus including the recording head.

  The recording head of the present invention includes a head substrate, a plurality of heating elements arranged along the main scanning direction on the head substrate, and the plurality of heating elements arranged along the main scanning direction. A plurality of driving elements for controlling driving; and a plurality of conductive layers provided on both sides in the main scanning direction of each of the plurality of driving elements connected to the plurality of heating elements or the plurality of driving elements; A head base, a first support substrate, a second support substrate provided to overlap the first support substrate, and the first support substrate and the second support substrate. A wiring base having a plurality of wirings connected to the plurality of conductive layers, and the second support substrate extends along the end of the first support substrate. And the heating element of the first support substrate A plurality of projecting portions projecting toward the heat generating element in the sub-scanning direction from the end on the side, and the plurality of projecting portions are arranged such that the end on the heat generating element side in the sub-scanning direction is the main scanning. The plurality of wirings have a plurality of extending portions extending to the plurality of projecting portions, and the plurality of extending portions are formed on the plurality of conductive layers in the main scanning. It is connected along the direction.

  In the recording head according to the aspect of the invention, it is preferable that the ends of the plurality of conductive layers on the wiring substrate side extend along the main scanning direction.

  In the recording head according to the aspect of the invention, it is preferable that the plurality of projecting portions have a narrower width along the main scanning direction as projecting toward the heating element.

  In the recording head according to the aspect of the invention, the plurality of wirings include a first wiring pattern, and the first wiring pattern is an end on the heat generating element side in the main extending portion and the protruding portion of the second support substrate. It is preferable that it is provided along. In the recording head, it is preferable that the plurality of wirings include a second wiring pattern, and the second wiring pattern is provided with an end on the heating element side along the first wiring pattern. .

  In the recording head of the present invention, the head substrate has a protective layer that covers a part of the plurality of conductive layers, and the protective layer has an end on the wiring substrate side that is the heat generation of the second support substrate. It is preferable to extend along the end on the element side.

  In the recording head according to the aspect of the invention, the plurality of wirings may have a smaller connection area to the plurality of conductive layers at both ends of the plurality of driving elements in the main scanning direction than between the plurality of driving elements. preferable.

  A recording apparatus of the present invention includes the recording head of the present invention and a transport unit that transports a recording medium.

  The recording head of the present invention drives a head substrate, a plurality of heating elements arranged on the head substrate along the main scanning direction, and a plurality of heating elements arranged along the main scanning direction. A plurality of drive elements to be controlled, and a plurality of heat generating elements or a plurality of conductive layers provided on both sides in the main scanning direction of each of the plurality of drive elements connected to the plurality of drive elements. A plurality of conductive layers provided between the first support substrate and the second support substrate; a head base; a first support substrate; a second support substrate provided to overlap the first support substrate; A wiring base having a plurality of connected wirings, the second support substrate having a main extension extending along an end of the first support substrate on the side of the heating element, and a first support Projecting from the edge of the substrate toward the heating element in the sub-scanning direction A plurality of protrusions, and the plurality of protrusions have heat generating element side ends in the sub-scanning direction along the main scanning direction, and the plurality of wirings extend to the plurality of protrusions. The plurality of extending portions are connected to the plurality of conductive layers along the main scanning direction. Therefore, in the recording head of the present invention, it is possible to reduce the occurrence of variations in the thermal stress applied to the wiring substrate between the end of the second support substrate on the heating element side and the wiring. Therefore, in this recording head, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

  In the recording head of the present invention, when the plurality of conductive layers extend along the main scanning direction at the end of the wiring substrate side, the heat stress between the end of the second support substrate on the side of the heating element and the protruding portion is increased. Variations can be reduced. Therefore, in this recording head, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

  In the recording head of the present invention, when the width of the plurality of protruding portions along the main scanning direction becomes narrower toward the heating element side, the crossing angle between the main extending portion and the protruding portion can be reduced. Concentration of thermal stress locally can be reduced. Therefore, in the recording head of the present invention, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

  In the recording head of the present invention, the plurality of wirings include a first wiring pattern, and the first wiring pattern is provided along the end on the heat generating element side in the main extending portion and the protruding portion of the second support substrate. In this case, it is possible to reduce the variation in thermal stress applied to the protruding portion between the end of the second support substrate on the heat generating element side and the first wiring pattern. Therefore, in this recording head, electrical disconnection due to thermal stress can be reduced, and reliability can be improved. Further, in this recording head, the plurality of wirings include the second wiring pattern, and the second wiring pattern is formed on the protruding portion when the end on the heating element side is provided along the first wiring pattern. It is possible to reduce the variation of the applied thermal stress between the first wiring pattern and the second wiring pattern. Therefore, in this recording head, electrical disconnection due to thermal expansion can be further reduced, and reliability can be further improved.

  In the recording head of the present invention, the head substrate has a protective layer that covers a part of the plurality of conductive layers, and the protective layer has an end on the wiring substrate side at an end on the heating element side of the second support substrate. When extending along, the variation in thermal stress between the protective layer and the second support substrate can be reduced. Therefore, in the recording head of the present invention, electrical disconnection due to thermal expansion can be further reduced, and reliability can be further improved.

  In the recording head of the present invention, the plurality of wirings are caused by thermal expansion even when the connection areas to the plurality of conductive layers are smaller at both ends in the main scanning direction of the plurality of driving elements than between the plurality of driving elements. Electrical disconnection can be further reduced, and reliability can be further increased.

  The recording apparatus of the present invention includes the recording head of the present invention and a transport mechanism for transporting a recording medium. Therefore, the recording apparatus of the present invention can enjoy the effects of the above-described recording head. Therefore, according to the recording apparatus of the present invention, reliability can be improved.

1 is a plan view illustrating a schematic configuration of a first embodiment of a thermal head that is an example of an embodiment of a recording head of the present invention. 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 plan view of a main part of a head substrate constituting the thermal head shown in FIG. 1. FIG. 4 is a plan view in which a protective layer of the head base shown in FIG. 3 is omitted. FIG. 5 is a sectional view taken along line VV shown in FIG. 3. It is the top view to which the principal part of the wiring base | substrate which comprises the thermal head shown in FIG. 1 was expanded. It is a top view which shows schematic structure of 2nd Embodiment of the thermal head which is an example of embodiment of the recording head of this invention. It is the top view to which the principal part of the thermal head shown in FIG. 7 was expanded. It is the top view to which the principal part of the wiring base | substrate which comprises the thermal head shown in FIG. 7 was expanded. It is a top view which shows schematic structure of 3rd Embodiment of the thermal head which is an example of embodiment of the recording head of this invention. It is the top view to which the principal part of the thermal head shown in FIG. 10 was expanded. It is the top view to which the principal part of the wiring base | substrate which comprises the thermal head shown in FIG. 10 was expanded. It is a top view which shows schematic structure of 4th Embodiment of the thermal head which is an example of embodiment of the recording head of this invention. It is the top view to which the principal part of the thermal head shown in FIG. 13 was expanded. It is the top view to which the principal part of the wiring base | substrate which comprises the thermal head shown in FIG. 13 was expanded. 1 is a diagram illustrating a schematic configuration of a thermal printer which is an example of an embodiment of a recording apparatus of the present invention. FIG. 7 is a plan view showing a modification of the wiring substrate constituting the thermal head shown in FIG. 6. FIG. 7 is a plan view showing a modification of the wiring substrate constituting the thermal head shown in FIG. 6. FIG. 7 is a plan view showing a modification of the wiring substrate constituting the thermal head shown in FIG. 6. FIG. 13 is a plan view showing a modification of the wiring substrate constituting the thermal head shown in FIG. 12.

<First Embodiment of Recording Head>
A thermal head 10 which is an example of an embodiment of the recording head of the present invention shown in FIGS. 1 to 6 includes a head substrate 20, a wiring substrate 30, and a mounting substrate 40.

  The head base 20 includes a head substrate 21, a heat storage layer 22, an electric resistance layer 23, a conductive layer 24, a protective layer 25, and a control IC 26 as a control element.

The head substrate 21 has a function of supporting the heat storage layer 22, the electric resistance layer 23, the conductive layer 24, the protective layer 25, and the control IC 26. The head substrate 21 is configured in a rectangular shape extending in the main scanning directions D1 and D2 in plan view. Here, the “plan view” means a view in the D6 direction in the thickness directions D5 and D6. Examples of a material for forming the head substrate 21 include ceramics such as alumina ceramics, resin materials such as epoxy resins and silicon resins, silicon materials, and insulating materials such as glass materials. In this embodiment, the head substrate 21 is made of alumina ceramics, and its thermal expansion coefficient is about 7.3 × 10 ⁻⁶ K ⁻¹ . It should be noted that the thermal expansion coefficient of the head base 20 of the present embodiment is substantially equal to the thermal expansion coefficient of the constituent material of the head substrate 21 that is a base material. Further, a heat storage layer 22 is provided over the entire upper surface of the head substrate 21 in the thickness direction D5, D6 on the D5 direction side.

  The heat storage layer 22 has a function of temporarily storing a part of heat generated in a heat generating portion 23a described later of the electric resistance layer 23. That is, the heat storage layer 22 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 23a. An example of a material for forming the heat storage layer 22 is quartz glass. The heat storage layer 22 has a base portion 22a and a protruding portion 22b.

  The base portion 22 a is provided in a substantially flat shape over the entire top surface of the head substrate 21.

  The protrusion 22b is a part that contributes to pressing the recording medium favorably against the protective layer 25 located on the heat generating part 23a. The protrusion 22b protrudes in the direction D5 in the thickness directions D5 and D6 from the base 22a. Further, the protruding portion 22b is formed in a strip shape extending in the main scanning directions D1 and D2. The protrusion 22b has a substantially semi-elliptical cross section in the sub-scanning directions D3 and D4 orthogonal to the main scanning directions D1 and D2.

  The electrical resistance layer 23 has a heat generating portion 23a that functions as a heat generating element that generates heat when power is supplied. The electrical resistance layer 23 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 24. Examples of the material for forming the electric resistance layer 23 include TaN-based materials, TaSiO-based materials, TaSiNO-based materials, TiSiO-based materials, TiSiCO-based materials, and NbSiO-based materials. 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. The electrical resistance layer 23 is provided on the heat storage layer 22, and a part thereof is provided on the protrusion 22b. In the present embodiment, a portion of the electrical resistance layer 23 to which a voltage is applied from the conductive layer 24 where the conductive layer 24 is not formed functions as the heat generating portion 23a.

  The heat generating part 23a is a part that functions as a heat generating element that generates heat by supplying power. The heat generating portion 23a is configured such that the heat generation temperature due to power supply from the conductive layer 24 is in the range of 200 ° C. or higher and 550 ° C. or lower, for example. The heat generating portion 23a is located on the protruding portion 22b of the heat storage layer 22, and is arranged at substantially the same distance along the main scanning directions D1 and D2. In addition, each of the heat generating portions 23a is configured in a rectangular shape in plan view. Further, the heat generating portion 23a is configured to have substantially the same width along the main scanning directions D1 and D2. Further, the heat generating portion 23a 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 distance between the center of one heat generating portion 23a and the center of another heat generating portion 23a adjacent to the heat generating portion 23a include a range of 5.2 μm or more and 84.7 μm or less.

  The conductive layer 24 is provided on the electric resistance layer 23. The conductive layer 24 includes a first conductive layer 241, a second conductive layer 242, and a third conductive layer 243. As a material for mainly forming the conductive layer 24, for example, any one metal of aluminum, gold, silver, and copper, or an alloy thereof can be given.

  One end of each first conductive layer 241 is electrically connected independently to one end of each heat generating portion 23a. The first conductive layer 241 contributes to supplying power to the heat generating portion 23a.

  The second conductive layer 242 has an end connected to the other end of the plurality of heat generating portions 23 a and the wiring substrate 30. The second conductive layer 242 is paired with the first conductive layer 241 and contributes to supplying power to the heat generating portion 23a.

  The third conductive layer 243 is disposed away from the first conductive layer 241. The third conductive layer 243 is provided between the plurality of drive ICs 26 and in regions at both ends of the plurality of drive ICs 26 in the main scanning directions D1 and D2. That is, the third conductive layer 243 is provided on both sides of the drive IC 26 in the main scanning directions D1 and D2. The third conductive layer 243 is connected to the control IC 26 and the wiring substrate 30. The third conductive layer 243 of the present embodiment includes a first control unit 243a, a second control unit 243b, and a third control unit 243c.

  The first control unit 243a contributes to supply power source power for the control IC 26. A plurality of the first control units 243a are provided and are arranged along the main scanning directions D1 and D2. The first control unit 243a is provided between the drive ICs 26 in the main scanning directions D1 and D2 and on both sides of the arranged drive ICs 26. Further, in the first control unit 243a, the end on the D4 direction side in the sub scanning directions D3 and D4 extends along the main scanning directions D1 and D2.

  The second control unit 243b is connected to the first conductive layer 241 via the control IC 26. A plurality of second control units 243b are provided and are arranged along the main scanning directions D1 and D2. The second control unit 243b is provided between the drive ICs 26 in the main scanning directions D1 and D2 and on both sides of the arranged drive ICs 26. Further, in the second control unit 243b, the end on the D4 direction side in the sub scanning directions D3 and D4 extends along the main scanning directions D1 and D2.

  The third control unit 243c contributes to transmitting the drive signal of the control IC 26. Examples of such a drive signal include a selection drive signal for selecting the heat generating unit 23a to be driven and a timing signal for controlling the timing for driving the heat generating unit 23a. A plurality of third control units 243c are provided, and are provided at both ends of the drive ICs 26 arranged along the main scanning directions D1 and D2.

  The protective layer 25 includes a first protective layer 251 and a second protective layer 252. In FIG. 4, the protective layer 25 is omitted.

The first protective layer 251 has a function of protecting the heat generating portion 23 a and a part of the conductive layer 24. The first protective layer 251 covers the heat generating portion 23 a and part of the first conductive layer 241 and part of the second conductive layer 242 of the conductive layer 24. As a material mainly forming the first protective layer 251, for example, diamond-like carbon material, SiC-based material, SiN-based material, SiCN-based material, SiON-based material, SiONC-based material, SiAlON-based material, SiO ₂ -based material, Ta ₂ O ₅ -based material, TaSiO-based material, TiC-based material, TiN-based material, TiO ₂ -based material, TiB ₂ -based material, AlC-based material, and AlN-based material Al ₂ O ₃ -based material, ZnO-based material, B ₄ C-based material, and BN-based material. Here, “diamond-like carbon material” refers to a film in which the proportion of carbon atoms (C atoms) taking sp ³ hybrid orbits is in the range of 1 atomic% to less than 100 atomic%. In addition, the “material mainly composed of” herein means that the principal material is 50% by mass or more based on the whole, and for example, an additive may be included.

  The second protective layer 252 has a function of protecting a part of the first conductive layer 241, a part of the second conductive layer 242, and a part of the third conductive layer 243 of the conductive layer 24. Part of the conductive layer 241, part of the second conductive layer 242, and part of the third conductive layer 243 are covered. Examples of the material for forming the second protective layer 252 include thermosetting or ultraviolet curable resins such as epoxy resins, silicone resins, and fluorine resins. In the present embodiment, the second protective layer 252 is a second protective layer having fluidity on each of the first conductive layer 241, the second conductive layer 242, and the third conductive layer 243 after the first protective layer 251 is formed. It is formed by applying the precursor of the layer 252 and curing the precursor. As this precursor, what diluted the above-mentioned resin material using the organic solvent is mentioned, for example. The second protective layer 252 does not cover the region including the end of the first conductive layer 241 and the second conductive layer 242 on the D4 direction side in the sub-scanning directions D3 and D4, and does not cover the first conductive layer 241 and the second conductive layer 252. The end portion of the conductive layer 242 is exposed from the second protective layer 252. Further, the second protective layer 252 does not cover a region including both ends of the third conductive layer 243, and both ends of the third conductive layer 243 are exposed from the second protective layer 252. In the second protective layer 252 of this embodiment, the end on the D4 direction side in the sub-scanning directions D3 and D4 extends along the end on the D3 direction side in the sub-scanning directions D3 and D4 of the wiring substrate 30 described later.

  The control IC 26 has a function of controlling the heat generation of the plurality of heat generating portions 23a. The control IC 26 is disposed away from the heat generating portion 23a in the sub-scanning directions D3 and D4. The control ICs 26 are arranged along the main scanning directions D1 and D2. The control IC 26 is connected to the other ends of the plurality of first conductive layers 241 and one end of the third conductive layer 243. By adopting such a configuration, the control IC 26 performs electrical connection between the first conductive layer 241 and the second control unit 243b based on the drive signal input via the third control unit 243c of the third conductive layer 243. By controlling the general connection, the power supplied to the heat generating portion 23a can be selectively controlled to control the heat generation.

  The wiring substrate 30 includes a first support substrate 31, a second support substrate 32, a wiring layer 33, and an external connection member 34.

The first support substrate 31 and the second support substrate 32 have a function of supporting the wiring layer 33. Examples of the material for forming the first support substrate 31 include ceramics, resins, and composite materials of ceramics and resins. Examples of this ceramic include alumina ceramics, aluminum nitride ceramics, silicon nitride ceramics, glass ceramics, and mullite ceramics. Examples of this resin include thermosetting or ultraviolet curable resins such as epoxy resins, polyimide resins, acrylic resins, phenol resins, and polyester resins. Among these forming materials, it is more preferable to employ a flexible resin such as a polyimide resin, an epoxy resin, and an acrylic resin. Here, “flexibility” means that the flexural modulus defined by JIS standard K7171: 1994 is, for example, 2.5 × 10 ³ N / mm ² or more and 4.5 × 10 ³ N / mm ² or less. Say. The first support substrate 31 of this embodiment is formed of a polyimide resin. The first support substrate 31 employing this polyimide resin has a thermal expansion coefficient of about 10 × 10 ⁻⁶ K ⁻¹ . Further, the first support substrate 31 of the present embodiment is configured in a rectangular shape extending in the main scanning directions D1 and D2 in plan view. Further, the first support substrate 31 has one end 31a on the D3 direction side (the heat generating portion 23a side) in the sub-scanning directions D3 and D4 extending along the main scanning directions D1 and D2.

The second support substrate 32 functions as a pair with the first support substrate 31 to ensure electrical insulation of the wiring layer 33. Here, “insulation” refers to the extent to which current does not substantially flow. For example, the electrical resistivity is 1.0 × 10 ¹² Ω · cm or more. Examples of the material forming the second support substrate 32 include the materials mentioned in the first support substrate 31 such as ceramics, resin, and a composite material of ceramics and resin. The second support substrate 32 of this embodiment is formed of the same polyimide resin as that of the first support substrate 31. The second support substrate 32 of the present embodiment is configured to include a main extending portion 321 and a protruding portion 322.

  The main extension 321 is configured in a rectangular shape extending in the main scanning directions D1 and D2 in plan view. Further, the main extending portion 321 has one end 321a on the D3 direction side (the heat generating portion 23a side) in the sub scanning directions D3 and D4 extending along the main scanning directions D1 and D2. That is, one end 321 a of the main extending portion 321 extends so as to overlap the one end 31 a of the first support substrate 31.

  The protruding portion 322 protrudes from the one end 321a of the main extending portion 321 to the D3 direction side (the heat generating portion 23a side) in the sub-scanning directions D3 and D4. The protrusions 322 are provided so as to be located between the plurality of drive ICs 26 and in the regions at both ends of the plurality of drive ICs 26 in the main scanning directions D1 and D2. That is, the protrusions 322 are provided so as to be located on both sides of the drive IC 26 in the main scanning directions D1 and D2. Further, the protruding portion 322 is configured such that the width along the main scanning directions D1 and D2 becomes narrower toward the D3 direction side (the heat generating portion 23a side) in the sub-scanning directions D3 and D4. That is, the protrusion 322 is configured such that the width along the main scanning directions D1 and D2 becomes narrower as it protrudes toward the heat generating part 23a. In addition, the protruding portion 322 has an acute angle with respect to both ends 322a in the main scanning directions D1 and D2 and one end 321a of the main extending portion 321. Here, the “intersection angle” refers to an angle at which the direction in which the end 322a in the main scanning directions D1 and D2 of the protrusion 322 extends intersects the direction in which the one end 321a of the main extension 321 extends. Further, the protruding portion 322 has one end 322b on the D3 direction side (the heat generating portion 23a side) in the sub scanning directions D3 and D4 extending along the main scanning directions D1 and D2. Furthermore, the protrusions 322 located at both ends of the protrusions 322 arranged in the main scanning directions D1 and D2 have a wider width along the main scanning directions D1 and D2 than the other protrusions 322. Yes.

The wiring layer 33 contributes to supplying an electric signal that contributes to driving the heat generating portion 23 a to the head substrate 20. The wiring layer 33 is provided between the first support substrate 31 and the second support substrate 32 in the thickness directions D5 and D6. As a material for forming the wiring layer 33, for example, any one metal of aluminum, gold, silver, and copper, or an alloy thereof can be used. The wiring layer 33 of this embodiment is formed of copper. The thermal expansion coefficient of the wiring layer 33 employing copper is about 17 × 10 ⁻⁶ K ⁻¹ . That is, the thermal expansion coefficient of the wiring layer 33 is different from the thermal expansion coefficients of the first support substrate 31 and the second support substrate 32. Therefore, the wiring base 30 of this embodiment has locally different thermal expansion coefficients due to the routing of the wiring layer 33. In a region where the thermal expansion coefficients are locally different, a relatively large thermal stress is applied. The wiring layer 33 is mechanically and electrically connected to the conductive layer 24 via a conductive bonding material. Examples of the “conductive bonding material” include various solder materials and anisotropic conductive materials in which a conductive material is mixed in a resin. The wiring layer 33 of this embodiment includes a first wiring layer 331, a second wiring layer 332, a third wiring layer 333, and a fourth wiring layer 334.

  The first wiring layer 331 is connected to the first control unit 243 a of the third conductive layer 243, and one end thereof is connected to the external connection member 34. The first wiring layer 331 contributes to transmitting the power supply power of the control IC 26 from the external connection member 34 to the drive IC 26. The first wiring layer 331 according to the present embodiment includes a first main extension 331a and a first extension 331b. The first wiring layer 331 is provided so as to overlap a part of the second control unit 243b of the third conductive layer 243 in the thickness directions D5 and D6. In order to reduce the short circuit between the first wiring layer 331 and the second control unit 243b, a part of the second protective layer 252 extends between the first wiring layer 331 and the second control unit 243b. Yes.

The first main extension 331 a is provided between the first support substrate 31 and the main extension 321 of the second support substrate 32. The first main extending portion 331a, an end 331a ₁ in the sub-scanning direction D3, D4 in D3 direction (heating portion 23a side) extends along the main scanning direction D1, D2. That is, the first main extension 331 a extends along the one end 321 a of the main extension 321. A plurality of the first main extending portions 331a are provided in one first wiring layer 331, and are arranged along the main scanning directions D1 and D2. The first main extending portions 331a are positioned on the D4 direction side of the drive IC 26 in the sub-scanning directions D3 and D4.

The first extending portion 331 b is provided on the protruding portion 322 of the second support substrate 32. A plurality of first extending portions 331b are provided in one first wiring layer 331 and are arranged along the main scanning directions D1 and D2. Further, the first extending portion 331b is provided between the first main extending portions 331a and electrically connects the first main extending portions 331a in series. The first extending portions 331b are located between the driving ICs 26 in the main scanning directions D1 and D2 and on both ends of the driving ICs 26 arranged along the main scanning directions D1 and D2. The first extending portion 331b of the present embodiment includes a first main trunk region 331b _1, is configured to include a first Fukunobe region 331b _2.

In the first main trunk region 331b ₁ , the end on the D3 direction side (the heat generating portion 23a side) in the sub-scanning directions D3 and D4 extends along the main scanning directions D1 and D2. That is, the first main trunk region 331b ₁ extends along the one end 322b of the protruding portion 322. In the first extension part 331b, the first wiring layer 331 and the first control part 243a of the third conductive layer 243 are electrically connected. That is, the first wiring layer 331, the first control unit 243a of the third conductive layer 243 through the first main trunk region 331b ₁ is electrically connected across the main scanning direction D1, D2. The first main trunk region 331b ₁ has a length along the sub-scanning directions D3 and D4 and a length along the sub-scanning directions D3 and D4 in the first control unit 243a to which the first main trunk region 331b ₁ is connected. It is comprised so that it may become short compared with.

The first sub-extension region 331b ₂ has both ends in the main scanning directions D1 and D2 extending along the ends 322a of the protrusions 322 in the main scanning directions D1 and D2. One end of the first sub-extension region 331b ₂ is electrically connected in series to both ends of the first main trunk region 331b ₁ in the main scanning directions D1 and D2. The other end of the first sub-extension region 331b ₂ is electrically connected in series to the end of the first main extension portion 331a in the main scanning directions D1 and D2.

  The second wiring layer 332 has one end connected to the second control unit 243 b of the third conductive layer 243 and the other end connected to the external connection member 34. The second wiring layer 332 contributes to electrically connecting the other end of the heat generating portion 23a to the reference potential point. The second wiring layer 332 according to the present embodiment includes a second main extension 332a and a second extension 332b.

The second main extension 332 a is provided between the first support substrate 31 and the main extension 321 of the second support substrate 32. The second main extending portion 332a, an end 332a ₁ in the sub-scanning direction D3, D4 in D3 direction (heating portion 23a side) extends along the main scanning direction D1, D2. That is, the second main extension 332 a extends along the one end 321 a of the main extension 321. The second main extending portion 332a extends from one end to the other end in the main scanning directions D1 and D2 of the arranged driving ICs 26, and is provided to extend outward from both ends of the driving ICs 26. Yes.

The second extending portion 332 b is provided on the protruding portion 322 of the second support substrate 32. A plurality of second extending portions 332b are provided in one second wiring layer 332, and are arranged along the main scanning directions D1 and D2. The second extending portions 332b are located between the driving ICs 26 in the main scanning directions D1 and D2 and on both ends of the driving ICs 26 arranged along the main scanning directions D1 and D2. Second extending portions 332b of the present embodiment, the second main trunk region 332b _1, and the second Fukunobe region 332b _2, is configured to include a second branch region 332b _3.

In the second main trunk region 332b ₁ , the end on the D3 direction side (the heat generating portion 23a side) in the sub-scanning directions D3 and D4 extends along the main scanning directions D1 and D2. That is, the second main trunk region 332b ₁ extends along the one end 322b of the protruding portion 322. In the second extension part 332b, the first wiring layer 331 and the second control part 243b of the third conductive layer 243 are electrically connected. That is, the second wiring layer 332, the second control unit of the third conductive layer 243 through the second main trunk region 332b ₁ 243b is electrically connected across the main scanning direction D1, D2. The second main trunk region 332b ₁ has a length along the sub-scanning directions D3 and D4 and a length along the sub-scanning directions D3 and D4 in the second control unit 243b to which the second main trunk region 332b ₁ is connected. It is comprised so that it may become short compared with.

The second sub-extending region 332b ₂ has both ends in the main scanning directions D1 and D2 extending along the ends 322a of the protrusions 322 in the main scanning directions D1 and D2. One end of the second sub extension region 332b ₂ is electrically connected to the second main trunk region 332b ₁ in the main scanning directions D1 and D2. The other end of the first sub extended region 332b ₂ is electrically connected to the end 332a ₁ of the second main extended portion 332a in the main scanning directions D1 and D2. In other words, the second sub extension region 332b ₂ provided in one second extension portion 332b electrically connects the second main trunk region 332b ₁ and the second main extension portion 332a in parallel.

The second branch region 332b ₃ is located between the second sub-extension regions 332b ₂ in the main scanning directions D1 and D2. The second branch region 332b ₃ electrically connects the second main trunk region 332b ₁ and the second main extension portion 332a in parallel with the second sub-extension region 332b ₂ . In other words, the second branch region 332b ₃ has a function of enhancing the electrical connection between the second main trunk region 332b ₁ and the second main extension 332a. The second branch region 332b ₃ of the present embodiment is provided along the sub-scanning directions D3 and D4.

  The third wiring layer 333 has one end connected to the third control unit 243 c of the third conductive layer 243 and the other end connected to the external connection member 34. The third wiring layer 333 contributes to transmitting the drive signal of the control IC 26 from the external connection member 34 to the drive IC 26. The third wiring layer 333 of this embodiment is provided with one end extending to the protruding portion 322 of the second support substrate 32 positioned at both ends in the main scanning directions D1 and D2.

  The fourth wiring layer 334 has one end connected to the second conductive layer 242 and the other end connected to the external connection member 34. The fourth wiring layer 334 contributes to supplying power to the heat generating portion 23a. The fourth wiring layer 334 of the present embodiment is provided so that one end extends to the protruding portion 322 of the second support substrate 32 located at both ends in the main scanning directions D1 and D2. The fourth wiring layer 334 is located outside the wiring layer 33. The fourth conductive layer 334 is provided along the other three sides excluding the one side where the projecting portion 322 of the second support substrate 32 is provided.

  The external connection member 34 contributes to supplying an electric signal contributing to driving the heat generating portion 23 a to the head base 20. The external connection member 34 is electrically and independently connected to each of the first wiring layer 331, the second wiring layer 332, the third wiring layer 333, and the fourth wiring layer 334 of the wiring layer 33.

  The mounting substrate 40 has a function as a mounting base material for the head base 20 and the wiring substrate 30. The mounting substrate 40 has a function of mounting the head substrate 20 and the wiring substrate 30. A head substrate 20 and a wiring substrate 30 are mounted on the wiring substrate 40. Examples of the material for forming the mounting substrate 40 include aluminum, copper, iron, and ceramic materials such as alumina ceramics.

  The thermal head 10 includes a head substrate 21, a plurality of heat generating portions 23a arranged on the head substrate 21 along the main scanning directions D1 and D2, and a plurality of heating heads 23a arranged along the main scanning directions D1 and D2. Are provided on both sides in the main scanning directions D1 and D2 of each of the plurality of drive ICs 26 connected to the plurality of heat generation units 23a or the plurality of drive ICs 26. A head substrate 20 having a plurality of conductive layers 24, a first wiring substrate 31, a second wiring substrate 32 provided on the first wiring substrate 31, a first wiring substrate 31 and And a wiring substrate 30 having a plurality of wiring layers 33 connected to the plurality of conductive layers 24 provided between the second wiring boards 32. 1 wiring base A main extending portion 321 extending along the end 31a on the heat generating portion 23a side of the plurality 31 and a plurality of protruding portions 322 protruding from the end 31a of the first wiring substrate 31 toward the heat generating portion 23a side in the sub-scanning directions D3 and D4. The plurality of protrusions 322 have heat generating part 23a ends in the sub-scanning directions D3 and D4 along the main scanning directions D1 and D2, and the plurality of wiring layers 33 include a plurality of protrusions. The plurality of first extending portions 331 b and the second extending portions 332 b extending to the 322 include the plurality of first extending portions 331 b and the second extending portions 332 b. Are connected along the main scanning directions D1 and D2. For this reason, in the thermal head 10, the occurrence of variations in thermal stress applied to the wiring substrate 30 between the ends 321 a, 322 a, 322 b of the second support substrate 32 on the heat generating portion 23 a side and the first wiring layer 331 is reduced. be able to. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

In the thermal head 10, a plurality of conductive layers 24, since the end 331b ₁ and 332b ₁ of the wiring substrate 30 side extends along the main scanning direction D1, D2, an end of the heat generating portion 23a of the second support substrate 32 Variations in thermal expansion between 321a, 322a, and 322b and the protruding portion 322 can be reduced. Therefore, in the thermal head 10, electrical disconnection due to thermal expansion can be reduced, and reliability can be improved.

  In the thermal head 10, the width of the plurality of protrusions 322 along the main scanning directions D <b> 1 and D <b> 2 becomes narrower toward the heat generating part 23 a side, so that the intersection angle between the main extension part 321 and the protrusion part 322 is reduced. It is possible to reduce the concentration of thermal stress locally. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be further improved.

  In the thermal head 10, the plurality of wiring layers 33 include a first wiring layer 331, and the first wiring layer 331 is located on the heat generating portion 23 a side of the main extending portion 321 and the protruding portion 322 of the second wiring substrate 32. Since the thermal stress applied to the projecting portion 322 is provided along the end, the variation between the ends 321a, 322a, and 322b of the second support substrate 32 on the heat generating portion 23a side and the first wiring layer 331 is caused. Can be reduced. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

  Further, in the thermal head 10, the plurality of wiring layers 33 include the second wiring layer 332, and the second wiring layer 332 is provided along the first wiring layer 331 at the end on the heat generating portion 23 a side. Therefore, variation in thermal stress applied to the protruding portion 322 between the first wiring layer 331 and the second wiring layer 332 can be reduced. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be further reduced, and reliability can be further improved.

  In the thermal head 10, the head substrate 20 has a second protective layer 252 that covers a part of the plurality of conductive layers 24, and the second protective layer 252 has an end on the wiring substrate 30 side at the second wiring substrate. 32 extends along the ends 322 a, 322 a, and 322 b on the side of the heat generating portion 23 a, it is possible to reduce the occurrence of variations in thermal stress between the second protective layer 252 and the second wiring substrate 32. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.

In the thermal head 10, the plurality of wiring layers 33 have a smaller connection area to the plurality of conductive layers 24 at both ends in the main scanning directions D <b> 1 and D <b> 2 of the plurality of driving ICs 26 than between the plurality of driving ICs 26. Electrical disconnection due to thermal expansion can be further reduced, and reliability can be further increased.
<Second Embodiment of Recording Head>
The thermal head 10A shown in FIG. 7 is different from the thermal head 10 in that the wiring base 30A is used instead of the wiring base 30. Other configurations of the thermal head 10A are the same as those described above with respect to the thermal head 10. Further, in the description of the present embodiment, the overlapping contents between the thermal head 10 and the thermal head 10A are omitted.

  The wiring substrate 30A is different from the wiring substrate 30 in that a wiring layer 33A is provided instead of the wiring layer 33. Other configurations of the wiring substrate 30A are the same as those described above with respect to the wiring substrate 30.

  The wiring layer 33A is different from the wiring layer 33 in that it includes a second wiring layer 332A instead of the second wiring layer 332. Other configurations of the wiring layer 33A are the same as those described above with respect to the wiring layer 33.

  The second wiring layer 332A is different from the second wiring layer 332 in that the second wiring layer 332A includes a second extending portion 332Ab instead of the second extending portion 332b. Other configurations of the second wiring layer 332A are the same as those described above with respect to the second wiring layer 332.

The second extending portion 332Ab includes a second main trunk region 332b _1, is configured to include a second Fukunobe region 332b _2. The configuration of the second main trunk region 332b ₁ and the second secondary extension region 332b ₂ is the same as described above.

The thermal head 10A includes a head substrate 21, a plurality of heat generating portions 23a arranged on the head substrate 21 along the main scanning directions D1 and D2, and a plurality of heating units 23a arranged along the main scanning directions D1 and D2. Are provided on both sides in the main scanning directions D1 and D2 of each of the plurality of drive ICs 26 connected to the plurality of heat generation units 23a or the plurality of drive ICs 26. A head substrate 20 having a plurality of conductive layers 24, a first wiring substrate 31, a second wiring substrate 32 provided on the first wiring substrate 31, a first wiring substrate 31 and And a wiring substrate 30A having a plurality of wiring layers 33A connected to the plurality of conductive layers 24 provided between the second wiring boards 32. 1 A main extending portion 321 extending along the end 31a on the heat generating portion 23a side of the line substrate 31 and a plurality of protrusions protruding from the end 31a of the first wiring substrate 31 toward the heat generating portion 23a in the sub-scanning directions D3 and D4. The plurality of projecting portions 322 have heat generating portion 23a ends in the sub-scanning directions D3 and D4 along the main scanning directions D1 and D2, and the plurality of wiring layers 33A include a plurality of wiring layers 33A. The plurality of first extending portions 331b and second extending portions 332Ab extending to the protruding portion 322 have a plurality of first extending portions 331b and second extending portions 332Ab. The layer 24 is connected along the main scanning directions D1 and D2. For this reason, in the thermal head 10, the occurrence of variations in thermal stress applied to the wiring substrate 30 between the ends 321 a, 322 a, 322 Ab on the heat generating portion 23 a side of the second support substrate 32 and the first wiring layer 331 is reduced. be able to. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.
<Third Embodiment of Recording Head>
The thermal head 10B shown in FIG. 10 is different from the thermal head 10 in that the wiring base 30B is used instead of the wiring base 30. Other configurations of the thermal head 10B are the same as those described above with respect to the thermal head 10. Further, in the description of the present embodiment, overlapping contents between the thermal head 10 and the thermal head 10B are omitted.

  The wiring base 30 </ b> B is different from the wiring base 30 in that a wiring layer 33 </ b> B is provided instead of the wiring layer 33. Other configurations of the wiring substrate 30B are the same as those described above with respect to the wiring substrate 30.

  The wiring layer 33B is different from the wiring layer 33 in that a second wiring layer 332B is provided instead of the second wiring layer 332. Other configurations of the wiring layer 33B are the same as those described above with respect to the wiring layer 33.

  The second wiring layer 332B is different from the second wiring layer 332 in that a second extending portion 332Bb is provided instead of the second extending portion 332b. Other configurations of the second wiring layer 332B are the same as those described above with respect to the second wiring layer 332.

The second extending portion 332Bb has a second main trunk region 332b _1, and the second Fukunobe region 332Bb _2, is configured to include a second branch region 332Bb _3. The configuration of the second main trunk region 332b ₁ is the same as described above.

The second sub extended region 332Bb ₂ has both ends in the main scanning directions D1 and D2 extending along the sub scanning direction. The second Fukunobe region 332Bb ₂ has one end electrically connected to the second main trunk region 332b ₁ in the main scanning direction D1, D2. The other end of the first sub extended region 332Bb ₂ is electrically connected to the end 332a ₁ of the second main extended portion 332a in the main scanning directions D1 and D2. In other words, the second sub extension region 332Bb ₂ provided in one second extension portion 332Bb electrically connects the second main trunk region 332b ₁ and the second main extension portion 332a in parallel.

The second branch region 332Bb ₃ is provided along the sub-scanning directions D3 and D4. That is, the second branch region 322Bb ₃ is also provided along the second sub-extension region 332Bb ₂ . The second branch region 332b ₃ is located between the second sub-extension regions 332b ₂ in the main scanning directions D1 and D2. The second branch region 332Bb ₃ is connected to the second main extension region 332b ₁ and the second main extension portion 332a in parallel with the second sub extension region 332b ₂ . In other words, the second branch region 332Bb ₃ has a function of improving electrical connection between the second main trunk region 332b ₁ and the second main extension 332a.

The thermal head 10B includes a head substrate 21, a plurality of heat generating portions 23a arranged on the head substrate 21 along the main scanning directions D1 and D2, and a plurality of heat generating units 23a arranged along the main scanning directions D1 and D2. Are provided on both sides in the main scanning directions D1 and D2 of each of the plurality of drive ICs 26 connected to the plurality of heat generation units 23a or the plurality of drive ICs 26. A head substrate 20 having a plurality of conductive layers 24, a first wiring substrate 31, a second wiring substrate 32 provided on the first wiring substrate 31, a first wiring substrate 31 and And a wiring substrate 30B having a plurality of wiring layers 33B connected to the plurality of conductive layers 24 provided between the second wiring boards 32. 1 A main extending portion 321 extending along the end 31a on the heat generating portion 23a side of the line substrate 31 and a plurality of protrusions protruding from the end 31a of the first wiring substrate 31 toward the heat generating portion 23a in the sub-scanning directions D3 and D4. The plurality of protrusions 322 have heat generating portion 23a ends in the sub-scanning directions D3 and D4 along the main scanning directions D1 and D2, and the plurality of wiring layers 33B include a plurality of wiring layers 33B. The plurality of first extending portions 331b and second extending portions 332Bb extending to the protruding portion 322 have a plurality of first extending portions 331b and second extending portions 332Bb. The layer 24 is connected along the main scanning directions D1 and D2. Therefore, in the thermal head 10, the occurrence of variations in thermal stress applied to the wiring substrate 30 between the ends 321 a, 322 a, 322 Bb of the second support substrate 32 on the heat generating portion 23 a side and the first wiring layer 331 is reduced. be able to. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.
<Fourth Embodiment of Recording Head>
The thermal head 10C shown in FIG. 13 is different from the thermal head 10B in that a wiring base 30C is used instead of the wiring base 30B. Other configurations of the thermal head 10C are the same as those described above with respect to the thermal head 10B. Further, in the description of the present embodiment, overlapping contents between the thermal head 10B and the thermal head 10C are omitted.

  The wiring substrate 30C is different from the wiring substrate 30B in that a wiring layer 33C is provided instead of the wiring layer 33B. Other configurations of the wiring substrate 30C are the same as those described above with respect to the wiring substrate 30B.

  The wiring layer 33C is different from the wiring layer 33B in that the second wiring layer 332C is provided instead of the second wiring layer 332B. The other configuration of the wiring layer 33C is the same as that described above with respect to the wiring layer 33B.

  The second wiring layer 332C is different from the second wiring layer 332B in that a second extending portion 332Cb is provided instead of the second extending portion 332Bb. Other configurations of the second wiring layer 332C are the same as those described above with respect to the second wiring layer 332B.

The second extending portion 332Cb includes a second main trunk region 332b _1, is configured to include a second Fukunobe region 332Bb _2. The configurations of the second main trunk region 332b ₁ and the second secondary extension region 332Bb ₂ are the same as described above.

The thermal head 10C includes a head substrate 21, a plurality of heat generating portions 23a arranged on the head substrate 21 along the main scanning directions D1 and D2, and a plurality of heat generating units 23a arranged along the main scanning directions D1 and D2. Are provided on both sides in the main scanning directions D1 and D2 of each of the plurality of drive ICs 26 connected to the plurality of heat generation units 23a or the plurality of drive ICs 26. A head substrate 20 having a plurality of conductive layers 24, a first wiring substrate 31, a second wiring substrate 32 provided on the first wiring substrate 31, a first wiring substrate 31 and And a wiring substrate 30C having a plurality of wiring layers 33C connected to the plurality of conductive layers 24 provided between the second wiring boards 32. 1 A main extending portion 321 extending along the end 31a on the heat generating portion 23a side of the line substrate 31 and a plurality of protrusions protruding from the end 31a of the first wiring substrate 31 toward the heat generating portion 23a in the sub-scanning directions D3 and D4. The plurality of projecting portions 322 have heat generating portion 23a ends in the sub-scanning directions D3 and D4 along the main scanning directions D1 and D2, and the plurality of wiring layers 33C include a plurality of wiring layers 33C. The plurality of first extending portions 331b and second extending portions 332Cb extending to the protruding portion 322 have a plurality of first extending portions 331b and second extending portions 332Cb. The layer 24 is connected along the main scanning directions D1 and D2. Therefore, in the thermal head 10, the occurrence of variations in thermal stress applied to the wiring substrate 30 between the ends 321 a, 322 a, 322 Cb of the second support substrate 32 on the heat generating portion 23 a side and the first wiring layer 331 is reduced. be able to. Therefore, in the thermal head 10, electrical disconnection due to thermal stress can be reduced, and reliability can be improved.
<Recording device>
FIG. 16 is a diagram showing a schematic configuration of a thermal printer 1 which is an example of an embodiment of a recording medium of the present invention.

  The thermal printer 1 includes a thermal head 10, a transport mechanism 11, and a control mechanism 12.

  The transport mechanism 11 has a function of bringing the recording medium P into contact with the protective layer 25 located on the heat generating portion 23a of the thermal head 10 while transporting the recording medium P in the D3 direction in the sub-scanning directions D3 and D4. is there. 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 P toward the heat generating portion 23a. The platen roller 111 is rotatably supported in contact with the protective layer 25 located on the heat generating portion 23a. The platen roller 111 has a configuration in which an outer surface of a columnar base is covered with an elastic member. This base is made of, for example, a metal such as stainless steel, and this elastic member is made of, for example, butadiene rubber having a thickness dimension in the range of 3 mm to 15 mm.

  The transport rollers 112, 113, 114, and 115 have a function of transporting the recording medium P. That is, the conveyance rollers 112, 113, 114, and 115 supply the recording medium P between the heat generating part 23 a of the thermal head 10 and the platen roller 111 and between the heat generating part 23 a of the thermal head 10 and the platen roller 111. It plays a role of pulling out the recording medium P from 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 is electrically connected to the external connection member 34 of the wiring substrate 30. This control mechanism has a function of supplying power to the heat generating part 23a and the drive IC 26 and supplying a drive signal to the control IC 26.

  The thermal printer 1 includes a thermal head 10. Therefore, the thermal printer 1 can enjoy the effects of the thermal head 10. Therefore, the thermal printer 1 can improve reliability.

  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 spirit of the invention.

  In the wiring substrate 30 of the present embodiment, the second extending portions 332b of the second wiring layer 332 are at the ends in the main scanning directions D1 and D2, and the ends of the protruding portions 322 of the second wiring substrate 32 are in the main scanning directions D1 and D2. Although it is provided along 322a, it is not limited to such a configuration. For example, as shown in FIG. 17, ends positioned on the inner side in the main scanning directions D1 and D2 may be provided along the sub-scanning directions D3 and D4.

  In the wiring substrate 30 of the present embodiment, one end 31a on the D3 direction side in the sub-scanning directions D3 and D4 of the first wiring board 31 is provided along the main scanning directions D1 and D2. It is not a thing. For example, as shown in FIG. 18, the recess 31 </ b> Fb that is recessed in the sub-scanning direction from the one end 31 </ b> Fa may be included. Further, for example, as illustrated in FIG. 19, the protrusion 31Gc may be configured to protrude from the one end 31Ga in the sub-scanning direction.

  In the wiring substrate 30B of the present embodiment, the first extending portion 331b of the first wiring layer 331 is the end of the protruding portion 322 of the second wiring substrate 32 in the main scanning direction D1, D2 of the protruding portion 322 of the second wiring substrate 32. Although it is provided along 322a, it is not limited to such a configuration. For example, as shown in FIG. 20, both ends in the main scanning directions D1 and D2 may be provided along the sub-scanning directions D3 and D4. Similarly, as shown in FIG. 20, in the second wiring board 32, both ends of the protrusion 322 along the main scanning directions D1 and D2 may be provided along the sub-scanning directions D3 and D4.

  In the present embodiment, the reliability of the thermal head with respect to the temperature cycle was tested.

  First, 12 thermal heads A, B, and C according to examples of the present invention and 12 thermal heads D as comparative examples were manufactured. Specifically, first, a head substrate common to the thermal heads A, B, C, and D was manufactured under the following conditions. In this embodiment, the length in the main scanning direction is simply “width” and the length in the sub-scanning direction is simply “length”, except for the description regarding the wiring layer.

<Manufacturing conditions of head substrate common to thermal heads A, B, C, and D>
-Head substrate material: Alumina ceramics-Thermal expansion coefficient of the head substrate: about 7.3 × 10 ⁻⁶ K ⁻¹
-Length of head substrate: about 2.9 × 10 ² mm
-Head substrate width: approx. 78 mm
・ Thickness of the head substrate: about 6.4 × 10 ⁻¹ mm
・ Width of the first control unit: about 11 mm
・ Width of the second control unit: about 11 mm
-Number of drive ICs mounted: 9-Drive IC width: about 11.7 mm
・ Drive IC interval: about 12.3 mm
Next, wiring substrates A, B, C, and D having different configurations in the thermal heads A, B, C, and D were manufactured under the following conditions. Here, the difference in the configuration of the wiring bases A, B, C, and D employed in the thermal heads A, B, C, and D will be described.

  First, the configuration of the wiring substrate D employed in the thermal head D as a comparative example will be described in detail. Next, the difference in configuration between the wiring substrates A, B, and C and the wiring substrate D will be described in detail. The wiring bases A, B, C, and D adopt a common configuration as the main extending portion of the second support substrate and the wiring layer provided on the main extending portion. That is, the wiring bases A, B, C, and D were manufactured by changing the configuration of the first support substrate, the protruding portion of the second support substrate, and the configuration of the wiring layer provided on the protruding portion.

<Manufacturing conditions common to thermal heads A, B, C, and D>
-Material of the first and second support substrates: polyimide resin-Thermal expansion coefficient of the first and second support substrates: about 10 × 10 ^-6 K ^-1
-Thickness of the first and second support substrates: about 5.0 × 10 ⁻² mm
-Length of the first and second support substrates on one end side: about 80 mm
-Length of the first and second support substrates on the other end side: about 4.5 mm
* Adopted different lengths from the center in the main scanning direction.

・ Width of the first and second support substrates: about 228.5 mm
-Distance between the opposite ends of the protrusions: about 15.6 mm
-Maximum width of region along main scanning direction of protrusion: about 6.0 mm
-Maximum width of the region along the main scanning direction of the protruding portions at both ends: about 10.3 mm
-Protruding length of the protruding part: about 2.5mm
-Material of the wiring layer: Copper-Thermal expansion coefficient of the wiring layer: About 17 x ^10-6 K- ¹
-Wiring layer thickness: about 35 × 10 ⁻³ mm
-Length in the direction orthogonal to the direction in which the first wiring layer extends: about 0.2 mm
-Length in the direction orthogonal to the direction in which the second wiring layer extends: about 0.5 mm
-Position of external connection member: Approximately 4.5 mm from one end
・ Width of external connection member: about 4.5mm
-Length of external connection member: about 27.9 mm
In the second support substrate of the wiring substrate D, the crossing angle between both end surfaces of the protruding portion in the main scanning direction and the end surface of the main extending portion in the sub scanning direction on the heat generating element side was set to 90 degrees. Moreover, the structure of the wiring layer of the wiring substrate D is such that the first extending portion of the first wiring pattern extends along the protruding portion of the second support substrate. That is, the first wiring pattern of the wiring substrate D includes the first main region of the first extending portion and the end of the protruding portion on the heating element side, the first sub extending region of the first extending portion, and the protruding portion. It was provided along both ends in the main scanning direction. In addition, in the wiring layer of the wiring substrate D, the second wiring pattern is composed of the second sub-extension region and the second branch region. That is, in the second wiring pattern of the wiring base D, the second extending portion does not include the second main region. In the second wiring pattern of the wiring substrate D, the second sub-extending region and the second branch region of the second extending portion and the both ends of the protruding portion in the main scanning direction are provided. Further, the first support substrate of the wiring substrate D has a recessed portion in which the end on the heat generating element side in the sub-scanning direction is recessed on the opposite side. The hollow portion is aligned with the protruding portion of the second support substrate in the sub-scanning direction. That is, the wiring substrate D is designed so that the exposed area of the wiring layer is increased by the depression.

<Structure of wiring substrate D>
-The length of the dent: about 0.9mm
The second support substrate of the wiring substrate A is different from the wiring substrate D in that the crossing angle between both end surfaces of the protruding portion in the main scanning direction and the end surface of the main extending portion in the sub scanning direction is 60 degrees. Designed as follows. In addition, the first support substrate of the wiring substrate A was designed such that the end on the heat generating element side in the sub-scanning direction extends along the main scanning direction. That is, the first support substrate of the wiring substrate A does not have a recess. The wiring layer of the wiring substrate A was manufactured based on the same design as the wiring layer of the wiring substrate D.

  The second support substrate of the wiring substrate B is different from the wiring substrate D in that the crossing angle between both end surfaces of the protruding portion in the main scanning direction and the end surface of the main extending portion in the sub scanning direction is 60 degrees. Designed. In addition, the conductive layer of the wiring base B was extended along the first extending portion of the first wiring pattern along the protruding portion of the second support substrate. That is, the first wiring pattern of the wiring base B includes the first main region of the first extending portion and the end of the protruding portion on the heating element side, the first sub extending region of the first extending portion, and the protruding portion. It was provided along both ends in the main scanning direction. Therefore, the first sub extended region intersects at about 60 degrees with respect to the main scanning direction. The second wiring pattern of the wiring substrate B was manufactured based on the same design as the second wiring pattern of the wiring substrate D. The first support substrate of the wiring base B was manufactured based on the same design as the first support substrate of the wiring base D.

  The wiring substrate C has the same design as the wiring substrate B except for the second wiring pattern of the conductive layer. In the second wiring pattern of the wiring substrate C, the second extending portion includes a second main trunk region and a second sub-extending region. Further, the second wiring pattern of the wiring substrate C was provided along the first wiring pattern. That is, the second wiring pattern of the wiring substrate C includes the second main region of the second extension portion and the first main region of the first extension portion, the second sub extension region of the second extension portion, and the second main extension region. It provided along with the 1st sub extension area | region of 1 extension part.

  Next, the head base and wiring bases A, B, C, and D were welded using solder. Further, the welded head substrate and wiring substrate were bonded to a heat radiating plate to manufacture thermal heads A, B, C, and D.

<Solder conditions>
-Joining method: Solder welding-Bonding material: Lead-free solder <Conditions for heat sink>
・ Material of heat sink: Aluminum ・ Thickness of heat sink: Approximately 50 mm
・ Heat sink length: approx. 80mm
・ Width of heat sink: About 2.3 × 10 ² mm
Next, using the thermal shock device (TSA-100S manufactured by Espec Co., Ltd.), ET-7407 “CSP / BGA package mounting state of the Japan Electronic Machinery Manufacturers Association (EIAJ) standard by the Japan Electronics and Information Technology Industries Association (JEITA) Solder joint temperature cycle test was performed based on “Environment and durability test method”. As test conditions for this solder joint temperature cycle test, test condition B defined in Appendix 1 of ET-7407 was adopted. Specifically, −40 ° C. ± 2 ° C. was adopted as the minimum storage temperature (Tstg _min ), and 125 ° C. ± 2 ° C. was adopted as the maximum storage temperature (Tstg _max ). Further, a holding time of 30 minutes, a cycle number of 100 cycles, and a time required for temperature increase and decrease of 5 minutes were adopted. Table 1 shows the results of the solder joint temperature cycle test. In this test, the breakage rate of the second wiring pattern provided in the region between the nine drive ICs and the regions at both ends is evaluated. The regions between the drive ICs are distinguished by assigning numbers with reference to one end in the main scanning direction.

  From the test results shown in Table 1, it was found that the thermal head C can reduce the peeling of the welded part as compared with the thermal head D. Therefore, it was found that the thermal head C can improve the reliability.

  Further, from the test results shown in Table 1, it was found that the thermal heads A and B can reduce the peeling of the welded portion as compared with the thermal head D. Therefore, it was found that the thermal heads A and B can improve the reliability. Since the characteristic configuration of the thermal heads A and B can be adopted in the thermal head C, the reliability of the thermal head C can be further improved.

1 Thermal printer (recording device)
10 Thermal head (recording head)
DESCRIPTION OF SYMBOLS 11 Conveyance mechanism 111 Platen roller 112,113,114,115 Conveyance roller 12 Control mechanism 20 Head base | substrate 21 Head board | substrate 22 Thermal storage layer 22a Base part 22b Protrusion part 23 Electrical resistance layer 23a
24 conductive layer 241 first conductive layer 242 second conductive layer 243 third conductive layer (conductive layer)
243a 1st control part 243b 2nd control part 243c 3rd control part 25 Protective layer 251 1st protective layer 252 2nd protective layer 26 Control IC (control element)
30 Wiring Base 31 First Support Substrate 32 Second Support Substrate 321 Main Extension 322 Projection 33 Wiring Layer (Wiring)
331 First wiring layer (first wiring pattern)
331a First main extending portion 331b First extending portion 331b ₁ First main trunk region 331b ₂ First sub extended region 332 Second wiring layer (second wiring pattern)
332a Second main extension portion 332b Second extension portion 332b ₁ Second main trunk region 332b ₂ Second sub extension region 332b ₃ Second branch region 333 Third wiring layer 334 Fourth wiring layer 34 External connection member 40 Mounting substrate P Recording medium D1, D2 Main scanning direction D3, D4 Sub scanning direction D5, D6 Thickness direction

Claims (8)

A head substrate, a plurality of heating elements arranged along the main scanning direction on the head substrate, and a plurality of drives for controlling driving of the plurality of heating elements arranged along the main scanning direction A head base having an element and a plurality of conductive layers provided on both sides in the main scanning direction of each of the plurality of driving elements connected to the plurality of heating elements or the plurality of driving elements , And a first support substrate, a second support substrate provided so as to overlap the first support substrate, and the plurality of conductive layers provided between the first support substrate and the second support substrate. A wiring substrate having a plurality of wirings connected to
The second support substrate protrudes from the end of the first support substrate along the heat generating element side to the heat generating element side in the sub-scanning direction from the end of the first support substrate. A plurality of protrusions, and
The plurality of protrusions have an end on the heating element side in the sub-scanning direction along the main scanning direction,
The plurality of wirings have a plurality of extending portions extending to the plurality of protruding portions,
The plurality of extending portions are connected to the plurality of conductive layers along the main scanning direction.   2. The recording head according to claim 1, wherein the plurality of conductive layers have ends on the wiring substrate side extending along the main scanning direction.   3. The recording head according to claim 1, wherein a width of the plurality of protrusions along the main scanning direction becomes narrower toward the heating element side. 4. The plurality of wirings include a first wiring pattern;
4. The device according to claim 1, wherein the first wiring pattern is provided along an end of the main extending portion and the protruding portion of the second support substrate on the side of the heating element. The recording head described in 1. The plurality of wirings include a second wiring pattern;
The recording head according to claim 4, wherein the second wiring pattern is provided with an end on the heat generating element side along the first wiring pattern. The head base has a protective layer covering a part of the plurality of conductive layers,
6. The recording head according to claim 1, wherein the protective layer has an end on the wiring substrate side extending along an end on the heat generating element side of the second support substrate. .   2. The connection areas of the plurality of wirings with respect to the plurality of conductive layers are smaller at both ends of the plurality of driving elements in the main scanning direction than between the plurality of driving elements. The recording head according to claim 6.   A recording apparatus comprising: the recording head according to claim 1; and a transport unit that transports a recording medium.

Images