JP6670654B2 - Thermal head and thermal printer - Google Patents

Description

  The disclosed embodiments relate to a thermal head and a thermal printer.

  Conventionally, various thermal heads have been proposed as printing devices such as facsimile machines and video printers. For example, there is known a thermal head in which a heat generating portion and an electrode arranged on a heat storage layer are protected by a protective layer, and a part of the protective layer is covered with a resin layer (for example, see Patent Document 1).

JP-A-9-234895

  However, the conventional thermal head has room for improvement in that thermal storage properties are insufficient due to, for example, heat radiation from the resin layer, and sufficient thermal responsiveness may not be realized only by the presence of the thermal storage layer.

  One embodiment of the present invention has been made in view of the above, and an object of the present invention is to provide a thermal head and a thermal printer that can improve thermal responsiveness.

  A thermal head according to an aspect of the embodiment includes a substrate, a heating unit and an electrode, an electrical insulating layer, a protective layer, and a heat storage unit. The heat generating portion and the electrodes are provided so as to be arranged on the substrate. An electrical insulating layer is provided on the electrode. The protective layer is provided on the electric insulating layer. The heat storage unit is provided between the substrate and the protective layer and at an end of the electrical insulating layer.

  According to the thermal head of one aspect of the embodiment, the thermal responsiveness can be improved by providing the heat storage portion provided between the substrate and the protective layer and at the end of the electrical insulating layer.

FIG. 1 is an exploded perspective view schematically showing a thermal head according to the first embodiment. FIG. 2 is a plan view showing a schematic configuration of the thermal head shown in FIG. FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a plan view showing a schematic configuration near the first insulating layer. FIG. 5 is a sectional view taken along line VV of FIG. FIG. 6 is a schematic diagram illustrating the thermal printer according to the first embodiment. FIG. 7 is a view schematically showing a thermal head according to the second embodiment. FIG. 8 is a plan view illustrating a schematic configuration of the thermal head according to the third embodiment. FIG. 9 is a sectional view taken along line IX-IX of FIG. FIG. 10 is a view schematically showing a thermal head according to the fourth embodiment.

  Hereinafter, embodiments of a thermal head and a thermal printer disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited by the embodiments described below.

<First embodiment>
FIG. 1 schematically shows a configuration of the thermal head according to the first embodiment. The thermal head 1 shown in FIG. 1 includes a head base 3, a heat radiating plate 90, and an adhesive member 14.

  The head base 3 is formed in a substantially rectangular parallelepiped shape, and is placed on the heat sink 90 via the adhesive member 14. The components constituting the thermal head 1 are provided on the substrate 7 of the head base 3. The head base 3 generates heat by applying a voltage in accordance with an electric signal supplied from the outside via the connector 31. 9 is heated to print on a recording medium. Note that the members constituting the thermal head 1 will be described later with reference to FIGS. 2 and 3, and the recording medium will be described later with reference to FIG.

  The connector 31 is joined to the head base 3 by the sealing member 12, and electrically connects the outside and the head base 3. The bonding member 14 bonds the head base 3 and the heat sink 90. The heat radiating plate 90 has a rectangular parallelepiped shape, and is provided to radiate heat of the head base 3. The heat radiating plate 90 is made of, for example, a metal material such as copper, iron, or aluminum, and has a function of radiating heat that does not contribute to printing, out of the heat generated in the heat generating portion 9 of the head base 3.

  Next, each member constituting the thermal head 1 will be further described with reference to FIGS. FIG. 2 is a plan view showing a schematic configuration of the thermal head 1 shown in FIG. 1, and FIG. 3 is a sectional view taken along line III-III of FIG.

  The thermal head 1 includes a substrate 7, a heat storage layer 13, a thick film electrode 16, an electric resistance layer 15, a common electrode 17, an individual electrode 19, an IC-connector connection electrode 21, a ground electrode 4, a connection terminal 2, and an IC-IC connection electrode. 26, a drive IC 11, a first insulating layer 18, a hard coat 29, a second insulating layer 30, a protective layer 25, and a covering layer 27. In FIG. 2, illustration of the sealing member 12, the protective layer 25, and the coating layer 27 is omitted.

  The substrate 7 has a rectangular shape in plan view, and includes one long side 7a, the other long side 7b, one short side 7c, the other short side 7d, a side surface 7e, a first main surface 7f, and a second long side 7d. It has a main surface 7g. The substrate 7 is made of, for example, an electrically insulating material such as alumina ceramics or a semiconductor material such as single crystal silicon. Hereinafter, the first main surface 7f may be referred to as an “upper surface” and the second main surface 7g may be referred to as a “lower surface” for convenience of description. Similarly, the first main surface 7f side may be referred to as "up" or "upper", and the second main surface 7g side may be referred to as "lower" or "lower" with reference to the side surface 7e.

  A connector 31 is provided on the side surface 7 e of the substrate 7. The connector 31 is fixed to the side surface 7e by the connector pins 8, the conductive bonding material 23, and the sealing member 12. The conductive bonding material 23 is disposed between the connection terminal 2 and the connector pin 8, and may be, for example, a solder or an anisotropic conductive adhesive. Note that a plating layer (not shown) made of Ni, Au, or Pd may be provided between the conductive bonding material 23 and the connection terminal 2. Note that the conductive bonding material 23 is not necessarily provided.

  The connector 31 has a plurality of connector pins 8 and a housing 10 that houses the plurality of connector pins 8. One of the connector pins 8 is exposed outside the housing 10, and the other is housed inside the housing 10. The plurality of connector pins 8 are electrically connected to the connection terminals 2 of the head base 3 and are electrically connected to various electrodes of the head base 3.

  The sealing member 12 has a first sealing member 12a and a second sealing member 12b. The first sealing member 12a is located on the first principal surface 7f side of the substrate 7, and the second sealing member 12b is located on the second principal surface 7g side of the substrate 7, respectively. The first sealing member 12a is provided so as to seal the connector pin 8 and various electrodes, and the second sealing member 12b is so formed as to seal a contact portion between the connector pin 8 and the substrate 7. Is provided.

  The sealing member 12 is provided so that the connection terminals 2 and the connector pins 8 are not exposed to the outside, and is made of, for example, an epoxy-based thermosetting resin, an ultraviolet-setting resin, or a visible-light-setting resin. Can be. The first sealing member 12a and the second sealing member 12b may be made of the same material, or may be made of different materials.

  The adhesive member 14 is disposed on the heat radiating plate 90 and joins the second main surface 7 g of the substrate 7 to the heat radiating plate 90. Examples of the adhesive member 14 include a double-sided tape or a resin adhesive.

  The heat storage layer 13 is provided on the first main surface 7 f of the substrate 7. The heat storage layer 13 extends in the main scanning direction, has a substantially semi-elliptical cross section, and protrudes above the substrate 7. It is practically preferable that the heat storage layer 13 be provided at a height of, for example, 15 to 90 μm from the substrate 7.

  The heat storage layer 13 is made of a material such as glass having low thermal conductivity, and has a function of temporarily storing a part of the heat generated in the heat generating portion 9. Therefore, the heat storage layer 13 can shorten the time required for raising the temperature of the heat generating portion 9 and functions to enhance the thermal response characteristics of the thermal head 1. The heat storage layer 13 is formed, for example, by applying a predetermined glass paste obtained by mixing a suitable organic solvent to glass powder on the upper surface of the substrate 7 by screen printing or the like, and firing the same.

  The thick film electrode 16 is provided on the upper surface side of the substrate 7. The thick film electrode 16 is arranged so as to extend in the main scanning direction along one long side 7a of the substrate 7, and is provided to increase the electric capacity of the common electrode 17 provided above. .

  The electric resistance layer 15 is provided on the substrate 7 and the heat storage layer 13 so as to cover the thick film electrode 16. Various electrodes constituting the head base 3 are provided on the electric resistance layer 15. The electric resistance layer 15 is patterned in the same shape as various electrodes constituting the head base 3. Between the common electrode 17 and the individual electrode 19, there is an exposed region where the electric resistance layer 15 is exposed, and the exposed region constitutes each element of the heating section 9. The plurality of elements constituting the heat generating portion 9 are arranged on the heat storage layer 13 along the longitudinal direction of the substrate 7. The heat generating portion 9 is arranged at a predetermined interval from the short sides 7c and 7d along the short direction among the sides of the first main surface 7f of the substrate 7.

  The heat generating section 9 has a function of generating heat in accordance with an electric signal supplied from the outside, and thermally transferring ink on an ink sheet (not shown) to a recording medium (not shown). The plurality of elements constituting the heat generating portion 9 are arranged at a density of, for example, 100 dpi to 2400 dpi (dot per inch). The arrangement of the electric resistance layer 15 constituting the heating section 9 is not limited to the illustrated one, and may be provided only between the common electrode 17 and the individual electrode 19, for example.

  The heat generating portion 9 includes, for example, an electric resistance layer 15 having a relatively high electric resistance such as TaN, TaSiO, TaSiNO, TiSiO, TiSiCO or NbSiO, and a common electrode 17 made of a metal such as Al or Cu. And the individual electrodes 19. When a voltage is applied to the electric resistance layer 15 disposed between the common electrode 17 and the individual electrodes 19, the electric resistance layer 15 generates heat by Joule heating.

  The common electrode 17 includes main wiring portions 17a and 17d, a sub wiring portion 17b, and a lead portion 17c. The common electrode 17 electrically connects a plurality of elements constituting the heating section 9 and the connector 31. The main wiring portion 17 a extends along one long side 7 a of the substrate 7 and is provided on the thick film electrode 16. The main wiring portion 17a and the thick film electrode 16 are electrically connected via the electric resistance layer 15. The sub-wiring portion 17b extends along each of one short side 7c and the other short side 7d of the substrate 7. The lead portions 17c individually extend from the main wiring portion 17a toward each of the plurality of elements constituting the heat generating portion 9. The main wiring portion 17d extends along the other long side 7b of the substrate 7.

  The individual electrode 19 electrically connects the heating section 9 and the driving IC 11. Specifically, the elements constituting the heat generating section 9 are divided into a plurality of groups, and the individual electrodes 19 are assigned to each element of the heat generating section 9 constituting each group and to correspond to each group. The driving ICs 11 are electrically connected to each other. The drive IC 11 will be described later.

  The IC-connector connection electrode 21 electrically connects the drive IC 11 and the connector 31. A plurality of IC-connector connection electrodes 21 are connected to each of the drive ICs 11, and each of these IC-connector connection electrodes 21 is configured by one or a plurality of wires having different functions.

  The ground electrode 4 is surrounded by the individual electrode 19, the IC-connector connection electrode 21, and the main wiring portion 17d of the common electrode 17, and has a large area. The ground electrode 4 is maintained at a ground potential of 0 to 1V.

  The connection terminal 2 is provided on the other long side 7 b of the substrate 7, and connects the common electrode 17, the individual electrode 19, the IC-connector connection electrode 21 and the ground electrode 4 to the connector 31. The connection terminal 2 is provided so as to correspond to the connector pin 8, and when connecting the connector 31, the connector pin 8 and the connection terminal 2 are connected so as to be electrically independent from each other.

  The IC-IC connection electrode 26 electrically connects the adjacent drive ICs 11. The IC-IC connection electrodes 26 are provided so as to correspond to the IC-connector connection electrodes 21, respectively, and transmit various signals to the adjacent drive ICs 11.

  The electric resistance layer 15 and the various electrodes are formed, for example, by sequentially laminating the constituent materials on the heat storage layer 13 by, for example, a thin film forming technique such as a sputtering method. It is provided by processing into a pattern of. As described above, the various electrodes are electrically connected to the heat generating portion 9 and the thick film electrode 16, and the thickness thereof can be, for example, 0.1 to 2 μm.

  The drive IC 11 is disposed, for example, on the first main surface 7f side of the substrate 7. Further, the plurality of drive ICs 11 are arranged along the arrangement direction of the heat generating units 9 so as to correspond to the respective elements of the heat generating unit 9 assigned to each drive IC 11. The drive IC 11 is connected to the other end of the individual electrode 19 and one end of the IC-connector connection electrode 21, and individually drives each element of the heating unit 9 according to an externally supplied electric signal. Is supplied to the heat generating section 9. As the driving IC 11, for example, a switching member having a plurality of switching elements inside can be used.

  The first insulating layer 18 is provided on the main wiring portion 17 a of the common electrode 17. The first insulating layer 18 is provided so as to cover the thick film electrode 16 in a plan view, and smoothes a step caused by the thick film electrode 16.

  The hard coat 29 seals the drive IC 11 in a state where the individual electrode 19, the IC-IC connection electrode 26, and the IC-connector connection electrode 21 are connected. For example, a resin material such as an epoxy resin or a silicone resin is used. Can be used.

  The second insulating layer 30 is provided so as to be adjacent to a protective layer 25 described later, and covers a part of the individual electrode 19. More specifically, the second insulating layer 30 is provided on the other long side 7b side of the substrate 7 with respect to the protective layer 25.

  The second insulating layer 30 is provided so as to extend along the main scanning direction, and has a sub-wiring portion 17b provided along one short side 7c and a sub-wiring portion 17b provided along the other short side 7d. It is provided between the wiring portion 17b. The second insulating layer 30 is a resin such as polyimide or silicone resin, for example, and can be manufactured by printing or applying a resin material by a dispenser. The second insulating layer 30 is not limited to a resin, and may be, for example, printed and baked glass.

  The protection layer 25 is a member that is disposed on the heat storage layer 13 formed on the upper surface of the substrate 7 and covers the heating section 9, the second insulating layer 30, the common electrode 17, and the individual electrodes 19. More specifically, the protective layer 25 is provided so as to cover a part of the individual electrode 19 from the edge of the substrate 7, that is, the long side 7 a and the short sides 7 c and 7 d of the substrate 7, and the end on the side surface 7 e side. Are arranged on the second insulating layer 30.

  The coating layer 27 is provided on the substrate 7 so as to partially cover the common electrode 17, the individual electrode 19, the IC-connector connection electrode 21, and the protective layer 25. The coating layer 27 oxidizes the area covered with the common electrode 17, the individual electrode 19, the IC-IC connection electrode 26, the IC-connector connection electrode 21, and the protective layer 25 by contact with the air or is included in the air. Protects against corrosion due to moisture and the like.

  Openings (not shown) for exposing the individual electrodes 19 connected to the drive IC 11 and the IC-connector connection electrodes 21 are formed in the coating layer 27, and these wirings are driven through the openings. It is connected to IC11. The drive IC 11 is connected to the individual electrode 19 and the IC-connector connection electrode 21 in order to protect the drive IC 11 and the connection between the drive IC 11 and these electrodes. It is sealed by being covered with a hard coat 29 made of resin such as.

  Hereinafter, the thermal head 1 according to the first embodiment will be further described with reference to FIGS. FIG. 4 is a plan view showing a schematic configuration near the first insulating layer 18 arranged on the thick film electrode 16 in the thermal head 1 shown in FIG. 2, and FIG. 5 is a line V-V in FIG. It is sectional drawing. In FIG. 4, illustration of the protective layer 25 provided on the first insulating layer 18 and the covering layer 27 provided on the protective layer 25 is omitted.

  The thermal head 1 according to the embodiment includes a substrate 7, a thick film electrode 16 as an electrode, a first insulating layer 18 as an electric insulating layer, a first heat storage unit 20, and a protective layer 25.

  The thick film electrode 16 is arranged long in the main scanning direction along one long side 7 a of the substrate 7. The thick film electrode 16 is formed by, for example, printing a thick film of an Ag paste or an Au paste on the substrate 7 by a printing method. The thickness of the thick film electrode 16 can be set to, for example, 5 to 30 μm, but is gradually inclined at the end as shown in FIG.

  The first insulating layer 18 is provided so as to cover the thick film electrode 16, and is arranged along the one long side 7 a of the substrate 7 in the main scanning direction, like the thick film electrode 16. The first insulating layer 18 is an electrically insulating resin such as a polyimide or a silicone resin, and can be formed by printing or applying a resin material by a dispenser. The thickness of the first insulating layer 18 can be, for example, about 8 to 20 μm.

  The protective layer 25 is a first protective layer that covers a part of the main wiring part 17 a, a part of the sub wiring part 17 b, the lead part 17 c, the heat generating part 9, the second insulating layer 30, and a part of the individual electrode 19. It has a laminated structure including a first protective layer 25a and a second protective layer 25b provided on the first protective layer 25a.

The first protective layer 25a protects the area covered with the heat generating portion 9, the common electrode 17, and the individual electrode 19 from corrosion due to adhesion of moisture or the like contained in the air or abrasion due to contact with a recording medium to be printed. I do. The first protective layer 25a can be made of, for example, SiN, SiO ₂ , SiON, or the like. The thickness of the first protective layer 25a can be, for example, 1 to 10 μm.

  The second protective layer 25b is made of a material having higher abrasion resistance than the first protective layer 25a, and protects the heat generating portion 9 from abrasion caused by contact with a printing medium to be printed, for example. The second protective layer 25b can be made of, for example, TiN, TiCN, SiC, SiON, SiN, TaN, TaSiO, or the like. The thickness of the second protective layer 25b can be, for example, 2 to 15 μm.

  Each of the first protective layer 25a and the second protective layer 25b can be manufactured by, for example, a sputtering method or an ion plating method using an electron gun.

  The first heat storage unit 20 is provided so as to be adjacent to the end of the first insulating layer 18 on the substrate 7. The first heat storage section 20 has the same configuration as the first insulating layer 18 except that the thickness is larger than the first insulating layer 18. Specifically, the thickness of the first heat storage unit 20 is, for example, 10 to 20 μm.

  The first heat storage section 20 is provided at an end of the first insulating layer 18, particularly closer to the heating section 9 than the thick film electrode 16. Further, the first heat storage section 20 is provided on the substrate 7 having lower heat radiation than the thick film electrode 16, and is disposed between the substrate 7 and the protective layer 25. For this reason, in the first heat storage section 20, the heat storage rather than the heat radiation is superior, and as the heat storage member functions as one of the heat storage members, the heat storage of the entire thermal head 1 is enhanced. Therefore, according to the thermal head 1 according to the embodiment, the thermal responsiveness can be improved. The first heat storage unit 20 having such a configuration may be provided at the same time as the first insulating layer 18 or may be provided at a timing different from that of the first insulating layer 18.

  Further, as described above, the thickness of the first heat storage section 20 is larger than the thickness of the first insulating layer 18. For this reason, the amount of heat stored in the first heat storage unit 20 can be made larger than the amount of heat stored in the first insulating layer, and heat is not easily radiated from the first heat storage unit 20 to the first insulating layer 18. Therefore, the heat storage property of the first heat storage unit 20 can be improved, and the thermal responsiveness of the thermal head 1 can be improved. The thickness of the first heat storage section 20 and the thickness of the first insulating layer 18 can be measured by cutting the head base 3 in the thickness direction and observing a cross section. Here, the thickness of the first heat storage unit 20 is a length in a direction perpendicular to the surface of the substrate 7. The thickness of the first insulating layer 18 is a length in a direction perpendicular to the thickness of the thick film electrode 16.

  In addition, the thermal head 1 according to the embodiment further includes a cover layer 27 disposed on the protective layer 25. The coating layer 27 is in close contact with the protection layer 25 to cover the protection layer 25, thereby suppressing the occurrence of a problem that the protection layer 25 is peeled off from a protection target such as the heating section 9 or various electrodes. The coating layer 27 is made of, for example, a resin material such as an epoxy resin, a polyimide resin, or a silicone resin.

  The coating layers 27 are arranged with different thicknesses. Specifically, the coating layer 27 is arranged such that the height from the substrate 7 to the upper surface 32a of the coating layer 27 decreases from the thick film electrode 16 side toward the heat generating portion 9 side. By arranging such a coating layer 27, the height from the substrate 7 to the upper surface of the coating layer 27 at a location close to the heat generating portion 9 can be kept low. It is possible to reduce the occurrence of inconveniences.

  The thermal head 1 further includes a thin portion 33. The thin portion 33 is provided on a portion of the protective layer 25 that overlaps the first heat storage portion 20 in plan view. Further, the height of the thin portion 33 from the substrate 7 to the upper surface 32b of the thin portion 33 is lower than the height from the substrate 7 to the upper surface 32a of the covering layer 27 at a portion farther from the heat generating portion 9 than the thin portion 33. It is configured as follows. The thin portion 33 is arranged so that the height from the substrate 7 to the upper surface 32b of the thin portion 33 decreases from the thick film electrode 16 side toward the heat generating portion 9 side.

  By configuring the thin portion 33 in this manner, the height from the substrate 7 to the upper surface 32b of the thin portion 33 in a portion close to the heat generating portion 9 can be suppressed to a low level. Occurrence can be further reduced. Here, the thin portion 33 is made of, for example, the same material as the coating layer 27 and can form a part of the coating layer 27.

  In addition, the thermal head 1 further includes a second heat storage unit 34. The second heat storage section 34 is provided on the protective layer 25 and on a portion overlapping the first heat storage section 20 in a plan view, that is, on a side closer to the heating section 9 than the thin section 33. Further, the second heat storage section 34 is configured such that the height from the substrate 7 to the upper surface 32c of the second heat storage section 34 is lower than the height from the substrate 7 to the upper surface 32b of the thin portion 33. The second heat storage section 34 is arranged such that the height from the substrate 7 to the upper surface 32b of the thin section 33 decreases from the thick film electrode 16 side to the heat generation section 9 side.

  By configuring the second heat storage unit 34 in this manner, the height from the substrate 7 to the upper surface 32c of the second heat storage unit 34 at a position closer to the heat generating unit 9 than the thin-walled portion 33 can be suppressed, and therefore, the recording medium Can be further reduced.

  The second heat storage unit 34 is made of, for example, the same material as the coating layer 27, and can form a part of the coating layer 27. Thereby, the second heat storage unit 34 can be configured without adding a new material.

  As described above, the second heat storage section 34 is provided at a position closer to the heat generating section 9 than the thin section 33, and the heat generated in the heat generating section 9 is transferred to the second heat storage section 34 before the thin section 33. Is transmitted. In addition, the thin portion 33 has a relatively small area facing the second heat storage portion 34, and the heat stored in the second heat storage portion 34 is not easily radiated from the thin portion 33. For this reason, the heat that has reached the second heat storage unit 34 temporarily stays in the second heat storage unit 34, and the heat storage performance of the entire thermal head 1 is enhanced. Therefore, according to the thermal head 1 according to the present embodiment, the thermal responsiveness can be further improved.

  Further, the first heat storage section 20 is arranged so as not to overlap with the thick film electrode 16 in plan view. In other words, the first heat storage section 20 is not formed on the thick film electrode 16. Therefore, according to the thermal head 1 according to the present embodiment, the heat stored in the first heat storage unit 20 is less likely to be dissipated through the thick film electrode 16, and the heat storage property of the first heat storage unit 20 can be maintained. .

  Next, a thermal printer according to the first embodiment will be described with reference to FIG. FIG. 6 is a schematic diagram illustrating the thermal printer 100 according to the first embodiment.

  The thermal printer 100 shown in FIG. 6 includes the above-described thermal head 1, a transport mechanism 40, a platen roller 50, a power supply device 60, and a control device 70. The thermal head 1 is mounted on a mounting surface 80a of a mounting member 80 provided on a housing (not shown) of the thermal printer 100. The thermal head 1 is mounted on the mounting member 80 along a main scanning direction orthogonal to the transport direction S.

  The transport mechanism 40 includes a drive unit (not shown) and transport rollers 43, 45, 47, and 49. The transport mechanism 40 is disposed on the protective layer 25 disposed on the heat generating portion 9 of the thermal head 1 so that the recording medium P such as thermal paper or image receiving paper to which ink is transferred is along the transport direction S indicated by an arrow. Transport. The drive unit has a function of driving the transport rollers 43, 45, 47, and 49, and may use, for example, a motor. The transport rollers 43, 45, 47, and 49 include, for example, cylindrical shafts 43a, 45a, 47a, and 49a made of metal such as stainless steel and elastic members 43b, 45b, and 47b made of butadiene rubber or the like. 49b. When the recording medium P is, for example, an image receiving paper to which ink is transferred, an ink film (not shown) may be transported together with the recording medium P between the recording medium P and the heating section 9 of the thermal head 1.

  The platen roller 50 has a function of pressing the recording medium P onto the protective layer 25 located on the heating section 9 of the thermal head 1. The platen roller 50 is disposed so as to extend along a direction orthogonal to the transport direction S, and both ends are supported and fixed so that the platen roller 50 can rotate while pressing the recording medium P on the heat generating unit 9. The platen roller 50 may be, for example, a cylindrical shaft body 50a made of metal such as stainless steel covered with an elastic member 50b made of butadiene rubber or the like.

  The power supply device 60 has a function of supplying a current for causing the heat generating portion 9 of the thermal head 1 to generate heat and a current for operating the drive IC 11 as described above. The control device 70 has a function of supplying a control signal for controlling the operation of the drive IC 11 to the drive IC 11 in order to selectively heat the heat generating portion 9 of the thermal head 1 as described above.

  The thermal printer 100 presses the recording medium P onto the heat generating portion 9 of the thermal head 1 by the platen roller 50, and conveys the recording medium P onto the heat generating portion 9 by the transport mechanism 40. By causing the heat generating section 9 to selectively generate heat, predetermined printing is performed on the recording medium P. When the recording medium P is an image receiving paper or the like, printing on the recording medium P is performed by thermally transferring the ink of an ink film (not shown) conveyed together with the recording medium P onto the recording medium P.

<Second embodiment>
Next, a thermal head 1A according to a second embodiment will be described with reference to FIG. FIG. 7 is a view schematically showing a thermal head 1A according to the second embodiment. A thermal head 1A shown in FIG. 7 corresponds to a thermal head 1 according to the first embodiment shown in FIG.

  The thermal head 1A shown in FIG. 7 has the same configuration as the thermal head 1 according to the first embodiment, except that the thermal head 1A includes a first heat storage unit 20a instead of the first heat storage unit 20.

  The first heat storage unit 20a can be made of, for example, the same material as the heat storage layer 13, for example, glass having low thermal conductivity. For this reason, according to the thermal head 1A according to the second embodiment, the performance of the first insulating layer 18 is not necessarily required for the first heat storage section 20a. The degree of freedom is improved.

<Third embodiment>
Next, a thermal head 1B according to a third embodiment will be described with reference to FIGS. FIG. 8 is a plan view showing a schematic configuration of a thermal head 1B according to the third embodiment, and FIG. 9 is a sectional view taken along line IX-IX of FIG. In FIG. 8, illustration of the protective layer 25 and the covering layer 27 is omitted.

  The thermal head 1B shown in FIGS. 8 and 9 has the same configuration as the thermal head 1 according to the first embodiment, except that the thermal head 1B includes a first heat storage unit 20b instead of the first heat storage unit 20.

  The first heat storage section 20b is arranged along one long side 7a of the substrate 7 in that it is provided so as to face each element constituting the heating section 9 among the ends of the first insulating layer 18. This is different from the first heat storage unit 20. Since the first heat storage sections 20b are provided to face the heat generating sections 9, respectively, the heat stored in the first heat storage sections 20b can improve the thermal responsiveness of the corresponding heat generating sections 9 respectively. . The first heat storage section 20b may be made of the same material as the first insulating layer 18, or may be made of a different material.

<Fourth embodiment>
Next, a thermal head 1C according to a fourth embodiment will be described with reference to FIG. FIG. 10 is a diagram schematically illustrating a thermal head 1C according to the fourth embodiment. A thermal head 1C shown in FIG. 10 corresponds to a thermal head 1 according to the first embodiment shown in FIG.

  The thermal head 1C shown in FIG. 10 has the same configuration as the thermal head 1 according to the first embodiment, except that the thermal head 1C includes a first heat storage unit 20c instead of the first heat storage unit 20.

  The first heat storage section 20c is arranged not on the substrate 7 but on the first insulating layer 18. When the heat dissipation of the first insulating layer 18 is lower than that of the substrate 7, the heat dissipation from the first heat storage unit 20c can be suppressed, and the thermal responsiveness can be further improved.

  The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention. For example, the thermal printer 100 using the thermal head 1 according to the first embodiment has been described. However, the present invention is not limited to this, and the thermal heads 1A to 1C according to each embodiment may be used for the thermal printer 100. Good. Further, the thermal heads 1 to 1C according to a plurality of embodiments may be combined.

  Further, for example, a thin film head having a thin heating section 9 by forming the electric resistance layer 15 as a thin film has been described as an example. However, the present invention is not limited to this. After patterning the various electrodes, a thick film head having a thick heating section 9 may be applied by forming a thick electric resistance layer 15.

  Further, although a flat head in which the heat generating portion 9 is formed on the first main surface 7f of the substrate 7 has been described as an example, an end surface head in which the heat generating portion 9 is provided on an end surface of the substrate 7 may be used.

  Note that the sealing member 12 may be formed of the same material as the hard coat 29 that covers the drive IC 11. In this case, when printing the hard coat 29, the hard coat 29 and the sealing member 12 may be formed at the same time by printing also on the region where the sealing member 12 is formed.

  Further, in the above-described embodiment, the protective layer 25 is described as having a two-layer structure. However, the present invention is not limited to this, and the protective layer 25 may be formed of a single layer or three or more layers.

  In the above-described embodiment, the thin portion 33 and the second heat storage portion 34 have been described as being made of the same material as the coating layer 27. However, the present invention is not limited to this. You may.

  Further, in the above-described embodiment, the first heat storage units 20 to 20c are described as being provided on the end of the first insulating layer 18 that is closer to the heat generation unit 9, but the present invention is not limited to this. It may be arranged over the entire end of the insulating layer 18.

  In the above-described embodiment, the first heat storage units 20 to 20c have been described as being arranged so as not to overlap with the thick film electrode 16 in a plan view, but a part of the first heat storage units 20 to 20c is It may be arranged so as to overlap with the thick film electrode 16 in plan view.

  Further effects and modifications can be easily derived by those skilled in the art. For this reason, the broader aspects of the present invention are not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof.

1, 1A, 1B, 1C Thermal head 7 Substrate 9 Heating section 16 Thick film electrode (electrode)
18 First insulating layer (electrical insulating layer)
20, 20a, 20b, 20c First thermal storage section 25 Protective layer 25a First protective layer 25b Second protective layer 27 Coating layer 33 Thin section 34 Second thermal storage section 100 Thermal printer

Claims (10)

Board and
A heating unit and an electrode provided on the substrate,
An electrical insulating layer provided on the electrode,
A protective layer provided on the heating section and on the electrical insulating layer;
A first heat storage unit provided between the substrate and the protective layer and provided at an end of the electrical insulating layer;
Equipped with a,
Wherein the first thermal storage unit, a thermal head, wherein Rukoto disposed without overlapping the said electrode in plan view. Board and
A heating unit and an electrode provided on the substrate,
An electrical insulating layer provided on the electrode,
A protective layer provided on the heating section and on the electrical insulating layer;
A coating layer provided on the protective layer ,
A first heat storage unit provided between the substrate and the protective layer and provided at an end of the electrical insulating layer;
Bei to give a,
The height from the substrate to the upper surface of the coating layer, characterized and to salicylate Maruheddo to become smaller toward the heat-generating portion side from the electrode side. 3. The thermal head according to claim 2 , wherein the coating layer further includes a second heat storage unit provided closer to the heat generation unit than a portion overlapping the first heat storage unit in a plan view. 4. The thermal head according to claim 3 , wherein the second heat storage unit is made of the same material as the covering layer. The thermal head according to any one of claims 2 to 4 , wherein the coating layer further includes a thin portion provided in a portion overlapping the first heat storage portion in plan view. The thermal head according to any one of claims 2 to 5 , wherein the first heat storage unit is arranged so as not to overlap with the electrode in plan view. The thermal head according to any one of claims 1 to 6 , wherein a thickness of the first heat storage unit is larger than a thickness of the electric insulating layer. The thermal head according to any one of claims 1 to 7 , wherein the first heat storage section is provided at an end of the electrical insulating layer closer to the heating section. The thermal head according to any one of claims 1 to 8, wherein the first heat storage unit is made of the same material as the electric insulating layer. A thermal head according to any one of claims 1 to 9,
A transport mechanism for transporting the recording medium onto the heating unit,
And a platen roller for pressing the recording medium on the heating section.

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