JP2016215417A - Thermal print head and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal print head for allowing efficient formation of a protective layer covering heating sections without causing failures such as damage and disconnection of an electrode layer in manufacturing of the thermal print head and a method for manufacturing the thermal print head.SOLUTION: A thermal print head 10A includes: a substrate 100; a plurality of heating sections arranged in a longitudinal direction of the substrate to be closer to one side in a transverse direction on the substrate 100; a conductor connected to each heating section; and a protective layer 150 for covering at least the plurality of heating sections. In the substrate 100, a girder section 400 having a prescribed thickness is formed. A prescribed region on the one side in the transverse direction of the substrate 100 in the girder section 400 is covered with the protective layer 150. A region located on the other side in the transverse direction of the substrate in the girder section 400 across a boundary 402 between the region and the region covered with the protective layer 150 is not covered with the protective layer 150.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a thermal print head and a manufacturing method thereof.

  In the manufacture of a so-called thin film type thermal print head, when a protective layer covering the heat generating portion is formed after the heat generating portion is formed, for example, as shown in FIG. 11 and FIG. Sputtering or a CVD method may be applied in a state where the substrates are overlapped while exposing their heating portions. In such a method for forming a protective layer, since the substrate on which the upper layer is overlapped can be conveniently masked in the lower substrate, the material for the protective layer can be saved. At the same time, the production efficiency can be increased.

  However, when such a method for forming a protective layer is employed, if a projection such as a burr exists on the back surface of the substrate, a fine electrode layer on the substrate located below the substrate may be damaged or disconnected.

JP 2006-56046 A

  The present invention has been conceived under the circumstances described above, and in the manufacture of a thin-film thermal print head, the efficient formation of a protective layer covering the heat generating portion, such as damage to the electrode layer and disconnection. It is an object of the present invention to provide a technique that can be performed without causing a defect.

  In order to solve the above problems, the present invention employs the following technical means.

  The thermal print head provided by the first aspect of the present invention includes a substrate, a plurality of heat generating portions arranged in the longitudinal direction of the substrate closer to one side in the short direction on the substrate, and a conductor connected to each heat generating portion, A thermal print head comprising at least a protective layer that covers the plurality of heat generating portions, wherein the substrate has a girder portion having a predetermined thickness, and the girder portion has a predetermined region on one side in the short side direction of the substrate. Is covered with the protective layer, and the region located on the other side in the short direction of the substrate in the girder across the boundary to the region covered with the protective layer is not covered with the protective layer It is characterized by that.

  In a preferred embodiment, the conductor includes a signal conductor extending from each of the heat generating portions to the other side in the short direction of the substrate.

  In a preferred embodiment, the beam portion is formed in a region avoiding the signal conductor on the other side in the short direction of the substrate than the heat generating portions.

  In a preferred embodiment, the girders include those formed at both longitudinal ends of the substrate.

  In a preferred embodiment, the girder is formed by printing and baking a predetermined paste material.

  In a preferred embodiment, the paste material is a glass-based paste material.

  In a preferred embodiment, the signal conductor is formed on a base layer formed on the substrate, and the beam portion is formed of the same material as the base layer.

  In a preferred embodiment, the girder is formed with the same thickness as the underlayer.

  In a preferred embodiment, the base layer is formed in a lower layer on the other side in the short side direction of the substrate of the signal conductor, and an edge on one side in the short side direction of the substrate of the base layer is formed on the girder. It is located on the other side in the short direction of the substrate from the boundary in the part.

  In a preferred embodiment, the beam portion is independent of the base layer.

  In a preferred embodiment, the beam portion is continuous with the base layer.

  In a preferred embodiment, the beam portion is rectangular in plan view.

  In a preferred embodiment, the beam portion is circular in plan view.

  In a preferred embodiment, the signal conductor is formed on a base layer formed on the substrate, and the girder is formed so as to overlap the base layer.

  In a preferred embodiment, the girder is formed by an attachment to the substrate.

  In preferable embodiment, the said sticking thing is a tape.

  The method for manufacturing a thermal printhead provided by the first aspect of the present invention is connected to a substrate, a plurality of heat generating portions arranged in the longitudinal direction of the substrate closer to one side in the short direction on the substrate, and each heat generating portion. A method of manufacturing a thermal print head comprising a conductor and a protective layer covering at least the plurality of heat generating portions, wherein the plurality of heat generating portions and the plurality of substrate intermediates after the formation of the conductors When the protective layer is formed by laminating and holding the substrate in the short direction so that the portion faces, and applying sputtering or CVD method, the substrate intermediate is formed with a girder having a predetermined thickness. And a plurality of edges of one side in the short direction of the substrate intermediate are positioned at a middle portion in the short direction of the substrate of the spar in the lower substrate intermediate on which the substrate intermediate is stacked. Characterized by holding a stack of the substrate intermediate.

  In a preferred embodiment, the conductor includes a signal conductor extending from each of the heat generating portions to the other side in the short direction of the substrate.

  In a preferred embodiment, the girder is formed in a region avoiding the signal system conductor lead on the other side in the short direction of the substrate than the heat generating portions.

  In a preferred embodiment, the girders include those formed at both longitudinal ends of the substrate.

  In a preferred embodiment, the girder is formed by printing and baking a predetermined paste material.

  In a preferred embodiment, the paste material is a glass-based paste material.

  In a preferred embodiment, the signal conductor is formed on a base layer formed on the substrate, and the beam portion is formed of the same material as the base layer.

  In a preferred embodiment, the girder is formed at the same thickness as the underlayer.

  In a preferred embodiment, the base layer is formed in a lower layer on the other side in the short side direction of the substrate of the signal conductor, and an edge on one side in the short side direction of the substrate of the base layer is formed on the girder. It is located on the other side in the short direction of the substrate from the boundary in the part.

  In a preferred embodiment, the beam portion is independent of the base layer.

  In a preferred embodiment, the beam portion is continuous with the base layer.

  In a preferred embodiment, the beam portion is rectangular in plan view.

  In a preferred embodiment, the beam portion is circular in plan view.

  In a preferred embodiment, the signal conductor is formed on a base layer formed on the substrate, and the girder is formed so as to overlap the base layer.

  In a preferred embodiment, the girder is formed by an attachment to the substrate.

  In preferable embodiment, the said sticking thing is a tape.

  In preferable embodiment, the said sticking thing is removed after formation of the said protective layer.

  According to such a configuration, since the edge on one side of the upper substrate intermediate is always placed on the girder provided in the lower substrate intermediate, the shorter direction of the upper substrate intermediate is assumed. Even if a burr protrudes from the lower surface of the edge on one side, the burr is prevented from contacting the upper surface of the underlying substrate intermediate. Therefore, when a protective layer is formed by sputtering or CVD in a state where a plurality of substrate intermediates are stacked while being shifted in the short side direction while exposing their heating portions, they are generated in the upper substrate intermediate. The occurrence of inconvenience such as breakage or disconnection of the signal conductor on the substrate intermediate body in which the burrs are lower can be eliminated.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the drawings.

1 is an overall schematic plan view of a thermal print head according to a first embodiment of the present invention. FIG. 2 is an enlarged partial plan view of the thermal print head shown in FIG. 1. FIG. 3 is a cut end view taken along line III-III in FIG. 2. FIG. 4 is a cut end view taken along line IV-IV in FIG. 2. It is a figure explaining the manufacturing process of a head board | substrate in the part corresponded in the cutting end surface in alignment with the III-III line of FIG. It is a figure explaining the manufacturing process of a head board | substrate in the part corresponded in the cut end surface in alignment with the IV-IV line | wire of FIG. It is explanatory drawing of the aspect of the burr | flash formed in the back surface edge part of a head substrate. FIG. 7 is a diagram illustrating a manufacturing process of the head substrate subsequent to FIG. 6, and the head substrate is indicated by an end surface corresponding to a cutting end surface along line IV-IV in FIG. 2. FIG. 6 is a diagram illustrating a manufacturing process of the head substrate subsequent to FIG. 5, and the head substrate is indicated by an end surface corresponding to a cut end surface along the line III-III in FIG. 2. FIG. 9 is a diagram illustrating a manufacturing process of the head substrate subsequent to FIG. 8, and the head substrate is indicated by an end surface corresponding to a cut end surface along the line IV-IV in FIG. 2. FIG. 10 is a diagram illustrating a manufacturing process of the head substrate subsequent to FIG. 9, and the head substrate is shown by an end surface corresponding to a cross section taken along line III-III in FIG. 2. It is an enlarged partial top view of the thermal print head concerning a 2nd embodiment of the present invention. FIG. 13 is a cut end view taken along line XIII-XIII in FIG. 12. FIG. 6 is an enlarged partial plan view of a thermal print head according to a third embodiment of the present invention. FIG. 15 is a cut end view taken along line XV-XV in FIG. 14. FIG. 15 is a cut end view taken along line XVI-XVI in FIG. 14. FIG. 14 is a cut end view of a thermal print head according to a fourth embodiment of the present invention, corresponding to FIG. 13 for the second embodiment.

  Hereinafter, preferred embodiments of the present invention will be specifically described with reference to the drawings.

  1 to 11 show a thermal print head 10A according to a first embodiment of the present invention. As shown in FIGS. 1 to 4, the thermal print head 10 </ b> A includes a head substrate 100, a circuit board 300, and a heat sink 500 on which these are mounted below the head substrate 100 and the circuit board 300. The head substrate 100 includes a plurality of heat generating portions 110 arranged in the longitudinal direction of the head substrate 100 toward one side in the short direction, a conductor 200 connected to each heat generating portion 110, and a protective layer 150 covering at least the plurality of heat generating portions 110. , Basically. A driving IC is mounted on the circuit board 300.

  The head substrate 100 has at least an upper surface (main surface) 100a having an insulating property, and is formed of alumina ceramic, for example. The head substrate 100 is also rectangular in plan view and has a predetermined thickness. The head substrate 100 is obtained by forming the heat generating portion 110, the lead conductor 200, and the like in each unit substrate region in a collective substrate state, and then dividing the unit substrate into unit substrates through laser scribing, for example.

  The head substrate 100 is configured for a thermal print head classified into a so-called thin film type, and the configuration will be specifically described below.

  A partial glaze 130 is formed on one side of the main surface 100a of the head substrate 100 toward the short side (upward in FIG. 2, left in FIGS. 3 and 4). As shown in FIG. 3, the partial glaze 130 has a shape that protrudes gently in a cross section, and extends linearly so as to be parallel to the edge 100 b on one side in the short direction of the head substrate 100. ing. The partial glaze 130 is formed by printing and baking a glass-based paste. The width of the partial glaze 130 in the short side direction (sub-scanning direction) of the substrate is, for example, 500 to 700 μm, and the height of the top is, for example, 18 to 50 μm.

On the upper surface of the partial glaze 130, a plurality of heat generating portions 110 arranged in a straight line in the extending direction of the partial glaze 130 are formed. In the heat generating part 110, the resistor 220 is formed in layers on the head substrate 100 including the partial glaze 130, and the conductor 200 is layered so that the resistor 220 is exposed in a region having a predetermined width at the top of the partial glaze 130. It is formed by stacking. The resistor 200 is made of, for example, TaSiO ₂ or TaN, and is formed to a thickness of, for example, 300 to 2000 mm by sputtering or a CVD method. The conductor 200 is made of, for example, Al, and is formed with a thickness of, for example, 0.3 to 0.8 μm by sputtering or CVD. As the conductor 200, a Ta layer may be formed as a thin film under the Al layer. In the case of the present embodiment, the conductor 200 includes a common conductor 202 extending in a comb shape from one side in the short direction of the head substrate 100 and having a tip on the partial glaze 130, and from the other side in the short direction of the head substrate 100. Each of the signal conductors 201 extends separately and has a distal end facing the distal end of each common conductor 202 on the partial glaze 130. The common conductor 202 is commonly connected to the common electrode pattern 202a. Each signal conductor 201 has a terminal portion 201a on the other side in the short side of the head substrate 100, and a wire bonding pad 212 is formed on the terminal portion 201a. The patterning performed on the resistor layer 220 and each conductor layer 210 to form the common conductor 202, the signal conductor 201, and each heat generating portion 110 is performed on the resistor layer 220 laminated on the head substrate 100 and This can be performed by etching the conductor layer 210 by photolithography.

  A portion 201 b on the other side in the short side direction of the head substrate 100 of each signal conductor 201 is formed on the base layer 140 formed on the head substrate 100. The foundation layer 140 is formed to a thickness of 2 to 100 μm, for example, by printing and baking a glass paste, for example. The wire bonding pad 212 is positioned on the base layer 140, whereby the wire bonding to the pad 212 can be appropriately performed. In the present embodiment, the edge 140a on one side in the short direction of the head substrate 100 of the base layer 140 extends in the longitudinal direction of the head substrate 100 and is positioned away from the partial glaze 130. Yes.

  A girder 400 is formed at a predetermined position on the head substrate 100 where the signal conductor 201 does not exist. The girder 400 is formed simultaneously with the formation of the base layer 140. Therefore, the girder 400 is formed to have the same thickness (for example, 2 to 100 μm) as the thickness of the foundation layer 140 by printing and baking the same glass paste as that of the foundation layer 140. In the present embodiment, the beam portion 400 is independently provided at a position separated from the base layer 140. The plan view shape of the girder 400 is rectangular in this embodiment, but is not limited to this. It may have any planar shape such as a circle or a triangle. Further, in this embodiment, the girder 400 is formed at two positions on both ends in the longitudinal direction of the head substrate 100, but the number of the girder 400 is not limited. The position of the girder 400 in the short direction of the head substrate 100 is such that the edge 400a on one side in the short direction is shifted to the one side in the short direction of the head substrate 100 from the edge 140a of the base layer 140. It is necessary to be.

  The protective layer 150 is formed to a thickness of, for example, 2 to 8 μm by sputtering or CVD using, for example, SiN or SiC as a material by a method described later. In this embodiment, the protective layer 150 covers a region having a predetermined width from the edge 100b on one side in the short direction of the head substrate 100 to the other side in the short direction over the entire length in the longitudinal direction of the head substrate 100, The common conductor 202 and the signal conductor 201 are protected. An edge 150b of the protective layer 150 on the other side in the short side direction of the head substrate 100 extends linearly in the longitudinal direction of the head substrate 100 and crosses the beam portion 400 in the longitudinal direction of the head substrate 100. The base layer 140 is shifted from the edge 140a to the one side in the short direction of the head substrate 100.

  Therefore, as clearly shown in FIG. 4, the region on one side in the short side direction of the head substrate 100 in the beam portion 400 is covered with the protective layer 150, and the boundary 402 is defined with respect to the region covered with the protective layer 150. A region on the opposite side (the other side in the short side direction of the head substrate 100) is not covered with the protective layer 150. Further, a portion of the signal conductor 201 formed on the base layer 140 is not covered with the protective layer 150, and thus the wire bonding pad 212 is exposed.

  The head substrate 100 configured as described above is overlaid and fixed on the heat radiating plate 500, and the circuit substrate 300 on which the driving IC 310 is mounted is adjacent to the head substrate 100. Fixed. Bonding wires 320 connect between the driving IC 310 and the wire bonding pads 212 of the signal conductor 201 and between the driving IC 310 and appropriate positions on the circuit board 300. Further, the appropriate position of the common electrode pattern 202a and the appropriate position on the circuit board 300 are also connected by a bonding wire (not shown). The driving IC 310 and the bonding wire 320 connected to the driving IC 310 are covered with, for example, an epoxy-based protective resin 330.

  When energization of the selected signal conductor 201 is turned on by a control signal input to the drive IC 310, the resistance exposed between the signal conductor 201 and the common conductor 202 facing the partial glaze 130. The temperature of the body (heat generating part 110) is selectively raised, whereby a heat-sensitive recording medium (not shown) that contacts the top area of the partial glaze 130 develops color or the sublimation ink of the ink ribbon is applied to the recording paper. The image is transferred and printed.

  Next, the manufacturing process of the head substrate 100 configured as described above will be described with reference to FIGS. 5, 6, and 8 to 11. 5, 9, and 11, the head substrate 100 is shown by an end surface corresponding to a cut end surface along the line III-III in FIG. 2. In FIGS. 6, 8, and 10, the head substrate 100 is It is shown by an end face corresponding to a cut end face along line IV-IV in FIG.

  As shown in FIG. 5A, a partial glaze 130 is formed on the upper surface of the head substrate 100 closer to one side in the short direction by printing and baking. For forming the partial glaze 130, for example, a glass-based paste is used as described above.

  Next, as shown in FIGS. 5B and 6B, the base layer 140 is formed on the upper surface of the head substrate 100 near the other side in the short side direction, and the girder portions 400 are disposed at both longitudinal ends of the head substrate 100. Are formed by printing and baking. The underlayer 140 and the girder 400 are simultaneously formed using the same glass paste. As the glass paste for forming the underlayer 140 and the girder part 400, a glass paste having a softening point temperature lower than that of the glass paste used for forming the partial glaze 130 is used.

Next, as shown in FIGS. 5C and 6C, the resistor layer 220 is formed to a thickness of, for example, 300 to 2000 mm by sputtering or CVD using TaSiO ₂ or TaN as a material. .

  Next, as shown in FIGS. 5D and 6D, the conductor layer 210 is formed to a thickness of, for example, 0.3 to 0.8 μm by sputtering using Al or CVD. Prior to the formation of the Al layer, a thin film layer of Ta having a thickness of 0.1 μm or less can be formed.

  Next, as shown in FIG. 5E, by performing a predetermined etching process using a photolithography method on the resistor layer 220 and the conductor layer 210, the patterned common conductor 202 and signal conductor 201 are changed. Form. The signal conductors 201 thus formed are separated from one another adjacent to the longitudinal direction of the head substrate 100, and the resistor layer 130 is exposed between the tip of each signal conductor 201 and the common conductor 202. Be made. The resistor layer 220 thus exposed forms the heat generating portion 110. In the present embodiment, as shown in FIG. 6E, the resistor layer 220 and the upper conductor layer 210 are left on the upper surface of the beam portion 400. However, the present invention is not limited to this, and the resistor layer 220 is not limited thereto. The conductor layer 210 may be removed by etching.

  The above steps are performed on a collective substrate (not shown) in which a plurality of rows and a plurality of columns of unit substrate regions are formed. A cut groove is formed on the collective substrate by, for example, a laser scribing method. Thus, each unit head substrate 100 is obtained by dividing the aggregate substrate.

  The laser scribing method is performed by intermittently irradiating a high-power laser while moving the laser spot along the line to be cut from the back side of the collective substrate. As shown in FIG. 7, on the back surface peripheral portion of the unit head substrate 100 scribed and divided by this method, a ceramic material melted by high heat is raised and solidified, and is several μm (for example, 2 μm) or less. A sharp protrusion 120 (burr) may be generated.

  The formation of the protective layer 150 on the head substrate 100 divided as described above is performed as follows.

  First, as shown in FIGS. 8 and 9, the plurality of head substrates 100 are preliminarily arranged in the short side direction in which the upper surface predetermined width region on one side in the short side direction, that is, the partial glaze 130 and the heat generating portion 110 are formed. The stacked layers are held while being shifted so that the width region is exposed. At this time, as shown in FIG. 8, the edge 100 b on one side in the short direction of the lower surface of the upper head substrate 100 is positioned on the beam portion 400 of the lower head substrate 100. That is, the edge 100 b of the upper head substrate 100 is placed on the middle portion of the beam portion 400 of the lower head substrate 100. In this state, the thickness of the beam portion 400 is, for example, 2 to 100 μm as described above. Therefore, even if the upper head substrate 100 has a protrusion (burr) 120 on the back surface, the protrusion (burr) 120 protrudes. As long as the amount is equal to or less than the thickness of the beam portion 400, the protrusion (burr) 120 does not contact the signal conductor 201 on the upper surface of the lower head substrate 100, and the signal conductor 201 is damaged or disconnected. No fault can occur.

  More specifically, the protrusion (burr) 120 is generated only in the longitudinal direction intermediate portion of the head substrate 100 at the edge 100 b of the back surface of the upper head substrate 100, and the protrusion is formed on a portion of the lower head substrate 100 on the beam portion 400. Even when the (burr) 120 is not generated, the protrusion (burr) 120 of the upper head substrate 100 is the lower head substrate as long as the thickness of the beam portion 400 exceeds the protrusion amount of the protrusion (burr) 120. There is no contact with 100 signal conductors 201 and no damage or disconnection.

  If the protrusions (burrs) 120 are formed on the back surface side of the edge 100 b of the upper head substrate 100 and are placed on the beam part 400, the protrusions of the protrusions (burrs) 120 are further higher. Since the head substrate 100 can be moved away from the lower head substrate 100, the protrusion (burr) 120 of the upper head substrate 100 does not contact the signal conductor 201 of the lower head substrate 100. The possibility of damaging or disconnecting 201 is reduced.

  Next, as shown in FIGS. 10 and 11, a protective layer 150 is collectively formed in a predetermined width region of the head substrate 100 including the heat generating portions 110 in the plurality of head substrates 100 by sputtering or CVD, The head substrate 100 shown in FIGS. 1 to 4 and configured as described above is obtained.

  In such a method for forming the protective layer 150, the upper head substrate 100 can conveniently mask a region in the lower head substrate 100 where the protective layer 150 does not need to be formed. This makes it possible to efficiently form the protective layer 150 without the need for a separate mask and while saving the material for forming the protective layer 150, and as described above, the laser scribing method. While adopting an advanced and efficient substrate dividing method using a substrate, a fine pattern formed on the surface of the head substrate 100 by protrusions (burrs) 120 that can be generated around the back surface of the head substrate 100 by such a substrate dividing method. It is possible to avoid the occurrence of a problem that the signal conductor 201 having a wide width is damaged or disconnected.

  In this embodiment, since the girder part 400 is formed simultaneously with the base layer 140, a separate process for providing the girder part is not necessary.

  12 and 13 show a thermal print head 10B according to a second embodiment of the present invention. In these drawings, the same or similar members or parts as those of the thermal print head 10A according to the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  The girder portion 400 provided on the head substrate 100 of the thermal print head 10B according to the present embodiment has a form extending integrally from the base layer 140. That is, a peninsula is integrally extended from both end portions of the base layer 140 formed extending in the longitudinal direction of the head substrate 100 below the signal conductor 201 to a region where the signal conductor 201 is not formed, and the front end plan view is rectangular. The girders 400 are provided. The edge 400 (the end on one side in the short direction of the head substrate 100) 400a of the girder 400 is positioned so as to be shifted to the one side in the short direction of the head substrate 100 with respect to the edge 140a of the base layer 140. ing. Also in this embodiment, the region on one side in the short direction of the head substrate 100 in the beam portion 400 is covered with the protective layer 150, and the opposite side of the region covered with the protective layer 150 with the boundary 402 interposed therebetween. The region on the other side in the short direction of the head substrate 100 is not covered with the protective layer 150. In addition, a portion of the signal electrode layer 201 formed on the base layer 140 is not covered with the protective layer 150, and the wire bonding pad 212 is exposed. In the present embodiment, the girder 400 is integrally formed with the base layer 140, so that it is naturally formed simultaneously with the base layer 140. Further, the shape of the tip of the girder 400 is not limited to a rectangle, and may be any shape such as an arc.

  The formation of the protective layer 150 on the head substrate 100 is performed in the same manner as described above with reference to FIGS. 12 and 13, the position of the boundary 402 indicates the position of the edge 100 b of the head substrate 100 that is stacked above the head substrate 100 when the protective layer 150 is formed.

  It will be apparent that the head substrate 100 according to this embodiment can enjoy the same advantages as those described above for the first embodiment.

  14, 15, and 16 show a thermal print head 10C according to a third embodiment of the present invention. In these drawings, the same or similar members or parts as those of the thermal print head 10A according to the first embodiment shown in FIGS. 1 to 4 are denoted by the same reference numerals and detailed description thereof is omitted. To do.

  The girder part 400 provided on the head substrate 100 of the thermal print head 10C according to the present embodiment is provided with a thickness of, for example, 2 to 100 μm by printing and baking a glass-based paste on the base layer 140. The plan view shape of the beam portion 400 is a rectangle. For forming the girder 400, a glass paste having a softening point lower than that of the glass paste used for forming the underlayer 140 is used. The underlayer 140 is formed to have a thickness of, for example, 2 to 100 μm below the signal conductor 201. In the present embodiment, the edge 140a on one side in the short side direction of the head substrate 100 is formed with respect to the partial glaze 130. The end portions in the longitudinal direction extend to both end portions of the head substrate 100. The girder 400 is also formed before the signal conductor 201, the common conductor 202, or the common wiring pattern 201a is formed. In this embodiment, as shown in FIGS. 14 and 16, the common electrode pattern 202a is formed. Extends across the beam 400 in the transverse direction of the head substrate 100. In the present embodiment, the protective layer 150 covers a predetermined width region on one side in the short direction of the head substrate 100, and the edge 150 b on the other side in the short direction of the head substrate 100 is more than the edge 140 a of the base layer 140. Also, the head substrate 100 is displaced to the other side in the short side direction of the head substrate 100 and crosses the intermediate portion of the beam portion 400 in the longitudinal direction of the head substrate 100. Therefore, also in the present embodiment, the region on one side in the short direction of the head substrate 100 in the beam portion 400 is covered with the protective layer 150, and the opposite side of the region covered with the protective layer 150 across the boundary 402. The region on the other side in the short direction of the head substrate 100 is not covered with the protective layer 150. Further, of the signal conductor 201, the other side of the head substrate 100 in the short side direction is not covered with the protective layer 150, and the wire bonding pad 212 is exposed. A wire bonding pad 212 and a wiring pattern on the circuit board 300 are connected by a bonding wire 320, and the bonding wire 320 is covered with a protective resin 330 that covers the drive IC 310. Also in this embodiment, the plan view shape of the girder portion is not limited to a rectangle, and may be any shape such as an arc shape. Furthermore, in the present embodiment, the common electrode pattern 202a crosses the upper surface of the beam part 400. However, the common electrode pattern 202a is formed so as to avoid the beam part 400, and the common electrode pattern 202a is formed on the upper surface of the beam part 400. The pattern 202a may not be formed.

  The formation of the protective layer 150 on the head substrate 100 is performed in the same manner as described above with reference to FIGS. 14 and 16, the position of the boundary 402 indicates the position of the edge 100 b of the head substrate 100 that is stacked above the head substrate 100 when the protective layer 150 is formed.

  It will be apparent that the head substrate 100 according to this embodiment can enjoy the same advantages as those described above for the first embodiment.

  FIG. 17 shows a thermal print head 10D according to the fourth embodiment of the present invention. Also in these drawings, the same or similar members or parts as those of the thermal print head 10A according to the first embodiment shown in FIGS. 1 to 4 are given the same reference numerals for detailed description. Omitted.

  The girder portion 400 provided on the head substrate 100 of the thermal print head 10D according to the present embodiment is not formed with the signal conductor 201 on the head substrate 100, for example, in the regions at both ends in the longitudinal direction of the head substrate 100. It is formed by providing a sheet-like sticking object such as a tape 410 having a thickness of 30 to 100 μm. This tape 410 is provided before the protective layer 150 is provided. When the base layer 140 is provided on the head substrate 100, the edge 410 a on one side in the short direction of the head substrate 100 of the tape 410 is the end of the base layer 140. It is set so as to be shifted to one side in the short direction of the head substrate 100 from the edge 140a. Also in this embodiment, the region on one side in the short direction of the head substrate 100 in the beam portion 400 is covered with the protective layer 150, and the opposite side of the region covered with the protective layer 150 with the boundary 402 interposed therebetween. The region on the other side in the short direction of the head substrate 100 is not covered with the protective layer 150. The portion of the signal conductor 201 formed on the base layer 140 is not covered with the protective layer 150, and the wire bonding pad 212 is exposed. Further, the plan view shape of the beam portion 400 is not limited to a rectangle, and may be any shape such as a circle.

  The formation of the protective layer 150 on the head substrate 100 is performed in the same manner as described above with reference to FIGS. In FIG. 14, the position of the boundary 402 indicates the position of the edge 100 b of the head substrate 100 that is stacked above the head substrate 100 when the protective layer 150 is formed. The tape 410 may be left as it is after the step of forming the protective layer 150 or may be removed.

  Note that, when the girder 400 is formed of an adhesive such as the tape 410 as in the present embodiment, it does not matter whether the base layer 140 is formed on the head substrate 100.

  It will be apparent that the head substrate 100 according to this embodiment can enjoy the same advantages as those described above for the first embodiment.

  Of course, the scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope of the matters described in the claims are all included in the scope of the present invention.

  For example, in the embodiment, the shape of the heat generating portion 110 is a common conductor extending in a comb shape from the common electrode pattern 202a on one side of the partial glaze 130 (one side in the short direction of the head substrate 100) on the partial glaze 130. 202 and the resistor layer 220 exposed in a region where the signal conductor 201 extending from the other side of the partial glaze 130 (the other side in the short side of the head substrate 100) is opposed. A thin film type of a type in which a so-called folded-type conductor is formed as described in Japanese Patent Application Laid-Open No. 2012-1111051, and the heat generating portion 110 is formed by facing the common-side conductor and the signal-side conductor on the partial glaze. In the case of forming a protective layer on the head substrate in the thermal print head, the present invention can be similarly applied.

  In the embodiment, the heat generating portion 110 is provided on the partial glaze 130. For example, a so-called full glaze is formed on the head substrate 100, and the heat generating portion 110 is formed at a predetermined portion on the full glaze. In the case of forming the protective layer 150 in the thin film thermal print head, the present invention can be similarly applied. In this case, a girder portion 400 is formed by printing and baking a glass paste having a lower softening temperature than a glass paste for forming a full glaze to a predetermined thickness, or by providing an adhesive such as a tape. The part 400 may be formed.

  Furthermore, in the embodiment, the drive IC is not mounted on the head substrate 100, and the drive IC 310 is mounted on the circuit board 300 disposed adjacent to the head substrate 100 on the heat sink 500. The present invention can be similarly applied to the case where the protective layer 150 is formed on the head substrate 100 in the type of thermal print head in which the driving IC is mounted.

10A Thermal print head 10B Thermal print head 10C Thermal print head 10D Thermal print head 100 Head substrate 100a Main surface (head substrate)
100b Edge (one side in the short direction)
110 Heating part 130 Partial glaze 140 Underlayer 140a Edge (underlayer)
150 Protective layer 150b Edge 201 Signal conductor 201a Termination portion 201b Part formed on base layer (signal conductor)
212 Pad (for wire bonding)
202 Common conductor 202a Common electrode pattern 210 Conductor layer 220 Resistor layer 300 Circuit board 310 Drive IC
320 Bonding wire 330 Protective resin 400 Girder part 400a Edge 410 Tape 500 Heat sink

Claims (33)

Thermal print comprising: a substrate; a plurality of heat generating portions arranged in the longitudinal direction of the substrate on one side of the substrate in the short direction; a conductor connected to each heat generating portion; and a protective layer covering at least the plurality of heat generating portions. In the head
The substrate has a girder having a predetermined thickness, and a predetermined region on one side of the substrate in the short direction of the substrate is covered with the protective layer, and the region covered with the protective layer On the other hand, a region located on the other side in the short direction of the substrate in the girder across the boundary is not covered with the protective layer.   2. The thermal print head according to claim 1, wherein the conductor includes a signal conductor extending from each of the heat generating portions to the other side in the short direction of the substrate.   The thermal print head according to claim 2, wherein the girder is formed in a region avoiding the signal conductor on the other side in the short direction of the substrate than the heat generating portions.   4. The thermal print head according to claim 3, wherein the girder includes those formed at both ends in the longitudinal direction of the substrate.   5. The thermal print head according to claim 1, wherein the girder is formed by printing and baking a predetermined paste material.   The thermal print head according to claim 5, wherein the paste material is a glass-based paste.   The thermal print head according to claim 5 or 6, wherein the signal conductor is formed on an underlayer formed on the substrate, and the beam portion is formed of the same material as the underlayer.   The thermal print head according to claim 7, wherein the girder is formed at the same thickness as the underlayer.   The underlayer is formed in a lower layer on the other side in the short direction of the substrate of the signal conductor, and an edge of the under layer on one side in the short side of the substrate is from the boundary in the girder. The thermal print head according to claim 7, wherein the thermal print head is located on the other side in the short direction of the substrate.   The thermal print head according to claim 9, wherein the girder is independent of the base layer.   The thermal print head according to claim 9, wherein the girder is continuous with the base layer.   The thermal print head according to claim 10, wherein the girder has a rectangular shape in plan view.   The thermal print head according to claim 10, wherein the girder is circular in plan view.   7. The thermal print head according to claim 5, wherein the signal conductor is formed on an underlayer formed on the substrate, and the beam portion is formed so as to overlap the underlayer.   The thermal print head according to any one of claims 1 to 4, wherein the girder portion is formed by an attachment to the substrate.   The thermal print head according to claim 14, wherein the attachment is a tape. Thermal print comprising: a substrate; a plurality of heat generating portions arranged in the longitudinal direction of the substrate on one side of the substrate in the short direction; a conductor connected to each heat generating portion; and a protective layer covering at least the plurality of heat generating portions. A method of manufacturing a head,
The plurality of heat generating portions and the plurality of substrate intermediates after the formation of the conductors are stacked and held in the short direction of the substrate so that the plurality of heat generating portions face each other, and then subjected to sputtering or CVD method. In forming the protective layer,
The substrate intermediate is formed with a girder having a predetermined thickness, and the edge on one side in the short direction of the substrate intermediate is the girder in the lower substrate intermediate on which the substrate intermediate is stacked. A method of manufacturing a thermal print head, comprising: laminating and holding a plurality of the substrate intermediates so as to be positioned in a short-side intermediate portion of the substrate.   The method of manufacturing a thermal print head according to claim 17, wherein the conductor includes a signal conductor extending from each of the heat generating portions to the other side in the short direction of the substrate.   19. The method of manufacturing a thermal print head according to claim 18, wherein the girder is formed in a region avoiding the signal conductor on the other side in the short direction of the substrate than the heat generating portions.   The method for manufacturing a thermal print head according to claim 19, wherein the girder portion includes those formed at both ends in the longitudinal direction of the substrate.   21. The method of manufacturing a thermal print head according to claim 17, wherein the girder is formed by printing and baking a predetermined paste material.   The method for manufacturing a thermal print head according to claim 21, wherein the paste material is a glass-based paste material.   23. The method of manufacturing a thermal print head according to claim 21, wherein the signal conductor is formed on a base layer formed on the substrate, and the beam portion is formed of the same material as the base layer.   The method for manufacturing a thermal print head according to claim 23, wherein the girder is formed with the same thickness as the underlayer.   The underlayer is formed in a lower layer on the other side in the short direction of the substrate of the signal conductor, and an edge of the under layer on the one side in the short direction of the substrate is more than the boundary in the beam portion. The manufacturing method of the thermal print head of Claim 23 or 24 located in the transversal direction other side of the said board | substrate.   26. The method of manufacturing a thermal print head according to claim 25, wherein the girder is independent of the base layer.   26. The method of manufacturing a thermal print head according to claim 25, wherein the girder is continuous with the base layer.   27. The method of manufacturing a thermal print head according to claim 26, wherein the girder has a rectangular shape in plan view.   27. The method of manufacturing a thermal print head according to claim 26, wherein the girder is circular in plan view.   The manufacturing of the thermal print head according to claim 21 or 22, wherein the signal conductor is formed on an underlayer formed on the substrate, and the girders are formed to overlap the underlayer. Method.   The method for manufacturing a thermal print head according to any one of claims 17 to 20, wherein the girder portion is formed by a sticking material to the substrate.   The method for manufacturing a thermal print head according to claim 30, wherein the sticking object is a tape.   The manufacturing method of the thermal print head of Claim 31 or 32 which removes the said sticking thing after formation of the said protective layer.

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