JP7393218B2 - Thermal print head manufacturing method and thermal print head - Google Patents

Description

The present disclosure relates to a method of manufacturing a thermal print head and a thermal print head.

Patent Document 1 discloses an example of a conventional thermal print head. The thermal print head disclosed in this document includes a substrate, an electrode layer, a resistor layer, and a protective layer. The substrate is a plate-shaped member made of an insulating material. The electrode layer is formed on the substrate and forms a current path for selectively passing current through the resistor layer. The electrode layer has a common electrode and a plurality of individual electrodes. The common electrode and the individual electrodes are electrically opposite electrodes. A portion of the resistor layer sandwiched between a part of the common electrode and the individual electrodes in the main scanning direction becomes a heat generating portion. The protective layer is for protecting the electrode layer and is made of glass, for example.

In recent years, with the miniaturization and higher image quality of thermal print heads, the patterns of electrode layers have become finer. Even when such high-definition patterning is required, it is preferable to appropriately configure the conduction path without disconnection or short-circuiting of the electrode layer, and to ensure sufficient conduction between the electrode layer and the resistor layer. .

Japanese Patent Application Publication No. 10-16268

The present disclosure has been devised in view of the above circumstances, and its purpose is to provide a method for manufacturing a thermal print head that can form an electrode layer with appropriately configured conductive paths.

A method for manufacturing a thermal print head provided by a first aspect of the present disclosure includes a substrate preparation step of preparing a substrate, and a resistor layer including a plurality of heat generating parts arranged in a main scanning direction on the substrate. and an electrode layer forming step of forming an electrode layer for energizing the resistor layer. and a plurality of second parts arranged with a second pitch width smaller than the first pitch width, and the substrate is formed by the plurality of first parts when viewed in the thickness direction of the substrate. and a second region where the plurality of second parts are formed when viewed in the thickness direction, and the electrode layer forming step includes forming the plurality of the plurality of second parts in the first region by screen printing. A first patterning step of forming a first part pattern; and a second patterning step of forming the plurality of second part patterns in the second region by a patterning method that allows patterning with higher definition than the screen printing. It is characterized by including a process.

A thermal print head provided by a second aspect of the present disclosure includes a substrate, a plurality of heat generating parts arranged in the main scanning direction, a resistor layer formed on the substrate, and a resistor layer formed on the resistor layer. an electrode layer for supplying electricity, the electrode layer includes a plurality of first parts, a plurality of second parts, and a plurality of bonding parts, and each of the plurality of first parts has a secondary part. Each of the plurality of second parts has a strip shape extending in the scanning direction and is arranged in the main scanning direction with a first pitch width, and each of the plurality of second parts has a strip shape extending in the sub scanning direction and has a first pitch width. The plurality of bonding parts are arranged in the main scanning direction with a second pitch width smaller than , the plurality of first parts are patterned by screen printing, and the plurality of second parts are patterned by a method that allows patterning with higher definition than the screen printing. .

According to the method for manufacturing a thermal print head of the present disclosure, it is possible to form an electrode layer in which conductive paths are appropriately configured.

FIG. 1 is a plan view showing a thermal print head according to a first embodiment. 2 is a sectional view taken along line II-II in FIG. 1. FIG. FIG. 2 is an enlarged plan view of a main part of FIG. 1; FIG. FIG. 4 is an enlarged cross-sectional view of a main part taken along line IV-IV in FIG. 3; FIG. 3 is a cross-sectional view showing one step in the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a plan view showing one step of the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a cross-sectional view showing one step in the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a plan view showing one step of the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a cross-sectional view showing one step in the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a cross-sectional view showing one step in the method for manufacturing the thermal print head according to the first embodiment. FIG. 3 is a sectional view showing a thermal print head according to a modification of the first embodiment. FIG. 7 is a plan view showing a thermal print head according to a second embodiment. 13 is a sectional view taken along line XIII-XIII in FIG. 12. FIG. FIG. 7 is a plan view showing one step in a method for manufacturing a thermal print head according to a second embodiment. FIG. 7 is a cross-sectional view showing a thermal print head according to a modification of the second embodiment. FIG. 7 is a cross-sectional view showing a thermal print head according to a modification of the second embodiment. FIG. 7 is a plan view showing a thermal print head according to a third embodiment. 18 is a sectional view taken along the line XVIII-XVIII in FIG. 17. FIG. FIG. 7 is a plan view showing one step in a method for manufacturing a thermal print head according to a third embodiment. 20 is a sectional view taken along line XX-XX in FIG. 19. FIG. FIG. 7 is a cross-sectional view showing one step in a method for manufacturing a thermal print head according to a third embodiment. FIG. 7 is a plan view showing one step in a method for manufacturing a thermal print head according to a third embodiment. 23 is a sectional view taken along line XXIII-XXIII in FIG. 22. FIG. FIG. 7 is a plan view showing one step in a method for manufacturing a thermal print head according to a third embodiment. 25 is a sectional view taken along line XXV-XXV in FIG. 24. FIG. FIG. 7 is an enlarged sectional view of a main part of a thermal print head according to a modification.

A method for manufacturing a thermal print head and a preferred embodiment of the thermal print head according to the present disclosure will be described below with reference to the drawings. Terms such as "first", "second", "third", etc. in this disclosure are used merely as labels and are not necessarily intended to attach a permutation to those objects.

In this disclosure, "a thing A is formed on a thing B" and "a thing A is formed on a thing B" mean "a thing A is formed on a thing B" unless otherwise specified. "It is formed directly on object B," and "It is formed on object B, with another object interposed between object A and object B." Similarly, "something A is placed on something B" and "something A is placed on something B" mean "something A is placed on something B" unless otherwise specified. This includes ``directly placed on object B'' and ``placed on object B with another object interposed between object A and object B.'' Similarly, "a certain object A is located on a certain object B" means, unless otherwise specified, "a certain object A is in contact with a certain object B, and a certain object A is located on a certain object B." ``The fact that a certain thing A is located on a certain thing B while another thing is interposed between the certain thing A and the certain thing B.'' In addition, "a certain object A overlaps a certain object B when viewed in a certain direction" means, unless otherwise specified, "a certain object A overlaps all of a certain object B" and "a certain object A overlaps with a certain object B". This includes "overlapping a part of something B."

<First embodiment>
1 to 4 show a thermal print head A1 according to a first embodiment. The thermal print head A1 includes a substrate 1, an electrode layer 3, a resistor layer 4, a protective layer 5, a plurality of drive ICs 71, a sealing resin 72, a plurality of connectors 73, a wiring board 74, and a heat dissipation member 75. Thermal print head A1 is incorporated into a printer that prints on print medium 82. The print medium 82 is sandwiched between the thermal print head A1 and the platen roller 81 as shown in FIG. 2, and is conveyed in the sub-scanning direction by the rotational movement of the platen roller 81. Examples of the print medium 82 include thermal paper for creating barcode sheets and receipts.

FIG. 1 is a plan view showing the thermal print head A1. FIG. 2 is a sectional view taken along line II-II in FIG. FIG. 3 is an enlarged plan view of a main part of FIG. 1. FIG. 4 is an enlarged sectional view of a main part taken along line IV-IV in FIG. 3. In FIG. 1, the protective layer 5 and the wire 61 are omitted, and the sealing resin 72 is shown with an imaginary line (two-dot chain line). In FIG. 3, the protective layer 5 is omitted. For convenience of understanding, in FIGS. 1 to 4, the main scanning direction is the x direction, the sub-scanning direction is the y direction, and the thickness direction of the substrate 1 is the z direction. During printing, the print medium is sent in the sub-scanning direction y in the direction indicated by the arrow in the figure. In the sub-scanning direction y, the direction indicated by the arrow in the figure is defined as downstream, and the opposite direction is defined as upstream. Further, in the thickness direction z, the direction indicated by the arrow in the figure is defined as the upper direction, and the opposite direction is defined as the lower direction.

In the thermal print head A1, the substrate 1 and the wiring board 74 are adjacent to each other in the sub-scanning direction y, as shown in FIG. 2, and each is mounted on a heat radiating member 75. The wiring board 74 is a board in which a base material layer made of, for example, glass epoxy resin and a wiring layer made of Cu (copper) or the like are laminated. The heat radiation member 75 is made of metal such as Al (aluminum). The drive IC 71 on the substrate 1 and the wiring on the wiring board 74 are connected by wires 61, as shown in FIG. A connector 73 is provided on the wiring board 74. The thermal print head A1 has a plurality of heat generating parts 41 arranged in the main scanning direction x, which will be explained in detail later. The heat generating section 41 is selectively driven to generate heat by the drive IC 71 in accordance with a print signal transmitted from the outside via the connector 73. As shown in FIG. 2, in the thermal print head A1, a print medium 82 is pressed against a heat generating part 41 by a platen roller 81, and printing is performed on the print medium 82 by the heat generated by the heat generating part 41. The thermal print head A1 may not include the wiring board 74, and the connector 73 may be mounted on the board 1.

As shown in FIG. 1, the substrate 1 has a plate shape that extends long in the main scanning direction x. The substrate 1 supports the electrode layer 3, the resistor layer 4, the protective layer 5, and the drive IC 71. The substrate 1 includes a first region 10A and a second region 10B when viewed in the thickness direction z. The second region 10B is a region where the electrode layer 3 is formed with relatively higher definition than the first region 10A. The electrode layer 3 formed in the first region 10A is patterned, for example, by screen printing, and the electrode layer 3 formed in the second region 10B is patterned using a patterning method (this embodiment) that allows patterning with higher definition than screen printing. Formally, it is formed by dispenser application). The substrate 1 includes a base material 11 and a glaze layer 12.

The base material 11 is made of ceramic such as AlN (aluminum nitride), Al ₂ O ₃ (alumina), and zirconia. The base material 11 has a thickness of, for example, 0.6 mm or more and 1.0 mm or less. The base material 11 has a rectangular shape that extends long in the main scanning direction x when viewed in the thickness direction z. The base material 11 has a main surface 11a. The main surface 11a is the upper surface of the base material 11. The main surface 11a faces upward in the thickness direction z.

Glaze layer 12 is formed on base material 11 . Glaze layer 12 covers main surface 11a. Glaze layer 12 is made of a glass material such as amorphous glass. Glaze layer 12 includes a partial glaze 121 and a glass layer 122. Note that the glaze layer 12 may not include the glass layer 122 and may be composed only of the partial glaze 121. Alternatively, the substrate 1 may not include the glaze layer 12.

The partial glaze 121 extends long in the main scanning direction x. The partial glaze 121 bulges in the thickness direction z when viewed in the main scanning direction x. As shown in FIG. 4, the partial glaze 121 has an arc-shaped cross section (yz cross section) taken along a plane perpendicular to the main scanning direction x. The partial glaze 121 is provided in order to make it easier to press a heat-generating portion of the resistor layer 4 (a heat-generating portion 41 to be described later) against the print medium 82 . Further, the partial glaze 121 is provided as a heat storage layer that accumulates heat from the heat generating portion 41. The partial glaze 121 has a dimension (maximum dimension) in the thickness direction z that is larger than the glass layer 122 .

The glass layer 122 is formed adjacent to the partial glaze 121 and has a flat top surface. The glass layer 122 partially overlaps the partial glaze 121 . The thickness of the glass layer 122 is, for example, about 2.0 μm.

In the glaze layer 12, the partial glaze 121 is made of a glass material with a softening point of, for example, 800°C or more and 850°C or less, and the glass layer 122 is made of a glass material with a softening point of, for example, about 680°C. That is, the glass material forming the glass layer 122 has a lower softening point than the glass material forming the partial glaze 121. Note that the glass material forming the partial glaze 121 and the glass material forming the glass layer 122 may have the same softening point.

The electrode layer 3 is for configuring a path for supplying electricity to the resistor layer 4, and is made of a conductive material. The electrode layer 3 is made of resinate Au (gold) to which, for example, rhodium, vanadium, bismuth, silicon, or the like is added as an additive element. The electrode layer 3 may have a structure in which a plurality of Au layers are laminated. Moreover, the electrode layer 3 may have a structure in which a Cu layer and a Ti layer are laminated, or may be formed only in a Cu layer. The thickness of the electrode layer 3 is, for example, 0.6 μm or more and 1.2 μm or less. Electrode layer 3 is formed on glaze layer 12. As shown in FIGS. 3 and 4, the electrode layer 3 includes a common electrode 33 and a plurality of individual electrodes 36.

The common electrode 33 has a plurality of common electrode strip parts 34 and connecting parts 35, as shown in FIG. The connecting portion 35 is disposed near the downstream edge of the substrate 1 in the sub-scanning direction y, and has a band shape extending in the main-scanning direction x. In order to reduce the resistance value of the connecting portion 35, an Ag layer may be laminated on the connecting portion 35. The plurality of common electrode strips 34 each extend from the connecting portion 35 in the sub-scanning direction y, and are arranged in the main-scanning direction x. Each of the plurality of common electrode strips 34 includes a base portion 341 and an extension portion 342. The plurality of base parts 341 are arranged in the main scanning direction x with a pitch width Pt1 (see FIG. 3). This pitch width Pt1 is, for example, 10 μm or more and 100 μm or less (100 μm in one example). The width of each base 341 (dimension in the main scanning direction In one example, it is 40 μm). The extending portion 342 extends from the base portion 341 toward the resistor layer 4 . The extending portion 342 has a strip shape that is long in the sub-scanning direction y in the thickness direction z. In the example shown in FIG. 3, the width of the extending portion 342 (dimension in the main scanning direction x) is smaller than the width of the base portion 341 (dimension in the main scanning direction x). This suppresses the occurrence of disconnection in the common electrode strip 34 during the formation of the common electrode strip 34 (during the preliminary firing step after the preliminary coating step described later). Note that the width of the base portion 341 and the width of the extension portion 342 may be substantially the same. The plurality of extension parts 342, like the plurality of base parts 341, are arranged in the main scanning direction x with a pitch width Pt1 (see FIG. 3). The width (dimension in the main scanning direction x) of each of the plurality of extension parts 342 is, for example, 10 μm or more and 100 μm or less (60 μm in one example), and the distance between two adjacent extension parts 342 in the main scanning direction x is For example, it is 10 μm or more and 100 μm or less (40 μm in one example).

The plurality of individual electrodes 36 are for partially conducting to the resistor layer 4 and have opposite polarity to the common electrode 33. Each individual electrode 36 extends from the resistor layer 4 toward each drive IC 71. The plurality of individual electrodes 36 are arranged in the main scanning direction x, as shown in FIG. Each individual electrode 36 includes an individual electrode strip portion 38, a connecting portion 37, and a bonding portion 39.

As shown in FIG. 3, each of the plurality of individual electrode strips 38 extends from each connecting portion 37 in the sub-scanning direction y. The plurality of individual electrode strips 38 are arranged in the main scanning direction x with a pitch width Pt2 (see FIG. 3). Each of the plurality of individual electrode strips 38 includes a base 381 and an extension 382. Each of the plurality of base portions 381 has a long strip shape in the sub-scanning direction y when viewed in the thickness direction z. Each base portion 381 is connected to each connecting portion 37 . The plurality of base parts 381 are arranged in the main scanning direction x with a pitch width Pt2 (see FIG. 3). This pitch width Pt2 is the same as the pitch width Pt1, and is, for example, 10 μm or more and 100 μm or less (100 μm in one example). The width of each base 381 (dimension in the main scanning direction In one example, it is 40 μm). The extending portion 382 extends from the base portion 381 toward the resistor layer 4 . The extending portion 382 has a strip shape that is long in the sub-scanning direction y in the thickness direction z. The extending portion 382 is located between two adjacent common electrode strip portions 34 (common electrode 33). The width of the extending portion 382 (dimension in the main scanning direction x) is smaller than the width of the base portion 381 (dimension in the main scanning direction x). In the example shown in FIG. 3, this suppresses the occurrence of disconnection in the individual electrode strip portions 38 during formation of the individual electrode strip portions 38 (during the advance firing step after the advance coating step described later). Note that the width of the base portion 381 and the width of the extension portion 382 may be substantially the same. The plurality of extending portions 382, like the plurality of base portions 381, are arranged in the main scanning direction x with a pitch width Pt2 (see FIG. 3). The width (dimension in the main scanning direction x) of each of the plurality of extension parts 382 is, for example, 10 μm or more and 100 μm or less (60 μm in one example), and the distance between two adjacent extension parts 382 in the main scanning direction x is For example, it is 10 μm or more and 100 μm or less (40 μm in one example).

Each of the plurality of connecting parts 37 is a part extending from each individual electrode strip part 38 toward each bonding part 39, as shown in FIG. Each of the plurality of connecting parts 37 includes a parallel part 371 and an oblique part 372. Each of the plurality of parallel parts 371 has one end connected to the bonding part 39 and extends along the sub-scanning direction y. The plurality of parallel parts 371 are arranged in the main scanning direction x with a pitch width Pt3 (see FIG. 3). This pitch width Pt3 is, for example, 10 μm or more and 100 μm or less (40 μm in one example). The width of each parallel portion 371 (dimension in the main scanning direction or less (30 μm in one example). Each of the plurality of oblique portions 372 is inclined with respect to the sub-scanning direction y. Similar to the plurality of parallel parts 371, the plurality of diagonal parts 372 are arranged with a pitch width Pt3. Each of the plurality of oblique portions 372 is sandwiched between each parallel portion 371 and each individual electrode strip portion 38 in the sub-scanning direction y. Further, the plurality of individual electrodes 36 are integrated into one of the plurality of drive ICs 71. Therefore, the boundary between the parallel portion 371 and the diagonal portion 372 at one end in the main scanning direction x in FIG. 3 and the boundary between the parallel portion 371 and the diagonal portion 372 at the other end in the sub-scanning direction y are A deviation L has occurred.

Each connecting portion 37 includes a first edge portion 37a, a second edge portion 37b, and an intermediate portion 37c, as shown in FIGS. 3 and 4. The first edge portion 37a is an end portion on the downstream side in the sub-scanning direction y, and is a portion connected to each individual electrode strip portion 38. The first edge portion 37a is formed on each individual electrode strip 38, and overlaps each individual electrode strip 38 when viewed in the thickness direction z. The second edge portion 37b is an end portion on the upstream side in the sub-scanning direction y, and is a portion connected to each bonding portion 39. The second edge portion 37b is formed on each bonding portion 39, and overlaps each bonding portion 39 when viewed in the thickness direction z. The intermediate portion 37c connects the first edge portion 37a and the second edge portion 37b. The intermediate portion 37c does not overlap the first edge portion 37a and the second edge portion 37b when viewed in the sub-scanning direction y, but overlaps each individual electrode strip portion 38 or each bonding portion 39.

As shown in FIG. 3, the bonding portion 39 is formed at the upstream end of the individual electrode 36 in the sub-scanning direction y, and is connected to the connecting portion 37 (parallel portion 371). A wire 61 for connecting each individual electrode 36 and each drive IC 71 is bonded to each bonding portion 39 . The plurality of bonding sections 39 include a plurality of first bonding sections 39A and a plurality of second bonding sections 39B. The second bonding portion 39B is located further away from the resistor layer 4 than the first bonding portion 39A in the sub-scanning direction y. The second bonding portion 39B is connected to a parallel portion 371 sandwiched between two adjacent first bonding portions 39A. With such a configuration, the plurality of bonding parts 39 are prevented from interfering with each other even though the width is wider than most parts of the connecting part 37.

Of the electrode layer 3, a plurality of common electrode strip portions 34 (common electrode 33), a connecting portion 35 (common electrode 33), a plurality of individual electrode strip portions 38 (a plurality of individual electrodes 36), and a plurality of bonding portions 39 (The plurality of individual electrodes 36) are formed in the first region 10A of the substrate 1. Further, among the electrode layer 3, the plurality of connecting portions 37 (the plurality of individual electrodes 36) are formed in the second region 10B of the substrate 1. In this embodiment, the plurality of common electrode strip portions 34 and the plurality of individual electrode strip portions 38 each correspond to “a plurality of first portions” as described in the claims. Further, the plurality of connecting portions 37 correspond to "the plurality of second parts" described in the claims. Since the plurality of first parts (the plurality of common electrode strip parts 34, the plurality of individual electrode strip parts 38, and the plurality of bonding parts 39) and the plurality of second parts (the plurality of connection parts 37) are formed in different ways, Edges of the plurality of first parts (for example, edges of each individual electrode strip 38 extending in the sub-scanning direction y) and edges of the plurality of second parts (for example, edges of each connecting part 37 extending in the sub-scanning direction y) ) has different linearity. Note that the shape and arrangement of each part of the electrode layer 3 are not particularly limited, and can have various configurations. Moreover, the material of each part of the electrode layer 3 is not limited either.

The resistor layer 4 has a higher resistivity than the material constituting the electrode layer 3. The resistor layer 4 is made of, for example, ruthenium oxide. The resistor layer 4 is formed on the partial glaze 121, as shown in FIG. As shown in FIGS. 1 and 3, the resistor layer 4 has a strip shape extending in the main scanning direction x when viewed in the thickness direction z. The resistor layer 4 crosses each extension 342 of the plurality of common electrode strips 34 (common electrode 33) and each extension 382 of the plurality of individual electrode strips 38 (multiple individual electrodes 36). There is. The resistor layer 4 is laminated on the side opposite to the substrate 1 with respect to the plurality of common electrode strips 34 and the plurality of individual electrode strips 38. A portion of the resistor layer 4 sandwiched between each common electrode strip portion 34 and each individual electrode strip portion 38 serves as a heat generating portion 41 . The plurality of heat generating parts 41 generate heat by being partially energized by the electrode layer 3 . Print dots are formed by the heat generated by each heat generating section 41. The plurality of heat generating parts 41 are arranged in the main scanning direction x. When the dimensions of the substrate 1 in the main scanning direction x are the same, the greater the number of heat generating parts 41 arranged in the main scanning direction x, the greater the dot density of the thermal print head A1. The thickness of the resistor layer 4 is, for example, 3 μm or more and 6 μm or less. The material and thickness of the resistor layer 4 are not limited. In the example shown in FIG. 4, the resistor layer 4 is formed on the top of the partial glaze 121, but it does not need to be formed on the top of the partial glaze 121. Bye.

The protective layer 5 is for protecting the electrode layer 3, the resistor layer 4, and the like. However, the protective layer 5 exposes a region including the plurality of bonding parts 39 of the plurality of individual electrodes 36. The protective layer 5 is made of, for example, amorphous glass. The protective layer 5 may include a first layer made of amorphous glass and a second layer made of SiAlON, for example. SiAlON is a silicon nitride-based engineering ceramic made by synthesizing silicon nitride (Si ₃ N ₄ ), alumina (Al ₂ O ₃ ), and silica (SiO ₂ ). The second layer is formed by sputtering, for example. The second layer may be made of SiC (silicon carbide) instead of SiAlON.

The protective layer 5 includes a first covering part 51 and a second covering part 52, as shown in FIG. The first covering portion 51 is a portion of the protective layer 5 that overlaps the partial glaze 121 when viewed in the thickness direction z. The first covering portion 51 is formed on the partial glaze 121. The first covering portion 51 includes a raised portion 511 . The raised portion 511 overlaps the resistor layer 4 (each heat generating portion 41) when viewed in the thickness direction z. Since the resistor layer 4 is arranged so as to be raised relative to each surface of the electrode layer 3 or the partial glaze 121, the raised portion 511 has a raised shape along the resistor layer 4. The second covering portion 52 is a portion of the protective layer 5 that does not overlap the partial glaze 121 when viewed in the thickness direction z. The second covering part 52 is arranged at both ends of the first covering part 51 in the sub-scanning direction y when viewed in the thickness direction z. The second covering section 52 on the upstream side in the sub-scanning direction y is formed in a region extending from the downstream end edge of the first covering section 51 in the sub-scanning direction y to the front side of the plurality of bonding sections 39 .

The drive IC 71 selectively energizes the plurality of individual electrodes 36 to partially generate heat in the resistor layer 4 . The drive IC 71 is provided with a plurality of pads. The pads of the drive IC 71 and the plurality of individual electrodes 36 are connected via a plurality of wires 61 bonded to each pad. The wire 61 is made of Au. As shown in FIGS. 1 and 2, the drive IC 71 and the wires 61 are covered with a sealing resin 72. The sealing resin 72 is insulating and made of, for example, a black soft resin. Further, the drive IC 71 and the connector 73 are connected by a signal line (not shown).

Next, an example of a method for manufacturing the thermal print head A1 will be described with reference to FIGS. 5 to 10. 5 to 10, FIGS. 6 and 8 are principal part plan views showing one step of the method for manufacturing the thermal print head A1, and correspond to FIG. 3. The other figures are main part sectional views showing one step of the method for manufacturing the thermal print head A1, and correspond to FIG. 4.

First, a substrate 1 shown in FIG. 5 is prepared. The step of preparing the substrate 1 (substrate preparation step) includes a base material preparation step and a glaze layer forming step. In the base material preparation step, a base material 11 made of ceramic, for example, is prepared. The ceramic material may be, for example, AlN, Al ₂ O ₃ or zirconia. The base material 11 has a main surface 11a facing upward in the thickness direction z. In the glaze layer forming step, a glaze layer 12 is formed on the main surface 11a of the base material 11. The step of forming glaze layer 12 includes a partial glaze forming step of forming partial glaze 121 and a glass layer forming step of forming glass layer 122. In the partial glaze forming step, the glass paste constituting the partial glaze 121 is screen printed, for example, and fired at a firing temperature of, for example, 800° C. or higher and 850° C. or lower. As a result, a partial glaze 121 is formed. In the glass layer forming step, the glass paste constituting the glass layer 122 is screen printed, for example, and fired at a firing temperature of, for example, about 680°C. This forms the glass layer 122. The firing temperatures in the partial glaze forming step and the glass layer forming step are appropriately changed based on the softening points of the glass paste forming the partial glaze 121 and the glass paste forming the glass layer 122.

Next, an electrode layer 3 is formed on the substrate 1. The process of forming the electrode layer 3 (electrode layer forming process) includes a preceding coating process, a preceding baking process, a subsequent coating process, and a subsequent baking process.

In the electrode layer forming step, first, a preliminary coating step is performed. In the preliminary coating step, as shown in FIG. 6, a conductive paste 30A is coated on the first region 10A of the substrate 1. The conductive paste 30A is, for example, resinate Au paste. The preliminary coating step is performed, for example, by screen printing. The conductive paste 30A is applied to a plurality of common electrode strip portions 34 and a connecting portion 35 (common electrode 33), a plurality of individual electrode strip portions 38, and a plurality of bonding portions 39 (a plurality of It is formed in substantially the same shape as each pattern shape of the individual electrodes 36). In other words, the plurality of common electrode strips 34 and the connecting portions 35 of the common electrode 33 and the plurality of individual electrode strips 38 and the plurality of bonding portions 39 of the plurality of individual electrodes 36 are patterned by the preliminary coating step. The preceding coating process corresponds to the "first patterning process" described in the claims.

Next, a preliminary firing step is performed. In the preliminary firing step, the conductive paste 30A applied in the preliminary coating step is fired. As a result, as shown in FIG. Individual electrodes 36) are formed. Note that a step of drying the conductive paste 30A may be further added between the preceding coating step and the preceding baking step.

Next, a subsequent coating step is performed. In the subsequent coating step, as shown in FIG. 8, a conductive paste 30B is coated on the second region 10B of the substrate 1. The conductive paste 30B is made of the same material as the conductive paste 30A, and is, for example, resinate Au paste. The subsequent application step is performed using a dispenser, for example. The conductive paste 30B is formed in the subsequent coating process to have substantially the same pattern shape as the plurality of connecting portions 37 (the plurality of individual electrodes 36) in the electrode layer 3. That is, patterning of the plurality of connecting portions 37 is performed in the subsequent coating step. The second coating process corresponds to the "second patterning process" described in the claims.

Next, a subsequent coating step is performed. In the subsequent firing process, the conductive paste 30B applied in the subsequent coating process is fired. Thereby, as shown in FIG. 9, a plurality of connecting portions 37 are formed. Note that a step of drying the conductive paste 30B may be further added between the subsequent coating step and the subsequent baking step.

Next, as shown in FIG. 10, a resistor layer 4 is formed. In the step of forming the resistor layer 4 (resistor layer forming step), a resistor paste is screen printed on the partial glaze 121. The resistor paste includes a resistor such as ruthenium oxide. The resistor paste is formed in a strip shape extending in the main scanning direction x on the partial glaze 121, and intersects each common electrode strip portion 34 (extension portion 342) and each individual electrode strip portion 38 (extension portion 382). do. Then, the screen-printed resistor paste is fired. As a result, the resistor layer 4 shown in FIG. 10 is formed.

Next, a protective layer 5 is formed. In the step of forming the protective layer 5 (protective layer forming step), the glaze layer 12, the electrode layer 3 (excluding the plurality of bonding parts 39) and the resistor are exposed to the outside above the thickness direction z of the base material 11. On top of layer 4, a glass paste constituting protective layer 5 is screen printed. Then, the screen-printed glass paste is fired. As a result, the protective layer 5 is formed.

Thereafter, the thermal print head A1 shown in FIGS. 1 to 4 is manufactured by performing assembly steps such as mounting the drive IC 71, bonding the wires 61, and attaching the substrate 1 and the wiring board 74 to the heat dissipation member 75.

The functions and effects of the method for manufacturing the thermal print head A1 are as follows.

The method for manufacturing the thermal print head A1 includes an electrode layer forming process including a first patterning process (preliminary coating process) and a second patterning process (subsequent coating process). In the first patterning step, a plurality of first part patterns are formed by screen printing. In this embodiment, as the plurality of first parts, for example, patterns of a plurality of common electrode strip parts 34, a plurality of individual electrode strip parts 38, and a plurality of bonding parts 39 are formed. In the second patterning step, a plurality of second part patterns are formed using a method that allows patterning with higher definition than screen printing. In this embodiment, for example, patterns of a plurality of connecting portions 37 are formed as the plurality of second portions. The plurality of first parts are arranged with a first pitch width (pitch widths Pt1, Pt2), and even by patterning by screen printing, it is possible to form an appropriate pattern without short circuits or disconnections. On the other hand, the plurality of second parts are arranged with a second pitch width (pitch width Pt3) smaller than the first pitch width, and patterning by screen printing may cause short circuits, disconnections, etc. Therefore, the plurality of second parts are patterned using a method that allows patterning with higher definition than screen printing. Thereby, the plurality of second parts can be formed into appropriate patterns without short circuits or disconnections. Therefore, according to the method for manufacturing the thermal print head A1, it is possible to form the electrode layer 3 in which the conductive path is appropriately configured.

In the method for manufacturing the thermal print head A1, a plurality of second portions are patterned in a subsequent coating process. In the subsequent application step, the conductive paste 30B is applied to the second region 10B by dispenser application. According to this configuration, a plurality of second portions can be patterned with higher definition than screen printing. Therefore, the plurality of second parts having a finer pattern shape than the plurality of first parts can be appropriately formed without causing short circuits or disconnections. Note that as a method for patterning the plurality of second parts, for example, a method may be considered in which the conductive paste 30B is applied by screen printing and then patterned by etching. However, this patterning method requires mask formation by lithography, etching, and mask removal, and there is a concern that manufacturing costs will increase. Therefore, in the method for manufacturing the thermal print head A1, an increase in manufacturing costs is suppressed.

In the method for manufacturing the thermal print head A1, in the first patterning step (preliminary coating step), a plurality of first portions are patterned by screen printing. Patterning by screen printing has lower definition than patterning by dispenser coating, but the cycle time for coating (printing) is short, so it has high manufacturing efficiency. Therefore, compared to the case where all of the plurality of first parts and the plurality of second parts are patterned by dispenser coating, the method for manufacturing the thermal print head A1 suppresses a decrease in manufacturing efficiency while ensuring that the conductive paths are properly formed. A structured electrode layer 3 can be formed.

In the manufacturing method according to the first embodiment, the electrode layer forming step is not limited to the method described above. For example, after the preceding coating process, the subsequent coating process is performed, and then the preceding firing process and the subsequent firing process are performed at once. Thereby, the electrode layer 3 may be formed. In this case, it is necessary to transport the substrate 1 from the screen printing machine to the dispenser between the preceding coating step and the subsequent coating step. There is a possibility that the conductive paste 30A may flow out to an unintended location due to the vibrations generated during this transportation. Therefore, for example, if the conductive paste 30A is dried after the preceding coating step and before the subsequent coating step and then transported, the above-mentioned outflow can be suppressed. For example, after forming a plurality of second parts (a plurality of connecting parts 37) by changing the order of the preceding coating process and the following coating process, the plurality of first parts (a plurality of individual electrode strip parts 38, etc.) are formed. ) may be formed. That is, after applying the conductive paste 30B to the second region 10B by dispenser application, the conductive paste 30B is fired. Then, after applying the conductive paste 30A to the first region 10A by screen printing, the conductive paste 30A is fired. Thereby, the electrode layer 3 may be formed. In this case, for example, a thermal print head A2 shown in FIG. 11 is formed. In the thermal print head A2 shown in FIG. 11, the first edge portion 37a of each connecting portion 37 is not formed on each individual electrode strip 38, but is formed between each individual electrode strip 38 and the substrate 1. The arrangement is interposed between the two. Further, the second edge portion 37b of each connecting portion 37 is not formed on each bonding portion 39, but is interposed between each bonding portion 39 and the glass layer 122 (substrate 1). .

<Second embodiment>
12 and 13 show a thermal print head B1 according to a second embodiment. FIG. 12 is a plan view showing the thermal print head B1, and corresponds to the enlarged plan view of the main part in FIG. 3. 13 is a sectional view taken along the line XIII-XIII in FIG. 12, and corresponds to the enlarged sectional view of the main part in FIG. 4.

As shown in FIGS. 12 and 13, the thermal print head B1 differs from the thermal print head A1 in the structure of the electrode layer 3.

As shown in FIG. 12, in the electrode layer 3 of the thermal print head B1, the width of each connecting portion 37 (each individual electrode 36) is larger than the width of each connecting portion 37 in the thermal print head A1. In this embodiment, in the plurality of connecting parts 37, the plurality of parallel parts 371 and the plurality of oblique parts 372 are each arranged with a pitch width Pt3 (see FIG. 12) similarly to the thermal print head A1. However, the width of each parallel portion 371 (dimension in the main scanning direction The thickness is greater than or equal to 100 μm (10 μm in one example). Similarly, the width of each diagonal portion 372 is, for example, 10 μm or more and 100 μm or less (30 μm in one example), and the distance between two adjacent diagonal portions 372 is, for example, 10 μm or more and 100 μm or less (10 μm in one example). be.

As shown in FIG. 12, among the plurality of parallel parts 371, the parallel part 371 connected to the second bonding part 39B includes a thin wire part 371B. Each thin wire portion 371B is located on the upstream side in the sub-scanning direction y among the parallel portions 371 connected to each second bonding portion 39B, and is sandwiched between two adjacent first bonding portions 39A. The thin line portion 371B has a width (length in the main scanning direction x) smaller than other portions in each parallel portion 371.

As shown in FIG. 13, in each individual electrode 36, a connecting portion 37 is formed integrally with an individual electrode strip portion 38 and a bonding portion 39. As shown in FIG. The first edge portion 37a of each connecting portion 37 does not overlap each individual electrode strip portion 38 when viewed in the thickness direction z, and the second edge portion 37b of each connecting portion 37 does not overlap with each individual electrode strip portion 38 when viewed in the thickness direction z. , do not overlap each bonding portion 39. In each connecting portion 37, the first edge portion 37a, the second edge portion 37b, and the intermediate portion 37c are in contact with the glass layer 122 (glaze layer 12), respectively.

In this embodiment, the plurality of common electrode strips 34 (common electrodes 33) and the plurality of individual electrode strips 38 (the plurality of individual electrodes 36) of the electrode layer 3 are located in the first region 10A of the substrate 1. It is formed. Further, in the electrode layer 3, the plurality of connecting portions 37 (the plurality of individual electrodes 36) and the plurality of bonding portions 39 (the plurality of individual electrodes 36) are formed in the second region 10B of the substrate 1. In this embodiment, the plurality of common electrode strip portions 34 and the plurality of individual electrode strip portions 38 each correspond to “a plurality of first portions” as described in the claims. Further, the plurality of connecting portions 37 correspond to "the plurality of second parts" described in the claims.

Next, an example of a method for manufacturing the thermal print head B1 will be described with reference to FIG. 14. FIG. 14 is a plan view showing one step of the method for manufacturing the thermal print head B1, and corresponds to FIG. 12.

The method for manufacturing the thermal print head B1 differs from the method for manufacturing the thermal print head A1 in the electrode layer forming process. The electrode layer forming process in this embodiment includes a coating process, a baking process, and a partial removal process.

In the electrode layer forming step in this embodiment, a coating step is first performed. In the coating process, the conductive paste 30C is applied to the substrate 1 prepared in the substrate preparation process. The conductive paste 30C is made of the same material as the conductive pastes 30A and 30B, and is, for example, resinate Au paste. The coating process is performed by screen printing. In the coating process, as shown in FIG. 14, a conductive paste having approximately the same shape as the pattern shape of the plurality of common electrode strips 34 and connecting portions 35, and the plurality of individual electrode strips 38 is applied to the first region 10A. 30C is formed, and a solid pattern is formed on the entire surface of the second region 10B. The coating process of this embodiment includes a first coating process of coating the conductive paste 30C on the first area 10A, and a second coating process of coating the conductive paste 30C on the second area 10B. The process and the second coating process are performed at once. The conductive paste 30C formed in the first region 10A by the first coating process is formed in substantially the same pattern shape as the plurality of common electrode strips 34 and connecting portions 35, and the plurality of individual electrode strips 38. Therefore, in the first coating step, the plurality of common electrode strips 34 and the connecting portions 35, and the plurality of individual electrode strips 38 (the plurality of first portions) are patterned.

Next, a firing process is performed. In the baking process, the conductive paste 30C applied in the coating process is baked. As a result, a fired body of the conductive paste 30C is formed. The firing process of this embodiment includes a first firing process of firing the conductive paste 30C applied to the first area 10A, and a second firing process of firing the conductive paste 30C (solid pattern) applied to the second area 10B. The first firing step and the second firing step are performed at once. Note that a step of drying the conductive paste 30C may be further added between the coating step and the baking step.

Next, a partial removal step is performed. In the partial removal step, the solid pattern formed in the second region 10B is partially removed by laser processing. As a result, a plurality of connecting portions 37 and a plurality of bonding portions 39 are formed. Therefore, the pattern shapes of the plurality of connecting parts 37 and the plurality of bonding parts 39 (the plurality of second parts) are formed by the partial removal process.

In this embodiment, the first application step of applying the conductive paste 30C to the first region 10A corresponds to the "first patterning step" described in the claims. Further, the second application step of applying the conductive paste 30C to the second region 10B corresponds to the "coating step" described in the claims, and the second application step of applying the conductive paste 30C to the second region 10B. The combination of the step, the second firing step for firing the same, and the partial removal step corresponds to the "second patterning step" described in the claims.

After that, the thermal print head B1 is manufactured by performing a resistor layer forming process, a protective layer forming process, and an assembly process in the same manner as in the manufacturing method according to the first embodiment.

The functions and effects of the method for manufacturing the thermal print head B1 are as follows.

The method for manufacturing the thermal print head B1 includes an electrode layer forming step including a first patterning step and a second patterning step, similar to the method for manufacturing the thermal print head A1. In the first patterning step, a plurality of first part patterns are formed by screen printing. In this embodiment, for example, a plurality of common electrode strip portions 34 and a plurality of individual electrode strip portions 38 are formed as the plurality of first portions. In the second patterning step, a plurality of second part patterns are formed using a method that allows patterning with higher definition than screen printing. In this embodiment, as the plurality of second parts, for example, patterns of a plurality of connecting parts 37 and a plurality of bonding parts 39 are formed. Therefore, the manufacturing method of the thermal print head C1, like each manufacturing method of the thermal print head A1, uses a method that allows patterning of the plurality of second parts, which is difficult to pattern using screen printing, with higher definition than screen printing. pattern. Thereby, it is possible to form the electrode layer 3 in which the conduction path is appropriately configured.

In the method for manufacturing the thermal print head B1, patterning of a plurality of second parts is performed by sequentially performing a coating process (second coating process), a baking process (second baking process), and a partial removal process. . In the application step (second application step), the conductive paste 30C is applied to the second region 10B by screen printing to form a solid pattern on the entire surface of the second region 10B. In the firing step (second firing step), the conductive paste 30C in the solid pattern portion is fired to form a fired body of the conductive paste 30C. In the partial removal step, the solid pattern is partially removed by laser processing to form a plurality of second portion patterns. According to this configuration, a plurality of second portions can be patterned with higher definition than screen printing. Therefore, the plurality of second parts having a finer pattern shape than the plurality of first parts can be appropriately formed without causing short circuits or disconnections.

The method for manufacturing the thermal print head B1 includes a coating process and a baking process. In the application process, a first application process of applying the conductive paste 30C to the first region 10A and a second application process of applying the conductive paste 30C to the second region 10B are performed at once by screen printing. The firing step includes a first firing step of firing the conductive paste 30C in the first region 10A and a second firing step of firing the conductive paste 30C in the second region 10B. According to this configuration, the application and baking of the conductive paste 30C can be performed each at one time, which is preferable for improving manufacturing efficiency.

In the manufacturing method according to the second embodiment, the electrode layer forming step is not limited to the method described above. For example, the first coating step and the second coating step may be performed separately instead of all at once, and the first baking step and the second baking step may be performed separately instead of all at once. For example, the first coating step, first baking step, second coating step, second baking step, and partial removal step may be performed in this order. In this case, for example, a thermal print head B2 shown in FIG. 15 is formed. In the thermal print head B2 shown in FIG. 15, the first edge portion 37a of each connecting portion 37 is not formed integrally with each individual electrode strip portion 38, but is formed on each individual electrode strip portion 38. ing. Further, for example, the second coating step, the second baking step, the partial removal step, the first coating step, and the first baking step may be performed in this order. In this case, for example, a thermal print head B3 shown in FIG. 16 is formed. In the thermal print head B3 shown in FIG. 16, the first edge portion 37a of each connecting portion 37 is not formed integrally with each individual electrode strip portion 38, but is formed under each individual electrode strip portion 38. ing. That is, the first edge portion 37a of each connecting portion 37 is interposed between each individual electrode strip portion 38 and the glass layer 122 (substrate 1).

<Third embodiment>
17 and 18 show a thermal print head C1 according to a third embodiment. FIG. 17 is a plan view showing the thermal print head C1, and corresponds to the enlarged plan view of the main part in FIG. FIG. 18 is a sectional view taken along the line XVIII-XVIII in FIG. 17, and corresponds to the enlarged sectional view of the main part in FIG.

As shown in FIGS. 17 and 18, the thermal print head C1 differs from the thermal print heads A1 and B1 in the structure of the electrode layer 3.

As shown in FIG. 18, in the electrode layer 3 of the thermal print head C1, each individual electrode 36 has a connecting portion 37 formed separately from the individual electrode strip portion 38 and integrally formed with a bonding portion 39. There is. The first edge portion 37a of each connecting portion 37 overlaps each individual electrode strip portion 38 when viewed in the thickness direction z, and is located between each individual electrode strip portion 38 and the glass layer 122 (substrate 1). do. The second end edge portion 37b of each connecting portion 37 does not overlap the bonding portion 39 when viewed in the thickness direction z.

In this embodiment, the plurality of common electrode strips 34 (common electrodes 33) and the plurality of individual electrode strips 38 (the plurality of individual electrodes 36) of the electrode layer 3 are located in the first region 10A of the substrate 1. It is formed. Further, in the electrode layer 3, the plurality of connecting portions 37 (the plurality of individual electrodes 36) and the plurality of bonding portions 39 (the plurality of individual electrodes 36) are formed in the second region 10B of the substrate 1. In this embodiment, the plurality of common electrode strip portions 34 and the plurality of individual electrode strip portions 38 each correspond to “a plurality of first portions” as described in the claims. Further, the plurality of connecting portions 37 correspond to "the plurality of second parts" described in the claims.

An example of a method for manufacturing the thermal print head C1 will be described with reference to FIGS. 19 to 25. 19, FIG. 22, and FIG. 24 are plan views showing one step of the method for manufacturing the thermal print head C1, and correspond to the enlarged plan view of the main part in FIG. 17. 20, FIG. 21, FIG. 23, and FIG. 25 are cross-sectional views showing one step of the method for manufacturing the thermal print head C1, and correspond to the enlarged cross-sectional view of the main part of FIG. 4. 20 shows a cross section along line XX-XX in FIG. 19, FIG. 23 shows a cross section along line XXIII-XXIII in FIG. 22, and FIG. 25 shows a cross section along line XXV-XXV in FIG. .

The method for manufacturing the thermal print head C1 differs from the methods for manufacturing the thermal print heads A1 and B1 in the electrode layer forming process. The electrode layer forming process in this embodiment includes a preceding coating process, a stamping process, a preceding baking process, a partial removal process, a subsequent coating process, and a subsequent coating process.

In the electrode layer forming step in this embodiment, a preliminary coating step is first performed. In the advance coating step, the conductive paste 30B is applied to the second region 10B of the substrate 1 prepared in the substrate preparation step. The preliminary coating step is performed by screen printing, and as shown in FIGS. 19 and 20, a solid pattern is formed on the entire surface of the second region 10B.

Next, a stamping process is performed. In the stamping process, as shown in FIG. 21, an imprint mold 91 having a concavo-convex pattern is brought into contact with and pressurized the conductive paste 30B applied in the preceding coating process. Then, by releasing the pressure on the imprint mold 91, a thick portion 311 and a thin portion 312 are formed in the conductive paste 30B, as shown in FIGS. 22 and 23.

Next, a preliminary firing step is performed. In the preliminary firing step, the conductive paste 30B including the thick portion 311 and the thin portion 312 is fired. As a result, a fired body of conductive paste 30B is formed. A step of drying the conductive paste 30B may be further added between the stamping step and the preliminary firing step.

Next, a partial removal step is performed. In the partial removal step, as shown in FIGS. 24 and 25, by etching, for example, the thin portion 312 is removed leaving the thick portion 311. In this embodiment, the etching is performed on the entire surface, and the dimension of the thick portion 311 in the thickness direction z is also reduced. Note that a mask may be formed on the thick portion 311 to prevent the thick portion 311 from becoming thin. The partial removal step is not limited to etching, and the thin portion 312 may be removed by blasting, for example. Thereby, as shown in FIGS. 24 and 25, a plurality of connecting portions 37 and a plurality of bonding portions 39 are formed. Therefore, a pattern of a plurality of connecting portions 37 and a plurality of bonding portions 39 (a plurality of second portions) is formed by the partial removal process.

Next, a subsequent coating step is performed. In the subsequent coating step, a conductive paste 30A is applied to the first region 10A of the substrate 1. In the subsequent application step, the conductive paste 30A is applied by screen printing in a pattern shown by imaginary lines in FIG. The pattern shown by imaginary lines in FIG. 24 has substantially the same shape as the pattern of the plurality of common electrode strips 34 and connecting portions 35 and the plurality of individual electrode strips 38. Therefore, in the subsequent coating step, patterning of the plurality of common electrode strips 34 and the plurality of individual electrode strips 38 (the plurality of first parts) is performed.

Next, a subsequent firing step is performed. In the subsequent firing step, the conductive paste 30A is fired to form a plurality of common electrode strips 34 and connecting portions 35 (common electrodes 33), and a plurality of individual electrode strips 38. A step of drying the conductive paste 30A may be further added between the subsequent coating step and the subsequent firing step.

In this embodiment, the subsequent coating process corresponds to the "first patterning process" described in the claims, and the subsequent baking process corresponds to the "first baking process" described in the claims. . The preceding coating step corresponds to the "coating step" described in the claims, and the preceding firing step corresponds to the "second firing step" described in the claims. Further, the combined process of the preliminary coating process, stamping process, preliminary baking process, and partial removal process corresponds to the "second patterning process" described in the claims.

After that, the thermal print head C1 is manufactured by performing a resistor layer forming process, a protective layer forming process, and an assembly process similarly to each manufacturing method according to the first embodiment and the second embodiment.

The functions and effects of the method for manufacturing the thermal print head C1 are as follows.

The method for manufacturing the thermal print head C1 includes an electrode layer forming step including a first patterning step and a second patterning step, similar to the method for manufacturing the thermal print heads A1 and B1. In the first patterning step, a plurality of first part patterns are formed by screen printing. In this embodiment, for example, a plurality of common electrode strip portions 34 and a plurality of individual electrode strip portions 38 are formed as the plurality of first portions. In the second patterning step, a plurality of second part patterns are formed using a method that allows patterning with higher definition than screen printing. In this embodiment, as the plurality of second parts, for example, patterns of a plurality of connecting parts 37 and a plurality of bonding parts 39 are formed. Therefore, the method for manufacturing the thermal print head C1, like the methods for manufacturing the thermal print heads A1 and B1, is capable of patterning the plurality of second parts, which are difficult to pattern using screen printing, with higher definition than screen printing. Patterning is done using a method. Thereby, it is possible to form the electrode layer 3 in which the conduction path is appropriately configured.

In the method for manufacturing the thermal print head C1, patterning of a plurality of second parts is performed by sequentially performing a preliminary coating process, a stamping process, a preliminary baking process, and a partial removal process. In the preliminary application step, the conductive paste 30B is applied to the second region 10B by screen printing to form a solid pattern on the entire surface of the second region 10B. In the stamping process, a solid pattern of the conductive paste 30B is pressed by an imprint mold 91 to form a thick portion 311 and a thin portion 312 in the conductive paste 30B. In the preliminary firing step, the conductive paste 30B including the thick portion 311 and the thin portion 312 is fired to form a fired body of the conductive paste 30B. In the partial removal step, a plurality of second portion patterns are formed by removing the thin portion 312 while leaving the thick portion 311 by etching, for example. According to this configuration, a plurality of second portions can be patterned with higher definition than screen printing. Therefore, the plurality of second parts having a finer pattern shape than the plurality of first parts can be appropriately formed without causing short circuits or disconnections.

In the manufacturing method according to the third embodiment, the electrode layer forming step is not limited to the method described above, and the electrode layer 3 may be formed by the following step. For example, the preceding coating process and the subsequent coating process are performed at once. At this time, the conductive paste 30A applied in the preceding application process and the conductive paste 30B applied in the subsequent application process are integrated. Thereafter, a stamping process is performed to form a thick portion 311 and a thin portion 312 in the conductive paste 30B formed in the second region 10B. Then, the preceding firing step and the subsequent firing step are performed at the same time, the conductive pastes 30A and 30B are fired at the same time, and the thin portion 312 is removed in the partial removal step. Thereby, the electrode layer 3 may be formed. In this case, the first edge portion 37a of each connecting portion 37 is not formed under each individual electrode strip 38, but is formed integrally with each individual electrode strip 38. For example, the order of the preceding coating process and the subsequent coating process may be changed to form a plurality of first parts (such as a plurality of individual electrode strips 38), and then a plurality of second parts (such as a plurality of connecting parts 37). etc.) may be formed. That is, after applying the conductive paste 30A to the first region 10A by screen printing, the conductive paste 30A is fired. Then, a solid pattern of conductive paste 30B is applied to the second region 10B by screen printing, and a stamping process is performed. Thereafter, the conductive paste 30B after the stamping process is fired, and a partial removal process is performed. Thereby, the electrode layer 3 may be formed. In this case, the first edge portion 37a of each connecting portion 37 is not formed under each individual electrode strip 38 but on top of each individual electrode strip 38.

In the first to third embodiments, the first covering portion 51 of the protective layer 5 includes the raised portion 511, but the present invention is not limited thereto. For example, as shown in FIG. 26, the first covering portion 51 may not include the raised portion 511. FIG. 26 is an enlarged sectional view of a main part of a thermal print head according to such a modification, and corresponds to the cross section shown in FIG. 4. For example, the thermal print head shown in FIG. 26 can be manufactured depending on the viscosity of the glass paste constituting the protective layer 5 used in the protective layer forming step and the firing conditions for this glass paste.

The method for manufacturing a thermal print head and the thermal print head according to the present disclosure are not limited to the embodiments described above. The specific processing of each step of the method for manufacturing a thermal print head of the present disclosure and the specific configuration of each part of the thermal print head can be variously changed in design.

The thermal print head manufacturing method and thermal print head according to the present disclosure include embodiments related to the following additional notes.
[Additional note 1]
a substrate preparation step for preparing a substrate;
a resistor layer forming step of forming a resistor layer including a plurality of heat generating parts arranged in the main scanning direction on the substrate;
an electrode layer forming step of forming an electrode layer for energizing the resistor layer;
It contains
The electrode layer includes a plurality of first parts arranged with a first pitch width, and a plurality of second parts arranged with a second pitch width smaller than the first pitch width,
The substrate has a first region where the plurality of first portions are formed when viewed in the thickness direction of the substrate, and a second region where the plurality of second portions are formed when viewed in the thickness direction. including,
The electrode layer forming step includes:
a first patterning step of forming the plurality of first part patterns in the first region by screen printing;
a second patterning step of forming the plurality of second portion patterns in the second region by a patterning method that allows patterning with higher definition than the screen printing;
A method for manufacturing a thermal print head, comprising:
[Additional note 2]
The electrode layer further includes a plurality of bonding parts each connected to a driving IC via a wire,
The plurality of second parts are each connected to each of the plurality of bonding parts, and are arranged between the plurality of bonding parts and the plurality of first parts when viewed in the thickness direction. ,
The method for manufacturing a thermal print head according to appendix 1, wherein each of the plurality of first parts partially overlaps the resistor layer when viewed in the thickness direction.
[Additional note 3]
Manufacturing the thermal print head according to appendix 2, wherein each of the plurality of first parts and the plurality of second parts are arranged in the main scanning direction, and each has a band shape extending along the sub-scanning direction. Method.
[Additional note 4]
The method for manufacturing a thermal print head according to appendix 3, wherein the second pitch width is 10 μm or more and 100 μm or less.
[Additional note 5]
Each dimension of the plurality of second parts in the main scanning direction is 10 μm or more and 100 μm or less,
The method for manufacturing a thermal print head according to appendix 4, wherein the distance between two adjacent second parts in the main scanning direction is 10 μm or more and 100 μm or less.
[Additional note 6]
The electrode layer forming step further includes a first firing step,
The first patterning step includes screen printing a conductive paste on the first region in the shape of the plurality of first part patterns;
The thermal print head according to any one of Supplementary Notes 2 to 5, wherein the first baking step forms the plurality of first parts by baking the conductive paste printed in the first patterning step. manufacturing method.
[Additional note 7]
The electrode layer forming step further includes a second firing step,
In the second patterning step, a conductive paste is dispensed onto the second region in the shape of the plurality of second portion patterns;
The method for manufacturing a thermal print head according to appendix 6, wherein the second firing step forms the plurality of second parts by firing the conductive paste applied in the second patterning step.
[Additional note 8]
The first patterning step further includes forming a pattern of the plurality of bonding parts in the first region,
Each of the plurality of first parts is connected to each of the plurality of second parts,
Each of the plurality of second parts includes a first edge part, a second edge part, and an intermediate part,
The intermediate portion connects the first edge portion and the second edge portion,
The first edge portion overlaps each of the plurality of bonding portions when viewed in the thickness direction,
The method for manufacturing a thermal print head according to appendix 7, wherein the second edge portion overlaps each of the plurality of first portions when viewed in the thickness direction.
[Additional note 9]
The second patterning step includes:
a coating step of applying a conductive paste to the second region by screen printing to form a solid pattern;
a partial removal step of partially removing the solid pattern by laser processing;
including;
The method for manufacturing a thermal print head according to appendix 6, wherein the solid pattern is shaped into the shape of the plurality of second portion patterns by the partial removal step.
[Additional note 10]
The second patterning step includes:
The method for manufacturing a thermal print head according to appendix 9, further comprising a second firing step of firing the solid pattern between the coating step and the partial removal step.
[Additional note 11]
Screen printing of the first patterning step and screen printing of the coating step are performed at once,
The method for manufacturing a thermal print head according to appendix 10, wherein the firing in the first firing step and the firing in the second firing step are performed at once.
[Additional note 12]
The second patterning step includes:
a coating step of applying a conductive paste to the second region by screen printing to form a solid pattern;
a stamping step of forming a thick portion and a thin portion on the solid pattern by bringing an imprint mold having a concavo-convex pattern into contact with the solid pattern and applying pressure;
a partial removal step of removing the thin wall portion while leaving the thick wall portion;
including;
The method for manufacturing a thermal print head according to appendix 6, wherein the solid pattern is shaped into the plurality of second portion patterns by the stamping step and the partial removal step.
[Additional note 13]
The second patterning step includes:
The method for manufacturing a thermal print head according to appendix 12, further comprising a second firing step of firing the solid pattern between the stamping step and the partial removal step.
[Additional note 14]
The method for manufacturing a thermal print head according to any one of Appendix 12 and 13, wherein in the partial removal step, the thin portion is removed by etching or blasting.
[Additional note 15]
The substrate preparation step includes:
a base material preparation step of preparing a base material having a main surface facing one side in the thickness direction;
further comprising a glaze layer forming step of forming a glaze layer on the main surface,
The glaze layer forming step is performed after the base material preparation step and before each of the resistor layer forming step and the electrode layer forming step,
The method for manufacturing a thermal print head according to any one of appendices 1 to 14, wherein in the resistor layer forming step, the resistor layer is formed on the glaze layer.
[Additional note 16]
The glaze layer includes a partial glaze raised from the main surface in the thickness direction,
The method for manufacturing a thermal print head according to appendix 15, wherein the plurality of heat generating parts are formed on the partial glaze.
[Additional note 17]
The method for manufacturing a thermal print head according to any one of Supplementary notes 1 to 16, further comprising a protective layer forming step of forming a protective layer covering the resistor layer and the electrode layer.
[Additional note 18]
A substrate and
a resistor layer formed on the substrate and including a plurality of heat generating parts arranged in the main scanning direction;
an electrode layer for energizing the resistor layer;
It contains
The electrode layer includes a plurality of first parts, a plurality of second parts, and a plurality of bonding parts,
The plurality of first parts each have a band shape extending in the sub-scanning direction, and are arranged in the main-scanning direction with a first pitch width,
The plurality of second parts each have a band shape extending in the sub-scanning direction, and are arranged in the main-scanning direction with a second pitch width smaller than the first pitch width,
Each of the plurality of bonding parts is connected to a drive IC via a wire, and each of the plurality of bonding parts is connected to each of the plurality of second parts,
The plurality of first parts are patterned by screen printing,
The thermal print head is characterized in that the plurality of second parts are patterned by a method that allows patterning with higher definition than the screen printing.
[Additional note 19]
The thermal print head according to appendix 18, wherein each edge of the plurality of first parts extending in the sub-scanning direction and each edge of the plurality of second parts extending in the sub-scanning direction have different linearity.
[Additional note 20]
Each of the plurality of first parts is connected to each of the plurality of second parts,
Each of the plurality of second parts includes a first edge part, a second edge part, and an intermediate part,
The intermediate portion connects the first edge portion and the second edge portion,
The first edge portion overlaps each of the plurality of bonding portions when viewed in the thickness direction of the substrate,
The thermal print head according to appendix 18 or 19, wherein the second edge portion overlaps the plurality of first portions when viewed in the thickness direction.

A1, A2, B1, B2, B3, C1: Thermal print head 1: Substrate 10A: First region 10B: Second region 11: Base material 11a: Main surface 12: Glaze layer 121: Partial glaze 122: Glass layer 3: Electrode layer 33 : Common electrode 34 : Common electrode strip part 341 : Base part 342 : Extension part 35 : Connection part 36 : Individual electrode 37 : Connection part 37a : First edge part 37b : Second edge part 37c : Intermediate part 371: Parallel portion 371B: Thin wire portion 372: Diagonal portion 38: Individual electrode strip portion 381: Base portion 382: Extension portion 39: Bonding portion 39A: First bonding portion 39B: Second bonding portion 30A, 30B, 30C: Conductive Paste 311 : Thick part 312 : Thin part 4 : Resistor layer 41 : Heat generating part 5 : Protective layer 51 : First covering part 511 : Raised part 52 : Second covering part 61 : Wire 71 : Drive IC
72: Sealing resin 73: Connector 74: Wiring board 75: Heat dissipation member 81: Platen roller 82: Printing medium 91: Imprint mold

Claims (16)

a substrate preparation step for preparing a substrate;
a resistor layer forming step of forming a resistor layer including a plurality of heat generating parts arranged in the main scanning direction on the substrate;
an electrode layer forming step of forming an electrode layer for energizing the resistor layer;
It contains
The electrode layer includes a plurality of first parts arranged with a first pitch width, and a plurality of second parts arranged with a second pitch width smaller than the first pitch width,
The substrate has a first region where the plurality of first portions are formed when viewed in the thickness direction of the substrate, and a second region where the plurality of second portions are formed when viewed in the thickness direction. including,
The electrode layer forming step includes:
a first patterning step of forming the plurality of first part patterns in the first region by screen printing;
a second patterning step of forming the plurality of second portion patterns in the second region by a patterning method that allows patterning with higher definition than the screen printing;
including;
Each of the plurality of first parts is connected to each of the plurality of second parts,
The line width of each of the plurality of second parts is smaller than the line width of each of the plurality of first parts.
A method for manufacturing a thermal print head, characterized in that: The electrode layer further includes a plurality of bonding parts each connected to a driving IC via a wire,
The plurality of second parts are each connected to each of the plurality of bonding parts, and are arranged between the plurality of bonding parts and the plurality of first parts when viewed in the thickness direction. ,
Each of the plurality of first parts partially overlaps the resistor layer when viewed in the thickness direction.
A method for manufacturing a thermal print head according to claim 1. The plurality of first parts and the plurality of second parts are each arranged in the main scanning direction, and each has a band shape extending along the sub-scanning direction.
A method for manufacturing a thermal print head according to claim 2. The second pitch width is greater than 10 μm and less than 100 μm,
A method for manufacturing a thermal print head according to claim 3. Each dimension of the plurality of second parts in the main scanning direction is 10 μm or more and 100 μm or less,
The distance between two adjacent second parts in the main scanning direction is 10 μm or more and less than 100 μm.
A method for manufacturing a thermal print head according to claim 4. The electrode layer forming step further includes a first firing step,
The first patterning step includes screen printing a conductive paste on the first region in the shape of the plurality of first part patterns;
In the first firing step, the plurality of first parts are formed by firing the conductive paste printed in the first patterning step.
A method for manufacturing a thermal print head according to any one of claims 2 to 5. The electrode layer forming step further includes a second firing step,
In the second patterning step, a conductive paste is dispensed onto the second region in the shape of the plurality of second portion patterns;
In the second firing step, the plurality of second parts are formed by firing the conductive paste applied in the second patterning step.
A method for manufacturing a thermal print head according to claim 6. The first patterning step further includes forming a pattern of the plurality of bonding parts in the first region ,
Each of the plurality of second parts includes a first edge part, a second edge part, and an intermediate part,
The intermediate portion connects the first edge portion and the second edge portion,
The first edge portion overlaps each of the plurality of bonding portions when viewed in the thickness direction,
The second edge portion overlaps each of the plurality of first portions when viewed in the thickness direction,
A method for manufacturing a thermal print head according to claim 7. a substrate preparation step for preparing a substrate;
a resistor layer forming step of forming a resistor layer including a plurality of heat generating parts arranged in the main scanning direction on the substrate;
an electrode layer forming step of forming an electrode layer for energizing the resistor layer;
It contains
The electrode layer includes a plurality of first parts arranged with a first pitch width, and a plurality of second parts arranged with a second pitch width smaller than the first pitch width,
The substrate has a first region where the plurality of first portions are formed when viewed in the thickness direction of the substrate, and a second region where the plurality of second portions are formed when viewed in the thickness direction. including,
The electrode layer forming step includes:
a first patterning step of forming the plurality of first part patterns in the first region by screen printing;
a second patterning step of forming the plurality of second portion patterns in the second region by a patterning method that allows patterning with higher definition than the screen printing;
including;
The electrode layer further includes a plurality of bonding parts each connected to a driving IC via a wire,
The plurality of second parts are each connected to each of the plurality of bonding parts, and are arranged between the plurality of bonding parts and the plurality of first parts when viewed in the thickness direction. ,
Each of the plurality of first parts partially overlaps the resistor layer when viewed in the thickness direction,
The electrode layer forming step further includes a first firing step,
The first patterning step includes screen printing a conductive paste on the first region in the shape of the plurality of first part patterns;
In the first firing step, the plurality of first parts are formed by firing the conductive paste printed in the first patterning step,
The second patterning step includes:
a coating step of applying a conductive paste to the second region by screen printing to form a solid pattern;
a stamping step of forming a thick portion and a thin portion on the solid pattern by bringing an imprint mold having a concavo-convex pattern into contact with the solid pattern and applying pressure;
a partial removal step of removing the thin wall portion while leaving the thick wall portion;
including;
forming the solid pattern into the shape of the plurality of second portion patterns by the stamping step and the partial removal step ;
A method of manufacturing a thermal print head. The second patterning step includes:
Further comprising a second firing step of firing the solid pattern between the stamping step and the partial removal step.
A method for manufacturing a thermal print head according to claim 9 . In the partial removal step, the thin portion is removed by etching or blasting.
A method for manufacturing a thermal print head according to claim 9 or 10 . The substrate preparation step includes:
a base material preparation step of preparing a base material having a main surface facing one side in the thickness direction;
further comprising a glaze layer forming step of forming a glaze layer on the main surface,
The glaze layer forming step is performed after the base material preparation step and before each of the resistor layer forming step and the electrode layer forming step,
In the resistor layer forming step, the resistor layer is formed on the glaze layer,
A method for manufacturing a thermal print head according to any one of claims 1 to 11 . The glaze layer includes a partial glaze raised from the main surface in the thickness direction,
The plurality of heat generating parts are formed on the partial glaze,
A method for manufacturing a thermal print head according to claim 12 . The method for manufacturing a thermal print head according to any one of claims 1 to 13 , further comprising a protective layer forming step of forming a protective layer covering the resistor layer and the electrode layer. A substrate and
a resistor layer formed on the substrate and including a plurality of heat generating parts arranged in the main scanning direction;
an electrode layer for energizing the resistor layer;
It contains
The electrode layer includes a plurality of first parts, a plurality of second parts, and a plurality of bonding parts,
The plurality of first parts each have a band shape extending in the sub-scanning direction, and are arranged in the main-scanning direction with a first pitch width,
The plurality of second parts each have a band shape extending in the sub-scanning direction, and are arranged in the main-scanning direction with a second pitch width smaller than the first pitch width,
Each of the plurality of bonding parts is connected to a drive IC via a wire, and each of the plurality of bonding parts is connected to each of the plurality of second parts,
The plurality of first parts are patterned by screen printing,
The plurality of second parts are patterned by a method that allows patterning with higher definition than the screen printing,
Each of the plurality of first parts is connected to each of the plurality of second parts,
The line width of each of the plurality of second parts is smaller than the line width of each of the plurality of first parts.
A thermal print head characterized by: Each of the plurality of second parts includes a first edge part, a second edge part, and an intermediate part,
The intermediate portion connects the first edge portion and the second edge portion,
The first edge portion overlaps each of the plurality of bonding portions when viewed in the thickness direction of the substrate,
The second edge portion overlaps the plurality of first portions when viewed in the thickness direction,
The thermal print head according to claim 15 .

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