JPS61290068A - Edge-type thermal head - Google Patents
Edge-type thermal headInfo
- Publication number
- JPS61290068A JPS61290068A JP13258085A JP13258085A JPS61290068A JP S61290068 A JPS61290068 A JP S61290068A JP 13258085 A JP13258085 A JP 13258085A JP 13258085 A JP13258085 A JP 13258085A JP S61290068 A JPS61290068 A JP S61290068A
- Authority
- JP
- Japan
- Prior art keywords
- heating elements
- common
- substrate
- edge
- layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/315—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material
- B41J2/32—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material using thermal heads
- B41J2/345—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material using thermal heads characterised by the arrangement of resistors or conductors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/315—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material
- B41J2/32—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective application of heat to a heat sensitive printing or impression-transfer material using thermal heads
- B41J2/335—Structure of thermal heads
Landscapes
- Electronic Switches (AREA)
Abstract
Description
【発明の詳細な説明】
（発明の技術分野）
本発明はサーマルヘッド、特にエッヂ型サーマルヘッド
に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a thermal head, particularly an edge type thermal head.
（発明の背景）
ドツト状の発熱体を一直線上に配置した、いわゆるライ
ンタイプのサーマルヘッドとしては、発熱体を基板の端
部に配置した千ツヂ型と、基板中央部に配置したセンタ
型とがある。最近の傾向としては、エッチ型が主流とな
りつつある。その理由としては、ＩＣ（集積回路）の実
装密度が高くなる欠点はあるものの、
（１）全体として基板の幅が狭くなり、プリンタを小型
化できること、
（２）発熱体が端部にあるので、印字直後に印字結果を
操作者が確認しやすくなるようにプリンタを構成でき、
これにより記録紙の送りの無駄を少なくできること、等
を挙げることができる。(Background of the Invention) There are two types of so-called line-type thermal heads in which dot-shaped heating elements are arranged in a straight line: a zigzag type in which the heating elements are arranged at the edge of the board, and a center type in which the heating elements are arranged in the center of the board. There is. As a recent trend, the etch type is becoming mainstream. The reasons for this are that, although there are disadvantages to the higher packaging density of ICs (integrated circuits), (1) the overall width of the board is narrower, allowing the printer to be made more compact; and (2) the heating element is located at the edge. , the printer can be configured to make it easier for the operator to check the print results immediately after printing.
As a result, wasteful feeding of recording paper can be reduced.
第５図および第６図を参照するに、一般にサーマルヘッ
ドは、ドツト状の発熱体ｌとこれに通電するための一対
の電極２．３が必要であり、ラインタイプのサーマルヘ
ッドにおいては、一対の電極２．３のうち一方の電極２
を選択的に通電するための個別電極と呼び、他方の電極
３を共通電極と呼ぶ。そして−直線上に配列した発熱体
１群を境に一方の側に個別電極２を配置し、他方の側に
共通電極３を配置する。この共通電極３は各発熱体ドツ
トに接続される個別部３ａと全発熱体を共通化するだめ
の共通部３ｂとからなる。Referring to FIGS. 5 and 6, a thermal head generally requires a dot-shaped heating element L and a pair of electrodes 2.3 for energizing it. One of the electrodes 2.3
is called an individual electrode for selectively energizing, and the other electrode 3 is called a common electrode. Then, - the individual electrodes 2 are arranged on one side of the group of heating elements arranged in a straight line, and the common electrode 3 is arranged on the other side. This common electrode 3 consists of an individual part 3a connected to each heating element dot and a common part 3b for making all the heating elements common.
また、一般に発熱体１群が形成される基板４、例えばア
ルミナ基板は熱電導率が良すぎて発熱効率が低下するた
めに、基板４の上に蓄熱層５、例えばガラスグレーズ層
を設ける。この場合、蓄熱層５は発熱体下部及びその近
傍にのみ設ける部分タイプと基板全体に設ける全体タイ
プとがある。Further, since the substrate 4 on which the group of heating elements is formed, such as an alumina substrate, generally has too good thermal conductivity and its heat generation efficiency is reduced, a heat storage layer 5, such as a glass glaze layer, is provided on the substrate 4. In this case, there are two types of heat storage layer 5: a partial type where the heat storage layer 5 is provided only under and near the heating element, and a whole type where the heat storage layer 5 is provided on the entire substrate.
第５図および第６図は従来のニー、ヂ型サーマルヘッド
の一例を示し、基板４の周縁に沿って共通電極３の共通
部３ｂが配設されている。共通部３ｂから基板４内方に
は蓄熱層５としての部分グレーズ層５が設けられ、その
頂部近傍に複数個のドツト状発熱体ｌがグレーズ層５の
長手方向に一直線上に並設されている。各発熱体ｌは共
通電極３の個別部３ａに一端が接続され、他端が個別電
極２に接続され、個別電極２は複数の駆動回路６に接続
されている。5 and 6 show an example of a conventional knee-shaped thermal head, in which a common portion 3b of a common electrode 3 is disposed along the periphery of a substrate 4. FIG. A partial glaze layer 5 as a heat storage layer 5 is provided inside the substrate 4 from the common portion 3b, and a plurality of dot-shaped heating elements l are arranged in a straight line in the longitudinal direction of the glaze layer 5 near the top of the partial glaze layer 5. There is. One end of each heating element l is connected to the individual portion 3a of the common electrode 3, the other end is connected to the individual electrode 2, and the individual electrode 2 is connected to a plurality of drive circuits 6.
共通部３ｂとしては発熱体ｌに比べて高い導伝率の金あ
るいはアルミニウムが使用されるが、共通部３ｂの全長
が長いため（例えば、Ａ４サイズ用のヘッドの場合、基
板４の長手方向の長さが約２１０ｍｍ）、中央部の発熱
体にとっては無視できない抵抗値を示す。そのため、不
所望の電圧降下が生じ、定電圧下で各発熱体を駆動して
も、側部の発熱体と中央部の発熱体とでは発熱量が異な
り、記録むらの原因となる。Gold or aluminum, which has higher conductivity than the heating element l, is used for the common part 3b, but since the total length of the common part 3b is long (for example, in the case of an A4 size head, the longitudinal direction of the substrate 4 is The length is approximately 210 mm), and the resistance value is not negligible for the central heating element. Therefore, an undesired voltage drop occurs, and even if each heating element is driven under a constant voltage, the amount of heat generated by the side heating element and the central heating element is different, which causes uneven recording.
そこで、この種従来のエッヂ型サーマルヘッドでは、共
通部３ｂの幅Ｗ（第５図参照）を広く設定し、かつ、共
通部３ｂの厚さＴ（第６図参照）を厚くして電圧降下を
抑制している。そのため。Therefore, in this type of conventional edge type thermal head, the width W (see Fig. 5) of the common part 3b is set wide, and the thickness T (see Fig. 6) of the common part 3b is increased to reduce the voltage drop. is suppressed. Therefore.
幅が広くなる分だけ発熱体１群が基板４の端部から内方
に離れ、前述したようなエッヂ型サーマルヘッド特有な
利点が損なわれてしまう。As the width increases, the group of heating elements moves inwardly from the edge of the substrate 4, and the advantages unique to the edge-type thermal head described above are lost.
（発明の目的）
本発明の目的は、このような従来の問題点を解消し、共
通電極の共通部での不所望な電圧降下を抑制しつつ、従
来よりも発熱体をより一層基板の端部に配置できるよう
にしたエッヂ型サーマルヘッドを提供することにある・
（発明の概要）
本発明は、基板の端部近傍に一直線上に配設されたドツ
ト状発熱体群の共通部の全体または一部を蓄熱層の下に
配設したことを特徴とする。(Objective of the Invention) An object of the present invention is to eliminate such conventional problems, to suppress undesirable voltage drop at the common portion of the common electrode, and to further position the heating element at the edge of the substrate than in the past. (Summary of the Invention) The present invention provides an edge-type thermal head that can be placed in a straight line near the edge of a substrate. Alternatively, a portion thereof is disposed under the heat storage layer.
（実施例）
第１図（ａ）および（ｂ）は本発明エッヂ型サーマルヘ
ッドの一実施例を示し、第１図（ａ）はその平面図、第
１図（ｂ）はそのＡ−Ａ線断面図である。(Embodiment) FIGS. 1(a) and 1(b) show an embodiment of the edge-type thermal head of the present invention, FIG. 1(a) is its top view, and FIG. 1(b) is its A-A. FIG.
第１図（ａ）および第１図（ｂ）を参照するに、符号４
はアルミナ基板であり、第２図および第３図に詳細に示
すように、基板４の周縁は略コ字状に幅７ｍｍの共通電
極３の共通部３ｂが配設され、更にその上には、蓄熱層
としての部分グレーズ層５がａ層されている。ここで、
部分グレーズ層５は共通部３ｂの縁から約２ｍｍずらし
て積層されている。部分グレーズ層５の頂部には複数個
の発熱体（薄膜抵抗体）１が所定の間隔で一直線−ヒに
並設されている。その間隔は、例えば、８ドツ）７ｍｍ
の記録解像度が得られるように決定される。各発熱体ｌ
からは個別部３ａが引き出されてそれぞれ共通部３ｂと
接続される。その個別部３ａと対向した位置には１個別
電極２が各発熱体ｌから引き出され１図示しない複数の
駆動回路とそれぞれの発熱体ｌが接続される。そして、
各発熱体１群上には保護膜７が被着されている。なお、
第１図（ａ）では保護膜７は省略しである。Referring to FIG. 1(a) and FIG. 1(b), reference numeral 4
is an alumina substrate, and as shown in detail in FIGS. 2 and 3, the periphery of the substrate 4 is provided with a common portion 3b of a common electrode 3 having a width of 7 mm in a substantially U-shape. , a partial glaze layer 5 as a heat storage layer is formed. here,
The partial glaze layer 5 is stacked so as to be offset by about 2 mm from the edge of the common portion 3b. On the top of the partial glaze layer 5, a plurality of heating elements (thin film resistors) 1 are arranged in a straight line at predetermined intervals. The interval is, for example, 8 dots) 7mm
is determined so as to obtain a recording resolution of . Each heating element
The individual portions 3a are pulled out and connected to the common portion 3b, respectively. One individual electrode 2 is drawn out from each heating element 1 at a position facing the individual portion 3a, and each heating element 1 is connected to a plurality of drive circuits (not shown). and,
A protective film 7 is deposited on each group of heating elements. In addition,
In FIG. 1(a), the protective film 7 is omitted.
すなわち、第１図（ｂ）かられかるように、基板４の周
縁に沿って配設された共通電極３のうち、発熱体に接続
される個別部３ａ以外の共通部３ｂが部分グレーズ層５
の下に配設されることになる。That is, as can be seen from FIG. 1(b), among the common electrodes 3 disposed along the periphery of the substrate 4, the common portions 3b other than the individual portions 3a connected to the heating element are covered with the partial glaze layer 5.
It will be placed under.
このように構成された本実施例のエッヂ型サーマルヘッ
ドの製造プロセスについて、第４図（ａ）〜（ｅ）を参
照して以下に説明する。The manufacturing process of the edge-type thermal head of this embodiment configured as described above will be described below with reference to FIGS. 4(a) to 4(e).
（ａ）まず、アルミナ基板４上に、スクリーン印刷によ
り厚膜金ペーストを共通部３ｂの形状に形成してその後
焼成した。(a) First, a thick film gold paste was formed on the alumina substrate 4 by screen printing in the shape of the common portion 3b, and then fired.
（ｂ）次に、共通部３ｂ上に、スクリーン印刷により厚
膜ガラスペーストを部分グレーズ層５の形状に形成して
その後焼成した。このとき、部分グレーズ層５を共通部
３ｂに対して幅方向に２ｍｍずらした。(b) Next, a thick film glass paste was formed in the shape of the partial glaze layer 5 by screen printing on the common portion 3b, and then fired. At this time, the partial glaze layer 5 was shifted by 2 mm in the width direction with respect to the common portion 3b.
（Ｃ）部分グレーズ層５の頂部に、スパッタ法により厚
さ約７０ＯＡの窒化タンタル膜を発熱体１として形成し
、通常のリングラフィ・エツチングにより、８ドツ）
／ ｍ ｍの密度でパターニングしてドツト状発熱体１
群を形成した。(C) On the top of the partial glaze layer 5, a tantalum nitride film with a thickness of about 70 OA is formed as a heating element 1 by sputtering, and 8 dots are formed by ordinary phosphorography and etching.
Dot-shaped heating element 1 is patterned with a density of / mm
formed a group.
（ｄ）個別部３ａ及び個別電極２として、厚さ５００Ａ
のニクロム層と厚さ１ｍｍの金層との二層を真空蒸着法
で蒸着してそれぞれ形成し、同様にリングラフィ昏エツ
チングにより所定の形状にパターニングした。(d) Thickness of 500A as individual part 3a and individual electrode 2
Two layers, a nichrome layer with a thickness of 1 mm and a gold layer with a thickness of 1 mm, were formed by vacuum evaporation, and similarly patterned into a predetermined shape by phosphorographic etching.
（ｅ）最後に、発熱体１群を中心として、保護膜７とし
て、厚さ２ｍｍの酸化シリコン層と厚さ５ｍｍの五酸化
タンタルとの二層構造をスパッタリングで形成した。(e) Finally, a two-layer structure of a silicon oxide layer with a thickness of 2 mm and a tantalum pentoxide layer with a thickness of 5 mm was formed as a protective film 7 by sputtering around the first group of heating elements.
以上のように、本実施例は、幅７ｍｍの共通部３ｂのう
ち５ｍｍを部分グレーズ層５の下にもぐり込ませたので
１発熱体１が並設されている位置を、従来に比べて基板
４の端部により近づけることができ、エッチ型サーマル
ヘッドの利点をより一層有効ならしめることができる。As described above, in this embodiment, 5 mm of the common portion 3b having a width of 7 mm is sunk under the partial glaze layer 5, so that the positions where the heating elements 1 are arranged side by side on the substrate are different from those in the conventional case. 4, and the advantages of the etch type thermal head can be made even more effective.
（発明の効果）
本発明によれば、エッヂ型サーマルヘッドの共通電極の
うち、発熱体に接続する個別部以外の共通部を蓄熱層の
下に配置したので、共通電極での電圧降下を抑制するた
めに共通電極の幅を広くしても発熱体の位置を基板端部
から遠ざける必要がなく、以って、本来エッヂ型サーマ
ルヘッドが持つ利点を損うことがない。(Effects of the Invention) According to the present invention, the common part of the common electrode of the edge type thermal head other than the individual part connected to the heating element is placed under the heat storage layer, so voltage drop at the common electrode is suppressed. Even if the width of the common electrode is widened in order to increase the width of the common electrode, there is no need to move the heating element away from the edge of the substrate, and the advantages inherent to the edge-type thermal head are not lost.
第１図（ａ）は本発明の一実施例を示す平面図、第１図
（ｂ）はそのＡ−Ａ線断面図、Ｗ４２図は第１図に示し
たエッヂ型サーマルヘッドの共通電極と部分グレーズ層
との位置関係を示す平面図、第３図はその拡大図、第４
図（ａ）〜（、ｅ）は第１図に示した工７ヂ型サーマル
ヘッドの製造プロセスを示すそれぞれ断面図、第５図は
従来のエッチ型サーマルヘッドの斜視概念図、第６図は
その縦断面図である。
に発熱体
２：個別電極
３：共通電極
３ａ：個別部
３ｂ＝共通部
４：基板
５：蓄熱層
７：保護膜
出 願 人 日本光学工業株式会社
代理人弁理士 永 井 冬 紀
第５図
１′：Ｊ
第６図
手続補正書
昭和６０年６月２４日
特許庁長官殿 ゛二昭和
８０年６月１８日付特許願（２）
２、発明の名称
エッヂ型サーマルヘッド
３、補正をする者
事件との関係 特許出願人
（４１１）日本光学工業株式会社
４、代理人
東京都新宿区西新宿７丁目６番５号
グローリア初穂生沼ビル７０３号
自発補正
６、補正により増加する発明の数 Ｏ７、補正の対
象
明細書の発明の詳細な説明の欄
８、補正の内容
（１）明細書第７頁第１０行の１ｍｍをｒｌｇｍＪと訂
正する。
（２）明細書第７頁第１５行の２ｍｍを「２舊ｍ」と訂
正する。
（３）明細書第７頁第１６行の５ｍｍをｒ５ＩＬｍＪと
訂正する。
紡ニFIG. 1(a) is a plan view showing an embodiment of the present invention, FIG. 1(b) is a sectional view taken along the line A-A, and FIG. 1(a) is a common electrode of the edge type thermal head shown in FIG. A plan view showing the positional relationship with the partial glaze layer, Fig. 3 is an enlarged view thereof, Fig. 4
Figures (a) to (e) are cross-sectional views showing the manufacturing process of the 7-dimensional thermal head shown in Figure 1, Figure 5 is a perspective conceptual diagram of a conventional etch-type thermal head, and Figure 6 is FIG. Heating element 2: Individual electrode 3: Common electrode 3a: Individual part 3b = Common part 4: Substrate 5: Heat storage layer 7: Protective film Applicant Nippon Kogaku Kogyo Co., Ltd. Representative patent attorney Fuyu Nagai Figure 5 1 ':J Figure 6 Procedural amendment June 24, 1985 Dear Commissioner of the Patent Office ゛2 Patent application dated June 18, 1985 (2) 2. Name of invention Edge-type thermal head 3. Case of person making amendment Relationship with Patent Applicant (411) Nippon Kogaku Kogyo Co., Ltd. 4, Agent Gloria Hatsuho Ionuma Building 703, 7-6-5 Nishi-Shinjuku, Shinjuku-ku, Tokyo Voluntary amendment 6, Number of inventions increased by amendment O7, Amendment Column 8 of Detailed Description of the Invention in the subject specification, details of amendment (1) 1 mm in line 10 of page 7 of the specification is corrected to rlgmJ. (2) 2 mm on page 7, line 15 of the specification is corrected to "2 mm." (3) 5mm on page 7, line 16 of the specification is corrected to r5ILmJ. spinning
Claims (1)
層表面に一直線上に配列されたドット状発熱体群と、各
発熱体に通電するための個別電極および共通電極とから
なるエッヂ型サーマルヘッドにおいて、前記共通電極の
共通部の全部または一部を前記蓄熱層と基板との間に配
置したことを特徴とするエッヂ型サーマルヘッド。An edge type consisting of a substrate having a heat storage layer on its surface, a group of dot-shaped heating elements arranged in a straight line on the surface of the heat storage layer near the end of the substrate, and individual electrodes and a common electrode for supplying electricity to each heating element. 1. An edge-type thermal head, wherein all or part of the common portion of the common electrode is disposed between the heat storage layer and the substrate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13258085A JPS61290068A (en) | 1985-06-18 | 1985-06-18 | Edge-type thermal head |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13258085A JPS61290068A (en) | 1985-06-18 | 1985-06-18 | Edge-type thermal head |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS61290068A true JPS61290068A (en) | 1986-12-20 |
Family
ID=15084650
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13258085A Pending JPS61290068A (en) | 1985-06-18 | 1985-06-18 | Edge-type thermal head |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61290068A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01275162A (en) * | 1988-04-28 | 1989-11-02 | Ngk Spark Plug Co Ltd | Manufacture of head for thermal printer |
| DE3917136A1 (en) * | 1988-05-27 | 1989-11-30 | Seiko Epson Corp | THERMAL PRINT HEAD |
| EP0395001A1 (en) * | 1989-04-26 | 1990-10-31 | Seiko Epson Corporation | Thermal print head and method of making same |
| US5032158A (en) * | 1988-03-02 | 1991-07-16 | E. I. Du Pont De Nemours And Company | Method of manufacturing thermal printer head |
-
1985
- 1985-06-18 JP JP13258085A patent/JPS61290068A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5032158A (en) * | 1988-03-02 | 1991-07-16 | E. I. Du Pont De Nemours And Company | Method of manufacturing thermal printer head |
| JPH01275162A (en) * | 1988-04-28 | 1989-11-02 | Ngk Spark Plug Co Ltd | Manufacture of head for thermal printer |
| DE3917136A1 (en) * | 1988-05-27 | 1989-11-30 | Seiko Epson Corp | THERMAL PRINT HEAD |
| US4973986A (en) * | 1988-05-27 | 1990-11-27 | Seiko Epson Corporation | Thermal print head |
| US5091736A (en) * | 1988-05-27 | 1992-02-25 | Seiko Epson Corporation | Thermal print head |
| EP0395001A1 (en) * | 1989-04-26 | 1990-10-31 | Seiko Epson Corporation | Thermal print head and method of making same |
| US5231420A (en) * | 1989-04-26 | 1993-07-27 | Seiko Epson Corporation | Thermal print head |
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