JP2563444B2 - Thermal head and manufacturing method thereof - Google Patents
Thermal head and manufacturing method thereofInfo
- Publication number
- JP2563444B2 JP2563444B2 JP4622888A JP4622888A JP2563444B2 JP 2563444 B2 JP2563444 B2 JP 2563444B2 JP 4622888 A JP4622888 A JP 4622888A JP 4622888 A JP4622888 A JP 4622888A JP 2563444 B2 JP2563444 B2 JP 2563444B2
- Authority
- JP
- Japan
- Prior art keywords
- resistor
- thermal head
- sectional area
- cross
- ratio
- 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.)
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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
- B41J2/335—Structure of thermal heads
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Description
【発明の詳細な説明】 産業上の利用分野 本発明はサーマルヘッド、特にペーストを印刷焼成し
て発熱抵抗体層などを構成する厚膜型のサーマルヘッド
およびその製造法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal head, and more particularly to a thick film type thermal head in which a heating resistor layer is formed by printing and firing a paste and a method for manufacturing the same.
従来の技術 サーマルヘッドは基板上の一方の電極と、この間の発
熱抵抗体層、この発熱抵抗体層の上に形成された耐摩耗
層とから基本的に構成され、従来は薄膜型と厚膜型とが
存在する。薄膜型は電極、発熱抵抗体層、耐摩耗層をス
パッタリング、蒸着などの真空プロセスにより形成した
ものである。厚膜型は例えば金メタルオルガニックペー
スト、RuO2−ガラスフリットペースト，ホウケイ酸ガラ
スフリットペースト、の印刷焼成により金電極、RuO2発
熱抵抗体層、耐摩耗層を得るもので、薄膜型より低コス
トで高性能サーマルヘッドを得ることができる。第５図
は得られたサーマルヘッドの断面図であり、アルミナグ
レーズ基板、ホーロ基板，などの絶縁基板20上に金電極
21,22、発熱抵抗体層23、耐摩耗層24が存在する。金電
極はフォトリソエッチング法によりパターニングされ
る。BACKGROUND ART A thermal head is basically composed of one electrode on a substrate, a heating resistor layer between them, and an abrasion resistant layer formed on this heating resistor layer. There are types and. The thin film type is one in which an electrode, a heating resistor layer, and an abrasion resistant layer are formed by a vacuum process such as sputtering or vapor deposition. The thick film type is a type that obtains a gold electrode, a RuO 2 heating resistor layer, and an abrasion resistant layer by printing and firing a gold metal organic paste, RuO 2 -glass frit paste, borosilicate glass frit paste, etc. A high-performance thermal head can be obtained at low cost. FIG. 5 is a sectional view of the obtained thermal head, in which a gold electrode is formed on an insulating substrate 20 such as an alumina glaze substrate or a hollow substrate.
There are 21, 22, a heating resistor layer 23, and a wear resistant layer 24. The gold electrode is patterned by the photolithographic etching method.
発明が解決しようとする問題点 上に述べたサーマルヘッドでの重要特性は（１）エネ
ルギ効率と（２）印字品質である。この二つの特性に対
して前記発熱抵抗体層や耐摩耗層中に存在する気泡が大
きく影響する。第１図は印字の時の様子を模式的に拡大
して示したものである。発熱抵抗体層１で発熱した熱エ
ネルギは、発熱抵抗体層１→耐摩耗層２→感熱紙３の様
に伝達されて印字される。４は絶縁基板、５は電極、６
はプラテンロールである。印字エネルギ効率および印字
品質はこの様な熱の伝達が抵抗体層から感熱紙へ効率良
く、なおかつ均一に行われるとき優れたものとなる。抵
抗体層中や耐摩耗層中に気泡が存在すると、印字エネル
ギ効率の低減や不均一印字などに至りヘッド特性の劣化
を来たす。すなわち抵抗体層１中に熱伝導率の悪い空気
層（気泡）７が存在すると感熱紙３への熱の流れ８が阻
止されたり、ヘッドの印字エネルギ効率が著しく悪くな
る。この傾向は内在する気泡の直径が電極間距離の1/5
以上、または抵抗体層の厚さの1/5以上のときに特に著
しく認められる。また第２図に示す様に、気泡11が個々
の抵抗体ドット12,13,14中に不均一に存在していると各
ドットにおける感熱紙への熱の伝達量がまちまちにな
り、この結果各印字ドットの印字濃度が異なったものに
なり印字品質が悪くなる。15は抵抗体、16は電極。この
ことは一つの印字ドットの中についても言えることであ
り、第３図に示すように印字ドットの形状が歪なものに
なって印字品質の劣化を来たす。例えば、第２図の電極
形状で正常な印字ドットパターンが17の時に18のように
なる。Problems to be Solved by the Invention The important characteristics of the thermal head described above are (1) energy efficiency and (2) print quality. Bubbles present in the heat generating resistor layer and the wear resistant layer have a great influence on these two characteristics. FIG. 1 is a schematic enlarged view showing a state of printing. The heat energy generated in the heating resistor layer 1 is transferred and printed in the order of the heating resistor layer 1 → the abrasion resistant layer 2 → the thermal paper 3. 4 is an insulating substrate, 5 is an electrode, 6
Is a platen roll. Printing energy efficiency and printing quality are excellent when such heat transfer is efficiently and uniformly carried out from the resistor layer to the thermal paper. The presence of air bubbles in the resistor layer or the abrasion resistant layer leads to a reduction in printing energy efficiency, non-uniform printing, etc., leading to deterioration in head characteristics. That is, when an air layer (air bubble) 7 having a poor thermal conductivity is present in the resistor layer 1, the flow 8 of heat to the thermal paper 3 is blocked or the print energy efficiency of the head is significantly deteriorated. The tendency is that the diameter of the internal bubbles is 1/5 of the distance between the electrodes.
This is particularly noticeable when the thickness of the resistor layer is 1/5 or more or more. Further, as shown in FIG. 2, if the bubbles 11 are non-uniformly present in the individual resistor dots 12, 13, 14, the amount of heat transfer to the thermal paper in each dot will be different, and as a result, The print density of each print dot is different and the print quality is poor. 15 is a resistor and 16 is an electrode. This can be said even for one print dot, and as shown in FIG. 3, the shape of the print dot becomes distorted and the print quality deteriorates. For example, when the normal dot pattern is 17 in the electrode shape shown in FIG.
課題を解決するための手段 本発明は、このようなサーマルヘッドの熱効率および
印字品質を改善するもので、気泡含有量の少ない抵抗体
層を発熱体としたサーマルヘッドである。すなわち、発
熱抵抗体の任意の断面の空隙部の断面積の全断面積に占
める比率を0.5以下としたサーマルヘッドである。ま
た、本発明のサーマルヘッドは、発熱抵抗体に内在する
気泡が個々の抵抗体ドット内及び抵抗体ドット間に均一
に分散して存在することを特徴とする。Means for Solving the Problems The present invention is to improve the thermal efficiency and print quality of such a thermal head, and is a thermal head using a resistor layer having a small bubble content as a heating element. That is, it is a thermal head in which the ratio of the cross-sectional area of the void of any cross section of the heating resistor to the total cross-sectional area is 0.5 or less. Further, the thermal head of the present invention is characterized in that the bubbles existing in the heating resistor are uniformly dispersed in the individual resistor dots and between the resistor dots.
さらに、本発明のサーマルヘッドの製造法は、発熱低
抗体を形成する抵抗体ペーストの焼成を、徐昇温、徐冷
却の焼成パターンで行うもので、特に、前記の焼成を、
少なくともペースト中の有機バインダの分解温度または
気化温度まで５℃/min以下の昇温速度で行うことが好ま
しい。Furthermore, the method for manufacturing a thermal head of the present invention is to perform firing of a resistor paste that forms an exothermic low antibody in a firing pattern of gradual temperature increase and gradual cooling.
It is preferable to perform at least the decomposition temperature or vaporization temperature of the organic binder in the paste at a heating rate of 5 ° C./min or less.
作用 本発明によれば抵抗体層で発熱した熱エネルギが効率
良く、かつドット間での差が少なく均一に感熱紙に伝わ
る高効率，高印字品質のサーマルヘッドを得ることがで
きる。Effects According to the present invention, it is possible to obtain a high-efficiency, high-printing-quality thermal head in which the heat energy generated in the resistor layer is efficiently transmitted and the difference between dots is uniformly transmitted to the thermal paper.
実 施 例 以下に本発明の具体的な実施例を示す。EXAMPLES Specific examples of the present invention will be described below.
（実施例１） ホーロ基板（厚さ1mm）の上に金のレジネートペース
トの印刷焼成、およびホトリソエッチング法により電極
パターン（１μｍ）を形成する。平均粒径0.1μｍの酸
化ルテニウム粉末40重量％、硼珪酸ガラスフリット60重
量％と有機バインダ、溶媒とからなる抵抗ペーストで20
0μｍ幅の抵抗体を印刷する。次にこれを１℃/minの昇
温速度で350℃まで加熱し、さらにこの温度で１時間保
持する。引続き10℃/minの速度で800℃まで昇温しこの
温度で10min間保持する。降温は10℃/minで室温まで行
う。第４図ａは本実施例で用いた焼成温度パターンであ
る。この様にして形成された抵抗体層の上に鉛系ガラス
の耐摩耗層を形成する。Example 1 An electrode pattern (1 μm) is formed on a holo substrate (thickness: 1 mm) by printing and firing a gold resinate paste and a photolithographic etching method. A resistance paste consisting of 40% by weight of ruthenium oxide powder with an average particle size of 0.1 μm, 60% by weight of borosilicate glass frit, an organic binder and a solvent.
Print a 0 μm wide resistor. Next, this is heated to 350 ° C. at a temperature rising rate of 1 ° C./min, and further held at this temperature for 1 hour. Subsequently, the temperature is raised to 800 ° C at a rate of 10 ° C / min and kept at this temperature for 10 min. Cool down to room temperature at 10 ℃ / min. FIG. 4a is a firing temperature pattern used in this example. A wear resistant layer of lead-based glass is formed on the resistor layer thus formed.
（実施例２） 実施例１と同じ要領で抵抗ペーストの印刷を行う。(Example 2) The resistance paste is printed in the same manner as in Example 1.
続いて１℃/minで800℃まで昇温しこの温度で10min保
持する。降温は10℃/minで室温まで行う。耐摩耗層も実
施例１と同じく形成する。本実施例の抵抗体層形成のの
焼成パターンを第４図ｂに示す。Then, the temperature is raised to 800 ° C. at 1 ° C./min and kept at this temperature for 10 min. Cool down to room temperature at 10 ℃ / min. The abrasion resistant layer is also formed as in Example 1. The firing pattern for forming the resistor layer of this example is shown in FIG. 4b.
（実施例３） 実施例２と同じ昇温パターンに続いて１℃/minの速度
で室温まで降温する。焼成パターンは、第４図ｃに示
す。(Example 3) Following the same heating pattern as in Example 2, the temperature is lowered to room temperature at a rate of 1 ° C / min. The firing pattern is shown in Figure 4c.
（実施例４） 昇温を50℃/minで室温から800℃まで行い800℃で10mi
n保持する。続いて１℃/minの速度で室温まで降温す
る。焼成パターンを第４図ｄに示す。(Example 4) The temperature was raised from room temperature to 800 ° C at 50 ° C / min and 10 mi at 800 ° C.
n hold. Then, the temperature is lowered to room temperature at a rate of 1 ° C./min. The firing pattern is shown in Figure 4d.
（実施例５） 昇温を１℃/min室温から800℃まで行い800℃で10min
保持し、続いて１℃/minの速度で室温まで降温する。(Example 5) The temperature was raised from room temperature to 800 ° C at 1 ° C / min and 800 ° C for 10 min.
Hold and then cool to room temperature at a rate of 1 ° C / min.
（実施例６） 酸化ルテニウム粉末（平均粒径１μｍ）30重量％と硼
珪酸ガラスフリット50重量％と酸化ジルコニウム（平均
粒径0.05μｍ）の混合物に有機バインダおよび希釈溶剤
を加えて抵抗体ペーストとする。これを印刷し実施例１
と同じ要領および焼成パターンでサーマルヘッドとす
る。Example 6 An organic binder and a diluting solvent were added to a mixture of 30% by weight of ruthenium oxide powder (average particle size 1 μm), 50% by weight of borosilicate glass frit and zirconium oxide (average particle size 0.05 μm) to form a resistor paste. To do. Printing this, Example 1
Use a thermal head with the same procedure and firing pattern.
（比較例） 実施例１で用いたものと同じペーストを印刷し50℃/m
inの昇温および降温速度で焼成する。最高保持温度は80
0℃である。この例では連続トンネル焼成炉を用いた。(Comparative Example) The same paste as used in Example 1 was printed and printed at 50 ° C / m.
Baking is performed at an in-temperature rising and falling rate. Maximum holding temperature is 80
It is 0 ° C. In this example, a continuous tunnel firing furnace was used.
表に本発明の実施例および比較例の抵抗体層の特徴及
びこの抵抗体層を有するサーマルヘッドの特性を掲げ
る。この表の中の気泡の分散度、含有量、直径等は、以
下の方法で測定した。すなわち抵抗体の任意の断面を顕
微鏡によって画像電気信号としてとりこみ、これを空隙
部と非空隙部とで白黒２値化する。このときのしきい値
は実画像から判定する。ここで白／黒比率から空隙部の
比率を気泡率とした。また発熱抵抗体の任意の断面を直
交座標によりＸ−Ｙ画素に区分し、Xn−Yn画素が空隙部
である確率をＣとした。この値は気泡の均一分散度に相
当する。また、抵抗体の任意のドットの任意の断面の空
隙部の断面積の全断面積に占める比率Ａと、他の任意の
低抗体ドットの任意の断面の空隙部の断面積の全断面積
に占める比率Ｂとの比率A/BをＤとした。この値は抵抗
体ドット間の気泡の均一分散度の指標となる。The table shows the characteristics of the resistor layers of the examples and comparative examples of the present invention and the characteristics of the thermal head having the resistor layers. The degree of dispersion, content, diameter, etc. of bubbles in this table were measured by the following methods. That is, an arbitrary cross section of the resistor is taken in as an image electrical signal by a microscope, and this is binarized in a void portion and a non-void portion. The threshold value at this time is determined from the actual image. Here, the ratio of voids was defined as the bubble ratio from the white / black ratio. Further, an arbitrary cross section of the heating resistor is divided into XY pixels by orthogonal coordinates, and the probability that the Xn-Yn pixels are voids is C. This value corresponds to the degree of uniform dispersion of bubbles. In addition, the ratio A of the cross-sectional area of the void of any cross-section of any dot of the resistor to the total cross-sectional area and the total cross-sectional area of the cross-sectional area of the void of any cross-section of any other low antibody dot The ratio A / B with the ratio B occupied is D. This value is an index of the uniform dispersion of bubbles between the resistor dots.
また、表中の熱効率はO.D.＝1.0の時の比較例の入力
エネルギを１とした時の比率である。Further, the thermal efficiency in the table is a ratio when the input energy of the comparative example is 1 when OD = 1.0.
表の結果をはじめとする種類の実験結果から、抵抗体
ドット内の気泡直径、気泡率（空隙率）、気泡の均一分
散度Ｃ、さらには抵抗体ドット間の気泡の分散度Ｄが、
以下の範囲の時に本発明の効果が得られる。 From the results of various types of experiments including the results in the table, the bubble diameter in the resistor dots, the bubble ratio (void ratio), the uniform dispersion C of the bubbles, and the dispersion D of the bubbles between the resistor dots are
The effects of the present invention can be obtained within the following ranges.
（１） 最大気泡径＜電極間距離もしくは、抵抗体層の
厚さの1/5 （２） 気泡率＜0.5 （３） 0.3＜Ｃ＜0.7 （４） 0.3＜Ｄ＜0.7 なお本発明の具体的な実施例では抵抗体層中の気泡に
ついて述べたが、耐摩耗層中の気泡についても抵抗体層
と同じことが云える。すなわち耐摩耗性ガラス層の低気
泡量化もしくはその均一分散化により抵抗体層から感熱
紙への熱の伝達が均一に行われ印字品質が優れたものと
なる。(1) Maximum bubble diameter <distance between electrodes or 1/5 of thickness of resistor layer (2) Bubble ratio <0.5 (3) 0.3 <C <0.7 (4) 0.3 <D <0.7 Although the air bubbles in the resistor layer have been described in the specific examples, the same can be said for the bubbles in the wear resistant layer. That is, by reducing the amount of bubbles in the abrasion-resistant glass layer or by uniformly dispersing the bubbles, heat is uniformly transferred from the resistor layer to the thermal paper, resulting in excellent printing quality.
発明の効果 以上記載のように本発明のサーマルヘッドは抵抗体層
中の気泡の量が非常に少ないか、気泡が存在しても抵抗
体層中に均一に分散して存在している。このため、個々
のドット間での発熱が均一になり印字濃度ムラが非常に
少なくなる。EFFECTS OF THE INVENTION As described above, in the thermal head of the present invention, the amount of bubbles in the resistor layer is very small, or even if bubbles are present, they are evenly dispersed in the resistor layer. For this reason, the heat generation is uniform among the individual dots, and the print density unevenness is greatly reduced.
第１図は伝熱状態を示すサーマルヘッドの模式図、第２
図は抵抗体ドット間の気泡の分布を示す模式図、第３図
は印字ドットの正常な形および異常な形の例を示す図、
第４図は本発明の実施例で用いた抵抗ペーストの焼成温
度パターンを示す図、第５図は従来のサーマルヘッドの
構成図である。 １……発熱抵抗体層、２……耐摩耗層、３……感熱紙、
４……絶縁基板、５……電極、６……プラテンロール、
７……気泡、８……熱の流れ。FIG. 1 is a schematic view of a thermal head showing a heat transfer state,
The figure is a schematic diagram showing the distribution of bubbles between resistor dots, and Fig. 3 is a diagram showing examples of normal and abnormal shapes of print dots,
FIG. 4 is a diagram showing a firing temperature pattern of the resistance paste used in the examples of the present invention, and FIG. 5 is a configuration diagram of a conventional thermal head. 1 ... Heating resistor layer, 2 ... Wear resistant layer, 3 ... Thermal paper,
4 ... Insulating substrate, 5 ... Electrode, 6 ... Platen roll,
7 ... Bubbles, 8 ... Heat flow.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 渡辺 善博 大阪府門真市大字門真1006番地 松下電 器産業株式会社内 (72)発明者 竹内 康弘 大阪府門真市大字門真1006番地 松下電 器産業株式会社内 (56)参考文献 特開 昭62−50160（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yoshihiro Watanabe 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasuhiro Takeuchi 1006 Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-62-50160 (JP, A)
Claims (6)
の全断面積に占める比率が0.5以下であることを特徴と
するサーマルヘッド。1. A thermal head characterized in that the ratio of the cross-sectional area of the void portion of any cross section of the heating resistor to the total cross-sectional area is 0.5 or less.
ドット内及び抵抗体ドット間に均一に分散して存在する
ことを特徴とするサーマルヘッド。2. A thermal head characterized in that air bubbles existing in a heating resistor are uniformly dispersed in individual low antibody dots and between resistor dots.
る電極間距離もしくは発熱抵抗体の厚さの1/5より短い
ことを特徴とする請求項１または請求項２に記載のサー
マルヘッド。3. The thermal head according to claim 1, wherein the diameter of the bubbles in the heat generating resistor is shorter than 1/5 of the distance between the electrodes facing each other or the thickness of the heat generating resistor. .
部の断面積の全断面積に占める比率Ａと、他の任意の抵
抗体ドットの任意の断面の空隙部の断面積の全断面積に
占める比率Ｂとの比率A/Bが、0.3以上0.7以下であるこ
とを特徴とする請求項１または請求項２に記載のサーマ
ルヘッド。4. A ratio A of a sectional area of a void portion of an arbitrary cross section of an arbitrary dot of a resistor to a total sectional area and a total sectional area of a void part of an arbitrary cross section of another arbitrary resistor dot. The thermal head according to claim 1 or 2, wherein the ratio A / B with the ratio B in the cross-sectional area is 0.3 or more and 0.7 or less.
成を、徐昇温，徐冷却の焼成パターンで行うことを特徴
とする請求項１または請求項２に記載のサーマルヘッド
の製造法。5. The method of manufacturing a thermal head according to claim 1, wherein the resistor paste forming the heating resistor is fired in a firing pattern of gradual temperature increase and gradual cooling.
ダの分解温度または、気化温度まで５℃/min以下の昇温
速度で行われることを特徴とする請求項５に記載のサー
マルヘッドの製造法。6. The method for producing a thermal head according to claim 5, wherein the firing is performed at least at a decomposition temperature of the organic binder in the paste or a vaporization temperature at a heating rate of 5 ° C./min or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4622888A JP2563444B2 (en) | 1988-02-29 | 1988-02-29 | Thermal head and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4622888A JP2563444B2 (en) | 1988-02-29 | 1988-02-29 | Thermal head and manufacturing method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01218854A JPH01218854A (en) | 1989-09-01 |
| JP2563444B2 true JP2563444B2 (en) | 1996-12-11 |
Family
ID=12741255
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4622888A Expired - Fee Related JP2563444B2 (en) | 1988-02-29 | 1988-02-29 | Thermal head and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2563444B2 (en) |
-
1988
- 1988-02-29 JP JP4622888A patent/JP2563444B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01218854A (en) | 1989-09-01 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |