DE2310641A1 - PRINT HEAD - Google Patents

PRINT HEAD

Info

Publication number
DE2310641A1
DE2310641A1 DE19732310641 DE2310641A DE2310641A1 DE 2310641 A1 DE2310641 A1 DE 2310641A1 DE 19732310641 DE19732310641 DE 19732310641 DE 2310641 A DE2310641 A DE 2310641A DE 2310641 A1 DE2310641 A1 DE 2310641A1
Authority
DE
Germany
Prior art keywords
print head
head according
resistance elements
valve metal
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
Application number
DE19732310641
Other languages
German (de)
Inventor
Herbert Dr Knauer
Bernhard Koehne
Guenter Dr Rer Nat Krueger
Klaus-Dieter Trachmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Robert Bosch GmbH
Original Assignee
Robert Bosch GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Priority to DE19732310641 priority Critical patent/DE2310641A1/en
Priority to FR7343604A priority patent/FR2220139A5/fr
Priority to JP49023713A priority patent/JPS5025239A/ja
Publication of DE2310641A1 publication Critical patent/DE2310641A1/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/33505Constructional details
    • B41J2/33515Heater layers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/33505Constructional details
    • B41J2/33525Passivation layers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/33505Constructional details
    • B41J2/3353Protective layers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/33505Constructional details
    • B41J2/33535Substrates
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/3355Structure of thermal heads characterised by materials
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B41PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41JTYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
    • B41J2/00Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
    • B41J2/315Typewriters 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
    • B41J2/32Typewriters 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
    • B41J2/335Structure of thermal heads
    • B41J2/33555Structure of thermal heads characterised by type
    • B41J2/3357Surface type resistors

Landscapes

  • Semiconductor Memories (AREA)
  • Electronic Switches (AREA)
  • Facsimile Heads (AREA)

Description

7
R.
7th
R.

12.2.1973 Fb/DrFebruary 12, 1973 Fb / Dr

Anlage zurAttachment to

Patent- undPatent and

GebrauchsmusterhilfsanmeldungUtility model registration

ROBERT BOSCH GMBH, 7 Stuttgart 1ROBERT BOSCH GMBH, 7 Stuttgart 1

KG Dr.-Ιηκ. H. Knauer & Co, GmbH, 1 Berlin 37KG Dr.-Ιηκ. H. Knauer & Co, GmbH, 1 Berlin 37

DruckkopfPrinthead

Die Erfindung betrifft einen Druckkopf zur Aufzeichnung von Informationen auf einen thermoempfindlichen Aufzeichnungsträger mit einem elektrisch beheizbaren Schreiborgan.The invention relates to a print head for recording information on a thermosensitive recording medium with an electrically heated writing element.

Digital angezeigte Meßwerte sollen häufig in einem Registriervorgang ausgedruckt und gespeichert werden. Eine Möglichkeit dazu bietet das sogenannte Thermodruck-Verfahren, bei welchem auf einem wärmeempfindlichen Papier eine Farbänderung an allen den Stellen erzeugt wird, an denen V/ärme übertragen wird.Digitally displayed measured values are often to be included in a registration process can be printed out and saved. One possibility for this is the so-called thermal printing process, in which a color change is produced on a heat-sensitive paper at all the places where V / poor is transmitted.

Es ist bereits ein Druckkopf zur Aufzeichnung von Informationen auf einen thermoempfindlichen Aufzeichnungsträger bekannt, bei welchem das elektrisch beheizbare Schreiborgan aus einem System von Halbleiterelementen besteht, die auf einem einzigen Halbleiterchip angeordnet und je einzelnIt is already a print head for recording information on a thermosensitive recording medium known, in which the electrically heatable writing element consists of a system of semiconductor elements on arranged on a single semiconductor chip and each individually

409838/0423409838/0423

— p _- p _

O - O -

durch ein System von Steuereinheiten ansteuerbar sind, die ebenfalls Bestandteil des Halbleiterchips sind. Die Herstellung dieses bekannten Druckkopfes ist aber sehr kompliziert und der Druckkopf deshalb teuer.can be controlled by a system of control units, which are also part of the semiconductor chip. The production however, this known print head is very complicated and the print head is therefore expensive.

Der Erfindung liegt die Aufgabe zugrunde, einen in der Herstellung einfacheren und billigeren Druckkopf der eingangs genannten Art zu entwickeln.The invention is based on the object of producing a printhead which is simpler to manufacture and cheaper called type to develop.

Erfindungsgemäß ist diese Aufgabe dadurch gelöst, daß das Schreiborgan aus einem System von Widerstandselementen und Leiterbahnen gebildet ist, die auf ein elektrisch nichtleitendes Substrat aufgebracht sind. In weiterer Ausgestaltung der Erfindung wird vorgeschlagen, die Widerstandselemente und die Leiterbahnen als Dünnschichtelemente oder als Dickschichtelemente auszubilden. Es kann auch eine Kombination beider Technologien verwendet werden.According to the invention this object is achieved in that the writing element is formed from a system of resistance elements and conductor tracks, which are connected to an electrically non-conductive substrate are applied. In a further embodiment of the invention, it is proposed that the resistance elements and to form the conductor tracks as thin-film elements or as thick-film elements. It can also be a Combination of both technologies can be used.

Anhand der Zeichnung wird die Erfindung näher erläutert. Es zeigen:The invention is explained in more detail with the aid of the drawing. Show it:

Fig. 1 eine Draufsicht auf ein Schreiborgan gemäß derFig. 1 is a plan view of a writing member according to the

Erfindung;
Fig. 2 einen Schnitt nach der Linie II-II der Fig. 1, in welchem die Dicke der Widerstandselemente und Leiterbahnen in stark vergrößertem Maßstab dargestellt ist.
Invention;
FIG. 2 shows a section along the line II-II of FIG. 1, in which the thickness of the resistance elements and conductor tracks is shown on a greatly enlarged scale.

In den Figuren 1 und 2 ist mit 1 das das Schreiborgan tragende elektrisch nichtleitende Substrat bezeichnet. Auf das Substrat 1 ist eine die Grundgeometrie des Schaltungsnetzwerks enthaltende Schicht 2 aus Ventilmetall von 1000 A Dicke aufgebracht. Unter Ventilmetall versteht man ein Metall, das ein einen Gleichstrom, sperrendes Oxid bildet. Vorzugsweise ist als Ventilmetall Tantal vorgesehen. Statt dessen können aber auch die Metalle Niob, Aluminium, Zirkonium und Hafnium verwendet werden. Die VentilmetallschichtIn Figures 1 and 2, 1 is the writing organ bearing electrically non-conductive substrate. On the substrate 1 is the basic geometry of the circuit network containing layer 2 of valve metal of 1000 Å thick. Understood by valve metal a metal that is a direct current blocking oxide forms. Tantalum is preferably provided as the valve metal. Instead, however, the metals niobium, aluminum, Zirconium and hafnium can be used. The valve metal layer

409838/0423 - 3 -409838/0423 - 3 -

2 trägt an denjenigen Oberflächenbereichen, die die schreibenden Teile 2' des Schreiborgans bilden, eine Oxidschicht 3, die dadurch hergestellt ist, daß die Ventilmetallschicht 2 an diesen Stellen teilweise anodisch oxidiert ist. Die Ventilmetallschicht 2 trägt .an denjenigen Oberflächenbereichen, die nicht zu den schreibenden Teilen 2' gehören, eine aus drei Schichten 4, 5» 6 bestehende Metallisierung. Die unterste Schicht k und die oberste Schicht 6 digser Metallisierung sind jeweils Kupferschichten von 2000 A Dicke. Die zwischen diesen beiden Kupferschichten 1I und 6 verlaufende Zwischenschicht 5 besteht aus einem als Diffusionssperre wirkenden Metall, beispielsweise aus Eisen, Nickel oder Kobalt. Die Dicke dieser Schicht 5 beträgt 1IOOO A. Die aus den Schichten ^, 5, 6 bestehende Metallisierung ist an allen denjenigen Stellen auf die Ventilmetallschicht 2 aufgebracht, die für Leiterbahnen und für Anschlußkontakte vorgesehen sind.2 has an oxide layer 3 on those surface areas which form the writing parts 2 'of the writing element, which oxide layer 3 is produced in that the valve metal layer 2 is partially anodized at these points. The valve metal layer 2 has a metallization consisting of three layers 4, 5, 6 on those surface areas that do not belong to the writing parts 2 '. The bottom layer k and the top layer 6 digser metallization are each copper layers with a thickness of 2000 Å. Between these two copper layers I 1 and 6 extending intermediate layer 5 consists of an acting as a diffusion barrier metal, such as iron, nickel or cobalt. The thickness of this layer 5 is 1 IOOO A. consisting of the layers ^, 5, 6 metallization is deposited on all those points on the valve metal layer 2, which are provided for conductors and for connection contacts.

Die nicht mit den Schichten 1J, 5 und 6 behafteten, oxidierten Teile 2' der Ventilmetallschicht 2 stellen ein System von Widerstandselementen dar, das sich bei Stromdurchgang erwärmt und die schreibenden Teile des Schreiborgans bildet. Die zwischen den einzelnen Widerstandselementen 21 befindlichen, aus den Schichten 2, 1I, 5* 6 bestehenden Leiterbahnen sind dagegen so niederohmig, daß bei Stromdurchgang ihre Erwärmung so gering ist, daß der thermoenpfindliche Aufzeichnungsträger hierauf nicht anspricht. Es entsteht also beim Druckvorgang jeweils ein Abbild derjenigen Widerstandselemente 2' auf den thermoempfindlichen Aufzeichnungsträger, die im Augenblick mit Strom durchflossen sind. Die Schreibelemente 21 des Schreiborgans und die Leiterbahnen sind hierzu so ausgebildet und angeordnet, daß jeweils verschiedene Teilbereiche des Schreiborgans, die mehrere Widerstandselemente enthalten,unabhängig voneinander ein- bzw. ausgeschaltet v/erden können. Dabei ist das Muster insgesamt so ausgebildet, daß mit ihm alle arabischen Zahlen geschriebenThe non-lossy layers 1 J, 5 and 6, oxidized portions 2 'of the valve metal layer 2 illustrate a system of resistive elements which heat up when current passes through and forms the written parts of the writing member. The conductor tracks located between the individual resistance elements 2 1 and consisting of the layers 2, 1 I, 5 * 6, on the other hand, are so low-resistance that when current passes through them, their heating is so low that the thermo-sensitive recording medium does not respond to them. During the printing process, an image of those resistance elements 2 'is created on the thermosensitive recording medium through which current is flowing at the moment. For this purpose, the writing elements 2 1 of the writing element and the conductor tracks are designed and arranged in such a way that different partial areas of the writing element, which contain several resistance elements, can be switched on or off independently of one another. The pattern is designed in such a way that all Arabic numbers are written with it

409838/0423409838/0423

_ I4 __ I 4 _

werden können. can be.

Selbstverständlich lassen sich mit Hilfe der Dünnschichttechnik beliebig ausgebildete Muster herstellen, so daß die Erfindung nicht auf das in der Zeichnung dargestellte Ausführungsbeispiel beschränkt ist.Of course, any pattern can be produced with the aid of thin-film technology, so that the invention is not limited to the embodiment shown in the drawing.

Ferner kann die aus den drei Schichten 4,5 und 6 bestehende Metallisierung durch eine einzige Metallschicht, beispielsweise aus Kupfer, ersetzt werden. Anstelle dieser Kupferschicht kann mit besonderem Vorteil auch eine Schicht aus einem an Luft nicht oxidierbaren Metall, beispielsweise aus Silber oder Gold oder aus einem Metall der achten Nebengruppe des periodischen Systems, verwendet werden.Furthermore, it can consist of the three layers 4, 5 and 6 Metallization can be replaced by a single metal layer, for example made of copper. Instead of this The copper layer can with particular advantage also be a layer made of a metal which cannot be oxidized in air, for example made of silver or gold or of a metal of the eighth subgroup of the periodic system.

Das Schreiborgan kann auch aus einer auf das Substrat 1 aufgebrachten Dickschichtschaltung bestehen.The writing element can also consist of a thick-film circuit applied to the substrate 1.

409838/0423409838/0423

Claims (8)

AnsprücheExpectations ruckkopf zur Aufzeichnung von Informationen auf einen thermoempfindlichen Aufzeichnungsträger mit einem elektrisch beheizbaren Schreiborgan, dadurch gekennzeichnet, daß das Schreiborgan aus einem System von Widerstandselementen (21) und Leiterbahnen gebildet ist, die auf ein elektrisch nichtleitendes Substrat (1) aufgebracht sind.Back head for recording information on a thermosensitive recording medium with an electrically heatable writing element, characterized in that the writing element is formed from a system of resistance elements (2 1 ) and conductor tracks which are applied to an electrically non-conductive substrate (1). 2. Druckkopf nach Anspruch 1, dadurch gekennzeichnet, daß die Widerstandselemente (2') und die Leiterbahnen als Dünnschichtelemente ausgebildet sind.2. Print head according to claim 1, characterized in that the resistance elements (2 ') and the conductor tracks as Thin-film elements are formed. 3· Druckkopf nach Anspruch 2, dadurch gekennzeichnet, daß die Widerstandselemente (21) durch Teile einer Ventilmetallschicht (2) gebildet werden.3. Print head according to claim 2, characterized in that the resistance elements (2 1 ) are formed by parts of a valve metal layer (2). 1I. Druckkopf nach Anspruch 3> dadurch gekennzeichnet, daß als Ventilmetall Tantal oder Niob oder Aluminium oder Zirkonium oder Hafnium verwendet ist. 1 I. Print head according to claim 3> characterized in that the valve metal used is tantalum or niobium or aluminum or zirconium or hafnium. 5· Druckkopf nach Anspruch 3, dadurch gekennzeichnet, daß die Leiterbahnen aus der Ventilmetallschicht (2) und einer im Bereich außerhalb der Widerstandselemente (21) auf die Ventilmetallschicht (2) aufgebrachten Metallisierung bestehen.5 · print head according to claim 3, characterized in that the conductor tracks of the valve metal layer (2) and an applied in the area outside of the resistance elements (2 1) to the valve metal layer (2) consist metallization. 6. Druckkopf nach Anspruch 5, dadurch gekennzeichnet, daß die Metallisierung aus Kupfer oder Silber oder Gold oder aus einem Metall der achten Nebengruppe des periodischen Systems6. Print head according to claim 5, characterized in that the metallization is made of copper or silver or gold or from a metal of the eighth subgroup of the periodic system besteht. 409838/0423consists. 409838/0423 7. Druckkopf nach Anspruch 5, dadurch gekennzeichnet, daß die Metallisierung aus einer ersten (1I) und zweiten (6) Kupferschicht und einer zwischen diesen beiden Kupferschichten (1,6) angeordneten Zwischenschicht (5) aus Eisen besteht.7. Print head according to claim 5, characterized in that the metallization consists of a first ( 1 I) and second (6) copper layer and an intermediate layer (5) made of iron between these two copper layers (1,6). 8. Druckkopf nach Anspruch 2, dadurch gekennzeichnt, daß auf die Widerstandselemente (2·) eine Oxidschicht (3) aufgebracht ist. 8. Print head according to claim 2, characterized in that an oxide layer (3) is applied to the resistance elements (2 ·) . 409838/0A23409838 / 0A23 LeerseiteBlank page
DE19732310641 1973-03-01 1973-03-01 PRINT HEAD Pending DE2310641A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
DE19732310641 DE2310641A1 (en) 1973-03-01 1973-03-01 PRINT HEAD
FR7343604A FR2220139A5 (en) 1973-03-01 1973-12-06
JP49023713A JPS5025239A (en) 1973-03-01 1974-02-28

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19732310641 DE2310641A1 (en) 1973-03-01 1973-03-01 PRINT HEAD

Publications (1)

Publication Number Publication Date
DE2310641A1 true DE2310641A1 (en) 1974-09-19

Family

ID=5873700

Family Applications (1)

Application Number Title Priority Date Filing Date
DE19732310641 Pending DE2310641A1 (en) 1973-03-01 1973-03-01 PRINT HEAD

Country Status (3)

Country Link
JP (1) JPS5025239A (en)
DE (1) DE2310641A1 (en)
FR (1) FR2220139A5 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0029985A1 (en) * 1979-11-28 1981-06-10 Kabushiki Kaisha Toshiba Printed wiring board for recording or displaying information

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS54126049A (en) * 1978-03-23 1979-09-29 Matsushita Electric Ind Co Ltd Thin film type thermal head and production thereof
FR2485796A1 (en) * 1980-06-24 1981-12-31 Thomson Csf HEATING ELECTRIC RESISTANCE AND THERMAL PRINTER HEAD COMPRISING SUCH HEATING RESISTORS

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4825540A (en) * 1971-08-02 1973-04-03

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0029985A1 (en) * 1979-11-28 1981-06-10 Kabushiki Kaisha Toshiba Printed wiring board for recording or displaying information

Also Published As

Publication number Publication date
FR2220139A5 (en) 1974-09-27
JPS5025239A (en) 1975-03-17

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