EP0044756A2 - Heizwiderstand und thermischer Druckkopf, der solche Heizwiderstände verwendet - Google Patents

Heizwiderstand und thermischer Druckkopf, der solche Heizwiderstände verwendet Download PDF

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Publication number
EP0044756A2
EP0044756A2 EP81400923A EP81400923A EP0044756A2 EP 0044756 A2 EP0044756 A2 EP 0044756A2 EP 81400923 A EP81400923 A EP 81400923A EP 81400923 A EP81400923 A EP 81400923A EP 0044756 A2 EP0044756 A2 EP 0044756A2
Authority
EP
European Patent Office
Prior art keywords
layer
resistivity
temperature
resistors
resistance
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.)
Granted
Application number
EP81400923A
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English (en)
French (fr)
Other versions
EP0044756A3 (en
EP0044756B1 (de
Inventor
Christian Val
Didier Pribat
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.)
Thales SA
Original Assignee
Thomson CSF SA
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 Thomson CSF SA filed Critical Thomson CSF SA
Publication of EP0044756A2 publication Critical patent/EP0044756A2/de
Publication of EP0044756A3 publication Critical patent/EP0044756A3/fr
Application granted granted Critical
Publication of EP0044756B1 publication Critical patent/EP0044756B1/de
Expired legal-status Critical Current

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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
    • B41J2/33505—Constructional details
    • B41J2/33515—Heater layers
    • 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
    • B41J2/33505—Constructional details
    • B41J2/33535—Substrates
    • 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
    • B41J2/3355—Structure of thermal heads characterised by materials
    • 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
    • B41J2/33555—Structure of thermal heads characterised by type
    • B41J2/3357—Surface type resistors

Definitions

  • the invention relates to a structure of heating elements, of the type of resistors mounted in series in the form of rectilinear plates, more particularly intended for the production of thermal printer heads. It also relates to the circuit for controlling thermal printer heads, which is simplified by the adoption of resistors according to the invention.
  • Thermal printers are peripheral devices of computer or telecommunications systems, in which the printing of a line of text is obtained by means of a strip of heating resistors: the heat given off by an elementary resistance chemically modifies the paper on which registration is done.
  • Printing a line of characters using a thermal printer head is obtained by repeating several lines of dots at the rate of 8 points per millimeter.
  • a thermal printer head for a standard paper size of 21 cm wide, has 1728 resistors, deposited on a glass or ceramic plate. Each resistor has dimensions of the order of 250 microns in width and the resistors are spaced from each other by 250 microns.
  • Thermal printer heads pose two problems: that of controlling a specific resistance and that of heat dissipation.
  • Each programmed unit resistor is controlled by a circuit comprising, among other things, two transistors and a diode.
  • the diodes connected in series with the non-programmed resistors limit the potential across its terminals and prevent them from heating up.
  • a thermal printer head therefore requires a circuit comprising as many diodes as there are heating resistors or at best, according to the scheme adopted, a number of diodes equal to half the number of heating resistors, the number of diodes remaining important since it is therefore at least 863 diodes, for 1728 points.
  • the characteristics of the resistors according to the invention which comprise at least one layer operating as a non-linear resistance with a negative temperature coefficient, with a tilting point, make it possible to eliminate the diodes in the supply circuit of the heating resistors.
  • the heating resistors which are small, have a low calorific capacity, and the heat released is partly absorbed by the substrate whose calorific capacity is much greater.
  • an array of in-line heating resistors is produced on a substrate which is a glass or ceramic plate, the length of which is equal to the width of the printing paper, and the thickness of which is of the order of a few millimeters to ensure the rigidity and non-fragility of the thermal printer module. It is therefore an improvement to the thermal heads provided by the invention according to which the heating resistors comprise a warmer outer layer which dissipates the heat preferentially towards the paper rather than towards the substrate wafer.
  • the invention consists of an electrical heating resistor, deposited on an insulating substrate of glass or ceramic, whose heat capacity is much higher than that of the heating resistor, characterized in that it comprises at least a first layer of a material of relatively constant resistivity as a function of temperature, deposited on the substrate and at least a second surface layer of a material of resistivity variable in a non-linear manner with temperature, with a negative temperature coefficient, this second layer being deposited on the first layer.
  • FIG. 1 represents the electrical diagram of the current supply of the heating resistors in a thermal head. The explanation of its operation will better show the advantages of the invention.
  • the heating resistors numbered from 1 to 5 are connected in series and are supplied by group, from several power transistors, two of which have been represented in 6 and 7.
  • the power transistor 6 supplies the resistors 1, 4 and 5, while the power transistor 7 supplies the resistors 2 and 3.
  • the groups are interdigitated and the choice or the programming of a resistance which must heat is determined by a transistor such as 8, 9 or 10, the base of which is controlled by a shift register.
  • Resistor 1 is controlled by transistor 6 and transistor 8
  • resistance 2 is controlled by transistor 7 and transistor 8
  • resistor 3 is controlled by transistor 7 and transistor 9 ... and so on.
  • diodes 12, 13 and 14 are diodes 12, 13 and 14 in the figure 1.
  • the heating resistors according to the known art have relatively low values and the simple leakage current through an unprogrammed transistor is sufficient to heat an unprogrammed resistor: the presence of the diodes limits the potential at the terminals of the resistors not programmed.
  • FIG. 1 Although the diagram of FIG. 1 is only very partial compared to the complete diagram of a thermal printer head, it appears that the electrical assembly requires the assembly, inter alia, of a large number of diodes which are implanted on relatively complex circuits by the large number of conductors they require as well as the large number of welds, which is a drawback for the industrial assembly of a thermal printer head.
  • the replacement of conventional heating resistors by heating resistors according to the invention has the advantage of eliminating the diodes, because of the high value that the heating resistors have when cold, a value which decreases very quickly as soon as the surface layer which is consisting of a resistance with a negative temperature coefficient has reached and exceeded its tipping point.
  • Figure 2 shows the sectional view of a heating resistor according to the known art. This figure provides a better understanding of the problems of heat dissipation.
  • each heating resistor 16 deposited by screen printing, by vacuum evaporation or by any other similar process has a thickness which is best counted in tenths of a millimeter.
  • the resistors according to the known art are deposited by means of one or more passages by accumulation of layers which are all made from the same base material, and therefore all the layers have the same characteristics of resistivity and temperature coefficient.
  • Figure 3 shows a sectional view of a resistor according to the invention.
  • first resistance layer 18 which will be conventionally called fixed as opposed to a second layer 19 of non-linearly variable resistance with a negative temperature coefficient.
  • first layer 18 being a fixed resistance
  • second layer 19 being a variable CTN resistance mounted in parallel with the fixed resistance R.
  • the set of two resistors 18 and 19 which constitute the resistance according to the invention has a high value.
  • the resistor R heats the variable resistor CTN until it reaches its tipping point: from this temperature the CTN considerably decreases in resistance, it becomes conductive and the heat released is largely released by the external surface of the heating resistor, that is to say in contact with the sheet of paper.
  • the first resistance layer 18 can be of the linear type, that is to say that its value practically does not vary with temperature, in comparison with the variation of the CTN. But it is an improvement to the invention to use as a first layer a resistance with positive temperature coefficient PTC: this behaves like a linear resistance up to its tilting temperature, temperature at which its resistance increases considerably and abruptly. However, this solution requires a fairly good choice of materials from the CTP and the CTN, so that the two switching temperatures are substantially overlap, that is to say that the CTN becomes "conductive" when the CTP ceases to be.
  • the invention provides that the layer 19 is deposited on the layer 18 without exceed it in such a way that the layer 19 does not have contact with the substrate 15.
  • FIG. 4 represents the resistance characteristics as a function of the temperature of the resistors with a non-linear negative temperature coefficient.
  • the heating resistors according to the invention therefore have the advantage of having a high value at ordinary temperature and then, when they have been programmed and the underlying resistance layer has heated the variable resistance layer, they do not have more than a low resistance value, which allows on the one hand to remove the diodes in the supply circuit since the other resistors, not programmed, have high values, and on the other hand to dissipate the heat mainly towards paper.
  • An improvement to the invention consists in programming in perma nence a low current through all the heating resistors so as to maintain them at a constant temperature outside of any programming which is slightly lower than the switching temperature.
  • FIG. 5 represents an improvement made to the structure of the heating resistors according to the invention.
  • the description of the invention, in FIG. 3, was based on the simplest case where a layer with variable resistivity 19 is deposited on a single layer with constant resistivity 18. However, it is an improvement to achieve a variable resistivity layer 19 on a plurality of constant resistivity layers, two of which have been represented at 18 and at 20 in FIG. 5.
  • variable resistivity layer 19 on a support composed of a plurality of layers from 1 to n, the resistivity of each layer decreasing from layer 1 to layer n.
  • each layer is deposited in such a way that only the first layer touches the substrate 15 of the thermal printer head, so as to focus the heat given off in each layer, heat which is greater in one layer than in the previous one, towards the external surface of the thermal resistance, which makes it the external surface which is the warmest and which modifies the paper used in the thermal printer.
  • the invention has been explained on the basis of the case of a resistance strip for a thermal printer head. However, it also applies to all cases where a large number of resistors must be programmed to control a large number of elements, such as display panels or any other electronic device in which a large number of times are repeated the same control operations via resistors. In addition, the improvements which can be made, improvements, fall within the field of the invention. inherent in a person skilled in the art who knows well the field of resistors with a negative temperature coefficient.

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EP81400923A 1980-06-24 1981-06-11 Heizwiderstand und thermischer Druckkopf, der solche Heizwiderstände verwendet Expired EP0044756B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8013967A FR2485796A1 (fr) 1980-06-24 1980-06-24 Resistance electrique chauffante et tete d'imprimante thermique comportant de telles resistances chauffantes
FR8013967 1980-06-24

Publications (3)

Publication Number Publication Date
EP0044756A2 true EP0044756A2 (de) 1982-01-27
EP0044756A3 EP0044756A3 (en) 1982-02-10
EP0044756B1 EP0044756B1 (de) 1984-08-29

Family

ID=9243445

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81400923A Expired EP0044756B1 (de) 1980-06-24 1981-06-11 Heizwiderstand und thermischer Druckkopf, der solche Heizwiderstände verwendet

Country Status (4)

Country Link
US (1) US4413170A (de)
EP (1) EP0044756B1 (de)
DE (1) DE3165766D1 (de)
FR (1) FR2485796A1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0142964A2 (de) * 1983-11-12 1985-05-29 Victor Company Of Japan, Limited Vorrichtung und Verfahren zum Thermodrucken mit Farbübertragung
EP0218372A1 (de) * 1985-09-04 1987-04-15 British Aerospace Public Limited Company Vorrichtung zur Herstellung eines thermischen Bildes

Families Citing this family (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4484823A (en) * 1981-01-17 1984-11-27 Fag Kugelfischer Georg Schafer & Co. Method of determining the boiling point of a liquid
JPS5949985A (ja) * 1982-09-14 1984-03-22 Toshiba Corp 感熱印字方式
JPS60184858A (ja) * 1984-03-02 1985-09-20 Hitachi Ltd サ−マルヘツド
US4528539A (en) * 1984-06-28 1985-07-09 Eaton Corporation Reduced-size thermal overload relay
JPS6186269A (ja) * 1984-10-04 1986-05-01 Tdk Corp サ−マルヘツド
FR2591801B1 (fr) * 1985-12-17 1988-10-14 Inf Milit Spatiale Aeronaut Boitier d'encapsulation d'un circuit electronique
US4947189A (en) * 1989-05-12 1990-08-07 Eastman Kodak Company Bubble jet print head having improved resistive heater and electrode construction
FR2688629A1 (fr) * 1992-03-10 1993-09-17 Thomson Csf Procede et dispositif d'encapsulation en trois dimensions de pastilles semi-conductrices.
JPH05275161A (ja) * 1992-03-26 1993-10-22 Rohm Co Ltd ライン型加熱体
US5408070A (en) * 1992-11-09 1995-04-18 American Roller Company Ceramic heater roller with thermal regulating layer
FR2709020B1 (fr) * 1993-08-13 1995-09-08 Thomson Csf Procédé d'interconnexion de pastilles semi-conductrices en trois dimensions, et composant en résultant.
DE4328791C2 (de) * 1993-08-26 1997-07-17 Siemens Matsushita Components Hybrid-Thermistortemperaturfühler
BE1007868A3 (nl) * 1993-12-10 1995-11-07 Koninkl Philips Electronics Nv Elektrische weerstand.
FR2719967B1 (fr) * 1994-05-10 1996-06-07 Thomson Csf Interconnexion en trois dimensions de boîtiers de composants électroniques utilisant des circuits imprimés.
FR2780808B1 (fr) 1998-07-03 2001-08-10 Thomson Csf Dispositif a emission de champ et procedes de fabrication
FR2802706B1 (fr) * 1999-12-15 2002-03-01 3D Plus Sa Procede et dispositif d'interconnexion en trois dimensions de composants electroniques
FR2875672B1 (fr) * 2004-09-21 2007-05-11 3D Plus Sa Sa Dispositif electronique avec repartiteur de chaleur integre
FR2894070B1 (fr) * 2005-11-30 2008-04-11 3D Plus Sa Sa Module electronique 3d
FR2895568B1 (fr) * 2005-12-23 2008-02-08 3D Plus Sa Sa Procede de fabrication collective de modules electroniques 3d
FR2905198B1 (fr) * 2006-08-22 2008-10-17 3D Plus Sa Sa Procede de fabrication collective de modules electroniques 3d
FR2923081B1 (fr) * 2007-10-26 2009-12-11 3D Plus Procede d'interconnexion verticale de modules electroniques 3d par des vias.
FR2940521B1 (fr) 2008-12-19 2011-11-11 3D Plus Procede de fabrication collective de modules electroniques pour montage en surface
FR2943176B1 (fr) 2009-03-10 2011-08-05 3D Plus Procede de positionnement des puces lors de la fabrication d'une plaque reconstituee
US8143559B2 (en) * 2009-09-01 2012-03-27 Advance Thermo Control, Ltd. Heating pad with temperature control and safety protection device
JP6930696B2 (ja) * 2016-10-14 2021-09-01 ローム株式会社 サーマルプリントヘッド

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2220139A5 (de) * 1973-03-01 1974-09-27 Bosch Gmbh Robert
FR2311410A1 (fr) * 1975-05-13 1976-12-10 Thomson Csf Circuit de commutation integre, matrice de commutation et circuits logiques utilisant ledit circuit
US4213030A (en) * 1977-07-21 1980-07-15 Kyoto Ceramic Kabushiki Kaisha Silicon-semiconductor-type thermal head

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2915724A (en) * 1957-06-06 1959-12-01 Minnesota Mining & Mfg Electrical device
US3973106A (en) * 1974-11-15 1976-08-03 Hewlett-Packard Company Thin film thermal print head
US4246468A (en) * 1978-01-30 1981-01-20 Raychem Corporation Electrical devices containing PTC elements
US4206541A (en) * 1978-06-26 1980-06-10 Extel Corporation Method of manufacturing thin film thermal print heads

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2220139A5 (de) * 1973-03-01 1974-09-27 Bosch Gmbh Robert
FR2311410A1 (fr) * 1975-05-13 1976-12-10 Thomson Csf Circuit de commutation integre, matrice de commutation et circuits logiques utilisant ledit circuit
US4213030A (en) * 1977-07-21 1980-07-15 Kyoto Ceramic Kabushiki Kaisha Silicon-semiconductor-type thermal head

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0142964A2 (de) * 1983-11-12 1985-05-29 Victor Company Of Japan, Limited Vorrichtung und Verfahren zum Thermodrucken mit Farbübertragung
EP0142964A3 (en) * 1983-11-12 1986-06-18 Victor Company Of Japan, Limited Apparatus and method for thermal ink transfer printing
EP0218372A1 (de) * 1985-09-04 1987-04-15 British Aerospace Public Limited Company Vorrichtung zur Herstellung eines thermischen Bildes
US4769527A (en) * 1985-09-04 1988-09-06 British Aerospace Plc Thermal image generating device

Also Published As

Publication number Publication date
FR2485796B1 (de) 1983-07-22
US4413170A (en) 1983-11-01
EP0044756A3 (en) 1982-02-10
FR2485796A1 (fr) 1981-12-31
DE3165766D1 (en) 1984-10-04
EP0044756B1 (de) 1984-08-29

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