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US3683361A - Process for the manufacture of flat heating conductors and flat heating conductors obtained by this process - Google Patents

Process for the manufacture of flat heating conductors and flat heating conductors obtained by this process Download PDF

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Publication number
US3683361A
US3683361A US116488A US3683361DA US3683361A US 3683361 A US3683361 A US 3683361A US 116488 A US116488 A US 116488A US 3683361D A US3683361D A US 3683361DA US 3683361 A US3683361 A US 3683361A
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US
United States
Prior art keywords
dispersion
carbon black
weight
conductors
electrical 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.)
Expired - Lifetime
Application number
US116488A
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English (en)
Inventor
Manfred Salzwedel
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.)
Hoechst AG
Original Assignee
Hoechst AG
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 Hoechst AG filed Critical Hoechst AG
Application granted granted Critical
Publication of US3683361A publication Critical patent/US3683361A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
    • H05B3/12—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material
    • H05B3/14—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material the material being non-metallic
    • H05B3/146—Conductive polymers, e.g. polyethylene, thermoplastics
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D13/00—Electric heating systems
    • F24D13/02—Electric heating systems solely using resistance heating, e.g. underfloor heating
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49082—Resistor making
    • Y10T29/49083—Heater type

Definitions

  • the present invention relates to a process for the manufacture of flat heating conductors and flat heating conductors obtained by this process.
  • fiat heating conductors comprising a fabric or a fleece of textile fibers or glass fibers, on to which carbon has been applied in the form of carbon black or graphite by means of a plastics dispersion or a varnish-like binder.
  • the electrical supply leads are clamped in the form of strips to the edge of the support.
  • the relatively high contact resistance which produces local overheating, is disadvantageous as well as the fact that the bond strength of the conductive carbon layer decreases upon use.
  • the heating conductors cannot readily be adapted to any object to be heated, and the heat transfer occasionally leaves something to be desired.
  • flat heating conductors also known as electrical resistance heating elements
  • the process according to the invention consists in embedding at least two metallic conductors in a layer of a film-forming plastics dispersion which has been filled with carbon black, whereupon the dispersion is dried.
  • a heating conductor is obtained with any type of a carbon black. It was found, however, that for the purpose of the present invention it is most advantageo'us to use a carbon black which has been obtained by thermal splitting of acetylene. Other types of carbon black when added to the dispersion in the same amounts impart to the heating conductors resistances which are appreciably higher.
  • fiat heating conductors according to the invention When the fiat heating conductors according to the invention are applied to a surface they need no special reinforcement.
  • short textile fibers for example, 3 mm to 5 mm long polyesteror polyamide fibers, to the plastics dispersion filled with carbon black.
  • flat heating conductors can be produced directly on the objects to be heated, for example in the form of coatings.
  • the flat heating conductors may also simultaneously serve as floor heaters.
  • the flat heating conductors may on the surface be provided with a coat of unpigmented dispersions or with a coat of dispersions containing colored pigments (but in a manner such that the dispersions are non-conductive) and are thus electrically insulated.
  • the quadratic resistance of the flat heating conductors of the invention depends on different factors. It increases as the sheet thickness decreases and decreases as the content of carbon black increases. On the other hand, it is almost independent of the temperature, and I cally to the current flow, the resistance increases but regains its original value after short heating to about C.
  • FIG. 1 is a view in perspective of a supported heating conductor
  • FIG. 2 is a view in cross-section through a self-supporting heating conductor
  • FIG. 3 is a flow diagram of one method of forming the heating conductors of the present invention.
  • a conductor is illustrated as mounted on a suitable support 1, such as a wall panel, the conductor 2 being provided with a plurality of metallic conductors 3 covered with a cover layer 4 such as wallpaper.
  • the self-supporting heating conductor shown in FIG. 2 consists essentially of a plastic dispersion 2' containing a conductive material such as carbon black and having embedded therein a plurality of strips of metallic conductors 3', e.g., in the form of wire mesh.
  • the mass was filled into a flat polyethylene mold so as to form a 1 mm thick layer.
  • Two strips of a copper cloth (200 meshes) were inserted into this layer at a distance of 50 mm in a parallel direction to one another whereupon the mold was filled up with the mass until the layer had a thickness of 2 mm. Then the mass was allowed to dry overnight.
  • a 1 mm thick coat of a dispersion of vinyl acetate/dibutyl maleate was applied to a concrete slab (dimensions: 300 X 300 X 20mm). Then strips of a copper cloth having a width of 5 mm (200 meshes) were inserted at a distance of 60 mm from one another, and a 1 mm thick coat of the dispersion was applied thereto.
  • the dispersion contained 8 percent by weight (calculated on the solids content) of carbon black obtained from acetylene.
  • a slab( 300 X 300 mm)of a needle felt carpet was placed onto the wet adhesive. After drying the heating conductor received 200 watt/sq.m. with the use of a voltage of 17 volts.
  • the temperature in the joint was 21 C above room temperature when the concrete slab was placed on a 20 mm thick sheet of polystyrene rigid foam.
  • the temperature in the joint was 35C above room temperature.
  • An electric band heater prepared in the manner described in Example 1 from a dispersion of vinyl acetate/dibutyl maleate containing 8 percent by weight (calculated on the solids content of the dispersion) of carbon black obtained from acetylene and having the dimensions 300 X 6 X 0.2 cm, was installed in a street beneath a 2 cm thick bituminous carpeting. With the use of a voltage of 30 volts, the band heater was supplied with a current of 3.4 arnperes. The following temperatures were measured on a winter-day:
  • band heater 13C At the date when the application was filed, the band heater had lain for a period of about weeks in a much frequented street beneath a factory gate without having sustained damage.
  • the novel flat heating conductors afford a wide range of application. Thy may be used as self-supporting elements for heating streets footpaths, staircases,
  • heating mats according to the process of the present invention, which mats may be employed to protect goods susceptible to freezing in the open air or, for example, as floor heaters in tents, caravans or barracks. 1
  • the process for manufacturing electrical resistance heating elements comprising the steps of preparing a liquid plastic dispersion including vinyl acetate, dibutyl maleate and carbon black, molding said dispersion into a predetermined configuration, embedding at least two metallic conductors in said dispersion in spaced relation to each other and thereafter drying said dispersion.
  • said dispersion preparing step includes the step of mixing said dispersion in a homogeneous mass including parts by weight of a copolymer of said vinyl acetate and dibutyl maleate, having a 50 percent solids content, and 10 parts by weight of said carbon black.
  • said mixing step includes adding 10 parts by weight of fibers to said homogeneous mass, said fibers being selected from the group consisting of polyesters and polyamides.
  • An electrical resistance heating element comprising a sheet of plastic dispersion formed essentially of vinyl acetate and dibutyl maleate filled with carbon black, and at least two metallic conductors embedded in said sheet between opposed surfaces thereof.
  • An electrical resistance heating element as defined in claim 7 including fiber cuttings mixed in said dispersion, said fibers being selected from the group consisting of polyesters and polyamides.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Surface Heating Bodies (AREA)
  • Compositions Of Macromolecular Compounds (AREA)
  • Resistance Heating (AREA)
US116488A 1970-02-20 1971-02-18 Process for the manufacture of flat heating conductors and flat heating conductors obtained by this process Expired - Lifetime US3683361A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19702007866 DE2007866A1 (de) 1970-02-20 1970-02-20 Verfahren zum Herstellen von Flachen heizleitern und nach diesem Verfahren her gestellte Flachenheizleiter

Publications (1)

Publication Number Publication Date
US3683361A true US3683361A (en) 1972-08-08

Family

ID=5762853

Family Applications (1)

Application Number Title Priority Date Filing Date
US116488A Expired - Lifetime US3683361A (en) 1970-02-20 1971-02-18 Process for the manufacture of flat heating conductors and flat heating conductors obtained by this process

Country Status (6)

Country Link
US (1) US3683361A (de)
BE (1) BE763143A (de)
CH (1) CH525594A (de)
DE (1) DE2007866A1 (de)
FR (1) FR2078828A5 (de)
NL (1) NL7101981A (de)

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2923495A1 (de) * 1978-06-15 1980-01-03 Hotfoil Ltd Heizband
US4314231A (en) * 1980-04-21 1982-02-02 Raychem Corporation Conductive polymer electrical devices
US4318220A (en) * 1979-04-19 1982-03-09 Raychem Corporation Process for recovering heat recoverable sheet material
WO1982000935A1 (en) * 1980-08-28 1982-03-18 W Stumphauzer Electric heating device
WO1982001112A1 (en) * 1980-09-18 1982-04-01 Mfg Co Thermon Parallel-type heating cable and method of making same
US4534886A (en) * 1981-01-15 1985-08-13 International Paper Company Non-woven heating element
DE3433669A1 (de) * 1984-02-29 1985-08-29 Buchtal Gmbh, 8472 Schwarzenfeld Flaechiger keramischer formkoerper
US4656339A (en) * 1980-08-28 1987-04-07 Flexwatt Corporation Electrical resistance heater
US4758815A (en) * 1986-07-10 1988-07-19 Tapeswitch Corporation Of America Tap element and methods, for heating, pressure measurement and circuit fabrication
US4823106A (en) * 1986-07-10 1989-04-18 Tapeswitch Corporation Of America Tape element and methods, for heating, pressure measurement and circuit fabrication
US5180900A (en) * 1991-04-15 1993-01-19 Tapeswitch Corporation Of America Electrical resistance element with heat-sensitive disconnect capability
US5586214A (en) * 1994-12-29 1996-12-17 Energy Convertors, Inc. Immersion heating element with electric resistance heating material and polymeric layer disposed thereon
US5835679A (en) * 1994-12-29 1998-11-10 Energy Converters, Inc. Polymeric immersion heating element with skeletal support and optional heat transfer fins
US5930459A (en) * 1994-12-29 1999-07-27 Energy Converters, Inc. Immersion heating element with highly thermally conductive polymeric coating
US6124579A (en) * 1997-10-06 2000-09-26 Watlow Electric Manufacturing Molded polymer composite heater
US6188051B1 (en) 1999-06-01 2001-02-13 Watlow Polymer Technologies Method of manufacturing a sheathed electrical heater assembly
US6233398B1 (en) 1994-12-29 2001-05-15 Watlow Polymer Technologies Heating element suitable for preconditioning print media
US6263158B1 (en) 1999-05-11 2001-07-17 Watlow Polymer Technologies Fibrous supported polymer encapsulated electrical component
US6392206B1 (en) 2000-04-07 2002-05-21 Waltow Polymer Technologies Modular heat exchanger
US6392208B1 (en) 1999-08-06 2002-05-21 Watlow Polymer Technologies Electrofusing of thermoplastic heating elements and elements made thereby
US6433317B1 (en) 2000-04-07 2002-08-13 Watlow Polymer Technologies Molded assembly with heating element captured therein
US6516142B2 (en) 2001-01-08 2003-02-04 Watlow Polymer Technologies Internal heating element for pipes and tubes
US6519835B1 (en) 2000-08-18 2003-02-18 Watlow Polymer Technologies Method of formable thermoplastic laminate heated element assembly
US20040195226A1 (en) * 2001-06-20 2004-10-07 Aldo Stabile Electrothermic membrane with metal core
US20050098684A1 (en) * 2003-03-14 2005-05-12 Watlow Polymer Technologies Polymer-encapsulated heating elements for controlling the temperature of an aircraft compartment
US20060049162A1 (en) * 2004-08-20 2006-03-09 Abbott Richard C Water heater and method of providing the same
US20060210243A1 (en) * 2005-03-17 2006-09-21 Samsung Electronics Co., Ltd. Information recording medium and apparatus for recording information to or reproducing information from the same
US7308193B2 (en) * 2006-02-28 2007-12-11 Richard Halsall Non-metallic heating element for use in a fluid heater
US20120292306A1 (en) * 2011-05-17 2012-11-22 Lai Tso-Liang Floor-Heating Apparatus
US9982900B2 (en) 2014-01-29 2018-05-29 Trane International Inc. Method of attaching electrodes to plated thermoset plastic heated blower housing

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2151626B2 (de) * 1971-10-16 1975-10-23 Reuter Maschinen- Und Werkzeugbau Gmbh, 2844 Lemfoerde Verfahren zur Herstellung eines starren, durch Elektrizität aufheizbaren Flächenheizelementes
FR2526132A1 (fr) * 1982-05-03 1983-11-04 Vasseur Georges Complexe de chauffage mixte, notamment pour installation de chauffage par exemple dans le batiment

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2675420A (en) * 1950-03-28 1954-04-13 Owens Corning Fiberglass Corp Insulated electrical conductor
US3344385A (en) * 1965-01-04 1967-09-26 Dow Corning Flexible resistance element with flexible and stretchable terminal electrodes
US3385959A (en) * 1964-05-29 1968-05-28 Ici Ltd Flexible heating elements
US3417229A (en) * 1965-10-14 1968-12-17 Sanders Associates Inc Electrical resistance heating articles

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2675420A (en) * 1950-03-28 1954-04-13 Owens Corning Fiberglass Corp Insulated electrical conductor
US3385959A (en) * 1964-05-29 1968-05-28 Ici Ltd Flexible heating elements
US3344385A (en) * 1965-01-04 1967-09-26 Dow Corning Flexible resistance element with flexible and stretchable terminal electrodes
US3417229A (en) * 1965-10-14 1968-12-17 Sanders Associates Inc Electrical resistance heating articles

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
The Condensed Chemical Dictionary Reinhold, N.Y. Sixth Edition 1963, p. 12. *

Cited By (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2923495A1 (de) * 1978-06-15 1980-01-03 Hotfoil Ltd Heizband
US4318220A (en) * 1979-04-19 1982-03-09 Raychem Corporation Process for recovering heat recoverable sheet material
US4314231A (en) * 1980-04-21 1982-02-02 Raychem Corporation Conductive polymer electrical devices
GB2138255A (en) * 1980-08-28 1984-10-17 Frederick Gerrard Grise Electric heating device
WO1982000935A1 (en) * 1980-08-28 1982-03-18 W Stumphauzer Electric heating device
US4656339A (en) * 1980-08-28 1987-04-07 Flexwatt Corporation Electrical resistance heater
US4485297A (en) * 1980-08-28 1984-11-27 Flexwatt Corporation Electrical resistance heater
US4392051A (en) * 1980-09-18 1983-07-05 Thermon Manufacturing Company Parallel-type heating cable
WO1982001112A1 (en) * 1980-09-18 1982-04-01 Mfg Co Thermon Parallel-type heating cable and method of making same
US4345368A (en) * 1980-09-18 1982-08-24 Thermon Manufacturing Co. Parallel-type heating cable and method of making same
US4534886A (en) * 1981-01-15 1985-08-13 International Paper Company Non-woven heating element
DE3433669A1 (de) * 1984-02-29 1985-08-29 Buchtal Gmbh, 8472 Schwarzenfeld Flaechiger keramischer formkoerper
DE3433667A1 (de) * 1984-02-29 1985-09-05 Buchtal Gmbh, 8472 Schwarzenfeld Keramischer formkoerper
US4758815A (en) * 1986-07-10 1988-07-19 Tapeswitch Corporation Of America Tap element and methods, for heating, pressure measurement and circuit fabrication
US4823106A (en) * 1986-07-10 1989-04-18 Tapeswitch Corporation Of America Tape element and methods, for heating, pressure measurement and circuit fabrication
US5180900A (en) * 1991-04-15 1993-01-19 Tapeswitch Corporation Of America Electrical resistance element with heat-sensitive disconnect capability
US5586214A (en) * 1994-12-29 1996-12-17 Energy Convertors, Inc. Immersion heating element with electric resistance heating material and polymeric layer disposed thereon
US5835679A (en) * 1994-12-29 1998-11-10 Energy Converters, Inc. Polymeric immersion heating element with skeletal support and optional heat transfer fins
US5930459A (en) * 1994-12-29 1999-07-27 Energy Converters, Inc. Immersion heating element with highly thermally conductive polymeric coating
US6233398B1 (en) 1994-12-29 2001-05-15 Watlow Polymer Technologies Heating element suitable for preconditioning print media
US6432344B1 (en) 1994-12-29 2002-08-13 Watlow Polymer Technology Method of making an improved polymeric immersion heating element with skeletal support and optional heat transfer fins
US6124579A (en) * 1997-10-06 2000-09-26 Watlow Electric Manufacturing Molded polymer composite heater
US6434328B2 (en) 1999-05-11 2002-08-13 Watlow Polymer Technology Fibrous supported polymer encapsulated electrical component
US6263158B1 (en) 1999-05-11 2001-07-17 Watlow Polymer Technologies Fibrous supported polymer encapsulated electrical component
US6188051B1 (en) 1999-06-01 2001-02-13 Watlow Polymer Technologies Method of manufacturing a sheathed electrical heater assembly
US6392208B1 (en) 1999-08-06 2002-05-21 Watlow Polymer Technologies Electrofusing of thermoplastic heating elements and elements made thereby
US6433317B1 (en) 2000-04-07 2002-08-13 Watlow Polymer Technologies Molded assembly with heating element captured therein
US6392206B1 (en) 2000-04-07 2002-05-21 Waltow Polymer Technologies Modular heat exchanger
US6748646B2 (en) 2000-04-07 2004-06-15 Watlow Polymer Technologies Method of manufacturing a molded heating element assembly
US6519835B1 (en) 2000-08-18 2003-02-18 Watlow Polymer Technologies Method of formable thermoplastic laminate heated element assembly
US6541744B2 (en) 2000-08-18 2003-04-01 Watlow Polymer Technologies Packaging having self-contained heater
US6539171B2 (en) 2001-01-08 2003-03-25 Watlow Polymer Technologies Flexible spirally shaped heating element
US6744978B2 (en) 2001-01-08 2004-06-01 Watlow Polymer Technologies Small diameter low watt density immersion heating element
US6516142B2 (en) 2001-01-08 2003-02-04 Watlow Polymer Technologies Internal heating element for pipes and tubes
US20040195226A1 (en) * 2001-06-20 2004-10-07 Aldo Stabile Electrothermic membrane with metal core
US20050098684A1 (en) * 2003-03-14 2005-05-12 Watlow Polymer Technologies Polymer-encapsulated heating elements for controlling the temperature of an aircraft compartment
US20060049162A1 (en) * 2004-08-20 2006-03-09 Abbott Richard C Water heater and method of providing the same
WO2006023979A3 (en) * 2004-08-20 2006-09-28 Thermoceramix Inc Water heater and method of providing the same
US7123825B2 (en) * 2004-08-20 2006-10-17 Thermoceramix, Inc. Water heater and method of providing the same
US20060210243A1 (en) * 2005-03-17 2006-09-21 Samsung Electronics Co., Ltd. Information recording medium and apparatus for recording information to or reproducing information from the same
US7308193B2 (en) * 2006-02-28 2007-12-11 Richard Halsall Non-metallic heating element for use in a fluid heater
US20120292306A1 (en) * 2011-05-17 2012-11-22 Lai Tso-Liang Floor-Heating Apparatus
US9982900B2 (en) 2014-01-29 2018-05-29 Trane International Inc. Method of attaching electrodes to plated thermoset plastic heated blower housing

Also Published As

Publication number Publication date
CH525594A (de) 1972-07-15
DE2007866A1 (de) 1971-09-09
BE763143A (fr) 1971-08-18
NL7101981A (de) 1971-08-24
FR2078828A5 (de) 1971-11-05

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