US2836518A - Modified polyvinyl acetal insulated conductors - Google Patents

Modified polyvinyl acetal insulated conductors Download PDF

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Publication number
US2836518A
US2836518A US396582A US39658253A US2836518A US 2836518 A US2836518 A US 2836518A US 396582 A US396582 A US 396582A US 39658253 A US39658253 A US 39658253A US 2836518 A US2836518 A US 2836518A
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United States
Prior art keywords
aldehyde
weight
resin
formaldehyde
phenol
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
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US396582A
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English (en)
Inventor
John A Loritsch
Edward W Daszewski
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General Electric Co
Original Assignee
General Electric Co
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Filing date
Publication date
Priority to CA564569A priority Critical patent/CA564569A/en
Application filed by General Electric Co filed Critical General Electric Co
Priority to US396582A priority patent/US2836518A/en
Priority to DEG15165A priority patent/DE1026387B/de
Priority to JP1799754A priority patent/JPS3515243B1/ja
Application granted granted Critical
Publication of US2836518A publication Critical patent/US2836518A/en
Anticipated expiration legal-status Critical
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H01B3/44—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes vinyl resins; acrylic resins
    • H01B3/448—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes vinyl resins; acrylic resins from other vinyl compounds
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H01B3/44—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes vinyl resins; acrylic resins
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B7/00—Insulated conductors or cables characterised by their form
    • H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
    • H01B7/28—Protection against damage caused by moisture, corrosion, chemical attack or weather
    • H01B7/2806—Protection against damage caused by corrosion
    • 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
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
    • Y10T428/2913—Rod, strand, filament or fiber
    • Y10T428/2933—Coated or with bond, impregnation or core
    • Y10T428/294—Coated or with bond, impregnation or core including metal or compound thereof [excluding glass, ceramic and asbestos]
    • 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
    • Y10T428/00—Stock material or miscellaneous articles
    • Y10T428/31504—Composite [nonstructural laminate]
    • Y10T428/31678—Of metal
    • Y10T428/31688—Next to aldehyde or ketone condensation product

Definitions

  • This invention relates to resinous compositions and conductors insulated therewith. More particularly, the invention is concerned with improved enamels comprising polyvinyl acetals and to electrical conductors provided with such enamels.
  • Patnode and Flynn l atent 2,085,995 assigned to the assignee of the present invention, discloses insulated conductors provided with coating compositions comprising polyvinyl acetal resins. Although such insulated conductors have distinct advantages over conductors insulated with conventional oil-type enamels, the resinous compositions utilized therein are costly, and comparatively high priced solvents are required for the production of suitable Wire enamels therefrom.
  • Jackson and Hall Patent 2,307,- 588 also assigned to the assignee of the present invention, discloses insulated conductors provided with an improved and less expensive resinous composition which additionally is soluble in relatively inexpensive solvents.
  • insulated conductors having properties practically the same, and in certain respects even better than those described in the above Patnode et al. patent, can be made and at a substantially lower cost by combining suitable phenol-aldehyde resins with the polyvinyl acetal resin.
  • conductors insulated with the Jackson and Hall compositions are eminently satisfactory for most applications, they do not possess the required solvent resistance necessary in certain instances, for example, when used in hermetically sealed motors of refrigerators.
  • the attainment of adequate solvent resistance in addition to abrasion and heat resistance, as well as dielectric strength and other qualities possessed by the aforementioned Patnode and Flynn, and Jackson and Hall compositions has presented a problem, particularly to the magnet wire industry.
  • aldehyde-ammonia derivative condensates which are useful as additives herein are condensates formed by the known reaction of aldehydes, and particularly formaldehyde, with ammonia derivatives including amines and amides and, more particularly, with ureas and thioureas, etc., to form, e. g., urea-aldehyde condensates in the usual manner.
  • aldehyde-amine and aldehyde-amide condensates are produced by the reaction of urea, thiourea and various substituted ureas and urea derivatives with aldehydes such as formaldehydes to form condensates, e.
  • aldehyde-ammonia derivative condensates found eminently suitable for improving the solvent resistance of phenolic modified polyvinyl acetal compositions are the soluble condensates, i. e., the condensates which are soluble with and compatible with the resin composition. condensates having these properties and coming within the scope of the present invention are believed to have the grouping i ll.
  • R is a radical of the class consisting of hydrogen, alkyl, aryl, alkaryl, aralkyl, a hetero oxygen-containing radical, forexample, furyl and R is a radical of the class consisting of hydrogen,
  • alkyl aryl, alkaryl, aralkyl, a pyrrole residue, for example,
  • H o HC 0 l r (JJNH- and R in the second group having the same scope as in the first group, and n is an integer equal to or greater than one.
  • condensates of aldehydes and ammonia derivatives particularly urea-aldehyde condensates, prepared in the presence of alcoholic or other solvents which take part in the reaction and thus 'become an integral part of the resulting resin composition, as Where butyl alcohol is present in the production of urea formaldehyde condensates to give butylated products.
  • polyvinyl acetal resins employed in the process of this invention are hydrolyzed, polymerized vinyl ester aldehyde condensation products which may be produced from various aldehydes and various polyvinyl esters as more fully set forth in said Patnode et ,al. patent, and more fully described in Reissue Patent 20,430 to Morrison et al.
  • Aldehydes other than formaldehyde may be used in making polyvinyl acetal resins, for example, acetaldehyde, propionic aldehyde, butyric aldehyde, benzaldehyde and the like.
  • polyvinyl esters other than polyvinyl acetate may *be employed, for instance, polyvinyl propionate, polyvinyl butyrate and the like.
  • the properties of polyvinyl acetal resins may 'be varied through a wide range by varying the viscosity and the extent of the hydrolysis of the polyvinyl ester, the amount and the character of the aldehyde reacted with the hydrolyzed poly- Patented May 27,1958
  • test involved immersingthelengths of wires in a boiling mixture of 50 parts of alcohol,iforiexample,
  • This enamel was usedfto coat.0508" wire at various speeds ranging from; 14 feet per minute to 21 feetper after which time the wires were inspected for signs of of visible attack.
  • Example 10 A resin having a solids content of 16% composed of 5 i e 7' K 7 5 Percent by weight Cresol-formaldehyde resin 5.33 Polyvinyl formal resin l. 10.67
  • the butylated urea-formaldehyde condensate wasan 3 alcoholic -type"of ureaformaldehyde resinr'esulting from the reaction of the resin with an alcohol. (trade name Ufor'mite 240-N);
  • the resulting composition was agitated with a stirrer for approximately ene hour to insure good blending. It may be dyed, 1f des1red,.b'y adding a small amount of a suitabledye during the'stirring.
  • theenamel is filtered through ,a
  • Example 2 To the enamel of Example 1, 12%, by weight, based on the weight of resin solids represented by the poly-' vinyl formal resin, of trimethylol urea 'having the' formula was added in place of the butylated urea-formaldehyde condensate and the composition processed and tested for solvent resistance as in Example 1. Again in each case, the solvent resistance wasexcellent. e
  • Example 1 To the enamel of Example 1 were addedin lieu of the butylated urea-formaldehyde condensate," various amounts of a pyrrole-formaldehyde condensate prepared by reacting formaldehyde with pyrrole in approximately equirnolecular proportion having the formula wherein n is greater than one, specifically from 0.3 to 12%, by weight, based on the weight of resin solids represented by the polyvinyl formal resin, and each composition processed and solvent tested as in Example 1.
  • Example 1 To the enamel of Example 1 was addedin placelof the butylated urea-formaldehyde condensate 0.3%, by weight, based on the weight of resin solids represented by the polyvinyl formal, of an aniline-formaldehyde con- 1 densate prepared by dissolving 100 parts of aniline in'SOO parts of 95% alcohol and refluxing with parts of 37% formaldehyde. 7 1
  • Additional examples include the petrol-alkyl type phenols, which petroalkyl phenols may be used as the sole phenolic body or in combination with coal-tar phenol, cresols and other phenolic substances.
  • active methylene-containing bodies other than formaldehyde may be used, either in solid or solution state.
  • the properties of the phenol-aldehyde resin and accordingly the properties of the additive modified phenolaldehyde-polyvinyl acetal resinous compositions may be varied by varying the ratios of the phenolic body and the aldehyde. For example, resins containing 0.7 or more mols formaldehyde will convert to a substantially infusible insoluble state when heated at elevated temperatures whereas those containing 0.5 or 0.6 mol formaldehyde are thermoplastic.
  • thermoplastic resins may be used as modifying agents of the polyvinyl acetal resin in general, it is preferred to use in the preparation of wire enamels those phenolic resins which are produced by reacting 1 mol phenolic body with from 0.7 to 2.0 mols of an active methylene-containing body such as formaldehyde or other suitable aldehyde. No particular advantage is gained by using more than 2 mols formaldehyde to 1 mol of the phenolic body since the excess formaldehyde is volatilized during the cooking of the resin.
  • Enameled wires are produced by drawing the clean wire, for example, clean copper wire through a body of wire enamel made by incorporating the modifying phenolaldehyde resin, polyvinyl acetal resin, solvent and ammonia derivative-aldehyde condensate.
  • the proportions of phenolic and polyvinyl acetal resins may be varied, for example, from, by weight, about 5 to 50 parts phenolic resins to form about 95 to 50 parts polyvinyl acetal resin.
  • the total resin to solvent proportions also may be varied, for instance, from about 5 to 25 parts resin to about 95 to 75 parts solvent.
  • concentrations of aldehyde-ammonia derivative condensate additive to phenolic resin modified polyvinyl acetal enamels found suitable to improve solvent resistance in accordance with the present invention is wide. Excellent results have been obtained by employing 0.1% to 5%, by weight, based on the weight of resin solids represented by the polyvinyl acetal resin. A preferred range is from 0.3 to 1.2%, by weight, based on the weight of resin solids represented by the polyvinyl acetal resin employed.
  • ammonia derivative-aldehyde condensates coming within the scope of the present invention are those which are substantially completely soluble in the enamel and compatible therewith. Condensates which are not soluble or only slightly soluble or which are incompatible with the enamel are ineffective for the present purposes.
  • aldehydes condensible with an gmmonia derivative to give the present condensates include, in addition to the formaldehyde and acetaldehyde of the examples, for instance, propionaldehyde, n-butyraldehyde, isobutyraldehyde, nvaleraldehyde, isovaleraldehyde, n-caproaldehyde, etc., benzaldehyde and the like.
  • the method of coating the aforedescribed wires was in accordance with the procedure disclosed in the Jackson et al. patent. For example, after the wire had been passed through a bath containing the particular wire enamel, the coated wire was subjected to heat by introducing it into a suitable oven wherein the enamel was baked at a suitable temperature, for example, at an oven temperature of about 250 to 500 C. The coating was baked simultaneously with the annealing of the copper. As previously mentioned, the wire was drawn through the bath at various speeds ranging from 14 feet per minute to 21 feet per minute. Usually, it was necessary to run the wire successively through the enamel bath and baking oven several times at a constant speed in order to provide adequate insulation thereon.
  • the phenolic resin modified polyvinyl acetal resin having incorporated therein an ammonia derivativealdehyde condensate is particularly applicable to the manufacture of wire enamels and insulated conductors, it will be appreciated that its field of utility is not limited thereto. For'example, it may be used to improve the solvent resistance of phenolic resin-modified polyvinyl acetal resin heretofore used as an adhesive for cementing together such materials as mica flakes to form bonded mica sheet insulation, as a cementing agent to bond together fibrous materials in sheet, tape, felted, or other form and as a coil impregnating varnish.
  • the additive containing phenolic resin modified polyvinyl acetal resins may be made in the form of solvent resistant thin sheets or tapes and used alone or adhesively bonded to, or otherwise in combination with, other materials such as paper, cellulose, esters, cellulose ethers, etc., as coil layer insulation.
  • Such sheets or tapes having improved solvent resistance also may be applied to a conductor, according to well-knownstrip covering meth-r od s, as insulationtherefon ⁇ They may be heat-treated to improve their properties either before, during application.
  • An insulated copper conductor in which the outer insulation therefor comprises essentially a hard, flexible, tough, abrasion-resistant and Freon-resistant coating, said coating being the' heat-treated product of a mixture of ingredients consisting essentially, by weight, of (1) from 95 to 50 percent of a polyvinyl formal resin obtained 7 by condensing formaldehyde with a product of hydrolysis of polyvinyl acetate, (2) from to 50 percentrof a heat -hardenable resin obtained by condensing a phenol selected from the class consisting of phenol, cresol,
  • a condensation product selected fromtthe group consisting of urea-aldehyde, alkylated urea aldehyde, pyrrolealdehyde, aromatic amine aldehyde, and thiourea-aldehyde condensates
  • condensation product contained in the insulation comprises a butylated urea-formaldehydecondensate,v 3.' T he insulated electrical conductor of claim 1 in;
  • condensation product contained 7 in t i ular tion comprises trimethylol, ureali 4.
  • the insulated electrical conductor of claim whichthe condensation product in the insulation comprises a pyrrole-formaldehyde condensate.

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  • Physics & Mathematics (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Organic Insulating Materials (AREA)
  • Paints Or Removers (AREA)
US396582A 1953-08-26 1953-12-07 Modified polyvinyl acetal insulated conductors Expired - Lifetime US2836518A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CA564569A CA564569A (en) 1953-08-26 Polyvinyl acetal insulated conductors
US396582A US2836518A (en) 1953-08-26 1953-12-07 Modified polyvinyl acetal insulated conductors
DEG15165A DE1026387B (de) 1953-08-26 1954-08-21 Isolierter elektrischer Leiter, dessen aeussere Isolierung aus einem waermebehandelten Kunstharz besteht
JP1799754A JPS3515243B1 (US07122603-20061017-C00187.png) 1953-08-26 1954-08-24

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CA564569T
US1026387XA 1953-08-26 1953-08-26
JP131757 1953-08-26
US396582A US2836518A (en) 1953-08-26 1953-12-07 Modified polyvinyl acetal insulated conductors

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US2836518A true US2836518A (en) 1958-05-27

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US (1) US2836518A (US07122603-20061017-C00187.png)
JP (1) JPS3515243B1 (US07122603-20061017-C00187.png)
CA (1) CA564569A (US07122603-20061017-C00187.png)
DE (1) DE1026387B (US07122603-20061017-C00187.png)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2917416A (en) * 1955-10-25 1959-12-15 Shawinigan Resins Corp Polyvinyl acetal-phenol aldehyde resin wire enamel and method of using same
US3069379A (en) * 1959-04-13 1962-12-18 Shawinigan Resins Corp Composition comprising a polyvinyl acetal, a phenol-aldehyde resin and a polyisocyanate, process for preparing same, and electrical conductor coated therewith

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1419988A1 (de) * 1960-06-09 1969-03-20 Bayer Ag Einbrennbare UEberzugsmittel

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2239441A (en) * 1940-06-20 1941-04-22 Gen Electric Aldehyde reaction products with nitrogen-containing methylene compounds
US2290675A (en) * 1939-08-10 1942-07-21 Gen Electric Condensation product of an aliphatic aldehyde and an unsaturated amide
US2292334A (en) * 1941-10-29 1942-08-04 Gen Electric Aldehyde-acetoacetanilide condensation product
US2292333A (en) * 1941-10-30 1942-08-04 Gen Electric Reaction product of an aldehyde and di-(acetoacetyl) ethylene diamine
US2307588A (en) * 1938-07-08 1943-01-05 Gen Electric Insulated electrical conductor
US2466399A (en) * 1943-10-15 1949-04-05 Monsanto Chemicals Thermosetting polyvinyl acetal composition
US2687385A (en) * 1951-12-29 1954-08-24 Anaconda Wire & Cable Co Wire coating composition
US2730466A (en) * 1954-08-30 1956-01-10 Gen Electric Insulated electrical conductor

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB669127A (en) * 1949-08-12 1952-03-26 Basil Jacob Improvements in or relating to insulated electrical conductors

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2307588A (en) * 1938-07-08 1943-01-05 Gen Electric Insulated electrical conductor
US2290675A (en) * 1939-08-10 1942-07-21 Gen Electric Condensation product of an aliphatic aldehyde and an unsaturated amide
US2239441A (en) * 1940-06-20 1941-04-22 Gen Electric Aldehyde reaction products with nitrogen-containing methylene compounds
US2292334A (en) * 1941-10-29 1942-08-04 Gen Electric Aldehyde-acetoacetanilide condensation product
US2292333A (en) * 1941-10-30 1942-08-04 Gen Electric Reaction product of an aldehyde and di-(acetoacetyl) ethylene diamine
US2466399A (en) * 1943-10-15 1949-04-05 Monsanto Chemicals Thermosetting polyvinyl acetal composition
US2687385A (en) * 1951-12-29 1954-08-24 Anaconda Wire & Cable Co Wire coating composition
US2730466A (en) * 1954-08-30 1956-01-10 Gen Electric Insulated electrical conductor

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2917416A (en) * 1955-10-25 1959-12-15 Shawinigan Resins Corp Polyvinyl acetal-phenol aldehyde resin wire enamel and method of using same
US3069379A (en) * 1959-04-13 1962-12-18 Shawinigan Resins Corp Composition comprising a polyvinyl acetal, a phenol-aldehyde resin and a polyisocyanate, process for preparing same, and electrical conductor coated therewith

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Publication number Publication date
CA564569A (en) 1958-10-14
JPS3515243B1 (US07122603-20061017-C00187.png) 1960-10-13
DE1026387B (de) 1958-03-20

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